<RECORD 1>
Accession number:20172803930312
Title:Spatial prediction of crop water requirement based on Bayesian maximum entropy and multi-source data
Authors:Wang, Jinglei (1, 2); Kang, Shaozhong (1, 3); Sun, Jingsheng (2); Chen, Zhifang (2); Song, Ni (2)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A& F University, Yangling; 712100, China; (2) Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang; 453002, China; (3) College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:Kang, Shaozhong(kangshaozhong@tom.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:99-106
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Crop water requirement is an important basic data for planning, design and management of irrigation engineering. Obtaining high-precision regional crop water requirement prediction using multi-source data and the priori knowledge has great significance for optimal allocation of regional water resources. In the paper, multisource data was integrated using the Bayesian maximum entropy (BME) method for crop water requirement prediction. A long series of crop water requirement measured and calculated by using the crop coefficients adjusted for actual measurement, were taken as the hard data. The soft data included the missing data in partial years for some stations, literature data, the Kriging interpolation data considering the main influence elements of crop water requirement, the crop water requirement data based on the principal component analysis (PCA) and geographically weighted regression (GWR) method, and the remote sensing data. For the soft data from different sources, the expression method of probability density function was put forward and the crop water requirement information from different sources was well integrated using the BME method. Hard data for the period of 1954-2013were collected from measurements from the irrigation stations in North China. Soft data for winter wheat in North China were also collected by searching literatures and the others. The results showed that spatial distribution of crop water requirement in North China was almost consistent for the hard data, hard data + Kriging soft data, hard data + GWR soft data and hard data + the soft data except for literature data. In the southern Henan had smaller crop water requirement, but the middle part (northern part of the Yellow River) of the North China was relatively high. The crop water requirement was relatively high in Shandong but low in the northeast of Hebei such as Leting, Tangshan. The results from hard data + literature soft data were slightly different from the others and the difference might be because the time periods used were different. In general, the integration accuracy of hard data + literature soft data was 9.41% lower than that based on hard data only. Hard data integrated with the other soft data could improve the integration effect. In particular, the integration accuracy of hard data + Kriging soft data, hard data + GWR soft data and hard data + the soft data except for literature data increased by 85.33%, 85.75% and 91.69%, respectively. The integration of multi-source data through considering the terrain, meteorological factors and etc, can could better reflect the spatial distribution of crop water requirements for winter wheat, and significantly improve the estimation accuracy of crop water requirement for winter wheat. The presented method provided the most important basic data for the precise management and optimization of water and soil resources in the region with sparse monitoring stations. In the paper, we need pay attention to some questions in the soft data processing. The partially missing data of some stations need amend the variance calculation results. In order to avoid the agglomeration phenomenon, the selection of interpolation data need adopt the method of random sampling, and at the same time, the distance between adjacent samplings must be limited, should not be too far or near, and 20 km was advisable. In order to avoid too big error and uncertainty, the literature data must be screened and pretreatment, otherwise, the integration effect may be affected. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Data integration
Controlled terms:Crops - Data handling - Data processing - Entropy - Forecasting - Information management - Integration - Interpolation - Irrigation - Maximum entropy methods - Principal component analysis - Probability density function - Spatial distribution - Water resources
Uncontrolled terms:Crop water requirements - Hard data - Prior information - Regression - Soft data
Classification code:444 Water Resources - 641.1 Thermodynamics - 716.1 Information Theory and Signal Processing - 723.2 Data Processing and Image Processing - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics - 922.1 Probability Theory - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 8.53e+01%, Percentage 8.58e+01%, Percentage 9.17e+01%, Percentage 9.41e+00%, Size 2.00e+04m
DOI:10.11975/j.issn.1002-6819.2017.09.013
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 2>
Accession number:20172803930308
Title:Numerical simulation and flume experiment of shape and tension force characteristics of fishing trawl
Authors:Liu, Lili (1, 2); Hu, Fuxiang (3); Wan, Rong (4, 5); Zheng, Ji (1, 2); Gao, Min (3); Zhu, Yuanyuan (3); Dong, Shuchuang (3)
Author affiliation:(1) College of Fishery, Zhejiang Ocean University, Zhoushan; 316004, China; (2) Key Laboratory of Marine Fishery Equipment and Technology of Zhejiang, Zhoushan; 316004, China; (3) Tokyo University of Marine Science and Technology, Tokyo; 1080075, Japan; (4) National Engineering Research Center for Fishing, Shanghai; 201306, China; (5) College of Marin Sciences, Shanghai Ocean University, Shanghai; 201306, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:69-75
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Trawls are funnel-shaped nets that are towed by vessels along different water column. According to different fishing requirement and species behaviors, numerous variations for trawls exist. The performance efficiency and fuel efficiency of trawl are largely influenced by designing, which has direct affinity with net mouth opening, net body shape, netting elongation and twine distribution. Comparing with flume tank tests, the numerical model is more convenient to carry out, and also can easily obtain the tension distribution of mesh bars which otherwise is difficult to measure in water tank experiment. In order to know the shape and tension variation characteristics of trawl, in this study, a nonlinear mixed method was used to determine the equilibrium configuration and tension distribution of a trawl set in a uniform current. The method was based on finite element formulation, and the mesh bars were modeled as straight mesh bar elements which were connected with other elements by a frictionless hinge. Meanwhile, an experimental trawl model for measuring hydrodynamic characteristics was also generated, which took a kind of Japan four-seam mid-water trawl as an example. The model of trawl was made of PA (Polyamide). Measuring speed of current was set between 0.4 to 0.9 m/s. In the experiment, the photos from side view and vertical view were synchronously taken in each current velocity. Besides, the width and height of net mouth, the length of trawl body, and the tension force of leg line were all measured. Then, the corresponding simulation model of the trawl was established and solved using MATLAB based on the mathematical model with the number of mesh bar elements of 2 852 and the number of the knots of 1 399. By comparing the calculation results with measured values from circulating water tank model test, it showed that both of the leg line tension and shape of trawl generally agreed well. The tension distributions of mesh bars of trawl were also presented. The results of shape and tension variation characteristics of trawl were concluded as follows: 1) The drag force of leg line increased by power with the increase of current velocity. Average error between calculation and experimental results was about 10%. As the velocity increased, the angle of same-side upper and lower legs gradually decreased, net body length prolonged, height of net mouth narrowed corresponding with the widening of net mouth. The numerical values of width of net mouth were a little higher than experiment results, but the average error of which was within 10%. 2) The position of float line was behind sinker line in x-axis because of the flow effect, but the distance from each other diminished if current velocity increased. The effect of current velocity to shape change of trawl weakened if current velocity had been comparatively large. 3) The tension of float line, sinker line, lace rope and its surrounding mesh bars were comparatively high, while the force of cod end were small. As increase of the current velocity, the tension of most meshes of net body was increased. Moreover, the tension of up and bottom panels of trawl were larger than left and right panels. 4) Tensions of cod-end were much smaller than other parts. The force on cod-end would be mainly from the weight of catch. 5) Numerical calculation can provide quantitative theory for reasonable twine distribution of trawl. However, owing to the difference of tension distribution caused by different design of each types of trawl, it was difficult to obtain a unified standard among all of the trawls for the twine distribution problem. The mathematical method in this study can be used to effectively simulate the operating status of trawls, which included shape and tension force characteristics. Our results can provide reference for design and improvement of trawl. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Fisheries
Controlled terms:Computer simulation - Drag - Efficiency - Experiments - Finite element method - MATLAB - Mesh generation - Models - Numerical models - Tanks (containers) - Twine - Velocity - Water tanks
Uncontrolled terms:Equilibrium configuration - Finite element formulations - Hydrodynamic characteristics - Performance efficiency - Shape - Tension - Trawl - Water tank experiments
Classification code:619.2 Tanks - 694.2 Packaging Materials - 723.5 Computer Applications - 901.3 Engineering Research - 913.1 Production Engineering - 921 Mathematics - 921.6 Numerical Methods
Numerical data indexing:Percentage 1.00e+01%, Velocity 4.00e-01m/s to 9.00e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.09.009
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 3>
Accession number:20172803930325
Title:Research on matrix formula of substrate for seedling in rice closed stereo seedling system
Authors:Zhao, Lijun (1, 2); Chen, Haitao (1); Cai, Xiaohua (2); Xu, Chunlin (1); Li, Qiang (1); Wang, Jinfeng (1); He, Di (1)
Author affiliation:(1) College of Engineering, Northeast Agriculture University, Harbin; 150030, China; (2) Heilongjiang Province Agriculture Machinery Engineering Scientific Academy, Harbin; 150081, China
Corresponding author:He, Di(hedi04511558@souhu.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:204-210
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Greenhouse seedling is the valuable mode to solve the problem of insufficient accumulated temperature for the rice production to realize the stable and high yield in Heilongjiang Province, China. However, the shortage of soil resources limits the application of seedlings field. Vegetation degradation and costly manpower are unfavorable for the protection of soil resources. Therefore, development of seedlings substrate to replace the soil is an effective way to solve these problems. Closed stereo seedlings of rice is a new way to improve the rice seedling, which may realize the automatic control of the environment to meet the requirement of the growth of seedlings in a relatively enclosed environment including temperature, humidity, light, CO<inf>2</inf>concentration and nutrient solution. Natural conditions have little effect on the rice seedling growth in these enclosed environments. This seedling style has advantages of high space utilization, less dosage of field soil and strong adaptability, which helps to cope with frequent extreme weather and cold ground and cover a big area. Seedling substrate of closed stereo rice comes from the agricultural waste materials. It can not only avoid the destruction of farmland and reduce the transportation cost, but also solve the environmental pollution problem caused by the burning of agricultural waste to promote the development of circular agriculture. In this study, corn straw and rice husk were selected as grinding material and blended with perlite and field soil at different volume ratio. Seedling tests were carried out with 3 kinds of single substrate i.e. CK1 (100% field soil), CK2 (100% crushed corn stalks), and CK3 (100% crushed rice husk) and 6 kinds of composite matrix i.e. S1 (80% crushed rice husk + 10% field soil + 10% perlite), S2 (60% crushed rice husk + 20% field soil + 20% perlite), S3 (40% crushed rice husk + 40% field soil + 20% perlite), T1 (80% crushed corn stalks + 10% field soil + 10% perlite), T2 (60% crushed corn stalks + 20% field soil + 20% perlite), and T3 (40% corn stalks + 40% field soil + 20% perlite). The results showed that there were significant differences on bulk density, total porosity, pH value (except S3), organic matter content (except S2), and nutritive element content between CK1 and the other 8 treatments (P<0.05). The later seedling stage showed that compared to the field soil (CK1), the comprehensive quality of seedlings under other 8 matrix treatments was higher. Composite matrix with the addition of the crushed rice husk (S1, S2, S3) and crushed corn straw (T1, T2, T3) had more significant improvement to seedling growth than single matrix (CK1, CK2, CK3). Composite matrix with corn straw (T1, T2, T3) had higher effect than rice hull (S1, S3). Amount of rice husk and corn straw had significant effect on the seedling growth. Each characteristic of the seedling was the optimal when the addition amount of rice husk or corn straw was 60% (S2 and T2), while no significant difference was found for the other 2 treatments (P<0.05). Eventually, T2 treatment with corn straw of 60%, field soil of 20%, and perlite of 20% had the optimal result in terms of seedling agronomic index, biomass index and mechanical properties. Based on the results from the field experiment, rice yield characteristics in the mature period were analyzed in the different light source, substrate and method of raising seedling. The results showed that the light source, substrate and ways of raising seedlings had significant effect on the rice yield. Under the different conditions of substrate and method of raising seedling, the T treatment (with closed stereo, LED (light emitting diode) fluorescent lamp, T2 substrate) had lower average plant height and thousand seed weight compared with the CK treatment, while tiller number had no obvious difference. The other 5 indicators were higher than the CK. Real yield was 5.9% higher than that of CK. The results provide efficient and stable production technical basis for the closed stereo rice seedling system. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Soil testing
Controlled terms:Agricultural wastes - Agriculture - Automation - Humidity control - Light emitting diodes - Light sources - Matrix algebra - Nutrients - Physical properties - Problem solving - Seed - Soils - Substrates
Uncontrolled terms:Accumulated temperatures - Closed type - Comprehensive qualities - Environmental pollution problem - Organic matter content - Rice - Rice husk - Seedling
Classification code:483.1 Soils and Soil Mechanics - 714.2 Semiconductor Devices and Integrated Circuits - 731 Automatic Control Principles and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.1 Algebra - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.00e+02%, Percentage 2.00e+01%, Percentage 4.00e+01%, Percentage 5.90e+00%, Percentage 6.00e+01%, Percentage 8.00e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.026
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 4>
Accession number:20172803930338
Title:Sorting of peeled mandarin segments with orange core based on characteristic fluorescent signal
Authors:Wang, Yequn (1); Yang, Zengling (1); Ren, Weidong (2); Liu, Ting (1); Yang, Jie (1); Zhang, Shaoying (1)
Author affiliation:(1) College of Engineering, China Agriculture University, Beijing; 100083, China; (2) Huichuanshengye Technologies Co. Ltd, Beijing; 100176, China
Corresponding author:Zhang, Shaoying(cauzsy@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:296-301
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The peeled mandarin segment with orange core (central column residue) is one kind of defective mandarin segment during the production of canned mandarin. So it is necessary to remove the defective mandarin segments according to the requirement of quality before canning. Due to the differences of physical and chemical properties between orange core and orange gizzard, the fluorescence spectra of orange core and orange gizzard are different theoretically. For the purpose of offering direct and accurate signals to the machine to identify the peeled mandarin segments with orange cores, in this study, the peeled mandarin segments were taken as the samples, and the 3D (three-dimensional) fluorescence spectra of orange core and orange gizzard were determined by Cary Eclipse fluorescent spectrophotometer (excitation wavelength in the range of 250-700 nm, 5 nm interval; emission wavelength in the range of 300-800 nm, 1 nm interval; discharge voltage of 600 V, scanning speed of 1 200 nm/min). The differences of fluorescence characteristics of orange core and orange gizzard were found according to the 3D fluorescence spectra after removing Rayleigh and Raman scatter. In order to verify the differences further, the fluorescence spectra of orange core and orange gizzard of 50 peeled mandarin segments were determined by Cary Eclipse fluorescent spectrophotometer (at an excitation wavelength of 370 nm, an emission wavelength in the range of 400-700 nm with the interval of 1 nm, a discharge voltage of 600 V, a scanning speed of 1 200 nm/min). The differences of fluorescence intensities at 440 nm for orange core and orange gizzard were evaluated by means of drawing the box-plots of the fluorescence intensity at 440 nm. The accuracy rate of the discrimination of orange core and orange gizzard was analyzed, and the average value between fluorescence intensity of orange core at the lower quartile and that of orange gizzard at the upper quartile at 440 nm was used as classification criterion. The camera obscura was taken as a platform, and 2 sets of ultraviolet light sources with center wavelength of (370±2 nm) were selected as imaging light sources. The fluorescence images of the mandarin segments with and without orange core were taken using a monochrome fluorescence image acquisition system, which was set up by putting a band-pass filter (440±5 nm) in the front of Image soft G445 camera objective. The grayscale images were obtained by extracting B color component from RGB images, and then the binary images were generated by applying the threshold values, with the IN Vision Assistant software. The results showed that there were significant differences between orange core and orange gizzard of peeled mandarin segments at an excitation wavelength of 370-390 nm and an emission wavelength of 440 nm. According to the classification criterion the discrimination accuracy of orange core and orange gizzard was 85%. Meanwhile, using the fluorescence image acquisition system, the monochrome images of the mandarin segments with and without orange core were obtained respectively. There was significant difference between them, and thus the mandarin segments with orange core and the mandarin segments without orange core could be distinguished effectively. Overall, the study indicates that the fluorescence signal at an excitation wavelength of 370-390 nm and an emission wavelength of 440 nm can be the exclusive light signal of the orange core for on-line, nondestructive sorting, which is help to eliminate the peeled mandarin segments with orange core. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Citrus fruits
Controlled terms:Binary images - Cameras - Fluorescence - Image acquisition - Image processing - Light sources - Meteorological instruments - Sorting - Spectrophotometers
Uncontrolled terms:Fluorescence characteristics - Fluorescence intensities - Orange core - Orange gizzard - Peeled mandarin segments - Physical and chemical properties - Spectrum - Ultraviolet light sources
Classification code:443.2 Meteorological Instrumentation - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 741.1 Light/Optics - 741.3 Optical Devices and Systems - 742.2 Photographic Equipment - 821.4 Agricultural Products
Numerical data indexing:Percentage 8.50e+01%, Size 1.00e-09m, Size 2.50e-07m to 7.00e-07m, Size 3.00e-07m to 8.00e-07m, Size 3.70e-07m, Size 3.70e-07m to 3.90e-07m, Size 4.00e-07m to 7.00e-07m, Size 4.40e-07m, Size 5.00e-09m, Voltage 6.00e+02V
DOI:10.11975/j.issn.1002-6819.2017.09.039
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 5>
Accession number:20172803930331
Title:Experiment of integrated fermentation hydrogen production by photosynthetic bacteria cooperating with Enterobacter aerogenes
Authors:Zhang, Quanguo (1, 2); Zhang, Tian (1); Zhang, Zhiping (1, 2); Zhou, Xuehua (1, 2); Wang, Yi (1); He, Chao (1, 2)
Author affiliation:(1) Key Laboratory of New Materials and Facilities for Rural Renewable Energy (MOA), Henan Agricultural University, Zhengzhou; 450002, China; (2) Collaborative Innovation Center of Biomass Energy, Zhengzhou; Henan Province; 450002, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:243-249
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Along with the rapid development of society and unceasing improvement of human living standard, the consumption of fossil fuels is rising continuously, which has resulted in several problems such as energy shortage and environmental pollution. Therefore, the research and exploitation of renewable energy become extremely urgent. Hydrogen is a promising alternative energy, and can be produced through different methods. Considering the complementarity between different hydrogen-production microorganisms, dark-photo integrated bio-hydrogen production was regarded as a beneficial way to improve the utilization rate of substrate and the potential of hydrogen production. Dark-photo integrated bio-hydrogen production could combine the characteristics of various microbes, and exert their advantages. Moreover, enzymatic hydrolysis of complex substrate, VFAs production, VFAs consumption, and hydrogen production could synchronously take place, so it could realize the reuse of byproducts (VFAs) and avoid the accumulation of liquid byproducts. In this study, enzymatic hydrolyzate of corn stover was taken as substrate, Enterobacter aerogenes (AS1.489) and photosynthetic bacteria (HAU-M1) were selected as hydrogen-production microorganisms, and simultaneous saccharification fermentative method was adopted to study the process of dark-photo integrated bio-hydrogen production by mixed cultivation of HAU-M1 and Enterobacter aerogenes. Cumulative hydrogen yield was taken as key reference to optimize the process parameters of bio-hydrogen production. The single factor experiments were adopted to select the optimal lever and analyze the effects of substrate concentration, initial pH value, light intensity and fermentation temperature on the integrated bio-hydrogen production. On the basis of single factor experiments, orthogonal experimental design was also adopted to further optimize the bio-hydrogen production process parameters and evaluate the significance of influencing factors. The results of orthogonal range analysis showed that primary and secondary order of the influence of various process parameters on integrated bio-hydrogen production was: fermentation temperature>initial pH value>substrate concentration>light intensity. The analysis of variance showed that fermentation temperature and initial pH value were the most significant factors affecting integrated bio-hydrogen production and produced the most significant influence on the process of integrated bio-hydrogen production by mixed cultivation of photosynthetic bacteria and Enterobacter aerogenes. The optimum process parameters were: substrate concentration of 35 g/L, initial pH value of 6.5, light intensity of 3 500 lx, and fermentation temperature of 30℃. The validation experiments under these conditions were performed, and the cumulative hydrogen yield of 332.6 mL for 72 h and the capacity of unit hydrogen production of 47.5 mL/g corn stover were obtained. The optimal process parameters for bio-hydrogen production provide a scientific reference for the further research on integrated bio-hydrogen production by mixed cultivation of dark-fermentative and photo-fermentative bacteria from straw biomass. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Hydrogen production
Controlled terms:Bacteria - Byproducts - Design of experiments - Enzymatic hydrolysis - Fermentation - Hydrogen - Image processing - Microorganisms - pH - Saccharification - Substrates
Uncontrolled terms:Bio-hydrogen production - Enterobacter aerogenes - Mircroorganism - Mixed cultivations - Photosynthetic bacterias
Classification code:461.9 Biology - 522 Gas Fuels - 801.1 Chemistry, General - 802.2 Chemical Reactions - 804 Chemical Products Generally - 901.3 Engineering Research
Numerical data indexing:Illuminance 3.50e+03lx, Mass_Density 3.50e+01kg/m3, Specific_Volume 4.75e-02m3/kg, Time 2.59e+05s, Volume 3.33e-04m3
DOI:10.11975/j.issn.1002-6819.2017.09.032
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 6>
Accession number:20172803930319
Title:Research progress and prospect on combining crop growth models with parameters derived from quantitative remote sensing
Authors:Wu, Lei (1, 2); Bai, Junhua (1, 3); Xiao, Qing (1, 3); Du, Yongming (1, 3); Liu, Qinhuo (1, 3); Xu, Liping (2)
Author affiliation:(1) Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences, Beijing; 100101, China; (2) Shihezi University, Shihezi; 832000, China; (3) State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth Chinese Academy of Sciences, Beijing; 100101, China
Corresponding author:Bai, Junhua(bjh0902@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:155-166
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Combining the crop growth models with the remote sensing parameters, is important to realize the applications in the large spatial scale for the former, and also to improve the rationality and accuracy of inversion theory for the latter. Some research fields, such as the ecology, agriculture, resource investigation and global climate change, would use the data derived from the combination form. The overview includes 3 parts, i.e. the international crop growth model, the quantitative remote sensing parameters and the parametric methods. From the view of the spatial expansion for the application of the crop growth model, the development duration of crop growth models was divided into 3 stages: The construction of the mechanism models, the application in the point scale, and the application in the regional and global scale. In order to understand the situation and foundation of the inter-discipline combination from the crop growth simulation and the quantitative remote sensing, the paper describes 3 important contents. The first is overviewing the main simulation processes and the input and output parameters for the typical crop growth models. The second is summarizing the remote sensing inversion parameters which can be used as the initialization and driving data for the application of crop growth simulation models in the regional and global scale, establishing the corresponding relation between the simulation process of crop growth model and the parameters from the quantitative remote sensing. And the third is comparing 3 kinds of combination methods between the crop growth model and the parameters derived from the quantitative remote sensing, and emphasizing the differences, advantages and disadvantages for the 3 combination methods. Based on the contents mentioned above, 3 topics for discussion are proposed. The first topic is the application limitations of crop growth models in the large spatial scale and its relationship with quantitative remote sensing parameters. The second one is the influence of the scale effect from the input parameters when the crop growth model is used to simulate the crop growth in the larger region. And the third one is to discuss the development direction of combination methods. It is hopeful to provide a kind of thinking for combining the crop growth models with the parameters from the quantitative remote sensing through the overview, summary and discussion. And it is clearly concluded that the data from the quantitative remote sensing can provide initialization data for crop growth models to some extent in the regional and global scale, and the application in a large space scale is the direction of crop growth model. The conclusion shows further that it is important to pay attention to the scale problem of the model parameters, and that the data dis-matching for the same parameter from the crop growth and remote sensing can result in the huge error of estimation on the output data due to the difference of physical meaning from the 2 disciplines. Understanding that the data from the quantitative remote sensing could enhance the ability of simulating the crop conditions and yield at the large scale was also helpful to understand that the remote sensing had the ability of deriving the biochemical and biophysical information from the ground surface exactly. And furthermore, it is expected that the correct combination parameters should be chosen to deduce the propagation of error and uncertainty, the assimilation methods would still preserve the mainstream style for the combination, and following the increasing accuracy of data from the remote sensing and crop model, the fusion model for the model of crop growth and remote sensing can be constructed to play a greater application value in the environmental monitoring and agricultural production. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:94
Main heading:Crops
Controlled terms:Agriculture - Climate change - Models - Remote sensing - Space optics - Vegetation
Uncontrolled terms:Agricultural productions - Biophysical information - Combination - Corresponding relations - Crop growth - Development - Environmental Monitoring - Quantitative remote sensing
Classification code:443.1 Atmospheric Properties - 656.1 Space Flight - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products
DOI:10.11975/j.issn.1002-6819.2017.09.020
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 7>
Accession number:20172803930315
Title:Black-soil paddy field experiment on improving soil physical and chemical properties and increasing rice yield by continuous deep ploughing
Authors:Wang, Qiuju (1); Gao, Zhongchao (1); Zhang, Jinsong (1); Chang, Benchao (1); Jiang, Hui (2); Sun, Bing (3); Guo, Zhongyuan (4); Jia, Huibin (5); Jiao, Feng (6); Liu, Feng (2)
Author affiliation:(1) Institute of Soil Fertilizer and Environment Resources, Heilongjiang Academy of Agricultural Sciences, Harbin; 150086, China; (2) Management Department of Scientific Research of Heilongjiang Academy of Agricultural Sciences, Harbin; 150086, China; (3) Institute of Tillage and Cultivation, Heilongjiang Academy of Agricultural Sciences, Harbin; 150086, China; (4) Irrigation Experimental Establishment of Heilongjiang, Qingan; 152400, China; (5) Jiamusi Branch Academy of Heilongjiang Academy of Agricultural Sciences, Jiamusi; 154007, China; (6) Heilongjiang Bayi Agriculture University, Daqing; 163319, China
Corresponding author:Liu, Feng(liufengjms@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:126-132
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rice is cultivated in large area in Heilongjiang Province. The area of rice cultivation in Heilongjiang is about 100 thousand hectares. For a long time, rotary or shallow ploughing is the main tillage mode of paddy soil. Rotary tillage depth is usually 8-10 cm, and shallow ploughing is 12-13 cm. Long term shallow ploughing has the following problems. First, it makes plough pan layer move upward, which leads to the shallower tillage layer and the rise of the plow bottom. With the reduction of effective space for roots growth, roots cannot absorb nutrients from deep soil and the soil nutrient supply per unit area will decrease. Second, it easily leads to rice lodging in late growth stage due to the shallow rooting zone. When the roots are hindered by the plough pan layer, they cannot grow vertically and only extend horizontally, which results in a decrease in the ability to support stems. The more roots in the deep soil, the stronger the ability of roots to fix the soil, and the stronger lodging resistance. Shallow ploughing leads to a decrease in the soil nutrient supply per unit area. In order to meet the growth of crops, a large amount of fertilizers have to be applied, especially nitrogen, which can cause late maturing rice, lodging and losses in yield. Third, soil aeration and water permeability are impeded by the plow bottom, the air in the upper and lower soil layers is not in circulation. As long as the soil is in the reduction state, it is easy to form reduced iron, manganese as well as reduced gases such as H<inf>2</inf>S, which results in rice roots poisoning and a reduction of yield. The results of the survey for rice cultivation in Heilongjiang area showed that the topsoil thickness of high-yield cropland soil is generally 15-17 cm, and the plough layer thickness is 7-8 cm. the medium-yield cropland soil is generally 12-15 cm and 8-10 cm, and low-yield is 8-10 cm and greater than 8-10 cm, respectively. In Honghe farm, long term production practice concluded that the yield of 20 cm deep ploughing was 10% higher than that of 8-10 cm. In order to clarify the effects of deep ploughing on soil physical and chemical properties and rice yield, in this paper, we carried out the research of large area contrast of deep tillage, shallow tillage and rotary tillage by use of the independent developed deep plough of paddy field. The results showed that shallow and deep ploughing can reduce soil solid ratio and bulk density. The soil solid phase ratio was 0.74%-4.80% and 1.86%-3.90% lower than rotary tillage respectively. The soil bulk density respectively decreased by 0.09 g/cm<sup>3</sup>and 0.08 g/cm<sup>3</sup>in the 10-20 cm soil layer. The soil bulk density of deep ploughing was decreased by 0.03 g/cm<sup>3</sup>than that of rotary tillage in the 20-30 cm soil layer. Compared with rotary tillage, the soil permeability coefficient and saturated permeability coefficient of shallow ploughing were increased by 4.04 and 2.71 times in the 10-20 cm soil layer, respectively, those of deep ploughing were 4.42 and 2.14 times, and those of deep ploughing were 1.86 and 2.87 times in the 20-30 cm soil layer. In two years, the change trend of soil aeration coefficient and saturated permeability coefficient was consistent. Deep ploughing can promote the growth of rice roots. The increase of root growth amount and length was 6.53%-16.33% and 10.81%-21.62%, respectively, and deep ploughing is better than shallow. Deep ploughing increases the yield of rice. In 2015, shallow and deep ploughing in rice yield increased by 6.91% and 9.81%, respectively compared with rotary tillage, and by 6.59% and 7.84% in 2016. The trend of increasing yield was consistent in two years. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:22
Main heading:Soil surveys
Controlled terms:Agricultural machinery - Agriculture - Biological materials - Chemical properties - Cultivation - Nitrogen fertilizers - Nutrients - Soils - Water aeration
Uncontrolled terms:Deep ploughing - Nutrient accumulation - Physical and chemical properties - Root - Yield
Classification code:445.1 Water Treatment Techniques - 461.2 Biological Materials and Tissue Engineering - 483.1 Soils and Soil Mechanics - 801 Chemistry - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Mass_Density 3.00e+01kg/m3, Mass_Density 8.00e+01kg/m3, Mass_Density 9.00e+01kg/m3, Percentage 1.00e+01%, Percentage 1.08e+01% to 2.16e+01%, Percentage 1.86e+00% to 3.90e+00%, Percentage 6.53e+00% to 1.63e+01%, Percentage 6.59e+00%, Percentage 6.91e+00%, Percentage 7.40e-01% to 4.80e+00%, Percentage 7.84e+00%, Percentage 9.81e+00%, Size 1.00e-01m to 2.00e-01m, Size 1.20e-01m to 1.30e-01m, Size 1.20e-01m to 1.50e-01m, Size 1.50e-01m to 1.70e-01m, Size 2.00e-01m, Size 2.00e-01m to 3.00e-01m, Size 7.00e-02m to 8.00e-02m, Size 8.00e-02m to 1.00e-01m
DOI:10.11975/j.issn.1002-6819.2017.09.016
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 8>
Accession number:20172803930307
Title:Analysis and test of dynamic characteristics of large spraying boom and pendulum suspension damping system
Authors:Cui, Longfei (1, 2); Xue, Xinyu (1); Ding, Suming (1); Qiao, Baiyu (1); Le, Feixiang (1)
Author affiliation:(1) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture, Nanjing; 210014, China; (2) Institute of Agricultural Engineering, Jiangsu University, Zhenjiang; 212013, China
Corresponding author:Xue, Xinyu(735178312@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:61-68
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To increase the yield in agriculture, plants must be protected against diseases and need to be provided with fertilizers. One of the most important methods to spread agro-chemicals is by using spray booms. The efficiency of the chemicals is highly correlated with the uniformity of the spray distribution pattern, and as spray boom motions play a dominant role on the spray distribution pattern, spray boom stability is important. Moreover, with the stable boom, the distance between the nozzles and the target can be reduced, and then the drift losses are less important. Boom movements are due to ground irregularities that are transformed and more or less amplified depending on the mechanics features of the boom suspension. In order to reduce the unevenness in spray deposit, the majority of current agricultural sprayers are equipped with a suspension system to attenuate the roll of the boom. The suspension tries to keep the boom at right angles by isolating the boom from vibrations of the tractor or trailer which are induced by unevenness of the ground. Therefore, the suspension system should act as a system that attenuates undesired machine movement. The most important vibration, affecting the spray distribution pattern, is rolling (rotational motion around an axis along the driving direction) that causes spray boom motions in the vertical plane. However, the correlation between the dynamic behavior of the spray boom and suspension parameters are still unclear and the design principles and methods of the pendulum boom suspension are also missing or imperfect, which restrict the improvement of spray quality and operation efficiency. In order to understand the effect of the dynamic parameters of pendulum suspension system on the dynamic behavior of the spray boom, an analytical mathematical model of this pendulum suspension is established by using the second kind of Lagrange equations and the necessary transfer function. The dynamic characteristics of the pendulum suspension are derived, and the behavior such as the rolling movement and vertical movement of the passive suspension can be most conveniently described by its complex frequency response function. Transient response analysis and frequency response analysis are carried out in MATLAB/Simulink, and the effects of dynamic parameters on the characteristics of the suspension are studied. On the basis of this, taking a large spray boom and its pendulum suspension as the test object, the boom rolling movement and vertical movement excitations were outputted by using the six degrees of freedom motion simulation platform, and the boom suspension was instrumented with ultrasonic distance sensor, LVDT (linear variable differential transformer) displacement sensor, and so on. The transient dynamic response and frequency response characteristics of spray boom were measured, and then the accuracy of the mathematical model was verified. The root mean square error between the mathematical model predictive value and test value was 0.146 for rolling frequency response, and 0.203 for vertical oscillation frequency response. Peak value of the amplitude frequency curve and the corresponding frequency were determined by the sweep frequency vibration test, and the influence of damping and stiffness coefficients on the vibration characteristics of the boom was analyzed. In a certain range, increasing the damping could reduce the system oscillation and increase the stiffness, which was beneficial to increase the response speed and natural frequency of the suspension, but natural frequency could not be too high since beyond this frequency the suspension started to suppress the disturbances. Through research, we get to know that this kind of pendulum suspension with springs and dampers can enable the boom to follow low frequency ground undulations so remaining parallel to the ground beneath it, while providing isolation from the rapid motion of the spray vehicle as it travels over rough terrain. This study also provides a theoretical basis and test method for the parameters configuration of large boom, and it is beneficial to perfect the test method and test standard of the dynamic characteristics of large scale spraying boom (over 12 m) in China. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Suspensions (components)
Controlled terms:Agricultural machinery - Agriculture - Damping - Efficiency - Electric transformer testing - Equations of motion - Experiments - Frequency response - Functions - Machinery - Magnetic levitation vehicles - Mean square error - Mechanization - Models - Natural frequencies - Pendulums - Stiffness - Testing - Vibration analysis
Uncontrolled terms:Boom sprayer - Dynamic characteristics - Frequency response characteristic - Linear variable differential transformer - Pendulum suspensions - Spray booms - Spray distribution patterns - Transient response analysis
Classification code:601 Mechanical Design - 601.2 Machine Components - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 913.1 Production Engineering - 921 Mathematics - 921.2 Calculus - 922.2 Mathematical Statistics - 931.1 Mechanics - 951 Materials Science
Numerical data indexing:Size 1.20e+01m
DOI:10.11975/j.issn.1002-6819.2017.09.008
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 9>
Accession number:20172803930301
Title:Design and experiment of 1MCDS-100A typed shovel-sieve residual film recovery machine
Authors:You, Zhaoyan (1); Hu, Zhichao (1); Wu, Huichang (1); Zhang, Yaping (1); Yan, Jianchun (1); Yan, Wei (1); Zhou, Xinxing (1)
Author affiliation:(1) Nanjing Research Institute of Agricultural Mechanization, Ministry of Agriculture, Nanjing; 210014, China
Corresponding author:Hu, Zhichao(nfzhongzi@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:10-18
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plastic mulching planting pattern is usually adopted when planting peanut, cotton and other crops in modern agriculture, and the planting soil type is mostly in sandy soil or sandy loam with good fragility. As more and more residual membrane left in the field surface, accumulation of the residual film which is not clearly picked up all the year round, causing serious "white pollution". Taking typical croplands in North China for example, it is estimated that, the quantity of residual film in peanut and cotton fields would reach up to 69.1 and 70.4 kg/hm<sup>2</sup>by 2021, If we do not pay attention to the recovery of residual film, these areas would become the pollution area contaminated by residual plastic membrane. In order to solve serious pollution of residual plastic film left in the field after harvest, several residual film recovery machines are commonly used, such as tooth type (spike tooth, elastic claw, telescopic tooth, etc.), curl-up film roller type, shovel-chain type, and multi-function duplex machinery, but both domestic and international shovel-sieve type residual film recovery machines which adapt to sandy soil have been rarely reported. First, the current sieving surface had no structural design of blocking glide in the process of screening, while film, soil and impurity substance could easily cause soil accumulation because of its own gravity, leading to the clogging of sieve holes with low membrane separation efficiency. Second, the step by step transmission ability of vibration sieve was poor, causing residual film winding, membrane leakage, reversing and other issues. In addition, most of the existing shovel-screen type residual film recycling machines had only one single sieve. As such cleanliness of recycled residual film needs to be improved. At the same time, in order to reduce vibration, the existing eccentric drive arm equipment was often equipped with rotary parts when screening, such as the eccentric block, flywheel or other parts, but rotary motion of chosen rotary parts could not eliminate the reciprocating movement of sieve, causing large vibration in the process of machine operation, high labor intensity of drivers and poor stability of machinery. In order to reduce vibration in the operation of shovel-sieve type residual film recycling machine, in this study, a up and down parallel arranged double-sieve type self-balancing residual film recycling machine was designed, rotation speed of drive shaft was determined, ranging from 260 to 330 r/min, a DH5902 dynamic testing system was used. A field experiment was carried out to test the vibration parameters of the double-sieve residual film recycling machine and the experimental results showed that vibration frequency from 3 to 5.5 Hz, horizon vibration measurement value of the frame was 4.2-5.4 m/s<sup>2</sup>, among which the equipment could withstand, the damping effect of double-sieve residual film recycling machine was obvious, five sieves with different sieve surface structures including the bar sieve, cross bar sieve, wire gauze sieve, round hole sieve and saw-tooth sieve were tested by single factor experiment. Finally, saw-tooth sieve was determined as the optimal sieve form. Moreover, an electric pushing rod typed automatic film uploading device was designed, film collecting basket completed the unloading task in 4.1 s, solving longtime labor issues currently exist in uploading link. Machine forward speed, vibration frequency of saw-tooth sieve, amplitude of saw-tooth sieve and saw-tooth distance were selected as experiment factors. The response surface method was used, and the effect of each factor influenced on the targets of the residual film recycling was analyzed by drawing four-dimensional chip figure on Matlab2013a software. The experimental results showed that the test factors had a great influence on residual film recovery quality. The optimal parameter combination was obtained: machine forward speed was 0.73 m/s, amplitude of saw-tooth sieve was 99 mm, vibration frequency of saw-tooth sieve was 280 r/min, saw-tooth distance was 12 mm, when the recovery rate of residual film was 91.26%, rate of winded film was 4.27% and film soil ratio was 2.16. It met the requirements of the residual film recycling quality. This study not only supplies the residual film recycling market with a both urgent and practical tool, but also provides theoretical basis and reference for the innovation development and optimization of plastic film recovery machinery. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Sieves
Controlled terms:Agricultural machinery - Agriculture - Cotton - Design - Electric windings - Machine design - Membranes - Oilseeds - Plastic films - Plastic recycling - Pollution - Recovery - Recycling - Sand - Saws - Shovels - Soil pollution - Soils - Structural design - Unloading - Vibration control - Vibrations (mechanical)
Uncontrolled terms:Drive mechanism - Membrane separation - Modern agricultures - Optimal parameter combinations - Residual films - Response surface method - Single-factor experiments - Vibration parameters
Classification code:408.1 Structural Design, General - 452.3 Industrial Wastes - 483.1 Soils and Soil Mechanics - 601 Mechanical Design - 691.2 Materials Handling Methods - 731.3 Specific Variables Control - 817.1 Polymer Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics - 951 Materials Science
Numerical data indexing:Acceleration 4.20e+00m/s2 to 5.40e+00m/s2, Frequency 3.00e+00Hz to 5.50e+00Hz, Percentage 4.27e+00%, Percentage 9.13e+01%, Rotational_Speed 2.60e+02RPM to 3.30e+02RPM, Rotational_Speed 2.80e+02RPM, Size 1.20e-02m, Size 9.90e-02m, Time 4.10e+00s, Velocity 7.30e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.09.002
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 10>
Accession number:20172803930339
Title:Rapid identification of producing area of coffee bean based on terahertz spectroscopy and support vector machine
Authors:Hu, Xiaohua (1); Liu, Wei (2, 3); Liu, Changhong (3); Qian, Yunhui (3)
Author affiliation:(1) School of Computer and Information, Hefei University of Technology, Hefei; 230009, China; (2) Intelligent Control and Compute Vision Lab, Hefei University, Hefei; 230009, China; (3) School of Food Science and Engineering, Hefei University of Technology, Hefei; 230009, China
Corresponding author:Liu, Wei(lwei1524@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:302-307
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Coffee is a very popular beverage in many countries. Coffee bean from different producing area has different flavour and functional properties, and thus the identification of producing area of coffee bean is important to assure the quality of coffee bean. The feasibility of a rapid and precise determination method of producing area of coffee bean was examined by using the terahertz (THz) time-domain spectra system (TAS7500TS HF1, Advantest Co., Ltd, Japan). Coffee bean samples from 3 different typical producing areas (Ethiopia, Costa Rica, and Indonesia) were collected and pressed into pellets for THz measurements. A total of 180 pellet samples (3 classes, each had 60 pellet samples) were randomly divided into calibration set (40 pellet samples for each class) and prediction set (20 pellet samples for each class). THz time-domain spectroscopy system worked with the TAS7500TS equipment in transmission mode. Before the experiment, the dry air was injected until the relative humidity reached below 3% to reduce the absorption of the THz waves by water in air. The parameters of THz system were as follow: frequency range was from 0.1 to 4 THz, the resolution was 7.6 GHz, the short pulse width was less than 50 fs and the average power was 20 mW. For each sample, the THz time-domain spectra were measured for 3 times at different position and then the average values were obtained. The frequency-domain spectra were acquired by a fast Fourier transform (FFT). Principal component analysis (PCA) with frequency-domain spectral data was performed to examine the qualitative difference of these 3 classes of coffee beans using the first 3 score vectors. The 3 groups of different class of coffee beans were almost apart from each other in the space of the first 3 principal components (PCs), although there was some overlap among the groups, which may be due to that the first 3 PCs only accounted for the all spectral variations of 68.75%. Thus, to reduce the dimension of the model features and retain more information of the THz spectra of samples, the first 20 components were selected as the spectral characteristics for the determination of producing area of coffee bean. The support vector machine (SVM), as a learning algorithm used for classification and regression tasks, was used to get the identification model. During the iteration for the optimum parameters selection, the particle swarm optimization (PSO) was designed, which could enlarge search space and improve search efficiency. The identification results of the PSO-SVM were compared with the least squares - support vector machine (LS-SVM) and back propagation neural network (BPNN). From the comparison, it was showed that the discrimination accuracy of all 3 classes of coffee beans using the PSO-SVM was up to 95% in prediction set and 100% in calibration set, respectively, which was the best model among the 3 methods. It can be concluded that the THz frequency spectra can be used as important features to identify the producing area of the coffee bean. The model with SVM method based on PSO can get better parameters of SVM to improve the identification ability than the traditional LS-SVM. THz spectra system combined with the proposed algorithm has been proved to be a very powerful and attractive tool for identification of producing area of coffee bean. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Terahertz spectroscopy
Controlled terms:Calibration - Fast Fourier transforms - Frequency domain analysis - Iterative methods - Models - Neural networks - Optimization - Particle swarm optimization (PSO) - Pelletizing - Principal component analysis - Signal receivers - Spectroscopy - Support vector machines - Terahertz waves - Time domain analysis - Vectors - Water absorption
Uncontrolled terms:Back-propagation neural networks - Coffee beans - Discrimination accuracy - Least squares support vector machines - Qualitative differences - Spectral characteristics - Tera Hertz - THz time domain spectroscopy
Classification code:711 Electromagnetic Waves - 723 Computer Software, Data Handling and Applications - 802.3 Chemical Operations - 921 Mathematics - 922.2 Mathematical Statistics - 931.1 Mechanics
Numerical data indexing:Frequency 1.00e+11Hz to 4.00e+12Hz, Frequency 7.60e+09Hz, Percentage 1.00e+02%, Percentage 6.88e+01%, Percentage 9.50e+01%, Power 2.00e-02W, Time 5.00e-14s
DOI:10.11975/j.issn.1002-6819.2017.09.040
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 11>
Accession number:20172803930324
Title:Global dynamic collapse analysis of single-layer cylindrical reticulated shell in greenhouse under disaster wind loads
Authors:Wang, Junlin (1); Guo, Hua (1); Ren, Xiaoqiang (1); Sun, Jianheng (1)
Author affiliation:(1) Institute of Urban and Rural Construction, Hebei Agricultural University, Baoding; 071001, China
Corresponding author:Sun, Jianheng(sunjianheng@yahoo.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:195-203
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Single-layer cylindrical reticulated shell structures with the advantages in providing powerful transfer loads capability, large span space, excellent economic index, good light transmission performance and beautiful architectural style, not only are widely used in civil engineering, but also get more and more use in greenhouse construction because they can meet the requirement of rapid development of facility agriculture. Considering the high frequency of disaster winds in many regions of China, and the characteristics of reticulated shell structure including low overall stiffness, numerous vibration modes and great sensitivity to wind loads, the dynamic collapse may occur for single-layer reticulated cylindrical shell structure with large span and light weight in the weather of severe disaster winds. To analyze the collapse mechanism and the influence factor of this type of structure under wind loads is very important for the engineering design and theoretical analysis. In this paper, the analysis model of global dynamic collapse for single-layer cylindrical reticulated shell structure of greenhouse under wind loads was established by considering geometric nonlinearity, material nonlinearity and contact nonlinearity. In the numerical analysis, the effective plastic strain was defined to simulate the failure of tension members. To illustrate the influence of dynamic buckling of compression members on the collapse of the structure, each member was equally divided into 6 beam elements. The finite element explicit analysis software ANSYS/LS-DYNA was employed, and the dynamic buckling of compression members was considered. The collapse process of reticulated shell was analyzed and then was showed with the maximum nodal displacement, the deformed configuration and the plastic member distribution of the structure at different time. Based on the numerical analysis results and performance of the structure, the collapse process of reticulated shell was divided into 3 stages, which were named mild damage stage, collapse formation stage and overall collapse stage respectively. During the first stage (from the beginning to 21.7 s), the reticulated shell was generally in a deformation recoverable state with only a few members entering the plastic state in the compression area of the center and both ends of the structure. Therefore no local collapse occurred and little damage was produced to the structure performance. In the second stage (from 21.7 to 22.6 s), a series of dynamic buckling of members in the wind pressure zone from the bottom to the top of shell occurred, and a band-like buckling region was formed. At the same time, a number of tensile members entered the plastic state and gradually formed a plastic area. This weakened the stiffness of the structure, caused the structural vibration equilibrium position to deviate from its initial position, and finally caused the local collapse in the compression area of the structure. In the third stage (after 22.6 s), the plastic deformation of members in the buckling area of the reticulated shell reached its failure strain at first, and then the fracture failure of the members occurred. Under continuous dynamic forces, the collapse area rapidly expanded with the time, and finally led the shell to lose structural integrity completely at 24.8 s. In addition, considering most of the reticulated shell structures were supported with substructure, this paper also investigated the influence of substructure on the dynamic collapse performance of the upper reticulated shell under wind loads. The same reticulated shell model used above but without substructure was analyzed. The results of calculation showed that the load factor of the collapse of reticulated shell with substructure was reduced by 25% compared with that of the reticulated shell without substructure. The substructure would weaken the stiffness of the whole structure, and therefore reduce the wind loads bearing capacity of reticulated shell structure. It was necessary to consider the influence of substructure in the dynamic collapse analysis of reticulated shell structure under wind loads. Otherwise, the wind loads of the collapse of reticulated shell would be over-estimated. Based on the analysis results, some conclusions are drawn, which provide the basis theoretical reference for engineering analysis and further studies of reticulated shell structure in modern greenhouse. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Loads (forces)
Controlled terms:Aerodynamic loads - Buckling - Disasters - Dynamic loads - Finite element method - Fracture - Greenhouses - Light transmission - Loading - Models - Numerical analysis - Plastic deformation - Safety engineering - Shells (structures) - Stages - Stiffness - Strain measurement - Structural dynamics - Wind effects - Wind stress
Uncontrolled terms:Contact non linearities - Dynamic collapse - Effective plastic strain - Reticulated shell structure - Single-layer cylindrical reticulated shells - Single-layer reticulated cylindrical shells - Transmission performance - Wind load
Classification code:402.2 Public Buildings - 408 Structural Design - 443.1 Atmospheric Properties - 651.1 Aerodynamics, General - 691.2 Materials Handling Methods - 741.1 Light/Optics - 821.6 Farm Buildings and Other Structures - 914 Safety Engineering - 921.6 Numerical Methods - 943.2 Mechanical Variables Measurements - 951 Materials Science
Numerical data indexing:Percentage 2.50e+01%, Time 2.17e+01s, Time 2.17e+01s to 2.26e+01s, Time 2.26e+01s, Time 2.48e+01s
DOI:10.11975/j.issn.1002-6819.2017.09.025
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 12>
Accession number:20172803930318
Title:Influence of rainfall and roughness on hydrodynamic characteristics of overland flow
Authors:Wang, Junjie (1, 2, 3, 4); Zhang, Kuandi (1, 2, 3, 4); Yang, Miao (1, 2, 3, 4); Fan, Dian (1, 2, 3, 4); Gong, Jiaguo (1, 2, 3, 4)
Author affiliation:(1) Yellow River Branch of Shanxi Provincial Land Engineering Construction Group, Xi'an; 710000, China; (2) College of Water Conservancy and Architectural Engineering, Northwest A&F University, Yangling; 712100, China; (3) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Chinese Academy of Sciences, Yangling; 712100, China; (4) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100038, China
Corresponding author:Zhang, Kuandi(zhangkuandi428@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:147-154
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Overland flow is the initial motivation of slope surface erosion and the key reason for soil degradation. In order to study the influence of rainfall intensity and roughness on slope surface water dynamic characteristic, the artificial simulated rainfall experiments were carried in the Soil and Water Conservation Engineering Laboratory in Northwest A&F University. Based on the basic theory of fluid mechanics and hydraulics, the influence of rainfall intensity and roughness on hydrodynamic characteristics of overland flow was meticulously investigated. The experiment included 6 roughness, 5 flow discharges and 5 rainfall intensity. The theory of friction velocity and viscous sublayer in sediment movement mechanics were also applied in this study. Results showed that under the stage of overland flow, the data points of flow resistance coefficient was far from the laminar flow line and turbulent flow line with the continuous increase of roughness when the roughness was smaller than or equaled to 1.77 mm, indicating that the bed surface roughness of slope surface had an effect of resistance increase to flow resistance. However, the resistance coefficient fluctuated to being relative stable when the roughness was greater than 1.77 mm. Under the rainfall condition, the resistance coefficient decreased with the increase of rainfall intensity when roughness was closer to 0. In addition, the resistance coefficient was concentrated when the roughness increased. Under the stage of different rainfall intensity and roughness, the overland flow was accompanied by production and disappearance of roll wave. The phenomenon could be expressed by the ratio of viscous sublayer thickness and mean water depth. By observation, the ratio at roughness of 3.68 mm when the roll wave was obvious was calculated. When the ratio was between 0.382 4 and 0.599 3 (the difference was 0.24), the overland flow was in transition zone, otherwise, in roll wave zones. On the conditions of same roughness and rainfall intensity, Darcy-Weisbach resistance coefficient would decrease with the increase of turbulent flow Reynolds number. Under the condition of the same roughness, the resistance coefficient decreased with the increase of rainfall intensity. The resistance coefficient was 1.25-2.6, 1.3-2.7, 1.8-3.0, 1.8-3.15, 1.8-3.15, showing a trend of increase than being stable with increase of resistance coefficient. The turbulent flow Reynolds number was 0.35-36.1, belonging to transitional flow zone (0.35-900) according to turbulent flow Reynolds number standard but belonging to transitional and laminar flow zone according to traditional Reynolds number standard. It indicated that the standard for overland flow deserved further study. Based on the critical water depth, the overland flow was in rapid zone mostly. As the roughness increased, the flow transferred from rapid zone to slack zone. In addition, this study provided an overland flow resistance calculation formula by comprehensively considering viscous resistance, circle resistance and rainfall resistance. By validation, the formula had a high accuracy with R<sup>2</sup>of 0.92 (P<0.05). The results are helpful to understand hydraulic flow erosion mechanism of slope surface, and provide data support for building soil erosion model. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Flow of fluids
Controlled terms:Erosion - Fluid dynamics - Fluid mechanics - Hydrodynamics - Laboratories - Laminar flow - Precipitation (chemical) - Precipitation (meteorology) - Rain - Reynolds number - Roughness measurement - Soil conservation - Soils - Surface roughness - Turbulent flow - Water conservation
Uncontrolled terms:Artificial simulated rainfall - Engineering laboratories - Flow-resistance coefficients - Hydrodynamic characteristics - Overland flow - Rainfall intensity - Roll waves - Soil and water conservation
Classification code:443.3 Precipitation - 444 Water Resources - 483.1 Soils and Soil Mechanics - 631.1 Fluid Flow, General - 802.3 Chemical Operations - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Size 1.77e-03m, Size 3.68e-03m
DOI:10.11975/j.issn.1002-6819.2017.09.019
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 13>
Accession number:20172803930335
Title:Active anti-icing method for agricultural product refrigerated equipment based on phase change energy release
Authors:Cong, Qian (1, 2); Chen, Tingkun (1); Li, Yang (1); Sun, Chengbin (1); Jin, Jingfu (1)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun; 130022, China; (2) State Key Laboratory of Automotive Simulation and Control, Jilin University, Changchun; 130022, China
Corresponding author:Jin, Jingfu(jinjingfu@jlu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:276-281
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The application of refrigeration in agricultural and sideline products preservation is getting more and more extensive. However, the surface of refrigeration equipment, such as evaporator, condenser and chiller, is prone to freeze, and ice and frost are easy to occur, which seriously affect the operation efficiency of refrigeration equipment and increase the cost. The formation of ice must be accompanied by the phase expansion. So, why not use the phase transition expansion as the deicing power, and make the refrigeration equipment surface own active control ability of ice? During the test, the polymethyl methacrylate (PMMA) with pit and the aluminum alloy were used as the matrix materials, which were bonded with the biaxially oriented polypropylene (BOPP) elastic film as the freezing interface. The pit of the PMMA was filled with gas or aqueous solution with different freezing point. The test adopted the cup method to make the ice under -25℃ temperature. With the same cup, the test directly adopted the measured peeling force as the icing adhesion strength. The experimental results showed that the influence of the freezing medium with different freezing point on the icing adhesion strength was different. Compared with icing adhesion strength on the smooth specimen surface 169.81 kPa, the icing adhesion strength of the sample filled with the pure water in the pit was 0 kPa, decreased by 100%. And the icing adhesion strength of the sample filled with 6% ethanol solution was declined by 82% compared with the smooth specimen. Compared with the aluminum alloy sample surface, the icing adhesion strength of the sample filled with the solution of low freezing point was reduced by 76.52%. The icing adhesion strength of the sample filled with 6% ethanol solution was the smallest among the samples with the pits filled with alcohol solution. After the test, it was found that the expansion bump with different height occurred on the surface of the BOPP film on the surface of the pits, and the maximum height (3.34 mm) was on the surface of the specimen filled with pure water, followed by the sample filled with 6%, 8% and 10% ethanol solution, whose swell bump heights were 1.25, 1.13 and 1.04 mm, respectively. The results showed that the icing adhesion strength would be reduced by the phase expansion energy owing to the time difference of phase change. What was more, the influence of sample material, size of pit and filled solution on the icing adhesion strength decrease was very small. During the test, BOPP elastic film was used as the icing interface, and the rigid freezing interface under normal conditions was transformed into a flexible freezing interface. Due to the different thermal conductivity, the moisture on the film was first frozen, and the water solution in the pit formed the boundary constraints. After the aqueous solution was frozen into ice, the swell was generated and the energy was released. The energy played a role on the BOPP elastic film, and it destroyed the contact stability of the interface and reduced the icing adhesion strength. Therefore, it is feasible to destroy the contact stability of the elastic freezing interface and reduce the surface icing strength by the phase transition expansion caused by the coupled effect of ice itself and time difference of the phase transition using different aqueous solutions. The experimental results could provide a reference for studying and developing of anti-icing during agricultural product refrigeration field. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Phase interfaces
Controlled terms:Adhesion - Agricultural products - Agriculture - Aluminum - Aluminum alloys - Bond strength (materials) - Equipment - Ethanol - Expansion - Freezing - Ice - Ice control - Interfaces (materials) - Phase transitions - Polymethyl methacrylates - Polypropylenes - Refrigeration - Solutions - Testing - Thermal conductivity
Uncontrolled terms:Alcohol solutions - Bi-axially oriented polypropylenes - Boundary constraints - Contact stability - Elastic films - Ethanol solutions - Operation efficiencies - Refrigeration equipment
Classification code:443.3 Precipitation - 541.1 Aluminum - 541.2 Aluminum Alloys - 641.1 Thermodynamics - 644.1 Refrigeration Methods - 801.4 Physical Chemistry - 804.1 Organic Compounds - 815.1.1 Organic Polymers - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 901 Engineering Profession - 951 Materials Science
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.00e+02%, Percentage 6.00e+00%, Percentage 7.65e+01%, Percentage 8.00e+00%, Percentage 8.20e+01%, Pressure 0.00e+00Pa, Pressure 1.70e+05Pa, Size 1.04e-03m, Size 1.13e-03m, Size 3.34e-03m
DOI:10.11975/j.issn.1002-6819.2017.09.036
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 14>
Accession number:20172803930328
Title:Influence of droplet size and deposition on slightly acidic electrolyzed water spraying disinfection effect on livestock environment
Authors:Zang, Yitian (1); Li, Baoming (2); Zheng, Weichao (2); Sheng, Xiaowei (1); Wu, Hongxiang (1); Shu, Dengqun (1)
Author affiliation:(1) College of Animal Science and Technology, Jiangxi Agricultural University, Nanchang; 330045, China; (2) Key Laboratory of Structure and Environment in Agricultural Engineering, Ministry of Agriculture, China Agricultural University, Beijing; 100083, China
Corresponding author:Shu, Dengqun(13607047771@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:224-229
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As the increasing demand for efficient and sustainable production and the global demand for reduced antimicrobial drug consumption in livestock production, the importance of disinfection has increased significantly. However, potentially toxic, corrosive problems have arisen because of the use of chemicals as disinfecting agents. Slightly acidic electrolyzed water (SAEW) which has recently been developed in livestock production is a new environmental friendly disinfectant. In order to make the precision spraying of this disinfectant and increase the disinfectant usage efficiency for reducing residual and disease risk, in this study, the influence of droplets size and deposition on disinfection effect of slightly acidic electrolyzed water was evaluated. Deposition delivered by different atomizers on three aperture types (0.1, 0.3 and 0.5 mm) of sprayer under three levels pressure (30, 50 and 80 MPa), were first measured at 1 minute using a weighing method. The depositions were then divided into different levels with its correspondence pressure and aperture, and the trend influence of disinfection effectiveness of slightly acidic electrolyzed water (SAEW, pH value 6.15-6.35, ACC 135 mg/L), for inactivating Salmonella enteritidis on the surface of clothes, was evaluated at different levels of deposition. In addition, the effect of droplet size on SAEW sprayed disinfection effect was measured with two sprayers, nebulizer (size 80-90 μm) and ultrasonic nebulizer (size ≤30 μm) at different point-central district (A<inf>0</inf>) and another two different-distance points in the left and right hand (A<inf>1</inf>, A<inf>2</inf>). The results showed that deposition constitutes a dense neighborhood at central district (A<inf>0</inf>), more segmental in another two different-distance points (A<inf>1</inf>, A<inf>2</inf>) under the different pressure and aperture types. The deposition amount at the A<inf>0</inf>was more than A<inf>1</inf>and A<inf>2</inf>. In addition, the deposition amount at A<inf>1</inf>and A<inf>2</inf>first increased and then decreased as the pressure and aperture increased. The coefficient of variation from the different points was observed at the same change trend with A<inf>1</inf>and A<inf>2</inf>. The results showed that the deposition significantly affects the log reduction (P<0.05), and the logarithm of reduction of Salmonella was rapidly increased from (1.22±0.02) to (2.09±0.01)lg(CFU/mL), and then change little with the increased deposition. The maximum logarithm of reduction of Salmonella of 2.09±0.01 was finally obtained by the clothes sprayed with SAEW at 1.49×10<sup>-2</sup>deposition, and the deposition of 1.49×10<sup>-2</sup>g/cm<sup>2</sup>may be the best point of deposition for SAEW sprayed disinfection on the surface of clothes. There was a significant difference in the size of droplet on SAEW spraying disinfection effect (P<0.05). It was concluded that the bactericidal effects of the droplet from the nebulizer (size 80-90 μm) at the central target region, was significant higher than the ultrasonic nebulizer (Size≤30 μm) (P<0.05), but the effects of the nebulizers was significant difference at the different locations (P<0.05), and no significant difference (P>0.05) in the bactericidal effects of the ultrasonic nebulizer was observed among different locations. It means the smaller droplet size (size ≤30 μm) had a better uniformity than the larger size droplet (size 80-90 μm) © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Disinfection
Controlled terms:Agents - Agriculture - Atomization - Bactericides - Deposition - Disinfectants - Drops - Salmonella - Spraying - Sustainable development
Uncontrolled terms:Bactericidal effects - Coefficient of variation - Droplet sizes - Environmental-friendly - Salmonella enteritidis - Slightly acidic electrolyzed waters - Sustainable production - Ultrasonic nebulizers
Classification code:461.6 Medicine and Pharmacology - 461.9 Biology - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Mass_Density 1.35e-01kg/m3, Pressure 5.00e+07Pa, Pressure 8.00e+07Pa, Size 3.00e-04m, Size 5.00e-04m, Size 8.00e-05m to 9.00e-05m, Time 6.00e+01s
DOI:10.11975/j.issn.1002-6819.2017.09.029
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 15>
Accession number:20172803930311
Title:Applicability on continuous medium hypothesis in design of emitter using PIV and LBM method
Authors:Ma, Shengli (1); Wei, Zhengying (1); Zhang, Yubin (1); Chen, Xueli (1); Ma, Chao (1)
Author affiliation:(1) State Key Lab for Manufacturing System Engineering, School of Mechanical Engineering, Xi'an Jiaotong University, Xi'an; 710049, China
Corresponding author:Wei, Zhengying(zywei@mail.xjtu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:92-98
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The characteristics of microfluidic devices are different from those of ordinary fluid devices. One of the most important features of microfluidic devices is the decrease of their characteristic scale. This feature leads to a lot of differences in microfluidic device. Two major differences are included. There are the flow law of the fluid and the physical properties of fluid. The flow law of the fluid in a microfluidic device is different from that in an ordinary fluid device. The physical properties of the fluid in a microfluidic device also differ from that in an ordinary fluid device. The emitter channel is small in size from the point view of its width. As a result, the emitter belongs to the microfluidic device. Therefore, the applicability of Navier-Stokes (NS) equations has been controversial in the analysis of the flow characteristics in the emitter channel. In order to verify the suitability of the continuity medium hypothesis in design of the emitter, the lattice Boltzmann method (LBM) was used to study the flow characteristics of the emitter in this paper. The flow rate field on a specific plane obtained by different numerical methods was analyzed. The numerical methods were LBM and the computational fluid dynamics (CFD) method which was based on the finite volume method. The flow rate field obtained by using the two numerical methods was also compared with the experimental results. The flow rate with larger flow rate gradient of the straight line on the specific plane was also compared and analyzed. Firstly, the mesh independent analysis was made in order to guarantee the numerical accuracy of numerical results. Secondly, the numerical results were compared with those obtained by the finite volume method (FVM) based on the assumption of continuous medium. The numerical results were also made a comparison with the particle image velocimetry (PIV) experimental results. The average relative deviations of the results of the LBM calculation from the experimental values of PIV were analyzed. In addition, the average relative errors of the results of the FVM calculation from the experimental values of the PIV were also analyzed. By comparing flow rate contours, the results showed that the overall flow rate field calculated by the LBM in the specified cross section was in good agreement with the flow rate field measurement by the experiment, and the results also showed that the flow rate field calculated by the CFD method in the specified cross section was in good agreement with the flow rate field measurement by the experiment. The flow rate contour which was calculated by the LBM or CFD showed a large flow rate gradient at the corner of the contraction section. Comparing the flow rate on the specified measurement line, CFD reached its maximum flow rate on the measurement line where the distance was 0.482 mm, and the flow rate obtained by using the computational fluid dynamics method which was based on the finite volume method was 1.176 m/s. The flow rate of PIV experimental results was 1.09 m/s. The flow rate obtained by using the LBM reached its maximum value, and the result of the flow rate obtained by using the LBM was 1.06 m/s. Therefore, the relative error of flow rate obtained by using the CFD from the experimental result at 0.482 mm was 7.8%, which was larger than that of LBM which had the relative error of 2.7%. In view of the arithmetic mean of the relative deviation, the results showed that the arithmetic mean of the relative deviation of the CFD deviation from the PIV experiment was 0.139%, while the arithmetic mean of the relative deviation of LBM deviation was 0.115%. The results were very close. Therefore, the computational fluid dynamics method based on the assumption of continuous medium is applicable for analysis of the flow field in the emitter which has the characteristic size of 1 mm. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Computational fluid dynamics
Controlled terms:Boltzmann equation - Dynamics - Errors - Finite volume method - Flow rate - Flow visualization - Fluid dynamics - Fluidic devices - Microfluidics - Navier Stokes equations - Numerical methods - Physical properties - Velocimeters - Velocity measurement
Uncontrolled terms:Average relative error - Computational fluid dynamics methods - Continuous medium - Emitter - Flow charac-teristics - Lattice boltzmann methods (LBM) - Micro-fluidic devices - Particle image velocimetries
Classification code:631 Fluid Flow - 631.1 Fluid Flow, General - 632.2 Hydraulic Equipment and Machinery - 632.5.1 Microfluidics - 921.2 Calculus - 921.6 Numerical Methods - 922 Statistical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 943.3 Special Purpose Instruments
Numerical data indexing:Percentage 1.15e-01%, Percentage 1.39e-01%, Percentage 2.70e+00%, Percentage 7.80e+00%, Size 1.00e-03m, Size 4.82e-04m, Velocity 1.06e+00m/s, Velocity 1.09e+00m/s, Velocity 1.18e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.09.012
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 16>
Accession number:20172803930322
Title:Development and experiment of intelligent monitoring system for geese house environment
Authors:Guo, Binbin (1); Sun, Aidong (2); Ding, Weimin (1); Shi, Zhendan (2); Zhao, Sanqin (1); Yang, Hongbing (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing; 210031, China; (2) Jiangsu Academy of Agricultural Sciences, Nanjing; 210014, China
Corresponding author:Ding, Weimin(wmding@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:180-186
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Out-of-season breeding technology for goose was proposed due to their obviously seasonality of production. Precisely time control is the most critical factor in this technology. Simultaneously, temperature and humidity control are also needed in case of heat stress. The application of the new technology brings challenges to the traditional breeding methods. Environment control in goose house was mostly artificial or semi mechanized. Manual operation was of poor real-time performance, and could not achieve the organic connection between the various environmental factors. Light, temperature, relative humidity and other environmental parameters could not be recorded real-time. When diseases or some abnormal reproduction happen, managers could not trace causes from the aspect of environment. This study therefore was conducted to develop an intelligent geese house environment monitoring system for assisting geese out-of-season breeding practices. In the system, BP neural network was utilized to construct an intelligent control model with history temperature and relative humidity data. With this model, the system could make comparison between current temperature and relative humidity inside and outside, so as to determine the number of working fans and the on-off state of cooling pad. GPRS wireless transmission module was used to transmit in-house environmental parameters. With this system, mobile terminal GSM function was also utilized to remote control the geese house equipment such as fans, illuminating lights, pumps and cooling pads. On the basic framework technology of EXT, Hibernate and Spring, a J2EE enterprise web application was built. This made it possible of remote control and real time monitoring. In addition, users could also obtain the environment conditions from mobile client or remote control the corresponding equipment. Field tests were conducted in comparison with artificial control and other commercially developed animal house monitoring systems. The system had been running for more than five months. Results showed that this system was stable and reliable during long-term operation, and could meet the requirements of light, temperature and relative humidity of out-of-season breeding. Compared with artificial control and Shanghai Fanlong controller, the control precision was improved by 5.49% and 2.83%, respectively, labor cost was cut down by 50%. Geese elimination rate was decreased by 1.09% and 0.62%, respectively. With the method of cooling pads system in summer, the RMSE between in house temperature of BP neural network (A3), artificial experience (A2), setting static operating point(A4) and the set values were 0.202, 0.494 and 0.372℃, respectively, and relative humidity was 1.745%, 3.166% and 2.621%, respectively. Under the precise control of light, geese in all three houses exhibited normal onset and level of egg laying. They began to lay eggs from May 1st, and rose to the peak level in about one month. During hot summer, there was no heat stress of geese in A3, they showed steady laying rate, while laying rate of geese in A2 and A4 showed varying degrees of decline. At the peak of egg production, all three groups maintained their laying rate between 35% and 45%. From May 1st to October 1st, the mean daily egg laying rate of A2, A3 and A4 are 24.77%, 31.17% and 27.94%, respectively, which indicated that the intelligent control system of geese house environments allowed geese to exhibit normal out-of-season production performances. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Monitoring
Controlled terms:Compensation (personnel) - Controllers - Cooling - Cooling systems - Environmental management - Global system for mobile communications - Ground penetrating radar systems - Heating - Houses - Humidity control - Intelligent control - Neural networks - Remote control - Temperature - Thermal stress - Wages
Uncontrolled terms:BP neural networks - Environmental control - Geese out-of-season breeding - Intelligent monitoring systems - WEB application
Classification code:402.3 Residences - 454.1 Environmental Engineering, General - 641.1 Thermodynamics - 641.2 Heat Transfer - 716.2 Radar Systems and Equipment - 731.1 Control Systems - 732.1 Control Equipment - 912.4 Personnel - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Percentage 1.09e+00%, Percentage 1.75e+00%, Percentage 2.48e+01%, Percentage 2.62e+00%, Percentage 2.79e+01%, Percentage 2.83e+00%, Percentage 3.12e+01%, Percentage 3.17e+00%, Percentage 3.50e+01% to 4.50e+01%, Percentage 5.00e+01%, Percentage 5.49e+00%, Percentage 6.20e-01%
DOI:10.11975/j.issn.1002-6819.2017.09.023
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 17>
Accession number:20172803930326
Title:Performance on concentrating regeneration type solar soil deinsectization and sterilization device
Authors:Chang, Zehui (1, 2); Jia, Ningze (1); Hou, Jing (3); Zheng, Hongfei (4); Li, Wenlong (1); Liu, Yang (1)
Author affiliation:(1) College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot; 010051, China; (2) Key Laboratory of Wind and Solar Power Energy Utilization Technology Ministry of Education and Inner Mongolia Construction, Inner Mongolia University of Technology, Hohhot; 010051, China; (3) Chemical Engineering College, Inner Mongolia University of Technology, Hohhot; 010051, China; (4) School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing; 100081, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:211-217
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the last several decades, the problem of food shortage has been one of the main challenges in the world. It is necessary to enhance the use of protected agriculture in order to promote better microclimate conditions allowing high productivity, stable quality, earliest harvest dates and thus better economic output and good environment quality and food security. However, there are pests and pathogenic bacteria in the soil of agriculture production systems due to an ideal temperature, no wind and high humidity conditions in soil. Then soil disinfection treatments are used in agriculture before planting high-value cash crops, to reduce soil-borne crops pests including bacterial, fungal and nematode pathogens, weeds and insects. Methyl bromide fumigation is the widely used as a disinfection method due to its low cost and high effectiveness. But gaseous methyl bromide may destroy stratospheric ozone. Hence, forthcoming agro-ecological techniques should both reduce pollution hazards and be compatible with sustainable development guidelines. Many other chemical fumigants have become strongly restricted and more ecological treatments are now been sought. Alternative sustainable techniques such as soil electrical disinfection, steam soil disinfection and flame soil disinfection are utilized. However, many of these methods have the major drawbacks of their effect strongly depends on fossil energy. Moreover, the employment on a large scale of these methods could lead to a strong increase in environmental pollution. For this reason, in this paper, we presented a novel concentrating regeneration type solar soil extermination and sterilization device, which used high temperature air to kill soil-borne crop pests, reducing the employment of chemical fumigants and improving the quality of agriculture products. The device consisted of trough compound parabolic concentrating system, soil feed system, soil and air regeneration system and forced draft system, et al. The operational principle of concentrating light and regeneration type solar soil extermination and sterilization device was introduced. A 3D model of the concentrator supported with optical analysis software was used to analyze the tracking accuracy. The distribution of the concentrated light of the absorber could be visualized. Based on the simulation results, an experimental set-up, which can be used to verify the heat collection efficiency and the heating temperature, was designed and constructed. The results indicated that the overall ray's receiving rate of the trough compound parabolic concentrating collector of 99.66%-62.20% were obtained with radial incidence angles of 0°-7°. The outlet air temperature of the device increased with the decreasing the air flow rate. The maximum outlet air temperature of the device at the air flow rate of 1.075m/s was higher than that of the device at the air flow rate of 4.076 m/s by 70℃. Under good sunshine in winter, the outlet air maximum temperature of the device with the tracking accuracy of 5°and the concentrating rate of 3.6 can reach to 88℃, and the heat efficiency can reach about 65%, thus, it is able to provide enough heat to soil disinfection in the protected agriculture, which is an idea solar soil extermination and sterilization method for protected agriculture. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Soils
Controlled terms:Agriculture - Air - Atmospheric temperature - Bacteria - Concentration (process) - Crops - Disinfection - Ecology - Food supply - Forestry - Fumigation - Ozone layer - Pesticides - Pollution - Solar concentrators - Solar energy - Sterilization (cleaning) - Sustainable development
Uncontrolled terms:Agriculture productions - Concentrating - Concentrating collector - Environmental pollutions - Methyl bromide fumigation - Microclimate conditions - Operational principles - Protected agricultures
Classification code:443.1 Atmospheric Properties - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 657.1 Solar Energy and Phenomena - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 822.3 Food Products
Numerical data indexing:Percentage 6.50e+01%, Percentage 9.97e+01% to 6.22e+01%, Velocity 1.07e+00m/s, Velocity 4.08e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.09.027
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 18>
Accession number:20172803930329
Title:Preparation of denitrification and dephosphorization biological fillers and its effect on treatment of rural domestic sewage
Authors:Pan, Luting (1); Xie, Xinjue (1); Wang, Jiucheng (1); Dong, Hengjie (1)
Author affiliation:(1) Modern Agricultural Science and Engineering Institute, Tongji University, Shanghai; 200092, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:230-236
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the treatment of the rural domestic sewage, the total nitrogen(TN) and total phosphorus(TP) effluent concentration has been too high to comply with the class A of Pollutant Discharge Standard of Municipal Wastewater Treatment Plan(GB18918-2002). To solve this problem, a new type of denitrification and dephosphorization filer adopted in an anoxic filter (AF) - biological aerated filter (BAF) system was developed. The mass percentage of the raw materials of this fillers, namely steel slag, iron scrap, zeolite, activated carbon and cement, was 45%, 10%, 20%, 10% and 15%, respectively. The mixture of these materials at this mass ratio was then wrapped on the hollow float in the coating machine. The final product was produced after curing for a certain time. Due to the fact that the new fillers presented excellent synchronous nitrogen and phosphorus removal performances and were easy to prepare with low cost, they could be beneficial for promotion and application. The scanning electron microscope (SEM) results demonstrated that the fillers were of good hydrophilicity and rough surface. A large number of voids and large specific surface area was conductive to biofilm colonization. Optical microscope results showed that the biofilm was of good growth and high activity, which could remain long-term stable operation without backwash. And five main influencing factors (HRT, gas water ratio, reflux ratio and temperature) were investigated for the advanced treatment research. In the single factor experiment, when the value of the study factor was changed, TN and TP concentrations were measured for consecutive 4 days after the system got stable, and the average value was taken as the final result. The results showed that, within a certain range, the pollutants removal rate was proportional to HRT and temperature which means that the improvement of HRT and temperature exerted a positive effect on pollutant removal within a certain range. Besides, the removal rate tended to increase at first and then decrease with the rising of gas water ratio and reflux ratio. At the same time, the TN removal efficiency was significantly affected by temperature. The TN removal rate experienced an upward then a following downward trend with the increasing of temperature. In contrast, the TP removal rate increased slightly as temperature rose, drawing the conclusion that the changes of temperature had little effect on TP removal. Overall, the optimum conditions of this technology were as follows: HRT 5h, gas water ratio 10:1, reflux ratio 50% and 27℃, which was best for the nitrogen removal. With a stable system operation achieved, the effluent COD (chemical oxygen demand), NH<inf>3</inf>-N, TN and TP were 18.53, 0.66, 9.78 and 0.30 mg/L respectively and the removal efficiencies were 89.82%, 99.80%, 59.05% and 88.31%, respectively, which could meet the A class criteria specified in Pollutant Discharge Standard of Municipal Wastewater Treatment Plan(GB18918-2002). Through the comparative test conducted, the effect of the new filters was better than that of the ordinary commercial ceramic filters, which was of obvious advantages and development prospects. The results have provided reference for the practical engineering and theoretical study. © 2017, 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:Activated carbon - Activated carbon treatment - Biofilms - Biological sewage treatment - Carbon - Chemical oxygen demand - Denitrification - Efficiency - Effluent treatment - Effluents - Fillers - Filtration - Iron scrap - Nitrogen - Phosphorus - Pollution - Removal - Rural areas - Scanning electron microscopy - Sewage - Slags - Steel scrap - Wastewater treatment
Uncontrolled terms:Biological aerated filters (BAF) - Effluent concentrations - Large specific surface areas - Municipal wastewater treatment - Nitrogen and phosphorus removal - Removal mechanism - Single-factor experiments - The scanning electron microscopes (SEM)
Classification code:452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 462.5 Biomaterials (including synthetics) - 545.1 Iron - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804 Chemical Products Generally - 913.1 Production Engineering
Numerical data indexing:Age 1.10e-02yr, Mass_Density 3.00e-04kg/m3, Mass_Density 9.78e-03kg/m3, Percentage 1.00e+01%, Percentage 1.50e+01%, Percentage 2.00e+01%, Percentage 4.50e+01%, Percentage 5.00e+01%, Percentage 5.90e+01%, Percentage 8.83e+01%, Percentage 8.98e+01%, Percentage 9.98e+01%, Time 1.80e+04s
DOI:10.11975/j.issn.1002-6819.2017.09.030
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 19>
Accession number:20172803930320
Title:Consistency analysis of surface reflectance and NDVI between GF-4/PMS and GF-1/WFV
Authors:Sun, Yuanheng (1, 2, 3); Qin, Qiming (1, 2, 3); Ren, Huazhong (1, 2, 3); Zhang, Tianyuan (1, 2, 3)
Author affiliation:(1) Institute of Remote Sensing and Geographical Information System, School of Earth and Space Science, Peking University, Beijing; 100871, China; (2) Engineering Research Center for Geographical Information Basic Softwares and Applications under State Bureau of Surveying and Mapping, Beijing; 100871, China; (3) Beijing Key Lab of Spatial Information Integration and 3S Application, Peking University, Beijing; 100871, China
Corresponding author:Qin, Qiming(qmqin@pku.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:167-173
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As the first geostationary satellite of China's National High-resolution Observation Program (GaoFen Project), GaoFen-4 (GF-4) which launched in December 2015 enjoys the features of high temporal resolution and wide observation with a spatial resolution of 50 m. Meanwhile, GaoFen-4 together with GaoFen-1 (GF-1) polar-orbiting satellite forms a multi-spatial-temporal-resolution ground observation system, which provides more choices for agricultural remote sensing applications. Since the spectral responses of the Panchromatic Multispectral Sensor (PMS) boarded on GF-4 and Wide Field View (WFV) on GF-1 are slight different, there might be difference in reflectance measurements between them. To take fully advantage of their features, the imaging and vegetation detecting capability between two kinds of sensor are of great importance for us to explore in detail using image pairs from the areas of interest. In this study, we aimed at analysis of the continuity of surface reflectance and Normalized Difference Vegetation Index (NDVI) based on GF-4/PMS and GF-1/WFV sensors images. Two image pairs of Northern China Plain and its nearby mountain areas of China, acquired in May 2016, were employed for the comparison. Radiometric calibration, atmospheric correction and geometric correction were operated at first on the Level 1A images. Since there is discrepancy in spatial resolution between GF-4/PMS (50 m) and GF-1/WFV (15 m) images, two pixel-resampling methods were adopted not only to get a comparable surface reflectance image pair, but also to explore the scale effect on their continuity. Statistic indicators such as R<sup>2</sup>and RMSE were used to measure the continuity of their surface reflectance and NDVI, and linear regression model was adopted for surface reflectance rectification of GF-4/PMS images. Our results demonstrated that with spatial scale of the pixels increasing, the correlation of surface reflectance between GF-4 and GF-1 is also in increment. However, the uptrend of correlation speeds down or even reverses in blue band from 50 to 80 m. So 50 m is considered as an optimal spatial scale for the continuity study of GF-4 and GF-1 surface reflectance. The surface reflectance of GF-4 and GF-1 has a high positive correlation with R greater than 0.7 in all bands, but there is also bias. The bias includes systematic bias and random bias caused by sensors differences and outside factors, respectively. The major influence factor is the sensors' spectral response function, and it affects red band least. Other outside influence factors may include acquiring time, variation in atmospheric conditions and solar azimuths. Besides, BRDF effects were not under consideration in this paper either. The systematic bias can be reliably modified by a linear regression model, thus to predict GF-4/PMS reflectance from GF-1/WFV reflectance with an elimination of RMSE on surface reflectance between GF-4 and GF-1 remarkably. Meanwhile, the correlation coefficient R of NDVI increased slightly from 0.74 to 0.77 by the process of surface reflectance rectification, which proves that NDVI could weaken the effect of the surface reflectance bias. As a result, NDVI represents a much better continuity between GF-4 and GF-1 both before and after GF-4 surface reflectance rectification. Based on our experiment results, we suggest that GF-4 has a good continuity of China's GaoFen series satellites that enable its potential applications in the monitoring of agriculture and vegetation. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Reflection
Controlled terms:Agriculture - Application programs - Geostationary satellites - Image resolution - Linear regression - Orbits - Pixels - Regression analysis - Remote sensing - Satellites - Sensors - Vegetation
Uncontrolled terms:Consistency - GF-1 - GF-4 - NDVI - Surface reflectance
Classification code:655.2 Satellites - 723 Computer Software, Data Handling and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2 Mathematical Statistics
Numerical data indexing:Electric_Current 1.00e+00A, Size 1.50e+01m, Size 5.00e+01m, Size 5.00e+01m to 8.00e+01m
DOI:10.11975/j.issn.1002-6819.2017.09.021
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 20>
Accession number:20172803930327
Title:Engineering application of seawater-source heat pump for waste heat recovery in sea cucumber breeding system
Authors:Li, Xiuchen (1); Deng, Wei (1); Zhang, Dianguang (1); Mu, Gang (1); Zhang, Guochen (1); Chen, Shuai (1); Che, Quan (2)
Author affiliation:(1) R & D Center of Fisheries Equipment and Engineering of Liaoning Province, Dalian Ocean University, Dalian; 116023, China; (2) Dalian Xinyulong Seafood Industry Co. Ltd, Dalian; 116222, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:218-223
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to cut down energy consumption, heat loss and air pollution for water heating in indoor aquaculture system, a seawater-source heat pump system, which comprised 2 heat exchangers (namely I-stage exchangers) and a seawater-source heat pump and employed waste water as heating source, was developed and applied in an aquatic organism indoor nursing system. The onsite flow rate of waste water and fresh seawater in I-stage exchangers were regulated to 400 m<sup>3</sup>/h, respectively. The flow rate of waste water in the seawater-source heat pump was 20 m<sup>3</sup>/h, while the flow rate of fresh seawater increased from 10 to 20 m<sup>3</sup>/h during the onsite operation. The effectiveness for fresh seawater heating and the heat recovery of waste water by the seawater-source heat pump system were studied on site, and the amounts of energy consumption and carbon emission during the heating period were correspondingly calculated and compared with conditional coal-fired boiler heating approach. It showed that the heat-exchanging efficiency of I-stage heat exchangers was in direct proportion to the temperature difference of inflowing waste water and fresh seawater. When the inlet temperatures of waste water and fresh seawater were 10.3 and -1.9℃, respectively, the 5.8℃ increment of temperature in fresh seawater and 6.1℃ drop of temperature in waste water were observed. Additionally, with 14.9℃ inflowing waste water and 4.9℃ fresh seawater, the outlet temperature of fresh seawater increased to 9.5℃, while the waste water dropped to 10.0℃. The maximum heat recovery efficiency by I-stage exchangers from waste water was 59.5%. On the other hand, when the temperature and flow rate of inflowing waste water were not changed, the temperature increment of fresh seawater from the seawater-source heat pump was inversely proportional to its inflowing rate and temperature. With waste water of 14.9℃ as the heat source of the seawater-source heat pump, the temperature of fresh seawater increased from 7.3 to 18.6℃ at 10 m<sup>3</sup>/h and to 13.2℃ at 20 m<sup>3</sup>/h, which brought out temperature increment of 5.9-11.3℃. In the same case, the temperature of fresh seawater out of the seawater-source heat pump increased from 10.3 to 20.1℃ at 10 m<sup>3</sup>/h and to 16.6℃ at 20 m<sup>3</sup>/h, with temperature increment of 6.3-9.8℃. Accordingly, when the temperature of inflowing fresh seawater was 7.3 and 10.3℃, appropriate water temperature (15℃) could be obtained for aquatic organism indoor nursing by keeping the flow rate of fresh seawater at 15 and 20 m<sup>3</sup>/h, respectively. It was also found that the temperature drop of waste water in the seawater-source heat pump was about 6℃ during the operation, which gained the heat recovery efficiency of 40.7% for waste water. The coefficient of performance (COP) of the seawater-source heat pump was 5.03-5.52. In comparison with traditional coal-fired boiler heating approach, the integrated seawater-source heat pump system demonstrated significant drop in energy consumption (over 37.6%) and carbon dioxide emission (about 2 200 t/a). The payback period for the seawater-source heat pump system would be about 0.77 a. Therefore the seawater-source heat pump system has an obvious potential in energy conservation and carbon emission reduction in indoor aquaculture system. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Seawater effects
Controlled terms:Aquaculture - Aquatic organisms - Boilers - Carbon dioxide - Coal fired boilers - Drops - Emission control - Energy utilization - Flow rate - Gas emissions - Global warming - Heat exchangers - Heat pump systems - Heating - Investments - Metal recovery - Nursing - Pumps - Seawater - Temperature - Waste heat - Waste heat utilization - Wastewater - Water pollution
Uncontrolled terms:Carbon dioxide emissions - Carbon emission reductions - Coefficient of Performance - Engineering applications - Heat recovery efficiency - Sea cucumber - Seawater source heat pump - Water heating
Classification code:443.1 Atmospheric Properties - 451.2 Air Pollution Control - 452.3 Industrial Wastes - 453 Water Pollution - 461.7 Health Care - 471 Marine Science and Oceanography - 471.4 Seawater, Tides and Waves - 524 Solid Fuels - 525.3 Energy Utilization - 525.4 Energy Losses (industrial and residential) - 614 Steam Power Plants - 616.1 Heat Exchange Equipment and Components - 618.2 Pumps - 631 Fluid Flow - 641.1 Thermodynamics - 804.2 Inorganic Compounds - 821.3 Agricultural Methods
Numerical data indexing:Percentage 3.76e+01%, Percentage 4.07e+01%, Percentage 5.95e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.028
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 21>
Accession number:20172803930321
Title:Design and performance testing of production performance determination system for boar
Authors:Xiong, Benhai (1); Jiang, Linshu (2); Yang, Liang (1); Pan, Xiaohua (1)
Author affiliation:(1) State Key Laboratory of Animal Nutrition, Institute of Animal Sciences, Chinese Academy of Agricultural Sciences, Beijing; 100193, China; (2) Beijing Key Laboratory of Dairy Cow Nutrition, Beijing University of Agriculture, Beijing; 102206, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:174-179
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to monitor feeding behavior of sows and further attain the sow's precise feeding, an intelligent production performance testing system was designed in this study, which played functions in sows' automatic identification, body weight perception, automatic feeding data acquisition and data analysis simultaneously. The system was composed of electric ear tag identification module, precise feed flow control module, feed trough and boar weighing module, data communication and remote control module. The mechanical device system was constituted of feeding bin, brackets, railing and blocking apron. The mechanical device system was constituted of feeder's vertical wall, weighting platform, flapper, feed loading device, feed bin, control box, switch of discharge and ear tag recognizer. Electronic control systems included microprocessor (LPC1766, ARM Cortex-M3, Working temperature -40-105℃, Operating voltage 2.0-3.6 V, flash 256 K, low power consumption et al.), RS232 reader port, data storage chip (the default storage capacity is 256 KB), circuit of watchdog, weighing circuit, exterior-drivers circuit, JTAG connector circuit and stabilivolt source circuit. Among above, the sensor used for pigs weighing was Delux ADS1232 which had 2 rate options, 10 times per second and 80 times per second, with high precision and large range of features. The performance testing experiment revealed that: 1) the system's precision meets the monitoring requirement of sow production performance. The discharge rate of feeder depended on the level of feed in stock bin, and the average amount of unloading feed was 93±2 g at one time; the range of pig weighing was 0-200 kg with the precision error below 10 g, and the dynamic weighing error was below 0.5% of pig's weight. 2) The feeding behavior monitor for 40 gilts (25-60 kg) showed that the frequency of free feed intake was 10-12 times per day, the average feed time was 78 min, the feed conversion ratio was 2.33:1, and their weight gain was converged to the Gompertz curves (e.g. W<inf>t</inf>=172.1exp(-4.0187exp(-0.0122*t)), W<inf>t</inf>means body weight, kg; t means day old, day), the predicted decreasing daily weight gain of growing pigs by Gompertz curve occurred at day 111-117, with corresponding inflection point weight in the range of 63-64 kg. The observed and predicted results above could precisely determine the growth performance, indicating that the software systems and hardware devices could satisfy the requirement of growth performance determination in sows. 3) The wiper motor rather than early stepping motor was used in feed discharging control system, which reduced the cost of production. In addition, the combined wiper motor with cylindrical scraper structure decreased the discharge rate of feeder and improved the precision of unloading control system. 4) The core chip in control system was imported, multi-redundant, and protection systems were applied in circuit design. Multiply functional verification was adopted in software writing. The redundancy design in software and hardware eliminated the interference of power, electrical machine and electromagnetic wave, and improved the systems' reliability and stability. 5) The collected data could be saved or transferred, which facilitates the accumulation of pig production, data mining and sow breeding. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:17
Main heading:Identification (control systems)
Controlled terms:Anthropometry - Automation - Bins - Control systems - Data acquisition - Digital storage - Electric discharges - Electromagnetic waves - Feeding - Hardware - Integrated circuit manufacture - Mammals - Models - Printed circuit design - Redundancy - Software reliability - Software testing - Unloading - Verification - Weighing
Uncontrolled terms:Automatic identification - Boar - Data collection - Electronic control systems - Functional verification - Performance measurements - Production performance - Reliability and stability
Classification code:461.3 Biomechanics, Bionics and Biomimetics - 605 Small Tools and Hardware - 691.2 Materials Handling Methods - 694.4 Storage - 701.1 Electricity: Basic Concepts and Phenomena - 711 Electromagnetic Waves - 714.2 Semiconductor Devices and Integrated Circuits - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 722.1 Data Storage, Equipment and Techniques - 723.2 Data Processing and Image Processing - 723.5 Computer Applications - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 943.3 Special Purpose Instruments
Numerical data indexing:Mass 0.00e+00kg to 2.00e+02kg, Mass 1.00e-02kg, Mass 2.50e+01kg to 6.00e+01kg, Mass 6.30e+01kg to 6.40e+01kg, Percentage 5.00e-01%, Temperature 2.56e+02K, Time 4.68e+03s, Voltage 2.00e+00V to 3.60e+00V
DOI:10.11975/j.issn.1002-6819.2017.09.022
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 22>
Accession number:20172803930340
Title:Effect of vacuum degree of milking machine on milk somatic cell counts (SCC) and teat end wall thickness
Authors:Li, Xiaoming (1); Gao, Zhenjiang (1); Jin, Hongwei (2); Xiao, Hongwei (1); Wang, Jun (1); Zhang, Weiwei (3)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China; (2) China Agricultural Machinery Testing Centre, Beijing; 100122, China; (3) Dairy Association of China, Beijing; 100192, China
Corresponding author:Gao, Zhenjiang(zjgao@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:308-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The same type of milking machine has the different system vacuum degree, and its set value is mainly from experience and lacks a specific scientific basis. However, during milk processing, farms keep the factory setting value of system vacuum degree for all dairy cows, which causes obvious health problems of dairy cows. Therefore, it is imperative to provide the scientific setting basis of system vacuum degree by quantifying the effect of milking machine system vacuum degree on milking characteristics and cows' health. The dry test and wet test were carried out at China Agricultural Machinery Testing Centre. Simulation milking device was applied to simulate peak milking process with the milk flow of 4.0 kg/min for the high yield dairy cow and 2.5 kg/min for the low yield dairy cow. The pulsation rate and pulsation ratio were set to 60 cycles/min and 60%, respectively, which remained unchanged throughout the experiment. System vacuum degree was set at 44, 46 and 48 kPa, respectively, by means of the vacuum regulator. VaDia vacuum tester was used for data acquisition when milking machine ran under no-load or simulated the milking process at each system vacuum degree. The milking time test was carried out at a dairy cattle field in the north of Jinan, Shandong Province. The setting program of pulsation rate and pulsation ratio was the same in dry test and wet test. Twelve high yielding Chinese Holstein cows were randomly selected. In continuous 3 months (from July to September), milking machine system vacuum degree was set at 44, 46 and 48 kPa respectively. Milking was performed at 5:00 and 17:00 every day, and milk yield, somatic cell count (SCC), milking time (only in morning milking) and teat end wall thickness before and after milking (only in morning milking) were measured. All parameters measured were compared with ANOVA (analysis of variance) using SPSS. The comparisons of multiple means were made using the Duncan's multiple range test, in order to classify the effect of the different treatments. The logarithm of SCC was used to normalize the distribution of SCC. The results showed that during peak milk flow period and over milking period, system vacuum degree was increased from 44 to 48 kPa, and the increasing rate of liner vacuum degree was 4.9% (P<0.001) and 10.8% (P<0.001), respectively. Meanwhile, the increasing rate of milking cup mouth vacuum degree was 373.8% (P<0.001) and 53.7% (P<0.001), respectively. There were no significant differences for milk yield, average milk flow rate and milking time except the logarithm of SCC (P<0.05) between 44 and 48 kPa system vacuum degree. Percentage change of the teat end wall thickness was lower at the lower system vacuum level (44 kPa) after milking, and increased (P<0.05) as the system vacuum level was raised to 48 kPa. The findings of this study indicated that with a lower vacuum level of 44 kPa, the cows were milked better than those with 46 or 48 kPa. The findings in current work provide a technical support for the optimization settings of working state parameters of milking machine in mechanization milking parlors in China. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Milking machines
Controlled terms:Agricultural machinery - Agricultural products - Agriculture - Cells - Dairies - Processing - Software testing - Testing
Uncontrolled terms:ANOVA (analysis of variance) - Different treatments - End-wall - Milk yield - Somatic cell count - Technical support - Vacuum degree - Vacuum regulators
Classification code:461.2 Biological Materials and Tissue Engineering - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 822.1 Food Products Plants and Equipment - 913.4 Manufacturing
Numerical data indexing:Age 2.50e-01yr, Mass_Flow_Rate 4.17e-02kg/s, Mass_Flow_Rate 6.67e-02kg/s, Percentage 6.00e+01%, Pressure 4.40e+04Pa, Pressure 4.40e+04Pa to 4.80e+04Pa, Pressure 4.60e+04Pa, Pressure 4.80e+04Pa
DOI:10.11975/j.issn.1002-6819.2017.09.041
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 23>
Accession number:20172803930305
Title:Extraction of visual navigation directrix for harvesting operation in short-stalked and close-planting jujube orchard
Authors:Peng, Shunzheng (1); Kan, Za (2); Li, Jingbin (2)
Author affiliation:(1) College of Information Science and Technology, Shihezi University, Shihezi; 832000, China; (2) College of Mechanical and Electric Engineering, Shihezi University, Shihezi; 832000, China
Corresponding author:Li, Jingbin(ljb8095@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:45-52
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:An algorithm based on image processing technology was proposed for generating navigation directrix in complex circumstance of short-stalked and close-planting jujube orchard. The hatching method was used to analyze the distribution of target pixels and then proper processing image was obtained. Tree trunk and background were segmented based on B component of image which was binarized by threshold of each scan line. By analyzing the distribution of crossing points between tree truck and ground, the chief processing section, or the region of interest (ROI), was defined and chosen from two-fifths of image area below. Then in the light of trunk longitudinal gray scale distribution, tree trunks location was extracted with gray scale vertical projection method and morphology principle by setting a superficial window to dynamically scan ROI. In order to describe line trend in short-stalked and close-planting jujube orchard, trend lines were introduced, which included the right one and the left one in terms of ridge and furrow. To describe linear distribution trait of ridge and furrow, crossing points between tree and ground were obtained by comparing the shortest distance of candidate point to its corresponding trend line with a man-made threshold value. Afterwards, those selected points were classified separately into 2 clusters in terms of their distribution region which was located at right or left part of image longitudinal symmetry axis, with the point set available to fit the border line of ridge separately. The least square method was used for detecting the right and left border lines, and navigation directrix was generated by extracting the center points between 2 border lines. The method of extracting navigation path was searched by analyzing the condition of short-stalked and close-planting jujube orchard under harvesting operation, and the accuracy and reliability of the algorithm were analyzed and evaluated under a variety of environmental conditions. The study of the algorithm was still in the simulation stage and the specific navigation effect of the algorithm was related to the actual navigation operations, so algorithm performance could not fully represent the actual navigation applications. In order to measure the algorithm reliability and real-time parameters, 5 different scene conditions, which included 4 single factor working conditions and one multiple factor working condition, were tested. The experimental results showed that the algorithm could generate navigation directrix accurately and showed a good noise robustness. Under 4 single factor working conditions, the accuracy was more than 81.3%, and the average processing time consumed was less than 11.9 s to each frame image; by video detection, the accuracy was more than 83.4%, and the average processing time consumed was less than 1.7 s to each frame image. Under multiple factor working condition, the accuracy only reached 45% and the average processing time consumed was 9.4 s; by video detection, the accuracy only reached 42.3% and the average processing time consumed was 1.0 s. Therefore, for subsequent tasks, work should be done to improve the real time performance and practicality of the algorithm for various surroundings, so as to enhance the sensitivity of the algorithm under the multi-mode condition. The novelty of this paper is to propose several new methods to solve practical problems. The research provides a reference for autonomous navigation of robot in short-stalked and close-planting jujube orchard. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Image processing
Controlled terms:Crops - Farms - Forestry - Geometry - Image analysis - Image recognition - Least squares approximations - Machinery - Mechanization - Navigation - Orchards - Robots - Video signal processing
Uncontrolled terms:Autonomous navigation - Environmental conditions - Image processing technology - Real time performance - Row threshold division - The region of interest (ROI) - Trend line - Two-line
Classification code:601 Mechanical Design - 716.4 Television Systems and Equipment - 731.5 Robotics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 921.6 Numerical Methods
Numerical data indexing:Percentage 4.23e+01%, Percentage 4.50e+01%, Percentage 8.13e+01%, Percentage 8.34e+01%, Time 1.00e+00s
DOI:10.11975/j.issn.1002-6819.2017.09.006
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 24>
Accession number:20172803930333
Title:Identification of rural landscape functional conflicts based on land use competitiveness in southern Fujian
Authors:Liang, Fachao (1); Liu, Shiyuan (2); Liu, Liming (3)
Author affiliation:(1) School of Political Science and Public Administration, Huaqiao University, Quanzhou; 362021, China; (2) Construction Bureau of Jimei District, Xiamen; 361022, China; (3) College of Resources and Environment, China Agricultural University, Beijing; 100193, China
Corresponding author:Liu, Liming(liulm@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:260-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Urbanization and industrialization have led to the loss of rural landscape diversity and nativeness. The functional conflict in rural landscape becomes serious. This paper defined the rural landscape functional types. With the landscape functional types, we constructed the evaluation system of rural landscape functional competence, established the recognition system of rural landscape function conflict based on recognition matrix, and discussed the practical application of this method. The results showed that the method was consistent with the essential connotation of the rural landscape function conflict, and identified and predicted the types of rural landscape function conflicts. The production function competitiveness of rural landscape was high in the central area, however, was low around the central area in Guankou Town, Xiamen City. The distribution of production function competitiveness of rural landscape was consistent with the economic development level and transportation network of the whole town. The spatial distribution of life function competitiveness of rural landscape was consistent with that of production function. The areas with strong ecological function competitiveness were concentrated in the northern area with high vegetation coverage. There was a large area of ecological land patch in the northern part of the town. The central part of the town was dominated by the small patches with high appropriation, which indicated the urgent need for ecological improvement. There were 9 classes of rural landscape functional conflicts in Guankou Town. The production function advantage area occupied 3.89% of the total area of the town, which was located in the periphery of the town. The life function advantage area did not exist. The ecological function advantage area occupied 22.46% of the total area of the town, which was located in the mountainous area. It indicated the expansion of ecological function land, the gradual decrease of living space and the remarkable improvement of rural ecological environment. Based on the analysis of the regional characteristics of 9 types of rural landscape conflicts, the corresponding optimization strategies were put forward. High-quality cultivated land should give priority to the development of ecological agriculture in production function advantage area, the areas with fierce conflict between production and life function, and the areas with fierce conflict of 3 landscape function types. The government should guide the agricultural production to the modern ecotourism direction through the ecological subsidy policy. Rural landscape multi-functional suitability and conversion driving force were the sources of the conflict of rural landscape functions in southern Fujian. The functional land competitiveness evaluation model was developed for identifying the region of rural landscape function conflict and providing effective reference for preventing and resolving the rural landscape function conflict in southern Fujian. The results of the model can provide theoretic supports and methodological directions for carrying on rural landscape planning and rural land remediation. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Rural areas
Controlled terms:Agriculture - Competition - Ecology - Economics - Function evaluation - Land use - Models - Remediation
Uncontrolled terms:Agricultural productions - Competitiveness - Competitiveness evaluations - Ecological agricultures - Functional conflicts - Regional characteristics - Rural ecological environments - Rural landscapes
Classification code:403 Urban and Regional Planning and Development - 454.2 Environmental Impact and Protection - 454.3 Ecology and Ecosystems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics - 921.6 Numerical Methods - 971 Social Sciences
Numerical data indexing:Percentage 2.25e+01%, Percentage 3.89e+00%
DOI:10.11975/j.issn.1002-6819.2017.09.034
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 25>
Accession number:20172803930317
Title:Effects of rainfall intensity and slope on surface and subsurface runoff in red soil slope farmland
Authors:Chen, Xiaoan (1, 2); Yang, Jie (1); Tang, Chongjun (1); Zheng, Taihui (1); Li, Longfei (1)
Author affiliation:(1) Jiangxi Institute of Soil and Water Conservation, Jiangxi Provincial Key Laboratory of Soil Erosion and Prevention, Nanchang; 330029, China; (2) College of Water Conservancy and Hydropower Engineering, Hehai University, Nanjing; 210098, China
Corresponding author:Yang, Jie(zljyj@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:141-146
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The surface and subsurface runoff in the red soil slope farmland result in soil moisture and nutrient loss. In addition, the surface and subsurface runoff are important components contributing runoff at the watershed scale. An extensive literature shows that rain intensity and slope are two main factors playing an important role in the surface and subsurface runoff. In this paper, the surface and subsurface runoff in the red soil slope land under different rainfall intensities and slopes were studied by stimulated rainfall experiments in the flume (3.0 m length×1.0 m width×0.5 m depth) with variable slopes. The experiments were conducted in the Jiangxi Soil and Water Conservation Ecological Science and Technology Park. Stratified soil samples from different profiles including 0-20 cm (the plow horizon) and 20-40 cm (the plow pan) were collected and then filled respectively into the flumes by controlling the bulk density. For the rain intensity of 90 mm/h, we set four slopes including 5°, 10°, 15° and 20° in the simulated rainfall experiment. Three rain intensity levels (30, 60 and 90 mm/h) were set for the plots with slope of 10°. The results indicated that: 1) the subsurface runoff lagged behind the surface runoff, and the initiation time of the surface and subsurface runoff decreased with the increase of rainfall intensity from 30 mm/h to 90 mm/h. The lag time of the subsurface runoff initiation increased with the increasing rain intensity, and then tended to be stable; 2) the initial and steady surface runoff increased with the increase of the rain intensity; and the initiation subsurface runoff intensity increased with the increase of rainfall intensity. An increase trend was observed in the runoff produced by per unit rainfall; 3) the initial intensity of the surface runoff increased with the increase of rainfall intensity from 30 to 90 mm/h. However, no significant differences were found for the peak values of the subsurface runoff under different rainfall intensities. The attenuation curves of the surface runoff under different rainfall intensities were similar; 4) the obvious differences were observed between the runoff process curves of the surface runoff and subsurface runoff. The surface runoff increased firstly and then tended to be stable, but the soil subsurface runoff increased firstly and then decreased; 5) the initiation time of the surface runoff decreased with the increase of slope from 5° to 20°, but the initiation time of the subsurface runoff decreased firstly and then increased with the increase of the slope. The lag time of the subsurface runoff to the surface runoff also decreased firstly and then increased with the increasing slopes; 6) the surface runoff intensity first increased and then decreased with the increasing slope from 5° to 20° with a critical slope of 10°. The peak values of the subsurface runoff in soils increased firstly and then decreased with the increasing slopes. Moreover, the time to reach the peak value of the subsurface runoff decreased gradually with the increase of the slopes. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Runoff
Controlled terms:Agricultural machinery - Erosion - Farms - Infiltration - Precipitation (meteorology) - Rain - Soil conservation - Soil moisture - Soil surveys - Soils - Water conservation
Uncontrolled terms:Rainfall intensity - Red soils - Slope - Subsurface run-off - Surface runoffs
Classification code:443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 483.1 Soils and Soil Mechanics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment
Numerical data indexing:Size 0.00e+00m to 2.00e-01m, Size 2.00e-01m to 4.00e-01m, Size 3.00e+00m
DOI:10.11975/j.issn.1002-6819.2017.09.018
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 26>
Accession number:20172803930314
Title:Development and application of agricultural drought index based on CWSI and drought event rarity
Authors:Zhao, Huan (1, 2); Xu, Zongxue (1, 2); Zhao, Jie (1, 2)
Author affiliation:(1) College of Water Sciences, Beijing Normal University, Beijing; 100875, China; (2) Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, Beijing; 100875, China
Corresponding author:Xu, Zongxue(zxxu@bnu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:116-125
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural drought caused by soil water deficit exerts great influence on ecosystems and growth of crops. Accurate monitoring and detection of spatio-temporal characteristics of agricultural drought are meaningful for food security. However, agricultural drought is often characterized by current water demand-supply conditions, without considering the rarity of drought event in the historical period. In order to overcome the limitations of using crop water deficit indicator or dryness anomaly indicator only, an integrated evapotranspiration deficit index (IEDI) combining water deficit and dryness probability was proposed in this paper. To calculate the IEDI, crop water stress index (CWSI) ranging from 0 to 1 was calculated firstly based on actual evapotranspiration and potential evapotranspiration by remote sensing to reflect the actual level of crop water stress. Secondly, the drought event rarity index (RI) was derived on the basis of CWSI to reflect how often the current water stress occurred during the study period. The RI quantified the probability of the occurrence of an unusually dry event compared to normal state during the study period, and it was obtained by standardizing the cumulative density via the median of CWSI values. The calculation was based on the assumption that the statistical structure of CWSI follows Beta distribution and the median of CWSI time series represents normal water deficit state. In order to get an equal-interval value ranging from 0 to 1 quantifying how dry this crop water stress is compared to usual state, the RI was further derived using an empirical fitting method based on the standardized index. Finally, the proposed IEDI was derived, which was the square root of the product of CWSI and RI. On the basis of IEDI, temporal variations of agricultural drought in Northeast China, which is potentially threatened by climate extreme events, were analyzed. The impacts of meteorological factors on agricultural drought and the impacts of agricultural drought occurring period on grain yield were further investigated using the frequency analysis and the linear regression approach. Results showed that: 1) The proposed index was better for capturing the abnormal water stress state than the indicator based on current moisture deficit only, and the variations of peak value for IEDI showed high similarities to the RI. 2) High annual value of IEDI indicated severe drought condition. Thus, droughts in 2009 and 2014 in Liaoning Province, in 2007 and 2009 in Jilin Province, and in 2003, 2007 and 2009 in Heilongjiang Province were recognized as the most severe drought events during the study period, which were consistent with historical drought records. 3) IEDI was highly correlated with drought disaster area and grain yield in Northeast China. The correlation coefficients between drought disaster area and IEDI were all above 0.75, with the highest value of 0.88 in Jilin Province. The correlation coefficients between grain yield and IEDI were all above 0.60, with the highest value of 0.78 in Liaoning Province. 4) The correlation coefficients between grain yield and IEDI were higher than those between grain yield and CWSI in 4 major grain production cities: Liaoyuan, Siping, Songyuan and Changchun, manifesting a higher feasibility of IEDI to represent agricultural drought condition during study period. 5) Western Jilin and western Liaoning were the most sensitive regions to meteorological drought and were easily exposed to severe or extreme agricultural drought. 6) The correlation coefficients between IEDI and grain yield first increased and then decreased with the increase of drought duration when start month was fixed. And they were highly related to the start month when drought duration was fixed. Conclusively, the proposed index in this study is able to indicate agricultural drought effectively, which provides an effective way for agricultural drought monitoring. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:40
Main heading:Drought
Controlled terms:Agriculture - Crops - Disasters - Evapotranspiration - Food supply - Grain (agricultural product) - Plants (botany) - Remote sensing - Soil moisture
Uncontrolled terms:Actual evapotranspiration - Crop water stress indices - Development and applications - Index - Potential evapotranspiration - Rarity - Spatiotemporal characteristics - Water stress
Classification code:444 Water Resources - 483.1 Soils and Soil Mechanics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 822.3 Food Products
DOI:10.11975/j.issn.1002-6819.2017.09.015
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 27>
Accession number:20172803930323
Title:Thermal performance test of solidified sand heat storage wall in Chinese solar greenhouse
Authors:Bao, Encai (1); Zhu, Chao (2); Cao, Yanfei (1); Sun, Yachen (1); He, Bin (3); Mi, Xin (1); Zhang, Yong (1); Zou, Zhirong (1)
Author affiliation:(1) College of Horticulture, Northwest A&F University, The Agriculture Ministry Key Laboratory of Protected Horticultural Engineering in Northwest, Yangling; 712100, China; (2) College of Mechanical and Electric Engineering, Northwest A&F University, Yangling; 712100, China; (3) College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling; 712100, China
Corresponding author:Zou, Zhirong(zouzhirong2005@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:187-194
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Solar greenhouse has been widely used in the north of China. Chinese solar greenhouse is made of north wall, east wall, west wall, front roof, back roof and heat preservation quilt. The main materials of north wall in traditional Chinese solar greenhouses are soil and brick. However, in the northwest of China, there are many non-cultivated lands with many sands instead of soil resources. In this research, we designed a new kind of north wall (W1) which was made of 2 layers of porous bricks and contained the solidified sands. The solidified sand was in the middle of W1 and the porous bricks were at the outside layers of the solidified sands. The wall thickness was 1000 mm, with 760 mm thick solidified sands and 240 mm thick porous bricks. In order to store more heat into the wall, a new active storage wall (W2) was also developed based on the W1. Compared with the W1, a sand-air heat transfer system was added with 2 axial flow fans and 3-layer air passages, and the air conduits were 80 m long, which was developed to store more heat. The thermal environmental properties of the 2 newly designed greenhouse walls were evaluated in Wuhai (39°39'N, 106°47'E), Inner Mongolia Autonomous Region, China, which were also compared with the local solar greenhouses with porous bricks and EPS (W3). During clear days (for instance, from 9:00 on January 7<sup>th</sup>, 2016 to the next 9:00), the average daily air temperature in W1, W2, and W3 was 17.2, 20.5 and 16.9℃, respectively with an average outside temperature of -11.3℃. The average night air temperature in W1, W2, and W3 was 13.7, 17.0 and 12.8℃, respectively, indicating that W2 had the best heat storage ability. During cloudy days (for instance, from 9:00 on January 16<sup>th</sup>, 2016 to the next 9:00), the average night air temperature in W1, W2, and W3 was 10.6, 13.8 and 10.0℃, respectively, indicating that W2 also had the best heat storage ability. In order to have a better understanding of the thermal properties of the 3 greenhouse walls, we selected the indoor temperature data of consecutive 27 days from January 1<sup>st</sup>to January 27<sup>th</sup>, 2016. During this period, the minimum average air temperature in W1, W2 and W3 was 10.48, 10.51 and 9.57℃, respectively. The daily average air temperature was 14.97, 17.30 and 14.89℃. Solar greenhouse wall was an important factor for maintaining greenhouse heat balance. Wall heat storage ability was important for the greenhouse performances. The distributions and changes of temperature inside the wall reflected the heat exchange process between the wall and indoor air and had great impacts on the indoor temperature in greenhouses. The internal constant temperature region of the wall W1 was between 500 and 740 mm, and the thickness of the thermal storage body was about 500 mm. For the solidified sand body, the effective thermal storage thickness was up to 380 mm. For the W2, the internal constant temperature region ranged from 740 to 1 000 mm, and the effective thermal storage body thickness exceeded 740 mm, among which, the effective thermal storage body thickness of the solidified soil exceeded 620 mm. For the W3, the effective thermal storage body thickness and temperature fluctuations were relatively smaller and the thermal storage capacity was also the smallest. Under sunny days, for the W2, the effective thermal storage body included the 500 mm thick wall body and the inside of the air tubes and their outside up to 200 mm, indicating that active heat storage fan system could significantly improve the wall heat storage capacities in greenhouses. Our results indicate that the new designed greenhouse wall W2 has some important application values. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Greenhouses
Controlled terms:Atmospheric temperature - Axial flow - Brick - Digital storage - Heat storage - Roofs - Sand - Soil testing - Soils - Solar heating - Space heating - Storage (materials) - Temperature
Uncontrolled terms:Average air temperature - Chinese solar greenhouse - Environmental property - Inner Mongolia autonomous regions - Temperature fluctuation - Thermal storage - Thickness - Walls
Classification code:414.2 Brick Materials - 443.1 Atmospheric Properties - 483.1 Soils and Soil Mechanics - 631.1 Fluid Flow, General - 641.1 Thermodynamics - 643.1 Space Heating - 657.1 Solar Energy and Phenomena - 694.4 Storage - 722.1 Data Storage, Equipment and Techniques - 821.6 Farm Buildings and Other Structures
Numerical data indexing:Age 7.40e-02yr, Size 1.00e+00m, Size 2.00e-01m, Size 2.40e-01m, Size 3.80e-01m, Size 5.00e-01m, Size 5.00e-01m to 7.40e-01m, Size 6.20e-01m, Size 7.40e-01m to 1.00e+00m, Size 7.40e-01m, Size 7.60e-01m, Size 8.00e+01m
DOI:10.11975/j.issn.1002-6819.2017.09.024
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 28>
Accession number:20172803930334
Title:Suitability evaluation of living environment in Kai-Kong River Basin based on 3S
Authors:Aynur, Mamat (1, 2); Ümüt, Halik (1); Nasima, Nasirdin (1)
Author affiliation:(1) Key Laboratory of Oasis Ecology, College of Resource and Environment Science, Xinjiang University, Urumqi; 830046, China; (2) Kashgar Research Center of Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Kashgar; 844000, China
Corresponding author:Ümüt, Halik(halik@xju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:268-275
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid economic and social development, more and more concerns are on the survival of their own settlement environment. Human settlement environment is not only the basic space of human existence and activities, but also the concentrated expression of human civilization. In this paper, the Human Settlements Environment Index (HEI) model was built to evaluate the environmental suitability for human settlements in Kai-Kong River Basin, using the selected relief degree index, vegetation index, humidity index, hydrology index, and land use evaluation index, with the grid scale of 1 km×1 km. Through applying spatial analysis technique of ArcGIS software including spatial overlay analysis and density analysis, the spatial situation of human settlement environment suitability and spatial pattern for human living environment in Kai-Kong River Basin were systematically summarized and established.The results showed that the index of nature suitability for human settlement in the Kai-Kong River Basin was between 4.4 and 83.9. According to the correlation between the human distribution and the human environment index the human settlement environment in Kai-Kong river divided into five region, they are high suitable region, suitable region, general suitable region, unsuitable region and least suitable region. In general, suitability for human living environment decreased from middle plain areas to Tianshan mountain areas in the northwest and Taklimakan desert areas in the southeast. In the study area, the high suitable region was mainly distributed in Korla city, which accounted for about 124 km<sup>2</sup>, 0.2% of the total area of the study region. Suitable region was mainly distributed in bordering area of Bohu, Hejing, Heshuo, Yanji and Yuli county, which accounted for about 2 456 km<sup>2</sup>, 3.3% of the total area of the study region. General suitable region was mainly distributed in around the suitable region, which accounted for about 2 526 km<sup>2</sup>, 3.4% of the total area, this area was mainly located in the intersecting zone, so that it has a great potential for development. The unsuitable region was mainly distributed in upper stream of Kai-Kong River Basin which covered by snow and accounted for about 23 104 km<sup>2</sup>, 31% of the total area. The least suitable region was mainly distributed southwest part of the study area, this area was mainly composed by desert that characterized with high temperature, high evaporation, low precipitation and low vegetation cover, not suitable for human living and development, and it constitutes the largest parts of the whole study area, which accounted for about 46 301 km<sup>2</sup>, 62.1% of the total area. High Suitable regions and suitable regions for human living were distributed mainly around Kai-Kong River connecting region in the form of ribbons and batches. The high suitable region, suitable region and general suitable region accounted for 6.9% the total area of study region, and 98.8% of the total population in this area. Unsuitable region and the least suitable region accounts for 93.1% of the total study area, and only 1.2% of the total population distribution in this region. Results also indicated that the geographical environment of the study area is rather fragile. Therefore, it is not suitable for increasing population and conducting irrational land development activities in the Kai-Kong Rivers Basin. Spatial distribution of population was influenced and controlled by severe environmental conditions, such as the constantly expanding of deserts, the high terrains, and the complicated climate as well as the lack of hydrological conditions. Irrational agricultural production activities and slow economic growth was also the huge obstacles of suitability for human living environment in the Kai-Kong River Basin. According to these problems and various planning, it can be suggested that some of the residential areas are needed to relocate, in order to improve situation of residential environment. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Rivers
Controlled terms:Agriculture - Arid regions - Economics - Geographic information systems - Houses - Housing - Land use - Landforms - Models - Population distribution - Remote sensing - Spatial variables measurement - Vegetation - Watersheds
Uncontrolled terms:Economic and social development - Environmental conditions - Geographical environment - Living environment - River basins - Spatial distribution of populations - Suitability evaluation - Suitability for human settlements
Classification code:402.3 Residences - 403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 405.3 Surveying - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 481.1 Geology - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 903.3 Information Retrieval and Use - 943.2 Mechanical Variables Measurements - 971 Social Sciences
Numerical data indexing:Percentage 2.00e-01%, Percentage 3.10e+01%, Percentage 3.30e+00%, Percentage 3.40e+00%, Percentage 6.21e+01%, Percentage 6.90e+00%, Percentage 9.31e+01%, Percentage 9.88e+01%, Area 1.24e+08m2, Area 2.31e+10m2, Area 2.46e+09m2, Area 2.53e+09m2, Area 4.63e+10m2, Percentage 1.20e+00%
DOI:10.11975/j.issn.1002-6819.2017.09.035
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 29>
Accession number:20172803930332
Title:High standard farmland construction time sequence division based on cultivated land quality uniformity in administrative village scale
Authors:Song, Wen (1, 2); Wu, Kening (1, 2); Zhang, Min (1, 2); Li, Ting (1, 2); Liu, Peijia (1, 2)
Author affiliation:(1) School of Land Science and Technology, China University of Geosciences, Beijing; 100083, China; (2) Key Laboratory of Land Consolidation and Rehabilitation, Ministry of Land and Resources, Beijing; 100035, China
Corresponding author:Wu, Kening(wukening@cugb.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:250-259
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an important component of the land consolidation, high standard farmland construction is the important means to protect the quantity, quality and ecological environment of cultivated land, and its target not only lies in the increase of cultivated land's quantity, but also the improvement of cultivated land's quality, agricultural production conditions and ecosystem environments. Through this paper we tried to explore the method of cultivated land evaluation and construction zoning to facilitate the process of decision and implementation for high standard farmland construction. The land comprehensive improvement project area in Quzhou County was taken as a case study. The whole process of the study was made up of 3 steps: 1) Establishing the evaluation model of cultivated land quality uniformity based on regional optimum cultivated land quality, and constructing the uniformity evaluation index system of cultivated land quality from the aspects of soil quality, engineering quality, space quality, ecological environment quality and aesthetic quality according to the new concept of cultivated land quality; 2) calculating the cultivated land quality uniformity through grading indicators, assigning score and weighting sum; 3) carrying out high standard farmland construction time sequence partition according to the principle of easy first and difficult afterwards through analyzing regional cultivated land quality difference and obstacle factor index restriction. The results showed that the value of farmland quality uniformity of the administrative villages in the project area was between 7.03 and 22.40, and there was obvious difference between various administrative villages. Through the natural breaks method, the quality uniformity of cultivated land in the project area was divided into 3 levels. In detail, the high-level area included 8 administrative villages, and the cultivated area accounted for 20.98% of the total area of cultivated land in the project area; the plots of cultivated land in each administrative village were of high quality, and at the same time similar with the optimal quality level in the area. The middle-level area included 21 administrative villages and the low-level included 17, the cultivated area of which accounted for 48.59% and 30.44% of the total cultivated land area respectively. The plots of cultivated land were of medium and poor quality respectively, and the difference was comparatively large compared to the optimal quality level in the area. The most restrictive factors in the project area were the indicators with medium and low transformation difficulty, including soil organic matter content, forest density, field regularity and scale of field, and there were also the indicators with high transformation difficulty in some areas, such as sectional configuration. The project area was divided into 4 time sequence partitions including the major construction area, the secondary construction area, the general construction area and the conditional construction area, and the construction difficulty of these 4 areas was from easy to difficult; the cultivated land area of each subarea was 710.11, 2 199.04, 975.47 and 1 101.07 hm<sup>2</sup>, accounting for 14.24%, 44.11%, 19.57% and 22.08% of the total project area respectively. The evaluation model and index system can satisfy the requirements for the evaluation of the farmland quality and the diagnosis of obstacle factors to facilitate the subsequent construction decision. The study can be a reference for the practice of high standard farmland construction, and provide new ideas and methods for related research. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:37
Main heading:Quality control
Controlled terms:Agriculture - Construction - Ecology - Farms - Grading - Land use - Rural areas - Zoning
Uncontrolled terms:Agricultural productions - Cultivated land qualities - Ecological environments - Evaluation index system - High standards - Obstacle factor - Quzhou County - Soil organic matter contents
Classification code:403 Urban and Regional Planning and Development - 405 Construction Equipment and Methods; Surveying - 454.3 Ecology and Ecosystems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.3 Quality Assurance and Control
Numerical data indexing:Percentage 1.42e+01%, Percentage 1.96e+01%, Percentage 2.10e+01%, Percentage 2.21e+01%, Percentage 3.04e+01%, Percentage 4.41e+01%, Percentage 4.86e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.033
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 30>
Accession number:20172803930313
Title:Modeling stomatal conductance using root-water-uptake in ground cover rice production system
Authors:Jin, Xinxin (1, 2); Shi, Jianchu (1); Li, Sen (1); Ma, Wenwen (1); Zuo, Qiang (1)
Author affiliation:(1) College of Resources and Environmental Sciences, China Agricultural University, Beijing; 100193, China; (2) Institute of Cereal and Oil Crops, Hebei Academy of Agricultural and Forestry Sciences, Shijiazhuang; 050035, China
Corresponding author:Zuo, Qiang(qiangzuo@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:107-115
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Ground cover rice production system (GCRPS) has attracted great attention. The rice root system of GCRPS is under water stress, it is necessary to establish root water uptake models to quantify its root-water-uptake. The aim of this study was to investigate the relationship between transpiration (i.e. root-water-uptake) and root length, and thereupon to establish a root-water-uptake model under GCRPS. Furthermore, the Penman-Monteith (PM) equation was replaced by the validated root water uptake model to estimate transpiration rate and improve the traditional stomatal conductance model proposed by Tardieu-Davies (TD) in this study. A field experiment with 3 irrigation levels (named as TPRPS, GCRPS<inf>sat</inf>and GCRPS<inf>80%</inf>) was conducted in 2013 at Shiyan, Hubei province. Each treatment was designed and replicated 3 times in 9 plots, with an area of 9×10 m<sup>2</sup>. For treatment TPRPS, a water layer of 2-5 cm in thickness was always maintained on the soil beds. For GCRPS<inf>sat</inf>, soil water content in the root zone was kept close to saturation by completely filling the furrows with water but without water layer on the soil beds. For GCRPS<inf>80%</inf>, the management was the same way as that for GCRPS<inf>sat</inf>before mid-tillering stage, and then transient irrigation was intermittently implemented through the furrows to keep soil water content in the root zone between 80%-100% of field water holding capacity. A seepage-proof material was laid around each plot to the depth of 80 cm to avoid lateral percolation between neighbor plots. Five soil beds in each plot were built for planting rice, with the space of 26×18 cm<sup>2</sup>. Small furrows (15 cm in width and depth) were dug around each soil bed. The water saving characteristics of GCRPS were analyzed as a function of the measured soil water conditions, water input and consumption, and plant parameters regarding root growth and physical parameter were also determined. The soil water content under GCRPS was measured with a capacitance probe. Roots in each soil layer were washed via a sieve and analyzed for root length. Stomatal conductance of flag leaves were measured using a portable photosynthesis system. Experimental results showed that the potential transpiration rate was linearly proportional to the total root length of rice (R<sup>2</sup>=0.96, P<0.05). The root-water-uptake model established on the linear relationship simulated the dynamics of transpiration under GCRPS successfully, with the relative errors between simulated and measured transpiration rates less than 15%. The PM equation was replaced by the validated root water uptake model to estimate transpiration rate and to improve the TD model. The daily dynamics of stomatal conductance under GCRPS was simulated with the improved TD model by combining the established root water uptake model. The improved TD model was applied to estimate the ABA concentration of root water flow in various soil layers and evaluate the contribution of ABA synthesized in each root layer to that in transpiration flow in xylem. Compared with the traditional TD model, the improved TD model simulated the daily dynamics of stomatal conductance more accurately, with relative error less than 7.0% and root mean square error of 0.02 mol/(m<sup>2</sup>·s). This study can provide valuable information for understanding the physiological water saving mechanism and water use efficiency evaluation of GCRPS. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Water treatment
Controlled terms:Dynamics - Errors - Irrigation - Mean square error - Models - Physiological models - Plants (botany) - Soil moisture - Soils - Solvents - Transpiration - Water conservation
Uncontrolled terms:Rice production systems - Root length density - Roots - Stomatal conductance - Water uptake
Classification code:444 Water Resources - 445.1 Water Treatment Techniques - 461.9 Biology - 483.1 Soils and Soil Mechanics - 803 Chemical Agents and Basic Industrial Chemicals - 821.3 Agricultural Methods - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 1.50e+01%, Percentage 7.00e+00%, Percentage 8.00e+01% to 1.00e+02%, Size 1.50e-01m, Size 2.00e-02m to 5.00e-02m
DOI:10.11975/j.issn.1002-6819.2017.09.014
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 31>
Accession number:20172803930337
Title:Nondestructive testing of muskmelons varieties based on dielectric spectrum technology
Authors:Wang, Zhuanwei (1); Zhao, Chunjiang (2); Shang, Liang (1); Kong, Fanrong (1); Weng, Xiaofeng (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; 712100, China; (2) National Engineering Research Center for Information Technology in Agriculture, Beijing; 100097, China
Corresponding author:Zhao, Chunjiang(zhaocj@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:290-295
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To classify muskmelons quickly and accurately based on dielectric spectroscopy, dielectric properties of 4 kinds of melons (a total of 246) were measured with network analyzer over the frequency range from 20 to 4 500 MHz. The samples were selected from 4 different greenhouses in Yangling, Shaanxi Province, which had similar shape and size, and had no injury and disease. All samples were divided into calibration set and validation set with a ratio of about 3:1 based on Kennard-Stone method. Methods of support vector machine (SVM) and extreme learning machine (ELM) were applied to establish discriminative models of muskmelons. We chose 2 different variable selecting methods as pre-processing methods before modeling. One method was principal component analysis (PCA) for data dimension reduction, and the other was successive projections algorithm (SPA) for characteristic variables selecting. The model validating effects after the processing of PCA and SPA were used to compare with that with no pre-processing; besides, directly modeling with full frequencies (FF) spectra data was also adopted. The results were shown as below: 1) All discriminative models under FF, PCA and SPA methods could be used for classifying muskmelons. The total correct rate of each validation set reached over 96%, and the ELM modeling method was better than SVM method as a whole. 2) The models based on the FF method retained all original information of the frequency spectra data, so it had the highest validation correct rate, up to 100%. But its stability and reliability were not good enough because of the existing interference information. Under the PCA method, the accumulating contribution rate of the former 10 principal components extracted from all variables approached to 99.99%, which well reflected original information while simplifying the model in some degree and improved performance of models, however, the results were not very stable and the total correct rate of 2 models was much lower than others, up to 96.72% and 98.36% respectively. Seventeen characteristic variables were selected by the SPA from all 202 variables for modeling, which not only simplified the model and improved its performance, but also had the higher accuracy. Therefore, the SPA method was more suitable for the variables selecting based on dielectric spectrum. 3) In all models, SPA-ELM had the minimum misjudgments and the highest total correct rate, which was more suitable for classifying muskmelons according to dielectric frequency spectra. Therefore, it's feasible to classify muskmelons based on dielectric spectrum by the modeling methods of SVM and ELM. It also shows that the dielectric spectrum technology can be used to do more research on muskmelon classification and grading, and provides the new theory and methods for future research about nondestructive detection of muskmelons. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Principal component analysis
Controlled terms:Classification (of information) - Dielectric properties - Education - Grading - Knowledge acquisition - Learning systems - Models - Nondestructive examination - Processing - Spectroscopy - Support vector machines
Uncontrolled terms:Data dimension reduction - Dielectric frequencies - Discriminative models - Extreme learning machine - Muskmelon - Nondestructive detection - Stability and reliabilities - Successive projections algorithms (SPA)
Classification code:716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 723.4 Artificial Intelligence - 913.4 Manufacturing - 922.2 Mathematical Statistics - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Frequency 2.00e+07Hz to 4.50e+09Hz, Percentage 1.00e+02%, Percentage 9.60e+01%, Percentage 9.67e+01%, Percentage 9.84e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.038
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 32>
Accession number:20172803930300
Title:Simulation and validation for regional border irrigation considering spatial variability of irrigation parameters
Authors:Dong, Qin'ge (1, 2); Xu, Di (3); Zhang, Shaohui (3); Bai, Meijian (3); Li, Yinong (3)
Author affiliation:(1) Institute of Water and Soil Conservation, Northwest A&F University, Yangling; 712100, China; (2) Institute of Water and Soil Conservation, CAS & MWR, Yangling; 712100, China; (3) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100038, China
Corresponding author:Xu, Di(xudi@iwhr.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The performance evaluation of regional scale border irrigation plays an important role in the improvement of surface irrigation management level, but the existing models present the shortcomings such as less accurately capturing the spatial variability of regional scale irrigation parameters. So the exiting models cannot be effectively applied to analyze the performance of regional scale border irrigation system. To solve this problem, the border surface-subsurface flow model was applied to describe the surface and subsurface water flow. The conservative complete hydrodynamic equation and the Richards equation were applied to describe the surface water flow and subsurface water flow in border irrigation, respectively. The finite-volume approach was applied to spatially discretize these governing equations to obtain good mass conservation ability. The Picard iteration approach was introduced to obtain the linearization of this nonlinear algebraic system. The mass conservation component of surface flow model and subsurface flow model were iteratively coupled at the same time step to obtain the convergence value of surface flow depth, and then the momentum conservation component of surface flow model was externally coupled based on the convergence value of both the surface flow depth and infiltration rate to update the surface flow velocity. Solutions were numerically computed using an improved hybrid numerical method for surface flow model and a proposed numerical solution method with high-order accuracy for subsurface flow model. Monte-Carlo sampling method was used to accurately capture the spatial variability of regional scale irrigation parameters and generate a large number of border irrigation parameters samples, which were input to border surface-subsurface model, respectively. Consequently, the border surface-subsurface water flow processes of regional scale could be accurately simulated. Three times border irrigation experiments at regional scale were performed to validate the proposed model in Mawan Irrigation District, located in Dongying City, Shandong Province. Soil samples were collected at 4 depths from the top, middle, and bottom of the border field to analyze soil bulk density, soil particle size distribution, and soil moisture. The soil hydraulic parameters were transformed from the abovementioned soil properties using the Rosetta model. The relative elevation values of the border bottom were observed using a water level gauge. The surface flow depth was measured using water depth measuring devices, which were placed at every observation point before the irrigation was initiated. The surface flow depth was used to estimate Manning's roughness coefficient. And unit discharge, border length, and border width were observed in March 2012, November 2012, and March 2013. The validation results showed that the proposed model could well simulate regional scale border irrigation processes, and presented very good modeling accuracy. Specifically, the relative errors between the measured and simulated values by the proposed stochastic parameter irrigation model were 9.95%-12.23% and 8.39%-10.21% for irrigation quota and field water utilization coefficient, respectively. By contrast, the relative errors of irrigation quota and field water utilization coefficient based on the existing deterministic parameter irrigation models were 14.15%-16.78% and 13.87%-15.88%, respectively. Additionally, the cumulative probability distribution trends of average soil moisture after irrigation between the measured and simulated values present the satisfactory performance. Thus, the proposed model overcomes the shortcomings of existing models and provides a useful numerical analysis tool for the management and design of regional scale border irrigation system. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Infiltration
Controlled terms:Computer simulation - Flow of water - Hydraulics - Irrigation - Iterative methods - Moisture - Monte Carlo methods - Numerical methods - Numerical models - Particle size - Particle size analysis - Probability distributions - Soil moisture - Soil surveys - Soils - Stochastic models - Stochastic systems - Water levels
Uncontrolled terms:Cumulative probability distribution - Irrigation performance - Manning's roughness coefficient - Non-linear algebraic system - Parameters - Simulation and validation - Spatial variability - Surface-subsurface water flows
Classification code:483.1 Soils and Soil Mechanics - 631.1.1 Liquid Dynamics - 632.1 Hydraulics - 723.5 Computer Applications - 821.3 Agricultural Methods - 921 Mathematics - 921.6 Numerical Methods - 922.1 Probability Theory - 922.2 Mathematical Statistics - 951 Materials Science - 961 Systems Science
Numerical data indexing:Percentage 1.39e+01% to 1.59e+01%, Percentage 1.42e+01% to 1.68e+01%, Percentage 8.39e+00% to 1.02e+01%, Percentage 9.95e+00% to 1.22e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.001
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 33>
Accession number:20172803930306
Title:Vibration analysis and improvement for frame of 4SY-2.9 typed rape windrower
Authors:Jiang, Yajun (1); Liao, Yitao (1, 2); Qin, Chuan (1); Guan, Zhuohuai (1); Liao, Qingxi (1, 2)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China; (2) Collaborative Innovation Center for Oil Crops in South China, Changsha; 410128, China
Corresponding author:Liao, Qingxi(liaoqx@mail.hzau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:53-60
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In China, the rape harvesting mechanization level is low and traditional manual harvesting is so poor, so it is necessary to develop rape windrower to improve productivity and reduce cost. The pros and cons of the frame design play an important role on the comfort and working reliability of the windrower machine manipulation. The frame of 4SY-2.9 typed rape windrower is the base and bears the load of whole assembly, and during the rape windrower working, the exciting vibrations from cutter and the conveyor belt spring tooth will cause the rape windrower to vibrate. Because those excitation frequencies were closed to or overlapped the natural frequencies of the rape windrower, the frame of 4SY-2.9 typed rape windrower will produce resonance seriously. To improve the quality of laying, reducing the vibration amplitude of the frame of rape windrower is a feasible way, and the finite element method will solve this problem by using structural modal analysis to get the dynamic characteristics of the frame structure. In order to solve the problem of the large amplitude of the rack caused by the random exciting force produced by the movement of various parts of the machine, in this paper, we modeled the rack and imported the model in ANSYS Workbench to work out the frequency and vibration mode of the rack under the free modal, and we verified the accuracy of the finite element model through the contrast of the modal test and the simulation analysis results. It was found that the relative error between the 2 results was in a reasonable range, so the rationality of frame modal analysis was verified. Based on the analysis of the characteristics of the external excitation frequency of the frame and the simulation results, the design scheme was put forward, which was increasing the frame arch structure, and the simulation experiment on the pipe thickness and installation position of arch was carried out. The optimized rack's first-order modal frequency was adjusted to 15.339 Hz, so that it avoided the excitation frequency of the conveyor belt spring tooth and the cutter effectively which could cause the frame resonance. Through the finite element statistics analysis on the optimized model of the frame, the result showed that the strength of the frame met the requirements. Windrower on no-load condition collected acceleration time-domain signal of the biggest deformation point of longitudinal beam, and obtained the fast fourier transform power spectral analysis diagram under the condition with and without the installation of the arch. The test results showed that the amplitude along X direction at the largest peak point of test point decreased by 71.47%, the amplitude along Y direction was reduced by 70.60%, and the amplitude along Z direction was reduced by 70.21%. Field experiments showed that 4SY-2.9 typed rape windrower had a good operation performance with a good throughput capacity and a high work efficiency, and achieved an orderly intermediate strip paving. The paving width met the requirement of the working width of the collecting sheller. After cut down and dried, the average paving width of rapeseed stalks was 1 674 mm, the average stubble height of rapeseed stalks was 330 mm, and the average stack height of rapeseed stalks was 603 mm. The optimized rape windrower frame had a good dynamic performance, and the field operation effect could meet the requirement of the actual production. This research may provide references for the design and improvement of the similar broad frames. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Finite element method
Controlled terms:Arches - Belt conveyors - Conveyors - Fast Fourier transforms - Machinery - Modal analysis - Oilseeds - Optimization - Pavements - Productivity - Quality control - Spectrum analysis - Structural design - Testing - Time domain analysis - Vibration analysis
Uncontrolled terms:Dynamic characteristics - External excitation frequency - Frame - Operation performance - Power spectral analysis - Rape windrower - Throughput capacities - Vibrations
Classification code:408.1 Structural Design, General - 408.2 Structural Members and Shapes - 692.1 Conveyors - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 921 Mathematics
Numerical data indexing:Frequency 1.53e+01Hz, Percentage 7.02e+01%, Percentage 7.06e+01%, Percentage 7.15e+01%, Size 1.67e+00m, Size 3.30e-01m, Size 6.03e-01m
DOI:10.11975/j.issn.1002-6819.2017.09.007
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 34>
Accession number:20172803930302
Title:Performance analysis and experiment of cup-belt type patato seed-metering device with flow deflector
Authors:Lü, Jinqing (1); Wang, Yingbo (1); Li, Zihui (1); Dui, Han (1); Liu, Zhongyuan (1); Li, Jicheng (1); Sun, He (1); Peng, Manman (1)
Author affiliation:(1) Department of Engineering, 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:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:19-28
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to enhance seeding accuracy and seeding quality of potato, this paper analyses and tests the bouncing and casting process of the cup-belt type potato seed-metering device and the performance of flow deflector. The cup-belt type potato seed-metering devices have the problems such as the nonuniformity of plant spacing, and the higher replay rate and missing rate due to different casting angle, casting speed, casting height and potato bouncing when contacting with furrow. This paper contains the main structure and working principle of cup-belt type potato seed-metering device, and the working principle of the flow deflector is that potato drops out from seed-metering device to the deflector, and then flows along the surface. The flow deflector can reduce longitudinal distance that potato drops into furrow to make the form of potato seed in approximately one column. Flow deflector can also reduce the horizontal velocity of potato seed to decrease the distance of potato dropping into furrow. During the sowing process of seed-metering device, in addition to the contact with the flow deflector, bouncing after contact with soil will also have an influence on seeding results. In the event of seed bounce, the images of bounce process have spatial properties, a circular point uniform density of position of potato in furrow after bounce was formed, each bounce direction has the same possibility after jumping, and the displacement of potato after bounce is inconsistent. The above phenomenon will lead to a higher coefficient of variation for sowing spacing, and a lower qualified rate of seeding. The process of irregular bounce will also increase the replay rate and missing rate. This paper also obtains the main factors that influence bounce distance through the kinematic analysis of casting and bouncing process during potato seeding. The field experiment was carried out; the rotational speed of the driving pulley, the forward speed of the device, and the seed casting height were taken as the experiment factors, and the coefficient of variation of row spacing, the missing rate and the replay rate as the test indices. The test was implemented in Heilongjiang Academy of Agricultural Sciences in September, 2015 and May, 2016. Potato in this test was prepared by Northeast Agricultural University, the shape index of potato was 205.8, and the average mass of potato was 24.38 g. The experimental data were processed and optimized by software Design-Expert 8.0.6. The test result showed the primary and secondary order of influencing factors for each test index. For the coefficient of variation of row spacing, the order was the forward speed of the device, the rotational speed of driving pulley and the casting height of potato seed. For the missing rate, the order was the rotational speed of the driving pulley, the forward speed of the device and the casting height of potato seed. The order for the replay rate was as follows: The rotational speed of the driving pulley, the forward speed of the device and the casting height of potato seed. And results also showed that the coefficient of variation of row spacing was 12.5%, the missing rate was 2.21% and the replay rate was 3.56%, when the rotational speed of driving pulley was 42 r/min, the forward speed of the device was 1.2 m/s and the potato casting height was 640 mm. This device had a good seeding effect compared with the national standards. Through the performance analysis of flow deflector, the theoretical analysis of the casting progress and bouncing process of potato, and the field experiment, it has been verified that the cup-belt type potato seed-metering device which has been optimized can enhance the potato seeding accuracy and sowing effect. This research not only provides the theoretical and technical reference for improvement and optimization of potato seed-metering devices, but also other precision sowing seed-metering devices. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Seed
Controlled terms:Agriculture - Crops - Drops - Experiments - Machinery - Pneumatic materials handling equipment - Pulleys - Software design - Software testing - Soil testing - Speed - Testing
Uncontrolled terms:Agriculture machinery - Bounce - Flow deflector - Potato - Row spacing - Seed metering devices
Classification code:483.1 Soils and Soil Mechanics - 691.1 Materials Handling Equipment - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 901.3 Engineering Research
Numerical data indexing:Mass 2.44e-02kg, Percentage 1.25e+01%, Percentage 2.21e+00%, Percentage 3.56e+00%, Rotational_Speed 4.20e+01RPM, Size 6.40e-01m, Velocity 1.20e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.09.003
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 35>
Accession number:20172803930309
Title:Analysis of fluid-structure interaction characteristics for impeller of residual heat removal pump
Authors:Yin, Tingyun (1); Pei, Ji (1); Yuan, Shouqi (1); Wang, Wenjie (1)
Author affiliation:(1) National Research Center of Pumps, Jiangsu University, Zhenjiang; 212013, China
Corresponding author:Pei, Ji(jpei@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:76-83
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, nuclear power has drawn increased attention because of its high efficiency and low pollution. Thus, a rising number of nuclear power stations are being constructed. The safety of nuclear station operations is mainly guaranteed by the residual heat removal system. Residual heat removal pumps (RHRP) are operated when the nuclear main pump stops working and the nuclear station needs to be maintained. The RHRP works in a complex environment, and its work status directly affects the performance of the entire plant. To ensure the reliability of the RHRP, the vibration characteristics of the rotor were analyzed using fluid-structure interaction theory. Stress and deformation analysis by partitioned solution for an impeller in a moving fluid was performed, and modal analysis of the impeller by monolithic solution was conducted in still fluid. For the partitioned method, there are two strategies for coupled solutions of dynamic fluid and structure interaction, one-way coupling and two-way coupling. Two-way coupling is typically used for large structural deformations. One-way coupling is suitable for the small structural deformation cases. In pump machinery, the impeller vibration caused by unsteady flow results in small deformations. Additionally, the feedback of the impeller motion onto the flow is small and therefore, can be neglected for most cases. Consequently, one-way coupling has been chosen, in which dynamic forces are transferred to the structure through the interface in a single direction at every time step. To understand the influence of the impeller shroud thickness on the resulting vibration characteristics, three impeller modifications were investigated and compared to the initial geometry under different flow rates. Moreover, five commonly used materials for an impeller were also evaluated. The three-dimensional turbulent flow was modeled utilizing a SST k-ω turbulence model, and the numerical results were verified by the experimental data. The results showed that due to local structural differences between the pumps used in the numerical calculation model and the test measurement, as well as other effects, such as mesh quality, it was inevitable that there would be differences between the numerical calculation and the test measurements. However, the overall external characteristics of the numerical simulation were generally consistent with the performance of the test measurements, indicating that the flow-field calculation model can accurately predict its performance. By comparing with impellers adapted from four other materials and different shroud thicknesses, the vibration modes of the impellers were basically same for each order; however, the natural frequencies differed to some extent. The first order frequency of original impeller rotor was 394.17 Hz at hot condition and increased by 2.28% compared with cold condition, which was higher than blade passing frequency. Natural frequency of 1Cr13MoS was the highest among employed materials for each order mode, while ZG225-450 was the lowest. At design and off-design flow rates, the stress and displacement fields were similar. The displacement grew from the hub to the outer diameter, and each blade passage had a local maximum on the rear shroud. Moreover, the higher equivalent stress values can be observed in the junction between blade and shroud. Under three operating points, the peak values of stresses occurred in the middle of the junction between shroud and blade pressure side. Decreasing the head caused a significant reduction at the beginning of the blade passage. The stresses along defined paths were almost independent of the front shroud thickness, but peak values could be significantly reduced with a thicker rear shroud. The trendy of stress distribution between hot and cold condition was basically same. However, stress of hot condition was higher than cold one. Especially nearby the leading edge of the impeller, stress of hot condition increased more than 300%, compared to cold one. The results provide a theoretical basis for improving system performance and further study for more complicated dynamic analysis and fatigue analysis. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Vibration analysis
Controlled terms:Computational fluid dynamics - Deformation - Enzyme kinetics - Fluid structure interaction - Impellers - Machinery - Modal analysis - Natural frequencies - Nuclear energy - Nuclear fuels - Numerical models - Pumps - Reliability theory - Rotors - Structural analysis - Structural design - Turbulence models
Uncontrolled terms:K-Omega turbulence model - Numerical calculation model - Residual heat removal pumps - Residual heat removal systems - Shroud thickness - Stress and displacement fields - Three-dimensional turbulent flow - Vibration characteristics
Classification code:408.1 Structural Design, General - 601.2 Machine Components - 618.2 Pumps - 631.1 Fluid Flow, General - 723.5 Computer Applications - 921 Mathematics - 922.2 Mathematical Statistics - 932.2 Nuclear Physics
Numerical data indexing:Frequency 3.94e+02Hz, Percentage 2.28e+00%, Percentage 3.00e+02%
DOI:10.11975/j.issn.1002-6819.2017.09.010
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 36>
Accession number:20172803930330
Title:Hydrogen production technology by solid oxide electrolysis cell with symmetrical eletrode at intermediate temperature
Authors:Lu, Yuzheng (1); Wang, Jun (1); Jiang, Chuan (1); Yang, Song (1); Zhang, Yaoming (1)
Author affiliation:(1) Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology, School of Energy and Environment, Southeast University, Nanjing; 210018, China
Corresponding author:Wang, Jun(wj-jw@seu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:237-242
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Efficient, clean and sustainable energy become the focus of current energy research. Although solar power, wind power and tidal power are promising renewable energy sources, they are site-specific and intermittent, which is not suitable for continuous energy supply. Hydrogen, which is transportable and storable, could serve as an attractive option for energy carrier. Nowadays, it is important to develop a technology for producing hydrogen with high efficiency and low pollution. Solid oxide electrolysis cells (SOEC) based on solid oxide fuel cell (SOFC) technology provides a solution in which hydrogen is produced from water and oxygen is the only by-product. Hybrid hydrogen production integrating solar energy and solid oxide electrolysis cell (SOEC) is an energy conversion device with high performances. In this paper, a hydrogen production system was designed based on intermediate temperature solid oxide electrolysis cell. Solar energy was utilized as the only prime energy sources for the system. The demands of thermal energy and electricity for the hydrogen production were supplied by solar dish and photovoltaic subsystem, respectively and SOEC was the key component of the hybrid system. A new type of solid oxide electrolysis cell, having the symmetrical electrode structure, was proposed and studied in this paper, which was based on the solid oxide electrolysis cell with the conventional structure of anode-electrolyte-cathode. The chemical precipitation method was used to produce the electrolyte material, Ce<inf>0.8</inf>Sm<inf>0.2</inf>O<inf>1.9</inf>-Na<inf>2</inf>CO<inf>3</inf>(NSDC), and to find out the specific electrode material compatible well with the NSDC, the Ni<inf>0.8</inf>Co<inf>0.15</inf>Al<inf>0.05</inf>LiO<inf>2-δ</inf>(NCAL). X-ray diffraction (XRD) method and scanning electron microscope (SEM) were utilized in this paper for the description as well as the analysis of performance relating to the materials produced. The results showed that the NSDC also has a fluorite structure, the particle size of which was in the range from 30 to 80 nm. Further, the solid oxide electrolysis cell was fabricated though using the NSDC and NCAL obtained earlier. Under SOEC mode and current density of 0.376 A/cm<sup>2</sup>, the electrolyte voltage was 1.5 V at 823 K. The results of electrochemical experiments showed that a good performance of hydrogen production can be achieved by using the single cell in the electrolysis mode. Moreover, the electrochemical performance still remained in a good condition even the electrodes were switched. According to the theoretical analysis and the experimental results, it can be demonstrated that this new type of cell shows a good structural symmetry. In addition, intermediate-temperature system can promote electrode activity and lessen the over potential. Therefore, it is possible to increase the electric current density and consequently decrease the polarization losses at intermediate temperature, which improves the hydrogen production density and the electrolysis efficiency. Thus, this new hybrid hydrogen production system is advantages from both thermodynamic and kinetic standpoints. The hybrid hydrogen production integrating solar energy operation at intermediate temperature is much more efficient than low-temperature water electrolysis systems such as alkaline water electrolysis and solid polymer electrolyte water electrolysis. The obstacle for the development of SOEC technology is the cost. Fortunately, the cost of this new structure of SOEC with the symmetrical electrode is very low. It is our hope that the results we report here may pave a way for SOEC industrialization. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Solid electrolytes
Controlled terms:Alkalinity - Anodes - Cathodes - Electric losses - Electrochemical electrodes - Electrodes - Electrolysis - Electrolytes - Electrolytic cells - Energy efficiency - Hybrid systems - Hydrogen - Hydrogen production - Low temperature production - Polyelectrolytes - Precipitation (chemical) - Pressure - Produced Water - Regenerative fuel cells - Renewable energy resources - Scanning electron microscopy - Solar energy - Solar power generation - Solid oxide fuel cells (SOFC) - Temperature - Tidal power - Wind power - X ray diffraction
Uncontrolled terms:Alkaline water electrolysis - Chemical precipitation method - Electrochemical experiments - Electrochemical performance - Hydrogen production systems - Hydrogen production technology - Intermediate temperatures - Solid polymer electrolyte water electrolysis
Classification code:522 Gas Fuels - 525.1 Energy Resources and Renewable Energy Issues - 525.2 Energy Conservation - 611.2 Tidal Power Plants - 615.2 Solar Power - 615.8 Wind Power (Before 1993, use code 611 ) - 641.1 Thermodynamics - 657.1 Solar Energy and Phenomena - 702.2 Fuel Cells - 714.1 Electron Tubes - 801.1 Chemistry, General - 801.4.1 Electrochemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 815.1.1 Organic Polymers - 921 Mathematics - 931.1 Mechanics
Numerical data indexing:Current_Density 3.76e+03A/m2, Size 3.00e-08m to 8.00e-08m, Temperature 8.23e+02K, Voltage 1.50e+00V
DOI:10.11975/j.issn.1002-6819.2017.09.031
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 37>
Accession number:20172803930304
Title:Adaptive fuzzy-PID control of accurate orientation for auto-detect seedling supply device
Authors:Liu, Jiaodi (1, 2); Cao, Weibin (1); Xu, Hongzhen (3); Tian, Dongyang (1); Jiao, Haobo (1); Ouyang, Yineng (4)
Author affiliation:(1) College of Machine and Electrical Engineering, Shihezi University, Shihezi; 832000, China; (2) The State Key Laboratory of Mechanical Transmissions, Chongqing University, Chongqing; 404100, China; (3) Xinjiang Tianye Company Limited, Shihezi; 832000, China; (4) College of Science, Shihezi University, Shihezi; 832000, China
Corresponding author:Cao, Weibin(wbc828@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:37-44
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There is more serious seedling leakage phenomenon for duckbill-type automatic transplanter. When the seedlings in plug tray are lacked or the picking seedling machinery fails to pick seedling or the trajectory is inaccurate, throwing seedling to duckbill planter will cause cavity phenomenon on the surface of soil. Current research has focused on seedlings detection out of plug tray, aiming to provide guidelines in picking seedling mechanism's work regularity. However, it cannot resolve the problems that picking seedling needle clamp fails to grip seedlings into duckbill planter, which leads to seedling trajectory deviation. In this paper, a new auto-detect seedlings device suitable for automatic transplanting machine was designed in order to solve the problems above. Seedling positioning detection control system was analyzed and studied systematically. Different from general control system of transplanting machine, which was commonly simple closed-loop control, a method was developed, which adopted the self-adaptation fuzzy-PID (proportion, integral, derivative) control algorithm. It could control stepping motor angle speed firmly, improve response speed to angle speed, and control seedlings positioning accurately on automatic detection system. The mathematical model of the stepping motor velocity control transfer function was developed, and the adaptive fuzzy-PID controller and the fuzzy rules were designed. The mathematical model of angular speed control of stepping motor was established through MATLAB Simulink module based on fuzzy-PID controller of stepper motor system. The control model took step signal as excitation signal, and the adaptive fuzzy-PID control and PID control simulation experiments showed that when the system exerted incentive through step signal, the response time of PID control was 7 s, the system response was slow, and the shock with a super adjustable volume of 0.1 appeared. Through adjusting PID controller parameter and increasing proportion coefficient, the system response time was shortened to 2.2 s, the system response speed obviously sped up, and the shock did not appear. But, PID controller parameter adjustment was offline, and the system load mutation or tough working environment for seedlings detection system would be prone to all kinds of interference. And it may not quickly be adjusted to the steady state values to fill the gaps with seedlings detection system. Response time of adapted fuzzy-PID was 0.12 s and the stepping motor system quickly reached the steady-state value of the step response. It showed that the angular velocity control of stepping motor was stable and the angle change was fast, which could meet the positioning requirements of seedlings conveying. When the auto-detect seedlings device load mutated or the expected value of stepping motor speed changed, the stepping motor could fast response, and the seedlings could fill the gaps timely and be planted normally, at the same time the seedling which will fill the gap will be conveyed to the required position. The experiment result of automatically filling the gaps with seedlings showed that the actual seeding frequency of 2ZXM-2 automatic membrane transplanting machine was 40-60 seedlings/min. When seeding frequency was more than 60 seedlings/min, there existed matching error between seedlings manipulator and plant duckbill. It could increase the leakage rate of seedlings. When the frequency was lower than 40 seedlings/min, the planting efficiency was low and at the same time it could make planting distance of transplanting seedling larger. The seeding frequency was 40, 50 and 60 seedlings/min in test, and the success rate of filling the gaps with seedlings was 100%, 100%, and 95.8%, respectively. As long as the optical fiber sensor detected slight signal, the stepping motor responded quickly based on adaptive fuzzy-PID control system, and the control system of filling the gaps with seedlings could automatically fill the gaps with seedlings accurately and timely. This provides a new method to solve the problem of seedlings leakage of automatic transplanting machine in field. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Adaptive control systems
Controlled terms:Adaptive optics - Agricultural machinery - Angular velocity - Control - Control systems - Controllers - Electric control equipment - Experiments - Filling - Functions - MATLAB - Optical fibers - Partial discharges - Problem solving - Proportional control systems - Response time (computer systems) - Seed - Speed - Stepping motors - Three term control systems - Velocity control
Uncontrolled terms:Adaptive fuzzy pid controllers - Automatic detection systems - Automatic filling seedlings - General control systems - Positioning control - Positioning detection - System response speed - Transplanting machine
Classification code:691.2 Materials Handling Methods - 701.1 Electricity: Basic Concepts and Phenomena - 705.3 Electric Motors - 731.1 Control Systems - 731.3 Specific Variables Control - 732.1 Control Equipment - 741.1 Light/Optics - 741.1.2 Fiber Optics - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 921 Mathematics
Numerical data indexing:Percentage 1.00e+02%, Percentage 9.58e+01%, Time 1.20e-01s, Time 2.20e+00s, Time 7.00e+00s
DOI:10.11975/j.issn.1002-6819.2017.09.005
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 38>
Accession number:20172803930316
Title:Increasing soil nitrogen fixation capacity and crop yield of rice-rape rotation by straw returning
Authors:Zhang, Dan (1); Fu, Bin (2); Hu, Wanli (2); Zhai, Limei (1); Liu, Hongbin (1); Chen, Anqiang (2); Gai, Xiapu (1); Zhang, Yitao (1); Liu, Jian (3); Wang, Hongyuan (1)
Author affiliation:(1) Ministry of Agriculture Key Laboratory of Nonpoint Source Pollution Control, Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China; (2) Institute of Agricultural Environment and Resources, Yunnan Academy of Agricultural Sciences, Yunnan; 650205, China; (3) College of Plant Nutrition, Pennsylvania State University, PA; 16802, United States
Corresponding author:Wang, Hongyuan(wanghongyuan@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:133-140
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Recently, crop straws returning to field has been vigorously proposed as an effective strategy to promote agricultural sustainability in China. However, there were few studies revealing the effects of straw return on rice (Oryza Sativa) - rape (Brassica campestris) rotation systems in Southwest China, especially lacking contrastive research about different crop straws. To explore the effects of straw incorporation on crop yield and soil nitrogen (N) retention of rice-rape rotation system, a field experiment was conducted from 2013 to 2015 in Yunnan Province. Specifically, the experiment consisted of 4 treatments: No fertilizer (CK), chemical fertilizer (CF), chemical fertilizer plus maize straw (CFMS), and chemical fertilizer plus broad bean straw (CFBS). Crop yield, soil N content, soil microbial biomass carbon (SMBC), soil microbial biomass nitrogen (SMBN), and some other soil physicochemical properties were determined after rice or rape harvest. The results showed that straw incorporation (CFMS and CFBS) considerably increased crop yield and total biomass compared with the CF, and the yield and biomass of rape were increased by 28.6%-62.1% and 5.2%-20.2%, respectively, and those of rice were increased by 6.2%-35.8% and 35.7%-87.4%, respectively. In particular, CFMS produced the highest crop yield (4.2-4.7 t/hm<sup>2</sup>for rape and 11.0-12.2 t/hm<sup>2</sup>for rice), and CFMS increased the rape and rice yield by 16.7%-17.5% and 24.5%-27.9%, respectively, compared with CFBS. In consistent with the effects on crop yield, straw incorporation effectively increased the N content of rice and rape, and CFMS and CFBS increased the N content by 14.5%-20.2% and 5.2%-9.0% for rape, respectively, and 68.3%-87.4% and 35.7%-55.0% for rice, respectively, relative to the CF. In addition, CFMS significantly increased the N content (161.0-185.3 kg/hm<sup>2</sup>for rape and 219.0-243.1 kg/hm<sup>2</sup>for rice) compared with CFBS (153.3-162.1 kg/hm<sup>2</sup>for rape and 176.6-201.0 kg/hm<sup>2</sup>for rice) (P<0.05). Furthermore, the SMBC and SMBN under straw incorporation were both increased significantly compared with CK (P<0.05), and they were ranked in such order: CFMS>CFBS>CF>CK. There was no significant difference in the soil pH value, total N, soil organic matter (SOM) and soil C/N among these 4 treatments (P>0.05) because of the relatively short experimental period (only lasting for 2 years). Generally, the soil microbial entropy and soil microbial biomass C/N (SMB C/N) could quickly respond to straw incorporation compared with the highly stable soil C/N. Nitrate N was the main component of inorganic N in soil, and soil residual N after crop was harvested was significantly decreased under straw incorporation (P<0.05), which declined by 11.6%-55.0% for CFMS and 13.7%-52.3% for CFBS compared with the CF (45.4 mg/kg). Rainfall mainly occurred during rice growing season (from May to October) in Southwest China, which had a high potential to cause N losses. However, the significant reduction of residual N in soil by straw incorporation after rape was harvested could probably lead to a lower potential of N loss in rice growing season. We conclude that the incorporation of straw into soil can increase crop yield and crop N uptake, improve soil N immobilization potential and reduce risks of N loss in the rice-rape rotation in Southwest China. Particularly, the incorporation of maize straw demonstrates greater advantages in yield increase and N retention than bean straw in actual production. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:51
Main heading:Soils
Controlled terms:Agriculture - Biomass - Crops - Fertilizers - Harvesting - Nitrates - Nitrogen - Nitrogen fixation - Nobelium - Organic carbon - Rotation - Straw
Uncontrolled terms:Agricultural sustainability - Crop yield - Nitrate nitrogen - Soil microbial biomass - Soil microbial biomass c - Soil microbial biomass carbons - Soil microbial biomass nitrogens - Soil physico-chemical properties
Classification code:483.1 Soils and Soil Mechanics - 622.1 Radioactive Materials, General - 802.2 Chemical Reactions - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics
Numerical data indexing:Age 2.00e+00yr, Percentage 1.16e+01% to 5.50e+01%, Percentage 1.37e+01% to 5.23e+01%, Percentage 1.45e+01% to 2.02e+01%, Percentage 1.67e+01% to 1.75e+01%, Percentage 2.45e+01% to 2.79e+01%, Percentage 2.86e+01% to 6.21e+01%, Percentage 3.57e+01% to 5.50e+01%, Percentage 3.57e+01% to 8.74e+01%, Percentage 5.20e+00% to 2.02e+01%, Percentage 5.20e+00% to 9.00e+00%, Percentage 6.20e+00% to 3.58e+01%, Percentage 6.83e+01% to 8.74e+01%
DOI:10.11975/j.issn.1002-6819.2017.09.017
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 39>
Accession number:20172803930336
Title:Effect of transport vibration in different levels of road on Hamimelons (Cucumis melo var. saccharinus) quality
Authors:Zeng, Yuanyuan (1); Zhou, Ran (1); Jiang, Chunqi (1); Wu, Qiong (1); Xin, Qi (1)
Author affiliation:(1) College of Food Science and Technology, Shanghai Ocean University, Shanghai; 201306, China
Corresponding author:Zhou, Ran(rzhou@shou.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:282-289
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Transport from origin area to main consumption area is needed for improving the economic profit of Hami melon (Cucumis melo var. saccharinus). Transport vibration has an important adverse impact on the ripening of Hami melon. Fruit ripening changes are closely related to cell membrane lipid oxidation and reactive oxygen metabolism process. In order to study the effect of different levels of road transport vibration on active oxygen metabolism and membrane lipid oxidation of Hami melons, the vibration environments of the semi-trailer in highways, arterial roads, secondary roads and tertiary roads were simulated and relative indices were measured. In this study, Huajun semi-trailer was used to measure transport vibration, and the data were collected once every 3 minutes for 2 seconds as the semi-trailer was at the speed of 61-90 km/h. Then the data were used to drive a shaker to simulate the transport vibration. The melons were packaged with net packages and placed in corrugated fiberboard containers, and were treated under transport vibration of different grades of roads with the untreated as control samples. During the vibration treatment, the environmental temperature was 23℃. After treatments, all of the melons were stored at 23℃. The indices included respiration rate, firmness, relative electric conductivity, lipoxygenase (LOX), malondialdehyde (MDA) and reactive oxygen species (ROS). The results showed that after the storage of 28 days, the respiration rate of Hami melons under the vibration treatment in highways, arterial roads, secondary roads and tertiary roads was 1.31, 1.61, 2.03 and 2.21 times that of the control group, respectively, and the difference was significant (P<0.05). The firmness of Hami melons under the vibration treatment in highways, arterial roads, secondary roads and tertiary roads was 15.27%, 35.27%, 60.50% and 77.47%, lower than that of the untreated, respectively, and the difference was significant (P<0.05). The electric conductivity of Hami melon with different road vibration was significantly higher than that of the control. And about the decay area, the Hami melons of the control group were more intact, while the vibration group had different degrees of decay, of which the melon decay areas were 0-5% for transport vibration treatment groups of highways and arterial roads, and 16%-25% for transport vibration treatment groups of secondary roads and tertiary roads. It was clear that the vibration accelerated the fruit softening, accelerated the cell membrane lipid oxidation, promoted the activity of LOX, and accelerated the process of free radical reaction, so that the ROS content continued to increase, which resulted in more MDA, and caused the cell membrane to be damaged and the relative conductivity to increase. The influence of the transport vibration of tertiary roads and secondary roads on Hami melons was more significant than that of highways and arterial roads. And ROS content of Hami melons treated by transport vibration of tertiary roads was higher than that of the roads of other grades (P<0.05), and the effect of tertiary roads and secondary roads on the cell membrane of Hami melon was more significant (P<0.05), which showed that with the increase of vibration power spectral density, the quality of Hami melon was affected by the transport vibration. The results provide a reference for finding ways to reduce the influence of transport vibration on the quality of melon. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Transportation
Controlled terms:Cell membranes - Cells - Corrugated containers - Cytology - Digital storage - Electric conductivity - Electric conductivity measurement - Free radical reactions - Fruits - Ionization of gases - Lipids - Membranes - Metabolism - Oxidation - Oxygen - Physiology - Power spectral density - Quality control - Reaction kinetics - Roads and streets - Spectral density - Truck transportation - Value engineering
Uncontrolled terms:Corrugated fiberboards - Different levels of road - Environmental temperature - Hami melons - Reactive oxygen species - Respiration rate - Vibration - Vibration environment
Classification code:406.2 Roads and Streets - 432.3 Cargo Highway Transportation - 461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 694.1 Packaging, General - 701.1 Electricity: Basic Concepts and Phenomena - 722.1 Data Storage, Equipment and Techniques - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.4 Agricultural Products - 911.5 Value Engineering - 913.3 Quality Assurance and Control - 942.2 Electric Variables Measurements - 951 Materials Science
Numerical data indexing:Age 7.67e-02yr, Percentage 0.00e+00% to 5.00e+00%, Percentage 1.53e+01%, Percentage 1.60e+01% to 2.50e+01%, Percentage 3.53e+01%, Percentage 6.05e+01%, Percentage 7.75e+01%, Time 1.80e+02s, Time 2.00e+00s, Velocity 1.69e+01m/s to 2.50e+01m/s
DOI:10.11975/j.issn.1002-6819.2017.09.037
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 40>
Accession number:20172803930310
Title:Prediction method for spatial distribution of corn borer based on unmanned aerial vehicle images and semivariance function
Authors:Wu, Caicong (1); Hu, Bingbing (1); Zhao, Ming (1); Kou, Zhihong (1); Zhang, Lijun (2)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (2) Shenbeixinqu Agro-Tech Extension Center, Shenyang; 110121, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:84-91
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Serious pest of Asiatic corn borer in China would lead to yield reduction by more than 30%. Precise prediction and variable rate prevention of corn borer are required for cite-specific management nowadays, since too much chemical usage lowers the quality of agricultural product as well as deteriorates the pollution of agricultural environment. The farmers producing silage corn are in face of serious problem of sustainable development. Semivariance function for spatial distribution prediction is the basis of cite-specific management for corn borer. The objective of the research was to find the optimum semivariance function and prediction model for Asiatic corn borer in Shenyang. A circular area around Dayanghe Village with a radius of 2 km was selected as core experimental area. Five other villages were located around Dayanghe Village. Silage corn was planted by China Huishan Dairy Holding Company Limited in the fields among the 6 villages. Grain corn was planted in some small fields around the houses by farmers. PHANTOM 4, unmanned aerial vehicle (UAV) with the camera of FOV 9420 mm, was used to collect the high resolution image. The ground resolution was 0.04 m. The villages, corn straws, and corn fields were interpreted through the UAV images. Both percentage of pest damaged plants (91 sampling points) and percentage of overwintering worms were investigated manually in 2016. And the villages in the research area were divided into grids. The life cycles of Asiatic corn borer, the impact factors of spread, and the spatial variability of percentage of pest damaged plants were studied. Quantity of worm source and spread distance were the key impact factors of the spread behavior of corn borer. Only the larvae and adults have the spread capability, and the adults of corn borer could spread for a large area. The results showed that the spatial variability of pest damaged plants was significant, whose standard deviation was 12.03% and coefficient of variation was 47.38%. It proved that variable rate fertilization for corn borer cite-specific management was necessary. The distribution of percentage of pest damaged plants fitted log-normal distribution, whose K-SP was 0.084. Furthermore, zero-order exponential model was the optimum semivariance function for the fitting of pest damaged plants distribution by cross-validation. Correlation coefficient between overwintering insects and pest damaged plants was 0.61. Therefore, the spatial distribution maps of Asiatic corn borer could be produced through investigating the percentage of pest damaged plants and Kriging interpolation with zero-order exponential model. Only worm sources could not precisely predict the distribution and influence degree of corn borer because of numerous complex impact factors. But the investigation of overwinter worm sources was meaningful for occurrence degree for the current year. Compared with traditional spraying in the research area, the dosage of variable rate spraying reduced by 28.1%, which supposed the spraying dosage of level Ⅱ was 70% of that of level Ⅲ. Therefore, the reduction of spraying dosage was obvious, and the variable rate spraying was valuable and should be encouraged. In conclusion, the technical route of this paper by using UAV and ground investigation, can be the implementation approach for cite-specific management of Asiatic corn borer, and can reduce pesticide waste and environmental pollution. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Spatial distribution
Controlled terms:Agricultural products - Agriculture - Environmental management - Forecasting - Image analysis - Interpolation - Normal distribution - Pest control - Pesticides - Pollution - Rural areas - Sustainable development - Unmanned aerial vehicles (UAV) - Vehicles - Waste management
Uncontrolled terms:Agricultural environments - Coefficient of variation - Corn borer - Environmental pollutions - Percentage of pest damaged plants - Semivariances - Spatial distribution map - Variable rate fertilization
Classification code:454.1 Environmental Engineering, General - 652.1 Aircraft, General - 803 Chemical Agents and Basic Industrial Chemicals - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 921 Mathematics - 921.6 Numerical Methods - 922.1 Probability Theory
Numerical data indexing:Size 4.00e-02m, Size 9.42e+00m, Percentage 1.20e+01%, Percentage 2.81e+01%, Percentage 3.00e+01%, Percentage 4.74e+01%, Percentage 7.00e+01%, Size 2.00e+03m
DOI:10.11975/j.issn.1002-6819.2017.09.011
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
<RECORD 41>
Accession number:20172803930303
Title:Design and experiment on seed flow sensing device for rapeseed precision metering device
Authors:Ding, Youchun (1); Yang, Junqiang (1); Zhu, Kai (1); Zhang, Lili (1); Zhou, Yawen (1); Liao, Qingxi (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:9
Issue date:May 1, 2017
Publication year:2017
Pages:29-36
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Precision seeding plays an important role in intelligent agricultural machinery development due to its advantages of saving seeds, reducing labor intensity, improving operation efficiency and increasing farmers' income. In the planting process, seed metering device is in a closed status and sowing quantity affects crop yield directly, and thus sowing quantity monitoring become one of the development trends in intelligent precision seeding. In recent years, various methods for precision seeding such as photoelectric sensor detection, high-speed photography, and capacitance sensing have been proposed to improve seeding performance for the corn, rice, soybean and other large seeds. Few studies have focused on the sensing method of small seeds such as rapeseed because of its small size, light weight and high frequency seeding. Thus, the development and application of monitoring technology about precision sowing for small seeds are limited. In this study, a seed flow sensing device for rapeseed precision metering device was designed and tested. Specifically, collision trajectory between rapeseed and PVDF (polyvinylidene fluoride) piezoelectric film was recorded and analyzed using high-speed photography and collision dynamics. These data provided a quantitative reference for the design of key structures in terms of the height of catheter, sloping angle of piezoelectric film, position of seed-output, etc. The sensing structure of sinking groove substrate and piezoelectric film was designed based on the analysis of characteristics of impact signal between rapeseed and piezoelectric film. The structure could limit the free oscillation amplitude of the piezoelectric film that could weaken the peak voltage of the free oscillation effectively. The decay time of impact signal was reduced from 9 to 1 ms, which improved the time resolution for high frequency seed flow detection and effectively eliminated the interference caused by mechanical vibration. The signal conditioning circuit turned weak signal into single pulse signal by signal amplification, half wave rectification, voltage comparison, and mono-stable triggering. Then, the real-time detection of seeding frequency and seeding quantity of rapeseed flow was obtained through the timing and counting function of the MCU (STC12C2052AD). Finally, these data were transmitted at a fixed time interval (1 s) by 2.4 GHz wireless transmission module to the monitoring display terminal, and the real-time display and storage of detection data (including the seeding frequency and the total seeding amount) were realized. Bench experiment consisted of two tests. One was carried out on the pneumatic precision metering device for rapeseed bench test. During the test, a seeding plate (40 holes) was set at a suitable speed such as 12, 18, and 24 r/min (seeding frequency was 8, 12, and 16 Hz), and the sensing device was installed under the metering device. After a period of seeding time, the detection seeding quantity, seeding time and actual seeding quantity were recorded by observing monitoring display terminal and by manual counting the seeds in the seeds collecting bag. Another test about high-rate seeding was carried out using microcomputer automatic counting instrument. During the test, seeding frequency was set as about 20, 24, 28, and 32 Hz, respectively by adjusting the vibration level, and then the detection of seeding quantity, the seeding time and the actual seeding quantity were obtained using a similar method of the first test. Tests of rapeseed precision metering device bench and high-rate seeding with counting instrument showed that the detection accuracy was not less than 99.5% by comparing detection seeding quantity and actual seeding quantity in the seeding frequency ranging from 8.1 to 32.9 Hz. In addition, the field experiment was carried out on precision joint planter of 2BYM8 for rapeseed driven by a LOVOL M704-BA tractor. The results indicated that the sensing device based on the composite sensing structure of sinking groove substrate and piezoelectric film sensing composite structure can detect the seed flow seeding frequency and seeding quantity, with the counting number being zero without seeding and the detection accuracy being not less than 99.1% under normal seeding. Besides, the mechanical vibration and dust had no effect on the sensing device. The piezoelectric rapeseed flow sensing device presented may facilitate metering quantity monitoring, loss sowing detection and reseeding. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Seed
Controlled terms:Agricultural machinery - Agriculture - Capacitance - Design - Digital storage - Electric rectifiers - High speed photography - Mechanization - Monitoring - Oilseeds - Photography - Piezoelectricity - Signal conditioning circuits - Vibrations (mechanical)
Uncontrolled terms:Collision - Development and applications - Half wave rectification - Polyvinylidene fluorides - Precision metering - Rapeseed flow - Sensing devices - Wireless transmi-ssion modules
Classification code:601 Mechanical Design - 701.1 Electricity: Basic Concepts and Phenomena - 722.1 Data Storage, Equipment and Techniques - 722.4 Digital Computers and Systems - 742.1 Photography - 746 Imaging Techniques - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931.1 Mechanics
Numerical data indexing:Frequency 1.60e+01Hz, Frequency 2.40e+09Hz, Frequency 3.20e+01Hz, Frequency 8.10e+00Hz to 3.29e+01Hz, Percentage 9.91e+01%, Percentage 9.95e+01%, Rotational_Speed 2.40e+01RPM, Time 1.00e+00s, Time 9.00e-03s to 1.00e-03s
DOI:10.11975/j.issn.1002-6819.2017.09.004
Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.
期刊信息
- 主管单位 中国科学技术协会
- 主办单位 中国农业工程学会
- 主编 朱明
- 总编/社长 王应宽
- 地址 北京朝阳区麦子店街41号
- 邮编 100125
- 电话 010－59197078/7077/7076
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微信公众号
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友情链接
- Bioresource Technology
- Industrial Crops and Products
- Biomass & Bioenergy
- Biosystems Engineering
- Aquacultural Engineering
- International Journal of Agricultural and Biological Engineering
- Journal of Irrigation and Drainage Engineering
- Paddy and Water Environment
- Journal of Agricultural Engineering
- Transactions of the ASABE
- Revista Brasileira de Engenharia Agricola e Ambiental
- Applied Engineering in Agriculture
- Engenharia Agricola
- AMA-Agricultural Mechanization in Asia Africa and Latin America
- 中华人民共和国农业农村部-MARA
- 中国科学技术协会CAST
- 国家新闻出版署
- 中华人民共和国科学技术部
- 国家自然科学基金委员会
- U.S. DEPARTMENT OF AGRICULTURE
- CIGR
- ASABE
- EurAgEng-European Society for Agricultural Engineers
- American Society of Agronomy
- Crop Science Society of America
- Soil Science Society of America
- 期刊界
- CNKI
- 万方数据
- 维普