<RECORD 1>
Accession number:20150400457744
Title:Determination of nitrogen release from slow and controlled-release fertilizers by Dumas process using TOC/TN analyzer
Authors:Li, Guihua (1); L, Zigu (1); Bao, Wankui (1); Wen, Yunjie (1); An, Yongpeng (1); Liu, Yunxia (1); Han, Ya (1); Wang, Hong (1)
Author affiliation:(1) National Engineering Laboratory for Improving Quality of Arable Land/Key Laboratory of Plant Nutrition and Fertilizer, Ministry of Agriculture/Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing, China
Corresponding author:Wang, Hong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:275-280
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Kjeldahl distillation-titration method (KDTM) is a standard method used by most laboratories to measure total nitrogen (N) in the Kjeldahl digests of fertilizer samples. However, the KDTM procedure generally is labor intensive and time-consuming for sample digestion process, in which concentrated acids and poisonous gas have a negative impact on the environment and health of laboratory operators. The purpose of this article was to investigate whether the methods of Dumas process (total organic carbon/total nitrogen analyzer, TOC/TN analyzer) can be used to determine N contents in the release solutions from slow/controlled release nitrogen fertilizers (S/CRNFs). Two kinds of S/CRFs with 43.2% and 37.3% of total N content were selected. The solutions containing 10% of S/CRNFs were collected after incubating at 25 for 1, 3, 7, 14 and 28 days, respectively. In the TOC/TN analyzer, the solution samples diluted 400 times were oxidized in the combustion tube in the presence of oxygen at high temperature (800) using Pt as catalyst. We compared the N values measured by Dumas method and KDTM procedure. The result showed that a linear relationship can best describe the measured N concentration generated by both methods: y (Dumas-N)=0.905 x(Kjeldahl-N) 0.040.The Pearson's correlation coefficient was 0.991 with a significance level (n=30, P<0.01). Paired samples t-test indicated that there was no significant (P > 0.05) difference of the N release contents of the S/CRFs measured by TOC/TN analyzer and KDTM method. Cumulative N release rates of two fertilizers after incubating for 14 and 28 days determined by TOC/TN analyzer were higher than that by KDTM method. However, a positive linear correlation with r=0.997 (n=30, P<0.01) was verified between the two methods. The regression equation was y (TOC/TN analyzer)=0.908x (KDTM method) 0.818.Thus the results suggested that measured N release of S/CRNFs by TOC/TN analyzer agreed very well with that measured by KDTM method. The N release period is an important parameter for assessing the quality of the S/CRNFs. The relative percentage difference of the N release periods of the S/CRNFs was less than 20% between the two N determination methods, which was the acceptance criteria for evaluating the N release period with the national standards "GB/T 23348 -2009 slow-release fertilizer" and the chemical industry standard "HG/T 4215-2011 controlled-release fertilizers". It is suggested that the TOC/TN analyzer according to Dumas principle can be an alternative to the labor-intensive and time-consuming KDTM procedure for measuring N release of S/CRNFs. The TOC/TN analyzer is easy to handle and no preparation of sample digestion for N analysis is necessary. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Nitrogen fertilizers
Controlled terms:Chemical industry - Correlation methods - Distillation - Fertilizers - Nitrogen - Nutrients - Organic carbon - Titration
Uncontrolled terms:Dumas method - Kjeldahl - Nitrogen release - Slow/controlled release - TOC/TN analyzer
Classification code:801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 805 Chemical Engineering, General - 821.2 Agricultural Chemicals - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.23.035
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 2>
Accession number:20150400457743
Title:Toluene reforming by carbon dioxide recycled from biomass gasification into syngas production under microwave irradiation
Authors:Li, Longzhi (1); Song, Zhanlong (2); Ma, Chunyuan (2); Wang, Fumao (1); Tian, Yuanyu (3)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Shandong University of Science and Technology, Qingdao, China; (2) National Engineering Laboratory for Coal Combustion Pollutants Reduction, Shandong University, Jinan, China; (3) College of Chemical and Environmental Engineering, Shandong University of Science and Technology, Qingdao, China
Corresponding author:Song, Zhanlong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:268-274
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The quality of gaseous products can be deteriorated by tar, CO<inf>2</inf> and other impurities during the process of biomass gasification. Based on the those impurities analysis, tar conversion by CO<inf>2</inf> is performed in this paper. Toluene was chosen as a model compound in this study, and it was used for converting into syngas production over a biomass-derived char. Biomass char is obtained from the pyrolysis of corn straw at a microwave-assisted experimental system. The influences of heating method includes microwave heating (MH) and electrical heating (EH) as well as CO<inf>2</inf> flow rate on toluene conversion, syngas yield and carbon loss. The results show that toluene conversion from microwave heating is significantly higher than that from electrical heating under the same circumstances. And it is revealed that a maximum difference of toluene conversion between microwave heating and electrical heating is reached up to 15.58% at CO<inf>2</inf> flow rate of 80 mL/min. When a certain amount of CO<inf>2</inf> is imported, toluene conversion can be improved effectively. The highest toluene conversion of 93. 73% is achieved under microwave heating at CO<inf>2</inf> flow rate of 80 mL/min, while toluene conversion under electrical heating is reached a peak of 82.13%, corresponding to CO<inf>2</inf> flow rate of 40 mL/min. Moreover, the introduction of CO<inf>2</inf> can regulate the conversion of toluene into syngas production with a suitable ratio of H<inf>2</inf> and CO. At the same time, an excess of CO<inf>2</inf> can result in a loss of carbon contained in biomass-derived char. The carbon consumed through the gasification of CO<inf>2</inf> can be converted into part of syngas production, which can impose a direct contribution to total syngas yield. With the increase of CO<inf>2</inf> flow rate, a higher syngas yield from carbon consumption is achieved. The maximum contribution of carbon consumption to syngas yield is 15.40% under microwave heating at CO<inf>2</inf> flow rate of 120 mL/min. According to the results, it is found that the highest yield of syngas derived from toluene reforming by CO<inf>2</inf> under microwave heating is 173. 66 mL/min when CO<inf>2</inf> flow rate is 80 mL/min. And the yield mentioned above is 5.68 times that of syngas obtained from toluene cracking in the absence of CO<inf>2</inf>. A decrease in the conversion of toluene cracking is revealed, with the advancement of cracking experiment. And continuous decrease in toluene conversion occurred in cracking experiment until the conversion of toluene cracking drops below 49.0%. Afterwards, a stable phase of toluene conversion is seen in toluene cracking. It is fond that the conversion obtained from toluene reforming is maintained at a higher level, compared to that from toluene cracking. After toluene reforming conducted for 140 min, a decrease in toluene conversion is emerged. At the same time, a gentle decrease in the yield of syngas produced from toluene reforming is observed after 140 min. The conclusions of this study have a significant effect on efficient disposal and utilization of tar from biomass gasification. This research can also provide beneficial reference to the emission of CO<inf>2</inf>. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:15
Main heading:Carbon dioxide
Controlled terms:Biomass - Carbon - Cracks - Electric heating - Flow rate - Gasification - Heating - Microwave heating - Microwave irradiation - Microwaves - Reforming reactions - Synthesis gas - Tar - Toluene
Uncontrolled terms:Biomass char - Biomass Gasification - Carbon consumption - Conversion of toluene - Electrical heating - Experimental system - Syn-gas - Toluene conversion
Classification code:421 Strength of Building Materials; Mechanical Properties - 525.1 Energy Resources and Renewable Energy Issues - 631 Fluid Flow - 643.1 Space Heating - 704.2 Electric Equipment - 711 Electromagnetic Waves - 711.1 Electromagnetic Waves in Different Media - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804 Chemical Products Generally
DOI:10.3969/j.issn.1002-6819.2014.23.034
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 3>
Accession number:20150400457727
Title:Effect of hedgerow patterns controlling nitrogen loss of slope farmland in purple soil area
Authors:Pu, Yulin (1); Xie, Deti (2); Lin, Chaowen (3); Ni, Jiupai (2); Wei, Chaofu (2)
Author affiliation:(1) College of Resources and Environment, Sichuan Agricultural University, Chengdu, China; (2) College of Resources and Environment, Southwest University, Chongqing, China; (3) Soil and Fertilizer Institute, Sichuan Academy of Agricultural Sciences, Chengdu, China
Corresponding author:Xie, Deti
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:138-147
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural non-point source nitrogen is one of the major sources for surface water eutrophication in the world. Hedgerows have been widely used as a measure of controlling soil, water and nutrient losses. However, there are few studies on nitrogen concentration loading and composition in runoff under long period hedgerow patterns in purple soil area of southwest China. Field experiments were carried out for three years to examine effects of 13-year hedgerow intercropping patterns for controlling nitrogen loss. There were six treatments: contour cropping (T1), Amorpha hedgerow plus contour cropping (T2), and Vetiver hedgerow plus contour cropping (T3) on 20° slope land, and contour cropping (T4), alfalfa hedgerow plus contour cropping (T5) and Eulaliopsis binata hedgerow plus contour cropping (T6) on 13° slope land. Results showed that in general, hedgerow patterns can reduce total nitrogen concentration and different forms of nitrogen in runoff. In terms of total N, compared with T1, average total nitrogen concentration in runoff decreased by 36.0%, 33.0% for T2 and T3 on the 20° slope farmland, respectively. Compared with T4, average total nitrogen concentration in runoff decreased by 5.9% for T5, and it had no significant decrease for T6 (P>0.05) on the 13° slope farmland. Enrichment rate of sediment nitrogen for hedgerow patterns was higher (P<0.05) than that of the contour cropping treatment. This indicated that hedgerow patterns can effectively control sediment nitrogen loss. Hedgerow patterns reduced total nitrogen and different form of nitrogen loss from slope farmland. In terms of total nitrogen, compared with T1, annual average total nitrogen loss under T2 and T3 was respectively reduced by 32.86 and 31.99 kg/hm<sup>2</sup> accounting for 92.4% and 90.0% nitrogen loss reduction on the 20° slope farmland. Compared with T4, annual average total nitrogen loss under T5 and T6 was respectively reduced by 27.55 and 26.04 kg/hm<sup>2</sup> accounting for 88.7% and 83.9% in nitrogen loss reduction on the 13° slope farmland. Therefore, Amorpha, Vetiver, alfalfa and Eulaliopsis binata hedgerow patterns can be used for controlling agricultural non-point pollution in purple soil area. Effects of different hedgerow patterns on controlling nitrogen loss were difference. On same slope, effects of Amorpha patterns controlling nitrogen loss was better than that of Vetiver, and effects of Alfalfa patterns controlling nitrogen loss was better than that of Eulaliopsis Binata. Effects of hedgerow patterns in controlling nitrogen loss increased with the increase in slope degree. Overall, shrub hedgerow patterns can be used to control nitrogen loss in runoff under 20° slope farmland. More research is still needed when slope is larger than 20° slope. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Nitrogen
Controlled terms:Agricultural runoff - Agriculture - Eutrophication - Farms - Loading - River pollution - Runoff - Soil pollution - Soils - Surface waters - Water pollution - Wooden fences
Uncontrolled terms:Effects - Hedgerow patterns - Nitrogen loss - Purple soils - Slope farmland
Classification code:415.3 Wood Structural Materials - 444.1 Surface Water - 453 Water Pollution - 453.1 Water Pollution Sources - 483.1 Soils and Soil Mechanics - 672 Naval Vessels - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes
DOI:10.3969/j.issn.1002-6819.2014.23.018
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 4>
Accession number:20150400457722
Title:Numerical analysis for effects of concentration and diameter of sediment on solid-liquid two-phase flow in hydraulic turbine runner
Authors:Zhang, Guang (1); Wei, Xianzhu (1)
Author affiliation:(1) Harbin Institute of Large Electrical Machinery, State Key Laboratory of Hydropower Equipment, Harbin, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:94-100
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Sediment erosion of hydraulic turbine is the complicated engineering problem related to such factors as operating conditions of hydraulic turbine, solid-liquid two-phase flow characteristics and sediment properties. In this paper, the three dimensional full channel geometric model of prototype turbine is established to understand change in internal pressure of runner and sediment distribution in runner channel under different sediment flow conditions. The hydraulic turbine mainly consists of spiral case, vane, runner and draft tube. Every part generates its corresponding independent meshes, and then is connected with each other by internal interfaces. The total number of grid cell is 7 888 784 in computational domain. Considering solid-liquid interactions fully, based on Eulerian-Eulerian multiphase flow model, Reynolds-averaged Navier-Stokes and RNG k-Ε turbulence equations are numerically solved to study internal flows of hydraulic turbine runner under different sediment flow conditions. Research results show that pressure distributions on runner blade surfaces are similar under clear and sandy water flow conditions, i. e., from blade inlet to outlet edges, pressure gradually decreases, and there is a uniform transition without obvious local distortion in pressure field, but the surface pressure is slightly higher in the case of sediment flow. It is further found that surface pressure increases linearly with sediment concentration, and first increases and then decreases with the increase of sediment particle size. Sediment concentration is low on the pressure surface of blade near inlet edge, gradually increases towards the edge and attains its maximum value on the edge. Solid-liquid two-phase flow speed is high and blade thickness is small near outlet edge, so erosion destruction is easy to occur there. Under the conditions of the same sediment particle size, change in sediment concentration has little effect on sediment distribution on blade surface. Also, under the conditions of the same sediment concentration, small sediment particles evenly distribute on runner surface with low concentration, and large ones are clustered in the regions of blade leading and outlet edges to cause local serious erosion of runner blades. Finally, velocity difference between solid and liquid phases is discussed to analyze reasons for change in sediment distribution on blade surface in this paper. The results show that as far as this study is concerned, with the increase in sediment concentration, velocity difference changes a little under the conditions of the same sediment particle size. In this case, the solid-liquid two-phase flow structure is maintained, and pressure distribution is basically the same on blade surface. On the other hand, with the increase of sediment particle size, velocity difference gradually increases under the conditions of the same sediment concentration. The ability of sediment particle to follow water movement becomes bad, which makes sediment particle easily deviate from water streamline under the conditions of large-size sediment flow. Flow separation occurs in the flow direction and the regions where flow velocity changes significantly, and sediment particles hit blade surface to cause serious erosion of blade surface material. This study can provide technical references for the sediment control design of turbine runner operating in sediment-laden rivers. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:14
Main heading:Two phase flow
Controlled terms:Erosion - Flow of water - Flow separation - Flow velocity - Hydraulic motors - Hydraulic turbines - Impellers - Inlet flow - Liquids - Navier Stokes equations - Numerical analysis - Particle size - Pressure distribution - Sedimentation - Sediments - Velocity
Uncontrolled terms:Computational domains - Reynolds - Averaged Navier-Stokes - Sediment concentration - Sediment distribution - Sediment erosion - Sediment particle size - Solid-liquid interaction - Solid-liquid two phase flows
Classification code:483 Soil Mechanics and Foundations - 601.2 Machine Components - 617 Turbines and Steam Turbines - 617.1 Hydraulic Turbines - 631 Fluid Flow - 632.2 Hydraulic Equipment and Machinery - 802.3 Chemical Operations - 921.6 Numerical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2014.23.013
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 5>
Accession number:20150400457738
Title:Research and design of technology for tracking and positioning wild stocking animals
Authors:Lei, Hongzhou (1); Yang, Lu (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing, China
Corresponding author:Yang, Lu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:232-237
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Wild stocking animals become a trend as the animals activate a lot and their meat are delicious. But the stocking animals are often lost which leads to increase cost in farming. Therefore, it is very important to research on positioning technology, which is essential for wild stocking animal management. Although the mature satellite positioning technology - GPS, Compass, Wi-Fi positioning (cell network, WLAN and wireless sensor network-assisted positioning system) and wildlife radio-tracking technology can be applied in positioning, but it is extremely difficult to track the wild stocking animals because of the complex geographical environment the animals active, the affordability of farmers and other affecting factors. Combined with GPS positioning and wireless mobile cell network positioning technology, this study researches on the positioning technology of pseudo-cellular wireless mobile network for locating and tracking wild animals. Pseudo-cellular base station location, PCBSL for short, is a mobile communications network based on the principle of a positioning radiolocation and tracking technology, different from wireless mobile communications cellular network positioning, which is a direct application of mobile communication network positioning technology. In the technology of mobile communication, to determine the location of a mobile terminal in the network, it is calculated by the relative position of the device with the different base stations. The position of mobile terminals is determined through base station. The base station divided the whole communication area into many individual cells, the diameter of each cell ranged from tens of meters to thousands of meters mobie terminals actually get online through one of these cells, and then transfer data (voice, text, or multimedia data) via internet. Therefore, when a mobile terminal communicates in the internet, it is always connected to one of the cells, so the position of the mobile terminal can be determined by which cell it connected to the base station. Pseudo wireless mobile cellular network is similar in principle to build the base station network with base station as the core. The whole system consists of base station and mobile beacon and the composition is much simpler than mobile communication network. In PCBSL system, the main function of BS is to position RB and data forwarding. RB is a mobile device carried by livestock which could emit positioning signals. There are two kinds of PCBSL positioning: Single base station location which relies on a single base station, and Multi- station location, which uses multiple base stations to cooperate. The former achieves coarse positioning of beacons, of which the algorithm is similar to the TOA/TDOA algorithm of GSM. The latter can achieve relatively accurate positioning of beacons, of which there are AHLos algorithm, RADAR algorithm, the centroid algorithm, DV-HOP algorithm, APIT algorithm, MAP algorithm and so on, or the improved algorithms of them. When precise geographic information is needed, then GPS or Beidou system is invoked to provide more accurate location data. In order to adapt to the complex geographical environment, using functions like intelligent power management and remote device settings to control continuous work of devices, which reduces the complexity and high cost from simple GPS and meets the positioning demand of wild livestock stocking. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:12
Main heading:Mobile telecommunication systems
Controlled terms:Agriculture - Algorithms - Animals - Base stations - Cells - Cellular telephone systems - Complex networks - Computer terminals - Cytology - Global positioning system - Global system for mobile communications - Internet - Location - Mobile devices - Mobile phones - Radio navigation - Telecommunication networks - Tracking (position) - Wi-Fi - Wireless networks - Wireless sensor networks
Uncontrolled terms:Cellular base stations - Geographical environment - Mobile communication networks - Multi-base station - Positioning technologies - Wild grazing - Wireless mobile communications - Wireless mobile networks
Classification code:461.2 Biological Materials and Tissue Engineering - 716 Telecommunication; Radar, Radio and Television - 718.1 Telephone Systems and Equipment - 722 Computer Systems and Equipment - 722.2 Computer Peripheral Equipment - 723 Computer Software, Data Handling and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911 Cost and Value Engineering; Industrial Economics - 912 Industrial Engineering and Management - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.23.029
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 6>
Accession number:20150400457736
Title:Method for supervising and assessing eco-environment of organic food production bases based on high-resolution remote sensing data
Authors:Gao, Yanhua (1); Zhou, Xu (3); Shen, Wenming (1); Xiao, Tong (1); Qu, Ran (1); Wang, Hongliang (4)
Author affiliation:(1) Satellite Environment Center, Ministry of Environment Protection, Beijing, China; (2) Key Laboratory of Satellite Environment Remote Sensing, Ministry of Environment Protection, Beijing, China; (3) National Geomatics Center of China, Beijing, China; (4) College of Geoscience and Surveying Engineering, China University of Mining and Technology, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:215-223
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Organic agriculture is an ecological production management system that promotes and enhances biodiversity, biological cycles, and soil biological activity. It is based on the minimal use of off-farm inputs and management practices that restore, maintain, and enhance ecological harmony. The benefits of organic farming include reducing chemical input and loss of land, enhancing food security, rural development, sustainable livelihoods, and environmental integrity. Organic food is produced by farmers who emphasize the use of renewable resources and the conservation of soil and water to enhance environmental quality for future generations. Organic meat, poultry, eggs, and dairy products come from animals that are given no antibiotics or growth hormones. Organic food is produced without using most conventional pesticides, fertilizers made with synthetic ingredients or sewage sludge, bioengineering, or ionizing radiation. The development of organic food production bases is the effective measure to protect eco-environment, reduce agricultural non-point source pollution, recover agroecosystem health, and is the important way to ensure food security. However, with the development of the organic food production bases, there is a pressing need for a supervision system in environmental protection department. The application's method and technique process for the supervision of organic food production bases in China are currently expected to be established and perfecedt further. It is significant to establish the method and technique process for the supervision of organic food production bases. This paper researches the method for monitoring the eco-environment in organic food production bases and its buffer areaa based on high-resolution remote sensing data, and introduces the model and method for evaluating the risks facing organic food production bases. Firstly, according to The National Organic Food Standards and appraisal management provisions for organic food production bases, the objectives to be supervised in organic food production bases are different from those in its buffer areas. So, the classification system for organic food production bases was established to describe the spatial pattern of organic food production bases and its buffer areas. Significantly, the classification in organic food production bases is different from its buffer areas. Secondly, the monitoring index system which was derived from the classification data was established to achieve a deeper level of assessment on the condition and the risk source of the organic food production bases. Then, in order to determine the level of risk, the model and method for risk assessment of organic food production bases was established. The organic food production bases risk index (OFBRI) was calculated based on the main monitoring index. Five-level risk assessment was used to differentiate risk degree, and the evaluation criteria of risk levels are introduced. Finally, the technique process is applied to monitor the eco-environment and risks source of one of organic food production base in Jilin province. After the actual application, this method has been proven with satisfactory results on technical features and functional obtained. It can enlarge the range of application of this method to various organic food production bases. The method and technique process for supervision of organic food production bases can provide technical support for check and review the requirement of organic food production bases. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:9
Main heading:Chemical contamination
Controlled terms:Agriculture - Bioactivity - Biodiversity - Ecology - Environmental protection - Food supply - Ionizing radiation - Monitoring - Plant management - Regional planning - Remote sensing - Risk assessment - Sewage sludge - Soil conservation
Uncontrolled terms:Agricultural non-point source pollutions - Eco-environments - Environmental protection departments - High resolution remote sensing - Organic foods - Risk sources - Soil biological activity - Supervision
Classification code:403.2 Regional Planning and Development - 452.2 Sewage Treatment - 454 Environmental Engineering - 461 Bioengineering and Biology - 461.6 Medicine and Pharmacology - 711 Electromagnetic Waves - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3 Agricultural Methods - 822.3 Food Products - 912.2 Management - 922.1 Probability Theory - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.23.027
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 7>
Accession number:20150400457748
Title:Classification of pork comprehensive quality based on partial least squares projection and Vis/NIR spectroscopy
Authors:Liu, Yuanyuan (1); Peng, Yankun (1); Wang, Wenxiu (1); Zhang, Leilei (1)
Author affiliation:(1) College of Engineering, China Agricultural University, National R&D Centre for Agro-Processing Equipments, Beijing, China; (2) College of Mechanic and Electrical Engineering, Tarim University, Alar, China
Corresponding author:Peng, Yankun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:306-313
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pale, soft, and exudative (PSE) and dark, firm, and dry (DFD) are degraded grades of pork. Reddish- pink, firm, and non-exudative (RFN) are considered superior grades of pork. The meat color, pH value, and water holding capacity for PSE, DFD, and RFN have different ranges which directly influence the purchasing decision of customers, thus affecting the economic benefits of the pork processors. With growing demand for quality meat and increasing state-of the-art meat processing technologies, pork industries are in need of a reliable technology for rapid, accurate, and non-destructive detection of meat quality. Spectral technology has gained importance in agricultural research and the meat industry. Spectral technology has also shown its massive potential in the meat industry. However, full wave band contains huge amount of spectral information, which possess a severe drawback to spectroscopic technology in terms of its accuracy and detection speed. This study proposes a pork comprehensive quality classifying method based on partial least squares (PLS) projection algorithm and support vector machine (SVM). The acquired spectral data of sample meat were first normalized using standard normal variation (SNV) transformation method. Next, the whole sample was randomly classified into two sets: the calibration set (for developing prediction model using 75% of total samples) and the validation set (to validate the model using remaining 25% of the total samples). Mean filter was used to smooth the normalized spectral signal. Partial least square projection method was then used to obtain projection coefficients for each wave band. Classification models were developed using 1 to 20 different wave bands, and root mean square errors (RMSE) of each model were calculated by cross validation. The lowest RMSE was obtained using 13 wave bands and it was observed that it became stable with more wavelengths. The spectral wave lengths of 371, 388, 425, 456, 473, 562, 578, 607, 696, 764, 772, 813 and 927 nm were chosen based on the RMSE value to develop a pork quality prediction and classification model. Particle swarm optimization (PSO) algorithm optimized penalty parameter and radial basis core function parameter, was 4. 939 and 0.01 for the best. Pork comprehensive quality SVM classifier was established using special wavelengths and optimized parameters. It was shown that the back-to-recognition rate of pale, soft, and exudative (PSE), reddish, firm, and non-exudative (RFN), and dark, firm, and dry (DFD) in training sets were 88.46%, 94.11%, and 92.31% respectively. For testing sets, predictive accuracy rates of three kinds were 84.62%, 94.11%, and 84.62% respectively. The study revealed the advantages of the established classifier, such as based on simple model and achieving high prediction accuracy, and so on. This study shows a simple, rapid, and non-destructive method by optical instrument to detect and classify pork based on its comprehensive quality. The study can be a milestone to develop a fast, accurate, and reliable technique for non-destructive detection of pork in slaughtering house, super markets and other required areas where quality is a concern. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Meats
Controlled terms:Agricultural machinery - Algorithms - Forecasting - Least squares approximations - Mean square error - Metadata - Nondestructive examination - Optimization - Particle swarm optimization (PSO) - Principal component analysis - Spectroscopy - Support vector machines
Uncontrolled terms:Comprehensive qualities - Nondestructive detection - Partial least square (PLS) - Particle swarm optimization algorithm - Projection algorithms - Projection coefficients - Root mean square errors - Spectroscopic technologies
Classification code:421 Strength of Building Materials; Mechanical Properties - 723 Computer Software, Data Handling and Applications - 801 Chemistry - 821.1 Agricultural Machinery and Equipment - 822.3 Food Products - 921.5 Optimization Techniques - 921.6 Numerical Methods - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.23.039
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 8>
Accession number:20150400457720
Title:Simulation of friction characteristics in sheet metal stamping forming
Authors:Zheng, Yanping (1); Wang, Lieliang (1); Shen, Silin (2)
Author affiliation:(1) College of Automobile and Traffic Engineering, Nanjing Forestry University, Nanjing, China; (2) Department of Mathematics, Xi'an Jiaotong-Liverpool University, Suzhou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:79-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the sheet metal forming process, the friction force between the sheet and the die is extremely complex, and its rule is not understood well enough. Based on friction theory, the friction force is divided into 4 components: the shear stress on the adhesion area, the shear stress on the boundary lubrication area, the ploughing force caused by protuberance on the die, and the shear stress on the area with much lubrication. Automobile panel products with high quality shall have no quality defects of stamping forming, such as fracture, wrinkle, spring back and surface defect, and the material flow of product shall be uniform and the thickness changes also shall be uniform during the forming process. Therefore, this article proposes that stamping forming quality index which includes defect quality index and thickness variation uniformity quality index. As different types of automobile panel contain different materials and have different quality problems, the defect quality index of different panels will also be different. The automobile's back plate reinforcement in this paper is complex internal covering parts, its main forming defect is fracture and wrinkle. So a novel criterion evaluating quality of sheet metal forming is developed. When the minimum thinning rate satisfies design requirements, the variance of each element thinning rate calculated in finite element simulation can be taken as evaluation index, and this index is inversely proportional to forming quality, in other words, the smaller evaluation index is, the more even sheet metal becomes, then the better forming we can obtain. In addition, the concept of equivalent friction coefficient is proposed, and the relationship between 4 components and friction force in FE simulation is built up; and then the accuracy of friction force in simulation is improved. Finally, numerical simulation and analysis about influence of friction and lubrication condition change on friction characteristics and forming quality is conducted. The result shows that the variance of each element thinning rate is direct proportional to friction coefficient, and the uniformity of sheet thickness becomes bad obviously when friction coefficient is great than 0.175. The total friction force is increasing persistently with the stamping development, and has the same variety trend and distinct terminal values in different lubrication conditions. It is proved that sheet forming quality can be enhanced by improving lubrication condition, and the components of friction force and their proportions can be known in the certain lubrication condition. After analyzing the curve of friction force with respect to time, the conclusions can be drawn as follows: 1)The change law of friction force at different nodes is different, and the thinning rate is directly proportional to the mean of friction force in thinning sheet area; 2) In thickening area, the relationship between friction force and thickening rate is confused, and the variety of friction force is more irregular with comparison to that in thinning area. The research provides a reference for reducing friction force, avoiding scratching of the surface of parts, extending the service life of die and controlling the sheet material flow, and has theoretical and practical sense for the improvement of sheet metal stamping quality. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Friction
Controlled terms:Automobile materials - Automobile parts and equipment - Automobiles - Finite element method - Fracture - Lubrication - Metal analysis - Metal forming - Metal stamping - Metals - Numerical analysis - Quality assurance - Quality control - Shear stress - Sheet metal - Stamping - Surface defects - Tribology
Uncontrolled terms:Boundary lubrications - Equivalent friction coefficients - Finite element simulations - Friction characteristics - Friction mechanism - Quality indices - Simulation and analysis - Stamping forming
Classification code:421 Strength of Building Materials; Mechanical Properties - 531 Metallurgy and Metallography - 535.1 Metal Rolling - 535.2 Metal Forming - 607.2 Lubrication - 662 Automobiles and Smaller Vehicles - 913.3 Quality Assurance and Control - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.23.011
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 9>
Accession number:20150400457713
Title:Design and optimization for length of longitudinal-flow threshing cylinder of combine harvester
Authors:Tang, Zhong (1); Li, Yaoming (1); Xu, Lizhang (1)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:28-34
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to optimize the length of longitudinal-flow threshing cylinder of combine harvester, in this paper the length-adjustable longitudinal-flow threshing cylinder was designed and used to conduct rice threshing and separating performance experiments. The grain distribution rules and distribution equation under the grid concave were developed. The length of longitudinal-flow threshing cylinder was optimized by calculating the optimal deflector helical angle of cylinder cover. The optimal length of the longitudinal-flow threshing cylinder was used to conduct rice threshing and separation performance confirmatory test. The result showed that when the feeding rate was 7 kg/s, adapted deflector helical angle of 7.64°, the optimal length of the longitudinal-flow threshing cylinder was 3 159.77 mm, and then the un-separated grain loss ratio could be controlled at the range from 0.2 % to 0.3%. The verification test result was about 0.29%. This study may provide a basis and method for design the length of longitudinal- flow threshing cylinder of combine harvester. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Agriculture
Controlled terms:Agricultural machinery - Cylinders (shapes) - Design - Grain (agricultural product) - Harvesters - Machine design - Optimization
Uncontrolled terms:Combine harvesters - Design and optimization - Distribution equations - Distribution rule - Grain distribution - Performance experiment - Separation performance - Threshing and separating
Classification code:408 Structural Design - 408.2 Structural Members and Shapes - 601 Mechanical Design - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.23.004
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 10>
Accession number:20150400457747
Title:Method and its application of natural quality evaluation of arable land based on self-organizing feature map neural network
Authors:Qie, Ruiqing (1); Guan, Xia (1); Yan, Xujiu (2); Dou, Shixiang (1); Zhao, Ling (1)
Author affiliation:(1) College of Economics and Management, Jilin Agricultural University, Changchun, China; (2) Institute of Land and Resources Surveying and Planning in Jilin Province, Changchun, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:298-305
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The characteristics and interactions of arable land quality components determine the external manifestation of arable land quality. It was the vital significance to objectively determine natural quality of arable land for arable land classification and grading. In this paper, advantage and disadvantage of the existing methods used in the arable land natural quality evaluation was analyzed, SOFM (self organizing feature map) neural network method was proposed to evaluate arable land natural quality basing on spatial database in Jiutai city of Jilin province. The nine evaluation indicators including surface soil texture, profile configuration, content of soil organic matter, soil pH value, barrier layer depth, soil salinity, effective soil depth, drainage condition and slope, were chosen and the corresponding database layer was established in the method. At the same time, attribute values were input and data were normalized. By training step for 1000, the system automatically generated 13 categories. Based on temperature potential productivity index and crop yield ratio of Jiutai city, evaluation index of arable land natural quality were calculated based on GIS. According the size of arable land natural quality indicators, the arable land natural quality of Jiutai city was divided into 3 grades. The ratios of I, II and III grade of arable land nature quality which was classified with proposed method in this paper to the total arable land area in Jiutai city were 42.13%, 30.40%, 27.47%, respectively. The natural quality evaluation results of arable land based on SOFM neural network were compared with that with farmland natural quality grading of update results in Jiutai city. The comparison results indicated that in the nature quality grade I with proposed method in this paper, the ratio of fifth, sixth and seventh grade which was classified with farmland natural quality grading of update results was 33.91%, 4.25%, 3.98%, respectively; in the nature quality grade II with proposed method in this paper, the ratio of fifth, sixth and seventh grade which was classified with farmland natural quality grading of update results was 4.58%, 25.38%, 0.45%, respectively; in the nature quality grade III with proposed method in this paper, the ratio of fifth, sixth and seventh grade which was classified with farmland natural quality grading of update results was 0.85%, 6.48%, 20.13%, respectively Quality grade I, II and III, classified with SOFM neural network corresponded to fifth, sixth and seventh grade of national nature grades classified with farmland natural quality grading of update results, figure spot coincidence rate and area overlap rate were 80.78% and 79.42%, respectively. The seasons for the discrepancies in the results of the two kinds evaluation method were that the slope factor was considered in proposed method, at the same time, uniform weights in Jiutai city, Jilin province was used in arable land natural quality grading of update results and qualitative description of the two kinds of evaluation methods for some indicators were quantified through information weighting value method, due to different quantization methods, different assignments. In this method, by self-organizing neural network combining with geographic information systems based on MATLAB, effectively influencing factors of arable land quality that related to soil and soil environment were integrated and quantification and space for spatial and non-spatial datum was realized. Especially, weights were subjectively determined, which made evaluation results more objective and true in propose method. And this method had more advantages in evaluating for highly nonlinear relationship between the arable land quality and its affecting parameters. Overall, the study method provides a new idea for arable land quality evaluation and broadens depth and breadth of arable land quality evaluation, and enhances the results credibility of natural quality evaluation of arable land. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Quality control
Controlled terms:Agriculture - Classification (of information) - Classifiers - Conformal mapping - Farms - Geographic information systems - Grading - Information systems - Land use - Neural networks - Self organizing maps - Soils
Uncontrolled terms:Arable land - Automatically generated - Jiutai city - Non-linear relationships - Potential productivity - Self organizing feature map neural network - Self-organizing feature map - Self-organizing neural network
Classification code:403 Urban and Regional Planning and Development - 483.1 Soils and Soil Mechanics - 716.1 Information Theory and Signal Processing - 723.3 Database Systems - 723.4 Artificial Intelligence - 802.1 Chemical Plants and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 903.2 Information Dissemination - 913.3 Quality Assurance and Control - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.23.038
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 11>
Accession number:20150400457721
Title:Numerical analysis for effects of different blade tip clearance on performance in mixed-flow pump
Authors:Li, Yibin (1); Hu, Penglin (1); Li, Rennian (1); Li, Penghui (3); Bi, Zhen (1)
Author affiliation:(1) School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou, China; (2) Key Laboratory of Fluid machinery and Systems, Lanzhou; Gansu Province, China; (3) Hunan XEMG Changsha Pump Works Co., Ltd., Changsha, China
Corresponding author:Li, Rennian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:86-93
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The mixed-flow pump has some good characteristics, such as high efficiency, good start performance, and wide working condition. The traditional design methods of mixed-flow pumps cannot evaluate the sensitivity of the tip clearance's impact on pump performance quantificationally. In order to reveal the tip clearance effect on the internal flow field and the performance of mixed-flow pump, and given the selection range of blade tip clearance, four mixed-flow pumps with different tip clearance values, 0, 0.5, 1.0, and 1.5 mm, respectively, were studied. The distorted triangle method was adopted to design the impeller and guide vane, and based on the software ICEM CFD to generate block hexahedron structured grids of the computational domain, and then the topological structure of the grids of the blade tip region was optimized. The internal flow field of the pumps was simulated based on the SST k-ω turbulence model and SIMPLEC algorithm, using the structured grid technology mentioned above, and the numerical simulation results were compared with the test experimental data, which agreed well with each other. The results show that the value of tip clearance have a significant effect on mixed-flow pump hydraulic performance, when tip clearance was 0.5 mm. The head-flow positive slope characteristic of the pump can be suppressed effectively, and the efficiency value of mixed-flow pump is highest at this time; when tip clearance was 0, the pump head-flow positive slope characteristic is relatively obvious; when tip clearance was 1mm, simulation values and experimental values matched well, so the SST k-ω model can simulate the flow characteristics of tip clearance of mixed-flow pumps well, so that the results of the performance prediction have some credibility. Under small flow conditions, small tip clearance values can restrain unstable positive slope features of mixed-flow pump. When tip clearance was 0.5mm, the performance of the pump with small tip clearance is the best. With the increasing of tip clearance value, tip leakage flow became outstanding gradually, the axis plane flow velocity of the near wall region of the impeller outlet and the vorticity change significantly, which indicates that tip clearance affects the axis plane velocity distributions of the impeller and the load distributions of the blades directly. As influenced by the frictional resistance and the viscous resistance of the wall, the impeller axis plane flow velocity of the impeller hub region and tip clearances areas is relatively small. When tip clearance increase, blades load of the impeller hub region and tip clearances areas decay rapidly, and it affects the performance ability of impeller blades. At the same time, serious mix permeability and entrainment effects come into being between the leakage flow near the blade tip and the main stream flow, and cause the significant decline in the axis plane flow velocity in the region near the blade tip of impeller outlet. At the moment, the jet effect of the tip leakage flow decays gradually, and the sphere of influence gradually extends to the entire blade tip region. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Computational fluid dynamics
Controlled terms:Flow fields - Flow measurement - Flow velocity - Friction - Impellers - Leakage (fluid) - Numerical analysis - Pumps - Stream flow - Turbulence models - Velocity - Velocity distribution
Uncontrolled terms:Computational domains - External characteristic - Frictional resistance - Leakage flow - Mixed flow pump - Performance prediction - Tip clearance - Topological structure
Classification code:452.3 Industrial Wastes - 601.2 Machine Components - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 921.6 Numerical Methods - 931.1 Mechanics - 931.3 Atomic and Molecular Physics
DOI:10.3969/j.issn.1002-6819.2014.23.012
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 12>
Accession number:20150400457731
Title:Identification of drought and frequency analysis of drought characteristics based on palmer drought severity index model
Authors:Zhou, Yuliang (1); Liu, Li (1); Zhou, Ping (1); Jin, Juliang (1); Li, Jianqiang (4); Wu, Chengguo (1)
Author affiliation:(1) School of Civil Engineering, Hefei University of Technology, Hefei, China; (2) State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Nanjing Hydraulic Research Institute, Nanjing, China; (3) College of Hydrology and Water Resources, Hohai University, Nanjing, China; (4) Water Resources and Hydropower Planning and Design General Institute, Ministry of Water Resources, Beijing, China
Corresponding author:Jin, Juliang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:174-184
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drought risk management is an effective countermeasure to drought disaster mitigation. Process identification and frequency analysis of drought characteristics are the basis for risk management. Currently, the major issues associated with drought process identification are: 1) consistency of hydrological drought indicators (e. g., surface runoff, soil moisture content, groundwater depth) is susceptible to the impact of human activities; 2) definitions of threshold values in drought process identification are usually lack of clear physical meaning, and the beginning and end time of drought process vary with these values; 3) traditional drought duration defined as the number of periods from the beginning to end time of drought process, may lead to identify the drought event with low intensity and several drought alleviation periods as the severe one due to its long duration; 4) drought intensity lacks time comparability. Therefore, in this study, we used the Palmer drought severity index (PDSI) method by taking the meteorological factors of less influenced as the input to determine the dry/wet states and the PDSI value at each period. Determination of the dry/wet states and the PDSI value at each period included five main steps: hydrological accounting based on meteorological and soil water characteristics data, calculation of climatic coefficients, analysis of the amount of climatically appropriate for existing conditions (CAFEC) precipitation, calculation of Palmer moisture anomaly z-index based on actual and CAFEC precipitation, and estimation of the dry/wet states and the PDSI value based on z-index. The dry/wet states consisted of dry period, wet period, transition period, transition period in dry spell, and transition period in wet spell. Then the drought process identification criteria were analyzed based on the dry/wet states and the PDSI value by trial and error method according to actual drought in the study area. Drought duration was defined as the number of periods under dry states, while the drought severity was estimated as summation of absolute value of negative moisture anomaly index, which was of time-comparability during a drought event. On the basis of the distribution of drought duration and drought severity generated by the frequency curve fitting method, their joint distribution was constructed via the GH Copula, and accordingly the estimation of drought recurrence periods at Kunming station from 1951 to 2011 were conducted. There were 43 droughts were identified, and the drought that occurred in 2009-2010 was the most severe drought event in the study period with the recurrence period of 64.7 years. Results showed that drought process indentified based on the PSDI model was consistent with the actual regional drought circumstances and the results by using runoff index methods, notwithstanding the disparity from that by applying the precipitation index that were not concerned with surface hydrological process. The proposed drought frequency analysis was of clear physical concept, and the expression of drought duration and severity was of physically reasonability. The results of this study can provide a reference for assessment of drought disaster hazard. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Drought
Controlled terms:Curve fitting - Disasters - Frequency estimation - Groundwater - Groundwater resources - Identification (control systems) - Moisture - Moisture determination - Risk assessment - Risk management - Runoff - Soil moisture
Uncontrolled terms:Copula functions - Drought characteristics - Drought frequency analysis - Frequency Analysis - Kunming - Palmer drought severity indices - Soil water characteristics - Trial-and-error method
Classification code:444 Water Resources - 483.1 Soils and Soil Mechanics - 484 Seismology - 731.1 Control Systems - 751 Acoustics, Noise. Sound - 801.4 Physical Chemistry - 921.6 Numerical Methods - 922.1 Probability Theory - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.23.022
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 13>
Accession number:20150400457746
Title:Land use ecological risk evaluation in Three Gorges Reservoir area based on normal cloud model
Authors:Zhou, Qigang (1); Zhang, Xiaoyuan (1); Wang, Zhaolin (1)
Author affiliation:(1) School of Tourism and Land Resources, Chongqing Technology and Business University, Chongqing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:289-297
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Some basic data couldn't be accurately acquired or quantitative evaluated in evaluation of land use ecological risk, so there are the fuzziness and uncertainty problems in the evaluation index and results. In order to solve this problem effectively, normal cloud model comprehensive evaluation model was introduced. In Normal cloud evaluation model, the status of each evaluation index can be intuitive found out and the influences of each evaluation index on land use ecological risk in Three Gorges Reservoir area can be objective reflect. With the LandSAT TM remote sensing data, social and economic data, environmental monitoring data of Three Gorges Reservoir area in the year of 2000 and 2012, the evaluating indexes system was built to evaluate the land use ecological risk in Three Gorges Reservoir area based on the PSR (pressure-state-response, PSR) model. In model, the ecological risk pressure indexes included the proportion of agricultural land, construction land scale, the industrial pollutants emission intensity, the strength of farmland non-point source pollution, road network density and population density; the state of ecological indexes included patch density, shape index, circumference surface integral dimension, concentration, average nearest neighbor distance; the risk response indexes included composite structure index, vegetation coverage, diversity index, the coordination degree of water and soil, land degradation rate. The evaluation standards were set up by referring to a large number of data and consulting relevant experts. Study results indicated that: 1) The level of average land use ecological risk belonged to the lower risk totally in Three Gorges Reservoir area. At the same time, the level of land use ecological risk had an increasing trend. The average normal cloud membership degrees of lower risk were the max in all risk levels both in 2000 and 2012. But the value decreased from 0.4233 to 0.4013 from 2000 to 2012 in Three Gorges Reservoir area. And the second risk level was medium risk. The value was 0.3955, near the value of lower risk tightly in 2012 year. 2) The land use ecological risk level had an increasing trend from northeast to southwest in Three Gorges Reservoir area. There were one county in low risk level, ten in lower risk level, six in medium risk level, and one in highest risk level in 2000. The number of counties in higher risk level and highest risk level increased obviously from 2000 to 2012. Three counties were added into higher risk level, and one added into highest risk level. Those counties distribute in southwest of Three Gorges Reservoir area. Changshou district, which land use ecological risk level increasing from lowest to highest rapidly, needed to be paid most attention especially. 3) The distribution and change of land use ecological risk level were different obviously in each part of Three Gorges Reservoir area. The head area of Three Gorges Reservoir area, including four counties in the Hubei province, belong lowest risk or lower risk area. And the change of risk level was weak. In the hinterland area of Three Gorges Reservoir area, the levels of land use ecological risk were not highest. But the change of risk level was obvious. In four counties, including Puling, Fengdu, Shizhu and Wanzhou, the risk levels increased. Only in Yunyang, the risk level of decreased. In the end area of Three Gorges Reservoir area, the level of use ecological risk was highest for most pollution. Appling normal cloud model, the uncertainty mapping of each evaluation index was realized, and the results had more objectivity through considering to randomness and fuzziness in the processes of evaluation index quantization and level division. The results offer references for land reasonable using and ecological protection policy making in Three Gorges Reservoir Area. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Land use
Controlled terms:Cloud computing - Degradation - Ecology - Fuzzy set theory - Fuzzy systems - Industrial emissions - Monitoring - Motor transportation - Pollution - Pollution control - Population statistics - Remote sensing - Reservoirs (water) - Risks - Soil pollution - Water pollution - Water treatment
Uncontrolled terms:Comprehensive evaluation model - Environmental Monitoring - Evaluation - Nearest neighbor distance - Non-point source pollution - Normal cloud model - Pressure state response (PSR) - Three gorges reservoir area
Classification code:403 Urban and Regional Planning and Development - 432 Highway Transportation - 441.2 Reservoirs - 445.1 Water Treatment Techniques - 451.1 Air Pollution Sources - 453 Water Pollution - 454.2 Environmental Impact and Protection - 454.3 Ecology and Ecosystems - 722.4 Digital Computers and Systems - 731.1 Control Systems - 802.2 Chemical Reactions - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 922.1 Probability Theory - 922.2 Mathematical Statistics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.23.037
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 14>
Accession number:20150400457715
Title:Design of corn high-stubble cutter and experiments of stubble retaining effects
Authors:Wang, Gang (1); Jia, Honglei (1); Zhao, Jiale (1); Li, Changying (1); Wang, Yu (1); Guo, Hui (1)
Author affiliation:(1) School of Biological and Agricultural Engineering, Jilin University, Changchun, China; (2) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun, China
Corresponding author:Jia, Honglei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:43-49
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to improve the productivity of land and protect the cultivated land environment in a ridge area of Northeast China, one mode of conservation tillage with high stubble for corn is currently emerging. This new conservation tillage aims to retain a certain height of stalk standing in the field, while using the other part of the stalk in other ways. The standing part of the stalk is sufficient to recover the field's fertility and also helps to avoid environmental pollution. Meanwhile, the other part of the stalk can feed livestock during the winter or be used as fuel in rural areas. One can see that this method has many advantages. Unfortunately, the existing corn harvesters can't realize this mode of conservation tillage. In order to mass-produce this mode of high-stubble conservation tillage, harvesters which can automatically retain high stubble are developed. Horizontal corn harvesters have some advantages, such as low grain breakage rate and impurity, and this practice is used widely all over the world. Adding the cutter to an existing two-row corn harvester is the main designing idea of this paper. Additionally, since different corn varieties and complex working conditions have different requirements, cutting height and cutting angle should be adjustable. Finally, the results of two experiments are presented. The first experiment was to vary the cutter head's height and the cutter angle, while measuring the cutting ratio (defined as the ratio between cut stalks to total stalks, expressed as a percentage). The second experiment tested the relationship between the stubble height (output parameter) and the cutter head's height above the ground (input variable) as well as the cutter angle (input variable). Some relations among cutter head's height, cutter angle, cutting ratio and resulting stubble height were presented; and these relations can be used to adjust cutter head's height to create a desired stubble height. We came to the conclusion that with the increasing of cutter head's height, cutting rate increases, and the cutting ratio's mean value increases from 90.16% to 95.43%. In the range of 0 to 15° of cutting angle, with the increasing of the angle between the cutter head and the ground, the cutting ratio's mean value increases from 90.17% to 95.42%. While varying the cutter head's height, the mean value of stubble height increases from 307 to 363 mm, it is to say that the average stubble height increases along with the elevation of cutter head's height. Similarly, while varying the angle between the cutter head and the ground, the mean value of stubble height increases from 329 to 341 mm. Broadly speaking, the average stubble height increases along with the increase of the angle between the cutter head and the ground. In conclusion, the cutter designed in this paper can help to realize the high-stubble conservation tillage in conjunction with existing horizontal corn harvesters, which has profound influence on promoting the high-stubble conservation tillage in ridge areas of Northeast China. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Cutting equipment
Controlled terms:Agricultural machinery - Agriculture - Cultivation - Harvesters - Rural areas - Soil conservation - Straw
Uncontrolled terms:Conservation tillage - Corn harvesters - Cultivated lands - Environmental pollutions - High stubbles - Input variables - Northeast China - Output parameters
Classification code:604.1 Metal Cutting - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2014.23.006
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 15>
Accession number:20150400457732
Title:Evaluation method for effects of drought disaster on yields of maize in Southwest China
Authors:He, Yongkun (1); Tang, Yuxue (1); Zhang, Jianping (1)
Author affiliation:(1) Meteorological Research Institute of Chongqing, Chongqing Engineering Research Center of Agrometeorology and Satellite Remote Sensing, Chongqing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:185-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Impacts of climate change on agriculture has received wide concerns, yet evaluation technology of the effect of the drought disaster on the crop yields needs further research particularly in developing countries. Maize cultivation occupies extremely important position in agricultural production in this region. It holds great importance to study the evolution of the drought to provide references for disaster prevention and avoiding disadvantages. Drought is the main meteorological disasters during maize growth periods, and high frequency and large-scale drought poses serious threat to maize growth and yield. Recently, the government departments and related research institutions have focused on the drought matter in Southwest. Based on the principle of similar climate growth period and agricultural production level, corn planting areas in Southwest China are divided into 6 sub-regions. Using the daily meteorological data and maize data from 63 representative stations in Southwest China from 1961 to 2010, the study calculated water profit and loss index in each sub-region, then computed the weighted sum of the water profit and loss index over the past three ten-day, finally got the ten-day wetness index. According to the ten-day wetness index and influence coefficient, the maize cumulative index was built. The study developed yield drought loss assessment model and verified the model by selecting some typical drought years and representative stations in each sub-region. The results showed that the wetness index by 10 days in the growth period had a good relationship with soil moisture. The assessment model of maize drought loss yield in 6 sub-regions passed F-test (p<0.05) and corn cumulative indices of drought in drought year in Southwest China had good relation to the yield loss in drought through the statistical analysis of the representative station. With changes of the same drought cumulative indices, there were slight differences in yield loss in each sub-region. Yield loss in the sub-regions of II and III were relatively small, while relatively large in the sub-regions of I and V. The model can estimate the yield loss in drought accurately, and provide references for application and deep research. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Drought
Controlled terms:Agriculture - Climate change - Crops - Cultivation - Developing countries - Disaster prevention - Disasters - Losses - Meteorology - Profitability - Societies and institutions - Soil moisture
Uncontrolled terms:Agricultural productions - Evaluation modeling - Government departments - Influence coefficient - Maize - Meteorological disasters - Research institutions - Yield
Classification code:443 Meteorology - 444 Water Resources - 451 Air Pollution - 483.1 Soils and Soil Mechanics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.1.1 Societies and Institutions - 901.4 Impact of Technology on Society - 911.2 Industrial Economics - 914.1 Accidents and Accident Prevention
DOI:10.3969/j.issn.1002-6819.2014.23.023
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 16>
Accession number:20150400457712
Title:Analysis on seeding process of pneumatic cylinder-type centralized rapeseed precision metering device
Authors:Li, Ming (1); Liao, Qingxi (1); Liao, Yitao (1); Shu, Caixia (1); Li, Lei (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan, China
Corresponding author:Liao, Qingxi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:17-27
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to obtain the relationship model between required negative and positive pressures values and the structural and operating parameters in the main metering processes at the absorbing, retaining and dropping stages, the seeding process of pneumatic cylinder-type centralized rapeseed precision metering device were analyzed. Through analyzing the influence of operational and structural parameters on the performance of pneumatic cylinder-type centralized rapeseed precision metering device, the working principle of the pneumatic cylinder-type centralized precision metering device was summarized, and its basic configuration was designed. Dynamic and kinematics models were established in the main metering processes at the absorbing, retaining and dropping stages, and Extended Discrete Element Method software was used for the simulation and calculation of absorbing process, based on which the relationship model between required negative and positive pressures values and the structural and operating parameters were established in seeding process. The results of extended discrete element method simulation analysis indicated that in order to ensure the reliable work of the metering device, the height of seeds should be limited within the 0.65D<inf>g</inf>, which was verified by the results obtained from our preliminary tests. Then the JPS-12 test-rig for the performance of the rapeseed metering device was adopted to conduct the single factor experiments, which showed that the quality index reached above 89.1% and the coefficient variation was 3.76% when the rotational speed was 20 r/min and the positive pressure value was 2 200 Pa and the vacuum was -2 200 Pa. The experimental results were in accordance with the analytical result of dynamic model. The analysis provided theoretical foundation for optimizing the operational and structural parameters of the centralized metering device. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Structural analysis
Controlled terms:Agricultural machinery - Computer software - Cylinder configurations - Cylinders (shapes) - Dynamic analysis - Kinematics - Models - Oilseeds - Pneumatic drives - Pneumatic equipment - Pneumatics - Seed
Uncontrolled terms:Discrete element method simulations - Kinematics simulation - Metering devices - Pneumatic Cylinders - Rapeseed - Simulation and calculations - Single-factor experiments - Theoretical foundations
Classification code:408.1 Structural Design, General - 408.2 Structural Members and Shapes - 422.2 Strength of Building Materials : Test Methods - 612.1 Internal Combustion Engines, General - 632.3 Pneumatics - 632.4 Pneumatic Equipment and Machinery - 723 Computer Software, Data Handling and Applications - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 902.1 Engineering Graphics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.23.003
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 17>
Accession number:20150400457725
Title:Reducing nitrogen leaching losses from paddy field under water-saving irrigation by water table control
Authors:He, Yupu (1); Zhang, Zhanyu (1); Xu, Junzeng (1); Yang, Shihong (1); Hong, Dalin (2)
Author affiliation:(1) College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing, China; (2) Nanjing Hydraulic Research Institute, Nanjing, China
Corresponding author:Yang, Shihong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:121-127
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Effects of controlled drainage (CD) on nitrogen leaching losses from paddy field under controlled irrigation (CI) were investigated. Water table control levels were managing with the use of a lysimeter equipped with an automatic water table control system. Three drainage treatments were implemented, namely, controlled water table 1, controlled water table 2, and controlled water table 3. For controlled water table 1, the water table control levels were adjusted daily based on the actual water table depths that were measured by using a water table observation well. Water table control levels in controlled water table 2 were controlled based on the rice root zone depths in different stages according to the water table management that was tested in the humid regions of Eastern Canada and Midwestern United States. For controlled water table 3, the water table control levels in different stages were selected based on previous studies in paddy field of Southeast China. The water table control levels in the later tillering stage and milk stage were also adjusted depending on the characteristics of rice growth and cultivation needs. Experiments were conducted in nine drainage type lysimeters with a mobile shelter and gallery. Each lysimeter had an area of 2.5 m × 2 m and a depth of 1.3 m. Influence of rainfall was avoided using the mobile shelter to strictly regulate the soil moisture in CI. Each lysimeter was individually irrigated and drained using a pipe installed with a water meter and a tube (40 mm in inner diameter) installed at 1.2 m below the soil surface, respectively. Subsurface drainage was conducted based on the water table control levels by using an automatic water table control system, which was installed on each drain tube in the gallery. Subsurface drainage water were collected twice at 2d intervals after each fertilizer application followed by 4d intervals. A 7d sampling interval was used during the rest time. NH<inf>4</inf><sup> </sup>-N and NO<inf>3</inf><sup>-</sup>-N concentrations in the water samples were analyzed using an ultraviolet-visible spectrophotometer. NH<inf>4</inf><sup> </sup>-N or NO<inf>3</inf><sup>-</sup>-N leaching loss was calculated by multiplying the subsurface drainage water volume between the two dates by the NH<inf>4</inf><sup> </sup>-N or NO<inf>3</inf><sup>-</sup>-N concentration in the sample taken at the latter date. The results showed increasing water table control levels resulted in less subsurface drainage water from CI paddy field. The subsurface drainage water from controlled water table 1 was 179.4mm, which was 8.4% and 37.2% lower than those from controlled water table 2 (195.9 mm) and controlled water table 3 (285.8 mm), respectively. As the water table control levels increased, NH<inf>4</inf><sup> </sup>-N concentration in subsurface drainage water increased, however, NO<inf>3</inf><sup>-</sup>-N concentration decreased. Average NH<inf>4</inf><sup> </sup>-N concentration in the subsurface drainage water from controlled water table 1 was 9.3% and 27.3% higher than those from controlled water table 2 and controlled water table 3, respectively. Average NO<inf>3</inf><sup>-</sup>-N concentration in the subsurface drainage water from controlled water table 1 was 32.6% and 1.8% lower than those from controlled water table 2 and controlled water table 3, respectively. Significantly, less NO<inf>3</inf><sup>-</sup>-N leaching loss from CI paddy field was observed as the water table control levels increased. NO<inf>3</inf><sup>-</sup>-N leaching loss from controlled water table 1 was 0.27 kg/hm<sup>2</sup>, with a significant reduction of 0.16 and 0.61 kg/hm<sup>2</sup>, respectively, compared with controlled water table 2 and controlled water table 3. NO<inf>3</inf><sup>-</sup>-N leaching loss from controlled water table 2 was significantly reduced by 0.45 kg/hm<sup>2</sup> compared with controlled water table 3. The application of CD with suitable water table control level could effectively reduce NO<inf>3</inf><sup>-</sup>-N leaching loss from CI paddy field. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Groundwater
Controlled terms:Control systems - Drainage - Groundwater flow - Irrigation - Leaching - Lysimeters - Nitrogen - Soil moisture - Soil surveys - Tubes (components) - Wastewater disposal - Water conservation
Uncontrolled terms:Controlled drainage - Controlled irrigations - Fertilizer applications - Nitrogen leaching - Paddy fields - Subsurface drainages - Ultraviolet visible spectrophotometer - Water table management
Classification code:401 Bridges and Tunnels - 406 Highway Engineering - 442 Flood Control; Land Reclamation - 444 Water Resources - 444.2 Groundwater - 452.4 Industrial Wastes Treatment and Disposal - 483.1 Soils and Soil Mechanics - 502 Mines and Quarry Equipment and Operations - 533.1 Ore Treatment - 616.1 Heat Exchange Equipment and Components - 731.1 Control Systems - 804 Chemical Products Generally - 821.3 Agricultural Methods
DOI:10.3969/j.issn.1002-6819.2014.23.016
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 18>
Accession number:20150400457750
Title:Proper modified atmosphere packaging for delaying quality changes of pomfret (Pampus argenteus) during chilled storage and prolonging its shelf life
Authors:Lan, Weiqing (1); Xie, Jing (1); Gao, Zhili (1); Shi, Jianbing (1); Yang, Shengping (1); Zhu, Ruiqi (1); Zhu, Feng (1)
Author affiliation:(1) College of Food Science and Technology, Shanghai Ocean University, Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, Shanghai, China
Corresponding author:Xie, Jing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:324-331
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The aim of this work was to study the influence of modified atmosphere packaging (MAP) on the shelf-life of fresh pomfret (Pampus argenteus) during chilled storage and to find the proper atmosphere components of MAP for prolonging the shelf life of pomfret fillets. Fresh pomfret samples were obtained directly from the local fish market and transported to the laboratory with ice immediately. After being gutted, washed, filleted and trimmed in a water-ice mixture, samples were packaged under three different atmosphere components (MAP1, 20%/80% CO<inf>2</inf>/N<inf>2</inf>; MAP2, 50%/50% CO<inf>2</inf>/N<inf>2</inf>; MAP3, 80%/20% CO<inf>2</inf>/N<inf>2</inf>) and the control group was packaged with air (AIR), the initial gas/product ratio was 3: 1 in all packages. Packaged pomfret fillets were stored at (4±1) and monitored at intervals of 2 days. Samples were assessed by sensory, microbiological (total viable count, TVC) and physico-chemical (total volatile basis nitrogen (TVB-N), K-value, tri-methylamine nitrogen (TMA-N), pH value) evaluation. After 4 days of storage, the groups of MAP and AIR were different significantly (P<0.05) on the values of sensory evaluation, TVC, TVB-N and TMA-N. Fillets packaged with AIR were the first to present signs of degradation reaching rejection threshold values for all evaluated parameters. The shelf life of AIR was only 4-5 days according to sensory assessment, for which the corresponding microbiological assessment was also showed an increased curve. Meanwhile, the increase of pH, TVB-N, K-value and TMA-N values were significantly (P<0.05) delayed in MAP groups when compared to AIR group. In MAP fillets, TVC was lower than 10<sup>7</sup> CFU/g for a longer period. The results of quality index were showed that the protective effect of MAP, and the MAP3 group (CO<inf>2</inf>/N<inf>2</inf>, 80%/20%) could extend the shelf-life of pomfret fillet samples by 6-8 days as compared to the control group. However, the trend of pH value raised up after a decline was not found in MAP groups. The results indicated that examination of pH could not be a useful indicator of quality changes in pomfret fillets. The total number of colonies decreased slightly during the early period of storage, which showed that CO<inf>2</inf> can inhibit the increase of TVC. All microbial, chemical and physical traits revealed the effect of different MAP studied when concentration of CO<inf>2</inf> was less than 80%, especially those with a higher percentage of CO<inf>2</inf>, MAP application added. The shelf-life of pomfret samples can be extended from 4 days to 6-12 days and the fresh keeping effects of group with 80%CO<inf>2</inf> 20%N<inf>2</inf> treatment is better. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:44
Main heading:Modified atmosphere packaging
Controlled terms:Carbon dioxide - Energy storage - Ice control - Nitrogen - Packaging - pH - Quality control - Water quality
Uncontrolled terms:Atmosphere components - Pampus argenteus - Physico-chemicals - Protective effects - Rejection threshold - Sensory evaluation - Shelf life - Total viable counts
Classification code:443.3 Precipitation - 453.2 Water Pollution Control - 694.1 Packaging, General - 702 Electric Batteries and Fuel Cells - 801.1 Chemistry, General - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 913.3 Quality Assurance and Control
DOI:10.3969/j.issn.1002-6819.2014.23.041
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 19>
Accession number:20150400457711
Title:Design and experiment of noncircular gears transplanting mechanism based on pitch curve with nonfunction expression
Authors:Li, Ge (1); Ying, Kongyue (1); Zheng, Fengjun (2); Gu, Jinbo (2); Xu, Zhiwei (2)
Author affiliation:(1) School of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou, China; (2) Zhejiang Xiaojing Machinery Manufacturing Co., Ltd., Shaoxing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:10-16
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Design documents about non-circular gears were firstly given with pitch curve functions of gears, and then tooth profiles of non-circular gears were designed according to the design principle of the gear. Because of complicated pitch curve of non-circular gear, in the reverse design process of non-circular gear's transplanting mechanism, it was difficult to use the function to cover some of the details of non-circular gear pitch curve, which made the study of rotary transplanting mechanism with non-circular gears be carried on, only if a kind of curve function was given. It influenced further study of non-circular gear transplanting mechanism. Aiming at the problem that it was difficult to determine the non-circular gear pitch curve when reversing, this paper studied non-circular gear pitch curve in the expression of numerical points form, and put forward a method of non-circular gear pitch curve in the expression of non-function. The phenomenon of concave or nonsmooth connection in the first joint curve would often appear when the tooth top data of surveying and mapping was fit. So curve correction was needed. It was difficult to find a new suitable function to fit the corrected tooth top data because the original fitting function of addendum curve was not used for the corrected tooth top data. Therefore, this paper proposed a method that the corrected tooth top curve was expressed by the data of addendum circle's numerical point. The method overcame the limitation of designing non-circular gears transplanting mechanism when the function of pitch curve was given, and it also avoided the problem that it was difficult to find a new suitable function to fit the corrected tooth top data. Numerical point data of non-circular gear pitch curve was obtained by moving the addendum circle an addendum distance to rotation center. Then non-circular gear pitch curve with non-function expression was obtained, which made the design of the non-circular gear more flexible. Using numerical analysis method, the method of solving the seedling needle trajectory was studied, when non-circular gear pitch curve was in the expression of non-function. The kinematics analysis of transplanting mechanism was carried out. Using the design method of human-computer interaction, a software of optimization design of transplanting mechanism was written, to which that seedling needle trajectory met the planting requirements was the optimization target. The software of visualizing characteristics of mechanism motion was used to optimize the structure, and a group of structural parameters which met the agronomic requirements were obtained. The prototype of transplanting mechanism was manufactured based on the optimized structural parameters. The seedling needle tip point's relative trajectories obtained from high-speed camera and theory study were the same, which indicated that manufactured transplanting mechanism met the requirement of actual testing. According to the field planting experiment, manufactured transplanting mechanism has good seedling upright degree, high precision of fetching seedlings, less seedling injury and also satisfies the requirement of machine planting. The field planting experiment also proves the correctness of reversing of non-circular gears transplanting mechanism based on non-function expression of non-circular gears pitch curve. The research results provided the reference for the research and development of core working parts of high speed transplanter. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:14
Main heading:Gears
Controlled terms:Agricultural machinery - Curve fitting - Design - High speed cameras - Human computer interaction - Mechanisms - Needles - Numerical methods - Optimization - Seed - Trajectories
Uncontrolled terms:Kinematics analysis - Non-circular gears - Nonfunction expression - Planting experiments - Research and development - Rotary transplanting mechanisms - Structural parameter - Transplanting mechanisms
Classification code:404.1 Military Engineering - 408 Structural Design - 461.4 Ergonomics and Human Factors Engineering - 601.2 Machine Components - 601.3 Mechanisms - 742.2 Photographic Equipment - 819.6 Textile Mills, Machinery and Equipment - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 921.5 Optimization Techniques - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.23.002
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 20>
Accession number:20150400457735
Title:Diameter measurement method for immature apple based on watershed and convex hull theory
Authors:Li, Wenyong (1); Chen, Meixiang (1); Xu, Shupo (3); Chen, Xinyou (3); Qian, Jianping (1); Du, Shangfeng (2); Li, Sha (1); Li, Ming (1)
Author affiliation:(1) National Engineering Research Center for Information Technology in Agriculture, Beijing Academy of Agricultural and Forestry Sciences, Beijing, China; (2) College of Information and Electrical Engineering, China Agricultural University, Beijing, China; (3) Beijing Nankou Farm, Beijing, China
Corresponding author:Li, Ming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:207-214
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In agriculture field, the knowledge about the size of immature fruit in its growing period could be helpful to the aspects such as precision fertilization and irrigation, training and pruning, yield estimation and harvest stage determination. Thus, it can improve the fruit yield and quality. However, the most important premise is the fruit detection and the size calculation in natural condition. The color of fruits on tree is very similar with their surrounding objects, so that the recognition and size calculation is very difficult in natural condition. This paper proposed an algorithm of diameter measurement for immature apple based on the morphological reconstruction, the watershed and convex hull theory. Firstly, the images were acquired using the JV205 cameras which were installed in front of the apple trees with the distance of about 1-2 m, whose resolution was 4 608 pixels × 3456 pixels; and acquisition time was from June 1th, 2014 to September 30th, 2014. Before preprocessing, the images were cropped into 1400 pixels × 1100 pixels to get the scope of the target apples. In order to enhance the visibility of the target area, the morphological reconstruction operation was used before the edge detection. Secondly, the rough contour of target fruit was extracted by the dilation and erosion operation using micro-disk structure element with a radius of two pixels. After the above image preprocessing, excessive local minimum points, which were caused by occluded leaves and uneven illumination, were merged using the bresenham algorithm. And then the overlapping target fruits were segmented by distance transform and improved watershed algorithm. Later, the contours of segmented target region were tracked and the continuous smooth contour curve was extracted using convex hull on the edge of the segmentation images. Finally, the entire circle was reconstructed using the three different points on the reserved true target contour based on the circle feature principle. Thus, the center and radius parameters were estimated and the precise detection of target fruit was realized. In order to verify the algorithm accuracy, a total of 4 typical target apples and 96 images were selected in the experiments. The reference object, table tennis ball was 200 pixels and its actual size was 40 mm. So the calibration coefficient was 0.2 mm/pixel. The result of preprocessing showed that the image morphological reconstruction could not only weaken the brightness of the background, but also maintain the edge of target fruit. After the edge detection and structure expansion with a radius of two pixels, the contour of the fruit had been acquired, but there were some defects due to the fact that some fruits were shaded by leaves. At last, the calculated results were compared with the manual measurement ones. The experiment results showed that the minimum root mean square error (RMSE) and the mean value were 1.91 mm and 2.27 mm, respectively. In addition, it was found that the calculation result of the flat apples had larger error and the reason was that the radius of fitting circle was less than the actual one. The size class of fruit in market is mostly expressed in millimetre and the change from class size to another is often 5 mm or 0.5 cm. So without considering the flat apples, this method can meet the market fruit's grading requirement. In conclusion, the paper proposed a new approach to deal with segmentation for overlapping and occluded apples and to realize size detection and precise measurement of immature fruits in natural condition. And the results were consistent with the manual measurement, which could meet the producers' demand to precision management during the fruit growth period and had a good practicality. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Fruits
Controlled terms:Algorithms - Commerce - Computational geometry - Edge detection - Forestry - Grading - Image processing - Image segmentation - Mean square error - Morphology - Pixels - Volume measurement - Watersheds
Uncontrolled terms:Algorithm accuracies - Calibration coefficients - Convex hull - Diameter Measurement - Dilation and erosions - Morphological reconstruction - Precision fertilizations - Root mean square errors
Classification code:444.1 Surface Water - 716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 821.0 Woodlands and Forestry - 821.4 Agricultural Products - 911.2 Industrial Economics - 913.3 Quality Assurance and Control - 921 Mathematics - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 943.2 Mechanical Variables Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.23.026
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 21>
Accession number:20150400457745
Title:Tensile properties of alkaline lignin-poly vinyl alcohol film with formaldehyde crosslinker
Authors:Su, Ling (1); Fang, Guizhen (1)
Author affiliation:(1) Key Laboratory of Bio-based Material Science and Technology of Ministry of Education, Northeast Forestry University, Harbin, China
Corresponding author:Fang, Guizhen
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:281-288
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Industrial alkaline lignin-poly (vinyl alcohol) cross-linked film was prepared by casting. The effects of the dosage of industrial alkaline lignin, formaldehyde and the solution temperature, pH value and cross-linking time on the tensile properties of composites were investigated in a single factor experiment. Results showed that due to the cross-linking reaction, the viscosity of the cross-linked solution was higher than the blend solution. The optimum condition to prepare films of best mechanical properties was that the mass ratio of alkaline lignin (AL) and polyvinyl alcohol (PVA) 2:8, formaldehyde 8.8% of the dry matter, cross-linking time 40 min, the solution temperature 90, and pH 9.Incorporation of 20% alkaline lignin material into PVA improved the tensile properties of films. Under the best conditions, the elongation-at-break (EB) of neat PVA film and the AL-PVA cross-linked film was 205% and 236% respectively and the tensile strength (TS) was 52 and 46 MPa, respectively. The ATR-FTIR analysis showed that the cross-linking reaction between AL and PVA (1799) was present. Compared with neat PVA film, the tanδ magnitude and the Tg magnitude of AL-PVA reaction film were both decreased a little, which indicated that the addition of AL caused the increase in the distance between PVA molecules and the molecular mobility of the composite materials. The results have provided valuble information for design of the films. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Crosslinking
Controlled terms:Alkalinity - Aluminum - Films - Formaldehyde - Lignin - Mechanical properties - Polyvinyl alcohols - Tensile properties - Tensile strength
Uncontrolled terms:Cross-linked films - Crosslinking reaction - Elongation at break - Molecular mobility - Poly (vinyl alcohol) (PVA) - Properties of composites - Single-factor experiments - Solution temperature
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 541.1 Aluminum - 801.1 Chemistry, General - 802.2 Chemical Reactions - 804.1 Organic Compounds - 815.1.1 Organic Polymers - 933 Solid State Physics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.23.036
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 22>
Accession number:20150400457739
Title:Determination method of electric shock current based on parameter-optimized least squares support vector machine
Authors:Han, Xiaohui (1); Du, Songhuai (1); Su, Juan (1); Guan, Haiou (2); Shao, Limin (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing, China; (2) College of Information Technology, Heilongjiang Bayi Agricultural University, Daqing, China
Corresponding author:Du, Songhuai
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:238-245
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Currently, residual current operated protective devices (RCDs) have a wide range of application in low voltage power grids and play an important role in preventing electric shock hazards and avoiding fire disasters caused by ground fault. But, the stocking current of the animals and human beings has no relationship with the setting value of action current from the protection devices, and the root mean square (RMS) value of residual current detected is considered the current value to determine if the protector acts or not. Theoretical analysis and operation experiences indicate that such criterion is unavailable in identifying the shocking current signals of the animals and human beings from the summation leakage current. Thus, in order to identify the electric shock signal from the summation leakage current automatically and accurately, intelligent information processing techniques are adopted and identification method based on least square-support vector machine (LS-SVM) with grid search and cross validation optimization are proposed. Firstly, through the experiments simulating various scenarios of rabbits electric shocking on the electric shock experiment platform of residual current operated protective devices(RCDs), signal data of 800 sample points before the one cycle and after three cycles of electric shock are used as electric shock sample data obtained by fault recorder to get the leakage current and electric shock current waveform on the electric shock process of the power supply voltage at maximum time, zero time, and any time. Secondly, the above sample data needed to be filtered to reduce the impact of the non-stationary for noise data. Then, the leakage currents of sampling points are combined into a high dimensional feature vector which is input into LS-SVM and the corresponding electric current of sampling point is employed as output of LS-SVM. The relation between input and output is trained by applying grid search and cross validation to determine the optimal parameters of LS-SVM automatically, and the ideal model of electric shock signal is obtained. Thirdly, a total of 75 groups of sample data are used as the research object. Among them 10 groups of sample data are used as testing samples, with the experimental results showing that when 20 groups of sample data are used as training samples, the identification mean square error is 14.0040. When 40 groups of sample data are used as training samples, the identification mean square error is 11.7469. When 65 groups of sample data are used as training samples, the identification mean square error is 11.1849. In comparison with the electric shock current identification method proposed method recently, the radial basis function (RBF) neural network method, the proposed method has the lower identification error. Consequently, it can identify the shocking current signals of the animals and human beings from the summation leakage current more accurately and provide a more reliable theoretical basis for developing new generations of adaptive residual current protection devices, which is based on the electric current component of the animals and human beings causing its action. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:15
Main heading:Electric variables measurement
Controlled terms:Animals - Disaster prevention - Electric currents - Electric grounding - Electric power systems - Identification (control systems) - Image retrieval - Leakage currents - Least squares approximations - Mean square error - Optimization - Radial basis function networks - Sampling - Signal detection - Smart power grids - Support vector machines - Vectors
Uncontrolled terms:Cross validation - Electric shock currents - Grid search - Intelligent information processing - Least square support vector machines - Least squares support vector machines - Radial basis function neural networks - Residual current protection device
Classification code:461 Bioengineering and Biology - 471 Marine Science and Oceanography - 701.1 Electricity: Basic Concepts and Phenomena - 706.1 Electric Power Systems - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 723.4 Artificial Intelligence - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 801 Chemistry - 814 Leather and Tanning - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822 Food Technology - 914.1 Accidents and Accident Prevention - 921 Mathematics - 942.2 Electric Variables Measurements
DOI:10.3969/j.issn.1002-6819.2014.23.030
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 23>
Accession number:20150400457719
Title:Weak fault diagnosis for rolling element bearing based on MED-EEMD
Authors:Wang, Zhijian (1); Han, Zhennan (1); Liu, Qiuzu (1); Ning, Shaohui (1)
Author affiliation:(1) College of Mechanical Engineering, Taiyuan University of Technology, Taiyuan, China
Corresponding author:Han, Zhennan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:70-78
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Abstract: Under the complex environment, rotating machinery such as wind turbine gearboxes has multi-gearing and multi-bearing. The dynamic responses of these components are complex and interfering with each other. It is usually difficult to diagnose their potential faults. Especially when multiple faults and strong background noise coexist, vibration signals excited by several faults are combined with each other nonlinearly and non-stationary, which makes the observed vibration signals rather complex and difficult to identify each fault by using traditional methods. Especially the rolling bearing's fault feature under strong background noise is very weak and usually overwhelmed by noise. In this paper, minimum entropy deconvolution (MED) and ensemble empirical mode decomposition(EEMD) were combined for rolling bearing's weak fault diagnosis. EEMD is a self-adaptive analysis method and can decompose a complicated signal into a series of intrinsic mode functions (IMFs) according to the signal's local characteristics. EEMD is more accurate and effective for diagnosing the faults of rotating machinery than MED, so it has been used in the fault feature extraction of rolling bearing. However, if the frequency components in the signal are too complex and the background noise is very strong, they will affect the decomposition result, therefore it is very important to improve the signal-to-noise ratio of the original signal. MED searches for an optimum set of filter coefficients that can recover the output signal with the maximum value of kurtosis, which is an indicator that reflects the peak of a signal, so MED technique aims to extract the fault impulses while minimizing the noise and therefore resulting in clear detection results even under high noise, which can remedy the shortage of EEMD. In this paper, MED and EEMD were combined for the simulation signal and the wind turbine gearbox. Firstly, MED was used as the pre-filter to refine the vibration signal, and the strong background noise of rolling bearing was decreased by the MED method. Secondly, the given signal above was processed by the EEMD, and the amplitude of the added white noise could be determined through a trial-and-error method, which could be implemented based on minimizing the problems of mode aliasing. At last the sensitive intrinsic mode functions (IMFs) were analyzed by cyclic autocorrelation function (CAF), which could be applied to separate out the modulators effectively, especially for the weak modulators due to fault effects that could not be detected by other conventional technologies. We analyzed the wind turbine gearbox by combining CAF with EEMD, when the amplitude of the added white noise was 0.4 and the number of the ensemble was 100, the components 28 and 302 Hz corresponded to twice rotational frequency of high speed shaft and fault frequency of outer ring of #10 bearing. The result showed that high-speed shaft of wind turbine gearbox was slightly bent and there was slight pit on the face of outer rings of #10 bearings. The analyzed results demonstrate that the proposed method is an effective approach in identifying weak fault feature under strong background noise of rotating machinery. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Fault detection
Controlled terms:Autocorrelation - Bearings (machine parts) - Bearings (structural) - Dynamic response - Entropy - Feature extraction - Functions - Machinery - Minimum entropy methods - Roller bearings - Room and pillar mining - Rotating machinery - Signal analysis - Signal detection - Signal processing - Signal to noise ratio - Turbine components - White noise - Wind turbines
Uncontrolled terms:Ensemble empirical mode decomposition - Gearbox - Minimum entropy deconvolution - Multi faults - Weak faults
Classification code:408.1 Structural Design, General - 408.2 Structural Members and Shapes - 422 Strength of Building Materials; Test Equipment and Methods - 502.1 Mine and Quarry Operations - 601 Mechanical Design - 615.8 Wind Power (Before 1993, use code 611 ) - 617 Turbines and Steam Turbines - 641.1 Thermodynamics - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.23.010
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 24>
Accession number:20150400457724
Title:Optimization of ponds allocation in small hilly watershed in Southwestern China
Authors:Liu, Weiping (1); Liu, Juan (1); Wei, Chaofu (1)
Author affiliation:(1) College of Resources and Environment, Southwest University, Chongqing, China
Corresponding author:Wei, Chaofu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:112-120
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The annual rainfall in southwestern China is usually abundant in hilly areas. Nevertheless, due to the effects of terrain and disproportional rainfall distribution, the efficiency of rainwater use for farmland irrigation is actually low. Coupled with the weak storage capacity and the lack of water reservation projects, the severe shortage of water appears in some districts. As for ponds widely applied in hilly area, the phenomenon frequently occurs that large idle capacity and severe overflow lead to low irrigation utility. Moreover, gravity irrigation is regarded as a general requirement for newly-built ponds so as to reduce cost of pumping irrigation. This paper discusses an optimized allocation method of ponds under the primary goals of relatively adequate rainwater harvest for pond-irrigating and maximum gravity irrigation rate in a hilly watershed. The method takes the natural advantage of terrain elevation difference of hilly areas into account. Based on the actual situation of study area, the pond-irrigation was set to aim at meeting the water requirement of fruiters, vegetables and dry crops from July to October. With the terrain data, the hilly watershed was divided into 38 catchment areas by hydrological analysis tool in ArsGIS software. The crop irrigation schedule from July to October was determined by referring to technical code for rainwater collection, storage and utilization. Then the actual irrigation requirement in each catchment area could be calculated with the crop cultivated area being computed respectively. Given the local annual average rainfall from July to October, the minimum threshold was calculated to guarantee the rainwater harvest for 200 m<sup>3</sup> pond, with which the catchment path of the small watershed was extracted based on the surface runoff-flowing model. Meanwhile, the appropriate number of 200 m<sup>3</sup> ponds to build in each catchment area was figured out to meet the crop irrigation requirement from July to October with reference to the irrigation schedule. Finally, the allocation of ponds would be optimized by setting rational allocation constraints as follows: firstly, slope of the site should be smaller than 5 degree; secondly, the pond should be built within 500 m from rural residential areas, 100 m from crop areas and 100 m away from land for mining and industry; thirdly, the sites would lie along the first level catchment path to avoid the overlap of the water water-collecting area between the adjacent ponds and the higher position would be given priority to with the two constraints above satisfied. Fourthly, if the number of sites matching the first three constraints was larger than the appropriate number to be built, the higher position site would be preferred. The suitable pond sites are screened in the catchment path with ArcGIS spatial analysis. 65 sustainable sites for 200 m<sup>3</sup> pond are selected using this method. The average water-collecting area of all the pond sites was estimated to be 0.31 ha and prospected to guarantee the relatively adequate rainwater harvest of 200 m<sup>3</sup> pond under the condition of rainfall in study area. Furthermore, the gravity irrigation rate of farmland within the watershed came to nearly 50%, showing that the method contributes to reduce the irrigation cost. Additionally, the method can provide guidance for the allocation of pond in different specifications and reference for other kind of rainwater harvesting engineering in land consolidation project planning in hilly areas. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Lakes
Controlled terms:Catchments - Cost reduction - Crops - Digital storage - Farms - Harvesting - Irrigation - Landforms - Optimization - Ponds - Precipitation (chemical) - Rain - Runoff - Watersheds
Uncontrolled terms:Hydrological analysis - Irrigation requirements - Irrigation schedule - Optimized allocation - Rain water harvesting - Rainfall distribution - Rainwater collections - Rural residential areas
Classification code:443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 454.3 Ecology and Ecosystems - 481.1 Geology - 722.1 Data Storage, Equipment and Techniques - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.23.015
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 25>
Accession number:20150400457718
Title:Effects of sub-soiling on soil physical quality and corn yield
Authors:Li, Xia (1); Tang, Mingjun (1); Zhang, Dongxing (2); Wang, Weixin (1); Cui, Tao (2)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Shihezi University, Shihezi, China; (2) College of Engineering, China Agricultural University, Beijing, China
Corresponding author:Zhang, Dongxing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:65-69
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:oil compaction and water scarcity are two major issues concerning agricultural production in North China Plain. In order to increase the utilization of natural rainfall in the dry farmland in the semi- arid area, break up plough pan, achieve the purpose of water conservation and increase the crop production. The effects of two treatments, i. e. sub-soiling and local rotary tillage on soil physical properties and yield of maize were compared in Jining from 2011 to 2013. The experiment was designed as a randomized complete block and ANOVA was used to assess the treatment effects. The results showed that: Except the surface soil layer (0-15 cm), the values of soil bulk density and penetration resistance are significantly (P<0.05) lower than those of rotary tillage during all growth period, especially during silking stage. What's more, the values of water content of sub-soiling at 25-35 cm soil layer were significantly (P<0.05) higher than those of rotary tillage by 9.45% (2012) and 8.64% (2013) during siliking stage. However, maize yield is significantly (P<0.05) increased by 6.08%-7.23% while the effect of thousand seed mass is closing between two treatments. In conclusion, this experiment has important value in extending sub-soiling management practices which may be a more sustainable approach to farming in North China Plain. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Soils
Controlled terms:Agricultural machinery - Agriculture - Arid regions - Conservation - Crops - Cultivation - Water conservation - Water content
Uncontrolled terms:Agricultural productions - Bulk density - Management practices - Penetration resistances - Soil physical property - Soil physical quality - Surface soil layers - Yield
Classification code:444 Water Resources - 454 Environmental Engineering - 483.1 Soils and Soil Mechanics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2014.23.009
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 26>
Accession number:20150400457726
Title:Soil water and salt movement and spatial distribution of fine alfalfa roots under drip irrigation
Authors:Lu, Weihua (1); Ren, Aitian (1); Yang, Jiejing (1); Yu, Lei (1); Ma, Chunhui (1); Zhang, Qianbing (1)
Author affiliation:(1) College of Animal Science and Technology, Shihezi University, Shihezi, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:128-137
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drip irrigation is being effectively used for alfalfa production in arid northwest China. The objectives of this paper were: i) to compare the effects of flood and drip irrigation on the spatial distribution of water and salt; ii) to compare effects of biomass, spatial distribution and dynamics of fine roots of alfalfa on the movement of water and salt in the soil profile under flood and drip irrigation. From May to October 2012, the plot experiments were carried out in Xinjiang Province. Flood irrigation (irrigation quantity is 4 600 m<sup>3</sup>/hm<sup>2</sup>) and drip irrigation treatments were set up (irrigation quantity is 4 200 m<sup>3</sup>/hm<sup>2</sup>), alfalfa planted in wide-narrow row plantation with a distance of 15 cm 30 cm 15 cm between rows. The results showed that soil water in the flood irrigation treatment was concentrated in the upper 15 cm of the soil profile. Furthermore, the soil water content was uniformly distributed across the plots, ranging between 19.5% and 20.5%. In the drip irrigation plots, soil moisture was concentrated in the upper 40 cm of the soil profile and within 30 cm on either side of the emitter of drip irrigation tapes, and the soil water content ranged between 18.0% and 20.0%. Flood irrigation leached salt to below the 30 cm depth. As a result, salinity in the 0-30 cm depth decreased from 0.4-0.5 mS/cm to 0.3 mS/cm or less. Drip irrigation significantly reduced the salinity to 0.2 mS/cm in the root zone. The narrower-deeper-type soil wetting pattern and desalted zone were formed in drip irrigation and alfalfa planted in this area has higher water content and lower salt content than flood irrigation, therefore drip irrigation provides excellent soil environment for alfalfa growth. While wider-shallower-type soil wetting pattern and desalted zone were formed in flood irrigation. Compared with the flood irrigation treatment, fine roots in the drip irrigation treatment were concentrated in the 0-50 cm depth and near to the emitter of drip irrigation tapes. Total fine roots biomass was greater in the drip irrigation treatment (212 g/m<sup>2</sup>) than that in the flood irrigation treatment (198 g/m<sup>2</sup>). Fine root biomass fluctuated during the growing season because of regrowth of alfalfa and harvest schedule. Fine root biomass ranged from 193 to 244 g/m<sup>2</sup> in the drip irrigation treatment and from 183 g/m<sup>2</sup> to 219 g/m<sup>2</sup> in the flood irrigation treatment. During the entire growing period, live fine root biomass was greater in the drip irrigation treatment than that in the flood irrigation treatment. Live fine root biomass was fluctuated in flood and drip irrigation obviously, ranged from 73 to 139 g/m<sup>2</sup> and 97 to 144 g/m<sup>2</sup> respectively, During the early growth stages (from 2nd April to 18th July), the biomass of dead fine roots changed more smoothly in the drip irrigation treatment (ranged from 93 to 101 g/m<sup>2</sup>) than in the flood irrigation treatment(ranged from 96 to 125 g/m<sup>2</sup>), but the biomass of dead fine roots in drip irrigation was fluctuated from 72 to 102 g/m<sup>2</sup> after 18th July. Biomasses of live and dead fine roots both changed continuously because of rapid turnover of fine roots, first increasing (growth), then decreasing (death and decomposition), and then increasing again (regrowth). The results indicated that drip irrigation provide suitable soil condition for alfalfa growth by redistribution of soil water and salt, and the model of the wide-narrow row plantation with a distance of 15 cm 30 cm 15 cm between rows and drip irrigation is the optimal cultivation pattern of alfalfa. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Irrigation
Controlled terms:Biomass - Cultivation - Ecology - Floods - Salts - Soil moisture - Soil surveys - Soils - Spatial distribution - Water content - Wetting
Uncontrolled terms:Distribution of water - Drip irrigated alfalfa - Fine roots - Fine-root biomass - Harvest schedule - Soil environment - Soil water content - Soil wetting pattern
Classification code:444 Water Resources - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 804.1 Organic Compounds - 821.3 Agricultural Methods - 821.5 Agricultural Wastes - 914.1 Accidents and Accident Prevention - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2014.23.017
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 27>
Accession number:20150400457751
Title:Preparation of fresh rice noodles using rice prepared by tempering moisture and semi-dry milling method and determination of its quality
Authors:Tong, Litao (1); Gao, Xiaoxu (1); Wang, Li (2); Yi, Cuiping (3); Zhou, Sumei (1)
Author affiliation:(1) Institute of Agro-Products Processing Science and Technology, Chinese Academy of Agricultural Sciences/Key Laboratory of Agro-Products Processing, Ministry of Agriculture, Beijing, China; (2) State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, China; (3) School of Chemical and Biomedical Engineering, Changsha University of Science and Technology, Changsha, China
Corresponding author:Zhou, Sumei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:332-338
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditionally, wet-milling of rice followed by an overnight soaking in water is commonly used as a processing for making rice noodles. However, the long soaking time resulted in bacterial growth on rice, leading to degradation in product quality. Therefore, the dry-milling method is used to break rice kernel, but the dry-milling can create more heat and mechanical damage which can lead to an increased damage of rice starch granules. As such, dry-milled rice flour exhibits a higher degree of starch damage compared to the wet-milled rice flour. Therefore, the quality of rice noodles produced from dry-milled rice flour is not acceptable by consumers despite the fact that dry-milling improved the safety and stability of rice products. In order to minimize the adverse effects of dry-milling on characteristics of rice flour and cooking qualities of rice noodles, the objective of this study was on developing a new process of semi-dry milling. To investigate the effect of semi-dry milling on rice flours characteristics and fresh rice noodles quality, the rice with 28% and 30% tempering moistures were milled by cyclone mill and Buller mill. Whiteness, gel properties and pasting properties of rice flours were analyzed, and then textural properties, cooking properties and sensory quality of fresh rice noodles were determined. The results showed that tempering moisture and milling equipments can affect rice flours qualities significantly. Milling rice with 28% and 30% tempering moisture can minimize the granules damage by machine and excess heat generated during milling. Flours whiteness of rice with 28% and 30% tempering moisture milled by Buller mill were significantly higher than wet-milled flours (P<0.05), but the use of cyclone milling on rice with 30% tempering moisture had a similar whiteness with wet-milled flours. Among the four kinds of semi-dry milled flour samples, the gel from cyclone-milled rice flour (30% tempering moisture) showed the highest hardness (3.45 N/cm<sup>2</sup>), which had no significant difference with wet-milled flour (P>0.05), whereas Buller semi-dry milled flours showed lower value than wet-milled flour (P<0.05). The pasting properties showed that tempering moisture and milling equipments did not affect the pasting temperature. Higher peak viscosity was observed in wet-milled rice flour, and lower one was observed in Buller -milled rice flour (30% tempering moisture) compared to dry-milled rice flour, the breakdown of flour samples milled from rice with 30% tempering moisture were lower than the wet-milled flour (P < 0.05), and lower value of setback was observed in Buller -milled rice flour (30% tempering moisture), which had no significant difference with the wet milled flour (P > 0.05), but cyclone-milled rice flour (30% tempering moisture) still had higher setback than the dry-milled rice flour. Based on the comparison of rice flour characteristics between semi-dry milled flours and wet-milled flour, the use of cyclone milling on rice with 30% tempering moisture was selected to be the best method. Compared to wet-milling, rice noodles produced by dry-milling can not be used for texture measurement due to its high broken rate, and it had the worst cooking qualities and sensory (visual and taste) evaluation. However the quality of rice noodles produced from cyclone-milled rice flour (30% tempering moisture) were significantly improved. The texture hardness was 35.10 N/cm<sup>2</sup>, the elasticity was 0.97, which were softer and more elastic than the wet-milling produced rice noodles. Moreover semi-dry milling method significantly affected the cooking loss and turbidity of rice noodles, which was 7.51% and 0.40 for the noodles prepared with cyclone-milled rice flour (30% tempering moisture), sensory evaluation was higher than the dry-milling produced rice noodles (P < 0.05), and there were no significant differences of cooking properties and sensory qualities between them (P > 0.05). Those results showed that the semi-dry milling can minimize the damage caused by mechanical forces and heat during milling. The method also reduced water use and the risk of microbial contamination in the traditional wet milling. Therefore, the semi-dry milling of rice with higher tempering moisture, such as cyclone-milled rice flour (30% tempering moisture), can be used to replace the wet-milling for industrial production, and the process can provide good rice noodles quality similar to or better than the traditional wet milling method but with low water usage and low risk of microorganism contamination. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Milling (machining)
Controlled terms:Grain (agricultural product) - Granulation - Hardness - Moisture - Moisture control - Moisture determination - Processing - Quality control - Sensory perception - Starch - Storms - Tempering - Textures - Water quality
Uncontrolled terms:Dry milling - Industrial production - Microbial contamination - Pasting temperature - Quality evaluation - Rice flour - Safety and stabilities - Textural properties
Classification code:421 Strength of Building Materials; Mechanical Properties - 443.1 Atmospheric Properties - 443.3 Precipitation - 453.2 Water Pollution Control - 461.4 Ergonomics and Human Factors Engineering - 537.1 Heat Treatment Processes - 604.2 Machining Operations - 802.3 Chemical Operations - 804.1 Organic Compounds - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 913.4 Manufacturing - 933 Solid State Physics - 944.2 Moisture Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.23.042
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 28>
Accession number:20150400457723
Title:Calculation of area target evapotranspiration in yellow river basin and evaluation of water resource allocation
Authors:Feng, Feng (1); Dong, Guotao (3); Zhang, Wenge (3)
Author affiliation:(1) Water Resources Research Center, Yellow River Conservancy Technical Institute, Kaifeng, China; (2) Department of Water Conservancy, Tsinghua University, Beijing, China; (3) Yellow River Institute of Hydraulic Research, Zhengzhou, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:101-111
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Aiming at target ET calculation in water resources management model based on R - ET (runoff-evapotranspiration) in Yellow River basin, the paper puts forward calculation method and process. The first step is to formulate scheme set according to water resources in research area. The second step is to calculate the target ET of different sub item using the method such as the distributed hydrologic model, remote sensing estimation model, and the water use quota method. The third step is to evaluate each scheme based on the principle of sustainability, fairness and effectiveness, and to find the best scheme. Ordos is taken as the case study and five schemes were calculated in this paper. Scheme 1 is present situation of water resources utilization, and the target ET is 468.79 mm. Scheme 2 is increasing diverting water from the Yellow River, and the target ET is 450.89 mm. Scheme 3 is decreasing the ground water, and the target ET is 432.95 mm. Scheme 4 is to reduce diverting water from the Yellow River, and the target ET is 406.11 mm. Scheme 5 is a saving water plan, the target ET is 383.27 mm. Then, the scheme 5 is the optimal solutions and recommendations according to comprehensive evaluation. The comparison between Scheme 1 and 5 showed that, with the development of population, economy and society, target ET reduced gradually with the high water-saving measures. The proportion of target ET in cultivated land declined, because water consumption of cultivated land reduced. The proportion of residential and industrial land target ET increased due to the economic development. The second and third industry water demand and ecological water use will increase at the same time. In order to guarantee reliability and accuracy of the area target ET, calculation results of distributed hydrological model and the remote sensing estimation method verified the validity. Two methods calculation error of the area actual ET value is 0.78% and 1.22%, respectively. Target ET determination and evaluation in this study provide references for the next step to implement R - ET water management in the Yellow River basin. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Water resources
Controlled terms:Economics - Evapotranspiration - Groundwater - Industrial economics - Land use - Remote sensing - Rivers - Water conservation - Water management - Water supply - Watersheds
Uncontrolled terms:Distributed hydrologic model - Distributed hydrological model - Ordos - Remote sensing estimations - Scheme evaluation - Water resources management - Water resources utilizations - Yellow River basin
Classification code:403 Urban and Regional Planning and Development - 444 Water Resources - 446.1 Water Supply Systems - 731.1 Control Systems - 911.2 Industrial Economics
DOI:10.3969/j.issn.1002-6819.2014.23.014
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 29>
Accession number:20150400457729
Title:Factors affecting spectral characteristics of typical takyr solonetzs
Authors:Zhang, Junhua (1); Ma, Tiancheng (2); Jia, Keli (3)
Author affiliation:(1) Center of New Technology Application and Research, Ningxia University, Yinchuan, China; (2) School of Physics Electrical Information Engineering, Ningxia University, Yinchuan, China; (3) College of Resources and Environment, Ningxia University, Yinchuan, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:158-165
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Spectral reflectance of soil can be used to accurately predict the degree of soil salinization, however, it has not been widely used in the Typical Takyr Solonetzs of northern Yinchuan city, Ningxia Province. Although it has been reported that soil spectral reflectance can be affected by multiple factors, it is still lack of enough evidences to test which factor plays main role in soil spectral reflectance. Therefore, we conducted an experiment using several treatments in Typical Takyr Solonetzs of northern Yinchuan city, including alkalinity degree (extremely alkaline soil, strongly alkaline soil, moderately alkaline soil, slightly alkaline soil, and non-alkaline soil), water content (3.93%, 11.71%, 19.24%, 22.33%, 25.39% and 26.45%), particle size (3 mm, 2 mm, 1 mm, 0.25 mm and 0.1 mm) and roughness (coarse and smooth). We measured soil spectral reflectance both in field and in laboratory under different treatments. By analyzing these variables, we wanted to systematically determine how these factors affect spectral reflectance of Takyr Solonetzs. The results showed that reflectance in the top soil (0-20 cm) observed in the field had a positive relationship with the degree of soil alkalinity, indicating that the soil with the most serious alkalinity had the highest reflectance. In the wavelength range of 450-925 nm, the reflectance of extremely alkaline soil was 7.36%, 23.18%, 32.10% and 39.97% respectively higher than those of strongly alkaline soil, moderately alkaline soil, slightly soil and non-alkaline soil. Reflectance at 765 nm, 945 nm and 974 nm was sensitive to diagnose the alkalinity of Takyr Solonetzs. Soil reflectance can be significantly decreased by pretreatment (including air dried, ground and sifted before spectral measurement) in laboratory. The reflectance of extremely alkaline soil, strongly alkaline soil, moderately alkaline soil and slightly alkaline soil measured in the field were 0.1645, 0.1312, 0.0575 and 0.0246 higher than that with pretreatment. Spectral reflectance showed a decreasing trend with the increase of soil water content. However, it increased gradually when soil water content was over 22.85% (field capacity). Spectral reflectance in the soil with 26.45% of water content increased by 39.68% and 19.79% than those with 22.33% and 25.39% of water content, respectively. We also observed that particle size of soil sample had obvious impact on soil reflectance. When the particle size was smaller than 0.25 mm, the difference of reflectance between 0.25mm and 0.1mm were smaller than the particle size with 3 mm, 2 mm and 1 mm. The reflectance of soil particle size below 0.10 mm were 30.39%, 28.62%, 23.87% and 8.10% higher than 3 mm, 2 mm, 1 mm and 0.25 mm of particle size, and the bigger particle size had a special twin - peak phenomenon. Surface roughness had a negative effect on soil reflectance. We concluded that salinity degree can significantly influenced the field spectral reflectance of Takyr Solonetzs; the soil water content was the major factor that influenced the spectral reflectance of strongly alkaline soil by pretreatment, and there were little influences of the salinity degree and surface roughness on the soil spectral reflectance. Our results will be helpful for in situ prediction of the degree of soil alkalinity of Takyr Solonetzs. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Soil surveys
Controlled terms:Particle size - Particle size analysis - pH - Reflection - Salts - Soil moisture - Soils - Spectrum analysis - Surface roughness - Water content
Uncontrolled terms:Different treatments - Effect factors - Field spectra - Soil spectral reflectance - Spectral characteristics - Spectral measurement - Spectral reflectances - Takyr solonetzs
Classification code:444 Water Resources - 483.1 Soils and Soil Mechanics - 711 Electromagnetic Waves - 801.1 Chemistry, General - 804.1 Organic Compounds - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.23.020
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 30>
Accession number:20150400457734
Title:Design and experiment for crop growth information monitoring instrument based on active light source
Authors:Lu, Shaolin (1); Ni, Jun (1); Cao, Weixing (1); Yao, Xia (1); Zhu, Yan (1)
Author affiliation:(1) National Engineering and Technology Center for Information Agriculture, Nanjing Agricultural University, Nanjing, China
Corresponding author:Zhu, Yan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:199-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Spectral remote sensing instrument is widely used for land-use management, precision agriculture, and crop monitoring. However, these spectral sensors have some problems with expensive, complex operation, restricted by the intellectual property rights and environmental impact. In order to resolve monitoring the field growth information with characteristics of all-weather, real-time, fast and non-destructive, a crop growth information monitoring instrument based on active light source was developed based on crop growth spectroscopy. The instrument composed of the crop growth information sensor system, the control system and other units. can acquire the vegetation spectral index value of normalized differential vegetation index, ratio vegetation index, difference vegetation index and renormalized difference vegetative index are quickly and accurately. And these factors are the real-time indicators for the growth of the inversion field crops. The crop growth information sensor system includes two sensing channels of 730nm and 810nm. Each sensing channel includes light source unit and spectrum signal acquisition unit, and the light source unit sends spectrum signals of modulation to radiate crop canopy and spectrum signal acquisition unit receives information reflected for removing the sun light from crop canopy. The reflection and vegetation spectral index value of normalized differential vegetation index, ratio vegetation index, difference vegetation index and renormalized difference vegetative index were calculated. The light source unit is composed of square-wave generator, LED constant current drive circuit and optical system for light source, which exposure to crop canopy. By using active light modulation modulating technology and special optical and circuit design, the spectral information is switched to voltage information, which is easy to be obtained by hardware selection filter technology. The modulation frequency is 1 kHz. The spectrum signal acquisition unit is made up of optical system for spectrum signal acquisition, photoelectric detector circuit, the first level amplifier circuit, band filter circuit, the second level amplifier circuit and signal detector circuit, which can abstract characteristic spectrum information. The control system uses ATmega32 microprocessor as core, including key input, liquid crystal display(LCD), SD card storage, temperature and humidity sensors, sound and light alerts and power supply modules. The modularized structure is used in the design of software system based on C language, the main function of the temperature and humidity of the acquisition, supply power collection, low voltage alarm, spectral reflectance capture and storage, crop vegetation spectral index of conversion, liquid crystal display(LCD), key input and so on. The monitor can be better to remove the external interference caused by the sun in measurement process, so as to realize accurate measurement in vegetation spectral index of crop canopy. The stability experiments showed that the monitor had good stability of anti-light interference, and the output volt of monitor is almost constant, and the stability standard deviation(SD) of 730 nm and 810 nm were 1.05% and 0.47%. Wheat experiments showed that the value of vegetation spectral index measured by the monitor had significant correlation with normalized differential vegetation index, ratio vegetation index, difference vegetation index and renormalized difference vegetative index with the coefficients of determination R<sup>2</sup> were 0.7017, 0.7071, 0.8178, 0.7804, and the root mean square error(RMSE) were 0.05362, 0.2118, 0.03434, 0.04182, respectively. Finally, the monitor has advantages as good stability, strong anti-interference capacity and easy to operate, can achieve the monitoring requirements of the field crop growth information. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Light emitting diodes
Controlled terms:C (programming language) - Control systems - Crops - Crystal structure - Design - Detector circuits - Environmental impact - Growth (materials) - Humidity control - Information analysis - Integrated circuit manufacture - Intellectual property - Land use - Laws and legislation - Light sources - Liquid crystal displays - Mean square error - Mergers and acquisitions - Modulation - Monitoring - Optical systems - Remote sensing - Signal analysis - Signal processing - Square wave generators - Stability - Vegetation
Uncontrolled terms:Growth information - Intellectual property rights - Liquid crystal display(LCD) - Normalized differential vegetation indices - Remote sensing instruments - Temperature and humidities - Temperature and humidity sensor - Vegetation index
Classification code:402 Buildings and Towers - 403 Urban and Regional Planning and Development - 408 Structural Design - 454.2 Environmental Impact and Protection - 713.3 Modulators, Demodulators, Limiters, Discriminators, Mixers - 714.2 Semiconductor Devices and Integrated Circuits - 715.1 Electronic Equipment, non-communication - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 723.1.1 Computer Programming Languages - 731.1 Control Systems - 741.3 Optical Devices and Systems - 801 Chemistry - 801.4 Physical Chemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 902.3 Legal Aspects - 903.1 Information Sources and Analysis - 912 Industrial Engineering and Management - 931 Classical Physics; Quantum Theory; Relativity - 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 - 951 Materials Science - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2014.23.025
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 31>
Accession number:20150400457749
Title:Determination and visualization of fat contents in salmon fillets based on visible and near-infrared hyperspectral imagery
Authors:Zhu, Fengle (1); Peng, Jiyu (1); Gao, Junfeng (1); Zhao, Yanru (1); Yu, Keqiang (1); He, Yong (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China; (2) Key Laboratory of Equipment and Informatization in Environment Controlled Agriculture, Ministry of Agriculture, Hangzhou, China
Corresponding author:He, Yong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:314-323
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an important quality criterion in Atlantic salmon (Salmo salar), fat distributes heterogeneously throughout the whole salmon fillets. In this study, visible and near-infrared hyperspectral imaging was employed to determine the spatial distribution of fat in salmon fillets non-invasively and rapidly. One hundred cubed samples were cut out from different locations of different whole fillets to maximize fat content variation. After acquiring hyperspectral images with two systems operated in visible and short-wave near-infrared (Vis/SWNIR, 400-1100 nm) and near-infrared (NIR, 900-1700 nm) ranges, salmon samples were subjected to standard chemical analysis to measure their reference fat contents. Region of interests (ROI) was identified to isolate fish from the background in hyperspectral images, and the averaged reflectance spectra of the ROI image were extracted for all samples. Due to the low signal-to-noise ratio in the starting and ending spectral regions of both systems, only 740 Vis/SWNIR bands (459-1056 nm) and 151 NIR bands (947-1666 nm) were applied. The total samples were randomly divided into calibration set of 65 samples and prediction set of 35 samples. Then the extracted spectral variables with full wavelengths in two spectral sets for calibration samples were correlated with their corresponding reference fat contents using partial least squares regression (PLSR) and least-squares support vector machines (LS-SVM), respectively. And fat values for samples in the prediction set were predicted using the established models. Though good prediction results were achieved using full wavelengths, some redundant information exist among contiguous wavelengths due to the high degree of dimensionality in hyperspectral images. Competitive adaptive reweighted sampling (CARS) algorithm was employed to select effective wavelengths (EWs) for two spectral sets. Sixteen EWs of 468, 479, 728, 734, 785, 822, 863, 890, 895, 899, 920, 978, 1005, 1033, 1040, 1051 nm were selected in Vis/SWNIR spectral region, and fifteen wavelengths of 975, 995, 1023, 1047, 1095, 1124, 1167, 1210, 1273, 1316, 1354, 1368, 1575, 1632, 1661 nm were selected in NIR region. Then calibration models of EWs-PLSR and EWs-LS-SVM were established on the basis of the selected EWs of two spectral sets respectively. Improved performances for fat determination were observed for EWs-based models compared with full-spectrum models while the computational cost reduced greatly. And the linear EWs-PLSR model with NIR spectra was identified as the optimal model for fat prediction with determination coefficient of prediction (R<sup>2</sup>p) of 0.92, root mean square error of prediction (RMSEP) of 0.92%, and residual predictive deviation (RPD) for prediction of 3. 50. Finally, the EWs-PLSR model was transferred to all pixels in the NIR hyperspectral images to predict their fat values for visualizing fat distribution in salmon samples. Fat distribution images for two whole salmon fillets were also generated to further explore the feasibility of hyperspectral imaging combined with the optimal model for fat visualization in whole fillets. Images like these could not only enable producers to perform proper sorting and cutting based on certain concentration thresholds but also benefit consumers to make the most appropriate decision when choosing salmon products. The overall results indicated that hyperspectral imaging coupled with chemometrics have potential for the determination and visualization of fat in salmon fillets. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Infrared devices
Controlled terms:Calibration - Chemical analysis - Extraction - Flow visualization - Forecasting - Least squares approximations - Mean square error - Models - Near infrared spectroscopy - Principal component analysis - Signal to noise ratio - Spectroscopy - Support vector machines - Visualization
Uncontrolled terms:Determination coefficients - Fat - Hyperspectral Imaging - Least squares support vector machines - Partial least squares regressions (PLSR) - Root-mean-square error of predictions - Salmon - Visible and near infrared
Classification code:631.1 Fluid Flow, General - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 741.3 Optical Devices and Systems - 801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 902.1 Engineering Graphics - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.23.040
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 32>
Accession number:20150400457737
Title:Improving communication quality of internet of things for pelagic fishing vessel by blended fog computing and cloud computing
Authors:Yang, Jinsong (1); Yu, Lijuan (1); Ling, Peiliang (1); Chen, Chengming (2); Xia, Jun (1)
Author affiliation:(1) College of Mechanical Engineering, Tongji University, Shanghai, China; (2) College of Engineering, Shanghai Ocean University, Shanghai, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:224-231
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The communication bandwidth from pelagic fishing vessel to shore was unable to cope with the increasing needs of smart devices and sensors on vessel. Fog computing and cloud computing were combined to solve this problem effectively in operating system of pelagic fishing vessel. Cloud computing could be used as the basic framework of system. Fog computing could be used as model in the local area network and sensor network on vessel. This mixed computing architectures could effectively play the advantages of each other and have a complementary effect. In research, cloud computing was taken as basic framework of operating system of pelagic fishing vessel, and service-oriented architecture service component was used to provide a reliable and safe data storage center, which could reduce the equipment requirements for client and share data and applications between different devices. There were two sources for service components. One part came from the encapsulation of original system function and was released through the network via the standards such as simple object access protocol, web services description language, universal description discovery and integration, et al.. It could effectively protect the investment. Other parts were new service components facing new requirements, which were packaged by extensible web service and supported open, dynamic interoperability model. The standard cloud computing framework increased the demand for network bandwidth. For the data volume of firmware update and message sent by sensors occupied larger proportion of communications from vessel to shore, this paper also studied equipment firmware distribution mechanism and shipboard sensor network computation model based on fog computing in order to reduce ship shore data traffic. With the aid of computing and storage capacity of shipboard equipment, the firmware distribution mechanism changed the traditional way that each device got update files from the cloud directly, pushed and updated the firmware between smart devices and sensors in local area network of vessel. This paper also studied shipboard sensor network computation model based on fog computing. For shore-based command center just was focused on changes or change tendency of message sent by sensors, the system could reduce the amount of data transmission by send filtered date only. Smart devices with computing and storage capacity could be used to select and calculate message data before they were sent to cloud by sensors in vessel, which reduced the amount of communication with high monitoring accuracy. Practice has proved that cloud-fog mixed computing architectures could not only ensure interactive integration of information from vessel to shore, but also significantly reduce the requirement for data communication bandwidth and the network traffic. During the practice period, from March 15 to May 31 in 2014, the data volume of firmware update file of smart devices and sensors was 250.905 MB, the actual firmware update communication flow was 37.175 MB. Firmware update data decreased to 14.81% of the traditional architecture. At the same time, the data volume of cumulative message produced by 27 temperature sensors was 571.63 MB, and the actual data volume of message sent from vessel to shore was 27.16 MB after selection and calculation, so message data volume reduced to 4.75%. In this period, about $7500 were saved. According to this calculation, each boat can save communication cost by $36 000 each year and the costs of communication were markedly reduced. The empirical research obtained obvious effect on a pelagic fishing vessel named Kaifu. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Fishing vessels
Controlled terms:Bandwidth - Cloud computing - Computation theory - Data communication equipment - Data handling - Data processing - Data reduction - Digital storage - Distributed computer systems - Equipment - Firmware - Fisheries - Fog - Information services - Internet - Internet of things - Internet protocols - Interoperability - Local area networks - Network architecture - Sensors - Service oriented architecture (SOA) - Ships - Social networking (online) - Transportation - Web services - Websites
Uncontrolled terms:Communication bandwidth - Computing architecture - Distribution mechanism - Dynamic interoperability - Simple object access protocols - Traditional architecture - Universal description discovery and integration - Web Services Description Language
Classification code:431 Air Transportation - 432 Highway Transportation - 433 Railroad Transportation - 434 Waterway Transportation - 443.1 Atmospheric Properties - 471.5 Sea as Source of Minerals and Food - 671 Naval Architecture - 672 Naval Vessels - 674 Small Craft and Other Marine Craft - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 722.1 Data Storage, Equipment and Techniques - 722.4 Digital Computers and Systems - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 801 Chemistry - 901 Engineering Profession - 903.4 Information Services - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.23.028
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 33>
Accession number:20150400457716
Title:Transversal vibration analysis of resonance condition and frequency for orchard chain ropeway system
Authors:Li, Jun (1); Li, Xueping (1); Yang, Zhou (1); Hong, Tiansheng (1); Xue, Kunpeng (1); Li, Wei (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou, China
Corresponding author:Yang, Zhou
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:50-57
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To suppress the transverse vibration of an axially moving chain system with concentrated inertial masses in hilly orchard, the important factors affecting frequency characteristic of moving chain and their interaction are required to be studied. Based on the string theory and dynamics of chain transmission, the differential equation of transverse vibration was developed in the Laplace domain and the critical transport velocity was obtained in this paper. The stable condition for transport velocity corresponding to resonance was determined by considering the polygon effect causing speed variation when the moving chain link engaging with supporting end. With solutions for the second-order homogeneous partial differential equation, the effects of initial tension, transport velocity and load mass on the frequency of transverse vibration were numerically and experimentally analyzed. The difference between measured data and calculated data yielded values from 1.4% to 27.6% for various transport velocities, from 6.1% to 14.2% for various load masses, and from 14.7% to 24.3% for various initial tensions. The results show that the frequency of transverse vibration of axially moving chain increases with the increase in initial tension. The negative effect of transport velocity and load mass on vibration frequency in the case of forced nonlinear vibration is found. The proposed differential equation is proved valid to predict the effects of operation parameters on vibration frequency. It is conformed that this approach to transverse vibration of an axially moving chain can be used for parameter optimization under a certain constraint condition. The solution provides the theoretical basis for the vibration analysis and stability control of moving chain by consideration of wind-induced and rain-induced effects. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Vibration analysis
Controlled terms:Agricultural machinery - Chains - Differential equations - Farms - Orchards - Transportation - Velocity
Uncontrolled terms:Frequency - Frequency characteristic - Homogeneous partial differential equations - Non-linear vibrations - Parameter optimization - Transversal vibration - Transverse vibrations - Vibrations
Classification code:431 Air Transportation - 432 Highway Transportation - 433 Railroad Transportation - 434 Waterway Transportation - 602.1 Mechanical Drives - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.2 Calculus - 931.1 Mechanics - 943.2 Mechanical Variables Measurements
DOI:10.3969/j.issn.1002-6819.2014.23.007
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 34>
Accession number:20150400457742
Title:Characteristics of greenhouse soil N<inf>2</inf>O emissions in cucumber-tomato rotation system under different nitrogen conditions
Authors:Li, Yinkun (1); Wu, Xueping (2); Guo, Wenzhong (1); Xue, Xuzhang (1)
Author affiliation:(1) Beijing Research Center of Intelligent Equipment for Agriculture, Beijing, China; (2) Institute of Agricultural Resource and Regional Planning, Chinese Academy of Agriculture Sciences, Beijing, China
Corresponding author:Wu, Xueping
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:260-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nitrous oxide (N<inf>2</inf>O) is one of the most important greenhouse gases contributing to global warming and depletion of the stratospheric ozone layer. Arable land with nitrogen fertilizer application is one of the major sources of N<inf>2</inf>O emission, and the nitrogen fertilizer rate in greenhouse vegetable field is higher than that in farmland in China. However, few studies have measured N<inf>2</inf>O emissions from solar greenhouse vegetable fields, especially in cucumber-tomato rotation system. In order to identify the annual dynamic of greenhouse soil N<inf>2</inf>O emissions and investigate the impacts of nitrogen application rate on N<inf>2</inf>O emissions, the closed static chambers method was used in cucumber-tomato rotation system in greenhouse in the Northern Plain of China. The study included four nitrogen treatments, traditional nitrogen rate (cucumber, 1200 kg/hm<sup>2</sup>; tomato, 900 kg/hm<sup>2</sup>), reduced by 25% (cucumber, 900 kg/hm<sup>2</sup>; tomato, 675 kg/hm<sup>2</sup>) and 50% (cucumber, 600 kg/hm<sup>2</sup>; tomato, 450 kg/hm<sup>2</sup>), and a control (no N application). Results showed that temperature was an important factor affecting the N<inf>2</inf>O emission intensity in greenhouse. The highest of N<inf>2</inf>O fluxes was 818.4 μg/ (m<sup>2</sup>·h) occurred from April to Oct., when the average of air temperature and soil temperature were 27.4 and 26.1, respectively. While N<inf>2</inf>O fluxes was 464.5 μg/(m<sup>2</sup>·h) occurred from Feb. to March (average air temperature=15.1, average soil temperature=15.0) and Nov. to Dec. (average air temperature =14.7 and average soil temperature=13.7), this was significantly lower than that from April to Oct. Compared to the N<inf>2</inf>O flux from April to Oct., there was a 43.2% reduction in N<inf>2</inf>O fluxes from Feb. to March and Nov. to Dec. The peak of N<inf>2</inf>O emissions occurred in the first five days after topdressing of urea. The N<inf>2</inf>O emission occurred most in the first seven days after urea topdressing, which accounted for 64.7%-67.8% of total emissions during the 271 d study period. Soil moisture was not a limiting factor on N<inf>2</inf>O fluxes in greenhouse cucumber and tomato fields, because the soil water content was suitable (water filled pore space of 40.0% to 66.6%) and fertilization was usually followed by irrigation in the experiment. N<inf>2</inf>O emission increased drastically with an increasing in soil nitrate content after nitrogen application, and there was an exponential relationship between N<inf>2</inf>O emission fluxes and 0-10 cm soil nitrate content (P<0.01). Compared to traditional nitrogen rate, N<inf>2</inf>O flux peaks reduced by 40.4% and 59.3% when the nitrogen rate was decreased by 25% and 50%, respectively. The cumulative N<inf>2</inf>O emissions were 0.99-9.92 kg/hm<sup>2</sup> in the cucumber-tomato rotation system, of which 50.5%-56.9% was from cucumber growing season. Taking N<inf>2</inf>O emissions from the N0 treatment as the background emissions, the annual N<inf>2</inf>O emission factors of nitrogen input were 0.29%-0.43% during the cucumber and tomato growth period, increasing gradually with the nitrogen application rates. About 75.6% to 90.0% of the N<inf>2</inf>O emissions were caused by nitrogen application in greenhouse vegetable fields. Less N<inf>2</inf>O emissions were produced when less nitrogen fertilizer was used. Compared to the traditional nitrogen rate treatment, cumulative N<inf>2</inf>O emissions of minus 25% and 50% nitrogen compared to traditional treatment were reduced by 40.4% and 59.3%. At the same time, the decreased nitrogen rate increased the total yield by 4. 8% and 7.4%. In summary, for present solar greenhouse vegetable production in the North China Plain, appropriate reduction of nitrogen application rate can significantly reduce the N<inf>2</inf>O emissions without any negative effect on yield. The research provides a reference for nitrogen management for greenhouse vegetable production and fills the information gap for N<inf>2</inf>O emission from greenhouse under current management practice in China. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Nitrogen fertilizers
Controlled terms:Atmospheric temperature - Fertilizers - Fruits - Global warming - Greenhouse effect - Greenhouse gases - Greenhouses - Landforms - Metabolism - Nitrates - Nitrogen - Nitrogen oxides - Ozone layer - Rotation - Soil moisture - Soils - Temperature - Urea - Vegetables - Water content
Uncontrolled terms:Emissions control - Nitrate nitrogen - Nitrogen application rates - Nitrogen fertilizer rate - Nitrogen levels - Solar greenhouse - Stratospheric ozone layers - Water-filled pore space
Classification code:443.1 Atmospheric Properties - 444 Water Resources - 461.9 Biology - 481.1 Geology - 483.1 Soils and Soil Mechanics - 601.1 Mechanical Devices - 641.1 Thermodynamics - 804 Chemical Products Generally - 821.4 Agricultural Products - 821.6 Farm Buildings and Other Structures
DOI:10.3969/j.issn.1002-6819.2014.23.033
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 35>
Accession number:20150400457741
Title:Water treatment performance of O<inf>3</inf>/UV reaction system in recirculating aquaculture systems
Authors:Guan, Chongwu (1); Yang, Jing (1); Shan, Jianjun (1); Zhang, Haigeng (1); Liu, Huang (1); Wang, Xin (2)
Author affiliation:(1) Key Laboratory of Fishery Equipment and Engineering, Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China; (2) School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai, China
Corresponding author:Yang, Jing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:253-259
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to improve the water treatment performance of ozone in recirculating aquaculture systems, and enhance its application safety in the field of aquaculture, the O<inf>3</inf>/UV integration reaction system were designed. The reaction system was mainly composed of ozone addition dissolved area, ultraviolet catalytic reaction area, stay reaction area. The system was 1 250 mm of high, 750 mm in diameter, and the ultraviolet catalytic reaction was 400 mm in diameter. The working principle of system was that using static mixer way to add ozone, which could dissolve wastewater high efficiency and low energy consumption in ozone addition dissolved area. The wastewater with not completely dissolved ozone bottom up entered to ultraviolet catalytic reaction area, which could generate two advantages. On one hand, under the ultraviolet catalysis, the stronger oxidizing of hydroxyl was produced in further reaction, accelerated the rate of degradation of organic matter, and enhanced the effect of disinfection sterilization. On the other hand, it could reduce the residual amount of ozone in cultivation water, which improved the safety of the device. After treating in ultraviolet catalytic reaction area, the wastewater enter into the reaction area, which the main purpose was to keep a certain residence time of wastewater, and to improve the purification effect of degradation of organic matter and the ammonia nitrogen removal. The relationship of the suitable ozone dosage and wastewater treatment capacity in the ozone additive dissolved area, the process parameters about the ratio of ultraviolet radiation dose and the influence factors of wastewater purification and disinfection sterilization were studied through the test method. The experimental results showed that: 1) Under the condition of meeting with a certain water of dissolved ozone concentration, it could improve ozone dissolution rate and utilization rate through using low ozone inlet flow rate and low water flow. When the wastewater flow was 5 m<sup>3</sup>/h and the ozone dosage was 8.17 g/h, the ozone dissolution rate was 82.7%, the concentration of ozone in wastewater was 1.53 mg/L and the ozone utilization rate was up to 97.7%. 2) It could improve the removal rate of ozone residual quantity in wastewater by means of increasing the number of UV and lamp power. The effect of performance improvements was more obvious through increasing the number of UV lamp. When the UV additive amount was 1 996 MJ/cm<sup>2</sup> and the residual ozone concentration of 1.36 mg/L of influent wastewater in this system, the removal rate of residual ozone could be up to 83.82%, which achieved low residual ozone in aquaculture water and ensured the safety of breeding biology. 3) Compared with using ozone separately, the removal rate of UV<inf>254</inf>, total organic carbon, chemical oxygen demand and water colour of this system were increased to 109.95%, 89.77%, 29.25% and 51.44%, respectively, and the sterilization removal rate could be more than 97%. The integration reaction system had the feature of disinfection sterilization of aquaculture wastewater, degradation of organic matter efficient, removing water colour and increasing dissolved oxygen, which showed a better wastewater treatment performance. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Chemicals removal (water treatment)
Controlled terms:Aquaculture - Biochemical oxygen demand - Biogeochemistry - Biological materials - Catalysis - Chemical oxygen demand - Denitrification - Disinfection - Dissolution - Dissolved oxygen - Energy utilization - Flow of water - Inlet flow - Nitrogen removal - Organic carbon - Organic compounds - Oxygen - Ozone - Ozone water treatment - Purification - Sterilization (cleaning) - Testing - Wastewater - Wastewater treatment - Water treatment
Uncontrolled terms:Advanced oxidation technology - Ammonia nitrogen removal - Organic matter removal - Reaction system - Recirculating aquaculture system - Residual ozone concentrations - Wastewater purification - Wastewater treatment capacity
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 444 Water Resources - 445 Water Treatment - 445.1 Water Treatment Techniques - 452.3 Industrial Wastes - 452.4 Industrial Wastes Treatment and Disposal - 461.2 Biological Materials and Tissue Engineering - 481.2 Geochemistry - 525.3 Energy Utilization - 631.1 Fluid Flow, General - 631.1.1 Liquid Dynamics - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.3 Agricultural Methods
DOI:10.3969/j.issn.1002-6819.2014.23.032
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 36>
Accession number:20150400457730
Title:Physiological and biochemical response characteristics of Leymus chinensis to saline-alkali stress
Authors:Liu, Binshuo (1); Kang, Chunli (1); Wang, Xin (1); Bao, Guozhang (1)
Author affiliation:(1) Key Laboratory of Groundwater Resources and Environment of the Ministry of Education, College of Environment and Resources, Jilin University, Changchun, China
Corresponding author:Bao, Guozhang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:166-173
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Salinization of grassland is one of the main causes of the degeneration of Leymus chinensis grassland in north-eastern part of China. In this study, we sampled L. chinensis as experimental materials, simulated in five soil stresses under different salinization gradient intensity (pH values were 7.61, 8.05, 8.33, 8.72, 9.37, the corresponding electrical conductivity were 0.109, 0.301, 0.438, 0.486, 0.591 dS/m) during a 120-day period from the beginning of spring to the end of fall. Then we measured ion content and transport capacity, osmotic adjustment of small organic molecules and the change of protective enzymatic activities to understand the range and the mechanism of L. chinensis adapting to saline-alkali stress. The results illustrated that with the increase of saline-alkali stress, superoxide dismutase (SOD) and betaine were accumulated to the maximum under moderate saline-alkaline stress A3. The content of Na<sup> </sup>, proline, malonaldehyde (MDA), organic acids (oxalic acid, citric acid, tartaric acid), catalase (CAT), peroxidase (POD), soluble protein and total soluble sugar showed a linear increase with the increase of saline-alkaline stress. However, the content of K<sup> </sup> and K<sup> </sup>/Na<sup> </sup> indicated a contrary tendency and the differences were also significant (P<0.05). Under the different levels of saline-alkali stress, the selective transportation index of K<sup> </sup> (ST<inf>K-Na</inf>) which was from rhizome to tiller had no significant difference between five groups (P>0.05). It showed that L. chinensis was able to still regulate K<sup> </sup>, and transport them from rhizome to leaf. Under the saline-alkali stress, a higher accumulation of K<sup> </sup>, betaine, organic acids and soluble protein in leaf was observed than did in rhizome. However, proline, MDA, protective enzyme (CAT, POD, SOD) and total soluble sugar in leaf were lower than the ones observed in rhizome. Under the saline-alkali stress, CAT activity was on the top among the protective enzymes ranging from 11121.74 to 213345.2 U/g, followed by POD from 538.94 to 1570.337 U/g, and SOD from 60.17 to 106.86 U/g. Under the saline-alkali stress, CAT had the strongest effect to the antioxidation of L. chinenesis, which was the most important to maintain the completion of cytoplasmic membrane. MDA increased largely along with the increase of saline-alkali stress, which indicated that the L. chinensis membrane had been damaged. The damage intensity of rhizome was more serious than the injuries of leaves. The accumulation of protective enzymes, proline and MDA helped rhizome to prevent membrane from peroxidation under saline-alkaline stress, and kept normal osmotic adjustment ability, through which, contributing to transporting K<sup> </sup> and other nutrients to the leaves. Under saline-alkali stress, the leaves of L. chinensis carried out osmotic adjustment mainly through accumulation of betaine and organic acids. Our results indicated that L. chinensis was likely to exert a series of adaptable response on its physiology by the different soil conditions varied in salinization gradients. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Plants (botany)
Controlled terms:Alkalinity - Antioxidants - Betaines - Biochemistry - Cell membranes - Enzymes - Organic acids - Osmosis - Oxalic acid - Oxygen - Physiological models - Physiology - Proteins - Salts - Soils
Uncontrolled terms:Antioxidant enzyme - Electrical conductivity - Experimental materials - Leymus chinensis - Osmotic adjustment - Selective transportation - Small organic molecules - Superoxide dismutases
Classification code:461 Bioengineering and Biology - 483.1 Soils and Soil Mechanics - 801.1 Chemistry, General - 801.2 Biochemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds
DOI:10.3969/j.issn.1002-6819.2014.23.021
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 37>
Accession number:20150400457717
Title:Effect of ridge-till and no-till mulching modes in Northeast China on soil physicochemical properties
Authors:Lin, Jing (1); Liu, Yanfen (1); Li, Baofa (1); Qian, Wei (1); Niu, Jinliang (1)
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang, China; (2) College of Mechanical and Electrical Engineering, Qingdao Agricultural University, Qingdao, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:58-64
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Conventional ridge tillage is the dominant patterns used in ridge zone in Northeast China at present. In order to achieve the conversation tillage in Northeast China, we investigated the conventional tillage demonstration area of three provinces in Northeast China, conducted the field experiment and analyzed of different samples for the purpose of analyzing the influence on soil physicochemical properties. Comparison results show that no-till mulching ridge pattern is better in satisfying the bed environmental requirements of corn seed germination: Soil temperature is above 10-12 in 5-10 cm depth soil lawyer; soil moisture content is above 13%; the requirement of soil compactness is the upper loose, the lower tight, and increase the content of soil organic matter (1.43g/kg) and N, P, K content of the soil are 22.32 mg/kg, 2.05 mg/kg and 3.11 mg/kg, respectively. But we also found that the height of ridge in no-till mulching zone (9.43-11.5 cm) is lower (3.57-6.5 cm) than that in conventional tillage zone(13-18 cm), it is not conducive to playing the advantages of ridge tillage. We suggest intensifying the innovative design of corn no-till planter, in order to solve the problems of overweight, flatten ridge and compaction furrow. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Soils
Controlled terms:Agricultural machinery - Agriculture - Biogeochemistry - Biological materials - Design - Moisture - Organic compounds - Seed - Soil moisture
Uncontrolled terms:Comparison result - Conventional ridge till - Conventional tillage - Environmental requirement - No-till - Shape parameters - Soil organic matters - Soil physico-chemical properties
Classification code:408 Structural Design - 461.2 Biological Materials and Tissue Engineering - 481.2 Geochemistry - 483.1 Soils and Soil Mechanics - 801.4 Physical Chemistry - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2014.23.008
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 38>
Accession number:20150400457728
Title:Dynamics of soil carbon and nitrogen stocks following afforestation in gully region of Loess Plateau, China
Authors:Liang, Aihua (1); Han, Xinhui (1); Zhao, Fazhu (1); Ren, Guangxin (1); Yang, Gaihe (1)
Author affiliation:(1) College of Agronomy, Northwest A&F University, Yangling, China
Corresponding author:Yang, Gaihe
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:148-157
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The effect of vegetation restoration on soil carbon (C) and nitrogen (N) stocks is an important consideration during the remediation of degraded soil. The temporal variation and distribution of C and N stocks in the soil profile were studied in areas with different types of vegetation restoration in the Zhifanggou catchment of China's Loess Plateau. In this area, the "Grain-for-Green" project (GFGP) encouraged landscape scale habitat restoration during the last decade. Results showed that afforestation of degraded cropland significantly promoted CO<inf>2</inf> sequestration and restored soil N availability, which consequently reduced N limitation and sustained C sequestration. Above a vegetation age threshold, i. e. 26 years, afforestation significantly improved the linear correlation relationship between soil organic C (SOC) and total N (TN) stocks in the 0~60 cm soil profile. This linear SOC-TN stock nexus decreased with increasing soil depth, and the potential of having improved SOC stock, TN stock and the ratio between them in deeper soil layers increased with increasing time after afforestation. Managed plantations provide superior CO<inf>2</inf> sequestration and improvement in the SOC-TN correlation at a relatively short period after afforestation when compared to natural restoration where vegetation is established by natural colonization. So these results indicate that the C sequestration sustainability of afforestation should be assessed at a long-term scale, and a relative great attention should be focused on deeper soil. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:40
Main heading:Soils
Controlled terms:Carbon - Carbon dioxide - Catchments - Landforms - Nitrogen - Reforestation - Restoration - Sediments - Vegetation
Uncontrolled terms:China's loess plateaux - Grain for green projects - Habitat restoration - Linear correlation - Loess Plateau - Natural restoration - Temporal variation - Vegetation restoration
Classification code:402 Buildings and Towers - 409 Civil Engineering, General - 444 Water Resources - 481.1 Geology - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry
DOI:10.3969/j.issn.1002-6819.2014.23.019
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 39>
Accession number:20150400457714
Title:Development and application of intelligent monitoring and controlling system of cotton-picking machine based on virtual instrument technology
Authors:Miao, Zhonghua (1); Lu, Mingchao (1); Hu, Xiaodong (1); Zou, Zhaoguang (1)
Author affiliation:(1) Mechatronics Engineering and Automation, Shanghai University, Shanghai, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:35-42
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to solve the key problems generated in the development procedure of virtual instrument, this paper used controller area network (CAN) bus and LabVIEW touch panel module to develop virtual instrument based on ARM11 and WinCE. Because of the difference between PC and ARM platform, there are big problems in high-speed CAN data transmission and cross-platform call of dynamic link library (DLL). This paper mainly studied CAN bus communication mechanism and its implementation method, and developed the driver program and DLL in embedded WinCE system. And this paper made it possible to use LabVIEW virtual instrument technology in embedded WinCE platform based on CAN bus communication. LabVEIW graphical design environment not only accelerated the development process but also made it easy to make use of the real-time embedded operating system. There are hundreds of advanced signal analysis modules of LabVIEW, mathematical processing modules and rich human-machine interaction modules in LabVIEW touch panel module which insures the fast and friendly interface design and the powerful signal processing and computing process. This paper thoroughly introduced the implementation method of virtual instrument technology in embedded WinCE system and explained the call flow of cross-platform dynamic link library. To achieve the communication between embedded virtual instrument and CAN bus, this paper firstly developed the bottom driver program and the DLL suitable for Win32 platform and the DLL suitable for embedded platform. And then through the shared library block in LabVIEW, this paper achieved the advanced application of the DLL. At last, this paper finished the virtual instrument development based on the touch panel module in LabVIEW. The interface was well designed which looked very simple but practical. This paper has mastered the key technology of seamless link of CAN data. It took the six-row auto-pack cotton-picking machine as the object to develop an intelligent monitoring and controlling system based on CAN bus and embedded WinCE system. The field test was done in NongYiShi crop construction area of Alar, Aksu, Xinjiang The system achieved online monitoring and error alarming to the work state of cotton harvester. Apart from that, three functional verifications were also done. 1) Central controller can transmit collected data from data acquisition module and state monitoring module to the virtual instrument. 2) Through the touchable embedded virtual instrument interface, people can configure any node in CAN network. The configuration includes parameter setting, task allocation and so on. 3) This system can effectively detect the sensor fault and actuator failure and send the diagnosis messages to the customers. From the data provided by the field test we can see the advantage and promising future of virtual instrument based on embedded system. The system effectively realizes the high-speed CAN bus data communication among multiple CAN nodes, and the system has also strong flexibility and versatility, which can be taken as reference and guide in improving the automation and information level of large equipment in China. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Monitoring
Controlled terms:Computer programming languages - Computer software - Control equipment - Control system synthesis - Controllers - Cotton - Data acquisition - Data communication equipment - Data communication systems - Design - Digital instruments - Digital libraries - Embedded systems - Process control - Signal processing - Software design
Uncontrolled terms:Controller-area-network bus - Cotton pickers - Embedded WinCE - Intelligent monitoring systems - LabViEW
Classification code:408 Structural Design - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 723 Computer Software, Data Handling and Applications - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 732.1 Control Equipment - 819.1 Natural Fibers - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.23.005
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 40>
Accession number:20150400457733
Title:Biomechanical characteristics of root systems of Hedysarum scoparium and Salix psammophila
Authors:Tian, Jia (1); Cao, Bing (1); Ji, Jinnan (2); Li, Caihua (1); Zhu, Li (1); Ma, Niyuan (1)
Author affiliation:(1) College of Agriculture, Ningxia University, Yinchuan, China; (2) Key Lab of Soil and Water Conservation and Desertification Combating, Ministry of Education, Beijing Forestry University, Beijing, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:192-198
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hedysarum scoparium and Salix psammophila play an important role to contribute to sandy soil conservation in Mu Us Desert. In order to reveal the biomechanical properties of these two common shrub species, 5-years-old plant specimens were collected in the Gaoshawo forest field (northwest China) by in situ excavation. The root biomechanical characteristics of Hedysarum scoparium and Salix psammophila were measured by laboratory tensile tests and in situ uprooting tests. To analyze data from those experiments, we used regression and ANCOVA (analysis of covariance) to determine the relationship between roots biomechanical characteristics and root diameter or basal diameter. Results showed that a significant power and linear relationship existed between biomechanical characteristics and root diameter or basal diameter in the two species. The root maximum tension increased with root diameter but tensile strength and Young's modulus increased with decreasing root diameter according to a power function. The maximum uprooting force increased linearly with basal root diameter. The root maximum tension of Hedysarum scoparium was (0.16±0.01) kN (diameter from 0.91-6.46 mm) and Salix psammophila was (0.23±0.01) kN (diameter from 0.78-7.44 mm). The tensile strength of Hedysarum scoparium was (25.38±0.90) MPa and Salix psammophila was (36.68±1.18) MPa. Young's modulus of Hedysarum scoparium was (0.10±0.01) GPa and Salix psammophila was (0.19±0.01) GPa. The tensile strength of two species can reach 6.86% and 9.91% of the first grade steel (370 MPa). It showed that roots had obvious reinforcement function. Roots specimens for each species were tested for the maximum uprooting force measurement. The results showed that the maximum uprooting force of Hedysarum scoparium was (1.71±0.16) kN (basal diameter from 17.65-42.68 mm) and Salix psammophila was (1.18±0.16) kN (basal diameter from 20.35-48.07 mm). Results of ANCOVA using root diameter or basal diameter as a covariate showed that there was significant difference in the root maximum tension (P<0.001), tensile strength (P<0.001), Young's modulus (P<0.001) and roots maximum uprooting force (P<0.05) between two species. Compared to two species, Salix psammophila roots had better biomechanical characteristics in aspect of root maximum tension, tensile strength and Young's modulus. But results of root maximum uprooting force showed that Hedysarum scoparium roots had a better comprehensive biomechanical characteristics than Salix psammophil and hence an better root reinforcement. The maximum uprooting force of Hedysarum scoparium roots was 44. 92% higher (0.53 kN) than that of Salix psammophila in the same basal diameter. However, the biomechanical characteristics of single root can not be used as the judgment for root reinforcement ability of the whole tree. The results of this research can serve as a basis for the further studies on biomechanical characteristics of roots and root reinforcement. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Tensile strength
Controlled terms:Biomechanics - Elastic moduli - Pulp manufacture - Regression analysis - Reinforcement - Soil conservation - Soil testing - Soils - Tensile testing
Uncontrolled terms:Analysis of covariances - Biomechanical characteristics - Biomechanical properties - Hedysarum scoparium - Linear relationships - Root reinforcement - Salix psammophila - Uprooting force
Classification code: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 - 483.1 Soils and Soil Mechanics - 811.1.1 Papermaking Processes - 922.2 Mathematical Statistics - 931.1 Mechanics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.23.024
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 41>
Accession number:20150400457710
Title:Development and experiment of 4LT-A staggered-dig sugar beer combine
Authors:Gu, Fengwei (1); Hu, Zhichao (1); Wu, Huichang (1); Peng, Baoliang (1); Gao, Xuemei (1); Wang, Shenying (1)
Author affiliation:(1) Nanjing Research Institute of Agricultural Mechanization, Ministry of Agriculture, Nanjing, China
Corresponding author:Hu, Zhichao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Sugar beet was the most important source of sugar in the sugar industry, with the sugar amounting to about 17% of China's total sugar production. As a seasonal operation, sugar beet harvesting in China was still mainly manual work, having the problems of high labor intensity, low efficiency, great harvest losses and huge occupation of farming and so on, which constrained the further development of the sugar beet industry. Mechanized harvesting was the inevitable development trend of sugar beet harvest. Beet harvest mechanization development had lagged in our country for a long time. And we were lack of a thorough system research about sugar beet harvest mechanization technology, especially the advanced combine technology. The current domestic sugar beet harvesters were basically simple sectional operating machinery. Sugar beet combine harvesters were mainly imported from abroad, having high automation and intelligence degree and advanced performance. But imported machines had the problems of poor adaptability and high prices. The domestic beet combines were still in the prototype development stage, having a great gap with the advanced foreign technology. In order to improve the mechanization level and reduce the costs of sugar beet harvest machine, a staggered-dig sugar beet combine was developed, fully digesting and absorbing advanced technology, combined with the sugar beet grain planting scale, economic conditions, and the present situation of domestic machinery manufacturing level. The overall structure includes traction frame, row detection mechanism, round coulter, copying cut top institution, digging and conveying institution, side of threshing mechanism, walking system, cage type rotary lifting device, conveying equipment, main frame, stock bin, top conveyer and so on. The sugar beet combine adopted the key technologies such as top contour cutting, auto-follow row system, hydraulic technology, sensor signal acquisition technology and microprocessor control technology. While working, the combine harvester was dragged forward by tractor, copying cut top institution and sides of threshing mechanism finished cut the top and hit the leaf. Row detection mechanism detects the position of the ridge top beetroot block, converts the offsets of excavation forward locus to angle quantity, and then sends to the offset angle acquisition sensor. The offset angle acquisition sensor converts angle information to digital signal, and sends it to the controller. Controller handles angle signal and outputs a control signal for the solenoid valve, through the control software analysis, open hydraulic cylinder drive oil line. The hydraulic cylinder drives the traction biasing mechanism, adjusting the digging position. The adjacent inter-row twining stem and leaf were cut off by round coulter in time, guaranteeing the smoothness of mining harvest. Digging and conveying institution dug the beet root out, and then were delivered into the stock bin by cage type rotary lifting device. The results of Experiments showed that the harvester operating smoothly and reliably, the root impurity rate was less than 2%, the root fracture rate was less than 3.5%, the loss rate of beet root was less than 4%, and the toppers pass rate was greater than 85%. All indicators had reached the national standard, in line with the requirements of beet harvest. The study of auto-follow row technology, top contour cutting technology, and low damage mining technology can provide effective reference for the independent research and development of sugar beet harvesting machinery. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Sugar industry
Controlled terms:Agriculture - Bins - Combines - Controllers - Conveying - Cylinders (shapes) - Harvesters - Harvesting - Hydraulic machinery - Machinery - Mechanical actuators - Mechanization - Mergers and acquisitions - Signal detection - Signal processing - Solenoid valves - Sugar beets - Technology transfer
Uncontrolled terms:Development - Independent research - Machinery manufacturing - Mechanized harvesting - Microprocessor control - Operating machineries - Prototype development - Sugar beet harvesters
Classification code:408.2 Structural Members and Shapes - 505.3 Nonmetallic Mining Equipment - 601 Mechanical Design - 619 Pipes, Tanks and Accessories; Plant Engineering Generally - 632.2 Hydraulic Equipment and Machinery - 694.4 Storage - 716.1 Information Theory and Signal Processing - 732.1 Control Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822 Food Technology - 911.2 Industrial Economics - 912 Industrial Engineering and Management
DOI:10.3969/j.issn.1002-6819.2014.23.001
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.
<RECORD 42>
Accession number:20150400457740
Title:Evaluation on aeration performance of movable solar aerator
Authors:Wu, Zongfan (1); Cheng, Guofeng (1); Wang, Xianrui (1); Liu, Xingguo (1); Zhang, Yongjun (1); Zou, Haisheng (1); Tang, Rong (1)
Author affiliation:(1) Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai, China; (2) Key Laboratory of Fishery Equipment and Engineering, Ministry of Agriculture, Shanghai, China
Corresponding author:Liu, Xingguo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:23
Issue date:December 1, 2014
Publication year:2014
Pages:246-252
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In pond aquaculture, it is usually necessary in sunny noon that running aerator stirs pond water, so that the supersaturated dissolved oxygen (DO) from phytoplankton's photosynthesis in upper water can be transferred into the relatively anoxic bottom, reducing the "oxygen debt" of bottom water and preventing fish hypoxia at the next early morning. However, this approach consumes a lot of electric energy and has low efficiency. To improve the ecological state of aquaculture ponds and save electric energy, a movable solar aerator was designed and developed. This machine is solar-powered and can move upon the water, and mainly consists of a photovoltaic power system, a water walking device, and a wave aerator. The photovoltaic power system provides power for the entire machine, while the water walking device drives the whole equipment, moving back and forth along a steel rope. The wave aerator can rotate itself and around the main part of the equipment (the photovoltaic power system and water walking device), affecting large areas of the pond. The rotation of the wave aerator makes the formation of water waves and promotes pond water convection between the surface and the bottom. The purpose of this study was to evaluate the performance of the movable solar aerator on mechanical aeration and water exchange between the surface and the bottom, and also on its practical effect in ponds, by 3 tests of aeration efficiency, water pumping capacity, and aeration effect in ponds, respectively. For standardizing the test, a battery providing the same voltage (24 V) was used instead of the photovoltaic power system in the tests of mechanical aeration efficiency and water pumping capacity. The values of performance obtained from this method of using a battery are the maximum values for the equipment. The obtained results showed that the machine increased the DO in the water of a pool (54.8 m<sup>3</sup>) from 0.84 to 7.88 mg/L within 36 minutes. The maximum mechanical aeration capacity was 1.24 kg/h, with a power efficiency of 2.59 kg/(kW·h), maximum pumping water capacity of 1 254.4 m<sup>3</sup>/h, and pumping dynamic efficiency of 2613.3 m<sup>3</sup>/(kW·h). The test of practical application effect in ponds was conducted from 07: 00 a. m. on September 12, 2013 to 05: 00 a. m. on September 13, 2013 at the pond ecological engineering research center of Chinese academy of fishery sciences (Shanghai), with the maximum sunlight intensity of 57 200 lx. The pond selected was 70 m in length and 25 m in width, with a depth of 1.6 m. The aerator ran automatically from 07: 00 to 16: 00, with a total running time of 9 hours. The DO concentrations of 0.2, 0.5, 1.0 and 1.5 m pond water were recorded with an interval of 2 hours. The results showed that the DO values of the bottom water (1.5 m) in control were maintained at 3.1-3.8 mg/L, whereas the values in the test pond were substantially increased with the maximum of 7.8 mg/L, due to the good performance of the movable solar aerator on mechanical aeration and water exchange. The DO uniformity of the test pond was maintained at 72%-84%. The DO environment in the bottom pond was improved greatly. These results revealed that the movable solar aerator has good performance on mechanical aeration and water exchange, thus, effectively improving the DO level in the bottom water of ponds and increasing DO uniformity. The present study provides a data basis for further popularization and application of the movable solar aerator developed newly. ©, 2014, Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Water aeration
Controlled terms:Aquaculture - Biochemical oxygen demand - Digital storage - Dissolved oxygen - Ecology - Electric batteries - Environmental management - Equipment - Fish ponds - Lakes - Oxygen - Photovoltaic cells - Ponding - Ponds - Solar energy - Solar power generation - Water waves
Uncontrolled terms:Aeration efficiencies - Application effect - Dynamic efficiency - Ecological engineering - Photovoltaic power systems - Sunlight intensity - Walking devices - Wave aerators
Classification code:402 Buildings and Towers - 407 Maritime and Port Structures; Rivers and Other Waterways - 445.1 Water Treatment Techniques - 453 Water Pollution - 454 Environmental Engineering - 471.4 Seawater, Tides and Waves - 615.2 Solar Power - 702.1 Electric Batteries - 702.3 Solar Cells - 722.1 Data Storage, Equipment and Techniques - 741.3 Optical Devices and Systems - 804 Chemical Products Generally - 821.3 Agricultural Methods - 901 Engineering Profession
DOI:10.3969/j.issn.1002-6819.2014.23.031
Database:Compendex
Compilation and indexing terms, Copyright 2015 Elsevier Inc.