<RECORD 1>
Accession number:20131416161854
Title:Analysis on autonomous task trajectory tracking performance of construction robot with online gravity compensation
Authors:Tang, Xinxing (1); Hou, Jingwei (2); Ni, Tao (2); Zhang, Bangcheng (1)
Author affiliation:(1) School of Mechatronic Engineering, Changchun University of Technology, Changchun 130022, China; (2) College of Mechanical Science and Engineering, Jilin University, Changchun 130025, China
Corresponding author:Tang, X.(petertang1975@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:30-37
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:By the visual feedback and the space position information of the target object of stereo vision camera, the construction robot can realize the autonomous task according to the kinematics analysis and trajectory planning. However, in the process of the autonomous task, because the link mass of construction robot is big, the driving force of the cylinder calculated by the pressure sensors attached at the cylinders will be divided into two parts, one is used for balancing the link gravity, and the other is used for driving the moving of the cylinder. Therefore, the construction robot will overcome the gravity to work in the process of gravity rising along with the lift of boom and swing of arm, and the links gravity of boom and arm will participate in working in the process of gravity fall along with the dropping of boom and swing of arm, this phenomena will influence the moving velocity of construction robot and the effect of the effect of trajectory tracking, especially in the lifting process, moreover, in the process of the links dropping of construction robot, it is dangerous to the construction robot because of the bigger links masses. Aiming at this problem, the dynamics models of construction robot were deduced followed by kinematics analysis, and the least squares method was used for identifying the dynamics parameters, and then online gravity offset method was purposed based on the dynamics parameters, which was used for eliminating the gravity impact from the driving force of the cylinders, and improving the trajectory tracking effect in autonomous task. Finally, experiment was finished on the construction robot test bench, and the experimental results show that the online gravity compensation algorithm could compensate the gravity of construction robot effectively, and eliminate the influence of gravity working to the trajectory planning of construction robot, and the tracking errors under online gravity compensation are smaller than no gravity compensation, therefore, the online gravity compensation will be propitious to reduce the trajectory tracking errors, and improve the trajectory tracking performance of autonomous task, at the same time, the gravity compensation algorithm has important significance to reduce the energy input and consume for the autonomous task of construction robot.
Number of references:26
Main heading:Gravitation
Controlled terms:Algorithms - Construction equipment - Cylinders (shapes) - Dynamics - Experiments - Industrial robots - Kinematics - Least squares approximations - Stereo vision - Trajectories - Visual communication
Uncontrolled terms:Autonomous task - Construction robots - Dynamics parameters - Gravity compensation - Kinematics analysis - Least squares methods - Trajectory Planning - Trajectory tracking errors
Classification code:931.1 Mechanics - 921.6 Numerical Methods - 921 Mathematics - 912.1 Industrial Engineering - 901.3 Engineering Research - 931.5 Gravitation, Relativity and String Theory - 723.5 Computer Applications - 717.1 Optical Communication Systems - 408.2 Structural Members and Shapes - 405.1 Construction Equipment - 404.1 Military Engineering - 723 Computer Software, Data Handling and Applications
DOI:10.3969/j.issn.1002-6819.2013.03.005
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 2>
Accession number:20131416161851
Title:Development of vineyard ditcher with reversal twin rotary tillage wheels
Authors:Ye, Qiang (1); Xie, Fangping (1); Sun, Songlin (1); Yang, Guoshun (2); Yang, Wenmin (1); Li, Zhongkai (1); Liu, Ke (1)
Author affiliation:(1) College of Engineering, Hunan Agriculture University, Changsha 410128, China; (2) College of Horticulture and Landscape, Hunan Agriculture University, Changsha 410128, China; (3) Hunan Provincial Engineering Technology Research Center for Modern Agricultural Equipment, Changsha 410128, China
Corresponding author:Xie, F.(hunanxie2002@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:9-15
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Grapes are a brilliantly colored, tasty, and nutritious fruit popular among consumers. As human dietary preferences change and leisure tourism develops, suburban efficient sightseeing vineyards have attracted more and more attention and will promote grape industry development, increasing the prevalence of large, grape-picking gardens in urban areas. In addition, the grape industry has become an important source of suburban wealth. The cultivation mode of grapes is frame type, and its space is so narrow and low that small orchard-management machinery does not work well. During grape planting and management, plowing and fertilizer application (especially fertilizer injection) are very important processes that have critical influence on grape yield and sugar content. Traditionally, vineyard fertilizer is a manual process with high labor intensity and low work efficiency. To improve production efficiency in fertilizer application, a small fertilizer injector for vineyards was adapted from the design of larger agricultural machines. It works by submerged, reverse rotary tillage. Motor power is divided into two independent gearboxes and drive trains, one drives the rotary tillage wheels, and the other drives the drive wheels. Soil knocks against a retaining plate and is thrown to both sides of the slot created as the rotary tillage wheels' blades cut through the soil. The submerged reverse rotary tillage wheel consists of a homemade curved knife, a homemade wide wing knife, the wheel hub, bar, the cutter holder, and the wheel assembly. Both the homemade curved knife and the homemade wide wing knife are divided into two discs (left and right); the left rotary tillage wheel installed left direction and the right installed right. The radius of the rotary tillage wheels is 300 mm. The distance between the left and right rotary tillage wheels is 250 mm, creating a furrow width of about 250 mm. The knife assembly that installed on each rotary tillage wheel consists of 16 knives which distribute in the hub evenly. The depth of the slot may be controlled by the guide wheel. The angle and opening of retaining plate may be regulated by adjustment device so that soil will be thrown to both sides of the furrow, and not back into the slot. The small clear plough, which was installed in the gearbox, can break balky soil, and that broken soil can be thrown out by rotary tillage wheels' blade. A prototype injector was made and tested for field use. The results showed that the injector could open a furrow at a depth of 500 mm through two-time ditching and a width of 200 mm, which met the agricultural fertilizer requirement of the ditcher for vineyard. The machine can pulverize soil and eject it as well making it suitable for the management of suburban vineyards.
Number of references:21
Main heading:Cultivation
Controlled terms:Agricultural machinery - Design - Experiments - Fertilizers - Fruits - Jet pumps - Soils - Wheels
Uncontrolled terms:Agricultural machine - Cultivation modes - Ditcher - Fertilizer applications - Industry development - Labor intensity - Production efficiency - Rotary tillages
Classification code:901.3 Engineering Research - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 804 Chemical Products Generally - 618.2 Pumps - 601.2 Machine Components - 483.1 Soils and Soil Mechanics - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.03.002
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 3>
Accession number:20131416161853
Title:Modeling and optimizing dither mechanism for conveying corn stubble
Authors:Quan, Longzhe (1); Zhang, Dan (2); Zeng, Baigong (3); Tong, Jin (3); Chen, Donghui (3)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin 150030, China; (2) Heilongjiang Vocational College, Harbin 150080, China; (3) Key Laboratory for Terrain-Machine Bionics Engineering, Ministry of Education, Jilin University, Changchun 130022, China
Corresponding author:Tong, J.(quanlongzhe@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:23-29
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:One kind of agricultural machine was researched to harvest corn stubble. This machine consists of three subsystems: the excavating subsystem consists of a stubble spade and stubble push device; the stubble soil separation subsystem consists of a fist level screening conveyor chain, fixed roll, and second level screening conveyor chain; and the stubble collect and dump subsystem consists of a stubble collector container and dumping device. The screening conveyor chain is very important to the machine, as in the course of conveying corn stubble, the appearance of slipping off, piling up and clogging affected the harvest performance. In order to improve the dither mechanism performance of conveying corn stubble, the method of Combing theory analysis and experiment research was used to optimize the mechanism. Firstly, the dynamic model of corn stubble which is on the jitter chain was established, then the moving up and jumping critical condition of corn stubble were determined; Secondly, according to theoretical model and structural parameters of the whole system, the theoretical optimum parameters were obtained. The tilt angle of the mechanism is 23°, the rotational speed of driving wheel is 120 r/min, and the height of the chain is 34 mm. At last, by means of a test stand of dither mechanism and high-speed photography system, the moving up and jumping course of corn stubble were recorded and analyzed, The test results show that corn stubble can move up with jitter chain collectively, and corn stubble also can jump steadily.
Number of references:24
Main heading:Agricultural machinery
Controlled terms:Conveyors - Dynamics - High speed photography - Jitter - Models - Optimization
Uncontrolled terms:Agricultural machine - Corn stubbles - Critical condition - Experiment research - Optimum parameters - Rotational speed - Structural parameter - Theoretical models
Classification code:931.1 Mechanics - 921.5 Optimization Techniques - 902.1 Engineering Graphics - 821.1 Agricultural Machinery and Equipment - 742.1 Photography - 718 Telephone Systems and Related Technologies; Line Communications - 717 Optical Communication - 716 Telecommunication; Radar, Radio and Television - 692.1 Conveyors
DOI:10.3969/j.issn.1002-6819.2013.03.004
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 4>
Accession number:20131416161865
Title:Relationship between tensile properties and microstructures of three different broadleaf tree roots in North China
Authors:Jiang, Kunyun (1); Chen, Lihua (1); Gai, Xiaogang (1); Yang, Yuanjun (1)
Author affiliation:(1) Key Laboratory of Soil and Water Conservation and Desertification of Education Ministry, College of Water and Soil Conservation, Beijing Forestry University, Beijing 100083, China
Corresponding author:Chen, L.(c_lihua@bjfu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:115-123
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Forest vegetation is known to increase slope stability by reinforcing soil shear resistance, and root tensile properties are important factors to consider when choosing suitable species for reinforcing soil on an unstable slope. The macroscopic properties are determined by the microscopic structure; as a result, the microscopic structure of roots needs to be further observed to help us understand the relationship between the soil's mechanical properties and the microstructure of roots. We chose three common broadleaf species (Betula platyphylla, Quercus mongolica, Ulmus pumila) in North China and carried out several experiments, including single-root tensile tests, root anatomical-structure tests, and wood-fiber segregation experiments. To analyze data from those experiments, we used multiple regression and analysis of variance (ANOVA) in order to determine the relationship between root tensile properties and selected anatomical structure. Results showed that in all species a significant power relationship existed between tensile properties and root diameter (R<sup>2</sup>>0.8). The root tensile force increased with increasing root diameter, but root tensile strength increased with decreasing root diameter. According to the results of root tensile tests, we found that Ulmus pumila was the most resistant to failure, followed by Betula platyphylla and Quercus mongolica. Through the observation of microscopic sections, the root anatomical features of three kinds of broadleaf species were the same as those of their trunk, and wood fiber was the main anatomical feature in the root. According to the multiple regression models, the area percentage of wood fiber in the root cross-section (short for the area percentage of wood fiber), the area percentage of phloem in root cross section (short for the area percentage of phloem), and fiber dimensions affected single roots' tensile properties. The percentage of wood fiber area was the most important impact factor on root tensile force, exhibiting positive correlation. The percentage of phloem area had the biggest influence on root tensile strength. Wood fiber length, the length-width ratio of wood fiber, and the ratio of cell wall to cell cavity also affected tensile properties, but their quantitative influence was less than other factors. Although the area percentage of phloem affected root tensile strength, within a given species there was no significant difference in different root diameter. From the measurement of wood fiber in roots, we found that wood fiber size and type were different in the three selected species. The quantity of wood fiber increased with increasing root diameter, but the size of wood fiber varied only slightly. In three different broadleaf species' roots, the related index (including the percentage of wood fiber area, the percentage of phloem area, and the fiber dimensions) of Ulmus pumila was higher than that of Betula platyphylla and Quercus mongolica in the same diameter; that is to say, Ulmus pumila had better tensile properties than the other species. In accordance with the root anatomical features, fiber dimension, and tensile properties, Ulmus pumila, the roots of which have a better ability to reinforce soil on unstable slopes, is an appropriate broadleaf species for soil and water conservation.
Number of references:28
Main heading:Fibers
Controlled terms:Biomechanics - Experiments - Mechanical properties - Microstructure - Molecular structure - Plants (botany) - Regression analysis - Reinforcement - Slope stability - Soil testing - Soils - Tensile properties - Tensile testing - Water conservation - Wood products
Uncontrolled terms:Broadleaf Plant's roots - Macroscopic properties - Microscopic structures - Multiple regression model - Properties and microstructures - Quantitative influence - Significant differences - Soil and water conservation
Classification code:801.4 Physical Chemistry - 811.2 Wood and Wood Products - 812 Ceramics, Refractories and Glass - 951 Materials Science - 817 Plastics and Other Polymers: Products and Applications - 922.2 Mathematical Statistics - 933 Solid State Physics - 901.3 Engineering Research - 483.1 Soils and Soil Mechanics - 461.9 Biology - 415 Metals, Plastics, Wood and Other Structural Materials - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 422.2 Strength of Building Materials : Test Methods - 444 Water Resources - 461.3 Biomechanics, Bionics and Biomimetics
DOI:10.3969/j.issn.1002-6819.2013.03.016
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 5>
Accession number:20131416161878
Title:Characteristic of nutrients and evaluation of heavy metal contamination on sediments among Xinpo pond, Nandu river in Hainan province
Authors:Liu, Yongbing (1); Jia, Bin (1); Li, Xiang (1); Wu, Jun (2); Meng, Ping (2); Hong, Wenliang (2); Zhao, Congju (3)
Author affiliation:(1) Environmental Protection Research Institute of Light Industry, Beijing Key Lab of Industrial Contamination and Remediation, Beijing 100089, China; (2) Haikou City Major Land Arrangement Project Leading Group Office, Haikou 570312, China; (3) School of Geography and Tourism, Hainan Normal University, Haikou 571158, China
Corresponding author:Zhao, C.(congjuzh@hainnu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:213-224
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Sediment, the major reservoir of contaminants in a lake, contains not only hazardous matter, but also nutrients like nitrogen, phosphorus, and organic matter. So the detoxification, recycling and reuse of sediment has been widely studied. Agricultural land use of sediment is a potentially feasible approach for contaminated site remediation and can achieve good economic and environmental benefits. The key concept is to control the pollutant content and soil burden according to the related environmental standards. Heavy metals reserved in agricultural soil would greatly affect the grain yield and quality, as well as food safety, and are one of the major environmental pollution sources threatening human health. In this article, the sediment content in Xinpo Pond of the Nandu River Valley was planned to be used as the substitute soil of plough horizon in farmland remediation engineering to develop vegetable farming. To investigate the nutrient content and the degree of heavy metal contamination of the pond sediment, the shape and dimension of the pond, characteristics of the cross-section, flow rate, and the amount of sediment were comprehensively explored. Typical cross-section and grid sampling methods were chosen to collect samples within the 0~40 cm depth of the sediment. Based on (a) farmland environmental quality evaluation standards for edible agricultural products as the heavy metals evaluation criteria and (b) the second national soil survey classification criteria as the nutrient evaluation criteria, adopting sample testing, statistical analysis, nutrients gray correlation analysis, Nemerow pollution index assessment and GIS spatial analysis, the nutrient characteristics, soil fertility, heavy metal content, pollution degree and spatial distribution of the pond sediment were analyzed. The results showed: 1) Total nitrogen, total phosphorus, total potassium and organic matter content of the sediment presented spatial heterogeneity. Sediment total nitrogen content was in the range of 0.1300 ~ 6.7600 g/kg with an average of 2.8717 g/kg; total phosphorus content was in the range of 0.1097 to 2.3108 g/kg with a mean of 1.1824 g/kg; total potassium content fell in the range of 2.3000 ~ 16.8000g/kg with a mean of 9.3000 g/kg; and the organic matter content fell in the range of 22.7195 to 167.8769 g/kg with a mean of 92.9408 g/kg. Mean values of total nitrogen and total phosphorus at the lower reach outweighed those at the upper reach by 32.45% and 11.88%, respectively, while total potassium and organic matter content at the lower reach were lower than those at the upper reach by 14.64% and 14.62%, respectively. The variation coefficient of nutrient data from the upper reach sediment were generally higher than those from the lower reach sediment, resulting from the flow rate, ambient natural environment and farming activities. Total nitrogen, total phosphorus, and organic matter reached level 1 (abundant), and the total potassium content was in level 5 (scarce). From evaluation of sediment nutrient based on the analysis of grey correlation, the average fertility indices of Ponds sediment and control processing were 0.4703 and 0.4685, respectively. The nutrients in the sediment were higher than that of the control point, which supported agricultural application of the sediment. 2) The mean contents of Cr, Ni, Cu, Zn, Cd, Pb, As, and Hg in sediments of the study area were 135.5983, 51.0098, 78.5999, 113.3576, 0.4245, 30.5595, 5.3038, and 0.1739 mg/kg, respectively. Heavy metal contamination was mainly attributed to Cd and Cu, followed by Cr and Ni, whose exceeding rates were 76.92%, 47.44%, 56.41%, and 23.07%, respectively; their exceeding magnitudes were 58.45%, 104.58%, 6.06%, and 68.48%. Heavy metal contamination resulted from the fact that the soil parent materials are mafic volcanic rocks, which caused high background values of the metals in the soil. Heavy metals in the soil were flushed by acid rain into the pond through surface runoff. From the Nemerow Index evaluation, the sediment was mainly slightly polluted (46.15% of the samples) to moderately polluted (28.21% of the samples). Contamination of the sediment was also spatially distributed, among which 62.05% of the site was at the slightly contaminated level (level 3) and 25.80% of the site was at the moderately contaminated level (level 4). The watercourse at the lower reach was wider and the flow rate was slow, increasing the rate of sediment deposition, the deterioration of sediment contamination, and the heterogeneity of spatial distribution. Therefore, the patterns of agricultural land use should be critically determined according to the contamination levels and nutrient conditions of the sediment.
Number of references:33
Main heading:Sediments
Controlled terms:Acid rain - Agricultural products - Biogeochemistry - Biological materials - Contamination - Detoxification - Farms - Flow rate - Forestry - Heavy metals - Lakes - Land reclamation - Lead - Nickel - Nutrients - Organic compounds - Pollution - Potassium - Reservoirs (water) - River pollution - Sedimentology - Soil surveys - Soils - Spatial distribution - Standards
Uncontrolled terms:Classification criterion - Economic and environmental benefits - Environmental pollutions - Environmental standards - Gray correlation analysis - Heavy metal contamination - Organic matter content - Sediment contamination
Classification code:531 Metallurgy and Metallography - 546.1 Lead and Alloys - 548.1 Nickel - 549.1 Alkali Metals - 483.1 Soils and Soil Mechanics - 631 Fluid Flow - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.2 Codes and Standards - 921 Mathematics - 804.1 Organic Compounds - 483 Soil Mechanics and Foundations - 441.2 Reservoirs - 442.2 Land Reclamation - 451.1 Air Pollution Sources - 453 Water Pollution - 407 Maritime and Port Structures; Rivers and Other Waterways - 454.2 Environmental Impact and Protection - 461 Bioengineering and Biology - 481.1 Geology - 481.2 Geochemistry - 454.3 Ecology and Ecosystems
DOI:10.3969/j.issn.1002-6819.2013.03.029
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 6>
Accession number:20131416161873
Title:Energy saving effect on cooperating cooling of conditioner and air exchanger in plant factory with artificial light
Authors:Wang, Jun (1); Yang, Qichang (1); Wei, Lingling (1); Tong, Yuxin (1)
Author affiliation:(1) Institute of Environment and Sustainable in Agriculture, Chinese Academy of Agricultural Science, Beijing 100081, China; (2) Key Laboratory for Energy Saving and Waste Disposal of Protected Agriculture, Ministry of Agriculture, Beijing 100081, China
Corresponding author:Yang, Q.(yangq@ieda.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:177-183
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In recent years, the use of plant factory with artificial light (PF) for plant production is gradually increasing in many countries due to its incomparable advantages compared with other plant production systems, such as improving the utilization efficiencies of water and land, improving work conditions. However, the higher initial construction and operation costs limit the further use of the PF. The main electric-energy consumption by air conditioner (AC) for cooling accounts for 15%-25% of the total energy consumption in the PF. In this experiment, the objective of this study is to reduce the electric-energy consumption for cooling in the PF. The air temperature inside the two PFs (floor area: 10.5 m<sup>2</sup>) was maintained at 25°C and 15°C during photoperiod and dark period, respectively. In one PF, an air exchanger (AE, air quantity: 250 m<sup>3</sup>/h) was used along with an AC to maintain the inside air temperature at the set-point. The air exchanger was used to exchange the air inside with that outside when the air temperature outside was lower than a certain degree. When the inside air temperature could not maintained at the set-point, the AC would start. In another PF only an AC was used. The results showed that the electric-energy consumption in the PF with AE reduced by 24.6%~63.0% and 2.3%~33.6% when the outside air temperature ranged from -4°C to 12°C, and the runtime of air conditioner reduced by 36.6%~82.0% and 16.3%~64.2% when the outside air temperature ranged from -4°C to 6°C, during photoperiod and dark period, respectively, compared with the electric-energy consumption in the PF only with AC. And the reduction rates of electric consumption and the runtime of air conditioner increased with the decrease of the air temperature outside. Moreover, the air temperature inside the PF with AE could be maintained at the set-point. The above results indicate that the electric-energy consumption for cooling can be reduced by using the AE compared with the AC. Thus, the use of AE in the PF will be an effective way to reduce electric-energy consumption for cooling and the operation cost.
Number of references:31
Main heading:Atmospheric temperature
Controlled terms:Air conditioning - Cooling - Domestic appliances - Energy conservation - Energy utilization - Operating costs
Uncontrolled terms:Air temperature - Artificial light - Electric consumption - Energy-saving effect - Outside-air temperature - Plant production - Total energy consumption - Utilization efficiency
Classification code:715 Electronic Equipment, General Purpose and Industrial - 643.3 Air Conditioning - 641.2 Heat Transfer - 911.1 Cost Accounting - 525.3 Energy Utilization - 522 Gas Fuels - 443.1 Atmospheric Properties - 525.2 Energy Conservation
DOI:10.3969/j.issn.1002-6819.2013.03.024
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 7>
Accession number:20131416161880
Title:Study on baseline vegetation coverage of desertification grassland in northern sand-fixing region based on remote sensing
Authors:Liu, Tonghai (1); Wu, Xinhong (2); Lü, Shihai (3); Yang, Tingting (2); Zhao, Xinhai (1); Li, Peng (2); Ye, Shengxing (3)
Author affiliation:(1) Department of Computer Science and Information Engineering, Tianjin Agricultural University, Tianjin 300384, China; (2) Grassland Research Institute, China Academy of Agricultural Sciences, Hohhot 010010, China; (3) State Environment Protection Key Laboratory of Regional Eco-process and Function Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China
Corresponding author:Wu, X.(wxh1@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:235-241
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:To promote ecology healthy, safe and steady development of sand-fixing ecological functional zone in northern China, and make the appropriate utilization of grassland resources with balanced and sustainable development, we take Zhenglan Banner as a typical instance of sand-fixing ecological functional zone in northern China to carry out research on baseline vegetation coverage of grassland. By using SPSS, the vegetation coverage remote sensing inversion model is established with normalized difference vegetation index (NDVI) extracted from Landsat TM images and plenty of synchronous field survey data. We use this model to extract the regional vegetation coverage of Zhenglan Banner, distinguish sand lands according to its criteria. With help of ArcGIS and ENVI, we extract spatial distribution data of half fixed sand land and fixed sand land respectively, and then convert data of half fixed sand-land and fixed sand-land to their distribution border polygon vector data. we obtain borderline of half fixed sand land and fixed sand land with polygon transformation tools provided by ArcGIS, and obtain line of intersection of half fixed and fixed sand land with intersection tools. With line of intersection and data of vegetation coverage distribution, we use statistical tools in ArcGIS to extract vegetation coverage corresponding to intersection line and count number of pixels of coverage. We obtain average of vegetation coverage from borderline between semi-fixed sandy land and fixed sandy land with their vegetation coverage and the corresponding number of pixel, and the average coverage of intersection line between two kinds of sandy land is taken as baseline coverage. With the baseline coverage, we regard sandy land which is less than value of baseline as substandard region, only those regions above baseline can be utilized appropriately. Experimental results show that average coverage of intergradation region between semi-fixed sandy land and fixed sandy land is 30.47%, which is verified with baseline coverage field survey. The vegetation coverage remote sensing inversion model C=128.165 × NDVI 20.212 was established with normalized difference vegetation index (NDVI) extracted from Landsat TM images and plenty of synchronous field survey data. Using this model, we extracted vegetation coverage of Zhenglan Banner. And then, the baseline coverage value was gained based on the boundary of the half fixed sand and fixed sand. The baseline coverage was set as the limited value, therefore, we can calculate the area of conservative grazing zone, that is 396, 927.3 hectares, which is 39% of the grassland area in Zhenglan Banner. With data obtained in the experiments, structure of grassland resources utilization was constructed under constraint of ecological protection, which can provide a technical guarantee for promotion of well-balanced circulation of sand-fixing ecosystem, maintain service functions in region ecosystem and appropriately utilize region ecological resources in the north of China.
Number of references:28
Main heading:Vegetation
Controlled terms:Climatology - Data handling - Ecology - Ecosystems - Image processing - Linear transformations - Pixels - Remote sensing - Sand - Statistical mechanics - Surveys
Uncontrolled terms:Baseline coverage - Ecological protection - Ecological resources - NDVI - Normalized difference vegetation index - Transformation tools - Type of sand land - Vegetation coverage
Classification code:921.3 Mathematical Transformations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 731.1 Control Systems - 723.5 Computer Applications - 931.1 Mechanics - 723.2 Data Processing and Image Processing - 454.3 Ecology and Ecosystems - 443 Meteorology - 405.3 Surveying - 505 Mines and Mining, Nonmetallic
DOI:10.3969/j.issn.1002-6819.2013.03.031
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 8>
Accession number:20131416161884
Title:Research on hot-air drying and control model for dry basis moisture content of seed cotton
Authors:Wang, Haopeng (1); Feng, Xianying (1); Li, Li (1)
Author affiliation:(1) Key Laboratory of High Efficiency and Clean Mechanical Manufacture, Ministry of Education, Shandong University, Jinan 250061, China; (2) Department of Computer, Shandong Economic Management Institute, Jinan 250014, China
Corresponding author:Feng, X.(fxying@sdu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:265-272
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The initial moisture content (dry basis) of seed cotton picked by machine is very high, occasionally exceeding 18%. However, research has shown that the moisture content between 6.5% and 8.5% is optimal for processing seed cotton. To obtain a higher drying efficiency and better drying quality of seed cotton before cleaning and ginning, it is necessary to control drying conditions within a narrow range. However, many cotton gins currently set and control the temperature of seed-cotton drying equipment based on personal judgments, which is inaccurate and risky. Based on a large number of experiments on hot air drying characteristics, this paper developed a hot-air drying model of seed cotton and solved the above problem. We used quadratic regression in a 3×3 factorial experimental design to model the effects on the final moisture content of three factors (hot air temperature, seed cotton feed rates and initial moisture content) and three levels of each factor. Results show that all three factors significantly influence the drying rate of seed cotton. In addition, the first 15 s of the drying process exhibits a faster drying rate, after which the drying rate rapidly decreases. Curve fitting with a monomial diffusion model, Page's drying model, and a quadratic polynomial model, we found that the monomial diffusion model fit the data more closely (R<sup>2</sup>=0.9549) than the other models. Analyzing the drying process more closely, we determined that our hot-air drying model of seed cotton could provide a theoretical basis for adjusting the control parameters in real time on the drying equipment. Of the three control parameters tested, the final moisture content of seed cotton is most sensitive to (a) the initial moisture content, (b) cotton feed rate, and (c) hot-air temperature, in decreasing order of sensitivity. The hot-air drying model developed in this paper has been applied in real-time control of seed cotton drying in actual production, confirming its utility in process effectiveness and consistency, energy efficiency, and net economic benefit to the ginner.
Number of references:20
Main heading:Drying
Controlled terms:Agricultural products - Atmospheric temperature - Cotton - Curve fitting - Energy efficiency - Food technology - Models - Moisture determination - Quality control - Real time control - Seed
Uncontrolled terms:Factorial experimental design - Final moisture content - Hot air drying - Hot air temperature - Initial Moisture Content - Quadratic polynomial - Quadratic regression - Seed cotton
Classification code:944.2 Moisture Measurements - 921.6 Numerical Methods - 913.3 Quality Assurance and Control - 902.1 Engineering Graphics - 822 Food Technology - 821.4 Agricultural Products - 732 Control Devices - 731 Automatic Control Principles and Applications - 642.1 Process Heating - 525.2 Energy Conservation - 443.1 Atmospheric Properties
DOI:10.3969/j.issn.1002-6819.2013.03.035
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 9>
Accession number:20131416161869
Title:Spatial and temporal changes of multiple cropping index in 1995-2010 in Taihu Lake basin, China
Authors:Xu, Xibao (1); Yang, Guishan (1)
Author affiliation:(1) State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 21008, China
Corresponding author:Xu, X.(xbxu@niglas.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:148-155
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The smooth crops growth NDVI curves from 1995-2010 were rebuilt by the HANTS method of Fourier transform techniques, with the combination of 1 km 10 d NOAA-AVHRR time-series NDVI data in 1995 with the resolution of 1 km, 16 d MODIS time-series NDVI data from 2000 to 2010 with the resolution of 250 m, and land use data in 1995, 2000, 2005 and 2010. Spatial and temporal changes of multiple cropping index in 1995-2010 in Taihu Lake basin were extracted by a difference algorithm, and its pattern was analyzed. The results showed that spatial and temporal pattern of multiple cropping index from 1995 to 2010 in Taihu Lake basin was dominated with the double cropping system, while the proportion for the single cropping system was at the increasing trend. Local changes for multiple cropping index with decreasing or increasing trend mainly concentrated in Shanghai Municipality and Zhejiang province. Spatial pattern of multiple cropping index in Taihu Lake basin presented downward trend from north to south, and average multiple cropping index was generally at the obviously decreasing trend, decreasing from 189.4% in 1995 to 167.3% in 2010. The decreasing extent of multiple cropping index from 1995 to 2010 at the county-level for Zhejiang province and Shanghai Municipality was larger than that in Jiangsu province. The combination of the HANTS method and long time-series NDVI remote sensing data to extract multiple cropping index in Taihu Lake basin has high accuracy with 94.6% at the grid scale. Due to the differences in calculation categories and spatial resolution of remote sensing data, the error between the multiple cropping index extracted by the remote sensing method and the statistics at the county-level ranged from 15.8% to 21.6%. The results can provide a scientific basis for policy-making and management of agriculture in Taihu Lake basin.
Number of references:22
Main heading:Remote sensing
Controlled terms:Error statistics - Land use
Uncontrolled terms:Difference algorithms - HANTS - Multiple cropping index - Remote sensing data - Spatial and temporal changes - Spatial and temporal patterns - Spatial resolution - Taihu Lake basin
Classification code:403 Urban and Regional Planning and Development - 731.1 Control Systems - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2013.03.020
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 10>
Accession number:20131416161870
Title:Remote automatic identification system of field pests based on computer vision
Authors:Han, Ruizhen (1); He, Yong (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China; (2) College of Electronic Information, Zhejiang University of Media and Communications, Hangzhou 310018, China; (3) Cyrus Tang Center for Sensor Materials and Applications, Zhejiang University, Hangzhou 310058, China
Corresponding author:He, Y.(yhe@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:156-162
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to achieve fast real-time identification and diagnosis of field pests, a remote automatic pest identification system was designed in this paper. This system is composed of remote classification platform (ROCP) including personal computer, CMOS camera and 3G wireless communication module and a host control platform (HCP). The ROCP sends the image data, which is encoded using JPEG 2000, to the HCP through the 3G network. The image transmission and communication are accomplished using 3G technology. The system transmits the data via a commercial base station. The system can work properly based on the effective coverage of base stations, no matter the distance from the ROCP to the HCP. The image data was decoded firstly, then the pest was segmented from background, and the morphology features and color features were extracted at last for classification. Sixteen morphology features consisted of perimeter, area, eccentricity and seven Hu invariant moments etc. Nine color features were described by color moments. The support vector machine classifier was used at last for identification. Six species of common field pests including Cnaphalocrocis medinalis Guenee, Chilo suppressalis, Sesamia inferens, Naranga aenesc, Anomala corpulenta Motschulsky, Prodenia litura were tested in the system and the average accuracy is 87.4%. Considering the different pests' pose and different field lighting conditions, the result is satisfactory. The study of the automatic pest identification system which combined with machine vision, image processing, pattern recognition technology and 3G wireless communication technology, was not reported in China. The designed system can automatically identify the field pests and can provide timely and accurate information for pest prevention. The application of the designed system can reduce prevention cost and improve the control effect. The study can provide a reference for agricultural pest prevention.
Number of references:25
Main heading:Base stations
Controlled terms:3G mobile communication systems - Agricultural machinery - Automation - CMOS integrated circuits - Color - Computer vision - Identification (control systems) - Image processing - Monitoring - Morphology - Personal computers - Wireless telecommunication systems
Uncontrolled terms:3G wireless communications - Automatic identification system - Crop protection - Field pests - Hu invariant moments - Pattern recognition technologies - Real-time identification - Support vector machine classifiers
Classification code:951 Materials Science - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 821.1 Agricultural Machinery and Equipment - 741 Light, Optics and Optical Devices - 732 Control Devices - 731 Automatic Control Principles and Applications - 722.4 Digital Computers and Systems - 716.3 Radio Systems and Equipment - 716 Telecommunication; Radar, Radio and Television - 714.2 Semiconductor Devices and Integrated Circuits
DOI:10.3969/j.issn.1002-6819.2013.03.021
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 11>
Accession number:20131416161867
Title:Design and implementation of business management system for crop remote sensing monitoring
Authors:Guo, Lin (1); Wang, Fei (1); Zhang, Yin (1); Pei, Zhiyuan (1); Chang, Jun (2); Tang, Hai (2)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing 100125, China; (2) Beijing Jinhe Tiancheng Technology Company Limited, Beijing 100083, China
Corresponding author:Guo, L.(guo_guolin@sohu.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:132-138
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:With continuous extension of crop remote sensing business and the needs for improvement of agricultural production and management of remote sensing monitoring, business operation and management efficiency has increasingly become a prominent issue. Based on systematic analysis and adjustment of the crop remote sensing monitoring business management process, the Crop Remote Sensing Business Management System (CRSBMS) was designed and implemented. By using Geographic Information System (GIS), database and network technology, the scientific database system was designed to improve the service system capacity and the complete business process of crop remote sensing was implemented, including image data storage management, query, task distribution, reporting, audit and archiving. The business tracking management mechanism was established to make crop monitoring business process standardization and to improve the operation and management efficiency. Based on systematic analysis, CRSBMS was designed as a four-part, image library management system: data transmission system, business tracking system and a one-stop portal. Image library management system is for managing the business involved in the procurement and archiving massive remote sensing image data. Data transmission system is for image data sharing and distribution between business organizational unit and business commitment unit. Business tracking system is designed for providing a visual business process tracking process, with real-time project progress intuitive presented. One-stop portal provide users with intuitive project overall briefing, describing the name of the project and their respective business units, the task is completed the case, the image data downloads. CRSBMS was designed using the hybrid structure of the C/S and B/S, in order to meet the system integration, stability, security, and ease of maintenance needs. Database development used Oracle 11g as a unified database platform. Client applications access the database through ArcSDE, server-side support for multi-user access. Version1.0 of CRSBMS was released in January 2011. We carried out a preliminary application in Agriculture crop monitoring business of Remote Sensing Applications Center of the Ministry. Results showed that CRSBMS basically has achieved the expected design goals: 1) Completed crop monitoring business workflow and business-critical node, real-time, fully reflected the progress of the business, simplify data sharing processes, and improved the business management efficiency. 2) The Database of CRSBMS, designed scientifically, could manage massive spatial data effectively, reduce the system response time of concurrent requests in significantly and enhance carrying capacity of business system capacity. 3) Based on existing business processes, the system is lacking in flexibility. CRSBMS could be more flexible process customization based on business needs change in future, users could choose appropriate business processes and management models depending on different needs. 4) To improve system security, further research is needed in the system encryption algorithms, hardware encryption devices and remote disaster recovery.
Number of references:24
Main heading:Information management
Controlled terms:Crops - Cryptography - Database systems - Efficiency - Geographic information systems - Image reconstruction - Information theory - Management information systems - Modems - Monitoring - Query processing - Remote sensing - Search engines - Telecommunication equipment
Uncontrolled terms:Agricultural productions - Business management - Business management process - Business management systems - Design and implementations - Operation and management - Remote sensing applications - Remote sensing monitoring
Classification code:821.4 Agricultural Products - 903.2 Information Dissemination - 913.1 Production Engineering - 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 - 741 Light, Optics and Optical Devices - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 718.1 Telephone Systems and Equipment - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems
DOI:10.3969/j.issn.1002-6819.2013.03.018
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 12>
Accession number:20131416161881
Title:Evaluation of spatial distribution of basic farmland conservation area in Yinchuan
Authors:Li, Jianchun (1); Zhang, Junlian (1); Li, Xianwen (2); Su, Dongxi (2)
Author affiliation:(1) Key Laboratory of Agricultural Land Quality and Monitoring, College of Resource and Environment, China Agricultural University, Beijing 100193, China; (2) China Institution of Land Surveying and Planning, Beijing 100035, China
Corresponding author:Zhang, J.(junlian@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:242-249
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Basic farmland area determined by overall land use planning in China, is regarded as important measures to guarantee the grain quantity and food security. The quantity of basic farmland is strictly restrained by the government, but the quality relate to the location is not well supervised. Thus, with land reclamation planning and high-standard basic farmland project, it is of importance to evaluate the spacial allocation of basic farmland for raising the quality of basic farmland. We pick Yinchuan as study area, which is a rapid development city in the west of China. There are many contradictions between economic development and protection of farmland in recent years. Firstly, according to the requirement of basic farmland delineation, we construct a methodology consisting of suitability and coordination, which represents the impact of natural conditions and land-use system of basic farmland protection areas. Secondly, we choose various index based on the local situation. The suitability index contains slope, soil texture, river system distance, and degree of soil salinization. The coordination index contains the distance to the center town, polygon area, the proportion of arable land, and proportion of overlapping planning zone. The weight of each index is determined by the Delphi method with relevant reference information as well as provincial experienced experts. Besides, with the help of ArcGIS9.3, we use Comprehensive Fitness Evaluation Model and Experience Index Method to calculate and drawing the suitability classification map and land-use system coordination classification map. Lastly, we use GIS spatial analysis to superimpose two classification maps, and mutually exclusive matrix classification is used to integrate these two reciprocally independent indicators. The result shows that, the basic farmland is divided into five different types according to the classification matrix: I. Completely rational zone; II. Basic rational zone; III. Development reserve zone; IV. Reduction zone and V. Unreasonable zone. The rational region (I, II and III types) accounted for 90.76% of total basic farmland protection area in Yinchuan, which means that the current planning scheme is basically rational. Unreasonable regional area (IV and V types) accounted for 9.24%, which mainly distribute in the edge of basic farmland concentration area, with patchy distribution. These districts are influenced by two aspects of the suitability and coordination. It is suggested that delineating basic farmland area does not only mean selecting high quality arable land by technical, but also focusing on the influence of the coordination between the various factors of the land use system. This study provides a new way of evaluating basic farmland's spatial layout, points out the techniques and methods, and shows specific evaluation and decision-making process. The innovation of this paper is that: 1) Establishing evaluation index of system coordination; 2) Applying mutually exclusive categories to integrating natural conditions and system coordination; 3) By selecting Yinchuan city as study area, demonstrating the problems in basic farmland protection areas delineated in western regions of China.
Number of references:31
Main heading:Farms
Controlled terms:Conservation - Economics - Food supply - Geographic information systems - Land reclamation - Land use - Quality control
Uncontrolled terms:Basic farmland protection areas - Classification matrix - Decision making process - Evaluation - Farmland conservation - Measures - Spatial layout - Yinchuan
Classification code:971 Social Sciences - 913.3 Quality Assurance and Control - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 723.3 Database Systems - 454 Environmental Engineering - 442.2 Land Reclamation - 404.2 Civil Defense
DOI:10.3969/j.issn.1002-6819.2013.03.032
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 13>
Accession number:20131416161862
Title:Development and experiment of handheld digitalized and multi-functional forest measurement gun
Authors:Xu, Weiheng (1); Feng, Zhongke (1); Su, Zhifang (3); Xu, Hui (2); Jiao, Youquan (1); Fan, Jiangchuan (1)
Author affiliation:(1) Institute of GIS, RS and GPS, Beijing Forestry University, Beijing 100083, China; (2) Computer and Information Institute, Southwest Forestry University, Kunming 650224, China; (3) Department of Mathematics, Kunming University, Kunming 650214, China
Corresponding author:Feng, Z.(fengzhongke@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:90-99
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Forest mensuration is one of the basics in forestry science and the related fields. In this paper, a new handheld digitalized and multi-functional electronic forest measurement gun was designed and implemented to achieve digitalization, multi-function and precise mensuration in forest field inventory. Used to measure distance, angle of inclination and magnetic azimuth, the instrument was built upon such hardware as MEMS (Micro-Electro-Mechanical Systems) angle measurement sensor, and distance measurement laser sensor, MCU (Micro Controller Unit), flash memory, LED (Liquid Crystal Display), micro button, and USB (Universal Serial Bus). The instrument, based on the trigonometric principle, and operational software embedded, helped to achieve six functions in terms of individual tree height measurement, stand height measurement, stand density measurement, angle gauge, diameter and corresponding height at free position measurement, and basic measurement. To validate these six functions, a series of experiments were conducted respectively in 30 sample areas in Henan Province and 20 sample areas in Inner Mongolia, China. Data analysis and comparison demonstrated the following findings. In terms of tree height measurement, the measurements deviation of the electronic forest measurement gun and the total station was between 0.2%-1.6%, with an average accuracy of 99.39%. The relative error of angle gauge mounted on the electronic forest measurement gun and the lever-type angle gauge (Type: wi70448) was 4.75%, with the average accuracy of 95.25%. The relative error of stand mean height measured by electronic forest measurement gun and by average sample tree determination method was 5.03%, with the average accuracy of 94.97%. Compared with the conventional manual measurement approach, the relative error of numbers per unit area measurement function was 3.89%, with the average accuracy of 96.11%. When the forest measurement gun was used to measure diameter and corresponding height at free position, the relative error of diameter measurement between the forest measurement gun and tape was 4.42%. The relative error of corresponding height measurements between the electronic forest measurement gun and the total station was 1.25%, and the results correspond well with forest measurements. Regarding basic measurement functions, the average error of inclination measurement was 8'24″ and the average error of slope distance measurement was 5.56 mm relative to total station. The average error of azimuth measurement was 27'36″ relative to the angle scale. of all the functions, the accuracy of stand height was the lowest, 94.97%, while the accuracy of other functions was all above 95%. The results indicate that the instrument is able to meet the requirements of forestry field inventory and planning.
Number of references:30
Main heading:Forestry
Controlled terms:Electron guns - Experiments - Flash memory - Gages - Liquid crystal displays - Measurements - MEMS - Sensors - Standards - Timber
Uncontrolled terms:Determination methods - Diameter Measurement - Measurement function - Micro controller units - Micro electro mechanical system - Multi-functions - Operational software - Tree height measurements
Classification code:944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 901.3 Engineering Research - 902.2 Codes and Standards - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 943.3 Special Purpose Instruments - 821.0 Woodlands and Forestry - 722.2 Computer Peripheral Equipment - 722.1 Data Storage, Equipment and Techniques - 714.1 Electron Tubes - 704.2 Electric Equipment - 415.3 Wood Structural Materials - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2013.03.013
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 14>
Accession number:20131416161876
Title:Screening of bioflocculant-producing strains and optimization of its nutritional conditions by using potato starch wastewater
Authors:Yan, Dongfang (1); Yun, Jianmin (1)
Author affiliation:(1) College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, 730070, China
Corresponding author:Yun, J.(yunjianmin@gsau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:198-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In recent years, researchers have paid more and more attention to bioflocculants in waste disposal study. Because the bioflocculants were usually biodegradable and their degradation products were harmless to environment, so the bioflocculants have a good application prospects. However, it was not widely used to practical application till now, because of its low flocculation ability of producing strain and high cost. One measure to decrease the cost associated with the production on industrial scale was to employ low-cost substrates. To develop a novel bioflocculant, a novel technology of producing bioflocculant was studied through screening biofloccuant-producing microorganism which could utilize potato starch wastewater as substrate, then its nutritional conditions was optimized. Moreover, the study would provide a new way for potato starch wastewater reutilization. In the study, 100 strains were isolated from activated sludge. Each strain was cultured separately in either nutrient agar or potato dextrose agar as primarily screening flocculant-producing strain medium. The flocculation rate of fermentation broth against Kaolin clay suspension was used as the evaluation index, 13 bioflocculant-producing strains were screened. According to the ability of strains fermenting potato starch wastewater and producing flocculants, one high yield strain was obtained, named as F5, which was identified as Candida anglica by 26SrDNA analysis. The nutritional contditons that C. anglica fermented potato starch wastewater to produce bioflocculant were optimized through single factor test and the orthogonal test. The results showed that under the conditions of pH value 5.6, inoculum size 10%( volume fraction), 150 r/min and 28°C for 48 h, the best nutritional compositions were: 1 mL/100 mL glycerin as adding carbon sources, 0.05 g/100 mL (NH<inf>4</inf>)<inf>2</inf>SO<inf>4</inf> as nitrogen source, 0.1 g/100 mL MgCl<inf>2</inf> and 0.1 g/100 mL KH<inf>2</inf>PO<inf>4</inf>. The test showed that C. anglica could grow well in non-sterilization potato starch wastewater as basic substrate, and could accumulate flocculation active substance effectively. At that time, the flocculation rate of fermentation broth against Kaolin clay suspension was 94.6%, the COD<inf>Cr</inf> removal rate of potato starch wastewater was 93.7%, and the yield of bioflocculant was 1.36 g/L. It indicated that C. anglica would be a new strain for producing bioflocculants. The results could provide a reference for potato starch wastewater treatment and biological reuse.
Number of references:32
Main heading:Strain
Controlled terms:Algae - Clay - Costs - Degradation - Fermentation - Flocculation - Kaolin - Optimization - Starch - Substrates - Suspended sediments - Suspensions (fluids) - Waste disposal - Wastewater treatment
Uncontrolled terms:Application prospect - Bioflocculants - Degradation products - Fermentation broths - Flocculation rate - Nutritional compositions - Nutritional conditions - Potato dextrose agars
Classification code:802.2 Chemical Reactions - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 911 Cost and Value Engineering; Industrial Economics - 921.5 Optimization Techniques - 951 Materials Science - 801 Chemistry - 421 Strength of Building Materials; Mechanical Properties - 452.4 Industrial Wastes Treatment and Disposal - 461 Bioengineering and Biology - 461.2 Biological Materials and Tissue Engineering - 482.2 Minerals - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics
DOI:10.3969/j.issn.1002-6819.2013.03.027
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 15>
Accession number:20131416161887
Title:Construction of mathematical model for heat and mass transfer of Chinese cooking
Authors:Deng, Li (1)
Author affiliation:(1) Life Science College, GuiZhou University, Guiyang 550025, China
Corresponding author:Deng, L.(denglifood@foxmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:285-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:There has been great development of the food industry and the food preparation equipment industry, and automatic food preparation equipment has come into service. Although research on the principles of the cooking process can explain the advantages and rationality of traditional cooking skills, the more important significance of it is to reveal the principle of cooking quality formation, to find out key control parameters, and to provide a theoretical and practical foundation for automatic cooking. Currently, most Chinese cuisine literature associated with heat transfer is qualitative and vague. In reality, heat transfer plays a crucial role in the quality of the finished product in traditional Chinese cuisine, therefore it is necessary to study the heat transfer of the cooking process in order to reveal the core principle of Chinese cooking. The complicated operation of Chinese cooking were divided into three types: raw material compatibility, cutting controlling and heating controlling, by the author, and it was related to such as the principle of process transport, reaction kinetics, food chemistry, food physical, food microbiology. Thus, process transport-reaction kinetics-food quality change was considered the core principle of Chinese cooking. After a discussion of traditional materials, the related chemical reaction, heat transfer, mass transfer, momentum transfer and reactor for Chinese cuisine, it was considered that heat transfer, mass transfer, relative motion and quality changes of the fluid-particulate system in the open container is characteristic of Chinese cooking. The typical Chinese cooking process is to mix a liquid and particulates with stirring and heating in a vessel open to the atmosphere, where the heat flux direction is from the heating source to the vessel to the liquid to the particles, and includes intraparticle heat conduction from the surface to the center. The heat transfer of Chinese cooking covers all of conduction, convection and radiation. The transient governing equations of the cooking vessel are established depending on the thermal balance, with the boundary conditions of convection and radiation on the outer wall with a combusting gas, and convective heating on the inner wall with liquid, and losing heat via radiation on the exposed outer wall. When the evaporation of particulates don't exist, based on the thermal balance of liquid and particulates, the transient governing equations of intraparticle heat conduction are given with the boundary condition of convection between liquid and particulates. When the evaporation of particulates exists, the governing equations of heat and mass transfer for particulate are given based on the porous media theory, and water, oil, steam and air are considered as the mobile phase. Thus, the complete mathematical model of the Chinese cooking transfer process was put forward. The discussion showed that the mathematical model is well representative, and can be used to describe most Chinese cooking processes directly. The mathematical model has high reliability, because it consists of a theoretical basis and a semi-rational formula with rigour assumptions. This mathematical model can be applied to most cooking processes to explain transport phenomena and analyze controlling parameters and optimize the conditions of the cooking process. The characteristics of the transport process were discussed preliminarily for Chinese cuisine. Via analyzing the thermal resistance from heating source to vessel to liquid to particles in the cuisine, the convection heat transfer of vessel-liquid and liquid-particles, together with thermal conduction, was found to play a dominant role in general heat transfer, and these three have a significant influence on the cooking process. Due to manual stirring, the convection heat transfer in a vessel between liquid-vessel and liquid-particulates is unstable, and shows sophistication, however, the surface heat exchange coefficients of liquid-vessel are close to those of liquid-particulates. Thus, preheating oil is necessary in traditional Chinese cooking to improve the heating rate of the particulates. Research has shown that the heating of food particles has significant unsteady characteristics under the condition of Chinese cuisine.
Number of references:35
Main heading:Oils and fats
Controlled terms:Association reactions - Boundary conditions - Evaporation - Food processing - Heat conduction - Heat convection - Heat flux - Heat radiation - Heating - Heating equipment - Liquids - Mass transfer - Mathematical models - Phase transitions - Porous materials - Reaction kinetics - Temperature
Uncontrolled terms:Chinese cuisine - Controlling parameters - Governing equations - Heat and mass transfer - Heat exchange coefficients - Transient governing equations - Transport process - Unsteady characteristics
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 921 Mathematics - 822.3 Food Products - 822.2 Food Processing Operations - 951 Materials Science - 802.3 Chemical Operations - 643.1 Space Heating - 642.2 Industrial Furnaces and Components - 641 Heat and Mass Transfer; Thermodynamics - 802.2 Chemical Reactions
DOI:10.3969/j.issn.1002-6819.2013.03.038
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 16>
Accession number:20131416161882
Title:Structure optimization and performance simulation of screw discontinuous feeding device
Authors:Luo, Sheng (1); Zhang, Xiliang (1); Xu, Jun (1); Ma, Kui (1)
Author affiliation:(1) School of Mechanical Engineering, Jiangsu University, Zhenjiang, 212013, China
Corresponding author:Zhang, X.(zhangxl@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:250-257
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Discontinuous, quantitative materials feeding is an important process in industrial and agricultural production. Adapting a spiral feeding device to operate in a discontinuous mode has many advantages, such as good sealing properties, high energy efficiency, simple structure, more effective and better control. Compared with the traditional discrete- quantitative design, converting a spiral feeding device to achieve discontinuous quantitative feeding can shift the quantitative method from passive measuring feeding to active quantitative feeding. It also omits the weight measuring procedure, so as to improve the process-monitoring efficiency with a broad prospect of application. To deal with the instability of materials feed rates and the high-energy consumption of discontinuous spiral feeding device, structure optimization and performance simulation were studied in this paper. The performance index of spiral feeding and the different structural parameters' effects on discontinuous feeding performance were analyzed firstly. Moreover, with the spiral discontinuous feeding device of 100 mm outer diameter as the research subject, minimizing the energy consumption per unit of feeding amount as the optimization goal, the inner diameter, the pitch, and the operating speed were chosen as optimization variables. On the basis of certain constraints, a stochastic direction method was used to acquire the optimization results: speed of 65 r/min, inner diameter of 40 mm, and thread pitch of 85 mm. Furthermore, the discrete element method was used to simulate the effect of changing the inner diameter and pitch on feeding performance, such as particle filling rate, feeding rate variation, and energy consumption. The simulation results showed that: (1) with an outside diameter was 100 mm, the thread pitch 100 mm, and the speed 65 r/min, as the inner diameter increased the feed rate of the spiral feeding device decreased, and the change of average particle filling rate was not obvious; but when the inner diameter was too small or too great, the energy consumption and the fluctuation in particle-filling rate both increased. When the inner diameter was the commonly used size of 50 mm, the performance of feed stability and energy consumption was better; (2) when the outside diameter was 100 mm, the inner diameter 50 mm, and the speed 65 r/min, as thread pitch increased, the feed rate of spiral feeding device increased gradually, and the average particle filling rate decreased slowly, but when the thread pitch was too small or too great, the energy consumption and the fluctuations in particle-filling rate both increased. When the thread pitch of 100 mm was the standard size, the performance of feed stability and energy consumption was better; (3) with an outside diameter of 100 mm and the speed of 65 r/min were unchanged, the inner diameter of 40 mm and the thread pitch of 85 mm were optimal, and the feed-rate stability, energy consumption, and overall performance of the spiral feeding device were superior to other conditions.
Number of references:31
Main heading:Feeding
Controlled terms:Agriculture - Design - Energy efficiency - Energy utilization - Filling - Finite difference method - Optimization - Screws - Shape optimization - Speed - Stability - Structural optimization
Uncontrolled terms:Agricultural productions - Feeding devices - High energy efficiency - Optimization variables - Performance indices - Simulation - Structural parameter - Structure optimization
Classification code:961 Systems Science - 951 Materials Science - 931.1 Mechanics - 931 Classical Physics; Quantum Theory; Relativity - 921.6 Numerical Methods - 921.5 Optimization Techniques - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 801 Chemistry - 691.2 Materials Handling Methods - 605 Small Tools and Hardware - 525.3 Energy Utilization - 525.2 Energy Conservation - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.03.033
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 17>
Accession number:20131416161857
Title:Wind field measurement for supplementary pollination in hybrid rice breeding using unmanned gasoline engine single-rotor helicopter
Authors:Wang, Pei (1); Hu, Lian (1); Zhou, Zhiyan (1); Yang, Weishun (3); Liu, Aimin (4); Luo, Xiwen (1); Xue, Xinyu (5); He, Jie (1); Yan, Yian (1)
Author affiliation:(1) Key Laboratory of Key Technology for South Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (2) College of Engineering, South China Agricultural University, Guangzhou 510642, China; (3) Chinese People's Liberation Army General Staff of the Sixtieth Research Institute, Nanjing 210016, China; (4) Hunan Longping Seed Industry Co. LTD, Changsha 410006, China; (5) Key Laboratory of Crop Protection Machinery, Nanjing Agricultural Mechanization Institute, Ministry of Agriculture, Nanjing 210014, China
Corresponding author:Zhou, Z.(zyzhou@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:54-61
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The unmanned helicopter has been widely used in agricultural plant protection because it is operationally flexible and does not require a special airport. To achieve full mechanization in hybrid rice breeding, it is necessary to expand the planting width of the male and female parents of hybrid rice. The wind made by the helicopter rotor can spread the paternal pollen farther, making it possible to achieve full mechanization in hybrid rice breeding. There are close relationships among the seed setting rate, operating efficiency, cost-effectiveness, and the parameters of the unmanned helicopter flight, including the wind speed, wind direction and wind field width. However, studies are scarce in this area so far. To explore the optimization parameters while the unmanned helicopter conducts supplementary pollination, including flight altitude, operating load, and operating heading, in this study a wireless wind speed sensor network measurement system (WWSSN) was used to measure the wind field of an Unmanned Gasoline Engine Single-Rotor Helicopter (UGESRH). The flight speed of UGESRH was set to 3 m/s, the operating load was 3.75 kg, and the flying heights tested were 9, 8, 7, and 6 m respectively. The measured wind directions of the WWSSN included parallel to the direction of male parent ridge (X), perpendicular to the direction of male parent ridge (Y), and the vertical direction (H). The test results showed that the wind speed value is V<inf>X</inf>>V<inf>Y</inf>>V<inf>Z</inf>, and the wind in direction X is more useful to the supplementary pollination. As the flight altitude decreased, the width of the wind field increased; at operating heights of 6-8 m, the maximum wind field width at wind grade 3 was more than 9 m; when the operating height reached 9 m, the wind field width at wind grade 3 decreased to 4 m. Considering all the various factors together, including the operating efficiency and flight security, a flight height of 7 m is suggested based on the UGESRH-Z3 model unmanned helicopter that we used. The test results also showed that the critical forward wind speed is very small when the UGESRH operates in a headwind, compare with its flight at the downwind direction. Therefore, operation in a headwind is not suggested while using UGESRH to conduct supplementary pollination.
Number of references:30
Main heading:Helicopter rotors
Controlled terms:Air pollution control - Engines - Experiments - Gasoline - Measurements - Mechanization - Plants (botany) - Sensor networks - Unmanned aerial vehicles (UAV) - Wind effects
Uncontrolled terms:Hybrid rice breedings - Operating efficiency - Optimization parameter - Rice seed - Supplementary pollination - Wind field - Wind field measurements - Wind speed
Classification code:652.4 Helicopters - 732 Control Devices - 901.3 Engineering Research - 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 - 652.1 Aircraft, General - 443.1 Atmospheric Properties - 451.2 Air Pollution Control - 461.9 Biology - 523 Liquid Fuels - 601 Mechanical Design - 601.1 Mechanical Devices - 612 Engines
DOI:10.3969/j.issn.1002-6819.2013.03.008
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 18>
Accession number:20131416161868
Title:Comparison of two inversion methods for winter wheat leaf area index based on hyperspectral remote sensing
Authors:Xia, Tian (1); Wu, Wenbin (1); Zhou, Qingbo (1); Zhou, Yong (3)
Author affiliation:(1) Key Laboratory of Agricultural Information Technology, Ministry of Agriculture, Beijing, 100081, China; (2) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (3) College of Urban and Environment Sciences, Huazhong Normal University, Wuhan 430079, China
Corresponding author:Zhou, Q.(zhouqb@mail.caas.net.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:139-147
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Leaf area index (LAI) is an important index for evaluating winter wheat's growth status and forecasting its yield. Hyperspectral remote sensing is a new technical approach that can be used to acquire the information of winter wheat LAI immediately. By integrating hyperspectral remote sensing and traditional field monitoring, this study aims to explore the best simulation accuracy and adaptability to the different method of high spectral monitoring winter wheat leaf area index inversion. Two kinds of universal LAI inversion methods based on hyperspectral remote sensing data through regression analysis method and the BP neural network (BPNN) are introduced and used in this study. The study area is Changqing district of Jinan city, Shandong province, China's Huang-huai-hai plain. On winter wheat growth stage, the winter wheat canopy spectral reflectance and LAI were monitored in field using the ASD FieldSpec 3 and SunScan canopy analysis system. The study selected the following 6 vegetation index (RVI, DVI, NDVI, GRVI, EVI and SAVI) combined with spectral reflectance characteristics of the study area. The 6 vegetation indexes are closely related to winter wheat LAI with correlation at a significant level. After correlation analysis of the Hyperspectral Vegetation Index (HVI) and LAI, winter wheat LAI regression models and BPNN model were established. Then simulation precisions for different models were analyzed and evaluated. The 6 winter wheat LAI regression models fits were 0.696~0.775, and root mean square errors (RMSE) were 0.386-0.523. Accuracy test showed that NDVI inversion model had the highest accuracy compared to other models. It is concluded that NDVI model is the most suitable model for inverting winter wheat LAI in the study area. However, the NDVI inversion model must avoid saturation phenomenon when NDVI is close to 1. This is the model's inadequacy. Input multiple sensitive reflectivity bands contain 450, 550, 670 and 870 nm bands to the BP neural network model. Upon examination, the simulation and measured fit values was 0.990 and the RMSE was 0.105. The results show that BP neural network model inversion method can build a better LAI inversion for winter wheat varieties in different regions. Among them, the inversion model has the highest R<sup>2</sup> (0.990) and least RMSE (0.105). The BP neural network method used to construct the inversion model is better on different varieties of winter wheat LAI inversion. However, establishing BP model needs to ensure enough samples (generally the number of samples n>50 is a large sample of events) for the research adaptability. Both methods have their advantages and disadvantages. Overall, inversion method should be selected according to the number of samples and monitoring area.
Number of references:29
Main heading:Computer simulation
Controlled terms:Crops - Estimation - Mean square error - Neural networks - Reflection - Regression analysis - Remote sensing - Statistics
Uncontrolled terms:Hyperspectral remote sensing - Hyperspectral remote sensing data - Hyperspectral vegetation indices - Inversion methods - Leaf Area Index - Regression analysis methods - Root mean square errors - Winter wheat
Classification code:922.2 Mathematical Statistics - 921 Mathematics - 821.4 Agricultural Products - 731.1 Control Systems - 723.5 Computer Applications - 723.4 Artificial Intelligence - 711 Electromagnetic Waves
DOI:10.3969/j.issn.1002-6819.2013.03.019
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 19>
Accession number:20131416161861
Title:Influence of TiCN/Fe metal ceramic coating by reaction nitrogen arc cladding on wear resistance of agricultural tools
Authors:Zhao, Jianguo (1); Li, Jianchang (1); Hao, Jianjun (1); Ma, Yuejin (1); Feng, Xianqin (2)
Author affiliation:(1) College of Mechanical and Electric Engineer, Agriculture University of Hebei, Baoding 071001, China; (2) Zhangjiakou Vocational and Technical College, Zhangjiakou 075000, China
Corresponding author:Zhao, J.(zjg@hebau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:84-89
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:There is a current problem that agricultural tools easily get worn and frequently lose effectiveness. In order to solve this problem, the TiCN/Fe metal ceramic coating had been successfully prepared on a Q235 steel specimen surface by a reaction nitrogen arc cladding technique with a TXII500 argon arc welding machine. In the coating preparation, the industrial titanium powder and the graphite powder (300 mesh, a purity of 98%) are mixed at the ratio of 47.9: 12 in weight with 6 hours through the DQM type planetary ball mill, and precoated on the specimen surface. The precoated thickness is 2±0.2 mm, and the industrial N2 (purity 99.999%) is used as a reaction and protection gas. The coating was prepared on the surface of a specimen based on the high temperature of the nitrogen arc which made the N2 and precoated powder react in the course of welding. Effects of cladding speed (1.5, 2.0, 3.0 mm/s) on morphology, phase, and microhardness of the TiCN/Fe coating were analyzed by means of a scanning electronic microscope (SEM), X-ray diffractometer (XRD), and microhardness gauge, and contrast tests of wear were done between agricultural tools and coating. The results showed that the surface of the coating can obtain good morphology when the cladding speed is 1.5 mm/s, but when the coating contains less TiCN and the microhardness of coating is low; with the increase of the cladding speed(such as 3.0 mm/s), the coating morphology is worse off, but the microhardness and wear resistance have been increased obviously. The microhardness on the coating surface could reach up to HV0.5 1089, about 3 times as much as Q235 microhardness. Contrasted with common agricultural tools material (65 Mn), the wear loss is only 1/2 times as 65Mn, and the coating wear resistance is better. The coating can be used on agricultural tools for improving the service life of tools.
Number of references:24
Main heading:Surface reactions
Controlled terms:Agricultural implements - Agricultural machinery - Ball mills - Ceramic coatings - Cladding (coating) - Coatings - Electric welding - Manganese - Microhardness - Microstructure - Morphology - Nitrogen - Specimen preparation - Steel research - Surfaces - Wear resistance
Uncontrolled terms:Coating morphology - Current problems - Nitrogen arcs - Planetary ball mill - Scanning electronic microscopes - Specimen surfaces - Titanium powders - X ray diffractometers
Classification code:821.1 Agricultural Machinery and Equipment - 813.2 Coating Materials - 804 Chemical Products Generally - 802.2 Chemical Reactions - 802.1 Chemical Plants and Equipment - 951 Materials Science - 545.3 Steel - 539 Metals Corrosion and Protection; Metal Plating - 538.2.1 Welding Processes - 538.1 Metal Bonding - 421 Strength of Building Materials; Mechanical Properties - 543.2 Manganese and Alloys
DOI:10.3969/j.issn.1002-6819.2013.03.012
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 20>
Accession number:20131416161885
Title:Effects of tea tree oils on removing pesticide residue in cowpea
Authors:Lin, Lijing (1); Cheng, Shenghua (1); Li, Jihua (1); Huang, Maofang (1); Tang, Yongfu (1); Zhu, Deming (1)
Author affiliation:(1) Key Laboratory of Tropical Crop Products Processing, Ministry of Agriculture, Zhanjiang 524001, China; (2) Inspection Center of Food Quality (Zhan Jiang), Ministry of Agriculture, Zhanjiang 524001, China
Corresponding author:Zhu, D.(demingzhu@gmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:273-278
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Pesticides are widely used as an insurance policy against devastating crop losses from pests and diseases. Excessive usage of pesticides may lead to contamination of the crop and the environment, eventually posing a risk of pesticide-related illnesses to humans. Previous literature has shown that water washing is only partially effective in removing pesticides, and in the case of liposoluble pesticides, a cosolvent must be used as an adjuvant. Recently, naturally occurring adjuvants are gaining prominence over synthetic chemical compounds. Tea tree oil (TTO, the oil of Melaleuca alternifolia), a natural, volatile essential oil, is mainly extracted by steam distillation from the fresh leaves and terminal branchlets of the plant. It has attracted significant interest due to its antifungal, antiviral, and antibacterial bioactivities. However, to the best of our knowledge, there are fewer experimental data evaluating its efficacy in the removal of pesticide residues. In this study, the effects of TTO on removing pesticide residue were carried out in the cowpea. Volume: volume (v: v) concentrations of 0.05%, 0.1%, 0.2%, 0.4% and 0.8% of TTO and water soluble tea tree oil (WTTO) in water were used to remove a standardized pesticide mixture (organophosphorus, pyrethroid, and carbamate compounds) from cowpeas. Sample pretreatment (pesticide application to cowpeas) was performed according to agricultural industry standards. The objective pesticide residues in cowpeas were assayed by gas chromatography (GC) and chromatography-mass spectrometry detection (GC-MS), and then the clearance rate was calculated. The results showed that TTO was able to remove the three kinds of pesticides from cowpeas. Moreover, the removal efficiency increased with increasing concentration of TTO. The effect of clearing organophosphate was much more obvious than that of either pyrethroid or carbamate. It was suggested that small liposoluble molecules of TTO rapidly infiltrate the cowpea surface to dissolve the organophosphate pesticides depending on the compatibility principle. For carbamate pesticides, such as carbofuran, owing to its high polarity, TTO could not infiltrate into the internal of cowpeas to dissolve the residuals, resulting in the lower clearing efficiency. In conclusion, to remove pesticide residues, the commercially available extract TTO was more effective than deionized water in removing pesticide residues from fruits and vegetables. In comparison, WTTO was even more effective in removing pesticide residues than the same concentration of TTO. Among all treatments, 0.8% WTTO showed the greatest removal efficiency. The removal rates achieved by WTTO were as follows: 80.48% for isocarbophos, 94.54% for malathion, 82.79% for triazophos, 84.58% for chlorpyrifos, 72.20% for omethoate, 80.51% for cypermethrin, and 72.21% for meta-tolyl-N-methylcarbamate (MTMC). Therefore, TTO is expected to be useful as a fruit and vegetable cleaning adjuvant.
Number of references:29
Main heading:Pesticides
Controlled terms:Chemical compounds - Crops - Deionized water - Distillation - Essential oils - Forestry - Fruits - Gas chromatography - Insurance - Plants (botany) - Removal - Vegetable oils - Water pollution
Uncontrolled terms:Carbamate - Cowpea - Organoposphorous - Pyrethroids - Tea tree oil
Classification code:911.1 Cost Accounting - 821.4 Agricultural Products - 821.0 Woodlands and Forestry - 804.1 Organic Compounds - 803 Chemical Agents and Basic Industrial Chemicals - 802.3 Chemical Operations - 461.9 Biology - 453 Water Pollution - 445.1 Water Treatment Techniques
DOI:10.3969/j.issn.1002-6819.2013.03.036
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 21>
Accession number:20131416161858
Title:Calculation and simulation of air mass flow for turbocharged diesel engines
Authors:Huang, Fenlian (1); Ji, Wei (1); Zhou, Wei (2)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing 100083, China; (2) Institute of Road Research, Ministry of Transport of the People's Republic of China, Beijing 100088, China
Corresponding author:Ji, W.(jiwei21st@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:62-68
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Air mass flow determination is a major issue for matching of turbocharger and dynamic simulation of diesel engine system. Generally speaking, there are two kinds of mean value models of air mass flow. One is based on the amount of air for fuel combustion, which involves engine power, fuel consumption rate, instantaneous excess air ratio and coefficient of scavenging; and the other is on the basis of the definition of volumetric efficiency, which relates to piston swept volume, air density and coefficient of scavenging. However, different purpose and conditions of research form various mathematical models of air mass flow, and the results of calculation varied wildly. In order to get the optimum simulation model, different mean value models of air mass flow were comprehensively compared and further analyzed in this paper. Furthermore, the influence of turbocharger, intercooler, exhaust gas recirculation rate, volumetric efficiency and operation condition were particularly taken fully into account. Firstly, relative condition correction was carried out for the first type of original models to make them can be applied to any operating condition beyond the rated condition. The precision of models were remarkably improved through multiplying the original models by the ratio of engine speed under any operating condition to rated speed. Secondly, by considering the effect of exhaust gas, the mass conservation equation was rebuilt, and then the correctional formula of air mass flow for turbocharged diesel engines which were equipped with exhaust gas recirculation system were derived. Finally, part of the above models were modified via taking account of the influence of combustion chamber geometry, compression ratio, cooling efficiency and scavenging efficiency on volumetric efficiency. Meanwhile, all the mathematical models were simulated with Matlab/Simulink and verified through comparing the simulation results with experimental values. Eventually, the simulation and experimental results show that the air mass flow model after revising fit well with the actual situation. In addition, the average relative error of the optimal model is 2.96% and therefore the design of model is reasonable and accurate. Consequently, the results of this study will be helpful to accurately calculate the air mass flow of turbocharged diesel engine, and provide useful reference for its model selection.
Number of references:31
Main heading:Diesel engines
Controlled terms:Calculations - Combustion chambers - Compression ratio (machinery) - Computer simulation - Efficiency - Exhaust gas recirculation - Flow measurement - Fuels - Mass transfer - Mathematical models - Superchargers - Turbomachinery
Uncontrolled terms:Air mass - Average relative error - Exhaust gas recirculation rates - Exhaust gas recirculation systems - Fuel consumption rates - Mass conservation equations - Turbocharged - Turbocharged diesel engine
Classification code:921 Mathematics - 913.1 Production Engineering - 723.5 Computer Applications - 654.2 Rocket Engines - 641.3 Mass Transfer - 943.2 Mechanical Variables Measurements - 618.1 Compressors - 612 Engines - 524 Solid Fuels - 523 Liquid Fuels - 522 Gas Fuels - 618 Compressors and Pumps
DOI:10.3969/j.issn.1002-6819.2013.03.009
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 22>
Accession number:20131416161877
Title:Antibacterial mechanism of cow manure biogas slurry on Rhizoctonia solani
Authors:Li, Wentao (1); Fan, Jinxia (1); Li, Wenzhe (1); Yuan, Hu (1)
Author affiliation:(1) College of Engineering, Northeast Agriculture University, Harbin 150030, China
Corresponding author:Li, W.(liwenzhe9@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:207-212
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to investigate the antibacterial mechanism of biogas slurry, Rhizoctonia solani was cultured at 28°C for 96 h using potato dextrose agar medium in the center of Petri dishes that coated uniformly with 1 mL different treatments biogas slurry. 5 treatments of biogas slurry were applied as follows: 1) Biogas slurry without treatment; 2) Biogas slurry sterilization under 121°C for 20 min; 3) Centrifugal supernatant at 12 000 r/min for 10 min; 4) Filtrate from centrifugal supernatant by 0.22 μm membrane; 5) Microbes solution, precipitate from high speed centrifugation of 4 mL biogas slurry washed 3 times with sterilized water to remove the chemical and bioactive substances and added with sterilized water to 4 mL. The colony diameters of Rhizoctonia solani were measured at 12 h intervals and the inhibitory rates were calculated. The inhibitory rate equals to the diameters of control colony subtracted the diameters of treated colony then divided by the diameters of control colony, at last multiply 100%. Origin8.1 and excel were used to analysis the data. Molecular biology technique was also used to identify the microbes which had inhibitory effect on Rhizoctonia solan,. The sequence analysis was based on the BLASTN of United States National Center for Biotechnology Information and software MEGA4.0. The results showed that all inhibitory rates of different treated biogas slurry rose quickly at the beginning, then reached a maximum value, and decreased slowly with the similar trend at last. Sterilization treatment got the lowest inhibitory rate, usually less than 13%, supernatant and membrane filtration treatments were below 20%, biogas slurry without treatment has the higher inhibitory rate of 53%, and the microbe solution treatment obtained the highest inhibitory rate of 74%. The microbe solution treatment also showed the most durable inhibitory effect which lasted for about 96 h. 16 kinds of microbe named as nfd-1 to nfd-16 were separated from biogas slurry by 10 time's dilution method. They were 8 kinds of fungi, 5 kinds of bacteria and 3 kinds of actinomyces, and their antagonism effects with Rhizoctonia solani were investigated respectively. The results showed that the fungi nfd-9 and nfd-16 had strong inhibitory effect on Rhizoctonia solani, however, the others had almost no inhibitory effect. Scanning electron microscopy was used to survey the interface of nfd-9 and nfd-16 with Rhizoctonia solani. It was found that nfd-9 and nfd-16 inhibit the growth of Rhizoctonia solani through the effects of competitions, antagonism, and hyperparasitism to prevent the crops diseases. Nfd-9 and nfd-16 were finally identified as Rhizopus oryzae and Trichoderma harzianum by molecular biology technique. The results can provide a theoretical reference for further understanding the fungal inhibitory mechanism of biogas slurry.
Number of references:26
Main heading:Biogas
Controlled terms:Bacteria - Biophysics - Centrifugation - Disease control - Fungi - Fungus resistance - Manures - Microfiltration - Molecular biology - Scanning electron microscopy - Sterilization (cleaning)
Uncontrolled terms:Biogas slurry - Plants - Rhizoctonia solani - Rhizopus oryzae - Trichoderma harzianum
Classification code:931 Classical Physics; Quantum Theory; Relativity - 802.3 Chemical Operations - 701 Electricity and Magnetism - 522 Gas Fuels - 461.9 Biology - 461.7 Health Care - 452.3 Industrial Wastes
DOI:10.3969/j.issn.1002-6819.2013.03.028
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 23>
Accession number:20131416161872
Title:Design and experiments of automatic feeding system for indoor industrialization aquaculture
Authors:Yuan, Kai (1); Zhuang, Baolu (1); Ni, Qi (1); Wu, Fan (1)
Author affiliation:(1) Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200092, China; (2) College of Engineering, Shanghai Ocean University, Shanghai 201306, China; (3) Key Laboratory of Fishery Equipment and Engineering, Shanghai 200092, China
Corresponding author:Ni, Q.(niqi@fmiri.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:169-176
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to meet the feeding needs of industrialization aquaculture system, an automatic feeding system was designed and developed applying the monorail technique, the slide rail power supply technique, the ultrasonic positioning technique, the wireless communication technique and the computer software technique. The system was composed of a running system, a power supply system, a feeding equipment and a control system. The feeding system with the function of auto detecting and error alarm could be automatic start and stop, weigh feeding amount and record system operation and feeding data automatically. The running system was mainly composed of a monorail likes a raceway made by H-shape steel, an electric pulley block and an ultrasonic positioning sensor. The four T forging steel rail wheels of the electric pulley block ran on the lower wing plate of H-shape steel. One reflecting plate (80 mm×150 mm) was installed on the monorail corresponded to each rearing tank. The number of each rearing tank was identified by the different distance between each reflecting plate and ultrasonic sensor moving with the electric pulley block. The feeding device comprised a hopper, stepper motor, a gate and four weighing sensors. Four sensors hung up the hopper to the electric pulley block and weighed the mount of the hopper. Opening and closing of the gate was controlled by the changes of the hopper weight. The design calculation showed that when using HW100×100 steel monorail, with the diameter of 0.06 m T forging steel rail wheels, gear ratio 20: 1 gear transmission group and 24 V DC motor to drive the system to moving on the monorail, the motor power must be more than 0.2 kW, speed was 2 000 r/min, output torque requirements must be over 0.58 N · m. The automatic feeding system prototype was designed by Solidworks, and the prototype was tested for the feeding amount accuracy and positioning deviation. The experiments showed that the feeding system was reliable and accurate for feeding with travelling speed 19 m/min, positioning accuracy was in the range of 58-118 mm, bullet storage capacity was 20 kg, feeding capacity was 3 kg/min and feeding accuracy was in the range of 0.5%-2.2%. The system effectively improves the feeding accuracy, reduces the feed waste, abates the labor intensity, and meets the needs of industrialization aquaculture system at the direction of the mechanization and automation. Future improvement will include a smoother monorail without seams and speeding the response of the electrical components to improve the accuracy of feeding and positioning. The results of this research provide a reference for the automatic feeding system design and the related follow-up research.
Number of references:25
Main heading:Feeding
Controlled terms:Aquaculture - DC motors - Design - Digital storage - Electric power systems - Equipment - Experiments - Forgings - Hoppers - Machinery - Monorails - Pulleys - Rails - Sensors - Tanks (containers) - Torque motors - Tracking (position) - Wireless telecommunication systems
Uncontrolled terms:Automatic feeding - Automatic feeding systems - Electrical components - Feeder - Running systems - Timing and quantitative - Ultrasonic positioning - Wireless communication techniques
Classification code:706.1 Electric Power Systems - 716 Telecommunication; Radar, Radio and Television - 716.2 Radar Systems and Equipment - 717 Optical Communication - 722.1 Data Storage, Equipment and Techniques - 801 Chemistry - 821.3 Agricultural Methods - 901 Engineering Profession - 901.3 Engineering Research - 705.3.2 DC Motors - 408 Structural Design - 535.2 Metal Forming - 601 Mechanical Design - 619.2 Tanks - 681.1 Railway Plant and Structures, General - 682.1 Railroad Rolling Stock, General - 691.1 Materials Handling Equipment - 691.2 Materials Handling Methods - 705.3 Electric Motors
DOI:10.3969/j.issn.1002-6819.2013.03.023
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 24>
Accession number:20131416161864
Title:Water sensitivity of shear strength of purple paddy soils
Authors:Hu, Feinan (1); Wei, Chaofu (1); Xu, Chenyang (2); Wei, Nengqiao (3); Zhong, Mang (1); Zhong, Shouqin (1)
Author affiliation:(1) Key Laboratory of Arable Land Conservation (Southwest China), Ministry of Agriculture, Chongqing 400715, China; (2) College of Resources and Environment, Southwest University, Chongqing 400715, China; (3) School of Physical Science and Technology, Southwest University, Chongqing 400715, China
Corresponding author:Wei, C.(weicf@swu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:107-114
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Soil shear strength is one of the most important indicators in engineering design and soil erosion, also an essential parameter for soil precision tillage and design of agricultural machinery and equipment. In the previous work, although the shear strength of several types of soils has been investigated, few of these researches include that of purple paddy soils. Compared with purple soils, purple paddy soils have long been submerged in natural conditions; this special characteristic must have far-reaching influence on the mechanical properties of soils. Therefore, to investigate the water sensitivity of shear strength of purple paddy soils which are widely distributed over the Territorial Management Project in the Dazhu village, Qiantang town, Hechuan district in Chongqing, their shear strength was measured through triaxial test by considering the change of moisture directly, and accordingly some suggestions were put forward in dealing with purple paddy soil for engineering construction. In batch experiment, soil samples collected from the roadbed in the project were first air-dried, and after removal of visible pieces of plant debris and stones, all of the samples were ground to pass a 2-mm sieve for subsamples. According to test requirements, the water content of the subsamples was pre-adjusted to the required values carefully in preparation for triaxial compression test. Then unconsolidated undrained (UU) triaxial compression test was conducted under four different confining pressure (100, 200, 300, 400 kPa) using groups of samples at eight distinctive soil water contents (9%, 11%, 13%, 15%, 17%, 20%, 21% and 23%). The results indicated that: 1) The principal stress of purple paddy soils increases with the decrease of moisture under the same confining pressure, and the principal stress increases with the increasing confining pressure under the same water content, in which the increments become smaller with increasing soil water content. 2) When the water content of purple paddy soil is around a critical value, the variation of shear strength is slight; while the water content is above the critical value, the shear strength of purple paddy soils decrease with increasing water content. 3) The water content of purple paddy soil is of great significance on its cohesion. The number of cohesive strength peaks at 176.2 kPa at 13% and ends at 80.2 kPa at 23%. 4) The internal friction angle is negatively linearly correlated with soil water content (from 30.2° at 9% to 4.9° at 23%). This information confirms that purple paddy soils are water-sensitive, which is also beneficial to the reasonable design of local agricultural infrastructure.
Number of references:33
Main heading:Shear strength
Controlled terms:Agricultural machinery - Agriculture - Compression testing - Design - Experiments - Mechanical properties - Precision engineering - Project management - Rock pressure - Soil moisture - Underwater soils - Water content
Uncontrolled terms:Confining pressures - Different confining pressures - Engineering constructions - Internal friction angle - Purple paddy soils - Tri-axial compression tests - Triaxial test - Water sensitivity
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 912.2 Management - 901.3 Engineering Research - 821.1 Agricultural Machinery and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 951 Materials Science - 761 Nanotechnology - 444 Water Resources - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties - 408 Structural Design - 483.1 Soils and Soil Mechanics
DOI:10.3969/j.issn.1002-6819.2013.03.015
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 25>
Accession number:20131416161852
Title:Principle analysis and parameters optimization of rotary rice pot seedling transplanting mechanism
Authors:Yu, Gaohong (1); Huang, Xiaoyan (1); Ye, Bingliang (1); Hu, Haijun (1); Yu, Tengfei (1)
Author affiliation:(1) Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou, 310018, China
Corresponding author:Yu, G.(yugh@zstu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:16-22
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Rice pot seedling transplanting is a transplanting technology with pot seedling, which plays an important part in the process of rice cultivation. However, compared with other countries and regions, mechanization level of rice cultivation in China is relatively low, and degree of mechanization is also the lowest compared to other domestic rice production processes. Therefore the study of a new rice pot seedling transplanting mechanism has a very important significance in mechanized cultivation and high-yielding of rice. By analyzing the shortcomings and deficiencies of the existing rice pot seedling transplanters at home and abroad, discussing the features and benefits of the rice pot seedling transplanter, this paper came up with a new type of rice pot seedling transplanting mechanism of planetary gear train with ellipse gears and incomplete non-circular gear, and it helped the rice pot seedling transplanting to achieve high yield and efficiency level. Firstly, the work principle of this transplanting mechanism was analyzed, the kinematics model of planetary gear train with ellipse gears and incomplete non-circular gears was established. Then, based on Visual Basic6.0, a computer-aided analysis and optimization software for the transplanting mechanism was developed. Finally, through analyzing the influences caused by the input parameters, using the man-machine interactive optimization method, a group of structural parameters were found to meet the requirements of transplanting rice pot seedling.
Number of references:28
Main heading:Gears
Controlled terms:Computer aided analysis - Design - Machinery - Mechanisms - Mechanization - Optimization
Uncontrolled terms:Non-circular gears - Planetary gear train - Rice pot seedling - Rotary - Transplanters
Classification code:408 Structural Design - 601 Mechanical Design - 723.5 Computer Applications - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2013.03.003
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 26>
Accession number:20131416161875
Title:Effects of different catalysts on steam gasification of biomass char at low temperature
Authors:Yu, Yuanyuan (1); Xiao, Jun (1); Shen, Laihong (1); Du, Yuzhao (1)
Author affiliation:(1) Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education, Thermoenergy Engineering Research Institute, Southeast University, Nanjing 210096, China
Corresponding author:Xiao, J.(jxiao@seu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:190-197
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The low-temperature catalytic gasification of biomass is a promising technology for hydrogen production from the energy point of view due to its relatively low heat input. And it has attracted the worldwide interests. However, the lower char conversion efficiency and higher tar yield at low-temperature are unsolved problems to the technical application of low-temperature catalytic gasification. In order to overcome these issues, numerous researches are being focused on the catalyst development. As the studies concerning catalytic gasification of biomass char under relatively low temperature (T&le750°C) are fairly limited, catalytic gasification of two biomass char samples, rice husk and wheat straw, were investigated at relatively low temperature in this paper. The impregnated alkali metal catalysts were prepared in this study. In which, Al<inf>2</inf>O<inf>3</inf> was used as carrier of the catalyst, and potassium carbonate and sodium carbonate were used as active ingredient, respectively. In addition, the catalyst components were detected by X-ray diffraction analysis (XRD). Using the prepared catalysts, catalytic steam gasification of biomass char was carried out in a lab-scale fluidized bed reactor at the temperature between 600°C and 700°C to investigate the performance of catalysts. And the effects of catalyst parameters including active ingredient, ingredient contents and calcination temperature, and gasification temperature on the behavior of char gasification were also studied. The results revealed that both potassium based catalyst and sodium based one have significant catalytic action on biomass char conversion. Moreover, potassium based catalyst exhibited better catalytic performance than sodium based one with the same content of active component in rice husk char gasification process. Compared with non-catalytic rice husk char gasification, carbon conversion efficiency was increased by 18.2% and 13.5% using 30KAl(600) and 30NaAl(600), respectively. Increasing K<inf>2</inf>CO<inf>3</inf> content was beneficial to improving char conversion efficiency, and also increasing CO and H<inf>2</inf> yield. However the active component contents were inadvisable beyond 30%. The catalyst prepared at different calcination temperature generated the different existing forms of active components. 30KAl(800) catalyst calcinated at 800°C showed the optimal catalytic action on the char gasification. X-ray diffraction analysis (XRD) showed that the 30KAl(800) catalyst contained K<inf>2</inf>Al<inf>2</inf>O<inf>2</inf> (CO<inf>3</inf>)<inf>2</inf>·3H<inf>2</inf>O, and thus it may be a more effective component. The results showed that both gas yield and carbon conversion efficiency of wheat straw char were higher than those of rice husk char under the same gasification conditions. Thus it also reveals that alkali metal contained in biomass ash has catalytic action on char gasification. The gas yield and carbon conversion efficiency of wheat straw char reached 130.0 mol/kg-char and 95.9% respectively using 30KAl(800) catalyst at the gasification temperature of 700°C, which were 57.0% and 34.1% higher than those of non-catalytic gasification. It was also found that the gas yield and carbon conversion efficiency significantly reduced with decrease of gasification temperature. When gasification temperature was decreased to 600°C, the carbon conversion efficiency was only 19.1% using 30KAl(800) catalyst. Thus it was not appropriate for gasification at temperature below 700°C based on the study.
Number of references:30
Main heading:Gasification
Controlled terms:Biomass - Calcination - Carbon - Catalysts - Chemical reactors - Conversion efficiency - Energy resources - Fluid catalytic cracking - Hydrogen production - Potassium - Sodium - Temperature - X ray diffraction analysis
Uncontrolled terms:Biomass char - Calcination temperature - Catalytic gasification - Catalytic steam gasifications - Fluidized bed reactors - Gasification temperatures - Technical applications - X-ray diffraction analyses (XRD)
Classification code:802 Chemical Apparatus and Plants; Unit Operations; Unit Processes - 801 Chemistry - 641.1 Thermodynamics - 804 Chemical Products Generally - 549.1 Alkali Metals - 525.1 Energy Resources and Renewable Energy Issues - 522 Gas Fuels - 525.5 Energy Conversion Issues
DOI:10.3969/j.issn.1002-6819.2013.03.026
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 27>
Accession number:20131416161879
Title:Analysis on influence factors of soil Pb and Cd in agricultural soil of Changsha suburb based on geographically weighted regression model
Authors:Liu, Qiongfeng (1); Li, Mingde (2); Duan, Jiannan (1); Wu, Haiyong (2); Hong, Xi (2)
Author affiliation:(1) College of Resource and Environment, Hunan Agricultural University, Changsha 410128, China; (2) Soil and Fertilizer Institute of Hunan Province, Changsha 410125, China
Corresponding author:Duan, J.(duanjn@hunau.net)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:225-234
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Contamination of suburban, agricultural soils with heavy metals draws great attention because of its potential threat to food safety and its detrimental effects on the ecosystem. The origins of soil heavy metals in the suburban interface are usually controlled by many factors, such as parent material, industrial activities, and agriculture. To decrease heavy metals pollution risks effectively in suburban areas and further to establish reliable protection measures, it is quite necessary to understand their sources and spatial patterns. The ordinary linear regression model (OLS) has been frequently used to analyze the relationship between soil heavy metals and their influential factors. However, OLS is only in a global or an average sense to estimate parameters, and it is unable to reflect spatial local variation or test spatial non-stationarity.Geographically weighted regression models (GWR) are a powerful tool for exploring spatial heterogeneity. The underlying idea of GWR is that parameters may be estimated anywhere in the study area given a dependent variable and a set of one or more independent variables which have been measured at known locations. Not only can it test spatial non-stationarity, but it can also provide the corresponding solutions. As a local model, GWR modeling has been applied in research on urban housing land prices and the spatial factors of economic development, but it has seldom been applied to the origins and spatial structure of soil heavy metals. A survey was conducted in this study to determine the possible sources of heavy metals in agricultural soils of the suburban area of Changsha. A total of 513 surface soil samples were collected, and the concentrations of Pb and Cd were analyzed. Typical influences on soil Pb and Cd concentration were identified from soil properties and geographic locations, such as soil pH, organic matter, alkali-hydro nitrogen, rapidly available phosphorus, rapidly available potassium, slowly available potassium, the distance from cropland to town, the distance from cropland to settlement, the distance from cropland to industrial construction sites, and the distance from cropland to a river. The OLS and GWR were applied to determine the relationships among both the influential factors and their spatial structure. The results indicate that spatial autocorrelations were detected for Pb and Cd. The high-high spatial clusters districts had high concentrations of Pb and Cd and were the most important regions for controlling the pollution risk of Pb and Cd in agricultural soil of the suburban area of Changsha. The GWR models for Pb and Cd had a better goodness-of-fit than OLS models and indicated the same tendency of spatial correlation between the Pb and Cd measured values with their estimated values. Soil Pb was highly significantly and positively related with Cd. The concentrations of soil pH, organic matter, alkali-hydro nitrogen and rapidly available phosphorus were the important influential factors for the content of Pb and Cd. The distance from cropland to river, from cropland to town, and from cropland to construction sites also had some influence on the concentrations of Pb and Cd in the agricultural soils of suburban Changsha.
Number of references:30
Main heading:Soil pollution
Controlled terms:Agriculture - Biogeochemistry - Biological materials - Cadmium - Cadmium compounds - Civil engineering - Geologic models - Interfaces (materials) - Lead - Linear regression - Models - Nitrogen - Organic compounds - Potassium - River pollution - Soils - Space applications
Uncontrolled terms:Corresponding solutions - Farmland - Geographically weighted regression models - Heavy metals pollution - Industrial construction - Linear regression models - Spatial autocorrelations - Spatial non-stationarity
Classification code:549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 656 Space Flight - 804 Chemical Products Generally - 951 Materials Science - 804.1 Organic Compounds - 902.1 Engineering Graphics - 922.2 Mathematical Statistics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 549.1 Alkali Metals - 546.1 Lead and Alloys - 409 Civil Engineering, General - 453 Water Pollution - 461.2 Biological Materials and Tissue Engineering - 481.1 Geology - 481.2 Geochemistry - 483.1 Soils and Soil Mechanics
DOI:10.3969/j.issn.1002-6819.2013.03.030
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 28>
Accession number:20131416161866
Title:Evaluation of vegetation and soil characteristics during slope vegetation recovery procedure
Authors:Zhang, Yan (1); Zhao, Tingning (1); Shi, Changqing (1); Wu, Hailong (1); Li, Danxiong (1); Sun, Yongkang (1)
Author affiliation:(1) School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
Corresponding author:Zhao, T.(zhtning@bjfu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:124-131
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In recent years, the implementation of the development and construction projects has destroyed original ecological barrier, which results in a series of environmental problems, such as water losses and soil erosion, landslide, vegetation coverage degradation and diversity of species decrease, which will endanger human life and property safety. It is urgent and necessary to figure out the relationship between soil properties and vegetation growth, based on which measures can be designed and conducted to maintain stability and sustainable development of natural environment, as well as to recover or reconstruct the sites impaired by construction projects, and then keep life and property from threat damaged. In this study, 20 typical slope protection districts in Soil and Water Conservation Science and Technology Demonstration Park in Shangxinzhuang, Yanqing county of Beijing were chosen as evaluation units. Several parameters related to vegetation recovery were simplified into four independent principal components with specific functions using principal components analysis (PCA) method, including vegetation characteristics, soil physical properties, soil chemical properties and site conditions. Principal component scores were used for cluster analysis, and the 20 districts were divided into 3 groups. The comprehensive scores of every protection district were identified by using scores of 4 principal components and the corresponding eigenvalue weights, and then they were combined with the results of cluster analysis to assess the vegetation recovery effect of 3 types of slope protection districts. Margalef richness index, Pielou evenness index, Simpson index and Shannon-Wiener diversity index were used to evaluate inter-annual differentiation characteristics of vegetation community in different groups of districts and to construct 5 prediction models with different vegetation-soil degrees of coupling, within which the effects from both soils and plants were integrated. The results showed that: 1) Group I and Group II of districts, which mainly consisted of soil slopes, had significantly better vegetation restoration effect compared to Group III, which mainly consisted of rock slopes. 2) With the passage of time, the diversity index increased, the coefficient of variation decreased, and vegetation succession processed in a more dramatic manner in all groups of districts. 3) After 5 years of recovery, the vegetation-soil coupling coordination degrees of all districts achieved not so good coordinated development stage. Group I and Group II belonged to intermediate coordinated development stage, while Group III belonged to primary coordinated development stage. The vegetation-soil systems of all 3 groups of districts were in a transition period from primary coordinated development towards to intermediate coordinated development. The method of simplifying vegetation recovery factors by CPA combined clustering analysis to divide protection slope type is effective and it can not only ensure the data comprehensive, but also confirm the typicality when evaluating the vegetation recovery effect. In addition, the model constructed by soil properties and vegetation properties combined soil and vegetation system suitably which can evaluate the vegetation recovery effect in all protection districts. This research can guide the vegetation recovery of slopes damaged by construction projects for governors and executors. Measures of vegetation restoration in bare slopes and inner relationship of vegetation-soil need further investigation in the future.
Number of references:22
Main heading:Vegetation
Controlled terms:Cluster analysis - Couplings - Eigenvalues and eigenfunctions - Environmental protection - Forestry - Geologic models - Models - Principal component analysis - Recovery - Restoration - Slope protection - Soils - Water conservation
Uncontrolled terms:Coefficient of variation - Development and construction projects - Evaluation - Principal components analysis - Shannon-wiener diversity indices - Soil and water conservation - Soil physical property - Vegetation successions
Classification code:723 Computer Software, Data Handling and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 902.1 Engineering Graphics - 921.1 Algebra - 922 Statistical Methods - 922.2 Mathematical Statistics - 602 Mechanical Drives and Transmissions - 402 Buildings and Towers - 409 Civil Engineering, General - 444 Water Resources - 454.2 Environmental Impact and Protection - 481.1 Geology - 483.1 Soils and Soil Mechanics - 531 Metallurgy and Metallography
DOI:10.3969/j.issn.1002-6819.2013.03.017
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 29>
Accession number:20131416161874
Title:Fishway effect of Cuijiaying navigation-power junction project
Authors:Wang, Ke (1); Liu, Shaoping (1); Duan, Xinbin (1); Sun, Mingshuai (2); Ye, Chao (3); Chen, Daqing (1)
Author affiliation:(1) Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Science, Wuhan 430223, China; (2) College of Fisheries, Huazhong Agriculture University, Wuhan 430070, China; (3) College of Life Science, Southwest University, Chongqing 400715, China
Corresponding author:Chen, D.(chdq@yfi.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:184-189
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The Cuijiaying navigation-power junction project is located at the Hanjiang River. Its functions include, but are not limited to, navigation, power generation, and irrigation. In order to compensate for the adverse effect of the project on the fishery resource, a fish passage was built. To realize the effect of the fish passage, an investigation was conducted September 19-26, 2012 and the methods of net catch and hydroacoustic monitoring were adopted. Trammel nets were used for fish catching in the fishway. The net was comprised of three layers and the dimensions of the net were 15m×1.2m. The mesh of the middle layer was 4mm and the mesh of the outer two layers was 8mm. Nets were laid at the orifices of the baffle plate and six nets were put out every day, three in the daytime and the other three in the nighttime. The first net was put in the exit of the Cuijiaying fishway and the distance between the net and the exit was 8 meters. The distance of the other two nets to the exit was 18 meters and 28 meters. Hdroacoustic equipment of SIMRAD EY60 was adopted at the front of the exit to see the quantity of fish which can swim across the entire fish passage. The frequency of the equipment was 200 kHz and the angle of the beam was 7°. The equipment was fixed at the exit of the fishway and the distance between the equipment and the exit was 7 meters. Hydroacoustic detection was conducted during day and night time. The results showed that a total of 11 fish species can swim through the passage, which are Pelteobagrus vachelli (Richardson), Rhinogobio typus Bleeker, Megalobrama amblycephala, Saurogobio dabryi Bleeker, Opsariicjthys bidens, Distoechodon tumirostris, Lepturichthys fimbriata (Gunther), Coreius heterodon (Bleeker), Siniperca chuatsi (Basilewsky), Hypophthalmichthys molitrix (Cuvier et Valenciennes) and Hemiculter leucisclus (Basilewsky), among which Pelteobagrus vachelli (Richardson), Hemiculter leucisclus (Basilewsky) and Distoechodon tumirostris are the main species. The quantity and weight of the fish caught was 37 individuals with a total weight of 2813.4g, among which the quantity and weight of Pelteobagrus vachelli (Richardson) accounted for forty-six percent and forty-one percent, respectively. The average length of the caught fish was 166.9mm and the 95% confidence interval was between 152.5mm and 181.3mm. The average weight of the caught fish was 80.0g and the 95% confidence interval was between 58.3g and 101.6g. Hydroacoustic equipment was used for 1267 minutes and 658 signals were detected. During the daytime, 571 signals were detected and the average target strength was -55.68dB. The equation of TS=23.902lgSL-87.3 was adopted to calculate the fish length and the average fish length in the daytime was 33.32cm. The 87 signals in the nighttime were also calculated; the average target strength and fish length were -54.48dB and 34.62 cm, respectively. The fish quantity detected in the nighttime was lower than in the daytime, but the target strength and the average fish length in the nighttime was a little higher. The average length of the detected fish was 33.50cm and the 95% confidence interval was between 30.43cm and 36.55cm. According to our investigation, Cuijiaying fishway offers an exchange channel for fish below and up the dam site in the detected period and protects the fishery resource in the river basin.
Number of references:30
Main heading:Fish
Controlled terms:Equipment - Fisheries - Fishways - Natural resources - Navigation - Power generation
Uncontrolled terms:Confidence interval - Cuijiaying - Effect - Fishery resources - Hanjiang rivers - Hydroacoustic equipment - Target strength - Trammel net
Classification code:822 Food Technology - 821.3 Agricultural Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 716.3 Radio Systems and Equipment - 706 Electric Transmission and Distribution - 901 Engineering Profession - 512 Petroleum and Related Deposits - 471.5 Sea as Source of Minerals and Food - 471 Marine Science and Oceanography - 461 Bioengineering and Biology - 444 Water Resources - 501 Exploration and Prospecting
DOI:10.3969/j.issn.1002-6819.2013.03.025
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 30>
Accession number:20131416161871
Title:Segmentation and reconstruction of overlapped apple images based on convex hull
Authors:Song, Huaibo (1); Zhang, Chuandong (2); Pan, Jingpeng (1); Yin, Xu (1); Zhuang, Yibin (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest Agriculture and Forestry University, Yangling 712100, China; (2) Computer Science Department, Jining University, Jining 273155, China
Corresponding author:Song, H.(songyangfeifei@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:163-168
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The segmentation and localization of overlapped apples in nature scenes are the key factors for the efficiency of picking robot's. To achieve successful recognition of occluded apples on the basis of K-means color clustering algorithm, a convex hull based concave point detection algorithm is presented. K-means color clustering algorithm is used to detect the apples, in which the parameter K is 3 (that is, the image is clustered to 3 different kinds such as the apples, the leaves and branches). The depressed regions are obtained by subtracting the binary image from its convex hull image after applying the color-clustering algorithm. By using image opening algorithm, the regions that areas are less than half the biggest region are removed. The remained depressed regions are used to detect the point of intersection of overlapped apples, and then the concave point detection is transformed to salient point detection, which reduces the complexity of classical concave point detection algorithm. Some split criteria are given as: 1) The length of split line should be short; 2) The direction of the detected points should be opposite, which means that the detected points from the same region should not be used to split an object; 3) The split contours must be a major arc. By using these given criteria, the detected concave points are matched to realize the segmentation of overlapped apples. The overlapped apple regions are unable to use, and these parts are incompletely segmented. For these defectively segmented apples, the spline interpolation technique is used to reconstruct the apples: 1) The centroid of segmented region is used as the starting point and the points on the contour are transformed from orthogonal coordinate to polar coordinate; 2) Rearranging the point by the value of polar angles, from small to big; 3) The rearranged pole diameters are interpolated by using spline interpolation technique; 4) The original polar angels and interpolated polar diameters are retransformed from polar coordinate to orthogonal coordinate to get smoothed, complete contour of overlapped regions. To validate the effectiveness of the algorithm, 3 different kinds of simulating examples (2 overlapped objects, 3 overlapped objects and 5 overlapped objects) and 20 overlapped apples in nature scenes are tested, the average localization error is 14.15%, and the average overlap ratio is 85.08%. The experimental results show that the convex hull based occluded objects segmentation algorithm has preferable performance, and it is feasible and valid for overlapped apple segmentation in nature scenes.
Number of references:22
Main heading:Image segmentation
Controlled terms:Algorithms - Clustering algorithms - Color - Computational geometry - Fruits - Image reconstruction - Interpolation - Signal detection
Uncontrolled terms:Concave points - Convex hull - Orthogonal coordinates - Overlapped objects - Point detection algorithm - Point of intersections - Salient point detections - Spline interpolation
Classification code:821.4 Agricultural Products - 741.1 Light/Optics - 741 Light, Optics and Optical Devices - 921 Mathematics - 723.5 Computer Applications - 721 Computer Circuits and Logic Elements - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications
DOI:10.3969/j.issn.1002-6819.2013.03.022
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 31>
Accession number:20131416161855
Title:Finite element mode analysis and experiment of combine harvester chassis
Authors:Li, Yaoming (1); Sun, Pengpeng (1); Pang, Jing (1); Xu, Lizhang (1)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education and Jiangsu Province, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Li, Y.(ymli@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:38-46
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:With the rapid development of agricultural mechanization in China, the combine harvester has been applied widely in the past decade. Compared with foreign study, however, domestic studies of the vibration intensity as well as the whole anti-vibration performance of the combine harvester in the various operating conditions were still in its infancy. And few researches were focused on the vibration stability of combine harvester chassis frame, although which was the installed base of the combine harvester, not only carrying the cutter, conveyor, threshing and separating device, but also supporting the engine and other mechanism. During the combine harvester working, the exciting vibrations from the pavement, cutter, engine, vibrating screen and threshing cylinder would cause the combine harvester vibration. Once those excitation frequencies were closed to or overlapped the natural frequencies of the combine harvester chassis frame, the whole body of the combine harvester would produce resonance seriously, which brought about adverse effect on work performance, service life and reliability of the combine harvester. Therefore, in order to improve the operating performance and optimize the chassis structure of the combine harvester, it was particularly necessary to carry out the modal testing and analysis on the chassis frame of the combine harvester. In the paper, the parametric modeling of the combine harvester Julong-280 chassis frame was developed using the three-dimensional modeling software UG. After meshing, the modal parameters as well as the modal vibration shapes were calculated utilizing the NX Nastran, and the first 4 modal frequencies were 20.44, 36.35, 41.75 and 43.67 Hz, respectively. In order to verify the accuracy of the modal analysis results, the laboratory modal testing about the combine harvester JuLong-280 chassis frame was implemented by exciting vibration method with the DH5902 dynamic analysis system. Then experimental modal parameters were obtained, and the first 4 modal frequencies were 20.02, 38.82, 41.02 and 45.78 Hz, respectively. By comparing the above results, it could be seen that the theoretical modal frequencies were close to the experimental modal frequencies (the maximum error is 6.36%) and their mode shapes were also basically the same, which verified the correctness of the calculated results and the accuracy of the chassis frame finite element model. Then, the excitation frequencies of the exciting vibrations from the pavement as well as the engine, cutter bar, vibrating screen and threshing cylinder of the combine harvester were analyzed, and the result demonstrated that the natural frequencies of the combine harvester chassis frame were closed to or overlapped the above excitation frequencies, which implied the combine harvester was vulnerable to resonance in operation. Therefore, in order to improve the modal frequencies to avoid the resonance, a reasonable optimization proposal was conducted by the Altair HyperOpt method. The optimization results indicated that the first 4 modal frequencies of the improved frame increased respectively to 21.70, 36.61, 43.64 and 46.33 Hz with the weight of the frame increased by 3.77%. These values avoided the range of external excitation frequencies of the threshing cylinder 15-18.3 Hz as well as the engine 38.3-41.7 Hz, which means the improvement could avoid the resonance effectively.
Number of references:26
Main heading:Harvesters
Controlled terms:Agriculture - Chassis - Engine cylinders - Engines - Finite element method - Modal analysis - Natural frequencies - Optimization - Pavements - Structural panels - Three dimensional - Vibrating screens - Vibrations (mechanical)
Uncontrolled terms:Agricultural mechanization - Combine harvesters - Experimental modal parameters - External excitation frequency - Modal test - Optimization design - Three-dimensional modeling - Threshing and separating
Classification code:921 Mathematics - 902.1 Engineering Graphics - 821.1 Agricultural Machinery and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 711.1 Electromagnetic Waves in Different Media - 931.1 Mechanics - 663.2 Heavy Duty Motor Vehicle Components - 612 Engines - 605.1 Small Tools, Powered - 408.2 Structural Members and Shapes - 406.2 Roads and Streets - 612.1.1 Internal Combustion Engine Components
DOI:10.3969/j.issn.1002-6819.2013.03.006
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 32>
Accession number:20131416161859
Title:Numerical simulation and optimum design on airflow distribution chamber of air-impingement jet dryer
Authors:Dai, Jianwu (1); Xiao, Hongwei (1); Bai, Junwen (1); Zhang, Qian (1); Xie, Long (1); Gao, Zhenjiang (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Gao, Z.(zjgao@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:69-76
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The airflow distribution chamber is an important part of the air-impingement jet dryer. Non-uniform distribution of airflow field can cause inconsistence of materials quality, prolong the drying process and consume more energy. Therefore, it is essential to optimize the flow field structure. However, the traditional way of design-manufacture-further improvements requires long transformation time, high costs and the measurement range is usually disappointing. Computational Fluid Dynamics (CFD) can provide detailed information on airflow patterns and ensure convenient design of agricultural equipments. In this paper, the Computational Fluid Dynamics (CFD) was first used to simulate the inner flow of structures similar to airflow distribution chamber based on the differential equation and RNG k-Ε turbulence model. The original structure was a cuboid and the inlet boundary was set to velocity-inlet. The speed deviation ratio(E) and the non-uniformity coefficient(M) were chosen as comprehensive evaluation indicators. The velocity and pressure distributions in chamber flow field were obtained and used to analyze the improved designs based on the original structure. They were inclination models, semi-cylindrical models and flat vortex models. The simulation results indicated that two symmetrical reverse vortex zones were formed in original structure, which led to the nozzle exit velocity first decreases and then increases along the height direction. The airflow velocity of round nozzles ranged from 11.9 to 17.7 m/s under the design condition and the minimum value was got in the eighth row. The E and M values of original structure was calculated to be 24.6% and 18.1%, respectively. This illustrates that the original structure was far from perfect. Decreasing the width of chamber bottom could not improve the distribution of airflow field, while the spoiler models were proved feasible. The flat vortex models built a greater effect on the optimization of airflow distribution than semi-cylindrical models. And the E and M values of the flat models dramatically decreased. It maybe because several uniform vortex zones formed between flats, which had a positive impact on airflow distribution. The optimum solution was got under the flat vortex model with 160 mm and 14 mm as the value of the plate-to-plate distance and the height difference, respectively. Moreover, the airflow velocity merely ranged from 13.1 to 15.3 m/s. The distribution trend of simulation results showed little difference compared to the experiment data. The maximum relative error under different conditions changed from 4.2% to 8% showing an increasing trend as mass flow increased. The results provide a reference for the uniformity design of structures similar to the airflow distribution chamber.
Number of references:30
Main heading:Structural design
Controlled terms:Air - Computational fluid dynamics - Computer simulation - Differential equations - Dryers (equipment) - Flow fields - Nozzle design - Nozzles - Optimization - Plates (structural components) - Turbulence models - Velocity - Vortex flow
Uncontrolled terms:Agricultural equipment - Air impingement drying - Airflow distribution - Comprehensive evaluation - Flow field structure - Maximum relative errors - Non-uniform distribution - Optimum
Classification code:931.1 Mechanics - 921.5 Optimization Techniques - 921.2 Calculus - 804 Chemical Products Generally - 802.1 Chemical Plants and Equipment - 723.5 Computer Applications - 631.1 Fluid Flow, General - 408.2 Structural Members and Shapes - 408.1 Structural Design, General
DOI:10.3969/j.issn.1002-6819.2013.03.010
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 33>
Accession number:20131416161883
Title:Evaluation method of feature vector in vinegar identification by electronic nose
Authors:Yu, Huichun (1); Chu, Bing (1); Yin, Yong (1)
Author affiliation:(1) Department of Food and Bioengineering, Henan University of Science and Technology, Luoyang 471003, China
Corresponding author:Yin, Y.(yinyong08@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:258-264
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In a test of the electronic nose (E-nose), two evaluation methods of the feature vector identification ability are commonly used: 1) visual analysis for the discrimination result, 2) statistical computation for the correct rate of the discrimination result. However, when the correct rates of the discrimination result are same, for the different feature vectors, the identification ability can not be evaluated accurately and quantitatively by the above two methods. In order to achieve the precise evaluation of the feature vector identification ability, different kinds of vinegar were taken as the study object and tested by the E-nose. Six kinds of feature vectors including Variance (Var), Integral value (Inv), Average value in relative steady-state (Avrs), Value of area divided by the slope (Vads), Average differential value (Adv), and Wavelet energy value (Wev) were extracted from the acquisition data after removing the background signal. The correlation coefficient between feature vectors and categories was used as an evaluation index of the feature vector's identification ability, the evaluation and comparison for the feature vectors is achieved by this index. Absolute values of the correlation coefficient between feature vectors and categories are respectively 0.2936, 0.6455, 0.6182, 0.1027, 0.6176 and 0.6189. Among them the absolute value of correlation coefficient was least between the 'Vads' feature vector and the categories, and the absolute value of correlation coefficient was greatest between the 'Inv' feature vector and the categories. These results show that the identification ability of the 'Vads' feature vector is the lowest, and the identification ability of the 'Inv' feature vector is the highest. The correct rate of the Fisher discrimination result was calculated, and the classification effect graph of the Fisher Discrimination was analyzed for every feature vector. The correct rate of the 'Vads' feature vector was the lowest (39.2%). Its corresponding classification effect was the worst; all kinds of vinegar samples mixed, and the group centroids of three categories almost overlapped. The correct rates of the discrimination result were all 100% for the other feature vectors, so the comparison of feature vector identification ability can not be carried out only by the correct rates of discrimination. But the classification effect graphs of Fisher Discrimination for these feature vectors show that the clustering degree within and between the groups for the three categories of vinegar samples were very different, which indicates that there may still be differences among the feature vectors' identification ability, even though their discrimination correct rates were all 100%. Specifically, the classification effect of feature vector 'Inv' was the best, the clustering degree of samples within the groups was the highest, and the boundaries between groups were the most distinct. The discriminating results of Fisher Discrimination prove that the higher the feature vector identification ability is, the better the classification result is. This result is in accord with that of the absolute values of the correlation coefficient. Therefore, it is right and effective that the correlation coefficient between feature vectors and categories be used as an evaluation index of the feature vector identification ability. The proposed method will provide a new train of thought for studies of quantitative evaluation in the E-nose system.
Number of references:26
Main heading:Vectors
Controlled terms:Acetic acid - Correlation methods - Feature extraction - Identification (control systems)
Uncontrolled terms:Classification results - Correlation coefficient - Electronic NOSE - Electronic nose (e-nose) - Fisher discrimination - Quantitative evaluation - Statistical computations - Vinegar
Classification code:716 Telecommunication; Radar, Radio and Television - 731.1 Control Systems - 804.1 Organic Compounds - 921.1 Algebra - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2013.03.034
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 34>
Accession number:20131416161856
Title:Lightweight design of chassis frame for motor boom sprayer
Authors:Han, Hongyang (1); Chen, Shuren (1); Shao, Jingshi (2); Yao, Yong (2); Chen, Gang (1)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang 212013, China; (2) Jiangsu Yuantong Sporting Vehicles Co. Ltd., Zhenjiang, 212325, China
Corresponding author:Chen, S.(srchen@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:47-53
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Traditional optimization design ignores the effect of noise and design variables, which would make the objective function out of range, and excessive reliance on safety factor can also cause redundancy optimal design. Therefore, it is particularly important to set up design parameters properly in frame structure design stage, which can ensure the robustness of structure. With the development of computer technology and finite element theory, computer aided engineering technology is widely used in industries such as aerospace, automotive, and a large number of results have been achieved. The method which using advanced finite element software to analysis vehicle structure and integrating theoretical analysis and experimental results to perform optimal design for vehicle is becoming an important part for product development. YTT-1000 type of motor boom sprayer is a new type of boom sprayer, which is mainly used for orchard spraying and plant protection. In order to solve current problems that frame of motor boom sprayer are too heavy and fuel consumption ratio are exactly high, carbon emissions are too much and so on. A type of motor boom sprayer frame was studied in the paper, and the mesh generation software Hypermesh was used for its finite element modeling. Then the model was imported to Finite Element Analysis (short for FEA) software Radioss to do free modal analysis, the experimental modal analysis of frame were also carried out. Through modal analysis, natural frequency and mode of the frame was calculated, all these calculated results then were compared with experimental data, and the correctness of modal was verified. To calculate stress distribution and deformation of frame under bending condition and limited torsion condition, static analysis of frame were performed. The static analysis results showed that the max von mises stress under these two conditions were 182.5 and 204.5 MPa, which were still less than the specified value 235 MPa; the max displacement value were 2.97 and 4.42 mm, which were still less than the specified value 10 mm. Based on the results of FEA, a frame model of optimal design was established, and one more reasonable lightweight design proposal was made by calculating. The results showed that through the optimization, the weight of frame decreased 40.4% from 116kg to 69.1kg, and the lightweight objective was met basically. Besides, through the structure improvement, safety factor under bending condition increased 9.7% from 1.29 to 1.41, safety factor under limited torsion condition increased 7.8% from 1.15 to 1.24, and the max von mises stress under bending condition and limited torsion condition decreased by 8.9%(from 182.5 to 166.3 MPa) and 7.2%(from 204.5 to 189.7 MPa), respectively. The max displacement under these two conditions increased 9.8% and 5.2%, respectively. Although the max displacement was increased, these values still less than the specified value 10 mm. Given the complicated operating conditions of motor boom sprayer, and most of the frame structure damage was caused by fatigue failure. Therefore, a series of fatigue testing under random loading and fatigue failure analysis of frame will be carried out in the future. This study may provide a reference for enterprise to do research on motor boom sprayer.
Number of references:31
Main heading:Design
Controlled terms:Bending (deformation) - Computer aided engineering - Failure analysis - Fatigue damage - Fatigue testing - Finite element method - Light weight structures - Loading - Modal analysis - Optimal systems - Optimization - Product development - Safety factor - Soil structure interactions - Static analysis - Stress concentration - Structural frames - Torsional stress - Vehicles
Uncontrolled terms:Boom sprayer - Experimental modal analysis - Fatigue failure analysis - Finite element modeling - Finite element software - Finite element theories - Frame - Structure improvement
Classification code:921 Mathematics - 913.1 Production Engineering - 723.5 Computer Applications - 672 Naval Vessels - 483.2 Foundations - 432 Highway Transportation - 422.2 Strength of Building Materials : Test Methods - 421 Strength of Building Materials; Mechanical Properties - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.03.007
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 35>
Accession number:20131416161886
Title:Simulation by Aspen Plus on desolventizing of crude oil in soybean protein extracting process with reverse micelles
Authors:Wang, Xin (1); Yu, Guoping (1); Du, Chengliang (3); Wu, Zhiguang (4)
Author affiliation:(1) Food College, Northeast Agricultural University, Harbin 150030, China; (2) Heilongjiang Entry-Exit Inspection and Quarantine Bureau, Harbin 150001, China; (3) Heilongjiang Provincial Government Office, Harbin 150001, China; (4) Ministry of Education, Micro/Nanotechnology Research Centre, Harbin Institute of Technology, Harbin 150080, China
Corresponding author:Yu, G.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:279-284
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Compared with other traditional methods, the disadvantages of high production costs and pollution prevention were overcome in the soy-protein extraction process by reverse micelles. Soybean crude oil, containing organic solvent, can be extracted together with soybean protein by reverse micelles. It is necessary to control the purity of the organic solvent that is recycled, as well as the purity of the soybean crude oil in the circulating production process. The Aspen Plus 11.1 software is used for simulating the desolventizing of crude oil in the soy-protein extraction process by reverse micelles, which is aimed at recycling the organic solvent. This work aims to study continuous and circulating spirit distillation by computational simulation, presenting some strategies of process control to regulate the purity of the solvent and the soybean oil. With the modular analysis function of Aspen Plus, the purity of the oil and solvent, the stage number of distillation column, and the heat load of the reboiler and the condenser were analyzed. A generalized model (based on the NRTL model) for estimation of activity coefficients is applied to the simulation of the extraction process. The equilibrium stage model based on the RADFRAC module of Aspen Plus is employed for the steady-state simulation of the improved process flowsheet, and therefore rigorous simulations allow the appropriate operating conditions to be established in the separating process. It is shown in the results that the reflux ratio of the vacuum distillation was 0.352, the distillate flow was 10.348 kg/h, and the purity of the oil and solvent can be 98.9% and 99.7% respectively, while the actual heat loads of the reboiler and the condenser were 1398.824 W and -1626.226 W, respectively. According to the sensitivity analysis, the concentration of oil and solvent grew respectively with the number of stages, and the optimal number of stages was seven. The cost was analyzed based on simulation calculations, in which the annual cost savings was yuan 1272000. As an alternative to control the purity of solvent and soybean oil, the spirit distillation unit was highly efficient in the case of low contamination and production costs. Moreover, the reflux ratio and product flow rate have an important influence on the purity of spirit composition. The key parameters were provided for unit operations separating organic solvent from soybean oil. The technical key points for the industrialized installation design were discussed to provide reliable data for enlarged desolventizing devices in the industrial field.
Number of references:30
Main heading:Computer simulation
Controlled terms:Computer software - Costs - Crude oil - Design - Distillation - Distillation equipment - Extraction - Micelles - Oilseeds - Organic solvents - Processing - Proteins - Recycling - Solvents - Soybean oil - Thermal load
Uncontrolled terms:ASPEN PLUS - Computational simulation - Desolventizing - Equilibrium stage model - Pollution prevention - Simulation calculation - Soybean proteins - Steady-state simulations
Classification code:911 Cost and Value Engineering; Industrial Economics - 821.4 Agricultural Products - 804.1 Organic Compounds - 802.3 Chemical Operations - 801.3 Colloid Chemistry - 913.4 Manufacturing - 723.5 Computer Applications - 643.1 Space Heating - 523 Liquid Fuels - 452.3 Industrial Wastes - 408 Structural Design - 723 Computer Software, Data Handling and Applications
DOI:10.3969/j.issn.1002-6819.2013.03.037
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 36>
Accession number:20131416161860
Title:Numerical simulation on gas-liquid two-phase flow of self-priming pump during starting period
Authors:Li, Hong (1); Xu, Dehuai (1); Tu, Qin (1); Cheng, Jun (1); Li, Lei (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Li, H.(hli@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:77-83
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Self-priming pump is a kind of special centrifugal pump, which is widely used in irrigation and drainage, construction, mine drainage, city fire fighting, military, petrochemical industry, food industry and so on. The self-priming pumps produced in China have some problems such as complex structure, large size, difficulty for casting, low suction height, long self-priming time, and the design methods of the self-priming pump have still stayed in the semi-empirical theories stage, which can not meet the demand of predicting properties and the requirement of new products design. In order to know the flow rule, it becomes very important to research the inner flow of the self-priming pump. The self-priming transient process in self-priming pump is complex gas-liquid two-phase flow, gas-liquid mixing and separation performances play a crucial role during self-priming process. The self-priming pump typed 65ZB-40C was chosen as the numerical model. The three-dimensional model was generated in Pro/E software, and the three-dimensional unstructured grid was adopted in meshing in ICEM software because of the complexity of the geometric model. The gas-liquid two-phase flow field in a self-priming pump was simulated in FLUENT software by using VOF multiphase model, sliding mesh, and combined with the rotational speed curve of the impeller and the pressure curve of the pump outlet from tests. The PISO algorithm was used to handle the pressure-velocity coupling, and governing equations were discrete with second order upstream scheme. The model was initialized before computing, set the lower part of the pump for water, and the rest of the pump for air. Gas-liquid mixing and separation phenomena were simulated and the air volume fraction curves during starting period were obtained from monitoring points on the gas-liquid separation chamber inlet, the reflux hole, the cross-sections of volute and impeller. Results show that a gas-liquid mixing layer appeared at the outer edge of the impeller after running, the phenomena of gas-liquid mixing and separation is obviously at the gas-liquid separation chamber inlet, the air volume fraction curve of the gas-liquid separation chamber inlet fluctuated strongly due to the unstable operation at the early stage of the starting period, the air volume fraction curve of the impeller fluctuated strongly due to the bubbles constantly generating and breaking. The results suggest that this approach is good in simulating the gas-liquid two-phase flow of the self-priming pump during starting period. It plays an important role in the further study of gas-liquid mixing and separation phenomenon in the self-priming pump.
Number of references:27
Main heading:Liquids
Controlled terms:Centrifugal pumps - Computer simulation - Gases - Impellers - Mixing - Product design - Pumps - Software testing - Three dimensional - Two phase flow - Volume fraction
Uncontrolled terms:Air volumes - Gas liquids - Gas-liquid two-phase flow - Pressure-velocity coupling - Self-priming - Separation performance - Starting periods - Three-dimensional model
Classification code:913.1 Production Engineering - 802.3 Chemical Operations - 723.5 Computer Applications - 931.2 Physical Properties of Gases, Liquids and Solids - 641.1 Thermodynamics - 618.2 Pumps - 601.2 Machine Components - 631.1 Fluid Flow, General
DOI:10.3969/j.issn.1002-6819.2013.03.011
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 37>
Accession number:20131416161863
Title:Interpreting method of regional soil salinity 3D distribution based on inverse distance weighting
Authors:Wu, Yakun (1); Liu, Guangming (2); Yang, Jinsong (2); Yu, Shipeng (2)
Author affiliation:(1) Anhui University of Technology, Institute of Civil Engineering and Architecture, Maanshan 243002, China; (2) Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
Corresponding author:Liu, G.(gmliu@issas.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:100-106
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to clarify the three-dimensional spatial pattern of soil salinity on a regional scale, the Inverse Distance Weighting (IDW) method was used, combining the electromagnetic induction technique in this study. Apparent electrical conductivities were measured by electromagnetic induction, and thus layered salinity interpreting models with reasonable accuracy were established. The models showed a significant correlation between soil salt contents of different layers and apparent soil conductivities measured by electromagnetic induction, while soil moisture and clay content also significantly correlated with the apparent soil electrical conductivities. According to the classical statistical results, the minimum values (0.742-0.821 g/kg) of soil salt contents in different soil layers were substantially equal, but the maximum values differed from 5.943 to 9.810 g/kg, showing a significantly increased regularity with increasing depth, and the average values varied from 2.3 to 3.0 g/kg. Soil salinities of every layer belonged to moderate variability while the coefficients of variation increased with the increase of soil depth. Three-dimensional spatial distribution of soil salinity was characterized by IDW. Regional soil salinity spatial distribution characteristics were intuitively revealed by three-dimensional graphics. Profile soil salinity varied greatly with depth, showing different types of profile distribution characteristics in different locations across the study area. Soil of the main study area registered moderate or severe degree of salinization, which showed that there were more common and severe soil salinization in this study area. The 3D inverse distance weighting method combined apparent soil conductivity rapid determination by means of electromagnetic induction, and could achieve exact analytical evaluation of the three-dimensional spatial variability of regional soil salinity. This study and the results could provide a reliable technical method for interpretation and evaluation of regional soil salinity in the three-dimensional spatial distribution characteristics.
Number of references:32
Main heading:Geologic models
Controlled terms:Electric conductivity - Electromagnetic induction - Salinity measurement - Soil moisture - Soils - Spatial distribution - Three dimensional - Three dimensional computer graphics
Uncontrolled terms:Apparent electrical conductivity - Apparent soil electrical conductivities - Electromagnetic induction technique - Inverse distance weighting - Inverse distance weighting method - Regional scale - Spatial variability - Three-dimensional graphics
Classification code:481.1 Geology - 483.1 Soils and Soil Mechanics - 701.1 Electricity: Basic Concepts and Phenomena - 723.5 Computer Applications - 902.1 Engineering Graphics - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2013.03.014
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.
<RECORD 38>
Accession number:20131416161850
Title:Effects of land consolidation in plains and hills on plots use
Authors:Zhang, Zhengfeng (1); Yang, Hong (2); Gu, Xiaokun (3)
Author affiliation:(1) School of Public Administration, Renmin University of China, Beijing 100872, China; (2) China Land Consolidation and Rehabilitation, Beijing 100035, China; (3) College of Tourism and City Management, Zhejiang Gongshang University, Hangzhou 310018, China
Corresponding author:Zhang, Z.(zhengfengzh@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:3
Issue date:February 1, 2013
Publication year:2013
Pages:1-8
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The implementation of various engineering measures have an impact on plots in the land consolidation areas. Quantitative assessment of the effect of land consolidation on plots not only can improve the land consolidation theory, but also can provide a basis for the optimization of planning design for land consolidation projects. In this paper, land consolidation affected plots are examined from four aspects, including plot scale, plot shape, plot space and plot farming efficiency. We selected a land consolidation project in Maoshi Town of Jianli County in Hubei Province, and a land consolidation project for a low hill area in Lanjiagang Village in Laohe City of Hubei Province as typical representatives of plain and hill land consolidation projects, respectively. Quantitative assessment of the effect of land consolidation in the two areas on plots, and comparison analysis was conducted. The results showed that the land consolidation had similar effects on plots in the two project regions. The results indicated as follows: (1) The plot size was expanded, the small-scale plots merged, and the plots were relatively uniform after consolidation. The average plot size in the plain land consolidation project increased from 5.82 to 7.28 hm<sup>2</sup>, and that in the hill land consolidation project increased from 2.75 to 5.13 hm<sup>2</sup>. (2) The shape of the plots were more regular through division, the geometry similarities of plots were enhanced, and the interference of human on the land increased after consolidation. The plot shape index in the plain land consolidation project decreased from 1.2381 to 1.1924, and that in the hill land consolidation project decreased from 1.4519 to 1.4496. The fractal dimension in the plain land consolidation project decreased from 1.0568 to 1.0479, and that in the hill land consolidation project decreased from 1.0572 to 1.0567. (3) The plots transformed from discrete small plots with a high number before consolidation into highly-connected large plots with a low number after consolidation increased, and the plots tended to concentrate distribution. (4) The plot farming efficiency increased after consolidation. The average farming time in the plain land consolidation project decreased from 57 to 45 min/hm<sup>2</sup>, and that in the plain land consolidation project decreased from 62 to 48 min/hm<sup>2</sup>.
Number of references:30
Main heading:Landforms
Controlled terms:Consolidation - Efficiency - Fractal dimension - Land use - Spatial distribution
Uncontrolled terms:Comparison analysis - Engineering measures - Hubei Province - Land consolidations - Planning designs - Quantitative assessments - Scale - Shape
Classification code:403 Urban and Regional Planning and Development - 481.1 Geology - 483 Soil Mechanics and Foundations - 913.1 Production Engineering - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2013.03.001
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.