<RECORD 1>

Accession number:20202108693825
Title:Effects of CO<inf>2</inf> concentration and temperature on leaf photosynthesis and water use efficiency in maize
Title of translation:CO<inf>2</inf>&#27987;&#24230;&#21644;&#28201;&#24230;&#23545;&#29577;&#31859;&#20809;&#21512;&#24615;&#33021;&#21450;&#27700;&#20998;&#21033;&#29992;&#25928;&#29575;&#30340;&#24433;&#21709;
Authors:Liu, Liang (1); Hao, Lihua (1); Li, Fei (1); Guo, Lili (1); Zhang, Xixi (1); He, Chunlin (1); Zheng, Yunpu (1)
Author affiliation:(1) School of Water Conservancy and Hydroeletric Power, Hebei University of Engineering, Handan; 056038, China
Corresponding author:Zheng, Yunpu(zhengyunpu_000@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:122-129
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Elevated atmospheric CO<inf>2</inf> has resulted in climate warming since the end of 21th century due to its greenhouse effect. Global warming coupled with elevated CO<inf>2</inf> concentration could have a drastic consequence for physiological processes of maize (Zea mays L.), a stable plant with C<inf>4</inf> photosynthetic pathway. Understanding photosynthetic processes, transpiration and water use efficiency of maize under different CO<inf>2</inf> concentration and temperature would shed insight into how maize would respond to climate change. Using growing chambers, we measured growth, photosynthesis and water use efficiency of maize grown in six chambers with day/night temperature controlled at 25/19&#8451;to 37/31&#8451; at ambient CO<inf>2</inf> concentration (400 &micro;mol/mol) and elevated CO<inf>2</inf> concentration (800 &micro;mol/mol), respectively. Other factors in the chambers were kept the same, with the relative humidity being 55% - 65%, photosynthetic photon flux density (PPFD) being 1000 &micro;mol/m²&bull;s, and daily 12 h photoperiod for 60 days. In each treatment, we measured the net photosynthetic rate (P<inf>n</inf>), stomatal conductance (G<inf>s</inf>), transpiration rate (T<inf>r</inf>), leaf water use efficiency (WUE), using a portable photosynthesis system (Licor-6400). In addition, we also measured plant biomass, leaf area, total carbon and nitrogen contents, and soluble sugars (glucose, fructose, and sucrose) in the plant. The results showed that the temperature had a dramatic impact on growth of the maize, whereas the biomass and height of the plants grown under the elevated CO<inf>2</inf> were almost the same as those grown under the ambient CO<inf>2</inf>. It was also found that the response of P<inf>n</inf> to temperature was not affected by CO<inf>2</inf> when temperature was 25/19&#8451; and 37/31&#8451;, while the elevated CO<inf>2</inf> increased P<inf>n</inf> by 16.4% (P<0.05) when temperature was risen to 37/31&#8451;, suggesting that CO<inf>2</inf> elevation might have improved the tolerance of maize to thermal stress thereby reducing thermal damage to maize leaves. Warming significantly increased soluble sugars concentrations, especially the concentration of fructose, when temperature was risen from 25/19&#8451; to 31/25&#8451;, but followed by a decline when temperature was further risen to 37/31&#8451;, alluding that thermal stress might have suppressed the photosynthesis leading to a decrease in soluble sugars content of the leaves. At temperature 37/31&#8451;, the elevated CO<inf>2</inf> boosted soluble sugars in the leaves due to the increased photosynthetic rates, while a further temperature rise reduced the water use efficiency (WUE) of the leaves. The elevated CO<inf>2</inf> enhanced WUE by ameliorating the adverse effect of temperature on WUE, but under different mechanisms. When temperature was 25/19&#8451; and 31/25&#8451;, the elevated CO<inf>2</inf> improved WUE due to the reduction in T<inf>r</inf>, while when the temperature was 37/25&#8451;, the elevated CO<inf>2</inf> alleviated the adverse effect of temperature on photosynthesis to improve WUE. The results suggested that climate warming may reduce P<inf>n</inf> and WUE of maize, but the associated elevated atmospheric CO<inf>2</inf> could alleviate the adverse impact of the warming on P<inf>n</inf> thereby improving the WUE. These findings are helpful for adequately assessing the consequence of climate change for growth and water use efficiency of maize and have important implication for ecosystem management in response to climate change.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:39
Main heading:Carbon dioxide
Controlled terms:Atmospheric humidity - Ecology - Efficiency - Fructose - Global warming - Grain (agricultural product) - Greenhouse effect - Photosynthesis - Plants (botany) - Temperature  - Thermal stress - Transpiration
Uncontrolled terms:Different mechanisms - Ecosystem management - Net photosynthetic rate - Photosynthetic pathways - Photosynthetic photon flux densities - Physiological process - Stomatal conductance - Water use efficiency
Classification code:443.1  Atmospheric Properties - 454.3  Ecology and Ecosystems - 461.9  Biology - 641.1  Thermodynamics - 741.1  Light/Optics - 804.1  Organic Compounds - 804.2  Inorganic Compounds - 821.4  Agricultural Products - 913.1  Production Engineering - 931.2  Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Age 1.64e-01yr, Percentage 5.50e+01% to 6.50e+01%, Time 4.32e+04s
DOI:10.11975/j.issn.1002-6819.2020.05.014

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 2>

Accession number:20202108693707
Title:Measurement method and mathematical model for the seeding downforce of planter row unit
Title of translation:&#25773;&#31181;&#21333;&#20307;&#23545;&#22320;&#19979;&#21387;&#21147;&#27979;&#37327;&#26041;&#27861;&#21644;&#25968;&#23398;&#27169;&#22411;
Authors:Gao, Yuanyuan (1, 2); Zhai, Changyuan (2); Yang, Shuo (1, 2); Zhao, Xueguan (2); Wang, Xiu (2, 3); Zhao, Chunjiang (1, 3)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (2) Beijing Research Center of Intelligent Equipment for Agriculture, Beijing; 100097, China; (3) 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:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Appropriate and consistent seeding downforce can reduce the vibration of row units and improve the stability of sowing depth. Studies have shown that the existing real-time measurement methods are not suitable for precise control of downforce due to the poor universality of methods, inadequate stability and low accuracy of output. To solve these problems and promote the development and application of downforce control technology, a universal measurement method was adopted by replacing the pin shaft of the limit block with the axle pin sensor. The mechanical analysis and design selection methods of the axle pin sensor were studied, which could provide a reference for the design of pin sensor with similar structure in the future. Based on the analysis of the motion of a gauge wheel, a relationship model between the seeding downforce and the sowing depth was established, which pointed out that the angle of limit shank was an important factor affecting the accuracy of downforce measurement. Then a sowing depth measurement device based on the angle of limit shank was designed and the corresponding depth measuring model was established to reduce the measurement error of single variable model with different sowing depth settings. Equipped with the sowing depth measurement device and the axle pin sensor, an indoor test platform was built and a modeling experiment with six kinds of sowing depth and seven levels of downforce was conducted. By using the polynomial approximation fitting method with Matlab, the sensor data was analyzed and a bivariate correction downforce measurement model was established with determination coefficient (R²) of 0.991 6 and root mean square error (RMSE) of 28.88 N. To accurately evaluate the predictive performance of the model, a validation test with another three sowing depth settings and six downforce values was designed and carried out. The results showed that the maximum absolute value of prediction error was 44.13 N and the maximum relative prediction error was 3.28% with different sowing depth settings, which indicated that the downforce measurement model had good universality and accuracy. Furthermore, to analyze the frequency composition of dynamic change of seeding downforce caused by collision and impact during seeding operation, a field experiment of two-factor split plot was carried out with tillage mode and speed as experimental factors, and the data was collected by an electronic control unit (ECU) with the sample frequency of 200 Hz. Spectrum analysis of the data by discrete Fourier transform (DFT) showed that the time-domain variation of downforce was sharper at higher planting speed and a larger margin of downforce occurred in no-tillage field, which led to the increase of high-frequency components. Besides that, the main frequency amplitude of downforce vibration decreased with the increase of planting speed, whose maximum value was at 4 km/h, corresponding to 219.1 N and 161.4 N for the no-tillage field and the rotary tillage field respectively. The results of power spectral density (PSD) analysis of downforce signal showed that the main frequency amplitude and peak value of PSD in the no-tillage field were larger than that in the rotary tillage field. Moreover, the vibration frequency was less affected by tillage mode and planting speed, mainly concentrated in 0-1 Hz, which could provide a reference for low-pass filtering of signals in downforce control. The study can lay a foundation for precise control of seeding downforce.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Time domain analysis
Controlled terms:Axles - Control systems - Cultivation - Design for testability - Discrete Fourier transforms - Errors - Frequency domain analysis - Low pass filters - Mean square error - Polynomial approximation  - Power spectral density - Seed - Signal analysis - Spectral density
Uncontrolled terms:Determination coefficients - Development and applications - Electronic control units - High frequency components - Power spectral densities (PSD) - Predictive performance - Real time measurements - Root mean square errors
Classification code:703.2  Electric Filters - 716.1  Information Theory and Signal Processing - 731.1  Control Systems - 821.3  Agricultural Methods - 821.4  Agricultural Products - 921  Mathematics - 922.2  Mathematical Statistics
Numerical data indexing:Force 1.61e+02N, Force 2.19e+02N, Force 2.89e+01N, Force 4.41e+01N, Frequency 0.00e+00Hz to 1.00e+00Hz, Frequency 2.00e+02Hz, Percentage 3.28e+00%, Velocity 1.11e+00m/s
DOI:10.11975/j.issn.1002-6819.2020.05.001

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 3>

Accession number:20202108693800
Title:Unsupervised feature selection and fragmentation optimization of agriculture management zones at a regional scale
Title of translation:&#21306;&#22495;&#23610;&#24230;&#20892;&#19994;&#31649;&#29702;&#20998;&#21306;&#30340;&#26080;&#30417;&#30563;&#29305;&#24449;&#36873;&#25321;&#19982;&#30772;&#30862;&#24230;&#20248;&#21270;&#31639;&#27861;
Authors:Huang, Fen (1, 2); Zhu, Jincheng (1); Zhang, Xiaohu (2); Liu, Tongyu (1); Zhu, Yan (2)
Author affiliation:(1) College of Information Science & Technology, Nanjing Agricultural University, Nanjing; 210095, China; (2) National Engineering and Technology Center for Information Agriculture, Nanjing Agricultural University, Nanjing; 210095, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:192-200
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Dividing farmland into different zones for facilitating management (management zone) at regional scales can help improve agricultural production in reforming agricultural technology implementation in China. Improving detailed prescription of the management zone division can provide guidance to farming and service optimization at regional scale. Appropriately selecting indexes in management zones can reduce the required data and can thus subsequently improve management. Available index selection usually relies on empirical knowledge of experts and/or multivariate statistical analysis. However, expert evaluation method could be bias, while the multivariate statistical analysis method cannot reduce the number of indexes compared to the original index set and thus need to supervise the data. In addition, most existing work on fragmentation of management zones focused on zone-dividing method rather than from index selection by removing indexes that lead to fragmentation. This paper aims to resolve these limitations with a proposed unsupervised filtering index selection method, based on the index correlation clustering (FSCC) using the concept of feature selection. FSCC reduces the original index set to obtain a subset called FSCC set. FSCC applies the correlation matrix of all indexes to cluster the original indexes set. It then selects all cluster centers as a representatives to form a new index subset as the FSCC set. The quantity of the indexes in the FSCC set was reduced, compared to the original index set, and the redundancy of the indices set was descended. To improve practical operability of the management zones, we applied the index optimization algorithm developed based on the consistency and integrity (CIO) to the FSCC set to remove indices which resulted in fragmentation. CIO couples Kappa Coefficient with fragmentation index to generate an optimization strategy for the FSCC sets. CIO screens the indices which lead to the fragmentation while, in the meantime, considering the consistency of the management zone results prior to and after the optimization. We applied the method to winter wheat in China, with factors that affect wheat growth, including meteorology, soil and topography, being divided at four regional scales. We first used the FSCC and the two traditional filter feature selection methods, Variance and Laplacian Score, to select index subsets for the four scales, and compared the resultant management zones produced from them. The CIO was then applied to the four scales produced by the FSCC. The results showed that the FSCC method preserves the diversity of the features in the original index set. It significantly removed the redundant indices and had a better performance in the management zones. The best performance shows that in Rugao 2.5 km Grain, FSCC less than 52.44%, 49.52%, 49.45% both of Variance and Laplacian Score in FPI, MPE, NCE. The CIO improved the management zones effect of the FSCC index set, which reduced the number of indexes and effectively removed the indexes that led to a number of isolated units or patches. Compare to FSCC, except Nantong 10km, CIO has an average decrease in FPI, MPE, NCE of 0.061, 0.078, 0.082. Using the four regional scales, FSCC and CIO presented in this paper were effective in selecting indices and have potential application in management zone division.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:53
Main heading:Feature extraction
Controlled terms:Agricultural robots - Agriculture - Electron emission - Laplace transforms - Multivariant analysis - Topography
Uncontrolled terms:Agricultural productions - Agricultural technologies - Correlation clustering - Expert evaluation method - Feature selection methods - Multivariate statistical analysis - Optimization algorithms - Unsupervised feature selection
Classification code:821  Agricultural Equipment and Methods; Vegetation and Pest Control - 921.3  Mathematical Transformations - 922  Statistical Methods - 951  Materials Science
Numerical data indexing:Percentage 4.95e+01%, Percentage 5.24e+01%, Size 1.00e+04m, Size 2.50e+03m
DOI:10.11975/j.issn.1002-6819.2020.05.022

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 4>

Accession number:20202108693785
Title:Design and test of eject lifting type pot seedling detaching device
Title of translation:&#39030;&#20986;&#25176;&#20030;&#24335;&#38069;&#33495;&#33073;&#30424;&#35013;&#32622;&#35774;&#35745;&#19982;&#35797;&#39564;
Authors:Feng, Shijie (1, 2); Wu, Mingliang (1, 3); Yan, Bo (1); Quan, Wei (1)
Author affiliation:(1) College of Mechanical and Electrical, Hunan Agricultural University, Changsha; 410128, China; (2) College of Horticulture, Xinyang Agriculture and Forestry University, Xinyang; 464000, China; (3) Hunan Provincial Engineering Technology Research Center for Modern Agricultural Equipment, Changsha; 410128, China
Corresponding author:Wu, Mingliang(mlwu@hunau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:50-58
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Aiming at the problems of seedlings injury, seedling pot cracking and high matrix loss rate in the operation process of automatic seedling device, a eject lifting type device for pot seedling detaching from movable tray was designed. The device was mainly composed of seedling tray conveyor, tray positioning mechanism, opening and lifting mechanism and control system. According to the structure of the movable tray, a three-dimensional positioning mechanism composed of half Y shaped positioning bars, guidance positioning wheels and positioning plates was designed to position the tray from longitudinal, transverse and vertical directions, so as to ensure that movable tray could be accurately positioned in operating area. According to the characteristics that the pot hole of movable tray could be opened, an opening and lifting mechanism consisting of short push plate, long push plate and lifting platform was designed. Short push plate and long push plate were sequentially opened by longitudinal side plate and lateral side plate which were used for movable tray positioning so as to separate seedling pot from pot hole. At the same time, after the separation, lifting platform lifted seedling pot which started to slide along the wall of pot hole from bottom and lifted it to the designed height for subsequent operations. The control system of device for seedling detaching from movable tray was designed. PLC controlled the operation of each driving motor according to the outputs signals of the movement sequence of each mechanism, so that each mechanism could coordinate in order to realize the automatic detaching of seedling pot from movable tray. In order to verify the operation effects of the device for seedling detaching from movable tray, bench experiments were carried out. Seedling pot lifting speed, type of the end face of lifting platform and moisture content of matrix of seedling pot were used as experimental factors. The qualified rate of position of seedling pot on the end face of the lifting platform and the loss rate of seedling pot matrix in process of seedling pot detaching from movable tray were taken as the evaluation indexes. Rapeseed seedlings of 35-day-old which were cultured in a 16-hole movable tray were used as the object. An experimental scheme of L<inf>9</inf> (3⁴) orthogonal table was used for the bench experiments to study the influence of various factors on the evaluation indexes. Through the range analysis and variance analysis of experimental data, the influence order of each factor on the evaluation indexes were obtained, which were material type of end face of lifting platform, seedling pot lifting speed and moisture content of matrix of seedling pot. At the same time, the optimal parameter combination of the experimental factors was obtained in the experiments: the lifting speed was 32 mm/s, the material of the end face of lifting platform was rubber, and the moisture content of the matrix was 55%. Verification experiments with optimal parameter combination were carried out and the results showed the qualified rate of positions of seedling pot on the end face of the lifting platform was 100% and the loss rate of seedling pot matrix was 1.56%, which indicated that the device for seedling pot detaching from movable tray met the requirement of actual operations. The study provides important theoretical basis and reference for the design and further study on seeding automatic pick-up and transplanting mechanism.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Plates (structural components)
Controlled terms:Control systems - Moisture - Moisture determination
Uncontrolled terms:Experimental factors - Experimental scheme - Lifting mechanisms - Operation process - Optimal parameter combinations - Three-dimensional positioning - Transplanting mechanisms - Vertical direction
Classification code:408.2  Structural Members and Shapes - 731.1  Control Systems - 944.2  Moisture Measurements
Numerical data indexing:Percentage 1.00e+02%, Percentage 1.56e+00%, Percentage 5.50e+01%, Velocity 3.20e-02m/s
DOI:10.11975/j.issn.1002-6819.2020.05.006

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 5>

Accession number:20202108693693
Title:Model for predicting the temperature of glass greenhouse cover considering dynamic absorptivity
Title of translation:&#32771;&#34385;&#21160;&#24577;&#21560;&#25910;&#29575;&#30340;&#29627;&#29827;&#28201;&#23460;&#35206;&#30422;&#23618;&#28201;&#24230;&#39044;&#27979;&#27169;&#22411;
Authors:Zhang, Guanshan (1, 2); Li, Tianhua (1, 2); Hou, Jialin (1, 2)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Shandong Agricultural University, Tai'an; 271018, China; (2) Shandong Provincial Engineering Laboratory of Agricultural Equipment Intelligence, Tai'an; 271018, China
Corresponding author:Hou, Jialin(jlhou@sdau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:201-211
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The cover temperature has an important effect on the thermal behavior of the greenhouse. This research developed and validated a prediction model of the cover temperature considering dynamic cover absorptivity. The absorptivity of the cover changes with the time of day and depending on many parameters such as the refractive coefficient, extinction coefficient, and thickness of the cover. The dynamic absorptivity of the cover was used to improve the model's accuracy. The absorptivity of the cover was divided into the absorptivity of beam radiation, diffuse radiation, and ground-reflected radiation. This mathematical model also considered the thermodynamic exchanges between the cover and other components of the greenhouse including the convection, shortwave and longwave radiation. A computer program adopting the MATLAB standard solver ode45 was written to find a solution to the energy equations employing a fourth-order Runge-Kutta method. The input parameters of the model were the measurement of the meteorological environment and thermo-physical characteristics of the greenhouse components including those of the soil and inside air. The thermophysical characteristics of the greenhouse were determined by the material properties of the glass greenhouse and the construction scheme, which were not affected by the geographic location of the glass greenhouse. Initial input values for these equations were the measured temperatures of cover, soil, and air at t=0. Employing the computer program model built-in MATLAB, trends of temperature in the greenhouse were acquired by solving the unsteady-state energy balance equation for the structural components of the greenhouse and estimating heat absorbed by various surfaces. The model was validated utilizing measured data of three non-continuous periods of 10 days in three seasons in the north of China in Shandong province (36&deg;08'N, 116&deg;95'E). To predict the model accuracy, varying statistical indicators, including the root-mean-square error (RMSE), and the square of the correlation coefficient (R²) was determined from data series. The model's accuracy was verified by comparing the calculated temperatures with experimental measurements for the glass greenhouse. The best results were obtained with RMSE=1.26 &#8451; and R²=0.98 for the cover temperature. The worst results were obtained with RMSE=2.05 &#8451; and R²=0.92 for the cover temperature. Statistical analysis confirmed that the developed model was effective in forecasting the microclimate of the greenhouse. Finally, we compared the accuracy of this model with related research abroad. With the comparison, we concluded that the accuracy of the model was higher than that of the related research abroad. Because this research considered the dynamic absorptivity of the greenhouse cover creatively. Besides, this study had an energy analysis of solar radiation flux absorbed by the cover with the experimental greenhouse as a study case. The results indicated that the south wall absorbed less solar radiation in the summer period, while other walls and roofs absorbed more solar radiation in the summer period. The solar radiation absorbed by the east wall and the west wall was almost equal. The north wall absorbed the least solar radiation compared with other walls and roofs. It is clear that the quantification of solar radiation as demonstrated here is of great interest to the growers and is essential for the model's accuracy and greenhouse management.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Greenhouse effect
Controlled terms:Equations of state - Forecasting - Glass - Greenhouses - MATLAB - Mean square error - Predictive analytics - Roofs - Runge Kutta methods - Solar radiation  - Temperature - Walls (structural partitions)
Uncontrolled terms:Correlation coefficient - Extinction coefficients - Fourth order Runge-Kutta methods - Physical characteristics - Root mean square errors - Solar-radiation fluxes - Statistical indicators - Thermophysical characteristics
Classification code:408.2  Structural Members and Shapes - 451  Air Pollution - 641.1  Thermodynamics - 657.1  Solar Energy and Phenomena - 812.3  Glass - 821.6  Farm Buildings and Other Structures - 921  Mathematics - 921.6  Numerical Methods - 922.2  Mathematical Statistics
Numerical data indexing:Age 2.74e-02yr
DOI:10.11975/j.issn.1002-6819.2020.05.023

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 6>

Accession number:20202108693503
Title:Compaction effects of wheeled vehicles and tracked on farmland soil
Title of translation:&#36718;&#24335;&#21644;&#23653;&#24102;&#24335;&#36710;&#36742;&#34892;&#36208;&#23545;&#20892;&#30000;&#22303;&#22756;&#30340;&#21387;&#23454;&#20316;&#29992;&#20998;&#26512;
Authors:Ding, Zhao (1); Li, Yaoming (1); Tang, Zhong (1)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang; 212013, China
Corresponding author:Li, Yaoming(ymli@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:10-18
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil compaction induced by vehicle traffic has aroused more concerns due to its negative impacts on soil functions and ecosystems. Replacing tires by tracks is considered as a technical method to mitigate the soil compaction, which increases the vehicle's contact area and decreases the mean ground pressure. However, the interactions between the track and the soil are complex, the stress distribution at the interface between the track and the soil is uneven, which may reduce the effectiveness of the track in decreasing soil stress. Thus, to determine the ability of track to reduce the soil compaction compared with tire is importance. The objective of this study is to investigate the impact of undercarriages (tire vs. track) on the magnitude of soil stress and soil functions (i.e. pre-compression stress, air permeability, dry bulk density), as well as the impact of vehicle velocity on the magnitude of soil stress. The test was conducted on the sandy loam soil. Three repeated measurements were carried out on tracked harvester and tractor with similar axle load. To measure soil stress, the load transducers were embedded in the centerline of the tire and track at a depth of 0.15 and 0.35 m respectively. After vehicles pass, soil samples are collected at the depth of 0.15 and 0.35 m in the test area. Soil pre-compression stress, air permeability and dry bulk density were measured in the lab. The soil stress in the depth range of 0.1-0.7 m was calculated by using the soil compaction model. The results show that compared with tires, the vertical and horizontal soil stresses are reduced under the track compaction. However, the reduction of the vertical stress was greater than that of the horizontal stress. Under the effect of tyre compaction, the average vertical stress at the depth of 0.15 and 0.35 m is 2.2 and 2.0 times of track compaction respectively, whereas the average horizontal stress of tyre compaction was only approximate 1.2 and 1.1 times larger than that of the track respectively. Interestingly, no difference in vertical and horizontal stress was found between the track and the tire compaction at the depth of 0.7 and 0.4 m respectively. It indicates that the track is more effective in reducing the soil compaction for the topsoil than for the subsoil. The vertical and horizontal compaction stresses of tire and tracked vehicle decrease with the increase of vehicle speed, but the speed of stress reduction under the track compaction is faster than that of tire. The measured air permeability of track compaction is obviously larger than that of tire, whereas the measured dry density and pre-compression stress displayed no significant difference between the tire and track compation. In other words, the ability of the track to reduce soil compaction is weakened due to the uneven stress distribution and the longer compaction time. Though the calculated soil stress is generally in line with the measurement results, the measured vertical stress is lower than the calculated value for the tire compaction but higher for the track compaction, the measured horizontal stress are lower than the calculated values for both the tire and the track compaction. The accurate prediction of the distribution of stress on tire/track surface and the reasonable selection of concentration factor are the key to model calculations. Future research may focus on the impact of support roller configuration and diameter on the distribution of soil stress of track compaction. The research results are helpful to improve the uniformity of soil stress distribution under the track compaction, so as to reduce soil compaction.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:48
Main heading:Soil surveys
Controlled terms:Air - Air permeability - Compaction - Soil mechanics - Soils - Stress concentration - Tires - Tracked vehicles
Uncontrolled terms:Accurate prediction - Compaction stress - Concentration factors - Dry bulk densities - Mean ground pressures - Model calculations - Repeated measurements - Soil compaction models
Classification code:483.1  Soils and Soil Mechanics - 663  Buses, Tractors and Trucks - 804  Chemical Products Generally - 818.5  Rubber Products - 931.2  Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Size 1.00e-01m to 7.00e-01m, Size 1.50e-01m, Size 3.50e-01m, Size 4.00e-01m, Size 7.00e-01m
DOI:10.11975/j.issn.1002-6819.2020.05.002

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 7>

Accession number:20202108694011
Title:Evaluation of cultivated land productivity based on potential attenuation model in the dryland farming regions of Northeast and North China Plain
Title of translation:&#22522;&#20110;&#28508;&#21147;&#34928;&#20943;&#27169;&#22411;&#30340;&#19996;&#21271;-&#21326;&#21271;&#24179;&#21407;&#26097;&#20316;&#21306;&#32789;&#22320;&#29983;&#20135;&#21147;&#35780;&#20215;
Authors:Wan, Wei (1, 2); Deng, Jing (1, 2); Wang, Jiaying (1, 2); Liu, Zhong (1, 2); Han, Yiwen (1, 2); Zheng, Mandi (1, 2)
Author affiliation:(1) College of Land Science and Technology, China Agricultural University, Beijing; 100193, China; (2) Key Laboratory of Arable Land Conservation in North China, Ministry of Agriculture and Rural Affairs, Beijing; 100193, China
Corresponding author:Liu, Zhong(lzh@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:270-280
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the cultivatable lands dwindling and concern over food security increasing in China, understanding the productivity of its croplands has become increasingly significant. Taking the drylands in the Northeast and North China Plains as examples, we estimated the production potential of maize based on spatial variation of light and temperature in these regions. Using data obtained from the national statistics bureau in a combination with land, precipitation, soil, social and economic data from 1995 to 2015, we calculated spatiotemporal variation of productivity of the cultivable lands and its determinants using the potential attenuation model. The results showed that: 1) The light-temperature-water production, light-temperature-water-soil production, light-temperature-water-soil-socio-economic production of the drylands in the Northeast China Plain were all higher than those in the North China Plain. Spatially, the productivity of the drylands in both plains increased from the north to the south. 2) Correction analysis between the determinants revealed that investments in social and economic development was extremely important for protecting production of the available cultivable lands, especially the drylands in the North China Plain that has been in degradation. 3) In both plains, the difference in water yield gap was lower in the south than in the north, and lower in the east than in the west, while the difference in soil yield gap was higher in the south than in the north; the difference in socio-economic yield gap was higher in the north than in the south; these spatial variations were closely related to the zonal geography in China, including soil quality, natural environment and other social and economic factors in the Northeast Plain. 4) The yield gaps caused by different factors in both plains were ranked in yield gap affected by socio-economic factor > yield gap affected by soil factor > yield gap affected by water factor. The difference in social and economic output was small in the drylands in the north China Plain, and the difference in soil yield was small in the drylands in the Northeast China Plain. These further proved that investment in social and economic development was most important for maintaining productivity of the cultivatable dryland in the North China Plain while the inherent natural environment was most important for ensuring productivity of the drylands in the Northeast China Plain. The potential attenuation model is an effective to estimate productivity of large-scale farmland, and its results provide guidance for sustaining high and stable crop yield while in the meanwhile reducing land degradation in different agricultural regions.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:39
Main heading:Economic and social effects
Controlled terms:Agricultural robots - Agriculture - Economics - Food supply - Landforms - Productivity - Soils
Uncontrolled terms:Attenuation model - National statistics - Natural environments - North China Plain - Social and economic development - Socio-economic factor - Spatial variations - Spatio-temporal variation
Classification code:481.1  Geology - 483.1  Soils and Soil Mechanics - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 822.3  Food Products - 971  Social Sciences
DOI:10.11975/j.issn.1002-6819.2020.05.032

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 8>

Accession number:20202108693537
Title:Effects of long-term green manure and reducing nitrogen applications on rice yield and soil nutrient content
Title of translation:&#38271;&#26399;&#32511;&#32933;&#19982;&#27694;&#32933;&#20943;&#37327;&#37197;&#26045;&#23545;&#27700;&#31291;&#20135;&#37327;&#21644;&#22303;&#22756;&#20859;&#20998;&#21547;&#37327;&#30340;&#24433;&#21709;
Authors:Zhang, Lu (1, 2); Huang, Jing (1, 2); Gao, Jusheng (1, 2); Cao, Weidong (1); Gao, Peng (3); Yang, Zhichang (2)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences/National Engineering Laboratory for Improving Quality of Arable Land, Beijing; 100081, China; (2) Hengyang Red Soil Experimental Station, Chinese Academy of Agricultural Sciences/National Observation and Research Station of Farmland Ecosystem in Qiyang, Qiyang; 426182, China; (3) Hunan Institute of Agricultural Environment and Ecology, Hunan Academy of Agricultural Sciences, Changsha; 410125, China
Corresponding author:Gao, Jusheng(gaojusheng@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:106-112
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Green manure is a natural clean organic source of fertilizer. Chinese milk vetch is the most popular winter green manure crop in rice-growing regions of China. In this study, a long-term field experiment was conducted at an experimental station managed by National Observation and Research Station of Farmland Ecosystem in Qiyang, China to explore suitable application amount of nitrogen fertilizer when returning green manure(Chinese milk vetch, Astragalus sinicus L.) to the field in the double-season rice area of southern Hunan. The double cropping rice experiment began from the winter of 2008. It lasted 9 years. A total of six treatments with different fertilization practices were included: 1) CK, without fertilization; 2) MV, Chinese milk vetch only; 3) FFP100%, conventional application rate of chemical nitrogen fertilizer; 4) MV+FFP100%, Chinese milk vetch combined with 100% conventional application rate of chemical nitrogen fertilizer; 5) MV+FFP80%, Chinese milk vetch combined with 80% conventional application rate of chemical nitrogen fertilizer; 6) MV+FFP60%, Chinese milk vetch combined with 60% conventional application rate of chemical nitrogen fertilizer. The yield of rice and soil nutrient content were measured. The nitrogen agronomic efficiency and nitrogen partial factor productivity, coefficient of variation and sustainable index of yield were calculated. The results showed that the treatments of green manure combined with different chemical nitrogen fertilizer application rate kept and even increased annual rice yield. The treatments of MV combined with reducing nitrogen application also increased the nitrogen agronomic efficiency and nitrogen partial factor productivity. Compared to FFP100%, the treatments MV+FFP100%, MV+FFP80% and MV+FFP60% resulted in the increase of long-term average of nitrogen agronomic efficiency by 34.63%, 64.91% and 115.26% in early rice, respectively, and by 29.69%, 56.23% and 72.09% in late rice, respectively(P<0.05). Compared to that of FFP100%, the long-term averages of nitrogen partial factor productivity of MV+FFP100%, MV+FFP80%, MV+FFP60% increased by 8.73%, 35.06% and 78.92% in early rice, respectively, and 7.51%, 32.90% and 68.06% in late rice, respectively. Among all the treatments, regardless of early and late rice, the treatment of MV+FFP60% had the smallest coefficient of variation of yield and the highest sustainable index. Soil organic matter, total nitrogen, total phosphorus and total potassium were not significantly different among the treatments of FFP100%, MV, MV+FFP100%, MV+FFP80%, MV+FFP60% (P>0.05). But, they were higher than the initial values in 2018. The treatment of Chinese milk vetch combined with 60% conventional application rate of chemical nitrogen fertilizer could achieve high and stable yield, and improve the nitrogen use efficiency and slowly improve soil fertility. Therefore, Chinese milk vetch combined with 60% conventional application rate of chemical nitrogen fertilizer was suggested as the best fertilization mode for double-cropping rice planting area in southern Hunan. In this case, the chemical fertilizer application rate could be decreased by 40% compared to the conventional fertilizer practice.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Nitrogen fertilizers
Controlled terms:Agronomy - Dairies - Ecosystems - Efficiency - Manures - Nutrients - Productivity - Soils
Uncontrolled terms:Chemical fertilizers - Coefficient of variation - Experimental stations - Fertilizer applications - Long-term field experiments - Nitrogen-use efficiency - Partial factor productivity - Soil organic matters
Classification code:454.3  Ecology and Ecosystems - 483.1  Soils and Soil Mechanics - 804  Chemical Products Generally - 821.3  Agricultural Methods - 821.5  Agricultural Wastes - 822.1  Food Products Plants and Equipment - 913.1  Production Engineering
Numerical data indexing:Age 9.00e+00yr, Percentage 1.00e+02%, Percentage 1.15e+02%, Percentage 2.97e+01%, Percentage 3.29e+01%, Percentage 3.46e+01%, Percentage 3.51e+01%, Percentage 4.00e+01%, Percentage 5.62e+01%, Percentage 6.00e+01%, Percentage 6.49e+01%, Percentage 6.81e+01%, Percentage 7.21e+01%, Percentage 7.51e+00%, Percentage 7.89e+01%, Percentage 8.00e+01%, Percentage 8.73e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.012

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 9>

Accession number:20202108693589
Title:Effects of acid-acclimated inoculum on solid-state anaerobic digestion of spent mushroom substrate
Title of translation:&#25509;&#31181;&#29289;&#32784;&#37240;&#39535;&#21270;&#23545;&#33740;&#31968;&#21388;&#27687;&#24178;&#21457;&#37237;&#20135;&#27668;&#30340;&#24433;&#21709;
Authors:Zhu, Jiying (1); Zhong, Hui (1); Lu, Yu (1); Zhang, Qi (1)
Author affiliation:(1) School of Agricultural Engineering and Food Science, Shandong University of Technology, Zibo; 255000, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:249-254
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Solid-state anaerobic digestion (SS-AD) generally operates at solid content between 20%-40%. Due to the low water content, mass transfer in the digestion material is slow and the intermediate acids are apt to accumulate locally. Excessive acid accumulation might inhibit the activity of methanogens, reduce bigas yield, and even result in failure of the SS-AD process. Acetic acid is the most important intermediate in anaerobic digestion, and its concentration directly affects the activity of methanogens. Spent mushroom substrate (SMS) is a feasible feedstock for anaerobic digestion, because it has high organic content and the fiber and lignin have been greatly degraded during mushroom growth. However, using spent mushroom substrate as feedstock for SS-AD is easy to result in acid inhibition due to the rapid hydrolysis and acidification of the organic matters. In order to avoid acid inhibition and improve the stability of SS-AD process, the inoculum was acclimated by gradually increasing the concentration of acetic acid in this study. The acclimation process was divided into four stages at the pH value of 7.2, 6.7, 6.2 and 6.0, respectively. During acclimation stage, the pH value of the inoculum was adapt to the set value with 6 mol/L acetic acid solution and the biogas production, methane content, additive ammout of acetic acid and conversion of actic acid were measured every day. The activities of dehydrogenase, CMCase and Co F<inf>420</inf> were measured at the last day of each acclimation stage. The acclimation lasted for 40 days and a acid-acclimated inoculum that can prouduce biogas quickly under the condition of acetic acid concentration of 10 200 mg/kg and pH value 6.0 was obtained. Compared to the original inoculum, the diversity of methanogens in the acid-acclimated inoculum decreased and the abundance of acetic acid diauxotrophic Methanosarcina was obviously enriched. The activity of dehydrogenase increased 101.5% in the first acclimation stage (pH value 7.2) and then kept decreasing during the next 3 stages. The activity of dehydrogenase reflects the metabolic capacity of all the microorganisms in the digestion system. With the decrease of pH value during the acclimation, the activity of some microorganisms was inhibited. Coenzyme F<inf>420</inf> is present in various methanogens. It often be used to reflect the methane production activity of sludge. The activty of coenzyme F<inf>420</inf> also reached the highest in the first acclimation stage because the pH is optimum for most methanogenes. Although the abundance of the acetic acid diauxotrophic Methanosarcina was significantly enriched in the final acid-acclimated inoculum, the diversity of the archaea communities was reduced due to the low pH value. The activity of cellulase in the acclimation process reached the highest in the third stage (pH value 6.7). To investigate the effects of acid-acclimated inoculum, SS-AD experiments of SMS were carried out by adding different proportion of acid-acclimated inoculum. The results showed that adding acid-acclimated inoculum could avoid acid inhibition and accelerate the start-up of SS-AD. The methane yield increased 56.1% when acid-tolerant inoculum accounted to 75%. The results can provide some theoretical guidance for effectively solving acid inhibition in SS-AD process.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Anaerobic digestion
Controlled terms:Acetic acid - Biogas - Coenzymes - Feedstocks - Mass transfer - Methane - Methanogens - pH
Uncontrolled terms:Acetic acid concentration - Acid accumulations - Concentration of acetic acid - Different proportions - Hydrolysis and acidifications - Metabolic capacities - Solid-state anaerobic digestions - Spent mushroom substrates
Classification code:461.9  Biology - 522  Gas Fuels - 641.3  Mass Transfer - 801.1  Chemistry, General - 804.1  Organic Compounds
Numerical data indexing:Age 1.10e-01yr, Molar_Concentration 6.00e+03mol/m3, Percentage 1.02e+02%, Percentage 2.00e+01% to 4.00e+01%, Percentage 5.61e+01%, Percentage 7.50e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.029

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 10>

Accession number:20202108693668
Title:Construction of staged hot-air drying dynamic model for American ginseng
Title of translation:&#35199;&#27915;&#21442;&#20998;&#27573;&#24335;&#28909;&#39118;&#24178;&#29157;&#21160;&#21147;&#23398;&#27169;&#22411;&#26500;&#24314;
Authors:Wu, Xiaohua (1); Ma, Yuanbo (1); Ning, Xudan (1); Wang, Peng (1); Zhang, Zhentao (2)
Author affiliation:(1) Beijing Key Laboratory of Pipeline Critical Technology and Equipment for Deepwater Oil & Gas Development, Beijing Institute of Petrochemical Technology, Beijing; 102617, China; (2) Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing; 100080, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:318-324
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:American ginseng is a perennial herb of the genus ginseng. Its rhizome can be used as medicine, and it is a traditional and precious Chinese medicinal material. In addition, it has also been favored as a health product. Research indicates that the rhizomes, leaves, flowers and fruits of American ginseng are rich in biologically active constituents, including ginsenoside, polysaccharide, various amino acids, vitamins, volatile oil, minerals and other chemical components, which are conducive to anti-aging and enhance human immunity. Hot air drying is a key step for the processing of American ginseng, which is divided into two categories: constant condition drying and stages-varied drying. Among the two methods, the stages-varied drying process is widely used in drying production, which contains multiple drying stages and different drying conditions at each stage. The drying characteristics of the materials are fully considered in the condition setting of stages-varied drying, which is conducive to improve the drying quality and save energy in the drying process. The drying kinetic model can reveal the change rule of moisture ratio of materials and provide scientific basis for the development of drying processes. Under the condition of constant temperature drying, the accurate moisture content of materials can be obtained by directly considering the drying parameters in the existing dynamic model of hot air drying. However, since the drying conditions are different at each stage of stages-varied drying, the drying constants are different at each stage in the drying model. In traditional studies, the moisture ratio at each drying stage cannot be accurately obtained if the drying time of stages-varied drying is directly taken into account in the drying kinetics model. To solve this problem, a calculation method of drying kinetics model for the stage-varied drying was proposed, which can accurately analyze the variation of moisture ratio during the stages-varied drying process. In order to establish the method, the drying experiment of American ginseng was carried out and the experimental results were fitted. The results showed that the Modified Page model was the best drying kinetic model for the hot-air drying of American ginseng. The partial regression coefficient was obtained by linear regression analysis of drying conditions and drying constants. Based on the partial regression results, the stage-varied drying process of American ginseng was analyzed and the drying kinetics model for each stage of American ginseng stages-varied drying was obtained. By using the proposed calculation method, the change of moisture ratio in the stages-varied drying process of American ginseng was calculated and compared with the results of the American ginseng stages-varied hot-air drying experiment. It was found that the maximum relative error between the calculation results and the experimental results was 7.44%, the average relative error was only 1.78%. The results indicate that the proposed stages-varied drying kinetic model calculation method can be used to analyze the change of the moisture ratio in the drying process of agricultural products.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Drying
Controlled terms:Agricultural products - Agricultural robots - Dynamic models - Kinetic parameters - Kinetic theory - Moisture - Plants (botany) - Regression analysis - Solar dryers - Volatile organic compounds
Uncontrolled terms:Active constituents - Average relative error - Calculation results - Constant conditions - Constant temperature drying - Drying characteristics - Maximum relative errors - Partial regression coefficients
Classification code:657.1  Solar Energy and Phenomena - 804.1  Organic Compounds - 821.4  Agricultural Products - 921  Mathematics - 922.2  Mathematical Statistics - 931  Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 1.78e+00%, Percentage 7.44e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.037

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 11>

Accession number:20202108693667
Title:Spatial-temporal variation characteristics and attribution analysis of potential evapotranspiration in Beijing-Tianjin-Hebei region
Title of translation:&#20140;&#27941;&#20864;&#22320;&#21306;&#28508;&#22312;&#33976;&#25955;&#37327;&#26102;&#31354;&#28436;&#21464;&#29305;&#24449;&#21450;&#24402;&#22240;&#20998;&#26512;
Authors:Bi, Yanjie (1, 2); Zhao, Jing (1, 2); Zhao, Yong (2); Xiao, Weihua (2); Meng, Fanjin (1)
Author affiliation:(1) North China University of Water Resources and Electric Power, College of Water Resources, Zhengzhou; 450046, China; (2) 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:Zhao, Yong(zhaoyong@iwhr.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:130-140
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:This paper aims to investigate the spatial and temporal variation characteristics of the potential evapotranspiration (ET<inf>0</inf>) and its response to climate change using the collected data from the daily weather observation of 23 meteorological stations in the Beijing-Tianjin-Hebei region for 57 years from 1960-2016. The specific parameters of dataset included the daily average air temperature, the maximum and minimum air temperature, relative humidity, wind speed and sunshine hours. We chose the Penman-Monteith formula to calculate the daily ET<inf>0</inf> at each site, and then analyzed the spatial and temporal variation characteristics of the calculated ET<inf>0</inf>. A sensitivity coefficient was used to quantitatively study the sensitivity of ET<inf>0</inf> to various meteorological elements and its spatial and temporal distribution. The contribution rate was set to evaluate the influence of meteorological elements changes on the variation of ET<inf>0</inf> during the calculation. The results show that: 1) The spatial distribution of ET<inf>0</inf> shows a decreasing trend from south to north across the Beijing-Tianjin-Hebei region, except a high ET<inf>0</inf> in the central region, such as Tanggu, Huangye and Baoding stations. There was a linear decline rate of -0.92mm /a. e in the whole distribution of ET<inf>0</inf>. The spatial distribution of ET<inf>0</inf> MK (Penman-Monteith) decreased from the northwest to southeast. In temporal characteristics, spring has the most obvious decrease, followed by autumn, summer, and winter. 2) The sensitivity coefficient of ET<inf>0</inf> to the average air temperature, sunshine hours, relative humidity and wind speed are 0.26, 0.28, 0.31 and -044, respectively, indicating the most sensitive to the changes of relative humidity in the Beijing-Tianjin-Hebei region, followed by the wind speed and sunshine hours. The sensitivity coefficient of ET<inf>0</inf> to meteorological elements presents in a fluctuating trend from1960-2016, the sensitivity coefficient of ET<inf>0</inf> to the wind speed and relative humidity in a downward trend, while the sensitivity coefficient of ET<inf>0</inf> to average temperature and sunshine hours in an upward trend. The spatial distribution of the sensitivity coefficient from northwest to southeast: the wind speed and average temperature gradually increased, while the sunshine hours and relative humidity gradually decreased. The spatial distribution characteristics of the sensitivity coefficient of ET<inf>0</inf> to relative humidity and average temperature were the opposite situation, where the high sensitivity zone of average temperature belongs to the low sensitive zone of relative humidity. The opposite phenomenon also occurred in the spatial distribution characteristics of the sensitivity coefficient of ET<inf>0</inf> to sunshine hours and wind speed sensitivity, i.e., the high sensitivity zone of sunshine hours belongs to the low sensitive zone of wind speed. 3) The contribution rate of meteorological elements to ET<inf>0</inf> depends on the sensitivity coefficient and the relative change of meteorological elements. ET<inf>0</inf> has the most sensitivity to the changes of relative humidity, but the change rate of the relative humidity was small. ET<inf>0</inf> has the lower sensitive to the changes of wind speed, but the change rate of the wind speed was large, resulting the most contribution to ET<inf>0</inf> in the whole region was the wind speed. However, the stations number of the wind speed as the dominant factor decreased with the measure time, whereas the stations number of the average temperature as the dominant factor increased with the measure time, especially in the period of 2010-2014 to 2010s, 12 stations with the average temperature as the dominant factor. The stations number of the sunshine hours as the dominant factor also increased with the measured time. It infers that the average temperature and sunshine hours have much significant influences on ET<inf>0</inf> in recent years. From 2013 to 2016, the correlation coefficients of the winter average air temperature, sunshine hours, relative humidity, wind speed and PM<inf>2.5</inf> concentration were -0.44, -0.53, 0.42 and -0.35, respectively, while the correlation coefficients of ET<inf>0</inf> and PM<inf>2.5</inf> concentration were -0.37. Therefore, it is possible that the haze, especially winter haze, has a certain impact on meteorological elements, and thereby on ET<inf>0</inf> in the Beijing-Tianjin-Hebei region.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:42
Main heading:Wind
Controlled terms:Atmospheric temperature - Climate change - Evapotranspiration - Spatial distribution - Speed
Uncontrolled terms:Average air temperature - Beijing-tianjin-hebei regions - Correlation coefficient - Distribution characteristics - Potential evapotranspiration - Spatial and temporal distribution - Spatial and temporal variation - Temporal characteristics
Classification code:443.1  Atmospheric Properties - 921  Mathematics
Numerical data indexing:Age 5.70e+01yr
DOI:10.11975/j.issn.1002-6819.2020.05.015

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 12>

Accession number:20202108693482
Title:Simulation and optimization of maize growth and nitrogen utilization under degradation film mulching in arid areas of North China
Title of translation:&#21271;&#26041;&#24178;&#26097;&#21306;&#38477;&#35299;&#33180;&#35206;&#30422;&#20892;&#30000;&#29577;&#31859;&#29983;&#38271;&#21644;&#27694;&#32032;&#21033;&#29992;&#27169;&#25311;&#21450;&#20248;&#21270;
Authors:Li, Xianyue (1); Leng, Xu (1); Zhang, Jingjun (1); Guo, Yu (1); Ding, Zongjiang (1); Hu, Xiaodong (1); Zhu, Kunlun (2)
Author affiliation:(1) College of Water Resources and Civil Engineering, Inner Mongolia Agricultural University, Hohhot; 010018, China; (2) Shandong Eco-Benign Plastics Technology Co., Ltd, Ji'nan; 250110, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:113-121
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is great meaningful to optimize the fertilization system under degradable film mulching for alleviating environmental pollution. In order to capture the effects of degradable film mulching on crop growth and nitrogen fertilizer utilization under in arid area, a two-year experiment (2016-2017) was carried out at the Muleitan water-saving experimental station in Hetao Irrigation District, Inner Mongolia of China. Four nitrogen application levels were set under degradable film mulching: 0 (BN0), 216 (BN1: 160 for topdressing), 276 (BN2: 220 for topdressing) and 336 (BN3: 280 for topdressing) kg/ha, and high nitrogen with plastic film mulching (PN3) and high nitrogen with no mulching (NN3) treatment as a control. The effects of different types of film mulching and different nitrogen application rates on maize growth, nitrogen uptake and utilization efficiency were studied, and the DNDC (denitrification-decomposition) models for different types of film mulching were calibrated and verified, and fertilizer pattern was optimized under degradable film mulching based on the linear and platform model. The results showed that simulated data of the DNDC model on the nitrogen uptake, dry matter accumulation and yield of crops are in good agreement with the measured results, E<inf>F</inf> and R² were all greater than 0.93, R<inf>MSE</inf> was 0.10-0.16, 1181.52-1236.68 and 723.94-761.3 kg/ha, N<inf>RMSE</inf> 7.85%-13.34%, 9.18%-9.73% and 7.52%-8.28%, respectively. There were no significant differences for maize growth between degradable film mulching and plastic film mulching during maize filling stage, the dry matter accumulation for degradable film mulching treatment decreased by 2.41% (P>0.05) compared with the plastic film mulching treatment, and increased by 9.65% (P<0.05) compared with no film mulching treatment. In maize harvest period, the difference of maize growth between plastic film mulching and degradable film mulching increased butdid not reach significant level, only 3.07% (P>0.05), and increased by 9.69% (P<0.05) compared with no film mulching treatment. There were no significant differences in nitrogen uptake, yield, nitrogen use efficiency and daily nitrogen uptake efficiency between the degradable film mulching and plastic film mulching, only decreased by 1.09%, 3.97%, 3.08% and 2.22% (P>0.05), but increased significantly by 7.04%, 13.67%, 12.90% and 8.90% compared with no mulching treatment (P<0.05), respectively. The growth rate of dry matter accumulation was decreased by 1.06%, daily nitrogen uptake, accumulation nitrogen uptake and yield only increased by 0.35%, 0.78 and 0.34% with the increase of nitrogen application rate for BN3 compared with BN2, respectively (P>0.05), while increased by 6.41%, 8.38%, 23.58%, and 35.37% (P<0.05) compared with BN1, so the BN2 treatment with the topdressing nitrogen content of 220 kg/ha showed the best growth and nitrogen utilization. Additionally, the optimal nitrogen rate was 252.94 kg/ha that was obtained by different scenario simulation of DNDC model and optimization of linear and platform model under the degradable film mulching, and there was high nitrogen utilization efficiency, and the yield-increasing effect would not appear if nitrogen fertilizer was continued to increase. So, there was similar effects of degradable film mulching on maize growth and nitrogen utilization compared with plastic film mulching, and the optimal nitrogen application was 252.94 kg/ha, and the maize yield could reach 11 357.37 kg/ha under degradable film mulching in arid area.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:37
Main heading:Growth rate
Controlled terms:Arid regions - Crops - Efficiency - Film growth - Nitrogen fertilizers - Plastic films - Water conservation
Uncontrolled terms:Dry matter accumulation - Environmental pollutions - Hetao irrigation districts - Nitrogen application rates - Nitrogen uptake efficiency - Nitrogen-use efficiency - Simulation and optimization - Utilization efficiency
Classification code:444  Water Resources - 804  Chemical Products Generally - 817.1  Polymer Products - 821.4  Agricultural Products - 913.1  Production Engineering
Numerical data indexing:Percentage 1.06e+00%, Percentage 1.09e+00%, Percentage 1.29e+01%, Percentage 1.37e+01%, Percentage 2.36e+01%, Percentage 3.08e+00%, Percentage 3.40e-01%, Percentage 3.50e-01%, Percentage 3.97e+00%, Percentage 6.41e+00%, Percentage 7.04e+00%, Percentage 7.52e+00% to 8.28e+00%, Percentage 7.80e-01%, Percentage 7.85e+00% to 1.33e+01%, Percentage 8.38e+00%, Percentage 8.90e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.013

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 13>

Accession number:20202108693526
Title:Cooling performance for tomato root zone with intelligent ecological planting matrix temperature control system driven by photovoltaic in greenhouse
Title of translation:&#20809;&#20239;&#39537;&#21160;&#22522;&#36136;&#25511;&#28201;&#31995;&#32479;&#23545;&#28201;&#23460;&#30058;&#33540;&#26681;&#21306;&#30340;&#38477;&#28201;&#25928;&#26524;
Authors:Zhang, Yong (1); Ni, Xinyu (1); Zhang, Kexin (1); Xu, Yingjie (1)
Author affiliation:(1) College of Horticulture, Northwest A&F University, Key Laboratory of Protected Horticultural Engineering in Northwest of Ministry of Agriculture and Rural Affairs, Yangling; 712100, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:212-219
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Short-term or continuous high-temperature conditions usually occur during summer greenhouse production. However, the existing cooling measures either fail to achieve effective cooling effects or consume excessive energy. In order to better realize the annual output of the greenhouse, this study used an ecological intelligent planting matrix temperature control system to cool more efficiently in the summer. The system combined control strategies with ecological intelligence to study the safe production of tomato under high temperature conditions. It was driven by photovoltaics, and the excess power was stored in the battery to maintain the system's operation under adverse weather. The system controlled the temperature of the plant root zone not over 33&#8451;during the day and around 22&#8451;at night. When the system needed to cool down, the DC water pump in the water tank was turned on to drive the water to cool the root zone of the plant through the pipes in the thermal planting groove of the experimental group, and at the same time, the heat exchange with the phase change material was realized by the heat exchanger in the water tank. The matrix temperature at different depths of the substrate in experimental group and control group was compared to evaluate cooling performance of the system. The results showed that it was necessary to cool down twice to reach the appropriate temperature, and it took one hour each time on sunny day in the summer. It took only one time to cool down on cloudy or rainy day. Compared with the control group under the experimental conditions, the average matrix temperatures of experimental group were reduced by 8.65, 11.38, 11.47&#8451; respectively on sunny (2018-07-18), cloudy (2018-06-30) and rainy (2018-07-01) days. The data of the average temperature of the three weathers were calculated by taking the data of sunny, cloudy and rainy days for three consecutive days. The average maximum temperatures at the D8 of the experimental group were 31.26, 29.92, and 27.89 &#8451;, respectively, which were 6.51, 5.76, and 6.0 &#8451; lower than the control group. The root zone temperature of tomato in experimental group was always lower than the highest tolerance temperature (33 &#8451;) of tomato root during the day, and kept the optimum temperature (20-23 &#8451;) throughout the night. All tomato plants in the control group died on the 17th day of the experiment, while plants in the experimental group still grew well and after that they even blossomed and bore fruit. Under this test condition, it took 4.41&times;10⁶ J energy to run the system at a time, and the cooling power per unit area of the thermal planting groove was 510.42 W/m², as the average matrix temperature was reduced by 9.03 &#8451;. It was far less than the energy consumption required for cooling the entire greenhouse air, and it could meet the high demand for precise temperature control of greenhouses in humid and high-temperature environments. In conclusion, in the case of ultra-low energy consumption, the temperature control method of the ecological intelligent planting matrix temperature control system could be used to solve the problems of high temperature tolerance and safe production of greenhouse tomato planting.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Low temperature production
Controlled terms:Control systems - Cooling - Digital storage - Ecology - Energy utilization - Fruits - Greenhouses - Heat exchangers - Intelligent control - Matrix algebra  - Phase change materials - Temperature control - Thermal management (electronics) - Water tanks
Uncontrolled terms:Combined control strategies - Experimental conditions - Greenhouse production - Greenhouse tomatoes - High temperature condition - High-temperature environment - Root zone temperature - Temperature control methods
Classification code:446.1  Water Supply Systems - 454.3  Ecology and Ecosystems - 525.3  Energy Utilization - 616.1  Heat Exchange Equipment and Components - 641.2  Heat Transfer - 722.1  Data Storage, Equipment and Techniques - 731.1  Control Systems - 731.3  Specific Variables Control - 821.4  Agricultural Products - 821.6  Farm Buildings and Other Structures - 921.1  Algebra
Numerical data indexing:Surface_Power_Density 5.10e+02W/m2
DOI:10.11975/j.issn.1002-6819.2020.05.024

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 14>

Accession number:20202108693910
Title:Spatiotemporal variations of future potential evapotranspiration in the Beijing-Tianjin-Hebei region under GFDL-ESM2M climate model
Title of translation:GFDL-ESM2M&#27668;&#20505;&#27169;&#24335;&#19979;&#20140;&#27941;&#20864;&#22320;&#21306;&#26410;&#26469;&#28508;&#22312;&#33976;&#25955;&#37327;&#26102;&#31354;&#21464;&#21270;
Authors:Bi, Yanjie (1, 2); Zhao, Jing (1); Wu, Di (3); Zhao, Yong (2)
Author affiliation:(1) North China University of Water Resources and Electric Power, College of Water Resources, Zhengzhou; 450046, China; (2) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100038, China; (3) China Irrigation and Drainage Development Center, Beijing; 100054, China
Corresponding author:Zhao, Jing(zhaojing19870515@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:141-149
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The temporal and spatial variation characteristics of future potential evapotranspiration (ET<inf>0</inf>) can provide basic data support for agricultural water demand prediction, irrigation management and rational response to climate change. This paper has made the temporal and spatial prediction based on the various parameters, including the average temperature, the maximum temperature, the minimum temperature, total solar radiation, relative humidity and near-surface wind speed, where the 92 grid points were obtained in the Beijing-Tianjin-Hebei region from 1960-2016. The feasibility of climate models was verified using the principle of probability distribution optimization. Using the global climate model of GFDL-ESM2M that provided by the United States (Geophysical Fluid Dynamics Laboratory, GFDL), the SS(Skill Score) value of annual mean temperature could reach 0.86, indicating good applicability for the simulation in the Beijing-Tianjin-Hebei region. The prediction period was set from January 1, 2021 to December 31, 2050, and the climate scenarios were selected RCP(representative concentration pathways)2.6, RCP4.5 and RCP8.5, respectively, representing low, medium and high RCP cases. The temporal and spatial distribution characteristics of the future daily ET<inf>0</inf> and its correlation with climate elements were analyzed using the Penman-Monteith formula based on the measured 92 grid points in the Beijing-Tianjin-Hebei region. The simulated results found that the future ET<inf>0</inf> showed an increasing trend during this period. The ET<inf>0</inf> in the RCP8.5 scenario rose the fastest, with the increment increasing over time, especially in the 2040 period. The summer ET<inf>0</inf> grew the fastest, followed by spring, autumn and winter, meaning that the distribution difference of the seasonal ET<inf>0</inf> will dominate in the future. This phenomenon may cause more severe seasonal droughts. The spatial distribution of ET<inf>0</inf> gradually decreased from southwest to northeast, specifically indicating that Shijiazhuang in the southern plain area had the largest ET<inf>0</inf> (1 207-1 262 mm), while Zhangjiakou and Chengde in the northwest mountainous area had the lowest ET<inf>0</inf> (938-974 mm). There was a high growth rate of ET<inf>0</inf> in the central region, as decreasing from central region to north and south. The average temperature in each climate scenario increased year by year, the wind speed and total solar radiation increased slightly, while the relative humidity decreased. The correlation between ET<inf>0</inf> and the total solar radiation was the most obvious, followed by the highest temperature, all showing an increasing trend from northwest to southeast. The ET<inf>0</inf> had negatively correlation with the relative humidity, but the absolute value of its correlation coefficient increased from northeast to southwest. There was a relatively slight correlation between ET<inf>0</inf> and the wind speed. The correlation coefficient between ET<inf>0</inf> and the total solar radiation showed a declining trend from RCP2.6-RCP8.5 with the increase of the emission concentration, possibly resulting from the large amount of energy consumption. The energy consumption will lead to the increase of the aerosol content in the air and the increase of haze days, leading to the decrease of sunshine hours, and the reduction of the total solar radiation. The negative effect of the reduce in the sunshine hours may exceed the positive effect of the temperature rising. It is possible that the future ET<inf>0</inf> will continue to rise due to the radiation and temperature. The ET<inf>0</inf> increase in the future can deteriorate the water shortages and even severe droughts in the Beijing-Tianjin-Hebei region from 2021 to 2050.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:47
Main heading:Climate models
Controlled terms:Agricultural robots - Climate change - Drought - Energy utilization - Evapotranspiration - Forecasting - Probability distributions - Solar radiation - Spatial distribution - Water supply  - Wind
Uncontrolled terms:Annual mean temperatures - Beijing-tianjin-hebei regions - Distribution optimization - Geophysical fluid dynamics laboratories - Potential evapotranspiration - Spatio-temporal variation - Temporal and spatial distribution - Temporal and spatial variation
Classification code:443  Meteorology - 443.1  Atmospheric Properties - 444  Water Resources - 446.1  Water Supply Systems - 525.3  Energy Utilization - 657.1  Solar Energy and Phenomena - 921  Mathematics - 922.1  Probability Theory
Numerical data indexing:Size 1.21e+00m to 1.26e+00m, Size 9.38e-01m to 9.74e-01m
DOI:10.11975/j.issn.1002-6819.2020.05.016

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 15>

Accession number:20202108693554
Title:Development of the test bench for automatic alignment digging harvest of subterranean crops
Title of translation:&#22303;&#19979;&#20316;&#29289;&#33258;&#21160;&#23545;&#34892;&#25366;&#25496;&#25910;&#33719;&#35797;&#39564;&#21488;&#30740;&#21046;
Authors:Wang, Shenying (1, 2); Hu, Zhichao (1, 2); Chen, Youqing (1, 2); Gu, Fengwei (1, 2); Peng, Baoliang (1, 2); L&uuml;, Xiaolian (3)
Author affiliation:(1) Nanjing Institute of Agricultural Mechanization, Ministry of Agriculture and Rural Affairs, Nanjing; 210014, China; (2) Key Laboratory of Modern Agricultural Equipment, Ministry of Agriculture and Rural Affairs, Nanjing; 210014, China; (3) School of Mechanical and Electrical Engineering, Chuzhou University, Chuzhou; 239000, 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:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:29-37
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to improve the quality and efficiency of the mechanical harvest of subterranean crops, and to solve the problems of high cost, low efficiency, inconvenient data collection and greatly affected by weather on the field test of harvest machines for crops under soil in China, an automatic alignment digging harvest test bench for crops under soil harvesting is designed in this paper. The test bench is mainly composed of a transmission device, speed adjustment device, off-centerline distance adjustment device, root fixed and plant spacing adjustment device, deviation detection device, hydraulic correction actuator and digging simulation device, measurement control system and hydraulic system. The overall structure and working principle of the test bench are briefly analyzed, and the structural design and parameter analysis of key components are especially introduced. A gantry with adjustable front and back distance and height between the deviation detection device and the digging simulation device is designed. Using four-bar linkage, a deviation detection device is designed to detect the distribution of subterranean crops in the soil and transfer it to the controller. An digging simulation device with resistance is designed to simulate the soil resistance of the digging device during the process of digging and harvesting. A device with root fixing, plant spacing and off-centerline distance adjustment is designed to simulate the actual plant spacing, off-centerline distance and other growth conditions in the field. The mathematical relationship between the expansion and contraction of the hydraulic cylinder and the moving distance of the digging mechanism is established. The hardware of the measurement and control system is mainly composed of control box, computer, pressure sensor, flow sensor, displacement sensor, speed sensor, hydraulic solenoid valve, hydraulic cylinder and high-speed camera. The software adopts the fixed dual-threshold dead-zone PD control algorithm. In order to improve the generality of the test bench, it is only to replace the original detecting rod with ridge shaped detecting rod and detecting wheel, and replace the root fixing device with ridge shaped simulating adjusting device when the peanut, potato and other crops completely buried in the soil are dug. Taking the beet harvest as the research object, the plant spacing, off-centerline distance and forward speed as the experimental factors, and the missed digging rate as the index, the comparative tests between the test bentch and field operation was carried out. The test results showed that the leakage rate of the test bentch is 2.33%-2.72%, and the leakage rate of the field test is 2.38%-2.92%. The test bentch has good excavation accuracy, the absolute deviation rate range is 2.10%-6.85%, the average deviation rate is 3.67%, and the larger the leakage rate is, the larger the deviation rate is. This study can provide reference for the design of automatic alignment digging harvest system of underground crops such as beet, radish, potato, etc.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Hydraulic actuators
Controlled terms:Computer control systems - Computer hardware - Crops - Cylinders (shapes) - Efficiency - Harvesting - High speed cameras - Hydraulic equipment - Mechanical actuators - Soils  - Solenoid valves - Structural design
Uncontrolled terms:Deviation detection - Displacement sensor - Expansion and contraction - Experimental factors - Mathematical relationship - Measurement and control systems - Measurement control system - Transmission devices
Classification code:408.1  Structural Design, General - 483.1  Soils and Soil Mechanics - 619  Pipes, Tanks and Accessories; Plant Engineering Generally - 632.2  Hydraulic Equipment and Machinery - 722  Computer Systems and Equipment - 723.5  Computer Applications - 732.1  Control Equipment - 742.2  Photographic Equipment - 821.3  Agricultural Methods - 821.4  Agricultural Products - 913.1  Production Engineering
Numerical data indexing:Percentage 2.10e+00% to 6.85e+00%, Percentage 2.33e+00% to 2.72e+00%, Percentage 2.38e+00% to 2.92e+00%, Percentage 3.67e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.004

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 16>

Accession number:20202108694040
Title:Power generation performance of efficient PERC components with different bracket forms
Title of translation:&#19981;&#21516;&#25903;&#26550;&#24418;&#24335;&#30340;&#39640;&#25928;PERC&#32452;&#20214;&#21457;&#30005;&#24615;&#33021;
Authors:Zou, Han (1); Shao, Ligang (1); Qin, Honggang (1); Qian, Kangwen (1); Cheng, Yuanzhe (1); Li, Xiuxiu (2)
Author affiliation:(1) Huadong Engineering Corporation Limited, Power China, Hangzhou; 311122, China; (2) Jiangsu Provincial Key Laboratory of Solar Energy Science and Technology, School of Energy and Environment, Southeast University, Nanjing; 210096, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:220-225
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, research on power generation performance of PERC (passivated emitter and rear cell) components mostly depends on theoretical calculation or short-term data measurement, and there is a lack of long-term reliable test data. Based on the Tianchang 100 MW photovoltaic power station of Huadong Engineering Corporation Limited Power China, this paper collected the power generation data of fixed-tilt (the positive-south fixed tilt, the inclination angle is 25&deg;) PERC array B1, single axis (the north-south single-axis tracking, the inclination angle is 5&deg;) PERC array B2, fixed-tilt polysilicon array B3 and single-axis polysilicon array B4 in 2018. The data of DC power generation of the test array inverters in 2018 were screened and processed. By analyzing the average daily power generation per watt of four arrays in 2018 and output power per watt of array B2 and array B4 on September 30 in 2018, the superior power generation performance of PERC module was verified. Then, for the further research on PERC modules (array B1 and B2), the average daily power generation per watt with the corresponding power generation gain and the daily power generation per watt in July with the highest irradiance and in December with the lowest irradiance were analyzed. The results showed that PERC component had better power generation performance than polysilicon component in the whole year whether it's single-axis tracking or fixed-tilt, with an average annual power generation gain of 5.7% and 3.7%, respectively, and PERC component maintained a high output power in case of a sudden decrease in irradiance. From March to September, the average daily power generation per watt of the single-axis PERC component was higher, with the average monthly generation gain of 13.4%, and the maximum generation gain reaching 24.9% in July. But in October to February, the fixed-tilt PERC component performed better, with an average monthly generation gain of 8.1%. In July with the highest irradiance and the largest power generation gain, the generation performance of single-axis PERC was significantly better than that of fixed-tilt PERC in sunny days. By contrast, with the lowest irradiance and the smallest power generation gain, the generation performance of fixed-tilt PERC in sunny days was significantly better in December. Because the irradiation in rainy days is mainly diffuse reflection with little tracking value, the power generation of PERC components under the two bracket forms was similar. The superior power generation performance of PERC module in the long-term operation and the power generation characteristics under different bracket forms will make it play an important role in the photovoltaic power plant. Therefore, the selection of modules and brackets in the initial stage of the photovoltaic power station construction should fully investigate the local irradiance resources and climate characteristics. If a place is rich in irradiation resources and sunny days, the single-axis PERC modules can be used preferentially under the same investment cost. The research results can provide technical support for module selection and bracket selection of the photovoltaic power station construction in future.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Power plants
Controlled terms:Irradiation - Photovoltaic cells - Polysilicon
Uncontrolled terms:Climate characteristics - Daily power generations - Diffuse reflection - Engineering corporations - Inclination angles - Photovoltaic power plant - Photovoltaic power stations - Theoretical calculations
Classification code:549.3  Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals
Numerical data indexing:Percentage 2.49e+01%, Percentage 3.70e+00%, Percentage 5.70e+00%, Percentage 8.10e+00%, Power 1.00e+08W, Percentage 1.34e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.025

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 17>

Accession number:20202108694038
Title:Analysis of triaxial shear characteristics of soybean meal based on digital image measurement technology
Title of translation:&#22522;&#20110;&#25968;&#23383;&#22270;&#20687;&#27979;&#37327;&#25216;&#26415;&#30340;&#35910;&#31893;&#21098;&#20999;&#21464;&#24418;&#29305;&#24615;
Authors:Zeng, Changn&uuml; (1); Jin, Nannan (1); Gu, He (1); Zhou, Fei (2)
Author affiliation:(1) College of Civil Engineering and Architecture, Henan University of Technology, Zhengzhou; 450001, China; (2) Personnel Department, Henan University of Technology, Zhengzhou; 450001, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:310-317
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soybean meal is one of the common food raw materials in the world. During storage, sliding or shear failure occurs between particles, which involves the influences of lateral pressure, wall friction and interference between the silo wall. It may lead to the instability, or even damage of the soil structure. An improved triaxial apparatus was studied, especially for the grain materials. The deformation of the whole and local surfaces can be directly measured by the specified image measuring system. Based on the improved triaxial apparatus, a series of triaxial shear experiments of soybean meal were carried out. The effects of confining pressure, porosity and particle breakage of soybean meal on strength and deformation were considered. According to these results, the different deformation stages of the soybean meal were analyzed. The stress-strain model considering the effects of confining pressure, porosity and particle breakage was proposed. Moreover, the corresponding parameters of strength and deformation were also obtained. The results showed that the confining pressure has great effect on mechanical behavior of soybean meal. Under different confining pressures, the stress-strain curves of soybean meal sample showed a softening trend. With the increasing confining pressure, the degree of strength softening increased, while the shear dilatancy gradually decreased. For the same confining pressure, with the decreasing porosity of sample, the peak strength and dilatancy angle of soybean meal gradually increased. The results considering the effect of different crushing degrees on the particles were also compared. It was found that the influence of confining pressure on particle crushing was greater than that of porosity. After crushing of soybean meal, the peak shear strength was greatly increased, while the volume of the sample became a complete shear shrinkage condition. The larger the applied confining pressure, the more obvious shear shrinkage behavior occurred. The results showed that particle crushing had a great influence on the strength and deformation of soybean meal. The local surface deformation of the specimen was exhibited by the digital image measurement technology. The deformation process of the specimen was described in the strain field contour, including the stage of the failure band during shearing. Based on the analysis of local deformation, the stress-strain curve of soybean meal can be divided into three stages: pre-failure, failure and residual stage. The stress-strain models of the three stages were proposed, involving the corresponding strength and deformation parameters. During the pre-failure stage, the non-linear constitutive model can satisfy the stress-strain curve of soybean meal. While in the failure and residual stage, a critical stage model was proposed. The experimental results can provide the basic parameters for the storage design of soybean meal materials.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Stress-strain curves
Controlled terms:Crushing - Deformation - Porosity - Rock pressure - Shrinkage - Walls (structural partitions)
Uncontrolled terms:Confining pressures - Deformation parameter - Deformation process - Different confining pressures - Digital image measurement - Mechanical behavior - Peak shear strength - Stress-strain model
Classification code:408.2  Structural Members and Shapes - 502.1  Mine and Quarry Operations - 931.2  Physical Properties of Gases, Liquids and Solids - 951  Materials Science
DOI:10.11975/j.issn.1002-6819.2020.05.036

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 18>

Accession number:20202108694051
Title:Construction of land classification system and land type identification for territorial spatial planning based on multi-source data
Title of translation:&#22522;&#20110;&#22810;&#28304;&#25968;&#25454;&#30340;&#22269;&#22303;&#31354;&#38388;&#35268;&#21010;&#29992;&#22320;&#20998;&#31867;&#20307;&#31995;&#26500;&#24314;&#21644;&#22303;&#22320;&#31867;&#22411;&#35782;&#21035;
Authors:Zhang, Hebing (1); Li, Minghui (1); Zhang, Qinglei (1)
Author affiliation:(1) School of Surveying and Landing Information Engineering, Henan Polytechnic University, Jiaozuo; 454000, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:261-269
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Accurate, reliable and timely acquisition of data for spatial planning of land are prerequisite for the "dual evaluation" and "three types of spatial planning" division and pattern optimization, and the preparation of land and spatial planning. Current data of land surveys, urban and rural land usage, and various geographical classification systems have different classification standards and many data sources, so it is urgent to optimize of the land-use classification system, construct land classification conversion rules and identification methods based on multi-source data. This paper preliminary investigates the territorial planning and land classification system using the inductive comparison method. Compared with the former planning, the latest national territory planning system comprise by major functional area, land utilization and urban rural land planning. As the identification of territory classification is the basic data for land geo-spatial planning. This paper takes Hebi, Henan for example to construct the terrestrial spatial classification system and identifying terrestrial space types based on multi-source data. Hebi has large potential improvement and optimization in terms of ecological transformation and development motivation. Combined with the third national investigation of the territory classification, inductive comparison method is used to explore the classification system of territorial space and land transformation and convergence rules of the existing spatial classification system to achieve effective consecutive connection between municipal scale and multiple classification system based on the comprehensive comparative analysis method. Steps are as follows : firstly, unified coordinate system and attribute structure for multi-source data; secondly, through the spatial superposition analysis of GIS, the spatial superposition analysis of unified good data is carried out, and the reference unit of land class identification under multi-source data is constructed, so that each polygon unit has multi-source data attribute structure; thirdly, the criterion of national land class identification is constructed to solve the problem of land classification conversion conflict of multi-source data; finally, the convergence criterion and combination recognition of land classification are modified based on remote sensing image data. The results show that the land use spatial classification system is divided into four first-level categories: ecological protection land, land for agricultural production and living, land for urban development and regional facility land, 12 second-level categories and 45 third-level categories. This paper establishes the criteria of land class connection conversion and the method of fusion identification, and completes the identification of land classification for the land space planning based on the multi-source data. In 2017, the total land area of Hebi City is 2140.43 km², the area of ecological protection land, land for agricultural production and living, land for urban development and the facility land are 453.95, 1531.53, 121.06 and 33.89 km², respectively. This paper provides data support for Hebi City to carry out "ecological/agricultural/urban three types of space" division and pattern optimization, "dual evaluation", and planning.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Classification (of information)
Controlled terms:Agricultural robots - Ecology - Forestry - Land use - Remote sensing - Rural areas - Spatial variables measurement - Urban growth
Uncontrolled terms:Agricultural productions - Classification standard - Ecological transformation - Landuse classifications - Multiple classification systems - Remote sensing images - Spatial classification - Superposition analysis
Classification code:403  Urban and Regional Planning and Development - 403.1  Urban Planning and Development - 454.3  Ecology and Ecosystems - 716.1  Information Theory and Signal Processing - 943.2  Mechanical Variables Measurements
Numerical data indexing:Area 1.21e+08m2, Area 2.14e+09m2, Area 3.39e+07m2
DOI:10.11975/j.issn.1002-6819.2020.05.031

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 19>

Accession number:20202108693904
Title:Improving hyperspectral detection accuracy of total bacteria in prepared chicken using optimized BP neural network
Title of translation:&#20248;&#21270;BP&#31070;&#32463;&#32593;&#32476;&#25552;&#39640;&#39640;&#20809;&#35889;&#26816;&#27979;&#35843;&#29702;&#40481;&#32905;&#33740;&#33853;&#24635;&#25968;&#31934;&#24230;
Authors:Wang, Haoyun (1, 2); Song, Jin (1); Pan, Leiqing (3); Yuan, Peisen (1); Guo, Zhenhuan (4); Xu, Huanliang (1, 2)
Author affiliation:(1) College of Information Science & Technology, Nanjing Agricultural University, Nanjing; 210095, China; (2) Postdoctoral Mobile Station of Agricultural Engineering, Nanjing Agricultural University, Nanjing; 210031, China; (3) College of Food Science & Technology, Nanjing Agricultural University, Nanjing; 210095, China; (4) Jiangsu Yike Food Group Company Limited, Suqian; 223800, China
Corresponding author:Xu, Huanliang(huanliangxu@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:302-309
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Meat spoilage is a relatively complicated process, in which microorganisms increase nonlinearly. As a non-linear model, BP neural network has strong generalization ability and fitting ability, but there are some shortcomings in the application, such as slow convergence speed, easy to fall into local minima and overfitting. Thus an optimized BP neural network was proposed. Prepared chicken was stored in a refrigerator at 4 &#8451;, and 240 samples were collected. After obtaining 400-1000 nm hyperspectral images of each prepared chicken sample, sub-samples were randomly selected from each homogenized sample to determine the total bacteria. Then, the spectral data was preprocessed by different methods such as differentiation, standard normalized variate, and multiplicative scatter correction. The PLSR model was cross-validated by the leave-one-out method, and the best preprocessing method was determined based on RMSE<inf>CV</inf>(root mean square error of cross validation). After that, based on the pre-processed spectral information, 34 characteristic bands were extracted by CARS (competitive adaptive reweighted sampling) algorithm. Finally, the spectral values corresponding to the full-band and filtered characteristic bands were used as the input of the BP (back propagation) neural network, and the total bacteria was used as the output of the BP neural network. Bird swarm algorithm (BSA) and immune algorithm (IA) optimization were used to optimize the initial weight and threshold of the BP neural network. The prediction models of the total bacteria were established by using BP, BSA-BP, IA-BP, and BSA-IA-BP. The results showed that: 1) by introducing the IA algorithm's immune operation, after iterative stabilization, the total fitness of BSA-IA-BP was significantly lower than BSA-BP based on training samples. This showed that the search ability of the BSA-IA fusion algorithm was improved, which could effectively prevent the BSA algorithm from falling into a local optimum in the later stage. At the same time, among the four models of BP, IA-BP, BSA-BP, and BSA-IA-BP, the BSA-IA-BP model had the best prediction accuracy and convergence speed. Among them, the BSA-IA-BP model in the characteristic band had the highest prediction accuracy. The R<inf>P</inf> (the correlation coefficient), RMSE<inf>P</inf> (the root mean square error) and RPD (the residual predictive deviation) of the prediction set was 0.93, 0.31 lg(CFU/g), 2.68, respectively. 2) By comparing the characteristic band and the full band, the overall prediction effect of the characteristic band was better than the full band, which indicating that the CARS algorithm could effectively delete the wavelengths, reduced redundant information interference, and improved the model prediction efficiency. In general, the use of hyperspectral technology for non-destructive testing of the total bacteria in prepared chicken was feasible, which can provide technical support for the online testing of prepared chicken.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:35
Main heading:Backpropagation
Controlled terms:Animals - Bacteria - Coherent scattering - Forecasting - Iterative methods - Mean square error - Neural networks - Nondestructive examination - Predictive analytics - Spectroscopy
Uncontrolled terms:BP (back propagation) neural network - Correlation coefficient - Generalization ability - Hyperspectral detections - Leave one out methods - Multiplicative scatter correction - Non destructive testing - Root mean square errors
Classification code:711  Electromagnetic Waves - 723.4  Artificial Intelligence - 921.6  Numerical Methods - 922.2  Mathematical Statistics
Numerical data indexing:Size 4.00e-07m to 1.00e-06m
DOI:10.11975/j.issn.1002-6819.2020.05.035

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 20>

Accession number:20202108693534
Title:Design and experiment of a device for rapeseed strip aerial seeding
Title of translation:&#27833;&#33756;&#25104;&#26465;&#39134;&#25773;&#35013;&#32622;&#35774;&#35745;&#19982;&#35797;&#39564;
Authors:Huang, Xiaomao (1, 2); Xu, Huwei (1); Zhang, Shun (1); Li, Wencheng (1, 2); Luo, Chengming (1, 2); Deng, Yufei (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China; (2) Key Laboratory of Agricultural Equipment in Mid-lower Yangtze River, Ministry of Agriculture and Rural Affairs, Wuhan; 430070, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:78-87
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:UAV can realize track planning and automatic navigation flight due to its small size and flexible operation performance. It has been widely used in the agricultural field for its advantages of high obstacle crossing performance, stability and operation efficiency comparing to ground machines. At present, most UAV based aerial seeding devices use core parts like horizontal centrifugal disc or outer groove wheel to scatter seeds, fertilizers and other materials in the air. Due to the high seeding height and the disturbance of UAV rotor air flow, the randomness of material particles after landing is very large, and they are generally scattered on the whole plane. Although it has high seeding efficiency, it belongs to a relatively extensive seeding mode for that it is not easy to control the seed uniformity affected by many factors. In view of the above problems, a kind of rapeseed aerial seeding device based on an electrically driven centrifugal seeding meter was designed and tested for XAG P20 which is a commercial crop protection UAV. The aerial seeding device can seed in lines instead of wide area, and is more conducive to improve the uniformity of seedlings and the convenience of field management during crop growth. In this study, we first improved the design of the concave cone centrifugal seed metering device and determined the structural parameters of the key components such as seed metering tray and seed metering port. Then, based on ANSYS Fluent simulation software, the distribution of downwash air flow field of the XAG P20 drone was analyzed. An auxiliary seed guiding device used in combination with the centrifugal seed metering device was proposed and built. Three experiments including the seed metering performance test, the prototype test and the field test were carried out to analyze and study the functions of the aerial seeding device. The results showed that the total seeding quantity per unit time increased when the seeding rotation speed increased from 40 to 190 r/min, and the maximum total seeding quantity reached 179.65 g/min at 190 r/min, which can meet the requirements of 0-5m/s operation speed of the drone; the variation coefficient of consistency and stability of apiecerow seeding quantity decreased first and then increased, which were distributed in the range of 4.5%-12.6% and 0.7%-6.2% respectively. The damage rate of seeds increased gradually, but all of which were within 2%. The prototype test showed that when the height of the seed guiding device was in the range from 1.5 to 2.5 m, the width of the seed strips was less than 1/4 of the row spacing, and the striping index of the seed had no significant correlation with it. However, considering the operational risk and convenience of the personnel in the actual operation process, the height of 2m was selected as the appropriate height of the seed guiding device. Under that condition, the field experiment results showed that the strip index was 35.0%, the variation coefficient of sowing uniformity was 19.26%. The device designed in this study can meet the technical requirements of rape drilling.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Antennas
Controlled terms:Agricultural robots - Air - Centrifugation - Computer software - Crops - Drones - Efficiency - Oilseeds - Particle size analysis - Pneumatic materials handling equipment
Uncontrolled terms:Agricultural fields - Automatic navigation - Consistency and stabilities - Operation efficiencies - Seed metering devices - Structural parameter - Technical requirement - Variation coefficient
Classification code:632.4  Pneumatic Equipment and Machinery - 723  Computer Software, Data Handling and Applications - 802.3  Chemical Operations - 804  Chemical Products Generally - 821.4  Agricultural Products - 913.1  Production Engineering - 951  Materials Science
Numerical data indexing:Mass_Flow_Rate 2.99e-03kg/s, Velocity 0.00e+00m/s to 5.00e+00m/s, Percentage 1.93e+01%, Percentage 2.00e+00%, Percentage 3.50e+01%, Percentage 4.50e+00% to 1.26e+01%, Percentage 7.00e-01% to 6.20e+00%, Rotational_Speed 1.90e+02RPM, Rotational_Speed 4.00e+01RPM to 1.90e+02RPM, Size 1.50e+00m to 2.50e+00m, Size 2.00e+00m
DOI:10.11975/j.issn.1002-6819.2020.05.009

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 21>

Accession number:20202108693852
Title:Characteristics of soil particle size distribution and its effect on dust emission in Taklimakan Desert
Title of translation:&#22612;&#20811;&#25289;&#29595;&#24178;&#27801;&#28448;&#22303;&#22756;&#31890;&#24230;&#20998;&#24067;&#29305;&#24449;&#21450;&#20854;&#23545;&#31881;&#23576;&#37322;&#25918;&#30340;&#24433;&#21709;
Authors:Yang, Xinghua (1); Kang, Yongde (1); Zhou, Chenglong (1); Huo, Wen (1); Yang, Fan (1); Pan, Honglin (1); Meng, Lu (1); He, Qing (2)
Author affiliation:(1) Institute of Desert Meteorology, China Meteorological Administration, Urumqi; 830002, China; (2) Xinjiang Meteorological Bureau, Urumqi; 830002, China
Corresponding author:He, Qing(qinghe@idm.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:167-174
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Transport of dust sand caused by wind erosion is a serious problem in many arid regions in the world, and it plays an important role in global biogeochemical cycle. The dust induced by transport of aeolian sand can affect atmospheric radiation balance, climate, environment, air quality and human health. It has hence attracted increased attention in various areas ranging from geomorphology and climatology to meteorology and ecological-environmental science. In addition to its natural origin, dust could also be instigated by anthropogenesis activities due to desertification. However, the relative contribution of the two origins is still an issue remaining elusive. In addition, being able to accurately estimate the potential of a dust source is crucial to evaluating the influence of desertification and climate change on dust flux. The Taklimakan desert(TD) is the second largest shifting sand desert in the world, with about 85% made up by shifting sand dunes. It is an important source of the dusts seen in China. Understanding particle size distribution of the sand and dust emission is helpful to evaluate quality of the atmospheric environment and the consequence for climate at regional scale. We collected 138 samples from soil surface based on spatial distribution and types of the surfaces including farmland, dune and desert. Particle sizes of each sample was analyzed using the Mastersizer 2000 laser particle size analyzer, and the associated dust release flux was calculated using the DPM model. The particle size distribution of the microaggregates in each sample was obtained to elucidate its potential influence on dust release flux. The results showed that: 1) The content of silt and clay in the 138 samples was least, accounting for 10% to 18% of the total particles in the mobile sand dunes, and 20% to 30% of the total particles in the sand ridges (e.g., sandy soil and sandy-sandy loams). Most samples taken from farmland (e. g., oasis and forest belt) are meadow soil, with silt and clay content being 50%-80%, differing from the silt and clay content in samples taken from the Gobi (desert area). 2) Fine sand and silty-fine sand are the smaller particles in the surface soil and can be divided into three groups, each described by a lognormal distribution: silt-fine sand group, fine sand group and coarse sand group, with median particle size being 90, 225 and 500 &mu;m, and the standard deviation being 1.02, 1.53 and 1.08, respectively, accounting for 30%, 49% and 21% respectively. 3) Emission of silt-fine sand and fine sand is most potential, followed by medium-coarse sand. The coarse sand is least to emit; the difference between the maximum and the minimum emission was in the order of 10^-2 &mu;g/(m²&bull;s) in magnitude. The results reflect the difference in dust emission from different soil surfaces and they are greatlyimportant for quantitative assessment of dust emission in the studied region and beyond.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:41
Main heading:Sand
Controlled terms:Air quality - Atmospheric movements - Atmospheric radiation - Biogeochemistry - Climate change - Dust - Farms - Landforms - Light transmission - Particle size  - Particle size analysis - Silt - Size distribution
Uncontrolled terms:Atmospheric environment - Biogeochemical cycle - Environmental science - Laser particle size analyzer - Log-normal distribution - Median particle size - Quantitative assessments - Relative contribution
Classification code:443.1  Atmospheric Properties - 451.1  Air Pollution Sources - 451.2  Air Pollution Control - 481.1  Geology - 481.2  Geochemistry - 483.1  Soils and Soil Mechanics - 741.1  Light/Optics - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2  Mathematical Statistics - 951  Materials Science
Numerical data indexing:Percentage 1.00e+01% to 1.80e+01%, Percentage 2.00e+01% to 3.00e+01%, Percentage 2.10e+01%, Percentage 3.00e+01%, Percentage 4.90e+01%, Percentage 5.00e+01% to 8.00e+01%, Percentage 8.50e+01%, Size 2.25e-04m, Size 5.00e-04m
DOI:10.11975/j.issn.1002-6819.2020.05.019

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 22>

Accession number:20202108693551
Title:Effect of energy storage materials on performance of solar heat pump system with inserted heat pipe in winter
Title of translation:&#33988;&#33021;&#26448;&#26009;&#23545;&#20869;&#25554;&#28909;&#31649;&#24335;&#22826;&#38451;&#33021;&#28909;&#27893;&#31995;&#32479;&#20908;&#23395;&#24615;&#33021;&#30340;&#24433;&#21709;
Authors:Wu, Wei (1); Xia, Man (1); Yin, Zhengyu (1); Gao, Xu'na (1); Huang, Jinyan (1); Qin, Zhixuan (1)
Author affiliation:(1) Engineering Laboratory for Energy System Process Conversion and Emission Control Technology of Jiangsu Province, School of Energy and Mechanical Engineering, Nanjing Normal University, Nanjing; 210042, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:226-232
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to make full use of solar energy and improve the energy efficiency of solar heat pump system, an energy storage solar heat pump water heating system with inserted oscillating heat pipe is proposed, which integrates solar collector, energy storage tank and oscillating heat pipe together reasonably and effectively. The system can store solar energy with the phase change materials (PCM) filled in the collector, transfer heat efficiently by oscillating heat pipe and switch operation mode according to solar radiation, and can realize the maximum utilization of solar energy in different seasons. In summer, enough heat is transferred or stored during the day to release at night by PCM in solar collector, which is directly used to heat the circulating water through the oscillating heat pipe heat exchanger. In winter, the heat transferred or stored during the day to release at night by PCM in solar collector is low, and the heat is transferred to the heat pump evaporator by the oscillating heat pipe heat exchanger to improve the evaporation temperature of the heat pump, and thus the overall performance of the system is improved. A test rig has also been established for the performance measurement of energy storage solar heat pump water heating system with inserted oscillating heat pipe. Paraffin is chose as phase change material of the system under the consideration of capacity, phase change temperature and latent heat of phase change. Experimental study has been carried out for two years under winter conditions in Nanjing, one year for the test rig without PCMs and another year with PCMs. Under similar environmental conditions (solar radiation intensity, fluctuation and ambient temperature), the variations of the instantaneous collecting efficiency, average collecting efficiency, COP (coefficient of performance) and water temperature of the system filling or not filling PCM with the fluctuation of solar radiation are compared and studied. The comparison and experimental results show that in winter daytime under similar solar radiation intensity, fluctuation and ambient temperature, the instantaneous collecting efficiency fluctuation with PCM is 61.5% less than that of the system without PCM, which can overcome the instantaneous influence of the fluctuation of solar radiation intensity on the system. Meanwhile the average collecting efficiency with PCM is 25.5% higher than that of the system without PCM. At winter night, under similar operation conditions, COP of the system filled with PCM is over 3.0, which is nearly twice as high as that of the system without PCM, and make water temperature reach 50 &#8451; in a shorter time, shortening the time by more than 20%. The results can provide theoretical basis for the popularization and application of solar energy heat pump system.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Collector efficiency
Controlled terms:Coefficient of performance - Energy storage - Heat pipes - Heat pump systems - Heating equipment - Hot water distribution systems - Phase change materials - Pumps - Solar energy - Solar heating  - Solar radiation - Solar water heaters - Storage (materials) - Temperature
Uncontrolled terms:Collecting efficiency - Environmental conditions - Evaporation temperature - Oscillating heat pipes - Performance measurements - Phase change temperature and latent heats - Solar radiation intensity - Water heating systems
Classification code:525.7  Energy Storage - 616.1  Heat Exchange Equipment and Components - 618.2  Pumps - 619.1  Pipe, Piping and Pipelines - 641.1  Thermodynamics - 657.1  Solar Energy and Phenomena - 694.4  Storage - 702.3  Solar Cells
Numerical data indexing:Percentage 2.00e+01%, Percentage 2.55e+01%, Percentage 6.15e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.026

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 23>

Accession number:20202108694048
Title:Parameter calibration of discrete element simulation model for latosol particles in hot areas of Hainan Province
Title of translation:&#28023;&#21335;&#28909;&#21306;&#30742;&#32418;&#22756;&#39063;&#31890;&#31163;&#25955;&#20803;&#20223;&#30495;&#27169;&#22411;&#21442;&#25968;&#26631;&#23450;
Authors:Xing, Jiejie (1); Zhang, Rui (1); Wu, Peng (1); Zhang, Xirui (1); Dong, Xuehu (2); Chen, Ying (3); Ru, Shaofeng (1)
Author affiliation:(1) School of Mechanics and Electrics Engineering, Hainan University, Haikou; 570228, China; (2) Tropical Agricultural Machinery Research Institute, Chinese Academy of Tropical Agricultural Sciences, Zhanjiang; 524091, China; (3) University of Manitoba, Winnipeg; R3T 2N2, Canada
Corresponding author:Zhang, Xirui(zhangxirui_999@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:158-166
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Latosol is the zonal soil of tropical rainforest or seasonal rainforest in the southernmost part of China. Compared with ordinary soil, latosol has stronger expansibility, flow plasticity and water holding capacity. In the cultivation of latosol, there are many problems, such as high resistance, low efficiency, and serious soil adhesion of parts touching the soil. In recent years, with the continuous improvement of agricultural mechanization level, discrete element method is gradually applied in the field of agricultural engineering. But the existing research is mainly aimed at the soil with weak viscosity, such as sandy soil, dry soil or rock soil. These research results are not suitable for the latosol, and there are few researches on the parameter calibration of the discrete element simulation model of latosol. In this paper, the simulation contrast test of soil repose angle and soil breaking resistance, and calibrate the contact parameters of the discrete element model of latosol had been carried out with "Hertz-Mindlin with JKR" contact model in the EDEM software. The actual repose angle of latosol with moisture content of 7.8% was measured to be 32.35 &deg;. The recovery coefficient, static friction coefficient and rolling friction coefficient between latosol, latosol and contact parts were measured by design test. Seven coefficients were selected as test factors by Design-expert software and factor level was set. The repose angle was taken as test index and design parameter calibration test was carried out. Using Plackett-Burman Design test to determine the key factors affecting the repose angle of latosol include recovery coefficient of latosol-latosol, rolling friction coefficient of latosol-latosol, rolling friction coefficient of latosol-28MnB5 plate and surface energy. Using regressive analysis by Box-Behnken to fit the test results, and the repose angle regression model was obtained. The regression variance analysis of the model showed that the regression model was very significant, and the repose angle could be predicted according to the model. Taking the actual repose angle of latosol as the objective value, the regression model was optimized, and the optimal values of four significant factors were obtained: latosol-latosol recovery coefficient 0.40, latosol-latosol rolling friction coefficient 0.07, latosol-28MnB5 plate rolling friction coefficient 0.24, JKR surface energy 4.31 J/m². The simulation experiment of the repose angle of EDEM was designed, and the image of the simulated repose angle was processed by python. The relative error between the simulated repose angle and the measured repose angle was 0.62%. The soil tank model was established to simulate the movement process of the breaking blade in the latosol, and the test was carried out to compare the fitting situation of the change of the breaking resistance. Comparion of soil breaking fitting resistance curve in numeral simulation and test, showed that the calibration of the parameters of the discrete element simulation model of latosol was accurate and reliable.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Soils
Controlled terms:Agricultural robots - Calibration - Cultivation - Curve fitting - Interfacial energy - Machinery - Recovery - Regression analysis - Rolling - Software testing  - Stiction
Uncontrolled terms:Agricultural mechanization - Continuous improvements - Discrete element modeling - Discrete element simulation - Plackett-Burman designs - Recovery coefficients - Static friction coefficient - Water holding capacity
Classification code:483.1  Soils and Soil Mechanics - 723.5  Computer Applications - 821.3  Agricultural Methods - 921.6  Numerical Methods - 922.2  Mathematical Statistics
Numerical data indexing:Percentage 6.20e-01%, Percentage 7.80e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.018

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 24>

Accession number:20202108693605
Title:Integrated water and nitrogen management model of WHCNS_Veg for greenhouse vegetable production system
Title of translation:&#35774;&#26045;&#33756;&#22320;WHCNS_Veg&#27700;&#27694;&#31649;&#29702;&#27169;&#22411;
Authors:Liang, Hao (1, 2); Hu, Kelin (2); Sun, Yuan (3); L&uuml;, Haofeng (2); Lin, Shan (2)
Author affiliation:(1) College of Agricultural Engineering, Hohai University, Nanjing; 210098, China; (2) College of Land Science and Technology, China Agricultural University, Key Laboratory of Arable Land Conservation in North China, Beijing; 100193, China; (3) Agricultural Information Institute, Chinese Academy of Agricultural Sciences, Beijing; 100081, China
Corresponding author:Hu, Kelin(hukel@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:96-105
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Excessive water and nitrogen (N) input and shallow root systems have led to serious N loss in greenhouse vegetable production system (GVPS), thereby threatening the soil and water-body environments. Identifying the fates of water and N is crucial to develop best management strategies in intensive GVPS. Soil-crop models are important as a water and N management tool to tradeoff crop yield and environmental cost. The objectives of this study were to develop a scientific water and N management tool for intensive GVPS in China, and evaluate the model performance in the simulating water dynamic, N fate and vegetable growth under different water and N management practices in China. In this study, based on the EU-Rotate_N model, a vegetable growth module was developed and fully incorporated into a soil water heat carbon nitrogen simulator (WHCNS). The coupled model, i.e., WHCNS_Veg, combined the soil module of the WHCNS model with the vegetable growth module of the EU-Rotate_N model. The key processes included soil movement, soil water evaporation, crop transpiration, soil N transport and transformation (net N mineralization, nitrification, ammonia volatilization, and denitrification) and vegetable growth. Two field experiments conducted in Shouguang city, Shandong province, and Tianjin city, Hebei province were used to test the coupled WHCNS_Veg model. Cucumber and tomato were planted in solar greenhouses at Shouguang and Tianjing experiments, respectively. Similar irrigation and fertilization management practices were both setup in the two experiments: 1) Furrow irrigation with conventional N fertilizer (farmer's practice), FP; 2) Drip irrigation with optimal N fertilizer, OPT; 3) FP plus crop residues, FPR; and 4) OPT plus crop residues, DOR. Field experiment data including soil water (soil water content and matrix potential), soil N (nitrate concentration and nitrate leaching), plant N uptake, and marketable fresh yield under different water and N management practices were collected in the experiments. Results showed that the WHCNS_Veg model performed better in crop growth simulation than soil water and N dynamic simulation, with normalized root mean square error (nRMSE) not higher than 12.1%, index of agreement (IA) not less than 0.934 and Nash-Sutcliffe efficiency (NSE) not less than 0.829 for simulation of cucumber and tomato yield and plant N uptake. Soil water content had the highest simulation accuracy. The nRMSE, IA and NSE values for soil water content simulation were 6.2%-9.1%, 0.851-0.960 and 0.477-0.846, respectively. For soil nitrate concentration and nitrate leaching, the nRMSE values were 22.2%-40.1% and 4.6-26.0%, respectively, and the NSE values were -0.810-0.636 and 0.442-0.956, respectively. It indicated that the model simulation results are within the acceptable range. However, WHCNS_Veg model showed relative low simulation accuracy in soil matrix potential under drip irrigation condition, with nRMSE, IA and NSE values ranged from 22.9%-30.1%, 0.223-0.846, and -6.344-0.113, respectively. It indicated that the model has to be improved to simulate soil matrix potential under drip condition. In general, the coupled WHCNS_Veg model gives satisfactory results for soil water and N dynamics simulations as well as vegetable growth simulations. It has great potential to simulate and analyze water and N fates, and vegetable growth for the intensive greenhouse vegetable production in China.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Soil surveys
Controlled terms:Agricultural wastes - Ammonia - Crops - Fertilizers - Fruits - Greenhouses - Irrigation - Leaching - Mean square error - Nitrates  - Soil moisture - Soil testing - Transpiration - Vegetables
Uncontrolled terms:Ammonia volatilization - Greenhouse vegetables - Management strategies - Nitrate concentration - Root mean square errors - Soil nitrate concentrations - Soil water evaporation - Transport and transformation
Classification code:461.9  Biology - 483.1  Soils and Soil Mechanics - 802.3  Chemical Operations - 804  Chemical Products Generally - 804.2  Inorganic Compounds - 821  Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2  Mathematical Statistics
Numerical data indexing:Percentage 1.21e+01%, Percentage 2.22e+01% to 4.01e+01%, Percentage 2.29e+01% to 3.01e+01%, Percentage 4.60e+00% to 2.60e+01%, Percentage 6.20e+00% to 9.10e+00%
DOI:10.11975/j.issn.1002-6819.2020.05.011

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 25>

Accession number:20202108693531
Title:Measurement and coupling analysis of land carrying capacity of coastal areas in the Yangtze River Delta
Title of translation:&#38271;&#19977;&#35282;&#27839;&#28023;&#22320;&#21306;&#22303;&#22320;&#25215;&#36733;&#21147;&#27979;&#24230;&#19982;&#32806;&#21512;&#20998;&#26512;
Authors:Wang, Manman (1, 2); Zhang, Hongyan (3); Zhang, Youguang (1); Lin, Mingsen (1); Gong, Peng (2)
Author affiliation:(1) National Satellite Ocean Application Service, Beijing; 100081, China; (2) Department of Earth System Science, Tsinghua University, Beijing; 100084, China; (3) School of Economics, Beijing Technology and Business University, Beijing; 100048, China
Corresponding author:Zhang, Hongyan(zhybjgs@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:281-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Understanding the difference in land carrying capacity and its evolution incoastal areas in the Yangtze River Delta is important for optimally allocatingits land resources and sustaining its social and economic development. This paper presents an evaluation index system for calculating the land carrying capacity of these areasusing the support- pressure concept. We analyzed the spatiotemporal change in land carrying capacity of 11 coastal areas in the delta in 2000, 2010 and 2018, using a combination of the entropy model, the coupling coordination-degree model and the land capacity carry model. The data used in the models were obtained from remote sensing image interpretation and the national socioeconomic statistics database. The evaluation index system could be used to complement the existing evaluation research results, especially in the context of the development model of the Yangtze River Delta urban agglomeration. It could further improve our understanding of the evolutionary change in land carrying capacity in the coastal areas. Our results indicated that: 1) The coastal areas were overloaded in all three years, with the stress imposed to the lands more than what the lands could support. The supporting force index had been wavily increased while the pressure index had been in decline over the three years. In terms of support evaluation factors, the "construction investment support" was significantly higher than the "land resources basic support" and "policy control support". In terms of evaluation factors for pressure, the mean measurement values were ranked in "land use disturbance pressure" < "coastal disaster damage pressure" <"socioeconomic development pressure". 2) Among the total 33 coastal areas sampled in each of the three years, nineareas had a land carrying capacity index >1, indicating that the surplus status of the coastal areas accounted for 27.3%. The support and pressure levels remained unchanged for Shanghai and Hangzhou, but for other areas they showed continuous rise, decline, or alternate rise and fall. 3) Areas with coupling degree between 0.9 and 1.0 accounted for 97% of the total areas, all in coordinated coupling period. The land support-pressure coordination degree had four types: moderately imbalanced, basically coordinated, moderately coordinated and highly coordinated. Spatially, most coordination types in Jiangsu were moderately imbalanced, and Zhejiang were dominated by basically coordinated with a spatial pattern of "low in north and high in south". The coastal areashad formed a spatial pattern that converged toward Shanghai in all directions. 4) The land carrying capacity of all coastal areas in the Yangtze River Delta was overloaded, but the degree of the overload appeared to have been weakening. The studied areas in each of the three years were in a state with overload and surplus coexisting. The capacity showed a spatial pattern of "overload in south-north and surplus in center" in Jiangsu province, "global surplus" in Shanghai, and "surplus in north and overload in south" in Zhejiang province. The spatial variation of land carrying capacity in the coastal areas in the Yangtze River Delta showed that the capacity in 2000 could be divided into four states: high surplus, low surplus, low overload and high overload, while in 2010 and 2018 there were only three states.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Coastal zones
Controlled terms:Economic and social effects - Land use - Remote sensing - Rivers
Uncontrolled terms:Construction investments - Evaluation index system - Land use disturbances - Remote sensing image interpretations - Social and economic development - Socio-economic development - Spatio-temporal changes - Urban agglomerations
Classification code:403  Urban and Regional Planning and Development - 471  Marine Science and Oceanography - 971  Social Sciences
Numerical data indexing:Percentage 2.73e+01%, Percentage 9.70e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.033

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 26>

Accession number:20202108693774
Title:Rheology and dewaterability of sludge during anaerobic digestion
Title of translation:&#27745;&#27877;&#21388;&#27687;&#28040;&#21270;&#36807;&#31243;&#30340;&#27969;&#21464;&#35268;&#24459;&#19982;&#33073;&#27700;&#24615;&#33021;
Authors:Cao, Xiuqin (1, 2); Wang, Haoran (2); Jiang, Kun (3); Liu, Ting (2); Zhu, Kaijin (4); Ren, Xiaoli (4)
Author affiliation:(1) Key Laboratory of Urban Storm Water System and Water Environment Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing; 100044, China; (2) School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing; 100044, China; (3) China Railway Shanghai Design Institute Group Co. LTD, Shanghai; 200070, China; (4) Tai Yuan Institute of Technology, Taiyuan; 030008, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:233-240
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biogas is one of the most hopeful renewable energy sources in the world. The anaerobic digestion (AD) process has been studied intensively over the last few decades, its application on biomass and solid waste digestion, as well as in wastewater treatment, agriculture. In order to gain a comprehensive insight, the interactive relationship between substrate rheology, physicochemical properties, and biogas production as well sludge dewaterability was investigated. Anaerobic digestion experiments were performed on conventional sludge and low temperature thermal hydrolysis pretreatment sludge. The experiment lasted for 20 days. Rheological indicators and physical and chemical indicators of conventional sludge and low temperature thermal sludge were determined by the rotational viscometer method and standard method during anaerobic digestion. The results showed that the pH value was maintained 6.8 to 7.9, which was within the allowable range of anaerobic digestion. The concentration of Free Ammonia (FAN) is between 10-130 mg/L, which was lower than the inhibition level of anaerobic digestion. The content of VFAs (Volatile Fatty Acid) in low temperature thermal hydrolysis sludge was higher than that in conventional anaerobic digestion sludge. The final Volatile solids removal level (VS<inf>r</inf>) of low temperature thermal hydrolysis-anaerobic digestion reached was 48.3%, and it was higher than conventional anaerobic digestion (44.6%). The dewaterability of sludge increased with the anaerobic time during the AD, and the low temperature thermal pretreatment increased the dewaterability of digestion by 1.59%, which demonstrated the improved dewaterability of low temperature thermally hydrolysis treated sludge. After the conventional anaerobic digestion and the low temperature thermal digestion, the yield stress of the sludge decreased by 64.51% and 71.47%, respectively. The consistency coefficient decreased by 90.94% and 92.83%, respectively. It implied the sludge fluidity significantly enhanced. During the whole digestion process, the VS/ Total solids (TS) and yield stress (&tau;<inf>0t</inf>) showed a logarithmic downward trend with time. Using the linear equation fitting and Pearson correlation statistics analysis, the correlation between rheological (yield stress and yield stress change) and physicochemical parameters (VS/TS and dewaterability) were investigated. The results showed that all the goodness of fit (R²) were greater than 0.94. During the whole conventional anaerobic digestion, the yield stress was positively and strongly correlated with VS/TS value (R=0.975, P<0.01), and the yield stress change was negatively and strongly correlated with dewaterability (R=-0.989, P<0.01). During low temperature thermal hydrolysis anaerobic digestion, the yield stress was positively and strongly correlated with VS/TS value (R=0.990, P<0.01), and the yield stress change was negatively and strongly correlated with dewaterability improved (R=-0.992, P<0.01). It is implied that there is a strong correlation between sludge yield stress and sludge VS/TS value. From the perspective of rheology, it provided the new ideas and theoretical basis for monitoring and optimization in the process of anaerobic digestion. In this study, the theoretical basis and feasibility of rheological control indicators for evaluating and monitoring low temperature thermal hydrolysis and anaerobic digestion processes (performance) were provided. Finally, the future work should focus on investigating the specific effects of specific ingredients (including polysaccharides, proteins, lipids, humic acids, glycoproteins, etc.) in EPS on sludge dehydration, and exploring the different forms of water in the sludge during anaerobic digestion, to reveal the relationship between the change law and sludge rheology, and clarifying the mechanism of sludge rheology and dehydration performance during anaerobic digestion. At the same time, the research on the influence of rheology on the level of chemistry and microorganism also needs to make progress.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:48
Main heading:Anaerobic digestion
Controlled terms:Agricultural robots - Ammonia - Binary alloys - Biogas - Correlation methods - Dehydration - Elasticity - Hydrolysis - Indicators (chemical) - Physicochemical properties  - Renewable energy resources - Sludge digestion - Strontium alloys - Substrates - Temperature - Volatile fatty acids - Wastewater treatment - Yield stress
Uncontrolled terms:Anaerobic digestion process - Consistency coefficient - Dehydration performance - Interactive relationships - Physicochemical parameters - Renewable energy source - Rheological indicators - Thermal hydrolysis pretreatment
Classification code:452.2  Sewage Treatment - 452.4  Industrial Wastes Treatment and Disposal - 522  Gas Fuels - 525.1  Energy Resources and Renewable Energy Issues - 549.2  Alkaline Earth Metals - 641.1  Thermodynamics - 801  Chemistry - 802.2  Chemical Reactions - 804  Chemical Products Generally - 922.2  Mathematical Statistics - 951  Materials Science
Numerical data indexing:Age 5.48e-02yr, Mass_Density 1.00e-02kg/m3 to 1.30e-01kg/m3, Percentage 1.59e+00%, Percentage 4.46e+01%, Percentage 4.83e+01%, Percentage 6.45e+01%, Percentage 7.15e+01%, Percentage 9.09e+01%, Percentage 9.28e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.027

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 27>

Accession number:20202108693547
Title:Design and test of twin screw extruder for Lentinus edodes
Title of translation:&#39321;&#33735;&#21452;&#34746;&#26438;&#25380;&#21387;&#33192;&#21270;&#26426;&#30340;&#35774;&#35745;&#19982;&#35797;&#39564;
Authors:Wang, Mingyou (1); Song, Weidong (1); Ding, Tianhang (1); Wang, Jiaoling (1); Zhou, Dehuan (1); Wu, Jinji (1)
Author affiliation:(1) Nanjing Institute of Agricultural Mechanization, Ministry of Agriculture and Rural Affairs, Nanjing; 210014, China
Corresponding author:Song, Weidong(songwd@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:293-301
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China is the largest producer and exporter of Lentinus edodes in the world. To improve its market value, twin-screw extrusion and expansion machine has been developed to further process the Lentinus edodes. To resolve the problems of blockage, low prematurity and missing operation parameters of this machine in producing Lentinus edodes pufferent, we presented an improved twin-screw extrusion and expansion machine in this paper to lower puffer ability, improve water absorption and reduce its hardness. The equipment consists of a frame, a mixing device, a feeding device, a tempering device, a heating device, an extruding and bulking device and a rotary cutting device. It is equipped with a cooling system, a lubricating system, a transmission system, a control system and a pressure detection system. Design and determination of the anti-blocking device for the feed mixing device, the pre-maturing and tempering device, and the structural parameters of the twin screw were conducted. In order to investigate the influence of operation parameters on swelling performance of the product, the Box-benhnken combined test method was used to study the working parameters of the double screw extruder. The effects of screw speed, extrusion temperature and water content on the swelling rate, hardness, brittleness and water absorption of the expanded product were analyzed, and the determinants were optimized. The results showed that, based on the level of the significance, 1) factors affecting the expansion rate were ranked in material water content > expansion temperature > screw speed, 2) factors affecting hardness were ranked in material moisture content > screw speed > swelling temperature, 3) factors affecting brittleness were ranked in material moisture content > screw speed, 4) factors affecting water absorption were ranked in material moisture content > swelling temperature > screw speed. The optimal operating parameters were: screw speed 167.23 r/min, swelling temperature 151.68&#8451;, material moisture content 16.83%. Under these conditions, the swelling rate, hardness, brittleness and water absorption of the product were increased by 4.04%, 18.61 N, -8.46 mm/cm² and 313.86% respectively, compared to the traditional machine. Practical application of the optimized parameters revealed that the error between the optimized productivity and real productivity was less than 4%, with the maximum productivity being 165 kg/h. Compared with the existing equipment in the laboratory at School of Mechanical Engineering in Yangzhou University, the designed machine increased the swelling rate, brittleness, water adsorption and brittleness by 25.00%, 40.55% and 62.35% respectively, while reducing the hardness by 48.21%. Therefore, the design of this machine can provide relatively mature technical equipment for the development of mushroom swelling products.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Water absorption
Controlled terms:Brittleness - Cutting equipment - Extruders - Extrusion - Fracture mechanics - Hardness - Mixing - Moisture determination - Plasticity - Product design  - Productivity - Speed - Swelling - Tempering - Testing - Water content
Uncontrolled terms:Extrusion temperatures - Maximum productivity - Operating parameters - Structural parameter - Technical equipments - Transmission systems - Twin screw extruders - Twin screw extrusion
Classification code:537.1  Heat Treatment Processes - 802.3  Chemical Operations - 913.1  Production Engineering - 931.1  Mechanics - 944.2  Moisture Measurements - 951  Materials Science
Numerical data indexing:Mass_Flow_Rate 4.58e-02kg/s, Percentage 1.68e+01%, Percentage 2.50e+01%, Percentage 3.14e+02%, Percentage 4.00e+00%, Percentage 4.04e+00%, Percentage 4.05e+01%, Percentage 4.82e+01%, Percentage 6.24e+01%, Rotational_Speed 1.67e+02RPM, Force 1.86e+01N
DOI:10.11975/j.issn.1002-6819.2020.05.034

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 28>

Accession number:20202108694014
Title:Experimental study on molding technology for making seedling block based on maize stovers
Title of translation:&#29577;&#31859;&#31224;&#31174;&#32946;&#33495;&#31181;&#22376;&#25104;&#22411;&#24037;&#33402;&#35797;&#39564;&#30740;&#31350;
Authors:Liu, Dejun (1); Zhou, Yanji (1); Liu, Kun (1); Cheng, Qian (1); Bai, Xuewei (1); Gong, Yuanjuan (1)
Author affiliation:(1) Engineering College, Shenyang Agricultural University, Shenyang; 110866, China
Corresponding author:Gong, Yuanjuan(yuanjuangong@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:241-248
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Seedling blocks contained maize stovers as the main component, added cow manure, inorganic complex, polyacrylate sodium, ferrous sulfate, and other auxiliary materials ground as the substrate for growing seedlings, the seed once pressed molding in the substrate, also could be planted in the planting hole. First of all, the production process for making seedling block based on maize stovers were discussed in this study, regarded the crushed maize stovers mixed with cow dung as premixed materials, polyacrylate sodium and other supplementary material dissolved as premixed liquid to soak of strovers and cow dung, ground into a viscous paste together as matrix material, using homemade compression mold, hot pepper seeds and substrate material compressed into a block together, the final drying to facilitate storage and transportation. The matrix conductivity in the process of the test was no more than 800 &micro;s/cm, or else reduce the concentration of the pre-mixed solution to ensure the seed normal germination. The material characteristics of substrate and nutrition were tested or laboratory analyzed, the determination of substrate materials, pH value of 6.4 was suitable to the vegetation, the unit weight of 0.4 g/cm³, the total porosity of 65.82%, the aeration porosity of 19.16%, the water-holding porosity of 56.66%, in addition to the phosphorus and potassium levels slightly higher, nitrogen, iron, magnesium, and other nutritional elements were in suitable range. In this study, the pressed seedling block was put on the test platform of the WDW-200 compression testing machine, and the stress at the deformation degree of 20% was taken as the destructive strength. Soak the blocks water for more than 2 hours or spray for more than 3 hours, until the mass after absorption was no longer changed, with the mass after absorption minus the mass before absorption divided by the mass after absorption determined the water absorption. According to the test method of seedling block water absorption, the measurement of the expansion rate is the volume difference after and before water absorption divided by the volume without water absorption. By using the Design-Expert 8.06 software and according to the general rotating combination design method, the three-factors quadratic orthogonal rotating combination experiment was selected. The test results showed that the destructive strength of block was significantly higher when the water content was between 15.99% and 22.03% and decreased when it exceeded 30%. The larger compression ratio and the greater destructive strength of block led to the lower water absorption. When the compression ratio was 2.25, the maximum expansion rate was 4.60%, and then gradually decreased with the increase of the compression ratio to a minimum of 2.80%. The compression speed had a certain influence on the destructive strength of blocks, but it was not obvious. The influence on the water absorption conformed to the logarithmic function, and the influence on the expansion rate conformed to the quadratic function. The Orthogonal rotation combination test of the ternary quadratic was carried out to establish the mathematical model between the parameters of water content, compression ratio, compression speed, and water absorption, anti-destruction strength, and expansion rate. The optimized parameter of each index was obtained as follows: water content was 22%, the compression ratio was 2.9, and the compression speed was 90 mm/min. The results of the verification test showed that the seedling blocks met the requirements of seedling raising with good water absorption, destructive strength, and lower expansion rate. Seedling blocks compressed with hot pepper soaked for 2 hours and then micro-sprayed for 7 days, the germination rate reached 95%. The study provided a theoretical basis for the stovers seedling blocks molding process, the design, and optimization of molding machinery.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Water absorption
Controlled terms:Compression testing - Compressive strength - Cultivation - Fertilizers - Machine design - Machinery - Materials handling - Molding - Nutrition - Porosity  - Seed - Sodium compounds - Substrates - Sulfur compounds
Uncontrolled terms:Compression testing machines - Logarithmic functions - Material characteristics - Molding technologies - Nutritional elements - Orthogonal rotations - Polyacrylate sodium - Storage and transportations
Classification code:461.7  Health Care - 601  Mechanical Design - 802.3  Chemical Operations - 804  Chemical Products Generally - 821.3  Agricultural Methods - 821.4  Agricultural Products - 931.2  Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Percentage 4.60e+00%, Percentage 5.67e+01%, Percentage 6.58e+01%, Percentage 9.50e+01%, Time 1.08e+04s, Time 7.20e+03s, Age 1.92e-02yr, Mass_Density 4.00e+02kg/m3, Percentage 1.60e+01% to 2.20e+01%, Percentage 1.92e+01%, Percentage 2.00e+01%, Percentage 2.20e+01%, Percentage 2.80e+00%, Percentage 3.00e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.028

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 29>

Accession number:20202108693826
Title:Spatial pattern and influencing factors of labor transfer intensity of rural poverty-stricken families in southwest mountainous areas of China
Title of translation:&#35199;&#21335;&#23665;&#21306;&#26449;&#22495;&#36139;&#22256;&#23478;&#24237;&#21171;&#21160;&#21147;&#36716;&#31227;&#24378;&#24230;&#31354;&#38388;&#26684;&#23616;&#21450;&#24433;&#21709;&#22240;&#32032;
Authors:He, Tian (1); Liao, Heping (1, 2); Sun, Pingjun (1); Liu, Yuanli (1); Wang, Gang (1); Qing, Libo (3)
Author affiliation:(1) School of Geographical Science, Southwest University, Chongqing; 400715, China; (2) Southwest University Center for Targeted Poverty Alleviation and Regional Development Assessment, Chongqing; 400715, China; (3) Mian Yang High School, Mianyang; 621000, China
Corresponding author:Liao, Heping(liaohp@swu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:325-334
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Labor transfer is regarded as an crucial way to increase family income and ameliorate poverty for poverty-stricken families in mountainous areas in the southwest China. The negative consequence is that it causes labor loss, slowing or damaging local social-economic development. It is hence important to implement national strategies to alleviate poverty while in the meantime revitalizing local economy, in which understanding spatial pattern of the migration workers and the underlying factors plays a key role. Taking Changshou District at Chongqing as an example, this paper surveyed and analyzed migrating labors from poverty-stricken families in the villages using a comprehensive evaluation method. Using the geographic detecting model and the OLS regression model, we diagnosed the main factors underpinning the difference in labor transfer between the villages in these areas. The main results were: 1) There was a regional difference in labor transfer from poverty-stricken families between the villages, characterized by "two-highs and one-low", with the "two-highs" representing Mingyue Mountainous Area in the West and Huangcao Mountainous area in the Southeast and the "one-low" representing the southwest-central low hilly area. 2) The main factors underlying the difference in labor transfer from the poverty-stricken families between the villages were age, cultivable land per capita, land slope and labor training, and the distribution of the decisive power of these four factors was 0.410, 0.396, 0.363 and 0.301, respectively. 3) Labor transfer was a result of the interaction of multiple factors, and the interaction of any pair of factors was greater than that of any single factor. 4) Based on the factors underlying the difference in labor transfer from poverty-stricken families between the villages, we recommend that each village should take strategies based on its location, economy and society to orderly implement poverty-alleviation strategies and revitalize local economy so as to reduce labor transfer.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:41
Main heading:Rural areas
Controlled terms:Economic and social effects - Economics - Regression analysis
Uncontrolled terms:Comprehensive evaluation - Economy and society - Multiple factors - National strategies - Poverty alleviation - Regional differences - Spatial patterns - Underlying factors
Classification code:922.2  Mathematical Statistics - 971  Social Sciences
DOI:10.11975/j.issn.1002-6819.2020.05.038

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 30>

Accession number:20202108693658
Title:Optimization of sodium bisulfate catalyzed esterification of soapstock of coconut oil to deacidification
Title of translation:NaHSO<inf>4</inf>&#20652;&#21270;&#26928;&#23376;&#27833;&#30338;&#33050;&#27833;&#37231;&#21270;&#38477;&#37240;&#24037;&#33402;&#20248;&#21270;
Authors:Li, Huiwen (1); Yang, Lingmei (1); Miao, Changlin (1); L&uuml;, Pengmei (1); Wang, Zhongming (1); Yuan, Zhenhong (1)
Author affiliation:(1) Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Key Laboratory of Renewable Energy, Guangzhou; 510640, China
Corresponding author:Miao, Changlin(miaocl@ms.giec.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:255-260
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biodiesel is a fatty acid alkyl ester derived from renewable feedstocks such as plant oils, animal fats or waste oils by transesterification with short-chain alcohols and catalyst. It has attracted attention in the past decades as an alternative and sustainable energy source. The esterification efficiency of biodiesel using soapstock of coconut oil as raw material is related to catalyst and the operation method binding reaction device. Heterogeneous catalyst has the general advantages of easy separation, medium and reusability. In this paper, esterification of biodiesel with soapstock of coconut oil was studied using sodium bisulfate as catalyst on self-designed reaction device. First, the reaction conditions suitable for the device were studied through single factor experiments. Then, the effects of different operation modes on the reaction rate and process were researched. It indicated that proper operation method plays a key role in acid reduction of low grade oil. At the beginning, the results showed that the optimum conditions were as follows:When the reaction temperature was 105 &#8451;, the methanol flow rate was 0.825 mL/min, catalyst dosage was 5.0% and more than 95% esterification rate was obtained after 2 hours. Meanwhile, under this condition esterification rate was 78.15% after 9 times of catalyst reuse. The high stability can be recognized, which strengthen the target that to reduce the cost of produce through the reuse of catalyst. At last, esterification rate was 98.9%, and esterification time was shortened by 1 hour when changed the operation approaches by the amount of methanol was injected at 1.32 mL/min for 30 min under pressure condition, subsequently the amount of methanol was injected at 0.825 mL/min for 30 min under normal pressure condition. We are happy to see that the acid value of the coconut oil soap foot oil reduced from 106 to 1.2 mg/g using this operation method. This means that we have successfully reduced the acid value of high acid value oil and the oil met the requirements of the subsequent ester exchange process. The raw material of low acid oil can be transformed into biodiesel by transesterification and biodiesel was being tested technical indicators met the current German biodiesel standards (DIN V 51606) after transesterification.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Esters
Controlled terms:Biodiesel - Catalysts - Esterification - Fatty acids - Methanol - Reusability - Sodium compounds - Transesterification - Vegetable oils
Uncontrolled terms:Fatty acid alkyl esters - Heterogeneous catalyst - Pressure conditions - Reaction temperature - Renewable feedstocks - Short chain alcohols - Single-factor experiments - Sustainable energy sources
Classification code:523  Liquid Fuels - 802.2  Chemical Reactions - 803  Chemical Agents and Basic Industrial Chemicals - 804  Chemical Products Generally - 804.1  Organic Compounds
Numerical data indexing:Percentage 5.00e+00%, Percentage 7.82e+01%, Percentage 9.50e+01%, Percentage 9.89e+01%, Time 1.80e+03s, Time 3.60e+03s, Time 7.20e+03s
DOI:10.11975/j.issn.1002-6819.2020.05.030

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 31>

Accession number:20202108693640
Title:Effects of planting patterns and irrigation quotas on alkalized solonchak and growth of amorpha
Title of translation:&#31181;&#26893;&#26041;&#24335;&#21644;&#28748;&#28297;&#23450;&#39069;&#23545;&#30897;&#21270;&#30416;&#22303;&#21450;&#32043;&#31319;&#27088;&#29983;&#38271;&#30340;&#24433;&#21709;
Authors:Wang, Xu (1); Fan, Liqin (1); Li, Lei (1); Sun, Zhaojun (2, 3); El-Sway, Sameh (4)
Author affiliation:(1) Institute of Agricultural Resources and Environment, Ningxia Academy of Agriculture and Forestry Sciences, Yinchuan; 750002, China; (2) Institute of Environmental Engineering, Ningxia University, Yinchuan; 750021, China; (3) Ningxia (China-Arab) Key Laboratory of Resources Assessment and Environmental Regulation in Arid Regions, Yinchuan; 750021, China; (4) Vegetable Research Department, Agricultural and Biological Division, National Research Centre, Giza; 12311, Egypt
Corresponding author:Sun, Zhaojun(sunzhaojunyx@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:88-95
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Saline-alkali soil is a general name referring to saline soil, alkaline earth salt and other saline and solonetzic soils. Accumulation of soluble salts in the proximity of the surface of saline-alkali soil could result in salt stress impeding crop growth as a result. Soil salinity is a limiting factor in agricultural production and an environment concern not only in China but worldwide. Gansu province in Chinahas a type of alkalized solonchak, a special saline soil characterized by high salt contentand poor soil structure which combined to impend crop growth. The purpose of this paper is to experimentally investigate the impact of planting patterns and irrigation amounts on soil salinity and plant growth in the alkalized solonchak. The experiment was conducted at Jingyuan in Gansu province (37&deg;02' N, 104&deg;96' E) using amorpha (Amorpha fruticosa L.) grown in the alkalized solonchak as the model plant. Prior to the experiment, desulfurized gypsum was applied to the soil at 18 t/hm². We compared two planting pattern: furrow planting and non-furrow planting, and three irrigation amounts: 8 250, 9 750, 11 250 m³/hm², each treatment having three replicas. The results show that: 1) All treatments significantly reduced soil pH, alkalinity and salt content, and there was no significant difference in pH and alkalinity between the treatments. Saltcontent in top 0-40 cm soil under furrow planting decreased by 15.7% compared to that under non-furrow planting. 2) Under furrow planting, the irrigation and precipitation accumulated in the furrow ditch, thereby improving soil moisture and reducing soil salinity, compared that under non-furrow planting. Furrow planning improved survival rate, preservation rate, height, base diameter and crown width of the amorpha, compared to non-furrow planting. 3) There was no significant difference in growth index of the amorpha between the irrigation 9 750 and 11 250 m³/hm², indicting excessive irrigation not only wasted water but also increased the risk of secondary salinization. Using raised-bed cultivation with the amorpha planted in the furrow, along with applying 18 t/hm² of desulfurized gypsumand irrigating 9 750 m³/hm² of water was most suitable for improving plant growth in the alkalized solonchak in Gansu province. The results have wide application for developing sustainable agriculture inthe alkalized solonchak in Gansu and other regions.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Irrigation
Controlled terms:Agricultural robots - Alkalinity - Crops - Cultivation - pH - Soil moisture
Uncontrolled terms:Agricultural productions - Alkaline earth salts - Desulfurized gypsums - Irrigation amounts - Irrigation quotas - Saline-alkali soils - Soil structure - Sustainable agriculture
Classification code:483.1  Soils and Soil Mechanics - 801.1  Chemistry, General - 821.3  Agricultural Methods - 821.4  Agricultural Products
Numerical data indexing:Percentage 1.57e+01%, Size 0.00e+00m to 4.00e-01m
DOI:10.11975/j.issn.1002-6819.2020.05.010

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 32>

Accession number:20202108693662
Title:Comparison of droplet deposition characteristics and cotton aphid control effect of plant protection UAV working during the day and night
Title of translation:&#26893;&#20445;&#26080;&#20154;&#26426;&#26172;&#22812;&#20316;&#19994;&#30340;&#38654;&#28404;&#27785;&#31215;&#29305;&#24615;&#21450;&#26825;&#34460;&#38450;&#25928;&#23545;&#27604;
Authors:Tian, Zhiwei (1); Xue, Xinyu (1); Cui, Longfei (1); Chen, Chen (1); Peng, Bin (2); Liu, Bing (3)
Author affiliation:(1) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture and Rural Affairs, Nanjing; 210014, China; (2) Guangzhou Ji Fei Technology Co. Ltd., Guangzhou; 510663, China; (3) Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing; 100193, 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:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:69-77
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plant protection UAV is characterized by high efficiency, safe operation and strong applicability, it has developed rapidly in recent years and has become one of the main prevention and control methods for pests and diseases. However, there still has some problems during the process of controlling cotton aphids, such as the droplet deposition law in the target spray area is not clear, the operating parameters are set unreasonably, and the droplet deposition characteristics and control effect for night operations are unknown. To solve the problems mentioned above, the experiments were carried out at the Korla Test Base of the Institute of Plant Protection of the Chinese Academy of Agricultural Sciences in 2018 and 2019. P20 plant protection UAV was adopted with different operating parameters (at flight speed of 3, 4 and 5 m/s, flight height of 1.5, 2 and 2.5 m, spray volume of 7.5, 11.3 and 15 L/hm²) to spray pesticides during the day and night, and the boom sprayer and spray gun were used as control devices. The Latin hypercube method was used in test design and each treatment was repeated 3 times. The test results showed that there was a significant difference in the number of droplets between day and night operations. Under the same operating parameters, the number of droplets deposited at night was on average 42.82% higher than that during the day, and the coverage rate of droplets was increased by 51.04%. At the same time, the penetration of droplets was better at night, and the number of droplets deposited in the middle and lower layers of cotton plant and the back side of the leaves were more than that in daytime. During night operations, the average number of droplets deposited in the middle and lower layers of cotton plant accounted for 34.79% and 22.07% of the total number of droplets in the vertical direction, and averaged 33.27% and 21.89% during the day, and that of the spray guns were 29.50% and 19.98%, boom sprayer were 43.30% and 15.84%. The average number of droplets deposited on the leaves back of the night operation accounted for 19.80% of the total number of droplets deposited on the front and back side of leaf, and 14.18% in the daytime, and the propotion of the night was 39.63%, which was higher than that of the day. The number of droplets deposited on the back side of leaf of each sampling layer of plant was upper layer> lower layer> middle layer. In general, the proportion of droplets deposited on the leaf back did not exceed 25% for UAV operation. Droplets deposited on the leaf back was less for spraying by spray gun and boom sprayer operation, which accounting for 7.09% and 0.20%, respectively. During cotton flowering and bud stage, in order to increase the number of droplets deposited and the penetrability of the droplets, it is recommended to set the UAV operating parameters to a flight height of 1.5 to 2 m, a flight speed of 3 to 4 m / s, and a large spraying volume, because the rotor wind field can effectively promote the penetration of the droplets only if the drone does not weaken the wind field and the droplets are not lost. In terms of the relationship between the reduction rate of cotton aphids and the number of droplet deposited on the back side of the leaves, they are positively correlated with each other on 1st day after application, but no correlation on 10th day because natural enemies. The results also showed UAV application at night is more effective to control cotton aphid compared with application in daytime, and a 20% reduction on the pesticide dose had no significant effect on the control effect of cotton aphid. This research can provide reference for the reasonable operating parameters setting of plant protection UAV, and also provide a scientific basis for the effective prevention and control of cotton aphids.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Drops
Controlled terms:Agricultural robots - Aircraft control - Cotton - Deposition - Disease control - Pesticides - Plants (botany) - Spray guns - Unmanned aerial vehicles (UAV)
Uncontrolled terms:Agricultural science - Droplet deposition - Natural enemies - Operating parameters - Plant protection - Prevention and controls - Scientific basis - Vertical direction
Classification code:652  Aircraft and Avionics - 652.1  Aircraft, General - 802.3  Chemical Operations - 803  Chemical Agents and Basic Industrial Chemicals - 821.4  Agricultural Products
Numerical data indexing:Percentage 1.42e+01%, Percentage 1.58e+01%, Percentage 1.98e+01%, Percentage 2.00e+01%, Percentage 2.00e-01%, Percentage 2.19e+01%, Percentage 2.21e+01%, Percentage 2.50e+01%, Percentage 2.95e+01%, Percentage 3.33e+01%, Percentage 3.48e+01%, Percentage 3.96e+01%, Percentage 4.28e+01%, Percentage 4.33e+01%, Percentage 5.10e+01%, Percentage 7.09e+00%, Size 1.50e+00m to 2.00e+00m, Size 2.00e+00m, Size 2.50e+00m, Velocity 3.00e+00m/s to 4.00e+00m/s, Velocity 4.00e+00m/s, Velocity 5.00e+00m/s
DOI:10.11975/j.issn.1002-6819.2020.05.008

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 33>

Accession number:20202108693886
Title:Effects of vegetation structure types and rainfall patterns on soil and water loss of understory vegetation in red soil areas of South China
Title of translation:&#21335;&#26041;&#32418;&#22756;&#21306;&#26893;&#34987;&#32467;&#26500;&#31867;&#22411;&#19982;&#38477;&#38632;&#27169;&#24335;&#23545;&#26519;&#19979;&#27700;&#22303;&#27969;&#22833;&#30340;&#24433;&#21709;
Authors:Chen, Yang (1, 3); Zhang, Haidong (2); Yu, Dongsheng (1, 3); Ma, Lixia (1); Lu, Xiaosong (1, 3); Wang, Xin (1, 3)
Author affiliation:(1) State Key Laboratory of Soil and Agricultural Sustainable Development, Nanjing Soil Research Institute, Chinese Academy of Sciences, Nanjing; 210008, China; (2) Suzhou Academy of Agricultural Sciences (Taihu Region Research Institute of Agricultural Science), Suzhou; 215155, China; (3) University of Chinese Academy of Sciences, Beijing; 100049, China
Corresponding author:Yu, Dongsheng(dshyu@issas.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:150-157
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Vegetation and rainfall are the key factors that affect the soil and soil erosion. Exploring the surface runoff and soil loss process associated with different rainfall patterns and vegetation structure types is of great significance to the development of soil and water conservation. In this study, we carried out a series of experiments on surface runoffs and sediments monitoring at different runoff plots with five structures types of vegetation (i.e., shrub-grass mixed forest, grassland, low shrub, arbor forest, high shrub). There are 8 runoff test plots with length &times; width (10 m&times;2.6 m) on the gentle slope of 8&deg;in Red soil Ecological Experimental Station, Yingtan city. The experiment lasted three years from 2016 to 2018. During the study period, 93 individual natural erosive rainfall events, surface runoffs and sediments data were collected, as well as the vegetation structure parameters were obtained. The self-organizing mapping (SOM) method was applied to classify rainfall patterns according to rainfall characteristic indicators such as rainfall amounts, rainfall durations, 60min maximum rainfall intensity, average rainfall intensity and rainfall amount concentration index. Then the characteristics of soil and water loss under different rainfall patterns and vegetation structure types were studied, and the effect of rainfall and vegetation on soil and water loss were quantitative analysis by redundancy analysis (RDA). The results showed that SOM method could identify the four typical erosion rainfall patterns in red soil region, the rainfall patterns were as follows: R<inf>I</inf> (low intensity, long duration, minor amount of rainfall and low rainfall concentration index), R<inf>II</inf> (medium amount of rainfall, moderate intensity and long duration), R<inf>III</inf> (short duration, strong rainfall intensity and high rainfall concentration index), R<inf>IV</inf> (a great amount of rainfall, strong rainfall intensity and long duration). Among all of the erosion rainfall events, the least rainfall was pattern R<inf>IV</inf>, which was the most erosive and destructive, so it was easy to cause serious soil erosion. R<inf>III</inf> was the main pattern that made the highest cumulative contribution rate to soil and water loss. The erosion ability of pattern R<inf>II</inf> was moderate, but it was also easy to cause soil and water loss due to its moderate intensity and long duration. The pattern R<inf>I</inf> could hardly cause soil erosion. Vegetation structure types significantly affected the soil erosion and runoff generation, and the soil and water conservation function of different vegetation in turn was as followed the order of shrub-grass mixed forest, grassland, low shrub, arbor forest, and high shrub. RDA results shown that comprehensive interaction effects on soil erosion exist between rainfall patterns and vegetation structure types. The ability of soil and water conservation of vegetation decreased gradually and the effects of rainfall became greater in the later stage of erosion process, when rainfall patterns changed from weak to strong (R<inf>I</inf>&rarr;R<inf>II</inf>&rarr;R<inf>III</inf>&rarr;R<inf>IV</inf>), meanwhile the dominant factors of soil and water loss changed from vegetation to the interaction of vegetation and precipitation, and then to rainfalls. The influences of canopy structure on soil and water loss reduced, while the ones of rainfall increased when vegetation structure types changed from near surface vegetation to shrub and tree.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:38
Main heading:Rain
Controlled terms:Erosion - Forestry - Runoff - Self organizing maps - Soil conservation - Soils - Vegetation - Water conservation
Uncontrolled terms:Effects of rainfalls - Experimental stations - Rainfall characteristics - Rainfall concentration - Redundancy analysis (RDA) - Self-organizing mapping - Soil and water conservation - Understory vegetation
Classification code:443.3  Precipitation - 444  Water Resources - 444.1  Surface Water - 483.1  Soils and Soil Mechanics
Numerical data indexing:Time 3.60e+03s
DOI:10.11975/j.issn.1002-6819.2020.05.017

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 34>

Accession number:20202108693659
Title:Analysis of direct injection combustion characteristics of hydrous ethanol gasoline based on optical single cylinder engine
Title of translation:&#22522;&#20110;&#20809;&#23398;&#21333;&#32568;&#26426;&#30340;&#21547;&#27700;&#20057;&#37255;&#27773;&#27833;&#30452;&#21943;&#29123;&#28903;&#29305;&#24615;&#20998;&#26512;
Authors:Shi, Xiuyong (1); Duan, Yifei (1); Ma, Xiao (2); Zhang, Zhou (2); Kang, Yang (1); Liao, Yansu (1); Ni, Jimin (1)
Author affiliation:(1) School of Automotive Studies, Tongji University, Shanghai; 201804, China; (2) State Key Laboratory of Automotive Energy Conservation and Safety, Tsinghua University, Beijing; 100084, China
Corresponding author:Ma, Xiao(max@tsinghua.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:59-68
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, gasoline direct injection (GDI) engines have been promoted worldwide by virtue of its advantages of economy and efficiency, but their particulate emissions are increased significantly compared to port fuel injection (PFI) engines. Ethanol has good research prospects due to its advantages such as high-octane number, low pollution and renewability. At the same time, ethanol has a certain effect on reducing particulate emissions from the engine. The existing research on the application of aqueous ethanol gasoline in GDI engine mainly focuses on the combustion and emission characteristics based on macroscopic characteristics, and there are few microscopic analysis of the flame development and soot formation. On basis of this, this paper studied the cylinder pressure, heat release rate and combustion phase of E10W (10% hydrous ethanol by volume ratio), E20W (20% hydrous ethanol by volume ratio) and E100W (pure hydrous ethanol) under different fuel injection strategies by optical single cylinder engine test, and analyzed the flame development and soot formation characteristics of the combustion process of hydrous ethanol gasoline. It was found that under the normal fuel injection strategy (start of injection, SOI=-280&deg;CA), the peak value of cylinder pressure and heat release rate gradually increased with the increase of the proportion of hydrous ethanol, the cylinder pressure peak value of E100W increases by 10% compared to E10W, while the heat release rate did not increase significantly. The combustion phase angle advanced by 2&deg;CA, the flame propagation speed increased by 15% and the combustion duration was shortened. The combustion coefficient of variation of E100W was 20% lower than that of the E10W and E20W. After delaying fuel injection (SOI=-90&deg;CA), the change of the proportion of hydrous ethanol had no obvious effect on the combustion characteristics. The cylinder pressure peak value of E100W increased by 5%, the combustion phase was significantly advanced compared with the normal injection, and the combustion coefficient of variation increased to twice as much. The flame development characteristics showed that the flame brightness reached the maximum after the flame filled in the combustion chamber, and the flame front was biased toward the rich side of the mixture, which was consistent with the pool fire burning area on the wall. There were more yellow brown flames in the intense pool fire area, and the soot production was higher. Increasing the mixing ratio of the hydrous ethanol could accelerate the flame development speed. The time when E100W flame filled the combustion chamber was 3 &deg; CA ahead that of E10W and E20W, and the flame brightness increased. At the same time, after the fuel injection was delayed, the flame partitioning phenomenon in the cylinder was obvious, the uneven combustion phenomenon was intensified, and the combustion in the oil film pool was increased obviously. The addition of hydrous ethanol can improve the combustion characteristics, make the flame spread more uniform, reduce the area of pool fire burning intensely, and the relative content of soot can be reduced by 90%. Therefore, using a mixture of hydrous ethanol and gasoline as the fuel of GDI engines can effectively improve the combustion characteristics of the engine, accelerate the flame propagation speed and reduce the amount of soot, and have a better effect on improving the performance of GDI engines and reduce PM emissions.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Combustion
Controlled terms:Combustion chambers - Direct injection - Dust - Engine cylinders - Ethanol - Fuel economy - Gasoline - Lakes - Luminance - Mixtures  - Particles (particulate matter) - Particulate emissions - Petroleum prospecting - Soot - Supersonic aerodynamics
Uncontrolled terms:Coefficient of variation - Combustion characteristics - Direct-injection combustion - Emission characteristics - Flame propagation speed - Fuel injection strategies - Gasoline direct injection engines - Port fuel injection engines
Classification code:451.1  Air Pollution Sources - 512.1.2  Petroleum Deposits : Development Operations - 521  Fuel Combustion and Flame Research - 523  Liquid Fuels - 525.2  Energy Conservation - 612.1.1  Internal Combustion Engine Components - 651.1  Aerodynamics, General - 654.2  Rocket Engines - 804  Chemical Products Generally - 804.1  Organic Compounds - 951  Materials Science
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.50e+01%, Percentage 2.00e+01%, Percentage 5.00e+00%, Percentage 9.00e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.007

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 35>

Accession number:20202108693614
Title:Review on agricultural products smart traceability system affected by new generation information technology
Title of translation:&#26032;&#19968;&#20195;&#20449;&#24687;&#25216;&#26415;&#23545;&#20892;&#20135;&#21697;&#36861;&#28335;&#31995;&#32479;&#26234;&#33021;&#21270;&#24433;&#21709;&#30340;&#32508;&#36848;
Authors:Qian, Jianping (1); Wu, Wenbin (1); Yang, Peng (1)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Key Laboratory of Agricultural Remote Sensing, Beijing; 100081, China
Corresponding author:Yang, Peng(yangpeng@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:182-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:From the problem of mad cow disease to date, the traceability system as effective means to ensure food safety has been introduced for nearly 30 years. Now, reducing breakage degree for traceability chain, enhancing traceability credibility, and improving early warning capacity for agri-food quality and safety, these has increasingly become hot topics of traceability system research, which is also urgent problems in traceability system application. Focusing on these issues, the agricultural products smart traceability system affected by new generation information technologies based on the relevant literature was summarized and analyzed. Firstly, the development stages of traceability system from 1.0 to 3.0 were presented. The features of the three stages were information recording for 1.0, data integration for 2.0, and intelligent decision-making for 3.0, respectively. Secondly, the relationship of new generation information technology including internet of things (IoT), big data, cloud computing, blockchain, artificial intelligence (AI) was described. The new generation of information technology is not only the vertical promotion of single technology, but also the horizontal penetration of technology integration. The development trend about big data, artificial intelligence and block chain were summarized. Finally, the relevant research on the issues of reducing the breakage degree for traceability with AI, improving early warning capability for agri-food quality and safety with big data, and enhancing the traceability credibility of the whole supply chain with blockchain were summarized. The orientation of in-depth study was put forward in the light of the technology development trend. For combing AI, traceability granularity should be improved from within and among supply chains through establishment some flexible and intelligent traceability models. For coming big data, prediction quality and optimization processing model should be enhanced through data mining and analysis from different levels. For coming blockchain, traceability block structure optimization, privacy protection, block chain consensus algorithm should be performed to meet the requirement agri-food. In fact, AI, big data, block chain and other technologies have different characteristics. In order to improve the intelligent level for traceability system, the different technologies should be integrated deeply. This paper provides a useful reference for grasping the development trend of traceability system, for knowing the research hot spot and for understanding the application bottleneck.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:87
Main heading:Artificial intelligence
Controlled terms:Agricultural products - Agricultural robots - Big data - Blockchain - Data integration - Data mining - Data privacy - Decision making - Food safety - Internet of things  - Structural optimization - Supply chains
Uncontrolled terms:Consensus algorithms - Food quality and safeties - Information recording - Intelligent decision making - Internet of Things (IOT) - Technology development - Technology Integration - Traceability systems
Classification code:461.6  Medicine and Pharmacology - 723  Computer Software, Data Handling and Applications - 821.4  Agricultural Products - 912  Industrial Engineering and Management - 912.2  Management - 913  Production Planning and Control; Manufacturing - 921.5  Optimization Techniques
Numerical data indexing:Age 3.00e+01yr
DOI:10.11975/j.issn.1002-6819.2020.05.021

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 36>

Accession number:20202108693906
Title:Matching model and experiment of net working time utilization rate of seeder unit with plot length and area
Title of translation:&#25773;&#31181;&#26426;&#32452;&#32431;&#20316;&#19994;&#26102;&#38388;&#21033;&#29992;&#29575;&#19982;&#22320;&#22359;&#26465;&#20214;&#30340;&#21305;&#37197;&#27169;&#22411;&#19982;&#35797;&#39564;
Authors:Qiao, Jinyou (1); Shao, Guanghui (1); Li, Rong (1); Chen, Haitao (1); Wang, Wenfu (2); Li, Wenhua (3); Zhu, Shengjie (1); Liu, Teng (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin; 150030, China; (2) Heilongjiang Longmen Farm, Bei'an; 164000, China; (3) Heilongjiang Academy of Agricultural Sciences, Harbin; 150086, China
Corresponding author:Li, Wenhua(nkylwh@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:19-28
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The mechanized seeding operation is an important part in modern agricultural production, and the net operating time utilization rate of the seeder is an important indicator to impact the efficiency of seeder unit. According to machinery unit application principle, the new term of seasonal net time utilization rate was determined in this paper, each consumed time items of seeder unit was distinguished and relevant mathematic models were established based on mechanized seeding practice and sufficient survey, such as net operating time, turning time and time of adding fertilizer and seeds and so on. Based on this, three mathematical models of net operating time utilization rate of seeding machinery units were established according to different adding fertilizer and seed ways. The experiment scheme was designed, which uses the method of multi-point synchronous tracking measurement to test the time items in the seeding process without disturbing the normal seeding process. Data of each time items of 4 typical seeding machinery units were obtained during the experiments. The statistic principle of 3&sigma; was used to distinguish and eliminate invalid experiment data. Based on the models established and effective tested data, Matlab 2012b was used to analysis the net operating time utilization rate of the 4 seeding machinery units changing with plot length and area under 3 different ways to add fertilizer and seed, the test results were expressed using Sigmaplot 12.5 software, and th quantitative correspondence between the different typical seeding machinery units and suitable operating plot area and length under the aimed net operating time utilization rate were determined. The results showed that when the aimed net operating time utilization rate of seeding machinery units is greater than 0.6, the John Deere 7 830 unit is suitable for the plots with areas no less than 6 hm² and the plot length is 1 200-1 400 m. The Valtra 171 unit is suitable for the plots with area no less than 6 hm² and the plot length is 1 000-1 200 m. The suitable plots for Changfa 504 unit are that area is no less than 1 hm² and the plot length is 500-1 500 m. The plots with area no less than 0.3 hm² and the plot length is 200-1 500 m are suitable for Huanghai 254 unit. The results can provide scientific accordance to select seeding machinery units for different plots.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Seed
Controlled terms:Agricultural robots - Fertilizers - Machinery - MATLAB - Software testing
Uncontrolled terms:Agricultural productions - Experiment data - Matching models - Mathematic model - Operating time - Quantitative correspondence - Seeding process - Utilization rates
Classification code:723.5  Computer Applications - 804  Chemical Products Generally - 821.4  Agricultural Products
Numerical data indexing:Size 1.00e+03m to 1.20e+03m, Size 1.20e+03m to 1.40e+03m, Size 2.00e+02m to 1.50e+03m, Size 5.00e+02m to 1.50e+03m
DOI:10.11975/j.issn.1002-6819.2020.05.003

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 37>

Accession number:20202108693813
Title:Monitoring and simulation of rainfall-runoff reduction effects and process on green roofs
Title of translation:&#32511;&#33394;&#23627;&#39030;&#38477;&#38632;&#24452;&#27969;&#21066;&#20943;&#25928;&#26524;&#30417;&#27979;&#19982;&#36807;&#31243;&#27169;&#25311;
Authors:Shen, Hongbin (1, 2); Xu, Zongxue (2); Zhang, Shuhan (3); Yin, Ruixue (3)
Author affiliation:(1) North China University of Water Resources and Electric Power, Henan Engineering Research Center of Hydraulic and Waterway, Zhengzhou; 450045, China; (2) College of Water Sciences, Beijing Normal University, Beijing Key Laboratory of Urban Hydrological Cycle and Sponge City Technology, Beijing; 100875, China; (3) Beijing Water Science and Technology Institute, Beijing Engineering Research Center for Non-Conventional Water Resources Utilization and Water Saving, Beijing; 100048, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:175-181
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Green roof is an important facility to mitigate urban flood resulted by increasing urbanization and impermeable surface. A thick substrate material layer with plants, grass, and/or trees, and extra structural support is one of main components of green roof. Due to the complexity of rainwater storage mechanism in the substrate material layer, the simulations results on rainfall-runoff on green roof are mostly unsatisfactory. In this study, the runoff reduction effect of green roof was simulated by considering the effect of substrate material layer on runoff. The green roof was compared with slope roof, plane roof and retention roof in order to understand the effect of substrate material layer on runoff. The experiment was carried out in Beijing Water Science and Technology Institute, China. The precipitation was measured by using a self-recording tipping bucket rain gauge. Runoff was monitored by using an equipment including water level gauges and triangular weir. The runoff coefficient and rainwater retention rate were calculated. A total of 11 rainfall-runoff events were monitored in 2015. The results showed that the change of the runoff coefficient was highly complex and it was influenced by many factors, e.g., precipitation, average/maximum rainfall intensity, and interval time between rainfall events. For all the monitored rainfall events, the average runoff coefficient values for plane roof, slope roof, green roof and retention roof were 0.68, 0.84, 0.41 and 0.43, respectively. The average rainwater retention rate values of green roof and retention roof were 58.9% and 57.2%, respectively. It indicated that the runoff reduction effects of green roof and retention roof are similar but both were better than the other two types of roofs. The runoff process of green roof was also similar with that of retention roof under the same rainfall conditions. Both the outflow processes from green roof and retention roof could be regarded as an unsteady orifice flow under the effect of accumulated water head on the roof-top. Thus, a unit hydrograph model to simulate runoff from green roof was proposed based on the saturated infiltration theory that included the thickness limitation of the substrate material layer and the influence of water accumulated on the surface. By using the proposed unit hydrograph model, the rainfall-runoff processes on green roof were simulated. The simulation results showed that the trends of the simulated and measured runoff were consistent well. The coefficient of determination and Nash-Sutcliffe efficiency were 0.85 and 0.84, respectively. This study will be helpful for further understanding the runoff reduction effect and the outflow mechanism of green roofs.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Roofs
Controlled terms:Rain - Rain gages - Runoff - Water levels
Uncontrolled terms:Coefficient of determination - Impermeable surface - Rainfall condition - Rainfall-runoff events - Rainfall-runoff process - Runoff coefficients - Substrate material - Tipping bucket rain gauge
Classification code:442.1  Flood Control - 443.2  Meteorological Instrumentation - 443.3  Precipitation
Numerical data indexing:Percentage 5.72e+01%, Percentage 5.89e+01%
DOI:10.11975/j.issn.1002-6819.2020.05.020

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.

<RECORD 38>

Accession number:20202108693846
Title:Simulation analysis and test on the filling performance of rotary type-hole precision seed-metering device for cotton
Title of translation:&#36716;&#36724;&#22411;&#23380;&#24335;&#31934;&#37327;&#25490;&#31181;&#22120;&#20805;&#31181;&#24615;&#33021;&#20223;&#30495;&#20998;&#26512;&#19982;&#35797;&#39564;
Authors:Li, Juanjuan (1); Zhang, Heping (2); Bi, Xinsheng (1); Wang, Jian (1); Hu, Bin (1); Li, Shuzhuo (1)
Author affiliation:(1) College of Mechanical Electrical Engineering, Shihezi University, Shihezi; 832000, China; (2) Xinjiang Kenong Machinery Manufacturing Co. Ltd., Kuitun; 833200, China
Corresponding author:Bi, Xinsheng(bxs_mac@shzu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:36
Issue:5
Issue date:March 1, 2020
Publication year:2020
Pages:38-49
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Mechanical precision seed metering device is widely used in precision seeding technology because of its simple structure and uniform seed metering. Seed filling process is the key link of the whole operation process of seed metering device. The precision metering device is mainly divided into internal filling, side filling, external filling, and the combination of side filling and external filling according to the seed filling mode. In the operation process, the internal filling mode mainly completes the seeding operation through the process of type-hole filling and gravity clearing, and the seed motion parameters close to the type-hole directly affect the seeding quality of the machine. The rotary type-hole cotton precision seed metering device is a kind of mechanical precision seed metering device. In order to solve the problem of missing seed in the process of filling, the influence of the motion parameters of rotary type-hole cotton precision seed metering device on the filling performance by establishing the kinematic model of the seed filling process in this paper. Using the discrete element simulation software to analyze the speed change trend of cotton seed falling into the type-hole and the influence of seed wheel vibration frequency on seed group disturbance. Taking the vibration frequency of seed wheel, vibration offset angle of seed wheel and rotating speed of metering device as the test factors, and taking the qualified rate of seed spacing, replaying rate and missing rate as the test indexes, three factors and five levels of positive traffic rotation combined test are carried out to explore the influence of each factor on seed metering performance. Design expert 8.0.6 software is used to analyze the test results and optimize the regression model. Single factor simulation test results show that the instantaneous speed of cotton seed increases with the increase of the rotating speed of the seed wheel, the instantaneous speed of the cotton seed is less than that of the seed wheel when it is filled into the type-hole, the cotton seeds with lower relative speed have better filling effect. When the vibration frequency of the seed wheel is 7 Hz, the average value of the normal force of the seed group is the smallest, which is 0.75 N, at this time, the internal friction of the seed goup is the smallest, the cotton seed is easy to be taken by the type-hole, and the seed filling performance of the seed metering device is improved. The simulation results of quadratic regression general rotation combination show that when the rotating speed of the seed metering device is 12.59 r/min, the vibration offset angle of seed wheel is 8.06&deg; and the vibration frequency of seed wheel is 6.08 Hz, the qualified rate of seed spacing reaches the maximum of 94.5%, and the leak seeding rate is 2.9%, the repaly rate is 3.3%. On this basis, the platform validation test was carried out with Xinluzao No.61 cotton seed as the test object. The test results showed thatwhen the rotating speed of the seed metering device was 12 r/min, the maximum qualified rate of the seed spacing was 94.65%, the error between the rotating speed of the seed metering device and the simulation test is 5.4%, which verifies the accuracy of the simulation results. This study can provide a reference for the structural optimization of the key components of the rotary type-hole cotton precision metering device.<br/> &copy; 2020, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Vibration analysis
Controlled terms:Cotton - Filling - Kinematics - Pneumatic materials handling equipment - Regression analysis - Rotating machinery - Software testing - Speed - Structural optimization - Testing  - Wheels
Uncontrolled terms:Discrete element simulation - Instantaneous speed - Mechanical precision - Precision seed-metering devices - Quadratic regression - Seed metering devices - Simulation analysis - Vibration frequency
Classification code:601.1  Mechanical Devices - 601.2  Machine Components - 691.1  Materials Handling Equipment - 691.2  Materials Handling Methods - 723.5  Computer Applications - 821.4  Agricultural Products - 921.5  Optimization Techniques - 922.2  Mathematical Statistics - 931.1  Mechanics
Numerical data indexing:Force 7.50e-01N, Frequency 6.08e+00Hz, Frequency 7.00e+00Hz, Percentage 2.90e+00%, Percentage 3.30e+00%, Percentage 5.40e+00%, Percentage 9.45e+01%, Percentage 9.47e+01%, Rotational_Speed 1.20e+01RPM, Rotational_Speed 1.26e+01RPM
DOI:10.11975/j.issn.1002-6819.2020.05.005

Database:Compendex
Compilation and indexing terms, Copyright 2021 Elsevier Inc.