2017年1月第33卷第2期

2017年1月第33卷第2期

Accession number:20171503558493
Title:Design and experiment on real-time monitoring system of wheat seeding
Authors:Lu, Caiyun (1, 2); Fu, Weiqiang (1, 2); Zhao, Chunjiang (1, 2); Mei, Hebo (1, 2); Meng, Zhijun (1, 2); Dong, Jianjun (1, 2); Gao, Nana (1, 2); Wang, Xiu (1, 2); Li, Liwei (1, 2)
Author affiliation:(1) Beijing Research Center of Intelligent Equipment for Agriculture, Beijing; 100097, China; (2) Beijing Research Center for Information Technology in Agriculture, Beijing; 100097, China
Corresponding author:Zhao, Chunjiang(zhaocj@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:32-40
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To monitor wheat planting performance on real time, a real-time monitoring system of wheat planting performance based on CAN bus was designed. The general structure of the system was elaborate, the hardware and software of the system was designed and the field experiment was conducted. The system included sensor unit for signal collecting, monitoring module, Controller Area Network (CAN) module and terminal, and could monitor the status of seed tube, working speed, rotation velocity of seed shaft. Photoelectric sensor was used to convert quantities of seed tube status into voltage signals, and hall sensor was used to convert quantities of wheel axis rotation velocity into pulse signals. Monitoring module judge the status of seed tube (normal, blocked and missing), and calculate the rotation velocity of wheel axis and seed shaft based on the signals output by sensors. At the same time, monitoring module calculate working speed according to the rotation velocity of wheel axis information. Then the information obtained by monitoring module was uploaded to terminal by CAN bus and displayed on real time on the terminal. The result of the experiment showed that there was no false alarm at the working speed of 10 km/h, the monitoring accuracy of seed tube fault status was >98%, blocked alarm response time <0.2 s, missing alarm response time <0.5 s. The system worked reliably and had a strong ability to anti-dusting and anti-vibration, and effectively monitored wheat planting performance. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Monitoring
Controlled terms:Alarm systems - Control system synthesis - Crops - Design - Hall effect transducers - Photoelectricity - Response time (computer systems) - Rotation - Seed - Sensors - Tubes (components) - Velocity - Wheels
Uncontrolled terms:Controller area network - General structures - Hardware and software - Monitoring accuracy - Photoelectric sensors - Real time monitoring system - Wheat planting - Working speed
Classification code:601.2 Machine Components - 619.1 Pipe, Piping and Pipelines - 701.1 Electricity: Basic Concepts and Phenomena - 731.1 Control Systems - 821.4 Agricultural Products - 931.1 Mechanics
Numerical data indexing:Velocity 2.78e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.02.005

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558521
Title:Determination of carbon dioxide concentration standards and minimum ventilation rates of layer house in winter
Authors:Wang, Yang (1, 2); Wang, Chaoyuan (1, 3); Li, Baoming (1, 3)
Author affiliation:(1) Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, Beijing; 100083, China; (2) College of Water Resources and Civil Engineering, China Agricultural University, Beijing; 100083, China; (3) Beijing Engineering Research Center for Animal Healthy Environment, Beijing; 100083, China
Corresponding author:Li, Baoming(libm@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:240-244
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The CO<inf>2</inf>concentration is required to be below 1500 mg/m3(Environmental Quality Standards for the Livestock and Poultry Farm of China, published in 1999) in layer hen houses where the manure is disposed by powered scraper, the litters generally need to remind and the drinking device has water leak. Consequently, moisture and NH<inf>3</inf>levels in such barns are much high. Also, air temperature is much lower in winter, because the minimum ventilation rate is large in winter. However, the manure is cleaned daily in new poultry house with manure convey belt. Meanwhile, the aerial pollutants (CO<inf>2</inf>and NH<inf>3</inf>) are reduced and the relative humidity is decreased. Indoor air quality in this kind of poultry house is dramatically improved. A new standard of CO<inf>2</inf>concentration and the minimum ventilation rate of layer house with manure convey belt should be reconsidered. Determining the CO<inf>2</inf>concentration standards for the manure convey belt in layer hen houses is needed. The objectives of this work were to draw a conclusion about the CO<inf>2</inf>concentration levels and use it as a reference to calculate the minimum ventilation rate in winter. This review summarized the recent measurements of the emission rates of aerial NH<inf>3</inf>and the CO<inf>2</inf>concentrations in poultry houses in which the laying hens were kept in cages. The relationship between CO<inf>2</inf>and NH<inf>3</inf>was also described based on the data got in the poultry houses with different manure removing way from the domestic and foreign study. In addition, the minimum ventilation rate is important for ensuring the ideal air quality in poultry house in winter. The optimum ventilation is one of the factors affecting poultry production and energy consumption. Considering the mass conservation under steady-state conditions in the layer hen building, there are 2 main sources of CO<inf>2</inf>in poultry house, and most of the CO<inf>2</inf>is produced by respiration processes of layer hens, if neglecting the amount of CO<inf>2</inf>emitted from manure. The minimum temperature value for layer houses was 13℃ in this study. The following conclusions were drawn in this study: 1) There was a positive and significant correlation between CO<inf>2</inf>and NH<inf>3</inf>concentration in layer houses based on analyzing the data of previous researches. The standards of CO<inf>2</inf>concentration and NH<inf>3</inf>concentration were suggested to be 5000 mg/m3and less than 15 mg/m3respectively in the layer hen houses with manure convey belt. This condition would not reduce the hen's performance and defenses. Primary CO<inf>2</inf>concentration standards persisted when the feces were scraped by powered scraper to a cross conveyor at the end of the barn; 2) Average NH<inf>3</inf>concentrations in the layer house with manure convey belt was largely less than the traditional house with the scraper. Therefore, rebuilding new layer hen's building equipped with the manure convey belt is crucial not only for indoor environment, but also for ventilation system; 3) Ventilation rate was calculated using the rate of laying hen in winter based on CO<inf>2</inf>mass balances from the literature. The constantly minimum ventilation rates were 0.40-0.50 m3/(h·kg) for the layer houses with manure convey belt. The new standards of CO<inf>2</inf>concentration and ventilation rate were beneficial for improving indoor environment control and ventilation energy efficiency, and saving constructional costs. Furthermore, the results of this paper provide the reference for solving the contradiction between ventilation and insulation system in layer house. Also, it can improve the versatility of poultry environment and provide the support for emission studies using the new standard of the CO<inf>2</inf>to evaluate the poultry building environment. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Carbon dioxide
Controlled terms:Agriculture - Air quality - Atmospheric composition - Energy efficiency - Energy utilization - Environmental management - Facilities - Farm buildings - Fertilizers - Historic preservation - Houses - Indoor air pollution - Leakage (fluid) - Manures - Potable water - Standards - Tools - Ventilation
Uncontrolled terms:Carbon dioxide concentrations - Concentration levels - Environmental control - Environmental quality standards - Indoor environment control - Minimum temperatures - Steady-state condition - Ventilation rate
Classification code:402.1 Industrial and Agricultural Buildings - 402.3 Residences - 444 Water Resources - 451 Air Pollution - 451.2 Air Pollution Control - 454.1 Environmental Engineering, General - 525.2 Energy Conservation - 525.3 Energy Utilization - 643.5 Ventilation - 801 Chemistry - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.2 Codes and Standards
Numerical data indexing:Mass_Density 1.50e-03kg/m3, Mass_Density 1.50e-05kg/m3, Mass_Density 5.00e-03kg/m3
DOI:10.11975/j.issn.1002-6819.2017.02.033

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558496
Title:Reducing soot and NO emission from diesel engine exhaust catalyzed by nano-CeO<inf>2</inf>
Authors:Huang, He (1); Sun, Ping (1); Liu, Junheng (1); Ye, Song (1)
Author affiliation:(1) School of Automotive and Traffic Engineering, Zhenjiang; 212013, China
Corresponding author:Liu, Junheng(liujunheng365@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:56-60
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nitrogen oxide (NO<inf>x</inf>) and particulate matter (PM) are the main emissions for diesel engines. Because of their contradictory relationship of generation mechanisms, only using the internal purification technology is very difficult to meet the increasingly stringent diesel emissions regulations. Development and application of after-treatment technology with low cost, high efficiency and high adaptability will be more promising, which should be utilized to control both NO<inf>x</inf>and PM emissions. Rare-earth-based catalysts have rich electronic structure, and show the unique physical and chemical properties. In existing rare earth oxides, cerium oxide has been paid much attention in the field of catalysis because of its low price, unique crystal structure and reversible transformation of trivalent ion (Ce3+) and tetravalent ion (Ce4+). In the recent years, the application of cerium dioxide (CeO<inf>2</inf>) in after-treatment technology for diesel engine is a hot research topic. In this study, 3 groups of nano-CeO<inf>2</inf>were prepared using the coprecipitation method in order to reduce the PM and NO<inf>x</inf>emissions from diesel engine through the after-treatment technology. The samples were characterized by X-ray diffraction (XRD), Brunauer-Emmett-Teller (BET), and hydrogen temperature programmed reduction (H<inf>2</inf>-TPR). What was more, the activity of catalysts was evaluated by ignition temperature and peak temperature of soot combustion as well as conversion ratio from nitric oxide (NO) to nitrogen (N<inf>2</inf>). The experimental results showed that CeO<inf>2</inf>crystal structure had not been changed, and continued to be the cubic fluorite structure. The average particle diameters of the prepared CeO<inf>2</inf>were 7, 12 and 20 nm, respectively, which were much smaller than that of commercial CeO<inf>2</inf>. Compared with commercial CeO<inf>2</inf>, the prepared CeO<inf>2</inf>had larger specific surface area, which indicated that there were more active sites on the surface of CeO<inf>2</inf>for the unit mass. Furthermore, there were more opportunities for the catalyst to be exposed to the reactants, which was beneficial for adsorption and activation of the reactant molecules. The prepared CeO<inf>2</inf>had 3 obvious H<inf>2</inf>reduction peaks, corresponding to the surface absorbed oxygen, surface lattice oxygen and bulk lattice oxygen, respectively. Oxygen species, especially the surface lattice oxygen, had direct relation with catalytic activity. The reduction property of surface oxygen species was stronger, and the catalytic activity was higher. The results of H<inf>2</inf>-TPR had correspondence with the results of BET. For the efficiency of catalytic oxidation, the order of nano-CeO<inf>2</inf>particle size from high to low was 20, 12 and 7 nm, successively. The ignition temperatures of soot combustion were reduced by 124, 109 and 93℃, and the peak temperatures were reduced by 185, 104 and 102℃ respectively with the 3 groups of CeO<inf>2</inf>catalysts. With the increase of temperature, the conversion ratio of NO firstly increased and then decreased. The conversion ratio of NO with 20 nm CeO<inf>2</inf>reached the highest value of 70% at 350℃. The conversion ratio of the 3 groups of CeO<inf>2</inf>catalysts was higher than 68% at 400-520℃, which indicated that CeO<inf>2</inf>has a wide temperature window. The experimental results can provide a reference for optimum design and application of CeO<inf>2</inf>catalyst in the field of diesel exhaust after-treatment system. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Diesel engines
Controlled terms:Catalysis - Catalyst activity - Catalysts - Catalytic oxidation - Cerium - Combustion - Crystal structure - Efficiency - Electronic structure - Emission control - Engines - Exhaust systems (engine) - Ignition - Nanocrystalline materials - Nitric oxide - Nitrogen oxides - Oxygen - Particle size - Particulate emissions - Promethium - Rare earths - Reduction - Soot - X ray diffraction
Uncontrolled terms:After-treatment technology - Brunauer emmett tellers - Conversion ratio of NO - Development and applications - Diesel exhaust after treatments - Hydrogen temperature programmed reduction - Physical and chemical properties - Reversible transformation
Classification code:451.1 Air Pollution Sources - 451.2 Air Pollution Control - 521.1 Fuel Combustion - 547.2 Rare Earth Metals - 612.2 Diesel Engines - 761 Nanotechnology - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 913.1 Production Engineering - 933.1.1 Crystal Lattice
Numerical data indexing:Percentage 6.80e+01%, Percentage 7.00e+01%, Size 1.20e-08m, Size 2.00e-08m, Size 7.00e-09m
DOI:10.11975/j.issn.1002-6819.2017.02.008

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558522
Title:Effect of wave height and direction on hydraulic characteristics of net of pile-column type net enclosure aquaculture system
Authors:Chen, Tianhua (1); Meng, Ang (1); Gui, Fukun (1)
Author affiliation:(1) National Engineering Research Center for Marine Aquaculture, Zhejiang Ocean University, Zhoushan; 316022, China
Corresponding author:Gui, Fukun(gui2237@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:245-251
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The net enclosure aquaculture (NEA) is a new developing ecological aquaculture pattern in shallow water. The typical patterns include the pile-column type NEA, the shore-cascade type NEA and the floating rope NEA. The pile-column type NEA is mainly composed of piles and net panels. The net system is one of the most important factors which affect the security of the whole NEA system. Because of its especial structure, there are few related reports. Therefore, it is of great significance to carry out research on the hydraulic characteristics of unit net of pile-column type net enclosure in waves. Because unit net belongs to the typical flexible structure, the computing model can be established by the lumped mass point method. Based on Newton's second law, the equation of particle motion was established to illustrate the motion response of net panel in wave. Wave force can be calculated through the Morison equation. The equation of motion is a typical second order partial differential equation. There are a variety of methods to solve the equation, such as the Euler method and the Runge-Kutta method. In this paper, the program was computed in code, which could obtain a good convergence by using the Euler method. Firstly, the wave force on cables, and the strain produced by the cable deformation were calculated, with the assumption that the net panel was plane without deformation at the beginning. Secondly, the motion equations of each lumped point, which were typical second order partial differential equation, could be obtained according to the Newton equation. Then, the forward Euler's method was used to calculate the particle displacement and velocity at the next time step. Finally, the particle position and velocity were taken as new state parameters of net panel, and the above steps were repeated until the end of time. The results showed that wave height and wave direction had a significant effect on the maximum tension force in twines, the maximum displacement of nodes and the maximum load at fixing points. The maximum tension of netting twine mainly appeared on both sides of the top position of the net panels and it increased with the wave height increasing. Remarkable increase of the maximum tension in netting twines was found when the wave direction was between 30° and 70°. The maximum offset of net panels was observed mainly at the mid-upper position of the net and it showed a positive correlation with the wave height and wave direction. The maximum load at the fixing points on the pile-column appeared at the top point. The second maximum load point occurred at the bottom. Both of them were much larger than those at the middle fixing points. Therefore, in actual engineering, it is suggested that the fixing points at the top and bottom should be strengthened peculiarly, and the cables at both ends of the top and bottom net should be thickened. At the same time, the maximum offset and corresponding position are important indices for the layout of net and the installation of relevant equipment. So, the reasonable design of related spacing should be considered and the affiliated structures should not be installed within the maximum offset scope to prevent the cables and lines from breaking due to touching and friction. The results of this study are expected to provide theoretical basis and technical support for the design, production and offshore installation of the pile-column type NEA engineering. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Piles
Controlled terms:Aquaculture - Buoyancy - Cables - Computer simulation - Deformation - Enclosures - Equations of motion - Flexible structures - Hydraulic machinery - Models - Partial differential equations - Runge Kutta methods - Twine - Water waves - Waves
Uncontrolled terms:Aquaculture systems - Hydraulic characteristic - Maximum displacement - Offshore installations - Particle displacement - Positive correlations - Second-order partial differential equation - Unit net panel
Classification code:408.2 Structural Members and Shapes - 471.4 Seawater, Tides and Waves - 632.2 Hydraulic Equipment and Machinery - 694.2 Packaging Materials - 723.5 Computer Applications - 821.3 Agricultural Methods - 921.2 Calculus - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.11975/j.issn.1002-6819.2017.02.034

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558502
Title:Rapeseed dreg additive reducing soil infiltration and improving water retention
Authors:Xing, Xuguang (1, 2); Zhang, Pan (1, 2); Ma, Xiaoyi (1, 2)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A&F University, Yangling; 712100, China; (2) Key Laboratory for Agricultural Soil and Water Engineering in Arid Area of Ministry of Education, Northwest A&F University, Yangling; 712100, China
Corresponding author:Ma, Xiaoyi(xiaoyima@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:102-108
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plant dreg is a type of organic matter and a byproduct of vegetable oil extraction. Plant dreg as a fertilizer can be added to soils and it may also improve soil physical properties. An experiment based on the indoor vertical one-dimensional infiltration soil column was conducted to investigate the impact of rapeseed dreg additive on soil-water infiltration, movement, re-distribution and water retention. The soil in the experiment was collected from the 30-cm depth in a cultivated field in the district of Yangling in Shaanxi Province on the Loess Plateau of China (34°17'28″ N, 108°04'30″ E). The particle size of selected soil was measured by Mastersizer-2000 (made in Malvern Instrument Co. Ltd., Britain), and the soil was sandy loam with a particle size distribution of 3.75% for 0-0.002 mm, 21.73% for 0.002-0.02 mm and 74.52% for 0.02-2 mm. Samples were air dried, sieved through a 2 mm mesh, and compacted into plexiglass soil columns with a height and inner-diameter of 40 and 15 cm, respectively. The total soil depth in the column was 34 cm and soil bulk density was 1.45 g/cm3. The rapeseed dreg was air dried, pulverized, and uniformly mixed with soil samples. The plant dreg accounted for 2% of soil weight. The depth of mixed layer was set at 14, 24, and 34 cm. Pure soil samples without additives were used as a control (CK) treatment. A Mariotte bottle was used to provide a free water supply with about 1.5 cm in depth on the surface. The experiment started when the Mariotte bottle opened. The filter paper was laid at the soil surface to make the water head stable. The characteristics of soil water infiltration, distribution and water holding capacity were comparatively analyzed. The results showed that both Philip and Kostiakov models could well describe the relationship between cumulative infiltration and infiltration duration (R2>0.99). Compared with the CK, the soils mixed with plant dreg helped to decrease cumulative infiltration and infiltration rate, both of which decreased as the depth of mixed layer increased. The cumulative infiltration for the soils mixed with 14, 24, and 34 cm was 3.9%, 7.8%, and 11.0% lower than the CK, respectively. The infiltration rate for the soils mixed with 14, 24, and 34 cm was 25.0%, 33.3%, and 41.7% lower than the CK, respectively. From the final water distribution in soil profiles, the soils mixed with plant dreg helped to increase saturated soil moisture and soil water content in soil layers, which were increased by 14.3% and 11.3%, respectively, compared with the CK. This indicated that plant dreg additive could increase soil water retention and water storage in root zone. Plant dreg could increase clay and silt contents from 3.75% to 9.97% and from 21.73% to 55.15%, respectively, and reduce sand content from 74.52% to 34.88%, and the experimental soil changed to silt loam. This indicated that the ratio of medium and small particle-size increased, and the ratio of large particle-size decreased, demonstrating that plant dreg had the potential in improving desertification soils. From the above, mixing plant dreg powder with soils is of significant practical meaning for cultivated soils because of the enhancement of water retention and water storage. This study may provide valuable information for the promotion of plant dreg to cropland and the application and popularity of plant dreg in soil improvement and water-saving agriculture. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Infiltration
Controlled terms:Additives - Bottles - Moisture - Oilseeds - Particle size - Particle size analysis - Silt - Soil moisture - Soil surveys - Soils - Water conservation - Water content - Water supply - Water supply systems
Uncontrolled terms:Cumulative infiltrations - Loess plateau of chinas - Rapeseed dreg - Soil physical property - Soil water retention - Water holding capacity - Water retention - Water-saving agricultures
Classification code:444 Water Resources - 446.1 Water Supply Systems - 483.1 Soils and Soil Mechanics - 694.2 Packaging Materials - 803 Chemical Agents and Basic Industrial Chemicals - 821.4 Agricultural Products - 951 Materials Science
Numerical data indexing:Percentage 2.00e+00%, Percentage 2.17e+01%, Percentage 2.17e+01% to 5.51e+01%, Percentage 2.50e+01%, Percentage 3.33e+01%, Percentage 3.75e+00%, Percentage 3.75e+00% to 9.97e+00%, Percentage 3.90e+00%, Size 1.50e-01m, Percentage 4.17e+01%, Percentage 7.45e+01% to 3.49e+01%, Percentage 7.45e+01%, Percentage 7.80e+00%, Size 0.00e+00m to 2.00e-06m, Size 1.50e-02m, Size 2.00e-03m, Size 2.00e-05m to 2.00e-03m, Size 2.00e-06m to 2.00e-05m, Size 3.00e-01m, Size 3.40e-01m, Size 4.00e-01m, Mass_Density 1.45e+03kg/m3, Percentage 1.10e+01%, Percentage 1.13e+01%, Percentage 1.43e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.014

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558504
Title:Inhibiting effect of nano-carbon on rainfall erosion of different vegetation cover on loess slope land
Authors:Zhou, Beibei (1); Chen, Xiaopeng (1); Lü, Jinbang (1); Ding, Qian (1); Wang, Quanjiu (1, 2)
Author affiliation:(1) State Key Laboratory Base of Eco-hydraulic Engineering in Arid Area, Xi'an University of Technology, Xi'an; 710048, China; (2) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; 712100, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:116-124
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:High weathered soils in arid and semi-arid area are characterized by low soil fertility and high erosion potential. This paper evaluated the influences of nano-carbon on soil erosion and water loss on the sloping land (15°) of the Chinese Loess Plateau. Simulated rainfall experiments were performed on a natural, fallow loessial slope in the Shenmu Erosion and Environment Research Station, Institute of Soil and Water Conservation, Chinese Academy of Sciences, which locates in the Liudaogou watershed, Shenmu County, Shaanxi Province. Five application rates (i.e., 0, 0.1%, 0.5%, 0.7%, and 1.0%) of nano-carbon were selected during the simulated rainfall experiments (rainfall intensity of 60 mm/h); and 4 vegetation species (i.e., caragana, alfafa, bean, and maize) were planted on the slope to evaluate the vegetation effect on soil and water conservation with the bare as the control. A constant-intensity rainfall method was adopted under natural conditions. Field plots were established on the slope that had been fallow for 5 years. The rainfall simulator came from the independent design of Xi'an University of Technology. Under the 60 mm/h rainfall intensity, the simulated rainfall experiments were carried out for 50 times in the 25 different pretreated plots in order to estimate soil erosion and water loss for all the treatments. The main results were as follows: the initial runoff time was delayed with the increase of nano-carbon contents. Compared to the control treatment without nano-carbon application in bare land, the initial runoff time in alfalfa plot was delayed by 287.1%, which was the most obvious. Furthermore, with the increase of nano-carbon contents, the runoff in each treatment decreased obviously. The nano-carbon alfalfa coverage also had the most obvious effect in the reducing runoff, and the runoff was reduced by 66.47%; for other vegetation species, the reduction was between 31.5% and 33.6%. Moreover, the nano-carbon had a significant effect on soil loss controlling. The nano-carbon in alfalfa land showed the best effect for soil loss controlling, which was followed by caragana. Soybean land showed the highest soil loss. For the bare land (control) and alfalfa coverage, when the nano-carbon content was 1%, the lowest sediment yield was obtained; while for caragana, soybean and maize coverage, when the nano-carbon content was 0.5%, the sediment yield was the lowest. Based on the correlation analysis between nano-carbon and runoff and sediment yield, it could be concluded that nano-carbon has a significant impact on the experimental results. In the evaluation of soil and water loss control effect, the 0.5% nano-carbon had the obvious effect, which was similar with the 0.7% and 1.0% nano-carbon content, so considering the price, 0.5% nano-carbon content was appropriate on soil and water loss control in loess area. The results provide a guide for controlling soil water and nutrient loss on the sloping land. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Rain
Controlled terms:Conservation - Erosion - Risk management - Runoff - Security systems - Sediments - Soil conservation - Soil moisture - Soils - Vegetation - Water conservation
Uncontrolled terms:Arid and semi-arid areas - Chinese Academy of Sciences - Nano-carbon - Rainfall erosion - Runoff and sediment yields - Sloping land - Soil and water conservation - Vegetation coverage
Classification code:443.3 Precipitation - 444 Water Resources - 444.1 Surface Water - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 914.1 Accidents and Accident Prevention
Numerical data indexing:Percentage 5.00e-01%, Percentage 7.00e-01%, Age 5.00e+00yr, Percentage 1.00e+00%, Percentage 1.00e-01%, Percentage 2.87e+02%, Percentage 3.15e+01% to 3.36e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.016

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558516
Title:Modeling and validation on path loss of WSN in pig breeding farm
Authors:Zhu, Hong (1); Li, Shuang (1); Zheng, Limin (1, 2); Yang, Lu (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing; 100083, China; (2) Beijing Laboratory of Food Quality and Safety, China Agricultural University, Beijing; 100083, China
Corresponding author:Zheng, Limin(zhenglimin@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:205-212
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to build a path loss model and optimize the deployment of ZigBee nodes, in this study, how the characteristic affecting the wireless signal propagation in pig farm environment is evaluated. The research is based on ZigBee wireless sensor network technology. Depend on the environment of pig farm, we consider piggery wall and plant growing between piggeries as the two mainly barriers which affect the wireless signal propagation greatly. During the research, packet loss rate (PLR) of wireless signal and received signal strength indicator (RSSI) are the most important parameters being used to evaluate transmission characteristics. We chose direct ray model as the basic path loss model and designed three groups of experiment to measure the parameters used in the model. Firstly, we tested RSSI value changed with the distance between transmitter and receiver in the case of no obstacle for 12 times. Based on the data obtained by regression analysis, the path loss exponent value was 2.02 and the correlation coefficient was higher than 0.9. Secondly, the influence of barrier was taken in count. The thickness of piggery wall was 0.4 m and the antenna height was set at 1.2 m for avoiding the effect of other obstacles. By increasing the number of wall, the rate of packet loss obviously changed. Result showed that one or two walls have no influence on PLR value, but it turns to 17.75% when the number of walls increases to 3 and when the number of walls added to 5, with PLR value reaches 100%. The influence of wall is transformed into the wall attenuation factor that added into the path loss model, and its value is computed to be 2.64. There are plants growing between the piggeries, which can be divided into three groups, 40, 80 and 120 cm. We set 4 groups of antenna heights for each kind of plant, which is depending on their own height. At each antenna height, we tested RSSI value with the changes of distance between transmitter and receiver, and then get the varying pattern of plant attenuation factor with the antenna height based on the regression analysis. Results showed that plant attenuation factor decreased with the rising of the height of installing antenna. Finally, prediction path loss model with the wall attenuation factor 2.64 and the plant attenuation factor, we use multi stage function to express when the plant height is 40, 80 and 120 cm, were obtained. In order to test the accuracy and practicability of the model, the integrated experiments with both wall and plant as the barriers in the pig farm environment were investigated, and the model was verified according to the field-test result. In the model, the path loss exponent is 2.02 and the basic path loss value is 63.602 dBm and other parameters change with the plant height or antenna height. The model is a comprehensive model that can be used for predicting the path loss value of ZigBee wireless signal in the pig farm environment. On the basic of the prediction path loss model, we can optimize the node deployment for increasing the network coverage rate and connectivity. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Wireless sensor networks
Controlled terms:Antennas - Farms - Forecasting - Mammals - Models - Packet loss - Packet networks - Regression analysis - Sensor nodes - Transmitters - Zigbee
Uncontrolled terms:Correlation coefficient - Modeling and validation - Path loss - Pig breeding - Received signal strength indicators - Transmission characteristics - Transmitter and receiver - Wireless signal propagation
Classification code:722 Computer Systems and Equipment - 722.3 Data Communication, Equipment and Techniques - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2 Mathematical Statistics
Numerical data indexing:Decibel_milliwatts 6.36e+01dBm, Percentage 1.00e+02%, Percentage 1.78e+01%, Size 1.20e+00m, Size 4.00e-01m, Size 8.00e-01m
DOI:10.11975/j.issn.1002-6819.2017.02.028

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558519
Title:Simulation analysis of thermal properties of air enclosure covered with aluminum foil in wall of solar greenhouse
Authors:Zhang, Xiaodan (1); Xie, Jianming (1); Yu, Jihua (1); Lü, Jian (1)
Author affiliation:(1) College of Horticulture, Gansu Agricultural University, Lanzhou; 730070, China
Corresponding author:Xie, Jianming(xiejianming@gsau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:227-233
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:According to building structure and temperature variation of solar greenhouse wall, a two-dimensional steady flow and heat transfer model and a one-dimensional unsteady heat conduction model were established for simulation and study on the thermal performance of an air enclosure covered with aluminum foil, to explore suitable structure of the air enclosure in solar greenhouse wall insulation design. The results revealed that the wall surface covered with aluminum foil could effectively reduce radiation heat in the air enclosure; thermal resistance in the air enclosure increased with the rise of the enclosure height, and when the height reached 1.5 m, thermal resistance tended to be the same; when the enclosure thickness was less than 0.03 m, the air inside enclosure was in the stationary state, with heat conduction and thermal radiation as main heat transfer way, thermal resistance increased with the increasing thickness; when the thickness was more than 0.03 m, air natural connection in the enclosure was enhanced continuously, so convective heat transfer gradually replaced heat conduction, thermal resistance decreased with the increasing thickness. In wall insulation design of solar greenhouse, the suitable height and thickness of air enclosure covered with aluminum foil were 1.5 m and 0.03 m respectively. When temperature difference between inside and outside surface of the enclosure was 2-10 K in the simulation of heat preservation layer, average thermal conductivity was 0.047 W/(m· K), and thermal resistance was 0.70-0.58 K·m2/W in the air enclosure, heat preservation and heat insulation effect was equivalent to 0.81-0.67 m thickness of solid clay wall, or 0.55-0.45 m thickness of red brick wall, or 0.20-0.17 m thickness of coal cinder, or 0.06-0.05 m thickness of pearlite, or 0.03-0.025 m thickness of polystyrene board; When temperature difference was 10-20 K in the simulation of thermal conductivity layer, average thermal conductivity was 0.052 W/(m·K), and thermal resistance was 0.60-0.55 K·m2/W in the air enclosure, heat preservation and heat insulation effect was equivalent to 0.70-0.64 m thickness of solid clay wall, or 0.47-0.43 m thickness of red brick wall, or 0.17-0.16 m thickness of coal cinder, or 0.06-0.05 m thickness of pearlite, or 0.025-0.02 m thickness of polystyrene board. There are two types of solar greenhouse wall structures: 360 mm thickness of red brick wall + three 30 mm air enclosures covered with aluminum foil +120 mm thickness of red brick wall, 240 mm thickness of red brick wall + three 30 mm air enclosures covered with aluminum foil +240 mm thickness of red brick wall. The heat released to inside greenhouse form the two walls greatly increased than 480 mm thickness of red brick wall, but was not significantly different from the wall of the same structure composed by red brick wall and polystyrene board. Polystyrene board can be replaced with enclosure of this suitable structure in solar greenhouse wall design. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Thermal conductivity
Controlled terms:Aluminum - Aluminum foil - Brick - Enclosures - Greenhouses - Heat conduction - Heat convection - Heat resistance - Heat transfer - Insulation - Pearlite - Polystyrenes - Solar heating - Structural design - Temperature - Thermal conductivity of solids - Thermal insulation - Walls (structural partitions)
Uncontrolled terms:Convective heat transfer - Solar greenhouse - Temperature differences - Temperature variation - Thermal Performance - Two-dimensional steady flow - Unsteady heat conduction - Walls
Classification code:408.1 Structural Design, General - 408.2 Structural Members and Shapes - 413 Insulating Materials - 413.2 Heat Insulating Materials - 414.2 Brick Materials - 531.2 Metallography - 541.1 Aluminum - 641.1 Thermodynamics - 641.2 Heat Transfer - 657.1 Solar Energy and Phenomena - 815.1.1 Organic Polymers - 821.6 Farm Buildings and Other Structures
Numerical data indexing:Size 1.50e+00m, Size 1.70e-01m to 1.60e-01m, Size 2.00e-01m to 1.70e-01m, Size 2.40e-01m, Size 2.50e-02m to 2.00e-02m, Size 3.00e-02m to 2.50e-02m, Size 3.00e-02m, Size 3.60e-01m, Size 4.70e-01m to 4.30e-01m, Size 4.80e-01m, Size 5.50e-01m to 4.50e-01m, Size 6.00e-02m to 5.00e-02m, Size 7.00e-01m to 6.40e-01m, Size 8.10e-01m to 6.70e-01m, Temperature 1.00e+01K to 2.00e+01K, Temperature 2.00e+00K to 1.00e+01K, Thermal_Conductivity 4.70e-02W/m*K, Thermal_Conductivity 5.20e-02W/m*K
DOI:10.11975/j.issn.1002-6819.2017.02.031

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558494
Title:Revolving speed self-detecting control based on low-frequency signal injection for bearingless induction motor
Authors:Yang, Zebin (1); Li, Fangli (1); Chen, Zheng (1); Sun, Xiaodong (2)
Author affiliation:(1) College of Electrical and Information Engineering, Jiangsu University, Zhenjiang; 212013, China; (2) Automotive Engineering Research Institute, 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:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:41-47
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A bearingless induction motor has the advantages of no friction, no wear, high speed, ultra-high-speed operation, and so on, so it is widely used in the field of life science with the difficulties of periodic maintenance, the field of chemical industry, the semiconductor industry and other fields. However, the installation of mechanical speed sensor not only leads to the increase of axial length of the motor and the cost issue, but also limits the high-speed, ultra-high-speed development of bearingless induction motors. In order to eliminate the adverse effect of the mechanical speed sensor on the high speed running of the bearingless induction motor, to reduce the axial dimension of the bearingless induction motor, to promote the development of bearingless induction motors towards being small, low-cost and practical, exploring a new kind of speed self-detecting strategy is particularly important. A new speed sensorless control strategy based on low-frequency signal injection method was proposed to solve the problem of rotor speed identification in the operation of bearingless induction motor. This strategy has many advantages such as non ideal characteristics of the motor, not easy to introduce other high-frequency harmonic signal and simple structure, so it has strong applicability. With the bearingless induction motor fundamental model, through the response caused by low-frequency signal injection, rotor position deviation angle was constructed, which was adjusted further through the PI (proportion integration) controller, and then the rotational speed of the motor's air gap magnetic field was obtained. Then, the rotor speed was estimated. Using this speed self-detecting method, the simulation model of bearingless induction motor's speed sensorless vector control system was built in MATLAB/Simulink platform. The simulation included the rotor speed response, the radial offset in x and y axis, the torque response and the self-tracking ability to detect rotor speed when the rotor speed mutated. Simulation results showed that this method could fast track the rotor speed, besides, the rotor speed curve from the self-detecting and the actual speed curve could be fully consistent in a short time. In addition, the radial displacement obtained by the low-frequency signal injection method was compared with that obtained by the high-frequency signal injection method. The comparison results showed that the proposed method not only could reduce the maximum radial deviation of the rotor, but also enabled it at the center position in a shorter time. At the same time the starting torque of the motor was large. After the speed mutation, the control system also had a good tracking ability for a given speed, and a fast response, besides, stable error was very small. Finally, in the bearingless induction motor's control system experimental platform, the experiment was carried out using the proposed strategy. We selected the DSP TMS320F2812 as experiment control chip; a bearingless induction motor was used as a prototype, and the prototype parameters and simulation parameters were consistent. In order to more accurately compare the actual speed with the self-testing speed, the prototype was equipped with optical encoder disk. Test results showed that the self-detecting speed using the low-frequency signal injection method was more accurate than that using the high-frequency signal injection method, and the rotor center of mass offset distance using low-frequency signal injection method was smaller than that using high-frequency signal injection method. The results verify that the method has not only a good capability of speed online self-testing, but also a stable suspension operation of the rotor, and therefore the proposed method is effective and practical. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Sensorless control
Controlled terms:Chemical industry - Computer simulation - Control - Control systems - Electric motors - Induction motors - Magnetic devices - MATLAB - Models - Semiconductor device manufacture - Sensors - Speed - Vector control (Electric machinery)
Uncontrolled terms:Bearingless induction motor - High-frequency signal injection method - Low frequency signal injection method - Low-frequency signals - Non-ideal characteristics - Rotor speed identification - Speed sensorless control - Speed-sensorless vector control system
Classification code:705.3 Electric Motors - 705.3.1 AC Motors - 714.2 Semiconductor Devices and Integrated Circuits - 723.5 Computer Applications - 731.1 Control Systems - 731.2 Control System Applications - 805 Chemical Engineering, General
DOI:10.11975/j.issn.1002-6819.2017.02.006

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558524
Title:Mechanical properties and strength prediction of straw ash concrete
Authors:Zhang, Qiang (1); Li, Yaozhuang (1); Liu, Baohua (2); Xu, Zhisheng (1)
Author affiliation:(1) Institute of Disaster Prevention Science and Safety Technology, Central South University, Changsha; 410128, China; (2) College of Engineering, Hunan Agricultural University, Changsha; 410000, China
Corresponding author:Liu, Baohua(344419897@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:259-265
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to enhance the coagulation performance and reduce the energy consumption of the cement industry, part of the cement is replaced by straw ash to produce concrete. In this paper, biomass stalk ashes were acquired through microthermal incineration of rape stalks (500℃ for 5 h), and the stalk ash samples were obtained through grinding and screening of the preliminary ashes. Stalk ash was used as the concrete admixture to replace the same quantity of cement to produce experimental specimens, different amounts of rape stalk ash admixtures and concrete water-binder ratios were selected as the affecting variables of concrete property, and the effects of stalk ash on the concrete were discussed. The results indicated that when the amount of rape stalk ash admixture was 5%, the splitting tensile strength property of stalk ash concrete was 12% lower and the compression resistance was only 4% lower than normal concrete (28 d); when the amount of rape stalk ash admixture was 10%, the splitting tensile strength property of rape stalk ash concrete was 25% lower and the compression resistance was 8% lower than normal concrete; when the amount of admixture was 15%, the compression resistance was 13% lower than normal concrete, which met the use requirement of structural concrete (Code for Design of Reinforced Concrete Structures); and when the amount of rape stalk ash admixture was 20%, the splitting tensile strength property of rape stalk ash concrete was 45% lower and the compression resistance was 23% lower than normal concrete. And the rate of descent accelerated when the amount of rape stalk ash admixture exceeded over 20%. The experiments proved that stalk ash was somewhat water-absorbing, and therefore the best water-binder ratio of stalk ash concrete fell in the range of 0.45-0.55, and the best water-binder ratio was 0.5 for rape stalk ash concrete. The relationship between straw ash concrete's tensile and compressive properties was given, which was further verified by comparing with other concrete's tensile and compressive strength formulas including American Concrete Association's recommended formula, Yuan Biao's empirical formulas and Wang Dehui's empirical formulas. The splitting tensile strength ratio could be concluded from the fitting of experimental data, and the fitting result was good. Due to the lack of experimental data of straw ash concrete, however, the next step of the research focused on the verification of the reasonability of this relationship. The method of the random function was introduced to conduct the random sampling on the experimental data. And the prediction method of wavelet neural network was used to improve the training samples, and automatically modify the network structure parameters and predict stalk ash concrete's experimental data. Then, the predicted data were used for verifying the tensile and compressive formulas proposed in this study and the predicted and the test data were compared for error calculation. The wavelet neural network forecast data indicated that the maximum forecast error was 8% and the minimum was only 0.8%, so it was appropriate to forecast the mechanical property of stalk ash concrete. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Concrete additives
Controlled terms:Binders - Bins - Cement industry - Cements - Compressive strength - Concretes - Energy utilization - Forecasting - Incineration - Mechanical properties - Neural networks - Reinforced concrete - Screening - Straw - Tensile strength
Uncontrolled terms:Coagulation performance - Compression resistance - Compressive properties - Experimental specimens - Rape straws - Splitting tensile strength - Structural concretes - Wavelet neural networks
Classification code:412 Concrete - 412.1 Cement - 525.3 Energy Utilization - 694.4 Storage - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 821.5 Agricultural Wastes - 951 Materials Science
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.20e+01%, Percentage 1.30e+01%, Percentage 1.50e+01%, Percentage 2.00e+01%, Percentage 2.30e+01%, Percentage 2.50e+01%, Percentage 4.00e+00%, Percentage 4.50e+01%, Percentage 5.00e+00%, Percentage 8.00e+00%, Percentage 8.00e-01%, Time 1.80e+04s
DOI:10.11975/j.issn.1002-6819.2017.02.036

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558511
Title:Wheat canopy spectral reflectance feature response to heavy metal copper and zinc stress
Authors:Wang, Hui (1, 3); Zeng, Lusheng (1); Sun, Yonghong (2); Zhang, Jinheng (3); Guo, Qingzeng (3); Sun, Fangli (3); Song, Chaoyu (2); Chen, Jianmei (2)
Author affiliation:(1) College of Resources and Environment, Qingdao Agriculture University, Qingdao; 266109, China; (2) Qingdao Academy of Agriculture Science, Qingdao; 266100, China; (3) School of Environment and Safety Engineering, Qingdao Science and Technology University, Qingdao; 266042, China
Corresponding author:Zhang, Jinheng(zjh-nhl@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:171-176
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid development of economy and modern industrial and agriculture, more and more heavy metals such as cadmium, copper and zinc come into environment. Heavy metals are not only polluting soil, water and air, but also affecting crops growth and the yield, and affecting food security and human health by food chain. It was reported that heavy metal contamination of arable land in China has reached 20 million hm2, accounting for the country's total cultivated area of 1/6. Therefore, many researchers pay more attention to the heavy metal pollution problems increasingly. At present, researchers usually use chemical and biological methods to test the pollution extent of different heavy metals. Those methods are time consuming and even cause the second environmental pollution. Using spectral analysis to monitor the heavy metals stress on crops is an innovative approach. However, the effect of heavy metal pollution on crops spectrum is still in the exploration stage. Because of the effect of different factors such as plants and environment, the diagnosis of heavy metal stress mechanism on plant is still unclear. The crop tolerance at different growth stages are different from heavy metals, therefor, to explore the critical concentration of different heavy metals stress on crops at the different growth stages has certain practical significance. In order to monitor the crop stress of heavy metal pollution rapidly, under open field plot conditions and using canopy spectral analysis, the canopy spectral features of wheat at different stages of tillering, jointing and heading were studied at the different treatments of Cu (0, 100, 300, 600 and 900 mg/kg) and Zn (0, 250, 500, 750 and 1 000 mg/kg), according to the national soil quality standard (GB15618-1995) of China. The experiment was conducted in the experimental field of Qingdao Academy of Agricultural Sciences in Chengyang District of Qingdao City, in October 2014 to June 2015. The total area of the test plot was 180 m2, and the test soil type is Shajiang black soil, with the pH value of 6.85, the organic matter content of 22.6 g/kg, nitrogen content of 94.6 mg/kg, available phosphorus content of 77.5 mg/kg, the available potassium content of 113 mg/kg, copper content of 28.1 mg/kg and zinc content of 73 mg/kg. The experiment was conducted by traditional management. The results indicated that at different concentration treatments of copper (Cu) and zinc (Zn), the canopy spectral reflectance in the visible band (350-760 nm) increased obviously with the concentration treatments increasing of Cu and Zn at the tillering and jointing stages of wheat, however, the canopy spectral reflectance of near infrared band (760-900nm) reduced with the increasing concentration of Cu and Zn treatment levels. Wheat canopy spectral reflectance appeared red edge position and red valley position shifting toward short wavelength called "blue shift" at tillering stage of wheat under the different concentration treatments of Cu and Zn. At the tillering stage of wheat, copper treatments of 600 and 900 mg/kg and at the jointing stage copper treatment of 900 mg/kg, the red edge normalized index value (NDVI705) were less than 0.2. At the tillering stage, zinc treatments of 750 and 1 000 mg/kg, the red edge normalized index value (NDVI705) was less than 0.2. This research also indicated that the wheat canopy spectral features response obviously to the threshold values concentration treatment level of Cu were between 300 and 600 mg/kg, and Zn were between 500 g and 750 mg/kg. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Copper
Controlled terms:Agriculture - Chemical analysis - Chemical contamination - Crops - Food supply - Heavy metals - Infrared devices - Metal analysis - Plants (botany) - Pollution - Quality control - Reflection - Remote sensing - Soil pollution - Soils - Spectrum analysis - Wavelength - Zinc
Uncontrolled terms:Canopy spectral reflectance - Chemical and biologicals - Concentration threshold - Different growth stages - Environmental pollutions - Heavy metal contamination - Traditional management - Wheat
Classification code:483.1 Soils and Soil Mechanics - 531 Metallurgy and Metallography - 544.1 Copper - 546.3 Zinc and Alloys - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 822.3 Food Products - 913.3 Quality Assurance and Control
Numerical data indexing:Area 1.80e+02m2, Size 3.50e-07m to 7.60e-07m, Size 7.60e-07m to 9.00e-07m
DOI:10.11975/j.issn.1002-6819.2017.02.023

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558508
Title:Numerical analysis for force at embedded end of sand barrier under wind loads
Authors:Sun, Hao (1); Liu, Jinhao (1); Huang, Qingqing (1)
Author affiliation:(1) School of Technology, Beijing Forestry University, Beijing; 100083, China
Corresponding author:Liu, Jinhao(liujinhao@vip.163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:148-154
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Inserted depth is an important parameter in sand fence engineering. In order to provide a theoretical support for inserted depth of sand fence, the sand fence with different porosity was studied by using LES method. Five kinds of sand fence were selected as the research objects with the porosity of 0, 20%, 40%, 60% and 80%. The height of sand fence was 50 mm. Boundary condition was of great importance to the simulation of the flow structure around the sand fence, the large eddy model (LES) was employed as the turbulence model. The gas phase had been simplified with the influence of sand particles ignored. It was treated as incompressible gas, and its flow was assumed to be in transition state. The velocity at inlet of calculation domain followed the logarithm distribution and the friction velocity was 0.5 m/s. The SIMPLIC method was employed for flow field prediction. Ten layers were arranged near wall and the height of the first layer was 0.01 mm, and yplus was less than 1. The top boundary of calculation domain was slip wall boundary, and the bottom was nonslip wall boundary. The turbulence numerical results for sand fence with the porosity 0 were compared with the experimental results of a similar study that was conducted in a blowing sand wind tunnel at the Key Laboratory of Desert and Desertification of Chinese Academy of Sciences. The particle image velocimetry (PIV) was employed to determine mean velocity and the turbulence fields were calculated by the velocity. The numerical model was well verified. Then, the variation of bending moment and shear force with porosity and the flow structure around the fence were analyzed. The results showed that the bending moment and shear force on the embedded end of sand fence without pores was much higher than that for the sand fence with pores under the sudden air flow with same velocity, and its maximum bending moment and shear force on the embedded end were 2 and 1.5 times of that with 40% porosity, and were 16.5 and 14.45 times of that with 80% porosity. The maximum bending moment and shear force on the embedded end decreased with increasing porosity. The bending moment and shear force decreased greatly under continuous wind forces. When the porosity of sand fence was 0, its maximum bending moment and shear force on the embedded end was about 9.4 and 6.9 times of the mean under the continuous wind forces. When the porosity of sand fence was 80%, its maximum bending moment and shear force on the embedded end was about 2.3 and 2.5 times of the mean under the continuous wind forces. The size of the main vortex behind the sand fence decreased with the increase of the porosity. Large eddy had a stronger resistance to its movement change, causing the lager bending moment and shear force at the embedded end of sand fence with 0 porosity compared to the sand fence which has porosity. When the porosity was less than 50%, there was no obvious main vortex structure in the rear of the sand fence and its flow structure was similar to that for the single plate. The flow structure around the sand barrier with closed porosity had similar appearance, and it could be divided into 2 groups by the porosity of 50%, and the stress in each of the group had the similar varying characteristics. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Sand
Controlled terms:Air - Bending moments - Fences - Flow structure - Large eddy simulation - Numerical methods - Porosity - Shear flow - Turbulence models - Velocity - Velocity measurement - Vortex flow - Wind tunnels
Uncontrolled terms:Chinese Academy of Sciences - Maximum bending moments - Numerical results - Particle image velocimetries - Porous fence - Sand fixation - Turbulence fields - Vortex structures
Classification code:408.2 Structural Members and Shapes - 483.1 Soils and Soil Mechanics - 631 Fluid Flow - 631.1 Fluid Flow, General - 651.2 Wind Tunnels - 804 Chemical Products Generally - 921 Mathematics - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids - 943.3 Special Purpose Instruments
Numerical data indexing:Percentage 2.00e+01%, Percentage 4.00e+01%, Percentage 5.00e+01%, Percentage 6.00e+01%, Percentage 8.00e+01%, Size 1.00e-05m, Size 5.00e-02m, Velocity 5.00e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.02.020

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558495
Title:Effect of structural parameters on lubrication performance of floating ring bearing and ring speed ratio in turbocharger
Authors:Li, Jiaqi (1); Ni, Jimin (1); Shi, Xiuyong (1); Xu, Xiaochuan (1); Liu, Yue (1); Li, Dongdong (1); Chen, Zhenbin (2)
Author affiliation:(1) School of Automotive, Tongji University, Shanghai; 201804, China; (2) Colleague of Mechanical and Electrical Engineering, Hainan University, Danzhou; 571737, China
Corresponding author:Ni, Jimin(njmwjyx@hotmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:48-55
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Turbochargers are widely used in internal combustion engines. The floating ring bearing is the most important part in the turbocharger, which is composed of inner film and outer film. The floating ring bearing can reduce the frictional power and oil film temperature. In the past, the lubrication performances of the floating ring bearing were analyzed without considering the heat transfer among the shaft, floating ring and bearing block. Furthermore, some researchers analyzed the lubrication performance of floating ring and the ring speed ratio separately. In reality, there exists heat transfer among the shaft, floating ring and bearing block and this part of heat will directly influence the lubrication performance of the floating ring. Besides, the change of the structural parameters may decrease ring speed ratio, which maybe is unfavorable to the practical operation if it is too small, and the change of the ring speed ratio may also influence the lubrication performance. So there exists a strong coupled relationship between the lubrication performance and ring speed ratio, and they can be studied more comprehensively and systematically with the change of structural parameters. The lubrication performance of floating ring bearing and the floating ring speed ratio in turbocharger were studied by considering the heat transfer among the shaft, floating ring and bearing block. Based on the Reynolds equation and the floating ring balance equation, the lubrication model of floating ring bearing was established. The Reynolds equation was solved by the finite difference method. The thermal deformation of the floating ring bearing was calculated by the thermal deformation equation. Comparative analysis on the influence of structural parameters on lubrication performance of floating ring bearing and floating ring speed ratio was performed, and the parameters included inner film clearance, outer film clearance, inner circle radius and outer circle radius. Results showed the effect and affecting level of structural parameter on lubrication performance and floating ring speed ratio should be considered comprehensively. The ring speed ratio decreased with the increase of inner film clearance. Compared with that inner film clearance is 0.02 mm, the ring speed ratio decreased 23% when inner film clearance is 0.04 mm. The inner film temperature, the outer film temperature decreased and the total friction power loss slightly increased with the increase of inner film clearance. The lubrication performance and ring speed ratio are ideal when inner film clearance is 0.03 mm. Compared with that outer film clearance is 0.04 mm,the ring speed ratio increased more than 30%. The outer film temperature decreased with the increase of outer film clearance. The higher the rotation speed, the greater the decrease amplitude of the outer film temperature. The smaller the inner circle radius, the smaller the floating ring speed ratio, and the smaller the inner film temperature, outer film temperature and total friction power loss. So the lubrication performance of the floating ring bearing will be improved with the decrease of the inner circle radius. The ring speed ratio decreased with the increase of the outer circle radius. But the inner film temperature, the outer film temperature increased, the total friction power loss and total oil leakage flowrate changed less than 5% with the increase of the outer circle radius. The outer circle radius has little effect on the lubrication performance of the floating ring bearing. Compared with the adjustment of the outer circle radius, it is more effective to improve the lubrication performance of floating ring bearing with the adjustment of the inner circle radius. There is a good agreement between the results predicted by the calculation model in this paper and some published experimental data. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Speed
Controlled terms:Bearings (structural) - Compressors - Deformation - Finite difference method - Friction - Heat transfer - Internal combustion engines - Lubrication - Models - Reynolds equation - Superchargers - Temperature - Tribology - Turbomachinery
Uncontrolled terms:Comparative analysis - Floating ring bearings - Friction power loss - Lubrication performance - Oil film temperature - Speed ratio - Structural parameter - Thermal deformation equations
Classification code:401.1 Bridges - 607.2 Lubrication - 612.1 Internal Combustion Engines, General - 618.1 Compressors - 641.1 Thermodynamics - 641.2 Heat Transfer - 921.2 Calculus - 921.6 Numerical Methods - 931 Classical Physics; Quantum Theory; Relativity
Numerical data indexing:Percentage 2.30e+01%, Percentage 3.00e+01%, Percentage 5.00e+00%, Size 2.00e-05m, Size 3.00e-05m, Size 4.00e-05m
DOI:10.11975/j.issn.1002-6819.2017.02.007

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558525
Title:Spatial-temporal variations of dematerialization of inputs and environmental risk reduction in intensive agricultural region
Authors:Fu, Yonghu (1, 2); Liu, Liming (1); Wang, Jiasheng (1); Ye, Jinwei (1); Guo, Yun (1)
Author affiliation:(1) College of Resources and Environment, China Agricultural University, Beijing; 100193, China; (2) Law School, Huaihai Institute of Technology, Lianyungang; 222005, China
Corresponding author:Liu, Liming(liulm@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:266-275
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Evaluation of the agricultural land use environmental efficiency is an essential issue for building sustainable land use patterns with fewer agricultural inputs and lower environmental risk. In this paper, 1) nitrogen footprint (N footprint) and grey water footprint (GWF) were used to evaluate environmental effects (reactive nitrogen emission and non-point source pollution) of agricultural land use system at the regional scale; 2) the window type slacks-based measure (SBM) model based on undesirable outputs (pollution N footprint and non-point resource pollution GWF) was applied to calculate environmental efficiency of the agricultural land use system; 3) inputs and environmental risk reduction potentials were computed and evaluated based on the dual perspective of reactive nitrogen emission and non-point source pollution in an intensive agricultural area. The Qingpu District was selected as a study case for this approach. The results mainly show that: 1) There were significant spatial-temporal differences in using pollution N footprint and non-point source pollution GWF within Qingpu District. The pollution N footprint of agricultural land use system was between 2 805.59 t and 3 505.68 t in the period of 2006-2013. The annual total grey water volume for agricultural non-point source pollution ranged from 134 026.58×104m3to 152 833.70×104m3during the years 2006-2013, and its average value was 144 969.00×104m3. The negative effect of water environment under agricultural land use process was assessed by the indicator of water environmental pressure (WEP) at county level. The average value of WEP of agricultural land use system was 5.74. The high value of WEP suggested that the negative environmental effect of agricultural production increased. The spatial distribution of pollution N footprint and non-point source GWF in Qingpu District was higher value in the west but lower in the east in general. 2) According to the results of SBM-undesirable model, overall environmental efficiency of agricultural land use in Qingpu District remained at a low level, and its average efficiency was 0.669 in the period of 2006-2013. 3) The models of potential percentage reduction and potential reduction scale were built for evaluation of dematerialization and environmental risk reduction respectively based on the dual perspective of reactive nitrogen emission and non-point source pollution. The annual average percentage reduction of labor, fertilizer, mechanical power, pollution N footprint and non-point source pollution GWF were 32.21%, 25.70%, 38.21%, 12.32% and 32.18%, respectively. The average reductions of labor, fertilizer, mechanical power, pollution N footprint and non-point source pollution GWF were 8 104 people, 4 501.59 t, 27 928.44 kW, 381.04 t and 52 046.88×104m3during the years 2006-2013. Xiang Huaqiao had the highest percentage of environmental risk reduction among the 11 towns, while Baihe and Liantang had a larger scale of emission reductions at the same time. Therefore, Baihe and Liantang should be the key areas for agricultural resources conservation and pollutant emissions control within Qingpu District. The findings of this study can provide scientific supports for regional agricultural planning and policy-making. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Water pollution
Controlled terms:Agriculture - Efficiency - Emission control - Fertilizers - Land use - Nitrogen - Pollution - Risk assessment
Uncontrolled terms:Environmental efficiency - Environmental risks - Grey waters - Low input - Nitrogen footprints
Classification code:403 Urban and Regional Planning and Development - 451.2 Air Pollution Control - 453 Water Pollution - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering - 914.1 Accidents and Accident Prevention
Numerical data indexing:Percentage 1.23e+01%, Percentage 2.57e+01%, Percentage 3.22e+01%, Percentage 3.82e+01%, Power 9.28e+05W
DOI:10.11975/j.issn.1002-6819.2017.02.037

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558531
Title:Compatibilizer improving properties of tea dust/polylactic acid biomass composites
Authors:Gong, Xinhuai (1, 2); Xin, Meihua (1); Li, Mingchun (1); Yuan, Hongxing (1); Xie, Jiansheng (1)
Author affiliation:(1) Engineering Research Center of Environment-Friendly Functional Materials, College of Material Science and Engineering, Huaqiao University, Xiamen; 361021, China; (2) Fujian Provincial Key Laboratory of Eco-Industrial Green Technology, Ecology and Resources Engineering College, Wuyi University, Wuyishan; 354300, China
Corresponding author:Li, Mingchun(mcli@hqu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:308-314
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the increasing scarcity of oil resources and the aggravation of white pollution, environmentally friendly biodegradable materials have become a topic of great interest in research and development. Among the biodegradable polymers, polylactic acid (PLA) is one of the most studied and promising aliphatic polyesters derived from starch by microbial fermentation, which offers excellent properties such as high strength, good transparency and biodegradability. However, PLA also has disadvantages of poor toughness and high cost. PLA is often reinforced with natural fibers like wood flour, bamboo flour, sisal, coir and hemp to reduce the production cost. Among the various natural fibers, tea fiber is cheap and widely available especially in China. The worldwide consumption of tea is about 4.5 million tons annually, and it always ends up with lots of waste tea leaves, stalks and dusts during the process of tea production and consumption. The tea residue to use as organic filler in polymer composites shows a great prospect because of its lignocelluloses behaviors and low cost. To our knowledge, there have been few researches about the biodegradable composites by using waste tea residue as organic filler so far. However, the moisture absorption tendency and poor interfacial bonding properties of the fibers are the main drawbacks of PLA/natural fiber biomass composites. Many researches focused on surface modification of natural fibers through different methods such as mercerization, silane treatment and isocyanate treatment to improve the compatibility between natural fiber and PLA matrix. Melting grafting copolymerization is a novel modification technology for plastics, the use of PLA grafted with glycidyl methacrylate (GMA) is a relatively efficient strategy to improve both the interface adhesion and toughness of natural fiber/PLA biomass composites. In order to decrease the cost of PLA, and expand its applicability, and also to make full use of the waste tea residue, tea dust (TD) was blended with PLA to prepare environmental friendly TD/PLA composites by injection molding. PLA grafted with glycidyl methacrylate (GMA-g-PLA) was synthesized by melt grafting PLA with GMA using dicumyl peroxide as initiator, the graft copolymer was confirmed by FTIR (Fourier transform infrared spectrum) and1H-NMR (H nuclear magnetic resonance), and the influences of GMA-g-PLA addition on the mechanical, thermal and moisture resistance properties of TD/PLA composite were investigated. GMA grafting onto PLA was confirmed by FTIR and11H-NMR spectroscopic technology. The phase morphology, thermal stability, moisture resistance and mechanical properties of TD/PLA composites compatibilized with GMA-g-PLA were improved compared with those of the composites without adding compatibilizer, as characterized by scanning electron microscopy, thermogravimetric analysis, water adsorption test and using a universal materials tester, respectively. The GMA was successfully grafted onto PLA, which was confirmed by the FTIR and1H-NMR technology, and the grafted GMA content was 4.88% calculated by1H-NMR analysis. The addition of GMA-g-PLA in the biocomposites obviously improved the mechanical, thermal and water adsorption properties of TD/PLA composites, which is attributed to the greater compatibility between TD and PLA matrix. The TD/PLA biomass composite with 10% (mass fraction) GMA-g-PLA showed the optimum mechanical properties, with an improvement of 43.8% in tensile strength, 42.1% in flexural strength, 24.1% in notched impact strength, 26.5% in tensile modulus, 10.4% in flexural modulus and 26.1% in elongation at break, respectively. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Fiber bonding
Controlled terms:Acrylic monomers - Biodegradability - Biodegradable polymers - Biomass - Compatibilizers - Composite materials - Costs - Driers (materials) - Dust - Fibers - Filled polymers - Fillers - Fourier transform infrared spectroscopy - Grafting (chemical) - Hemp fibers - Impact strength - Injection molding - Mechanical properties - Moisture - Natural fibers - Nuclear magnetic resonance - Peroxides - Petroleum deposits - Polyesters - Radioactive waste disposal - Reinforced plastics - Scanning electron microscopy - Surface treatment - Tensile strength - Thermogravimetric analysis - Wood
Uncontrolled terms:Biodegradable composites - Fourier transform infrared spectra - Grafting copolymerization - Melt grafting - Poly lactic acid - Production and consumption - Research and development - Spectroscopic technologies
Classification code:451.1 Air Pollution Sources - 461.1 Biomedical Engineering - 512.1 Petroleum Deposits - 622.5 Radioactive Wastes - 801 Chemistry - 801.2 Biochemistry - 802.2 Chemical Reactions - 803 Chemical Agents and Basic Industrial Chemicals - 804.1 Organic Compounds - 811.2 Wood and Wood Products - 815.1 Polymeric Materials - 815.1.1 Organic Polymers - 817.1 Polymer Products - 819.1 Natural Fibers - 911 Cost and Value Engineering; Industrial Economics - 951 Materials Science
Numerical data indexing:Percentage 1.00e+01%, Percentage 1.04e+01%, Percentage 2.41e+01%, Percentage 2.61e+01%, Percentage 2.65e+01%, Percentage 4.21e+01%, Percentage 4.38e+01%, Percentage 4.88e+00%
DOI:10.11975/j.issn.1002-6819.2017.02.043

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558499
Title:Chlorination with lateral flushing controlling drip irrigation emitter clogging using reclaimed water
Authors:Song, Peng (1); Li, Yunkai (1); Li, Jiusheng (2); Pei, Yiting (1)
Author affiliation:(1) College of Water Resources and Civil Engineering, China Agricultural University, Beijing; 100083, China; (2) State key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100048, China
Corresponding author:Li, Yunkai(liyunkai@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:80-86
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Emitter bio-clogging has a close relation with the formation and growth of its internal clogging substances - the biofilms attached in the reclaimed water drip irrigation system. Chlorination with lateral flushing is one of the most effective measures to control the formation of biofilms within emitter, by using the chlorine to inhibit microbial growth and the shearing force to scour the clogging substances out of the system. Based on these, a field experiment using the reclaimed water treated with the cyclic activated sludge system (CASS) technology was carried out in the sewage treatment plant in order to study the controlling effects of 3 types of modes on emitter clogging, which were lateral flushing (flushing velocity was 0.45 m/s), chlorination (chlorination concentration was 5.00 mg/L) and chlorination with lateral flushing; chlorine and lateral flushing frequency were both once every 2 weeks (the time interval was 50 h). The result showed that chlorination with lateral flushing could effectively reduce the microbial contents in the attached biofilms within the emitters, as the phospholipid fatty acids (PLFAs) microbial content was 18.8 μg at the second sampling, which was decreased by 52.2%, 44.2%, 73.2% compared with lateral flushing, chlorination and CK (the control, neither lateral flushing nor chlorination) treatment, respectively, and the secreted sticky extracellular polymeric substances (EPS) content was also reduced by 28.0%, 22.9%, 63.9%, respectively. EPS content was 0.47 mg at the second sampling, so that the total amount of clogging substances within emitter decreased by 47.4%, 43.1%, 69.1% with the joint action of the microorganisms and the secreted viscous polymer, thus making the emitter discharge ratio variation (Dra) and coefficient of uniformity (CU) improved by 40.0% and 53.0% respectively at the maximum, and the CU was kept more than 70%. The PLFAs microbial content and EPS content increased from the inlet of the drip irrigation lateral for the same treatment. The results also indicated that the content of EPS in the emitter did not show the same trend in comparison with the chlorination and lateral flushing. The effect of lateral flushing on the secretion of viscous EPS was better than that of chlorination treatment for the head part of emitter, but it was opposite for the middle and end part of emitter. Chlorination and lateral flushing could kill microorganisms, the species of microorganisms marked by PLFAs decreased obviously, and the microbial community structure in the emitter changed, but the types of dominant microorganisms were not changed. Thus it was more likely to delay chlorination starting time, and when the emitter Dra was reduced to 80%, chlorination could still reach a satisfactory controlling effect. Chlorination with the lateral flushing kills microorganisms and scours away the clogging substances at the same time, which makes the biofilm continued to grow and detach. But microorganisms produce resistance, and the production of resistant bacteria increases microbial activity to adapt to the changing external environment. So chlorination with lateral flushing increased microbial activity significantly by 36.5%, 29.0% and 15.7%, respectively, compared with lateral flushing, chlorination and CK treatment. It also decreased the recovery effect on emitter clogging gradually. In general, chlorination with lateral flushing can effectively control emitter clogging for drip irrigation using the reclaimed water treated with CASS. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Chlorination
Controlled terms:Activated sludge process - Biofilms - Chemicals removal (water treatment) - Chlorine - Fatty acids - Irrigation - Microorganisms - Phospholipids - Polymers - Reclamation - Sewage treatment plants - Water treatment - Water treatment plants
Uncontrolled terms:Activated sludge systems - Coefficient of uniformity - Emitter clogging - Extracellular polymeric substances - Lateral flushing - Microbial community structures - Phospholipid fatty acids - Re-claimed water
Classification code:445.1 Water Treatment Techniques - 452.2 Sewage Treatment - 461.9 Biology - 462.5 Biomaterials (including synthetics) - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 815.1 Polymeric Materials - 821.3 Agricultural Methods
Numerical data indexing:Age 3.84e-02yr, Mass 1.88e-08kg, Mass 4.70e-07kg, Mass_Density 5.00e-03kg/m3, Percentage 1.57e+01%, Percentage 2.29e+01%, Percentage 2.80e+01%, Percentage 2.90e+01%, Percentage 3.65e+01%, Percentage 4.00e+01%, Percentage 4.31e+01%, Percentage 4.42e+01%, Percentage 4.74e+01%, Percentage 5.22e+01%, Percentage 5.30e+01%, Percentage 6.39e+01%, Percentage 6.91e+01%, Percentage 8.00e+01%, Percentage 7.00e+01%, Percentage 7.32e+01%, Time 1.80e+05s, Velocity 4.50e-01m/s
DOI:10.11975/j.issn.1002-6819.2017.02.011

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558513
Title:Geostatistical models of soil organic carbon density prediction based on soil hyperspectral reflectance
Authors:Liu, Yanfang (1, 2, 3); Song, Yuling (1, 2, 3); Guo, Long (4); Chen, Yiyun (1, 2, 5, 6); Lu, Yannian (1, 2, 3); Liu, Yi (1, 2, 3)
Author affiliation:(1) School of Resource and Environmental Science, Wuhan University, Wuhan; 430079, China; (2) Key Laboratory of Geographic Information Systems, Ministry Education, Wuhan University, Wuhan; 430079, China; (3) Key Laboratory of Digital Mapping and Land Information Application Engineering, National Administration of Surveying, Mapping and Geo-information, Wuhan; 430079, China; (4) College of Resource and Environment, Huazhong Agricultural University, Wuhan; 430070, China; (5) Collaborative Innovation Center of Geospatial Technology, Wuhan University, Wuhan; 430079, China; (6) Suzhou Institute of Wuhan University, Suzhou; Jiangsu; 215123, China
Corresponding author:Chen, Yiyun(chenyy@whu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:183-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The availability of soil organic carbon density (SOCD) information is of great importance for the development of ecological agriculture and the study of global climate change. Compared with traditional laboratory analysis, Visible and near-infrared (VNIR) reflectance spectroscopy has proven to be a rapid, non-destructive and cost effective method for estimating a variety of soil properties. It has got rapid development and has been applied in the field of soil research. In the prediction of soil properties by using spectral information, however, traditional linear regression models often ignore the spatial heterogeneity and dependency of soil, and fail to consider the spatial structure of the error term. With the aims to fill the current gap, a total of 232 topsoil samples were collected in Jianghan Plain with their spectral reflectance and SOCD measured. Partial least squares regression (PLSR), ordinary kriging (OK), co-kriging (COK), and regression kriging (RK) were used to estimate SOCD by using differently pre-treated spectral reflectance. Due to the facts that spectral pretreatments are crucial to reduce the physical variability and particle size effect, and are helpful to remove both additive and multiplicative effects in the spectra, five combinations of spectral pretreatments were utilized while predicting SOCD with PLSR. They were Savitzky-Golay smoothing (S-G), S-G + Multiplicative Scatter Correction (MSC), S-G+Standard Normal Variate (SNV), S-G + first derivative (1st), S-G + second derivative (2nd), S-G+1st+MSC, S-G+2nd+MSC, S-G+1st+SNV, S-G+2nd+SNV. The prediction capabilities of the models were evaluated by R2, root mean squared error (RMSE), and ratio of performance to deviation (RPD). Results showed that the RK approach which utilized soil spectra information outperformed the others, with the highest R2-Pred 0.617 and RPD 1.614, and the lowest RMSEP 0.865 kg/m2. PLSR took the second place with R2-Pred 0.605, RPD 1.523 and RMSEP 0.917 kg/m2, which was also acceptable for SOCD prediction. COK and OK generally failed in the predictions of SOCD, with R2-Pred equaled to 0.007 and 0.004, RPD equaled to 0.903 and 0.874 and RMSEP equaled to 1.547 and 1.597 kg/m2, respectively. Results indicated that the RK model, which considered both the spectral reflectance and the spatial structure of the error term of multivariate linear regression model can improve the prediction accuracy of SOCD. The fundamental reasons could be that soil spectra are comprehensive reflections of soil properties and those environmental factors that influence the formation of soil. Therefore, soil spectra are related with the variation of SOCD, and could be helpful in the prediction of SOCD. Besides, the optimal spectral pretreatment for PLSR modelling of SOCD is the combination of smoothing, first-order derivation and SNV. In summary, soil reflectance spectra in the visible and near-infrared region (350-2 500 nm) could serve as an effective proxy variable for SOCD estimation. Given that soil VNIR reflectance spectra are easy and quick to measure, and the measurement is also environmentally friendly, we would like to argue that soil spectral reflectance could serve as an ideal auxiliary variable for the spatial interpolation of SOCD. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Soils
Controlled terms:Climate change - Cost effectiveness - Errors - Forecasting - Infrared devices - Interpolation - Least squares approximations - Linear regression - Mean square error - Models - Organic carbon - Particle size - Reflection - Regression analysis - Spectrum analysis
Uncontrolled terms:Co-Kriging - Hyperspectral reflectance - Multiplicative scatter correction - Multivariate linear regression model - Partial least squares regression - Partial least squares regressions (PLSR) - Regression-kriging - Soil organic carbon densities
Classification code:443.1 Atmospheric Properties - 483.1 Soils and Soil Mechanics - 804.1 Organic Compounds - 911.2 Industrial Economics - 921.6 Numerical Methods - 922.2 Mathematical Statistics
Numerical data indexing:Size 3.50e-07m to 2.50e-06m, Surface_Density 1.55e+00kg/m2, Surface_Density 1.60e+00kg/m2, Surface_Density 8.65e-01kg/m2, Surface_Density 9.17e-01kg/m2
DOI:10.11975/j.issn.1002-6819.2017.02.025

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558527
Title:Analysis of ecological land pattern evolution and ecosystem service value in Bashang plateau
Authors:Wu, Aibin (1); Zhao, Yanxia (1)
Author affiliation:(1) Institute of Geographical Sciences, Hebei Academy of Sciences, Shijiazhuang; 050021, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:283-290
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Ecological land is of great significance in safeguarding important ecological processes and providing essential ecosystem services, and the classification and evaluation of the ecosystem services of ecological land have become increasingly important in recent years. In order to change the trend of ecological land loss caused by blind economic development and to improve the regional pattern for ecological security, it is necessary to study the rational allocation of the quantitative structure and the spatial patterns of ecological land. Based on land use data of Bashang plateau in 1990, 1995, 2000, 2005, 2010 and 2015, GIS (geographic information system) technology was used to analyze ecological land pattern evolution and ecosystem service values of Bashang plateau. The results were as follows: (1) The ecological land in Bashang plateau was classified into 4 types (forest, grassland, wetland and other ecological land) and 15 sub-types; the quantity of ecological land decreased from 904 500 to 881 800 hm2during 1990- 2015 due to the decreased grassland and wetland and the increased forest and other ecological land. The quantities of forest and other ecological land increased from 275 000 and 8 300 to 324 900 and 11 300 hm2respectively, and meanwhile the quantities of grassland and wetland decreased from 501 500 and 119 700 to 437 300 and 108 300 hm2respectively. (2) The transfer rates of forest, other ecological land, grassland and wetland were 1.45%, 0.73%, -0.51% and -0.38% from 1990 to 2015, respectively. The dynamic degree during 1990-2000 was -0.50%, while it was 2.43% during 2000-2015, which indicated that the activity degree of ecological land in 2000-2015 was much higher than that in 1990-2000. The decrease of grassland and the increase of forest land accelerated, while the reduction of wetland slowed down, and other ecological land change increased. All of these were mainly due to a series of key ecological projects that were carried out in Bashang plateau to control sandstorm source of Tianjin and Beijing, which have led to the rapid growth of forest; meanwhile, as the climate of Bashang plateau tended to be dry after entering 21 century, as well as the unreasonable utilization of grassland and wetland resources, the areas of grassland and wetland decreased. (3) The retention land rates of forest, grassland, wetland and other ecosystem land in the study area were 63.22%, 41.23%, 34.88% and 11.90% respectively, indicating that the spatial stability of forest was the best, followed by grassland and wetland, and the stability of other ecological land was the worst. The ecological evolution process was mainly concentrated in the transfer from grassland to non-ecological land and forest, the transfer from forest to grassland, the transfer from wetland to non-ecological land and the transfer from non-ecological land to grassland and forest. The transfer from non-ecological land to grassland and forest land showed that the series of ecological construction projects had achieved initial success. (4) The ecosystem service values of ecological land decreased from 46.01×108yuan in 1990 to 428.26×108yuan in 2015, enlarged by 831%. The average annual growth rate of ecosystem service values increased from 15.82% during 1990-2000 to 17.37% during 2000-2015. The forest ecosystem service values were the maximum, while the other ecological land ecosystem service values were the minimum. We should continue to strengthen the construction of ecological nature preserves, use biological recovery technology and artificial replenishment such as scientific grazing, adjust the industrial structure and use other measures to restore and increase the forest, wetland and grassland ecosystems. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Ecology
Controlled terms:Biology - Economics - Ecosystems - Forestry - Geographic information systems - Information systems - Land use - Storms - Wetlands
Uncontrolled terms:Average annual growth rates - Bashang plateau - Classification and evaluations - Ecosystem service values - GIS (geographic information system) - Pattern evolution - Quantitative structures - Service values
Classification code:403 Urban and Regional Planning and Development - 443.3 Precipitation - 454.3 Ecology and Ecosystems - 461.9 Biology - 903.3 Information Retrieval and Use - 971 Social Sciences
Numerical data indexing:Percentage -3.80e-01%, Percentage -5.00e-01%, Percentage -5.10e-01%, Percentage 1.19e+01%, Percentage 1.45e+00%, Percentage 1.58e+01%, Percentage 1.74e+01%, Percentage 2.43e+00%, Percentage 3.49e+01%, Percentage 4.12e+01%, Percentage 6.32e+01%, Percentage 7.30e-01%, Percentage 8.31e+02%
DOI:10.11975/j.issn.1002-6819.2017.02.039

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558505
Title:Characteristics of particle separation of erosion sediment in slop surface covered with sand
Authors:Tang, Shanshan (1); Gao, Haidong (1); Li, Zhanbin (1, 2); Ren, Zongping (1); Zhang, Hui (1); Su, Yuanyi (1); Zhi, Zaixing (1)
Author affiliation:(1) Key Laboratory of Northwest Water Resources and Environment Ecology of MOE, Xi'an University of Technology, Xi'an; 710048, China; (2) State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling; 712100, China
Corresponding author:Li, Zhanbin(zhanbinli@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:125-130
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Sediment size distribution greatly affects sediment transport and deposition. A better understanding of sediment sorting will improve the understanding of erosion and sedimentation processes, which in turn will improve erosion modeling. In this paper, using artificially simulated rainfall experiment, the sieved sand slope erosion and sediment grain size distribution and the change process were analyzed under the condition of 1.5 mm/min rainfall intensity, and the sieved sand slope erosion and sediment particle characteristics were explored, which aimed to further clarify the sieved sand slope erosion and sediment yield process. This paper studied the characteristics of sediment particles under different sand thickness, and there were 3 treatments, i.e. ST1 (sand thickness of 0.5 cm), ST2 (sand thickness of 1.0 cm), and ST3 (sand thickness of 1.5 cm). Malvern 2 000 laser particle size analyzer was used to measure the sediment particle composition, which was expressed by the mean weighted diameter (MWD). The results showed that most of coarse particulate matter was washed away within 0-10 min after the runoff production began; the sediment particle content of less than 0.054 mm was ST2<ST3<ST1 in 0-5 min after runoff, and that of greater than 0.054 mm was ST3<ST1<ST2; however, the sediment content less than 0.054 mm decreased with the increase of the thickness of sand-covered, the content of sediment particles larger than 0.054mm increased with the increase of the thickness of sand-covered after the 6th min of runoff; the erosion and sediment particles were mainly composed of silt; compared with bare slope, the E/U (effective particles/ultimate particles) value of clay in the erosion and sediment particles in 0-5 min was reduced by 36%, 64% and 58% respectively, and that of silt was reduced by 48%, 69%, 63% respectively when the thickness of sand was 0.5, 1.0, 1.5 cm respectively. For the sand covered slope, in the inter-rill erosion stage, runoff gave priority to transport the particles more than 0.054 mm, and sediment particles transported by runoff were mainly less than 0.054 mm in the rill erosion and combination of rill and interrill erosion stage; meanwhile, sand covering on slope affected the erosion sediment particle size and its existing form. The sediment particles that were eroded were mainly more than 0.054 mm at the early stage (0-10 min), and were mainly composed of the particles less than 0.054 mm after 10 min since the runoff began. The slope surface material was washed away mainly after 0-10 min since the runoff production started. Above all, after the slope was covered with sand, the clay existed in the form of aggregate, the silt existed in the form of single grain and the sand existed in the form of fine aggregate. This paper provides data support for further studying the effect of wind erosion on water erosion after sediment deposition. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Particles (particulate matter)
Controlled terms:Aggregates - Deposition - Erosion - Grain size and shape - Particle size - Particle size analysis - Rain - Runoff - Sand - Screening - Sediment transport - Sediments - Silt - Size distribution - Sorting
Uncontrolled terms:Coarse particulate matter - Erosion and sedimentation - Inter-rill erosions - Laser particle size analyzer - Particle separation - Sediment grain size - Sediment particle size - Sediment sorting
Classification code:406 Highway Engineering - 442.1 Flood Control - 443.3 Precipitation - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 802.3 Chemical Operations - 922.2 Mathematical Statistics - 951 Materials Science
Numerical data indexing:Percentage 3.60e+01%, Percentage 4.80e+01%, Percentage 5.80e+01%, Percentage 6.30e+01%, Percentage 6.40e+01%, Percentage 6.90e+01%, Size 1.00e-02m, Size 1.50e-02m, Size 5.00e-03m, Size 5.40e-05m, Time 0.00e+00s to 3.00e+02s, Time 0.00e+00s to 6.00e+02s, Time 6.00e+02s
DOI:10.11975/j.issn.1002-6819.2017.02.017

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558520
Title:Effect of different combinations of H-type cultivation frames on light and strawberry growth and yield
Authors:Wang, Chungling (1, 2); Song, Weitang (1, 3); Zhao, Shumei (1, 3); Qu, Mingshan (4)
Author affiliation:(1) College of Water Resources and Civil Engineering, China Agricultural University, Beijing; 100083, China; (2) College of Water Resources and Architectural Engineering, Tarim University, Alar; 843300, China; (3) Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, Beijing; 100083, China; (4) Beijing Soil and Fertilizer Working Station, Beijing; 100029, China
Corresponding author:Song, Weitang(songchali@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:234-239
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In the process of facility horticulture cultivation, the model of three-dimensional cultivation has been paid more and more attention. "H" type cultivation frame is widely used in stereo-cultivation of strawberry at present. In practical applications, growers choose the different layers of cultivation for planting. The most common arrangement of planting frame is two or three layers, which way can reduce the costs with higher yields and benefits, we do not know now. Therefore, an experiment aimed to select a better combination of cultivation frame was performed in this study. In this experiment, three combinations of "H" type cultivating shelves were set up, namely, two-layer frames arranged adjacently (T1), two-layer frame and three-layer frame are alternately arranged (T2), three-layer frames are arranged adjacently(T3), to compare the light conditions, growth status and yield differences. The experiment was carried out in a solar greenhouse in Changping district of Beijing from August 2015 to April 2016. The length of the greenhouse is 100 m and the span is 8 m. Strawberry varieties is "Hong Yan", planting date was August 29, 2015. Photosynthetic photon flux density (PPFD) of strawberry canopy and growth index were measured during the trial. Growth index include strawberry plant height and leaf chlorophyll relative content (SPAD), strawberry yield per plant, the number of fruits per plant, the average weight of fruit. Measured production time was three months. Results showed that under T1 treatment, the strawberries light conditions were the best of the upper and lower cultivars. During the experiment, the trend of light curves of the three cultivars in T2 and T3 were basically the same, but PPFD of the upper, middle and lower layers in T2 were higher than that in T3 corresponding position. During the experiment, the time length that light intensity at strawberry canopy reached light saturation point (LSP) of T2 upper layer was longer than that of T3 corresponding position; the time length of T2 middle layer reached the strawberry LSP was 240 min, and that of T3 middle layer was always below the LSP. In addition, the light intensity at strawberry canopy in the lower layer of T2 reached light compensation point was 230 min, and that of T3 lower layer was always below the light compensation point (LCP) all day. During the experiment, the time length that light intensity at strawberry canopy reached the LSP within two days of T1 and T2 were calculated, results showed that the time length reached LSP in T1 upper layer increased by 40% compared with that of T2. The time length of reaching at LSP in lower of T1 and T2 was 100 min and 0 min, respectively. The time length of reaching the LCP in the upper, lower layers of T1 increased by 9.3%, 21.4% compared with that of T2, respectively. Thus, the light environment of T1 was better than that of T2. Growth index of T1 strawberry was the best, yield per plant and the number of fruits per plant in T1 was higher than that of other treatments. Correlation indexes of strawberry yield were the worst in T3. During the test period, the yield per unit area of T1 was 50.8 kg, and the cost of T1 was the lowest in three treatments, yield per unit area of T1 was increased by 2.8%, 33.7% compared with that of T2 and T3, respectively. Therefore, strawberries of all two layers arrangement of "H" type cultivation frame got better lighting conditions, reduced costs and obtained better economic benefit. All two layers arrangement of "H" type cultivation frame (T1) was suitable for application in actual production. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:25
Main heading:Fruits
Controlled terms:Cost reduction - Costs - Cultivation - Forestry - Greenhouses - Light - Plants (botany)
Uncontrolled terms:Correlation index - Economic benefits - H cultivation frame - Light compensation point - Lighting conditions - Photosynthetic photon flux densities - Strawberry - Yield
Classification code:741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911 Cost and Value Engineering; Industrial Economics
Numerical data indexing:Mass 5.08e+01kg, Percentage 2.14e+01%, Percentage 2.80e+00%, Percentage 3.37e+01%, Percentage 4.00e+01%, Percentage 9.30e+00%, Size 1.00e+02m, Size 8.00e+00m, Time 0.00e+00s, Time 1.38e+04s, Time 1.44e+04s, Time 6.00e+03s
DOI:10.11975/j.issn.1002-6819.2017.02.032

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558489
Title:Yields and water-saving effects of crops as affected by variable rate irrigation management based on soil water spatial variation
Authors:Zhao, Weixia (1); Li, Jiusheng (1); Yang, Rumiao (1); Li, Yanfeng (1)
Author affiliation:(1) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100048, China
Corresponding author:Li, Jiusheng(lijs@iwhr.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:1-7
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Improving the uniformity of crop growth parameters and yield across the field is one of the objectives in utilizing the variable rate irrigation (VRI) technology. To improve the water management level of VRI, the crop growth parameters, including plant height, leaf area index (LAI), aboveground dry matter, leave relative chlorophyll content (SPAD), yield, and their spatial uniformity were compared between VRI and uniform rate irrigation (URI) managements, and the influences of soil available water holding capacity (AWC) on crop growth parameters and yield were also analyzed. This study was conducted at the experimental station of China Agricultural University in Zhuozhou, Hebei Province (39.45°N and 115.85°E) in 2014. This site belongs to the Taihang mountain alluvial flood plain and experiences a warm and semi-humid monsoon climate with an annual mean temperature of 11.6℃ and an annual mean precipitation of 563.3 mm. One quadrant of the center-pivot controlled area (1.64 hm2) was used in the experiment. The main soil types were loam and sandy loam, and both the coefficients of variation for sand and clay percentiles increased with depth in the site. During the growing seasons of winter wheat and summer maize, the seasonal rainfall for winter wheat (61.2 mm) was substantially lower than the long-term average, while it (311.6 mm) was ample for summer maize. According to the relationships between field capacity, wilting point, and clay, silt, and sand percentiles measured from the upper 0.6 m of the profile, the experimental area was delineated into 4 management zones with AWC varying from 152.2 mm to 161.4 mm for zone 1, from 161.4 mm to 170.9 mm for zone 2, from 170.9 mm to 185.1 mm for zone 3, and from 185.1 to 204.7 mm for zone 4. Each zone was then equally divided into 2 sub-zones to represent the VRI and URI treatments. Each VRI treatment was individually managed with an equal irrigation trigger point of 0.45AWC. For the URI treatments, irrigation was triggered when soil water content in the management zone having minimum AWC values (zone 1) depleted to 0.45AWC. The soil water content was measured with Trime access tubes and Decagon soil moisture sensors. A center-pivot irrigation machine that had been modified to enable to apply variable rate in different plots was used to implement the experiments. The results indicated that the soil water content was different among management zones with different AWC values, and the difference increased during the growing season of winter wheat as the less rainfall than that for summer maize. Correspondently, the total irrigation amount was same for winter wheat between URI and VRI treatments, while it was 14.1% lower for summer maize than that for the URI treatment since the frequent precipitation decreased the dependence on irrigation. Compared with URI management, there was minor effect of VRI management on spatial uniformity of winter wheat and summer maize; the variation coefficient values for all parameters of winter wheat increased from 0.02 to 0.04, while it decreased by 0.05 and 0.02 for aboveground dry matter and yield of summer maize, respectively. No significant influences of VRI management on crop growth parameters and yield were detected, while their differences were significant among the management zones. The experimental results suggested that the management zones with different AWC should be managed individually with different irrigation trigger points to improve the uniformity of crop growth and to maximize the crop yield. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Crops
Controlled terms:Agricultural machinery - Agriculture - Irrigation - Moisture control - Plants (botany) - Rain - Soil moisture - Soils - Water conservation - Water content - Water distribution systems - Water management - Water resources
Uncontrolled terms:Management zones - Soil available waters - Summer maize - Uniformity - Winter wheat
Classification code:443.3 Precipitation - 444 Water Resources - 446.1 Water Supply Systems - 483.1 Soils and Soil Mechanics - 731.3 Specific Variables Control - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 1.41e+01%, Size 1.52e-01m to 1.61e-01m, Size 1.61e-01m to 1.71e-01m, Size 1.71e-01m to 1.85e-01m, Size 1.85e-01m to 2.05e-01m, Size 3.12e-01m, Size 5.63e-01m, Size 6.00e-01m, Size 6.12e-02m
DOI:10.11975/j.issn.1002-6819.2017.02.001

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558500
Title:Monitoring cotton root growth dynamics under mulched drip irrigation using monirhizotron technique
Authors:Chen, Wenling (1, 2); Jin, Menggui (1, 2); Liu, Yanfeng (2); Xian, Yang (1, 2); Huang, Jinou (2, 3)
Author affiliation:(1) Laboratory of Basin Hydrology and Wetland Eco-restoration, China University of Geosciences, Wuhan; 430074, China; (2) School of Environment Studies, China University of Geosciences, Wuhan; 430074, China; (3) Zhejiang Institute of Geo-environment Monitoring, Hangzhou; 310007, China
Corresponding author:Jin, Menggui(mgjin@cug.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:87-93
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Fine roots are the most important and active part of the root system. Due to the inaccessibility of root systems, special techniques are required to investigate the fine root distribution and root growth parameters. Conventional method to study the root system such as the quadrate monolith method always consume large labors, cause destruction to the root system, can't monitor the root growth in suit and will cause the error of the measurement. While minirhizotron technique provides a nondestructive, in situ method for viewing roots growth images and is one of the best tools available for directly studying root system. In order to meticulously investigate the growth dynamic of cotton fine root under film mulch drip irrigation, a field experiment was conducted in 2014 by using minirhizotron technique to measure the growth of cotton root in situ at the Bazhou Experimental Station in Korla, Xinjiang, China. Reference standard used in this experiment was quadrate monolith method. The minirhizotron and quadrate monolith methods were applied to analysis the growth of cotton root under mulched drip irrigation with fresh water, and the root growth parameters of the two methods were analyzed to establish a regression model. Results showed that, the cotton new root and dying root could be judged by the colour of root from the root images, and the variation parameters of length and diameter of cotton new root and dying root can also be directly estimated from the cotton root growth images collected from one of the minirhizotron tubes at the depth of 10-20 cm. The cotton new root growth turn over at the depth of 10-20 cm was 1.844 mm/d with minirhizntron method, more and more root turned to be dying root as time gone on in the periods of blooming stage to boll opening stage. The parameters of mean diameter, total projection area and total surface area of cotton new root increased with time increasing, while those parameters of dying root decreased with time increasing. The deepest growth of cotton root in soil was observed at 50 cm through the two methods. The total root length density determined by using minirhizotron technique in the blooming stage (08-07), boll stage (08-17 and 08-27), and boll opening stage (09-06) were 5.49, 5.90, 5.59 and 4.49 cm/cm2respectively. The total root length density determined by quadrate monolith method in the blooming stage (07-16), boll stage (08-17) and boll opening stage (09-06) were 3.29, 5.14 and 5.78 cm/cm3respectively. The distributions of cotton root length density at different depth of soil were the same observed through the two methods, root length density was increased with the increase of soil depth between 0-30 cm, the maximum root length density was observed at the depth of 20-30 cm, root length density was decreased with the increase of soil depth between 30-50 cm. The results of the root length density among two methods were significant correlation at 0.99 confidence level. The equation of linear regression could be used to estimate the actual root length growth parameter after we acquired the root length growth parameter with minirhizotron method. It further showed that the minirhizotron technique could provid as a reliable, nondestructive and in suit method for directly viewing and studied the growth of cotton fine root change within soil under mulched drip irrigation, and by using the root processing software (WinRHIZOTron MF 2012) we could easily acquire the root parameters after collected the root growth images. For better understanding the meticulous growth dynamic of cotton fine root, steps must be taken to insure good soil/minirhizotron tubes contact without disturbing the soil; increasing the monitoring scope and the frequency of cotton root growth images collection through different periods of cotton growth will be needed in further research. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Film growth
Controlled terms:Cotton - Forestry - Growth (materials) - Irrigation - Monitoring - Plants (botany) - Regression analysis - Soils - Superconducting films
Uncontrolled terms:Fine roots - Monirhizotron - Quadrate monolith method - Root growth - Root length density
Classification code:483.1 Soils and Soil Mechanics - 708.3 Superconducting Materials - 821.3 Agricultural Methods - 821.4 Agricultural Products - 922.2 Mathematical Statistics - 951 Materials Science
Numerical data indexing:Size 0.00e+00m to 3.00e-01m, Size 1.00e-01m to 2.00e-01m, Size 2.00e-01m to 3.00e-01m, Size 3.00e-01m to 5.00e-01m, Size 5.00e-01m
DOI:10.11975/j.issn.1002-6819.2017.02.012

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558530
Title:Fluorescence detection of chitosan oligosaccharides plant immune elicitors based on droplets-microfluidics
Authors:Cang, Xiaoxin (1, 2); Zhao, Xiaoming (2); Zhong, Runtao (3); Wang, Wenxia (2); Yin, Heng (2); Zhu, Jingbo (1); Ding, Yan (1)
Author affiliation:(1) School of Food Science and Technology, Dalian Polytechnic University, Dalian; 116034, China; (2) Dalian Institute of Chemical Physics, Chinese Academic of Sciences, Dalian; 116023, China; (3) School of Environmental Science and Engineering, Dalian Maritime University, Dalian; 116026, China
Corresponding author:Ding, Yan(dingyan_515@hotmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:302-307
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The plant immune elicitors can induce a line of defense responses in plants and are identifed as new type of biological pesticides. At present stage, new plant immune elicitor is screening with potted plants or field experiments, which is time-consuming and high-cost. The droplet microfluidic technology, which is originated from analytical chemistry and owns micro-channel network structure, has properties of high throughput, high sensitivity, low consumption of reagent, no cross contamination and rapid reaction. These advantages provide a novel platform for screening plant immune elicitors. Chitosan oligosaccharides (COS) are obtained by degradation of chitosan. It was reported that COS could activate plant innate immunity, such as: stimulate H<inf>2</inf>O<inf>2</inf>(hydrogen peroxide) production, induce defense response by NO (nitric oxide) pathway, make a synthesis of phytoalexin, impact the jasmonic acid/ethylene (JA/ET) signaling marker, trigger defense-related gene expression, cause changes in protein phosphorylation, activate mitogen-activated protein kinases (MAPKs), and possess antimicrobial activity against bacteria and fungi in plant. Because of the advantages and the high solubility, nontoxicity, and biocompatibility, COS are considered as an effective plant immune elicitor by researchers. To preliminarily applying droplet microfluidic technology in plant immune elicitor screening, integrated microfluidic chip with droplets formation structure was designed and fabricated. COS were chosen as positive reagent, and BY-2 tobacco cells played as model plant cell. The flow rate of mobile phase was measured and established for BY-2 tobacco cells droplets formation, and the single cell encapsulating efficiency was calculated. Then COS and NO probe were dumped into the droplets with BY-2 tobacco cells, and the fluorescence intensity of NO probe from droplets was detected to evaluate the feasibility of screening the plant immune elicitor COS. To make the comparative analysis, the fluorescence intensity was compared with the same reaction system in 96-well plate. The results showed that at the flow rates of 100 μL/h in cell suspension and 300 μL/h in oil, the sizes of generated droplets were suitable to encapsulate the cells. The BY-2 cell clusters could be dispersed in isotonic solution, and every droplet encapsulated single cell. The ratio of droplets encapsulating single cell was about 22.9%. The ratio conformed to Poisson distribution. The fluorescence intensity of droplets incubated with COS was detected by fluorescence microscope. The fluorescence intensity from the COS/NO probe/BY-2 cell group was significantly higher than the control groups. In the comparative analysis experiments, the fluorescence intensity of droplets showed similar trend compared with the same reaction system in 96-well plate. This result implied that the cell treated with COS in droplets showed similar trend in defense responses compared to traditional screening method with 96-well plate. Thus, the droplets with COS/NO probe/BY-2 cell show high fluorescence intensity that can be detected by fluorescence microscope, which implies that integrated with fluorescence detecting technique, droplets microfluidics and fluorescence probe can be a novel platform for screening plant immune elicitors. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Drops
Controlled terms:Biocompatibility - Biosynthesis - Cell culture - Chemical analysis - Chemical reactions - Chitin - Chitosan - Contamination - Encapsulation - Fluorescence - Gene expression - Microfluidics - Network security - Nitric oxide - Oligosaccharides - Plates (structural components) - Poisson distribution - Probes - Proteins - Suspensions (fluids) - Tobacco
Uncontrolled terms:Anti-microbial activity - Chitosan oligosaccharide - Fluorescence intensities - Integrated microfluidic chips - Mitogen activated protein kinase - Plant immune elicitors - Protein phosphorylation - Tobacco cells
Classification code:408.2 Structural Members and Shapes - 461.9 Biology - 461.9.1 Immunology - 632.5.1 Microfluidics - 723 Computer Software, Data Handling and Applications - 741.1 Light/Optics - 802.2 Chemical Reactions - 804 Chemical Products Generally - 821.4 Agricultural Products - 922.1 Probability Theory
Numerical data indexing:Percentage 2.29e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.042

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558512
Title:Soybean growth assessment method based on NDVI and phenological calibration
Authors:Han, Yanxin (1); Meng, Jihua (1); Xu, Jin (1)
Author affiliation:(1) Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing; 100101, China
Corresponding author:Meng, Jihua(mengjh@radi.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:177-182
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The timely and accurate crop condition monitoring can provide government policy makers and farmers with information of crop growth, so that they can take promptly field management measures to achieve scientific management and crop yield-increasing. With the development of remote sensing technology, crop condition monitoring by remote sensing has become a research hotspot. Former studies have shown that normalized difference vegetation index (NDVI) is highly correlated with leaf area index (LAI) and leaf chlorophyll content, and can be used to indicate the growth condition of crops. However, it is hard to eliminate the influence of objective factors on crop condition monitoring due to the lack of evaluation criteria. Beside the crop growth condition difference itself, the phenophase difference between fields also has a great influence on crop condition monitoring. To address the problems above, a method of assessing soybean condition by using the historical NDVI time series was designed. In this study, the research target is soybean in Hongxing Farm, which is located in Heilongjiang province. Based on the available multi-spectral HJ-1 CCD data, the historical NDVI dataset from the year 2010 to 2014 was collected. The NDVI variation trend in soybean growth season was analyzed and an inter-annual comparison during soybean growth period was implemented which was integrated with ground data. The high-quality images can't be acquired at day frequency due to the temporal resolution and the cloud influence. A linear interpolation was thus applied to the original data to obtain everyday NDVI dataset. Then a profile, which reflected the soybean growth process was built according to the reconstructed NDVI data from 2010 to 2014. The profile can provide four threshold values every day to categorize soybean condition into five grades which is worst, poor, fair, good and excellent respectively. On the basis of that, the criterion of soybean condition classification was established to assess the growth condition of soybean accurately. A preliminary soybean growth condition map can be produced according to the criterion. Then the critical phenological stages of soybean was extracted based on NDVI time series to reduce the phenophase impact on crop condition monitoring. First, an everyday NDVI dataset at pixel scale in the year 2014 was built using linear interpolation. A simple procedure based on Savitzky-Golay filter and Gaussian function was then implemented to remove the noise in the contaminated NDVI data and fit the growth curve. The result of soybean growth condition monitoring can be calibrated on the basis of the correlation of NDVI and the podding date which can be estimated by analyzing the characteristics of the curve. The yield investigation at field scale was carried out to validate the accuracy of the soybean growth condition assessment method. The results showed that the consistency between soybean condition level and yield level reached 58.5% and increased to 75.6% with the phenological calibration. The pre- and post-calibration consistency were 87.8% and 95.1% respectively when the tolerance was defined as one grade. The proposed method which based on the historical NDVI dataset and the result of key phenophase mapping indicates the ability of reducing the impact of objective factors and phenophase when assessing soybean growth condition. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Condition monitoring
Controlled terms:Agriculture - Calibration - Crops - Forestry - Interpolation - Monitoring - Plants (botany) - Remote sensing - Time series analysis
Uncontrolled terms:Crop condition - Leaf chlorophyll content - NDVI - Normalized difference vegetation index - Phenophase - Remote sensing technology - Savitzky-Golay filter - Soybean
Classification code:821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 921.6 Numerical Methods - 922.2 Mathematical Statistics
Numerical data indexing:Percentage 5.85e+01%, Percentage 7.56e+01%, Percentage 8.78e+01%, Percentage 9.51e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.024

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558491
Title:Influence of sugarcane harvester cutterhead axial vibration on sugarcane ratoon cutting quality
Authors:Zhou, Jinghui (1, 3); Li, Shangping (2, 4); Yang, Daiyun (4); Zhong, Jiaqin (5); Mo, Hanning (1); Zhang, Biao (4); Deng, Xiong (4)
Author affiliation:(1) College of Light Industry, Guangxi University, Nanning; 530004, China; (2) College of Information Science and Engineering, Guangxi University for Nationalities, Nanning; 530006, China; (3) Guilin University of Technology at Nanning, Nanning; 530001, China; (4) College of Mechanical Engineering, Guangxi University, Nanning; 530004, China; (5) College of Mechanical and Marine Engineering, Qinzhou University, Qinzhou; 535099, China
Corresponding author:Li, Shangping(spli501@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:16-24
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In view of the problems of the low cutting quality of sugarcane ratoon, literatures at home and abroad mostly focus on the study of machine structures and movement parameters of harvester, neglecting possible influence of cutterhead's vibration on sugarcane cutting. Research team discovered in the earlier research stage that there were certain connections between cutterhead vibration of sugarcane harvester and ratoon cutting quality. Based on early theoretical analysis, research team gave further studies on their relationship by controlling the axial vibration of cutterhead triggered by different weights of sugarcanes on cutterhead. To realize controllable axial amplitudes of cutterhead, we analyzed the mechanism of axial vibration generated by rotor dynamics. It was concluded that during the cutting movement an eccentric mass on the cutterhead produced axial vibration: owing to the existence of eccentricity, dynamic deflection was created under the action of centrifugal force when the cutterhead was rotating, and then the axial harmonic force which related to the eccentric distance was produced, forcing the cutterhead to generate axial vibrations. This suggestion was verified by a series of single factor experiments. An unbalanced mass, the position and mass of which could be varied, was installed on the cutterhead of the self-developed laboratory platform to achieve controllable axial vibrations and measurable vibrations produced when sugarcane roots were cut and transferred on the simulating cutterhead. In this series of single factor experiments, the amplitudes at a fixed point on the edge of cutterhead on axial direction were measured by the laser displacement sensor in terms of changing unbalanced mass. The experiments also realized controllable axial vibrations of cutterhead. Based on the above results, under the controllable axial vibration conditions, a series of single-factor and orthogonal experiments of sugarcane ratoon cutting were carried out. Taking the length and width of sugarcane ratoon crack and the number of experimental ratoons as experiment indices, we completed the comprehensive evaluation on sugarcane ratoon cutting quality with the improved entropy method, and further carried out the variance analysis, correlation analysis and regression analysis. Experiment results showed that: 1) The cutter's axial vibrations could be controlled by various weights and positions of unbalanced mass. The controllable range was 0.91-2.59 mm under the experiment conditions and there is a strong positive correlation between unbalanced mass and cutterhead amplitude.2) With the statistics, the linear regression equation of sugarcane ratoon cutting quality and cutterhead axial vibration was made. It was found that there was a strong positive correlation between the axial amplitude of cutterhead and the sugarcane ratoon cutting quality, and the correlation coefficient was 0.87. The regression equation suggested the sugarcane cutting quality was sensitive to the changes of cutterhead axial amplitude. 3) Under the orthogonal test condition, unbalanced mass had the significant influence on ratoon cutting quality and axial vibration of cutterhead at the significant level of 0.05; and it was suggested that among the 3 factors i.e. cutterhead unbalanced mass, cutterhead rotation speed and sugarcane conveying speed, the first one had the most significant effect on cutting quality, the sugarcane conveying speed ranked the second, and the cutterhead rotation speed had the least influence. Due to the strong positive correlation between cutterhead unbalanced mass and cutterhead amplitude, the significant influence on cutting quality brought by cutterhead axial amplitude could be confirmed. This paper preliminarily reveals the impact rule of cutterhead axial vibration on sugarcane ratoon cutting quality, and provides the reference for further studying the breaking mechanism of root caused by cutterhead vibration during the cutting, exploring the sugarcane harvester's design method based on dynamic characteristics, and developing the sugarcane harvester suitable for hilly area. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Vibration analysis
Controlled terms:Crops - Dynamics - Harvesters - Machinery - Mechanization - Quality control - Regression analysis - Rotation
Uncontrolled terms:Axial vibrations - Cutterhead - Cutting quality - Unbalance mass - Vibrations
Classification code:601 Mechanical Design - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 913.3 Quality Assurance and Control - 922.2 Mathematical Statistics - 931.1 Mechanics
Numerical data indexing:Size 9.10e-04m to 2.59e-03m
DOI:10.11975/j.issn.1002-6819.2017.02.003

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558529
Title:Discrimination of wine age of Chinese rice wine by electronic tongue based on amino acid profiles
Authors:Yu, Haiyan (1); Zhang, Yan (1); Xu, Chunhua (1); Tian, Huaixiang (1)
Author affiliation:(1) Department of Food Science and Technology, Shanghai Institute of Technology, Shanghai; 201418, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:297-301
Language:English
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To ensure a good reputation for the producers and to guarantee the basic quality of wine for the consumers, an electronic tongue (E-tongue) coupled with a chemometric method was applied to rapidly discriminate the wine age of Chinese rice wine. Amino acid profiles analyzed by an amino acid analyzer together with principal component analysis (PCA) was used for validation of the wine age of the Chinese rice wine samples sourced from 1-year, 3-year, and 5-year. E-tongue responses collected by a potentiometric E-tongue together with discriminant analysis (DA) were used for the rapid discrimination of the wine age. The correlation between the E-tongue responses and the amino acid profiles was established by partial least squares regression (PLSR). The results showed that the calibration and validation samples were all correctly discriminated by the E-tongue coupled with DA. The E-tongue could be used for screening isoleucine (Ile), aspartic acid (Asp), tyrosine (Tyr), and valine (Val), with a residual predictive deviation (RPD) of greater than 2.0. The results indicated that using an E-tongue combined with DA was a reliable method for the discrimination of the wine age of Chinese rice wines. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Electronic tongues
Controlled terms:Amino acids - Chromatography - Discriminant analysis - Least squares approximations - Models - Principal component analysis - Wine
Uncontrolled terms:Aspartic acids - Calibration and validations - Chemometric method - Chinese rice wine - Partial least squares regressions (PLSR) - Potentiometric - Reliable methods - Wine ages
Classification code:801 Chemistry - 804.1 Organic Compounds - 822.3 Food Products - 921.6 Numerical Methods - 922 Statistical Methods - 922.2 Mathematical Statistics
Numerical data indexing:Age 1.00e+00yr, Age 3.00e+00yr, Age 5.00e+00yr
DOI:10.11975/j.issn.1002-6819.2017.02.041

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558518
Title:Trajectory tracking for group housed pigs based on locations of head/tail
Authors:Gao, Yun (1, 2); Yu, Hou'an (1); Lei, Minggang (2, 3); Li, Xuan (1, 2); Guo, Xu (1); Diao, Yaping (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan; 430070, China; (2) The Cooperative Innovation Center for Sustainable Pig Production, Wuhan; 430070, China; (3) College of Animal Science and Technology, College of Animal Medicine, Huazhong Agricultural University, Wuhan; 430070, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:220-226
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Observing animal's individual and social behaviors is the most effective way to assess animal welfare and healthy. Automated trajectory tracking based on head/tail locations is supposed to be extremely helpful for the realization of pig behavior recognition, especially for group housed pigs in the commercial pig facility. The methods of trajectory tracking for group housed pigs based on head/tail location were described in this paper. The video of group housed nurseries was taken in a commercial pig breeding farm of Hubei Jinlin Original Breeding Swine Co. Ltd. on January 12th, 2016. A high resolution camera (Woshida CL03) was used to record 15 min video. Afterwards, image frames were extracted from the original video in a one-second time interval. Image frames were processed in a computer (configured with IntelCore i7-4790 CPU (central processing unit), 3.6 GHz, 8 G memory) with MATLAB software platform. The image processing for each image frame included 4 steps: background removal, pigs division, head/tail identification and trajectory tracking modification. The background removal was based on the RGB (red, green, blue) color space, from which a vector of RGB mean values of the pig's body was calculated. If the Euclidean distance between the RGB values of one pixel and the RGB mean values vector was less than a small threshold of 100, the pixel was involved in a pig body area and set as 1. Otherwise, it was outside any pig body area and set as 0. When all pixels of the image frame were scanned and calculated by this method, a binary image was acquired. The white area referred to pig's body area, while the black area referred to the background. After that, the morphology erosion and expansion were utilized before the watershed segmentation algorithm to improve the dividing effect for the pigs with adhesion. Pigs division was implemented on the binary images with the improved watershed segmentation algorithm. To discriminate each pig in each image frame, a video tracking and marking method was necessary to be implemented in the video. After being manually marked with the identify number in the first frame, each pig had a unique number and was labelled automatically throughout the video. Abstracting image frames from the video with a very short time interval (1 s), the distance of 2 centroids of the identical pig between 2 continuous image frames would be sufficiently small. Therefore, the video tracking was to find the pig with the closest distance in the next image frame and mark it with the same identify number of the current pig until all the pigs were marked. After each pig was marked throughout the video, using the head/tail location as the coordinates of the pig, the trajectory of each pig in herd could be tracked by the trajectory calculation. Extracting the outline of each pig in frames, the head and the tail outlines were divided from the whole outline, after a sixth of whole outline distance was moved along the outline in 2 opposite directions from the 2 intersection points of the outline and short axis of the minimum bounding rectangle. After the head/tail outline curve was gained from each pig outline, 2 recognition algorithms, the analogous Hough clustering recognition algorithm and the roundness recognition algorithm, were employed to identify the head/tail of each pig. Thus the location of the pig's head/tail could be spotted by locating the centroid of the heat/tail curve. Then the trajectory tracking of the pigs was calculated based on the location of head/tail, and corrected by the motion trends of pigs. Experiment showed that the background was successfully removed from each image frame using the Euclidean distance of RGB values between the pixels and the mean value vector. The improved watershed segmentation algorithm has been verified as an effective tool to divide the pigs with adhesion. The identify number of each pig was tracked from the first frame to the end. The average recognition rate of analogous Hough clustering algorithm was 71.79% for the identification of pig's heads/tails, while the roundness algorithm was 79.67%, which was less sensitive to the distortion of head outline curve. If not including the pigs outside the camera range, the recognition rates would be up to 75% and 85.7% respectively. The roundness algorithm shows an obvious advantage in comparison. The modified trajectory of each pig shows a high agreement with the manually labelled trajectory. More understanding for pigs' behaviors can be acquired from the trajectory of head/tail locations. This trajectory tracking method provides a good reference for further research of behavior recognition. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:32
Main heading:Image segmentation
Controlled terms:Adhesion - Algorithms - Animals - Behavioral research - Binary images - Bins - Cameras - Clustering algorithms - Heating - Image processing - Image recognition - Location - Mammals - MATLAB - Pixels - Program processors - Trajectories - Vector spaces - Video recording
Uncontrolled terms:Individual pig - Minimum bounding rectangle - Pig herd - Trajectory calculations - Trajectory tracking - Trajectory tracking method - Watershed segmentation - Watershed segmentation algorithm
Classification code:694.4 Storage - 716.4 Television Systems and Equipment - 723.2 Data Processing and Image Processing - 742.2 Photographic Equipment - 903.1 Information Sources and Analysis - 921 Mathematics - 951 Materials Science - 971 Social Sciences
Numerical data indexing:Frequency 3.60e+09Hz, Percentage 7.18e+01%, Percentage 7.50e+01%, Percentage 7.97e+01%, Percentage 8.57e+01%, Time 1.00e+00s, Time 9.00e+02s
DOI:10.11975/j.issn.1002-6819.2017.02.030

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558490
Title:Design and parameter optimization on teeth residue plastic film collector of ridged peanut
Authors:Shi, Lili (1); Hu, Zhichao (1); Gu, Fengwei (1); Wu, Feng (1); Wu, Penglai (1)
Author affiliation:(1) Nanjing Institute of Agricultural Mechanization Ministry of Agriculture, Nanjing; 210014, China
Corresponding author:Hu, Zhichao(nfzhongzi@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:8-15
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the increasing use of agricultural plastic film, the pollution it bringing is becoming more and more serious. It has become a problem which needs to be solved urgently. In China, the plant areas of peanut were expanded to 460.6 hm2in 2014, which accounted for about 17.9% of the global area of peanut crops. And its output reached to 16.481 7 million tons in the same year, which accounted for about 38.9% of the global production of peanut yields. Therefore, design and experiment on plastic film collector of ridged peanut means a great deal to us. The collecting film teeth residue plastic film collector of ridged peanut was designed, and the whole structure and working mechanism of the machine were introduced. Therefore, the main operation components of it were designed and the structure parameters were determined at last. To solve the problem of residual film recycling after peanuts harvest, we designed the plastic film residue collector, and then optimized its parameters. The key structural parameters were determined by mechanism analysis and tests. The collecting film teeth diameter of the first row, the second row, and the third row were set as 10, 8 and 8 mm, respectively. The harrowing tooth was made of No.65 manganese steel, and the harrowing tooth's lug angle ranges from 10° to 35°. The collecting film teeth space on the first row, the second row, and the third row were 120, 100 and 80 mm, respectively. The four-dimensional slice of MATLAB and response surface analysis was done on the machine speed, the harrowing tooth's lug depth and its radius of curvature. The quadratic regression model between film removing ratio and machine operating speed, the embedded depth of the rake, tooth curvature radius was built. The optimal structure parameters of plastic film residue collector were obtained by response surface analysis. The response surface analysis of the model was optimized, and the effect of 3 factors on the recovery of the residual membrane was significant. The order of strength is: machine operating speed> embedded depth of the collecting film teeth > collecting film teeth curvature radius. The machine was optimized by parameter optimization. The machine operating speed, depth of collecting film teeth, tooth's radius of curvature of machine was 1.2 m/s, 11mm, and 222 mm, respectively. And film recycling rate was about 93% through the field test. Its relative error was 2% compared with the predictive value. In conclusion, the optimization scheme was feasible. This paper could provide theoretical basis for optimization of related machines. With the preliminary experiment, the collecting film teeth residue plastic film collector of ridged peanut has good film quality, which meets the design requirements of plastic recycling machine. Removing mechanism on the collecting film teeth residue plastic film collector of ridged peanut is the further research. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Plastic recycling
Controlled terms:Agricultural machinery - Agriculture - Oilseeds - Optimization - Plastic films - Recycling - Regression analysis - Shape optimization - Structural design - Structural optimization - Surface analysis - Surface properties
Uncontrolled terms:Agricultural plastic films - Parameter optimization - Plastic film residues - Quadratic regression - Response surface analysis - Response surface method - Structural parameter - Structure parameter
Classification code:408.1 Structural Design, General - 452.3 Industrial Wastes - 817.1 Polymer Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.5 Optimization Techniques - 922.2 Mathematical Statistics - 951 Materials Science
Numerical data indexing:Percentage 1.79e+01%, Percentage 2.00e+00%, Percentage 3.89e+01%, Percentage 9.30e+01%, Size 1.00e-01m, Size 1.10e-02m, Size 2.22e-01m, Size 8.00e-02m, Size 8.00e-03m, Velocity 1.20e+00m/s
DOI:10.11975/j.issn.1002-6819.2017.02.002

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558523
Title:Solid phase distribution simulation of culture pond with recirculating biofloc technology based on computational fluid dynamics
Authors:Shi, Mingming (1); Ruan, Yunjie (1, 2); Liu, Huang (3); Guo, Xishan (1); Ye, Zhangying (1); Han, Zhiying (1); Zhu, Songming (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou; 310058, China; (2) Department of Biological and Environmental Engineering, Cornell University, Ithaca; 14850, United States; (3) Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai; 200092, China
Corresponding author:Ruan, Yunjie(ruanyj@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:252-258
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biofloc technology (BFT) has been widely used in situ tilapia rearing for its benefits such as saving protein-feed and reducing the adverse impacts on environment. And biofloc concentration has huge effect on aquaculture system. More specifically, TSS(total suspend solid) and the uniformity of the biofloc distribution can greatly affect cultured animals on feeding enthusiasm, and high TSS even will threat the survival of breeding objects. In production, because of the biofloc sedimentation, the bottom of traditional BFT system usually extremely high, so the recirculating biofloc technology (RBFT) system has become a hot topic in recent study. To investigate the improvement on biofloc distribution uniformity of RBFT system compared with situ BFT system, an Euler-Euler multi-phase turbulence 3-D model combined with the kinetic theory of granular flow was applied to simulate the solid-liquid-gas three-phase flow in culture ponds of two kinds of BFT system. At first, the tank meshing was finished based on the commercial software Workbenching 15.0. The grid independent validation was done to choose the acceptable mesh. At last, the mesh was imported in numerical simulation software (Fluent) to analyze the velocity contours and streamlines of liquid phase, distribution characters of solid phase in these two models. In this simulation, pressure-based solver and second-order implicit transient formulation were adopted. The boundary conditions of water and air inlet were set as velocity, and their outlet were regard as pressure outlet equated to the local atmospheric pressure. What's more, according to the SIM-PLE algorithm, pressure-velocity coupling was calculated. The bioflocs were regarded as to be distributed in the bottom initially. Unsteady simulations were performed when all residuals fall below 10-3, while 40 iterations per time step were used to ensure numerical stability. To have an accurate results, third-order monotone upstream-centered schemes for conservation laws (MUSCL) was used. The simulation results show that when the hydraulic retention time (HRT) of RBFT system is 0.45 h, its flow field has an irregularly varying flow directions namely spreading all over the space, and a severe turbulent flow is complex in contrast with BFT system. On one hand, this flow field results in a more homogeneous velocity distribution and less dead zone flow field in recirculating culture pond, and on the other hand, bioflocs are gathering at the main center area, which is beneficial to biofloc recirculating. What is particularly worth mentioning is that there is only a small amount of biofloc's sedimentation at bottom in recirculating culture pond, and this result can efficiently avoid the anaerobic bacterium's breeding caused by the biofloc sedimentation at bottom corners of culture ponds. In addition, the solid phase volume fraction is about 0.1 in recirculating culture pond's model, and this concentration of suspended solid is suitable for growth of cultured aquatic animal like tilapia and shrimp. According to the comparison between simulation value and experimental data, the simulating value's error is less than 20%, and the simulation results are trustworthy. In conclusion, the study shows that the RBFT system can overcome the disadvantages including uneven distribution of biofloc and too much dead zone in situ BFT system. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Aquaculture
Controlled terms:Air - Animals - Atmospheric pressure - Bacteria - Computation theory - Computational fluid dynamics - Computer software - Flow fields - Fluid dynamics - Incompressible flow - Lakes - Liquefied gases - Mesh generation - Sedimentation - Velocity - Velocity distribution
Uncontrolled terms:Distribution uniformity - Homogeneous velocity distributions - Hydraulic retention time - Kinetic theory of granular flow - Multiphase fluids - Numerical simulation software - Pressure-velocity coupling - Technology system
Classification code:443.1 Atmospheric Properties - 631.1 Fluid Flow, General - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 802.3 Chemical Operations - 804 Chemical Products Generally - 821.3 Agricultural Methods - 922.2 Mathematical Statistics - 931.1 Mechanics
Numerical data indexing:Percentage 2.00e+01%, Time 1.62e+03s
DOI:10.11975/j.issn.1002-6819.2017.02.035

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558509
Title:Analysis on N application rates considering yield and N<inf>2</inf>O emission in potato production
Authors:Zhou, Long (1); Long, Guangqiang (1); Tang, Li (1); Zheng, Yi (1)
Author affiliation:(1) College of Resources and Environmental Sciences, Yunnan Agriculture University, Kunming; 650201, China
Corresponding author:Tang, Li(ltang@ynau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:155-161
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agriculture soil is the important source of N<inf>2</inf>O emission. Fertilization can increase crop yield, but also can enhance emissions of greenhouse gas N<inf>2</inf>O. There is an important guiding significance to analyze the relationship between yield, soil N<inf>2</inf>O emissions under varied nitrogen levels for ensuring crop yield and reducing environment impacts. The potato is the fourth largest planting crops in the world, and China is the biggest producer. Effect of N application rates on soil N<inf>2</inf>O emission and crop yield have been intensively studied in the temperate zone with continental climate, and these studies simply focused on either yield or N<inf>2</inf>O emission, while it has never been reported in the north subtropical monsoon climate. In this study, field experiment was conducted in the Daheqiao experiment base (23°32'N, 103°13'E) of Yunnan agricultural university, in Xundian County, Yunnan province of China, from April to November in 2015. And four N application levels (unfertilized-N0, 0; low nitrogen application rate -N1, 67.5 kg/hm2; conventional nitrogen application rate-N2, 125 kg/hm2; high nitrogen application rate -N3, 187.5 kg/hm2) with three replications were compared based on potato cultivation of Huize 2. Aiming to study the effect of N application rates on potato yield and soil N<inf>2</inf>O emission at growing period, soil N<inf>2</inf>O emission was collected in situ by static chamber and analyzed using gas chronographs technique. Simultaneously, optimizing N application rates to increase yield and minimize N<inf>2</inf>O emission was analyzed. The results showed that fertilization increased the potato yield and cumulative N<inf>2</inf>O emission significantly. The soil was a source of atmospheric N2O emissions in whole potato growing season, and an obvious seasonal difference was monitored. Compared with N0, N1, N2, and N3 treatments increased by78.5%, 93.1% and 95.6% in yield. The cumulative N<inf>2</inf>O emission of N1, N2, and N3 treatments were 2.3, 4.4, and 6.7 times that of N0 treatment, respectively. The potato yield was largest when N application rates 125 kg/hm2, and no longer increased with the increasing N application rate. The first and secondary peaks of N<inf>2</inf>O emission were observed at the flourishing stage (23 May) and harvest stage (11 August), respectively. Meanwhile, N<inf>2</inf>O emission factor and yield-scaled N<inf>2</inf>O intensity significantly improved with the increase of N fertilizer. The proportion of the loss of nitrogen in the form of N<inf>2</inf>O significantly increased with the increasing N fertilizer. Nitrate intensity could effectively reflect the intensity of soil N<inf>2</inf>O emission. N<inf>2</inf>O emission flux was significantly correlated with soil temperature and humidity only at low N levels (N0, N1).Soil NO<inf>3</inf>--N content was the key factor for N<inf>2</inf>O emission at high N levels. Comprehensive considering the average N<inf>2</inf>O emission coefficient (1%) reported by IPCC as the fertilization standard of nitrogen and potato yield in farmland ecosystem,therefore, the reasonable N application rates were about 62.5 kg/hm2in potato production. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:40
Main heading:Nitrogen
Controlled terms:Agriculture - Atmospheric humidity - Crops - Cultivation - Ecosystems - Emission control - Fertilizers - Gas emissions - Greenhouse gases - Nitrogen fertilizers - Soils
Uncontrolled terms:Emission coefficient - Guiding significances - Nitrogen application rates - Potato - Reducing environment - Seasonal differences - Subtropical monsoon climate - Yield
Classification code:443.1 Atmospheric Properties - 451.1 Air Pollution Sources - 451.2 Air Pollution Control - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Percentage 1.00e+00%, Percentage 9.31e+01%, Percentage 9.56e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.021

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558501
Title:Improvement and validation of bilinear surface regression model for daily evapotranspiration estimation
Authors:Shao, Yuehong (1); Liu, Yonghe (2); Wu, Junmei (3)
Author affiliation:(1) College of Hydrometeorology, Nanjing University of Information Science and Technology, Nanjing; 210044, China; (2) Institute of Resources and Environment, Henan Polytechnic University, Jiaozuo; 454000, China; (3) Kunshan Meteorological Bureaus, Kunshan; 215300, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:94-101
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The accurate estimation of potential evapotranspiration (ET<inf>0</inf>) is an important content of hydrological cycle and flux cycle, which has an important theoretical and practical significance for effective use of agricultural water resources in the context of climate change. In order to acquire stable and reliable estimation method of evapotranspiration that need only a small number of climatic factors, an improved ET<inf>0</inf>estimation method of bilinear surface regression model (BSRM) was used to calculate the daily evapotranspiration based on the observed meteorological data from 6 weather stations in the upper Yishu River watershed (34.37°-36.38°N, 117.40°-119.18°E). Three types of BSRM models were considered according to the difference in computing solar radiation in this study. In the first method, the relative insolation duration and the ET<inf>0</inf>estimation was based on the calculated solar radiation, relative humidity and air temperature (BSRM<inf>n/N</inf>). In the second method, relative humidity, air temperature and solar radiation computed by relative insolation duration and extra-terrestrial radiation were used for ET<inf>0</inf>estimation (BSRM<inf>Rs</inf>). In the third method, three variables of solar radiation computed by Hargreaves-Allen equation, relative humidity and air temperature were used for ET<inf>0</inf>estimation (BSRM<inf>t</inf>). Meanwhile, Penman-Monteith (P-M) equation was used to estimate the ET<inf>0</inf>as a reference and comparison method. The precision of the 3 kinds of BSRM approaches was tested and evaluated based the standard of land surface potential ET<inf>0</inf>calculated by the means of conversion coefficient and observed evapotranspiration. On the base of above studies, the influential factors of ET<inf>0</inf>were further analyzed. The results showed that the model precision for ET<inf>0</inf>estimation was highest in BSRM<inf>n/N</inf>, followed by BSRM<inf>Rs</inf>and BSRM<inf>t</inf>. The BSRM<inf>n/N</inf>method has the minimum mean absolute of error and root mean square of error (0.48 and 0.64 mm). The P-M equation and BSRM<inf>n/N</inf>method could yield the reliable ET<inf>0</inf>estimation, however the P-M equation could overestimate the results in daily ET<inf>0</inf>between 2-6 mm. The general tendency of ET<inf>0</inf>estimation from the 3 kinds of BSRM methods and P-M equation were consistent with that of the observation for monthly ET<inf>0</inf>, while the accuracy of ET<inf>0</inf>from BSRM<inf>n/N</inf>was closer to the observation. Studying the impacts of major meteorological factors on ET<inf>0</inf>showed that the BSRM<inf>n/N</inf>method had the least effect on the ET<inf>0</inf>, followed by BSRM<inf>Rs</inf>and BSRM<inf>t</inf>method. The simulated ET<inf>0</inf>from the BSRM<inf>n/N</inf>method was in accordance with the observed value at various relative insolation duration, relative humidity and air temperature. The underestimation and bias from BSRM<inf>t</inf>increased at the higher temperature, the lower relative insolation duration and relative humidity. The stronger wind speeded up the process of evapotranspiration. The estimated precision from the BSRM<inf>n/N</inf>model was slightly higher than the P-M model, and the former was little influenced by meteorological factors. The input meteorological variables were relatively less and convenient to obtain, which suggested that the proposed BSRM<inf>n/N</inf>model may become a stable and reliable alternative for routine daily evapotranspiration estimation in the study area. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Incident solar radiation
Controlled terms:Atmospheric temperature - Climate change - Evapotranspiration - Heat radiation - Infrared radiation - Meteorology - Radiation - Regression analysis - Solar radiation - Temperature - Water resources
Uncontrolled terms:Bilinear surface - Conversion coefficients - Daily evapotranspirations - Meteorological factors - Meteorological variables - Penman-Monteith models - Potential evapotranspiration - Terrestrial radiation
Classification code:443.1 Atmospheric Properties - 444 Water Resources - 641.1 Thermodynamics - 641.2 Heat Transfer - 657.1 Solar Energy and Phenomena - 741.1 Light/Optics - 922.2 Mathematical Statistics
Numerical data indexing:Size 2.00e-03m to 6.00e-03m, Size 4.80e-04m, Size 6.40e-04m
DOI:10.11975/j.issn.1002-6819.2017.02.013

Database:Compendex
Compilation and indexing terms, Copyright 2017 Elsevier Inc.

Accession number:20171503558498
Title:Dynamic characteristics analysis of portable twin screw air compressor system
Authors:Wu, Wanrong (1); Liang, Xiangjing (1); Lou, Lei (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Central South University, Changsha; 410083, China
Corresponding author:Liang, Xiangjing(liangxiangjing@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:73-79
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As the producer of compressed air, portable twin-screw air compressors are widely used in many industrial applications taking into account its reliability and compact feature. The compressor system is frequently operated under unload condition to achieve the air flow consumption. Under the unload condition, the air compressor still requires a lot of energy, but the air compressor stops supplying compressed air to the network. This is often ignored when studying the energy consumption of the compressor. It is important to research the dynamic performance of the portable twin-screw air compressor to reduce the energy consumption of compressor system. The system composition of portable twin-screw air compressor was described and the operating principle was analyzed. The twin-screw air compressor was divided into 3 subsystems: diesel engine, twin-screw compressor and intake valve control. For each subsystem a mathematical model was established and explained in detail. The dynamic simulation model of the portable twin-screw air compressor was implemented on the platform of MATLAB/Simulink. Three different air flow consumption loading patterns of compressor were simulated in order to understand the dynamic performance of the portable twin-screw air compressor with different air flow consumption. Some primary performance parameters of the screw compressor under load and unload conditions, such as system pressure, flow rate and shaft power, were analyzed by numerical simulations. Experimental investigation on a twin-screw air compressor under load and unload conditions was carried out to verify the integrated model. The performances of the compressor under load/unload conditions, such as system pressure and shaft power consumption, were measured with the experimental apparatus. The research results showed that the dynamic characteristics of twin-screw air compressor system under load/unload conditions were influenced by air flow consumption. According to the influence of air flow consumption on the screw compressor system, the system pressure had obvious fluctuation with the variable air flow demand pattern. The pressure change rate decreased with the increased air flow consumption. It meant that the load/unload frequency of screw compressor was reduced. When the air flow consumption was greater, the twin-screw air compressor had a greater average shaft power of system, a smaller shaft power of air flow consumption per unit and a higher energy utilization ratio. When the fluctuation range of air flow consumption was greater, the twin-screw air compressor had a greater average shaft power of system, a greater shaft power of air flow consumption per unit and a lower energy utilization ratio. Therefore, when the twin-screw air compressor runs under the load/unload conditions, it should reduce the fluctuation range of air flow consumption, and increase the air flow consumption to improve working efficiency. Simulation results are in good agreement with the experimental ones. It was shown that the error between the measured and calculated data was less than 5%. So the dynamic working process of twin-screw compressor under load/unload conditions can be predicted exactly by means of the mathematical models. Therefore, this research can be useful for energy-saving running of twin-screw air compressors. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:28
Main heading:Compressors
Controlled terms:Air - Air intakes - Compressed air - Computer simulation - Diesel engines - Energy conservation - Energy dissipation - Energy utilization - Experiments - MATLAB - Models - Pressure vessels - Thermodynamics
Uncontrolled terms:Dynamic characteristics - Dynamic characteristics analysis - Energy utilization ratio - Experimental apparatus - Experimental investigations - Operating principles - Performance parameters - Twin screw
Classification code:525 Energy Management and Conversion - 612.2 Diesel Engines - 618.1 Compressors - 619.2 Tanks - 631.1 Fluid Flow, General - 641.1 Thermodynamics - 723.5 Computer Applications - 804 Chemical Products Generally - 901.3 Engineering Research
Numerical data indexing:Percentage 5.00e+00%
DOI:10.11975/j.issn.1002-6819.2017.02.010

Accession number:20171503558492
Title:Operation parameter optimization of interrupted-whorl screw dewatering device of solid-liquid separator for livestock and poultry manure
Authors:Zhao, Weisong (1); Zhu, Dewen (1); Zong, Wenming (2); Xie, Hu (1); Cao, Jie (1); Han, Baihe (1); Li, Ruirong (1); Qu, Haoli (1)
Author affiliation:(1) Nanjing Research Institute of Agricultural Mechanization, Ministry of Agriculture, Nanjing; 210014, China; (2) School of Engineering, Anhui Agricultural University, Hefei; 230036, China
Corresponding author:Zhu, Dewen(zdwww7009@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:25-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid development of intensive livestock and poultry industry, a large amount of livestock and poultry manure is produced every year in China, which will pollute the environment if not treated properly. Chinese government carries out the environmental impact assessment for these enterprises every year, and develops strict policy to restrain the waste discharge. Solid-liquid separation is an important procedure for the follow-up comprehensive utilization of livestock manure. The existing solid-liquid separation equipment has the disadvantage of low efficiency and poor effect when processing high-concentration fecal sewage mixture. This paper designed a new type of interrupted-whorl screw solid-liquid separator with the purpose of efficiently carrying out the solid-liquid separation of high-concentration sewage, improving the separation efficiency, and producing less additional sewage. As one of the key components of the separation device, interrupted-whorl screw was designed and it includes three components, i.e. feeding section, extrusion section and discharge section. To enhance feeding capacity, continuous screw was used for the feeding section. The extrusion and discharge sections adopt the interrupted-whorl screw. The screw pitch of feeding section is 140 mm, and those of the extrusion and discharge sections are 160 mm. With high-concentration pig manure (total solid concentration 21.18%) as experimental object, this study investigated the optimization of operating parameters on self-made screw extrusion separation test bed. The Box-Behnken design method was adopted in the operating parameter optimizing experiment of the Interrupted-whole screw dewatering device. The spindle speed of screw, gap distance, and counterweight position were taken as the influencing factors, and the separation efficiency and filter cake moisture content were selected as the responsive variables in the experimental study. The quadratic regression orthogonal experiment of 3 factors and 3 levels was designed; by using the regression analysis and response surface analysis with the software of Design-Expert 8.0.6, the mathematical model concerning the 3 factors' impact on the solid-liquid separation performance was set up, and the experimental verification of the mathematical model was also conducted. The results showed that the trial factors had great effects, and the separation efficiency and the extrusion moisture content could be fitted with two regression polynomials, the P values of which were less than 0.001, indicating that the models were highly significant. The coefficients of determination (R2) were 0.984 1 and 0.983 9 respectively, which showed that 98% of the response values could be explained by the models. According to the rate of factors contribution, conclusion can be given: spindle speed > counter weight position > gap distance. This indicates that spindle speed has the greatest effect on the separation efficiency among the three selected main factors followed by counterweight position, and gap distance has the minimum effect. This conclusion is consistent with the experiment results of GuanZhengjun which extracted water of cow dung by continuous screw separator. It shows that the spindle speed has the main impact on separation efficiency whatever used for interrupted-whole screw or continuous screw.Besides, according to the contribution of filter cake moisture content, it can be ranked gap distance > counter weight position > spindle speed. It shows that in the three main factors which are selected, the gap distance has the greatest effect on the filter cake moisture content followed by counter weight position, and spindle speed has the minimum effect. In conclusion, the interrupted-whole screw has great significance on reducing the filter cake moisture content. Through the experiments combined with the actual production, the final optimal combination of working parameters was concluded, namely the distance was 37mm, the speed was 56 r/min, and the counterweight position was at the 309 mm (relative location). The values of separation efficiency and extrusion moisture content were respectively 5.43 m3/h and 53.52%, and the removal rate of suspended solids removal rate was 54.91%. Both of the relative errors between the experimental and predicted values of separation efficiency and filter cake moisture content were less than 10%, indicating that the multivariate regression model was reliable. This research provides a reference to the parameter optimization of the interrupted-whorl screw dewatering device, and helps the development of the solid-liquid separation technology of high-concentration and high-viscosity pig manure. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Screws
Controlled terms:Agriculture - Dewatering - Efficiency - Environmental impact - Environmental impact assessments - Extrusion - Feeding - Fertilizers - Filtration - Liquids - Machinery - Manures - Mechanization - Models - Moisture - Moisture determination - Optimization - Regression analysis - Separators - Sewage - Speed - Surface analysis - Verification
Uncontrolled terms:Comprehensive utilizations - Experimental verification - Multivariate regression models - Pig manures - Quadratic regression orthogonal experiments - Response surface analysis - Solid liquid separation - Total solid concentrations
Classification code:452.1 Sewage - 454.2 Environmental Impact and Protection - 601 Mechanical Design - 605 Small Tools and Hardware - 691.2 Materials Handling Methods - 721.1 Computer Theory, Includes Formal Logic, Automata Theory, Switching Theory, Programming Theory - 802.3 Chemical Operations - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes - 913.1 Production Engineering - 921.5 Optimization Techniques - 922.2 Mathematical Statistics - 944.2 Moisture Measurements - 951 Materials Science
Numerical data indexing:Percentage 1.00e+01%, Percentage 2.12e+01%, Percentage 5.35e+01%, Percentage 5.49e+01%, Percentage 9.80e+01%, Rotational_Speed 5.60e+01RPM, Size 1.40e-01m, Size 1.60e-01m, Size 3.09e-01m, Size 3.70e-02m
DOI:10.11975/j.issn.1002-6819.2017.02.004

Accession number:20171503558510
Title:Review of effects of carbon nano-materials on crop growth
Authors:Qiao, Jun (1); Zhao, Jianguo (1); Xie, Qian (2); Xing, Baoyan (1); Du, Yaqin (1); Qu, Wenshan (1); Wang, Haiqing (1)
Author affiliation:(1) College of Chemistry and Environment Engineering, Shanxi Datong University, Datong; 037009, China; (2) College of Life Sciences, Shanxi Datong University, Datong; 037009, China
Corresponding author:Zhao, Jianguo(jgzhaoshi@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:162-170
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Carbon nano-materials (CNMs) due to their unique structure and physicochemical properties are being used in the field of material science, energy, environmental remediation and medicine. As the production and application of CNMs continues to expand, CNMs will be inevitably discharged into the environment and generate unknown impacts on plants and crop species. Presently, more and more studies on CNMs are concentrated around their interactions and distribution within plants especially crops. In this paper, we review the literature about impacts on plant growth generated by four types of CNMs (carbon nanotube, fullerene, carbon nano-onions and graphene). Previous studies reveal that CNMs-exposed plants exhibit different response to stress, including seed germination, root and stem growth, biomass yields and nutritional quality. In some cases, CNMs are shown to be helpful in seed germination, root growth, photosynthesis and crop production, such as the use of fullerenes in bitter melon, the effect of graphene oxide on red bean germination, the growth promoters effects of carbon nano-onions for gram plants, the ability of carbon nanotubes to enhance growth in tobacco cells, increase the seed germination and growth of tomato plants and cause root enhancement in wheat plants. Further mechanisms investigation of CNMs on plants showed that the carbon nanotubes could increase the protein expression of water channel, as tracheal elements of the xylem vessels are responsible for water channel transport in plants, results in the overall enhanced growth of plants. While the CNMs are useful to increase the crop production and fruit manifold, but there are many other aspects, CNMs are known to be phytotoxic and harmful. Reports show that graphene significantly inhibited plant growth and biomass levels. It also decreased the number and size of leaves in a dose-dependent manner and caused oxidative stress-induced necrosis in cabbage, tomato and red spinach seeds during development. The transmission of CNMs to the next generation coming from the treated seeds has been reported, the fullerene (C<inf>70</inf>) aggregates were found in second-generation seedlings when the first generation was exposed only during germination. The ability of CNMs transmitted to the progeny suggests the potential that CNMs may present chronic exposure hazard to human and other receptors. According to the studies, the toxic effect of CNMs on plants seems to be related to the nano-materials' concentration, the exposure time and the plant species used during the study. When nano-carbon was added to the fertilizer, nano-fertilizer was formed. Compared with the conventional fertilizer, the nanocarbon-synergistic fertilizer had the function of promoting the growth of the crops, nutrients content and fertilizer agronomic efficiency. The nano-synergistic fertilizer increased the rice yield of 10.3%, the spring maize of 10.9%-16.7%, the soybean of 28.8% and increased the soybean oil content of 13.2%. Nano-fertilizer also could improve the quality of the vegetables; the content of anthocyanin of summer radish was increased and the peel color turned prunosus. The amino acid content of celery treated with nano-synergistic fertilizer was shown to be 15.4%-70.0% higher than that with urea treatment. Compared to urea application alone, the nano-carbon fertilizer synergist was found to be able to improve N agronomic efficiency by 40.1% while minimizing N losses when added into urea. The mechanism of nano-synergistic fertilizer on crops showed that nano-carbon mixed with water became the superconductor, which increased the electric potential of soil and release large amounts of nutrient elements. However, it is still not fully understood how these actions induced by CNMs. Given the potential widespread application of nanotechnology in agriculture, resolution of this question remains a critical issue of concern. Importantly, more research is urgently needed in the area of CNMs-plant interactions; and with this fundamental knowledge, development of novel idea and guidance for implementation of CNMs in agriculture and food manufacturing will be possible. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:68
Main heading:Seed
Controlled terms:Agriculture - Agronomy - Anthocyanins - Carbon nanotubes - Crops - Cultivation - Ecology - Electric potential - Fertilizers - Fruits - Fullerenes - Graphene - Growth (materials) - Image quality - Industrial research - Metabolism - Nanotechnology - Nanotubes - Nutrients - Oils and fats - Plants (botany) - Soybean oil - Toxic materials - Urea - Yarn
Uncontrolled terms:Carbon nano-materials - Dose-dependent manner - Environmental remediation - Nano-carbon - Nutritional qualities - Physicochemical property - Plant interactions - Protein expressions
Classification code:454.3 Ecology and Ecosystems - 701.1 Electricity: Basic Concepts and Phenomena - 761 Nanotechnology - 804 Chemical Products Generally - 804.1 Organic Compounds - 819.4 Fiber Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 951 Materials Science
Numerical data indexing:Percentage 1.03e+01%, Percentage 1.09e+01% to 1.67e+01%, Percentage 1.32e+01%, Percentage 1.54e+01% to 7.00e+01%, Percentage 2.88e+01%, Percentage 4.01e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.022

Accession number:20171503558528
Title:Surface enhanced Raman scattering detection of mixing pesticide residual on orange peel
Authors:Wang, Haiyang (1); Liu, Yande (1); Zhang, Yuxiang (1)
Author affiliation:(1) Institute of Optics-Mechanics-Electronics Technology and Application, School of Mechanotronics & Vehicle Engineering, East China Jiaotong University, Nanchang; 330013, China
Corresponding author:Liu, Yande(jxliuyd@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:291-296
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, pesticide has been mass-producing and widely used. The problem of pesticide residues has attracted more and more attention. As the problem of food safety is becoming the focus of society, the pesticide residue detection has become a research hotspot. Among numerous methods of pesticide detection, surface-enhanced Raman spectroscopy (SERS) has become an area of intense research owing to a highly sensitive probe for the trace level detection of pesticide. The spectroscopic merits of SERS are the representation in the aspects of super sensitivity, high selection and water resistance, which make it one of the most popular detection techniques currently. In this paper, the organophosphorus pesticide phosmet and dimethoate were selected as the research objects. The blended pesticide residues of phosmet and dimethoate on navel orange were detected by the SERS combined with chemometrics algorithm. The silver nanowires were used as SERS substrate to detecte pesticide residue on navel orange. Firstly, the navel orange samples were fabricated with pesticide residues. Secondly, the silver nanowires SERS substrate was fabricated. Then the sample solution to be measured was dripped onto the dried SERS substrate. When the sample was dried, spectral data were collected. The spectral data were used to analyze pesticide residue qualitatively and quantitatively. It had a better enhancement effect on the qualitative analysis of mixing pesticides for silver nanowires substrate. Pesticide original spectral data were processed by the partial least square (PLS) modeling algorithm and the different pretreatment methods. The PLS regression combined with different data preprocessing methods was used to develop quantitative models of mixing pesticide residue. And the advantages and disadvantages of the models were compared. The results showed that the model built by the PLS combined with the second derivatives data preprocessing was ideal for mixing pesticides, whose correlation coefficient (R<inf>p</inf>) for the prediction was 0.954, and root mean square error of prediction (RMSEP) was 4.822 mg/L. The model combined with the baseline was ideal for phosmet, whose R<inf>p</inf>was 0.898 and RMSEP was 6.621 mg/L. The model combined with the multiplicative scattering correction (MSC) was ideal for dimethoate, whose R<inf>p</inf>was 0.911 and RMSEP was 7.369 mg/L. Therefore, the study combines the SERS and chemometrics algorithm to detect pesticide residues qualitatively and quantitatively, which is feasible. Raman spectroscopy can be used as a fast and simple tool to detecte mixing pesticide residues. It provides a basis for the more insightful study on pesticide residues detection. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Pesticides
Controlled terms:Chemical contamination - Citrus fruits - Electric resistance measurement - Food safety - Least squares approximations - Light transmission - Mean square error - Mixing - Models - Nanowires - Principal component analysis - Raman scattering - Raman spectroscopy - Silver - Spectrum analysis - Substrates - Surface scattering
Uncontrolled terms:Correlation coefficient - Multiplicative scattering corrections - Organophos-phorus pesticides - Partial least square (PLS) - Root-mean-square error of predictions - Surface enhanced Raman Scattering (SERS) - Surface enhanced Raman spectroscopy - Trace-level detection
Classification code:547.1 Precious Metals - 741.1 Light/Optics - 761 Nanotechnology - 802.3 Chemical Operations - 803 Chemical Agents and Basic Industrial Chemicals - 821.4 Agricultural Products - 822.3 Food Products - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 931 Classical Physics; Quantum Theory; Relativity - 933 Solid State Physics - 942.2 Electric Variables Measurements
Numerical data indexing:Mass_Density 4.82e-03kg/m3, Mass_Density 6.62e-03kg/m3, Mass_Density 7.37e-03kg/m3
DOI:10.11975/j.issn.1002-6819.2017.02.040

Accession number:20171503558497
Title:Improved active disturbance rejection controller on suspension system and its performance analysis
Authors:Huang, Dashan (1); Zhang, Jinqiu (1); Liu, Yile (1); Bi, Zhandong (1)
Author affiliation:(1) Department of Equipment Testing & Training, Academy of Armored Force Engineering, Beijing; 100072, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:61-72
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To solve the problem of the contradiction of improving riding comfort and handling stability of suspension system at the same time with active control algorithm, the active disturbance rejection control was selected and improved to lower suspended mass acceleration and dynamic load of tire of suspension system simultaneously after the consideration and comparison of 4 kinds of control algorithms, which were based on state, classic control theory, optimal control theory and intelligent optimization theory, respectively. Suspended mass acceleration and dynamic load of tire were combined as the feedback signal, which was compared with the reference input signal to generate the state error, and then a nonlinear state error feedback control law was provided which took all the terms of proportion, integration and differentiation of state error into consideration. A comprehensive performance assessment criterion on suspension system was established considering both suspended mass acceleration and dynamic load of tire, and it could be used to assess the effectiveness of the improvements on suspension system comprehensive performance with the improved control algorithm. The formula of comprehensive performance assessment criterion was established based on quartic power function, which could magnify the effect of control algorithm on different vibration features of suspension system and different riding performances of vehicle. Then a parameter tuning method of the improved active disturbance rejection controller was stated based on the analysis on the functions and influences of different parameters, the reference ranges of which were provided for effective design of control algorithm. Simulations were made to compare and analyze the performance of the standard skyhook active control suspension system, the standard active disturbance rejection control suspension system and the improved active disturbance rejection control suspension system. The results showed that: 1) Both suspended mass acceleration and dynamic tire deformation of suspension system were reduced by 17.68% and 1.78%, the riding comfort and handling stability of vehicle were more advanced with the improved active disturbance rejection control compared with the standard skyhook active control and the standard active disturbance rejection control, and the comprehensive performance of vehicle with the improved active disturbance rejection control was much better than that with the other two; 2) As to the analysis in frequency domain, the transmissibility of suspended mass acceleration of suspension system with the improved active disturbance rejection control could be depressed in low resonance frequency range, medium frequency range and high frequency range, and both the transmissibility of dynamic tire deformation and the suspension working space with that could be suppressed in low resonance frequency range, which were the major working ranges in improving the transmissibility of suspension system; 3) All the relative fluctuations of riding comfort, handling stability and comprehensive performance of vehicle with the improved active disturbance rejection control algorithm were less than 2%, 4% and 2% respectively as the variation of suspended mass, road excitation level and vehicle velocity, which indicated the robustness of the improved active disturbance rejection control was the strongest one among them. Bench tests of suspension system were conducted to compare and analyze the performances of the passive suspension system and the improved active disturbance rejection control suspension system. The results showed that: 1) All the measured data were a litter larger than the simulation data because of the differences between simulation parameters and bench parameters, the measurement noise and the non-adhesive feature between the springs and the masses; 2) Both suspended mass acceleration and dynamic tire deformation of suspension system were lowered with the improved active disturbance rejection control in experimentation, and the comprehensive performance of vehicle was improved remarkably, which fitted the simulation results; 3) All the relative fluctuations of comprehensive performance of vehicle with the improved active disturbance rejection control were lower than 3% as the variation of suspended mass, road excitation level and vehicle velocity, which demonstrated the strong robustness of the improved active disturbance rejection control algorithm. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:31
Main heading:Suspensions (components)
Controlled terms:Acceleration - Active suspension systems - Advanced vehicle control systems - Algorithms - Automobile suspensions - Control - Control system stability - Control theory - Controllers - Deformation - Disturbance rejection - Dynamic loads - Errors - Feedback - Frequency domain analysis - Magnetic levitation vehicles - Natural frequencies - Optimization - Parameter estimation - Resonance - Roads and streets - Robustness (control systems) - Site selection - System stability - Tires - Vehicle performance - Vehicles - Velocity control - Vibrations (mechanical)
Uncontrolled terms:Active control - Active disturbance rejection controller - Active disturbance rejection controls - Comprehensive performance - Comprehensive performance assessments - Improved control algorithms - Nonlinear state error feedbacks - Suspension system
Classification code:406.1 Highway Systems - 406.2 Roads and Streets - 408.1 Structural Design, General - 601.2 Machine Components - 662.1 Automobiles - 662.4 Automobile and Smaller Vehicle Components - 731 Automatic Control Principles and Applications - 732.1 Control Equipment - 818.5 Rubber Products - 921.3 Mathematical Transformations - 921.5 Optimization Techniques - 931.1 Mechanics - 961 Systems Science
Numerical data indexing:Percentage 1.77e+01%, Percentage 1.78e+00%, Percentage 2.00e+00%, Percentage 3.00e+00%, Percentage 4.00e+00%
DOI:10.11975/j.issn.1002-6819.2017.02.009

Accession number:20171503558514
Title:Calculation method of rice canopy leaf area based on virtual model
Authors:Ding, Weilong (1); Xie, Tao (1); Xu, Lifeng (1); Zhang, Yikai (2)
Author affiliation:(1) College of Computer Science & Technology, Zhejiang University of Technology, Hangzhou; 310023, China; (2) State Key Laboratory of Rice Biology, China National Rice Research Institute, Hangzhou; 310006, China
Corresponding author:Zhang, Yikai(yikangzhang168@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:192-198
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Leaf area of the rice canopy is one of the key parameters for rice research and management. Analysis of intercepted light of the rice population and development of the light distribution model based on leaf area analysis on different layers are of great importance. The traditional calculation methods for leaf area are inefficient and with significant bias. Besides, the processes of leaf acquisition often cause damage to the plant, and measurements of the leaf area in different layers are with difficulty. To overcome the weakness of traditional statistical method for leaf area of rice canopy, a new method based on virtual plant model was proposed to calculate the leaf area of rice. The field experiment was firstly conducted to obtain the rice morphological parameters, which were used in the establishment of the virtual rice model. We used two curve equations to construct the profile of the blade. A variety of rice leaves was selected as a sample, and then we analyzed the relationship between contour curve equation parameters and leaf shape parameter by MATLAB. In this way, we can determine the parameters of the virtual leaf contour curve equation. Secondly, we used cylinder with different upper and bottom surfaces to simulate the stem of rice based on the data from field experiment. We constructed the virtual rice model according to the topological structure of leaves and stems. The model was then used to calculate the leaf area for the leaves from different height ranges within the rice canopy, for which the rice individuals were cultivated under different distances, and thus to further support optimization processes for rice cultivation and management. Furthermore, we also calculated the leaf area of a rice using the virtual rice model, and construct different types of virtual rice according to the input parameters. The proposed algorithms were verified with the experiment data. The results of leaf areas obtained from field experiments and virtual plants were compared, which were basically consistent and with minor bias. The leaf area of each plant was measured with the method of the length-width, and that were compared with the simulation results. The calculated results between the algorithms proposed in this paper and the method of the length-width correction differed in 5%. For the stratified leaf area calculation part, the canopy of the selected rice sample was divided into three layers, and the effectiveness of the simulation results was verified by measuring the area of the leaf fragments of the different layers. The actual measurement results of the leaf area of each layer and the simulation results of the algorithm were compared, and the error was within 10%. The method can realize the measurement without destroying the plant, and eliminate the influence of the experiment on the natural environment in the real scene, and reduce the manpower and material resources needed to measure the leaf area and improve the efficiency. This method has a certain practical significance for the rice canopy leaf area statistics. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:27
Main heading:Plants (botany)
Controlled terms:Crops - Flow visualization - MATLAB - Models - Optimization - Topology
Uncontrolled terms:Actual measurements - Leaf area - Light distribution models - Morphological parameters - Natural environments - Rice-model - Topological structure - Virtual plant model
Classification code:631.1 Fluid Flow, General - 821.4 Agricultural Products - 921 Mathematics
Numerical data indexing:Percentage 1.00e+01%, Percentage 5.00e+00%
DOI:10.11975/j.issn.1002-6819.2017.02.026

Accession number:20171503558503
Title:Complex ameliorants screening for reducing swelling ratio and improving shear strength of strong expansive soil
Authors:Shen, Taiyu (1); Xing, Shuxiang (1); Wang, Shiji (1); Cheng, Mingshu (1); Huang, Wei (1)
Author affiliation:(1) College of Engineering and Technology, Southwest University, Chongqing; 400716, China
Corresponding author:Wang, Shiji(shjwang@swu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:109-115
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:More than 5 billion dollars economic loss is caused by expansive soil each year around the world. Soil chemical amelioration is better than the other methods, but better effect and higher safety cannot be achieved by a single ameliorant. In order to weaken serious damages to civil engineering facilities and agricultural ecological environment induced by expansive soils, composed ameliorants to improve the expansive soil were tested in laboratory tests in this paper. The low free swelling ratio (no more than 40%) and the high shear strength were required for the soil amendment. Expansive soil used for testing was collected from Handan in Hebei province in China. It was a strong expansive soil with 130% free swelling ratio (more than 90%) and contained large hydrophilic minerals. Based on the physical-chemical effect of ion exchange (to decrease thickness of hydration shell), polymer film-forming effect (to prevent hydrone from permeating clay particle) and so on, the combinations of different ratios of CaO (1%-8%), KCl(3%-10%), PVA(0.3%-1.0%), polypropylene fiber(0.2%, 0.4%, 0.6%, 0.8%, 1.0%) were used to treat expansive soils. Based on the construction safety and experiment error, among 54 groups of free expansion ratio tests (using for measuring free swelling ratio), 5% KCl+0.8% PVA and 4% CaO+0.8% PVA had better improvement effect, and they were chosen for testing shear strength. A total of 5 groups were designed in triaxial compression tests: no amendment, 0.6% polypropylene fiber, 5% KCl+0.8% PVA, 5% KCl+0.8% PVA+0.6% polypropylene fiber, 4% CaO+0.8% PVA. They were tested for studying improvement effect by measuring axial force, axial strain and shear strength. The results showed that the improvement effects of composite ameliorants were remarkable. The free swelling ratio was reduced to 27% from 130%, and the shear strength was increased 15% by using the mixed solution of 0.8% PVA+ 5% KCl+0.6% polypropylene fiber. The free swelling ratio was reduced to 33% from 130%, and shear strength was increased 110% by using the mixed solution of 0.8% PVA+4% CaO. In addition, the research showed that the reduction of expansion rate due to adding KCl or CaO was reinforced by the film-effect of PVA and the increase of shear strength due to adding polypropylene fiber was weekend by KCl and PVA. Crack initiation of expansive soil was effectively reduced by adding polypropylene fiber and shear strength was improved too. The effectiveness of composed improvement methods of strong expansive soil was validated by the laboratory tests. The promotion and inhibition mechanism needs further research. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:24
Main heading:Shear strength
Controlled terms:Compression testing - Fibers - Ion exchange - Losses - Plastic products - Polymer films - Polypropylenes - Polyvinyl alcohols - Reinforced plastics - Safety engineering - Safety testing - Semiconducting films - Shear flow - Soil testing - Soils - Swelling
Uncontrolled terms:Chemical amelioration - Ecological environments - Expansive soils - Film effects - Improvement methods - Inhibition mechanisms - Swelling ratio - Tri-axial compression tests
Classification code:483.1 Soils and Soil Mechanics - 631.1 Fluid Flow, General - 712.1 Semiconducting Materials - 802.2 Chemical Reactions - 815.1 Polymeric Materials - 815.1.1 Organic Polymers - 817.1 Polymer Products - 911.2 Industrial Economics - 914 Safety Engineering - 914.1 Accidents and Accident Prevention - 951 Materials Science
Numerical data indexing:Percentage 1.00e+00%, Percentage 1.00e+00% to 8.00e+00%, Percentage 1.10e+02%, Percentage 1.30e+02%, Percentage 1.50e+01%, Percentage 2.00e-01%, Percentage 2.70e+01%, Percentage 3.00e+00% to 1.00e+01%, Percentage 3.00e-01% to 1.00e+00%, Percentage 3.30e+01%, Percentage 4.00e+00%, Percentage 4.00e+01%, Percentage 4.00e-01%, Percentage 5.00e+00%, Percentage 6.00e-01%, Percentage 8.00e-01%, Percentage 9.00e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.015

Accession number:20171503558517
Title:Quantitative assessment and screening of images in lighting environment of typical piggery
Authors:Du, Xiaodong (1); Teng, Guanghui (1); Li, Zhuo (1); Shi, Chen (1)
Author affiliation:(1) College of Water Conservancy and Civil Engineering, China Agricultural University, Key Laboratory of Agricultural Engineering in Structure and Environment, Beijing; 100083, China
Corresponding author:Teng, Guanghui(futong@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:213-219
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the advancement of digital agriculture, researching on pig weight estimation by using machine vision technology has become one of hotspots. The outside light environment of machine vision has a great influence on the quality of captured images. Ignoring the significance of lighting system, majorities of studies on pig weight estimation focused on algorithms and image processing without quantitative assessment methods of light environment. This research focus on the light environment for machine vision in typical piggery and the purpose is to explore a method to achieve effectively screening images taken by monitoring platform to filter out a large amount of invalid images interfered by outside light environment. This paper, based on pig weight monitoring platform, LabVIEW software was used to analyze the image quality of actual light environment condition. Researches consisted of field test and laboratory test. Light measurement of region of interest was mainly carried out in field test during different breeding periods as well as with different heights of pig body. Laboratory test was divided into two parts. One was the calibration of light sensor and the other was image processing for comparing the difference between the algorithm value and the real value. Experiments were carried out in the experimental station of Shangzhuang of China Agricultural University and the test objects were 5 heads of castration landrace. AS813 illuminance meter of SMART SENSOR Company was used to conduct research in test spot. In order to ensure the data accuracy, it was conducted two times of sensor calibration. The analysis of uniformity of illumination in measurement area was referred to lighting engineering standards for evaluating the intensity of illumination evenness. U<inf>1</inf>and U<inf>2</inf>parameters were used to evaluate evenness index of illumination intensity. U<inf>1</inf>is the ratio of the minimum illuminance and the maximum illuminance. U<inf>2</inf>is the ratio of the minimum illuminance and the average illuminance. By means of computer software program, it could replace artificial measures to realize the measurement of illumination simulation values, the gray level change rate and image exposure judgement parameters. After on-site validation experiments as well as data analysis, it had not significant difference among light measurements of various height of pig body during breeding period. Also, it had no obvious difference between measured value and simulation value. The correlation coefficient of U<inf>1</inf>between measured value and simulation value is 0.791 and the correlation coefficient of U<inf>2</inf>between measured value and simulation value is 0.853. Replacing measured values, simulation can fast achieve the distribution of the light environment approximately. Illumination correction coefficient τ was put forward in order to ensure the validity of the data, reflect the true light environment and make up for 20% relative error of the measurement instrument. In addition, it is obviously different among ideal image, overexposed image, natural light image and Yin and Yang image in the parameters of exposure and uniformity ratio of illumination: the illumination uniformity parameters of ideal image and overexposed image meet the requirement of standards of illuminating engineering, and the normal rate of exposure for ideal image rate is higher. The illumination uniformity parameters of natural light image and Yin and Yang image did not meet the requirements of standards of illuminating engineering. Judgment standards of normal exposure were determined at U<inf>1</inf>>0.7 and U<inf>2</inf>>0.8 to realize the filter of ideal image which is convenient for researchers screening out ideal image. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Image processing
Controlled terms:Agricultural machinery - Agriculture - Calibration - Computer programming languages - Computer software - Computer vision - Illuminating engineering - Image segmentation - Light measurement - Lighting - Mammals - Monitoring - Standards
Uncontrolled terms:Illuminance - LabViEW - Lighting environment - Pig weight - Uniformity ratio of illuminance
Classification code:707 Illuminating Engineering - 723 Computer Software, Data Handling and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.1 Agricultural Machinery and Equipment - 902.2 Codes and Standards - 941.4 Optical Variables Measurements
Numerical data indexing:Percentage 2.00e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.029

Accession number:20171503558515
Title:Kiwifruit recognition method at night based on fruit calyx image
Authors:Fu, Longsheng (1); Sun, Shipeng (1); Manuel, Vázquez-Arellano (2); Li, Shifeng (1); Li, Rui (1); Cui, Yongjie (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&F University, Yangling; 712100, China; (2) Institute of Agricultural Engineering, University of Hohenheim, Stuttgart; 70599, Germany
Corresponding author:Cui, Yongjie(cuiyongjie@nwafu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:199-204
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China is the largest country for cultivating kiwifruits, and Shaanxi Province provides the largest production, which accounts for approximately 70% of the nationwide production and 33% of the global production. Harvesting kiwifruits in this region relies mainly on manual picking which is labor-intensive. Therefore, the introduction of robotic harvesting is highly desirable and suitable. Most researches involved so far in kiwifruit harvesting robots suggest the scenario of daytime harvesting for taking advantage of the sunlight. Robot picking at night can overcome the problem of low work efficiency and will help to minimize fruit damage. In addition, artificial lights can be used to ensure constant illumination instead of the variable natural sunlight for image acquisition. The study object of this paper was a kiwifruit recognition system at night using artificial lighting by identifying the fruit calyx. According to kiwifruits' growth characteristics, which were grown on sturdy support structures, an RGB (red, green, blue) camera was placed underneath the canopy so that kiwifruits clusters could be included in the images. An image processing algorithm was developed to recognize kiwifruits by identifying the fruit's calyx. Firstly, it subtracted 1.1R-G gray image, and then segmentation was done using the Otsu method for the thresholding. A morphological operation was applied to remove the noise that adhered to the target fruits (such as branches). Afterwards, an area thresholding method was employed to eliminate the remaining noises. This method is based on finding the biggest area of neighboring white pixels in the image and eliminating all areas which are smaller than 1/5 of the biggest area. Using this image as the mask, a fruit image without background was obtained. After that, V (value) component of HSV (hue, saturation, value) color model was calculated for segmenting the fruit's calyx from the fruit, also using the Otsu method for thresholding. Black areas were then labeled and sorted by their pixels numbers. The first largest black area was the image background and the second largest black areas was a fruit calyx area that used as the reference area. Since the fruit calyx areas varies in a small range in one image, the fruit calyx areas are judged by comparing with the reference area. If a black area in the image was smaller than the reference area and larger than 1/10 of the reference area, it is a fruit calyx; otherwise, it is not. Finally, the nearest edge pixel for each fruit's calyx was searched and their distance calculated was as radius, and a circle around the fruit calyx was drawn. Finally, the algorithm was also tested for the robustness under 12 different light illuminations (10, 30, 50, 80, 110, 150, 200, 300, 400, 500, 800 and 1 200 lux). The fruits illumination was estimated by averaging the illumination values, which were measured for 3 times at 3 different locations around the target fruit cluster. Results showed that the image processing algorithm based on the calyx could recognize kiwifruit and reached a success rate of 94.3%. Undetected and wrongly detected fruits appeared mostly at the same cluster where one fruit was adjacent to 3 or more fruits. The calyxes of those fruits sometimes were not in the centers of their fruits' images, thus, causing undetected fruits. Those fruits also formed dark areas among them, which were wrongly recognized as calyx. On the other hand, most clusters were linearly arranged on the branches, which made them suitable for the proposed algorithm. The algorithm was robust to different illuminations although the success rates were slightly decreased under extremely weak or strong illuminations. It only took 0.5 s in average to recognize a fruit, which is a great step toward filed robotic harvesting of kiwifruit. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:29
Main heading:Fruits
Controlled terms:Clustering algorithms - Crops - Harvesting - Image processing - Image recognition - Image segmentation - Mathematical morphology - Pixels - Robotics - Robots
Uncontrolled terms:Artificial lighting - Growth characteristic - Image processing algorithm - Kiwifruits - Morphological operations - Night recognition - Recognition methods - Thresholding methods
Classification code:731.5 Robotics - 821.3 Agricultural Methods - 821.4 Agricultural Products - 903.1 Information Sources and Analysis
Numerical data indexing:Illuminance 1.20e+03lx, Illuminance 8.00e+02lx, Percentage 3.30e+01%, Percentage 7.00e+01%, Percentage 9.43e+01%, Time 5.00e-01s
DOI:10.11975/j.issn.1002-6819.2017.02.027

Accession number:20171503558506
Title:Effect of simulated rainfall intensities and underground pore fissure degrees on soil nutrient loss from slope farmlands in Karst Region
Authors:Peng, Xudong (1); Dai, Quanhou (1); Li, Changlan (1); Yuan, Yingfei (1); Zhao, Longshan (1)
Author affiliation:(1) College of Forestry, Guizhou University, Guiyang; 550025, China
Corresponding author:Dai, Quanhou(qhdairiver@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:131-140
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Karst, which is characterized by a double-layer structure of surface and underground spaces, is a landscape formed through dissolution of soluble rocks, including limestone, dolomite and gypsum. Due to interaction of natural factors and human activities, the surface presents rocky desertification landscape with shallow soil layer, discontinuous regolith and even large area bare rocks, meanwhile, the underground space is characterized by sinkholes, closed depressions, subterranean drainage, caves and fissures. Undoubtedly, rainfall intensity acts as a driving force for surface and underground runoff and sediment yield. Underground pore fissure is an important way of soil and water loss on slope in Karst Region. Due to the difficulty in measuring underground leakage of soil and water in the underground space, there is very little study on the underground pore fissure leakage of soil nutrients in Karst Region. Therefore, people's understanding on rainfall intensity and underground pore fissure influencing soil nutrients loss is not enough in Karst Region. This paper aimed to study the effect of rainfall intensities and underground pore fissure degrees on nitrogen, phosphorus and potassium loss in runoff and sediment from slope farmland in Karst Region using the method of artificial simulation rainfall experiments. A steel tank (length of 4.0 m× width of 1.5 m× depth of 0.35 m) was built to simulate the surface micro-topography and underground pore fissure characteristics of karst slope in laboratory. Results indicated that: 1) Rainfall intensity had a significant (P<0.05) impact on surface runoff and sediment yield, and the runoff depth and sediment yield increased with the increase of rainfall intensity. The critical rainfall intensity for yielding surface runoff and sediment changed between 30 mm/h and 50 mm/h. Underground pore fissure degree had no obvious changes with surface and underground runoff and sediment yield. Specifically, soil erosion type on karst slope farmland was a process of transition from underground leakage to surface erosion. Total runoff yield was dominated by underground runoff, but total sediment production was dominated by surface sediment on slope farmland in Karst Region. 2) Except for surface runoff yield events, rainfall intensity showed certain effects on nutrients concentration of surface runoff and sediment, in which total nitrogen (TN) and total potassium (TK) concentration of surface runoff decreased with rainfall intensity increasing while TN concentration of surface sediment increased with increasing rainfall intensity. Under same conditions, a few differences in TN and total phosphorus (TP) concentrations were measured between surface runoff and underground runoff. However, the TK concentration in surface runoff was higher than underground runoff, which indicted that potassium was prone to loss with surface runoff. 3) Rainfall intensity had significant (P<0.05) effects on load of nutrients loss in surface runoff, load of TN loss in underground runoff and total load of TN loss in runoff. Meanwhile, underground pore fissure degree also had a significant (P<0.05) effect on load of TN loss in underground runoff while had no obvious effect on load of TP and TK in underground runoff, load of nutrients in surface runoff and total load in runoff. Total load of nutrients loss for TN and TP were dominated by losing in runoff, but total load of TK loss was dominated by losing in sediment on karst slope. In a word, rainfall intensity was an important influence factor of soil nutrient loss on karst slope. Underground pore fissure degree had little effect on soil nutrient loss but it was the main way of soil nutrient loss on karst slope farmland. These results of this study could provide some basic parameters and scientific basis for revealing the mechanism and controlling beginning of soil nutrients loss on karst slope farmland. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:34
Main heading:Nutrients
Controlled terms:Erosion - Farms - Landforms - Loads (forces) - Nitrogen - Phosphorus - Potassium - Rain - Runoff - Sediments - Soils - Surficial sediments
Uncontrolled terms:Artificial simulation - Critical rainfall intensities - Double layer structure - Karst slopes - Nutrients concentrations - Rainfall intensity - Surface runoff yields - Underground pore fissure degree
Classification code:408 Structural Design - 442.1 Flood Control - 443.3 Precipitation - 481.1 Geology - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 549.1 Alkali Metals - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
Numerical data indexing:Size 3.50e-01m
DOI:10.11975/j.issn.1002-6819.2017.02.018

Accession number:20171503558526
Title:Establishment and application of iZone system for intelligently identifying preserved zones of permanent prime farmland
Authors:Ma, Shifa (1); Wu, Kaizhao (1); Lao, Chunhua (2); Zhong, Yuanjun (1); Zhang, Ting (1); Huang, Tao (1)
Author affiliation:(1) Land and Resources Technology Center of Guangdong Province, Guangzhou; 510075, China; (2) School of Management Guangdong University of Technology, Guangzhou; 510520, China
Corresponding author:Lao, Chunhua(chanverlao@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:276-282
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China has fed about 20% of the world population with only 8% of the world land. Actually, the proportion of arable land is much lower than 8% because most of the land is unavailable for agriculture activity, such as mountains, deserts and so on. Since the reform and opening-up policy was proposed in 1978, China has undergone rapid urbanization, which has become a great threat to food security. In this case, Chinese government proposed a new policy about protection of permanent basic farmland in response to the increasing urban growth. It is important and urgent to zone the permanent farmland for restraining the pell-mell urban expansion and improving the protective efficiency, which is of great significance to food security for China. Whether the basic farmland protection is permanent or not, the core problem is to identify which arable land should be protected. In general, the core elements for identifying permanent basic farmland are the quality and the spatial pattern of arable land, which mainly determines the zoning pattern of permanent basic farmland protection. This aims to contradict the conflicts between farmland protection and urban growth. And there are many objectives should be considered when identifying the permanent basic farmland in actual engineering practice. For example, a contiguous pattern is more preferred for modernizing the agricultural sector. Therefore, it is a complex data mining problem to identify and zone permanent basic farmland from land-use status quo database. In this paper, the result of farmland utilization grade was applied to measure the quality of arable land. Cellular automata was further developed to simulate the conflict between farmland protection and urban growth, and then the arable lands located within the simulated growth area can be easily detected and excluded from protection. However, those arable lands around cities and traffic lines with the high quality may be also allowed for urban growth. This may disobey the new policy of farmland protection enacted by government. Whether the arable lands of high quality around cities and traffic lines are protected or not is greatly determined by local government. In order to zone the plausible protection pattern, a seed search algorithm was improved and induced. A series of factors including the quality of arable land, coordinated pattern of urban growth, landscape connectivity of zoned protection area, and topographic constraints were further incorporated to derive the relatively best protection pattern. Moreover, artificial neural network algorithm was used to forecast the protection stress of basic farmland due to the increasing urban expansion. An intelligent zoning tool (iZone) was developed using the component technology of ArcGIS and C#. This tool was used to identify universe basic farmlands with the integration of the above mentioned data mining models. Jinli town of Gaoyao district located in Guangdong province was further selected as a case study area to test the iZone's performance. The quantitative comparison between the pattern identified by expert's work and that obtained by iZone was also carried out. Results demonstrated that iZone can retrieve a better protection pattern of permanent basic farmland from land-use status quo database, which can efficiently avoid the subjectivity of artificial work. iZone can identify the permanent basic farmland under the support of complex geographic computation technologies. It is of some practicability in decision-making for permanent basic farmland protection. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:26
Main heading:Farms
Controlled terms:Agriculture - Arid regions - Cellular automata - Complex networks - Data mining - Decision making - Deep neural networks - Food supply - Geographic information systems - Identification (control systems) - Land use - Neural networks - Public policy - Seed - Urban growth - Zoning
Uncontrolled terms:Artificial neural network algorithm - Component technologies - Engineering practices - Landscape connectivities - Prime farmlands - Protective efficiency - Quantitative comparison - Topographic constraints
Classification code:403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 443 Meteorology - 444 Water Resources - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 822.3 Food Products - 903.3 Information Retrieval and Use - 912.2 Management - 921 Mathematics - 971 Social Sciences
Numerical data indexing:Percentage 2.00e+01%, Percentage 8.00e+00%
DOI:10.11975/j.issn.1002-6819.2017.02.038

Accession number:20171503558507
Title:Effects of vegetation construction on soil and water conservation in small watershed of purplish soil region, northern Sichuan
Authors:Zheng, Jiangkun (1, 2); Li, Jingyuan (1, 2); Qin, Wei (3, 4); Shan, Zhijie (3, 4); Li, Bai (3, 4); Lang, Dengxiao (1); Ma, Xing (1); Liao, Feng (1)
Author affiliation:(1) College of Forestry, Sichuan Agricultural University, Chengdu; 611130, China; (2) Key Laboratory of Soil and Water Conservation & Desertification Combating of Colleges and Universities in Sichuan Province, Chengdu; 611130, China; (3) State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing; 100048, China; (4) Research Center on Soil and Water Conservation of the Ministry of Water Resource, Beijing; 100048, China
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:33
Issue:2
Issue date:January 15, 2017
Publication year:2017
Pages:141-147
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Purple soil is thin in depth and its corrosion resistance is poor. Coupled with heavy and concentrated rainfall and severe human disturbance, soil erosion is very serious. In recent decades, especially later 1980s, projects of forestry ecological engineering have been implemented in the area, which has brought remarkable ecological benefit. It is important for watershed manager to quantitatively evaluate soil and water conservation function of vegetation construction. Based on daily rainfall, daily runoff and daily sediment yield during 1985-2001 in Hemingguan watershed II of northern Sichuan, the change trends of runoff and sediment were analyzed by Spearman's correlation analysis. Moreover, the effect of soil and water conservation of vegetation construction was evaluated quantitatively using the methods of double mass curve and flow duration curve. The results showed that the reference period (1985-1990) and the evaluation period (1991-2001) were separated from the hydrological sequences according to the result of double mass curve and the implement time of vegetation construction. Compared with the reference period, annual runoff depth and annual sediment delivery modulus reduced by 34.6% and 89.9% in the evaluation period, whereas annual rainfall only reduced by 8.1%. It was illustrated that vegetation construction, as the main part of human activity, played an important role for runoff and sediment reduction. With forest vegetation restoring, more and more rainfall was intercepted by canopy and litter of forest. Then the intercepted water was translated into vapor by evapotranspiration of forestland or groundwater through infiltration. If annual rainfall remained unchanged, surface runoff turned smaller as evapotranspiration grew up. Simultaneously, with forest vegetation construction, forest vegetation reduced soil erosion with the improvement of root fixation, soil structure and infiltration rate. Terrain roughness was another cause to reduce soil erosion accompanied by surface runoff. The forest vegetation might control surface runoff by lush foliage and huge root system. High flow and normal flow during the evaluation period reduced by 84.2% and 76.3% compared to those during the reference period. Nevertheless, low flow increased by 650.0%. Vegetation construction obviously reduced high flow and increased low flow. The rainfall infiltration capacity of watershed underlying surface was enhanced by the vegetation construction, which increased the rainfall infiltration content and runoff interception, and delayed the formation of runoff. Therefore, high flow turned to smaller during the period of vegetation construction. In drought period, the water stored in soil and groundwater began to be released to feed low flow. For forest watershed, a large amount of water was restored under the surface, which might provide more water than bare watershed. So, in the period of vegetation construction, low flow showed an increasing trend instead of decreasing. Combining double mass curve with separation and discrimination method, the vegetation construction's contribution to the reduction of runoff and sediment was 92.9% and 94.3% during the evaluation period, respectively. In the watershed of 42 hm2, from 1987 to 1991, a total of 53 thousand Alnus cremastogyne Burk., 37 thousand Cupressus funebris Endl., 31 thousand Morus alba L., 800 Citrus reticulata Blanco, 10 hm2Coriaria nepalensis Wall. and Vitex negundo Linn were planted. Forestland was increased from 9.72 to 20.13 hm2, which made coverage increased by over 1 time. It was seen that vegetation construction has exerted a leading role on the decrement of runoff and sediment. Furthermore, the effect of soil conservation is better than that of water conservation. When reducing the sediment, runoff is also reduced. Therefore, water safety should be taken into account besides controlling soil erosion. A reasonable vegetation construction plan is needed in the future. © 2017, Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering. All right reserved.
Number of references:30
Main heading:Runoff
Controlled terms:Corrosion resistance - Ecology - Environmental management - Erosion - Evapotranspiration - Forestry - Groundwater - Infiltration - Plants (botany) - Rain - Sediments - Soil conservation - Soils - Vegetation - Water conservation - Watersheds
Uncontrolled terms:Citrus reticulata Blanco - Concentrated rainfalls - Double mass - Ecological engineering - Flow duration curve - Purple soils - Rainfall infiltration - Soil and water conservation
Classification code:443.3 Precipitation - 444 Water Resources - 454 Environmental Engineering - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 539.1 Metals Corrosion
Numerical data indexing:Percentage 3.46e+01%, Percentage 6.50e+02%, Percentage 7.63e+01%, Percentage 8.10e+00%, Percentage 8.42e+01%, Percentage 8.99e+01%, Percentage 9.29e+01%, Percentage 9.43e+01%
DOI:10.11975/j.issn.1002-6819.2017.02.019

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