<RECORD 1>
Accession number:20151000594718
Title:Longitudinal stability control of orchard cable-driven hanging transport system
Authors:Yang, Zhou (1); Li, Wei (1); Li, Jun (1); Li, Xueping (1); Xue, Kunpeng (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou, China
Corresponding author:Li, Jun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:64-70
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A cable-driven hanging transport system has the characteristics of labor saving, economic efficiency and good revenue, along with good prospect for increasing orchard utilization. Compared with the wheeled carrier and crawler, it can meet the demand of the complex mountainous topography. Both during and after transfer, the load motion of the hanging system can cause load swings, which is undesirable especially in the variations of acceleration. The longitudinal oscillations may lead to the instability of system and damage of agricultural goods. The aim of this paper is to develop an effective control method for the load motion that produces short travel time with suppressed load swing and satisfies operational constraints. Due to the nonlinearities of spatial three-dimensional motion of transferred load, the dynamics of the cable-driven hanging transport system showed complexity with coupled motion of load. In fact, the lateral movement had little effect on the longitudinal stability due to the low transport speed of cable and lager curvature radius of rails, which could be ignored in the development of plant equations. In order to effectively suppress the longitudinal load swings, the Lagrange equations were utilized and a mathematical model of the transport system was proposed. The transport system with multiple load masses in series can be considered as similar to the hoist system with a single concentrated load. The reason is that the distances between each hook point and mass center of load are at roughly the same value. As a result, the dynamic model of the transport system can be simplified to a linearized model by ignoring the effect of lateral movement and assuming the multiple load masses in series to be a single load mass. The state-space form of longitudinal equations of load motion was developed and its controllability and observability was analyzed. The system transfer function was obtained. From the performance specifications, a compensated controller with root locus correction was proposed by reshaping the root locus in order that the dominant closed-loop poles can be at desired locations in the complex plane. The damping ratio and natural frequency were specified. The designed procedure of root locus correction was achieved by adjusting the compensator pole and zeros with the addition of two zeros, which make the pole on the positive real axis move into the left half complex plane by eliminating the remaining zero at the origin plane. Because all the roots have negative real parts after reshaping the root locus, the closed-loop transport system was stable. The simulation and experimental results confirmed that the designed system was acceptable. The damping time was considerably reduced as compared with the original system without root locus correction. The stability of the transport system was guaranteed by the proposed controller with root locus correction for all values of gain, which can suppress the longitudinal swing angle within ±1.5° and reduce the maximum magnitude of in-plane swing angular velocity to 10% of that of the original system. In terms of the transporting time and process stability, the proposed control method can offer significant improvement in the actual operations of a hanging transport system. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Control system stability
Controlled terms:Agricultural machinery - Agriculture - Cables - Control nonlinearities - Controllers - Damping - Equations of motion - Farms - Longitudinal control - Models - Motion control - Orchards - Poles - Root loci - Stability - State space methods - System stability - Transportation - Travel time
Uncontrolled terms:Controllability and observabilities - Longitudinal oscillations - Operational constraints - Performance specifications - Stability control - System transfer function - Three-dimensional motion - Transport systems
Classification code:408.2 Structural Members and Shapes - 431 Air Transportation - 432 Highway Transportation - 433 Railroad Transportation - 434 Waterway Transportation - 535 Rolling, Forging and Forming - 731 Automatic Control Principles and Applications - 732.1 Control Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.010
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 2>
Accession number:20151000594741
Title:Risk assessment of non-point source pollution export in Lasahe basin
Authors:Fang, Guangling (1); Xiang, Bao (1); Du, Jiaqiang (1); Wang, Baoliang (1); Zhang, Likun (1); Hu, Yu (3); Xu, Jie (1)
Author affiliation:(1) Chinese Research Academy of Environmental Sciences, Beijing, China; (2) State Environment Protection Key Laboratory of Regional Ecological Processes and Functions Assessment, Beijing, China; (3) College of Water Sciences, Beijing Normal University, Beijing, China
Corresponding author:Xiang, Bao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:247-254
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Identification of the high risk area of non-point source pollution has important practical significance to control non-point source pollution and improve the water environment quality. Lasahe River basin located in the Tibet Autonomous Region of China is important drinking-water source for Lhasa City, Linzhou County and Dangxiong County. Because the underdevelopment of industry and the less discharge of industrial pollutants in this area, non-point source pollution is the most important contributing factor for water pollution. Lhasa River basin is the region of agricultural production base with the densest population in the Tibet Autonomous Region. This study built the output risk model that includes rainfall, topography, and fertilization influence factor, identification the output risk region unit from basin non-point source pollution at all levels object. The risk probability of non-point source pollution was classed into five levels: lowest, lower, moderate, higher and highest. Data used in this study were mainly from remote sensing image, statistical yearbook, and the parameters in output risk model were collected from the literatures. The results showed that risk probability of non-point source pollution output in 1996 and 2010 was 50% and 46.3% respectively. 17.5% in 1996 and 12.6% in 2010 of the study area showed that risk probability of non-point source pollution was more than 70%. The risk probability of non-point source pollution was spatially heterogeneous, corresponding with the attributes of land use types. The areas with highest risk of non-point source pollution were concentrated in farmland, where agricultural activities strengthened, and concentrated in unused land with great ecological vulnerability and sensitivity to external interference. Areas with lowest and lower risk of non-point source pollution mainly distributed in grassland, which has relative stability and robustness. Our study also found that risk probability of non-point source pollution was closely related with slope, the risk enhanced as the slope increased, and moderate risk, higher risk and highest risk mainly distributed in the area with slope greater than 15 degree. Compared with 1996, the area that non-point source pollution degree of risk transformation from lowest and lower level to higher and highest level in 2010 was about 6674.3 km<sup>2</sup>. Lasahe basin non-point source pollution risk probability was medium risk level, and degree of risk decreased in the local scope. And the area of highest risk reduced, and the area of low risk increased, but the area of medium and higher risk had a tendency to increase. Land use change, agricultural production and water-soil erosion are the material cause of the basin non-point source pollution. Areas characterized by conversion from grassland to farmland and from grassland to unused land showed markedly changes in risk probability of non-point source pollution. These results would offer useful information for limiting non-point pollution and helping promote better water quality in the Lhasa River basin. The risk assessment of non-point source pollution provide an easy, verifiable, viable way to identify areas prone to non-point source pollution, supporting to design and apply adaptive management strategies. Therefore, it needs to strengthen the ecological environment comprehensive treatment results, tackle non-point source pollution in advance, formulate plans for the development of ecological agriculture, and build controlling non-point source pollution migration vegetation buffer. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:River pollution
Controlled terms:Agriculture - Ecology - Farms - Identification (control systems) - Image reconstruction - Land use - Models - Pollution - Pollution control - Potable water - Probability - Quality control - Remote sensing - Risk analysis - Risk assessment - Risks - Rivers - Water - Water pollution - Water pollution control - Water quality - Water resources - Watersheds
Uncontrolled terms:Agricultural activities - Agricultural productions - Ecological agricultures - Ecological vulnerability - Non-point source pollution - Risk model - The Lasahe basin - Tibet autonomous region
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 444.1 Surface Water - 453 Water Pollution - 453.2 Water Pollution Control - 454.2 Environmental Impact and Protection - 454.3 Ecology and Ecosystems - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 911 Cost and Value Engineering; Industrial Economics - 912 Industrial Engineering and Management - 913.3 Quality Assurance and Control - 914 Safety Engineering - 922 Statistical Methods - 922.1 Probability Theory
DOI:10.3969/j.issn.1002-6819.2015.01.033
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 3>
Accession number:20151000594751
Title:Effect of high-pressure thermal sterilization on quality of compound fermented wheat flour paste
Authors:Chen, Jing (1); Ren, Xin (1); Lou, Ge (1); Shen, Qun (1)
Author affiliation:(1) College of Food Science and Nutritional Engineering, China Agricultural University, Beijing, China; (2) National Engineering Research Center for Fruits and Vegetables Processing, Beijing, China
Corresponding author:Shen, Qun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:326-332
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Compound fermented wheat flour paste is favored by Chinese consumers as a traditional condiment, which is made of fermented wheat flour by Aspergillus oryzae. During the fermentation process, sterilization plays a key role, because the compound fermented wheat flour paste is prone to getting polluted. Heat sterilization is a conventional and simple method to kill the microorganisms in the products. However, the method has undesirable influences on the qualities of the product such as texture and flavor due to uneven heating. Besides, the microorganisms cannot be killed thoroughly. The high-pressure thermal sterilization (HPTS) is a new type of sterilization technology which combines the methods of pressure and temperature. And this approach can extend the shelf life and maintain the safety of the products. The properties such as rheological characteristics, color, specific aroma compositions and fatty acid compositions in the compound fermented wheat flour paste before and after processed by the HPTS were analyzed, in order to study on the quality of the compound fermented wheat flour paste. Samples were subjected to different pressure treatments (300, 400 and 500 MPa) for 10 min at 45, and then the properties of rheological characteristics, color, specific aroma compositions of all the samples were analyzed by rheometer, automatic chromatic meter, and GC-MS, respectively. The results showed that under HPTS treatment the viscosity of the compound fermented wheat flour paste reduced, and with the increasing of the pressure, the viscosity decreased. However, the compound fermented wheat flour paste was still pseudoplastic fluid, and the type of the fluid was not changed after the processing. Besides, after dealed with the HPTS processing, the chromatic aberration of these samples reduced significantly, and the brown index (BI) declined. But there was no significant change in the level of the parameter of the properties of color (L* and a*), which present the brightness and the degree of the red and green, respectively. In addition, the volatile flavor substances in the compound fermented wheat flour paste mainly contained aldehydes and esters. 5-Methyl-2-phenyl-2-hexenal, Furfural and ethyl oleate were the main aroma components. After treated, various aldehydes content decreased significantly. In particular ethyl oleate cannot be detected in the processed samples. However, the contents of phenylacetaldehyde and limonene increased. Moreover, there were new compositions such as benzaldehyde and phenethyl alcohol found in the processed samples. Finally, the fatty acids contents of the samples were analyzed and the fatty acids composition didn't change significantly after the HPTS treatment at 400 MPa, 45, 10min, except the content of the oleic acid. To sum up, there was no significant change in the properties of color (L* and a*), specific aroma compositions and fatty acids compositions of the compound fermented wheat flour paste; the viscosity of the samples treated at 400 MPa was similar with the unprocessed samples than the samples treated at 500 MPa HPTS. Therefore, the treatment of HPTS at 400 MPa, 45, 10min could maintain the quality of the compound fermented wheat flour paste such as texture, color, specific aroma compositions and fatty acids compositions. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Fatty acids
Controlled terms:Aberrations - Aldehydes - Aspergillus - Color - Fermentation - Flavor compounds - Flavors - High pressure effects - Microbiology - Microorganisms - Odors - Sterilization (cleaning) - Textures - Viscosity
Uncontrolled terms:Color changes - Effect of high pressure - Fatty acid composition - High pressure thermal sterilizations - Pressure and temperature - Rheological characteristics - Sterilization technology - Wheat flours
Classification code:451.1 Air Pollution Sources - 461 Bioengineering and Biology - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 804.1 Organic Compounds - 822.2 Food Processing Operations - 822.3 Food Products - 931.2 Physical Properties of Gases, Liquids and Solids - 933 Solid State Physics
DOI:10.3969/j.issn.1002-6819.2015.01.043
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 4>
Accession number:20151000594715
Title:Design and experiment on transplanter pot seedling disk conveying and positioning control system
Authors:Wu, Jianmin (1); Zhang, Xiaochao (1); Jin, Xin (2); Liu, Zhongjun (1); Zhu, Licheng (1); Sun, Xin (1); Zou, Zhuoran (1); Liu, Bangsi (1)
Author affiliation:(1) Chinese Academy of Agricultural Mechanization Sciences, Beijing, China; (2) College of Agricultural Engineering, Henan University of Science and Technology, Luoyang, China
Corresponding author:Jin, Xin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:47-52
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to solve the problem of seedlings leakage planting caused by the lack of plug seedlings in trays during with the all automatic transplanter working, an automatic recognition and control device for vegetable plug seedling transplanter was designed. In contrast to the home and abroad information, the design considered the domestic user price affordability and practicality. In this device, a stepping motor was used for driving the seedling disc horizontal motion and another was used for driving the seedling disc vertical motion. Four photo-electric sensors as the seedling recognition device were fitted on both sides of the seedling gripper and seedling disc, which can detect of seedling shortage from four directions. A programmable logic controller (PLC) was used to control clamping seedling gripper motion and the seedling disc transport along horizontal and vertical direction. A touch screen as man-machine interface can set the parameter to fit different size seedling disc, which can also choose manually or automatic control method. In this paper, a comparative experiment f was carried out at different transplanting velocity under the condition of automatic recognition system or one month old pepper seedling. The results showed that it could work effectively. The movement of the seedling trigger photoelectric sensor produced a signal, so that the seedlings were stopped and clamped away when moving to the position of the seedling gripper. On the contrary, the lack of seedling lattice cannot trigger photoelectric sensor, on arrival will not stop the seedling fetching device position, but quickly through, directly send the next seedling to stop on position of the seedling gripper, waiting for the clamping seedling gripper. This improves the seedling grab efficiency, reducing the leakage rate of transplanting machine plant. Automatic recognition and control device had low misjudge rate when transplanting speed was form 60 to 120 seedling per minutes. When transplanting speed was from 60 to 90 seedling per minute, the transplanter had well leakage plantings rate and throwing seedlings rate that can effectively work at transplanting seedling. The response speed of automatic recognition and control device can work at high speed transplanter. The leakage transplanting rate with automatically seedlings picking recognition control system was 12% lower than without the automatically seedlings picking control system. The device achieved the objective of reducing leakage rate purpose. Relative to not used for automatic identification of transplanting seedling mode, it is reduced about 12% that the leakage rate of the whole system of plant in 60-90 seedling /min transplanting speed. Leakage rate of transplanting machine plant is close to the practical level of planting. It achieved the purpose of reducing the leakage rate of planting. Through observation and analysis during experiments, if the conveying of seedling disk was changed to horizontal, it can maximize the seedling erect and reducing sensor misjudgment caused by seedling roll or tilt, the identification rate was improved. The system was only carried out in the laboratory test, but field test has not yet performed. In field operation, some factor may affect the automatic recognition and seedling fetching device reliability and stability, such as vibration of machines, interference of the sensor by sunshine outdoor. These need further test and examination. More field experiment needs to be tested for the influences of machine vibration and sunlight to the photoelectric sensor. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Identification (control systems)
Controlled terms:Agricultural machinery - Automation - Control systems - Grippers - Photoelectricity - Seed - Sensors - Speed - Stepping motors - Touch screens - Transplants
Uncontrolled terms:Automatic identification - Automatic recognition system - Comparative experiments - Man machine interface - Photoelectric sensors - Positioning control system - Programmable logic controllers (PLC) - Transplanting machine
Classification code:462.4 Prosthetics - 705.3 Electric Motors - 722.2 Computer Peripheral Equipment - 731 Automatic Control Principles and Applications - 732 Control Devices - 741.1 Light/Optics - 801 Chemistry - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.007
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 5>
Accession number:20151000594750
Title:Effect of cooking final temperature and cutting method on eating quality of pan-fried steak
Authors:Lang, Yumiao (1); Xie, Peng (1); Li, Jing (1); Li, Haipeng (1); Sun, Baozhong (1)
Author affiliation:(1) Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China
Corresponding author:Sun, Baozhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:317-325
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the improvement of economy and people's living standard, ready-to-eat food gets the welcome of food industry and consumers. Pan-fried beef steak became more and more popular in China due to its high nutrition, good quality and convenient to cook. Beef steak in Chinese market had poor quality consistency, different sizes and shapes, and these were the reasons that beef steak cannot meet consumers' demand for high and consistent quality of beef steak products. Cooking final temperature, slice thickness and fiber direction are important factors to affect eating quality of beef steak. The aim of this paper is to study how cooking final temperature (45, 60, 72, 80, 90 and 100), slice thickness (2, 5, 10, 12.7 and 25.4 mm) and fiber direction (parallel and perpendicular) affect eating quality of pan-fried steak. Twelve Chinese Simmental bulls, of the same rearing condition, were selected from the same pasture. M. longissimus were excised from the left carcasses and used to study the effect of cooking final temperature, slice thickness and fiber direction on WBSF (Warner-Bratzler Shear Force), texture profile analysis (TPA) and sensory quality evaluation of steak. The results showed that cooking final temperature, slice thickness and fiber direction had significant effect on WBSF, cooking yield, TPA and sensory quality evaluation to some extent. As increasing cooking final temperature, WBSF, cooking loss, hardness and chewiness increased (P<0.05), but cooking loss value decreased (P<0.05). Initial tenderness, overall tenderness and juiciness were significantly decreased with cooking final temperature increased (P<0.05). Beef flavor and overall acceptability of cooking final temperature from 72 to 100 were significant higher than cooking final temperature from 45 to 60 (P<0.05). Slice thickness had significant effect on eating quality of pan-fried beef steak. The WBSF value increased with the increase of slice thickness (P<0.05). However, WBSF of per thickness (mm) decreased (P<0.05). Hardness and chewiness of 5 mm, 10 mm and 12.7 mm had no significant difference (P>0.05), but significant higher than that of 25.4 mm (P<0.05). Slice thickness had significant effect on overall tenderness (P<0.05), but had no effect on initial tenderness, juiciness, flavor and overall acceptability (P>0.05). Overall tenderness decreased with slice thickness increased. WBSF, WBSF of per thickness (mm), cooking loss, hardness and chewiness of parallel to fiber direction were significant lower than that of perpendicular to fiber direction (P<0.05). Fiber direction had significant effect on initial tenderness (P<0.05) and initial tenderness score of perpendicular to fiber direction was significant higher than that of parallel to fiber direction. However, slice thickness had no significant effect on juiciness, flavor and overall acceptability (P>0.05). Slice thickness and fiber direction had no significance effect on cooking loss and cooking yield (P>0.05). In conclusion, cooking final temperature, slice thickness and fiber direction had significant effect on eating quality of pan-fried steak. In order to satisfy the needs of consumers, beef industry and consumers should pay attention to cooking final temperature, slice thickness and fiber direction and the suggested technical parameters are 80 (cooking final temperature), 10 mm thickness (slice thickness) and perpendicular to fiber direction (fiber direction). ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Cooking
Controlled terms:Beef - Fibers - Food products - Hardness - Meats - Quality control - Sensory analysis - Shear flow - Temperature - Textures
Uncontrolled terms:Fiber direction - Final temperatures - Overall acceptability - Quality consistency - Ready-to-eat foods - Shear force - Slice thickness - Texture profile analysis
Classification code:421 Strength of Building Materials; Mechanical Properties - 641.1 Thermodynamics - 812 Ceramics, Refractories and Glass - 817 Plastics and Other Polymers: Products and Applications - 822.2 Food Processing Operations - 822.3 Food Products - 913.3 Quality Assurance and Control - 933 Solid State Physics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.042
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 6>
Accession number:20151000594724
Title:Effects of rotational tillage systems on soil production performance in wheat-maize rotation field in Loess Platform region of China
Authors:Wang, Yuling (1); Li, Jun (1); Bai, Weixia (1)
Author affiliation:(1) College of Agronomy, Northwest A and F University, Yangling, China
Corresponding author:Li, Jun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:107-116
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The semi-humid and prone-to-drought Loess Platform is a typical rain fed agricultural region, in which the planting system is mostly one harvest a year or one harvest two years. Winter wheat and spring maize are main grain crops cultivated in this region. A long-term practice of applying single soil tillage measures in this area causes soil compaction, poor ability of retaining rainwater and providing nutrition. Many studies and practices have demonstrated that reasonable soil rotational tillage systems matching different crop rotation cropping systems played a very important role in maintaining the sustainable development of farmland ecosystem, creating suitable environment (soil, nutrients, water, air, temperature) condition for crop growth and promoting crop yields. In order to investigate the effects of different rotational tillage systems on soil production performance in wheat-maize fields, the soil bulk density, soil porosity, soil nutrients contents, water storages, crop yields and water use efficiency (WUE) as well as economic benefits were determined on the Loess Platform of China, which will provide a theoretical basis to establish a reasonable soil tillage system for a cop rotation system under a certain fertilizing method in the semi-humid and prone-to-drought Loess Platform. A six-year field experiment was carried out from 2007 to 2013 in Dryland Agricultural Research Station, Ganjing Town (latitude 35°33'N; longitude 110°08'E; 900 m above sea level), Shaanxi province. Six kinds of different rotational tillage systems of this experiment included no-tillage/sub-soiling rotation (NT/ST), sub-soiling/ploughing rotation (ST/PT) and ploughing/no-tillage rotation (PT/NT), no-tillage/ploughing/sub-soiling rotation (NT/PT/ST), no-tillage/no-tillage/sub-soiling rotation (NT/NT/ST), ploughing/ploughing/sub-soiling rotation (PT/PT/ST). The continuous no-tillage (CK1), continuous sub-soiling (CK2) and continuous ploughing (CK3) for six years were used as control. Results revealed that, 1) ST/PT was the best to decrease soil bulk density, increase soil porosity, improve soil structure and permeability in six kinds of rotational tillage systems, followed by PT/PT/ST; 2) Comparing with other rotational tillage systems, NT/ST and ST/PT increased the soil organic matter and total nitrogen content significantly in 0-40 cm soil layer, ST/PT and PT/PT/ST increased the available nutrient content apparently; 3) Comparing with other rotational tillage systems, NT/ST and NT/NT/ST got higher soil water storage before sowing, and the same results was founded after harvesting; 4) Considering the overall effects of grain yields, WUE, and economic benefits, ST/PT was the highest, followed by NT/ST, thirdly NT/PT/ST, NT/NT/ST was the lowest. ST/PT increased grain yields by 5.4%-14.1%, WUE by 1.9%-14.1%, economic benefits by 8.2%-22.6%, compared with other rotational tillage systems. NT/ST increased grain yields by 2.8%-8.2%, WUE by 5.7%-11.5%, economic benefits by 5.1%-13.3%, compared with other four rotational tillage systems. In conclusion, appropriate rotational tillage systems are beneficial for protecting soil environment, improving soil structure, retaining soil water, increasing crop yield and economic benefits. sub-soiling/ploughing rotation system (ST/PT) had good production performance in reducing soil bulk density, improving soil structure, promoting soil increasing water storages and soil nutrients contents, promoting crop yields and WUE, which is more suitable soil rotational tillage system in winter wheat and spring maize rotation fields. No-tillage/sub-soiling rotation system (NT/ST) could increase rainwater infiltration, protect soil, and enhance water reserving and soil moisture keeping, and its crop yields and economic benefits were only inferior to ST/PT. Hence, NT/ST was also a good soil rotational tillage system in this region. Considering the local conditions, ST/PT could be recommended as suitable soil tillage patterns to match the "one crop one year" crop rotation system, followed by NT/ST. These two systems can be employed to achieve better production performance on the basis of the specific situation. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Soils
Controlled terms:Agricultural machinery - Agriculture - Crops - Cultivation - Drought - Economic and social effects - Ecosystems - Grain (agricultural product) - Harvesting - Moisture - Nutrients - Porosity - Rotation - Sea level - Sediments - Soil conservation - Soil mechanics - Soil moisture - Sustainable development - Water supply
Uncontrolled terms:Agricultural research - Crop rotation system - Loess Platform - Production performance - Rainwater infiltrations - Soil organic matters - Tillage system - Total nitrogen content
Classification code:444 Water Resources - 446.1 Water Supply Systems - 454.3 Ecology and Ecosystems - 471.1 Oceanography, General - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 801.4 Physical Chemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2015.01.016
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 7>
Accession number:20151000594721
Title:Characteristics of backflow vortex cavitation in screw centrifugal pump
Authors:Deng, Yuxuan (1); Li, Rennian (1); Han, Wei (1); Yang, Wenjie (1); Li, Zhenggui (1); Zhang, Yipeng (1)
Author affiliation:(1) School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China
Corresponding author:Li, Rennian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:86-90
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Screw centrifugal pump has swirling backflow under a wide range of flow rates. The backflow vortex structure occurs in the shear layer between the main flow and the swirling backflow. The pressure at the core of a backflow vortex is lower than the ambient pressure due to the centrifugal force on the vertical flow which results in cavitation if the core pressure becomes lower than the vapor pressure. This is called backflow vortex cavitation. In order to study the backflow vortex cavitation, a screw centrifugal pump was designed for experimental studies. The clearance between vane rim and cover plate was 2.9 mm in this screw centrifugal pump. By using the high speed video picture, we observed two backflow vortex cavitation clouds extending upstream from the tip at the screw centrifugal pump inlet, covering a wide range of flow rates. We also found that under a certain net positive suction head (NPSH), i.e., when the flow rate was decreased, the volume of the two backflow vortex cavitation cloud was decreased. Experimental studies on the backflow vortex cavitation from this screw centrifugal pump have provided novel insight of the characteristics of backflow vortex cavitation, but the limited information has not lead to the complete understanding of the phenomena. In addition to blade surface and backflow vortex cavitations, tip leakage cavitation occurred for screw centrifugal pump with tip clearance. With these types of cavitation, the flow in a screw centrifugal pump presented a very complicated three-dimensional structure. Since experiment results give limited information, numerical simulation plays an important role to further understand such complicate flow phenomena. Using the CFD code, the fundamental characteristics of the backflow vortex cavitation was investigated in detail. It was found that the backflow vortices were formed in a circumferentially twisted manner at the boundary between the swirling backflow and the straight inlet flow. When the flow rate was decreased, the screw centrifugal pump inlet flow velocity increased, but the static pressure of fluid at screw centrifugal pump inlet region decreased. As the screw centrifugal pump inlet fluid static pressure was decreased, the static pressure of suction side of vane region near by vane tip at screw centrifugal pump inlet decreased. Meanwhile, the pressure of pressure side of vane region near by vane tip at screw centrifugal pump inlet was about vapor pressure. With the decreased flow rate, the pressure difference of pressure side of vane and suction side of vane reduced. The backflow region reduced upstream due to the decreased pressure difference of pressure side of vane and suction side of vane, which is the main reason of the two backflow vortex cavitation volume decreased with the flow rate decreased in screw centrifugal pump. When the clearance between vane rim and cover plate was less than 1.3 mm in the screw centrifugal pump, the screw centrifugal pump inlet region had no backflow occurred. It indicated that the size of clearance between vane rim and cover plate have influences on backflow vortex cavitation occurred in screw centrifugal pump inlet. The purpose of the present study is to obtain a further understanding of backflow vortex cavitation. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Vortex flow
Controlled terms:Cavitation - Centrifugal pumps - Computational fluid dynamics - Computer simulation - Flow rate - Flow velocity - High speed cameras - Hydrodynamics - Hydrostatic pressure - Inlet flow - Plates (structural components) - Pumps - Screws - Shear flow
Uncontrolled terms:Backflow - Fundamental characteristics - Limited information - Net positive suction heads - Pressure differences - Screw centrifugal pumps - Three-dimensional structure - Tip leakage cavitation
Classification code:408.2 Structural Members and Shapes - 605 Small Tools and Hardware - 618.2 Pumps - 631 Fluid Flow - 723.5 Computer Applications - 742.2 Photographic Equipment
DOI:10.3969/j.issn.1002-6819.2015.01.013
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 8>
Accession number:20151000594714
Title:Parameters optimization and experiment of garlic picking mechanism
Authors:Yu, Zhaoyang (1); Hu, Zhichao (1); Wang, Haiou (1); Peng, Baoliang (1); Xie, Huanxiong (1); Wu, Feng (1)
Author affiliation:(1) Nanjing Research Institute of Agricultural Mechanization, Ministry of Agriculture, Nanjing, China; (2) Key Laboratory of Modern Agricultural Equipment, Ministry of Agriculture, Nanjing, China
Corresponding author:Hu, Zhichao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:40-46
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the present, the mechanized harvest technology of garlic in China is still in infancy. Most of the current domestic garlic harvesters only can accomplish the processes of digging and laying. However, the garlic combine harvester, which can synchronously finish the processes of digging, cleaning soil, cutting stem, cutting beard, gathering garlic bulb, etc., is still under test and demonstration. Furthermore, picking is the most important and difficult process of combine harvest, because the bad separation will result in another manual cutting. Different with the harvest mode of the developed countries, the farmers in China pull out the young garlic shoot in its early stage, which causes the garlic to collapse and affects its locating in the application of half feeding combine harvest. Besides, the residual stem is long, the damage rate is high and the cut pass rate is low. In view of the above problems, a picking device of garlic combine harvester was designed, realizing the garlic plant flexibly clamped, the garlic being sorted one by one and aligned automatically. In order to further study the garlic picking device, the garlic picking testbed was designed. The garlic picking testbed consists of a garlic picking device, shelf and transmission system. The main goal of testbed is the garlic picking device which consists of a clamping device, a rank-alignment device, a cutting device. In order to enhance operational performance of garlic picking device, reduce the residual stem length, the damage rate and increase cutting surface pass rate, the Box-Benhnken central composite experimental design principle was conducted in this paper. A four factors and three levels response surface experiment was completed on the garlic picking testbed, with four factors which affect picking quality. This paper established the response surface model and studied the factors affecting picking quality. At the same time, it synthetically optimized the factors affecting picking quality. The results showed that trial factors had great effects on picking quality. The significant effects of clamp number, main chain speed, clamp height, and clamp angle on residual stem length were in a decreasing order; The significant effects of main chain speed, clamp number, clamp height, and clamp angle on damage rate were in a decreasing order; The significant effects of main chain speed, clamp number, clamp height, and clamp angle on cut pass rate were in a decreasing order. The higher main chain speed, higher clamp height, more numbers of plants, then the residual stem length was longer, in contrast, the residual stem length was shorter. The higher main chain speed, shorter clamp height, more numbers of plants, then the damage rate was higher, in contrast, the damage rate was lower. The lower main chain speed, higher clamp height, less numbers of plants, then the cut pass rate was higher, in contrast, the cut pass rate was lower. The interaction of various factors affecting residual stem length, damage rate and cut pass rate were not significant changed. The optimum parameters were that the speed of main clamping chain was 1.05 m/s, the clamping angle was 77°, the clamping height was 220 mm, and the clamping number was two. The results have provided a base for the garlic picking mechanism. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Speed
Controlled terms:Agricultural machinery - Agriculture - Chains - Clamping devices - Combines - Harvesters - Harvesting - Optimization - Separators - Surface properties - Testbeds
Uncontrolled terms:Combine harvesters - Developed countries - Operational performance - Optimum parameters - Parameters optimization - Picking - Response surface modeling - Transmission systems
Classification code:602.1 Mechanical Drives - 605 Small Tools and Hardware - 723.5 Computer Applications - 802.1 Chemical Plants and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques - 931.1 Mechanics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.006
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 9>
Accession number:20151000594717
Title:Design of test platform for robot flexible grasping and grasping force tracking impedance control
Authors:Wang, Xuelin (1); Xiao, Yongfei (1); Bi, Shuhui (1); Fan, Xinjian (1); Rao, Honghui (2)
Author affiliation:(1) Shandong Provincial Key Laboratory of Robot and Manufacturing Automation Technology, Institute of Automation, Shandong Academy of Sciences, Jinan, China; (2) School of Engineering, Jiangxi Agricultural University, Nanchang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:58-63
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:One of the major challenges of agricultural robots is the grasping and picking fresh fruit and vegetable without any damage under the complex environment. In order to minimize the harm due to robot grasp, this paper mainly introduces a dexterous multisensory gripper design and also develops a new force impedance control algorithm. First, the gripper with dual motor drive was designed, and each of fingers had an independent servo drive system and was integrated with force and tactile sensors. The calibration force sensors were mounted at the root of each finger, and the force signals were obtained by the force sensors. The expected force, position and speed parameters of the fingers can be set separately, so the grip centre and stroke can be controlled for the finger by pre-programming, the movement and forces of grasped objects can be actively controlled to achieve through the two-finger operations. The gripper with both the mechanical mechanism and control flexibility was mounted in the end of the industrial robot. The grasping experiment platform composed of industrial robot and dexterous gripper integrated monocular vision, force sensing and many kinds of sensors. The 2-D vision was able to quickly detect and locate grasped objects at the top of the experiment platform. Second, a force impedance control algorithm was proposed and used for one of fingers, position control was used for another finger, and it can regulate the grasping force by dening the target impedance between desired position and contact force. The whole grasping system can be equivalent to impedance & admittance model, and the finger force/position control can be equivalent to the expected target inertia-damping-stiffness model, and the model parameters can be adjustable according to the needs to realize the dynamic relationship between grasping force and position. The contact force errors between expected force value and actual force acquired from the force sensor were as the input of impedance controller and its output can be realized by the reference trajectory correction to the internal position control loop. The proposed algorithm only considered the direction of gripping fruit and vegetable, and the reference trajectory can be determined simply, and then avoids the use of complicated impedance control for multi-degree of freedom manipulators, through which it can improve the real-time control and robustness of the grasping system with model uncertainty or external force disturbance. Robot grasping experiments show that the system runs smoothly and reliably, the force-feedback impedance control is very effective, and the steady state error is maximum range within ± 0.4N in the experiment of grasping the tomatoes and eggs. It can make force track value with small force overshot and fast response simultaneously between the end-effector and fruit and vegetable, so it makes the force controller adaptive to the dynamic grasp process between the end-effector and fruit and vegetable, it can realize the flexible grasping and reduce damages and ensure the quality of the grasped fruit and vegetable. The research provides a key control technology for the compliant grasping of fruit and vegetable. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:13
Main heading:Position control
Controlled terms:Algorithms - Controllers - Degrees of freedom (mechanics) - Dynamics - Electric drives - End effectors - Feedback - Force control - Fruits - Grippers - Industrial robots - Machine design - Navigation - Real time control - Robot learning - Robots - Servomotors - Ultrasonic devices - Uncertainty analysis - Vegetables
Uncontrolled terms:Admittance control - Flexible grasping - Force/position control - Fresh fruit and vegetables - Impedance control - Multi degree-of-freedom - Picking - Reference trajectories
Classification code:601 Mechanical Design - 705 Electric Generators and Motors - 716.3 Radio Systems and Equipment - 723 Computer Software, Data Handling and Applications - 731 Automatic Control Principles and Applications - 732 Control Devices - 732.1 Control Equipment - 753.2 Ultrasonic Devices - 821.4 Agricultural Products - 921 Mathematics - 922.1 Probability Theory - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.009
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 10>
Accession number:20151000594743
Title:Spatial-temporal characteristics of cultivated land in Tibet in recent 30 years
Authors:Yang, Chunyan (1); Shen, Weishou (2); Wang, Tao (1)
Author affiliation:(1) Nanjing University of Information Science and Technology, Nanjing, China; (2) Nanjing Institute of Environmental Sciences, Ministry of Environmental Protection, Nanjing, China; (3) Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology, Nanjing, China
Corresponding author:Shen, Weishou
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:264-271
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cultivated land plays a vital role in ensuring food safety and promoting social and economic development. At the same time, ecological environment in Tibet is fragile. Therefore, an in-depth understanding of the changing process of cultivated land will provide reference information for agricultural development and ecological security in Tibet. In this paper, based on remote sensing images of four periods and other related data, the temporal-spatial characteristics of cultivated land area in Tibet from 1980 to 2010 was analyzed. By using ERDAS IMAGE9.3 software, the remote sensing images were registered and geometrical corrected based on topographic maps of 1:100000 scale. According to the remote sensing image shape, texture and color, combined with land use status data, remote sensing interpreting marks were established. The supervised classification of automatic interpretation method was used to gain interpretation result, from which data of cultivated land were extracted. After correcting the interpretation cultivated land results combined with field investigation data and visual interpretation of remote sensing images, cultivated land area's identifiable information of four periods were gotten. In order to preferably understand the temporal and spatial changes of cultivated land, the study period was evenly divided into three time periods: the first stage was 1980-1990, the second stage was 1990-2000, and the third stage was 2000-2010; and the units including administrative region, interval of altitude as well as latitude were divided. By using dynamic degree of land use, location index of land use, the temporal-spatial characteristics of cultivated land area were analyzed. Analysis of different conversion types showed that the increase of cultivated land was mainly from grassland and forest land, while the decreased cultivated land mainly was converted to grassland, forest land and construction land. From the climatic conditions, the period of 1990-2010 was beneficial to expand the cultivated land, and cultivated land in Tibet also showed a faster growth rate. The implementation of the western development strategy sped up the development of social economy in Tibet, also brought the building occupancy and ecological restoration, and therefore the cultivated land has decreased. Results showed that: 1) Between 1980 and 2010 cultivated land increased by 451 km<sup>2</sup>, from 3252 km<sup>2</sup> to 3703 km<sup>2</sup>, and its proportion to the total area of the Tibet increased from 0.27% to 0.31%, with an annual change rate of 0.46% and an annual variation of 15.37 km<sup>2</sup>. 2) Cultivated land in Tibet was mainly distributed in four regions, i.e., Shigatse, Lhasa, Chamdo and Lhoka, and distributed in the altitude range of 3200-4200 m and the latitude range of 26°-33°N, of which, Lhasa, 3800-4000 m altitude and zone of 29°-30°N were the regions that cultivated land centered most. 3) Cultivated land expanded to higher altitude and lower altitude areas. Chamdo, the altitudes over 4200 m and lower than 3200 m and the zone of 30°-33°N increased most rapidly in area of cultivated land. It was the comprehensive effect of natural conditions and human activities, and produced the result of temporal and spatial changes characteristics of cultivated land in Tibet in recent 30 years. The special geographical environment and ecological function of Tibet had decided that in the conditions of climate warming, the impact of human activities on cultivated land must be fully understood, the consciousness of cultivated land protection should be raised; and scientific planning and reasonable use of cultivated land should be achieved so as to improve the land use efficiency and supply capacity. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Land use
Controlled terms:Dynamics - Ecology - Economic and social effects - Economics - Forestry - Image reconstruction - Maps - Planning - Remote sensing
Uncontrolled terms:Cultivated lands - Social and economic development - Spatial-temporal characteristics - Supervised classification - Temporal and spatial changes - Temporal and spatial variation - Temporal-spatial characteristics - Tibet
Classification code:403 Urban and Regional Planning and Development - 454.3 Ecology and Ecosystems - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 821.0 Woodlands and Forestry - 902.1 Engineering Graphics - 931.1 Mechanics - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2015.01.035
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 11>
Accession number:20151000594725
Title:Hydrodynamic characteristics of tapered spoilbank under simulated rainfall condition
Authors:Wang, Xuesong (1); Xie, Yongsheng (1)
Author affiliation:(1) Institute of Soil and Water Conservation, Northwest Agricultural and Forestry University, Yangling, China; (2) Institute of Soil and Water Conservation, Chinese Academy of Science, Ministry of Water Resources, Yangling, China
Corresponding author:Xie, Yongsheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:117-124
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil erosion newly derived from engineering spoilbank severely threatens ecological safety of construction sites and surrounding areas. Engineering spoilbank with three-dimensional is quite different from the traditional slope, as a result, to study the hydrodynamic process of a three-dimensional engineering spoilbank is of great necessity. In this study, in order to find the best hydrodynamic parameters that can describe the hydrodynamic process of soil erosion caused by tapered engineering spoilbank, laterite collected from the north area of Jiangxi province was selected as the main test material and variations in hydraulic parameters (flow shear stress, stream power, unit stream power, unit energy of water-carrying section) of overland flow were studied experimentally. This study was processed in inner-door rainfall experimental condition. Three kinds of artificial intensities (1.0 mm/min, 1.5 mm/min, 2.0 mm/min) and three gravel content (10%, 20%, 30%) were designed. Every experiment persisted 33 min when there was no erosion gully occurring on the surface of the tapered engineering spoilbank. The result shows that: 1) instantaneous value and average value of independent hydrodynamic parameter were closely related to soil detachment rate except the cross-section specific energy. To be more specific, both the flow shear stress and the instantaneous flow shear stress had a significant power function relation with the corresponding detachment rate and this relationship also occurred between the stream power and the detachment rate, while, the relationship between unit stream power (or the instantaneous unit stream power) and the detachment rate (or the instantaneous detachment rate) was linear. In terms of the cross-section specific energy, its instantaneous value had no obvious relations with the instantaneous detachment rate though its average value had a power function with the average detachment rate; 2) critical unit stream power for surface erosion of the tapered spoilbank was 6.8×10<sup>-3</sup> m/s, and the critical instantaneous value of surface erosion parameter tended to be less 3.8×10<sup>-3</sup> m/s. Moreover, the erodibility parameter of experimental material was about 0.0053-0.0059 s<sup>2</sup>/m<sup>2</sup>, and that was 20-30 times larger than the pure clay. So, soil mixed with gravel on the spoillbank surface was more easily carried away by the overland flow than the pure clay with no stirred; 3) the relevance between the instantaneous cross-section specific energy and the instantaneous detachment rate was extremely low (R<sup>2</sup>=0.130), so instantaneous cross-section specific energy was not suitable to be a hydrodynamic parameter describing the hydrodynamic process of soil erosion caused by tapered engineering spoilbank; 4) according to values of fitting effect, the parameters tested should be ranked in the order of stream power>instantaneous stream power>unit stream power>flow shear stress>instantaneous unit stream power>instantaneous flow shear stress>cross-section specific energy, obviously stream power had the best correlation (power function) with the soil detachment rate (R<sup>2</sup>=0.972). So stream power was the best one of all the hydrodynamic parameters tested to describe the hydrodynamic process of soil erosion caused by tapered engineering spoilbank. Stream power tends to be more scientific to study the erosion process of tapered engineering spoilbank on the energy hand. In summary, the hydrodynamic process of a tapered engineering spoilbank is quite different from that of a slope. The result obtained may lay the foundation for the establishment of process-based model of soil erosion caused by engineering spoilbank, and provide a scientific guidance for comprehensive control of soil and water loss in production and construction areas. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Soil conservation
Controlled terms:Erosion - Fluid dynamics - Gravel - Hydrodynamics - Rain - Shear flow - Shear stress - Soils
Uncontrolled terms:Cross-section specific energies - Experimental conditions - Experimental materials - Hydraulic parameters - Hydrodynamic characteristics - Hydrodynamic parameters - Tapered engineering spoilbank - Three-dimensional engineering
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 421 Strength of Building Materials; Mechanical Properties - 443.3 Precipitation - 483 Soil Mechanics and Foundations - 631.2 Hydrodynamics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.017
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 12>
Accession number:20151000594710
Title:Design and experiment of pneumatic cylinder-type precision direct seed-metering device for rice
Authors:Zhang, Shun (1); Xia, Junfang (1); Zhou, Yong (1); Zhai, Jianbo (1); Guo, Yangmin (1); Zhang, Xiumei (1); Wu, Hao (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan, China
Corresponding author:Xia, Junfang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:11-19
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the adjustment of social industrial structure and the rising cost of rural labor, especially the lack of freshwater resources, rice direct seeding is characterized by cost-saving advantages compared to rice transplanting. The planting area of rice direct seeding is enlarged during the last several decades. In order to meet the direct seeding requirements (2-4 seeds per hole) of hybrid rice, a unique pneumatic cylinder-type precision metering device was designed, which combined the features of socket-filling, vacuum suction, air-blowing, rubber guard and pneumatic clear plugging. This paper described the working principle of metering device, determined the key structure parameters, and established the mechanical model of single rice seed during the air-blowing clearing process of air nozzle. Based on pre-experiments, the socket shape, cylinder speed, vacuum degree, and air-blowing strength were the main impact factors of the metering device performance. In bench test, the hybrid rice bud seed Huanghuazhan, which had been pre-germinated with the moisture content of 21.65%-23.73% (wet basis), was selected as experimental material and the effects of the four main impact factors on miss-seeding rate, qualified rate and reseeding rate of seeding were studied by four factors and three-level orthogonal experimental design. The results indicated that the order affecting miss-seeding rate (less than 2 seeds per hole), qualified rate (2-4 seeds per hole) and reseeding rate (more than 4 seeds per hole) was socket shape>cylinder speed>air-blowing strength>vacuum degree. The optimal combination parameters were conical socket shape, cylinder speed with 10 r/min, air-blowing strength with 17.03 m/s and vacuum degree with 4 kPa. Under the condition of the optimal combination parameters, the miss-seeding rate, qualified rate and reseeding rate were 3.6%, 85.47% and 10.93%, respectively. Meanwhile, the cavity rate was 0.4%, the average hole distance was 199.37 mm (theoretical hole distance was 200 mm), the variation coefficient of hole distance was 6.1%, the seed breakage rate was 1.08% and the seeding quality meet the precise direct seeding requirements of hybrid rice. The seeding adaptability experiment was carried out under the same conditions with three hybrid rice bud seeds (Gangyou 364, Shanyou 63 and Fengyuanyou 272), whose overall dimension existed some differences from each other. All the miss-seeding rates were less than 4%, all the qualified rates were more than 85.07%, all the cavity rates were less than 0.67%, the average hole distances were 200.51, 200.48 and 200.07 mm, respectively; the variation coefficient of hole distances were 4.46%, 4.61% and 5.67% respectively, the seed breakage rates were 0.67%, 0.34% and 0.64%, respectively. Experiment results indicated that when planting different hybrid rice, the conical socket had a certain adaptability with the auxiliary of flexible seed clearing rope and seed clearing air nozzle. Although the seeding performance should be further improved, the miss-seeding and cavity rates were lower, the seed breakage rates were small, the suctions were never plugged, which indicated that the features of metering device had extensive application prospect. The research provides a theoretical reference for the design of socket-type precision direct seed-metering device for rice. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Seed
Controlled terms:Agricultural machinery - Cylinders (shapes) - Design - Design of experiments - Nozzle design - Nozzles - Pneumatic drives - Pneumatic equipment - Pneumatic materials handling equipment - Pneumatics - Rope - Structural design
Uncontrolled terms:Air nozzles - Direct seeds - Experimental materials - Fresh water resources - Industrial structures - Orthogonal experimental design - Socket - Variation coefficient
Classification code:408 Structural Design - 535 Rolling, Forging and Forming - 631.1 Fluid Flow, General - 632.3 Pneumatics - 632.4 Pneumatic Equipment and Machinery - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research
DOI:10.3969/j.issn.1002-6819.2015.01.002
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 13>
Accession number:20151000594746
Title:Effect of plant growth regulator on electrical impedance spectroscopy during ripening process in kiwifruits
Authors:Li, Xingshu (1); Xu, Gang (1); Huang, Lei (1); Zhang, Zhiwei (3); Yue, Tianli (3)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, China; (2) Shaanxi Engineering Research Center for Agricultural Equipment, Yangling, China; (3) College of Food Science and Engineering, Northwest A and F University, Yangling, China; (4) College of Food Science and Engineering, Qingdao Agricultural University, Qingdao, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:288-293
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plant growth regulators were used frequently to improve the yield of kiwifruits in recent years. But the use of plant growth regulators often caused low internal quality and deformity of fruits, and the expanded kiwifruits easily decay after softening. It is necessary to explore the effect of plant growth regulators on kiwifruit tissue during the ripening process. Up to now, the traditional chemical methods and the other modern techniques such as NIR, FTIR and NMR have been adopted to analyze the influence of plant growth regulators on fruit tissues. But these approaches are difficult to achieve fast and cheap measurement. Electrical impedance spectroscopy (EIS) is a fast developing method in analyzing materials' characterization. When currents with different frequencies flow through the biological tissue, cytomembrane, the extracellular and intracellular fluid would show different electrical properties. Therefore, EIS has the potential to be used for detecting the change of kiwifruit cell microstructure during the ripening process. To develop a quick, convenient and economic method for exploring the effect of plant growth regulators on kiwifruit fruit, EIS technique was used to analyze the change of biological tissue at cellular level during the ripening process of the expanded and control kiwifruits by using an equivalent electrical circuit. Hayden model was chosen to analyze kiwifruit ripening process, which is composed of extracellular resistance, intracellular resistance and constant phase element representing the cytomembrane. Complex nonlinear least square (CNLS) method was used for fitting the EIS data and determining the parameters of Hayden model. The results indicated that the impedance magnitude of the expanded and control fruits decreased with increasing frequency, and impedance magnitude decreased with kiwifruit ripening only at low frequencies. It was obvious during the ripening process that the impedance of control fruits decreased more quickly than that of the expanded fruits. The phase angles of two types of kiwifruits increased sharply and then decreased quickly with the increase of frequency, and reached the maximum values at 12 kHz. Cole-cole plots of kiwifruit tissues presented the semicircles with different radiuses, which represent the characteristics of typical biological tissue. Cytomembrane impedances of expanded kiwifruits changed minimally during the ripening process of 15 days, but after 7 days, cytomembrane impedances of the control fruits dropped sharply. Extracellular fluid resistance of two types of kiwifruits initially decreased, then increased and finally decreased with ripening process. Extracellular fluid resistance of expanded fruits was larger than that of control fruits, and extracellular fluid resistance of control fruits dropped more quickly than that of expanded fruits after 7 days. Variation of intracellular fluid resistance of two types of kiwifruits was not obvious. Because plant growth regulator could alleviate the damage of cell membrane, EIS properties of two types of kiwifruits were different. So electrical impedance spectroscopy is useful for the identification of expended kiwifruits from untreated kiwifruits by impedance properties. Consequently use of EIS to analyze the ripening process provides a technological foundation for the detection of expanded fruits. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Fruits
Controlled terms:Body fluids - Cell membranes - Chemical analysis - Cytology - Electric impedance - Electric impedance measurement - Electric network analysis - Enzyme activity - Fourier transform infrared spectroscopy - Growth kinetics - Histology - Least squares approximations - Mobile security - Spectroscopy - Tissue - Tissue engineering
Uncontrolled terms:Electrical impedance - Kiwifruits - Plant growth regulators - Plants - Ripening process - Storing
Classification code:461 Bioengineering and Biology - 701.1 Electricity: Basic Concepts and Phenomena - 703.1.1 Electric Network Analysis - 801 Chemistry - 804 Chemical Products Generally - 821.4 Agricultural Products - 921.6 Numerical Methods - 942.2 Electric Variables Measurements
DOI:10.3969/j.issn.1002-6819.2015.01.038
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 14>
Accession number:20151000594713
Title:Design of planting mechanism for garlic planter
Authors:Xie, Xuehu (1); Zhang, Yong (1); Liu, Zhao (1); Cheng, Yongjian (2); Liu, Caixia (1); Bi, Ligetu (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Hohhot, China; (2) Qingdao Engineering Machinery Co., LTD, Qingdao, China
Corresponding author:Zhang, Yong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:34-39
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Garlic planters developed relatively late and its technology is not matured in the agricultural machinery. However, due to the growing demand for garlic, intensive planting of garlic has become the trend in modern agriculture. The restricting factor of garlic intensive planting is delayed garlic planting machinery development. This paper proposed two key problems of developing garlic planting machinery: garlic cloves insert vertically and the cloves face towards consistent. To solve these two problems, we designed a garlic planting mechanism which can meet the garlic agricultural cultivation requirement. Based on the study of garlic planter at home and abroad, we designed a mechanism and analyzed it in detailed according to the shape characteristics of garlic cloves. The software of Solidworks was used for modeling the mechanism and the parts were printed by 3D printer, and then the garlic cultivation mechanism was built and tested. The test bench includes mobile platform which can control the speed, stepper motor, garlic planting mechanism, bracket, soil and 10 different sizes of garlic cloves. The garlic cultivation mechanism is fixed on the mobile platform through the bracket and steeper motor is fixed on the mobile platform. The rope of garlic cultivation mechanism is winded up onto the stepper motor. Stepper motor drives the rope of garlic planting mechanism to move with the mobile platform movement and press garlic cloves into the soil. By changing the frequency of the stepper motor and the speed of the mobile platform, we observed the angle between bulbil and soil of different sizes of garlic cloves under different combination of frequency and speed variation. The experimental data showed that changing the mobile platform movement speed had little effect on the angle between cloves bulbil and the soil when the frequency of variable frequency motor was fixed. When the mobile platform movement speed was fixed, changing the frequency of variable frequency motor also had little impact on the angle. While changing the angle between the garlic planting mechanism and the ground, it had large effect on the angle. Using this planting mechanism can not only ensure the garlic camber surface toward consistently but also reduce the effect on the vertical degree of garlic cloves caused by the speed of planter. But the different sizes of garlic had a pronounced impact on this plant mechanism and need to be further optimized. When cloves insert into the soil, the garlic planting mechanism basically had no damage to cloves. This design adopts a brand-new concept and provides a new approach for designing garlic planting mechanism. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:15
Main heading:Mechanisms
Controlled terms:3D printers - Agricultural machinery - Agriculture - Crops - Cultivation - Design - Digital storage - Electric drives - Experiments - Fixed platforms - Machine design - Mobile phones - Rope - Software testing - Soils - Speed - Stepping motors - Variable speed drives
Uncontrolled terms:Agricultural cultivation - Cultivation mechanisms - Garlic planter - Machinery development - Modern agricultures - Restricting factors - Shape characteristics - Variable frequency motors
Classification code:408 Structural Design - 483.1 Soils and Soil Mechanics - 511.2 Oil Field Equipment - 535 Rolling, Forging and Forming - 601 Mechanical Design - 601.3 Mechanisms - 705 Electric Generators and Motors - 718.1 Telephone Systems and Equipment - 722.1 Data Storage, Equipment and Techniques - 723.5 Computer Applications - 745.1.1 Printing Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.005
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 15>
Accession number:20151000594749
Title:Fermentation process and bioactivity of peptides prepared from fermented goat placenta residues
Authors:Hou, Yinchen (1); Zhou, Jiejing (1); Liu, Wangwang (1); Cheng, Yongxia (1); Wu, Li (1); Zhu, Xiaohua (1); Bai, Yongliang (1); Yang, Gongming (1)
Author affiliation:(1) College of Food Science, South China Agricultural University, Guangzhou, China
Corresponding author:Yang, Gongming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:311-316
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Goat placenta has been used in Chinese traditional medicine, and the latest studies have demonstrated that it is an animal recourse rich in biological and therapeutic components. At present, the water-soluble immune active peptides were extracted as health care ingredient and so on, and the rest was used to prepare bioactive peptides. Bioactive peptides have been defined as specific protein fragments that have a positive impact on body functions or conditions and may ultimately influence health. The preparation of goat placenta peptides by using enzymatic hydrolysis has been carried out. Nevertheless, little information is available for its immune activity of the hydrolysates, and little information is known about goat placenta peptides prepared by fermentation. In this article, the goat placenta residues were fermented by using Bacillus subtilis to prepare bioactivity peptides. During the fermentation process, the activity of protease, the average chain length of polypeptides, immunoactivity and the antioxidant activity of fermentation broth were investigated. The results revealed that as fermentation time was prolonged, the degree of hydrolysis of goat placenta residues and the activity of protease gradually increased and the average chain length of polypeptides decreased. The immunoactivity and antioxidant activity of fermentation broth increased at first and then reduced. At fermentation of 30 h, the DPPH radical scavenging capacity of fermentation broth reached 87.16%; however, the fermentation broth showed the best effect on proliferation of mouse spleen lymphocytes with fermentation time at 35 h. It can be seen that the surface of the goat placenta residues after fermentation displayed rough and appeared more holes and small particles. The result showed that the goat placenta residues were eroded by the bacteria and its metabolites. The immune and antioxidant activity of fermentation broth were closely depending on the concentration of protein, the EC<inf>50</inf> values on hydroxyl radical scavenging activities at 0.667mg/mL. At fermentation with 35 h, the fermentation broth was ultra-filtrated through membranes with different molecular weight cut-off (MWCO). The immunoactivity and antioxidant activity of different fractions were measured. It was found that peptides in the range of >3-10 kDa mainly accounted for the immune activity and peptides in the range of ≤3 kDa mainly accounted for the antioxidant activity. There are certain correlation between the bioactivity of goat goat placenta peptides and its molecular weight. It is recognized that, due to their lower molecular mass, peptides can be more reactive than those with higher Mw, and the bioactivity ability of peptides is also related to the material characteristics, restricted enzyme sites and its space structure. This finding is in agreement with previous studies, which support the fact that the bioactivity ability of peptides is related to molecular mass. Goat placenta has a great potential of supplying peptides. Bioactive peptides can be incorporated in the form of ingredients in functional and novel foods, dietary supplements and even pharmaceuticals with the purpose of delivering specific health benefits. Bioactive peptides derived from goat placenta offer a promising approach for the promotion of health by means of a tailored diet and provide interesting opportunities to the food industry. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Proteins
Controlled terms:Antioxidants - Bacteriology - Bioactivity - Chain length - Chains - Dietary supplements - Enzymatic hydrolysis - Enzymes - Fermentation - Free radicals - Hydrolysis - Molecular mass - Molecular weight - Nutrition - Peptides - Plants (botany) - Process control
Uncontrolled terms:Anti-oxidant activities - Bacillus subtillis - Chinese traditional medicine - Dpph radical scavenging capacities - Goat placenta residues - Immunoactivity - Material characteristics - Molecular weight cutoff
Classification code:461.6 Medicine and Pharmacology - 461.9 Biology - 602.1 Mechanical Drives - 731 Automatic Control Principles and Applications - 801 Chemistry - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 822.3 Food Products
DOI:10.3969/j.issn.1002-6819.2015.01.041
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 16>
Accession number:20151000594733
Title:Remote sensing image fusion based on high-balanced multi-band multiwavelet packet transform
Authors:Wang, Haijiang (1); Wang, Zhoulong (2); Li, Lihong (1); Ma, Yongqiang (1)
Author affiliation:(1) School of Information and Electrical Engineering, Hebei University of Engineering, Handan, China; (2) College of Geography and Planning, Ludong University, Yantai, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:178-186
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The article proposes high-order balanced multi-band multiwavelet packet transforms and the remote sensing image fusion based on the transforms for improving the performances of wavelet transforms based remote sensing image fusion. The properties of different wavelet transforms and the relationship among them were firstly analyzed. It was shown that although the balanced multi-band multiwavelet transform had improvements in signal processing due to the properties of balancing and multi-band systems, it should be developed to its wavelet packet counterpart for more effective spatial-frequency domain representation and further improvement in application. Then, the principle theory of the high-order multi-band multiwavelet packet transform was analyzed and it was found the library of the base functions of the transform is an M-fold tree structure (M is the band number of a wavelet system). The fast algorithms of the decomposition and reconstruction of the transform were presented. With the algorithm, one could obtain the transform-domain coefficients in different frequency bands of an analyzing dataset. Correspondingly, the library constituted by these coefficients could be also viewed as a set with M-fold tree structures. Using a tree-information searching algorithm based on cost functions, one could find the most suitable sub-tree library in such a tree-structure set. Based on the coefficients corresponding to the library, the high-order balanced multiwavelet packet transform, which was more suitable to the dataset, could be established. Next, the remote sensing image fusion method based on the transform scheme was constructed. An existing simple fusion strategy was used to construct the wavelet transform based fusion method so as to present a clear evaluation on the function of wavelet transforms. The fusion strategy integrated the intensity-hue-saturation (IHS) transform and wavelet transform together. The IHS transform was used to obtain the intensity component of the multi-spectral images in a remote sensing image dataset. After that, the obtained intensity component and the panchromatic band in the dataset were both decomposed at different levels by the high-order multi-band multiwavelet packet transform, and the coefficients corresponding to different frequency bands were then generated. After the most suitable coefficient sub-tree library for the dataset was obtained, the low and relatively high frequency coefficient parts in the library were then merged with average fusion rule and maximum fusion rule respectively. After performing the reconstruction of the proposed transform on the merged coefficient, the merged intensity component was obtained. Finally, the fusion image could be generated after an inverse IHS transform. With this fusion strategy, this paper comparatively evaluated the performance of the high-order balanced multi-band multiwavelet packet transform based fusion method and other traditional wavelet packet transform based fusion methods. In the experiment, these methods were applied to the image fusion between the panchromatic bands and multi-spectral bands of the datasets received from different satellites, such as Chinese Resource Satellite and Landsat-7 Satellite. These datasets containing rich textures and spectral information, could present an effective analysis. The experimental result showed that for different band number M, the proposed method generally gains the best fusion result when balance order ρ equals to 2, and in different balance order ρ, the proposed method with band number 3 obtains the best result in most experimental dataset cases. Also, it showed that in general, the suitable decomposition level for the proposed method is 2 or 3.Moreover, it was found that with a suitable balanced order and band number, the proposed method could provide improvements in both visual quality and objective evaluation compared with traditional fusion methods. Especially, it could reduce both the average spectral error and relative global dimensional synthesis error by more than 3 percent compared with traditional methods. Also it incurred reasonable computational complexity compared with traditional methods. The method is thus useful for remote-sensing image fusion. Furthermore, it is also advantageous for many other image processing tasks, such as texture extraction and edge detection. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Wavelet transforms
Controlled terms:Algorithms - Cost functions - Edge detection - Forestry - Frequency bands - Frequency domain analysis - Function evaluation - Image fusion - Image processing - Image reconstruction - Packet networks - Quality control - Remote sensing - Satellites - Signal processing - Spectroscopy - Textures - Trees (mathematics)
Uncontrolled terms:Balanced multiwavelets - Decomposition and reconstruction - High-order - Intensity hue saturations - Multi-wavelet transform - Multi-wavelets - Spatial frequency domains - Traditional wavelet packet
Classification code:655.2 Satellites - 716 Telecommunication; Radar, Radio and Television - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 731.1 Control Systems - 801 Chemistry - 821.0 Woodlands and Forestry - 913.3 Quality Assurance and Control - 921 Mathematics - 933 Solid State Physics
DOI:10.3969/j.issn.1002-6819.2015.01.025
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 17>
Accession number:20151000594747
Title:Non-destructive hyperspectral measurement model of chlorophyll content for citrus leaves
Authors:Yue, Xuejun (1); Quan, Dongping (1); Hong, Tiansheng (1); Wang, Jian (1); Qu, Xiangming (1); Gan, Haiming (1)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment (South China Agricultural University), Ministry of Education, Guangzhou, China; (2) Division of Citrus Machinery, China Agriculture Research System, Guangzhou, China; (3) College of Engineering, South China Agricultural University, Guangzhou, China
Corresponding author:Hong, Tiansheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:294-302
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditional methods of obtaining chlorophyll content of citrus leaves require grinding citrus leaves and applying chemical titrations, which would be harmful to citrus trees and time-consuming. Besides, it's difficult to integrate those chemical methods into variable spraying system as a feedback subsystem. In this paper, we discuss several rapid and non-destructive methods in obtaining chlorophyll content of citrus leaves by using hyperspectral analysis system. Hyperspectral technology obtains synchronously spectrum in continuous space, where we can derive crop growth information visually in a non-destructive way. In this paper, the modeling of chlorophyll content of citrus leaves based on the hyperspectrum was discussed. Field experiments were conducted on 117 planted Luogang citrus trees in the Crab Village of Luogang District, Guangzhou City, Guangdong Province. Hyperspectral reflectance and chlorophyll content of citrus leaves were measured by spectrometer (ASD FieldSpec 3) and traditional spectrophotometry, respectively, during four different growth periods corresponding to germination period, stability period, bloom period and harvesting period. In this way, each sample was presented as an instance-labeled pair, where a high-dimensional vector was regarded as the descriptor along with the measured value of chlorophyll content. All the collected samples constituted a large-scale dataset with totally 468 tuples, 80% of which were utilized as the training set and remaining 20% as the testing set. The model constructed relied on the training set and the testing set was evaluated respectively. Using original spectrum and its transformations as input vector, two models, support vector regression (SVR) based on principle component analysis (PCA) and partial least square regression (PLSR) based on the wavelet denoising were adopted, where PCA was adopted for dimension reduction and the wavelet denoising technique removed high-frequency noise. The two models (SVR and PLSR) were then applied to the final regression analysis for predicting chlorophyll content. The best coefficient of determination (R<sup>2</sup>) of the calibration set and a validation set of the entire growth period were up to 0.8713 and 0.8670, the root-mean-square error (RMSE) was 0.1517 and 0.1544 respectively. Some main conclusions were obtained: first, when the original reflectance spectrum was used as the input vector and the energy ratio remained 96% for PCA in germination period and stability period, 99% for PCA in bloom period, harvesting period and the whole growth period, SVR with the radial basis function (RBF) as the kernel function achieved the best performance. Second, the wavelet denoising for hyperspectrum data could improve the model performance to some extent. When "sym8" was used as the wavelet basis function, "rigrsure" as the threshold selection, "sln" for rescaling using a single estimation of level noise based on first-level coefficients as the threshold rescaling project and the decomposition layer was 5, PLSR achieved the best result in this research and the coefficient of determination of calibration set and the validation set of the whole growth period were up to 0.8706 and 0.8531, which increased by 8.3% and 9.3% compared with the model without the wavelet denoising. Third, comparative tests between our best model and other models demonstrate the validity and robustness of the two models we derived. Further experimental results revealed that these two models were superior to principle component regression (PCR), stepwise multiple linear regression (SMLR) and back propagation (BP) neural networks. Finally, hyperspectral technology could obtain accurate chlorophyll content of citrus leaves rapidly, quantitatively and non-destructively, our research may provide a theoretical basis for nutrition surveillance of citrus growth. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Principal component analysis
Controlled terms:Backpropagation - Blooms (metal) - Calibration - Chemical analysis - Chlorophyll - Cultivation - Drug products - Forestry - Functions - Linear regression - Mean square error - Nondestructive examination - Plants (botany) - Radial basis function networks - Reflection - Regression analysis - Spectrum analysis - Statistical tests - Vectors - Wavelet decomposition
Uncontrolled terms:Citrus leaves - Hyper spectra - Partial least square regression - Principle component analysis - Support vector regression (SVR)
Classification code:421 Strength of Building Materials; Mechanical Properties - 461.6 Medicine and Pharmacology - 461.9 Biology - 535.1.2 Rolling Mill Practice - 711 Electromagnetic Waves - 723.4 Artificial Intelligence - 801 Chemistry - 801.2 Biochemistry - 804 Chemical Products Generally - 821.0 Woodlands and Forestry - 821.3 Agricultural Methods - 921 Mathematics - 922.2 Mathematical Statistics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2015.01.039
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 18>
Accession number:20151000594732
Title:Corn ears image selection method for directional seeding
Authors:Wang, Qiao (1); Chen, Bingqi (1); Yang, Xi (1); Liu, Changqing (2)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China; (2) College of Mechanical and Electrical Engineering, Beijing Union University, Beijing, China
Corresponding author:Chen, Bingqi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:170-177
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Corn production occupies an extremely important strategic position in grain production and grain security. Seeds are the most basic means of production in crop production, and the quality of seeds directly affects the subsequent crop cultivation, harvest yield and quality of grain. Moreover, directional seeding of corn can effectively improve the yield of corn, and it is necessary to select seeds before planting. Certainly, to choose good corn ears for threshing can get better corn seeds, which can lighten the workload of subsequent seeds selection and also improve efficiency. So, this study designed the scheme of corn ears selection device based on machine vision, and developed the selection algorithm for corn ears on the dynamic assembly line, which could complete the detection of the corn ears. First, the binary image of the corn ear to be detected was gained according to Otsu method, and after tracking the whole corn ear's contour, the length ratio between the long axis and short axis of the corn ear's contour was calculated. Then, by using the formula, R plus G minus B times 2|, the area with yellow characteristics was strengthened and was even extracted after histogram threshold segmentation, and so the plumpness of the corn ear was detected by calculating the ratio of the extracted area and the whole area of the corn ear. Further, based on the characteristics of X cumulative distribution diagram, the middle ear row was extracted by tracking the seams' edge between ear rows. Also, based on the characteristics of ear row's Y cumulative distribution diagram, every seed in the middle ear row was extracted by using the method of threshold segmentation, and then the length-width ratio of their end-face was calculated by tracking their contour. And the flatness of the seeds was acquired. For the corn ears' video file acquired on the dynamic assembly line, only when the vertical coordinate of corn ear's center is located in image's central region, do the relevant frame image is tested. According to the characteristic parameter, the length ratio between the long axis and short axis of corn ears, the small corn ears were eliminated. The plumpness of corn ears, the corn ears which were mildewed or seriously lacked seeds were eliminated by the characteristic parameter, and, the flatness of corn ears, the corn ears in which the end-face of corn seeds were mostly round were eliminated by those parameters. This corn ears selection algorithm can rapidly and accurately detect the various characteristic parameters of corn ears, and finally determines their eligibility. In the experiment, 50 random samples of corn ears were detected, and the results showed that the determination accuracy of dynamic location was 100%, the recognition accuracy of identical corn ears was 100%, the detection accuracy of morphological characteristics was 100%, the detection accuracy of corn ears' plumpness (on the other hand, the degree of seed lack or mildew) was 96%, the detection accuracy of rectangular degree of seeds' end-face in corn ears is 98%, and the overall detection accuracy was 94%. This paper provides reference for the research on corn ears selection as well as corn seeds selection which is served for directional seeding. This paper provides reference for the research on corn ears selection early in corn seeds selection which is served for directional seeding. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Seed
Controlled terms:Assembly - Assembly machines - Computer vision - Crops - Cultivation - Grain (agricultural product) - Image processing
Uncontrolled terms:Corn ears - Cumulative distribution - Means of productions - Morphological characteristic - Recognition accuracy - Selection - Threshold segmentation - Vertical coordinates
Classification code:601.1 Mechanical Devices - 741 Light, Optics and Optical Devices - 741.2 Vision - 821.3 Agricultural Methods - 821.4 Agricultural Products - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2015.01.024
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 19>
Accession number:20151000594739
Title:Optimization on preparation process parameters of glucose solutions emulsified diesel
Authors:Sun, Jiao (1); Chen, Zhenbin (1); Liu, Jun (2); Liu, Saiwu (1); Wang, Xiaochen (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Hainan University, Haikou, China; (2) College of Automotive Engineering, Tongji University, Shanghai, China
Corresponding author:Chen, Zhenbin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:228-235
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to study the stability and fuel economy of glucose as a substitute for diesel fuel, this paper presented an experimental scheme and experimental procedures for the stability test of glucose solution emulsified diesel based on the design of experiment (DoE). The effects of glucose which instead of alcohol fuels on stability of glucose solution emulsified diesel were developed. Glucose solution emulsified diesel, a kind of potential renewable energy which is clean and environment-friendly, can be used as fuel in diesel engine directly. It not only improves the performance and emissions of diesel engines, but also can be applied to diesel engines without any modification. Glucose solution emulsified diesel is a mixture with glucose and water, which is experienced with stratification, flocculation, coalescence and demulsification process, the stability of the emulsified fuel products is an very important factor for its large scale application. At the same time, the choice of emulsifier, latent solvent and hydrophilic and lipophilic balance (HLB) value are important parameters which can affect the stability of glucose solution emulsified diesel. In this paper, the impacts of emulsifier types, HLB value, dosage of emulsifier, types of latent solvent, dosage of latent solvent, dosage of glucose aqueous solutions and dosage of glucose in solutions on the stability of glucose solution emulsified diesel were studied. According to HLB theory and emulsification principles, compound reagents instead of single reagent were selected as emulsifier on stability of glucose solution emulsified diesel, and the preparation experiments and the scope of the value were determined. Reagents scope were as follows: HLB value 5-6.5, Span80 and Tween80 as compound reagents, castor oil as latent solvent, glucose aqueous solutions 10%-25% and glucose in solutions 10%-25%. A response surface model based on test data was constructed using the software Design-Expert. Resorting to the response surface model, stability time of emulsified fuel was obtained and preparation parameters of glucose solution emulsified diesel were optimized. The optimum processing of glucose solution emulsified diesel was: compound reagents 2.43%, castor oil 1.08%, pure diesel 81.49%, HLB value 5.77, aqueous glucose solutions 15% and glucose in solutions 16.83%. In this condition, it could stay stable without separation in a plug tube at room temperature for 264.2h. In order to improve the accuracy of the characteristic test, parameter of the optimal processing was kept one significant digits after the decimal point as the following: compound emulsifier 2.4%, castor oil 1.1%, pure diesel 81.5%, HLB value 5.8, aqueous glucose solutions 15% and glucose in solutions 16.8%, and it could stay stable without separation in a plug tube at ambient temperature for 252 h, which has 4.62% error component with software simulation value. The experiment was carried out on an automotive diesel engine fuelled by glucose solution emulsified diesel and pure diesel with the method of European stationary cycle (ESC). The result showed that fuel consumption of glucose solution emulsified diesel was 238.14 g/(kW·h) while that of pure diesel was 205.70 g/(kW·h). Based on the optimal processing parameters, the cost of glucose solution emulsified diesel was calculated. the calculation result was as follows: economy characteristics of glucose solution emulsified diesel costs 1.786 yuan and that of pure diesel costs 1.598 yuan. This consistent with our expectation that this study will assist in support of industrial development and application of the glucose solution emulsified diesel. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Diesel engines
Controlled terms:Alcohol fuels - Computer software - Convergence of numerical methods - Costs - Design of experiments - Diesel fuels - Emulsification - Engines - Fuel consumption - Fuel economy - Fuels - Glucose - Oil shale - Software design - Software testing - Solutions - Solvents - Stability - Surface properties - Tubes (components) - Vegetable oils
Uncontrolled terms:Aqueous glucose solutions - Industrial development - Large-scale applications - Parameter optimization - Performance and emissions - Preparation parameters - Preparation process - Response surface modeling
Classification code:512.1 Petroleum Deposits - 521 Fuel Combustion and Flame Research - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 612 Engines - 612.2 Diesel Engines - 616.1 Heat Exchange Equipment and Components - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 801 Chemistry - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 804.1 Organic Compounds - 901.3 Engineering Research - 911 Cost and Value Engineering; Industrial Economics - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity - 951 Materials Science - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2015.01.031
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 20>
Accession number:20151000594719
Title:Fuzzy self-adjusting proportion integration differentiation for eppo quadrocopter
Authors:Liu, Haopeng (1); Long, Changjiang (1); Wan, Peng (1); Wang, Xiaoyi (1); Hu, Ben (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan, China
Corresponding author:Long, Changjiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:71-77
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As quadrocopters can fly stably and be controlled flexibly so that they could fulfill the requirements for seeding, farmland information acquisition and ultra-low-volume spraying. Conventional PID control algorithm could hardly resist the environmental perturbation as structural parameters changed. In this study, a fuzzy proportion, integration and differentiation (PID) control algorithm was proposed to improve the robustness of a plant protection quadrocopter when the load changed during the operation. In the fuzzy PID control algorithm, the errors of the attitude angle and the angular speed were detected and imported into the fuzzy rule table, where correction amount was then calculated and used to correct the initial PID parameters. The updated attitude angle and the angular speed could meet the requirements of the system with a better static and dynamic performance during flight. A quadrocopter control system using STM32 Micro Control Unit (MCU) as the core processor was designed based on the study of the flight theory of aircrafts and the methods of attitude determination. The attitude heading reference system (AHRS) module was adapted as a real-time solver to determine the aircraft attitude parameters so that the flight attitude could be controlled by fuzzy PID algorithm. The matlab-simulink software was used in this study to simulate the conventional PID and fuzzy PID control algorithms and the simulation results were analyzed and compared. For the conventional PID algorithm, the overshoot of the system was 41.9% with the rising time of 0.78 s. With the fuzzy PID control algorithm, the overshoot of the system was 28. 6% and the rising time was 0.69 s. With fuzzy PID control algorithm, the overshoot of the system decreased 13.3% and the rising time reduced 0.09 s compared with the conventional PID algorithm with the scaling factor as 5, integral coefficient as 0.03, differential coefficient as one and system gain as one. Using other parameters have also led to similar results, which indicated that fuzzy PID control algorithm had a better control performance. Moreover, experiments were conducted to verify the simulation results. The results showed that, the system performed in a stable way under a small load with the control of the fuzzy PID algorithm; however, this cannot be achieved by using the conventional PID algorithm under same condition. With the conventional PID algorithm, the overshoot of the system was 37.5% and the rising time was 0.62 s with a heavy load. While, the overshoot of the system was 22.5% and the rising time was 0.57s when the fuzzy PID control algorithm was adopted. The overshoot of the system decreased 15.0% and the rising time reduced 0.05 s, which agreed well with the simulation results. The results showed that the fuzzy PID algorithm had a stronger adaptability with easier adjustment of working parameters and can lead to quicker dynamic response capability and more stability of the system when compared with the conventional PID algorithm. The performance and disturbance rejection ability of the plant protection quadrocopter were significantly improved by using the proposed fuzzy PID algorithm. This study can provide a reference for the research of plant protection aircraft control algorithm. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Algorithms
Controlled terms:Aircraft - Aircraft control - Computer software - Discrete time control systems - Disturbance rejection - Dynamic response - Flight control systems - MATLAB - Parameter estimation - Proportional control systems - Seed - Sensors - System stability - Three term control systems
Uncontrolled terms:Differential coefficient - Environmental perturbations - Flight control - Fuzzy self-adjusting - Information acquisitions - Matlab-Simulink software - Proportion integration differentiations - Static and dynamic performance
Classification code:408.1 Structural Design, General - 652 Aircraft and Avionics - 652.1 Aircraft, General - 723 Computer Software, Data Handling and Applications - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 732 Control Devices - 801 Chemistry - 821.4 Agricultural Products - 921 Mathematics - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2015.01.011
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 21>
Accession number:20151000594731
Title:Drought risk assessment in complex landform area
Authors:Lu, Xiaoning (1); Hong, Jia (1); Wang, Lingling (1); Zhang, Jingyi (1)
Author affiliation:(1) Chengdu University of Information Technology, Chengdu, China; (2) Open Research Fund Program of Plateau Atmosphere and Environment Key Laboratory of Sichuan Province, Chengdu, China; (3) Key Laboratory of Geo-special Information Technology, Ministry of Land and Resources, Chengdu University of Technology, Chengdu, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:162-169
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This article intended to achieve drought risk assessment in complex topography area, such as Sichuan Province, in the support of natural disaster risk theory and multi-source data, especially satellite data which was widely used to reflect the properties of study area from different angles including meteorology, hydrology, topography. In detail, TRMM satellite precipitation data was used to make up for the shortage of data from meteorological stations. And the latitude, longitude and digital elevation model were introduced to improve the accuracy of temperature interpolation; furthermore, drought frequency instead of drought degree was calculated using Normalized Vegetation Index data to more accurately quantify drought risks. Meanwhile, an index of water acquisition cost was constructed to quantify the affections of terrain on water distribution and acquisition. In addition, raster data were used as far as possible, such as raster populations and economies. Thus, an index system which revealed variable properties of study area in different angles was constructed. And then, weights of the index system were calculated using entropy method. Finally, the drought risk in Sichuan Province was assessed. The accuracy of this assessment was tested by agricultural drought risk loss. It showed a high correlation between the agricultural loss and the drought risk achieved from this paper (R<sup>2</sup>=0.8347, P<0.001). Thus, the reliability of this research in aspect of drought risk assessment in complex topography areas was proved. Through the analysis of drought risk assessment result, it showed that: 1) Most of Sichuan Basin, part of Panzhihua and Liangshan showed high drought risks; 2) Northern Guangyuan, Bazhong, Dazhou, most of Liangshan and Panzhihua, southern Yibin and Luzhou reached average risk degrees, as well as some valleys in the Western Sichuan Plateau; 3) However, there was quite low risk in most of the Western Sichuan Plateau. Through this study, it proved that the index system and method in drought risk assessment had some reference significance especially in complex topography areas. At the same time, there were some shortages which needed to be improved. 1) Using Entropy method, statistical characteristics of data was fully taken into consideration, and weights of the indexes were determined according to the variation of each index. However, it failed to distinguish the importance of each index. To improve the accuracy of weight determination in further study, it was best to combine the objective method and subjective method. 2) The spatial resolution was greatly improved by introducing a large number of spatial data into study, which was a great breakthrough in drought risk assessment, for most studies just took administrative region as the basic unit. However, uncertainty was actually inevitably increased because of the accuracy problem of spatial data itself. 3) According to the requirements of natural disaster risk theory, 4 factors and 11 indexes were selected to construct the assessment system, which basically met the need of drought risk assessment in the study area. But the assessment system may need a further refinement and improvement in order to be able to reflect the complex background information of the complex topography area in all aspects more accurately and comprehensively. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Risk assessment
Controlled terms:Agriculture - Disasters - Drought - Geomorphology - Landforms - Meteorology - Population statistics - Topography - Water supply systems
Uncontrolled terms:Agricultural drought - Complex topographies - Digital elevation model - Meteorological station - Natural disaster risk - Statistical characteristics - Temperature interpolations - Weight determination
Classification code:443 Meteorology - 444 Water Resources - 446.1 Water Supply Systems - 481.1 Geology - 481.1.1 Geomorphology - 484 Seismology - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.1 Probability Theory - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2015.01.023
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 22>
Accession number:20151000594742
Title:Carbon emission and its influence factors of subalpine forest soil in Southwest China
Authors:Li, Weipeng (1); Sun, Jian (4); Sha, Yukun (1); Cheng, Genwei (1)
Author affiliation:(1) Key Laboratory of Mountain Environment Evolution and Regulation, Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu, China; (2) School of Land and Resources, China West and Normal University, Nanchong, China; (3) College of Resources and Environment, University of Chinese Academy of Sciences, Beijing, China; (4) Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:255-263
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Numerous results of carbon (C) emission of the subalpine dark conifer forest showed more or less differences for the great and complicated environmental temporal-spatial variation in the Gongga Mountain region in Southwestern China. For a more exact estimation of soil C emission in the subalpine forest and a more clear understanding of its impacting factors in the Mount Gongga, with the Li-6400-09 chamber, the soil CO<inf>2</inf> emission and the main environment factors of the Abies fabri forests were studied. The results showed soil C storage (291.0 t/hm<sup>2</sup>, 49.8% of the forest ecosystem) in the mature Abies fabri forest is higher than that (63.8 t/hm<sup>2</sup>, 30.7% of the forest ecosystem) in middle-aged Abies fabri forest, which indicated the effects of stand age on soil C storage. Overall, the annual variation of the soil C emission rate in the mature Abies fabri forest showed a similar tendency as that in the middle-aged Abies fabri forest. For both of the mature and middle-aged Abies fabric forests, the monthly soil C emission rate in the growing season (May to October) is much higher than that in the non-growing season (November to the next April), and the maximum in summer is 5~6 times as large as that of the minimum in winter; while the soil C emission rate each month in the mature Abies fabri forest is on average 1.5 times as large as that in the middle-aged Abies fabri forest. The soil temperature, soil moisture and monthly soil CO<inf>2</inf> emission rate generally fluctuate in synchrony under the warm and humid climate during growing season. The peak of monthly soil CO<inf>2</inf> emission rate in the middle-aged Abies fabri forest, 34.53 kg C/(hm<sup>2</sup>·d), occures in July (the warmest and the most humid month for both of the forest soils in middle-aged and mature Abies fabri forest), while the valley, 6.96 kg C/(hm<sup>2</sup>·d), appears in February (the coldest and driest month for the forest soils in middle-aged Abies fabri), with an average of 16.26 kg C/(hm<sup>2</sup>·d) and a variation coefficient of 0.54.The maximum of monthly soil CO<inf>2</inf> emission rate in the mature Abies fabri forest, 55.34 kg C/(hm<sup>2</sup>·d), delays one month to August, and there are two small peaks in May and December, respectively; while the minimum, 9.50 kg C/(hm<sup>2</sup>·d), delays to January, later than December that is the driest month for the mature Abies fabri forest soil, and earlier than March, the coldest month. The soil C emission rate in the mature Abies fabri forest has an average of 24.57 kg C/(hm<sup>2</sup>·d) and a variation coefficient of 0.61, which implies the mature Abies fabri forest ecosystem has more self-adjusting function. The daily average soil CO<inf>2</inf> emission rate has more obvious correlation with soil temperature in 5 cm depth (the representative layer for the microbial activity and upper soil average heat condition) rather than air temperature, relative humidity, precipitation, and photosynthetically active radiation (PAR) in both the mature and middle-aged Abies fabri forests (r=0.73, P<0.05; the two forests are the same), and the fitted curves showed their exponential relationships (R<sup>2</sup>=0.60 for the mature forest and R<sup>2</sup>=0.56 for the middle-aged forest). In the subalpine cold-humid condition, without the high temperature inhibition, the soil moisture (monthly variation ranged from 14% to 30%) can hardly become the limiting factor, while the soil temperature plays a key role on soil C emission. Under the typical Intergovernmental Panel on Climate Change (IPCC) series of emission scenarios (SRES), i.e., B1, A1B and A2, the soil C emissions are expected to be increased by 15%, 25% and 31% respectively from the mature Abies fabri forest soil, and by 13%, 21% and 17% respectively from the middle-aged Abies fabri forest soil. It indicates that the stand age should be attached more importance in the C emission investigation and monitoring. The research provides basic data and references for the C balance estimation in the region under changing environment. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Soils
Controlled terms:Carbon - Carbon dioxide - Climate change - Digital storage - Ecology - Ecosystems - Forestry - Moisture - Soil moisture - Temperature
Uncontrolled terms:Climate scenarios - Emission rates - Intergovernmental panel on climate changes - Photosynthetically active radiation - Self adjusting function - Sub-alpine - Variation coefficient - Warm and humid climates
Classification code:451 Air Pollution - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 641.1 Thermodynamics - 722.1 Data Storage, Equipment and Techniques - 801.4 Physical Chemistry - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821.0 Woodlands and Forestry
DOI:10.3969/j.issn.1002-6819.2015.01.034
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 23>
Accession number:20151000594716
Title:Microstructure and property of 65Mn steel preheated by laser strengthening
Authors:Huang, Yongjun (1); Zhang, Guozhong (1)
Author affiliation:(1) Engineering College, Huazhong Agricultural University, Wuhan, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:53-57
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, there exists a problem that the agricultural tools easily get worn. However, the common strengthening techniques have visible disadvantages, such as the complex process and comparatively high running cost. In order to solve the problem, the 65Mn steel was preheat-treated by the normalization or quenching+medium-temperature tempering. Subsequently, the preheat-treated 65Mn steel was strengthened by laser quenching or laser melting-hardening process with a YLR-6000 fiber laser. The microstructure was studied by optical microscope and scanning electronic microscope. The microhardness was measured using a Vickers-1000 microhardness tester with load of 1.96N and a dwelling time of 15s. Further, the controlling factors were investigated. The results showed that the preheat-treating and laser process had visible influences on the microstructure and property. In laser quenching, the microstructure was comprised of the entire quenching zone, part quenching zone and heat affected zone. The fine needle martensite was obtained in entire quenching zone by quenching+medium-temperature tempering+laser quenching. In the part quenching zone, the microstructures were fine needle martensite and troolstite. However, the fine needle martensite and a few ferrite were observed in entire quenching zone by normalization+laser quenching. In the laser melting-hardening process, the microstructure was made up of the surface melting zone, entire quenching zone, part quenching zone and heat affected zone. Compared with the microstructure of laser quenching, the surface melting zone was obtained in laser melting process, and the others were accorded with those in laser quenching. As for laser melting process, the depth of surface melting zone was within the range of 10-15 µm. In surface melting zone, the fine dendrite microstructure was got and the primary dendrite arm spacing was within the range of 4~6 µm. In addition, The microhardness of laser strengthening 65 Mn steel pretreated by normalization was relatively higher than that pretreated by quenching + medium-temperature tempering. It depended on the microstructure and its size. Moreover, the microhardness of laser melting-hardening was relatively lower than that of laser quenching. The microhardness of laser process could reach up to HV0.2830, about 1.5 times as much as that of common quenching + medium-temperature tempering. According to the working condition of agricultural tools, the surfaces needed to be hard and the interior parts needed to be with good toughness. The laser strengthening technique satisfied the request of steel property and simplified the running process. Therefore, in terms of agricultural tool strengthening approaches, the laser strengthening technique exhibits visible advantages and brings application prospects. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:12
Main heading:Quenching
Controlled terms:Agricultural implements - Agricultural machinery - Agriculture - Fiber lasers - Hardening - Heat affected zone - Laser beam welding - Manganese - Martensite - Melting - Metal melting - Microhardness - Microstructure - Needles - Steel fibers - Strengthening (metal) - Tempering
Uncontrolled terms:Dendrite microstructure - Laser melting - Laser quenching - Microstructure and properties - Primary dendrite arm spacings - Property - Scanning electronic microscopes - Strengthening technique
Classification code:421 Strength of Building Materials; Mechanical Properties - 531.1 Metallurgy - 537.1 Heat Treatment Processes - 538.2 Welding - 538.2.1 Welding Processes - 543.2 Manganese and Alloys - 545.3 Steel - 741.1.2 Fiber Optics - 819.4 Fiber Products - 819.6 Textile Mills, Machinery and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 933 Solid State Physics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.008
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 24>
Accession number:20151000594723
Title:Modeling resistance of soil evaporation and soil evaporation under straw mulching
Authors:Li, Yan (1); Liu, Haijun (2); Huang, Guanhua (1)
Author affiliation:(1) College of Water Resources and Civil Engineering, China Agricultural University, Beijing, China; (2) College of Water Sciences, Beijing Normal University, Beijing, China
Corresponding author:Huang, Guanhua
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:98-106
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Evapotranspiration is the main way of soil water depletion in field, and soil evaporation is an important part of evapotranspiration, and it may account for 32%-50% of the total evapotranspiration during the whole crop growth period. Soil evaporation does little effect on the formation of crop biomass and yield, so reducing soil evaporation is important for improving water use efficiency and agricultural water saving management. In recent years, straw mulching has been used widely due to its capability of improving soil structure, increasing soil organic matter, reducing soil evaporation and maintaining soil water content. Mulching affects exchange of energy and heat between soil surface and free air, so the mechanism for soil evaporation under mulching condition may be different from that without mulching. Considering the fast development of straw mulching, therefore modeling soil evaporation under straw mulching is of important for making agricultural water management. In this paper, the factors (soil water content and mulching amount) that affect soil evaporation had been analyzed, the values of mulching resistance were calculated, the equations for calculating resistance of mulching and the resistances of soil evaporation and soil evaporation under straw mulching had been established, the parameters for the equation had been determined. The experiment was carried out from late July to middle August in 2010 and from middle July to middle August in 2011, respectively. The undisturbed soil with winter wheat plants was prepared and put into plastic buckets when winter wheat was maturity, two main treatments (stubble and stubble+mulch treatments) were set up, there were five sub-treatments for each of the two main treatments. The stubble heights for stubble treatments were 0, 5, 15, 25, 35 cm. Stubble heights were 0, 5, 15, 25, 35 cm with mulching amounts of 0.47, 0.43, 0.348, 0.267, 0.187 kg/m<sup>2</sup> in stubble+mulch treatment, respectively. The total biomass (stubble biomass) for each stubble treatment was 0, 0.04, 0.122, 0.203, 0.283 kg/m<sup>2</sup>, respectively; the total biomass (stubble biomass and mulching amount) in each stubble+mulch treatment was 0.47 kg/m<sup>2</sup>. During the prepared period, water was applied to the soil until all the soil in the plastic bucket was saturated, and then the excessive water was discharged out off plastic bucket through small hole at the bottom of plastic bucket to make sure soil water content was about field capacity at the beginning of the experiment. The soil evaporation and soil temperature were measured daily and soil water content in 0-2 cm depth was measured every 2~5 days according to the soil evaporation. Meteorological data, including relative humidity, hourly mean air temperature, and wind speed were measured with an automatic weather station. Results showed that the relative soil evaporation (the ratio of soil evaporation to water evaporation from 20 cm diameter pan) kept relatively stable when soil water content was higher than 0.23 cm<sup>3</sup>/cm<sup>3</sup> (60% field capacity), the ratio declined linear with the decreasing of soil water content when soil water content was higher than 0.05 cm<sup>3</sup>/cm<sup>3</sup> (wilting point) and less than 0.23 cm<sup>3</sup>/cm<sup>3</sup>. Mulching affected soil evaporation, reducing stubble height and increasing mulching amount could reduce soil evaporation when the total biomass was the same. The total amount of soil evaporation during experiment period reduced by 8%-51% under stubble+mulch treatment with mulching amount of 0.348-0.47 kg/m<sup>2</sup> compared with stubble treatment when stubble height was 0-15 cm. Mulching resistance was 158-600 s/m in this study and it was exponentially increasing with the mulching amount, and the resistance of soil layer decreased linearly with the soil water content increasing when soil water was less than 0.23 cm<sup>3</sup>/cm<sup>3</sup> and higher than 0.05 cm<sup>3</sup>/cm<sup>3</sup>. The validation processes showed that the developed method and related parameters (mulching resistance and the resistance of soil layer) performed well for modeling soil evaporation under mulching condition. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:47
Main heading:Soils
Controlled terms:Agriculture - Atmospheric temperature - Biomass - Crops - Evaporation - Evapotranspiration - Meteorology - Moisture - Soil moisture - Water conservation - Water management - Water supply - Weather information services - Wind
Uncontrolled terms:Agricultural water management - Automatic weather stations - Mean air temperatures - Meteorological data - Soil organic matters - Stubble mode - Stubble with mulching mode - Water use efficiency
Classification code:443 Meteorology - 443.1 Atmospheric Properties - 444 Water Resources - 446 Waterworks - 446.1 Water Supply Systems - 483.1 Soils and Soil Mechanics - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2015.01.015
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 25>
Accession number:20151000594728
Title:Migration rule of non-point source pollutions from seasonal frozen soil in small watershed scale during thawing period
Authors:Zhao, Qiang (1); Wang, Kang (1); Huang, Jiesheng (1); Dong, Jianwei (2)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan, China; (2) Jilin Institute of Water Resources Research, Changchun, China
Corresponding author:Wang, Kang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:139-145
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Field experiments were conducted to monitor hydrology and pollutant exudation from frozen soil to river during the thawing period in the Hedingzi watershed located in Shuangyang district, Changchun, China. The sub-watersheds in the Heidingzi watershed were divided into four typical drainage areas. The exudation processes of water and pollutants in the watershed scale were determined using mass balance method. In the drainage area of Type I, the water and pollutants exudation processes were dominated by the flow paths from paddy field to the outlet of the main drains. In the drainage areas of Type II and III where maize was planted, the variation of exudation of water and pollutants became more significant as more land use information was included. Water and pollutant exudation amount per unit area in the rural point sources (drainage area of Type IV) was higher than that in paddy and maize fields significantly. Water and pollutant exudation processes were greatly affected by the initial condition, area, slope of the drainage area. In the drainage areas of Types I, II and III, the NH<inf>4</inf><sup>+</sup> exudation was mainly from the region above the unthawed layer, and significant changes of water content and NO<inf>3</inf><sup>-</sup> concentration were observed in the region from soil surface to the maximum freezing depth during the thawing process. However, during the freezing process, water and pollutants showed significantly different redistribution processes for the underlying surface of paddy and maize fields; in paddy area, the average soil water content increased from 0.325 to 0.487 cm<sup>3</sup>/cm<sup>3</sup>, the NH<inf>4</inf><sup>+</sup> mass from 0.120 to 0.174 g/m<sup>2</sup>, the NO<inf>3</inf><sup>-</sup> mass from 0.628 to 0.918 g/m<sup>2</sup>; in maize area, the average soil water content increased from 0.264 to 0.301 cm<sup>3</sup>/cm<sup>3</sup>, NH<inf>4</inf><sup>+</sup> and NO<inf>3</inf><sup>-</sup> mass still showed significant changes, i.e., the NH<inf>4</inf><sup>+</sup> mass increased from 0.08 to 0.14 g/m<sup>2</sup> while the NO<inf>3</inf><sup>-</sup> mass from 0.636 to 0.766 g/m<sup>2</sup>. The pollutant fluxes were estimated by the mass difference between input and output of watershed scale and accumulated exudation fluxes of sub-watershed scale, respectively. The differences of NH<inf>4</inf><sup>+</sup> and NO<inf>3</inf><sup>-</sup> fluxes between the two estimation methods were 20.99% and 0.66%, respectively. The two estimation methods for water and pollutant fluxes were consistent. During the thawing process, the average degradation rates of NH<inf>4</inf><sup>+</sup> and NO<inf>3</inf><sup>-</sup> were 0.12 and 0.01 d<sup>-1</sup>, and NH<inf>4</inf><sup>+</sup> flux showed significant variation in the main stream. During the thawing process, the variation coefficient of NH<inf>4</inf><sup>+</sup> flux was significant lower than that of NO<inf>3</inf><sup>-</sup> flux. The thawing was downward from the surface and upward from the maximum freezing depth; the exudation amounts of water, NH<inf>4</inf><sup>+</sup> and NO<inf>3</inf><sup>-</sup> per unit area accounted for 32.9%-74.6%, 96.3%-243% and 28.6%-182% of the changes of soil water content, NH<inf>4</inf><sup>+</sup> mass and NO<inf>3</inf><sup>-</sup> mass above the unthawed layer, respectively; and 10.6%-59.2%, 26.4%-110%, 17.6%-76.4% at the maximum freezing depth, respectively. The ratio of soil water flux between horizontal and vertical directions decreased from 1.45 to 0.119.The study can provide the reference for understanding the rule of water and pollutant exudation from frozen soil during the thawing period. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Soil pollution
Controlled terms:Degradation - Freezing - Frozen soils - Hydrology - Land use - Pollution - River pollution - Soil moisture - Soils - Thawing - Water pollution - Water treatment - Watersheds
Uncontrolled terms:Initial conditions - Mass-balance method - Non-point source pollution - Redistribution process - Small watersheds - Soil water content - Thawing period - Variation coefficient
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 444.1 Surface Water - 445.1 Water Treatment Techniques - 453 Water Pollution - 454.2 Environmental Impact and Protection - 471 Marine Science and Oceanography - 483.1 Soils and Soil Mechanics - 802.2 Chemical Reactions - 802.3 Chemical Operations - 822.2 Food Processing Operations
DOI:10.3969/j.issn.1002-6819.2015.01.020
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 26>
Accession number:20151000594722
Title:Characteristics of flow field near membrane surface based on particle image velocimetry technology
Authors:Guo, Xiao (1); Li, Chunli (1); Qiu, Guangming (1); Tian, Rui (1)
Author affiliation:(1) College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot, China; (2) Inner Mongolia Renewable Energy Key Laboratories, Hohhot, China
Corresponding author:Tian, Rui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:91-97
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This study built the test system of membrane surface flow field. The system was built under the condition of photo-metric optical fiber instead of hollow fiber membrane filaments. The paper analyzed the affection regularity of aeration intensity to fluid mechanics characteristics of hollow fiber membrane surface under the condition of clear water and three different aeration pore sizes of 1, 1.5, 2.5 mm based on the particle image velocimetry (PIV) technology. Further experiments were carried out on the variation of turbulence intensity values of hollow fiber membrane surface and liquid velocity values under the condition of different aeration intensities for three different aeration pore sizes. The movement of continuous phase (liquid) in PIV technology was marked by fluorescent particles to identify the velocity field of liquid. Under the conditions of this experiment, the trajectory of the bubble itself could reflect its velocity vector substantially, and the velocity field of each phase can be obtained after the phases were separated when we used the image processing techniques of each single phase. The results indicated that the increasing range of the average liquid velocity on the surface of the membrane appeared to be the highest when the aeration intensity was 140 L/h; and when over 140 L/h, it decreased to be much lower, so under the condition of this experiment, the optimum aeration intensity is 140 L/h, and more optimal turbulence intensity values are corresponding to this aeration intensity. In the project, according to optimized parameters, we can not only save the cost of system operating, but also eliminate the cake layer on the membrane surface and reduce the concentration polarization on both sides of the membrane surface. Under the condition of three different aeration pore sizes, the average speed of the liquid near the membrane surface is basically consistent with the aeration intensity; when the aeration is at 1 mm aperture, the velocity vectors of liquid near the surface of the membrane increase with the increase of aeration intensity, when the aeration intensity is over 140 L/h, the liquid velocity vectors near the membrane surface are basically the same; at lower aeration intensity, the liquid velocity of the membrane surface near the aeration pore is significantly higher than the ones which locate other places, and the liquid appears the phenomenon of rocking after affected by the bubble rising trajectory; at higher aeration intensity, liquid velocity value increases significantly in the horizontal direction; with the increase of the liquid velocity, the ranges of membrane filaments influenced correspondingly increase; and when the aeration intensity reaches 140 L/h, 6 membrane filaments are influenced at different degrees, and the shaking of the bubbles causes the rocking of the membrane filaments, which can play an active role in controlling the pollution of the membrane. This research provides a theoretic foundation for the optimization of flow field in membrane bioreactor so as to improve the membrane fouling problem. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Liquids
Controlled terms:Biological water treatment - Bioreactors - Fibers - Flow fields - Flow visualization - Fluid mechanics - Image processing - Membrane fouling - Membranes - Optical data processing - Optical fibers - Pore size - Testing - Turbulence - Velocimeters - Velocity - Velocity measurement
Uncontrolled terms:Characteristics of flow fields - Concentration polarization - Hollow fiber membranes - Image processing technique - Mechanics characteristics - Particle image velocimetries - Particle image velocimetry technologies - Turbulence intensity
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 445.1 Water Treatment Techniques - 631.1 Fluid Flow, General - 741 Light, Optics and Optical Devices - 802.1 Chemical Plants and Equipment - 812 Ceramics, Refractories and Glass - 817 Plastics and Other Polymers: Products and Applications - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 943.3 Special Purpose Instruments - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.014
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 27>
Accession number:20151000594745
Title:Comparison and analysis of temperature field reappearance in stored grain of different warehouses
Authors:Yin, Jun (1); Wu, Zidan (2); Zhang, Zhongjie (2); Wu, Xiaoming (2); Wu, Wenfu (1)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun, China; (2) Academy of State Administration of Grain, Beijing, China
Corresponding author:Wu, Zidan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:281-287
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Grain storage has very important effects on national security and has been given increasing attentions at past several decades. Condensation is one of the main dangers to the grain storage safety. Temperature, moisture and warehouse type are the three most important factors to form condensation. However, it is very difficult to study the effects of temperature and moisture on the grain storage safety in the actual granary due to the huge cost. So, it is a good choice by building models to forecast the changes of temperature or humidity in the granary by experiments. At present, the studies were still at the middle-small experimental stages in the domestic and overseas. Due to the differences of climate, long storage period and warehouse types at different regions, it is more difficult to build the universal temperature or humidity models in China than other nations. To explore the condensation processes, wheat were storage in steel squat silo and horizontal bin located in Tianjin District respectively, which were used widely to store grain in China. The changes of temperature and water vapor pressure of the wheat in spring, summer and winter were researched in the paper. The grain temperature data in different seasons was obtained by sensors array. Second Newton interpolation method was used to obtain the fitting algorithm of temperature. The data of wheat water vapor pressure was figured out by WU model. The temperature fields and the water vapor pressure field of the wheat in two researched storehouse were reproduced by MATLAB software, respectively. Then, the cloud maps were analyzed according to the coupling principle of temperature and water vapor pressure fields and WU model. The results showed that a large cold area existed in the wheat in the steel squat silo or the horizontal bin in summer, which could be the main reason of non-dewfall and resulted in a storage safety. A multi-level water vapor pressure zone, which was defined as the low-water vapor pressure area and high-ones alternately appeared in the stored wheat, all was observed in the wheat in the steel squat silo and the horizontal bin during late winter to early spring. More significant multi-level water vapor pressure zone (which suggested a larger gradient of grain temperature and water vapor pressure) and more moisture absorbed rate of the surface grain than that of the horizontal bin resulted in the condensation on the surface occurred more easily in the steel squat silo in early spring, which suggested a storage risk of the wheat in spring. The isotherm was different remarkably between the two warehouses. In the steel squat silo, the isotherm was closed, but it presented non-closed in the horizontal bin. Based on the change direction of isothermal curve, it could deduce that there was another horizontal bin bordered. Additionally, the isotherms of the two horizontal bins could close well from the temperature field cloud maps, which suggested grain stored in the bordered horizontal bin. The results were in consistent with the actual. They provided not only new thought of forecasting condensation, but also new perspective of making inventories of warehouses. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Temperature
Controlled terms:Bins - Climate models - Condensation - Digital storage - Grain (agricultural product) - Grain elevators - Hydrostatic pressure - Isotherms - MATLAB - Models - Moisture - National security - Safety engineering - Sensor arrays - Vapor pressure - Warehouses - Water vapor
Uncontrolled terms:Comparison and analysis - Condensation process - Effects of temperature - Fitting algorithms - Grain storage - Grain temperature - Micro-airflow - Newton interpolation
Classification code:443 Meteorology - 443.1 Atmospheric Properties - 631.1.1 Liquid Dynamics - 641 Heat and Mass Transfer; Thermodynamics - 641.1 Thermodynamics - 694.4 Storage - 716 Telecommunication; Radar, Radio and Television - 722.1 Data Storage, Equipment and Techniques - 732 Control Devices - 802.3 Chemical Operations - 821.4 Agricultural Products - 902.1 Engineering Graphics - 902.3 Legal Aspects - 914 Safety Engineering - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2015.01.037
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 28>
Accession number:20151000594720
Title:Establish oriented operating terminals wheel loader duty cycle
Authors:Zou, Naiwei (1); Huang, Hongdao (3); Zhang, Erping (2); Dai, Qunliang (2)
Author affiliation:(1) Jiamusi University, Jiamusi, China; (2) Guangxi Liugong Machinery Co., Ltd., Liuzhou, China; (3) University of Cincinnati, Cincinnati, United States
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:78-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The wheel loader simulation analysis needs oriented operating terminals duty cycle to set the virtual reality environment, and the energy-saving potential research of hybrid or other new type wheel loader should also be based on the duty cycle. But there is no wheel loader duty cycle to date, which obstructs the energy-saving mechanism and simulation research about wheel loader. An oriented operating terminals duty cycle was established based on wheel loader working test data, and the duty cycle described the basic energy consumption rules of wheel loader operating terminals. A CLG862III wheel loader was used for the working test, with the rate load of 6 ton. The testing data was collected at all the operating terminals, the wheel loader worked with two typical materials in the working test, one material was soft earth and the other was raw earth. In order to avoid the difference caused by operators, two operators were engaged in operating the wheel loader, and every test was required to work more than 60 cycles continuously. Ninety percent of the test data was used for relevant features extracting and duty cycle establishment. Statistical analysis was used to extract relevant features from working testing data, the relevant features included 4 series vehicle velocity series, running resistance series, machine weight series and hydraulic resistance torque series. The relevant features were expressed on 4 separate coordinates at the same time sequence to establish wheel loader duty cycle. The duty cycle was established according to the following process: 1) the time sequence was divided into 5 phases on the vehicle velocity coordinate, including: run to pile, input pile, loading backward, run to truck and unload return phase; 2) the 4 transport phases were expressed as vehicle velocity polyline trapeziums by the relevant features, including: the highest velocity, the second highest velocity, maximum acceleration, maximum deceleration and phase continuance time phase continuance time; 3) the input pile phase was combined with running into pile phase as one unit; 4) a smooth vehicle velocity curve was generated by the means of 4 order fitting; 5) the vehicle velocity curve was amended with the constraint condition of wheel loader operated in fix location, that means wheel loader forward driving distance equaled to backward driving distance when it was working; 6) the input resistance relevant features were expressed on the running resistance coordinate, and its time sequence was corresponding with input pile phase; 7) the loading relevant features were expressed on the machine weight coordinate, with load phase started at the beginning of input pile phase and ended at the beginning of unload return phase; 8) 3 steering phases were expressed on the hydraulic resistance torque coordinate, the steering phases were located in the middle of run to pile, loading backward and unload return phase respectively; 9) tilt bucket phase relevant features were expressed on the hydraulic resistance torque coordinate, it was 0.5 s behind input pile phase beginning; 10) lift & steering phase relevant features were expressed on the hydraulic resistance torque coordinate, and it started at the beginning of run to truck phase. The remaining ten percent test data was used to validate the duty cycle. The results showed that duty cycle could accurately describe wheel loader operating terminals power requirement. The wheel loader duty cycle could provide power requirement data for the parameter matching of hybrid driving wheel loader and new types of wheel loader power-train. It could also be used for computer simulation including dynamic analysis. At the same time, it could offer a detailed and unified experimental standard for traditional wheel loader performance testing. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Piles
Controlled terms:Airships - Automobile steering equipment - Construction equipment - Curve fitting - Energy conservation - Energy utilization - Hydraulic machinery - Hydraulics - Loaders - Loading - Materials testing - Mining machinery - Rolling resistance - Steering - Stream flow - Testing - Torque - Truck transportation - Trucks - Vehicles - Velocity - Velocity control - Virtual reality - Wheels
Uncontrolled terms:Constraint conditions - Duty-cycle - Energy consuming rule - Energy saving mechanism - Energy saving potential - Hydraulic resistances - Relevant features - Virtual-reality environment
Classification code:405.1 Construction Equipment - 408.2 Structural Members and Shapes - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 422.2 Strength of Building Materials : Test Methods - 423 Non Mechanical Properties and Tests of Building Materials - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 432 Highway Transportation - 432.3 Cargo Highway Transportation - 502.2 Mine and Quarry Equipment - 525.2 Energy Conservation - 525.3 Energy Utilization - 601.2 Machine Components - 631.1 Fluid Flow, General - 632.1 Hydraulics - 632.2 Hydraulic Equipment and Machinery - 652.5 Balloons and Gliders - 663.1 Heavy Duty Motor Vehicles - 663.2 Heavy Duty Motor Vehicle Components - 723 Computer Software, Data Handling and Applications - 731.3 Specific Variables Control - 818.5 Rubber Products - 921.6 Numerical Methods - 931.1 Mechanics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.012
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 29>
Accession number:20151000594730
Title:Spatio-temporal variability and trend of potential evapotranspiration in Xinjiang from 1961 to 2013
Authors:Dong, Yu (1); Haimiti, Yimiti (1)
Author affiliation:(1) Key Laboratory of Oasis Ecology of Ministry of Education, Xinjiang University, Urumqi, China; (2) College of Resources and Environment Science, Xinjiang University, Urumqi, China; (3) Key Laboratory of Lake Environment and resources in Arid Zone, Xinjiang Normal University, Urumqi, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:153-161
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Evapotranspiration is one of the important parameters in hydrological and meteorological studies. Under the background of global warming, it is essential to accurately estimate the potential evapotranspiration in arid and semiarid areas where the water resources are limited and excessively explored, which would be greatly helpful for planning the irrigation water supply and understanding the effects of climate change on hydrological processes. In this study, observed daily meteorological data during 1961-2013 from 55 meteorological stations, including temperature, relative humidity, wind speed and sunshine hours, are used to calculate the potential evapotranspiration based on Penmen-Monteith equation, the methods of Mann-Kendall test, Cramer's test, correlation analysis and the contributions analysis, for analyzing the spatial distribution and temporal changes in the potential evapotranspiration in XinJiang during 1961-2013. Major results were as follows: from the 1960s to the 1970s, potential evapotranspiration was dominated by positive anomaly, then changed into negative anomaly from 1980s to 1990s, and the annual and seasonal potential evaporation anomaly reached a low point in the 1990's. Potential evapotranspiration anomaly descent in spring and summer is the key contributors to the annual potential evapotranspiration anomaly descent. There was a change point for ET<inf>0</inf> series around the year 1994 based on the Cramer's test. For the average in the region, ET<inf>0</inf> decreased from 1961 to 1994 by 3.21 mm/a, while ET<inf>0</inf> began to increase since 1995 at a rate of 3.51 mm/a. Spatial distribution of ET<inf>0</inf> showed that during 1961-1994, annual ET<inf>0</inf> in most sites (about 75%) had decreasing trends; on the contrary, during 1994-2010, about 76% sites had increasing trends. Based on the latitude, altitude and terrain, the study area was further divided into five climatic regions: the Altay Mountains, the south slope of Tianshan Mountains, the north slope of Tianshan Mountains, the Tianshan Mountain and the north foot of Kunlun Shan. The Cramer's test for detecting a change point in annual ET<inf>0</inf> of five climatic regions found that a change point for ET<inf>0</inf> series was identified around the year 1994. Annual ET<inf>0</inf> of five climatic regions decreased from 1961 to 1994 and increased significantly from 1995 to 2013. The results indicated that wind speed, sunshine duration and relative humidity showed reverse trends during the period of 1995-2013 compared to the period of 1961-1994, and the temperature increasing was more significant since 1994. During 1961-1994 and 1995-2013, among all tested meteorological factors, wind speed had the highest complete correlation coefficient with ET<inf>0</inf> in XinJiang. There does exist difference of the highest complete correlation coefficients among five climatic regions. During 1961-2013, wind speed became the biggest contributor in XinJiang and this was also apparent in the south slope of Tianshan Mountains, the north slope of Tianshan Mountains and the north foot of Kunlun Shan; while relative humidity was the biggest contributor in the Altay Mountains. From 1961 to 1994, hours of solar shine was the biggest contributor, whereas during 1994-2013, temperature became the biggest contributor in the Altay Mountains. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Evapotranspiration
Controlled terms:Atmospheric humidity - Climate change - Dynamics - Global warming - Irrigation - Landforms - Meteorology - Spatial distribution - Water resources - Water supply - Wind
Uncontrolled terms:Arid and semi-arid areas - Contribution analysis - Correlation coefficient - Irrigation water supply - Penman-Monteith equations - Potential evapotranspiration - Spatiotemporal variability - Xinjiang
Classification code:443 Meteorology - 443.1 Atmospheric Properties - 444 Water Resources - 444.1 Surface Water - 446.1 Water Supply Systems - 481.1 Geology - 821.3 Agricultural Methods - 921 Mathematics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.022
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 30>
Accession number:20151000594734
Title:Winter wheat yield estimation based on assimilation method combined with 4DVAR and EnKF
Authors:Xie, Yi (1); Wang, Pengxin (1); Liu, Junming (1); Li, Li (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing, China
Corresponding author:Liu, Junming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:187-195
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The CERES-Wheat model is used to simulate leaf area index (LAI) of winter wheat for reflecting accurately the growth of winter wheat and estimating the yield. But it is difficult to simulate wheat yield at a large area with CERES-Wheat model because of the lack of regional input parameters. Data assimilation algorithm is an efficient method to combine crop growth model and remote sensing data and it solves the shortcoming of CERES-Wheat model by taking advantage of macro of remote sensing data. NASA's Moderate Resolution Imaging Spectroradiometer (MODIS) data is normally used in assimilation with crop growth model for yield estimation; but the spatial resolution of MODIS is low, and the estimation accuracy of crop will be reduced by the mixed pixel problem, as the farmland is small. Landsat remotely sensed data with a spatial resolution of 30 m would be helpful to make crop yield estimation at field scale in China, and TM and ETM+ remotely sensed data were both used in assimilation for solving the disadvantage of low temporal resolution of Landsat. The CERES-Wheat model was used to simulate LAI of the whole growth period of winter wheat in Guanzhong Plain of Shaanxi province. The assimilation of simulated LAI with LAI retrieved from TM and ETM+ data was carried out in eight typical sampling sites by using two data assimilation approaches, the four-dimensional variational (4DVAR) and ensemble Kalman filter (EnKF). The assimilated LAI image of the whole study area was achieved by employing the linear correlation model between remotely sensed LAI and assimilated LAI of the eight sampling sites. After establishing the assimilation system, the remotely sensed LAI and the simulated ones of the eight sampling sites were used to test the two assimilation approaches. The result showed that the assimilated LAI values of the sites were more accurate and closer to the real ones after combining the advantages of both remotely sensed LAI and simulated LAI. In order to utilize a more accurate assimilation algorithm for estimating yield of winter wheat in Guanzhong Plain, the 4DVAR and EnKF approaches were compared and analyzed for both assimilated LAI values of the sites and assimilated LAI images of the two assimilation approaches. The root mean square error (RMSE) between EnKF-LAI values and measured LAI values of the sites was 0.41, while the RMSE of 4DVAR-LAI values was 0.55, so EnKF-LAI values of the eight sites were closer to the measured ones than those of the 4DVAR-LAI. After comparing assimilated LAI images from 4DVAR and EnKF approaches, it concluded that the EnKF-LAI images were more in line with spatial distribution characteristics of winter wheat's LAI in Guanzhong Plain, and the EnKF algorithm was an appropriated approach for assimilating LAI. The EnKF-LAI images of 4 main growth stages of winter wheat including the reviving stage, jointing stage, heading-filling stage and dough stage were used to estimate winter wheat yield of the whole plain by constructing winter wheat yield estimation model. By comparing with the measured yields of winter wheat in the crop year of 2007-2008, the relative errors (RE) of the estimated yields of the eight sites were from 2.05% to 14.57% with an average of 9.15%, and the RMSE between the estimated and measured yields was 596.7 kg/hm<sup>2</sup>. While the RE between the simulated and measured yields was from 8.80% to 36.61% with an average of 22.13%, and the RMSE was 1699.0 kg/hm<sup>2</sup>. In addition, wheat yields in the crop year of 2013-2014 were used for further validation of the winter wheat yield estimation model. Compared with the RE between the simulated and measured yields, the RE between the estimated and measured yields was decreased by 0.57%-9.30%, with an average relative error reduction of 3.89% in the 15 sampling sites; and the estimated accuracies in the 8 sampling sites are larger than 94%. These show that the estimated yields of the sampling sites are close to the measured ones, and the accuracy of the yield estimation model is obviously improved. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Crops
Controlled terms:Estimation - Image reconstruction - Image resolution - Mean square error - Models - NASA - Radiometers - Remote sensing - Satellite imagery
Uncontrolled terms:Assimilation - Data assimilation algorithms - Distribution characteristics - Four dimensional variational - Leaf Area Index - Linear correlation model - Moderate resolution imaging spectroradiometer datum - Yield
Classification code:443 Meteorology - 655 Spacecraft - 656 Space Flight - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 742 Cameras and Photography - 821.4 Agricultural Products - 902.1 Engineering Graphics - 921 Mathematics - 944.7 Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2015.01.026
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 31>
Accession number:20151000594727
Title:Non-point source pollution control experiment and ecological response of ecological landscape type irrigation and drainage system
Authors:Zhang, Yajie (1); Shao, Qingjun (1); Li, Haicai (1); Ye, Liangqian (1); Yao, Xing (1); Hu, Jiangjun (1)
Author affiliation:(1) School of Resource and Environmental Science, Wuhan University, Wuhan, China
Corresponding author:Shao, Qingjun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:133-138
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The current irrigation and drainage system in land renovation was mainly designed and constructed to heighten efficiency of irrigation and drainage, structure safety and convenient management, which, however, somewhat neglected ecological landscape design, exerting an inappropriate influence on the biological habitat and agricultural non-point source pollution. Therefore, the aim of this paper is to design an ecological landscape irrigation and drainage system and realize more comprehensive benefits. First of all, originated from the traditional agricultural drainage and irrigation system, irrigation and drainage with an ecological ring-ditch was designed by using the principle of mutually-beneficial symbiosis of paddy, red duckweed, fish and vegetable planting plates, which realized the multifunctional stereo development of rice paddy pisciculture, vegetable planting and so on. Meanwhile, the roundabout biochemical pond was designed at the ecological ring-ditch drainage sluice, which was used as the treatment device of agricultural non-point source pollution. Then, ecological landscape lateral canal and lateral ditch was designed, which was made up of vegetation type diaphragm blocks, hornworts, vegetable planting plates, fish, Jumping type antiskid ecological plate and plant ecological community. What is more, by using the land reclamation project in shanghai as the experimental area, the rice growth cycle (6-10 months) as study period, the COD, NH<inf>4</inf><sup>+</sup>-N, TN and TP as test indicators, and three monitoring sections as monitoring points, experimental of non-point source pollution prevention effects were made comparisons between system 1, system 2 and system 3. The system 1 was constituted by the irrigation and drainage system using ecological ring-ditch, roundabout biochemical pond and lateral ditch wetlands. The system 2 was constituted by the irrigation and drainage system using underground pipe and current lateral ditch. And the system 3 was constituted by the irrigation and drainage system using open channels and ditch and current lateral ditch. Finally, we introduced ecological service value model to evaluate ecological response of the ecological system of farmland water conservancy brought by the ecological landscape type of irrigation and drainage system. The results showed that: 1) The ecological landscape type of irrigation and drainage system consists ecological ring-ditch, roundabout biochemical pond and lateral ditch wetlands accompanied with the principle of mutually-beneficial symbiosis of paddy, red duckweed, fish and vegetable planting plates, realizing rice paddy pisciculture and agriculture modernization. It was a success not only for the farmland benefit but also providing the important practical significance of exploring environmentally friendly high-efficiency systems for ecological agricultural uses; 2) The average removal rate of ecological landscape type of irrigation and drainage system were77.57%, 78.99%, 69.77%, 73.74% respectively. Firstly, red duckweed, vegetable planting plates, microbial can degrade pollutants in the ecological ring-ditch; Secondly, biochemical pond removed pollutants with the absorption and transformation by microorganism and plants, as well as sedimentation and filtration; Finally, the lateral ditch removed pollutants through microbial absorption and transformation, sedimentation and filtration, matrix adsorption and so on; 3) A big ecological response was generated from the ecological system of farmland water conservancy brought by the ecological landscape type of irrigation and drainage system. The positive effect was 49.4×10<sup>3</sup> yuan, which is 45 times than the negative effect. In conclusion, the ecological function of the ecological landscape type of irrigation and drainage system was enhanced in climate regulation, water conservation, waste disposal, biodiversity conservation, soil conservation and aesthetic landscape and so on. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:12
Main heading:Ecosystems
Controlled terms:Agriculture - Biodegradation - Biodiversity - Conservation - Drainage - Ecology - Farms - Fish - Irrigation - Lakes - Land reclamation - Land use - Linear transformations - Plants (botany) - Plates (structural components) - Pollution - Pollution control - Soil conservation - Vegetables - Waste disposal - Water absorption - Water conservation - Water filtration - Water management - Water pollution - Wetlands
Uncontrolled terms:Agricultural non-point source pollutions - Biodiversity conservation - Ecological response - Ecological service values - Farmland water conservancies - High efficiency system - Irrigation and drainage systems - Non-point source pollution
Classification code:401 Bridges and Tunnels - 406 Highway Engineering - 407 Maritime and Port Structures; Rivers and Other Waterways - 408.2 Structural Members and Shapes - 442 Flood Control; Land Reclamation - 442.2 Land Reclamation - 444 Water Resources - 446 Waterworks - 452.4 Industrial Wastes Treatment and Disposal - 453 Water Pollution - 454 Environmental Engineering - 461.8 Biotechnology - 461.9 Biology - 502 Mines and Quarry Equipment and Operations - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.3 Mathematical Transformations
DOI:10.3969/j.issn.1002-6819.2015.01.019
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 32>
Accession number:20151000594736
Title:Recognition of hazard grade for cotton blind stinkbug based on Naive Bayesian classifier
Authors:Zhai, Zhifen (1); Xu, Zhe (1); Zhou, Xinqun (1); Wang, Lili (1); Zhang, Jianhua (2)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing, China; (2) Agriculture Information Institute, Chinese Academy of Agricultural Science, Beijing, China
Corresponding author:Zhang, Jianhua
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:204-211
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cotton, one of the most important economic crops in our country, always suffers a variety of pest during the whole process of planting. Blind stinkbug, which seriously affected the cotton quality and yield during BT cotton, is planted in large areas of the Yellow River and Xinjiang province in China. Traditional cotton blind stinkbug hazard ration identification method relies too much on experience, but recognition accuracy and recognition speed are low. In view of complex background of cotton blind stinkbug hazard region and the difficulty in segmentation and classification under natural conditions, an automatic classification method of Cotton blind stinkbug hazard level was proposed. On the basis of the classification standard of plant diseases and insect pests and hazard characteristics of cotton blind stinkbug, as well as the harm degree distribution of bug to cotton by artificial statistics, the cotton blind stinkbug damage grade was divided and the damage grade standard of bug to cotton was put forward. The processing steps of the cotton leaf image in different bug damage grade acquainted in natural conditions were as follows. Firstly, by using Q color component and Otsu segmentation method, the image background was divided. Secondly, in order to remove burrs after splitting, morphological opening operation and internal filling algorithm were used to deal with the segmented image, and the largest connected component was extracted, which can eliminate the influence of weeds. Thirdly, the disease regions of cotton were extract by H+a*+b* component and Otsu segmentation method based on blind stinkbug hazard cotton leaves. The adhesion cotton leaves were separated by Watershed segmentation method Forth, and extracted and selected contents including the color, texture and shape features of and cotton leaf hazard by blind stinkbug. In accordance with the principle of distinction and difference, color feature, texture feature and shape feature was the input indicators classifier. Based on the statistical results of color, texture and shape feature of bug damage image to cotton, R component, G component, B component, I1 component, S component and V component were selected as the color feature, Contrast and Correlation were selected as the texture feature, Pa value were selected as the shape feature. Finally, based on Matlab R2008 platform, combined with the bug feature variables and naive Bias classifier extraction, this method had the aim to distinguish the cotton blind stinkbug damage grade based on the cotton bug division of the harm grade standard. In this experiment, 120 cotton blind stinkbug damage leaves image with 6 levels were used for simulation, in which 60 images were the training set and the others were the validation set. Different bug harm level recognition experiment results showed that, the model has advantages in accuracy and speed with average rate of correct recognition as 90% and average operation time as 0.278 seconds, which was better than Support vector machine and BP neural network model. The proposed cotton blind stink bug hazard grade standard can provide a theoretical basis for the study of harmful cotton blind stinkbug. The proposed classification method of cotton blind stinkbug hazard rating will not only promote technical level for the prevention and treatment of the cotton blind stinkbug, but also it provides a reference for the identification and control of other pests. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Cotton
Controlled terms:Classification (of information) - Color - Color image processing - Complex networks - Hazards - Image processing - Image segmentation - MATLAB - Models - Neural networks - Plants (botany) - Textures
Uncontrolled terms:Automatic classification - Blind stinkbug - Classification standard - Hazard rating - Largest connected component - Naive Bayesian Classifier - Plant diseases and insect pests - Recognition
Classification code:461.1 Biomedical Engineering - 461.9 Biology - 716.1 Information Theory and Signal Processing - 722 Computer Systems and Equipment - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 819.1 Natural Fibers - 902.1 Engineering Graphics - 914.1 Accidents and Accident Prevention - 921 Mathematics - 933 Solid State Physics
DOI:10.3969/j.issn.1002-6819.2015.01.028
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 33>
Accession number:20151000594712
Title:Design and experiment of V-L shaped smashed straw blade
Authors:Jia, Honglei (1); Jiang, Xinming (1); Guo, Mingzhuo (1); Liu, Xiaoliang (1); Wang, Lichun (1)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun, China; (2) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China; (3) Jilin Academy of Agricultural Sciences, Changchun, China
Corresponding author:Wang, Lichun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:28-33
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A smashed straw blade with V-L shaped for smashed straw machine was designed based on analyzing the advantages and disadvantages of existing blades, such as straight-knife shaped, Y or L shaped and hammer shaped. It can solve the problems in practical operation, such as obvious abrasion, fierce machine vibration, unsatisfied smash effect and poor stability. We improved L shaped blade by adding a V-bending to form V-L structure. The V-L structure can decrease the included angle between edge line and ground to avoid wear too fast, extend the length of edge line to reduce blade density, move the barycenter outward to increase rotational inertia and ensure the barycenter located in the same plane with blade handle to improve rotation stability. The barycenter position was not affected by blade thickness, the blade mass increased and the deformation decreased with increase of blade thickness based on finite element analysis by Inventor software. To increase rotational inertia and prevent the deformation of blade, we confirmed the blade thickness was 8 mm. The maximum deformation was 0.16 mm and the minimum safety factor was 6.86. To offset the sliding cutting angle when the blade turned backwards, the forward inclination was designed. It was determined between 10° and 15° via the soil-bin test. The material of blade was 65Mn and the edge angle was 30°. Autogenously grinding edge was designed by medium-frequency hardening of edge. The working parameters of blade were determined based on analyzing the influences of tractor forward speed, roller revolving speed and interaction between them on straw smashing rate. The test results showed that the straw smashing rate decreased with increase of tractor forward speed and increased with increase of roller revolving speed. As for the interaction between tractor forward speed and roller revolving speed, straw smashing rate increased with decrease of forward speed and increase of roller revolving speed. The optimal combination was that the forward speed was 1 m/s and the roller revolving speed was 1400 r/min by using the Origin software. The experiment of two factors and three levels was conducted taking forward speed and roller revolving speed as experimental factors, straw smashing rate as experimental indices. The optimal combination was that the forward inclination was 10° and the included angle between edge line and ground was 14° based on the range analysis and variance analysis. The interaction between forward inclination and included angle between edge line and ground was not significant. The blade cutting width of 89.8 mm and the gyration radius of 170.6 mm were determined according to included angle between edge line and ground. The field test was conducted to verify the operation effect of smashed straw machine. The qualified rate of straw smashing length between and in the ruts was 93.43% and 95.35% respectively, the average stubble height was 61 mm, the unevenness of straw dispersal was 14.7% and the pure productivity was 0.48 hm<sup>2</sup>/(m·h). The test results showed that the smashed straw machine can meet the requirements of national standards. But the vibration performance and power consumption of smashed straw machine need to study further. The study can provide a reference to design the smashed straw blade. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Speed
Controlled terms:Agricultural machinery - Automobile testing - Cultivation - Deformation - Design - Experiments - Finite element method - Machine design - Rollers (machine components) - Safety factor - Straw - Tractors (agricultural) - Tractors (truck)
Uncontrolled terms:Blade - Experimental factors - Medium frequencies - Minimum safety factor - Optimal combination - Sliding cutting angles - Tractor forward speed - Working parameters
Classification code:408 Structural Design - 408.1 Structural Design, General - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 601 Mechanical Design - 601.2 Machine Components - 662 Automobiles and Smaller Vehicles - 662.1 Automobiles - 663 Buses, Tractors and Trucks - 663.1 Heavy Duty Motor Vehicles - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 921.6 Numerical Methods - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2015.01.004
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 34>
Accession number:20151000594711
Title:Design and experiment of cleaning performance in a centralized pneumatic metering device for maize
Authors:Qi, Bing (1); Zhang, Dongxing (1); Liu, Quanwei (1); Yang, Li (1); Shi, Song (1); Cui, Tao (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing, China; (2) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture, Nanjing, China
Corresponding author:Yang, Li
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:20-27
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Precision planting is an advanced planting approach and a necessary way to achieve agricultural modernization and also an important step to increase crop yield. Precision metering device is a key component to realize precision planting, which is divided into two types according to its working principle. One type is mechanical metering device and the other type is pneumatic metering device. Compared with mechanical metering device, pneumatic metering device has the advantage of extensive use-area, strong currency, no damage to seed and lower requirement of seed geometry, so pneumatic metering device has been widely applied both at home and abroad. Centralized pneumatic metering device for corn is one type of pneumatic metering device which is applied in large scale planter. It can realize the "one seed metering device to many rows" precise seeding and improve efficiency of seeding. However, there exists a problem that reseeding rate is too high when seeding speed range between 4 km/h and 8 km/h. To solve the problem, a new seed eliminator in radial direction was developed for matching the rotary drum metering device. Analysis was made on radial eliminating process and seed motion process in positive rotary drum and kinematic equations were established of seeds uniform circular motion when seed-filling process finished. According to the analysis, a conclusion was made that the main influencing factors of cleaning effect were speed of the rotary drum ω and diameter of seed-filling hole d<inf>h</inf> based on area occupied ratio conception. In addition, the result showed that the diameter of seed-filling hole d<inf>h</inf> was the most important influencing factor of occupied area. To meet the demand that seeds should not be blocked when their smallest parts went through the eliminating driving finger, length of eliminating finger l<inf>b</inf> was determined to 20 mm. Besides, angle of the end eliminating driving finger was determined to 20° based on the maximum static force of friction. In order to determine the proper distance between eliminating driving finger and seed-filling hole, experiments on eliminating distance optimization were done in seed-meter performances test platform of typed JPS-12, and the experimental material was maize zhengdan No. 958. Vortex fan was used to supply airflow for the device, and the pressure in working chamber was measured by airflow pressure meter of typed KA33. Results indicated that the eliminating distance in the range from 0.25 to 2.75 mm had no significant influence on the miss-seeding rate, but had highly significant influence on the re-seeding rate and the qualified seeding rate. The re-seeding rate decreased significantly as the eliminating distance range from 2.75 mm to 0.25 mm, with the eliminating distance for negative 0.25 mm. The miss-seeding rate sharply rose up to 5.83%, but the re-seeding rate significantly decreased. The optimized eliminating distance was determined as 0.25 mm, so the eliminating distance was determined as 0.25 mm. Comparative experiment showed that the rate of single seed always kept at above 96% under the optimized eliminating distance as the forward velocity range from 4 to 12 km/h. In detail, the miss-seeding rate generally kept consistent, but the re-seeding rate obviously decreased. The seed eliminator can effectively reduce the multiple rate of the centralized pneumatic metering device. The research can provide a reference for structure design and optimization of working parameters in same type device. The designed device has advantages of seed- and labor-saving as well as the good social and economic benefits. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Pneumatics
Controlled terms:Agricultural machinery - Agriculture - Economics - Filling - Motion analysis - Optimization - Seed - Structural optimization
Uncontrolled terms:Eliminating distance - Eliminating finger - Metering devices - Rotary drum - Seed filling
Classification code:632.3 Pneumatics - 691.2 Materials Handling Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2015.01.003
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 35>
Accession number:20151000594744
Title:Farmland change induced land and water resource balance in Naoli River Basin from 1990 to 2013
Authors:Zhou, Hao (1); Lei, Guoping (1); Zhang, Bo (1); Zhao, Yuhui (1); Zhang, Xu (1); Dong, Bowen (1)
Author affiliation:(1) College of Resource and Environment, Northeast Agricultural University, Harbin, China; (2) Land Management Institute, Northeastern University, Shenyang, China
Corresponding author:Lei, Guoping
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:272-280
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Since early 1990s, the agricultural structure of Naoli River Basin has been greatly adjusted with large amount of dry land changed into paddy field. This resulted in a set of problems in the utilization of water resources. To reveal the water profit and loss situation of the cultivated land resources in this river basin, the dynamic changes between the dry land and paddy field was analyzed and the farmland water requirements of the cultivated land in this basin was calculated in this article. By modeling the rice planting proportion coefficient which could show the structure of cultivated land, and using the contribution rate that was borrowed from the thought of economics, combing the results of established various types of crop, which was from the research of other scholars, the rate of paddy field and dry land proportion was determined. The remote sensing image data, the long-term sequenced meteorological data and the DEM data were used as its fundamental data resources in all the above analysis. By combining the planar climatic elements data which was attained from the dot data interpolation processing, the Penman-Monteith Model was used to create the computational condition of reference evapotranspiration (ET<inf>0</inf>), which was generally agreed upon in the academic circles, the related model was used to analyze and compute the actual evapotranspiration (ET) for the condition of Naoli River basin, evaluation model of water profit and loss degree was established, and the order of evaluation standard was also structured to analyze the variation of area changes at different levels of moisture shortage. Fastly, the balance effect questions between the soil and water resources under the situation where the cultivated land constantly changed in the basin between 1990 and 2013 were discussed in this article. Results showed that the changes between the paddy field and the dry land in the Naoli River Basin were incredibly violent. The internal transformations between the paddy field and dry land were the primary changes. The dry land was the main source land for the increase of the paddy field; the farmland water requirements also increased from 541 mm in 1990 to 581.82 mm in 2013. These changes were mainly concentrated in the northwest and middle regions of this river basin and the range of the annual actual evapotranspiration was between 438-587 mm. Its overall distribution characteristic manifested itself as 'middle low, two ends high'; the change degree of the cultivated land's water profit and loss were obvious and the spatial distribution differences of the profit and loss index for evaluation grades were great. Except for the slight increase of the cultivated land with serious water shortage, the cultivated land area of the rest four evaluation grades all changed strongly. Among them, the area proportion of cultivated land with normal water shortage decreased 22.06% and the area proportions of cultivated land for the rest three evaluation grades all increased 4.74%, 9.61% and 7.72% successively. The above statement shows that the water deficit of the cultivated land in this river basin has been further intensified. These research results provide the references and consultancies for the farmland irrigation schemes in the Naoli River Basin. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Water resources
Controlled terms:Data handling - Economics - Evapotranspiration - Farms - Image reconstruction - Land use - Meteorology - Profitability - Remote sensing - Rivers - Water supply - Watersheds
Uncontrolled terms:Actual evapotranspiration - Distribution characteristics - Evaluation modeling - Farmland - Penman-Monteith models - Reference evapotranspiration - Remote sensing images - River basins
Classification code:403 Urban and Regional Planning and Development - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 446.1 Water Supply Systems - 723.2 Data Processing and Image Processing - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics
DOI:10.3969/j.issn.1002-6819.2015.01.036
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 36>
Accession number:20151000594740
Title:Advances in methods and instruments for determining concentration of gaseous air pollutants in large-scaled livestock farms
Authors:Jie, Dengfei (1); Pan, Jinming (1); Ying, Yibin (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China; (2) College of Engineering and Technology, Huazhong Agricultural University, Wuhan, China
Corresponding author:Ying, Yibin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:236-246
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the development of Chinese large-scale and intensive livestock production, the animal stocking density increases, resulting in a lot of pollutant gas emissions. They are not only the important sources of greenhouse gas (GHG) emissions such as carbon dioxide (CO<inf>2</inf>), methane (CH<inf>4</inf>), nitrous oxide (N<inf>2</inf>O), but also the sources of nitrogen or sulfur organic odors such as hydrogen sulfide (H<inf>2</inf>S), ammonia (NH<inf>3</inf>), mercaptan, phenol, paracresol, indole, skatole, which are produced by manure fermentation and decomposition. These gases contain large amounts of toxic and hazardous ingredients. If the concentration of pollution gas is small, the gas can be diluted by diffusion after emitting into the air. If the gas fails to be cleaned up or improperly handled, the odors will keep increasing and gather together. These gases will affect the growth of livestock and poultry, and they will cause environmental pollution, seriously affecting the air quality in urban and rural areas when these contaminated gases largely diffuse into the atmosphere. The environment could be deteriorating; the health of the feeders and residents also could be influenced. This paper reviewed the characteristics of several typical pollutant gases mainly including NH<inf>3</inf>, H<inf>2</inf>S, volatile organic compounds (VOCs) and other toxic and harmful gases. We also reviewed the research status of the pollution detection methods and analytical instruments at home and abroad for determining pollutant gas discharged from large-scale livestock and poultry breeding. Along with the development of computer technology, spectral analysis technology, sensor technology and wireless communication technology, there are more researchers applying the novel techniques on pollutant gas emissions from livestock farms in the domestic and foreign. This review synthesized the development of the methods and analyzers for the component and concentration detection of the gases emitted from livestock farms. According to the principal of the detection methods, the detection methods can be classified into optical methods and chemical methods. Optical methods can be divided into two types. One is the conventional optical method that determines the concentration of the pollution gas through measuring the light intensity change; the other is the spectral method that obtains the spectral information on the pollution gas using the spectrum analyzer. Chemical methods mainly include electrochemical method, chemiluminescence method, chromatography and mass spectrometry. In accordance with the measurement methods we summarized the type and origin of the instruments, the corresponding usage in the researches and the research findings using these instruments. In the end we compared the technical characteristics and application between internal and external situation. The goal of this review is for providing the basis to quick and accurate detection methods of the pollutant gases, which include the gases composition and concentration determination, and gives a reference for the development of pollution gas detection technology in livestock farming. To develop detection technology and integration system in situ, which can simultaneously detect all varieties of pollution gases emitted from livestock husbandry, will be the direction for the instrument and equipment development of livestock farm's gas emission detection in future. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:79
Main heading:Pollution detection
Controlled terms:Agriculture - Air pollution - Air quality - Carbon dioxide - Chemical detection - Chromatography - Gas emissions - Gases - Greenhouse gases - Instrument testing - Instruments - Mass spectrometry - Methane - Nitrogen - Nitrogen oxides - Odors - Optical engineering - Pollution - Rural areas - Spectrum analysis - Spectrum analyzers - Sulfur dioxide - Testing - Urban growth - Volatile organic compounds - Wireless telecommunication systems
Uncontrolled terms:Analytical instrument - Concentration detections - Concentration determination - ELectrochemical methods - Environmental pollutions - Equipment development - Methods - Wireless communication technology
Classification code:403.1 Urban Planning and Development - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 451 Air Pollution - 454.2 Environmental Impact and Protection - 522 Gas Fuels - 716 Telecommunication; Radar, Radio and Television - 717 Optical Communication - 741 Light, Optics and Optical Devices - 801 Chemistry - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2015.01.032
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 37>
Accession number:20151000594748
Title:Fresh-keeping effect of different coating materials on clean egg
Authors:Gu, Fenglan (1); Zhang, Jianhao (1); Ma, Lei (1); Long, Men (2); Huang, Mingming (1); Yang, Longping (1)
Author affiliation:(1) Food Safety and Nutrition Collaborative Innovation Center, College of Food Science and Technology, Nanjing Agricultural University, Nanjing, China; (2) College of Biological and Food Engineering, Chuzhou College, Chuzhou, China
Corresponding author:Zhang, Jianhao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:303-310
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nano-α-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material which had been researched by our lab team before had good antibacterial properties and water-resisting performance. On the basis, this paper will study whether the nano-α-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material could extend shelf life of clean eggs or not. Uncoated clean eggs were chosen as control group. Secondary soaking coating method were adopted to coat eggs and the coating process was putting clean eggs into coating liquid for one minute, and being taken out and then being blowing dried, and did the above-mentioned process again. All eggs were preserved in same preserved condition whose temperature and the relative humidity changed as time went on for 42 days. During storage the physical and chemical indicators include the yolk index, Haugh unit, albumen pH, and the egg weight loss were detected every week to determine the egg freshness. The other materials, polyvinylidene chloride and nano-Fe<sup>3+</sup>/TiO<inf>2</inf> and lac modified polyvinyl alcohol based material, were used as two control groups compared with nano α-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material. Their characteristics, e.g. antibacterial properties and water-resisting performance had been studied before. After storage for 42 days eggs were coated by nano-Fe<sup>3+</sup>/TiO<inf>2</inf> and lac modified polyvinyl alcohol based material (C group) whose egg grade was B, yolk index was 0.29, Haugh unit was 56.95, and albumen pH value was 9.32, and fresh eggs rate was 100% and the weight loss rate was 3.33%. The clean eggs coated by nano α-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material (B group) had 100% of fresh eggs rate, 3.05% of the weight loss rate, had A egg grade, 0.32 of Yolk index, 60.788 of Haugh unit, and 9.2 of albumen pH value, 1.9×10<sup>3</sup> CFU/mL of total plate count, and were superior to control group and other treatment groups. However, the yolk of A group (eggs coated by Poly vinylidene chloride) spreaded out at 35 days and control group (CK group) was at 28 days. The initial values of A group such as the egg weight loss rate and yolk index and albumen pH were better than other groups, and after 21 days storage they were worse than the other coating groups. The results showed that the quality of coating eggs were better than the eggs of control group under the same storage conditions, and the eggs coated by nano-a-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material had the best quality. The change of temperature and humidity would influence material barrier performance e.g. the preservation effect of polyvinylidene chloride reduced as humidity changed. In addition, the cost of nano-α-Fe<inf>2</inf>O<inf>3</inf> and beeswax modified polyvinyl alcohol based composite material was lower and its operation process was simple, so that it would have the prospect of industrial application. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:36
Main heading:Storage (materials)
Controlled terms:Chlorine compounds - Coatings - Composite materials - Energy storage - Indicators (chemical) - pH - Polyvinyl alcohols - Polyvinyl chlorides - Polyvinylidene chlorides - Quality control - Waxes
Uncontrolled terms:Antibacterial properties - Barrier performance - Change of temperatures - Operation process - Storage condition - Total plate count - Vinylidene chloride - Weight loss rates
Classification code:415 Metals, Plastics, Wood and Other Structural Materials - 539 Metals Corrosion and Protection; Metal Plating - 694.4 Storage - 702 Electric Batteries and Fuel Cells - 801 Chemistry - 801.1 Chemistry, General - 804 Chemical Products Generally - 811 Cellulose, Paper and Wood Products - 815.1.1 Organic Polymers - 913.3 Quality Assurance and Control - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.040
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 38>
Accession number:20151000594735
Title:Segmentation method of overlapped double apples based on Snake model and corner detectors
Authors:Xu, Yue (1); Li, Yinghui (1); Song, Huaibo (1); He, Dongjian (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, China
Corresponding author:Song, Huaibo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:196-203
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To achieve successful segmentation of overlapped apples, a segmentation method by using Snake model and corner detectors was presented. As contour is an important basis for detection and recognition of object, and remarkable characteristic of overlapped apples has some typical angular points, which are also called segmentation points and in the target contour. Since Snake model could better converge to target's concave places, Snake model was used to extract overlapped apples' outline. For searching overlapped apples' corner points, corner detection algorithm based distance was proposed: 1) overlapped apples' contour was coded; 2) the distance between contour points and the given 'center point' was calculated, where 'center point' was overlapped apples' centroid point for the simplicity of calculation; 3) the distance curve that was get in step 2 is useless as it may engender a lot of spurious corner points. This is caused by small disturbances of small distance, for removing spurious corner points, db1 wavelet was utilized to decomposed original signal at level three, there is a relationship between wavelet transform and digital filter banks. so the wavelet transform can be simply achieved by a tree of digital filter banks. The idea behind filter banks is to divide a signal into two parts: one is the low frequency part and the other is the high frequency part, which could be achieved by a set of filters, the low frequency that is approximate version of the original distance curve in this paper don't contain detail components of original distance and is beneficial to detect true corner points. But the problem with the use of these filters is that each of the two decomposed signals is subjected to downsampling, which simply means throwing away every second data point. After decomposition with three levels, the length of approximated signal reduced, which may cause the miss of the index of original contour point. As for this reason, the approximated signal must be recovered to its original length. In this paper, the interpolation algorithm with the use of splines is carried out to recover the length of approximated signal; 4) corner points represent the enormous changes of curvature and is shown the maximum or minimum on the distance curve, therefore, corner points can be detected by calculating the extrimum of distance curve. Detected corner points need to be selected to determine overlapping positions, a segmentation method based long axis segmentation rule was proposed to choose segmentation line: 1) overlapped apples were divided into uniform two parts approximately by long axis; 2) segmentation line was chose by calculating the distance between bilateral corner points and centroid point. Some split criteria were given as: 1) the direction of the detected points should be opposite, which meant that the detected points from the same region should not be used to split an object; 2) the length of split line should be short. By using these given criteria, the detected corner points were matched to realize the segmentation of overlapped apples. To validate the effectiveness of the algorithm, 20 overlapped apples in nature scenes were tested. Compared with segmentation line obtained by artificial calculation, highest segmentation error of the proposed method is 13.27°, minimum error is 1.20°, and the average error 6.41°. Experimental results show that the proposed segmentation algorithm has a preferable performance, and it is feasible and valid for overlapped apple segmentation in nature scenes. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Image segmentation
Controlled terms:Algorithms - Digital filters - Edge detection - Filter banks - Fruits - Image reconstruction - Interpolation - Low pass filters - Object detection - Signal detection - Signal processing - Time varying networks - Wavelet transforms
Uncontrolled terms:Corner detector - Interpolation algorithms - Long axis - Overlapped apples - Recognition of objects - Segmentation algorithms - Segmentation methods - Snake model
Classification code:703.1 Electric Networks - 703.2 Electric Filters - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 821.4 Agricultural Products - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2015.01.027
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 39>
Accession number:20151000594729
Title:Experiment and simulation on soil Cr(VI) loss to surface runoff under condition of nonlinear Langmuir adsorption
Authors:Wu, Xiujie (1); Tong, Juxiu (1); Tan, Chaoqun (1)
Author affiliation:(1) Key Laboratory of Groundwater Cycle and Environment Evolution (China University of Geosciences (Beijing), Ministry of Education, Beijing, China; (2) College of Water Resources and Environmental Sciences, China University of Geosciences (Beijing), Beijing, China
Corresponding author:Tong, Juxiu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:146-152
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Farmland has become less and less in China, but the heavy metal pollution is very serious recently. So, the study on the loss of adsorptive solute of six-valence chromium, i.e. Cr(VI) from soil to surface runoff becomes very important, which is of great significance to understand the expansion of heavy metal pollution in the field. The problem of chromium pollution has been a very serious and worldwide concern recently. In this paper, based on the water balance and solute mass conservation, a simple two-layer incomplete mixing model is used to study adsorptive solute of Cr(VI) loss from soil into surface runoff with nonlinear Langmuir adsorption. Based on the water infiltration, the rainfall process is divided into four stages. Experimental data under the condition of laboratory simulated rainfall-runoff is used to verify the model with nonlinear Langmuir isotherm adsorption equation. Influences of model parameters on the soil solute loss to surface runoff and model sensitivity are analyzed. The results suggest that model simulations with Langmuir isotherm equation agree well with the observed data, which means that the simple two-layer incomplete mixing model is reliable to predict the adsorptive solute of Cr(VI) loss from soil into surface runoff with nonlinear Langmuir adsorption. Parameters γ, which is the incomplete mixing parameter of the solute between the infiltration water and the soil water in the mixing layer, is more sensitive than α which is the incomplete mixing parameter of the solute between the soil water in the mixing layer and the ponding-runoff water. The parameters γ and α have a greater impact on the simulated results of the model in the early stages and smaller impact in the late stages of rainfall, and the parameter B, which is related to the saturated adsorption capacity in nonlinear isotherm equation, has a greater impact on the simulated result in the early stages than the impact in the late stages of rainfall. The parameter C, which is related to the adsorption-desorption equilibrium constant for a reversible reaction and the saturated adsorption capacity adsorbed by single molecular layer in nonlinear isotherm equation, has a greater impact in the early rainfall stage, but a relatively greater impact than other parameters in the model in the later stages. Experimental data indicates that the solute concentration and amount is very small, which means the solute in the mixing layer does not transfer much into ponding-surface runoff layer. This is also proved by the small value of the simulated α, which also suggests that the most of lost solute of soil Cr(VI) is in the drainage water. The study results will provide references to prevent and reduce the agricultural non-point heavy metal pollution in the field. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Infiltration
Controlled terms:Adsorption - Adsorption isotherms - Agricultural runoff - Chromium - Chromium compounds - Equilibrium constants - Heavy metals - Isotherms - Metals - Mixing - Nonlinear equations - Pollution - Ponding - Rain - Runoff - Soil conservation - Soil moisture - Soils
Uncontrolled terms:Adsorption desorption - Heavy metal pollution - Incomplete mixing - Langmuir adsorption - Nonlinear isotherms - Saturated adsorption capacity - Single molecular layers - Solute concentrations
Classification code:402 Buildings and Towers - 443.3 Precipitation - 444.1 Surface Water - 454.2 Environmental Impact and Protection - 483.1 Soils and Soil Mechanics - 531 Metallurgy and Metallography - 543.1 Chromium and Alloys - 801.4 Physical Chemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804.1 Organic Compounds - 821.5 Agricultural Wastes - 921.1 Algebra
DOI:10.3969/j.issn.1002-6819.2015.01.021
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 40>
Accession number:20151000594709
Title:Relationship analysis between agricultural engineering and agricultural modernization in China
Authors:Qi, Fei (1); Zhu, Ming (1); Zhou, Xinqun (4); Wei, Xiaoming (1)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing, China; (2) Xinjiang Academy of Agricultural Reclamation Sciences, Shihezi, China; (3) Key Laboratory of Farm Building in Structure and Construction, Ministry of Agriculture, Beijing, China; (4) Science and Technology Department, Chinese Academy of Agricultural Engineering, Beijing, China
Corresponding author:Zhu, Ming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:1-10
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Since 2003, Chinese agricultural and rural development has entered a golden period and a period of strategic opportunities. The report of 18th National Congress of Communist Party of China (CPC) proposes that the comprehensive goal of building a moderately prosperous society should be achieved in 7 years before 2020. To fulfill this objective, it is needed to make up the deficiency of agricultural development and accelerate development of agricultural modernization in China. However, in agricultural production, there are still a series of prominent contradictions and challenges between production resources and resource needs, between the product quantity and structure, between costs and benefits, between population and labor force, between infrastructure and natural disasters, and so on. All of these force the government to strength further the agricultural foundation, transform development pattern into a new path of intention-type agricultural development. One of primary tasks of China's modernization construction is to promote agricultural modernization. Agricultural engineering provides important technology support and substantial guarantee for the construction agricultural modernization. Recently, the improvement of agricultural engineering technology is increasingly correlated with development of agricultural modernization in China. According to the new strategy about promoting collaborative development of informationization, industrialization, urbanization and agricultural modernization (hereafter referred to as Four modernizations synchronization), agricultural modernization is involved in a more complicated giant social system, and the complexity, dynamics, openness and heterogeneity of the system are in accelerated growth. As a core element of China's agricultural modernization, agricultural engineering cannot develop well within its own isolated field. To be able to playing a better role and realizing win-win situation, the relationship and interaction between agricultural engineering and other systematical components have to be revealed in agricultural modernization. Based on the study about Chinese characteristic modern agriculture construction path, in combination with the theory, principle and methods of organized system and advanced productivity establishment, this study analyzed the systematic target and structure of China's agricultural modernization, and the status and function of agricultural engineering in the system and its relationship with other elements, structures and environment, in order to investigate the effect of the developing quantity, quality, momentum and structure of agricultural engineering on the developing quality and speed of agricultural modernization. The results showed that the development of agricultural engineering was greatly influenced by the development environment of agricultural modernization that included the macroscopic targets and polices related with national economy and society. The development of agricultural engineering was also restricted by the factors such as technology, talents, finance and management system. Meanwhile, agricultural engineering could improve the quality of core factors affecting agricultural modernization development including nature, policies, and society environment. Additionally, agricultural engineering had a significant impact on the structure of Chinese agricultural modernization development and showed positive correlations especially with the composition of the labor, land and products. In a word, the development mode of China's agricultural engineering needs to be changed. The period of strategic opportunity should to be well captured. The initiative and coordinate development of agricultural engineering can speed up the transforming of the development of modern agriculture, and create better developing environment and more opportunities for itself. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:37
Main heading:Agriculture
Controlled terms:Agricultural engineering - Construction - Disasters - Modernization - Multiprocessing systems - Professional aspects - Regional planning - Structure (composition)
Uncontrolled terms:Agricultural development - Agricultural modernizations - Agricultural productions - Collaborative development - Effect - Modernization construction - Relationship - System
Classification code:403.2 Regional Planning and Development - 405 Construction Equipment and Methods; Surveying - 484 Seismology - 722.4 Digital Computers and Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901 Engineering Profession - 901.1 Engineering Professional Aspects - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2015.01.001
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 41>
Accession number:20151000594752
Title:Effects of transport seasons on stress and meat quality of pigs
Authors:Zhen, Shaobo (1); Liu, Yiren (3); Guo, Huiyuan (2); Pan, Teng (2); Ren, Fazheng (2)
Author affiliation:(1) Higher Vocational and Technical College, China Institute of Industrial Relations, Beijing, China; (2) China Agricultural University, Beijing Higher Institution Engineering Research Center of Animal Product, Key Laboratory of Functional Dairy, Beijing, China; (3) Beijing Centre for Physical and Chemical Analysis, Beijing, China
Corresponding author:Ren, Fazheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:333-338
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pre-slaughter stress is both an animal welfare issue and a quality issue, as it has long been recognized that pre-slaughter stress can adversely affect the quality of pork. Pre-slaughter handling includes mixing of unfamiliar animals, loading, unloading, transportation and abattoir lairage. All these handling practices can induce stress. Transport season is a crucial factor governing the amount of animal stress and influencing the meat quality. It is known that cold and heat stress have an impact on ante-mortem and post-mortem muscle glycogen stores leading to higher incidence of DFD (dark, firm, dry) and PSE (pale, soft, exudative) pork respectively. Several studies on the effects of transport season on meat quality have been reported in the countries like UK or Denmark, where the climate conditions are relatively stable, but few studies was reported in regions of large temperature difference, and did not mention animal stress. In order to investigate the effects of transport seasons on the animal stress and meat quality of pigs, a total of sixty Duroc × Large White × Landrace pigs came from the same farm were transported in summer, autumn and winter in Beijing. The carcass skin blemish, blood biochemical parameters and blood constituents as the indicators of animal stress and the meat quality traits of pH value, temperature, color, drip loss, cooking loss and shear force were measured in this sutdy. The results showed that pigs transported in autumn presented lower white blood cells, hemoglobin, hematocrit, adrenocorticotrophic hormone, cortisol and glucose in blood compared with summer and winter (P<0.05). Carcass skin blemish scores were lowest in pigs transported in autumn (P<0.05). Plasma enzymatic activities of creatine kinase and lactic dehydrogenase were significantly higher in summer than the other groups (P<0.05). Lactate, mean corpuscular volume, mean corpuscular hemoglobin, mean corpuscular hemoglobin concentration and platelet count were not significantly different among the three groups (P>0.05). With the exception of b* and muscle temperature at 24h postmortem, transport seasons significantly influenced other meat quality parameters (P<0.05). Compared with autumn, pigs transported in summer showed significant higher muscle temperature at 45min postmortem, drip loss, cooking loss and L* value, the shear force and a* value dramatically reduced (P<0.05), while a* color coordinate value significantly increased in winter (P<0.05), drip loss and shear force had no significant difference (P>0.05). The research identified that the proper transport season for the test pigs in Beijing was autumn, both from the viewpoint of animal welfare and meat quality. Pigs transported both in summer and winter presented higher stress and worse meat quality. In conclusion, more attention should be paid to the effect of transport seasons on stress and meat quality in pigs in order to improve the animal welfare and obtain better pork quality. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:37
Main heading:Meats
Controlled terms:Animals - Blood - Food processing - Hemoglobin - Mammals - Muscle - Quality control - Stresses - Thermal processing (foods) - Unloading
Uncontrolled terms:Animal welfare - Biochemical parameters - Blood parameters - Enzymatic activities - Hemoglobin concentration - Seasons - Temperature differences - Water holding capacity
Classification code:421 Strength of Building Materials; Mechanical Properties - 461 Bioengineering and Biology - 461.2 Biological Materials and Tissue Engineering - 471 Marine Science and Oceanography - 674.1 Small Marine Craft - 814 Leather and Tanning - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822 Food Technology - 913.3 Quality Assurance and Control
DOI:10.3969/j.issn.1002-6819.2015.01.044
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 42>
Accession number:20151000594737
Title:Grading method of rice panicle blast severity based on hyperspectral image
Authors:Huang, Shuangping (1); Qi, Long (1); Ma, Xu (1); Xue, Kunnan (1); Wang, Wenjuan (3)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment (South China Agricultural University), Ministry of Education, Guangzhou, China; (2) School of Engineering, South Agricultural University of China, Guangzhou, China; (3) Plant Protection Research Institute, Guangdong Academy of Agricultural Sciences, Guangzhou, China
Corresponding author:Qi, Long
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:212-219
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Estimation of panicle blast level plays an important role in high-quality production of rice. It helps to quantitatively assess the level of blast resistance and severity in the field to make appropriate decisions in gauging cultivar resistance in rice breeding or precisely controlling blast epidemic. However, it is difficult to evaluate the blast disease degree automatically and accurately. In this study, a novel grading method for panicle blast severity based on hyperspectral imaging technology is proposed. The method defines a bag of spectrum words (BoSW) model for hyperspectral image data representation. The BoSW model based on hyperspectral image data representation is used as the input of a Chi-square kernel support vector machine (Chi-SVM) classifier for predicting the rice panicle blast level. More precisely, dense grids are firstly extracted over the spatial X-and Y-axes across the whole spectral Z-axis. The average spectrum curve of all the pixels within a grid cube is calculated. Then, K-Means clustering would be performed on the large collection of average spectrum curves from the training samples to form the dictionary of spectrum words. Next, each spectrum curve on the grid cube is quantized into one of spectrum words. Each hyperspectral image of rice panicle is transformed into a map of spectrum words. All the spectrum words are distributed evenly on the spatial XY-axis plane. BoSW model for each hyperspectral data cube is then formed by means of histogram statistics of spectrum word occurrences. Finally, a Chi-SVM classifier is trained using the BoSW representations of rice panicle hyperspectral images for predicting panicle blast infection levels. The proposed BoSW method uses both the image and full-spectrum information by means of regular grid cube extraction, which utilizes the full potential of the imaging sensing system. Meanwhile, the representation dimension for each hyperspectral image is significantly reduced, i.e. 100 here, and thus relieving modeling difficulty. The procedure of clustering helps to find the representative spectrum curves and quantizing helps to transform all the continuous-state spectrum curves into one of representative spectrum curve. Thus the proposed BoSW method is invariant to complicated noise and robust to rice cultivars. To verify the proposed BoSW method, a total of 170 fresh rice panicles covering more than 50 cultivars are collected from an experimental field for the performance evaluation. The experimental field is located in regional testing area for evaluating rice cultivars in Guangdong province. Therefore, all the rice plants in this area are naturally inoculated as the area is a typical source of rice blast fungus. The hyperspectral images of all the rice panicles are acquired using HyperSIS-VNIR-QE imaging spectrometer and then are transformed into 100-dimension BoSW representation for the construction of Chi-SVM classifier. Four-class label of hyperspectral image sample is determined by plant protection expert according to description of blast infection levels. Two thirds of the labeled BoSW representations are randomly selected for training and the rest for testing. Experimental results show that the proposed BoSW based method achieved high classification accuracy of 94.72%. This result is much better than traditional hyperspectral image analysis methods such as Principal component analysis (PCA), sensitive bands selection and etc. Moreover, the proposed BoSW demonstrates strong robustness to rice cultivars, which is vital for the wide and practical application. This research improves the classification accuracy of rice panicle blast grading and provides a reference to evaluate other disease level grading as well. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Blast resistance
Controlled terms:Diseases - Geometry - Grading - Image analysis - Image processing - Independent component analysis - Principal component analysis - Spectroscopy - Spectrum analysis - Support vector machines
Uncontrolled terms:Classification accuracy - Histogram statistics - Hyper-spectral images - Hyperspectral image analysis - Hyperspectral image datas - Hyperspectral imaging technologies - Imaging spectrometers - K-means clustering
Classification code:412 Concrete - 421 Strength of Building Materials; Mechanical Properties - 461.7 Health Care - 723 Computer Software, Data Handling and Applications - 723.4 Artificial Intelligence - 741 Light, Optics and Optical Devices - 801 Chemistry - 913.3 Quality Assurance and Control - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2015.01.029
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 43>
Accession number:20151000594726
Title:Generating 3D model of slope eroded gully based on photo reconstruction technique
Authors:Li, Junli (1); Li, Binbing (2); Liu, Fangming (1); Li, Zhanbin (3)
Author affiliation:(1) Graduate Management Group, Engineering University of CAPF, Xi'an, China; (2) Department of Information Engineering, Engineering University of CAPF, Xi'an, China; (3) College of Water Resources and Hydro-electric Engineering, Xi'an University of Technology, Xi'an, China
Corresponding author:Li, Binbing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:125-132
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Based on Structure from Motion (SFM) and Multi-View Stereo (MVS) techniques, this paper proposed a rapid 3d reconstruction method of slope eroded gully. Firstly, feature points were extracted and described by using the Scale-Invariant Feature Transform (SIFT), and then Random Sample and Consensus (RANSAC) algorithm was applied to filter inaccurate matching points generated by Nearest Neighbor (NN) algorithm; Secondly, in the condition that there were no camera parameters and scenario-based three-dimensional information, SFM was used because it provided a solution to iterate and get camera matrix and 3d point coordinates. During the iterating process, Bundle Adjustment (BA) algorithm was used for nonlinear optimizing and to ensure symmetrical distribution of the error in order to keep precision of the reconstructed model; After that, with the constraints of local photometric consistency and global visibility, Patch-Based Multi-View Stereo (PMVS) algorithm was adopted to expand sparse point cloud generated by SFM. Thus far the dense reconstruction of point cloud had finished. In order to validate the rationality and accuracy of using this method to monitor gully erosion, indoor runoff scouring experiment was conducted in "hydrology and water resources" laboratory at Xi'an University of Technology. Photos used in the reconstruction were taken by Canon 550d SLR camera. Because modeling process relied on tracking with the oriented point on the subject to determine the final 3d model of point set, so two adjacent photos' differential seat angle can't be too large, in case of losing trace points. Reasonable selection of photo shooting location, trajectory and angle should be considered according to the experimental environment and conditions. This paper used the VisualSFM software to complete detecting and matching of feature points, sparse reconstructing of point cloud as well as self-calibrating of camera; used CMVS and PMVS2 tools to finish dense reconstruction, and Meshlab to achieve visualization. After the finish of procedures mentioned above, three-dimensional model of slope eroded gully was built. At the same time, Trimble TX5 Terrestrial Laser Scanner (TLS) was used to obtain a referential point cloud data of the eroded gully in the experiment. After the preprocessing, point clouds obtained by SFM-MVS technique and terrestrial laser scanner were segmented the same area of gully head and reduced the point number to ten thousand. Comparing reconstructed point cloud with point cloud obtained by terrestrial laser scanner and measured data showed that, dense point cloud generated by photo reconstruction method can completely show the developing form of the gully, especially can achieve a better result in the wall, ridge and rolling area than point cloud obtained by laser scanner. Calculation and analysis showed that average distance between scanned and reconstructed point cloud was 0.0034 m. Respectively generated digital elevation models for two point clouds by Kriging interpolation method, and computing results indicated that the relative error of erosion estimating was 8.054%. Based on the slope map generated by DEM, characteristic lines were extracted, of which the matching rate was 89.592%. The influence of Pixel value on reconstructing process and result was discussed at the end of the paper. The results of the study provided a reference for monitoring gully erosion. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Image processing
Controlled terms:Algorithms - Cameras - Computer vision - Erosion - Image matching - Image segmentation - Interpolation - Landforms - Laser applications - Lasers - Nonlinear programming - Scanning - Stereo image processing - Surveying - Surveying instruments - Water resources
Uncontrolled terms:Hydrology and water resource - Kriging interpolation methods - Nearest neighbor algorithm - Point cloud - RANdom sample and consensus - Scale invariant feature transforms - Scouring experiments - Three-dimensional information
Classification code:405.3 Surveying - 407 Maritime and Port Structures; Rivers and Other Waterways - 444 Water Resources - 481.1 Geology - 483 Soil Mechanics and Foundations - 723 Computer Software, Data Handling and Applications - 741 Light, Optics and Optical Devices - 742.2 Photographic Equipment - 744.1 Lasers, General - 744.9 Laser Applications - 921 Mathematics - 921.6 Numerical Methods - 922 Statistical Methods
DOI:10.3969/j.issn.1002-6819.2015.01.018
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 44>
Accession number:20151000594738
Title:Spatial correlation between vegetation distribution and respirable particulate matter around capital region
Authors:Feng, Zhongke (1); Mao, Haiying (1); Li, Hong (1)
Author affiliation:(1) Beijing Key Laboratory of Precision Forestry, Beijing Forestry University, Beijing, China; (2) Chinese People's Armed Police Force of the Police Academy, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:31
Issue:1
Issue date:January 1, 2015
Publication year:2015
Pages:220-227
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the increasing of the industrialization and urbanization, respirable particulate matter content in the air was increased, which caused serious damages to the surrounding environment of the capital region. In order to reduce the air pollution, analyzing the relationship between respirable particulate matter content in the air and vegetation cover is necessary. This paper researched and analyzed the relationship between respirable particulate matter and vegetation cover according to the region around the central capital, built the capital region with a virtual radius of 100 km for the unit circle and divided the important factors such as vegetation, soil, environment, topography to different scales under rectangular grid. Five-year atmospheric pollutant data from 2008 to 2012 was used in this paper, which was provided by the Beijing Municipal Environmental Protection Bureau. The interpolation method of GS+ software and Moran's index were used to analyze spatial autocorrelation of the above variable factors and to calculate the radius of spatial influence in the capital region. Based on a rectangular grid method and Moran's index method, combined with SPSS software, this paper analyzed the distribution of vegetation and the concentration of respirable particulate matter in the air with the distance between the changes of the relationship. After Moran's index derived vegetation distribution and respirable particulate matter in the region around the capital concluded between the grid scale with increasing autocorrelation reduced. Autocorrelation range of vegetation cover is 6620-7131 m, and respirable particulate matter from the relevant sphere influence is 2 998-6 864 m. The spatial correlation distance between vegetation distribution and respirable particulate matter effect 41.87 km through nonlinear regression analysis with SPSS software, the standard errors(P) are between 0.001-0.003, correlation coefficient R<sup>2</sup> are more than 80%, and therefore non-linear regression model fits better. The accuracy of the model is more than 90%, while all kinds of factors aside 20% of the sample points to the selected model F-test, get outside accord accuracy above 90%. We use the gravitational extended formula to derive spatial correlation of vegetation (vegetation cover, biomass) and environmental factors-respirable particulate matter, the average spatial correlation of rainfall and temperature and calculate distance. The conclusion is drawn that the vegetation influence is decreased followed by the increase of the distance at different side length range and grid value. The innovation of this study is to establish the rectangular grid center in the Beijing Ring, and develop all kinds of elements in equality inside each grid. Each grid center is taken as the center point of the study sample. Through this study, the environmental pollution area is defined in the space radiation radius, which is helpful to remediation for that specific range, such as the introduction of appropriate measures, carrying out the reasonable control lest the car exhaust and factory emissions exceed the environmental capacity, and enhancing public awareness of environmental protection, afforestation according to "suitable tree" principle and in accordance with the rational allocation of species. Environmental effect of central capital region is closely associated with a variety of factors, and this study only establishes the basis of quantitative factors related to model and solves a major factor and the influence radius of various types of qualitative factors; further related research need to be carried in the further. ©, 2015, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Vegetation
Controlled terms:Autocorrelation - Environmental protection - Gases - Gravitation - Linear regression - Pollution - Pollution control - Radiation protection - Reforestation - Regression analysis - Statistics
Uncontrolled terms:Environmental pollutions - Grid - Moran's indices - Non-linear regression analysis - Respirable particulate matters - Spatial autocorrelations - Spatial correlations - Vegetation distribution
Classification code:454.2 Environmental Impact and Protection - 711 Electromagnetic Waves - 744 Lasers - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 921 Mathematics - 922 Statistical Methods - 922.2 Mathematical Statistics - 931.2 Physical Properties of Gases, Liquids and Solids - 931.5 Gravitation, Relativity and String Theory
DOI:10.3969/j.issn.1002-6819.2015.01.030
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
期刊信息
- 主管单位 中国科学技术协会
- 主办单位 中国农业工程学会
- 主编 朱明
- 总编/社长 王应宽
- 地址 北京朝阳区麦子店街41号
- 邮编 100125
- 电话 010－59197078/7077/7076
- 邮箱 tcsae@tcsae.org
微信公众号
二维码
友情链接
- Bioresource Technology
- Industrial Crops and Products
- Biomass & Bioenergy
- Biosystems Engineering
- Aquacultural Engineering
- International Journal of Agricultural and Biological Engineering
- Journal of Irrigation and Drainage Engineering
- Paddy and Water Environment
- Journal of Agricultural Engineering
- Transactions of the ASABE
- Revista Brasileira de Engenharia Agricola e Ambiental
- Applied Engineering in Agriculture
- Engenharia Agricola
- AMA-Agricultural Mechanization in Asia Africa and Latin America
- 中华人民共和国农业农村部-MARA
- 中国科学技术协会CAST
- 国家新闻出版署
- 中华人民共和国科学技术部
- 国家自然科学基金委员会
- U.S. DEPARTMENT OF AGRICULTURE
- CIGR
- ASABE
- EurAgEng-European Society for Agricultural Engineers
- American Society of Agronomy
- Crop Science Society of America
- Soil Science Society of America
- 期刊界
- CNKI
- 万方数据
- 维普