<RECORD 1>
Accession number:20182405313566
Title:Mechanical properties and stress strain model for bulk wheat based on stress path test
Authors:Jiang, Minmin (1, 2); Chen, Guixiang (1, 2)
Author affiliation:(1) School of Civil Engineering and Architecture, Henan University of Technology, Zhengzhou; 450001, China; (2) National Engineering Laboratory for Grain Storage and Transportation, Zhengzhou; 450001, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:280-287
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Total amount of stored grain in China is about 200 million tons, which is of great importance to ensure the quality and safety of grain during storage period, and to modernization of agriculture engineering. When a storage cycle is ended, grain will be discharged from bins, and then loaded in for another storage cycle. Vertical stress increases in loading process, while decreases in discharging process, and different stress path will be generated in the bulk grain, resulting in complicated pressure and frictional force on bin wall, which will cause crack, failure or even overturn of bin structures. It is vital to study stress strain relation and strength properties of bulk grain under different stress paths. Geotechnical constitutive models have been used in grain bin simulation, however, the feasibility of these models for bulk grain has not been validated. In this study, stress path triaxial test was utilized to simulate complicated load path in grain bins. Wheat purchased from grain depot in Zhengzhou City, Henan Province was used in this study. Specimen had water content of 10.9%, bulk density of 0.85 g/cm<sup>3</sup>, diameter of 61.8 mm and height of 125 mm, the average axial length of wheat kernel was 4.5 mm, and the ratio of specimen diameter to kernel axial length was 13.7, which was larger than the minimum specified ratio for triaxial test. Three types of stress paths were investigated in this study: conventional triaxial compression (CTC), constant mean normal stress compression (CMS), and reduced triaxial compression (RTC). In CTC test, radial stress was set as constant, while axial stress increased simultaneously; in CMS test, radial stress decreased, while axial stress increased simultaneously to keep mean normal stress constant; in RTC test, axial stress was set as constant, and radial stress decreased simultaneously. Stress path triaxial test procedure was as follows: After bulk wheat specimen was mounted on triaxial apparatus, isotropic stress was applied from 0 to prescribed value (50, 100, 150, 200, 250, 300 kPa); then CTC, CMS or RTC stress path was applied on specimen, and stress strain result was recorded until axial strain reached 30%. Initial modulus, secant modulus and critical state properties were determined from stress strain curve, strength and stress strain parameters were determined, and finally new model was proposed to depict stress strain relation for bulk wheat under different stress paths. Test results show that, under the same radial stress, CTC test has the largest initial modulus, and RTC test has the lowest value. Under all stress paths, initial modulus and secant modulus are found to be in a power function growth with the ascent of radial stress. In CTC test and CMS test, secant modulus is significantly lower than initial modulus; while in RTC test, secant modulus is not significantly reduced compared with initial modulus. Under reference pressure (atmospheric pressure), CTC test has the largest initial modulus of 24.1 MPa, and RTC test has the lowest value of 7.9 MPa; while initial modulus of RTC test has the largest increasing rate, CTC test has the lowest increasing rate. Under reference pressure, CTC test has the lowest secant modulus of 7.7 MPa, and RTC test has the largest value of 9 MPa; secant modulus of RTC test has the largest increasing rate, and CTC test has the lowest increasing rate. Deviator stress increased during shearing process, and specimen failed at the peak point on q-p (deviator stress - mean normal stress) plane. Under all stress path and radial stress situations, failure point fell on the same critical state line. Critical state line for bulk wheat has straight line form, and critical state stress ratio is 0.976. New modified cubic curve model for bulk wheat grain under different stress path conditions was proposed. In the model, strength conforms to Mohr-Coulomb failure criterion; crest reduction coefficient has linear relation with residual strength ratio; peak axial strain has linear relation with radial stress. Model parameters comprised apparent cohesion, internal friction angle, residual apparent cohesion, residual internal friction angle, parameter a and k for crest reduction coefficient, and parameter b and m for peak axial strain. Calculated results show that the proposed model can simulate the results of all stress paths under different confining stress levels. The model can reflect strain softening and strain hardening properties of bulk wheat; peak shear strength and residual shear strength can be determined; and the simulated stress and strain curve coincide well with the test results. The result of this paper provides more accurate parameters for grain bin load calculation considering the stress path conditions, and the new model can be used to estimate stress and deformation of bulk wheat, and to improve the designing method of grain bins.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:39
Main heading:Stress-strain curves
Controlled terms:Atmospheric pressure - Constitutive models - Critical current density (superconductivity) - Grain (agricultural product) - Internal friction - Models - Outages - Strain - Strain hardening - Stresses
Uncontrolled terms:Agriculture engineering - Bulk wheat - Conventional triaxial compression - Internal friction angle - Mohr-Coulomb failure criterion - Residual shear strength - Stress and deformation - Stress paths
Classification code:443.1 Atmospheric Properties - 537.1 Heat Treatment Processes - 701.1 Electricity: Basic Concepts and Phenomena - 706.1 Electric Power Systems - 821.4 Agricultural Products - 921 Mathematics - 951 Materials Science
Numerical data indexing:Mass_Density 8.50e+02kg/m3, Percentage 1.09e+01%, Percentage 3.00e+01%, Pressure 2.41e+07Pa, Pressure 3.00e+05Pa, Pressure 7.70e+06Pa, Size 1.25e-01m, Size 4.50e-03m, Size 6.18e-02m
DOI:10.11975/j.issn.1002-6819.2018.07.036
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 2>
Accession number:20182405313532
Title:Design and experiment of seedling avoidable weeding control device for intertillage maize (Zea Mays L.)
Authors:Jia, Honglei (1, 2); Li, Sensen (1, 2); Wang, Gang (1, 3); Liu, Huili (1)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun; 130022, China; (2) Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun; 130022, China; (3) College of Electronic Science & Engineering, Jilin University, Changchun; 130012, China
Corresponding author:Wang, Gang(gw1988@jlu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:15-22
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The organic farming requires reducing the application of chemical fertilizer and herbicide, and the weeds play a critical role in confronting the world food security which requires high yield crops. In order to solve the problem mentioned above, the mechanical weeding control device is being highlighted nowadays. In terms of the mechanical weeding components, there are finger weeding device, torsion weeding device, brush weeding device with vertical axis, spring tine harrow, and so on. Separating the crop seedlings and the weeds is the key procedure during the weeding control process, and the spectrum, and spectrum pictures, as well as the machine vision are major technologies, but one thing should be mentioned that these sensors are relatively expensive and robotic weeding device equipped with these sensors seldom can be found in agricultural field yet. Thus based on the design concept of not relying on the intelligent guide platform or agricultural robot, this manuscript developed a mechanical weeding device equipped with a flexible shaft, a travel switch, a stepper motor, an MCU (microcontroller unit), 3 brush plates, and so on. This device was designed to serve the inter-tillage maize (Zea Mays L.) field, owing to that the maize plants in this growing period are high and vigorous enough to block the flexible shaft so as to turn on the travel switch. According to the division of maize breeding period, the maize plant at that time was in the stage of elongation, at which the male ear was elongated, the total length of the base stem node should be between 2 and 3 cm, and the leaf age index was about 30. In normal working status, one of the 3 brush plates is perpendicular to the moving direction, the bottom of the brush teeth will stab into the soil so as to pull the weeds out, and the device moves along with the tractor equipment. If there is a connection between the maize stalk and the flexible shaft, the flexible shaft will bend, and thus the travel switch will be turned on. Subsequently, the stepper motor will start working and the brush plate which would damage the maize stalk will rotate by 120° anticlockwise, so as to avoid the nearest maize stalk. If the forward speed of the device and the rotation speed of the brushes don't match, maize seedlings will be damaged, and thus a program was written in the MCU to achieve an appropriate relationship between the forward speed and the rotation speed. The software SPSS 22.0 was applied to conduct an orthogonal test, the soil bin laboratory in Jilin University provided the essential equipment, and the test indices were seedling damage rate and weed removal rate, and the test factors were seedling distances (17, 20, 23, and 26 cm), forward speeds (3, 4, 5, and 6 km/h), as well as the stabbing depths of the brush teeth (5, 10, 15 and 20 mm). There was no interaction between any 2 test factors, and 16 experiments were conducted. The maize plants and green bristlegrass (Setaria viridis (L.) Beauv.) were transplanted into the soil bin. The experimental results showed that under the most optimized test levels, the average seedling damage rate was 5.9%, and the average weed removal rate was 94.7%. The ANOVA (analysis of variance) results showed the seedling distance had significant (P<0.05) influence on seedling damage rate, and the brush stabbing depth had significant (P<0.05) influence on both seedling damage rate and weed removal rate, but the forward speed didn't have significant (P>0.05) influence on either seedling damage rate or weed removal rate. This device can meet the requirement of intra-row weeding control in maize field, and it is easy to manufacture and cost-effective, and thus it can become a reference for farming mechanical weeding device.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Grain (agricultural product)
Controlled terms:Agricultural machinery - Controllers - Cost effectiveness - Crops - Design - Experiments - Fertilizers - Food supply - Intelligent robots - Machine design - Microcontrollers - Software testing - Soils - Speed - Stepping motors - Weed control
Uncontrolled terms:ANOVA (analysis of variance) - Chemical fertilizers - Damage rate - Essential equipments - Maize (Zea mays L.) - Microcontroller unit - Removal rate - Weed removal brush teeth
Classification code:483.1 Soils and Soil Mechanics - 601 Mechanical Design - 705.3 Electric Motors - 723.5 Computer Applications - 731.6 Robot Applications - 732.1 Control Equipment - 804 Chemical Products Generally - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 822.3 Food Products - 901.3 Engineering Research - 911.2 Industrial Economics
Numerical data indexing:Percentage 5.90e+00%, Percentage 9.47e+01%, Size 1.50e-02m, Size 2.00e-02m, Size 2.00e-02m to 3.00e-02m, Size 2.60e-01m, Velocity 1.67e+00m/s
DOI:10.11975/j.issn.1002-6819.2018.07.002
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 3>
Accession number:20182405313559
Title:Simulation analysis and verification of heat transfer characteristics of truncated cone helix energy pile
Authors:Liu, Yajiao (1); Huang, Guangqin (1); Lu, Jun (2); Yang, Xiaofeng (1); Zhuang, Chunlong (1)
Author affiliation:(1) Dept. of Military Installation, Army Logistical University of PLA, Chongqing; 401311, China; (2) Faculty of Urban Construction and Environmental Engineering, Chongqing University, Chongqing; 400045, China
Corresponding author:Huang, Guangqin(hgq880818@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:227-234
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to reduce the thermal interference and to improve the heat transfer efficiency, a novel "truncated cone helix energy pile (CoHEP)" was proposed in this study. And in order to simulate the thermal performance of the novel CoHEP more accurately, a three-dimensional numerical model was established with consideration of the inhomogeneous initial soil temperature and the dynamic boundary condition above the soil surface. The heat transfer characteristic of the novel CoHEP of different cone angles was studied. In addition, in order to verify the accuracy of the numerical model, a verification test was conducted. The results showed that the novel CoHEP can be divided into four heat transfer stages along the flow direction: entrance stage → thermal short circuit stage → small temperature difference stage → exit stage. Among them, the heat transfer capacity of the entrance stage was the strongest, and the heat transfer capacity continued to decrease during the thermal short circuit stage and the small temperature difference stage, eventually the heat transfer capacity rebounded during the exit stage. The thermal interference at the bottom of the CoHEP was more serious, and the larger the cone angle, the more serious the thermal interference at the bottom. In contrast, the thermal interference effect was weaker at the top of the CoHEP due to the larger helix radius at the top. The heat flux per unit pipe length of the CoHEP increased linearly with the increase of cone angle. That was because with the same pipe length (L<inf>pipe</inf>), pitch in the depth direction (b) and energy pile height (h<inf>pipe</inf>), increasing the cone angle would increase the top radius (r<inf>t</inf>) of the CoHEP, leading to small thermal interference in the upper part of the CoHEP. At the same time, more high-temperature fluid was located in the upper part of the CoHEP which directly contacted with the covered soil area. Thus the heat transfer capacity increased. When the system operating time was 12 h, the cone angle increased from 0° to 10° to 20°, the increasing rate of the heat flux was 2.54% and 3.53%, respectively. The thermal interference in the upper part of the novel CoHEP was much smaller than that of the traditional CyHEP, and more high-temperature fluid was located in the upper part of the energy pile which was good for heat transfer. In addition, the distance between the adjacent pipes in the axial direction (d) of the novel CoHEP was significantly larger than that of the traditional CyHEP under the same pitch in the depth direction (b), which can effectively reduce the axial thermal interference. Thus the heat flux per unit pipe length of the novel CoHEP was greater than the traditional CyHEP. And when the cone angle was 20°, the heat flux per unit pipe length of the novel CoHEP was 6.16% higher than that of the traditional CyHEP.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Piles
Controlled terms:Computer simulation - Heat flux - Heat pump systems - Heat transfer - Numerical models - Soils
Uncontrolled terms:Different cone angles - Dynamic boundary conditions - Energy piles - Heat transfer characteristics - Heat transfer efficiency - Temperature differences - Thermal interferences - Three-dimensional numerical modeling
Classification code:408.2 Structural Members and Shapes - 483.1 Soils and Soil Mechanics - 616.1 Heat Exchange Equipment and Components - 641.2 Heat Transfer - 723.5 Computer Applications - 921 Mathematics
Numerical data indexing:Percentage 2.54e+00%, Percentage 3.53e+00%, Percentage 6.16e+00%, Time 4.32e+04s
DOI:10.11975/j.issn.1002-6819.2018.07.029
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 4>
Accession number:20182405313542
Title:Optimization of controller parameters based on nondimensional performance indicators for canal systems
Authors:Guan, Guanghua (1); Zhong, Ke (1); Liao, Wenjun (1); Xiao, Changcheng (1); Su, Haiwang (1)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan; 430072, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:90-99
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Automatic canal control plays an increasingly important role in water delivery systems, for it is effective in distributing the water resource rationally and reducing the discharge of wastewater. For the control of an open-canal system, the first issue is how to define the control performance indicator, and then the controller could be designed by pursuing the optimized value of performance indicators. The characteristics of canal systems result in the diversity and complexity of performance indicators, marked by big lag, strong nonlinearity, high coupling and multi-input multi-output (MIMO) topology. Therefore, the objective of this study was to improve the existing performance indicators and propose a general indicator reasonably and overall. We tried to demonstrate the feasibility of them by applying in 2 actual canal systems. In this paper, traditional performance indicators of canal control systems were concluded and analyzed, and some additional indicators were replenished and some of them are nondimensionalized by using the design discharge or constant depth of the control point or other inherent parameters. A set of indicators which can evaluate different canal systems were proposed by weakening the influence of canals' dimension parameters. This set was applied to 2 canal systems with different scales: The large-size canal system is 24 km long × 15 m wide × 6 m deep and the small-size canal system is 18 km long × 5-7 m wide × 2.5 m deep, and the larger is around 20 times the size of the smaller. A simulation model of canal systems' control based on MATLAB was constructed, which consisted of 7 modules: physical model establish of canal systems, steady flow state profile calculation, feedforward control module, feedback control module, gate discharge calculation, gate opening transformation and unsteady flow calculation. Among the models, energy equations and de Saint-Venant system of equations were used to compute the constant flow and unsteady flow, and the canal control system was designed which regarded flow rate as the feedforward and the water level as the feedback. Relying on the imulation model of canal systems' control, we optimized the controller parameter aimed at different nondimensional performance indicators, and conducted the comparison between each other. The simulation proved that the optimal values of indicators had high consistency in the order of magnitude with little concern to the canal scale. For example, the optimal NIAQ (nondimensional integrated absolute discharge change) of both canal systems was 10<sup>-5</sup>. So this series of indicators could be used to compare the performance of different canal systems. However, due to the different optimization effect of single indicator, pursuing the extreme of any single indicator might result in an unbalanced system. Through the analysis of genetic relationship and representativeness among the series of dimensionless performance indicators, a general indicator (GI) was given based on the water level deviation, flow rate changes and transition time with weight. And as far as we're concerned, the control performance was fit for our requirement when the value of GI was no more than 10<sup>-3</sup>in magnitude. The simulation results showed that this aimed GI could stabilize the system and balance all dynamic performances of canal systems well compared with a signal indicator. What was more, we studied the flow and water level procedure lines the canal systems showed under different controller parameters by controlling variable. And we discussed the relationship between proportional-integral-derivative (PID) controller parameters and performance indicators. There existed an insensitive range in which the proportional gain could control the flow rate smoothly in pure proportional (P) controller (proportional gain was smaller than 4 in No.1 canal system, and smaller than 15 in No.2 canal system), and the integral time had a similar effect on water level in proportional-integral (PI) controller. Thus the optimizing method of finding a robust controller was proposed preliminarily: searching the intersection of controller parameters which worked well under different conditions. The series of non-dimensional indicators and GI proposed by this paper can be used to evaluate different canal control systems and different controllers, which can be used as benchmark while designing a new canal control system. This work suggests quite promising solution for the operation of a large number of water delivery systems and irrigation district canal networks in China.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Irrigation canals
Controlled terms:Automation - Benchmarking - Canals - Computer simulation - Control nonlinearities - Controllers - Feedback control - Feedforward control - Hydraulic structures - MATLAB - MIMO systems - Optimization - Proportional control systems - Robust control - Time series analysis - Two term control systems - Unsteady flow - Waste disposal - Water levels - Water resources
Uncontrolled terms:Dynamic performance - Multi input multi output - Nondimensionalize - PI controller parameters - Proportional controller - Proportional integral controllers - Proportional integral derivative controllers - Water delivery systems
Classification code:407.2 Waterways - 444 Water Resources - 452.4 Industrial Wastes Treatment and Disposal - 631.1 Fluid Flow, General - 723.5 Computer Applications - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 732.1 Control Equipment - 921.5 Optimization Techniques - 922.2 Mathematical Statistics
Numerical data indexing:Size 1.50e+01m, Size 1.80e+04m, Size 2.40e+04m, Size 2.50e+00m, Size 5.00e+00m to 7.00e+00m, Size 6.00e+00m
DOI:10.11975/j.issn.1002-6819.2018.07.012
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 5>
Accession number:20182405313539
Title:Fault response characteristics of tractor planetary gearbox based on dynamical simulation and its validation
Authors:Shi, Lichen (1); Li, Kun (1); Wang, Haitao (1); Liu, Yang (1)
Author affiliation:(1) School of Mechanical and Electrical Engineering, Xi'an University of Architecture and Technology, Xi'an; 710055, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:66-74
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The planetary gear set as a new and efficient type of transmission is more and more widely used in many agricultural machinery. The working conditions and environment of agricultural machinery are complex and harsh. Hence the gear cracked, tooth broken and other failures often happen in planetary gearbox. It results that the whole equipment is not stable and cannot meet the farming requirements. More seriously, it can lead the whole equipment to downtime, and lead significant losses to agricultural production in busy seasons. Therefore, it is very important to establish the dynamic model of the planetary gear system and to study the vibration response characteristics based on the fault. And it is of great significance to study the fault mechanism and health monitoring of the planetary gear set in agricultural machinery. Most studies reported in current literature on planetary gearboxes of agricultural machinery have few results based on the vibration mechanism. And most of the dynamics models based on planetary gear system are under health conditions; in addition, they are founded on many assumptions. Even if the dynamics models of planetary gearbox are established under fault conditions, few of them are focused on the studies of fault characteristics under different fault degrees, and the time-varying effects of transmission paths are ignored in these models. Aiming at these shortcomings, this paper took the tractor planetary gearbox as the research object, and a dynamic model of planetary gear sets was established. The model considered the static transmission error, the backlash and the time-varying meshing stiffness of the meshing gear pairs. Furthermore, due to the revolution of planet gears, the transmission path between the meshing points and the sensors is time-varying periodically. The time-varying paths have a modulation effect that can't be ignored on the response signal, which is called the time-varying effects of transmission paths. Thus the time-varying effects of transmission paths at runtime were considered in the model, which was expressed with Hanning function. The Fourier series was used to express the time-varying meshing stiffness, so the problem of the stiffness mutation due to the piecewise function was avoided to some extent. Then the time-varying meshing stiffness under the planetary gear fault conditions was calculated, and the meshing stiffness expression under different gear fault degrees was deduced by introducing fault factor. When the fault factor is equal to 0, it is under heath conditions; when equal to 1, it is under serious failure conditions such as tooth broken; and when the fault factor is in between, it is under minor fault conditions such as gear cracked. The established dynamics model of planetary gearbox system was solved with Runge-Kutta method of variable step size. Using the dynamic model, the fault response characteristics under the conditions of the planetary gears cracked and broken were obtained. The characteristics are that the sidebands appear at the frequency location of k<inf>m</inf>± k<inf>p</inf>± k<inf>c</inf>(where k, m and n are integers, and f<inf>m</inf>, f<inf>p</inf>and f<inf>c</inf>are the meshing frequency, the planet gears' characteristic frequency and the rotating frequency of the planet carrier respectively) in the Fourier spectrum with the localized damage of planet gears, and the peak of spectrum under planetary gears broken is more obvious than under planetary gears cracked. Finally, the simulation signals were compared with the test vibration signals captured from a planetary gearbox fault diagnosis test rig. The test result shows that the vibration signals are modulated by the planet gears' characteristic frequency and the rotating frequency of the planet carrier under the condition of the planet gear fault. Although most of the parameters in the model were optimized, there are also some gaps with the actual situation inevitably. However the spectrum characteristics can basically reflect the actual fault state, and the simulation results and the test results are basically the same. Consequently the comparison showed that the maximum relative errors were 4.65% and 2.32%, and determination coefficients were 0.999 6 and 0.999 8, which verifies the validity of the established model. The model provides a theory basis for health monitoring and fault diagnosis of planetary gearboxes in agricultural equipment.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Fault detection
Controlled terms:Agriculture - Dynamic models - Epicyclic gears - Failure analysis - Fourier series - Gears - Health - Plasma diagnostics - Runge Kutta methods - Stiffness - Tractors (agricultural) - Tractors (truck) - Vibrations (mechanical)
Uncontrolled terms:Agricultural productions - Characteristic frequencies - Determination coefficients - Fault characteristics - Meshing stiffness - Static transmission errors - Time varying meshing stiffness - Vibrations
Classification code:461.6 Medicine and Pharmacology - 601.2 Machine Components - 663.1 Heavy Duty Motor Vehicles - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 931.1 Mechanics - 932.3 Plasma Physics - 951 Materials Science
Numerical data indexing:Percentage 2.32e+00%, Percentage 4.65e+00%
DOI:10.11975/j.issn.1002-6819.2018.07.009
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 6>
Accession number:20182405313567
Title:Analysis on feeding effects of steam explosion and fermentation cotton stalk in sheep
Authors:Guo, Tongjun (1); Zhang, Zhijun (1); Zhao, Jie (2); Sang, Duanji (1); Shi, Yong (3); Cui, Jiwen (3)
Author affiliation:(1) Institute of Feed Research, Xinjiang Academy of Animal Science, Urumqi; 830000, China; (2) Xinjiang Bazhou Grassland Workstation, Kuerle; 841000, China; (3) Xinjiang Hongruida Fiber Company Limited, Kuerle; 841000, China
Corresponding author:Sang, Duanji(542937414@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:288-293
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to investigate the responses of fattening sheep in production performance and blood biochemical parameters to the treatments of steam explosion and fermentation cotton stalk, cotton stalk and corn silage, the whole plant of cotton stalk harvested by self-propelled straw harvester were chopped by grinder, rapid decompression under the 2.5 MPa, 220℃ for 2~3 min, then the cooled product was anaerobically fermented for 45 days by adding inoculants. Thirty healthy sheep with 5-month-old were averagely placed into steam explosion and fermentation cotton stalk, cotton stalk and corn silage group according to their body weight. These sheep were fed with different diets according to their nutrients requirements which were added same dry matter proportion of steam explosion and fermentation cotton stalk or cotton stalk or corn silage to the same basal diet during 40-day experimental period. Daily gain, dry matter intake and blood biochemical parameters were analyzed using the GLM model. The results showed that the dry matter intake was significantly different among groups (P<0.01). The daily gain in steam explosion and fermentation cotton stalk group was 49.21% higher than that in cotton stalk group (P<0.05), the daily gain in corn silage group was 44.45% higher than that in cotton stalk group (P=0.06), The ratio of feed-meat was highest in cotton stalk group and lowest in corn silage group. The blood globulin content in corn silage group were 17.02% and 20.01% lower than steam explosion and fermentation cotton stalk group and cotton stalk group, respectively, both showing significant differences (P<0.05). The blood total protein content in corn silage group was 11.90% lower than cotton stalk group (P<0.01), and was 7.86% lower than steam explosion and fermentation cotton stalk group (P<0.05). The ratio of albumin to globulin in steam explosion and fermentation cotton stalk group was 18.68% lower than corn silage group (P<0.05). The glutamic pyruvic transaminase in cotton stalk group was 69.80% and 77.67% higher than corn silage group and steam explosion and fermentation cotton stalk group, the difference were extremely significant (P<0.01). The Blood cholesterol content in corn silage group was 36.13% lower than cotton stalk group (P<0.05). Low density lipoprotein content in corn silage group was 50% lower than cotton stalk group (P<0.05). The results suggested that the feeding quality of steam explosion and fermentation cotton stalk is higher than cotton stalk but lower than corn silage. The steam explosion and fermentation cotton stalk could reduce the damage to animal gut and obtain a daily gain close to corn silage, but its feed efficiency is higher than corn silage and lower than cotton stalk. The steam explosion and microbial fermentation technology cooperative processing could be help to pre-treat cotton straw as roughage for fattening sheep in the cotton growing area.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Cultivation
Controlled terms:Blood - Cholesterol - Cotton - Explosions - Feeding - Fermentation - Steam - Straw
Uncontrolled terms:Biochemical parameters - Cooperative processing - Daily gain - Glutamic-pyruvic transaminase - Low density lipoproteins - Microbial fermentation - Production performance - Sheep
Classification code:461.2 Biological Materials and Tissue Engineering - 691.2 Materials Handling Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Age 1.10e-01yr, Age 1.23e-01yr, Age 4.17e-01yr, Percentage 1.19e+01%, Percentage 1.70e+01%, Percentage 1.87e+01%, Percentage 2.00e+01%, Percentage 3.61e+01%, Percentage 4.45e+01%, Percentage 4.92e+01%, Percentage 5.00e+01%, Percentage 6.98e+01%, Percentage 7.77e+01%, Percentage 7.86e+00%, Pressure 2.50e+06Pa, Time 1.20e+02s to 1.80e+02s
DOI:10.11975/j.issn.1002-6819.2018.07.037
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 7>
Accession number:20182405313550
Title:Evaluation indicators of cultivated layer soil quality for red soil slope farmland based on cluster and PCA analysis
Authors:Jin, Huifang (1); Shi, Dongmei (1); Chen, Zhengfa (2); Liu, Yijun (1); Lou, Yibao (1); Yang, Xu (1)
Author affiliation:(1) College of Resources and Environment, Southwest University, Chongqing; 400715, China; (2) Kunming Engineering Corporation Limited of POWERCHINA, Kunming; 650051, China
Corresponding author:Shi, Dongmei(shidm_1970@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:155-164
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The minimum data set (MDS) is the least indicators collection that can reflect the information of total soil quality well, which can effectively improve the real-time characteristic and application of soil quality assessment. In order to characterize the soil quality of cultivated layer for slope farmland in southern red soil hilly area, the paper established the MDS for quality diagnosis of cultivated layer for slope farmland by cluster analysis (CA) and principal component analysis (PCA) respectively, and furthermore analyzed soil quality characteristics of cultivated layer adopting 3 different soil quality indices (SQI), including SQI-T (data from total soil indicators), SQI-CA (data from CA indicators) and SQI-PCA (data from PCA indicators). The results showed: 1) Soil quality of cultivated layer for slope farmland varied significantly among different red soil sites. The average cultivated layer thickness of 19.93±4.9 cm was in suitable level for crop growth, and the soil organic matter content of 17.43±8.71 g/kg and the soil total nitrogen content of 0.97±0.42 g/kg were in moderately barren level, but the soil nutrients of effective phosphorus of 26.1±22.22 mg/kg and available potassium of 155.46±88.35 mg/kg were rich for crop growth. The soil pH value of 5.34±0.77 was faintly acidic. 2) The MDS on soil quality diagnosis of cultivated layer for red soil slope farmland included such indicators as cultivated layer thickness, soil bulk density, soil penetration resistance, soil organic substance, pH value and soil available phosphorus. The assessment results of soil quality of cultivated layer based on 3 different data sets are distinct greatly, the variation range and the mean of soil quality index were showed as SQI-T > SQI-CA > SQI-PCA and the variation coefficients presented as SQI-T < SQI-CA < SQI-PCA. Furthermore, the relevance and Nash efficiency coefficient between SQI-CA and SQI-T were higher than that between SQI-PCA and SQI-T, and the relative deviation coefficient and the average relative error between SQI-CA and SQI-T were lower than that between SQI-PCA and SQI-T, which illustrated that MDS-CA (MDS based on CA) was more appropriate than MDS-PCA (MDS based on PCA) to reflect the information of the total data set (TDS) for soil quality assessment of cultivated layer for red soil slope farmland. 3) From the perspective of soil and water conservation, fertilizer conservation and yield-increasing potential, the suitability thresholds of those diagnostic parameters for cultivated layer of red soil slope farmland were indicated as follows: the cultivated layer thickness of ≥20.39 cm, the soil bulk density of 0.92-1.21 g/cm<sup>3</sup>, the soil penetration resistance of ≤1.21 kg/cm<sup>3</sup>, the soil organic matter content of ≥18.82 g/kg, the pH value of 5.04-5.38 and the effective phosphorus content of ≥28.83 mg/kg. Rational deep-loosening is one of the effective measures for reasonable cultivated layer construction. These results can provide some useful parameters not only for the soil quality recovery of the cultivated layer but also for the suitability regulation of the crop growth and the control of soil and water loss of slope farmland, which are also conducive to the sustainable utilization of the slope farmland resources in red soil hilly area.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:39
Main heading:Soils
Controlled terms:Biogeochemistry - Biological materials - Cluster analysis - Crops - Farms - Fish - Organic compounds - pH - Phosphorus - Principal component analysis - Quality control - Soil conservation - Water conservation
Uncontrolled terms:Minimum data set - Real time characteristics - Reasonable cultivated layer - Red soils - Soil and water conservation - Soil organic matter contents - Soil penetration resistance - Soil quality
Classification code:444 Water Resources - 461.2 Biological Materials and Tissue Engineering - 483.1 Soils and Soil Mechanics - 723 Computer Software, Data Handling and Applications - 801.1 Chemistry, General - 801.2 Biochemistry - 804 Chemical Products Generally - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 922.2 Mathematical Statistics
Numerical data indexing:Mass_Density 9.20e+02kg/m3 to 1.21e+03kg/m3
DOI:10.11975/j.issn.1002-6819.2018.07.020
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 8>
Accession number:20182405313563
Title:Design and experiment of automatic sorting and grading system based on machine vision for white agaricus bisporus
Authors:Wang, Fengyun (1); Feng, Wenjie (1); Zheng, Jiye (1); Sun, Jiabo (1); Niu, Luyan (1); Chen, Zhenxue (2); Zhang, Xuetao (2); Wang, Lei (1)
Author affiliation:(1) S&T Information Institution, Shandong Academy of Agricultural Sciences, Jinan; 250100, China; (2) Control Science and Engineering School, Shandong University, Jinan; 250061, China
Corresponding author:Wang, Lei(nkywl@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:256-263
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:White Agaricus bisporus is an excellent source of the B vitamins, riboflavin, niacin, and pantothenic acid and also a good source of the dietary mineral phosphorus. It is one of the most commonly and widely consumed mushrooms in the world. The production of white Agaricus bisporus has been industrialized in China. However, during the last production chain, it needs a lot of labors to sort and grade the white Agaricus bisporus. The manual sorting and grading mode has many disadvantages such as larger error, low productivity, non-uniform standard, and so on. With the development of machine vision technology, it has been successfully used for automatic inspection and sorting, especially in agricultural industry due to its nondestructive characteristic. An automatic sorting and grading system based on machine vision was designed in this paper. Firstly, an automatic sorting and grading hardware system was designed. It included conveying mechanism, image acquiring system, control module and actuator. The conveying mechanism consists of the fixed support, conveyor, roller, driving unit, tension unit, cleaner and guide plate. The image acquiring system consists of a line scan camera, lens, light source and its controller. The control module consists of photoelectric sensor controlling the camera, electromagnetic valve and relay starter controlling the actuator. The actuator consists of the air compressor, duplex pieces, muffler, air cylinder, joints, gas channel, guide rod, slider, connector, flap, baffle, and so on. Secondly, it put forward an image algorithm based on the watershed method, Canny operator, OR operation and closed operation to determine the diameter of white Agaricus bisporus. The first watershed algorithm combining the global threshold segmentation method and maximum entropy threshold segmentation method is used to remove the shadow of image. The second watershed algorithm based on Canny operator, OR operator and closed operation is used to remove the disturbance of petiole. The minimum enclosing rectangle method is used to get the diameter of white button mushroom. Thirdly, a precise control strategy based on the conveyor speed, distance between trigger and flap piece, trigger time and algorithm processing time was designed. Finally, the software based on OpenCV 2.4.10 and Visual Studio 2010 was developed in this paper to acquire, analyze and process the image and output the control instruction to control the valve by USB-4761 module. It also has the visual parameter configuration function for camera, control module and grading standard. When the whole system starts at the first time, the light source of image acquiring system is adjusted by the light controller to make the image clear and stable. The air compressor is powered on and pressurized to the rated pressure of 0.3 MPa. The motor of conveyor is started and the speed of the conveyor belt is adjusted according to the actual production requirement. The white Agaricus bisporus goes into the guide bar with the conveyor belt. When the white Agaricus bisporus goes into the region of image acquiring, it triggers the industrial camera to scan. The image data are transmitted to the industrial computer by image capture card. The software analyzes the image on line. The analyzed result is sent to the related solenoid valve through the digital control module. When the white Agaricus bisporus arrives near the container of related grade, it is sorted into the container by the related flap piece driven by the solenoid valve. In order to validate the applicability and reliability, the test of grading performance and effect was carried out with the prototype of sorting and grading system at 12.7 m/min conveying speed and 1900 Hz line frequency. The results showed that the average maximum grading speed was 102.41 pieces/min, the accuracy of grading was 97.42%, the damage rate was 0.05% and the undetected rate was 0.96%. The grading speed improved by 38.86%, the accuracy improved by 6.84% and the damage rate reduced by 0.13% compared to the manual grading. The system can stably and continuously operate. For long time grading, the advantage of intelligent system is more obvious due to the fatigue of labor. The whole system realizes the on-line automatically sorting and grading for fresh white Agaricus bisporus with the minimum destruction.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Grading
Controlled terms:Actuators - Agricultural machinery - Agriculture - Algorithms - Bacteria - Belt conveyors - Cameras - Computer vision - Controllers - Cylinders (containers) - Digital control systems - Fungi - Gas compressors - Image acquisition - Image analysis - Image processing - Image segmentation - Intelligent systems - Light sources - Maximum entropy methods - Solenoid valves - Solenoids - Sorting - Speed - Watersheds
Uncontrolled terms:Agaricus bisporus - Agricultural industries - Automatic grading - Machine vision technologies - Minimum enclosing rectangle - Production requirements - Threshold segmentation - White button mushrooms
Classification code:444.1 Surface Water - 618.1 Compressors - 619 Pipes, Tanks and Accessories; Plant Engineering Generally - 692.1 Conveyors - 694.2 Packaging Materials - 704.1 Electric Components - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 732.1 Control Equipment - 742.2 Photographic Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment
Numerical data indexing:Frequency 1.90e+03Hz, Percentage 1.30e-01%, Percentage 3.89e+01%, Percentage 5.00e-02%, Percentage 6.84e+00%, Percentage 9.60e-01%, Percentage 9.74e+01%, Pressure 3.00e+05Pa
DOI:10.11975/j.issn.1002-6819.2018.07.033
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 9>
Accession number:20182405313541
Title:Charging and spraying performance test of bipolar contact electrostatic spraying system for unmanned aerial vehicle
Authors:Wang, Shilin (1); He, Xiongkui (1); Song, Jianli (1); Zhong, Chongshan (2); Wang, Zhichong (1); Qi, Peng (1); Ling, Yun (1)
Author affiliation:(1) College of Science, China Agriculture University, Beijing; 100193, China; (2) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China
Corresponding author:He, Xiongkui(xiongkui@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:82-89
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, pesticide application using unmanned aerial vehicle (UAV) has developed rapidly in China. It is very suitable for complex terrain, highly efficient, and capable of dealing with sudden disasters at low risk. Meanwhile, it can reduce the harm of pesticides to human and environmental pollution. However, aerial application is very sensitive to meteorological conditions, which leads to increase of spray drift and nonuniform deposition distribution. A bipolar contact charging electrostatic (BCCE) spraying system for UAV was designed. The electrostatic spray system consisted of power source of electrostatic generator, power source of spray unit, electrostatic generator unit (with power switch and voltage regulator), positive and negative output electrode, tanks, pumps, controller and centrifugal atomizers. The electrostatic generator unit was the key component of BCCE spraying system, which consisted of a negative output electrostatic generator and a positive output electrostatic generator in series connection. The electrostatic generator unit could not only enhance the charging effort but also ensure the electric balance on UAV. The electrostatic spraying system included 2 separate tanks, which were connected to the positive and negative output electrodes of the high voltage electrostatic generator, respectively. So spraying liquid in different tanks was charged positively or negatively, and the charged liquid was atomized into droplets by centrifugal nozzles and then adsorbed onto the leaves of the crop. The output voltage of BCCE spraying system could be adjusted from 15 to 35 kV, and its pump pressure varied from 0.02 to 0.1 MPa. The charge-mass ratio (CMR) and droplet spectrum of spraying liquid for electro-chargeable liquid (ED) and water were measured in the laboratory. The result showed that the volume medium diameter (VMD) of ED was significantly smaller than that of water sprayed by atomizers of BCCE spraying system connected with the positive and the negative output electrode. For water spraying, using BCCE spraying system in different electrostatic voltage (EV), there were no significant differences in VMD and relative span (RS) in both output electrodes; meanwhile, the atomizer of positive voltage could reduce the VMD of ED, while atomizer of negative voltage could enhance the VMD of ED. When the spray liquid was ED, the RSs of droplet spectrum increased as the increase of EV supplied by the positive and negative output electrodes. The test of charging performance showed that the CMR of spray liquids charged by positive and negative output electrodes both increased with the increase of EV. Using the same EV and output electrode, the CMR of water was much higher than ED. With the same EV and spray liquid the CMR charged by negative output electrode was obviously higher than positive output electrode. Experiments were conducted in wheat field, the BCCE spraying system was carried by a single rotor motor UAV 3WQF120-12 to spray ED, and the original spraying system of 3WQF120-12 equipped with 2 LU120-01 nozzles spraying ED and water-based pesticide was chosen for the comparison on pesticide deposition and control effect of wheat aphid and rust. The field experiment result showed that the deposition amounts of both ED treatments were 0.048 6 and 0.051 3 μg/cm<sup>2</sup>, respectively, which were significantly higher than that of the water-based pesticide solution with 0.035 6 μg/cm<sup>2</sup>. The ED treatment sprayed by BCCE spraying system had the best uniformity in deposition with a standard deviation of 0.015 μg/cm<sup>2</sup>and a coefficient of variation of 30.43%. The control efficiency and pesticide persistence of 2 ED treatments on wheat aphid and rust were significantly higher than the conventional water-based treatment. There was no significant difference in control efficiency of rust, and in wheat aphid 14 days after treatment between 2 ED treatments. In addition, the control efficiency of wheat aphid 7 days after treatment for BCCE spraying system was 87.92%, which was significantly higher than that for the UAV's original spraying system that was 76.43%. Therefore, the BCCE spraying system with ED can improve the uniformity of deposition and increase biological control effect.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Pesticides
Controlled terms:Aircraft control - Antennas - Atomization - Atomizers - Centrifugation - Deposition - Drops - Efficiency - Electric machine control - Electrodes - Electrostatic generators - Electrostatics - Flight dynamics - Liquids - Spray nozzles - Spraying - Tanks (containers) - Unmanned aerial vehicles (UAV) - Voltage regulators - Water treatment
Uncontrolled terms:Charge-mass-ratio - Deposition distribution - Droplet spectrums - Electrostatic spraying - Electrostatic voltage - Environmental pollutions - Meteorological condition - Pesticide applications
Classification code:445.1 Water Treatment Techniques - 619.2 Tanks - 631.1 Fluid Flow, General - 652 Aircraft and Avionics - 652.1 Aircraft, General - 701.1 Electricity: Basic Concepts and Phenomena - 731.2 Control System Applications - 732.1 Control Equipment - 802.1 Chemical Plants and Equipment - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 913.1 Production Engineering
Numerical data indexing:Age 1.92e-02yr, Age 3.84e-02yr, Percentage 3.04e+01%, Percentage 7.64e+01%, Percentage 8.79e+01%, Pressure 2.00e+04Pa to 1.00e+05Pa, Surface_Density 1.50e-07kg/m2, Voltage 1.50e+04V to 3.50e+04V
DOI:10.11975/j.issn.1002-6819.2018.07.011
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 10>
Accession number:20182405313535
Title:Dynamic simulation of seed pick-up process and parameter optimization on vacuum plate seeder for rice
Authors:Zhao, Zhan (1); Tian, Chunjie (1); Wu, Yafang (1); Huang, Hedong (1)
Author affiliation:(1) Institute of Agriculture Engineering, Jiangsu University, Zhenjiang; 212013, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:38-44
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The key factor to improve seeds pick-up accuracy of vacuum plate seeder is to control the suction position accurately. During the working progress, the number of seeds in vibrating tray is always changing. So, it is an important guarantee for improving the continuous working performance of seeder that the suction position of vacuum plate can be adjusted automatically according to the variation of seeds in vibrating tray. In the paper, 2 different ellipsoid paddy seeds models were established using multi-sphere fitting method, and the contact forces were calculated using Hertz-Mindlin model. Then, the kinetics simulations of seeds pick-up process were completed using CFD-DEM (computational fluid dynamics- discrete element method) coupling method which includes the standard k-Ε turbulence model and Euler gas-solid two-phase model. According to the spatial distribution variation law of seeds in vibrating tray at different time, their distribution region and discrete coefficients were calculated using the uniform distribution model and the moment estimate algorithm. Discrete motion states and stability characteristics of seeds under excitation of vertical reciprocating vibration were obtained, and the reasonable range of seeds layer thickness was determined. Seeds pick-up processes were finished when the seeds were thrown up to the high point by vibrating tray, and the absorbed seeds were generally in the upper layer. Under the conditions that seeds could be picked up accurately, the critical suction position in different seeds layer thickness was determined, and then the variation of pick-up distance, the influence of seeds shape on the pick-up performance, and the reasons leading to seeds single pick-up, missing pick-up and repeated pick-up were analyzed. It was obtained that the repeated pick-up ratio will increase with the increasing of seeds ellipticity which leads to the strong leakage flow field. Under the influence of collision and extrusion between seeds, the pick-up distance received by simulations is less than the value at static condition. Considering the influence of uncertain motion state of seeds in actual vibrating tray is much stronger, a modification method of suction position was proposed to improve the overall seeds pick-up performance of vacuum plate. That is to properly reduce the regulated distance based on the critical suction position received by simulation. Combined with the real-time monitoring method of seeds mass, an adaptive control device of suction position of vacuum plate was designed using PLC (programmable logic controller) as the controller. Using the established suction position control model, and taking differential pressure, regulated distance of suction position, vibration frequency of tray and seeds layer thickness as factors, each nozzle picking-up 1-2 seeds as evaluating indicator, the orthogonal tests were carried out on precision seeder test-rig with the diameter of suction nozzle of 2.5 mm and vibration amplitude of tray of 4 mm. The mathematical regression equation of seeds pick-up qualified index was established based on orthogonal tests results, and it was shown that the differential pressure and regulated distance of suction position were the 2 major factors that affected operating performance. By optimizing the established mathematical regression equation, the ideal working parameters were received including differential pressure of 4.4 kPa, vibration frequency of 10.6 Hz, and regulated distance of suction position of 2.7 mm. Under the above optimization parameters, further seeds pick-up tests were carried out with the seeds layer thickness varying in the range of 15-25 mm, and the results indicated that the seeds pick- up qualified index could reach about 94.5%. The proposed control method of suction position according to the variation of seeds layer thickness in vibrating tray can provide references for improving automation level and operating performance of vacuum plate precision seeder.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:36
Main heading:Position control
Controlled terms:Computation theory - Computational fluid dynamics - Controllers - Machinery - Mechanization - Mindlin plates - Models - Nozzles - Optimization - Pickups - Turbulence models - Two phase flow
Uncontrolled terms:Control methods - Differential pressures - Optimization parameter - Parameter optimization - PLC (programmable logic controller) - Precision seeder - Suction position - Vacuum plates
Classification code:408.2 Structural Members and Shapes - 601 Mechanical Design - 631.1 Fluid Flow, General - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723.5 Computer Applications - 731.3 Specific Variables Control - 732.1 Control Equipment - 921.5 Optimization Techniques
Numerical data indexing:Frequency 1.06e+01Hz, Percentage 9.45e+01%, Pressure 4.40e+03Pa, Size 1.50e-02m to 2.50e-02m, Size 2.50e-03m, Size 2.70e-03m, Size 4.00e-03m
DOI:10.11975/j.issn.1002-6819.2018.07.005
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 11>
Accession number:20182405313543
Title:Coupling optimization model embedded groundwater dynamic model for distribution of pumping wells in well irrigation area
Authors:Jia, Yanhui (1, 2); Fei, Liangjun (1); Huang, Xiuqiao (2); Li, Jinshan (1, 2); Zhai, Guoliang (2)
Author affiliation:(1) Water Resource Research Institute, Xi'an University of Technology, Xi'an; 710048, China; (2) Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Xinxiang; 453002, China
Corresponding author:Huang, Xiuqiao(huangxq626@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:100-106
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is important to study the method of well layout to reduce the irrigation energy consumption and to promote the sustainable utilization of water resources. This paper aimed to explore the suitable layout method of well to reduce the water consumption in well-irrigation area. The optimization model of well layout was constructed with the minimum cost of water intake, in which the groundwater dynamic model (Modflow-2000) was embedded. And the data were exchanged through the common parameters of the 2 models, thus forming the coupling model of well layout. Based on the measured data, the trend of the observation value of the water level was consistent with that of the calculated value at different time after the corresponding parameters of the model were determined. And the mean value of the absolute relative error was 0.88%, and RMSE (root mean square error) value was 0.135 3 m, which could meet the accuracy requirements of the optimal allocation of groundwater resources. It showed that the model could reflect the actual change trend of groundwater level in irrigation area. Finally, taking Tongliao well-irrigation area in Inner Mongolia as the research object, the golden section search method was used to find the optimal positions of the pumping wells. The fluctuation of the water level in wells showed that the irrigation quota in the research area was too large and the irrigation water should be reduced to keep the water resource balance. The results of single well optimization were different from those of the existing well-spacing method. It was found that there were no irrigation wells in the northeastern uncultivated land and villages, and the optimal well location was not in the center position of adjacent 2 wells in the single well optimization results. From the results of global optimization, there was a great change in the distribution of wells compared with the current method of well spacing. And the cumulative value of drawdown in single water extraction could reduce by 5.96 m, and the average value of drawdown could reduce by 0.134 m, which had a certain effect on the decrease of energy consumption in the community. The groundwater movement is a complex system and the model generalization is simpler. Moreover, there is a certain gap with the real flow field. But the application of the coupling model to the optimization of the distribution of well group can also be explained to some extent. The optimization process of single well has reached automatic optimization, and the Modflow-2000 model averagely needs to be operated 10 times in single operation. Meanwhile, the time for single well is about 8 min long. But the process of multi-well optimization is cumbersome. If the model scenario is set to the foundation pit dewatering and the well is set around the foundation pit, the coupling model can optimize the dewatering of the foundation pit; if the water injection is adjusted, the coupling model can also optimize the layout of the artificial recharge well.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Injection (oil wells)
Controlled terms:Couplings - Dewatering - Dynamic models - Energy utilization - Global optimization - Groundwater - Groundwater resources - Irrigation - Mean square error - Oil well flooding - Optimization - Water injection - Water levels - Water supply - Well pumps - Well spacing - Wells
Uncontrolled terms:Automatic optimization - Coupling optimization - Foundation pit dewatering - Golden section search - MODFLOW - Optimization modeling - RMSE (root mean square error) - Sustainable utilization
Classification code:444.2 Groundwater - 446.1 Water Supply Systems - 511.1 Oil Field Production Operations - 525.3 Energy Utilization - 612.1 Internal Combustion Engines, General - 618.2 Pumps - 802.3 Chemical Operations - 821.3 Agricultural Methods - 921 Mathematics - 921.5 Optimization Techniques - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 8.80e-01%, Size 1.34e-01m, Size 5.96e+00m, Time 4.80e+02s
DOI:10.11975/j.issn.1002-6819.2018.07.013
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 12>
Accession number:20182405313534
Title:Improvement of mechanical properties and wear resistance of cotton picker spindle by electromagnetic treatment
Authors:Zhang, Youqiang (1, 2); Cai, Zhipeng (2); Tian, Yu (2); Meng, Yonggang (2)
Author affiliation:(1) School of Mechanical and Electrical Engineering, Key Laboratory of Modern Agricultural Engineering, Tarim University, Alar; 843300, China; (2) State Key Laboratory of Tribology, Tsinghua University, Beijing; 100084, China
Corresponding author:Meng, Yonggang(mengyg@tsinghua.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:31-37
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cotton is one of the major crops in Xinjiang, China, and has a significant impact on Xinjiang's economic development and social stability. The mechanization degree of cotton harvest is increasing with the development of productive forces and the progress of science and technology. For part of the mission field of Xinjiang Production and Construction Corps, China, mechanized harvesting has been achieved 100%, and overall, it has reached above 85%. Spindles are the core component of cotton picker; a single cotton picker has about 2 500 spindles, and a spindle uniquely has the structure of 3 rows × 14 teeth. In order to facilitate the removal of cotton, the first 3 teeth have an angle of 30° with respect to the pole axis, and the remaining 11 hook teeth form an angle of 45° to ensure the cotton picking rate, whose performance directly determines operation efficiency and cotton quality of the cotton picker. Moreover, the substrate material of the spindle is low carbon alloy steel, on which a chromium coating is electroplated to increase the wear resistance. In the case of correct installation and good lubrication, the average life span of spindle was picking cotton of about 400 ha. The wear resistance of the surface coating seriously affects the running cost of the cotton picker. Therefore, to further improve the wear resistance of spindle has always been a scientific and technical issue. In order to improve the wear resistance of the spindle, we have proposed electromagnetic treatment method for surface modification of spindle (Case's spindle made by Case Corp., USA, Deere's spindle made by John Deere Corp., USA and Yeer's spindle made by Yeer Corp., China). The main objective of this study was to reveal the mechanical properties of the electromagnetic treated spindle, but not changing the spindle structure that has been existing in cotton picker. The result showed that the residual stress of the 3 types of spindles was decreased significantly after electromagnetic treatment, the residual stress of Case's and Yeer's spindle decreased by 60%, and that of Deere's spindle by about 50%. The main cause of residual stress decrease was that electromagnetic treatment can cause stress relaxation in the material, resulting in local inelastic deformation and stress redistribution, and improve the fatigue life. After electromagnetic treatment, the microhardness of the spindle's substrate material and the nanohardness of the electroplated chromium coatings did not change significantly, and the elastic modulus of the coating decreased. The ratio of elastic modulus to hardness of the 3 kinds of spindle surface coating was all over 21 before electromagnetic treatment. After electromagnetic treatment, the ratio value of Case's, Deere's and Yeer's spindle was 18, 17 and 20, respectively. The decrease of the ratio of elastic modulus to hardness will increase the elastic deformation, reduce the adhesion and wear, and improve the wear resistance. Through the scratch and wear test, the scratch depth of the spindle surface coating became smaller and the wear scar width decreased after electromagnetic treatment for all kinds of spindles. The wear scar width of Case's and Yeer's spindle decreased more significantly than Deere's spindle. Moreover, the wear scar width decreased with the increase of load in wear test, but the downtrend of wear scar width of Case's and Yeer's spindle was more obvious than Deere's spindle compared with that before electromagnetic treatment. By the comparison, the improved wear resistance of Case's spindle is the most notable after the electromagnetic treatment. Therefore, the Case's spindle of electromagnetic treatment is used to carry out the field test for cotton picking, which was to evaluate and verify wear resistance. The research results will be helpful for improving the wear resistance of spindle, which makes it possible to prolong the service life of spindle used, and has important social significance and remarkable economic benefits.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Wear resistance
Controlled terms:Alloy steel - Chromium - Cotton - Economic and social effects - Economics - Elastic moduli - Fatigue of materials - Hardness - Harvesters - Low carbon steel - Machinery - Magnetic materials - Mechanical properties - Metal coatings - Residual stresses - Stress relaxation - Surface resistance - Surface treatment
Uncontrolled terms:Electromagnetic treated - Electromagnetic treatments - Inelastic deformation - Low-carbon alloy steels - Mechanized harvesting - Operation efficiencies - Science and Technology - Spindle
Classification code:543.1 Chromium and Alloys - 545.3 Steel - 708.4 Magnetic Materials - 813.2 Coating Materials - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 931 Classical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science - 971 Social Sciences
Numerical data indexing:Percentage 1.00e+02%, Percentage 5.00e+01%, Percentage 6.00e+01%, Percentage 8.50e+01%
DOI:10.11975/j.issn.1002-6819.2018.07.004
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 13>
Accession number:20182405313546
Title:Soil moisture estimation based on GPR power spectrum and envelope amplitude in sand loam
Authors:Cui, Fan (1); Chen, Baiping (2); Wu, Zhiyuan (3); Nie, Junli (4); Li, Siyuan (2); Geng, Xiaohang (2); Li, Shuai (2)
Author affiliation:(1) State Key Laboratory of Coal Resources and Safe Mining, China University of Mining Technology (Beijing), Beijing; 100083, China; (2) College of Geoscience and Surveying Engineering, China University of Mining Technology (Beijing), Beijing; 100083, China; (3) College of Safety Engineering, North China Institute of Science & Technology, Langfang; 065201, China; (4) Key Lab of Karst Environment and Geohazard, Ministry of Land and Resources, Guizhou University, Guiyang; 550025, China
Corresponding author:Nie, Junli(38240493@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:121-127
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The soil water is of great significance to the management and restoration of the ecological environment in western China. In order to realize an accurate, rapid and continuous detection of the distribution of water content in the shallow sandy loam by virtue of the ground penetrating radar (GPR) technology, 2 means were thus used including radar wave average envelope amplitude (AEA) and auto-regressive and moving average (ARMA) power spectrum recognition, which were also utilized to invert the water contents of the shallow sandy loam soils. AEA was used to analyze and establish the relationship between the radar early-time average amplitude envelope signal value and the dielectric constants of surface strata with depth less than 1 m. ARMA power spectrum recognition was used to build the relation between power spectrum and water contents of the sandy loam soils with depth range within radar's maximum detection depth. The sandy loam soils with different water contents could differentiate the distribution of the envelopes of power spectrum. The variation of different frequency spectrum energy was related to the water contents in soil samples, which could be shown by the distribution of the high and low frequency envelopes. After the comparison of the water contents inverted by AEA, ARMA and drilling sampling, it was found that the water contents of the shallow sandy loam soils inverted by ARMA was effectively in the depth of 0-10 m. But the results were inaccurate in the depth of 0-0.5 m. However, the AEA provided accurate water contents of the shallow sandy loam soils in the depth of 0-0.5 m. The correlation coefficients of volumetric water contents derived by drilling sampling and inverted by ARMA were 0.57, 0.62, 0.96 and 0.99 respectively in the depth of 0, 0.5, 1.0 and 10.0 m, with the corresponding mean relative errors of 47.37%, 30.32%, 11.20%, and 16.71%. The volumetric water contents derived by AEA almost equaled the values derived by drilling sampling in the depth of 0-0.5 m. The correlation coefficient of volumetric water contents derived by drilling sampling and AEA were 0.98, 0.99 in the depth of 0-0.5 m respectively, but the correlation coefficient was only 0.07 when the depth was 1.0 m. Based on the applicability of the 2 methods, a joint model was established to invert the water contents of the shallow sandy loam soils in the depth of 0-10 m in the typical arid area of western China. The actual detection showed that the average relative error between the water contents and the drying method of the joint model in the range of 0-0.5 m decreased by 16.81%-41.80% compared to that of ARMA. Compared with AEA, the joint model could invert the water contents of deeper strata. The joint method had the average relative error and root mean square error was 5.57%-16.71% and 0.62%-2.08%, respectively. It indicates that the joint model can quickly, accurately and continuously obtain the volumetric water contents of the shallow sandy soils in the depth range varying from 0-10 m in the arid area of western China.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Water content
Controlled terms:Arid regions - Errors - Geological surveys - Geophysical prospecting - Ground penetrating radar systems - Infill drilling - Mean square error - Power spectrum - Radar signal processing - Soil conditioners - Soil moisture - Soils - Tracking radar
Uncontrolled terms:Average envelope amplitude - Correlation coefficient - Different water contents - Ground penetrating radar (GPR) - Moving averages - Root mean square errors - Soil moisture estimation - Volumetric water content
Classification code:443 Meteorology - 444 Water Resources - 481.1 Geology - 481.4 Geophysical Prospecting - 483.1 Soils and Soil Mechanics - 511.1 Oil Field Production Operations - 716.2 Radar Systems and Equipment - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 1.12e+01%, Percentage 1.67e+01%, Percentage 1.68e+01% to 4.18e+01%, Percentage 3.03e+01%, Percentage 4.74e+01%, Percentage 5.57e+00% to 1.67e+01%, Percentage 6.20e-01% to 2.08e+00%, Size 0.00e+00m to 1.00e+01m, Size 0.00e+00m to 5.00e-01m, Size 1.00e+00m, Size 1.00e+01m
DOI:10.11975/j.issn.1002-6819.2018.07.016
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 14>
Accession number:20182405313533
Title:Optimal design on auto obstacle avoidance mechanism of intra-row weeder for trellis cultivated grape
Authors:Xu, Liming (1); Yu, Changchang (1); Liu, Wen (1); Yuan, Quanchun (1); Ma, Shuai (1); Duan, Zhuangzhuang (1); Xing, Jiejie (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing; 100083, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:23-30
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:At present, in the trellis vineyard, the methods of mechanical weeding are mainly divided into inter-row mechanical weeding and intra-row mechanical weeding. The development of intra-row mechanical weeding is relatively slow, because the identification and location for crop and weed is difficult in the process of mechanical weeding. Now, the theoretical study on intra-row mechanical weeding of trellis cultivated grape is not very much. In order to achieve the intra-row weeding of trellis cultivated grape, this paper designs an auto obstacle avoidance mechanism based on the existing weeder, which includes parallel four-bar linkage mechanism and trigger mechanism of obstacle avoidance. The contact rod is composed by 2 straight lines and an arc connecting straight lines in the trigger mechanism of obstacle avoidance. And the theoretical working principle of auto obstacle avoidance mechanism is described. After the pre-test, it is found that the length of the straight section of the first section of the rod, the arc angle of the intermediate transition arc and the 3 distances between the contact rod and the edge of the weeding part have obvious effect on the result of weeding. So a virtual prototype model for auto obstacle avoidance mechanism is built in ADAMS, and the trigger mechanism of obstacle avoidance is parameterized. Then, the orthogonal test is conducted by taking the combination of 3 distances between contact rod and edge of weeding part and the length of the first part of the rod as the test factors and the area which is not covered by the weeding parts after the work as the experimental index. The results show that the combination of 3 distances and its interaction with the arc angle of intermediate transition are significant factors. In order to analyze the effect of the combination of 3 distances on the area not covered by the weeding parts after the work deeply, the length of the first part of the rod is set as 1050 mm, the arc angle of intermediate transition is 85°, the forward speed is 390 mm/s, the initial velocity of the cylinder is 50 mm/s, and furtherly taking the parameter the combination of 3 distances as the test factor and the area not covered by weeding parts after the work as the experimental index, the optimization simulation is conducted. The results show that the optimal value is obtained when the 3 distances between contact rod and edge of weeding part are 225, 300, and 212 mm, respectively. The area not covered is 783 mm<sup>2</sup>except the scheduled area which is not needed to weed. It is very small, so the weeds can be considered to be removed completely, which shows the result of weeding is good. On the basis of simulation optimization, the field tests of single obstacle avoidance and continuous obstacle avoidance are also carried out, in which the combination of 3 structural parameters of the obstacle avoidance mechanism is set as variable and the parameters such as length of the first part of the rod and arc angle of the intermediate transition arc as constant values. The field test results show that the average coverage rate of weeding operation after optimization is 97.5%, which is about 8% higher than before, and the standard deviation is 2.98%, which is lower than before. The stability of weeding is also better, and the effect of optimization is obvious. Generally, this study enriches the method of identification and location for crops and weeds in the process of mechanical weeding, and also provides reference for the improvement of the design of intra-row weeder for trellis cultivated grape.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Machine design
Controlled terms:Agricultural machinery - Collision avoidance - Crops - Design - Experiments - Optimal systems - Optimization - Testing
Uncontrolled terms:Intra-row - Method of identifications - Optimization-simulation - Simulation optimization - Structural parameter - Trellis cultivated grape - Virtual prototype models - Weeder
Classification code:601 Mechanical Design - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 914.1 Accidents and Accident Prevention - 921.5 Optimization Techniques - 961 Systems Science
Numerical data indexing:Area 7.83e-04m2, Percentage 2.98e+00%, Percentage 8.00e+00%, Percentage 9.75e+01%, Size 1.05e+00m, Size 2.12e-01m, Velocity 3.90e-01m/s, Velocity 5.00e-02m/s
DOI:10.11975/j.issn.1002-6819.2018.07.003
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 15>
Accession number:20182405313555
Title:Tractor driver fatigue detection based on convolution neural network and facial image recognition
Authors:Lu, Wei (1, 2); Hu, Haiyang (1); Wang, Jiapeng (1); Wang, Ling (1); Deng, Yiming (3)
Author affiliation:(1) Department of Engineering, Nanjing Agricultural University, Nanjing; 210031, China; (2) Jiangsu Province Engineering Laboratory of Modern Facility Agriculture Technology and Equipment, Nanjing; 210031, China; (3) Michigan State University, College of Engineering, East Lansing; 48824, United States
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:192-199
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Tractor is a popular tool for agricultural farming in the world. But many factors such as high labor intensity, absence of sleeping and monotonous environment make driver fatigued easily in farming season. Aiming at the phenomenon of fatigue driving which is the major reason for tractor traffic accidents, a tractor fatigue detection method based on facial feature recognition using convolution neural network was proposed. Firstly, 1200 driving images were sampled during different daytimes by 60 drivers in which the male accounted for 77%. Then the face images of tractor drivers were pretreated by gamma intensity correction (GIC) method, aimed to solve the problem of the uneven brightness of images with fast processing speed because of its simple algorithm, and hence reduce the influence of illumination of faces. Due to the complex working environment of the tractor and the special surrounding window design, wavelet denoising method was applied in image denoising because it is powerful for the removal of impulse noise and Gaussian noise which are the main noise in the images. In addition, principal component analysis - skin color model (PCA-SCM) method was used to detect and locate faces and then skin color model was applied to rectify and extract the facial area. For improving the face recognition precision, dual-face recognition and checking algorithm was proposed. Firstly, core feature face database was established and human face recognition classifier was generated. Secondly the core feature memory space of human face was formed to locate human face in image. Thirdly, to establish a Gaussian skin color model in YCbCr color space and perform the binary converting, bloat and corrosion methods were also applied to remove fake areas for improving accuracy. In the end, the obtained face position was compared with the previous one to evaluate the effectiveness of this image. Finally, the drivers' facial images were input to the convolution neural network (CNN) for training, and the driver fatigue detection model was established to identify the fatigue of tractor driver based on the face image. The neural network was mainly composed of an input layer, 2 convolution layers, 2 pooling layers, 2 fully connected layers and an output layer. The batch size was 30, and the convolution layer sampled 16 channels of input layer. After reducing the dimension of the feature map by the pooling layer, the full connection layer classified the extracted features and then the correctness rate and the loss rate were obtained. The AdamOptimizer was selected as the optimizer to improve the gradient descent by using the momentum (moving average of the parameters). The hyperparameters were dynamically adjusted to minimize the loss function of the network to achieve better discrimination. Additionally, the changes of weight parameter and bias parameter in convolutional layer and all-connected layer were analyzed, as well as the change trend of correctness rate and loss rate. The T-SNE dimensionality reduction iterative analysis was applied in CNN training. Compared with other methods of fatigue driving detection, such as dynamic template matching and BP (back propagation) neural network, CNN has obvious advantages in detecting correctness and detecting speed. Due to the unique convolutional kernel structure of CNN, more and more useful information in the image can be extracted more efficiently and quickly. CNN still has good detection efficiency compared with the fuzzy inference detection method. Experiments showed that the proposed detection model's accuracy rate is 98.9%, and the recognition time for each frame of image is 38 ms (Using Inter i7-4510U dual-core processor), which demonstrate that the proposed image processing method using CNN can realize fatigue detection of tractor driver in real time.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:40
Main heading:Face recognition
Controlled terms:Backpropagation - Classification (of information) - Color - Color codes - Convolution - Corrosion - Fuzzy inference - Gaussian noise (electronic) - Image denoising - Image processing - Impulse noise - Iterative methods - Principal component analysis - Processing - Template matching - Tractors (agricultural) - Tractors (truck)
Uncontrolled terms:Alogrithms - BP (back propagation) neural network - Convolution neural network - Dimensionality reduction - Facial image recognition - Image processing - methods - PCA-SCM - Wavelet denoising method
Classification code:663.1 Heavy Duty Motor Vehicles - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 741.1 Light/Optics - 913.4 Manufacturing - 921.6 Numerical Methods - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 7.70e+01%, Percentage 9.89e+01%, Time 3.80e-02s
DOI:10.11975/j.issn.1002-6819.2018.07.025
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 16>
Accession number:20182405313545
Title:Calculation of water hammer pressure of flow pipeline based on modified four-equation friction model
Authors:Wang, Zhenhua (1, 2); Ma, Xihe (1, 2); Li, Wenhao (1, 2); Zheng, Xurong (1); Zhang, Jinzhu (1)
Author affiliation:(1) College of Water and Architectural Engineering, Shihezi University, Shihezi; 832000, China; (2) Key Laboratory of Modern Water-Saving Irrigation of Xinjiang Production and Construction Corps, Shihezi; 832000, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:114-120
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Water hammer problem is a problem that often occurs in the pipeline and is difficult to control. Friction coupling is a boundary contact coupling formed by the relative motion between the fluid and the wall of the tube to produce viscous friction. In the range of high frequency motion of the fluid, the characteristics of the friction coupling become more complex, which will directly affect the water hammer evolution of the pipeline system. At present, most numerical models of water hammer calculation are based on the constant flow friction equation of one-dimensional water hammer, ignoring the wall shear stress and convection item, and the attenuation and waveform distortion processes of water hammer pressure wave are difficult to make an accurate calculation. There are few studies on the friction coupling and connection coupling and convection term as to the pipe fluid water hammer calculation. Unsteady friction models are only validated with uncoupled formulation. Additionally, coupled models such as four-equation model (4EM), provide more accurate prediction of water hammer since fluid-structure interaction (FSI) is taken into account, but they are limited to steady-state friction formulation. In this paper, the four-equation friction model (4EFM) based on Zielke model and FSI 4EM is modified according to the one-dimensional unsteady flow shear stress on tube wall, which was derived from the extended irreversible thermodynamics (EIT) by Axworth and others, and the modified 4EFM can accurately reflect the influence of the unsteady friction term on the water hammer wave. In the self-pressure pipeline water delivery project on Hongxing Farm of Thirteenth Division, Xinjiang Production and Construction Corps, the closed valve water hammer test was performed, this model was applied to quasi rigid pipeline with axial movement valve, and the numerical calculation of closed valve water hammer in the pipeline was carried out by using the method of characteristics (MOC) with the MATLAB software. Then the accuracy of Zielke model, 4EM, 4EFM and modified 4EFM in the simulation of water hammer of the pipeline was compared and analyzed. The results show that under the friction coupling and junction coupling condition, Zielke model and 4EM are not suitable for calculating the change of pipeline water hammer, and numerical oscillation and the error are serious, in the third s two model pressure decay process, compared with measured data of early 0.5 s, phase deviation. The modified 4EFM and 4EFM can accurately describe the distortion and attenuation process of pressure wave after a cycle, the simulation deviation will not increase with time, the phase deviation is small, and the fit degree is high. The modified 4EFM has better consistency with the measured value through the comparison. The 4EFM and other calculation models have better consistency. The peak error of water hammer pressure in each cycle for the modified 4EFM is basically less than 1.5%, which is better than 4EFM with the pressure peak error of more than 3%. In practical engineering, in addition to the impact of objective conditions, water hammer pressure calculated by the modified 4EFM has high fitting degree with the tested data, as well as water hammer wave form and time, and this method can accurately capture the characteristics of the early change of pressure in long distance pipeline, the water hammer wave attenuation and the phase shift, so the modified model can be applied in water hammer calculation during long distance water transfer process of gravity flow with the computer. And the reduction of the time step of the operation can improve the simulation precision of the modified 4EFM. At present, the effect of the modified 4EFM on the calculation of water hammer in the environment of viscoelastic tube and multiphase flow still needs further verification.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Water hammer
Controlled terms:Computational fluid dynamics - Computer simulation - Couplings - Errors - Fluid structure interaction - Friction - High pressure engineering - MATLAB - Numerical methods - Numerical models - One dimensional - Pipelines - Shear flow - Shear stress - Software testing - Thermodynamics - Tribology - Unsteady flow - Water pipelines
Uncontrolled terms:Extended irreversible thermodynamics - Long distance pipelines - Long distance water transfer - Method of characteristics - One dimensional unsteady flow - Simulation of water hammers - Unsteady friction models - Water hammer pressure
Classification code:619.1 Pipe, Piping and Pipelines - 631.1 Fluid Flow, General - 632.2 Hydraulic Equipment and Machinery - 641.1 Thermodynamics - 723.5 Computer Applications - 921 Mathematics - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 1.50e+00%, Percentage 3.00e+00%, Time 5.00e-01s
DOI:10.11975/j.issn.1002-6819.2018.07.015
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 17>
Accession number:20182405313536
Title:Hydraulic performance analysis and optimization on flow passage components of diving tubular pumping system
Authors:Xia, Chenzhi (1); Cheng, Li (1); Jiang, Hongying (2); Xin, Jian (3)
Author affiliation:(1) School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou; 225127, China; (2) Jiangsu Province Water Engineering Sci-tech Consulting Co., LTD, Nanjing; 210029, China; (3) Jiangsu Yatai Pump and Valve Co., LTD, Taizhou; 225400, China
Corresponding author:Cheng, Li(chengli@yzu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:45-51
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Diving tubular pump is a kind of low-head large-flow horizontal pump. This type is postpositive bulb pump and the motor is coaxial with pump, which is suitable for irrigation or storm drainage pumping station. For the advantages of excellent hydraulic performance, compact structure, good noise resistance and low operating cost, diving tubular pump is widely applied in low head pumping station. The internal structure of diving tubular pumping system is more complex than other pumping systems for the combination of motor and rotor. Bulb, support slices, cable hole, inlet passage and outlet passage constitute the flow passage components of diving tubular pumping system, which have influence on the internal flow pattern and hydraulic loss of diving tubular pumping system. For low head condition, small increase of hydraulic loss will result in large efficiency loss of pumping system. So the analysis on hydraulic performance of flow passage components of diving tubular pumping system needs to be carried out. In this paper, to acquire hydraulic performance of flow passage components, the inner flow field of diving tubular pumping system is calculated by CFD (computational fluid dynamics). The influence on hydraulic performance of pumping system with different flow passage components is analyzed and the experiment is performed to verify the result of numerical calculation. The head and efficiency difference between model test and CFD simulation are less than 1% in the best efficiency point condition, and the high efficiency range predicted by CFD coincides with the results of the experiment. In order to acquire the influence on hydraulic performance for different numbers of support slices, 3 kinds of slices' numbers are simulated to show that the number of support slices affects the flow pattern between guide vane and support slice. The hydraulic loss of bulb part increases with the number of support slices. The hydraulic loss of pumping system is relatively lower while the support slices' number is equal to guide vane's, which is 5 in this pumping system. Also the shape of bulb tail of pumping system has influence on the flow pattern in outlet passage. Three kinds of bulb tail shapes are calculated, including cone, semi-ellipsoid and semi-sphere. Cone is bad shape for bulb tail, due to the bad flow pattern caused by blunt tail. Semi-sphere is better than cone for less hydraulic loss and better flow expansion in outlet passage. Compared to cone and semi-sphere, semi-ellipsoid is the best shape for bulb tail, which can prevent bad flow pattern like backflow and flow separation. Cable hole is a small pipe which locates at bulb, and its influence on flow pattern and hydraulic loss is ignored by manufactures for its small volume. This paper compares 2 different section shapes of cable hole, specific circle and streamline shape. The result shows that cable hole causes 16% hydraulic loss of bulb, and streamline shape acquires better pressure distribution on cable hole and slightly enhances the flow pattern behind cable hole. Besides, the combination of cable hole and support slice can improve the flow pattern in bulb part and improve efficiency of pumping system. The transition shape of inlet passage between 2 gate slots is also a key factor on hydraulic performance of diving tubular pumping system. Two transition shapes are calculated, including converging square pipe and converging square-circle pipe. Compared with converging square-circle pipe, converging square pipe decreases hydraulic loss of pumping system by 5% and acquires better flow pattern around gate slots. In addition, the other advantage of converging square pipe is the convenience for construction. In conclusion, the efficiency of optimized diving tubular pumping system increases by 2.5%, which reaches 78%. In best efficiency point, the uncertainty of hydraulic performance between simulation and test result less than 1%.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Computational fluid dynamics
Controlled terms:Cables - Computer simulation - Efficiency - Flow patterns - Flow separation - Optimization - Pumping plants - Pumps - Spheres
Uncontrolled terms:Best efficiency point - CFD (computational fluid dynamics) - Flow passage - Internal flow patterns - Low-head pumping stations - Model tests - Numerical calculation - Tubular pumps
Classification code:446 Waterworks - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 723.5 Computer Applications - 913.1 Production Engineering - 921.5 Optimization Techniques
Numerical data indexing:Percentage 1.00e+00%, Percentage 1.60e+01%, Percentage 2.50e+00%, Percentage 5.00e+00%, Percentage 7.80e+01%
DOI:10.11975/j.issn.1002-6819.2018.07.006
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 18>
Accession number:20182405313537
Title:Microstructure and tribology characteristics of head and chest exoskeleton of Procambarusclarkii
Authors:Zhang, Zhihong (1, 2); Zhang, Guangkai (1); Tong, Jin (3); Lai, Qinghui (1); Gao, Xuhang (1); Tang, Ying (4); Carr, Stephen (5)
Author affiliation:(1) Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming; 650500, China; (2) United States Department of Agriculture, Agricultural Research Service, 1680 Madison Ave., Wooster; OH; 44691, United States; (3) The Key Laboratory of Bionic Engineering, Jilin University, Changchun; 130025, China; (4) The Electron Microscopy Laboratory, Kunming Medical University, Kunming; 650500, China; (5) International Soil and Water Renewables, LLC, Salem; IN; 47167, United States
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:52-58
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Procambarusclarkiihas remarkable ability to burrow and move efficiently underground through a range of harsh and paddy soil environments. To investigate the friction and wear behavior of Procambarusclarkii, its head and chest exoskeleton were chosen as the object of this study. The content and presence of inorganic elements in exoskeleton were analyzed by X-ray fluorescence spectrometer (AxiosMAX, PANalytical, Netherland) and X-ray diffractometer. The microstructure of the exoskeleton of the head and chest was observed by field emission scanning electron microscopy (NovaNano-SEM450, FEI, USA). The hardness and elastic modulus of the thoracic and lateral exoskeleton were measured by nanoindentation system(NanoindenterG200-MTSNanoInstruments). The JLTB-02 friction and wear tester (JLTB-02J&LTech, Korea)was used to carry out friction and wear test. The tribological characteristics of the exoskeleton were investigated. Meanwhile, the wear morphology of the wear marks was observed by field emission scanning electron microscopy. The test result showed that its head and chest exoskeleton contain abundant calcium, and most of them are present in a form of amorphous structure and with a small amount of calcium carbonate. The surface of head and chest exoskeleton had a concave and convex hull bristle microstructure. Its exoskeleton was composed of upper epidermis, outer epidermis and inner epidermis. The upper epidermis was made up of thin waxy layers. Calcium salt deposits and crustacean protein fibers constituted the outer and inner epidermis, and the outer epidermis and the inner epidermis were in the form of twistedplywood. The needle-like calcium salt was unevenly distributed in a spiral splint, similar to a bone structure. The hardness of the exoskeleton was 0.503 GPa and the elastic modulus was 18.019 GPa. The twistedplywood had good scalability. After the load was unloaded, the twistedplywood could be well restored. There were many abrasive grains in the furrow at the wear location of the specimen. This showed that the friction behavior is abrasive wear. The friction factor showed a leaping change, the minimum friction factor was less than 0.1, and the maximum value was around 0.8. Many pores were distributed over the calcium salt deposits and the twisted-plywood. The main function of these pores was to deliver nutrients. When the Si3N4 ceramic ball and the exoskeleton rubbed against each other, the continuous sliding friction behavior was interrupted and mitigated by these pores. As the sliding friction behavior continued, the chitin in the spiral plywood was quickly worn away. The needle-like calcium salt was exposed to the friction surface. A non-smooth characteristic of the wear surface geometry was formed on the friction interface. Small free abrasive particles couldeasily roll on the non-smooth surface with less resistance. Therefore, the friction was reduced and the friction factor showed a jumping change. This research can provide a bio-inspired basis for the innovative design of agricultural composite materials and anti-friction surface of soil-engaging components. In addition, the experiment data can provide theoretical basis for the study of the tribology properties of soil animal exoskeleton in the future by observing the microstructure and analyzing the friction properties.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Tribology
Controlled terms:Abrasives - Calcium carbonate - Deposits - Elastic moduli - Electron emission - Exoskeleton (Robotics) - Field emission - Field emission microscopes - Friction - Hardness - Microstructure - Needles - Nitrogen compounds - Plywood - Salt deposits - Salts - Scanning electron microscopy - Silicon compounds - Soil testing - Soils - Structural design - Wear of materials - Wood products - X ray spectrometers - X rays
Uncontrolled terms:Field emission scanning electron microscopy - Friction and wear - Friction and wear behaviors - Hardness and elastic modulus - Soil-engaging components - Tribological characteristics - X ray diffractometers - X-ray fluorescence spectrometer
Classification code:408.1 Structural Design, General - 483.1 Soils and Soil Mechanics - 505.1 Nonmetallic Mines - 606.1 Abrasive Materials - 741.3 Optical Devices and Systems - 804 Chemical Products Generally - 811.2 Wood and Wood Products - 931 Classical Physics; Quantum Theory; Relativity - 932.1 High Energy Physics - 951 Materials Science
Numerical data indexing:Pressure 1.80e+10Pa, Pressure 5.03e+08Pa
DOI:10.11975/j.issn.1002-6819.2018.07.007
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 19>
Accession number:20182405313554
Title:Ultrasonic nondestructive examination of intramuscular fat using ultrasonic for live Congjiang pig
Authors:Zhang, Xiong (1); Zhang, Yong (2); Shang, Yishun (1); Shi, Kaizhi (1); Zhang, Yongjun (3); Wang, Jing (1); Chen, Yi (3)
Author affiliation:(1) Institute of Guizhou Animal Husbandry and Veterinary Science, Guiyang; 550005, China; (2) Key Laboratory of Animal Genetics, Breeding and Reproduction in the Plateau Mountainous Region, Ministry of Education, College of Animal Science, Guizhou University, Guiyang; 550025, China; (3) College of Computer Science & Technology, Guizhou University, Guiyang; 550025, China
Corresponding author:Zhang, Yong(13618506188@139.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:187-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As one of the most important evaluating indicators of pork quality traits, the intramuscular fat (IMF) content has an influence on tenderness, flavor and succulence of the meat. Excessive and long-term selective breeding of high lean percentage and fast growth rate has resulted in generally lower IMF content in pigs. For traditional detection method, samples used for determination of IMF content usually come from slaughtering, which is difficult to operate and costs high. Congjiang pigs belongs to the characteristic local small breeds in China, and is well known for its small-sized body, slow growth, early sexual maturity, and low genetic diversity. The IMF percentage of Congjiang pigs reaches the domestic breeds standard level, but the population variation of IMF content is rather larger, with variation coefficient of 31.71%, suggesting efforts should be made to strengthen the breeding and improve group uniformity. The aim of the study was to predict the IMF percentage in longissimus muscle of live Congjiang pig using real-time ultrasound image. In this research, the body weight (BW), backfat thickness (BFT), loin muscle deepness (LMD) and two longitudinal real-time ultrasound images were collected across the 10th to 11th rib and 5 cm off-midline on live pigs from 110 Congjiang pigs. 31 candidate image parameters of gray gradient and 4 direction (0, 45, 90, 135 angle) graylevel cooccurrence matrix within a defined region (50*50 pixel region) located at the center of longissimus muscle across the 10th to 11th rib for each ultrasound image were obtained using image analysis software (Matlab R2015b). After slaughter, a slice of longissimus muscle from left carcass across the 10th to 11th rib was cut off immediately for determining the IMF percentage by the petroleum ether extraction method. Each test was repeated three times, the mean value as the final IMF content. The model to predict longissimus muscle IMF percentage was developed using multivariate linear regression analysis with carcass longissimus muscle IMF percentage as dependent variables and BW, BFT, LMD and image parameters as independent variables. 42 Congjiang pigs were anew chosen for model validation by linear regression and correlation analysis of measured IMF and predicting IMF percentage. The result of regression analysis indicated that three independent variables which contained BFT and two image parameters of average gray (H6) and gradient entropy (H12) were significant in last model (P<0.05). The predictive equation is PIMF=6.443+0.064BFT+0.031H6-7.421H12, with determinate coefficient R<sup>2</sup>of 0.369. The determinate coefficient R<sup>2</sup>between the predictive value obtained by model and measured value of the validation set was 0.381. The root mean square error between predictive value and measured value of the validation set was 0.686. Correlation analysis showed that the pearson correlation coefficients and spearman correlation coefficients were 0.592 and 0.640 (P<0.001), respectively. Therefore, the regression model constructed in this study could be used to predict the living body of Congjiang pigs. Meanwhile, the experimental model provides a more convenient and effective nondestructive detection method for breeding with high IMF percentage of Congjiang pigs, which can reduce the breeding cost and shorten the breeding process, and promote the development of miniature pig's characteristic industry.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Ultrasonic testing
Controlled terms:Correlation methods - Forecasting - Image analysis - Mammals - MATLAB - Mean square error - Models - Muscle - Nondestructive examination - Regression analysis - Ultrasonic imaging
Uncontrolled terms:Breeding - Congjiang pigs - Gray level co-occurrence matrix - Intramuscular fats - Multivariate linear regression analysis - Nondestructive detection method - Pearson correlation coefficients - Spearman correlation coefficients
Classification code:461.2 Biological Materials and Tissue Engineering - 753.3 Ultrasonic Applications - 921 Mathematics - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 3.17e+01%, Size 5.00e-02m
DOI:10.11975/j.issn.1002-6819.2018.07.024
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 20>
Accession number:20182405313549
Title:Suitability assessment of P-M model by measuring ET<inf>0</inf>of turfs in Beijing, China
Authors:Yuan, Xiaohuan (1); Teng, Wenjun (1); Zhang, Hui (1); Wu, Juying (1); Yang, Xuejun (1)
Author affiliation:(1) Beijing Research & Development Center for Grass and Environment, Key Laboratory of Urban Agriculture (North China), Ministry of Agriculture, Beijing; 100097, China
Corresponding author:Wu, Juying(wujuying1@263.net)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:147-154
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Reference evapotranspiration (ET<inf>0</inf>) is an important parameter for agricultural irrigation scheme. Penman-Monteith (P-M) model is used extensively to simulate ET<inf>0</inf>for its accuracy in Europe and America area. But it's rarely evaluated by lysimeter measurement in China. This study aimed to: 1) reveal ET<inf>0</inf>characteristics in Beijing area; 2) evaluate the accuracy of P-M model under different weathers and at different scales; 3) research the effect of plant species on ET<inf>0</inf>measurement and P-M model evaluation. The evapotranspiration of the cool-season grass Festuca arundinacea, the warm-season grass Buchloe dactyloides, and the native species Carex leucochlora during the growing seasons of 2012-2014 was measured by lysimeters. Meteorological parameters of the solar radiation, the temperature, the air relative humidity, and the wind speed were measured using a weather station and were put into P-M model to obtain ET<inf>0</inf>values. Comparison was conducted between the P-M calculated ET<inf>0</inf>and the measured values under different weather conditions and at different scales. The consistency was analyzed using the statistical parameters of the slope and the coefficient of determination (R<sup>2</sup>) of the linear regression, the root mean square error (RMSE), and the concordance index (d). The results indicated that the calculated ET<inf>0</inf>showed consistent trends with the measured values at all the daily, weekly, and monthly scales. The peak of the monthly ET<inf>0</inf>came in May, with the values of 4.18±0.27 (P-M), 4.43±0.98 (F. arundinacea), 3.96±0.23 (C. leucochlora), 3.53±0.25 mm/d (B. dactyloides). October had the lowest value. The monthly calculated ET<inf>0</inf>showed a significant linear relationship with the solar radiation, the average air temperature, and the highest air temperature (P<0.01). The regression between ET<inf>0</inf>and the solar radiation had the highest R<sup>2</sup>of 0.885. The ratio of the calculated ET<inf>0</inf>to the measured value varied with different weathers. It increased with the solar radiation decreasing from the sunny to the rainy day. The P-M model overestimated ET<inf>0</inf>under overcast and rainy weathers. The RMSE and d between the P-M calculated ET<inf>0</inf>and the measured values increased with the assessment scale decreasing. The measured ET<inf>0</inf>differed significantly, sorted by F. arundinacea > C. leucochlora > B. dactyloides. The calculated ET<inf>0</inf>was the highest consistent with the measured value of F. arundinacea, with the regression slope of 0.99-1.03, the lowest RMSE of 0.62-1.05 mm/d, and the highest d of 0.89-0.90. It's concluded that P-M model was applicable for Beijing area. But it could overestimate ET<inf>0</inf>under overcast and rainy weathers or in cold spring.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Atmospheric temperature
Controlled terms:Evapotranspiration - Lysimeters - Mean square error - Models - Regression analysis - Soil surveys - Solar radiation - Wind
Uncontrolled terms:Agricultural irrigation - Buchloe dactyloides - Carex leucochlora - Coefficient of determination - Festuca arundinacea - Meteorological parameters - Reference evapotranspiration - Turf
Classification code:443.1 Atmospheric Properties - 483.1 Soils and Soil Mechanics - 657.1 Solar Energy and Phenomena - 922.2 Mathematical Statistics - 943.3 Special Purpose Instruments
DOI:10.11975/j.issn.1002-6819.2018.07.019
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 21>
Accession number:20182405313557
Title:Evaluation of environmental quality for organic production areas in ecological animal husbandry of Sanjiangyuan
Authors:Shi, Wenjiao (1, 2, 4); Wang, Zong (1, 3, 4); Wu, Xi (1, 5)
Author affiliation:(1) Key Laboratory of Land Surface Pattern and Simulation, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing; 100101, China; (2) Key Laboratory of Carrying Capacity Assessment for Resource and Environment, Ministry of Land and Resources, Beijing; 101149, China; (3) State Key Laboratory of Resources and Environment Information System, Institute of Geographic Sciences and Natural Resources Research, CAS, Beijing; 100101, China; (4) College of Resources and Environment, University of Chinese Academy of Sciences, Beijing; 100049, China; (5) College of Geodesy and Geomatics, Shandong University of Science and Technology, Qingdao; 266590, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:209-217
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Sanjiangyuan area, which is known as "China's water tower", is an important base for organic animal products in China, and plays an important role in protection of ecological environment. Thus we urgently need to carry out the environmental quality evaluation for organic producing areas in the typical areas of the project called "Construction of Smart Platform for Ecological Animal Husbandry in Sanjiangyuan". We selected 11 typical demonstration villages as the study area to cover the whole planning area. The soil, water and air samples were collected from each demonstration village. Then, we comprehensively evaluated the quality of soil, water and atmospheric environment in the study area by individual and integrated pollution indices based on the grading standards of the pollution indices. Moreover, we classified soil fertility, water quality and atmospheric environment quality according to the different classification of quality indices. The results showed that all of the average pollution indices of soil, water and atmospheric environment quality in the 11 demonstration villages were less than 1, and the attainment rate of each monitored item in the demonstration villages was as high as 100%. The average integrated pollution indices of soil, water environment quality and air quality were 0.356, 0.235 and 0.270, respectively, and all of those reached the cleaning level according to the index grading standards of integrated pollution. For soil environmental quality, the pollution index of Ni, almost reaching half of the standard, was the highest one in all of the soil pollution indices. For water environmental quality, the pollution indiex for the average of monitoring indiex in the study area were between 0.001 and 0.330, and the pollution index of the average content of Hg in the demonstration villages reached 0.330 due to the highest value of 1.860 in Guomaying Village. For the atmospheric environment quality, the integrated pollution indices in the study area were between 0.083 and 0.468. In addition, the average of soil organic matter reached 86 g/kg, which was 4 times higher than that of standard value. Thus the soil fertility was at the first level in all 11 demonstration villages according to the classification standard of soil fertility. Water quality level reached the first level (except Hg) in the study area according to the classification standard of environmental quality of surface water. The atmospheric environment quality of the study area was excellent and the grade was above the second level. Nearly half of the number of days is up to the first level based on the classification of index of atmospheric environment quality. In summary, according to the grading standard of integrated pollution index, the environmental quality of the planning demonstration area for the second phase of ecological protection and construction in Sanjiangyuan has reached a clean level, and the environmental quality meets the environmental quality requirements of Specification for Field Environmental Investigation, Monitoring and Assessment of Green Food (NY/T 1054-2013) and Organic Products (GB/T 19630.1-2011). Thus, the study area is very suitable for the development of organic, green industry. This study can provide scientific basis for organic animal husbandry production and environmental quality certification in Sanjiangyuan area.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Quality control
Controlled terms:Agriculture - Air - Air cleaners - Air quality - Animals - Demonstrations - Environmental protection - Grading - Pollution detection - River pollution - Rural areas - Soil pollution - Soils - Surface waters - Water quality - Water towers
Uncontrolled terms:Atmospheric environment - Ecological environments - Environmental investigation - Environmental quality - Integrated pollution indices - Monitoring and assessment - Organic products - Sanjiangyuan area
Classification code:444.1 Surface Water - 445.2 Water Analysis - 446.1 Water Supply Systems - 451.2 Air Pollution Control - 453 Water Pollution - 454.2 Environmental Impact and Protection - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.3 Quality Assurance and Control
Numerical data indexing:Percentage 1.00e+02%
DOI:10.11975/j.issn.1002-6819.2018.07.027
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 22>
Accession number:20182405313551
Title:Requirement of revisiting period, spatial resolution and spectrum of satellite for grain-soybean rotations monitoring
Authors:Liu, Jia (1); Wang, Limin (1); Yang, Fugang (1); Yang, Lingbo (1); Ji, Fuhua (1)
Author affiliation:(1) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing; 100081, China
Corresponding author:Wang, Limin(wanglimin01@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:165-172
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Examination on effect of cereal-soybean rotation is a major business content of agriculture remote sensing monitoring, and the remote sensing data indices are also required for optical satellite development. To meet the requirement on remote sensing monitoring of cereal-soybean rotation, and specially to meet the requirements on the minimal monitoring land parcel, crop types and timeliness, the paper particularly analyzed 3 indices of optical remote sensing satellites: spatial, spectral, and temporal resolutions, and thus provided a theoretical basis for the load design of remote sensing satellites. In setting of spatial resolution, a bulk of arable land was taken as the minimum resolution unit. Based on UAV (unmanned aerial vehicle) images with the resolution of 0.1 m, the paper analyzed the effect of reducing resolution on the visual observation identification capacity on the bulk of arable land by gradually reducing the spatial resolution. In optional spectrum setting, by taking corn and soybean as the major crops of cereal and bean, based on Rapideye images with the spatial resolution of 5 m, and Landsat-OLI images with the spatial resolution of 30 m, the study analyzed the identification capacity on corn and soybean under the combinations of 4 basic wavebands (blue, green, red, and near infrared) and red edge, as well as the combinations of basic wavebands and short wave. In satellite revisiting period setting, the calculation was based on the highest cloud cover frequency of Sichuan Basin of 70%, and the shorter soybean growth period of 90 d. By dividing crop growth stage into 3 periods, i.e. early, middle, and late periods, taking one month as a growth period, the study took 3 clear sky images for each month as the indices to analyze the requirement on the minimum revisiting period of the satellite. The result shows that, to meet the demand of remote sensing examination of crop rotation nationwide, the ideal spatial resolution of remote sensing data shall be better than 0.3 m. By taking spectral setting of basic wavebands (blue, green, red and near infrared) + red edge, or basic wavebands (blue, green, red, and near infrared) + short waveband, the revisiting period has reached 1 time every 3 days. By meeting the above conditions, we can make effective identification on the bulk of arable land with the width of 0.3 m, which is common in China, so as to achieve the target of land identification. It can also achieve the object of identifying the major crop rotation types through effective identification of corns and soybeans in middle growth period by making use of the difference of the spectrum characteristics of red edge and short wave of different crops. High revisiting frequency is used to ensure the acquisition of clear sky images with the 3 periods of acquisition capacity, which not only ensures the acquisition of the images of sensitive periods, but also ensures the acquisition of the image of early periods and later periods. And it can improve the efficiency and accuracy of crop type identification, and thus improve the efficiency of automatic operation on the targets of cereal-bean rotation. The requirement analysis on optical satellite indices in this paper is proposed only for the remote sensing monitoring of cereal-soybean rotation programs. As to whether implement this index or not during the actual design of satellite loads, the satellite load capacity, costs, and the supplement capability of other remote sensing data should be considered, as well as the monitoring demands of other agriculture programs. Proposing a relatively universal satellite design index can lay a foundation for the development of the agriculture remote sensing satellite system.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:51
Main heading:Remote sensing
Controlled terms:Antennas - Communication satellites - Crops - Efficiency - Image acquisition - Image analysis - Image resolution - Infrared devices - Land use - Monitoring - Rotation - Satellites - Unmanned aerial vehicles (UAV) - Verification
Uncontrolled terms:China - High resolution - Identification capacities - Remote sensing monitoring - Remote sensing satellites - Satellite images - Spectrum characteristic - UAV (unmanned aerial vehicle)
Classification code:403 Urban and Regional Planning and Development - 652.1 Aircraft, General - 655.2 Satellites - 655.2.1 Communication Satellites - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723 Computer Software, Data Handling and Applications - 821.4 Agricultural Products - 913.1 Production Engineering - 931.1 Mechanics
Numerical data indexing:Age 8.22e-03yr, Percentage 7.00e+01%, Size 1.00e-01m, Size 3.00e+01m, Size 3.00e-01m, Size 5.00e+00m
DOI:10.11975/j.issn.1002-6819.2018.07.021
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 23>
Accession number:20182405313548
Title:Effect of alternate wetting and drying irrigation and nitrogen coupling on endogenous hormones, nitrogen utilization
Authors:Xu, Guowei (1, 2); Lu, Dake (1); Liu, Congjie (1); Wang, Hezheng (1); Chen, Mingcan (1); Li, Youjun (1)
Author affiliation:(1) Agricultural College, Henan University of Science and Technology, Luoyang; 471003, China; (2) Key Laboratory of Crop Genetics and Physiology of Jiangsu Province, Yangzhou University, Yangzhou; 225009, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:137-146
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil moisture and nitrogen nutrient are the main factors affecting rice (Oryza sativa L.) production.Grainyield of rice has steadily increased worldwide in the past years, partly owing to the enhancement in nutrient inputs from fertilizer, especially nitrogen fertilizer application. Irrigationof alternate wetting and dryingis an effective water-saving irrigation technique, which has provided idealeconomic and ecological benefits. It is widely applied in major rice-producing countries in Asia, suchas China, Philippines, Vietnam, India, and Bangladesh. The inefficient use of freshwater and nitrogen resources is a major problem in rice production in China. Thus, it is significant to improve the efficiency of water and fertilizer resourcesutilization in agricultural production.In order to investigate the effects of irrigationof alternate wetting and drying and nitrogen coupling on endogenous hormones in root, nitrogen utilization and coupling effect, a soil-grown experiment with mid-season japonica rice cultivar of Lianjing 7was conducted in 2015 and 2016 with 3 nitrogen application rates, namely, 0 (no nitrogen applied), 240 (normal amount, MN), and 360 kg/ha(high amount), and 3 irrigation regimes, namely, submerged irrigation (0 kPa), alternate wetting and moderate drying (-20 kPa), and alternate wetting and severe drying (-40 kPa). Our data revealed a significant interaction between irrigation regimes and nitrogen applications, with a similar result in 2015 and 2016. Under the same nitrogen levels, alternate wetting and moderate drying promoted the contents of Z+ZRand IAA in roots, which were significantly enhanced by 8.7% and 13.5% at heading stage respectively, and also increased the activities of NR (nitrate reductase), GS (glutamine synthetase) and GOGAT in leaves at main growth stages in comparison with submerged irrigation;and meanwhile nitrogen absorption and utilization was increased significantly, N accumulation under the MN and HN treatments was significantly enhanced by 144.3% and 164.0% at heading stage respectively, when compared with no nitrogen. By contrast, alternate wetting and severe drying inhibited Z+ZRand IAA contents in root, whichwere significantly reduced by 25.1% and 27.9% at heading stage respectively, and depressedNR, GS and GOGAT activity in leaves and nitrogen accumulation;and meanwhile nitrogen use efficiency decreased remarkably, and recovery efficiency, agronomic efficiency and partial factor productivity of nitrogen fertilizer decreased by 51.2%, 63% and 36.5% respectively, while the ABA content in roots increased significantly, and consistent performance could be observed at the different growth stages. MN treatment significantly increased the nitrogen use efficiency, and recovery efficiency, agronomic efficiency and partial factor productivity of nitrogen fertilizer were 52.6%, 15.3 kg/kg and 43.5kg/kg under the alternate wetting and moderate dryingrespectively. Under the same irrigation regime, the contents of Z+ZRand IAA in roots and nitrogen metabolism enzyme in leaves were increased with nitrogen application under submerged irrigation and irrigation of alternate wetting and moderate drying, while promoted firstly and then reduced under alternate wetting and severe drying. MN treatment obviously increased nitrogen use efficiency, which indicated that heavy nitrogen application decreased nitrogen utilization efficiency. Correlation analysis indicated that there was significant or extremely significant positive correlation between the content of Z+ZRand IAA in roots, nitrogen metabolism enzyme activity in leaves and nitrogen use efficiency, while remarkably negative correlation was found between ABA content in roots and nitrogen utilization efficiency. Nitrogen effect was positive in Z+ZRand IAA content in roots, nitrogen metabolism enzyme activity in leaves, and water supply and interaction effects were positive under alternate wetting and moderate drying after heading stage, while negative effect was found under alternate wetting and severe drying after heading stage. This study will explore the mechanism of water-nitrogeninteraction, which will provide theoretical and scientific evidence for the rice cultivation of high yield and high efficiency.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:48
Main heading:Nitrogen fertilizers
Controlled terms:Agronomy - Amino acids - Crops - Cultivation - Drying - Efficiency - Endocrinology - Enzyme activity - Grain (agricultural product) - Hormones - Irrigation - Metabolism - Nitrogen - Nutrients - Physiology - Productivity - Soil moisture - Underwater soils - Water conservation - Water supply - Wetting
Uncontrolled terms:Different growth stages - Endogenous hormones - Nitrogen application rates - Nitrogen metabolism - Nitrogen utilization efficiencies - Partial factor productivity - Rice - WETTING AND DRYING
Classification code:444 Water Resources - 446.1 Water Supply Systems - 461 Bioengineering and Biology - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.3 Agricultural Methods - 821.4 Agricultural Products - 913.1 Production Engineering
Numerical data indexing:Percentage 1.35e+01%, Percentage 1.44e+02%, Percentage 1.64e+02%, Percentage 2.51e+01%, Percentage 2.79e+01%, Percentage 3.65e+01%, Percentage 5.12e+01%, Percentage 5.26e+01%, Percentage 6.30e+01%, Percentage 8.70e+00%, Pressure -2.00e+04Pa, Pressure -4.00e+04Pa, Pressure 0.00e+00Pa
DOI:10.11975/j.issn.1002-6819.2018.07.018
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 24>
Accession number:20182405313538
Title:Noise sources identification and noise reduction methods of hammer mill
Authors:Cao, Liying (1); Yang, Zuowen (1); Jiao, Wei (2); Zhang, Yubao (1); Zhang, Yuepeng (1); Zhang, Hongyu (1)
Author affiliation:(1) Mechanical Engineering School, Inner Mongolia Science & Technology University, Baotou; 014010, China; (2) Institute of grassland research of CAAS, Hohhot; 010010, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:59-65
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to solve the problem of big noise during the working process of the hammer mill, and search for the main noise source and noise reduction method of hammer mill, the noise signals were collected and analyzed by the virtual instrument software LabVIEW and bench test on the hammer mill. The sound pressure level of the hammer mill was tested and analyzed in no-load and load conditions, and the spectrum of the hammer mill was tested. The result of this test shows the no-load sound pressure level of the hammer mill is bigger than the load sound pressure level. The material loading or not only changes the size of the peak of the noise. Thus it can be seen the key of absorbing the noise is to reduce the no-load aeromechanic noise. The noise sources of hammer mill were superimposed, bringing about the multivariate source coupling problem. The distribution operation method was used to test the noise of the hammer, screen, feeding inlet and feeding outlet. Sound pressure level and frequency spectrum were analyzed to find the main noise sources of the hammer mill, according to the main factors of noise such as the hammers, screen, feeding inlet and feeding outlet. Noise pressure level was tested and spectrum was analyzed in the state of noise with a single factor and combination of multiple factors. The results are as follows: The noise signals contain 47, 180, 200, 361, 893 and 1263 Hz. The screen, feeding inlet and outlet have no effect on the main frequency component. The screen has the noise reduction function; the feeding inlet and outlet enhance the noise pressure in different degrees. The sound pressure level of the single rotor is very small, which reveals that the hammer has a great influence on the noise. The noise is strengthened when the hammer and the outlet work together; the noise of hammer mill is greatly reduced when it has no hammer piece. Based on the analysis of no-load noise spectrum of 2400-2800 r/min, when the speed increases, the noise amplitude increases dramatically, indicating that the effect of noise on high-speed grinder is evident. When the speed is 2400-2800 r/min, the main noise source is in good agreement with the noise base frequency and the second-harmonic frequency of the hammer mill; when the speed is lower than 2600 r/min, the broadband signal energy to noise frequency signal of grinder is larger, indicating mill noise of vortex at low speed is dominant; when the speed is higher than 2600 r/min, the discrete signal energy to noise frequency signal of hammer mill is larger, that is to say the rotating noise is dominant at high speed. In the working condition of no load and rated speed, the noise sound pressure level of the hammer mill was tested with no hammer, single row hammer, 2 row hammers, 3 row hammers and 4 row hammers respectively. It is known that the number of hammers only affects the amplitude of the noise and has little influence on the change of the main frequency by analyzing the spectrum diagram of the no-load noise with different numbers of hammer pieces. Besides, the structure of feeding inlet, outlet and screen was improved in design. Taking the outlet improvement design as an example, turbulent kinetic energy of original and improved separation device was simulated. The comparison results show that the kinetic energy of the improved outlet is less. It is proved that the improvement of the outlet is beneficial to the noise reduction in the experiment, the total sound pressure level was reduced by 3 dB(A), the sound pressure levels of test points were reduced by 1.9-3.6 dB(A), and the hammer mill production was not greatly affected. Some other methods of noise reduction were proposed. This research provides theoretical evidence for the noise reduction design of the hammer mill.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Acoustic noise
Controlled terms:Acoustic variables measurement - Acoustic wave transmission - Agricultural machinery - Computer programming languages - Feeding - Fire alarm systems - Grinding mills - Hammers - Kinetic energy - Kinetics - Mechanization - Metal drawing - Noise abatement - Processing - Software testing - Speed
Uncontrolled terms:Distribution operations - Frequency - Hammermills - Noise - Noise reduction methods - Noise sources identification - Turbulent kinetic energy - Virtual instrument software
Classification code:535.2 Metal Forming - 601 Mechanical Design - 605.2 Small Tools, Unpowered - 691.2 Materials Handling Methods - 723.1.1 Computer Programming Languages - 723.5 Computer Applications - 751.1 Acoustic Waves - 751.4 Acoustic Noise - 821.1 Agricultural Machinery and Equipment - 913.4 Manufacturing - 914.2 Fires and Fire Protection - 931 Classical Physics; Quantum Theory; Relativity - 941.2 Acoustic Variables Measurements
Numerical data indexing:Frequency 1.26e+03Hz, Frequency 8.93e+02Hz, Rotational_Speed 2.40e+03RPM to 2.80e+03RPM, Rotational_Speed 2.60e+03RPM
DOI:10.11975/j.issn.1002-6819.2018.07.008
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 25>
Accession number:20182405313552
Title:Immature mango detection based on improved YOLOv2
Authors:Xue, Yueju (1, 2, 3, 4); Huang, Ning (1, 2); Tu, Shuqin (5); Mao, Liang (1); Yang, Aqing (1); Zhu, Xunmu (1); Yang, Xiaofan (1); Chen, Pengfei (1)
Author affiliation:(1) College of Electronic Engineering, South China Agricultural University, Guangzhou; 510642, China; (2) Guangdong Engineering Research Center for Datamation of Modern Pig Production, Guangzhou; 510642, China; (3) Guangdong Modern Agricultural Science and Technology Innovation Center for Intelligent Orchard, Guangzhou; 510642, China; (4) Guangdong Engineering Research Center for Information Monitoring in Agriculture, Guangzhou; 510642, China; (5) College of Mathematics and Informatics, South China Agricultural University, Guangzhou; 510642, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:173-179
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Automatic target detection of immature mangoes on the trees is one of the key steps of early estimation or intelligent spraying of mangoes. In orchard scenes, it is extremely difficult to detect immature mangoes because of variability of light, complex background and high color similarity between mangoes and leaves. Especially, detection of occluded and overlapped mangoes is a challenging task. An immature mango detection model based on improved YOLOv2 with high speed and accuracy was proposed. By introducing dense connectivity pattern into Tiny-yolo, Tiny-yolo network with dense blocks (Tiny-yolo-dense) was designed. And the dense block was used to replace the 7th convolutional layer with low-resolution feature map in Tiny-yolo to avoid adding more extra computational complexity. In the dense block, each layer receives the feature-maps of all preceding layers and passes on its own feature-map to all subsequent layers, which improves flow of information, and encourages feature reuse and multi-level features fusion. To overcome the difficulty of occluded or overlapped mango detection, foreground region samples of occluded or overlapped fruits were manually labeled, and then the foreground region samples were used to train YOLOv2 model. Feature extraction only for foreground region can avoid extracting redundant feature of non-target region in bounding box, which can enhance feature learning from foreground region of occluded or overlapped fruits. The steps of our work were stated as follows: Firstly, to reduce the influence of natural lighting variations on mango images, adaptive histogram equalization was used to improve the quality of training sample images and the variety of illumination. And foreground region and bounding box of training samples were manually labeled. The original training set including 3 702 bounding box labels of all mango targets and 1 077 foreground region labels of occluded or overlapped fruits from 660 images was constructed, and testing set for model validation including 1 713 bounding box labels of mango targets from other 300 images was also set up. In addition, training data size was augmented by horizontal flipping and multi-angle rotating according to the variety of suspension postures of mangoes. Image rotation with angles of ±10° and ±20° was used for data augmentation. And then, Tiny-yolo-dense was applied as a basic network to design the improved YOLOv2 for the mango detection. Moreover, by higher resolution inputs and multi-scale strategy, foreground region and bounding box of training samples were used to train improved YOLOv2 network. Every 10 batches, the present training scale was exchanged randomly by another one before continuing training. In this paper, input scale of 512×512 and training scales of {384, 416&mellip;672} were selected. Lastly, the trained networks were used to detect mango on testing set. The experimental results showed that the proposed algorithm had better performance for mango detection in natural scenes. At a detection rate of 83 fps, the precision rate reached up to 97.02%, and the recall rate reached up to 95.10%. Our algorithm was 11 times faster than the Faster RCNN(circular convolutional neural network), and achieved better detection performance in condition of complex scenes with occlusion and overlapping of mangoes. Moreover, our method also significantly outperforms YOLOv2 and Adaboost classifier based on HOG(histogram of oriented gradient) features. Our work provides an effective method to quickly detect mango under orchard scenes.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Feature extraction
Controlled terms:Adaptive boosting - Complex networks - Convolution - Estimation - Extraction - Fruits - Graphic methods - Image enhancement - Magnetic levitation vehicles - Neural networks - Object recognition - Orchards - Sampling - Target tracking
Uncontrolled terms:Ada boost classifiers - Adaptive histogram equalization - Automatic target detection - Connectivity pattern - Convolutional neural network - Detection performance - Histogram of oriented gradients - Mango
Classification code:716.1 Information Theory and Signal Processing - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 802.3 Chemical Operations - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics
Numerical data indexing:Percentage 9.51e+01%, Percentage 9.70e+01%
DOI:10.11975/j.issn.1002-6819.2018.07.022
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 26>
Accession number:20182405313553
Title:EGCG distribution visualization in tea leaves based on hyperspectral imaging technology
Authors:Li, Xiaoli (1); Wei, Yuzhen (1); Xu, Jie (2); Zhao, Zhangfeng (3); Zhong, Jiang (3); He, Yong (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou; 310058, China; (2) College of Biological Chemical Science and Engineering, Jiaxing University, Jiaxing; 314001, China; (3) College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou; 310014, China
Corresponding author:He, Yong(yhe@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:180-186
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:EGCG (epigallocatechin gallate) is an important functional material in tea, and it is regarded as an indispensable index for evaluating the quality of tea as it's of great benefit to health. With the difference of tea varieties and physiological parts of tea plant, the distribution of EGCG is different. Visualization of EGCG distribution contributes to analyze the distribution and metabolism of EGCG directly. However, no research on the visualization of EGCG distribution in tea leaves has been reported till now. This study took advantage of hyperspectral imaging technology and chemometrics method to realize visualization of EGCG distribution in fresh tea leaves. On the basis of visualization, distribution characteristics of EGCG between different tea varieties and different leaf positions were studied. The operation procedure of visualization was mainly divided into 5 steps: 1) Acquisition of physical and chemical information. To obtain the physical information, 486 fresh leaves from the 1st to the 6th leaf positions at the tender shoots of tea plants with 3 varieties were gathered first, hyperspectral images of these fresh leaves were collected by a hyperspectral imager, and then average spectral information used to build models was extracted from the hyperspectral images. To acquire the chemical information, the fresh leaves were freeze-dried, ground into powder, sieved and heated by water-bath to obtain the EGCG solution, and the EGCG concentration was determined through HPLC (high performance liquid chromatography) at last. 2) Samples division and spectral preprocessing. In order to divide the samples reasonably, an interval-extraction method was adopted to ensure the distribution uniformity of chemical values. All the samples were divided into calibration set and prediction set in a ratio of 2: 1. Due to the limited performance of hyperspectral imager, obvious noise region of the spectra was eliminated first in order to avoid the interference to subsequent analysis. For 2 common issues during spectral acquisition, i.e. random noise and baseline drift, the SG (Savitzky-Golay) smoothing and baseline correction were performed. Through comparing different preprocessing methods, it was found that the unprocessed spectra showed the best performance. 3) Model establishment and analysis based on full efficient spectra. To determine the best modeling method, PCR (principal component regression), PLSR (partial least squares regression), RBFNN (radial basis function neural network) and LS-SVR (least squares support vector regression) models between full efficient spectra and EGCG concentration values were established respectively. The results showed that the nonlinear models had better performance, and by comparing the evaluation parameters of different models, LS-SVR was chosen as the best modeling method. 4) Model establishment and analysis based on feature bands. The full efficient spectra contain 478 variables, which carry rich information, and cause a collinear problem between variables at the same time. To reduce the data redundancy and the complexity of the model based on full efficient spectra, SPA (successive projection algorithm) was employed to select feature bands, and the LS-SVR model based on feature bands showed better performance compared with the LS-SVR model based on full efficient spectra, with the R<inf>p</inf><sup>2</sup>(determination coefficient of prediction set) and RPD (residual prediction deviation) that is the ratio of standard deviation of measured values to root mean square error of prediction set reaching 0.905 and 3.248 respectively. 5) Generation of EGCG distribution map. Inputting the feature bands of each pixel selected by SPA in the testing hyperspectral images into the SPA-LS-SVR model, the EGCG concentration of each pixel could be calculated, so the distribution maps of EGCG in fresh tea leaves were generated finally. This study proved that EGCG distribution visualization in fresh tea leaves can be realized by hyperspectral imaging technology and chemometrics method. Through the analysis of EGCG distribution between different tea varieties and different leaf positions, the distribution showed significant differences. This study provides an effective method for cultivation of tea plant variety with high EGCG concentration, analysis on the metabolism rule of EGCG and recognition of tea shoots.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Hyperspectral imaging
Controlled terms:Crops - Extraction - Forecasting - Functional materials - High performance liquid chromatography - Image analysis - Image processing - Least squares approximations - Mean square error - Metabolism - Models - Physiology - Pixels - Plants (botany) - Principal component analysis - Radial basis function networks - Regression analysis - Spectroscopy - Visualization
Uncontrolled terms:EGCG - Hyperspectral imaging technologies - Least squares support vector regression - Partial least squares regression - Rbfnn(radial basis function neural network) - Root-mean-square error of predictions - Spetrum analysis - Successive projection algorithms
Classification code:461.9 Biology - 802.3 Chemical Operations - 821.4 Agricultural Products - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 951 Materials Science
DOI:10.11975/j.issn.1002-6819.2018.07.023
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 27>
Accession number:20182405313540
Title:Experiments on collaborative control characteristics of driving and steering for agricultural flexible chassis based on PWM signal
Authors:Qu, Jiwei (1); Guo, Kangquan (1, 2); Gao, Hua (1); Song, Shujie (3); Li, Yining (1); Zhou, Wei (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; 712100, China; (2) Shaanxi Engineering Research Centre for Agriculture Equipment, Yangling; 712100, China; (3) College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an; 710119, China
Corresponding author:Guo, Kangquan(jdgkq@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:75-81
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Electromagnetic friction lock is an important part of agricultural flexible chassis. When it is closed, flexible chassis will be driven forward, and will steer when opened. In engineering practice, flexible chassis needs to steer while advancing. Therefore, there is conflict between the opening and the closing of electromagnetic friction lock when the 2 motions need to be carried out at the same time. In order to solve this problem, a method based on pulse width modulation (PWM) technology was proposed to control the opening and the closing in this paper. The opening was achieved during low level of PWM wave, while the closing was achieved during high level of PWM wave. In this way, flexible chassis can be driven forward during steering. Further, some experiments were conducted to investigate the influences of PWM frequency and duty cycle on driving and steering performance of flexible chassis. Firstly, based on off-centered steering shaft test bench, two-factor experiments were performed to study the effects of frequency and duty cycle on pulse tightening torque, using a traction device which was composed of a lever and a force sensor. Then tightening torque was calculated from force sensor measurement and arm length value. Secondly, for the purpose of examining the characteristics of time-sharing steering related with the influence of frequency, duty cycle and initial speed of electric wheel, a quadratic orthogonal regression experiment was conducted on off-centered steering shaft test bench. In this test, steering motion was simulated by controlling the speed of horizontal turntable of test bench and electric wheel. Average steering angular velocity was taken as the evaluating indicator of steering characteristics, and it can be attained by measuring the steering time due to the same target angle of steering. Afterwards, results of two-factor experiment showed that frequency, duty cycle and their interaction had highly significant influences on tightening torque (P<0.01). In the process of rotation, the curve of tightening torque showed a pulse change, and the rotation angle of steering arm displayed a step-like rise. When frequency was 4-24 Hz and duty cycle was 20%-80%, the tightening torque of off-centered steering shaft varied from 6.822 to 40.046 N·m. The tightening torque declined as frequency increased when duty cycle was 20%-80% except a few duty cycles. Meanwhile, for the frequency ranging from 4 to 24 Hz, tightening torque rose with the increasing of duty cycle. Then regression analysis was carried out according to the results and a regression model was presented. Results of quadratic orthogonal regression experiment illustrated that the average steering angular velocity was remarkably influenced by the PWM frequency, duty cycle and their interaction as well as the initial rotation speed of in-wheel motor (IWM) (P<0.05). With the increment of duty cycle and the initial speed of IWM, the steering average angular velocity decreased rapidly but slowly increased with the increasing of frequency. When the frequency was 4-24 Hz and the duty cycle was 20%-80%, and the initial speed of IWM was 30-120 r/min, the average steering angular velocity varied from 0 to 0.514 rad/s. Therefore, through changing the PWM frequency, duty cycle and the initial speed of IWM, the process of pulse-driven and time-sharing steering for flexible chassis is able to be well achieved, and these results can provide a basis for cooperative control of flexible chassis.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Pulse width modulation
Controlled terms:Agricultural machinery - Agriculture - Angular velocity - Chassis - Control engineering - Friction - Locks (fasteners) - Regression analysis - Torque - Transportation - Voltage control - Wheels
Uncontrolled terms:Co-operative control - Collaborative control - Engineering practices - Evaluating indicators - In-wheel motor (IWM) - Orthogonal regression - Steering characteristics - Steering shaft
Classification code:601.2 Machine Components - 662.4 Automobile and Smaller Vehicle Components - 731.3 Specific Variables Control - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 922.2 Mathematical Statistics - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Angular_Velocity 0.00e+00rad/s to 5.14e-01rad/s, Frequency 4.00e+00Hz to 2.40e+01Hz, Percentage 2.00e+01% to 8.00e+01%, Rotational_Speed 3.00e+01RPM to 1.20e+02RPM, Torque 6.82e+00N*m to 4.00e+01N*m
DOI:10.11975/j.issn.1002-6819.2018.07.010
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 28>
Accession number:20182405313561
Title:Method of improving classification accuracy of land cover based on time series NDVI database
Authors:Liao, Shunbao (1, 2); Yue, Yanlin (2)
Author affiliation:(1) College of Ecology and Environment, Institute of Disaster Prevention, Beijing; 101601, China; (2) College of Environment and Planning, Henan University, Kaifeng; 475004, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:241-248
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The most important task of carrying out the research on land use/land cover changes is to obtain accurate land cover data timely and efficiently. In recent years, many researches have been carried out to improve the accuracy of land cover classification, but they mainly focused on the aspects of land cover classification methods, classification features, classification systems and reducing noise pollution of remote sensing images. There were also some researches in which time series NDVI (normalized difference vegetation index) was directly applied to classify land cover or detect change of land cover. However, the researches that enhance classification accuracy for low classification precision areas on the basis of the existing land cover products using time series NDVI have not been found yet. In this paper, Henan Province in central China was taken as the study area, the regions possessing low classification precision with the existing MODIS land cover product (MOD12Q1) were selected, and the study on improving classification accuracy in these regions was carried out by means of the construction of time series NDVI database and the measurement of similarity of time series NDVI curves. The results are as follows: 1) Time series NDVI is an important feature for land cover classification, and there is a strong correlation between time series NDVI and land cover categories. The overall accuracy of the land cover data extracted based on time series MODIS-NDVI database in the study area was as high as 79.57% (sample evaluation based on field survey) and 73.45% (comparative evaluation with land use map at scale of 1: 100 000) respectively. It is demonstrated that it is feasible to improve the accuracy of land cover classification by means of time series NDVI. 2) It was shown from a practical application that classification accuracy of existing land cover products could be significantly improved by using time series MODIS-NDVI database. The overall classification accuracy of the new land cover product, which was obtained by revising original MCD12Q1 based on time series MODIS-NDVI database, increased by 10.29% (from 72.76% to 83.05%, comparative evaluation) and 17.20% (from 64.52% to 81.72%, sample evaluation) respectively. 3) Degree of accuracy improvement for various land cover categories was different. The producer's accuracy for forest land, grassland, cultivated land, artificial land surface and water body increased by 35.36%, 29.51%, 2.98%, 6.96% and 6.11% respectively. 4) With regard to 2 specific methods that were used for judging similarity of NDVI curves in time series, the minimum distance (MD) method is superior to spectral angle matching (SAM) method in general. In conclusions, it is an effective method of improving precision of existing land cover products to retain parts of land cover information with high precision and reclassify the parts with low precision using time series NDVI. The classification accuracy of land cover products can be significantly improved by revising them based on time series NDVI database.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Classification (of information)
Controlled terms:Database systems - Image enhancement - Land use - Noise pollution - Radiometers - Remote sensing - Time series - Vegetation
Uncontrolled terms:Accuracy - Classification precision - Comparative evaluations - Evaluation - Land cover - Land cover classification - Land use/land cover change - Normalized difference vegetation index
Classification code:403 Urban and Regional Planning and Development - 716.1 Information Theory and Signal Processing - 723.3 Database Systems - 751.4 Acoustic Noise - 922.2 Mathematical Statistics - 944.7 Radiation Measuring Instruments
Numerical data indexing:Percentage 1.03e+01%, Percentage 1.72e+01%, Percentage 2.95e+01%, Percentage 2.98e+00%, Percentage 3.54e+01%, Percentage 6.11e+00%, Percentage 6.45e+01% to 8.17e+01%, Percentage 6.96e+00%, Percentage 7.28e+01% to 8.30e+01%, Percentage 7.35e+01%, Percentage 7.96e+01%
DOI:10.11975/j.issn.1002-6819.2018.07.031
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 29>
Accession number:20182405313560
Title:Photoelectricity and photothermal performance experiment on solar photovoltaic/loop-heat-pipe water heating system
Authors:Li, Hong (1); Hou, Pingwei (1); Sun, Yue (1)
Author affiliation:(1) School of Civil Engineering and Mechanics, Yanshan University, Qinhuangdao; 066004, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:235-240
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The aim of this paper was to present a dedicated experimental investigation of the thermal and electrical performance of a solar photovoltaic/loop-heat-pipe water heating system. The studied system was the combination of the loop heat pipe and the solar photovoltaic/thermal technology, which was assisted by the electric water heater to product hot water for residential buildings in cold zone. The proposed system could work in 2 operational modes, and the operational modes were mainly determined by the variation of solar radiation. When solar radiation was high, the system operated in the photovoltaic/loop-heat-pipe mode; when solar radiation was low or it was a rainy day, the electric water heater was turned on to heat water to match the preset value. The experimental platform for the solar photovoltaic/loop-heat-pipe water heating system was built and a series of experiments under real weather conditions were conducted. Based on test results, energy and exergy performance of the studied system under typical working condition was analyzed. And the typical working conditions include the transitional season condition, the summer condition and the winter condition. Besides, energy and exergy performance of the system on the specific 2 days was discussed and compared. What was more, the impact of the refrigerant charge quantity on the operating performance was analyzed. Therefore, main content of this paper was composed of energy and exergy performance analyses under typical working conditions and selected full days. The experimental results in the photovoltaic/loop-heat-pipe mode were analyzed in terms of the solar thermal efficiency, the photovoltaic efficiency, the overall energy efficiency and the overall exergy efficiency. For the solar thermal efficiency and overall energy efficiency, the experimental results were the highest in summer, and the daily average values were 62.1% and 68.1% respectively. For the photovoltaic efficiency and overall exergy efficiency, the experimental results were the highest in winter, and the daily average values of them were 13.7% and 10.9% respectively. The whole system performance considered the performance of 2 operational modes, and therefore the overall energy and exergy efficiency of the whole system were a litter higher than those of the mode of photovoltaic/loop-heat-pipe. In this paper, the experimental results of April 20th and December 9th were chosen to analyze full-day performance of this system, and the solar thermal efficiency and overall energy efficiency were higher on April 20th, while the photovoltaic efficiency and overall exergy efficiency of full-day performance were higher on December 9th. This paper also discussed the system performance with different refrigerant charge quantities in similar ambient environment. And the results showed that 30% refrigerant charge quantity was conducive to the improvement of solar thermal efficiency and overall energy efficiency of this system and 40% refrigerant charge quantity was conducive to the improvement of electrical efficiency and overall exergy efficiency of this system.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Energy efficiency
Controlled terms:Exergy - Experiments - Heat pipes - Hot water distribution systems - Refrigerants - Solar concentrators - Solar energy - Solar heating - Solar power generation - Solar radiation - Water heaters
Uncontrolled terms:Electric water heaters - Electrical performance - Energy and exergy efficiency - Experimental investigations - Overall energy efficiency - Performance experiment - Photo-voltaic efficiency - Photovoltaic
Classification code:525.2 Energy Conservation - 615.2 Solar Power - 619.1 Pipe, Piping and Pipelines - 641.1 Thermodynamics - 657.1 Solar Energy and Phenomena - 803 Chemical Agents and Basic Industrial Chemicals - 901.3 Engineering Research
Numerical data indexing:Age 5.48e-03yr, Percentage 1.09e+01%, Percentage 1.37e+01%, Percentage 3.00e+01%, Percentage 4.00e+01%, Percentage 6.21e+01%, Percentage 6.81e+01%
DOI:10.11975/j.issn.1002-6819.2018.07.030
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 30>
Accession number:20182405313565
Title:Optimization of technical parameters for rice straw fiber-based mulch
Authors:Chen, Haitao (1); Zhu, Xiaoxin (1); Liu, Shuang (1)
Author affiliation:(1) Engineering College, Northeast Agricultural University, Harbin; 150030, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:271-279
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The long term use of farmland plastic mulching not only brings us economic benefit, but also brings the hidden danger of pollution. Residual film existing in the soil will affect the growth and development of crop root and the transfer of water-fertilizer, and meanwhile will lead to the crop yield reduction. By using rice straw as the main raw material, the straw fiber mulch can achieve green (organic) cultivation and scientific straw returning to the field, and reduce agricultural non-point source pollution effectively. However, the characteristics of increasing temperature in soil need to be further improved, since the fiber mulch is milky and transmittance is low, into which the infrared in the daytime sunlight less streamed, leading to plants and soil heat reduction. When there exists the difference between atmosphere and intramembranous temperature, the heat will dissipate if the temperature is high in the straw fiber film, which leads to the thermal insulation performance not ideal. In order to improve the deficiency of temperature increasing of straw fiber mulch, and make it have a better practicability to replace the plastic mulching in an all-round way, the technology parameters of staining the milky straw fiber mulch to green were studied, and the solar hot light transmittance was increased and the soil temperature loss was further reduced by adding environmental protection functional additive to decrease the air permeability of the fiber mulch. The five-factor and five-level quadratic regression orthogonal rotation center combined method was applied. Functional additive is added at a constant temperature of 60℃ for 45 min in the wet process of dyeing, and mixed thoroughly until it is completely combined, and the pH value of fiber pulp is controlled to be stable at 6.0. Using the wood pulp fibers to build skeleton, and adding rice straw fiber as the main filling material, supplemented by safe and environmental protection synthetic food dyes, such as lemon yellow and brilliant blue dye, the straw fiber pulp, dye addition, brilliant blue proportion, modifier addition and the mass fraction of wet strength agent as influence factors were studied, as well as the air permeability, dye uptake, fading rate, dry tensile strength and wet tensile strength as the performance evaluation indices. The optimal technology parameters of green straw fiber mulch were determined as follows: rice straw fiber pulp addition amount of 71%~79%, dye addition of 0.44%~0.53%, proportion of the brilliant blue of 90%, modifier addition of 0.6%, and the wet strength agent addition of 0.9%. Under such an optimized combination, we come up with a result in the evaluation of the indicators: The air permeability is lower than 2 µm/Pa·s, the dye uptake is higher than 80%, the fading rate is lower than 8%, the dry tensile strength is more than 40 N and the wet tensile strength is more than 16 N, which can meet the technical requirements of the cultivation of organic (green) crops field through covering the rice straw field mulch, and the hot light transmittance will increase and the air permeability will decrease, which will further improve the performance of heat preservation and moisture conservation.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Wood
Controlled terms:Air permeability - Atmospheric temperature - Crops - Cultivation - Dyeing - Environmental protection - Environmental technology - Fibers - Film growth - Moisture control - Optimization - Petroleum reservoir evaluation - Pollution - Pulp materials - Shotcreting - Soils - Straw - Tensile strength - Thermal insulation
Uncontrolled terms:Agricultural non-point source pollutions - Growth and development - Increasing temperatures - Insulation performance - Moisture conservation - Optimized combinations - Performance evaluation index - Technology parameters
Classification code:412 Concrete - 413.2 Heat Insulating Materials - 443.1 Atmospheric Properties - 454 Environmental Engineering - 454.2 Environmental Impact and Protection - 483.1 Soils and Soil Mechanics - 512.1.2 Petroleum Deposits : Development Operations - 731.3 Specific Variables Control - 811.2 Wood and Wood Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques - 931.2 Physical Properties of Gases, Liquids and Solids
Numerical data indexing:Force 1.60e+01N, Force 4.00e+01N, Percentage 6.00e-01%, Percentage 8.00e+00%, Percentage 8.00e+01%, Percentage 9.00e+01%, Percentage 9.00e-01%, Time 2.70e+03s
DOI:10.11975/j.issn.1002-6819.2018.07.035
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 31>
Accession number:20182405313568
Title:Analysis on correlation between change of moisture status and texture during processing of air-dried yak meat
Authors:Ma, Jibing (1); Zhang, Li (1); Wang, Yan (1); Cui, Wenbin (1); Wang, Huihui (1); Yu, Qunli (1); Liu, Xiaobo (1)
Author affiliation:(1) College of Food Science and Engineering, Gansu Agriculture University, Lanzhou; 730070, China
Corresponding author:Zhang, Li(zhanglwubd@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:294-300
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The objective of this paper was to research the law of moisture migration, and to investigate the correlation between moisture status and the histological structure and texture during the processing of dried yak meat. The semimembranosus of the healthy and disease-free male yaks when they were from 3 to 4-year-old under natural grazing was selected to remove the fascia and fat on its surface and cut into the strips with cross-section of 2 cm × 2 cm. At the same time, the meat was hung on the wire and kept a distance of 1-2 cm between 2 adjacent pieces of meat in a dark and naturally ventilated place in Xiahe County, Gannan Prefecture, Gansu Province. The temperature was from -10 to -15℃ and the relative humidity was from 50% to 75% there. The samples were collected to analyze the changes of indices during natural drying of 60 d. Moisture ratio of dried yak meat was analyzed by the direct drying. Moisture activity and moisture status were evaluated respectively using the water activity meter and the low field nuclear magnetic resonance (LF-NMR). The change of texture characteristics of dried yak meat was measured by texture analyzer and the histological structure of dried yak meat was observed by hematoxylin eosinstaining. The results showed, during the 60 days of drying, moisture ratio decreased by about 60.27%. The final water activity reached about 0.308 and decreased by about 66.73%. On the 30th day, the peak integral area, which is immobile water content, decreased by about 98.12%, and no peak appeared after 40 days. With the reduction of moisture ratio, myofibril cross-sectional area, muscle fiber diameter and distance between muscle fibers were significantly decreased (P<0.05) respectively by about 42.65%, 67.15% and 61.22%. The hardness, cohesiveness, gumminess and chewiness were significantly increased (P<0.05), and among them, the chewiness that best represents the taste of dried meat increased by 1 229.16 g. However, the springiness and resilience decreased significantly (P<0.05) during the whole process.The change of immobilized water shows a significant negative correlation with changes in hardness, cohesiveness, gumminess, and chewiness, and have a significant positive correlation with springiness and resilience. Moreover, the decrease in distance between muscle fibers, diameter of myofibers and cross-sectional area of myofibers was negatively correlated with changes in hardness, cohesiveness, gumminess, and chewiness significantly, but have a significant positive correlation with changes in springiness and resilience. It shows that the immobile water in yak meat expands and evaporates continuously. It causes the contraction and aggregation of the muscle fiber of yak meat, which leads to the change of its textural properties in the process of natural freezing and drying. The results can provide a reference for the mechanism understanding of moisture migration and product quality control in the processing process of traditionally dried yak meat.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Thermal processing (foods)
Controlled terms:Drying - Fibers - Hardness - Meats - Moisture - Muscle - Nuclear magnetic resonance - Quality control - Textures
Uncontrolled terms:Cross sectional area - Histological structure - Low field nuclear magnetic resonance (LF NMR) - Negative correlation - Positive correlations - Product quality control - Texture characteristics - Water activity meter
Classification code:461.2 Biological Materials and Tissue Engineering - 822.2 Food Processing Operations - 822.3 Food Products - 913.3 Quality Assurance and Control - 951 Materials Science
Numerical data indexing:Age 1.10e-01yr, Age 1.64e-01yr, Age 3.00e+00yr to 4.00e+00yr, Mass 2.29e-01kg, Percentage 4.26e+01%, Percentage 5.00e+01% to 7.50e+01%, Percentage 6.03e+01%, Percentage 6.12e+01%, Percentage 6.67e+01%, Percentage 6.72e+01%, Percentage 9.81e+01%, Size 1.00e-02m to 2.00e-02m, Size 2.00e-02m
DOI:10.11975/j.issn.1002-6819.2018.07.038
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 32>
Accession number:20182405313547
Title:Effect of controlled irrigation and drainage on water saving, nitrogen and phosphorus loss reduction with high yield in paddy field
Authors:Yu, Shuangen (1, 2); Li, Si (1, 2); Gao, Shikai (1, 2); Wang, Mei (1, 2); Meng, Jiajia (1, 3); Tang, Shuhai (4)
Author affiliation:(1) Key Laboratory of Efficient Irrigation-Drainage and Agricultural Soil-Water Environment in Southern China, Ministry of Education, Hohai University, Nanjing; 210098, China; (2) College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing; 210098, China; (3) Huaian Water Resources Bureau, Huai'an; 223001, China; (4) Lianshui Water Conservancy Research Institute, Huai'an; 223001, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:128-136
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to integrate water-saving irrigation and controlled drainage technology reasonably and realize the multiple targets including water saving, high yield and pollution alleviation by scientific irrigation and drainage program, this paper carried out a field plot experiment in Lianshui Water Conservancy Research Institute from 2015 to 2016. In the field trial, the water level of paddy field was taken as the technical indicator of irrigation and drainage control, and the amount of irrigation, drainage, leakage, yield and loss of nitrogen and phosphorus in paddy field were monitored and analyzed. A total of 3 treatments were designed in the field test plot, including CK (controlled irrigation and traditional drainage), LCID (controlled irrigation and drainage that allowed mild water stress) and HCID (controlled irrigation and drainage that allowed severe water stress). These 2 kinds of controlled irrigation and drainage procedures both added the allowed flooding depth after rain but had different lower limits of irrigation, one of which was -200 mm and the other of which was -500 mm. The results showed that compared with CK, the utilization of LCID can reduce 11.89% of the irrigation quota and 52.72% of the drainage amount. At the same time, the runoff losses of the total phosphorus (TP), ammonia nitrogen (NH<inf>4</inf><sup>+</sup>-N) and nitrate nitrogen (NO<inf>3</inf><sup>-</sup>-N) were significantly decreased by 54.58%, 36.29% and 60.10% respectively owing to the drop of drainage peak value and drainage times during the critical periods, but the leaching losses of TP and NH<inf>4</inf><sup>+</sup>-N increased on the account of higher seepage in the rain spell. Meanwhile, by comparison with CK, the irrigation times deducted, irrigation amount saved by 29.88% and drainage amount reduced by 58.95% under HCID. Besides, the runoff losses of TP, NH<inf>4</inf><sup>+</sup>-N and NO<inf>3</inf><sup>-</sup>-N were significantly decreased by 59.23%, 38.88% and 62.97% respectively, but the leaching losses of those were increased by 24.57%, 30.17% and 15.88% which would be likely to cause groundwater contamination and soil nutrients loss. In terms of rice yields and its components, LCID and HCID cut down the number of effective panicles per square meters, but the theoretical and actual rice yield showed no significant decline. On the basis of test results, this paper optimized the irrigation and drainage schemes so as to guide practice in southern China rice cultivable area. The evaluation index system was comprised of 3 first-class indexes as field, water-saving and pollution control and 9 second-class indexes. In addition, the combination weights method based on rank correlation analysis method and entropy method was used to obtain the weights of evaluation index, in addition, TOPSIS (technique for order preference by similarity to an ideal solution) served as decision-making method. The evaluation results revealed that LCID had great water conservation benefit and pollutant abatement effect on the premise of ensuring grain production.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Water pollution control
Controlled terms:Agricultural runoff - Decision making - Drainage - Groundwater - Groundwater pollution - Irrigation - Leaching - Nitrogen - Optimization - Phosphorus - Rain - Water conservation - Water levels - Water management
Uncontrolled terms:Controlled irrigations - Evaluation index system - Groundwater contamination - Loss of nitrogen and phosphorus - Nitrogen and phosphorus loss - Rank correlation analysis method - Rice fields - Water-saving irrigation
Classification code:443.3 Precipitation - 444 Water Resources - 444.2 Groundwater - 453.1 Water Pollution Sources - 453.2 Water Pollution Control - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods - 821.5 Agricultural Wastes - 912.2 Management - 921.5 Optimization Techniques
Numerical data indexing:Percentage 1.19e+01%, Percentage 1.59e+01%, Percentage 2.46e+01%, Percentage 2.99e+01%, Percentage 3.02e+01%, Percentage 3.63e+01%, Percentage 3.89e+01%, Percentage 5.27e+01%, Percentage 5.46e+01%, Percentage 5.90e+01%, Percentage 5.92e+01%, Percentage 6.01e+01%, Percentage 6.30e+01%, Size -2.00e-01m, Size -5.00e-01m
DOI:10.11975/j.issn.1002-6819.2018.07.017
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 33>
Accession number:20182405313531
Title:Progress of control technologies on exhaust emissions for agricultural machinery
Authors:Tan, Piqiang (1); Wang, Deyuan (1); Lou, Diming (1); Hu, Zhiyuan (1)
Author affiliation:(1) School of Automobile, Tongji University, Shanghai; 201804, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:1-14
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an important type of non-road machinery, agricultural machinery plays an important role in national economy. At present, the main power source of agricultural machinery is diesel engine. However, the inherent combustion mode of diesel engine leads to large amounts of pollutant emission such as particulate matter (PM) and nitrogen oxide (NOx), and PM and NOx can cause great damage to human health and ecological environment. Therefore, exhaust emission control technology research for agricultural machinery is of great significance. From 3 aspects, this paper elaborates agricultural machinery emission legislation, individual technical routes to reduce agricultural machinery emissions, and combined technical routes to meet more stringent emission limits. Agricultural machinery emissions legislation part analyzes regulations of the EU (European union), the United States and China on exhaust emission limits, test cycles requirements, and their differences. The current agricultural machinery emission legislation for agricultural machinery in China is Stage III. Compared with the standard of Stage IV implemented by the EU and the standard of Tier IV implemented by the United States, exhaust emission limits of China III are relatively relaxed. Legislation of the EU, the United States and China for agricultural machinery increases the non-road transient cycle (NRTC) from Stage IIIB, Tier IV and China IV, respectively. Unlike the EU, China and the United States stipulate that agricultural machinery diesel engines of non-constant speed below 19 kW can also be tested under the cycle of 6 working conditions. In EU and China, the final measuring results of exhaust emissions consist of 10% of the cold start and 90% of the hot start, while the United States reduced the proportion of cold start test cycle results to 5%. Individual technical routes of agricultural machinery emission control mainly include oil technologies, engine purification technologies, and exhaust after-treatment technologies. Among them, oil technologies include improving the quality of fuel and lubricating oil, use of alternative fuels, and so on. Engine purification technologies include diesel engine optimization design for agricultural machinery, supercharging and supercharged intercooler, fuel injection optimization, and EGR (exhaust gas recirculation). Exhaust after-treatment technologies include DOC (diesel oxidation catalyst) technology, DPF (diesel particulate filter) technology and SCR (selective catalytic reduction) technology. Oil technology is a prerequisite for agricultural machinery exhaust emission control, while engine purification technology is the foundation. Advanced exhaust after-treatment technology is the key to meet stringent emission limits for agricultural machinery. Combined technology routes summarize the methods to meet China III and IV emission limits and the latest foreign emission limits. Diesel engines using the "optimized combustion + SCR" route save 5%-7% fuel compared with diesel engines using the "EGR + DPF/CDPF (catalytic diesel particulate filter)" route. Deducting urea consumption, the former route still saves 2%-3% fuel. "Optimized combustion + SCR" route is used in the EU commonly, while "EGR + DPF/CDPF" is usually used in the United States. Considering actual situation in China, there is still much room for improvement in fuel quality, but urea production is very common, so the implementation of China IV legislation prefers SCR. Of course, to find proper routes for agricultural machinery exhaust emission control, it needs to consider the power of agricultural machinery diesel engine, displacement and specific use of the environment, and other requirements. Finally, this paper summarizes the prospects of agricultural machinery emission control technologies. To meet the future China IV limits, it is a significant measure to install an exhaust after-treatment catalytic converter for agricultural machinery. Developing an integrated exhaust after-treatment catalytic converter with low cost and high purification efficiency may become an important research direction for the future emission control of agricultural machinery.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:64
Main heading:Diesel engines
Controlled terms:Agricultural machinery - Agriculture - Air filters - Alternative fuels - Catalytic converters - Catalytic oxidation - Combustion - Construction equipment - Emission control - Exhaust gas recirculation - Exhaust gases - Fuel filters - Gas fuel purification - Laws and legislation - Machine design - Metabolism - Nitrogen oxides - Petroleum prospecting - Promethium - Roads and streets - Selective catalytic reduction - Urea
Uncontrolled terms:Diesel oxidation catalyst - Diesel particulate filters - Ecological environments - Emission control technologies - Exhaust emission control - Exhaust emission limits - Non road transient cycles - Purification efficiency
Classification code:405.1 Construction Equipment - 406.2 Roads and Streets - 451.1 Air Pollution Sources - 451.2 Air Pollution Control - 512.1.2 Petroleum Deposits : Development Operations - 522 Gas Fuels - 547.2 Rare Earth Metals - 601 Mechanical Design - 612.1.1 Internal Combustion Engine Components - 612.2 Diesel Engines - 804.1 Organic Compounds - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 971 Social Sciences
Numerical data indexing:Percentage 1.00e+01%, Percentage 2.00e+00% to 3.00e+00%, Percentage 5.00e+00%, Percentage 5.00e+00% to 7.00e+00%, Percentage 9.00e+01%, Power 1.90e+04W
DOI:10.11975/j.issn.1002-6819.2018.07.001
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 34>
Accession number:20182405313556
Title:Design and application effect of yak barn with window and insulated barn in alpine region
Authors:Chen, Zhaohui (1, 2); Chen, Zepeng (1, 2); Zhang, Libin (3); Luo, Xiaolin (4); Liu, Jijun (1, 2); Guan, Jiuqiang (4)
Author affiliation:(1) College of Animal Science and Technology, China Agricultural University, Beijing; 100193, China; (2) State Key Laboratory of Animal Nutrition, Beijing; 100193, China; (3) Beijing Kingpeng Global Husbandry Technology Co. LTD, Beijing; 100094, China; (4) Sichuan Academy of Grassland Sciences, Chengdu; 611731, China
Corresponding author:Liu, Jijun(liujijun@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:200-208
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to solve the problems of low productivity of yaks and degradation of pasture quality caused by traditional grazing methods in alpine pasturing areas, the study draws on the feeding technology of common beef cattle, combined with the actual conditions of high-cold pastoral areas, a barn with windows and a uninsulated barn in Hongyuan County, Sichuan Province were designed, which were put into production to compare the effect in practice after completing construction. Barn with windows had been built in double slope style with light steel structure, the size of the barn with windows was 63 m × 9 m × 3.2 m, and the breadth of this barn were 6 m. Barn located at 15° east of south. In order to increase the indoor solar area in the whole winter, roof solar belts and long windows with 1.5 m high were set up on the south, according to the sun sunshine. The north side had set up 21 windows with 1.5 m × 1.5 m to reduce the cold air infiltration, which is conducive to yak breeding. Besides, in order to meet the yak ventilation requirements, ventilation chain was set with height of 0.16 m under the eaves. The yaks in the barn with windows were feed with free stall mode, mechanical feeding, mechanical and manual cleaning combined, drinking warm water with drink sink. The size of the uninsulated barn was 63 m × 7.5 m × 3.2 m, and the style was same with the barn with windows, except there were no roof solar belts and no walls on the south, the yarks could walk to the playground. The yaks in the uninsulated barn were feed with free stall mode, manual feeding, manual cleaning, drinking water with by themselves. After the completion of the cattle house, the yak was raised according to the test requirements, and the environment and production index of the two types of yak houses were measured. The results showed that, the temperature of the two barns were 4.17 and -1.02℃, the maximum temperature difference was 8.23℃, the relative humidity of the two barns were 43.25% and 30.94%, and the CO<inf>2</inf>of the two barns were 1313 and 669 mg/m<sup>3</sup>, which meant that the difference was significant (P <0.05). The content of NH<inf>3</inf>in two barns were 0.55 and 0.59 mg/m<sup>3</sup>, and the wind speed in two barns were 0.30 and 0.06 m/s, but the difference was not significant (P>0.05). The two barns' weight gain were 0.30 and -0.06 kg/(day·head), and the difference was very significant (P<0.01). The feed intake were 4.04 and 3.96 kg/(day·head), the difference was not significant. The profits of each yark in barn with windows exceed that of uninsulated barn about 190.60 yuan per month on average. The temperature of insulated barn was higher than that of uninsulated barn, and the weight gain was faster, so barn with windows is more applicable than uninsulated one when considering of economic feasibility, and the environment is more comfortable.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:23
Main heading:Farm buildings
Controlled terms:Architectural design - Feeding - Potable water - Roofs - Wind
Uncontrolled terms:Alpine regions - Environment evaluation - Housing design - Production performance - Yaks
Classification code:402 Buildings and Towers - 402.1 Industrial and Agricultural Buildings - 443.1 Atmospheric Properties - 444 Water Resources - 691.2 Materials Handling Methods
Numerical data indexing:Mass_Density 1.31e-03kg/m3, Mass_Density 5.50e-07kg/m3, Mass_Density 5.90e-07kg/m3, Mass_Density 6.69e-04kg/m3, Percentage 3.09e+01%, Percentage 4.32e+01%, Size 1.50e+00m, Size 1.60e-01m, Size 3.20e+00m, Size 6.00e+00m, Velocity 3.00e-01m/s, Velocity 6.00e-02m/s
DOI:10.11975/j.issn.1002-6819.2018.07.026
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 35>
Accession number:20182405313564
Title:Design and test of ZMFQSL-1 type ramie fiber opening and washing machine
Authors:Su, Gongbing (1); Wu, Qiming (1); Yuan, Langjia (1); Zhou, Huiyong (1)
Author affiliation:(1) School of Mechanical Engineering and Automation, Wuhan Textile University, Wuhan; 430073, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:264-270
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The successful development of this machine can provide an efficient, safe and reliable device for the ramie fiber opening and washing. It can also greatly reduce the requirement of operator technology and the work intensity, but improve the working environment. While it provides a basis not only for the upgrading and updating of ramie processing equipment but also for the scale and Standardized development of ramie production, shows a new design idea for the opening and washing of other degummed fiber at the same time. The problems of fiber opening and washing after the degumming of ramie have plagued the development of the industry for a long time. At present, because of the high labor intensity and low efficiency of manual cleaning, it is the inevitable choice to achieve the goals of mechanized and efficient water washing. Focusing on the problems of follow-up processing of degummed fiber, many technicians both here and abroad have designed many types of ramie opening machines, such as traditional circular knocking machine, rotary hammer type fiber opening machine and ramie fiber washing machine. But now people still use the traditional circular knocking machine to open the fiber and wash it in another machine, which depends on the operators' experience to flip the fiber in the process of knocking and opening the fiber. But, the operators cannot flip so symmetrically because of the bad working environment that the opening machine misses some knockings, which results in the bad uniformity of ramie fiber. According to the technical requirements of ramie fiber automatic production, the ZMFQSL-1 type ramie fiber opening and washing machine was designed and manufactured. This prototype mainly consists of opening device, intermittent transportation device, gathering device, washing device, and system of water circulation. It adopts the combination of the opening device and intermittent transportation device to realize the process of fiber strip-shaped linear intermittent transportation, knocking and opening, and intermittent transportation. By using eccentric design of cam and cam follower assembly, the opening device can realize the hammer's free falling motion and finish the knocking and opening of the ramie fiber. Washing device is made up of 5 sets of washing mechanisms which are in ladder arrangement, and it can complete the washing process of the ramie fiber by the pressure water washing of 2 sides during the conveying and the extrusion of the pressure roll, which achieves the further opening and washing of fiber as well as the recycling of water resource, and at the same time increases the feasibility of the popularizing of the prototype. The size of the prototype (length × width × height) is 12 000 mm × 1 100 mm × 1 780 mm, and its power of electric machinery is 14 kW. The operation widths of opening device and washing device are 850 mm, and the nozzle pressure of the washing device is 1.2 MPa. Experiment result shows that the machine works stably and performs reliably, the productivity is more than 120 kg/h and the quality of ramie fiber is uniform, the average residual gum content is less than 2.0%, the Bundle-fiber breaking force is 4.3 cN/dtex, and the splitting rate is less than 2‰, and every indicator of performance meets or exceeds the related standards. The successful development of this machine can provide an efficient, safe and reliable device for the ramie fiber opening and washing. It can also greatly reduce the requirement of operator technology and the work intensity, and improve the working environment. It provides a basis not only for the upgrading and updating of ramie processing equipment but also for the scale and standardized development of ramie production, and shows a new design idea for the opening and washing of other degummed fiber at the same time.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:20
Main heading:Washing
Controlled terms:Agricultural machinery - Cams - Fibers - Hammers - Hemp - Machine design - Washers - Washing machines - Water recycling - Water resources
Uncontrolled terms:Automatic production - Design and tests - Mechanism design - Performance tests - Processing equipment - Technical requirement - Water circulation - Working environment
Classification code:444 Water Resources - 601 Mechanical Design - 605.2 Small Tools, Unpowered - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products
Numerical data indexing:Mass_Flow_Rate 3.33e-02kg/s, Percentage 2.00e+00%, Power 1.40e+04W, Pressure 1.20e+06Pa, Size 1.78e+00m, Size 8.50e-01m
DOI:10.11975/j.issn.1002-6819.2018.07.034
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 36>
Accession number:20182405313562
Title:Quality evaluation of rural collective construction land based on GIS and comprehensive index method
Authors:Zhao, Xiaomin (1); Zhou, Bingjuan (1); Huang, Xinyi (1); Yi, Dan (1); Lai, Xiahua (1); Chen, Lei (1)
Author affiliation:(1) Key Laboratory of Poyang Lake Watershed Agricultural Resources and Ecology of Jiangxi Province, Jiangxi Agricultural University, Nanchang; 330045, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:249-255
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Land quality is the core of rural collective construction land reform in China and is the basis for the evaluation of the benchmark price of rural collective construction land. In the year of 2015, Yujiang County in Jiangxi Province was selected by the Chinese government as the pilot county to launch the rural residential land reform. This reform made the Yujiang County become a perfect place to carry out the research on the rural collective construction land quality evaluation and gradation. In this paper, we firstly analyzed the connotation of rural collective construction land and its similarities and differences with the state-owned construction land. Jinjiang Town, Huangxi Town, Honghu Town and Maquan Town in Yujiang County were selected as the research areas based on the representation of the spatial distribution and identical development type. Secondly, the technical approaches and the evaluation indicator system for rural collective construction land quality evaluation were constructed referred to some relevant technical processes and methods. These reference materials mainly include the state-owned urban construction land gradation, the agricultural land gradation and classification. The technical approaches and the evaluation indicator system for rural collective construction land quality evaluation had fully reflected the characteristics of collective construction land and met the requirements of the ecological civilization construction to the land quality. Lastly, the comprehensive index method was applied to calculate the collective construction land quality scores in 4 research towns. The collective construction land quality scores were graded according to the method combining the total score frequency histogram method and the field verification. The results showed: 1) The rural collective construction land quality evaluation system was different from the technical process of state-owned construction land gradation. This research chose some factors which could influence the rural collective construction land gradation, such as the net income per capital, the distance to built-up area, the rural electronic commerce availability, the construction condition of public service facilities, the farmland area per capital, the rural residential area per capital, the implementation of spatial plans, the green land proportion, the garbage disposal condition.2)The rural collective construction land quality in Jinjiang Town was divided into 4 levels, that in Huangxi Town was divided into 3 levels, that in Honghu Town was divided into 3 levels, and that in Maquan Town was divided into 2 levels.3) The second level of rural collective construction land possessed the largest proportion of each town's area.4) The rural collective construction land with higher land quality grade in 4 towns was mainly distributed in the areas with higher population density and rural collective construction land distribution density, closer to state-owned urban construction land and main traffic roads.From this research, we strongly recommend formulating the technical standards for gradation and price evaluation of collective construction land in time, and land management department should take actions to promote quality evaluation and benchmark land price assessment of collective construction land.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Quality control
Controlled terms:Benchmarking - Costs - Geographic information systems - Grading - Housing - Land use - Population statistics - Rural areas
Uncontrolled terms:Collective constructions - Comprehensive index method - Evaluation indicator system - Frequency histograms - Quality evaluation - Rural regions - Rural residential areas - Yujiang County
Classification code:403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 903.3 Information Retrieval and Use - 911 Cost and Value Engineering; Industrial Economics - 913.3 Quality Assurance and Control
DOI:10.11975/j.issn.1002-6819.2018.07.032
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 37>
Accession number:20182405313558
Title:Characteristics and mechanism of lead adsorption from aqueous solutions by oil crops straw-derived biochar
Authors:Zhang, Lianke (1, 2); Liu, Xinyu (1); Wang, Weida (1); Li, Yumei (1); Sun, Peng (1); Shang, Shaopeng (1); Jiang, Qinghong (1)
Author affiliation:(1) School of Energy and Environment, Inner Mongolia University of Science and Technology, Baotou; 014010, China; (2) School of Environment and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an; 710055, China
Corresponding author:Shang, Shaopeng(297356651@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:218-226
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, with the continuous development of economy, heavy metal pollution becomes increasingly serious. Biochar is often obtained from agriculture wastes through pyrolysis, in which the biomass is subjected to thermochemical conversion under an oxygen-limited condition. As a new type of cheap efficient adsorbent, because of the larger specific surface area and high surface energy, and the surface containing rich-oxygen functional groups, biochar has a good application prospect in wastewater treatment, causing great interest for scientist. Flax (Sesamum indicum) and rape (Brassica campestris L.) are the typical oil crops, which are kinds of good raw material for producing biochars. However, large amounts of flax straw (FS) and rape straw (RS) are discarded or incinerated directly and cause resource waste and environmental pollution seriously. In order to utilize the waste biomass resources, 2 types of biochars derived from FS and RS were prepared by pyrolyzing at a temperature of 700℃ under oxygen-limited condition, and the adsorptions of Pb2+ in aqueous solutions were evaluated. The effects of contact time, initial Pb2+ concentration and initial pH value in batch experiments were investigated by the 4 kinds of adsorption kinetics models (Pseudo first-order, Pseudo second-order, Elovich and Intra-particle diffusion model) and the 4 kinds of isothermal adsorption models (Langmuir, Freundlich, Temkin and D-R model). The structure and properties of biochars were characterized by using Brunauer-Emmett-Teller (BET) surface area and pore size analysis, scanning electron microscope (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectrometer (FTIR), which were used to preliminarily analyze adsorption mechanism. The results showed that the BET surface areas of RS and FS were 84.44 and 172.61 m<sup>2</sup>/g, respectively; SEM showed that the surface of 2 kinds of biochars was smooth, and the pore structure was compact and regular; FTIR indicated that the active functional groups such as CO32- (675-750, 835-886 cm<sup>-1</sup>), secondary alcohol (1 017 cm<sup>-1</sup>), C-C (1 437 cm<sup>-1</sup>), -COOH or C=O (1 578 cm<sup>-1</sup>), C=C (1 687 cm<sup>-1</sup>), -CH2- (2 800-3 000 cm<sup>-1</sup>), -OH (3 307 cm<sup>-1</sup>) were found to be rich on the surfaces of 2 kinds of biochars, and all of the properties were good for Pb2+ adsorption. The XRD patterns suggested that carbonate and basic carbonate containing Pb2+ were present in these biochars after adsorption. The adsorption equilibrium of RS and FS was reached in 4 and 10 h, respectively, and the adsorption capacity of RS and FS reached 307.59 and 220.07 mg/g, respectively. The adsorption kinetics were best fitted by the Pseudo second order model, while the isothermal adsorption was best described by Langmuir isotherm. This indicated that Pb2+ ions were adsorbed onto 2 kinds of biochars via monolayer. The adsorption mechanism for Pb2+ was a complex interaction of physical and chemical factors, mainly including electrostatic interaction, ion exchange/ligand exchange, cationic-π and precipitation. The results obtained show that 2 kinds of oil crop biochars are both excellent adsorbents to Pb2+ in aqueous solution and will provide important information on applying as low cost adsorbents for removal of heavy metals in contaminated water.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:33
Main heading:Adsorption
Controlled terms:Adsorbents - Adsorption isotherms - Agricultural wastes - Chemicals removal (water treatment) - Crops - Dyes - Flax - Fourier transform infrared spectroscopy - Heavy metals - Ion exchange - Lead - Linen - Oxygen - Pore size - Precipitation (chemical) - Scanning electron microscopy - Solutions - Wastewater treatment - Water pollution - X ray diffraction - Yarn
Uncontrolled terms:Bio chars - Brunauer-emmett-teller surface areas - Characteristics and mechanisms - Environmental pollutions - Fourier transform infrared spectrometer - Pseudo-second order model - Structure and properties - Thermochemical Conversion
Classification code:452.4 Industrial Wastes Treatment and Disposal - 453 Water Pollution - 531 Metallurgy and Metallography - 546.1 Lead and Alloys - 801 Chemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 819 Synthetic and Natural Fibers; Textile Technology - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 951 Materials Science
Numerical data indexing:Specific_Surface_Area 1.73e+05m2/kg, Specific_Surface_Area 8.44e+04m2/kg, Time 1.44e+04s, Time 3.60e+04s
DOI:10.11975/j.issn.1002-6819.2018.07.028
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
<RECORD 38>
Accession number:20182405313544
Title:Temporal and spatial variation of wetting volume under sub-irrigation with vertical emitter
Authors:Bai, Dan (1); Sun, Shuzhen (1); Ren, Peiqi (1); Xu, Xianbo (1); Liang, Zhidong (1)
Author affiliation:(1) Institute of Water Resource and Hydroelectric Engineering of Xi'an University of Technology, Xi'an; 710048, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:34
Issue:7
Issue date:April 1, 2018
Publication year:2018
Pages:107-113
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The temporal and spatial variation of soil wetting characteristics and the influencing factors of vertical tube sub-irrigation were studied. In this article, the effects of working head, soil bulk density, initial soil moisture, diameter of vertical tube and buried depth of vertical tube on the spatial distribution of soil wetting were studied based on the experiment of indoor vertical tube emitter infiltration. In this experiment, the experiment was conducted using an orthogonal design method including 18 treatments. The orthogonal experimental design was adopted to arrange the influenced factors including water head, soil bulk density, initial soil moisture, diameter of vertical tube and buried depth of vertical tube (all the factors had 3 levels) and to study the characteristic parameters of wetted soil volume under sub-irrigation with vertical tube emitter. In the test, the pressure head was designed with different levels of 0.8, 1.1 and 1.4 m, and the soil bulk density was 1.32, 1.35 and 1.38 g/cm<sup>3</sup>. The initial soil moisture was 4%, 7% and 10%, and the diameter of the vertical tube was 4, 8 and 12 mm, the depth of vertical tube was 15, 20 and 25 cm. After the infiltration of started, observed and recorded the wetting front in the horizontal, upward and downward directions with the stopwatch, the corresponding wet body shape was obtained at different times. The cumulative infiltration into the soil was recorded by the scale on the Markov's bottle. The result showed that the shape of the wet body formed by the infiltration test of the vertical tube emitter was approximately an ellipsoid, and the horizontal diffusion radius and vertical infiltration distance of the wetting body increased with the infiltration time. At the early stage of irrigation, the wet front was basically consistent in the 3 directions, the distance between the downward movement and the upward and horizontal directions gradually increased with time, and finally the downward migration distance was the largest. According to the wet front migration distance in the 3 directions recorded at different times, the water head, soil bulk density, initial soil moisture, diameter of vertical tube emitter and buried depth of vertical tube in the 3 directions were established by using multiple regression and the coefficient of determination was above 0.85, which showed the reliable quantitative relationship between the migration distance of the wetting body and the influencing factors. According to the standardized regression coefficients, the infiltration time, water head and soil bulk density had a significant effect on the wetting body. The influence of the water head, the initial soil moisture, the diameter of the vertical pipe and the depth of the vertical tube on the wetting body was positive correlation. The effect of soil bulk density on the wetting body was negative. The 5 factors had different influential degree on the characteristic parameters of the wetting body. When the vertical tube emitter diameter, the initial moisture content and water head were increased, the wetting distance was increased. According to the quantitative relationship between the wet front migration distance and the influencing factors in different directions, the relationship between the wetting front migration rate and the influencing factors in different directions was established. It showed that the wetting front migration rate began to increase at the beginning of irrigation. With the increase of infiltration time, the wetting front migration rate gradually decreased. After infiltration for 200 min, infiltration gradually stabilized.<br/> © 2018, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Infiltration
Controlled terms:Bottles - Design of experiments - Irrigation - Moisture - Moisture determination - Soil moisture - Soils - Tubes (components) - Wetting
Uncontrolled terms:Coefficient of determination - Emitters - Migration distance - Orthogonal experimental design - Soil volume - Standardized regression coefficients - Temporal and spatial variation - Wetting fronts
Classification code:483.1 Soils and Soil Mechanics - 619.1 Pipe, Piping and Pipelines - 694.2 Packaging Materials - 821.3 Agricultural Methods - 901.3 Engineering Research - 944.2 Moisture Measurements
Numerical data indexing:Mass_Density 1.35e+03kg/m3, Mass_Density 1.38e+03kg/m3, Percentage 1.00e+01%, Percentage 4.00e+00%, Percentage 7.00e+00%, Size 1.10e+00m, Size 1.20e-02m, Size 1.40e+00m, Size 2.00e-01m, Size 2.50e-01m, Size 8.00e-03m, Time 1.20e+04s
DOI:10.11975/j.issn.1002-6819.2018.07.014
Database:Compendex
Compilation and indexing terms, Copyright 2018 Elsevier Inc.
期刊信息
- 主管单位 中国科学技术协会
- 主办单位 中国农业工程学会
- 主编 朱明
- 总编/社长 王应宽
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