<RECORD 1>

Accession number:20163302706396
Title:Structural shrinkage characteristics and modified moisture diffusion kinetics model of sliced eggplant dried by hot air
Authors:Chen, Liangyuan (1); Han, Lifeng (1); Li, Xu (1); Xu, Bingyang (2); Qian, Yumei (3); Zhu, Wenkui (1) 
Author affiliation:(1) Zhengzhou Tobacco Research Institution of CNTC, Zhengzhou; 450001, China; (2) China Tobacco Jiangxi Industrial Co., Ltd., Nanchang; 330096, China; (3) College of Food Science and Engineering, Zhengzhou University of Light Industry, Zhengzhou; 450001, China 
Corresponding author:Zhu, Wenkui(wkzhu79@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:275-281
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hot air drying is commonly used to dehydrate fruit and vegetable slices in the agricultural product processing industries. So it is important to establish a kinetic model of the drying process that can accurately describe heat and mass transfer for optimizing processes, improving drying quality and saving drying energy. However, fruits and vegetables as porous media, always have a significant volume shrinkage during drying, and many previous studies of porous media ignored the characteristics of macro-volume shrinkage with drying or more directly simplified the porous media as the materials just with a rigid skeleton, which was contributed to the situation in which there was no further analysis about the effects of the shrinkage on drying processing. Furthermore, eggplant, one of the main vegetable varieties in China, due to its short shelf life, was often sliced and dehydrated to preserve its equality instead of being eaten freshly, and the texture of eggplant is soft and porous, so its dry tissue is easy to shrink and deform during the whole hot air drying. Hence, in this paper, eggplant was chosen as the experimental porous material, and the testing methods, such as the density analysis, scanning electron microscope (SEM) analysis and mercury intrusion testing, were used to analyze the variation of sliced eggplant pore volume, structure and volume shrinkage during hot air drying. At the same time, a moisture diffusion kinetic model based on the shrinkage characteristics of the slices was established to study the effect of shrinkage on drying kinetics of sliced eggplant. As a result, internal pore volumes of the eggplant approximately linearly decreased with its moisture rate decreasing, but they were not obviously changed with hot air temperatures. During the drying processing, the proportion of the pores of smaller than 10⁵nm gradually increased, however, the pores of bigger than 10⁵nm that were dominant in the early stage of the drying gradually disappeared due to porous shrinkage caused by moisture loss when drying. In addition, according to the results of mercury intrusion testing, the peak of pore size decreased from 1.5&times;10⁵to 4&times;10⁴nm. In consideration of shrinkage properties of porous media, this work explored the influence of drying temperature on internal structure of sliced eggplant and modified the drying kinetic models based on the Fick's second diffusion law. Among those volume shrinkage models, Hatamipour model and Quadratic model could describe the real volume shrinkage better. After modifying the drying model based on Fick's second law with Quadratic shrinkage model that was selected as the best empirical shrinkage model due to its simplicity and accuracy, the convective drying kinetic model of eggplant slices could fit the experimental results more accurately. Moreover, apparent activation energy (AAE) of the sliced eggplant increased from 20.69 to 25.76 kJ/mol, indicating that the shrinkage of eggplant increased the mass transfer resistance during the process, which proved that the effective diffusion coefficient of water was overestimated obviously when not considering the influence of shrinkage on dynamics during the drying. In short, the modified kinetics models can provide a more objective evaluation of the drying characteristics of the deformable porous material and the reference for the optimization of its drying process. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Drying
Controlled terms:Activation energy - Agricultural products - Diffusion - Enzyme kinetics - Food technology - Fruits - Kinetic parameters - Kinetic theory - Kinetics - Mass transfer  - Mercury (metal) - Moisture - Pore size - Porous materials - Scanning electron microscopy - Shrinkage - Solar dryers - Thermal processing (foods) - Vegetables
Uncontrolled terms:Apparent activation energy - Deformable porous materials - Drying characteristics - Effective diffusion coefficients - Heat and mass transfer - Mass transfer resistances - Shrinkage characteristic - Sliced eggplant
Classification code:549.3  Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 641.3  Mass Transfer - 657.1  Solar Energy and Phenomena - 821.4  Agricultural Products - 822  Food Technology - 822.2  Food Processing Operations - 931  Classical Physics; Quantum Theory; Relativity - 951  Materials Science
DOI:10.11975/j.issn.1002-6819.2016.15.038

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 2>

Accession number:20163302706370
Title:Simulation and experiment on flow field characteristics of concentrated device of concentrated wind energy turbines in wind shear
Authors:Tian, De (1); Ma, Guangxing (2); Lin, Junjie (1) 
Author affiliation:(1) State Key Laboratory for Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing; 102206, China; (2) Civil Engineering Institute, Inner Mongolia University of Technology, Huhhot; 010051, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:83-88
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The influence of wind shear cannot be ignored in large wind turbine systems, such as CWETS (concentrated wind energy turbine generator systems) that can increase the density and stability of wind energy. Concentrated wind energy device is the core component of concentrated wind energy turbine. To reveal wind shear flow laws inside the concentrated wind energy device, the numerical calculation of wind shear characteristics and the wind tunnel experiments of the flow field were performed with the concentrated wind energy device as the research object. Based on the geometry model and mesh model built by the three-dimensional modeling software and CFD (computational fluid dynamics) software, the wind flow was simulated in a specific wind field. The fluid medium was the air and the velocity-inlet and pressure-outlet were adopted. The inlet velocity was set as 12.075h^0.2385and the gauge pressure of the outlet was set to 0 Pa. Other boundaries were set as stationary wall and no slip. The physical model was simplified to the steady incompressible fluid problem without heat transfer, and basic governing equations were continuity equations and Navier-stokes equations. The turbulence model was standard k-&Epsilon; model. Simulation results showed that the concentrated wind energy device had the ability of enhancing the wind power quality and load uniformity in wind shear. To verify the credibility of numerical calculation results, the wind tunnel experiment was conducted in the movable field OFDY-12 wind tunnel developed by Inner Mongolia Agricultural University, and the experimenting prototype had the same scale with the numerical calculation model. Flow field calibration of the wind tunnel was performed, firstly, and the suitable flow field was selected, where the wind velocity gradient was 4.2 s^-1. Wind velocity gradient was calculated based on the measured velocities of the highest point and the lowest point in the wind tunnel. Then the concentrated wind energy device was fixed at the selected location inside the wind tunnel, and the center line was 595 mm higher than the bottom of the wind tunnel and located in the middle section of the wind tunnel. The total pressure and static pressure of different test points on axial and radial direction inside the concentrated wind energy device were measured by the Pitot tube and multi- channel pressure gauge. The influence rule of concentrated wind energy device on the wind shear was concluded by analyzing the test data. The temperature recorded in the experiment fluctuated from -1 to -0.5&#8451; and the atmospheric pressure was from 899 to 900 hPa. Numerical calculation results were reasonably verified by wind tunnel experiments. In addition, it was suggested that the method of numerical computation was feasible for the research on the wind shear problems of concentrated wind energy device. And the concentrated wind energy device had its effect on reducing the wind shear with the velocity gradient reducing from 4.2 to 3.4 s^-1. Besides, it was showed that the device in the wind shear had the ability of improving the wind power quality and load uniformity. Numerical computation results were always greater than the experimental data obtained with the model in the same size. However, the general trends were almost the same. The main reason was that the numerical simulation model was too idealized to embody the asymmetric degree and wall thickness of the actual experiment model, which would be solved in the future research. All the results and conclusions can provide a basis for wind shear study and optimization design of the concentrated wind energy device. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Shear flow
Controlled terms:Air - Atmospheric pressure - Computational fluid dynamics - Computational geometry - Concentration (process) - Flow fields - Heat transfer - Navier Stokes equations - Numerical methods - Numerical models  - Power quality - Turbogenerators - Turbulence models - Velocity - Walls (structural partitions) - Wind - Wind effects - Wind power - Wind tunnels - Wind turbines
Uncontrolled terms:CFD (computational fluid dynamics) - Concentrated wind energies - Flow field calibration - Numerical calculation model - Numerical computations - Three-dimensional model - Wind shears - Wind tunnel experiment
Classification code:408.2  Structural Members and Shapes - 443.1  Atmospheric Properties - 615.8  Wind Power (Before 1993, use code 611 ) - 631.1  Fluid Flow, General - 641.2  Heat Transfer - 651.2  Wind Tunnels - 705.2  Electric Generators - 706.1.2  Electric Power Distribution - 723.5  Computer Applications - 804  Chemical Products Generally - 921  Mathematics
Numerical data indexing:Pressure 0.00e+00Pa, Pressure 8.99e+04Pa to 9.00e+04Pa, Size 5.95e-01m
DOI:10.11975/j.issn.1002-6819.2016.15.012

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 3>

Accession number:20163302706379
Title:Composite soil conditioner with carbonized rice husk improving soil environment and increasing yam yield
Authors:Zhang, Shuhui (1, 2); Xie, Guoqiang (3); Han, Xiaori (1); He, Rui (1, 2); Li, Jinke (4); Cheng, Xianguo (2) 
Author affiliation:(1) College of Land and Environment, Shenyang Agricultural University, Shenyang; 110866, China; (2) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China; (3) Jiujiang Academy of Agricultural Sciences, Jiujiang; 332000, China; (4) Ruichang Yam Center, Ruichang; 332200, China 
Corresponding author:Cheng, Xianguo(chengxianguo@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:150-156
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The growth and development of yam (Dioscorea opposite L.) are closely related to the quality of soil. Therefore, improvement of soil quality is a crucial means to increase the quality and yield of yam. In this study, in order to explore the effects of soil conditioner on soil physical-chemical properties and bacterial community, to provide technology support for the improvement of soil environment and scientific management of yam cultivation, a special kind of soil conditioner, which was mainly constituted by carbonized rice husk and a few natural mineral substances, was applied in the plant region of yam in Ruichang of Jiangxi Province. The results showed that: 1) The soil conditioner significantly changed soil physical-chemical properties and there were significant increases in soil pH, organic matter, total nitrogen, available phosphorus, available potassium, soil moisture, geometric mean diameters of aggregates and total porosity, while soil bulk density in the treatment with soil conditioner decreased. 2) The high-throughput sequencing indicated that the treatment with soil conditioner significantly increased the diversity of soil bacterial community. The relative abundance of phyla Acidobacteria revealed a remarkable increase by 12.85%, but the relative abundance of phyla Proteobacteria decreased by 3.90% and the class &gamma; Gammaprotebacteria decreased significantly compared to control treatment. The relative abundance of phyla GAL15, AD-3 and Planctomycetes also decreased by 7.50%, 4.40% and 0.95%, respectively compared to control. The relative abundance of phyla Chloroflexi, Verrucomicrobia, Gemmatimonadetes and Bacteroidetes in the soil with soil conditioner apparently increased by 1.95%, 1.10%, 1.05% and 0.53%, respectively. 3) The soil conditioner not only increased the contents of chlorophyll and proline in the leaves of yam, but also significantly increased the activity of superoxide dismutase in yam tuber tissues. At the same time, the application of soil conditioner facilitated the growth of yam and increased its disease and pest resistant ability. Finally, both the quality and yield were improved by the soil conditioner. This study indicated that the soil conditioner played an important role in the amelioration of soil environment, and increased the resistance ability of yam to the infection of both disease and pest. Therefore, reasonable application of soil conditioner would be an efficient way to improve the quality and yield of yam. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Soil conditioners
Controlled terms:Bacteria - Chemical properties - Enzyme activity - Enzymes - Oxygen - pH - Plants (botany) - Productivity - Soil moisture - Soils
Uncontrolled terms:Bacterial community - Carbonized rice husks - Geometric mean diameters - Growth and development - High-throughput sequencing - Physical chemical property - Physiological characteristics - Soil bacterial community
Classification code:461.9  Biology - 483.1  Soils and Soil Mechanics - 801  Chemistry - 801.1  Chemistry, General - 804  Chemical Products Generally
Numerical data indexing:Percentage 1.05e+00%, Percentage 1.10e+00%, Percentage 1.28e+01%, Percentage 1.95e+00%, Percentage 3.90e+00%, Percentage 4.40e+00%, Percentage 5.30e-01%, Percentage 7.50e+00%, Percentage 9.50e-01%
DOI:10.11975/j.issn.1002-6819.2016.15.021

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 4>

Accession number:20163302706382
Title:Detection method of porcelain insulator contamination grade based on infrared-thermal-image
Authors:Fang, Junlong (1); Wang, Jinxia (1); Yang, Liu (1); Wang, Guannan (1); Han, Jianing (1); Guo, Shichang (1) 
Author affiliation:(1) College of Electric and Information, Northeast Agricultural University, Harbin; 150030, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:175-181
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the popularization of high or extra-high voltage power transmission and the continuous improvement of grade of wire and voltage, some power grids frequently have pollution flashover accidents. Therefore, it is very important to effectively and accurately obtain the insulator contamination grade for the safe operation of power grid. Currently, major detecting methods of insulator contamination grades include equivalent salt deposit density method, leakage current method, frequency spectrum method, and so on. Although above mentioned methods are feasible, basically, all of them mainly focus on the treatment of single insulator without paying attention to the entire group of insulators' heating features and appearance characteristics of the heating zone. Therefore, according to the heating features of polluted insulators, a new detecting method of porcelain insulator contamination grade, which was based on color image treatment, was proposed under the purpose of simplifying the procedures as well as reducing the misdetection ratio of the present detecting method. It meant that the assessment of samples' contamination grades would be performed under a color-image-based treatment on the obtained insulator infrared thermogram. Firstly, the infrared thermograms, which were taken at the scene, were denoised by two-step method (Gaussian noise was denoised by the wavelet adaptive diffusion after the impulse noise was denoised by the median filtering method) to obtain the filtered insulator thermogram. Secondly, they were segmented based on the differences of the component R, G, and B respectively shown by the normal insulators, the broken insulators, and the corresponding infrared thermograms. Although the traditional OTSU segmentation algorithm is simple and effective, it is not suitable to apply on the image segmentation without clear bimodal histogram. Therefore, the presented paper completed the image threshold segmentation by combining the characteristics of wavelet transform and OTSU. The modified OTSU was adaptive to choose the optimal threshold value, and improved the obtained image quality after the segmentation. However, the binary images obtained from the segmentation still had lots of noise points and cavities. Therefore, the mathematical morphology of the obtained binary image was modified twice in order to obtain a polluted area of the insulator. Thirdly, 5 feature components, including ratio of area to perimeter, average value, extreme value, standard deviation as well as major-minor axis ratio of the smallest outer ellipse, were extracted from the R channel of the polluted area by taking advantage of a statistical method, and the back propagation (BP) neural network was trained. During the training, the transfer function of the hidden layers was the logarithmic transfer function, logsig. The neural transfer function of the output layers was the linear activation function, purelin, which regarded image characteristic values as the input of the network, and the salt deposit density as the output that would be transformed to the corresponding contamination grade. Consequently, a detecting model of contamination grades was constructed on the basis of the color image. Finally, the running conditions of the insulators in the Qitaihe Power Supply Company were tested, among which the relative humidity, one of the shooting conditions, was at 78%-91% in the experiment. However, the temperature of the experiment was adjusted as 10-30&#8451; because the infrared thermogram was hardly affected by the shooting temperature. The contamination grade of each insulator was recorded according to the regulations of GB/T 5582-4993 when each infrared thermogram was shot. A total of 500 groups of infrared thermograms were obtained from XP-70 porcelain insulator with 0, I, II, III and IV polluted grade respectively, which were selected as experimental samples. This system was tested repeatedly, and the overall detecting precision reached above 91%. The experimental result shows that the insulator contamination grades are more accurate when the appearance characteristics of polluted insulators and the features of infrared thermogram are combined during the detection. It can also be noted that such a method can be served as the foundation of the detection of insulator contamination grades in the complicated outdoor environment. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Image segmentation
Controlled terms:Algorithms - Backpropagation - Binary images - Color - Contamination - Deposits - EHV power transmission - Electric insulators - Electric power transmission networks - Feature extraction  - Gaussian noise (electronic) - Impulse noise - Infrared imaging - Mathematical morphology - Median filters - Neural networks - Pollution detection - Porcelain - Salt deposits - Temperature measuring instruments  - Thermography (temperature measurement) - Transfer functions - Wavelet transforms
Uncontrolled terms:Back propagation neural networks - Continuous improvements - Equivalent salt deposit density - Insulator - Insulator contamination - Linear activation function - Neural transfer functions - Segmentation algorithms
Classification code:505.1  Nonmetallic Mines - 703.2  Electric Filters - 706.1.1  Electric Power Transmission - 723.2  Data Processing and Image Processing - 723.4  Artificial Intelligence - 741.1  Light/Optics - 746  Imaging Techniques - 812.1  Ceramics - 921  Mathematics - 921.3  Mathematical Transformations - 944.5  Temperature Measuring Instruments - 944.6  Temperature Measurements
Numerical data indexing:Percentage 7.80e+01% to 9.10e+01%, Percentage 9.10e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.024

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 5>

Accession number:20163302706387
Title:Effects of different types of carbon based filter materials on purification of livestock wastewater by earthworm bioengineering bed
Authors:Zhao, Haitao (1); Li, Zongyu (1); Yan, Zhijun (2); Zhang, Mingyue (2); Li, Tianpeng (1); Zheng, Shengyang (1) 
Author affiliation:(1) College of Environmental Science and Engineering, Yangzhou University, Yangzhou; 225127, China; (2) Nanjing Hydraulic Research Institute, Ministry of Water Resources, Nanjing; 210029, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:213-218
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Earthworm is a soil residence animal, which can effectively enrich and remove nutrients in the environment, and its role in the field of ecological environment has gained more and more attention. Earthworm bioengineering bed can efficiently purify various sewages. In such bioengineering, the filter is an important part, and carbon material is the core material of the filler. In order to determine the impact of the carbon types on the earthworm bioengineering bed, in this study, rice straw and biochar were used as carbon source filler, and livestock wastewater was added to the bioengineering bed at different time interval. The inlet and outlet water quality parameters were continuously monitored for 22 d. Results showed that bioengineering bed of rice straw as filler could significantly reduce various pollutants in livestock wastewater. The pollutant reduction was 67.2% of nitrate nitrogen, 81.4% of ammonium nitrogen, 79.5% of total nitrogen, 29.9% of phosphate, 35.2% of total phosphorus, 21.4% of COD (chemical oxygen demand) and 77.8% of EC (electric conductivity) value. The bioengineering bed of rice straw filler changed the pollutant reduction in the addition of earthworms. The increase of average reduction was 11.1% of ammonium nitrogen, 10.4% of total nitrogen, 17.8% of phosphate, 73.9% of total phosphorus and 27.3% of COD, and the average reduction was 10.3% of nitrate nitrogen and 3.4% of EC value. Bioengineering bed of biochar as filler could significantly reduce various pollutants in livestock wastewater, and pollutant reduction was 36.8 % of nitrate nitrogen, 86.2% of ammonium nitrogen, 53.4% of total nitrogen, 21.2% of phosphate, 33.3% of total phosphorus, 33.3% of COD and 51.7% of EC value. The bioengineering bed of biochar filler increased the pollutant reduction in the addition of earthworms, and the increase of average reduction was 0.4% of nitrate nitrogen, 1.4% of ammonium nitrogen, 10.6% of total nitrogen, 26.0% of phosphate, 29.5% of total phosphorus, 39.2% of COD and 0.7% of EC value. After bioengineering bed treatment, average increase of pH value of outlet water was 3.1% for rice straw as filler, and 7.7% for biochar as filler. The average decline rate of pH value of the outlet water in adding earthworms was 0.1% and 7.7%. In summary, the type of carbon and earthworm activity significantly influenced the effect of livestock wastewater purification for the earthworm bioengineering bed. The straw filler was beneficial to the reduction of nitrate nitrogen, total nitrogen, phosphate, total phosphorus and EC of the livestock wastewater. Biochar filler was conducive to the reduction of ammonium nitrogen and COD in livestock wastewater, and significantly increased the pH of outlet water. The removal rate of ammonium nitrogen, total nitrogen, phosphate, total phosphorus and COD was significantly improved after adding earthworm into bioengineering bed, but it was not conducive to the removal of nitrate nitrogen. It was the most conducive to the removal of pollutants in livestock wastewater that adding earthworm into the bioengineering bed filler which was made by the biochar and straw in a certain proportion. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Nitrogen removal
Controlled terms:Agriculture - Bandpass filters - Chemical oxygen demand - Coremaking - Fillers - Nitrates - Nitrogen - pH - Phosphorus - Pollution  - Purification - Sewage - Straw - Wastewater - Water pollution - Water quality
Uncontrolled terms:Ammonium nitrogen - Bio chars - Earthworm activities - Earthworm bioengineering bed - Ecological environments - Livestock - Livestock wastewater - Total phosphorus
Classification code:445.2  Water Analysis - 452.1  Sewage - 452.3  Industrial Wastes - 453  Water Pollution - 534.2  Foundry Practice - 703.2  Electric Filters - 801.1  Chemistry, General - 804  Chemical Products Generally - 804.2  Inorganic Compounds - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5  Agricultural Wastes
Numerical data indexing:Percentage 1.00e-01%, Percentage 1.03e+01%, Percentage 1.04e+01%, Percentage 1.06e+01%, Percentage 1.11e+01%, Percentage 1.40e+00%, Percentage 1.78e+01%, Percentage 2.12e+01%, Percentage 2.14e+01%, Percentage 2.60e+01%, Percentage 2.73e+01%, Percentage 2.95e+01%, Percentage 2.99e+01%, Percentage 3.10e+00%, Percentage 3.33e+01%, Percentage 3.68e+01%, Percentage 3.92e+01%, Percentage 4.00e-01%, Percentage 5.17e+01%, Percentage 5.34e+01%, Percentage 3.40e+00%, Percentage 3.52e+01%, Percentage 7.70e+00%, Percentage 6.72e+01%, Percentage 7.00e-01%, Percentage 7.39e+01%, Percentage 7.78e+01%, Percentage 7.95e+01%, Percentage 8.14e+01%, Percentage 8.62e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.029

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 6>

Accession number:20163302706371
Title:Simulation and validation of additional virtual damping control of permanent magnet synchronous wind power system
Authors:Liu, Jun (1); Zhou, Feihang (1); Huang, Yang (1) 
Author affiliation:(1) College of Automation, Xi'an University of Technology, Xi'an; 710048, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:89-96
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Torsional vibration of permanent magnet synchronous generator (PMSG) shafting not only will increase the fatigue damage of the shafting, but also can seriously affect the stability and reduce the service lifetime of wind turbine generator (WTG). Torsional vibration problem of large WTG becomes increasingly prominent. In order to ensure high efficient and stable operation of the WTG, and restrain shafting torsional vibration effectively, this paper expounds the basic control strategy of permanent magnet synchronous wind power system (PMSWPS) in detail, and discusses and analyzes the influence of control parameters and shafting system damping on the system stability and the shafting torsional vibration. It is found that the instability of the shafting torsional vibration will be caused when inappropriately selecting the control parameter, and that the shafting system damping can suppress the torsional vibration, and improve system stability margin. Because of the stronger nonlinearity and complexity of direct-drive PMSWPS (D-DPMSWPS), there exists certain blindness in the setting of control parameters. This paper effectively restrained the shafting torsional vibration caused by the inappropriate parameter selection. The article puts forward a kind of additional virtual damping control method, that is, under the real condition of insufficient shafting damping, introducing the corresponding compensation current at q axis current control loop, which is equivalent to the introduction of damping torque compensation and increasing the shafting system damping. The proposed control strategy has a certain practical significance and practical value for inhibiting the shafting torsional vibration, and improving the stability and WTG service lifetime of the nonlinear complex system D-DPMSWPS, has the same control effect with the actual increase of shafting damping, and can reduce the requirement for the control parameters. We can get the following conclusions by simulation: 1) It can lead to instable torsional vibration, when the control parameter selection is inappropriate. The article chooses 2 groups of control parameters to confirm this conclusion. The first group of control parameters are k<inf>p</inf>=0.0005, k<inf>i</inf>=0.001 and T=0.1 and the second group of control parameters are k<inf>p</inf>=0.0005, k<inf>i</inf>=0.01 and T=0.1. It is found that the instable torsional vibration occurs under the first group of control parameters, but does not occur under the second group of control parameters. 2) Different control parameters have different requirements on shaft system damping. For example, it only needs to increase the shaft system damping to 300 to maintain system stable under the first group of control parameters, while it need not increase the shaft system damping under the second group of control parameters. 3) It can inhibit torsional vibration damping and enhance the stability margin by increasing the shafting. This phenomenon will be found that the instable torsional vibration due to unsuitable control parameter selection can be suppressed effectively by increasing damping of shafting, and the stability margin is enhanced under the first group of control parameters. 4) Additional virtual damping control has the same effect with the actual increase of shaft damping and can suppress torsional vibration. The last conclusion can be validated by computer simulation that it can enhance WTG damping and restrain shafting torsional vibration effectively through introducing additional virtual damping under the real condition of insufficient shafting damping. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Control system stability
Controlled terms:Damping - Elastic waves - Electric generators - Electric power system control - Fatigue damage - Machine vibrations - Magnets - Permanent magnets - Synchronous generators - System stability  - Turbogenerators - Vibration analysis - Vibrations (mechanical) - Wind power - Wind turbines
Uncontrolled terms:Control parameters - Generator - Permanent magnet synchronous generator - Stability margins - Torsional vibration
Classification code:601.3  Mechanisms - 615.8  Wind Power (Before 1993, use code 611 ) - 704.1  Electric Components - 705.2  Electric Generators - 705.2.1  AC Generators - 731.2  Control System Applications - 731.4  System Stability - 931.1  Mechanics - 951  Materials Science - 961  Systems Science
DOI:10.11975/j.issn.1002-6819.2016.15.013

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 7>

Accession number:20163302706381
Title:Weed recognition using SVM model with fusion height and monocular image features
Authors:Wang, Can (1); Li, Zhiwei (1) 
Author affiliation:(1) College of Engineering, Shanxi Agricultural University, Taigu; 030801, China 
Corresponding author:Li, Zhiwei(lizhiweitong@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:165-174
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The technology of weed recognition based on machine vision becomes the research focus of precision agriculture. In order to realize the precise weeding technology, it is required to recognize weeds and crops rapidly and precisely. In this research, the high accurate recognition method of weed was studied. Maize seedlings of 2 to 5 leaves stage and weed during same stage were used as research object and method of accurate recognition of weed based on SVM recognition model that fusion height feature and image features was studied. We found that maize seedlings were generally higher than the weeds during the same period. This fact could allow us to have a more accurate recognition evidence for the SVM recognition model. In this paper, we conducted accuracy analysis. Binocular vision system was built and calibrated, an image acquisition system was designed and binocular images of crops and weeds were grabbed. The calibration results of binocular camera were evaluated using re-projection error. The average re-projection error was 0.08 pixels, and no more than 0.1 pixels. This demonstrated that the binocular image acquisition system had a high accuracy of the calibration processing. We also pretreated the collected images with methods of Excess-green feature, Improved Otsu, Area filtering, Canny edge detection. Sixteen morphological features and two texture features in monocular image based on image pretreatment were obtained. Then we proposed the height feature extraction method of plant. Based on binocular images, the height feature of plant can be extracted by this method quickly. Firstly, with height feature extraction method, the binocular gray image was masked with binocular binary image. With this processing on binocular image, the background information irrelevant to the recognition target was removed and the processing speed of the algorithm was improved. Then the speed up robust feature algorithm was used to detect the feature points in the masked binocular gray image. The method had good robustness. Matching feature points were detected between left and right images by the sum of absolute differences method. Those matching feature points that were not suitable for constraint of epipolar line were removed. Projective transformation matrix was worked out using basic matrix and coordinate of matching feature points. Moreover, the binocular images were corrected based on projective transformation matrix. With these processing, the left image and right image were corrected to the same horizontal epipolar line, the bad effect of mechanical vibration on image quality was reduced, and the robustness of the method in this paper was significantly improved. Next, the accurate disparity map was obtained by combining global error energy minimization algorithm with the average error threshold filter. Matching block in the size of 5 &times; 5 was selected in this processing. In this condition, processing speed of the method was maximized, and calculation precision was satisfied. Finally, according to the geometrical principle of binocular vision, the depth information was calculated based on the disparity map. The maximum depth information of the target area was referred to the height feature of plant. The error between actual height and calculation was less than &plusmn;12mm. After that, we divided weeding period into three stages and built SVM recognition model with fusion height feature and image features for each stage. Based on the max-min ant system algorithm, we selected the optimal morphological features of each model. As a result, the morphological features were reduced from 16 to 6, feature data was reduced by 62.5%. By using three kinds of algorithms: genetic algorithm, k-fold cross validation, and particle swarm optimization, the two core parameters of each SVM recognition model were optimized, and the optimal parameters were selected by comparing effects of three algorithms. The optimal parameters c and g contained by this way can effectively improve the recognition ability of SVM model, and avoid the over-learning and under-learning state of SVM model. The test set was used to test the recognition rate of SVM model of each stage, and the contrast experiment of the SVM model that did not fusion height feature and image features was carried out. After all those processes the weed recognition system was established. It was necessary to segment the overlapping images of maize and weed. Watershed algorithm based on distance transform was used to solve this problem. Firstly, the segmentation line was determined by using watershed algorithm based on distance transformation. Then the overlapping image was segmented by morphology processing for maintain the original shape. Finally, the binary image after segmentation was adopted to mask the gray image and the segmentation of weeds and crops was realized. This method can effectively segment maize and weeds in the seedling stage. The results of this research showed that the recognition rate of the SVM model based on fusion height feature was 96.67%, 100%, 98.33%, with the average recognition rate of 98.33%. The recognition rate of the SVM model based on no fusion height feature was 93.33%, 91.67%, 95%, with the average recognition rate of 93.33%. The data showed that the SVM recognition model based on fusion height feature was better than the model without fusion height feature, and the average recognition rate was improved by 5%. Therefore, weed recognition method based on fusion height feature and SVM model can effectively improve the recognition rate and achieve high accuracy of weed recognition. The research results in this paper will provide reference for the development of precision weeding. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:41
Main heading:Image processing
Controlled terms:Algorithms - Binary images - Binocular vision - Binoculars - Bins - Calibration - Computer vision - Crops - Edge detection - Errors  - Extraction - Feature extraction - Genetic algorithms - Image acquisition - Image fusion - Image matching - Image segmentation - Linear transformations - Matrix algebra - Optimization  - Particle swarm optimization (PSO) - Pixels - Plants (botany) - Stereo image processing - Support vector machines - Vibrations (mechanical) - Watersheds
Uncontrolled terms:Binocular vision systems - Feature extraction methods - Feature fusion - Image acquisition systems - K fold cross validations - Projective transformation matrix - Sum of absolute differences - Weed recognition
Classification code:444.1  Surface Water - 694.4  Storage - 723  Computer Software, Data Handling and Applications - 723.2  Data Processing and Image Processing - 741.2  Vision - 741.3  Optical Devices and Systems - 802.3  Chemical Operations - 821.4  Agricultural Products - 921  Mathematics - 931.1  Mechanics
Numerical data indexing:Percentage 1.00e+02%, Percentage 5.00e+00%, Percentage 6.25e+01%, Percentage 9.17e+01%, Percentage 9.33e+01%, Percentage 9.50e+01%, Percentage 9.67e+01%, Percentage 9.83e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.023

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 8>

Accession number:20163302706363
Title:Design and experiment of propelling mechanism of ornithopter with low-frequency and big-displacement modular umbrella-like wings
Authors:Gao, Fei (1); L&uuml;, Jiangang (1); Zhang, Zhongzhi (1); Guo, Shaoyan (1) 
Author affiliation:(1) The Seventh Department, Mechanics Engineering College, Shijiazhuang; 050003, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:32-38
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is an effective way to mimic the movement of the flapping wings to enhance the thrust-to-power ratio of the air vehicles. But traditional flapping-wing air vehicles should be working under relatively high frequencies to overcome their gravities. It has been a lasting problem to be solved for the model of flapping-wing air vehicles grows in size. In order to solve this problem, the design and experiment of a new type of propulsion technology is described in this paper, which is inspired by the motion feature of the bird's flapping wing. The principle of the propulsion and movement of the modular umbrella-like wings was first developed, and the mechanism used to implement the movement of the modular wings was subsequently designed according to the principle. A structural model and the assembly relationship of the propulsion mechanism were developed for prototype fabrication. The parameters of the propulsion mechanism were confirmed based on the assembly relationships. Then a test bed was made to test the aerodynamics of the wing and propulsion performance of the prototype. This test measured the instantaneous thrust and aerodynamic forces, the velocity of the wings, the rotational speed of the motor and the driving power usage in hovering flight. Different input powers were tested to compare their dynamic performance. Finally, the results of the tests for different extends of wings reciprocating at different frequencies were analyzed to study the performance of the umbrella-like wings. The results indicated that this type of propulsion can provide an efficient propelling force by oscillating modular umbrella-like wings symmetrically in counter phase at relative low frequencies; e.g., the thrust generated by the propulsion mechanism was 6.2 N for a constant extend of 0.50 m and a frequency of 1.76 Hz. The thrust increased as the frequency increased within a certain range. Umbrella-like wing generated an upward aerodynamic force when it was moving downwards. The wing generated less negative lift force than that traditional flapping wing generates when it was moving upwards. Either increasing the extent or improving the speed can enhance the aerodynamic force generated by the umbrella-like wing. The average aerodynamic force increased to 57.6% as the extend of the wing was increased from 0.50 m to 0.65 m for a moving speed of 2.10 m/s, and it increased to 60.4% as the moving speed was increased from 2.07 m/s to 2.53 m/s for a constant extend of 0.65 m. The thrust-to-power ratio of the propulsion mechanism ranged from 0.01 N/W to 0.04 N/W, it was larger than the experimental results of flexible wing of traditional flapping wing vehicles that ranged from -0.02 N/W to 0.01 N/W. The propulsion mechanism would obtain a better performance for larger wings. The thrust-to-power ratio increased to double as the extend of the wing was increased from 0.50 m to 0.65 m for an oscillating frequency of 0.95 Hz. Our research showed an efficient method to solve the problem of traditional propulsion which should flap wings at relatively high frequencies, and we can apply this new type of technology to the area of large-sized ornithopter. This work provides practical guidance for optimizing the structure design. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Flexible wings
Controlled terms:Aerodynamics - Automobile manufacture - Design - Flight dynamics - Machine design - Mechanical properties - Problem solving - Propellers - Propulsion - Research aircraft  - Vehicles - Wings
Uncontrolled terms:Different frequency - Dynamic performance - Flapping wing air vehicles - Mechanism design - Oscillating frequencies - Propulsion mechanisms - Propulsion performance - Propulsion technology
Classification code:601  Mechanical Design - 651.1  Aerodynamics, General - 652.1  Aircraft, General - 662.1  Automobiles - 951  Materials Science
Numerical data indexing:Force 6.20e+00N, Frequency 1.76e+00Hz, Frequency 9.50e-01Hz, Percentage 5.76e+01%, Percentage 6.04e+01%, Size 5.00e-01m, Size 5.00e-01m to 6.50e-01m, Size 6.50e-01m, Velocity 2.07e+00m/s to 2.53e+00m/s, Velocity 2.10e+00m/s
DOI:10.11975/j.issn.1002-6819.2016.15.005

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 9>

Accession number:20163302706361
Title:Error model and verification of three degrees of freedom parallel mechanical leg on hexapod drilling robot
Authors:Rong, Yu (1, 2); Liu, Shuangyong (2); Han, Yong (2); Lin, Feng (2); Li, Kai (2) 
Author affiliation:(1) College of Mechanical Dlectronical and Engineering, Hebei Normal University of Science and Technology, Qinhuangdao; 066004, China; (2) CiTiC Dicastal Wheel Manufacturing Co., Ltd., Qinhuangdao; 066004, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:18-25
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the process of large passenger aircraft manufacturing and assembly, a lot of drilling and milling work needs to be done. Due to the limitation of the structure, the traditional drilling and milling machines can't be used in the drilling and milling work of large passenger aircraft. The hexapod robot with motorized spindle on its trunk is very suitable for the drilling and milling work. The hexapod robot can crawl on the aircraft's exterior surface through suckers on its foot. So the hexapod robot can do the drilling and milling work by the motorized spindle on its trunk. For the hexapod drilling robot, a new type of 3-DOF (3 degrees of freedom) mechanical leg based on (U+UPS)P+UPS parallel mechanism is presented (U, P and S represent universal pair, prismatic pair and spherical joint, respectively). The decoupling performance of the mechanical leg's motions is very good, and its 2 rotational motions are completely decoupled. Its control algorithm is very simple, so it can be real-time controlled very easily. In order to improve the accuracy of the hexapod drilling robot, the error modeling and evaluation method of the mechanical leg is established. The prototype is manufactured by precision design, and the error calibration experiment is done. First, using the vector chain method, the error vector constraint equation is established and the error propagation model is obtained. Using the error model, the mechanical leg's output errors with a given set of error sources can be calculated. Also, the mechanical leg's tolerance allocation with a given set of output errors can be calculated too. In order to evaluate the error transfer performance of the mechanical leg, a set of error sensitivity evaluation indices are defined, and the distribution of error sensitivity evaluation indices in the mechanical leg's workspace is drawn. It reveals that the error transfer characteristics of the mechanical leg are good in the central area of the workspace. Based on the set of indices, the error sensitivity of the mechanical leg is evaluated. Based on the comprehensive consideration of various performance indices of the mechanical leg, the structure parameters are designed by Monte Carlo method. The parameters are as follows: the distance between the universal joints which are connected to the fixed platform is 200 mm, the length of the middle connecting rod is 70 mm, the length of the end connecting rod is 50 mm, and the distance between the middle connecting rod and the main branch's universal joint is 450 mm. Based on this set of structural parameters, the mechanical leg's prototype is manufactured. Finally, using high precision robot calibration system, the error calibration experiment of mechanical leg is done, and the error characteristics of the mechanical leg's prototype are obtained. Experimental results indicate that the deviations between the measured and the theoretical position error are less than 0.003 mm, the deviations between the measured and the theoretical attitude error are less than 0.05&deg;, and the deviations between the measured and the theoretical error sensitivity evaluation index are less than 0.05. So, the error of mechanical leg's prototype is in reasonable range, and the structure and parameters of the mechanical leg have been proved to be reasonable. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Errors
Controlled terms:Algorithms - Calibration - Connecting rods - Degrees of freedom (mechanics) - Error analysis - Experiments - Fighter aircraft - Fixed platforms - Machine tools - Mechanics  - Mechanisms - Milling (machining) - Models - Monte Carlo methods - Offshore oil wells - Robots - Transportation - Universal joints
Uncontrolled terms:Error characteristics - Error propagation model - High Precision Robot - Parallel mechanical legs - Sensibility - Three degrees of freedom - Tolerance allocation - Transfer characteristics
Classification code:511.2  Oil Field Equipment - 512.1.1  Oil Fields - 601.2  Machine Components - 601.3  Mechanisms - 603.1  Machine Tools, General - 604.2  Machining Operations - 652.1.2  Military Aircraft - 731.5  Robotics - 901.3  Engineering Research - 922.2  Mathematical Statistics - 931.1  Mechanics
Numerical data indexing:Size 2.00e-01m, Size 3.00e-06m, Size 4.50e-01m, Size 5.00e-02m, Size 7.00e-02m
DOI:10.11975/j.issn.1002-6819.2016.15.003

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 10>

Accession number:20163302706393
Title:Optimization of pipe form parameters of desiccant rotary wheels of dehumidification system for storage
Authors:Duan, Jieli (1); Zhang, Xinyu (2); L&uuml;, Enli (2, 3); Lu, Huazhong (3, 4); Hou, Keming (2) 
Author affiliation:(1) Engineering Fundamental Teaching and Training Center, South China Agricultural University, Guangzhou; 510642, China; (2) College of Engineering, South China Agricultural University, Guangzhou; 510642, China; (3) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou; 510642, China; (4) Guangdong Academy of Agricultural Sciences, Guangzhou; 510640, China 
Corresponding author:Lu, Huazhong(huazlu@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:255-260
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Controlling the humidity in environment is very important for qualities of storage. In order to improve the working performance of desiccant rotary wheels of dehumidification system for the storage and the relative humidity uniformity of the storage environment, a set of pipeline type wheel dehumidifying device was integrated into the existing dehumidification system in this study. By increasing pipeline type passage of dry air, the pattern of indoor air flow was rearranged from middle-in and bottom-out to pipe-in and bottom-out. In this study, hybrid rice seeds were used as the test material. To determine the dehumidifying effect of the modified system, a three-factor three-level orthogonal experiment for the prototype was carried out and the results were analyzed. Experiment was carried out at temperature of 25&#8451;, airflow velocity of 5 m/s, and cargo stacking in the intermediate bottom. For the 3 factors in the experiment, pipeline location was set as 1.25, 0.65 and 0.05 m, pipe diameter was set as 50, 40 and 32 mm, and number of holes on pipes was set as 5, 10 and 20. With the pipeline type wheel dehumidifying device, the relative humidity in the container could be decreased from 95% to 30%. When the pipeline was located at 0.05 m above the bottom of the container, the pipeline diameter was 50 mm, and the number of holes on pipes was 20. It was found this relative humidity distribution was the most uniform, and the coefficient of variance of relative humidity was 3.81%, which was about only 15% of the worst case. Because the position of the air supply pipe determined the revolving flow of the whole flow field. Meanwhile, it was found that the best dehumidifying effect occurred under the conditions that the pipeline location was 0.65 m, the pipe diameter was 40 mm, and the number of holes on pipes was 20. The capacity of the desiccant in combination of the pipeline location of 0.65 m, the pipe diameter of 40 mm, and the 20 holes on pipes was 71.74 g/(kg&middot;h), which was about twice of that in the worst case. The corresponding efficiency of the desiccant was 0.0906 g/(kg&middot;h&middot;kJ), which was 3 times that of the worst case. Taking into account the overall effect of the desiccant, more attention should be paid to the performance of the desiccant capacity and efficiency. The results show that the number of holes on pipes makes the strongest unique contribution to the capacity and efficiency of the desiccant, followed by the pipe diameter and the pipeline location. Overall, the research can provide guideline information for the optimization design of dehumidification system for the storage. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Humidity control
Controlled terms:Air - Containers - Driers (materials) - Energy storage - Energy utilization - Location - Optimization - Pipelines - Piping systems - Storage (materials)  - Wheels
Uncontrolled terms:Coefficient of variance - Dehumidification system - Humidity distribution - Optimization design - Orthogonal experiment - Rotary wheels - Uniformity - Working performance
Classification code:525.3  Energy Utilization - 525.7  Energy Storage - 601.2  Machine Components - 619.1  Pipe, Piping and Pipelines - 694.4  Storage - 803  Chemical Agents and Basic Industrial Chemicals - 804  Chemical Products Generally - 921.5  Optimization Techniques
Numerical data indexing:Percentage 1.50e+01%, Percentage 3.81e+00%, Percentage 9.50e+01% to 3.00e+01%, Size 3.20e-02m, Size 4.00e-02m, Size 5.00e-02m, Size 6.50e-01m, Velocity 5.00e+00m/s
DOI:10.11975/j.issn.1002-6819.2016.15.035

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 11>

Accession number:20163302706392
Title:Parameter optimization experiment of adjustable five rollers shrimp peeling machine
Authors:Zhang, Xiuhua (1); Zhao, Qinglong (1); Wang, Zehe (1); Yi, Jinggang (1); Wang, Jie (2) 
Author affiliation:(1) College of Mechanical and Electrical Engineering, Agricultural University of Hebei, Baoding; 071001, China; (2) College of Food Science and Technology, Agricultural University of Hebei, Baoding; 071001, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:247-254
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There is enormous quantity of shrimp in China and it has great value of development and utilization. The peeling of the shrimp is mainly by manual labor at present, and the mechanized peeling technology of shrimp in China is still on a preliminary?stage. Mechanical manipulation methods are being studied to improve the production efficiency and to extract the integral meat of shrimp. Shrimp processing time is relatively concentrated and labor resources are in shortage, which can not meet the needs of large-scale production of enterprises. Therefore the research of shrimp mechanical peeling has important significance and solving the problem of shrimp peeling mechanization is an important direction of development. Preliminary study results show that the method of roll-type extrusion peeling is good. Comparing the effects of dual-roller extrusion peeling and five-roller extrusion peeling, the peeling device with 5 rollers had the advantage of high peeling efficiency, so it would be widely applied for peeling shrimp. In order to further study the shrimp peeling machine and improve the work quality for the shrimp peeling machine, the adjustable five rollers peeling machine was designed. The study took the fresh Litopenaeus vannamei with a number between 70 and 80 per kilogram as the study object. In order to determine the operation parameters of the adjustable five rollers peeling machine, the response surface experiment with 4 factors and 5 levels was completed on the adjustable five rollers peeling machine. Four parameters, including rollers speed, rollers rotation angle, rollers V angle and rollers tilt angle were selected as the input variables, and peeling rate, meat yield and peeling time were selected as the output parameters. Quadratic orthogonal rotary regressive experimental design was employed to develop the second order polynomial regression model, which explained the relationship between the input and output parameters. By the Design-Expert 8.0.5b software, the corresponding mathematical regression model was established, the influence of significant factors on the quality of operation was analyzed, and the experimental parameters were optimized. The optimal combination of parameters determined was as follows: rollers speed was 25 r/min, rollers rotation angle was 315&deg;, rollers V angle was 130&deg; and rollers tilt angle was 18&deg;. From the results of predicting model, the average of peeling rate was 94.71%, the meat yield was 85.10% and the peeling time was 54.61 s. In order to verify the feasibility of the parameter matching, with the optimal parameters, the verification test of the machine was carried out. Before the experiments, all the shrimps should be under the pretreatment of -30&#8451; for 10 min, all the heads of the shrimps were cut, and the length of the back opening was 6 ranks (from Section 1 to 6). The results showed that, under the combination of optimization parameters, the average of peeling rate was 94.67%, the meat yield was 85.23% and the peeling time was 54.33 s. The experimental results had little difference with the results predicted by the model. Through the shrimp peeling experiments, the adjustable five rollers peeling machine was basically consistent with the technical requirement. The research results can provide reference for the peeling parameter optimization of the shrimps of all ranks. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:19
Main heading:Rollers (machine components)
Controlled terms:Efficiency - Equipment - Extrusion - Machinery - Meats - Peeling - Regression analysis - Rollers (roadbuilding machinery) - Shellfish
Uncontrolled terms:Combination of optimizations - Development and utilizations - Experimental parameters - Large scale productions - Mechanical manipulation - Parameter optimization - Second-order polynomial - Shrimp
Classification code:406  Highway Engineering - 461.9  Biology - 601.2  Machine Components - 822.3  Food Products - 901  Engineering Profession - 913.1  Production Engineering - 922.2  Mathematical Statistics
Numerical data indexing:Percentage 8.51e+01%, Percentage 8.52e+01%, Percentage 9.47e+01%, Rotational_Speed 2.50e+01RPM, Time 5.43e+01s, Time 5.46e+01s, Time 6.00e+02s
DOI:10.11975/j.issn.1002-6819.2016.15.034

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 12>

Accession number:20163302706383
Title:Preparation and properties analysis of polycaprolactone/polylactic acid blend for agricultural biodegradable film
Authors:Li, Xingong (1); Ji, Yuxin (1); Tang, Qian (1); Zhu, Lingbo (1) 
Author affiliation:(1) College of Materials Science and Engineering, Central South University of Forestry and Technology, Changsha; 410004, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:182-186
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Poly lactic acid (PLA) is a kind of environment-friendly high polymer material with the characteristics of biodegradability and good processability, which can be used in producing agricultural film. However, the PLA perform brittleness leads to several defects of PLA film, which might be overcome by addition of polycaprolactone (PCL). This study aimed to find the optimal PCL and PLA ratio for PCL/PLA blend preparation. The preparation and performance tests in the study were all completed in the key laboratory of bio-composite materials of College of Materials Science and Engineering in Central South University of Forestry and Technology in Changsha, Hunan. PCL and PLA mass ratio including 0: 100, 30: 70, 40: 60, 50: 50, 60: 40, and 100: 0 was designed. The PCL/PLA blend was prepared through melt blending and injection molding process. Measured indicators included mechanical properties such as tensile strength, tensile elongation at break and the impact strength. Meanwhile, the micro interface bonding, thermal stability, melting and crystallization behavior as well as the surface wetability of the PCL/PLA blend were tested and analyzed. The analysis of mechanical property tests showed that, with the increase of PCL mass fraction, the tensile strength of PCL/PLA blend decreased gradually, while the tensile elongation at break and impact strength increased first and then decreased. The blend tensile elongation at break and impact strength reached the maximum value of 11.2% and 6.3 MPa, respectively when the PCL mass fraction was 50%. Scanning electron microscopy analysis showed a poor micro interface bond, indicating an inferior compatibility between PLA and PCL. Moreover, it was found that the mechanical properties of PCL/PLA blend were influenced by both the kind and characteristics of the continuous phase of polyester. Thus the results that tensile fracture of blend with the 50% PCL presented the best bonding situation of the 2 continue phases were consistent with results of the mechanical property test. Thermogravimetry analysis showed that the PCL effectively reduced the pyrolysis rate of the blend, improved the pyrolysis temperature and the carbon content of blend increased with the increase of mass fraction of PLA. Differential scanning calorimeter analysis showed that, compared to PLA and PCL, PLA/PCL blend glass transition temperature, melting temperature and crystallization temperature had changed, but effect of the mass ratio on 3 kinds of temperature was not obvious. While the contact angle analysis showed that the contact angles of PCL/PLA blend increased compared to PCL and PLA, reducing the water wettability. When the mass ratio of PCL and PLA was 50: 50, the contact angle of PCL/PLA blend was highest (96.2&deg;). In a comprehensive consideration, PCL/PLA blend performed the best properties with the PCL and PLA mass ratio of 50: 50, and in the other words, the PCL modified the toughness of the composites effectively. The study could provide valuable information for biodegradable plastic film preparation. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:13
Main heading:Polycaprolactone
Controlled terms:Agriculture - Biodegradability - Biodegradable polymers - Blending - Bonding - Carbon - Contact angle - Crystallization - Differential scanning calorimetry - Electron microscopy  - Elongation - Film preparation - Fracture - Fracture mechanics - Glass transition - Impact strength - Injection molding - Lactic acid - Mechanical properties - Melting  - Molding - Pyrolysis - Scanning electron microscopy - Tensile strength - Thermogravimetric analysis
Uncontrolled terms:Biocomposite materials - Crystallization temperature - Differential scanning calorimeter analysis - Injection molding process - Materials science and engineering - Melting and crystallization - Poly lactic acid - Thermogravimetry analysis
Classification code:801  Chemistry - 801.2  Biochemistry - 802.2  Chemical Reactions - 802.3  Chemical Operations - 804  Chemical Products Generally - 804.1  Organic Compounds - 815.1  Polymeric Materials - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1  Mechanics - 931.2  Physical Properties of Gases, Liquids and Solids - 944.6  Temperature Measurements - 951  Materials Science
Numerical data indexing:Percentage 1.12e+01%, Percentage 5.00e+01%, Pressure 6.30e+06Pa
DOI:10.11975/j.issn.1002-6819.2016.15.025

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 13>

Accession number:20163302706376
Title:Influence of outer river flood level on drainage discharge in plain lake areas
Authors:Luo, Wenbing (1); Wang, Xiugui (2); Shi, Deliang (1); Yao, Fuqi (1); Qian, Long (2); Wang, Shuhai (3); Ke, Zhigang (3) 
Author affiliation:(1) Institute of Agricultural Water Conservancy, Changjiang River Scientific Research Institute, Wuhan; 430010, China; (2) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan; 430072, China; (3) Water Conservancy Bureau of Jingzhou City, Jingzhou; 434020, China 
Corresponding author:Wang, Xiugui(wangxg@whu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:126-132
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The accurate simulation of the process of runoff yield and concentration in the drainage area is of important significance for the reasonable determination of the scale of drainage projects and their orderly operation. The Luoshan drainage area in Four-lake Watershed in Hubei Province was selected as the research area. The runoff yield and concentration model at a drainage area scale was developed by coupling SCS with MIKE11. The coupled model was calibrated with the measured water level of Luoshan pumping station in 1980 and 1983, and validated with the measured water level in 1991 and 1996. Results showed that the relative errors between simulated and measured water levels were -0.20% and -0.40% respectively, the correlation coefficients were 0.980 and 0.952, and the efficiency coefficients were 0.949 and 0.849 respectively during the calibration periods (1980 and 1983). The relative errors between simulated and measured water levels were -0.10% and 1.70% respectively, the correlation coefficients were 0.919 and 0.967, and the efficiency coefficients were 0.782 and 0.906 respectively during the validation periods (1991 and 1996). Good agreements between simulated and measured water levels indicated that the coupled model was appropriate to simulate the process of runoff yield and concentration in the drainage area. Then the coupled model was used to analyze the influence of flood levels of the outer river on drainage discharge with six scenarios, which were combinations of two design storms with three flood levels of the outer river. Two design storms, 175.57 mm and 212.07 mm, were corresponding to three-day storms with return periods of 5 years and 10 years respectively. And three flood levels of the outer river, 32.63 m, 33.45 m and 30.68 m, were corresponding to the maximum five-day mean water levels in flood season with return periods of 5 years and 10 years, and the design level of the outer river of the pumping station. The simulation results showed that for the same storm, the higher flood level of the outer river was, the larger the required pumping drainage discharge was, and vice versa. Furthermore, the adverse influence of the flood level of the outer river on drainage was greater with the rising of flood level of the outer river. If the drainage discharge was simulated according to the pump characteristic curve, the simulation accuracy of drainage discharge could be improved between 19.6% and 53.8%. The coupled model could be applied as a useful tool for the accurate determination of the capacity of drainage pumping stations in this drainage area which was affected by the flood level of the outer river. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Water resources
Controlled terms:Calibration - Drainage - Efficiency - Floods - Lakes - Models - Pumping plants - Pumps - Rivers - Runoff  - Storms - Water levels
Uncontrolled terms:Correlation coefficient - Drainage area - Drainage pumping station - Efficiency coefficient - Flow - Four-lake watersheds - Pump characteristics - Pumping stations
Classification code:443.3  Precipitation - 444  Water Resources - 444.1  Surface Water - 446  Waterworks - 618.2  Pumps - 913.1  Production Engineering
Numerical data indexing:Age 5.00e+00yr, Percentage -1.00e-01%, Percentage -2.00e-01%, Percentage -4.00e-01%, Percentage 1.70e+00%, Percentage 1.96e+01%, Percentage 5.38e+01%, Size 1.76e-01m, Size 2.12e-01m, Size 3.07e+01m, Size 3.26e+01m, Size 3.35e+01m, Age 1.00e+01yr
DOI:10.11975/j.issn.1002-6819.2016.15.018

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 14>

Accession number:20163302706373
Title:Design of asphalt mixture stirring roller and simulation and validation of heating efficiency
Authors:Ma, Dengcheng (1); Li, Xuan (1); Li, Zong (1); Li, Ping (1) 
Author affiliation:(1) National Engineering Laboratory for Highway Maintenance Equipment, Chang'an University, Xi'an; 710064, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:104-109
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The asphalt pavement repair has the requirements of fast reaching the site, timely repair, and opening to traffic soon. In order to meet the requirements, the heating efficiency of asphalt pavement maintenance vehicle is very important. The existing heating asphalt mixture has low heating efficiency and can't meet the increasing need of asphalt pavement repair. In order to solve the problems of lower heating efficiency, excessive radiation and other defects of the domestic asphalt pavement maintenance vehicle, and to improve the heating quality and heating efficiency of asphalt mixture in asphalt pavement maintenance, a new type of heating and stirring roller of asphalt pavement maintenance vehicle is proposed. The Fluent software is used to simulate the heating efficiency of the heating roller, which provides the theoretical basis and research methods for the design of the heating drum of asphalt mixture and the temperature field analysis. The asphalt mixture heating roller with stirring function is designed, the roller structure and thermal insulation layer are calculated, and the design calculation method is given. By using the Fluent simulation software, the heating process of asphalt mixture is simulated by using standard k-&Epsilon; double-equation model and heat transfer model. Through numerical simulation and analysis, the three-dimensional (3D) analysis model of asphalt mixture flow and heat is established. Meantime, the simulation analysis and experimental verification are carried out. The results show that the asphalt mixture has high heating efficiency and good heating uniformity using the designed stirring and heating roller. In the heating process, the bottom temperature is always higher than that of the intermediate layer and the surface layer. At the end of the heating, temperature difference between the surface and the bottom is about 1&#8451;, asphalt mixture has a uniform distribution of temperature which has reached 160&#8451;, and heating effect is good without temperature segregation. Compared with the traditional heat conduction oil heating method, the heating time can be shortened from 8 h to 35 min, and the heating efficiency of the heating roller is greatly increased. In order to further analyze the influence of the structure of the heating roller on the heating efficiency, the rotating speed of the roller is set to 5 r/min, and the influence of the height of the blade and the spiral angle on the heating efficiency is analyzed. Through the analysis of the coupling simulation of roller blade parameters, it is found that when the rise angle of the helical blade is 68&deg; and the blade height is 300 mm, the mixed material heating efficiency is the highest. Finally, in order to verify the simulation results of the heating drum structure design and heating efficiency, the specific test is carried out. The initial temperature of asphalt mixture is 25&#8451;, the quality is 2000 kg, and the time heating to the mixture temperature of 160&#8451; needs 35 min. From the experimental results, the actual heating time is 35 min and the simulation result is 32 min, which shows that the simulation result is consistent with the actual one. The study can provide theoretical basis for the design of asphalt pavement maintenance vehicle heating device. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:14
Main heading:Asphalt mixtures
Controlled terms:Asphalt - Asphalt pavements - Computer software - Design - Efficiency - Heat conduction - Heat transfer - Heating - Maintenance - Mixtures  - Repair - Rollers (machine components) - Surface segregation - Temperature - Temperature distribution - Thermal insulation - Vehicles
Uncontrolled terms:Experimental verification - Heating efficiencies - Simulatio nanalysis - Simulation and validation - Temperature field analysis - Temperature segregation - Thermal insulation layer - Three-dimensional (3D) analysis
Classification code:411.1  Asphalt - 413.2  Heat Insulating Materials - 601.2  Machine Components - 641.1  Thermodynamics - 641.2  Heat Transfer - 723  Computer Software, Data Handling and Applications - 913.1  Production Engineering - 913.5  Maintenance - 931.3  Atomic and Molecular Physics
Numerical data indexing:Mass 2.00e+03kg, Rotational_Speed 5.00e+00RPM, Size 3.00e-01m, Time 1.92e+03s, Time 2.10e+03s, Time 2.88e+04s to 2.10e+03s
DOI:10.11975/j.issn.1002-6819.2016.15.015

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 15>

Accession number:20163302706391
Title:Identification and determination of its critical values for influencing factors of cultivated land reclamation strength in region of Brahmaputra River and its two tributaries in Tibet
Authors:Tao, Juanping (1); Wang, Yukun (1); Liu, Fenggui (1, 2); Zhang, Yili (2, 3); Chen, Qiong (1); Wu, Lin (1) 
Author affiliation:(1) College of Biologic Geographic Sciences, Qinghai Normal University, Xining; 810008, China; (2) Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing; 100101, China; (3) CAS Center for Excellence in Tibetan Plateau Earth Sciences, Beijing; 100101, China 
Corresponding author:Liu, Fenggui(lfg_918@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:239-246
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The region of Brahmaputra River and its two tributaries is one of the important typical agricultural area in Tibet Plateau. The development of agriculture depends on natural environment strongly which makes the cultivated land area is narrow. The arable land is only distributed in valley and its restrictive factors are prominent. To identify and measure the influence factors of cultivated land distribution has a realistic significance for the agricultural development and cultivated land reconstruction. According to this, the paper used the existing data in the region of Brahmaputra River and its two tributaries to analyze the regularity distribution and its reclamation strength in different altitude and geomorphic unit. We found that the proportion of grids whose reclamation ratio was 10%-30% was the biggest and it accounted for 29.39% of total grids with cultivated land. The cultivated land was mainly distributed on the diluvial plain in wide river valley with the altitude of 3700-4100 m. The proportion of its arable land was up to 59.85%. Partial least squares regression (PLS) is a method of multivariate statistical data analysis with the characteristics of multiple linear regression analysis, canonical correlation analysis and principal component analysis method. To explore the relationship between cultivated land and natural, social and economic influencing factors, we took the proportion of cultivated land in each 1 km &times; 1 km grid as the dependent variable, and 12 impacting factors of cultivated land as the independent variable, which consisted of elevation, slope, aspect, precipitation, accumulated temperature of higher than 0&#8451;, average July temperature, average January temperature, solar radiation, soil organic matter content, soil thickness, distance from the nearest town and distance from the nearest river, and established the PLS regression model, using the variable projection importance index to measure the interpretation capacity of various factors on the variable. The results showed that the influence of 12 factors on the intensity of cultivated land reclamation was slope &gt; solar radiation &gt; average July temperature &gt; elevation &gt; precipitation &gt; distance from the nearest river &gt; average January temperature &gt; distance from the nearest town &gt; accumulated temperature of higher than 0&#8451; &gt; soil organic matter content &gt; soil thickness &gt; aspect. The variable projection importance index value of slope was 2.2269, and slope had the strongest explanation and was the most important influencing factor to the land distribution. It concerned the difficulty level of land reclamation; the more flat the area, the easier to reclaim. Heat condition of cultivated land distribution also had an important influence. The values of average July and January temperature were 1.0967 and 0.8187, respectively, and both of them had strong explanation to cultivated land. The elevation was also important with the value of 1.0954. Altitude limited the distribution of cropland, and by influencing the heat change in vertical direction, it influenced the distribution of cultivated land. Because of the river valley landform, accessibility factors included distance from the nearest town and river were ranked in front in the influencing factors, and their values were respectively 0.7588 and 0.8442, respectively. The influence of soil factors on the cultivated land distribution was not obvious. It reflected that the distribution of cultivated land was mainly controlled by topography and climate. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Land reclamation
Controlled terms:Agriculture - Biogeochemistry - Biological materials - Land use - Landforms - Least squares approximations - Linear regression - Multivariant analysis - Organic compounds - Principal component analysis  - Reclamation - Regression analysis - Rivers - Soils - Solar radiation - Topography
Uncontrolled terms:Brahmaputra River - Canonical correlation analysis - Cultivated lands - Influencing factors - Multiple linear regression analysis - Multivariate statistical data analysis - Partial least squares regression - Principal component analysis method
Classification code:403  Urban and Regional Planning and Development - 442.2  Land Reclamation - 461.2  Biological Materials and Tissue Engineering - 481.1  Geology - 481.2  Geochemistry - 483.1  Soils and Soil Mechanics - 657.1  Solar Energy and Phenomena - 804.1  Organic Compounds - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921.6  Numerical Methods - 922  Statistical Methods - 922.2  Mathematical Statistics - 951  Materials Science
Numerical data indexing:Percentage 1.00e+01% to 3.00e+01%, Percentage 2.94e+01%, Percentage 5.99e+01%, Size 1.00e+03m, Size 3.70e+03m to 4.10e+03m
DOI:10.11975/j.issn.1002-6819.2016.15.033

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 16>

Accession number:20163302706384
Title:Compensation design and performance test of shadow area at bottom of thermoelectric generation sheet
Authors:Wang, Lishu (1); Ding, Xiuzeng (1); Feng, Xingrong (1); Yang, Junjie (1); Ma, Yuqiu (1); Liang, Qiuyan (1, 2) 
Author affiliation:(1) Institute of Electrical and Information, Northeast Agricultural University, Harbin; 150030, China; (2) Mechanical Engineering School of Jia Mu Si University, Jia Mu Si; 154007, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:187-196
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:When using the principle of collecting light to produce thermoelectric power, some lights can not arrive condenser plate due to the fact that light travels in straight line and some are blocked by the battery plate, so the bottom of the battery plate produces shadow area, resulting in the overall output power decreasing. In order to improve the overall output power, based on the example of the parabolic condenser plate, this paper proposed the planar type and parabolic type design to make up the shadow area. Based on the construction model, the parameters of shadow area were acquired, and thus the optimal compensation size and setting angle of planar and parabolic reflector were obtained. After that, the compensation design of planar and parabolic reflector was made. The best solution of planar compensation was as follows. The size of 2 planar reflectors was &radic;2 times the width of shadow region, the left planar reflector's setting angle was 135&deg;, and the right planar reflector's setting angle was 45&deg;. If there was a deviation angle, the setting angle for the left and right reflector would change to 135&deg; minus the deviation angle and 45&deg; minus the deviation angle accordingly, and at the same time, the left planar reflector must be increased to a certain height. Also, the related parameters of parabolic compensation were obtained, such as arc length, placement angle and aperture size. In the case of planar compensation, the simulation was carried out with Tracepro. By setting different size and setting angle in Tracepro, the correctness of the theoretical compensation method was proved. And under the same conditions, the effects of the 2 kinds of compensation methods were compared. The results showed that the planar reflector's compensation illumination range was about 1 W/m², and the parabolic reflector's illumination range was about 2 W/m², so the performance of parabolic reflector was better than that of planar reflector. By compensation, the shadow area at the bottom of the cell panel was well eliminated. In order to verify the simulation results, experiments were carried out at Northeast Agricultural University on October 21, 2015. Measurement parameters included ambient temperature, surface temperature of heat collector, temperature of cold end, and the output voltage and current. The measure period was from 09: 00 to 14: 00. The energy of hot end of the thermoelectric module came from the parabolic condenser plate, and the cold end used the natural wind cooling. It should be pointed out that the outside influence factors were ignored. Compared with no compensation, the temperature of thermoelectric generator (TEG) under planar compensation and parabolic compensation had a significant increase in the hot end, and the parabolic compensation and planar compensation ranged from 315.14 to 357.46 K and from 312.6 to 453.4075 K respectively, while the temperature of the cold end was almost constant and ranged from 285.12 to 290.47 K. The output power of no compensation, planar compensation and parabolic compensation ranged from 20.05 to 28.94 W, from 20.36 to 29.78 W and from 21.04 to 30.35 W respectively. The originality of this paper was the research on the effect of the compensation of shadow area at the bottom of solar thermoelectric power generation sheet on overall output power. In conclusion, the work above shows that the overall output power is improved by effective compensation, more precisely, parabolic compensation is better than planar compensation. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Reflection
Controlled terms:Atmospheric temperature - Compensation (personnel) - Design - Electric batteries - Headlights - Power generation - Solar energy - Thermoelectric equipment - Thermoelectric power - Thermoelectricity
Uncontrolled terms:Bottom shadow - Measurement parameters - Optimal compensations - Out power - Surface temperatures - Thermo-electric modules - Thermoelectric generation - Thermoelectric generators
Classification code:443.1  Atmospheric Properties - 615.4  Thermoelectric Energy - 657.1  Solar Energy and Phenomena - 662.4  Automobile and Smaller Vehicle Components - 701.1  Electricity: Basic Concepts and Phenomena - 702.1  Electric Batteries - 912.4  Personnel
Numerical data indexing:Power 2.01e+01W to 2.89e+01W, Power 2.04e+01W to 2.98e+01W, Power 2.10e+01W to 3.04e+01W, Surface_Power_Density 1.00e+00W/m2, Surface_Power_Density 2.00e+00W/m2, Temperature 2.85e+02K to 2.90e+02K, Temperature 3.13e+02K to 4.53e+02K, Temperature 3.15e+02K to 3.57e+02K
DOI:10.11975/j.issn.1002-6819.2016.15.026

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 17>

Accession number:20163302706369
Title:Eccentric compression behavior of thin-walled steel-tube/bamboo-plywood assembling short hollow column with binding bars
Authors:Zhao, Weifeng (1); Gu, Wei (1); Zhou, Jing (2); Long, Zhilin (1) 
Author affiliation:(1) College of Civil Engineering and Mechanics, Xiangtan University, Xiangtan; 411105, China; (2) State Key Laboratory of Subtropical Building Science, South China University of Technology, Guangzhou; 510640, China 
Corresponding author:Long, Zhilin(longzl@xtu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:75-82
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The development of laminated-bamboo has broadened the application range of bamboo material in the field of structural engineering. An assembling hollow column parallel to the fiber texture is composed of square thin-walled cold-formed steel-tube and bamboo-plywood by the fastening of the transverse binding bars and structural adhesive. The thin-walled steel-tube/bamboo-plywood assembling short hollow column with binding bars (SBCCBs) are a new type of steel/bamboo composite with excellent physical and mechanical properties. Multi-layered high-strength bamboo plywood forms the primary body in the SBCCB that is subjected to compressive forces, and the square thin-walled steel tube only serves as a liner. Large numbers of bamboo are used, which reduce the manufacturing cost of the composite columns and result in a relatively high load-bearing capacity. The failure modes, bearing capacity and influence factors of SBCCB subjected to eccentric compression loading, were investigated by the test of nine short specimens. The test results indicated that the compressive failure of specimens were primarily the gluing failure at the column end and the tension side of specimen, the gluing and debonding failure of the matrix interfaces in the middle of column between binding bars and the compressive broken of bamboo plywood material. The ultimate bearing capacity of SBCCB generally increased as the net cross-sectional area of gluing bamboo and hollow ratio increased, decreased as the slenderness ratio and the loading eccentricity increased. The thin-walled steel-tube embedded in the laminated bamboo column can enlarge the cross sectional area of composite column, and reduce the slenderness ratio and the loading eccentricity increased, which effectively improved the stability and ultimate bearing capacity of SBCCBs subjected to compression loading. The transverse binding bars forming the ferrule effect with the thin-walled steel-tube can effectively slow the gluing failure of SBCCB, changed the ultimate buckling mode and advantageously improved the compressive bearing capacity of specimens. The local buckling deformation decreased as the binding bars spacing decreased and can keep in a small range when the relative spacing ratio of horizontal binding bars to sectional size was below three. Compared to thin-walled steel-tube/bamboo-plywood assembling hollow column without the horizontal binding bars, the ultimate bearing capacity of SBCCB can be improved by 17.64%. A calculating model for the eccentric compressive bearing-capacity of SBCCBs, which can serve as a guideline for engineering applications, was obtained by nonlinear regression analysis of the test data, and the maximum error between the estimators based on the formula and the experimental results was about 8%. The overall results showed that the thin-walled cold-formed steel-tube and bamboo-plywood can form a composite structural element with good compressive performance, and the average compressive strength of this batch test specimens was 18.54 MPa. SBCCB specimens showed an excellent compressive performance and can be used as the vertical bearing element of the multi-story bamboo wood building structure. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:18
Main heading:Thin walled structures
Controlled terms:Bamboo - Bearing capacity - Bins - Buckling - Compression testing - Compressive strength - Gluing - High strength steel - Interfaces (materials) - Laminated composites  - Laminating - Loads (forces) - Plywood - Regression analysis - Safety engineering - Steel fibers - Studs (structural members) - Tubes (components) - Tubular steel structures - Wood products  - Wooden buildings
Uncontrolled terms:Bamboo plywoods - Binding bars - Eccentric compression - Hollow columns - Thin-walled steels
Classification code:402  Buildings and Towers - 408  Structural Design - 408.2  Structural Members and Shapes - 545.3  Steel - 619.1  Pipe, Piping and Pipelines - 694.4  Storage - 811.1  Pulp and Paper - 811.2  Wood and Wood Products - 816.1  Processing of Plastics and Other Polymers - 819.4  Fiber Products - 914  Safety Engineering - 922.2  Mathematical Statistics - 951  Materials Science
Numerical data indexing:Percentage 1.76e+01%, Percentage 8.00e+00%, Pressure 1.85e+07Pa
DOI:10.11975/j.issn.1002-6819.2016.15.011

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 18>

Accession number:20163302706400
Title:Continuous production of glycyrrtinic acid 3-O-mono-&beta;-D-glucuronide by immobilized cells
Authors:Wang, Caixia (1); Zhang, Tengjiang (2); Xiao, Yuqing (2); Feng, Xudong (2); Li, Chun (1, 2) 
Author affiliation:(1) School of Chemistry and Chemical Engineering, Shihezi University, Shihezi; 832003, China; (2) School of Life Science, Beijing Institute of Technology, Beijing; 100081, China 
Corresponding author:Li, Chun(lichun@bit.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:301-307
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Microbial immobilization is widely used in many areas such as bioengineering, biochemical separation and analysis. Glycyrrhizin (GL) can be transformed into glycyrrtinic acid 3-O-mono-&beta;-D-glucuronide (GAMG) by Penicillium purpurogenum Li-3 screened in the previous study. Penicillium purpurogenum Li-3 cells were immobilized into calcium alginate beads for GAMG production. However, the low mechanical strength and thus poor utilizable properties of the calcium lginate beads limited their applications. The mechanical strength of calcium alginate beads was improved by adding natural substances as well as chemical treating. Subsequently, the catalytic activities of the modified calcium alginate immobilized cells were characterized. At last, the continuous production of GAMG by modified immobilized cells in a self-designed packed bed reactor was further investigated. The obtained results were as follows: Firstly, diatomite was confirmed to be useful for improving the mechanical strength of calcium alginate beads with an optimal concentration of 4%. The so obtained modified immobilized cells were reused for 23 times in shake flask experiments. Subsequently, the modified immobilized cells were employed for GAMG production. After 48 h reaction, the output of GAMG was up to 1.62 g/L and the conversion of GL was 54%. The cost of the added diatomite was relatively low so that it can be used for further large-scale production. Secondly, the effects of pH, temperature and synergistic agent Tween-80 on the conversion efficiency and storage stability of the modified immobilized cells were studied. The results showed that the modification of immobilized cells made no difference on their pH and temperature, which were 5.4 and 35&#8451;, respectively. However, the enzyme activity was enhanced compared with the original immobilized cells. In detail, the conversion efficiency of GL by the modified immobilized cells was improved when 0.12% Tween-80 was added into the substrates, leading to the increase of GAMG output by 44% compared with that in substrates without Tween-80 supplemented. On the other hand, only 30% of the enzyme activity was lost in the modified immobilized cells when stored in physiological saline for 6 weeks at 4&#8451; while the free normal cells began autolysis after 2 weeks with the enzyme activity decreased to 34%. The enhanced and higher storage stability of the modified immobilized cells contributed to the continuous production. Finally, the influences of substrates concentrations and flow rates on the production of GAMG by the modified immobilized cells in packed bed reactor followed by the continuous production of GAMG were studied. The reactor was packed with 440 mL modified immobilized cells and the porosity was 0.55. Subsequently, the so constructed packed reactor was employed for GAMG production. The highest conversion efficiency of GL was up to 33.5% with GAMG output of 0.19 g/L, which was obtained when the balance time of batch reaction was 24 h with 0.72 g/L GL supplemented as substrates at a flow rate of 0.34 mL/min. Furthermore, continuous production of GAMG by the modified immobilized cells in an advanced packed bed reactor was explored. With a retention time of 27 h, the modified immobilized cells worked continuously for 20 d and maintained high enzyme activity. In this way, the daily output of GAMG was approximately 0.193 g/L with the conversion efficiency of 34% from GL and the space-time yield of 13.7 &mu;mol/(L&middot;h). Continuous production of GAMG by the modified immobilized cells in an advanced packed bed reactor laid the foundation for the efficient synthesis of GAMG from GL by whole-cell method. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Cells
Controlled terms:Acidity - Alginate - Antigen-antibody reactions - Calcium - Catalyst activity - Cell culture - Chemical reactors - Conversion efficiency - Cytology - Efficiency  - Enzyme activity - Enzymes - Packed beds - pH - Substrates
Uncontrolled terms:Biotransformation - GAMG - Immobilized cells - Large scale productions - Microbial immobilization - Packed bed reactor - Shake-flask experiments - Substrates concentration
Classification code:461  Bioengineering and Biology - 525.5  Energy Conversion Issues - 549.2  Alkaline Earth Metals - 801.1  Chemistry, General - 802.1  Chemical Plants and Equipment - 803  Chemical Agents and Basic Industrial Chemicals - 804  Chemical Products Generally - 804.1  Organic Compounds - 913.1  Production Engineering
Numerical data indexing:Age 1.15e-01yr, Age 3.84e-02yr, Mass_Density 1.62e+00kg/m3, Mass_Density 1.90e-01kg/m3, Mass_Density 1.93e-01kg/m3, Percentage 1.20e-01%, Percentage 3.00e+01%, Percentage 3.35e+01%, Percentage 3.40e+01%, Percentage 4.00e+00%, Percentage 4.40e+01%, Percentage 5.40e+01%, Time 1.73e+05s, Time 8.64e+04s, Time 9.72e+04s, Volume 4.40e-04m3
DOI:10.11975/j.issn.1002-6819.2016.15.042

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 19>

Accession number:20163302706390
Title:Spatiotemporal responses of runoff to land use change in Wei River Basin
Authors:Li, Yunyun (1); Chang, Jianxia (1); Wang, Yimin (1); Jin, Wenting (1); Bai, Xia (2) 
Author affiliation:(1) State Key Laboratory Base of Eco-hydraulic in Arid Area, Xi'an University of Technology, Xi'an; 710048, China; (2) Department of Mechanical and Vehicle Engineering, Bengbu College, Bengbu; 233030, China 
Corresponding author:Chang, Jianxia(chxiang@xaut.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:232-238
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Change in land use impacts the runoff availability to a large extent, which in turn, influences the surface and groundwater characteristics in a drainage area, and hence easily leads to the occurrence of droughts or floods in the basin. Therefore, it is essential to study the runoff response to land use change of a drainage basin on sub-basin level in particular, which has significant importance for planning land use patterns rationally and controlling watershed extreme hydrological events effectively. The Wei River basin (WRB), a typical arid and semi-arid region in northwest China, was selected as the study area and divided into 5 sub-basins. The main goal of current study was to investigate the spatiotemporal runoff responses to land use change in the WRB at sub-basin level. The change characteristics of land use in 1985, 1995 and 2005 in WRB were firstly analyzed with the transformation matrix. The Soil and Water Assessment Tool (SWAT) was calibrated for a baseline period of 1978-1986. Based on the results of land use change, 5 land use change scenarios were set in this paper. Then the calibrated SWAT model was run under these land use change scenarios by holding other data (e.g., meteorological and soil data) constant. The spatial runoff responses to land use change at both yearly and seasonal scales were analyzed based on the SWAT outputs. The results showed that: 1) The SWAT model had suitable application in the WRB with R²of higher than 0.6, Nash-Suttcliffe (Ens) of higher than 0.5 and relative error (Re) of lower than 20%, which indicated that the SWAT model could be used to study the impact of land use change on runoff variation in the WRB; 2) The main land use types of WRB were farmland, woodland and grassland which accounted for 98% of the whole basin area with high transfer frequency in space, while their area change percentages were all less than 10%; the total area of other land use types was small, but their change rates were all approximate to 40% and they were mainly transformed into cultivated land; 3) The contribution of land use change to runoff variation on decade scale in 5 subzones was less than 15%; the magnitudes of yearly discharge in 3 extreme land use scenarios in Beiluo basin were woodland &gt; farmland &gt; grassland, and farmland &gt; grassland &gt; woodland in other 4 basins; 4) For the conversion of farmland to woodland scenario, the yearly runoff in Beiluo basin increased while that in other 4 sub-basins decreased, and the conversion's impacts on the yearly runoff in the mainstream were greater than that in the tributary; for the conversion of farmland to grassland scenario, the yearly runoff in 5 sub-basins was all decreased, and the yearly runoff in the middle and lower reaches of the mainstream as well as the Jing River basin among the tributaries was decreased more significantly than other sub-basins; 5) Generally, the response degrees of seasonal runoff in the conversion of farmland to woodland scenario were higher than that in the conversion of farmland to grassland scenario; compared to other 3 kinds of seasonal runoff (i.e. spring, summer and autumn runoff), the winter runoff showed the most sensitive variation in both scenarios; the winter runoff decreased in the Jing River basin but increased in other basins in the scenario of returning farmland to forest, while it decreased in the tributary but increased in the mainstream in the scenario of returning farmland to grassland. The research results can play extremely important roles on the improvement of the ecological environment and the control of hydrological extreme drought events, and can also help to provide valuable reference for the watershed land use pattern's planning and integrated management in WRB. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Land use
Controlled terms:Calibration - Catchments - Drought - Farms - Forestry - Groundwater - Hydrology - Linear transformations - Models - Rivers  - Runoff - Watersheds
Uncontrolled terms:Arid and semi-arid regions - Ecological environments - Extreme hydrological events - Scenario analysis - Soil and water assessment tool - Spatiotemporal response - Transformation matrices - Wei river
Classification code:403  Urban and Regional Planning and Development - 444  Water Resources - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921.3  Mathematical Transformations
Numerical data indexing:Percentage 2.00e+01%, Percentage 4.00e+01%, Percentage 9.80e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.032

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 20>

Accession number:20163302706388
Title:Combustion characteristic and kinetics analysis of hydrochars
Authors:Fan, Fangyu (1, 3, 4); Xing, Xianjun (1, 2); Shi, Suwei (1); Zhang, Xianwen (1); Zhang, Xuefei (1); Li, Yongling (1); Xing, Yongqiang (1) 
Author affiliation:(1) Advanced Energy Technology and Equipment Research Institute, Hefei University of Technology, Hefei; 230009, China; (2) National City Energy Measurementcenter(Anhui), Hefei; 230051, China; (3) School of Chemistry and Chemical Engineering, Hefei University of Technology, Hefei; 230009, China; (4) The College of Forestry, Southwest Forestry University, Kunming; 650224, China 
Corresponding author:Xing, Xianjun(xxianjun@mail.ustc.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:219-224
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China is rich in agricultural and forestry resources, and thus biomass energy has broad prospects for development. Biomass energy utilization technologies are mainly divided into curing molding, thermo-chemical conversion and biochemical conversion. Hydrothermal carbonization (HTC) is one of the thermo-chemical conversion methods. HTC is very suitable to transform wet biomass feedstocks into carbon- rich solid fuels without drying the biomass, commonly referred to as hydrochars, whose physicochemical properties are comparable to that of coal. Sawdust and corn straw, as the representative of woody biomass and herbaceous biomass, respectively, were selected to produce hydrochars accordingly through hydrothermal carbonization under the condition of 230&#8451;, 30 min, and gas flow rate of 60 mL/min (the volume ratio of N<inf>2</inf>to O<inf>2</inf>was 4:1). Result indicated that the energy density of hydrochars was greatly improved, and could be used as solid fuel. Combustion characteristics of the hydrochar are different from biomass and biochar when produced at high temperature. Thermogravimetric (TG) analysis was used to investigate the combustion characteristics and kinetics of sawdust hydrochars and corn straw hydrochars. The influences of different heating rates (10, 20 and 40&#8451;/min) on hydrochar combustion behavior were analyzed, while raw material was investigated for the comparison at heating rate of 20&#8451;/min, too. The combustion characteristic parameters and the kinetic parameters were determined. The results indicated that: 1) The combustion weight loss of biomass and the hydrochar was focused on the burning process of the volatile matter and coke respectively, the ignition temperature and burnout temperature moved to the high temperature zone, and the integrated combustion characteristic index increased when the heating rate increased; 2) Integrated combustion characteristic index of sawdust hydrochars and corn straw hydrochars was increased by about 9 times and 7 times at 40&#8451;/min respectively compared to raw biomass, and integrated combustion characteristic index of sawdust hydrochars was much bigger than corn straw hydrochars; 3) At the heating rate of 20&#8451;/min, integrated combustion characteristic index of sawdust hydrochars and corn straw hydrochars was decreased a little; 4) The combustion kinetics analysis of hydrochars was performed using the first order reaction kinetics model and the integral method; all correlation coefficients of the fitting curves were greater than 0.9, and most of them were over 0.95 at both high and low heating rate; the activation energy of the volatile combustion phase was greater than that of the fixed carbon combustion stage, which were 43.0-97.7 and 29.6-41.6 kJ/mol respectively. In summary, biomass is suitable for the preparation of solid fuels through hydrothermal carbonization, and the fuel has good combustion characteristics. Combustion characteristics of woody biomass hydrochars are superior to that of herbaceous biomass hydrochars. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Combustion
Controlled terms:Activation analysis - Activation energy - Biomass - Carbonization - Chemical analysis - Coal - Coal combustion - Curing - Curve fitting - Energy utilization  - Enzyme kinetics - Flow of gases - Fuels - Heating - Heating rate - Ignition - Kinetics - Reaction kinetics - Thermochemistry - Thermogravimetric analysis
Uncontrolled terms:Carbon rich solid fuels - Combustion characteristics - Correlation coefficient - Hydrochar - Hydrothermal carbonization - Physicochemical property - Thermo-gravimetric - Thermochemical Conversion
Classification code:521.1  Fuel Combustion - 524  Solid Fuels - 525.3  Energy Utilization - 631.1.2  Gas Dynamics - 641.1  Thermodynamics - 641.2  Heat Transfer - 801  Chemistry - 801.4  Physical Chemistry - 802.2  Chemical Reactions - 921.6  Numerical Methods - 931  Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Time 1.80e+03s
DOI:10.11975/j.issn.1002-6819.2016.15.030

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 21>

Accession number:20163302706386
Title:Fe-modified biochar improving transformation of arsenic form in soil and inhibiting its absorption of plant
Authors:Dong, Shuangkuai (1); Xu, Wanli (2); Wu, Fufei (3); Yan, Cuixia (1); Li, Dianpeng (1); Jia, Hongtao (1) 
Author affiliation:(1) College of Pratacultural and Environmental Sciences, Xinjiang Agricultural University, Urumqi; 830052, China; (2) Institute of Soil and Fertilizer and Agricultural Sparing Water, Xinjiang Academy of Agricultural Science, Urumqi; 830091, China; (3) College of Civil and Hydraulic Engineering, Xinjiang Agricultural University, Urumqi; 830052, China 
Corresponding author:Jia, Hongtao(hongtaojia@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:204-212
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Arsenic has the chemical nature and toxicity to environment like heavy metals, and its toxicity will have a serious impact on human health, animal or plant. Only 0.1 g arsenic trioxide can cause human death, and long-term excessively drinking water or eating other foods containing arsenic will cause cancer in human organs. To reduce the effect of arsenic on human body, animal and plant, this paper uses unmodified biochar and biochar modified by FeCl<inf>3</inf>&middot;6H<inf>2</inf>O as test material; the former was prepared using cotton stalks whose carbonization temperature and time were 500&#8451; and 4 h, respectively, and the latter was prepared with the 20:1 mass ratio of cotton stalk biochar to FeCl<inf>3</inf>&middot;6H<inf>2</inf>O. A total of 35 groups of soil containing unmodified biochar or modified biochar or arsenic were designed, and the arsenic content of cabbage that was planted in pot was tested by atomic fluorescence spectrometer (PF6-1) to explore the influence of unmodified biochar and modified biochar on soil and plants absorbing arsenic. The results showed that: Unmodified biochar (10-40 g/kg) or modified biochar (10 g/kg) could promote the growth of cabbage, and the biomass of cabbage was the largest when the unmodified biochar was 20 g/kg and the modified biochar as 10 g/kg, which was 8.26 and 6.68 g per pot respectively. When the content of modified biochar was 10 g/kg, the biomass of cabbage was bigger than the control group and the treatment group with equivalent amount of unmodified biochar. The arsenic in soil was mainly residual form, and soluble arsenic increased by 0.22%-3.36% and 0.96%-3.70% respectively when the arsenic content was 10 and 20 mg/kg and the addition content of biochar was 10-40 g/kg. The soluble arsenic had no effect when the arsenic content was 10 mg/kg and the addition content of modified biochar was 10-40 g/kg, but the soluble arsenic decreased by 0.12%-0.58% when the arsenic content was 20 mg/kg. The content of soluble arsenic was increasing with soil arsenic content increasing when the content of arsenic in soil was 40 and 80 mg/kg; after adding biochar (10-40 g/kg), soluble arsenic increased by 0.21%-1.56% and 2.11%-8.94%, respectively, but the form of arsenic was mainly aluminum arsenic, and arsenic residues followed. The variation of arsenic mass fraction in edible parts and roots of cabbage in each treatment group was different after adding biochar (10-40 g/kg), but the mass fraction of arsenic in edible parts of cabbage significantly reduced from 18.28 to 2.66 mg/kg (P&lt;0.05), and the mass fraction of arsenic in roots of cabbage significantly reduced from 133.99 to 20.21 mg/kg (P&lt;0.05) after adding same amount of modified biochar. Comparing the modified biochar and unmodified biochar, it was found that modified biochar could reduce the content of soluble arsenic in soil and inhibit cabbage from absorbing arsenic. Therefore, this study may provide data support and theoretical basis for the application of modified biochar and unmodified biochar in soil restoration. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:42
Main heading:Chemical contamination
Controlled terms:Animals - Arsenic - Carbonization - Cotton - Heavy metals - Pollution - Potable water - Soils - Speed control - Toxicity
Uncontrolled terms:Arsenic trioxide - Atomic fluorescence spectrometers - Bio chars - Cabbage - Carbonization temperatures - Chemical nature - Soil restoration - Treatment group
Classification code:444  Water Resources - 461.7  Health Care - 483.1  Soils and Soil Mechanics - 531  Metallurgy and Metallography - 731.3  Specific Variables Control - 802.2  Chemical Reactions - 804  Chemical Products Generally - 821.4  Agricultural Products - 822.3  Food Products
Numerical data indexing:Mass 1.00e-04kg, Mass 6.68e-03kg, Percentage 1.20e-01% to 5.80e-01%, Percentage 2.10e-01% to 1.56e+00%, Percentage 2.11e+00% to 8.94e+00%, Percentage 2.20e-01% to 3.36e+00%, Percentage 9.60e-01% to 3.70e+00%, Time 1.44e+04s
DOI:10.11975/j.issn.1002-6819.2016.15.028

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 22>

Accession number:20163302706398
Title:Detection method of foreign fibers in cotton based on illumination of line-laser and LED
Authors:Zhang, Lin (1); Wei, Ping (1); Wu, Jianbo (1); Liu, Xiang (1); Su, Zhenwei (1, 2) 
Author affiliation:(1) School of Manufacturing Science and Engineering, Sichuan University, Chengdu; 610065, China; (2) Guangzhou Polytechnic College, Zhaoqing; 526100, China 
Corresponding author:Su, Zhenwei(zhenweisu99@hotmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:289-293
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is difficult for the existing machine vision systems to sort out white foreign fibers (contaminants) from cotton because their colors are the same or very close. The laser imaging method previously suggested by our research team can detect most of the white foreign fibers in cotton, but the reflect lights of laser from most of the colored foreign fibers, especially from the ones with deep colors are so weak that the colored foreign fibers cannot be distinguished from cotton. In this paper, a new method using a double-light illumination of light emitting diode (LED) and laser for imaging was presented, which could detect different colored foreign fibers, including most of the foreign fibers with white color and deep colors. In the experiment, lint cotton and 20 kinds of typical foreign fibers with deep colors, light colors and white color were collected from a textile plant, and then the foreign fibers were randomly distributed on the cotton surface and driven by a conveyor. Using the line-laser at wavelength of 658 nm, exposure time of 106 &mu;s and aperture of 2.8 C that were previously suggested by our team, 310 frames of the sample images were obtained by a high-speed color line-scan camera under the double-light illumination formed by 2 LED arrays with adjustable luminance and a line-laser with adjustable power. Then, the quantized differences of foreign fibers and cotton background in each frame of the image were calculated by their average pixel values in R channel of RGB (red, green and blue) color space and their average saturation values in S channel of HIS (hue, saturation and intensity) color space separately. Based on the experiment, it was found that in the R channel or S channel, with the increase of the line-laser power or the LED luminance, quantized differences of the foreign fibers and cotton were enlarged, and after the differences reached the maximum value, the curve gradually decreased from the top. Thus, by the significant difference of the targets and background at the 2 curves' tops respectively, the white foreign fibers and other colored fibers could be easily detected from cotton in the images under the double-light imaging condition. Combining the 2 curves together, an optimized imaging method was obtained, by which the images were captured by a colored line scan camera L301KC at the exposure time of 106 &mu;s and aperture of 2.8 C under the double-light illumination with the LED luminance of 3326lx and the line-laser at wavelength of 658 nm and power of 7.01 mW. Finally, in a comparing experiment, 840 frames of images of 20 kinds of typical foreign fibers with different colors on the cotton surface were taken by the double-light imaging method, LED light imaging method and line-laser imaging method respectively. Then, using the Sobel edge detecting algorithm, the whole successful detecting rate was 86.7% for the double-light imaging method; using the fixed threshold binary algorithm, the successful detecting rates of the white foreign fibers and the other colored fibers could reach up to 84.1% and 93.9% respectively, which were much higher than that of the images from the illumination of individual light source of LED or laser. Next research will focus on the development of the double-light imaging method from the laboratory stage to an on-line stage and the design of faster and more efficient image processing algorithms. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:16
Main heading:Light emitting diodes
Controlled terms:Cameras - Color - Computer vision - Cotton - Curve fitting - Edge detection - Fibers - Image processing - Lasers - Light sources  - Luminance
Uncontrolled terms:Comparing experiments - Edge detecting algorithm - Foreign fiber - Image processing algorithm - Light illumination - Machine vision systems - Randomly distributed - Red , green and blues
Classification code:714.2  Semiconductor Devices and Integrated Circuits - 741.1  Light/Optics - 741.2  Vision - 742.2  Photographic Equipment - 744.1  Lasers, General - 821.4  Agricultural Products - 921.6  Numerical Methods
Numerical data indexing:Illuminance 3.33e+03lx, Percentage 8.41e+01%, Percentage 8.67e+01%, Percentage 9.39e+01%, Power 7.01e-03W, Size 6.58e-07m, Time 1.06e-04s
DOI:10.11975/j.issn.1002-6819.2016.15.040

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 23>

Accession number:20163302706368
Title:Experiment and analysis of effects of rotational speed on performance of pump as turbine
Authors:Wang, Tao (1, 2); Kong, Fanyu (2); Chen, Kai (2); Duan, Xiaohui (2); Gou, Qiuqin (3) 
Author affiliation:(1) School of Energy and Power Engineering, Xihua University, Chengdu; 610039, China; (2) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang; 212013, China; (3) Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu; 610039, China 
Corresponding author:Kong, Fanyu(kongm@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:67-74
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A reverse running centrifugal pump is one of the most convenient choices with lower cost in micro-hydropower development and industrial pressure energy recovery. One of the main limitations in utilizing pump as turbine(PAT) technique is that the PAT usually runs at part load for several months in a year due to insufficient water availability for the power production. Variable speed operation offers an effective solution to this problem. Pump manufactures normally do not provide performance curves of pump running in turbine mode, especially when working at variable speed condition. In addition, performance test may often be required to be carried out in order to accurately obtain the operation parameters before high power PAT working in industrial pressure energy recovery. Due to the limitation of the laboratory power capacity, the performance of rated rotational speed condition is often estimated through decreasing rotational speed in the test. It is difficult to accurately obtain the performance parameters of the rated condition. Therefore, experimental research at different rotational speed is useful to understand the correlations between PAT's performance parameters and rotational speed. In the present research, an open PAT test rig was set up. An electric eddy current dynamometer (EECD) was installed in the rig to measure and consume energy generated by PAT. And an automatic control system was used in the test to regulate rotational speed of PAT. The rotational speed of PAT was varied by adjusting the rotational speed of EECD. To study the effects of rotational speed on the performance, the operation of PAT was simulated by using computational fluid dynamics (CFD) technique at different speed ranging from 900 to 2100 r/min with a step of 300 r/min. Through the comparison of performance curves obtained by experiment, we could find that the trend at different rotational speed was similar. The head and shaft power curves both increased with the increase of flow rate. And the PAT efficiency first increased to the maximum and then decreased with the increase of flow rate. Rotational speed had an obvious effect on the performance of PAT. The results showed that PAT's BEP(best efficiency point) shifted towards higher discharge and its high efficiency range became wider with the increase of rotational speed. The comparison of the results obtained by CFD and by using proportional law theory calculation showed that the performance parameters of BEPs at different rotational speed were almost consistent. However, CFD could not objectively reflect the effects of variable speed on efficiency completely. The comparison of the results obtained by experiment and by theory calculation showed that the performance parameters of BEPs at different rotational speed had a certain degree of deviation. And the flow rate deviation was the minimum, followed by the head deviation and the shaft power deviation. Comparing the theory calculation values, the deviations of flow rate, head and shaft power obtained by experiments were about 10%, 12.17% and 15.4%, respectively, when the rotational speed declined from 1 500 to 900 r/min. At the same time, the rotating speed had also obvious influence on the PAT's efficiency. The maximum efficiencies were reported as 65.4%, 67.86%, 69.83% and 70.25% at 900, 1 200, 1 500 and 1 800 r/min, respectively. Through theoretical analysis, decreasing speed had a negative influence on the volumetric efficiency and mechanical efficiency, while increasing speed had a nonlinear positive influence. At part load operating conditions, the more the speed was below the rated speed, the more the efficiency declined. And variable speed operation was more meaningful. While the hydraulic resource and strength both met the requirements of operating conditions, the rotational speed should be equal to or slightly higher than the rated speed, which could effectively use the energy. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Speed
Controlled terms:Automation - Centrifugal pumps - Computation theory - Computational fluid dynamics - Computer simulation - Flow rate - Hydraulic motors - Pumps - Rating - Turbines
Uncontrolled terms:Comparison of performance - Economic operations - Eddy current dynamometer - Experiment and analysis - Performance experiment - Rotational speed - Variable speed conditions - Variable speed operations
Classification code:618.2  Pumps - 631  Fluid Flow - 632.2  Hydraulic Equipment and Machinery - 721.1  Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.5  Computer Applications - 731  Automatic Control Principles and Applications
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.22e+01%, Percentage 1.54e+01%, Percentage 6.54e+01%, Percentage 6.79e+01%, Percentage 6.98e+01%, Percentage 7.02e+01%, Rotational_Speed 1.50e+03RPM to 9.00e+02RPM, Rotational_Speed 1.80e+03RPM, Rotational_Speed 3.00e+02RPM, Rotational_Speed 9.00e+02RPM to 2.10e+03RPM
DOI:10.11975/j.issn.1002-6819.2016.15.010

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 24>

Accession number:20163302706399
Title:Experiment and discrete element model of rice seed based on 3D laser scanning
Authors:Liu, Cailing (1); Wang, Yali (1); Song, Jiannong (1); Li, Yanni (1); Ma, Tuo (1) 
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China 
Corresponding author:Song, Jiannong(songjn@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:294-300
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the process of discrete element numerical calculation, the establishment of the particle model is an important factor to affect the accuracy of the simulation. It is necessary to establish the 3-D models of irregular grains for discrete element method whose morphology is approximate to the real grain to analyze and simulate the main working process like precision seeding and precision selecting and classifying seeds. At present, an irregular particle with complex contours is simplified into the regular shape to model, which can lead to reduction of the simulation accuracy. In order to improve the accuracy of the dynamic simulation of the irregular particles, a method of modeling 3-D DEM models was proposed for irregular shape particles like rice grain based on 3-D laser scanning. Five hundreds of Kongyu 131 (rice cultivar) rice seeds were chosen randomly and scanned using CF-30 automatic high precision 3-D scanner. The size distribution of length, width and thickness is in accordance with the normal distribution and the average length, average width and average thickness of the three-dimensional measurement were 7.0 mm, 3.5 mm and 2.4 mm, respectively. The rice seed with the average three-dimensional sizes was scanned and the polygonal contour model and space coordinate information were obtained by the process of treating color, noise removal, point cloud registration, point cloud triangulation, consolidation and model modification using the reverse engineering software Geomagic Studio. The polygonal contour model was imported into SolidWorks and the 3-D DEM model with complex contour of the rice seed based on 3D laser scanning was created by inverse modeling. The 3-D DEM model of the rice seed based on 3D laser scanning was filled by 87 balls particles based on the theory of polymer particles, which was named as Model1. The 3-D DEM model of the rice seed with the same three-dimensional sizes as Model1 was processed usually as regular ellipsoid, which was named as Model 2. In order to test the simulation accuracy for discrete element method of the modeling method of irregular particle based on 3D laser scanning, the simulation prediction of repose angle for Model 1 and Model 2 was done respectively using the discrete element method software EDEM. The repose angle of the Model 1 and the Model 2 were 29.77 &deg; and 27.08&deg;, respectively. And the repose angle of the actual rice seeds was measured under the same condition as the simulated experiment condition for comparative analysis. The experimental result of the repose angle was 29.70&deg;. And the measurement errors between the simulation results by two modelling methods and the actual experiment value about repose angle were 0.24% and 8.83%, respectively. The repose angle obtained by Model 1 based on 3-D laser scanning was closer to not only the experimental measured value but also accumulation form, and there was a big error between that by Model 2 based on the usual treatment as regular ellipsoid and the experimental result, which showed that the modeling method of irregular particle for discrete element based on 3-D laser scanning was validated and available. This paper provides a new means to improve simulation precision of irregular particles for discrete element method. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Scanning
Controlled terms:Computer software - Filled polymers - Grain (agricultural product) - Inverse problems - Laser applications - Laser theory - Lasers - Normal distribution - Reverse engineering - Software testing  - Surface analysis - Three dimensional computer graphics
Uncontrolled terms:Discrete element modeling - Numerical calculation - Point cloud registration - Point cloudy - Repose angles - Rice seed - Simulation prediction - Three-dimensional measurements
Classification code:723  Computer Software, Data Handling and Applications - 723.5  Computer Applications - 744.1  Lasers, General - 744.9  Laser Applications - 821.4  Agricultural Products - 922.1  Probability Theory - 951  Materials Science
Numerical data indexing:Percentage 2.40e-01%, Percentage 8.83e+00%, Size 2.40e-03m, Size 3.50e-03m, Size 7.00e-03m
DOI:10.11975/j.issn.1002-6819.2016.15.041

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 25>

Accession number:20163302706364
Title:Simulation of 3D wind velocity inflowing into wind turbine based on improved VonKarman model
Authors:Yang, Congxin (1, 2); Gao, Zhiteng (1); Zhang, Xuyao (1) 
Author affiliation:(1) School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou; 730050, China; (2) Key Laboratory of Fluid Machinery and Systems, Lanzhou; Gansu Province; 730050, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:39-46
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Currently, as an effective technique to face the energy crisis, large-scale wind turbines in MW level is more and more widely used in the field of environment protection and green energy industry. In boundary layer wind field, random wind load can bring more obvious aerodynamic load fluctuation to long blades and high tower, which affects the structural stability of wind turbines. An accurate random wind speed model plays a significant role in the aerodynamic load calculations of wind turbines in the atmospheric boundary layer. Random wind speed can be decomposed into averaging wind speed and fluctuating wind speed. The averaging wind speed can be described by wind shear effect, and the fluctuating wind speed can be described by turbulence spectra. In the runtime environment of wind turbines, it's proper to use specific turbulence spectra to describe the fluctuating wind speed of inflow on the inlet because the entrance region of wind farm is the equal of a flat field. Compared with static buildings, the dynamic turbine rotor causes great disturbances to the wind speed. So the hybrid numerical simulation to combine the random wind speed generated by specific turbulence spectra on the inlet with turbulence models is more appropriate to the aerodynamic load calculations. In this paper, we verified the accuracy of random wind speed generation methods on the inlet of wind turbines. IEC61400-1 and many research papers recommend to use exponential law to describe the wind shear effect. The improved Von Karman spectrum corrected the flaws of Von Karman spectrum below about 150 m, which is more appropriate to wind farms. Based on the exponential law, 3D improved Von Karman spectrum and cross-spectrum model. We used the harmony superposition method and auto-regressive moving-average method to generate fluctuating wind speed of a 33 kW horizontal axis wind turbine. The hub height of this wind turbine was 15.4 m, and the rated wind speed was 11 m/s. The terrain roughness length was 0.03 m and the wind shear index was 0.2. The time step was 0.1 s and the upper rate limit was 2&pi; rad/s. The length of the simulation was 100 s. The inlet was a rectangular area with 30 m &times; 30 m, and the grid step was 2 m. As a contrast, in this paper, we used the PSCAD to generate fluctuating wind speed with the same parameter. We compared these three methods, power spectrum, self-correlation and cross-correlation. The results showed that the power spectrum which was produced by HSM fit well with target power spectrum. The self-correlation of these three methods decreased as time increased, and the self-correlation of ARMA and PSCAD was better than HSM. The cross-correlation from the HSM method decreased as distance increased, which fit well with the measured results. Last, in this paper, we compared the turbulence intensity and got the three-dimensional distributions of velocity on the inlet. The turbulence intensity decreased as height increased, the difference value of turbulence intensity in the along-wind, crosswind, vertical wind was 8.96%, 6.98%, and 4.91%, respectively. This difference value would be more obvious on the large-scale wind turbines. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Wind
Controlled terms:Aerodynamic loads - Aerodynamic stability - Aerodynamics - Atmospheric boundary layer - Atmospheric thermodynamics - Boundary layers - Electric utilities - Energy policy - Models - Plasma diagnostics  - Power spectrum - Shear flow - Signal encoding - Speed - Stability - Turbine components - Turbomachine blades - Turbulence models - Velocity - Wind power  - Wind turbines
Uncontrolled terms:Autoregressive moving average - Environment protection - Fluctuating wind - Fluctuating wind speed - Harmony superposition method - Horizontal axis wind turbines - Large scale wind turbines - Structural stabilities
Classification code:443.1  Atmospheric Properties - 525.6  Energy Policy - 615.8  Wind Power (Before 1993, use code 611 ) - 617  Turbines and Steam Turbines - 631.1  Fluid Flow, General - 651  Aerodynamics - 651.1  Aerodynamics, General - 716.1  Information Theory and Signal Processing - 932.3  Plasma Physics
Numerical data indexing:Percentage 4.91e+00%, Percentage 6.98e+00%, Percentage 8.96e+00%, Power 3.30e+04W, Size 1.50e+02m, Size 1.54e+01m, Size 2.00e+00m, Size 3.00e+01m, Size 3.00e-02m, Time 1.00e+02s, Time 1.00e-01s, Velocity 1.10e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.15.006

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 26>

Accession number:20163302706389
Title:Monitoring soil moisture at different subsidence areas of mining in western windy and sandy region with neutron instrument
Authors:Tai, Xiaoli (1); Hu, Zhenqi (1); Chen, Chao (1) 
Author affiliation:(1) Institute of Land Reclamation and Ecological Restoration, China University of Mining and Technology, Bingjing; 100083, China 
Corresponding author:Hu, Zhenqi(huzq@cumtb.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:225-231
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to research the influence of mining subsidence on soil water content and the variation characteristics of soil water content in windy and sandy region, the authors selected a working face of Da Liuta mining district as the research object, which has the similar characteristics with other mining faces, such as working thickness and mining progress. We divided the subsidence area into pelvic floor area and marginal zone. The pelvic floor area has dynamic fractures which can be quickly closed in the cycle of 18 d. The marginal zone has marginal fractions and additional slopes. And when mining is finished, the marginal fractures are still existing. We used neutron probe method to monitor soil moisture of pelvic floor area, marginal zone and unexploited area. The monitoring depth was 10-200 cm. The monitoring lasted for 2 years. By comparing 2 subsidence areas' soil water content with unexploited area, we could find the impact law of mining and give feasible advice for land reclamation and ecological rehabilitation in western windy and sandy region. The result showed that: 1) Before exploitation, the study area's soil moisture content of 10-200 cm depth had obvious layered characteristic, and the depth could be divided into two layers based on the differences of soil water content variation. In 10-60 cm depth, water content increased linearly, and it was then stable and decreased slightly in 60-200 cm depth. 2) Mining subsidence could exert influence on soil water content of both the pelvic floor area and the marginal zone. And the influence of mining subsidence on soil water content had obvious leveling and zoning characteristics. Pelvic floor area's water content decreased in 10-120 cm and increased in 140-180 cm. Meantime, soil water content decreased in marginal zone. In general, the mining subsidence's influence on marginal zone was greater than the pelvic floor area. 3) After mining, the soil water contents of pelvic floor area presented the phenomenon of recovery. Just one year after mining, the water content could be recovered to the one before, and one and a half years or two years after mining, the water content showed the characteristic of being higher than unexploited area. The recovery effect of marginal area's soil water content was not so obvious. The soil water content at 140 cm depth could recover to the level of unexploited area in one and a half years after mining, but the soil water content of 10-140 cm depth did not eliminate the impact of mining after 2 years. Therefore, while performing land reclamation and ecological rehabilitation on the west windy and sandy coal mining subsidence land, we should implement subarea management. We can make full use of self-reliant ability of pelvic floor area's soil water content. At the same time, we should adopt artificial restoration measures to restore soil water content of marginal area in time in order to meet the water needs of plant growth. In this way, we can rely on the power of nature as far as possible and implement management purposefully. Not only can it reduce the possibility of secondary disturbance brought by the artificial restoration measures, but it can reduce the cost of ecological restoration. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Water content
Controlled terms:Coal reclamation - Cutting machines (mining) - Ecology - Floors - Fracture - Land reclamation - Land use - Mining - Moisture - Moisture control  - Monitoring - Neutrons - Probes - Recovery - Restoration - Soil moisture - Soils - Subsidence
Uncontrolled terms:Coal mining subsidences - Ecological rehabilitation - Ecological restoration - Neutron probes - Restoration measures - Sandy region - Subsidence areas - Variation characteristics
Classification code:402  Buildings and Towers - 403  Urban and Regional Planning and Development - 442.2  Land Reclamation - 454.3  Ecology and Ecosystems - 483.1  Soils and Soil Mechanics - 502.1  Mine and Quarry Operations - 502.2  Mine and Quarry Equipment - 524  Solid Fuels - 731.3  Specific Variables Control - 951  Materials Science
Numerical data indexing:Age 2.00e+00yr, Size 1.00e-01m to 1.20e+00m, Size 1.00e-01m to 1.40e+00m, Size 1.00e-01m to 2.00e+00m, Size 1.00e-01m to 6.00e-01m, Size 1.40e+00m, Size 1.40e+00m to 1.80e+00m, Size 6.00e-01m to 2.00e+00m
DOI:10.11975/j.issn.1002-6819.2016.15.031

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 27>

Accession number:20163302706374
Title:Optimal design and experiment of fertilizer EC regulation based on subsection control algorithm of fuzzy and PI
Authors:Wang, Haihua (1, 2); Fu, Qiang (1); Meng, Fanjia (1); Mei, Shuli (2); Wang, Junheng (1); Li, Li (1) 
Author affiliation:(1) Key Laboratory on Modern Precision Agriculture System Integration Research of Ministry of Education, China Agricultural University, Beijing; 100083, China; (2) College of Electrical and Information, China Agricultural University, Beijing; 100083, China 
Corresponding author:Li, Li(lily@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:110-116
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Precise control of EC for fertilizer solution is one of the key technologies to realize smart irrigation in the production of protected vegetable. Serious lag and instability in EC detection will happen during the mixing of fertilizer and water due to differences in mother liquor concentration, fertilizer suction method and irrigation flow etc. To solve this problem, a new EC sensor was designed to measure the EC value of fertilizer solution indirectly by measuring the frequency based on different EC values leading to different equivalent resistances, and the smart irrigation system was developed as microcontroller (MSP430) was the master controller. Meanwhile, a subsection control strategy was introduced to regulate and control the EC value of fertilizer solution, and the opening or closing of electromagnetic valve for the suction of fertilizer solution was controlled by outputting corresponding duty cycle. When the difference between the target EC value and the measured value was large, PI control was adopted to narrow the gap as fast as possible. In this study, the threshold is defined as 0.2 mS/cm according to practical knowledge, therefore, fuzzy control with good robustness and high adaptability was adopted when the difference was smaller than 0.2 mS/cm. In fuzzy control stage, triangle function and centroid method were selected as membership function and defuzzification calculation with 63 rules and the output language variable value was divided into 13 levels. A compound venturi was designed as fertilizer solution suction device, with the diameter of inlet and outlet pipes was both 40 mm, and a closed-container (10 cm&times;10 cm&times;6 cm) was installed at the throat part to connect the inlet and outlet pipes, and 7 suction interface were located at the bottom of the container to link with the electromagnetic valves. The main pipe of the irrigation system was controlled by 24VDC electromagnetic valve and the drippers of the branch pipes were inserted into the substrate near plant roots. The filter was installed between inlet water and the irrigation system to avoid blocking venturi and drippers. An experiment including 4 different target EC values and 4 different suction pipelines was carried out to test the effect of the designed control system. The results showed that the frequency measured by our EC sensor had a significant linear correlation with the measured EC value with R²is 0.999 5. In the case of subsection control, when the target EC value was 2 mS/cm, the steady response time was 122 s and maximum overshoot is 0.34 mS/cm when 4 channels were used for fertilizer solution suction, which performed much better than only PI control with steady response time 180 s and maximum overshoot up to 0.62 mS/cm. In addition, the higher the target EC value set, the more accurate the steady EC value was, however, the steady response time became longer and overshoot was more serious. The subsection control strategy used in this study can effectively overcome excessive overshoot, also the time for mixing fertilizer solution and the measured EC value can both meet the requirements for the practical production of protected vegetable. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Controllers
Controlled terms:Algorithms - Containers - Fertilizers - Fuzzy control - Greenhouses - Irrigation - Membership functions - Mixing - Plant shutdowns - Response time (computer systems)  - Sensors - Three term control systems - Two term control systems - Vegetables
Uncontrolled terms:Algorithm of fuzzy - Electromagnetic valves - Equivalent resistance - Integration of water and fertilizers - Linear correlation - PI control - Practical production - Sub-section control
Classification code:731  Automatic Control Principles and Applications - 731.1  Control Systems - 732.1  Control Equipment - 802.3  Chemical Operations - 804  Chemical Products Generally - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921  Mathematics
Numerical data indexing:Electrical_Conductivity 2.00e-01S/m, Electrical_Conductivity 2.00e-02S/m, Electrical_Conductivity 3.40e-02S/m, Electrical_Conductivity 6.20e-02S/m, Size 4.00e-02m, Time 1.22e+02s, Time 1.80e+02s
DOI:10.11975/j.issn.1002-6819.2016.15.016

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 28>

Accession number:20163302706372
Title:Influence of pressure and pore diameter on droplet parameters of hollow cone nozzle in pipeline spray
Authors:Dai, Qiufang (1, 2, 4); Hong, Tiansheng (1, 2, 3); Song, Shuran (1, 2, 4); Li, Zhen (1, 2, 4); Chen, Jianze (3) 
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou; 510642, China; (2) Division of Citrus Machinery, China Agriculture Research System, Guangzhou; 510642, China; (3) College of Engineering, South China Agricultural University, Guangzhou; 510642, China; (4) College of Electronic Engineering, South China Agricultural University, Guangzhou; 510642, China 
Corresponding author:Hong, Tiansheng(tshong@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:97-103
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Mountainous orchards are the majority type of orchards in southern China. This type of orchards usually adapts low plant height and high-density cultivation mode, which makes it difficult for mobile spray machines to get into the orchards. Lever-operated knapsack sprayers and stretcher mounted sprayer with long flexible pipe are still in use by many orchardists to finish the spray work which makes the task laborious and inefficient. Pipeline spraying technology with no need for moving fulfills the management request of mountainous orchards, and also, it has the characteristics of saving time and vigor. Droplet parameters and droplet spectrum can reflect the droplets size, distribution and uniformity, and meanwhile are the key measures of spray effect. Spray pressure and nozzle pore diameter are the main factors affecting droplet parameters pipeline constant pressure spray facilities. In order to access the influence of spray pressure and nozzle pore diameter on droplet parameters of hollow cone nozzle for pipeline constant pressure spray facilities in orchards, we studied five important aspects of spray performance combined with test platform and laser particle analyzer through measuring droplets scattering spectra of hollow cone nozzle at three types of pore diameter and eight levels of pressure. From such study, we wanted to determine variations of droplet parameters with different pressure and nozzle pore diameter, draw droplet spectrum curves of various working conditions, analyze droplets diameter, distribution and uniformity, and build droplet parameters models based on pressure and nozzle pore diameter. The results showed that the higher the pressure was, and the smaller the pore diameter of the nozzle was, the tinier and the more uniform the droplets would be. Second, at pressure of 0.70-1.40 MPa, data fitting error of three types of nozzles were less than 0.012, which fulfilled the request of experiment. There were not droplets with diameter more than 200 &mu;m. Droplets with diameter 100-200 &mu;m could be ignored because the percentage of them was less than 0.3%. The diameters of the majority droplets(&gt; 99.728%) were less than 100 &mu;m. The percentage of droplets with diameter less than 50 &mu;m was 86.786%-98.706%, and the percentage of droplets with diameter less than 40 &mu;m was 79.659%-93.374%. There were mainly droplets with diameters 20-50 &mu;m in droplet spectrum curves, and droplet spectrum peak appeared at 30 &mu;m. Volume median diameter(VMD) of droplets was 30.610-32.317 &mu;m, and diffusion ratio(DR) was 0.893-0.916. Droplets were all tiny and uniform, and the majority type was aerosol. Third, at pressure of 0.70-1.40 MPa, VMD of droplets was 30.610-31.632 &mu;m, and DR was 0.901-0.916. Droplets were tinier and more uniform, and the type was aerosol. When the pressure was more than 0.80 MPa, spray effect were better. The relationships between VMD and DR of droplets, and pressure could both be described by quadratic polynomial equations (R²&gt;0.968), and meanwhile, VMD and DR of droplets influenced by pressure and pore diameter could both meet the binary linear equations(R²=0.928, 0.937). The results have verified the importance of studying pipeline constant pressure spray system, and meanwhile provided basis for selecting nozzle, optimizing pipeline constant pressure spray system, setting spray pressure and optimizing spray effect. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Spray nozzles
Controlled terms:Aerosols - Drops - Farms - Models - Nozzles - Orchards - Pipelines - Polynomials - Pressure effects - Spraying
Uncontrolled terms:Different pressures - Droplet spectrums - Laser particle analyzer - Pore diameters - Quadratic polynomial - Scattering spectra - Spray pressure - Spraying technology
Classification code:619.1  Pipe, Piping and Pipelines - 631.1  Fluid Flow, General - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.3  Agricultural Methods - 921.1  Algebra - 931.1  Mechanics
Numerical data indexing:Percentage 3.00e-01%, Percentage 7.97e+01% to 9.34e+01%, Percentage 8.68e+01% to 9.87e+01%, Percentage 9.97e+01%, Pressure 7.00e+05Pa to 1.40e+06Pa, Pressure 8.00e+05Pa, Size 1.00e-04m, Size 1.00e-04m to 2.00e-04m, Size 2.00e-04m, Size 2.00e-05m to 5.00e-05m, Size 3.00e-05m, Size 3.06e-05m to 3.16e-05m, Size 3.06e-05m to 3.23e-05m, Size 4.00e-05m, Size 5.00e-05m
DOI:10.11975/j.issn.1002-6819.2016.15.014

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 29>

Accession number:20163302706365
Title:Variation characteristics of near-field spray cone angle of diesel engine based on ultra-high speed imaging
Authors:Wang, Qian (1); Sun, Wei (1); He, Zhixia (1); Fang, Mingcheng (1) 
Author affiliation:(1) School of Energy and Power Engineering, Jiangsu University, Zhenjiang; 212013, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:47-53
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The near-field spray cone angle is one of the significant indicators that evaluate the primary atomization quality in the near- field area, the dynamic characteristics of which has a remarkable impact on the subsequent secondary atomization and combustion performance. However, the variation of near-field spray cone angle in the whole spray process is rarely studied. In order to make up for this work and provide a new reference for improving atomization performance, the characteristics of near-field spray cone angle of diesel jets 4 mm away from the nozzle tip under different injection pressures, back pressures and nozzle diameters were experimentally investigated by photography technique with the help of backlighting. An ultra-high speed digital camera of the Photron Fastcam SAZ type was employed with the maximum shooting frequency of 210000 fps (frames per second), and a fixed resolution of 384&times;160 pixels and a pixel size of 20 &mu;m &times; 20 &mu;m were obtained; and the exposure time of 250 ns was selected, which greatly reduced the trailing phenomenon. In addition, the high-resolution long distance microscope with the working distance ranging from 56 to 140 cm was employed. And a high pressure diesel fuel pump driven by a converter motor provided a controllable fuel pressure up to 160 MPa to the common rail. The injection pulse width was set as 1500 &mu;s in the experiment and 3 different injection pressures were chosen, namely, 40, 60 and 80 MPa. Besides, the nozzle diameters were 0.12, 0.16 and 0.18 mm respectively and 4 back pressures were selected (0.1, 2, 3 and 4 MPa). To thoroughly investigate the variation characteristics of near-field spray cone angle, the whole spray process was divided into 3 stages, i.e., the beginning stage, the steady stage and the ending stage based on the needle valve lift curve while the injection pressure was 80 MPa. The results indicated that near-field spray cone angle presented a three-stage development, and there were 2 peaks (the beginning-period peak and the ending-period peak) and a period of stable fluctuation. During the beginning stage of injection, the beginning-period peak appeared earlier with the higher injection pressure, its value became higher, and simultaneously the duration of this stage was shorter, indicating the better starting-injection performance. However, the back pressure had a little influence on the near-field spray cone angle, and the development profiles of near-field spray cone angle under various back pressures were nearly superimposed during a period of time before and after the peak when the internal flow of the nozzle dominated the spray process; and then the distinction among different curves was gradually evident as the aerodynamic force played a major role in the spray development. Furthermore, the starting-injection performance was not affected by the back pressure. During the ending stage of injection, with the increase of the injection pressure and back pressure, the ending-period peak appeared later, however, the value of the peak was larger. Meanwhile, the fuel injection duration was longer as the injection pressure and back pressure increased when the injection pulse width was set as 1500 &mu;s. During the steady stage of injection, a rise appeared in the figure for near-field spray cone angle with the increase of the back pressure. Nevertheless, the spray cone angle showed a decreasing trend with the increase of the nozzle diameter, and as for this phenomenon, there were 2 reasons to explain, one was the hydraulic flipping regime led to complete detachment of liquid from the hole wall, and the other was the small aperture spray was susceptible to the influence of small scale air entrainment and had the large surface curvature which would result in the bigger cone angle value for the small aperture spray. Taking the fact into consideration that the aerodynamic force governed the spray process in steady stage, the latter explanation was supposed to be the more reasonable one. Consequently, the injection pressure has more significant influence on the near-field spray than the back pressure, and the nozzle hole with smaller diameter can obtain the better atomization quality. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Spray nozzles
Controlled terms:Aerodynamics - Air entrainment - Atomization - Diesel engines - Diesel fuels - Engines - Fighter aircraft - Fuel oils - Fuels - Ignition  - Injection (oil wells) - Nozzles - Pixels - Pressure
Uncontrolled terms:Atomization performance - Combustion performance - Dynamic characteristics - Nozzle diameter - Spray cone angle - Three stage development - Ultra high speed imaging - Variation characteristics
Classification code:511.1  Oil Field Production Operations - 521.1  Fuel Combustion - 523  Liquid Fuels - 612.2  Diesel Engines - 631.1  Fluid Flow, General - 651.1  Aerodynamics, General - 652.1.2  Military Aircraft - 802.3  Chemical Operations - 931.1  Mechanics
Numerical data indexing:Pressure 4.00e+06Pa, Pressure 8.00e+07Pa, Size 1.80e-04m, Size 2.00e-05m, Size 4.00e-03m, Size 5.60e-01m to 1.40e+00m, Time 1.50e-03s, Time 2.50e-07s
DOI:10.11975/j.issn.1002-6819.2016.15.007

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 30>

Accession number:20163302706366
Title:Lubricant adding with wheat leaf surface wax improving friction performance of steel/copper friction pair
Authors:Shi, Qiuyu (1); Xia, Yanqiu (1); Feng, Xin (1) 
Author affiliation:(1) School of Energy and Mechanical Engineering, North China Electric Power University, Beijing; 102206, China 
Corresponding author:Xia, Yanqiu(xiayq@ncepu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:54-59
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Environmental friendly and biodegradable lubricant has been a significant research focus for the purpose of reducing environmental pollution, and some plant constituents have been utilized as lubrication additives. Plant leaves are known to be covered by thin wax layer, which was called plant leaf-surface wax or plant epicuticular wax. Plant leaf-surface wax is a mixture of organic material including alkanes, alcohols, esters, and acids, which have proved to be good lubrication additives. Based on this, wheat leaves were selected as research object. The tribological properties of wheat leaf-surface wax as additives were evaluated on MFT-R4000 reciprocating friction and wear tester. The tests were conducted on steel-copper friction pair, and the friction coefficient was recorded automatically by a computer connected to the MFT-R4000 tester, the wear volume of worn surfaces was measured by a surface profilometer. The morphologies and element constitution of worn surfaces were observed and examined using scanning electron microscope (SEM) and energy-dispersive X-ray spectroscopy (EDX), respectively. The results showed that poly-&alpha;-olefin (PAO) containing wheat leaf-surface wax had excellent tribological properties. In the case of friction coefficient, PAO containing wheat leaf-surface wax as additives showed lower and more stable friction coefficient on steel-copper friction pair than other additives. Its average friction coefficient was reduced by 25% compared with the pure PAO, and its friction reduction property was close to MoDTC. Compared with PAO or PAO containing MoDTC, glycerin, and stearic acid, the wear volume of wheat leaf-surface wax was almost reduced by 70%. Obviously, wheat leaf-surface wax possessed superior anti-wear performance compared with MoDTC and stearic acid, and was similar to glycerol. The SEM results showed that PAO with wheat leaf-surface wax had fewer scratches, shallower grinding crack, and smaller edge roughness compared with pure PAO. The worn surface of PAO mixed with stearic acid and glycerol was similar to that of PAO with wheat leaf-surface wax, but deeper and clearer. Gas chromatography-mass spectrometry (GC-MS) method was used to analyze wheat leaf-surface wax constitution, and the results showed that wheat leaf-surface wax was mainly composed by fatty alcohol and fatty acid. As such, fatty alcohol content in wheat leaf-surface wax was about 54.3%, the carbon chain length mainly ranged between C20-C30 and concentrated on C26 and C27. The majority of alcohols were straight chain fatty alcohol, and some had annular structure. Meanwhile, wheat leaf-surface wax also included alkane and the corresponding content was about 19%, and the carbon chain length ranged between C21-C30. Fatty acid of the wheat leaf-surface wax was about 2.6% in content. The test results also showed most carbon chains owned odd number of carbon atoms. The alcohols, acids and other natural ingredients mixture in wheat leaf-surface wax can form a protective adsorption film on the worn surface. The esterification reaction also performed on the worn surface. The protective adsorption film was the reason for the improved friction reduction and anti-wear properties of lubricant on steel-copper friction pair. This research provides a reference to the study of extracting excellent green biodegradable additive from plants, and also has a great significance for economically utilization of plant leaves. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Surface reactions
Controlled terms:Additives - Alcohols - Chain length - Chains - Chromatography - Copper - Energy dispersive spectroscopy - Esterification - Esters - Fatty acids  - Friction - Gas chromatography - Glycerol - Lubricants - Lubrication - Mass spectrometry - Mixtures - Paraffins - Plants (botany) - Scanning electron microscopy  - Stearic acid - Tribology - Wear of materials - Wear resistance - X ray spectroscopy
Uncontrolled terms:Biodegradable - Biodegradable lubricants - Energy dispersive X ray spectroscopy - Friction pair - Friction reduction properties - Gas chromatography-mass spectrometry methods - Leaf surfaces - Plant
Classification code:544.1  Copper - 602.1  Mechanical Drives - 607.1  Lubricants - 607.2  Lubrication - 801  Chemistry - 801.4  Physical Chemistry - 802.2  Chemical Reactions - 802.3  Chemical Operations - 803  Chemical Agents and Basic Industrial Chemicals - 804.1  Organic Compounds - 931  Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 1.90e+01%, Percentage 2.50e+01%, Percentage 2.60e+00%, Percentage 5.43e+01%, Percentage 7.00e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.008

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 31>

Accession number:20163302706367
Title:Determination of special impeller diameter for pump as turbine and its effects on turbine performance
Authors:Wang, Tao (1, 2); Kong, Fanyu (1); Yang, Sunsheng (1); Chen, Kai (1); Gou, Qiuqin (3) 
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang; 212013, China; (2) School of Energy and Power Engineering, Xihua University, Chengdu; 610039, China; (3) Key Laboratory of Fluid and Power Machinery, Ministry of Education, Xihua University, Chengdu; 610039, China 
Corresponding author:Kong, Fanyu(kongm@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:60-66
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A reverse running centrifugal pump is one of the attractive choices in micro-hydropower development and industrial pressure energy recovery. One of the main problems in utilizing pump as turbine (PAT) is that the performance of PAT is usually not ideal due to the impeller with the routine backward curved blades which do not match well with turbine running condition. A cost effective way for solving this problem is to redesign impeller with forward curved blades from turbine working condition while the other components do not undergo any modifications. Impeller diameter is one of the main factors in impeller design. Therefore, research on the relationship of diameter and design flow rate and the influence of impeller diameter on PAT's performance is useful. In this paper, based on the constant velocity moment theory, calculation expression of volute constant within spiral volute was first developed and the velocity moment before impeller was acquired. Next, a relationship between impeller diameter and the critical design flow rate was deduced when the blade inlet angle was set to 90&deg;. To perform research on how impeller diameter influenced PAT's performance with forward curved blades, the outlet angles of three impellers with diameters of 235, 245 and 255 mm were calculated based on no-swirling outflow at the critical flow rate, respectively. And three impellers with the inlet angles of all equal to 90&deg; were designed by using ANSYS Bladegen software. Numerical simulation and analysis of the three PATs were performed using a verified computational fluid dynamics (CFD) technique. By comparison of three performance curves obtained by CFD, we found that the trend of three performance curves was similar and the impeller diameter had an obvious effect on the performance of PAT. The flow rate, required pressure head, generated shaft power, and efficiency at best-efficiency point (BEP) increased with increasing impeller diameter. The flow rates of three PATs at BEP were about 100, 110 and 120 m³/h, respectively as impeller diameter varied from 235 to 245 and 255 mm. Comparing the results obtained by CFD, we found that the flow rate at BEP was slightly larger than the designed flow rates predicted by using theoretical formulas. It was confirmed that the theoretical deduction was reasonable. In whole operating range, efficiency was lessened at small flow rate while increased at large flow rate in accordance with increasing impeller diameter. In operating range of flow rate lower than 90 m³/h, there was a sharp drop of efficiency in accordance with decreasing flow rate, which was primarily attributable to increase of hydraulic loss due to poor off-design performance and increase of disk friction loss due to increasing impeller diameter. The maximum overall efficiencies were obtained as 70.5%, 71.72% and 72.84% with impeller diameters varying from 235 to 245 and 255 mm, and PAT's efficiency at BEP increased by 1.73% and 3.32%, respectively. The PAT's efficiency with 255 mm inlet diameter maintained more than 70% at flow rates varying from 90 to 140 m³/h. The high efficiency operating range was more flat in accordance with increasing impeller diameter. This study provides a convenient way to design the special impeller with forward curved blades which can dramatically improve efficiency of PAT. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Computational fluid dynamics
Controlled terms:Centrifugal pumps - Computation theory - Cost effectiveness - Design - Flow rate - Hydraulic motors - Impellers - Models - Pumps - Turbine components  - Turbines - Turbomachine blades
Uncontrolled terms:Best efficiency point - Curved blades - Hydro-power development - Off-design performance - Pump as turbine (PAT) - Simulation and analysis - Theoretical formula - Volute constant
Classification code:601.2  Machine Components - 617  Turbines and Steam Turbines - 618.2  Pumps - 631  Fluid Flow - 632.2  Hydraulic Equipment and Machinery - 721.1  Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.5  Computer Applications - 911.2  Industrial Economics
Numerical data indexing:Percentage 1.73e+00%, Percentage 3.32e+00%, Percentage 7.00e+01%, Percentage 7.05e+01%, Percentage 7.17e+01%, Percentage 7.28e+01%, Size 2.55e-01m
DOI:10.11975/j.issn.1002-6819.2016.15.009

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 32>

Accession number:20163302706375
Title:Response of muskmelon growth to film covering, drip pipes density and irrigation lower limits in greenhouse
Authors:Wang, Jingwei (1, 2); Niu, Wenquan (1, 3); Zhang, Mingzhi (4); Li, Yuan (1) 
Author affiliation:(1) Institute of Soil and Water Conservation, Northwest A&amp;F University, Yangling; 712100, China; (2) The Center of Soil and Water Conservation Ecological Environment Construction of Shanxi Province, Taiyuan; 030002, China; (3) Institute of Soil and Water Conservation, CAS &amp; MWR, Yangling; 712100, China; (4) College of Water Resources and Architectural Engineering, Northwest A&amp;F University, Yangling; 712100, China 
Corresponding author:Niu, Wenquan(nwq@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:117-125
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the facilities agricultural production, different film-covering modes, drip irrigation pipe density and irrigation lower limits would create different soil water and thermal environment to affect crop growth and yield. Therefore, it would be more meaningful to explore and allocate reasonable film-covering modes, drip irrigation pipe density and irrigation lower limits to improve the soil ecological environment and increase agricultural production. In the study, orthogonal experiment was designed to demonstrate the effects of different film-covering modes, drip irrigation pipe density and irrigation lower limits on the muskmelon growth, photosynthetic efficiency, biomass, yield and water use efficiency in greenhouse, and to analyze the relationship between the yield and the plant growth, biomass, and photosynthetic efficiency. The experiment was carried out in a greenhouse in Da Zhai Village of Da Zhai Town, Shaanxi Province during April-July, 2014. The greenhouse is 108 m long (east-west) and 8 m wide (north-south), which is located at longitude 108&deg;08'E and latitude 34&deg;16 'N, with an elevation of 521 m. The experiment site has warm and semi-humid monsoons climate, with annual average temperature of 16.3&#8451;, annual average rainfall of 535.6 mm, annual average sunshine of 2163 h, and annual average frost-free period of 210 d. In the orthogonal experiment, the film-covering modes had three levels, as full, half and no film-covering (P<inf>F</inf>, P<inf>H</inf>, P<inf>N</inf>). P<inf>F</inf>was set as that the furrow ridge, inter-row and rows of the cultivated areas were all covered with film. And, the furrow ridge of the cultivated area was covered with film for the P<inf>H</inf>level. There was no film covering for cultivated area in the P<inf>N</inf>level. Drip pipe density was divided into three levels: 1) 1 pipe for 1 line (T<inf>1</inf>), 1 drip pipe was placed in every plant row, near to the base of the plant; 2) 3 pipes for 4 lines (T<inf>3/4</inf>), 3 drip pipes were placed into every 4 inter-row spaces with 30 cm separation between drip pipe and plant; 3) 1 pipe for 2 lines (T<inf>1/2</inf>), 1 drip pipe was placed midway between 2 plant rows with 30 cm separation between drip pipe and plant and 2 plant rows between each drip line. Irrigation lower limit also had three levels, 60%, 70% and 80% of field capacity (L<inf>60</inf>, L<inf>70</inf>, L<inf>80</inf>) corresponding to the upper limits of 65%, 75% and 85%. In the experiment, soil physical indicators, such as the average soil temperature, the soil moisture content range and pH were determined. The muskmelon growth rate of plant height and stem diameter were also measured. And, the evaluation indexes of photosynthesis, as the chlorophyll, photosynthetic rate and leaf area index (LAI), were also determined. Additional, the plant biomass, the melon yield, irrigation amount and IWUE (Irrigation water use efficiency) were also measured. The stepwise regression analysis was used to explore the correlation of these indicators directly to determine the best agronomic measures in greenhouse. The results showed that the P<inf>H</inf>level could create higher temperature and more uniform distribution of moisture in the root zone soil, therefore this treatment had better root fresh weight, root-top ratio and leaf area index than that with P<inf>F</inf>and P<inf>N</inf>level. The P<inf>H</inf>level also had significantly higher soil urease and phosphatase activities than the P<inf>F</inf>and P<inf>N</inf>level. It could enhance the muskmelon's biomass, yield and IWUE in greenhouse. The drip irrigation pipe density had a great influence on melon yield. The fresh weight and dry weight of muskmelon plant under the T<inf>3/4</inf>were less than that under T<inf>1</inf>and T<inf>1/2</inf>, but the stem diameter, fresh weight of root and root-top ratio were higher. And T<inf>3/4</inf>was benefit for muskmelon to absorb more nutrients and to distribute more photosynthetic products for the fruit, so yield under this treatment had increased by 8.56% and 8.56% respectively than that under T<inf>1</inf>and T<inf>1/2</inf>. The irrigation lower limits was an important factor for muskmelon growth and yield. L<inf>70</inf>had made the muskmelon plant growing more balance and increased yield 22.58% and 2.42% than L<inf>60</inf>and L<inf>80</inf>respectively. IWUE values under P<inf>F</inf>and P<inf>H</inf>level were 57.21% and 56.41% higher respectively than the P<inf>N</inf>level, IWUE of T<inf>3/4</inf>was 3.54% and 0.80% higher respectively than that of T<inf>1</inf>and T<inf>1/2</inf>, and the IWUE of L<inf>70</inf>was 58.46% higher than that of L<inf>80</inf>. Therefore, the half film-covering mode (P<inf>H</inf>), drip irrigation pipe density of 3 pipes for 4 lines (T<inf>3/4</inf>) and 70% field capacity (L<inf>70</inf>) would be recommended for melon cultivation in the greenhouse. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:40
Main heading:Irrigation
Controlled terms:Agriculture - Biomass - Cultivation - Ecology - Efficiency - Film growth - Films - Greenhouses - Moisture - Rain  - Regression analysis - Soil moisture - Soils - Subirrigation - Water supply
Uncontrolled terms:Agricultural productions - Ecological environments - Irrigation water use efficiency - Lower limits - Muskmelon - Photosynthetic efficiency - Stepwise regression analysis - Yield
Classification code:443.3  Precipitation - 446.1  Water Supply Systems - 454.3  Ecology and Ecosystems - 483.1  Soils and Soil Mechanics - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1  Production Engineering - 922.2  Mathematical Statistics
Numerical data indexing:Percentage 2.26e+01%, Percentage 2.42e+00%, Percentage 3.54e+00%, Percentage 5.64e+01%, Percentage 5.72e+01%, Percentage 5.85e+01%, Percentage 6.00e+01%, Percentage 6.50e+01%, Percentage 7.00e+01%, Percentage 7.50e+01%, Percentage 8.00e+01%, Percentage 8.00e-01%, Percentage 8.50e+01%, Percentage 8.56e+00%, Size 1.08e+02m, Size 3.00e-01m, Size 5.21e+02m, Size 5.36e-01m, Size 8.00e+00m, Time 7.79e+06s
DOI:10.11975/j.issn.1002-6819.2016.15.017

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 33>

Accession number:20163302706380
Title:Dynamic monitoring rice delayed type chilling damage based on remote sensing in northeast China
Authors:Liu, Dan (1); Yu, Chenglong (1); Du, Chunying (1) 
Author affiliation:(1) Heilongjiang Province Institute of Meteorological Sciences, Harbin; 150030, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:157-164
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rice chilling damage remains one of the major agricultural disasters in northeast China. Remote sensing technology can easily monitor this disaster on a relatively large scale. Satellites and ground multi-source data were used in this study to monitor rice delayed- type chilling damage by combining with extraction results of rice planting area, growth stage calculation and spatial distribution of static development stage. Based on these results, we can provide technical supports for the agricultural production sectors to monitor rice chilling damage in the wide area and to improve rice quality and yield. Using remote sensing data, daily mean temperature of 196 meteorological stations located in northeast China from 2000 to 2009, rice development stages and related geographic information data, the degree of rice chilling damage and main year of chilling damage were analyzed according to technical specifications for evaluation of rice cold damage. The information of rice planting area was extracted by the products of MODIS MCD12Q1 and Landsat data. Normal differential vegetation Index (NDVI) and Enhanced Vegetation Index (EVI) were acquired from the products of MODIS MCD12Q1. The reference range of NDVI and EVI for development stages of rice was divided by the method of statistical analysis. According to the correlation between Julian days of rice development stages and geographical factors, the regression equations of rice development stages were constructed. On the basis of the equations, daily distribution maps of development stages were obtained by a piece of sliding filter board through ENVI+IDL. Finally, monitoring of rice delayed-type chilling damage was done based on remote sensing in northeast China on May 24, 2009 and August 7, 2009. The results showed that the large-range distribution of damage happened in 2002, 2003, 2008 and 2009 in northeast China. Heilongjiang province was particularly affected by the disaster. Also, both of NDVI and EVI values of rice in each development stage obeyed the normal distribution. But the accuracy rate of EVI values in determining the rice development stages was over 76%. Obviously, EVI values were more effective than NDVI values in detecting rice phenology. In addition, rice development stage models were established according to the relationship between longitude, latitude, altitude and day series. The dates of simulated rice development stages were earlier than the actual observation dates as a whole with an error of 1 to 3 days. And the difference days in simulated results and observed values were much smaller than that between two rice development stages. The estimate accuracy can meet the need of the research. Moreover, on the basis of models, we made the spatial distribution maps of every static development stage and answered how to confirm the ownership of the rice development stages by infinite function. Finally, rice delayed-type chilling damage was dynamically monitored in two days by using this method. The monitoring results had a better consistence with the observational records in time and space. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Remote sensing
Controlled terms:Agriculture - Crops - Disasters - Monitoring - Normal distribution - Radiometers - Space optics - Spatial distribution - Vegetation
Uncontrolled terms:Agricultural productions - Delayed-type chilling damage - Development stages - Enhanced vegetation index - Northeast China - Paddy - Remote sensing technology - Spatial distribution map
Classification code:656.1  Space Flight - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products - 921  Mathematics - 922.1  Probability Theory - 944.7  Radiation Measuring Instruments
Numerical data indexing:Age 2.74e-03yr to 8.22e-03yr, Percentage 7.60e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.022

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 34>

Accession number:20163302706385
Title:Laser-induced breakdown spectroscopy for determining content of Pb and Cd in soil
Authors:Yu, Keqiang (1, 2); Zhao, Yanru (2); Liu, Fei (2); He, Yong (2) 
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&amp;F University, Yangling; 712100, China; (2) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou; 310058, China 
Corresponding author:He, Yong(yhe@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:197-203
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, a large tract of farmland or soil may be contaminated by heavy metal, which could make agricultural products polluted, bringing a harmful effect on human health. Hence, it is necessary to determine the heavy metal concentration in farmland soil. Rapid detection of heavy metals in soil is a key point of information acquirement tools in precision agriculture, and it also provides a base on prevention soil heavy metal pollution and sustainable development of agriculture. The traditional techniques for determining heavy metals is high in cost, time-consuming, use of large amount of chemicals, complex in sample preparation, and expensive in experimental device, etc. Laser-induced breakdown spectroscopy (LIBS), a form of atomic emission spectroscopy (AES), is regarded as a useful tool for rapid, real-time and in situ measurements because of its unique characteristics, such as no or less sample preparation, multi-element analysis, direct measurement without contact with the materials, stand-off or remote analysis and high detecting speed. Relying on those unique capabilities, LIBS technique has a tremendous growth and been widely applied in variety of areas, such as environmental monitoring, geological applications, biomedical detection, industrial analysis, agriculture and food. In order to evaluate the feasibility of determining the heavy metals in soil, in this research, we employed LIBS technology combined with calibration curve and chemometrics methods to quantitatively analyze the content of Pb and Cd in soil samples. Soil samples with different Pb and Cd concentration were prepared. A laboratorial LIBS device working in air was employed to obtain the spectra of soil samples. Based on analysis of LIBS curves and the data from atomic spectra database in national institute of standards and technology (NIST), emission lines at Pb I 405.78 and Cd I 361.05 nm (I was atomic spectral line) were identified as characteristic lines. Then, models and calibration curves based on LIBS intensity, Lorentz fit intensity after normalized, peak areas and corresponding content were established and fitted. For Pb element, the linear relationships of coefficient of determination (R²) of three methods were: 0.98385, 0.97097 and 0.99321, respectively. And Cd element failed to provide an effective linear relationship. Meanwhile, PLSR (Partial Linear Square Regression) model for predicting Pb and Cd were built and results demonstrated that the calibration curve and PLSR model provided similar performance, resulting in correlation coefficient of 0.9485 and root mean square error of 2.044 mg/g in the prediction set. And PLSR model for Cd element prediction revealed the promising results, resulting in correlation coefficient of 0.9949 and root mean square error of 97.05 &mu;g/g in the prediction set. The achievements of the research not only provides a guide for detecting heavy metals in soil, but also lays a theoretical foundation for development of the portable LIBS detector used in the field. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Soil pollution
Controlled terms:Agricultural products - Agriculture - Air quality - Atomic emission spectroscopy - Atomic spectroscopy - Atoms - Cadmium - Calibration - Emission spectroscopy - Farms  - Forecasting - Heavy metals - Iodine - Laser induced breakdown spectroscopy - Lead - Least squares approximations - Mean square error - Metal analysis - Soil surveys - Soils  - Spectroscopic analysis - Spectroscopy - Spectrum analysis - Sustainable development
Uncontrolled terms:Calibration curves - Coefficient of determination - Environmental Monitoring - Heavy metal concentration - Information acquirements - Laserinduced breakdown spectroscopy (LIBS) - National Institute of Standards and Technology - Partial least squares regression
Classification code:451.2  Air Pollution Control - 483.1  Soils and Soil Mechanics - 531  Metallurgy and Metallography - 546.1  Lead and Alloys - 549.3  Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 801  Chemistry - 804  Chemical Products Generally - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4  Agricultural Products - 921.6  Numerical Methods - 922.2  Mathematical Statistics - 931.1  Mechanics - 931.3  Atomic and Molecular Physics
Numerical data indexing:Size 3.61e-07m
DOI:10.11975/j.issn.1002-6819.2016.15.027

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 35>

Accession number:20163302706359
Title:High value-added reutilization approach for waste biomass materials
Authors:He, Yufeng (1); Qian, Wenzhen (1); Wang, Jianfeng (1); Xiong, Yubing (1); Song, Pengfei (1); Wang, Rongmin (1) 
Author affiliation:(1) Key Laboratory of Eco-Environment-Related Polymer Materials of Ministry of Education, College of Chemistry &amp; Chemical Engineering, Northwest Normal University, Lanzhou; 730070, China 
Corresponding author:Wang, Rongmin(wangrm@nwnu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:1-8
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In past decades, with the development of modern industry, more and more non-renewable fossil resources, such as oil and coal, have been applied to fabricate materials and fuel. It promotes the prosperity of material civilization of human society, but it also causes biomass resources to be discarded and wasted, and results in serious pollution of environment. Therefore, the way to develop the biomass resource, especially the reusing of disused biomass resources has been attracted considerable attentions from governments and scientists over the world. In this paper, based on introducing main resources of waste biomass materials and their traditional processing method, according to the latest research development trends in recent years, the novel pathway for the reutilization of waste biomass materials has been summarized. Waste biomass sources are very extensive and there are varied ways in treating and using these materials. Main sources of waste biomass materials are waste of agricultural production, subsidiary agricultural products, food processing waste, forestry and urban greening waste and life rubbish. Currently, more than 1 billion tons of solid wastes are generated per year in cities of world, and waste generation rates will be more than double over the next 20 years in lower income countries. As the ingredients of biomass wastes are complex, dealing it with improper ways will damage environment and people's health seriously. The traditional methods for processing waste biomass mainly include combustion, feed, fertilizer and matrix. The advantages of these treats are simple operation, high yield and low running charge. However, it can not only cause serious hazards to ecological environment, but also cause the waste of resources. Therefore, more and more technologies for reusing discarded biomass have been developed. A typical ecologic friendly comprehensive technology for reutilization of discarded straw is edible fungi cultivation - feeding pig-biogas generation-fertilizing the soil. In some discarded biomass, the active ingredients or biopolymers can be extracted and applied to medicine or any other regions. A great number of natural polymers can also be extracted from discarded biomass, and used to prepare polymer materials, such as lignin, cellulose, starch, chitin, chitosan, humic acid and protein. Using bio-refinery, the discarded biomass can be cut down, and the obtained different monomers can be used to prepare bio-based polymer materials, such as polylactic acid (PLA), polyglycolic acid (PGA), poly vinyl alcohol (PVA), poly(butylene succinate) (PBS), and poly(itaconic acid) (PIA). In recent years, it is found that the biosynthesis is a kind of effective method for preparing degradable polymer materials, such as polyhydroxyalkanoates (PHA), poly-g-glutamic acid (g-PGA), e-Poly-L-Lysine (e-PL), poly(b-malic acid) (b-PMLA), poly (butyleneadipate-co-terephthalate) (PBAT), and poly(propylene carbonate) (PPC). With the progress in characterization and synthesis, more and more novel polymer materials with different functions have been prepared, such as biomedical polymers, smart polymers, energy materials, nano materials and catalytic materials. In summary, it is an important development trend to prepare the novel matrix and functional material from waste biomass. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:95
Main heading:Characterization
Controlled terms:Agricultural products - Agriculture - Amino acids - Biochemistry - Biological materials - Biomass - Biopolymers - Chitin - Coal combustion - Coal deposits  - Coal industry - Cultivation - Food processing - Functional materials - Functional polymers - Natural polymers - Oils and fats - Processing - Straw - Waste incineration  - Waste utilization - Wastes
Uncontrolled terms:Agricultural productions - Comprehensive technology - Ecological environments - Food processing wastes - Poly(butylene succinate) - Poly(propylene carbonate) - Resource utilizations - Traditional processing
Classification code:452.4  Industrial Wastes Treatment and Disposal - 461.2  Biological Materials and Tissue Engineering - 503  Mines and Mining, Coal - 521  Fuel Combustion and Flame Research - 524  Solid Fuels - 801.2  Biochemistry - 804.1  Organic Compounds - 815.1  Polymeric Materials - 815.1.1  Organic Polymers - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 822.2  Food Processing Operations - 913.4  Manufacturing - 951  Materials Science
Numerical data indexing:Age 2.00e+01yr
DOI:10.11975/j.issn.1002-6819.2016.15.001

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 36>

Accession number:20163302706395
Title:Parameter optimization of hickory nut drying by phased varying power microwave
Authors:Zhu, Dequan (1); Ma, Jin (1); Jiang, Rui (1); Yuan, Jiahong (1); Wang, Chaoxian (1); Zhu, Hong (1) 
Author affiliation:(1) School of Engineering, Anhui Agricultural University, Hefei; 230036, China 
Corresponding author:Jiang, Rui(jiangrui@ahau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:268-274
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hickory (Carya cathayensis Sarg) is an endemic tree species in China, whose nut is worldwide famous for nutrition. The nut is rich in protein and oleic acid, linoleic acid and other unsaturated fatty acids. In addition, the nut has a variety of essential amino acids and mineral elements. Drying is an important but weak link in processing of walnut products. At present, drying method for the nut usually uses traditional hot air drying, which consumes high energy together with low drying efficiency and poor product quality. Microwave drying technology has the several advantages over the traditional method, which include high efficiency, energy saving, sanitation, high product quality and automatic control. It has been widely used in the drying processes of fruits and vegetables. Currently, most of nuts, such as macadamia nuts, cashew nut, Chinese chestnut and pistachio nuts, are dried by using constant power microwave. Although constant power microwave method is easy to operate and control, the treated nut is easy to be over-dried or burned. Furthermore, the uneven moisture diffusion and high speed of heat and mass transfer generated in the late stage of drying process of constant power microwave reduce the original nutrients and the sense quality. Recent researches have indicated that phased varying power microwave drying method can overcome these problems. In order to improve the?product quality, shorten the drying process and reduce drying energy consumption, the phased varying power microwave was used to dry hickory nuts. The technical parameters such as pre-microwave power, moisture content after pre-drying and later microwave power were optimized in this experiment. First, the appropriate range of the various factors of the microwave drying of the hickory nuts was determined by using the single factor experimental method. Then, by using the three-factor and five-level quadratic regression orthogonal experimental method, the relationships between the 3 factors and dehydration rate, energy consumption of drying process, protein retention rate, unsaturated fatty acid retention rate and overall score of sensory quality indicator of dried nuts were analyzed. The regression mathematical models based on experimental indices and factors were established and used to analyze the influence degree of 3 factors on drying process. Finally, the optimal process parameter combination was obtained for drying hickory nuts using the phased varying power microwave through multi-objective nonlinear optimization method. These combinations were as follows: pre-drying microwave power was 6.5 kW/kg, water content of conversion point was 23.4% (dry basis), and late drying microwave power was 3.3 kW/kg. By using these optimized conditions, dehydration rate was 4.072%/min, energy consumption was 3.467 kW&middot;h/kg, protein retention rate was 92.15%, unsaturated fatty acid retention rate was 91.63% and overall score for sensory quality indicator was 35.28 for dried hickory nuts. Our results provide theoretical reference for drying production of hickory nuts. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Drying
Controlled terms:Automation - Dehydration - Energy conservation - Energy efficiency - Energy utilization - Fatty acids - Linoleic acid - Mass transfer - Microwave generation - Microwave heating  - Microwaves - Minerals - Models - Moisture - Multiobjective optimization - Nonlinear programming - Optimization - Proteins - Quality control - Thermal processing (foods)  - Unsaturated fatty acids
Uncontrolled terms:Drying energy consumption - Essential amino acids - Fruits and vegetables - Heat and mass transfer - Hickory nuts - Nonlinear optimization methods - Optimized conditions - Parameter optimization
Classification code:482.2  Minerals - 525.2  Energy Conservation - 525.3  Energy Utilization - 641.3  Mass Transfer - 711  Electromagnetic Waves - 711.1  Electromagnetic Waves in Different Media - 713.2  Oscillators - 731  Automatic Control Principles and Applications - 802.2  Chemical Reactions - 804.1  Organic Compounds - 822.2  Food Processing Operations - 913.3  Quality Assurance and Control - 921.5  Optimization Techniques
Numerical data indexing:Percentage 2.34e+01%, Percentage 9.16e+01%, Percentage 9.22e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.037

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 37>

Accession number:20163302706401
Title:Review on astaxanthin production from agricultural wastes by Phaffia rhodozyma
Authors:Zhou, Guixiong (1); Wang, Wen (1); Tan, Xuesong (1); Zhuang, Xinshu (1); Yuan, Zhenhong (1); Qi, Wei (1); Yu, Qiang (1); Wang, Qiong (1); Miao, Changlin (1); Wang, Yao (1) 
Author affiliation:(1) Key Laboratory of Renewable Energy, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou; 510640, China 
Corresponding author:Yuan, Zhenhong(yuanzh@ms.giec.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:308-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Astaxanthin production by Phaffia rhodozyma is environmentally friendly, safe, and cost effect, but the cost of the medium for culture of Phaffia rhodozyma especially carbon sources is one of the major factors that constrain this process from achieving massive production. Using cheap and widely sourced raw materials such as saccharides, low-value starch, glycerol, and waste lignocelluloseas carbon sources can effectively reduce the cost. In this paper, we summarized the current use of Phaffia rhodozyma to produce astaxanthin, and systematically reviewed, compared, and analyzed domestic and foreign studies on astaxanthin production by Phaffia rhodozyma using different carbon sources. Conventional use of pure sugar such as glucose, sucrose and xylose as a carbon source for astaxanthin production by Phaffia rhodozyma has good effects, but is applicable only in laboratory studies and in small-scale fermentation due to its high costs. Fruit, when used as a carbon source for astaxanthin production by Phaffia rhodozyma, has wide resources and is easy to pretreat, suitable for microbial growth and widely used for astaxanthin production. However, due to the seasonal fluctuations and geographical limitations on fruit, it is difficult to promote the use of fruit as a carbon source for astaxanthinproduction by Phaffia rhodozyma on a large scale. Molasses, which has a high sugar content and is subject to a wide supply, is a good carbon source. However, using it for astaxanthin production may result in competing resource with other industries (such as fuel alcohol). Therefore, the stability of its supply cannot be ensured. When glycerin is used as a carbon source for astaxanthin production by Phaffia rhodozyma, not only can Phaffia rhodozyma grow well, but astaxanthin also accumulates steadily in the body of Phaffia rhodozyma. However, it is difficult to obtain high-purity glycerin. Crude glycerol generated during biodiesel production contains a lot of impurities (such as methanol), which can significantly affect microbial growth and astaxanthin accumulation, and may also have food safety issues. Lignocellulose has a variety of sources, which primarily include some agricultural or forest waste such as straw, wood chips, and corn fiber. Currently, a popular application of lignocellulose is the preparation of fuel ethanol, but the utilization of xylose poses a major obstacle to the preparation of fuel ethanol using lignocellulose. Phaffia rhodozyma can make efficient utilization of xylose. Therefore, lignocellulose is a very promising raw material that can be used for large-scale and low-cost fermentative astaxanthin production. However, its utilization suffers from the following technological bottlenecks: complicated pre-treatment; the inhibitory substances to microbial growth produced from acid hydrolysis need to be detoxified, which can result in a decrease in astaxanthin production efficiency; and, the high cost and inefficiency of cellulase used for hydrolyzing lignocellulose, which makes it costly to prepare reduced sugars using lignocellulose and produce astaxanthin. Based on these, future studies on the carbon sources for astaxanthin production by Phaffia rhodozyma should focus on the development of more cheap carbon sources or the comprehensive utilization of multiple carbon sources, while aiming to overcome technological bottlenecks that restrict the use of lignocellulose as a carbon source. Finally, the future trends in and key research directions for the carbon sources used for astaxanthin production by Phaffia rhodozyma were envisaged. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:44
Main heading:Cellulose
Controlled terms:Agricultural wastes - Agriculture - Carbon - Cost reduction - Costs - Ethanol - Food safety - Fruits - Fuels - Glycerol  - Hydrolysis - Lignin - Microorganisms - Sugars - Wastes - Wood - Wood products
Uncontrolled terms:Astaxanthin - Comprehensive utilizations - Different carbon sources - Geographical limitations - Lignocelluloses - Phaffia rhodozyma - Production efficiency - Seasonal fluctuations
Classification code:461.6  Medicine and Pharmacology - 461.9  Biology - 802.2  Chemical Reactions - 804  Chemical Products Generally - 804.1  Organic Compounds - 811.2  Wood and Wood Products - 811.3  Cellulose, Lignin and Derivatives - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 911  Cost and Value Engineering; Industrial Economics
DOI:10.11975/j.issn.1002-6819.2016.15.043

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 38>

Accession number:20163302706397
Title:High-throughput online detection method of egg size and shape based on convex hull algorithm
Authors:Duan, Yufei (1); Wang, Qiaohua (1, 2); Li, Xiaoming (1); Tang, Yihua (1) 
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China; (2) National Research and Development Center for Egg Processing, College of Food Science and Technology, Huazhong Agricultural University, Wuhan; 430070, China 
Corresponding author:Wang, Qiaohua(wqh@mail.hzau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:282-288
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Size and shape of egg are the important indices which need to be investigated in egg packaging, marketing and selection of fertile eggs. Currently, high-throughput online detection is required in commercialization processing of egg. In order to achieve high-throughput online detection and grading for the size and shape of eggs, industrial camera (IDS company, UI-2210RE-C-HQ) was used to capture group egg images dynamically on transport mechanism, which reached 30 000 eggs per hour about its throughput in this study. There were 6 eggs that needed to be processed in each picture. Firstly, some light leaks produced by the clearances of transport mechanism were eliminated by deducting double green component from red component. Then Otsu's method was used for threshold segmentation based on the different information characteristics of each egg image. After binaryzation, hole filling was performed, the 2 2 circle structure elements were used to remove burrs on edge of egg, and then small area removing method was adopted in image pretreatment. Good effect was obtained in most of egg images, which presented the whole shape of egg. However, incomplete shape existed in some images after pre-processing due to the color similarity between light leak and part area of the egg. Therefore, the method of least-squares ellipse fitting was used to supplement the outline of egg, but unsatisfactory effect was showed from the fitting result. Concave had a bad effect on the fitting result and was required to remove. In order to remove the concave points of the outline better, the convex hull algorithm in the computational geometry was applied. Better effect was showed in the image with the method of least-squares ellipse fitting combined with convex hull algorithm, and the fitting outline of egg was more close to the actual outline. Size of egg was described by major and minor axis, and oblate degree was described by egg shape index. Sixty eggs were selected randomly to get actual axis sizes and the number of axis pixels. The correlation coefficient between the size of actual major axis and the number of fitting major axis pixels obtained by direct least-squares ellipse fitting was 0.8228, and 0.8620 for the minor axis. The correlation coefficient by the method of least-squares ellipse fitting combined with convex hull algorithm was 0.9566 and 0.9439 respectively for the major and the minor axis. By comparing the correlation coefficient from 2 methods, the method combined with convex hull algorithm was more proper. For testing the accuracy of grading, a request of size grading with the Z8-X type egg packing box was formulated, and the shape grading was based on the influence of egg shape index on hatchability. Eighty-four eggs were selected randomly to classify, and the accuracy of size and shape reached 90.5% and 89.3%, respectively. The experiment result shows that the image processing methods have a good effect on extracting the characteristic parameters of egg size and shape quickly and accurately, and among the methods, convex hull algorithm is of great significance. This method is believed to be feasible for the high-throughput online detection of egg size and shape, which can fulfill the requirements of production. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:21
Main heading:Throughput
Controlled terms:Algorithms - Computational geometry - Computer vision - Geometry - Grading - Image acquisition - Image processing - Image segmentation - Least squares approximations - Nondestructive examination  - Pixels - Processing
Uncontrolled terms:Correlation coefficient - High throughput - Image processing - methods - Method of least squares - On-line detection method - Shape - Size - Threshold segmentation
Classification code:723  Computer Software, Data Handling and Applications - 723.5  Computer Applications - 913.4  Manufacturing - 921  Mathematics
Numerical data indexing:Percentage 8.93e+01%, Percentage 9.05e+01%
DOI:10.11975/j.issn.1002-6819.2016.15.039

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 39>

Accession number:20163302706378
Title:Effects of planting year and density on deep soil desiccation of apple orchards in Weibei dryland
Authors:Bao, Rui (1, 2); Zou, Yangjun (1, 2); Ma, Fengwang (1, 2); She, Xiaofeng (3); Dang, Zhiming (3); He, Wuchun (1, 2) 
Author affiliation:(1) College of Horticulture, Northwest A&amp;F University, Yangling; 712100, China; (2) Apple Experiment Station of Northwest A&amp;F University, Luochuan; 727400, China; (3) Luochuan Institute of Apple Research, Luochuan; 727400, China 
Corresponding author:Zou, Yangjun(zouyangjun@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:143-149
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to explore the effects of planting year and density on deep soil desiccation of apple orchards in Weibei dryland, soil moisture deep to 15 m belowground were measured twice for 5 apple orchards with different planting year and density in 2008 and 2015, respectively, and cropland was used as control. The results showed that: 1) the soil desiccation index (SDI) measured in 2008 for 5, 10, 15, 20 and 25 a were 6.46%, 32.68%, 37.65%, 63.33% and 62.81%, while SDI for the same orchard 7 years later were 35.98%, 59.65%, 42.21%, 75.06% and 70.09%, respectively, indicated that the longer the planting year was, the higher the SDI was. In addition, the degrees of soil desiccation were quickly from 5 to 12 a and 10 to 17 a, the increasing proportion per year were 4.22% and 3.85% averagely, but slowly from 20 to 27 a with an increasing proportion of 1.7%. The soil desiccation of 5 a apple orchard was slight and the soil moisture was close to cropland, and after planting 15 a, the soil desiccation spread to 11 m belowground (paleosol layer), and to 17 a, the buffer function of paleosol layer was lost and if the rainfall in a year cannot meet the water consumption of apple trees, the quality and yields would be limited by and linearly dependent on annual rainfall. 2) Thinning could slow the soil desiccation process. The orchards with a planting density of 4 m&times;6 m (15 a, 25 a) had significantly lower rates of soil desiccation during 7 years, with an average of 0.65% and 0.61% per year, respectively. The soil desiccation index of 22 a orchard was 42.21%, which was 17.44% and 32.85% less compared to orchards of 17 a and 27 a, respectively. In addition, the soil moisture of 2-5 m layer with thinning treatment was higher than the non-thinning treatment, indicating orchards with lower density could compensate soil water in deep layer by rainfall in a wet year. However, in a dry year, even for the orchard with lower density, the water consumption of trees would be inevitable to be compensated by deep soil water, which was more common in old orchard, and thinning can only delay the formation of soil dry layer. Therefore, this study suggested corresponding measures should be taken around 12 a after planting, before the soil desiccation expanded to the paleosol layer. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Soils
Controlled terms:Driers (materials) - Farms - Forestry - Fruits - Moisture - Orchards - Rain - Soil moisture
Uncontrolled terms:Buffer functions - Corresponding measures - Dryland - Planting density - Planting year - Soil desiccations - Thinning treatment - Water consumption
Classification code:443.3  Precipitation - 483.1  Soils and Soil Mechanics - 803  Chemical Agents and Basic Industrial Chemicals - 821  Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Age 7.00e+00yr, Percentage 1.70e+00%, Percentage 1.74e+01%, Percentage 3.27e+01%, Percentage 3.29e+01%, Percentage 3.60e+01%, Percentage 3.76e+01%, Percentage 3.85e+00%, Percentage 4.22e+00%, Percentage 4.22e+01%, Percentage 5.96e+01%, Percentage 6.10e-01%, Percentage 6.28e+01%, Percentage 6.33e+01%, Percentage 6.46e+00%, Percentage 6.50e-01%, Percentage 7.01e+01%, Percentage 7.51e+01%, Size 1.10e+01m, Size 1.50e+01m, Size 2.00e+00m to 5.00e+00m
DOI:10.11975/j.issn.1002-6819.2016.15.020

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 40>

Accession number:20163302706360
Title:Analysis and test of influence of revolute joint clearance on performance of crank-rocker style transplanting mechanism
Authors:Liu, Faxin (1); Wu, Chuanyu (1, 2); Sun, Liang (1, 2) 
Author affiliation:(1) College of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou; 310018, China; (2) Key Laboratory of Transplanting Equipment and Technology of Zhejiang Province, Hangzhou; 310018, China 
Corresponding author:Wu, Chuanyu(cywu@zstu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:9-17
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Generally, revolute joints are considered to be ideal in dynamic analysis of crank-rocker type transplanting mechanism. However, in reality, clearances in revolute joints are unavoidable due to uncertainties such as manufacturing tolerances, assembly errors and wear. When a revolute joint clearance is introduced, the relative position of the axle pin and axle cover is uncertain, which will affect the dynamic responses of the transplanting mechanism. In order to investigate the influence of the revolute joint clearance on the crank-rocker type transplanting mechanism, the dynamic model of the crank-rocker type transplanting mechanism with a revolute joint clearance was established based on the dynamics theory and the Lankarani-Nikravesh contact force model. The revolute joint clearance will introduce 2 extra degrees of freedom, and a stable solution cannot be obtained by solving the dynamic directly, so the dynamic model was solved by the four-order Runge- Kutta method. The parameters of the simulation calculation were obtained according to the actual parameters of transplanting mechanism and literatures. The influence of revolute joint clearance on trajectory, velocity, acceleration and taking seedling position of the needles to take seedlings was analyzed by Matlab. The results showed that the revolute joint clearance had little influence on trajectory, velocity and taking seedling position of the needles to take seedlings, and the revolute joint clearance had great influence on acceleration of the needles to take seedlings; with the increase of revolute joint clearance, the deviation of taking seedling position of transplanting mechanism would be greater, and the amplitude and fluctuation range of acceleration of the needles to take seedlings would increase. In order to quantitatively describe the influence of various revolute joint positions with clearance on acceleration of the needles to take seedlings, the average acceleration was used as the evaluation criterion of the influence. In addition to the revolute joint connected to the drive, the average accelerations of 3 various revolute joints with various clearances were obtained by simulation analysis. For the 3 revolute joint clearances, the revolute joint clearance between the crank and the connecting rod had the greatest influence on acceleration of the needles to take seedlings according to the comparison result of the average accelerations. The continuous contact model was also used to analyze the influence of the revolute joint clearance on acceleration. In order to verify the correctness of the simulation analysis and to select the simulation model whose calculation results were more in line with the actual ones, a test bench was established. An accelerometer and a data acquisition and analysis system were used to measure acceleration of the needles to take seedlings. In the test, the rolling bearing was regarded as ideal revolute joint, and the fit between sliding bearing and shaft with different radii was regarded as the revolute joint with clearance. The average acceleration of the test was larger than that of the simulation under the same condition due to some factors such as manufacturing tolerances, clearance of the rolling bearing and vibration. The conclusion that the revolute joint clearance between the crank and the connecting rod has the greatest influence on acceleration can be also obtained according to the test. By comparing the test and simulation results, the Lankarani-Nikravesh contact force model is more suitable for the analysis of the mechanism with revolute joint clearance than the continuous contact model. The relative errors of average acceleration between simulation based on the Lankarani-Nikravesh contact force model and test were within 3.6% under revolute joint C or D with clearance. The relative errors of average acceleration were within 8.1% under revolute joint B with clearance. The same conclusions can be obtained with the average accelerations of simulation and the average accelerations of test. So the correctness of simulation analysis based on the Lankarani-Nikravesh contact force model was verified by the test results. This research provides the reference for structural optimization design and accuracy allocation of crank-rocker type transplanting mechanism. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Acceleration
Controlled terms:Axles - Bearings (machine parts) - Connecting rods - Data acquisition - Degrees of freedom (mechanics) - Digital storage - Dynamic models - Dynamics - End effectors - Errors  - Manufacture - MATLAB - Mechanics - Models - Needles - Roller bearings - Runge Kutta methods - Structural optimization - Testing
Uncontrolled terms:Clearance - Crank rocker - Data acquisition and analysis system - Manufacturing tolerances - Revolute joints - Simulation calculation - Structural optimization design - Transplanting mechanisms
Classification code:537.1  Heat Treatment Processes - 601.2  Machine Components - 722.1  Data Storage, Equipment and Techniques - 723.2  Data Processing and Image Processing - 731.5  Robotics - 921  Mathematics - 931.1  Mechanics
Numerical data indexing:Percentage 3.60e+00%, Percentage 8.10e+00%
DOI:10.11975/j.issn.1002-6819.2016.15.002

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 41>

Accession number:20163302706362
Title:Bionic design and dynamics performance simulation of walking wheel to travel on sand
Authors:Zhang, Rui (1); Ji, Qiaoli (1); Zhang, Sihua (1, 2); Li, Jianqiao (1) 
Author affiliation:(1) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun; 130022, China; (2) China Electronics Technology Group Twenty-eighth Research Institute, Nanjing; 210007, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:26-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is important to enhance the traveling ability of wheel in the loose sand circumstance. According to the morphology structure and the movement mode of ostrich foot, a new bionic walking wheel to travel on sand was developed, using the theory of bionic engineering and the design concept, which combined the traditional wheel walking mechanism that had the advantages of simple structure and high speed and leg foot type robot that had the advantage of resistance to sink. African ostrich is highly cursorial bipedal animal on land with a permanently elevated metatarsophalangeal joint supported by only 2 toes. They are also acknowledged as the fastest bipedal animal on land with extraordinary endurance during locomotion. The ostrich is capable of running at very high speeds and can run steadily for 30 min at a speed exceeding 50 km/h and move at a speed of 70 km/h for short sprints, with a step length reaching up to 5 m. Research showed that the toenail of ostrich has played a vital role in producing the propulsive force in high speed locomotion. Therefore, toenail surface shape had been applied to the structure design of wheel lug of bionic walking wheel that travelled on sandy terrain by using reverse engineering technology, which finally improved the traction performance of bionic walking wheel in sandy environment. By cooperating the static column with the dynamic slide block, wheel feet have effects of sand fixation and flow limitation. At the same time, the bionic walking wheel can adaptively drive wheel lug structure into the traction working state and the non-working state of reducing sand disturbance. In order to further analyze the movement performance and properties of bionic walking wheel travelling on sand, we performed the dynamics simulation and analyzed the interaction relation between wheel foot surface and sand with the discrete element method. Using rigid multi-body dynamics, the kinetic space and interference pattern among the wheel legs of bionic walking wheel were forecasted. During the period of 1.25-2.5 s, the simulation results showed that the displacement and speed curve of slide block were relatively smooth, which indicated there was no interference in slide block structure of bionic walking mechanism and our wheel design worked effectively. At the same time, the acceleration of slide block was almost zero, which showed the impact force between slide block and stand column could be ignored in locomotion. To objectively and clearly reflect the performance of bionic walking wheel travelling on sand terrain, this study used the comparative method, and bionic wheel feet and ordinary wheel feet with the same size were adopted. Through analyzing the interactions between wheel foot and sand by discrete element method, the superior traction performance with sand fixation and flow limitation and the driving and ride comfort were verified for bionic walking wheel. The study provides the fire-new design idea of walking machine for improving the traveling performance on sand. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Wheels
Controlled terms:Animals - Biomimetics - Bionics - Birds - Computer simulation - Design - Machine design - Reverse engineering - Sand - Speed  - Traction (friction)
Uncontrolled terms:Comparative methods - Discrete element simulation - Dynamics analysis - Interference patterns - Metatarsophalangeal joints - Morphology structures - Movement performance - Traction performance
Classification code:461  Bioengineering and Biology - 483.1  Soils and Soil Mechanics - 601  Mechanical Design - 601.2  Machine Components - 723.5  Computer Applications - 931.1  Mechanics
Numerical data indexing:Size 5.00e+00m, Time 1.25e+00s to 2.50e+00s, Time 1.80e+03s, Velocity 1.39e+01m/s, Velocity 1.94e+01m/s
DOI:10.11975/j.issn.1002-6819.2016.15.004

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 42>

Accession number:20163302706394
Title:Moisture diffusion characteristics and quality characteristics of rice during drying
Authors:Xu, Fengying (1); Huang, Mushui (1); Chen, Zhen (1); Li, Changyou (1) 
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou; 510642, China 
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:261-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Traditionally, researches of rice drying methods are only focused on moisture diffusion characteristics and quality characteristics respectively. But the questions how both of those characteristics affect the multilayer structure moisture diffusion of grain, how their structure forms, and how the physiological-biochemical quality converts under high temperature thermal are ignored. Thus, the cooperative improvement mechanism of rice drying characteristics and quality is difficult to reveal. In order to study coupling characteristics among balanced efficient mechanical drying feature, moisture diffusion characteristics, microstructure, chromatic aberration, and physiological- biochemical characteristics for rice grain, this paper analyzed the relationship among moisture diffusion equations and its effective moisture diffusion coefficient, Arrhenius factor, and activation energy for short column rice grain. By methods of separately measuring and fitting, the paper investigated the dewatering characteristics of continuous drying process at 50, 65, and 80&#8451; for Yuxiangyouzhan rice, compared the effective moisture diffusivity of continuous drying at the 3 different temperatures, and studied the Arrhenius factor and activation energy. Then, the porosity and the fractal dimension of rice shell were compared under intermittent drying at 50, 65, and 80&#8451;. Furthermore, the moisture and the maximum heat flux were compared for Yuxiangyouzhan rice at different drying stages, as well as their start temperature, midpoint temperature, end temperature of glassing converting, and specific heat. Finally, the hardness, crack percentage, germination rate, and moisture content were studied for fresh rice in the interval drying process at the 3 different temperatures, as well as the heat flux, fractal dimension, hardness, and cracked germination effect. The results showed that the moisture effective diffusivity of rice grain significantly increased with drying temperature. When continuously drying at 50, 65, and 80&#8451;, the moisture effective diffusivity of rice grain was 8.92&times;10^-11, 1.04&times;10<inf>-10</inf>, 1.49&times;10^-10m²/s, respectively. Correspondingly, the moisture effective diffusion coefficient was 3.576&times;10^-8e^-15684/T m²/s. The relative chromatic aberration of rice under the 3 different temperatures similarly fluctuated during the drying process. The porosity of husk cross section of fresh rice and dried rice at the end stage of intermittent drying at 50, 65, and 80&#8451; was 0.39&plusmn;0.06, 0.22&plusmn;0.09, 0.17&plusmn;0.04 and 0.13&plusmn;0.05, respectively. When the temperature increased, the fractal dimension fluctuated, and their values were respectively equal to 1.980, 2.053, 2.046 and 2.016. Furthermore, when the temperature increased, the heat flux density of fresh rice and dried rice changed and then stayed at a stable level. Under the 3 different drying temperatures, when the moisture content of drying rice declined, the start temperature, the glass transition temperature, the final temperature increased. But the specific heat values only declined a little and were close. Finally, the hardness and crack percentage of dried rice were associated with the moisture diffusion feature and the quality of drying process. The hardness, crack percentage, germination rate and other properties were significantly different between sample groups. When drying at the temperature of 50&#8451;, its hardness and germination rate were higher than fresh rice, and its crack percentage stabilized at 2%-8.7%. In summary, drying characteristics and structural quality characteristics affected each other. Among the 3 different drying temperatures, although the dewatering performance at 50&#8451; was weak, it had a better quality characteristic, which meant that it should be preferably recommended as the conventional drying temperature for rice. The research results can provide a theoretical reference for uniform and high quality rice drying in the mechanization of rice drying. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Grain (agricultural product)
Controlled terms:Aberrations - Activation energy - Chemical activation - Cracks - Cultivation - Dewatering - Diffusion - Drying - Fractal dimension - Fractals  - Glass - Glass transition - Hardness - Heat flux - Machinery - Moisture - Moisture determination - Physiology - Porosity - Specific heat  - Temperature
Uncontrolled terms:Biochemical characteristics - Effective diffusion coefficients - Effective diffusivities - Effective moisture diffusivity - Moisture diffusion - Moisture diffusion coefficient - Quality characteristic - Rice
Classification code:461.9  Biology - 641.1  Thermodynamics - 641.2  Heat Transfer - 802.3  Chemical Operations - 804  Chemical Products Generally - 812.3  Glass - 821.3  Agricultural Methods - 821.4  Agricultural Products - 921  Mathematics - 931.2  Physical Properties of Gases, Liquids and Solids - 944.2  Moisture Measurements - 951  Materials Science
Numerical data indexing:Percentage 2.00e+00% to 8.70e+00%
DOI:10.11975/j.issn.1002-6819.2016.15.036

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.

<RECORD 43>

Accession number:20163302706377
Title:Effects of microtopography and climate on spatial distribution and irrigation capacity of ponds
Authors:Liu, Weiping (1); Zhong, Shouqin (1); Wei, Chaofu (1) 
Author affiliation:(1) College of Resources and Environment, Southwest University, Chongqing; 400715, China 
Corresponding author:Wei, Chaofu(weicf@swu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:32
Issue:15
Issue date:August 1, 2016
Publication year:2016
Pages:133-142
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The ponds play important roles in regulating water resources in the irrigation system of hilly area. In order to reveal the characteristics and influence factors of the pond and to provide a theoretical basis for small water projects, this study chose shallow-hill region (105&deg;38'-105&deg;40'E, 30&deg;08'-30&deg;10'N), low-hill region (106&deg;23'-106&deg;25'E, 30&deg;05'-30&deg;07'N) and middle-hill region (107&deg;54'-107&deg;56'E, 30&deg;45'-30&deg;46'N) as sample regions, extracted the spatial distribution and hydrological characteristics of 85 ponds located in the study area by ArcGIS software based on the topographic data and land use data on a plotting scale of 1:2000, and combined with the meteorological data ranged from 1961 to 2010, the differences and driving factors of ponds located in different microenvironments was investigated, from the perspective of water storage capacity and water resources utilization of the catchment area. The results showed: 1) The average water area (3371 m²) and landscape area ratio (171.64 m²/hm²) of ponds in shallow-hill region was much larger than that of low- hill region (1228 m²and 93.36 m²/hm²) and middle-hill region (1468 m²and 100.37 m²/hm²), but the spatial splitting index of ponds in middle-hill region (9.50) was obviously smaller than that of shallow-hill (15.48) and low-hill region (19.27). 2) The topographic index of the ponds in shallow-hill region, with an average value of 14.34, was significantly larger than that of the low-hill region (11.81) and the middle-hill region (11.35). There was remarkably positive correlation between the pond water area and topographic index in all three study region, and the pond water area exponentially changed with topographic index, but the change sensitivity was significantly different among regions. 3) The irrigation guarantee capacity increased with the increasing pond water area as a whole. Nevertheless, this capacity of the ponds was significantly different in three regions. The middle-hill region and shallow-hill region shared a similar irrigation guarantee capacity indexwhich was obviously larger than that of low-hill region. Therefore, the topographical condition of hilly area was the determinant factor for the spatial distribution of ponds. The ponds water storage capacity became larger with higher topographic index as a whole and there was an approximately exponential function relationship between them under the same hilly terrain, indicating that the topographic index was an important factor affecting the pond water storage capacity. Irrigation requirement was the main driving force to the change of pond quantity and capacity caused by agricultural activity, and hilly terrain conditions and climate factors of the catchment area could indirectly influence the crop irrigation requirement, which were the primary factors affecting the quantity and quality of the ponds. &copy; 2016, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Water resources
Controlled terms:Catchments - Climate change - Digital storage - Exponential functions - Geographic information systems - Irrigation - Lakes - Land use - Meteorology - Ponding  - Ponds - Runoff - Spatial distribution - Topography
Uncontrolled terms:Agricultural activities - Climate factors - Function relationships - Hilly areas - Hydrological characteristics - Irrigation requirements - Water resources utilizations - Water storage capacity
Classification code:403  Urban and Regional Planning and Development - 443.1  Atmospheric Properties - 444  Water Resources - 444.1  Surface Water - 454.3  Ecology and Ecosystems - 722.1  Data Storage, Equipment and Techniques - 821.3  Agricultural Methods - 903.3  Information Retrieval and Use - 921  Mathematics - 951  Materials Science
Numerical data indexing:Area 1.23e+03m2, Area 1.47e+03m2, Area 3.37e+03m2
DOI:10.11975/j.issn.1002-6819.2016.15.019

Database:Compendex
Compilation and indexing terms, Copyright 2016 Elsevier Inc.