<RECORD 1>

Accession number:20145100353378
Title:Estimation on hole seeding quantity of super hybrid rice based on machine vision and BP neural network
Authors:Tan, Suiyan (1); Ma, Xu (1); Wu, Lulu (1); Li, Zehua (1); Liang, Zhongwei (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou , China; (2) College of Science, South China Agricultural University, Guangzhou , China
Corresponding author:Ma, Xu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:201-208
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Super hybrid rice that is widely cultivated in China is mainly planted by transplanting techniques. In super hybrid rice transplanting, a seedling nursery is a preliminary but critical one. Complete rice seedling nursing operations include seed selection, seed germination, sowing of seeds onto seeded trays, and seedling hardening. The sowing process is performed on an automated seeder sowing test line. Matured seedlings are transplanted to the field by transplanters, which are specially designed for transplanting rice seedlings.
Number of references:23
Main heading:Seed
Controlled terms:Automation - Cells - Computer vision - Cytology - Feature extraction - Grain (agricultural product) - Image processing - Image segmentation - Impurities - Neural networks
Uncontrolled terms:BP neural network classifier - BP neural networks - Classification accuracy - Connected region - Geometric feature - Hybrid rice - Image binarization - Overall accuracies
Classification code:461.1 Biomedical Engineering - 461.2 Biological Materials and Tissue Engineering - 716 Telecommunication; Radar, Radio and Television - 731 Automatic Control Principles and Applications - 731.6 Robot Applications - 732 Control Devices - 741 Light, Optics and Optical Devices - 821.4 Agricultural Products - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.21.024
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 2>

Accession number:20145100353394
Title:Optimization of microwave-assisted enzyme extraction process of polysaccharide from Pleurotus eryngii stalk residue after deep treatment
Authors:Ke, Leqin (1); Zhang, Dongxu (1); Xiao, Jianzhong (1)
Author affiliation:(1) College of Ecology, Lishui University, Lishui , China
Corresponding author:Ke, Leqin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:332-338
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pleurotus eryngii is a kind of valuable edible and medicinal fungus, which contains a lot of effective ingredients. Modern pharmacological researches show that, Pleurotus eryngii fruit body has the function of decreasing blood pressure and reducing blood lipid. Polysaccharides are the main active components of Pleurotus eryngii, which have the antioxidant, antibacterial, antiviral and antitumor effects. The polysaccharide extraction methods include hot-water extraction, ultrasound, microwave, high temperature and high-pressure extraction. At present, the extraction of Pleurotus eryngii polysaccharides is mainly performed by hot-water extraction, which has long extraction time, high energy consumption and low extraction yield. Pleurotus eryngii stalk residue is the byproducts of fruit body processing. It contains rich protein and polysaccharide, and has multiple biological activities and physiological functions, similar with the fruit body. At present, Pleurotus eryngii stalk residue is often used as feed and fertilizer, or directly discarded. The utilization rate of Pleurotus eryngii stalk residue is very low, and it even causes the environment pollution. In 2012, the yield of Pleurotus eryngii in China is about 730 000 tons, and the stalk residue after fruit body processing is about 36 000 tons. Enzymatic treatment is a new technology in food and pharmaceutical industry, which is widely used in extracting biological active substances from animal and plant raw materials, with advantage of high extraction rate, low energy requirement, low cost and simple operation. Microwave assisted extraction is a physical enhancement process of heat and mass transfer, based on traditional extraction process. This method has improved extracting speed, efficiency and quality, compared with conventional extraction process. It has been widely applied to extraction of plant active components. At present, application of enzymatic treatment combined with microwave assisted extraction to extracting polysaccharides from Pleurotus eryngii has not been reported. In this study, the microwave extraction based on enzymatic treatment was used to extract polysaccharides from Pleurotus eryngii stalk residue. The main factors affecting polysaccharide yield (water-material ratio, extraction time and microwave power) were investigated and optimized by response surface design using Design-Expert 7.1.6 software. The enzyme-microwave extraction method was compared with water heating extraction. The antioxidant activities (scavenging capacities on DPPH, hydroxyl free radical and superoxide anion free radical) and antimicrobial activities of Pleurotus eryngii polysaccharides were evaluated. Results showed that, the optimized microwave extraction conditions were as followed: water-material ratio, 35:1 mL/g; extraction time, 15 min, microwave power, 570 W. Under these conditions, the polysaccharide yield was 12.11%&plusmn;1.02%, which was 41.21% higher than that by water heating extraction method, and the extraction time was shortened by 105 min. The Pleurotus eryngii polysaccharides had certain scavenging effect on DPPH, hydroxyl free radical and superoxide anion free radical, with half maximal inhibitory concentration (IC<inf>50</inf>) of 22.9, 19 and 21.1 mg/mL, respectively. In addition, the Pleurotus eryngii polysaccharides had good inhibitory effect on Bacillus subtilis, Escherichia coli and Staphylococcus aureus, with minimum inhibitory concentration of 8, 16 and 16 mg/mL, respectively. They had no obvious inhibitory effect on Aspergillus niger or Saccharomyces cerevisiae. This study has provided a technical basis for further development of Pleurotus eryngii polysaccharide functions and utilization of Pleurotus eryngii stalk residue.
Number of references:22
Main heading:Extraction
Controlled terms:Antioxidants - Aspergillus - Bacteria - Bacteriology - Biological materials - Blood pressure - Byproducts - Energy utilization - Enzymes - Escherichia coli  - Free radicals - Fruits - High temperature operations - Mass transfer - Microwave generation - Microwave power transmission - Microwaves - Oxygen - Plants (botany) - Polysaccharides  - Thermodynamic properties - Water - Yeast
Uncontrolled terms:High energy consumption - High-pressure extraction - Inhibitory concentration - Microwave-assisted extraction - Minimum inhibitory concentration - Pharmacological research - Pleurotus eryngii - Response surface designs
Classification code:444 Water Resources - 461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 525.3 Energy Utilization - 641.1 Thermodynamics - 641.3 Mass Transfer - 706.1.1 Electric Power Transmission - 711 Electromagnetic Waves - 714.2 Semiconductor Devices and Integrated Circuits - 801.2 Biochemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 821.4 Agricultural Products - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2014.21.040
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 3>

Accession number:20145100353360
Title:Joint simulation of radiated noise of electric powertrain based on finite element modeling and boundary element method
Authors:Fang, Yuan (1); Zhang, Tong (1); Yu, Peng (1); Guo, Rong (1)
Author affiliation:(1) New Clean Energy Automotive Engineering Center, Tongji University, Shanghai , China; (2) School of Automotive Studies, Tongji University, Shanghai , China; (3) Sino-German College of Applied Sciences, Tongji University, Shanghai , China
Corresponding author:Zhang, Tong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:40-46
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Evaluation of the NVH (noise, vibration and harshness) performance of automotive powertrain has been an integral part of the vehicle development process. Although electric vehicles are generally considerably quieter than their counterparts powered by internal combustion engines, some problems about NVH still exist, which are becoming more challenging in terms of the future of vehicle. Firstly, the sound only from dominant engine but not from tire, wind or auxiliaries disappears, which consequently becomes increasingly audible due to the removal of the masking sound of broadband engine. Moreover, the interior noise is characterized by high-frequency noise components which can be subjectively perceived as annoying and unpleasant. Thirdly, as the electric vehicle develops toward the direction of high speed and large torque, electric vehicle vibration and noise problems highlight gradually.
Number of references:17
Main heading:Electric machine theory
Controlled terms:Acoustic emissions - Acoustic noise - Acoustic noise measurement - Acoustic radiators - Acoustic wave propagation - Acoustic wave transmission - Acoustic waves - Boundary element method - Combustion - Electric vehicles  - Engines - Finite element method - Gears - Internal combustion engines - Modal analysis - Numerical methods - Powertrains - Radiation - Sailing vessels - Structural dynamics  - Time varying networks - Traction motors - Vibration analysis
Uncontrolled terms:Acoustic radiation - Electric power trains - Electromagnetic radial forces - Noise , vibration and harshness - Numerical simulation method - Radiated sound pressure - Vehicle development process - Vibration modal analysis
Classification code:408 Structural Design - 432 Highway Transportation - 521.1 Fuel Combustion - 601.2 Machine Components - 612 Engines - 663.2 Heavy Duty Motor Vehicle Components - 674.1 Small Marine Craft - 703.1 Electric Networks - 705.1 Electric Machinery, General - 705.3 Electric Motors - 711 Electromagnetic Waves - 751 Acoustics, Noise. Sound - 752.4 Acoustic Generators - 921 Mathematics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.21.006
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 4>

Accession number:20145100353383
Title:Preparation of poly aluminum silicate sulfate flocculant from rice husk ash and its structure performance
Authors:Zhou, Ying (1); Liu, Long (1); Li, Zhe (1); Song, Linna (1); Wu, Wenjie (1)
Author affiliation:(1) College of Materials Science and Chemical Engineering, Tianjin University of Science and Technology, Tianjin , China
Corresponding author:Wu, Wenjie
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:241-248
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rice husk ash was a kind of resource, but it was often wasted. In order to better use rice husk ash, the process of poly-generation of sodium silicate and activated carbon from rice husk ash, and the further production of poly aluminum silicate sulfate (PASS)from sodium silicate were reported in this paper. In addition, the flocculation performance of PASS for the treatment of organic waste water was investigated, and the structure of PASS was also characterized with several different analysis methods. As is well known, the ash-alkali ratio has a significant influence on the modulus of sodium silicate and methylene blue adsorption value of activated carbon in the process of poly-generation of sodium silicate and activated carbon from rice husk. In this paper, the reaction of rice husk ash and sodium hydroxide was carried out in a kettle at a ratio of 10:1.5; after a certain amount of distilled water was added and the temperature heated up to 100, reaction continued for 2 h with constant stirring. When the schedule time was reached, the filtration of the reaction product was conducted, and the sodium silicate with high modulus, namely the filter liquor, was obtained through the filtration, and the residue was treated with alkali for three times with the ash-alkali ratio of 10:3, 10:6, and 10:10, respectively. Then the sodium silicate (the filter liquor) with different modulus (3.3, 2.3, and 1.1) was obtained, and the residue became the activated carbon with adsorption performance through further treatment. Besides, the influence of the concentration of silica, the mole ratio of aluminum to silicon, and pH value on the flocculation performance of PASS, which was prepared with the sodium silicate with the modulus of 3.3, was investigated. In this experiment, the activation of sodium silicate was conducted with the concentration of 3%~8% and pH value of 1.0~4.0 for a period of time, and the solution of aluminum sulfate was added to the sodium silicate at a certain molar ratio of aluminum to silicon. The results showed that the optimal process conditions for preparing PASS were as follows: silica concentration of 7%, aluminum silicon ratio of 1:2, and pH value of 2.0. The PASS was prepared at the optimal conditions mentioned above and used for the treatment of organic waste water. The rates of turbidity and color removal were 97.29 % and 94.26%, respectively, when the dosage of PASS was 60 mg/L (based on Al<inf>2</inf>O<inf>3</inf>). Moreover, the flocculation performance of PASS was better than that of PAC when the same amount of them were poured into the water. Finally, the structure and morphology of PASS was characterized by Fourier transform infrared spectrometer (FTIR), X-ray diffraction (XRD) and scanning electron microscopy (SEM) after drying at 50. The results of FTIR and XRD showed that the PASS was a complex compound of silicon and aluminum instead of a mixture, and the results of SEM showed that the flocculation performance of PASS was affected by the mole ratio of aluminum to silicon to some extent.
Number of references:21
Main heading:Sodium silicate process
Controlled terms:Activated carbon - Activated carbon treatment - Adsorption - Aluminosilicates - Aluminum - Aromatic compounds - Color removal (water treatment) - Flocculation - Fourier transform infrared spectroscopy - Functions  - Infrared drying - Mullite - pH - Scanning electron microscopy - Silica - Silicon - Sodium - Sodium sulfate - Sulfur compounds - Turbidity  - Wastes - Wastewater treatment - X ray diffraction
Uncontrolled terms:Flocculation performance - Fourier transform infrared spectrometer - Methylene blue adsorption - Organic wastewater - Rice husk ash - Structure and morphology - Turbidity removal - Water glass
Classification code:445.1 Water Treatment Techniques - 452.3 Industrial Wastes - 452.4 Industrial Wastes Treatment and Disposal - 482.2 Minerals - 534.2 Foundry Practice - 541.1 Aluminum - 549.1 Alkali Metals - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 741.1 Light/Optics - 801 Chemistry - 801.1 Chemistry, General - 802.3 Chemical Operations - 804 Chemical Products Generally - 921 Mathematics - 931.3 Atomic and Molecular Physics
DOI:10.3969/j.issn.1002-6819.2014.21.029
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 5>

Accession number:20145100353361
Title:Simulation and verification on spray influence of butanol/diesel blends effected by injection pressure and backpressure
Authors:Wu, Jian (1); Hua, Yang (1); Wang, Zhancheng (1); Xu, Bin (1); Zhu, Lili (1)
Author affiliation:(1) Vehicle &amp; Transportation Engineering Institute, Henan University of Science and Technology, Luoyang , China
Corresponding author:Wu, Jian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:47-54
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Butanol is known as a typical second generation biofuel, and it has many advantages as an alternative fuel for engine. At present, the main studies about butanol concentrate on the combustion and emission characteristics. But the research on the spray characteristics is less. The spray atomization of fuel is a key factor that influences the combustion and emission characteristics of diesel engine. So it is important to research the spray characteristics of butanol and diesel blended fuel in depth. First conduct the spray visualization experiment on the spray test bench of high pressure common rail. Then according to the test results, this paper established nozzle flow model and spray model with the aid of AVL Fire software respectively. The nozzle flow and spray are regarded as an unified whole to research the spray characteristics of butanol and diesel fuel mix, and the calculation result of nozzle multiphase flow is used as the initial and boundary conditions for the spray simulation. Then the accuracy of the model is verified by the contrast of spray penetration and spray image. The influence of injection pressure, environment pressure and blending ratio on spray characteristic of n-butanol/diesel blends was studied by the model. And calculate the influence of various factors on the spray form development, spray penetration, SMD, velocity field and concentration field of blended fuel. In this paper, Nn indicates n-butanol and diesel blended fuel with the volume fraction of n-butanol is n. The results show that with the change of injection pressure and environment pressure, the spray form of blended fuel N25 remain unchanged basically. And the differences of spray form mainly displays in the spray penetration and spray cone angle. With the increase of injection pressure, the spray penetration of N25 increases gradually, and sauter mean diameter (SMD) decreases gradually. Then select two points in the velocity field. By comparing the speed of the two points, it can be seen that the speeds of the two points all increase with the increase of injection pressure. This can indicate that the air entrainment enhances with the raise of injection pressure. And the spray center speed and concentration near the axis all increase, with the increase of injection pressure. According to the results of the research on back pressure, with the increase of environment back pressure, the initial velocity of droplet decreases and resistance increases, so the spray penetration of N25 reduces. And SMD is basically unchanged in middle and later of the spray. Because initial velocity of droplet is reduced, which is not beneficial for the droplet broken. Meanwhile with the increase of backpressure, environment density increase, the interaction of environment and fuel enhance, which make the droplet broken quickly. The spray center speed reduces, concentration near the axis increases. According to the results of the research on blending ratio, with the increase of n-butanol blending ratio, the viscosity and surface tension all decrease, then the droplets is easily broken, which leads to the spray penetration and SMD all reduce, and the atomization becomes better. With the increase of environment temperature, the spray penetration of N25 reduces, and SMD significantly decreases after temperature increased by 293.15 K. And then there is a little change with the temperature increasing. In this paper, the spray model is much closer to the actual situation because of coupling the flow inside the nozzle. This paper researches and analyzes the influence of various factors on spray macroscopic and microscopic characteristics of butanol and diesel blended fuel. So this paper could provide a theoretical support for the application of butanol as an alternative fuel for engine.
Number of references:18
Main heading:Spray nozzles
Controlled terms:Air entrainment - Alternative fuels - Atomization - Combustion - Computer simulation - Diesel engines - Diesel fuels - Drops - Engines - Fueling  - Models - Software testing - Spraying - Velocity
Uncontrolled terms:Diesel - Environment pressure - High pressure common rail - Initial and boundary conditions - Injection pressures - Macroscopic and microscopic - N-butanol - Sauter mean diameter (SMD)
Classification code:521.1 Fuel Combustion - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 612 Engines - 612.2 Diesel Engines - 631.1 Fluid Flow, General - 723.5 Computer Applications - 802.3 Chemical Operations - 813.1 Coating Techniques - 902.1 Engineering Graphics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.21.007
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 6>

Accession number:20145100353358
Title:Anti-collision and anti-tipping pre-alarm system of orchard picker based on ZigBee wireless transmission
Authors:Yang, Liu (1); Mu, Haomiao (1); Deng, Junwen (1); Song, Yuyao (1); Liu, Wu (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing , China
Corresponding author:Yang, Liu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:25-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Exploitation of orchard fruit picking locomotive has broad prospects and brings huge economic interests. Meanwhile, China has more complex terrains for orchard distribution, such as plain, hill and terraced hillside, which bring a big security risk for safe and stable driving of orchard locomotive. In order to monitor and prevent tipping, obstacle distance system is particularly important for orchard locomotives in its walking and picking process in the orchard. At present, most pre-alarm system researches are about anti-collision for heavy-duty vehicles or locomotives. There is no system on small vehicles in the orchard, which is working on complex terrain and whose quality is unevenly distributed in the process of moving. This article studies this anti-collision and anti-tipping pre-alarm system of orchard locomotive for further research and improvement. While orchard picker is operating in the orchard, collision and tipping happens easily due to the obstacles and rugged land, which brings danger to the orchard locomotive. In order to give accurate early warning about collision and tipping and ensure to operate orchard picker stably and reliably, this article presents the pre-warning system of anti-rollover collision based on ZigBee wireless transmission. The designed ZigBee wireless network is based on CC2530. The end device collects data from ultrasonic sensor module and spoke type pressure sensors. The design uses a pressure sensor to measure positive pressure between the body and the ground to give rollover warning by comparing with rollover threshold, and uses lateral load transfer ratio (LTR) as an indicator to determine the stability of locomotive tipping. Through the network, the sensor data is sent to the coordinator and then transferred to the computer via RS232 serial port. Alarm is working after the comparison between obtained data and the threshold value. Wireless data transmission test shows that the pre-alarm device realizes the alarm when LTR is 0.9, which prevents tipping effectively; the ultrasonic sensor can detect the obstacles within 2 m, and the error between the measured and real values is not more than 0.01 m, which meets the requirement of anti-collision; the detection data of the pressure sensor conforms to the linear formula 0.3% F&middot;S, which meets the requirement of detection precision of orchard picker wheel pressure. The system uses ZigBee with high reliability, security and low cost, in which wireless transmission mode signals and control signals are detected by the mutual transfer between the sensor and microcontroller to solve the problems such as difficulty and poor scalability of orchard locomotive system wiring, so as to meet the sensor data transmission requirement. The locomotive is a kind of small orchard machinery and the online system is easily installed and with low cost. For the safety in operation of the orchard picker, pre-alarm system for anti-collision and anti- tipping has a significant meaning.
Number of references:24
Main heading:Wireless sensor networks
Controlled terms:Alarm systems - Collision avoidance - Complex networks - Data communication systems - Data transfer - Engines - Locomotives - Orchards - Pressure sensors - Product design  - Signal detection - Ultrasonic applications - Ultrasonic sensors - Vehicles - Wireless networks - Zigbee
Uncontrolled terms:Anticollision - Detection precision - Heavy duty vehicles - Lateral load transfer - Wireless data transmission - Wireless transmissions - ZigBee wireless networks - ZigBee wireless transmission
Classification code:432 Highway Transportation - 612 Engines - 682.1.2 Locomotives - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications - 722 Computer Systems and Equipment - 722.3 Data Communication, Equipment and Techniques - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 753.3 Ultrasonic Applications - 821.3 Agricultural Methods - 913.1 Production Engineering - 914.1 Accidents and Accident Prevention - 914.2 Fires and Fire Protection - 944.3 Pressure Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.21.004
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 7>

Accession number:20145100353359
Title:Research on actual steering power ratio of differential steering mechanism of tracked vehicle on soft ground
Authors:Chi, Yuan (1); Shi, Dandan (1); Wang, Hongtao (1); Zhang, Rongrong (1)
Author affiliation:(1) Engineering College, Northeast Agricultural University, Harbin , China
Corresponding author:Chi, Yuan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:32-39
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Tracked vehicles can steer at any turning radius in small plot adopting differential steering mechanisms. In order to analyze the turning performance of differential steering mechanisms on tracked vehicles, tracked prototype experiments on soft terrain are performed. After analyzing the research results of scholars in the field at home and abroad, we further studied the relationship between steering power ratio and turning radius, skid ratio and steering coefficient. We built the tracked experimental prototype and connected test equipments to it. Dual-power is input into prototypes, rotational speeds, and moments are recorded by hall rotational speed sensors and self-made moment sensors, respectively. The test methods of turning radius, skid ratio, and steering coefficient are introduced. Because the existence of the skid of two tracks, there is a difference between theoretical steering power ratio and experimental steering power ratio. Through analyzing the experimental data, the relationship curve between experimental turning radius and experimental steering power ratio can be derived. Whether being steered differently in small turning radius or in large, experimental steering, power ratio decreases as experimental turning radius increases. In different turning radius, comparison theoretical steering power ratio with experimental steering power ratio is acquired. Through analyzing the diagrams of the relationship between experimental steering power ratio and skid ratio, we know that the skid ratio of the low-speed track is more than that of the high-speed track when experimental prototype steered in small radius. But variation trends between steering power ratio and skid ratio is not obvious. It is difficult to know how the skid ratio affected the steering power ratio. With the steering power ratio increasing, there is also an increasing trend both for the skid ratio of low-speed track and the skid ratio of high-speed track when experimental prototype is steered in big radius. Through the test data, we can also know the relationship between experimental steering power ratio and steering coefficient in different turning radius, and figure out the radial images of them. The analysis shows that the experimental relationship between steering power ratio and steering coefficient is in accordance with theoretical radial relationship between them. The test results also indicate that maximum value of steering power ratio of tracked prototype adopting differential steering mechanism is less than 4. Different degree slippages of the two tracks and different experimental prototypes will lead to a different turning radius. At the same time, steering power ratio has relations to steering coefficient, turning radius, and skid ratio. Due to the different degrees of skid ratio on low-speed and high-speed tracks and different track gauges in experimental steering, the experimental ray and theoretical ray of steering power ratio and steering coefficient are also slightly different. Combining theoretical deduction and quantitative analysis of the relationships between experimental steering power ratio and influencing factors, research results can enrich differential steering theory of tracked vehicles for adopting differential steering mechanism. It will pave the way to further evaluate turning performance of vehicle tracked for adopting differential steering mechanism, and further compare the differential steering with traditional clutch-brake steering.
Number of references:23
Main heading:Steering
Controlled terms:Automobile steering equipment - Soils - Speed - Technology transfer - Testing - Tracked vehicles - Vehicle performance - Vehicles
Uncontrolled terms:Differential steering - Differential steering mechanism - Experimental prototype - Power ratio - Prototype experiment - Slippage - Turning performance - Turning radius
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 432 Highway Transportation - 483.1 Soils and Soil Mechanics - 663 Buses, Tractors and Trucks - 911.2 Industrial Economics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.21.005
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 8>

Accession number:20145100353369
Title:Optimization method of unbiased soil sampling and layout using categorical auxiliary variables information
Authors:Ren, Xuhong (1); Pan, Yuchun (1); Gao, Bingbo (1); Liu, Yu (1)
Author affiliation:(1) National Engineering Research Center for Information Technology in Agriculture, Beijing , China; (2) Key Laboratory for Information Technologies in Agriculture, The Ministry of Agriculture, Beijing , China; (3) College of Computer and Information Technology, China Three Gorges University, Yichang , China; (4) College of Computer and Remote Sensing Information Technology, North China Institute of Aerospace Engineering, Langfang , China
Corresponding author:Pan, Yuchun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:120-128
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The unbiasedness in feature space and geographical space is generally used for evaluating the samples' representation in measure region. Although auxiliary variables are often used for mapping soil variables, problems associated with categorical variables are rarely mentioned. In this paper, a method of unbiased sampling of soil which compromise ing between spreading in geographical space and feature space is presented for optimization of the sample pattern based on multidimensional categorical auxiliary variables. In this method, the feature space is constructed of categorical auxiliary variables; the optimization function which blends the uniform distributions of feature space and geographical space is minimized. The optimal pattern is obtained using simulated annealing. In addition, Feature Divation Index (FDI) is defined in the paper to measure the unbiasedness in feature space of samples. The method was tested through a case study on the soil heavy metal in farmland in Shunyi District, Beijing. As basis data of experiment, the spatial distribution data of samples in the study area were selected in 2007, 2008, 2009 years. The original sample size was 1139, from which the calculated optimal sampling number without considering spatial correlation was 450. Taking 100 as lower limit and 450 as upper limit, eight datasets of sampling number were set, which were 100, 150, 200, 250, 300, 350, 400, 450, respectively. According to scale transformation, the sampling scales were 0.225, 0.239, 0.255, 0.275, 0.302, 0.337, 0.389, 0.477, respectively. Two patterns were selected as the sampling layout to compare with the unbiased sampling: the patterns of uniform sampling in feature space (feature uniform sampling) and of uniform sampling in geographic space (geographical uniform sampling). Land type, soil texture and parent material as categorical auxiliary variables were used to represent the feature space of soil variables. The performances in the overall estimates, the uniformity in feature space and the mapping accuracy were compared between the 3 types of designs. It can be concluded that in the case of global estimation, based on relative error of mean, range, coefficient of skewness and kurtosis, the precision of geographical uniform sampling is worst; when the sampling scale is larger than 0.275, feature uniform sampling achieves best results; as the sampling scale becomes smaller, unbiased sampling can get better results. What's more, the sampling designs by geographical uniform sampling have the worst feature presentation. When the sampling scale is larger, the representative of samples by feature uniform sampling in feature space is the best; when sampling scale is less than 0.302, unbiased sampling is suggested as a prudent sampling strategy. Finally, in the case of forming geostatistical map, root mean square error (RMSE) between basis data and the Kriging predicted data is used. Unbiased sampling is shown to be competitive in reproducing area with high accuracy. In a word, among the methods of optimizing sampling based on auxiliary variable, the feature uniform sampling is suitable in the situation of large sampling scale or fewer sample points and can only be used in global estimation; the unbiased sampling is a good compromise between spreading in geographical space and feature space, and it can achieve better result in the case of small sampling scale or more sample points.
Number of references:28
Main heading:Soils
Controlled terms:Heavy metals - Higher order statistics - Mapping - Mean square error - Optimization - Sampling - Simulated annealing
Uncontrolled terms:Auxiliary variables - Feature space - Geostatistical - Global estimation - Unbiased samplings
Classification code:483.1 Soils and Soil Mechanics - 531 Metallurgy and Metallography - 801 Chemistry - 902.1 Engineering Graphics - 921 Mathematics - 921.5 Optimization Techniques - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.21.015
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 9>

Accession number:20145100353386
Title:Change of cultivated land and its impact on grain production pattern in Huang-Huai-Hai Plain
Authors:Hong, Shuman (1); Hao, Jinmin (1); Zhou, Ning (1); Chen, Li (1); L, Zhenyu (1)
Author affiliation:(1) College of Resources Environmental Sciences, China Agricultural University, Beijing , China
Corresponding author:Hao, Jinmin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:268-277
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the rapid development of urbanization and industrialization, the conflicts of decreased cultivated land areas and increased grain needs are significant in China. Based on per capita, cultivated land area of China is less than the world average's 1/2 and the quality of land in China is generally poor, changes of the quantity and quality of cultivated land have a significant impact on the national food security. It's an important basis for region's food security by analyzing the changing characteristics of quantity and quality of cultivated land and its effect on change of grain production patterns in the region. Huang-Huai-Hai plain is the main grain production area of China, its grain production level has always been in the forefront in the nine comprehensive agricultural areas of China. The research about grain production of Huang-Huai-Hai plain in the last 30 years has shown that the increase of grain production mainly depends on the grain yield increase. Because the increase in grain yield of Huang-Huai-Hai plain has been more difficult in recent years, it is important to analyze the change of the characteristics of quantity and quality of cultivated land, and the effect of such change on grain production patterns. In this study based on Huang-Huai-Hai plain, we analyzed temporal and spatial variation of the quantity and quality of cultivated land and its effect on change of grain production pattern by using the change intensity of cultivated land model, the spatial variation index model, the spatial transferring of grain production model, the grain sown area model, and the grain production model. The results showed that the quantity of cultivated land in Huang-Huai-Hai plain changed with a net decrease of 384 900 hm² from 2000-2008. There were two corridors of cultivated land with a sharp reduction, one was Beijing-Baoding-Shijiazhuang-Handan-Xinxiang-Zhengzhou, the other was Tianjin-Cangzhou-Jinan-Jining-Xuzhou-Lianyungang. Due to the decrease of cultivated land quantity in Huang-Huai-Hai plain from 2000-2008, the grain sown area changed with a net decrease of 464 500 hm². Due to the decrease of cultivated land quality in Huang-Huai-Hai plain from 2000-2008, the grain production changed with a net decrease of 2 703 700 t. There were three types in spatial transferring of grain production. The region of transferring-out located in the west and north of Hai-He plain, and in the northeast and northwest of Huang-Huai plain. Its capability of grain production was decreased due to the decrease of grain sown area, the decrease of high-yield and medium yield cultivated land, and the increase of low yield cultivated land. The region of transferring-in located in the east and southeast of Hai-He plain, and in the east and south of Huang-Huai plain. Its capability of grain production was increased owe to the increase of grain sown area and the increase of high-yield cultivated land. The stable region located in the southwest of Hai-He plain and the north of Huang-Huai plain. Its capability of grain production was stable. In future, the irrigation facilities in Huang-Huai-Hai plain should be improved and the patterns of multiple cropping should be extended to promote the grain production of region. In all, the high-yield cultivated land should be constructed to promote the efficient of cultivated land use. In addition, the compensation mechanism of long-term interests for buildings in arable land is important for protecting arable land for food supply capacity of Huang-Huai-Hai plain.
Number of references:26
Main heading:Landforms
Controlled terms:Agriculture - Classification (of information) - Food products - Food supply - Grain (agricultural product) - Land use
Uncontrolled terms:Compensation mechanism - Cultivated land qualities - Cultivated lands - Grain production levels - Huang-Huai-Hai Plain - Long-term interests - Spatial variations - Temporal and spatial variation
Classification code:403 Urban and Regional Planning and Development - 481.1 Geology - 716.1 Information Theory and Signal Processing - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.4 Agricultural Products - 822.3 Food Products
DOI:10.3969/j.issn.1002-6819.2014.21.032
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 10>

Accession number:20145100353372
Title:Risk evaluation of Chengdu's flood hazard based on evidence theory and variable fuzzy sets theory
Authors:Ren, Yufeng (1); Liu, Guodong (1); Zhou, Li (1); Zhang, Chunmin (1)
Author affiliation:(1) College of Water Resource &amp; Hydropower, Sichuan University, Chengdu , China; (2) State Key Laboratory of Hydraulics and Mountain River Engineering,, Sichuan University, Chengdu , China
Corresponding author:Liu, Guodong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:147-156
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Under the background of global climate change, the sustainable development of a society is extraordinarily endangered by the growing frequent and severe flood in China. Flood hazard is a highly uncertain and high-dimensional system. Thus, more difficulties emerge when carrying out flood risk evaluation. In this paper, the Dempster-Shafer (DS) evidence theory was applied to evaluate the flood hazard risk due to its ability in multisource information fusing and information uncertainty processing. The establishment of basic belief assignment (BBA) called evidence model is the nodus and hotspot in DS evidence theory research. In order to solve this problem, BBA was established and combined with comprehensive relative membership degree of index by using variable fuzzy sets theory (VFS). More specifically, the value of BBA was assigned by relatively comprehensive membership degree of VFS theory during the calculation process. BBA of hazard-formative environment, disaster-inducing factors and hazard bearing body were seen as the three pieces of evidence, and these evidences were combined by the classical evidence combination principle. Then, the decisions of flood disaster risk assessment were made by comparing quality function, belief function, relief function and uncertainty of each risk degree. So far, the objective and reasonable evidence model was established in this way while the conflict evidence was greatly reduced. Through evidence combination and the calculation of confidence, likelihood and uncertain interval of different risk degrees based on the classic evidence combination principle, the flood hazard risk was accurately assessed. The DS_VFS model was applied to evaluate the flood hazard risk in Cheng Du where flood disaster has been serious since ancient times. The study area was divided into 12 partitions and each subarea's hazard risk degree was calculated respectively by using DS_VFS model. The results indicated that the risk degree of Cheng Du was high, especially in the northwest, northeast and southwest. According to the spatial and time analysis, the risk growth was mainly due to three factors, increase in population, lagging infrastructure in economic development and continuous deterioration of the natural environment. In order to verify the DS-VFS model, the same historical flood data, altitude and slope data, rainfall data series and socioeconomic data were used in VFS theory, and the result was compared with the flood risk degrees calculated by DS-VFS. The comparison showed that the results of the DS_VFS model were more accurate and accorded better with the actual situation than the VFS results. The multidimensional information of social, economic and natural environment was fused, and uncertain interval of different degrees was calculated. Moreover, the purpose of accurate assessment of flood disaster risk in the study area was achieved by using the DS_VFS model, which was developed from the traditional fuzzy model. However, there were some problems that remain unaddressed in the current study. The conflict evidence was greatly reduced by calculating relative-membership grades, but it was not totally avoided. Besides, wrong decisions can be produced based on the classic evidence combination principle where the conflict evidence was high. In addition, many other calculation methods and decision fusion theories are available to be introduced into the DS_VFS model in the future research, such as support vector machine, absorption method, evidence distance function based on confidence, etc.
Number of references:33
Main heading:Floods
Controlled terms:Algorithms - Climate change - Damage detection - Disasters - Economics - Flood damage - Function evaluation - Fuzzy set theory - Fuzzy sets - Hazards  - Population statistics - Risk assessment - Sustainable development - Uncertainty analysis
Uncontrolled terms:Dempster Shafer evidence theory - High-dimensional systems - Multi-source informations - Multidimensional information - Relative membership degrees - Uncertainty - Variable fuzzy set - Variable fuzzy sets theories
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 451 Air Pollution - 911.2 Industrial Economics - 914.1 Accidents and Accident Prevention - 921 Mathematics - 922.1 Probability Theory - 922.2 Mathematical Statistics - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.21.018
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 11>

Accession number:20145100353368
Title:Natural restoration improves soil's water-storage function in abandoned dryland of purple hilly region
Authors:Liao, Chaolin (1); Fu, Lingyi (1); Sheng, Hao (1); Yuan, Hong (1); Zhou, Qing (1); Huang, Yunxiang (1); Zhang, Yangzhu (1)
Author affiliation:(1) College of Resources and Environment, Hunan Agricultural University, Changsha , China
Corresponding author:Liao, Chaolin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:111-119
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The restoration of vegetation in the abandoned land requires support of water resources, but as drought events occur frequently in Southern China, especially significant in purple hilly region of central Hunan the restoration is often difficult. As a result, the vegetation is rare in purple hilly region and the eco-environment is very fragile, and soil degradation and erosion are very severely. Since 1990s, more and more dry-land in the hilly region was abandoned by the farmers because of the enlarging gap between the prices of farm products and manufactured products. After dry-land was abandoned, the pioneer plants inhabit first and vegetation succession begin, which affect soil characteristics, microbiology and microclimate. Conversely, the soils in the region also affect the type, distribution and dynamic change of vegetation through providing water and mineral nutrients. Earlier studies reveal that vegetation restoration improves soil structure, increase proportion of soil porosity, and soil water storage capacity for vegetation succession. Vegetation restoration is one of the primary measures to improve eco-environment of the purple hilly region. Our objective was to determine the impact of natural vegetation restoration in abandoned dry-land and the impact of succession stages on soil physical properties and soil water characteristics. In this paper, four natural lands with various succession stages on abandoned dry land from the purple hilly region were selected to study soil water storage capacity and related soil physical properties by using "adjacent plot comparing method". The results showed that: no obvious changes occurred in subsoil (20-40 cm) bulk density among different succession stages (P&gt;0.05). However, there was notable changes in surface soil layer (0-20 cm), the order of the average values was as follows: dryland &gt; herbosa &gt; arbor-shrub community &gt;shrub community, and the value of soil bulk density was 1.38 g/cm³, 1.3 g/cm³, 1.24 g/cm³ and 1.19 g/cm³, respectively, indicating that vegetation restoration incurred lower bulk density of surface soil. The results also showed that the quality distribution of soil particle varied obviously (P&lt;0.05). The content of gravel (1-2 mm) and coarse sand (0.25-1 mm) in herbosa was higher comparing with dry land. The content of gravel and coarse sand decreased and that of silty clay (&lt;0.05 mm) and fine sand (0.05-0.25 mm) increased in stage of arbor-shrub and shrub community. In the same soil layer for different succession stages, there was higher proportion (P&lt;0.05) of finer soil particle content in arbor-shrub and shrub community, however, soil particle content in vertical structure of profile varied obviously in succession middle stage and it was uniform in arbor-shrub stage. In addition, the results showed that the soil capillary porosity of surface soil in herbosa stage was significantly lower (P&lt;0.05) than the other types of vegetation, indicating vegetation succession on abandoned dry land can increase soil capillary porosity. Non-capillary porosity varied indistinctively in different succession stages. All soil total porosity of surface soil was higher than subsoil at different succession stages and there was significant level (P&lt;0.05) in herbosa stage, showing that vegetation succession affected soil total porosity. Moreover, the results showed that soil water-storage capacity had the same changing pattern with soil porosity in different succession stages. Soil capillary and total water-storage capacity of topsoil with various succession stages increased (P&lt;0.05), which showed that vegetation restoration might raise soil water storage capacity. Last, correlation analysis of various soil physical properties indicated that soil water storage capacity mainly determined by soil bulk density, porosity, coarse sand (0.25-1 mm) and silt and clay (&lt;0.05 mm) content. We concluded that vegetation succession stages altered soil surface physical properties greater than the subsurface soil. The decrease in bulk density and increase in porosity helped to improve soil water holding capacity and hence improved the environment for vegetation establishment.
Number of references:26
Main heading:Vegetation
Controlled terms:Ecology - Forestry - Gravel - Physical properties - Porosity - Restoration - Sand - Soil moisture - Soils - Water resources
Uncontrolled terms:Dryland - Hilly region - Natural vegetation - Soil water characteristics - Storage function - Vegetation establishments - Vegetation restoration - Vegetation successions
Classification code:402 Buildings and Towers - 409 Civil Engineering, General - 444 Water Resources - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 483.2 Foundations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2014.21.014
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 12>

Accession number:20145100353391
Title:Impact test and analysis of fracture toughness of ramie stalk
Authors:Yan, Keman (1); Zou, Shuchang (1); Tang, Lingbo (1); Su, Gongbing (1)
Author affiliation:(1) Mechanical and Automation College, Wuhan Textile University, Wuhan , China
Corresponding author:Su, Gongbing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:308-315
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Ramie is a perennial crop and is normally harvested three times a year. The mechanical and physical properties of ramie differ from each period due to the different growth climate and environment. The first period of ramie was abundant from late May to early June, the second period was abundant in early August, and the third period of ramie was abundant in late October. It was discovered that the separation of ramie stalk has a lot to do with the time of harvesting, storage, stripping, and moisture content. The ramie stems of the second harvest were struck and used as the objects of study. Impact tests of the ramie stems of the second harvest were carried out to discover the distribution law of fracture energy and to design the mechanical peeling parameters of ramie harvest and store. According to the standard of GB/T 1843-2008 with a TF-2056B Izod impact testing machine, the ramie stems varying in moisture percentage were struck in different parts. Tests of ramie stalk impact fracture energy under different conditions of moisture content were carried out to investigate the biggest impact fracture energy, and the result can provide a theoretical basis and main technical parameters for the determination of time for harvesting, storage, stripping, and mechanism design for low energy consumption with high efficiency separation.
Number of references:15
Main heading:Fracture
Controlled terms:Bars (metal) - Energy utilization - Fracture energy - Fracture toughness - Harvesting - Hemp - Impact testing - Machine design - Moisture - Moisture determination  - Separation - Toughness - Water content
Uncontrolled terms:Cylindrical specimens - Impact fracture energy - Low energy consumption - Main technical parameters - Mechanical and physical properties - Mechanical peeling - Ramie stalks - Test and analysis
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 422.2 Strength of Building Materials : Test Methods - 444 Water Resources - 525.3 Energy Utilization - 535.1.2 Rolling Mill Practice - 601 Mechanical Design - 801.4 Physical Chemistry - 802.3 Chemical Operations - 821.3 Agricultural Methods - 821.4 Agricultural Products - 944.2 Moisture Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.21.037
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 13>

Accession number:20145100353390
Title:Application of hyperspectral imaging technology for detecting adulterate rice
Authors:Sun, Jun (1); Jin, Xiaming (1); Mao, Hanping (2); Wu, Xiaohong (1); Yang, Ning (1)
Author affiliation:(1) School of Electrical and Information Engineering, Jiangsu University, Zhenjiang , China; (2) Jiangsu Provincial Key Laboratory of Modern Agricultural Equipment and Technology, Jiangsu University, Zhenjiang , China
Corresponding author:Sun, Jun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:301-307
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rice is an important food ration of Chinese people, which contains a great number of starch, protein, fat and some nutrient elements. However, rice adulteration is becoming one of the most urgent problems and it needs to be solved as soon as possible in Chinese rice market. Therefore, the purpose of this study was to develop a rapid, precise and nondestructive method to detect the rice adulteration. In this paper, some expensive rice with high quality (Chang-Li-Xiang) and some cheap rice with relatively low quality (Li-Shui) were purchased from the local Wal-Mart in Zhenjiang province, China. Then they were mixed together in five different proportions (0:4, 1:3, 2:2, 3:1 and 4:0) by using electronic scale and the sample of rice adulteration were obtained. The visible and near infrared (VIS-NIR) hyperpectral imaging system with the spectral range of 390-1050 nm was used to capture the hyperspectral images of 200 rice samples. ENVI software was adopted to determine the region of interest (ROI) in the hyperspectral image and extract the hyperspectral data by averaging the reflectance from all the pixels in the ROI images. Then the discriminative model for rice adulteration was established by using support vector machine (SVM) and the extracted hyperspectral data in the full spectral range. The performance of the SVM model was evaluated by using the indexes of cross validation accuracy and prediction accuracy. Finally, the cross validation accuracy was 93% and the prediction accuracy was 98% in the full-spectral-SVM. As there were a large number of noise and redundant information in the raw hyperspectral images and hyperspectral data, some data processing methods should be used to remove the noise, accelerate the processing efficiency and improve the performance of the models. In this paper, the traditional principal component analysis (PCA) method was respectively used to process the hyperspectral images and hyperspectral data from the two aspects of feature selection and feature extraction. For the aspect of feature selection, a total of six characteristic wavelengths (531.1, 702.7, 714.3, 724.7, 888.2 and 930.6 nm) were picked up according to the weight coefficient distribution curve of the first four principal component images under the full wavelengths. For the aspect of feature extraction, the optimal number of principal component (PCs) was determined as 9 by using the leave-one-out cross-validation (LOOCV). Finally, the two kinds of simplified SVM models were respectively developed by using the input data at the six characteristic wavelengths and at the optimal PCs. The experiment results showed that the cross validation and prediction accuracy in the model based on characteristic wavelengths were 95% and 96%, the cross validation and prediction accuracy in the model based on optimal PCs were 94% and 98%. It indicated that the two kinds of simplified models all achieved the promising results and they all had the comparable discriminant power for rice adulteration when compared with the full-spectral-SVM. The results demonstrated that it is feasible to use hyperspectral imaging technology for the detection of the problem of rice adulteration.
Number of references:18
Main heading:Principal component analysis
Controlled terms:Data handling - Electronic scales - Extraction - Feature extraction - Forecasting - Image acquisition - Image segmentation - Imaging techniques - Independent component analysis - Infrared devices  - Lithium - Nondestructive examination - Spectroscopy - Support vector machines
Uncontrolled terms:Data processing methods - Hyperspectral Imaging - Hyperspectral imaging technologies - Leave-one-out cross-validation (LOOCV) - Nondestructive methods - Rice adulteration - The region of interest (ROI) - Visible and near infrared
Classification code:421 Strength of Building Materials; Mechanical Properties - 549.1 Alkali Metals - 715 Electronic Equipment, General Purpose and Industrial - 716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 741.3 Optical Devices and Systems - 801 Chemistry - 802.3 Chemical Operations - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.21.036
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 14>

Accession number:20145100353384
Title:Spatio-temporal modeling and prediction of soil heavy metal based on spatio-temporal Kriging
Authors:Yang, Yong (1); Mei, Yang (1); Zhang, Chutian (1); Zhang, Ruoxi (1); Liao, Xiangsen (1)
Author affiliation:(1) College of Resources and Environment, Huazhong Agricultural University, Wuhan , China
Corresponding author:Yang, Yong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:249-255
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Soil plays a very important role in the food chain, and hence is a very important pathway through which humans come into contact with most pollutants. Therefore, there is considerable interest in the best way to monitor the quality of the soil to ensure that it is managed sustainably. However, when the need to monitor the status of soil heavy metals for one area continuously occurs, the sampling and analysis procedures are expensive and time-consuming. Therefore, space-time interpolation is necessary because we can use previous soil sampling points to predict present spatial distribution with fewer soil samples. In this paper, spatio-temporal kriging was utilized to model and predict the spatio-temporal distribution of soil heavy metals. The main objectives of this study were 1) to explore the methods of obtaining an experimental spatio-temporal semivariogram; 2) to fit models for experimental spatio-temporal semivariogram; 3) to perform the algorithm of spatio-temporal kriging interpolation; 4) to evaluate the accuracy and uncertainty of spatio-temporal kriging under the conditions of different neighborhoods; and 5) to predict the spatio-temporal distribution of soil heavy metals of a study area using spatio-temporal kriging. The study area was east of Qingshan district, Wuhan city, Hubei province, China. To monitor the degree of soil contamination, we collected topsoil samples from the study area every year from 2011 to 2014. The number of soil samples from 2011, 2012, 2013, and 2014 were 45, 48, 55, and 48, respectively. The concentrations of cadmium (Cd), copper (Cu), lead (Pb), and zinc (Zn) were analyzed and used as experimental data. For Cd, Cu, and Zn, soil concentrations showed a constant increase from 2010 to 2014. However, the concentrations of Pb showed an increase from 2010 to 2013, followed by a small decrease in 2014. The results of K-S tests showed that Cd, Pb, and Cu did not follow a normal distribution, however, Zn followed a normal distribution. Therefore, the data of Cd, Pb, and Cu were transformed to their common logarithms to achieve a normal distribution. As the results of experimental spatio-temporal semivariance, the T parts of semivariograms for LogCd, LogCu, and LogPb were modeled with a linear model, for Zn was modeled with an exponential model; The S and ST parts of semivariograms for LogCd, LogCu, LogPb, and Zn were modeled with a spherical model. The method of fitting models was the genetic algorithm proposed by the author in 2011. With the results of theoretical variation semivariogram models of LogCd, LogCu, LogPb, and Zn, spatio-temporal kriging were performed. To determine the influence created by the number of neighborhoods, we decided to predict the unmeasured ST point using 4 to 20 of the nearest ST sampling points around the predicted ST site. The results showed that including more neighborhoods could result in less prediction variance. However, more neighborhoods might not produce less RMSE. In addition, ordinary kriging was performed using the same year sampling points while generating a spatial distribution for one year. The results of comparison RMSE generated by ordinary kriging and spatio-temporal kriging showed that spatio-temporal kriging can produce higher prediction accuracy than ordinary kriging. The results of spatio-temporal distribution generally reveal a tendency of Cd, Cu, and Zn concentrations to spread from the south-western part to the whole study area over time, while Pb contamination tends to concentrate mostly on the northern and western parts. The paper showed the computational process of spatio-temporal kriging and its application to soil heavy metals. The results showed that spatio-temporal kriging can improve the prediction accuracy with the help of multi - temporal data.
Number of references:21
Main heading:Soil pollution
Controlled terms:Forecasting - Genetic algorithms - Heavy metals - Interpolation - Lead - Metals - Monitoring - Normal distribution - Soil surveys - Soils  - Spatial distribution - Zinc
Uncontrolled terms:Computational process - Kriging - Kriging interpolation - Multi-temporal data - Semivariograms - Spatio-temporal models - Spatio-temporal prediction - Spatiotemporal distributions
Classification code:483.1 Soils and Soil Mechanics - 531 Metallurgy and Metallography - 546.1 Lead and Alloys - 546.3 Zinc and Alloys - 723 Computer Software, Data Handling and Applications - 921 Mathematics - 921.6 Numerical Methods - 922.1 Probability Theory - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.21.030
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 15>

Accession number:20145100353393
Title:Subcritical fluid extraction of oil from cold press linseed cake
Authors:Wan, Chuyun (1); Huang, Fenghong (1); Zhang, Ming (1); Li, Wenlin (1); Huang, Qingde (1)
Author affiliation:(1) Oil Crops Research Institute, Chinese Academy of Agricultural Sciences, Wuhan , China; (2) Hubei Key Laboratory of Lipid Chemistry and Nutrition, Wuhan , China
Corresponding author:Huang, Fenghong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:324-331
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Linseed (Linum usitassimum L.), also known as Flaxseed, belonging to family Lineaceae, is an annual herb that is one of the oldest cultivated crops, continues to be widely grown for oil, textile, and food. Currently, Linseed is cultivated in more than 50 countries, predominantly in the Northern hemisphere. The important Linseed growing countries include Canada, China, India, Argentina, and United States. In China, Linseed, as one of five most important kinds of oil crops, of the average production is 500 thousand tons per year. Linseed oil is an excellent source of the omega-3 fatty acid alpha linolenic acid (ALA) with typical levels of 55% in the oil making it ideal for function food and nutritional supplements because they have shown beneficial physiological effects. However, the high content of ALA in flaxseed oil is highly susceptible to oxidation, leading to rapid deterioration of quality. Because ALA is sensitive to heat, oxygen, and light, Linseed is usually cold pressed. Cold presses typically recover 80 to 90% of the oil from oilseeds. To exhaust extract the oil of linseed, a solvent extraction has to be used. However, solvent extraction with petroleum distillates, such as hexane, is not allowed, due to its high temperature process. In order to obtain high quality linseed oil from cold press linseed cake, subcritical butane is used to extract linseed oil and then the quality of the oil and meal obtained is studied, compared with n-hexane extraction. The affection of factors, which includes extraction temperature, time and ratio of solvent to material effecting on oil yield, is investigated, and the extraction parameters are optimized by D-optimum response surface methodology. The model equation for predicting the optimum response values is established by Design Expert software. The adequacy of the model equation for predicting the optimum response values was effectively verified by the validation. The experiment result indicates that affection of ratio of solvent to material and extraction time on oil yield are more significant than extraction temperature. The interaction between extraction temperature and ratio of solvent to material has a significant affection on oil yield. The optimum operation parameters of subcritical butane extraction are: extraction temperature 26,ratio of solvent to material 8.4 mL/g, and extraction time 40 min. In this optimal condition, the oil yield is 96.50% and is similar to the 96.82% predicted as maximum oil yield by the mathematical model under the condition of temperature 25.77 and ratio of solvent to material 8.36 mL/g with extraction time 40 min. The subcritical butane extraction of linseed oil from cold press linseed cake has a nice color and better acid and peroxide value compared to n-hexane extraction. The phospholipid content of oil extracted with subcritical butane is 0.67 mg/g, which is about 1/10 of the n-hexane extraction, and the vitamin E content are 43.78 mg/100 g, which is a little larger than the n-hexane extraction process. The linseed meal obtained from cold press linseed cake with subcritical butane extraction, which has a superior quality compared to the meal obtained by n-hexane extraction, has lower content of neutral detergent fiber and high protein solubility. These experimental results offer a good reference value for high quality processing and utilization of linseed.
Number of references:40
Main heading:Solvent extraction
Controlled terms:Butane - Crops - Cultivation - Drying oils - Extraction - Fatty acids - Flax - Hexane - Image quality - Mathematical models  - Oil shale - Oils and fats - Oilseeds - Optimization - Petroleum distillates - Phospholipids - Presses (machine tools) - Solvents
Uncontrolled terms:Cake and meal - Extraction temperatures - High temperature process - Linseed - Neutral detergent fiber - Nutritional supplements - Oil and fats - Response surface methodology
Classification code:512.1 Petroleum Deposits - 603.1 Machine Tools, General - 741 Light, Optics and Optical Devices - 802.3 Chemical Operations - 804.1 Organic Compounds - 813.2 Coating Materials - 819.1 Natural Fibers - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.21.039
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 16>

Accession number:20145100353379
Title:Method of removing pits of canopy height model from airborne laser radar
Authors:Duan, Zhugeng (1); Zeng, Yuan (2); Zhao, Dan (2); Wu, Bingfang (1); Zhao, Yujin (2); Zhu, Jianjun (1)
Author affiliation:(1) School of GeoSciences and Info-Physics, Central South University, Changsha , China; (2) Key Laboratory of Digital Earth Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing , China; (3) School of Sciences, Central South University of Forestry and Technology, Changsha , China
Corresponding author:Wu, Bingfang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:209-217
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The airborne light detection and ranging (LiDAR) has already been widely used in forest inventory investigation with the advantage of obtaining multiple forest information. The canopy height model (CHM) derived from LiDAR data is a key model, which is used frequently to retrieve forest parameters, such as the tree height, crown width, diameter at breast height, crown density, volume and biomass and so on. However, there exist some abnormal or sudden pits in CHMs, which will have an influence on forest parameters extraction. A method of removing pits from LiDAR-derived CHMs with fusion of the CHMs of the first return point cloud by inverse distance weighted (IDW) interpolation, which is layered according to different thresholds of canopy height, is proposed in the article. In general, the search radius of IDW interpolation is usually set to 1-1.5 times of the original points cloud interval. Three plots are chosen as the experimental data, which respectively represent the needle leaf forest, broadleaf forest, mixed needleleaf and broadleaf forest. Mean pixel values of difference image between CHM and CHM<inf>0</inf> is 3.31, 4.20, 5.88 m respectively in the three plots, which illustrate that the pits are close to the upper canopy, and mainly generated by the first echo point coming from the foliage inside canopy of tree. Maximum pixel values in the difference images were 12.97, 14.99, 29.00 m respectively, which is very close to the measured maximum tree height and maximum height of the normalized point cloud. This indicates that a small amount of CHM pits are generated by the first echo points close to the ground. In other words, the first echo generated CHM pits probably roots in shrubs, low saplings and bare land. Comparative analysis with the profile of CHM<inf>0</inf>, CHM and the original points cloud was performed. CHM removed pits tallies exactly with the original point cloud, which shows that the algorithm developed in this paper changes very little on height of canopy cloud, and keeps the surface structure shape of the original canopy, and loses very little information of canopy. At the same time, we have carried out the experiments that remove pits from LiDAR-derived CHMs when the point clouds in the plots were thinned. And then the result was compared with the smoothing filter algorithm. By comparison,the results show that the proposed algorithm can effectively remove pits of CHM and reserve forest canopy border clearly and canopy gaps. The CHM can accurately express the forest canopy shape, and the proposed algorithm is suitable for different forest types, with the adaptability to point cloud density. The effect of removing pits is better than the smoothing filter algorithms such as the median filtering, Mean filtering and Gaussian filtering. The pit-free and optimized CHM contributes to the subsequent extraction of forest parameters. However, due to the IDW interpolation searching along any direction with a certain radius range, there exists a certain degree of smoothing in canopy, and the small forest gaps are slightly filled, and the height of forest gaps slightly increased, and the crown edge is slightly dilated.
Number of references:30
Main heading:Forestry
Controlled terms:Algorithms - Extraction - Interpolation - Median filters - Models - Optical radar - Pixels - Vegetation
Uncontrolled terms:Airborne laser radar - Canopy Height Models - Comparative analysis - Diameter-at-breast heights - Inverse distance weighted - Light detection and ranging - Pit - Telemeterring
Classification code:703.2 Electric Filters - 716.2 Radar Systems and Equipment - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 902.1 Engineering Graphics - 921 Mathematics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.21.025
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 17>

Accession number:20145100353381
Title:Operation parameter optimization of dry fermentation equipment with garage style based on flexible roof membrane
Authors:Zhu, Dewen (1); Wu, Aibing (1); Wang, Pengjun (1); Tao, Sanqi (1); Qu, Haoli (1); Ma, Biao (1)
Author affiliation:(1) Nanjing Research Institute for Agricultural Mechanization, Ministry of Agriculture, Nanjing , China
Corresponding author:Zhu, Dewen
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:226-233
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China produces the biggest amount of agricultural solid waste in the world. The annual production of agricultural solid waste is approximately 40 billion tons, of which 30 billion tons is livestock and poultry manure, 7 billion tons is crop straw, 1.5 billion tons is vegetable waste, and 2.5 billion tons is garbage and human waste. The waste is not only valuable resources, but also a major source of pollution if it has been discharged into environment without proper treatment. Nowadays as the fossil energy has been gradually dried up, the large-scale application of dry fermentation biogas technology is one of the solution to energy shortage, environmental pollution and the demand for more effective disposal of crop straw, livestock manure and garbages. The research of dry fermentation biogas technology has become a popular project in China. Bigger water demand in wet fermentation process, higher cost in biogas slurry processing, single fermentation material, low fermentation density, and low unit volume gas production are the disadvantage of traditional fermentation method. To solve these problems, this paper suggested a dry fermentation process, and the dry fermentation technology optimization condition were studied. The experiment of anaerobic dry fermentation using the garage style with flexible roof membrane was tried with setting mixture of straw and cattle manure as raw materials. The methane production and material degradation rate using different material ratio, fermentation temperature, biogas slurry spraying times, fermentation time were investigated. Working process was optimized by L<inf>9</inf>(3⁴) orthogonal experimental design. Compared with wet fermentation, the experimental results showed that the optimal working process parameters of the device were material ratio 4:1, fermentation temperature 35, biogas slurry spraying times two times per day, fermentation time 35 days. The volume fraction of CH<inf>4</inf> was 65%, the volumetric gas production rate was 0.63m³/(m³&middot;d) and the material degradation rate reached 45% under the optimum condition. This results were better than those using wet fermentation methods. The insufficiency of the wet fermentation technology could be overcome by dry fermentation technology, which provide the reference for the scale anaerobic dry fermentation production.
Number of references:28
Main heading:Fermentation
Controlled terms:Anaerobic digestion - Biogas - Crops - Degradation - Environmental technology - Garages (parking) - Manures - Methane - Optimization - Pollution  - Process control - Roofs - Solid wastes
Uncontrolled terms:Dry fermentation - Environmental pollutions - Fermentation technologies - Fermentation temperature - Large-scale applications - Orthogonal experimental design - Roof membranes - Working parameters
Classification code:402 Buildings and Towers - 402.2 Public Buildings - 454 Environmental Engineering - 454.2 Environmental Impact and Protection - 522 Gas Fuels - 731 Automatic Control Principles and Applications - 802.2 Chemical Reactions - 811 Cellulose, Paper and Wood Products - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.21.027
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 18>

Accession number:20145100353363
Title:Numerical simulation and test on impeller wear of slurry pump
Authors:Tao, Yi (1); Yuan, Shouqi (1); Zhang, Jinfeng (1); Zhang, Fan (1); Tao, Jianping (3)
Author affiliation:(1) Research Center of Fluid Machinery and Technology, Jiangsu University, Zhenjiang , China; (2) National Research Center of Pumps, Zhenjiang , China; (3) Jiangsu Province Yixing Taoye Nonmetallic Chemical Machinery Factory Co, Ltd., Wuxi , China
Corresponding author:Yuan, Shouqi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:63-69
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The centrifugal slurry pump is a device that is used to deliver high density fluid containing suspended solid. It is generally used in electricity, mining, metallurgy, transportation, water conservancy and environmental protection industry. In order to study wear characteristics of impellers during slurry pump working, a centrifugal engineering plastic slurry pump was chosen as the main study model. The entire solid-liquid two-phase flow field in the model pump, which includes inlet, impeller, volute, back blade passage, and gap was meshed by structured girds with ICEM CFD software. Firstly, single-phase flow fields under five working conditions, including the design working condition, were simulated with the SST k-&omega; turbulence model, and the simulative external characteristic curves were compared with test results. It was found that the maximum error is less than 5%, and the error at the design working condition is less than 3%. It showed that the results of simulation are reliable. Based on the results achieved, mentioned above, particle multiphase model in ANSYS CFX software was adopted to simulate the solid-liquid two-phase flow in the model pump. To verify the results of simulation, a wear test rig was set up to study the abrasion of impellers during the operation of pumps. The results of simulation and test showed that: the distribution of volume fraction of solid-phase has a good agreement with the wear pattern of hydraulic components in impellers during the wear test, and the two-phase flow field achieved by simulation can be used to explain the generation of abrasion. The areas with relatively more severe abrasion in impeller passages are located at the inlet edge of blades, the surface of the back shroud near the inlet edge and pressure side, as well as the junction between the pressure side and back shroud which does not extend to the outlet edge, because the existence of low speed circulation at the inlet edge of blades can easily lead to the gathering of solid particles which will aggravate the abrasion of inlet edge. Additionally, the particles that flow into the passages have an axial speed, which make them move towards the back shroud, finally causing the impact, and the flow separation of particles occurs at the pressure side of blade near the outlet edge. The most severe abrasion are in the back blade passages located at the pressure side near the outlet edge of the impeller, and the abrasion pattern develops towards the hub, which leads to a parabolic wear shape. The abrasion at the other areas in the back blade passages can be neglected. The main reason obtained from the analysis which mainly causes the abrasion of back blades was the impact between the particles and the back blades induced by the back flow under the effect of high pressure at the volute tongue. Through the comparison of numerical and test results, the simulation method was proved to be viable in predicting the wear characteristics of impellers during the operation of pump, and the two-phase flow field achieved from simulation can provide some direction and reference information for optimization design.
Number of references:30
Main heading:Two phase flow
Controlled terms:Abrasion - Centrifugation - Computational fluid dynamics - Computer simulation - Design - Flow fields - Flow separation - High pressure effects - Impellers - Inlet flow  - Liquids - Numerical methods - Pumps - Slurry pipelines - Testing - Tribology - Turbulence models - Water management - Wear of materials
Uncontrolled terms:Centrifugal slurry pumps - Effect of high pressure - Engineering plastics - Experimental research - External characteristic - Hydraulic components - Slurry pumps - Solid-liquid two-phase flow
Classification code:408 Structural Design - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 444 Water Resources - 446 Waterworks - 601.2 Machine Components - 617 Turbines and Steam Turbines - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 723.5 Computer Applications - 801.3 Colloid Chemistry - 802.3 Chemical Operations - 921.6 Numerical Methods - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.21.009
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 19>

Accession number:20145100353365
Title:Furrow loose and ridge compaction plough layer improves spring maize yield and water use efficiency
Authors:Bai, Wei (1); Sun, Zhanxiang (2); Zheng, Jiaming (2); Hao, Weiping (1); Liu, Qin (1); Liu, Yang (2); Feng, Liangshan (2); Cai, Qian (2)
Author affiliation:(1) Key Laboratory of Dryland Agriculture, Ministry of Agriculture of the People's Republic of China, Beijing , China; (2) Tillage and Cultivation Research Institute, Liaoning Academy of Agricultural Sciences, Engineering Research Centre for Dryland and Water-Efficient Farming of Liaoning Province, Shenyang , China; (3) College of Land and Environment, Shenyang Agricultural University, Shenyang , China
Corresponding author:Sun, Zhanxiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:81-90
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Plough layer construction is regarded as one of important methods for solving rainfed farmland problems. In order to explore the effect of plough layer construction on crop yield and water use efficiency (WUE) of spring maize, four tillage methods, including up loose and down compaction plough layer (ULDC, CK), all loose plough layer (AL), furrow loose and ridge compaction plough layer (FLRC) and all compaction plough layer (AC), were carried out in a long-term experimental station of Fuxin. The result showed that the yield of spring maize was significantly influenced by different plough layer constructions. For the years of 2011 and 2012, the maize yield under FLRC was the highest, followed by those under AL and CK; the yield under AC was the lowest. The average maize yield of the two years under FLRC was 16.39% higher than that under CK, and the yield under AL was 5.30% higher than that under CK, which were contributed by the increase in hundred kernel weight; the yield under AC was 5.73% lower than that under CK. The above-ground biomass (AGB) of maize and the harvest index were also examined. The result showed a significant impact of different plough layer constructions on AGB and harvest index of the maize. The FLRC treatment in 2011 was significant different from the others (P&lt;0.05), while the difference between the treatments of AL and CK was not significant (P&gt;0.05). The yield under FLRC was 7.18%, 7.19% and 12.87% higher than those under AL, CK and AC, respectively. The yield under FLRC in 2011 was generally consistent with that in 2012, without significant difference (P&gt;0.05). The harvest indices for the four treatments ranged from 0.38 to 0.44. The findings also showed that soil moisture contents under of FLRC and AL were higher than those under AC and CK. The soil water storage (0-100 cm) under the four treatments (FLRC, AL, CK and AC) were 247.36, 248.97, 242.84 and 239.48 mm, respectively, indicating that FLRC and AL could efficiently loose soil, increase water penetration and soil water storage, and improve soil moisture contents significantly. For both normal year (2011) and wet year (2012), the soil under FLRC could utilize precipitation of growing season effectively, and promote precipitation use efficiency of maize. An 11.95% increase of rainfall use efficiency was observed under FLRC than that under CK in 2011; FLRC and AL showed the increases of 21.23% and 12.43% of rainfall use efficiency comparing to CK in 2012, respectively. WUE of the crops differed in different years and plough layer constructions. In 2011, a 15.68% increase in WUE was observed under FLRC comparing to that under CK, the similar trend was also appeared in 2012, a 23.13% increase for CK in WUE. Averaging the result of two year, an 18.43% increase in WUE was observed comparing to that of CK. Consequently, furrow loose and ridge compaction plough layer was an efficient construction for improving production and WUE of cropland in semi-arid zone of northeastern China.
Number of references:31
Main heading:Agricultural machinery
Controlled terms:Aluminum - Arid regions - Compaction - Crops - Cultivation - Efficiency - Harvesting - Moisture determination - Rain - Soil moisture  - Soils - Water supply
Uncontrolled terms:Above ground biomass - Efficient construction - Experimental stations - Precipitation use efficiencies - Soil water storage - Spring maize - Water use efficiency - Yield
Classification code:443 Meteorology - 443.3 Precipitation - 444 Water Resources - 446.1 Water Supply Systems - 483.1 Soils and Soil Mechanics - 536.1 Powder Metallurgy Operations - 541.1 Aluminum - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.21.011
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 20>

Accession number:20145100353380
Title:Algorithm for damaged leaf segmentation based on block mark
Authors:Zhang, Shuifa (1); Wang, Kaiyi (1); Zu, Qin (2); Huang, Shan (1); Pan, Shouhui (1); Wang, Zhibin (1); Li, Mingyuan (4)
Author affiliation:(1) Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing , China; (2) Academy of State Administration of Grain, Beijing , China; (3) National Engineering Research Center for Information Technology in Agriculture, Beijing , China; (4) Institute of Plant Protection and Environment Protection, Beijing Academy of Agricultural and Forestry Sciences, Beijing , China
Corresponding author:Wang, Kaiyi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:218-225
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Damaged leaf is one of the important factors leading to crop loss. Damaged leaf segmentation provides an important basis for diseased leaf detection, and for proper preventive measures to be taken. Advances in technology have made it possible for a computer with image processing techniques to segment the diseased leaf in an image of a green plant and evaluate the severity of the infestation. The research objects based on image segmentation and processing are the leaves damaged by pests or nutrient deficiency. The procedure of image segmentation algorithm was developed in C that targets a diseased green leaf including the normal leaf and diseased regions. In current researches, algorithms based on thresholding or clustering are widely used. Despite of the simplicity and efficiency, the performances of these methods are not satisfactory due to the grayscale overlapping among background, plant leaves and damaged leaves in field environment. In consideration of the stability edge feature of images and the gray value consistency of leaves, a novel method was proposed to segment the damaged leaves in field environment by combining Canny edge detection and block mark, which is robust with respect to the changes in illumination and noises, and efficient to evaluate the damage degree of the leaves. Image processing was used to transform the image to gray scale, extract the Canny edge, perform Canny edge clustering, remove noise, detect the external rectangle, extract connected components which are 4-connected, classify regions, and finally segment the diseased regions of the green leaf. The block mark based algorithm was introduced to segment the damage leaf. The experiments were conducted on Malabar spinach, tomato, cucumber, eggplant, peach, pepper, dolichos lablab images captured on sunny day, and towel gourd, calabash, melon, eggplant and cucumber images captured on cloudy day. (1) The classification accuracy of the Malabar spinach on a sunny day was 98.8%; and 95.4%, 98.5%, 98.4%, 98.8%, 99.1%, 99.5% for tomato, cucumber, towel gourd, peach, pepper, dolichos lablab,,respectively, and the average classification accuracy for the test images was 98.4%. The classification accuracy of the towel gourd on a cloudy day was 96.5%, and 97.1%, 95.6%, 96.4%, 88.5% for calabash, cucumber, melon, eggplant, respectively, and the average for the test images was 96.5%. (2) The classification false rate of the test images captured on a sunny day for the Malabar spinach was 0.3%, and 1.2%, 0.2%, 1.2%, 0.1%, 0.0%, 0.1% for tomato, cucumber, towel gourd, peach, pepper, dolichos lablab, respectively, and the average for the test images was 0.3%. The classification false rate on a cloudy day for the towel gourd was 0.1%, and 0.0%, 0.5%, 0.1%, 0.2% for calabash, cucumber, melon, eggplant, respectively, and the average for the test images was 0.2%. (3) The average false rates on the sunny sets and the cloudy sets for leaves damage degree were 2.340% and 1.475%, respectively. Experimental results showed that the proposed method could effectively separate damaged leaves apart from background. The method provided higher precision as well as the accurate and closed boundaries, which was beneficial to evaluate the damage degree of leaves.
Number of references:30
Main heading:Image segmentation
Controlled terms:C (programming language) - Clustering algorithms - Computer vision - Damage detection - Disease control - Edge detection - Fruits - Nutrients - Plants (botany) - Testing
Uncontrolled terms:Block mark - Canny edge detection - Classification accuracy - Connected component - Image processing technique - Image segmentation algorithm - Nutrient deficiency - Preventive measures
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 422.2 Strength of Building Materials : Test Methods - 461 Bioengineering and Biology - 716 Telecommunication; Radar, Radio and Television - 721 Computer Circuits and Logic Elements - 723.5 Computer Applications - 741.1 Light/Optics - 821.4 Agricultural Products
DOI:10.3969/j.issn.1002-6819.2014.21.026
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 21>

Accession number:20145100353392
Title:Development of device for releasing and collecting jasmine flower fragrance and its adsorption test
Authors:Ye, Qiuping (1); Jin, Xinyi (1); Xu, Xiaodong (1); Zheng, Gongyu (1); Chen, Shousong (1); Wang, Tingting (1)
Author affiliation:(1) College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou , China
Corresponding author:Jin, Xinyi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:316-323
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Jasmine scented tea is a kind of flavored tea. It is popular for its elegant aroma and mellow taste. Jasmine flower is a typical "temperament flowers", it blooms at night when it releases fragrant aroma. In traditional jasmine tea processing, the tea and the jasmine flower are mixed together during which the materials are spread for heat dissipation, when the temperature increasing and the tea is re-dried. The process is repeated for several times. However, many problems exist with this type of production, including its complicated process, longer production period, higher labor intensity, higher flower consumption, seasonal and field limitations. To solve these problems, technological processes have been developed that employ a device to absorb the aroma of jasmine flowers, perform a clean extraction of essential oil, and produce jasmine tea with the oil.
Number of references:22
Main heading:Odors
Controlled terms:Activated carbon - Adsorption - Control systems - Environmental management - Essential oils - Humidity control - Mass spectrometry - Oil shale - Principal component analysis - Processing  - Quality control - Solvent extraction - Warehouses
Uncontrolled terms:Aroma quality - Aroma releasing - Chromatography-mass spectrometry - Device - Environment control systems - Environmental control system - Environmental parameter - Jasmine flower
Classification code:402 Buildings and Towers - 402.1 Industrial and Agricultural Buildings - 451.1 Air Pollution Sources - 454.1 Environmental Engineering, General - 512.1 Petroleum Deposits - 731.1 Control Systems - 801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 913.3 Quality Assurance and Control - 913.4 Manufacturing - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.21.038
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 22>

Accession number:20145100353376
Title:Discrimination between hydromorphic alluvial sandy mud paddy and tide sandy mud paddy based on hyperspectral characteristics
Authors:Guo, Xi (1); Xie, Biyu (3); Ye, Yingcong (3); Xie, Wen (3)
Author affiliation:(1) Institute of Soil &amp; Fertilizer and Resource &amp; Environment, Jiangxi Academy of Agricultural Sciences, Nanchang , China; (2) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing , China; (3) College of Land Resources and Environment, Jiangxi Agricultural University, Nanchang, China
Corresponding author:Guo, Xi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:184-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The application of hyperspectral analysis techniques can extract hyperspectral characteristic parameters and identify soil types. In contrast to the traditional methods, this application is more convenient and time-saving. This paper took two types of Typic Hapli-Stagnic Anthrosols (the hydromorphic alluvial sandy mud paddy and the hydromorphic tide sandy mud paddy) in Xingguo County as the research objects to analyze the hyperspectal characteristics and to extract the effective hyperspectral absorption characteristic parameters (SAFP) for the two soils. In the research, we used three hyperspectral methods including the hyperspectral resample process, the continuum removal, and the first-order differential transform of hyperspectral reflectivity. The results showed that the wavelength position of peaks and valleys can be used to effectively identify the two different Anthrosols. The wave peak width, the wave valley width and the wave valley tilt angle were the parameters to distinguish the two types of Anthrosols. In addition, the analysis of the hyperspectral characteristics parameters after the hyperspectral resample process showed that the difference between the two types of soils was the wave peak reflectivity, and the wave peak reflectivity was the most effective parameter. The hydromorphic alluvial sandy mud paddy belonged to the high reflectivity mud type. The declining rate of the hydromorphic alluvial sandy mud paddy hyperspectral reflectivity was larger and the hyperspectral curve absorption width was significantly larger than that of the hydromorphic tide sandy mud paddy. Moreover, the analysis of the hyperspectral characteristics parameters after the continuum removal showed that the wave valley width can be used to distinguish the two types of Typic Hapli-Stagnic Anthrosols. The wave valley widths of the two soils were 26 and 178 nm, respectively in the vicinity of the wavelength 480 nm. Finally, the analysis of the hyperspectral characteristics parameters after the first-order differential transform of hyperspectral reflectivity showed that the wave valley tilt angle was the other effective parameter to distinguish the two types of Anthrosols. The wave valley tilt angle of the hydromorphic alluvial sandy mud paddy and the hydromorphic tide sandy mud paddy were -0.00573&deg; and 0.00573&deg;, respectively at the wavelength 471 nm. This showed that the hyperspectral reflectivity increase trend of the hydromorphic alluvial sandy mud paddy was negative in the vicinity of the wavelength 471 nm, while the hyperspectral reflectivity increase trend of the hydromorphic tide mud paddy was positive in the vicinity of the wavelength 471 nm. This paper can provide a reference for the application of hyperspectral analysis techniques to identify different Stagnic Anthrosols soil.
Number of references:16
Main heading:Reflection
Controlled terms:Algorithms - Landforms - Soils - Spectrum analysis
Uncontrolled terms:Absorption characteristics - First-order differentials - Hydromorphic alluvial sandy mud paddy - Hydromorphic tide sandy mud paddy - Hyper-spectral characteristics - HyperSpectral - Hyperspectral analysis - Jiangxi Province
Classification code:481.1 Geology - 483.1 Soils and Soil Mechanics - 711 Electromagnetic Waves - 723 Computer Software, Data Handling and Applications - 921 Mathematics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.21.022
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 23>

Accession number:20145100353385
Title:Analysis of land system change and its spatial agglomeration pattern in sandy area of northern Yanchi during past 25 years
Authors:Wang, Manman (1); Wu, Xiuqin (1); Wu, Bin (1); Zhang, Yuqing (1); Dong, Guihua (3)
Author affiliation:(1) Key Laboratory of Soil and Water Conservation and Desertification Combating, Ministry of Education, Beijing Forestry University, Beijing , China; (2) Yanchi Ecology Research Station, School of Soil and Water Conservation, Beijing Forestry University, Beijing , China; (3) China National Environmental Monitoring Centre, Beijing , China
Corresponding author:Wu, Xiuqin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:256-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:For discussing the change of land system and spatial agglomeration pattern in sandy area of northern Yanchi during the past 25 years, land use vector data from the interpretation of TM remote sensing images (in the years of 1989, 1995, 2000 and 2007) and ZY-1 O2C satellite image (in the year of 2012) were used as the data sources. The spatial-temporal dynamic change characteristics were comprehensively analyzed by building land use change network model and information entropy model. The former model was used to quantify some elements such as direction, status and trend, which could effectively characterize some significant aspects associated with land change; the latter model was used to describe and express the order degree of the land use system. Furthermore, the spatial agglomeration pattern was expressed by using the GIS density mapping method. Results showed that tremendous changes had taken place in the past 25 years for the land use types in sandy area of northern Yanchi. Cultivated land and unused land showed a drastic reduction, while woodland and grassland expanded significantly, and human activities in the study area were in a positive way to gradually optimize and influence the evolution of landscape pattern Different degrees of mutual transformation appeared between various land use types, among which grassland, woodland, cultivated land and unused land played key roles in the whole network of land use change, and thus determined the characteristics of land use change in the sandy area. The land system change process showed an evolution trend from "balanced" type, "weak balanced" type to "not balanced" type during the past 25 years. Information entropy and equilibrium degree of land use structure was in a fluctuation drop situation, while advantage degree was in a fluctuation upward trend; overall, the land use system of the study area was developing towards a relatively orderly state. From the perspective of spatial analysis, the regions near woodland and cultivated land were hot spots of land use change and the spatial agglomeration features of land use change were different at different periods. Taking the year of 1995 as the demarcation point, the hot zone of land use change was distributed from northeast to southwest direction from 1989 to 1995, however, the hot spot gradually transferred from west to east of the whole region from 1995 to 2012. Through the restoration of vegetation, the ecological environment in the study area had been improved to a large extent, and a land use pattern dominated by grassland and woodland had been formed gradually, effectively reducing the risk of desertification. These conclusions could provide a scientific basis for the research on the mechanism of land use change, sustainable use of land resources, as well as optimization of sandy habitat environment.
Number of references:45
Main heading:Land use
Controlled terms:Agglomeration - Entropy - Forestry - Geographic information systems - Image reconstruction - Information use - Remote sensing
Uncontrolled terms:Ecological environments - Information entropy - Land-use change - Land-use structures - Mutual transformations - Remote sensing images - Sandy area of northern Yanchi - Spatial agglomeration patterns
Classification code:403 Urban and Regional Planning and Development - 641.1 Thermodynamics - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 802.3 Chemical Operations - 821.0 Woodlands and Forestry - 903.3 Information Retrieval and Use
DOI:10.3969/j.issn.1002-6819.2014.21.031
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 24>

Accession number:20145100353377
Title:Comparative analysis of various hyperspectral prediction models of fluvo-aquic soil organic matter
Authors:Guo, Doudou (1); Huang, Shaomin (1); Zhang, Shuiqing (1); Nie, Shengwei (1)
Author affiliation:(1) Institute of Plant Nutrient and Environmental Resources, Henan Academy of Agricultural Sciences, Zhengzhou , China
Corresponding author:Huang, Shaomin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:192-200
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the continuous development and wide application of multivariate statistical analysis methods, more and more spectral pre-processing and modeling methods are used to analyze the spectral data in order to establish high-precision hyperspectral prediction models. This study selected soil samples from National Long-term (more than 20 years) Monitoring Station of Fluvo-aquic Soil Fertility and Fertilizer Effects. The soil can represent Huang-Huai-Hai Fluvo-aquic soil type and fertilization models. A total of 83 soil samples were collected from the depth of 0-20 cm from treatments with different ratio of fertilization. Reflectance measurements from 350 nm to 2 500 nm were obtained using FieldSpec 3 Hi Spectroradiometer (Analytical Spectral Devices Inc.) in laboratory after soils were air-dried and sieved (0.18 mm). Twenty five pre-processing methods including 15 single pre-processing methods (standard normal variate transformation, normalization, multiple scatter correction, derivative method with different smoothing points and operational parameters) and 10 pre-processing methods adding operations of spectral data and three multivariate techniques (stepwise multiple linear regression, SMLR,partial least-squares regression, PLSR,support vector machine regression, SVMR) were compared with the aim of identifying the best combination to predict fluvo-aquic soil organic matter content. The coefficient of determination, the root mean square error (RMSEv) and relative prediction deviation (RPD) of validation set were used to evaluate the models. The result showed that the best multivariate technique was PLSR, which associated with variety pre-processing methods could resulted in high accuracy and reliability of models. The averaged coefficient of determination, RMSEv and RPD of 25 prediction methods were 0.913, 1.264 g/kg and 3.299 respectively. The optimal pre-processing method varied with the multivariate technique used. Compared with the single pre-processing methods, pre-processing methods add operations were better for data preparation among the 3 multivariate techniques, of which average coefficient of determination was higher 0.049, 0.033and 0.071 than the single ones, respectively, and the average RPD was higher 0.530, 0.307 and 1.144 than the single ones, respectively, but the average RMSEv lower 0.318, 0.204 and 0.528 g/kg than the single ones, respectively. The optimal pre-processing method was multiple scatter correction added Savitzky-Golay 1st derivative with a search window of 5 measurements(MSC-SGF5-2) since it performed best among the 3 multivariate techniques, with the average coefficient of determination=0.934, RMSEv=1.17 g/kg and RPD=3.59. This pre-processing method probably can be used as a common spectral data preparation method for fluvo-aquic soil organic matter content prediction model. Among the tested models,the best prediction model for fluvo-aquic soil organic matter was PLSR multivariate techniques associated with normalization by the maximum value pre-processing method (coefficient of determination=0.948, RMSEv=0.972 g/kg, RPD=4.276), and it has high accuracy, reliability and was easy to operate.
Number of references:31
Main heading:Processing
Controlled terms:Biogeochemistry - Biological materials - Fertilizers - Forecasting - Least squares approximations - Linear regression - Linear transformations - Mathematical models - Mathematical transformations - Mean square error  - Metadata - Models - Multivariant analysis - Organic compounds - Soil surveys - Soils - Spectrum analysis
Uncontrolled terms:Coefficient of determination - Comparison - Fluvo-aquic soils - Multivariate statistical analysis - Partial least-squares regression - Standard normal variate transformations - Stepwise multiple linear regression - Support vector machine regressions
Classification code:461.2 Biological Materials and Tissue Engineering - 481.2 Geochemistry - 483.1 Soils and Soil Mechanics - 723 Computer Software, Data Handling and Applications - 804 Chemical Products Generally - 804.1 Organic Compounds - 902.1 Engineering Graphics - 913.4 Manufacturing - 921 Mathematics - 922 Statistical Methods - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.21.023
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 25>

Accession number:20145100353367
Title:Hydrochemical characteristics of groundwater before and after water-saving reform in Hetao Irrigation District, Inner Mongolia
Authors:Li, Bin (1); Shi, Haibin (1); Zhang, Jianguo (3); Li, Zhen (1)
Author affiliation:(1) College of Water Conservancy and Civil Engineering, Inner Mongolia Agriculture University, Hohhot , China; (2) Institute of Resources and Environment and Testing Technology of Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot , China; (3) Institute of Water Conservancy Science, Bayannur, Linhe ; Inner Mongolia, China
Corresponding author:Shi, Haibin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:99-110
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The purpose of the research is to validate the water environment changes of regional soil after implementing the water-saving upgrading program. The background of this research is about program implementation of water-saving upgrading in North irrigation district. The groundwater samples were analyzed scientifically and systemically in Inner Mongolia Hetao irrigation district, then the descriptive statistics, the correlation matrices, the ratio coefficient of the main ions and the graphical method (including the H.. diagram, the piper diagram and Multi-rectangular diagram) were utilized to gain the better understanding of the spatial-temporal variability of the characteristics and the evolution rule of groundwater hydrochemistry in Hetao irrigation district of Inner Mongolia. The results showed that evaporation concentration, lixiviation and cation exchange were the main hydrological chemical processes which controlled the evolution of groundwater quality in irrigation district. Compare with the 2007 (before water-saving upgrading), the absolute content of HCO<inf>3</inf>^- has change from smallest to largest in anion which becoming the main anion in the groundwater on 2008 and 2009. Coefficient of variation of Ca², Mg², HCO<inf>3</inf>^- had few change and kept in a stable content in the groundwater. In addition, coefficient of variation of Na, Cl^-, SO<inf>4</inf>^2- had a large change in the groundwater. As a result, Na, Cl^-, SO<inf>4</inf>^2- became a susceptibility factor varying with environmental factors and major variables that determined in groundwater salinization effect. The main chemical types of ground water were HCO<inf>3</inf>-Na (middle and lower reaches), SO<inf>4</inf>-Na (downstream) and Cl-Na (upstream) in irrigation district. Moreover, compared with the 2007, the concentration of HCO<inf>3</inf>^- was increasing, but the concentration of Cl^- and Na were decreasing. The groundwater was changing to more desalt water and small harm for crop. There was a complex spatiotemporal variation of chemical types for ground water. To follow the direction of groundwater flow, the chemical types of groundwater had been changed from Na-Ca-Mg-Cl-SO<inf>4</inf>-HCO<inf>3</inf>, Na-Mg-Cl-SO<inf>4</inf>-HCO<inf>3</inf> and Na-Mg-Ca-HCO<inf>3</inf>- SO<inf>4</inf>-Cl to Na-Cl-SO<inf>4</inf>, Na-SO<inf>4</inf>-HCO<inf>3</inf> and Na-Mg-Cl-HCO<inf>3</inf>. Furthermore, the chemical types of groundwater had been changed from Ca-Na-Mg-HCO<inf>3</inf>-SO<inf>4</inf>-Cl, Na-Mg-Ca-HCO<inf>3</inf>-SO<inf>4</inf>-Cl and Na-Mg-Cl-HCO<inf>3</inf>-SO<inf>4</inf> to Na-Cl-HCO<inf>3</inf>-SO<inf>4</inf>, Na-HCO<inf>3</inf>-Cl-SO<inf>4</inf> and Na-Ca-HCO<inf>3</inf>-SO<inf>4</inf>-Cl in 2008. In 2009 the chemical types of groundwater had been changed from Na-Ca-Cl-SO<inf>4</inf>-HCO<inf>3</inf>, Na-Mg-Ca-HCO<inf>3</inf>-SO<inf>4</inf>-Cl and Na-Mg-Ca-Cl-HCO<inf>3</inf>- SO<inf>4</inf> to Na-HCO<inf>3</inf>-Cl-SO<inf>4</inf>, Na-Cl-SO<inf>4</inf> and Na-Ca-Mg-Cl-SO<inf>4</inf>-HCO<inf>3</inf>. The Na had absolute predominance trend. Therefore, in chemical type aspect, HCO<inf>3</inf>^- of anion in 2008 and 2009 was more primary chemical type than HCO<inf>3</inf>^- of anion in 2007. The research results can give the references to evaluate the impacts of the water-saving upgrading program on water environment of regional soil.
Number of references:30
Main heading:Rivers
Controlled terms:Calcium - Chlorine - Groundwater - Groundwater flow - Groundwater geochemistry - Hydrochemistry - Ions - Irrigation - Magnesium - Quality control  - Water conservation - Water quality
Uncontrolled terms:Coefficient of variation - Evolvement rule - Groundwater salinizations - Hetao irrigation districts - Hydrochemical characteristics - Spatial temporals - Spatio-temporal variation - Water - savings
Classification code:444 Water Resources - 453.2 Water Pollution Control - 481.2 Geochemistry - 549.2 Alkaline Earth Metals - 801 Chemistry - 804 Chemical Products Generally - 821.3 Agricultural Methods - 913.3 Quality Assurance and Control
DOI:10.3969/j.issn.1002-6819.2014.21.013
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 26>

Accession number:20145100353357
Title:Study on self-adaptive centering method of removing core of lotus seed and prototype test
Authors:Ma, Qiucheng (1); Lu, Ange (1); Chen, Kai (1); Zhao, Fumin (1); Lei, Lintao (1); Zhang, Jing (1)
Author affiliation:(1) School of Mechanical Engineering, Xiangtan University, Xiangtan, China
Corresponding author:Ma, Qiucheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:17-24
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Lotus seed has very high nutritional and medicinal value, which consists of lotus shell, lotus kernel and lotus core. Because of the bitter taste, the lotus cores need to be removed before eating. The existing equipment for removing core can remove the lotus core fast by operating the coring bit. Before drilling, the lotus kernel has to be centered in the centering working position. The centering device generally consists of two rotating rollers. Under the action of gravity and friction force, the lotus kernel can be centered in the rotating process. However, the position of the coring bit is fixed in the centering working position, and therefore the drilling deviation occurs due to the diameter variation of lotus kernels, and the lotus cores cannot be removed effectively, which lowers the quality of lotus kernels directly. To solve the above problems, the classification process is applied widely. However, it is ineffective owing to the inaccuracy of the classification process and the high requirement for staff and equipment. In order to avoid this situation, the shape parameters of lotus kernels are firstly measured and analyzed in this paper. The results show that the maximum cross section of the lotus kernel is almost round with a mean roundness deviation of 0.46 mm and the diameter ranges from 9 to 16 mm; the average chordwise curvature radius is 7.764 mm, and the average longitudinal curvature radius is 5.177 mm, therefore, the shape of a lotus kernel can approximate to an ellipsoid. Moreover, the centering deviation of the double roller rolling centering method presents a maximum value of 6.654 mm. Aiming at solving the problem of drilling deviation in the automated coring of lotus seeds, this paper proposes a self-adaptive centering method for lotus seeds based on a slider-crank mechanism and a parallel crank mechanism. By utilizing this method, the position of the coring bit can be automatically adjusted according to the lotus kernel size. A mathematical model of self-adaptive centering is established by the complex number vector method. Once the parameters of the linkages are selected, the centering deviation value is determined. For the self-adaptive centering mechanism, the optimization of the linkage parameters is complicated and difficult to meet the demand through traditional optimization methods. Therefore, in order to make the centering deviation minimum, by utilizing the stochastic optimization algorithm of Cuckoo Search, this paper optimizes the linkage parameters in MATLAB. The initial parameters are as follows: the nest number is 25, the probability of detection is 0.25, and the maximum iteration number is 4&times;10⁵. The optimized parameters of connecting rod are 88.51, 135.72, 0.12828, and 125.35 mm respectively, and the coaxial deviation between the coring bit axis and lotus kernel axis is lower than 0.05mm. Based on the above study, a self-adaptive machine for removing core of lotus seed was developed and a coring experiment with 400 samples of lotus seeds was carried out. The experimental parameters were as follows: the working cycle was 1.5 s, the roller's rotating speed was 238 r/min, the pressure of the pressing wheel was 25 N, the coring bit diameter was 2.5 mm and the drill speed was 2800 r/min. By measuring the circle run-out value at the maximum cross section of the lotus kernel, the drilling accuracy of lotus seeds were calculated. The results show that the drilling accuracy of a self-adaptive machine for removing core of lotus seed is 91.25%, much higher than that of the existing equipment, which is 60%-70%; moreover, this machine can handle different sizes of lotus kernels. The experimental results verify the effectiveness and practicability of this self-adaptive centering method.
Number of references:21
Main heading:Iterative methods
Controlled terms:Agricultural machinery - Algorithms - Automation - Drilling equipment - Equipment - Friction - Mathematical models - Optimization - Rollers (machine components)
Uncontrolled terms:Adaptive centering - Bar linkages - Complex number vector method - Cuckoo searches - Experimental parameters - Lotus kernel coring - Probability of detection - Stochastic optimization algorithm
Classification code:601.2 Machine Components - 604.2 Machining Operations - 731 Automatic Control Principles and Applications - 732 Control Devices - 821.1 Agricultural Machinery and Equipment - 901 Engineering Profession - 921 Mathematics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.21.003
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 27>

Accession number:20145100353356
Title:Research on seed-filling mechanism of vertical shallow basin type seed-metering device with composite filling force
Authors:Liu, Hongxin (1); Xu, Xiaomeng (1); Guo, Lifeng (1); Shang, Jiajie (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin , China
Corresponding author:Liu, Hongxin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:9-16
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:On account of the decreasing of filling ability of hole at high operating speed caused miss-seeding, even leaded to reduce production, mechanical precision seed-metering device was gradually eliminated from application markets. How to improve the filling ability of mechanical precision seed-metering device to meet the mechanization requirements at high operating speed was the key point of the research. Because the mechanical precision seed-metering device could only depend on gravity, centrifugal force and interaction force between the seeds to complete filling seeds, mechanics characteristics and regulation of soybean seeds which were in the cavity of seed-metering device in all directions were analyzed from the mechanics point of view. And due to the structure characteristic of seed-metering device and granular mixtures characteristic of soybean seeds, the value of filling force in the form of compressive stress was limited. In this paper the model of filling force of hole was built and it could be easily found that increasing the kinds of filling force was an effective way to improve filling ability of the mechanical precision seed-metering device, so a vertical shallow basin type seed-metering device was innovatively designed. The structure of new type seed-plate was based on the traditional vertical seed-plate. The end plane of vertical seed-plate's hole was been folded into shallow basin shape, and then the filling holes were arranged evenly around the side wall of seed-plate along the circumferential direction, which could not only keep the advantages of vertical seed-plate, but also take full advantage of gravity and centrifugal force to increase the filling force of seed-plate. Owing to the existence of folded edge, soybean seeds could slip off from the inclined plane of seed-plate and leave seed-plate in the process of cleaning seeds, avoiding the negative effects generated by the centrifugal force in the process of cleaning seeds, ensuring the reliability of filling seeds. EDEM (engineering discrete element method) software was utilized to simulate and analyze, and then physical prototype experiment was conducted to verify the theoretical analysis and simulation results. Taking the traditional vertical seed-metering device and shallow basin type seed-metering device as experimental subjects and the rotational speed of seed-plate as experimental factor, the single factor contrast experiments were conducted. The experiment results show that the simulated and experimental values of variation trend of filling rate are basically the same and the simulation value is close to experimental value, the minimum relative error is 0.4%, and the maximum relative error is 2.91%.The filling rate of shallow basin type seed-metering device is higher than vertical seed-metering device, especially at high operating speed. At the rotational speeds of 39.21, 49.12, 58.82 r/min, simulation values are higher by 2.4%, 3.4%, 2.6% and experimental values are higher by 2.59%, 1.58%, 3.04%, and average filling rate is higher by 2.33%, which verifies the components of gravity and centrifugal force which are as composite force can make a contribution to fill seeds and can be obviously helpful for seeds to come into the hole when increasing the rotational speed of seed-plate, and provides the guidance and direction for the research of mechanical precision seed-metering device.
Number of references:22
Main heading:Filling
Controlled terms:Agricultural machinery - Computer simulation - Computer software - Experiments - Mixtures - Models - Plates (structural components) - Pneumatic materials handling equipment - Seed - Speed
Uncontrolled terms:Analysis and simulation - Circumferential direction - Maximum relative errors - Mechanics characteristics - Seed-metering device - Shallow basins - Simulation - Structure characteristic
Classification code:408.2 Structural Members and Shapes - 691.1 Materials Handling Equipment - 691.2 Materials Handling Methods - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 802.3 Chemical Operations - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 902.1 Engineering Graphics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.21.002
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 28>

Accession number:20145100353375
Title:Detection of late rice's planting area change in Pingle County based on multi-temporal remote sensing images
Authors:Huang, Wei (1); Huang, Jinliang (1); Wang, Lihui (1); Hu, Yanxia (1); Han, Pengpeng (1); Wang, Jiuling (1)
Author affiliation:(1) Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan , China; (2) University of Chinese Academy of Sciences, Beijing , China
Corresponding author:Huang, Jinliang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:174-183
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rice is the most important food crop in China and its production ranks first in three major grain crops which are wheat, rice and corn. Therefore, it is very important to understand planting area and growth of rice. Because change detection is time-sensitive, remote sensing data is often used as a data source for it. Most of widely-used change detection methods using TM image are at pixel level, or only use image of single time phase. Based on multi-temporal Landsat TM images, this research extracted change area of rice planting in Pingle County. The process explored the methods of calculating changes in intensity and determining the threshold. First, the paper selected images of heading stage and harvest stage as data sources, and except for crops, there are no significant changes of ground objects in a few months. Since the spectral characteristics of late rice in the two periods are different from those of other crops, the changes of the images at two stages in the same year could be used to extract the change area of rice planting. In the process, change vector analysis method, correlation coefficient method and vector similarity method were used to calculate the change intensity. Otsu method, minimum error rate method and the method based on double window with variable step size were used to determine the threshold of the change intensity map. The change area maps of rice planting extracted by nine combinations of the methods were compared. Comprehensive utilization of three methods for extracting changes could get change area of rice planting with higher accuracy. This paper chose minimum error rate method based on histogram curvature or the method based on double window with variable step size to determine the threshold. The intersection of change area based on change vector analysis method and change area based on correlation coefficient method could inhibit the pseudo change of river beach and mountain shadow. Then the rice area was extracted exactly according to the difference between NDVI values and the object-oriented method. In order to refine the change detection of rice planting areas, the change areas of all ground objects and the change area of rice planting in two years were intersected to get the final variation for rice planting area. The results showed that the inhibitory effect of change vector analysis method for river beach change was better than correlation coefficient method, and yet the inhibition effect of correlation coefficient method for mountain shadow was better than change vector analysis method. Besides, vector similarity method was sensitive to mountain shadow and had low sensitivity to paddy field change. Among the three threshold determination methods, minimum error rate method was more accurate than Otsu method and more stable than the method based on double window with variable step size. Finally, the overall accuracy of change detection for late rice's planting area in Pingle County reached 96.8% in confusion matrix for verification. The error of the change area was 2.85% compared with the statistical data. This method could effectively extract the change of rice planting area in Pingle County.
Number of references:35
Main heading:Remote sensing
Controlled terms:Beaches - Crops - Extraction - Image reconstruction - Signal detection - Vectors
Uncontrolled terms:Change detection - Comprehensive utilizations - Correlation coefficient - Correlation coefficient method - Multi-temporal remote sensing - Object oriented - Rice - Spectral characteristics
Classification code:407.3 Coastal Engineering - 716.1 Information Theory and Signal Processing - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 802.3 Chemical Operations - 821.4 Agricultural Products - 921.1 Algebra
DOI:10.3969/j.issn.1002-6819.2014.21.021
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 29>

Accession number:20145100353388
Title:Ecological regionalization of grain storage in Jilin based on water and heat balance model of grain
Authors:Wu, Wenfu (1); Guo, Hongwei (1); Xu, Yan (1); Zhang, Yaqiu (1); Chen, Siyu (4); Shen, Jin (3); Liu, Qing (3); Shi, Yanfang (3)
Author affiliation:(1) College of Biological and Agricultural Engineering, Jilin University, Changchun , China; (2) Information Exchange Center of the State Administration of Grains, Beijing , China; (3) Chinese Academy of Agricultural Engineering, Beijing , China; (4) College of Mechanical Engineering, Jiamusi University, Jiamusi , China
Corresponding author:Xu, Yan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:286-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:According to all the weather data of cities and counties in Jilin Province from 2001 to 2012 publicly released by the National Weather Service, this paper took the corn as research object, and calculated the equilibrium moisture content of grain by combining the effects of temperature and relative humidity on grain storage through grain heat and humid balance theory and model, and adopted the spatial data analysis tool of GIS together with mathematical cluster analysis to delimit the ecological area for food storage in Jilin Province, which overcame the drawbacks of single factor division and provided a reliable scientific basis for grain storage safety. Jilin grain storage area can be divided into three zones: Zone I is western plains of Jilin Province, including Baicheng, Changchun, Siping; Zone II is in middle eastern area of Jilin Province, including Jilin, Liaoyuan, Meihekou, Tonghua and some areas of Hakusan; Zone III is eastern mountainous region of Jilin Province, including Yanbian, Changbai and other areas. And food storage areas have different characteristics. Among three zones, Zone I is located in the central and western plains of Jilin Province, which has higher temperature, smaller precipitation, smaller air relative humidity, bigger wind speed and longer sunshine hour. The climate is conducive to air circulation and suitable for grain storage. Therefore, this area is the best one among the ecological areas for grain storage in Jilin. The grain storage area should pay attention to reducing the grain temperature in the months from June to September, and mechanical cooling can be considered to solve the problem. Ecological grain storage mode should be continuous drying in medium-sized cooperatives and centralized storage of warehouse rations in this area. Zone II is located in the Mid-eastern area of Jilin Province. Maybe due to the higher altitude, the region has higher air relative humidity, higher temperature, larger precipitation, minimum wind speed and shorter sunshine hour. This grain storage area from June to September should pay attention to ventilation, and mechanical ventilation can reduce the grain temperature. The main mode of grain storage should be small continuous drying and dry food storage in warehouse in this area. Zone III is in the eastern mountains of Jilin Province. The climate is rather special in this region, which is east of the Sea of Japan, so climate is humid. This region is in the Changbai Mountain area and altitude is high, so this region has shorter daylight hour, higher air humidity, lower temperature, and larger precipitation and wind speed. Therefore, grain storage in this area should be considering technical measures such as mechanical ventilation and precipitation from June to September. And the main grain storage mode should be grain storage in farmers' warehouse together with precipitation, plus centralized storage of warehouse rations in this area. Equilibrium moisture content and equilibrium relative humidity are predicting trends of grain moisture, environment condition during grain storage is the determinants of changes of grain moisture content, and the appropriate treatment measures have important and extensive effect. This study analyzes the characteristics of climate in each grain storage area for appropriate method recommendation of grain storage. Dividing food storage area provides a scientific basis for scientific grain storage and grain storage security, and provides a theoretical basis for establishing applied technology and management systems according to the characteristics of China's grain storage area.
Number of references:17
Main heading:Food storage
Controlled terms:Cluster analysis - Digital storage - Ecology - Energy storage - Grain (agricultural product) - Moisture - Moisture determination - Network security - Safety factor - Specific heat  - Temperature - Thermal processing (foods) - Ventilation - Warehouses - Wind
Uncontrolled terms:Effects of temperature - Environment conditions - Equilibrium moisture contents - Equilibrium relative humidity - Grain moisture content - Heat balance model - Mechanical ventilation - National Weather Services
Classification code:402.1 Industrial and Agricultural Buildings - 443.1 Atmospheric Properties - 454.3 Ecology and Ecosystems - 641.1 Thermodynamics - 643.5 Ventilation - 662.1 Automobiles - 702 Electric Batteries and Fuel Cells - 722.1 Data Storage, Equipment and Techniques - 723 Computer Software, Data Handling and Applications - 821.4 Agricultural Products - 822.1 Food Products Plants and Equipment - 822.2 Food Processing Operations - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.21.034
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 30>

Accession number:20145100353389
Title:Integrated index assessing effect of magnetic treatment on liquid water's associative structure
Authors:He, Jinsong (1); Qi, Fanyu (2); Pei, Luowei (2); Yang, Hongwei (3); Cai, Ran (3); Ye, Zhangying (2)
Author affiliation:(1) College of Food Science and Technology, Yunnan Agricultural University, Kunming , China; (2) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou , China; (3) School of Environment, Tsinghua University, Beijing , China
Corresponding author:Ye, Zhangying
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:293-300
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The application of magnetic water in the agriculture and water treatment has been getting a lot of attention. However, it is still difficult to quantify the effect of magnetic treatment on the liquid water structure. In this study, the effects of magnetic treatment on the internal energy, surface entropy, and free water ratio of liquid water were studied by the analysis of viscosity, surface tension, and the full width at half amplitude of ¹⁷O-NMR. Further more, the analytical hierarchy process (AHP) was introduced to integrate the assessment of the effect of magnetic treatment on the cluster structure of water, and the integrated assessment index (IAI) was established to quantify the effect of magnetization on the liquid water. The viscosity of magnetic water increased with increasing the effective magnetic treatment time and had an amplification of approximately 10% when the effective magnetic treatment time was 13 minutes, and the internal energy of water decreased with increasing the effective magnetic treatment time. The surface tension and surface entropy of magnetic water decreased sharply with the the effective magnetic treatment time ranged from 1 minute to 13 minutes. The full width at half amplitude of ¹⁷O-NMR of purified water did not change when the effective magnetic treatment time was 1 minute but increased with an increasing the effective magnetic treatment time when the effective magnetic treatment time was higher than 1 minute, and the concentration of the hydrogen-bonded water increased. These results indicated that magnetic treatment promoted the formation of water clusters, and altered their distribution such that larger clusters were formed. This could be attributed to an increase in the intermolecular interactions of magnetic field treated water. In addition, according to the theory of AHP, an integrated model to assess the effect of magnetic treatment on the cluster structure of liquid water had been established as follows. The first step was to create a hierarchy model. To obtain the coincident magnitude of the indices, a normalizing method was applied to the indices (the internal energy, EI; surface entropy, SI; the free water ratio of liquid water, CI). The normalization method assumed all three indices of water to be 1 when the effective magnetic treatment time was maximum (13 minutes). The second step was to determine the pairwise comparison matrix for three indices. This problem involved a 3&times;3 reciprocal matrix, and the rule for determining pairwise comparison matrix had been summarized. The third step was the consistency measurement of the matrix just established. The fourth step was to calculate the weights of variables. According to the AHP theory, a normalized eigenvector corresponding to the maximum eigenvalue of the matrix just established will be the weight vector of the variables. The last step was to calculate the integrated assessment index (IAI). Therefore, the IAI value of magnetic water with any magnetization time can be calculated. The IAI values of the magnetic water increased linearly with increasing the effective magnetic treatment time, this result indicated that this method proposed a useful, reasonable, and acceptable method for the assessment of the effect of magnetic treatment on the cluster structure of water. The IAI values of magnetic water obtained by using the AHP are usefulness to study the application of magnetic water in the agriculture and water treatment.
Number of references:38
Main heading:Water treatment
Controlled terms:Agriculture - Eigenvalues and eigenfunctions - Entropy - Hierarchical systems - Hydrogen bonds - Liquids - Magnetic fields - Magnetization - Nuclear magnetic resonance - Surface tension  - Viscosity
Uncontrolled terms:Analytical Hierarchy Process - Cluster structure - Consistency measurement - Integrated assessment - Intermolecular interactions - Magnetic treatment - Normalization methods - Pairwise comparison matrices
Classification code:445.1 Water Treatment Techniques - 641.1 Thermodynamics - 701.2 Magnetism: Basic Concepts and Phenomena - 801.4 Physical Chemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921.1 Algebra - 931.2 Physical Properties of Gases, Liquids and Solids - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2014.21.035
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 31>

Accession number:20145100353355
Title:Design and experiment of automatic reseeding device for miss-seeding of crops with large grain
Authors:Zhu, Ruixiang (1); Ge, Shiqiang (1); Zhai, Changyuan (1); Yan, Xiaoli (1); Shi, Yanpeng (1); Li, Chengxin (1); Huang, Shanshan (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A&amp;F University, Yangling, China
Corresponding author:Zhai, Changyuan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:1-8
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The loss sowing phenomenon is common for sowers for crops with large grain. Reseeding and seed-metering devices now available are independent of each other. This method has some problems such as reseeding inaccurately. In order to solve these problems, an automatic reseeding method based on an overrunning clutch was proposed in this paper. An automatic reseeding device that was composed of both a reseeding device and a seed-metering device was designed. The device adopted a hall sensor to get the speed of the seed-metering device. The hall sensor got the time interval between every two seed spoons of the seed-metering device to calculate the real-time speed of the seed-metering device. A laser sensor was used to monitor the loss of seeds. Seeds in the plate of the seed-metering device could block the light propagation path of the laser. If the light propagation path of the laser was not blocked, the seed was lost. An overrunning clutch was used to connect a step motor and the axle of the seed-metering device. The step motor was used to drive the seed-metering device to reseed with high speed. The overrunning clutch is a kind of compound function bearing which transmits torque between the inside hub and outside hub in one direction and allows free overrun in the opposite direction. It was used to switch torque source between the wheels of the seed-metering device and the step motor. The torque source came from the wheels of the seed-metering device when seeding but from the step motor when reseeding. When the laser sensor monitored the loss of seeds, the controller calculated the rotational speed and angle of the step motor based on the real-time speed of seeding and position of the missing seeds. The step motor drove the seed-metering device to reseed with a higher speed than seeding speed. The subsequent seed was added to the vacant position quickly. The system of the automatic reseeding device would give failure warnings to the user if the seed-metering device has a breakdown. Experiments show that when the seeding speed is between 2 km/h and 5 km/h and the continuous missing seeds number is less than 3, the error of the reseeding time interval increases as the seeding speed and the continuous missing seeds number increase. However, the maximum relative error of the reseeding time interval is less than 1.37%. The automatic reseeding device has a good performance of reseeding timeliness. The failure warning system of the automatic reseeding device can warn users of the failure of the seed-metering device accurately. The accuracy of the failure warning is 100%. The qualified index of seeding space is 100%. The variation rate of seeding space is 14.48%. Both of the qualified index of seed space and the variation rate of seed space are much better than the performance indicators of precision seeders in Chinese standard. The reseeding accuracy of the automatic reseeding device is high. The average rate of successful reseeding is 92.98%, the comprehensive missing rate decreases to 0.8%, and the sowing rate increases to 99.2%. The automatic reseeding device has a good effect. The study can provide a reference to improve the design of the precise seeder for large grains.
Number of references:30
Main heading:Pneumatic materials handling equipment
Controlled terms:Agricultural machinery - Clutches - Crops - Design - Experiments - Grain (agricultural product) - Hall effect transducers - Light propagation - Machine design - Seed  - Speed - Stepping motors - Wheels
Uncontrolled terms:Auto-control - Chinese Standard - Maximum relative errors - Over running clutch - Performance indicators - Precision seeder - Seed-metering device - Unerring position reseeding
Classification code:408 Structural Design - 601 Mechanical Design - 601.2 Machine Components - 602.2 Mechanical Transmissions - 691.1 Materials Handling Equipment - 705.3 Electric Motors - 714 Electronic Components and Tubes - 741.1 Light/Optics - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.21.001
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 32>

Accession number:20145100353366
Title:Comprehensive regulation of agricultural water based on equilibrium of virtual water flow
Authors:Yan, Dong (1); Zhou, Jianzhong (1); Sun, Huaiwei (1); Wang, Xuemin (1)
Author affiliation:(1) College of Hydropower &amp; Information Engineering, Huazhong University of Science &amp; Technology, Wuhan , China
Corresponding author:Yan, Dong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:91-98
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To solve problems of lack of water resources for agriculture in arid areas, it is necessary to utilize and compare the advantage of water using in different areas that are linked together through the commodity trade. The active regulation of commodity trade and water consumption in production is capable to build rational virtual water use embodied in commodity trade. It will ease the conflict between water supply and demand. This requires the implement of integrated management about real water and virtual water to achieve regional equilibrium of virtual water utilization. Considering the water utilization should fit the scale of water resources endowment and economy, the equilibrium level based on Gini coefficient is used to evaluate the regional equilibrium of virtual water flow against water resources endowment and Gross Domestic Product. To improve the regional equilibrium, a comprehensive regulation model about agricultural water consumption was setup. The decision variables belonged to the aspects of water use efficiency, plant area of grain and yield level per unit area. Through the adjustment of the decision variable, the relevant equilibrium level can be calculated using a sub-model. In the sub-model, based on the equilibrium analysis of grain supply-demand, the grain flow direction and quantity were estimated using the optimization model for minimizing the total transportation costs. Combined with the agricultural water consumption per unit mass evaluation on every district, the amounts of virtual water flow among districts, and the total amounts of virtual water inflow and outflow of every district were setup. Then the equilibrium level about water resources endowment and Gross Domestic Product were calculated and became the output of the sub-model. To minimize the value of equilibrium level, the particle swarm optimization was used to search the non-inferior solutions about the combination of various decision variables. Then the final solution was selected in the non-inferior solutions. To test the performance of the method, a case study was made in Gansu Province in semi-arid Western China. The grain supply and demand, agricultural water consumption and water resources endowment of every county and city in Gausu province were estimated. They were the inputs of the comprehensive regulation model. The decision variables included planted areas, irrigation water amounts per unit area, and the yield per unit areas of wheat and corn in every district. The planted area can increase or reduce within a certain range, the irrigation water amounts per unit area and the yield per unit areas can only have a certain amount of reduction and growth respectively. The objective was that the agricultural water consumption in every district after regulation should not increase. The transportation of corn and wheat were railway and highway, and the specific means of transportation between every two districts was determined by the lowest cost per unit mass. By using the comprehensive regulation model, the non-inferior solutions gave the various combinations about decision variables. The grain areas, grain productions, water consumptions and virtual water flows in different solutions were quite different, but the equilibrium increased significantly comparing to that before regulation. In these solutions, the overall pattern about the virtual water flow in Gansu did not change a lot, and the virtual water import and export districts kept unchanged. The significant change emerged in the grain production and virtual water flows in some districts. The results showed that the agricultural water comprehensive regulation was capable to improve the equilibrium of virtual water matching the water cap, and can be a useful supplement to existing integrated water resources allocation methods. Further studies about the comprehensive regulation need to focus on the introduction about more realistic constraints, finer regulation mechanism and more accurate flow of grain trade.
Number of references:27
Main heading:Water resources
Controlled terms:Agriculture - Arid regions - Commerce - Cost benefit analysis - Decision making - Economics - Flow of water - Grain (agricultural product) - Hydraulics - Irrigation  - Mass transportation - Models - Particle swarm optimization (PSO) - Water supply
Uncontrolled terms:Comprehensive regulation - Gross domestic products - Integrated management - Means of transportations - Optimization modeling - Virtual water - Water resources allocations - Water supply and demands
Classification code:431.2 Passenger Air Transportation - 444 Water Resources - 446.1 Water Supply Systems - 631.1.1 Liquid Dynamics - 632.1 Hydraulics - 723 Computer Software, Data Handling and Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 902.1 Engineering Graphics - 911.2 Industrial Economics - 912.2 Management - 971 Social Sciences
DOI:10.3969/j.issn.1002-6819.2014.21.012
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 33>

Accession number:20145100353373
Title:Test on temperature characteristics of multi-spectral sensor for crop growth
Authors:Liu, Naisen (1); Ni, Jun (1); Dong, Jifei (1); Cao, Weixing (1); Yao, Xia (1); Tian, Yongchao (1); Zhu, Yan (1)
Author affiliation:(1) Jiangsu Key Laboratory for Information Agriculture, National Engineering and Technology Center for Information Agriculture, Nanjing Agriculture University, Nanjing , China; (2) Jiangsu Key Laboratory for Eco-Agricultural Biotechnology around Hongze Lake, Huaiyin Normal University, Huai'an , China
Corresponding author:Zhu, Yan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:157-164
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In modern agriculture, the application of non-destructive spectroscopic techniques is very useful for estimating crop growth status. Non-destructive monitoring techniques based on spectral reflectance can provide the real-time information required for crop growth regulation. Thus, these techniques have significant application value in crop production. Despite being highly precise, the existing non-destructive spectroscopic techniques such as FieldSpec Pro FR250, GreenSeeker, and Crop Circle ACS-470 are expensive and complicated, hence their application is not suitable for agricultural production especially in China where the average per capita landholding is about 0.1 ha. In order to promote the use of non-destructive monitoring spectrum technology in agriculture, the National Engineering and Technology Center for Information Agriculture, Nanjing Agricultural University has developed a multi-spectral sensor for crop growth monitoring. The sensor monitor has a spectral reflectance of 720 nm and 810 nm to access growth indexes of leaf nitrogen content (LNC), leaf nitrogen accumulation (LNA), leaf area index (LAI), and plant dry matter (PDM). Under field conditions, the seasonal variations in temperature and sunlight can affect the internal temperature of the sensors from 10 to 60. Temperature compensation is required to minimize the impacts of internal variations in temperature on the output signal of the sensor. Hardware compensation and software compensation are the two methods of temperature compensation. Hardware compensation methods mainly use electric circuits such as the thermal bridge compensation method and the double electric bridge compensation method to eliminate the influence of temperature. However, these methods are complex, expensive, and have low accuracy. Software compensation methods eliminate the influence of temperature on sensors by building a temperature compensation model, such as an interpolation method, least squares polynomial curve fitting method, least squares support vector machine method, or artificial neural network method, etc. The software compensation methods are simple, cheap, and have high accuracy as compared to hardware compensation methods. A temperature compensation model for reflectivity was constructed by studying the effect of temperature on the sensors in order to improve the temperature stability of the sensor for field applications. The experiments were carried out in a temperature and humidity control chamber. In experiment 1, the experiment temperature was set to 6, 11, 15, 20, 25, 30, 35, 40, 44, 49, 54, and 62. and 40% relative humidity was maintained. Under constant light intensity, a standard gray board with 40% reflectivity was used as the monitoring object of the sensor. Experiment 2 was carried out under the same experimental temperature conditions as that in experiment 1. However, the light intensity was changed, and 40% and 60% reflectance standard gray boards were used as the monitoring object of the sensor to examine the suitability of a newly constructed temperature compensation model for the reflectivity. The results indicated that under constant light intensity, the sensor output voltage increases while the reflectance decreases with an increases in temperature. A temperature-based sensor output voltage prediction model with the coefficient of determination R² was 0.9998, and relative root mean square error RRMSE of 2.31% was constructed to predict sensor output voltage at different temperatures on the basis of output voltage at 25. The transformed prediction model in the present study can obtain 25 sensor output voltage according to the output voltages at different temperatures. The temperature compensation of reflectance was well implemented by using the 25 output voltage obtained by the transformed model to calculate reflectance. After temperature compensation, the reflectance fluctuation range decreased, and the max range was less than 0.45%. The t test results (P=0.015&lt;0.05) showed that a temperature compensating model could significantly reduce the effect of temperature on the reflectivity.
Number of references:35
Main heading:Least squares approximations
Controlled terms:Agricultural machinery - Bridge circuits - Complex networks - Crops - Cultivation - Curve fitting - Experiments - Forecasting - Hardware - Humidity control  - Low noise amplifiers - Mathematical models - Mean square error - Monitoring - Neural networks - Nitrogen - Polynomial approximation - Reflection - Sensors - Temperature  - Temperature distribution - Two phase flow
Uncontrolled terms:Artificial neural network methods - Coefficient of determination - Crop growth - Least squares support vector machines - Non-destructive monitoring - Polynomial curve fitting methods - Temperature and humidity control - Temperature compensation
Classification code:402 Buildings and Towers - 605 Small Tools and Hardware - 631.1 Fluid Flow, General - 641.1 Thermodynamics - 703.1 Electric Networks - 711 Electromagnetic Waves - 716 Telecommunication; Radar, Radio and Television - 722 Computer Systems and Equipment - 723.4 Artificial Intelligence - 731.1 Control Systems - 801 Chemistry - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research - 921 Mathematics - 921.6 Numerical Methods - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.21.019
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 34>

Accession number:20145100353371
Title:Effect of climatic factors such as temperature, precipitation on maize production in China
Authors:Wang, Liu (1); Xiong, Wei (2); Wen, Xiaole (3); Feng, Lingzhi (2)
Author affiliation:(1) Editorial Department of the Transactions of the Chinese Society of Agricultural Engineering, Chinese Society of Agricultural Engineering, Chinese Academy of Agricultural Engineering, Beijing , China; (2) Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, Beijing , China; (3) College of Environment and Resources, Fuzhou University, Fuzhou , China
Corresponding author:Xiong, Wei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:138-146
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Impacts of climate change on agriculture has received wide concerns globally, yet a number of questions such as how past climate change affected the crop yields, which climatic variables were the main contributor for observed yield reduction remained unanswered to date, particularly in developing countries. Information about the climatic risks posed on crop growth, and yield responses to the specific climatic risks is prerequisite for understanding the underlying mechanisms of climate change impacts and devising appropriate adaptation strategies. This study first identified the changes of growing-season climatic variables (temperature, precipitation, and solar radiation) from 1982-2006 for China's maize production. Using the relationships between changes in survey maize yield and climatic variables and their spatial variations, we investigated and untangled the impacts of different climatic variables on maize yield. Our analysis demonstrated that the growing-season temperatures, including daily maximum, minimum and mean temperatures, exhibited significant increase during 1981-2006, indicating the potential climatic risks for maize growth in China. Growing-season diurnal temperature range, precipitation and solar radiation also exhibited detectable changes, but limited to small parts of the maize area. During 1981-2006, there were significant negative correlations between national maize yield and temperatures (include mean, maximum, and minimum temperatures). Maize yield in some maize areas also exhibited linear correlation relationship to growing-season diurnal temperature range, solar radiation, and precipitation. With a 1 warming in growing-season temperature, 1 increase in diurnal temperature range, a 10% decrease in radiation and precipitation, much of the maize area showed detectable yield response to these changes. Maize experienced depressed yield to the 1 warming in growing-season temperature, denoting by roughly a quarter of China's maize area exhibiting depressed yield and an estimated reduction of 25.1% across the regions that have detectable negative yield responses. The four climatic variables have diverse impacts on the maize yield in terms of the magnitude of yield change and the spatial variation of yield response. We identified the key climatic factor for observed maize yield change for all maize area. Temperature appeared as the first key climatic driver for maize yield change in over 40% maize area, while diurnal temperature range acted as a main player in 23% maize area. Radiation and precipitation shared a small and similar portion of maize area for playing as the key climatic variables for the yield response. We recognized the uncertainties in our study some of which came from reliability of data resource and the use of statistical method. However, this study provided first hand information on maize yield response to historical climatic risks, which advanced the understanding of underlying mechanism of climate change impacts on China's maize production and assisted the projection of maize yield for future climate change.
Number of references:27
Main heading:Climate change
Controlled terms:Crops - Developing countries - Heat radiation - Precipitation (chemical) - Risk assessment - Solar radiation - Sun - Temperature
Uncontrolled terms:Adaptation strategies - Climate change impact - Diurnal temperature ranges - Linear correlation - Maize - Minimum temperatures - Negative correlation - Yield
Classification code:451 Air Pollution - 641.1 Thermodynamics - 641.2 Heat Transfer - 657.1 Solar Energy and Phenomena - 657.2 Extraterrestrial Physics and Stellar Phenomena - 802.3 Chemical Operations - 821.4 Agricultural Products - 901.4 Impact of Technology on Society - 922.1 Probability Theory
DOI:10.3969/j.issn.1002-6819.2014.21.017
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 35>

Accession number:20145100353362
Title:Test on combustion stability of small-sized biomass gas engine
Authors:Chen, Lei (1); Song, Peng (2); Long, Wuqiang (2); Fu, Yao (2); Zeng, Wen (1)
Author affiliation:(1) Liaoning Key Laboratory of Advanced Measurement and Test Technology for Aviation Propulsion System, Shenyang Aerospace University, Shenyang , China; (2) Institute of Internal Combustion Engine, Dalian University of Technology, Dalian, China; (3) College of Electromechanical &amp; Information Engineering, Dalian Nationalities University, Dalian, China
Corresponding author:Chen, Lei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:55-62
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The experimental researches of engine operation stability were carried out based on a small-sized spark ignition engine fueled with simulated biogas, which includes hydrogen, CH<inf>4</inf>, and carbon dioxide. The influences of equivalence ratio, H<inf>2</inf> concentration and CO<inf>2</inf> concentration on combustion stability were investigated under wide opening throttle valve (WOT) and maximum brake torque (MBT) conditions. The results showed that engine operation stability was strongly influenced by fuel composition. Under low H<inf>2</inf> concentration conditions, CO<inf>2</inf> concentration played a dominant effect on combustion stability, and its increasing could induce the increase in cyclic variation and the occurrence of partial burn. However, under high H<inf>2</inf> concentration, the effect of CO<inf>2</inf> concentration on combustion gradually weakened. By adjusting fuel composition, the operation stability of biogas engines can be improved.
Number of references:22
Main heading:Carbon dioxide
Controlled terms:Atmospheric composition - Biogas - Biomass - Carbon - Carbon monoxide - Combustion - Combustion equipment - Composting - Energy resources - Engines  - Experiments - Fluidization - Fluidized bed combustion - Fluidized bed process - Fluidized beds - Fuels - Gasification - Hydrogen - Inert gases - Internal combustion engines  - Mixtures - Stability - Temperature
Uncontrolled terms:Combustion temperatures - Combustion velocities - Cyclic variations - Design and construction - Experimental research - Individual components - Maximum brake torques - Temperature conditions
Classification code:452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 521.1 Fuel Combustion - 521.2 Combustors - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 525.1 Energy Resources and Renewable Energy Issues - 533.1 Ore Treatment - 612 Engines - 612.1 Internal Combustion Engines, General - 641.1 Thermodynamics - 801 Chemistry - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 901.3 Engineering Research - 931 Classical Physics; Quantum Theory; Relativity - 951 Materials Science - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2014.21.008
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 36>

Accession number:20145100353374
Title:Extraction of crop planting structure in seasons prone to waterlogging using Landsat8 OLI and MODIS data
Authors:Chen, Yingshu (1); Zhang, Xiaochun (1); Wang, Xiugui (1); Luo, Qiang (1); Xiong, Qinxue (2); Luo, Wenbing (1)
Author affiliation:(1) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan , China; (2) College of Agriculture, Yangtze University, Jingzhou , China
Corresponding author:Zhang, Xiaochun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:165-173
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Flood disaster occurs frequently in China and brings severe disaster to crops. Therefore, the crop plant structure in seasons prone to waterlogging becomes significant information for studies on flood loss, flood control, and disaster mitigation. Under these conditions, this paper presents a fast and convenient method to extract the crop plant structure in small scale areas during seasons prone to waterlogging, based on multi-sensor and multi-temporal remote sensing data. Landsat8 OLI and MODIS data were chosen because of the advantages such as it being free of charge and easy to search for and download. These two types of data showed the characteristics of crops' growth respectively in space and time, leading to a proper combination for crop planting structure extraction. If one only uses MODIS data to build the extraction model, the spatial resolution is too low to get the planting structure in small scale areas. On the other hand, just classifying the OLI images by visual interpretation sometimes could not determine the types of crops. The Jianli County in Jingzhou City, Hubei Province was chosen as the study area. The seasons prone to waterlogging in Jianli mainly include June, July, and August, and are related to crops such as early-season rice, middle-season rice, late rice, and cotton. Here are the extracting models for the four major kinds of crops: NDVI value of cotton grows to the peak in early July and stays high until September; early-season rice NDVI maximum value appears in middle June, and it becomes completely mature in late July; middle-rice NDVI value starts to increase at the end of May and reaches its peak in early or middle July before falling to a decline; NDVI value of late rice goes up in mid-July and the peak value appears in middle or late August, and then the value begins to decline. First, a time series curve of NDVI was built from the MODIS data, which was later smoothed by an improved Savitzky-Golay filter. The improved Savitzky-Golay filter reserved the authenticity of data at both ends of the NDVI time series while further improving the smoothness of the curve. To distinguish the types of crops, threshold values of NDVI for different crops were set according to corresponding phenophases. Based on the characteristics and threshold values of NDVI time series, appropriate ROIs (Region of Interest) in the Landsat8 OLI images in key growth stages of different crops were selected as prior knowledge for training. Finally, the area and distribution of the four studied crops were extracted by a BP Neural Net Supervised Classification. The experimental results agreed well with the statistical data and a ZY-3 image which had a spatial definition of 6 meters, and obtained an average precision above 90%. It was concluded that the proposed method in this paper is simple and easy operating. Moreover, it accurately reflected the real situation of crop distribution in the Jianli area, and is suited for extraction of the plant structure in small scale areas like Jianli. Therefore, this method provides a reliable basis for related research studies on flood disaster.
Number of references:35
Main heading:Crops
Controlled terms:Cotton - Disasters - Extraction - Flood control - Flood damage - Image reconstruction - Image segmentation - Radiometers - Remote sensing - Satellite imagery  - Space optics - Time series
Uncontrolled terms:Crop plants - Moderate resolution imaging spectroradiometer - Multi-temporal remote sensing - Operational land imager - Savitzky-Golay filter - Seasons prone to waterlogging - Supervised classification - Visual interpretation
Classification code:406 Highway Engineering - 443 Meteorology - 454.1 Environmental Engineering, General - 484 Seismology - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 741.1 Light/Optics - 802.3 Chemical Operations - 821.4 Agricultural Products - 922.2 Mathematical Statistics - 944.7 Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.21.020
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 37>

Accession number:20145100353370
Title:Drought monitoring of upper and middle reaches of Qingjiang Basin based on SWAT model
Authors:Sun, Li (1); Chen, Xiwei (1); Pei, Zhiyuan (1)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing , China
Corresponding author:Sun, Li
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:129-137
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years droughts occurred frequently in western, southwestern remote mountainous areas of China, affecting the local agricultural production and farmers' life. Drought monitoring and prediction is one of the main tasks of crop condition monitoring. Remote sensing data and ground survey data are used to monitor drought in current crop condition monitoring system, while high-resolution Remote sensing data and enough ground survey data for effective monitoring are often unable to access timely in those remote mountainous areas due to complex topography and broken plots. The aim of the study was to develop drought monitoring method to meet the complex terrain area and then to provide reliable scientific information to guide agricultural production. Crop water deficit index (CWDI) as an index characterizing agricultural drought has been widely used, which includes parameters of potential evapotranspiration (PET) and precipitation. Soil and water assessment tool (SWAT) as a distributed hydrological model with strong mechanism has been used to simulate crop's potential evapotranspiration in those areas with complex topography. Those tools provide a feasible way of this study. The upper and middle reaches of Qingjiang River Basin, as the study area, from which drought conditions were monitored by the combination of CWDI and SWAT. Land use/cover data, soil data, topography data, meteorology data and hydrological data from 2003 to 2005 and 2007 to 2010 were used for calibration and validation of SWAT model. The PET simulated by SWAT had a high correlation fit with the PET calculated with meteorological data. Comparison of the statistical indexes included relative bias, root mean square error and multiple correlation coefficients. Standard precipitation index (SPI) was used for two times of drought monitoring tests to compare with the crop water deficit index (CWDI) based on the SWAT model. In July 2009, heavy drought happened in upper and middle reaches of Qingjiang River Basin. From the result of SPI, most part of the area had severe drought including Lichuan, Jianshi and Hefeng. Based on statistics of GIS software, severe drought area was about 86,830 ha. There was a different range of severe drought in Lichuan, Enshi, Jianshi, Badong and Xuanen from the result of CWDI. The area of severe drought was 23,059 ha. However, based on the regional survey, due to continuous high temperatures and less precipitation, crop growth was affected and about 25,440 ha of farmland was heavily affected. In April 2010, light drought was taken place in upper and middle reaches of Qingjiang River Basin. From the result of SPI, only mild drought happened in Enshi, Badong and Jianshi and there was no other level of drought for the same time period. The monitoring result of CWDI showed that moderate drought occurred in part of Enshi region and mild drought in north-central of Jianshi, north of Badong. There was about 7,448 ha of moderate drought from the statistical survey result. According to the statistical survey data,the affected area of crop reached 8,000 ha. Compared with the monitoring results of SPI, the disaster degree and scope were closer between CWDI and actual survey results. The difference existed in these two kinds of monitoring results, which mainly because SPI consisted of precipitation without other elements, which can not objectively reflect the degree of water demand of land surface. CWDI was composed by PET and precipitation and PET was a function of many meteorological elements and crop factor, which can reflect different situation under the same precipitation. The results proved that the combination of CWDI and SWAT can reflect the regional drought condition objectively at the period of crop growth in mountainous areas and overcome the limitations of meteorological drought index calculated by few meteorological stations' data.
Number of references:29
Main heading:Drought
Controlled terms:Condition monitoring - Crops - Disasters - Evapotranspiration - Geographic information systems - Land use - Mean square error - Meteorology - Monitoring - Remote sensing  - Rivers - Soils - Surveys - Topography - Watersheds
Uncontrolled terms:Distributed hydrological model - High resolution remote sensing - Multiple correlation coefficients - Potential evapotranspiration - Soil and water assessment tool - Soil and Water assessment tools - Standard precipitation indices - Water deficit index
Classification code:403 Urban and Regional Planning and Development - 405.3 Surveying - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 483.1 Soils and Soil Mechanics - 484 Seismology - 603 Machine Tools - 706 Electric Transmission and Distribution - 723.3 Database Systems - 731.1 Control Systems - 821.4 Agricultural Products - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.21.016
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 38>

Accession number:20145100353382
Title:Biochar input to reduce trace greenhouse gas emission in paddy field
Authors:Li, Song (1); Li, Haili (2); Fang, Xiaobo (2); Shi, Huixiang (1)
Author affiliation:(1) College of Environmental and Resources Sciences, Zhejiang University, Hangzhou , China; (2) School of Environmental and Resource Sciences, Zhejiang Agriculture and Forestry University, Hangzhou , China
Corresponding author:Li, Song
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:234-240
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Biochar application to the paddy field may be an effective method to deal with global climate change for the mankind. The effect of four different application rates of biochar made from bamboo added to the paddy field on soil quality, rice yield and trace greenhouse gas emissions was investigated by a field experiment to provide a scientific basis for biochar agricultural application. The experiment was carried out in a rice farm from Tai Lake Region and consisted of four treatments, biochar at 10 t/hm² (T1), biochar at 20 t/hm² (T2), biochar at 40 t/hm² (T3), and paddy field without biochar application as a control (T0). Each treatment had three replicates arranged in a completely randomized block design. Changes in soil chemical and physical properties, rice yield and trace greenhouse gases (CH<inf>4</inf>, N<inf>2</inf>O) emissions with biochar addition were investigated during a whole rice growing season of 2013. The results showed that, comparing with the control treatment, soil pH value and organic carbon content were significantly increased (P&lt;0.05) after biochar application, and the increase of organic carbon content was proportional to biochar application amount (r=0.78, P&lt;0.01). Soil bulk density was significantly decreased with the increasing biochar application rate (P&lt;0.05). Biochar application had no significant effect on soil cation exchange capacity, total nitrogen, available phosphorus and quick-acting potassium content (P&gt;0.05). Rice yields of four treatments were respectively (8 120.6&plusmn;468.2), (8 313.5&plusmn;221.8), (8 505.4&plusmn;381.2) and (7 996.8&plusmn;285.6) kg/hm², and had no significant difference with biochar application amount (P&gt;0.05), and the same result was obtained by the experiment of 2014, which showed biochar application cannot increase rice yield effectively, but can stable rice yield sustainably. CH<inf>4</inf> emission flux decreased gradually with the increase of biochar application amount. Meanwhile, CH<inf>4</inf> cumulative emission decreased effectively with biochar application. There was a negative correlation between CH<inf>4</inf> cumulative emission and biochar application amount (r=-0.24, P&lt;0.01).However, CH<inf>4</inf> cumulative emission cannot decrease significantly by excessive biochar application (P&gt;0.05). Comparing with the control (T0), N<inf>2</inf>O emission flux decreased significantly within a week after biochar application (P&lt;0.05), and rose slightly during the drainage of the paddy field, and finally reached a steady value (about 9.80 mg/(m²&middot;h)) for three biochar application treatments (T1, T2 and T3). However, there was no significant difference with CH<inf>4</inf> cumulative emission between the treatments of biochar at 20 t/hm² (T2) and 40 t/hm² (T3) (P&gt;0.05), implying that CH<inf>4</inf> cumulative emission cannot decrease effectively by excessive biochar application (&gt;20 t/hm² for the purple clay soil in the Tai Lake region). N<inf>2</inf>O cumulative emission decreased significantly with biochar application (P&lt;0.05), but there was no significant difference among the treatments with different biochar application rates (P&gt;0.05). CH<inf>4</inf> and N<inf>2</inf>O emission fluxes and cumulative emissions showed the similar changes according to the preliminary experiment results of 2014. In this experiment, considering the effect and cost comprehensively, biochar application amount at 20 t/hm² could be a technical option to reach low carbon emission intensity and stable rice producitivity in the rice paddy agriculture. It also provided a viable way to realize the enhancement of carbon sequestration and the mitigation of greenhouse emissions in the Tiaoxi Watershed of Tai Lake region.
Number of references:30
Main heading:Experiments
Controlled terms:Agriculture - Bamboo - Biomass - Carbon - Clay - Gas emissions - Greenhouse effect - Greenhouse gases - Lakes - Methane  - Nitrogen oxides - Organic carbon - Soils
Uncontrolled terms:Bamboo carbons - Bio chars - Emission fluxes - Nitrous oxide - Paddy soils
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 451 Air Pollution - 451.1 Air Pollution Sources - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901.3 Engineering Research
DOI:10.3969/j.issn.1002-6819.2014.21.028
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 39>

Accession number:20145100353364
Title:Irrigation and fertilization coupling of drip irrigation under plastic film promotes tomato's nutrient uptake and growth
Authors:Xing, Yingying (1); Zhang, Fucang (1); Zhang, Yan (1); Li, Jing (1); Qiang, Shengcai (1); Li, Zhijun (1); Gao, Mingxia (1)
Author affiliation:(1) College of Water Resources and Architectural Engineering, Northwest A&amp;F University, Yangling , China; (2) Key Laboratory of Agricultural Soil and Water Engineering in Arid and Semiarid Areas of Ministry of Education, Northwest A&amp;F University, Yangling , China; (3) Institute of Water-saving Agriculture in Arid Areas of China, Northwest A&amp;F University, Yangling , China
Corresponding author:Zhang, Fucang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:70-80
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The low irrigation and fertilizer use efficiency of the greenhouse vegetables is a serious problem in semi-arid northwest areas of China. The purpose of this study was to investigate the effect of fertigation on tomato growth, yield, nutrient absorption and utilization efficiency in a solar greenhouse, thereby providing a theoretical and experimental basis for the irrigation and fertilizer management of tomato greenhouse in this area. From March to July 2013, the plot experiments were carried out on a greenhouse tomato cultivar of Jinpeng 10 at Yangling District of Shaanxi Province. Two factors of irrigation (W) and fertilizer (F: N-P<inf>2</inf>O<inf>5</inf>-K<inf>2</inf>O) were set up in this study. There were 3 irrigation levels (W1:100%ET<inf>0</inf>; W2:75%ET<inf>0</inf>; W3:50%ET<inf>0</inf>, ET<inf>0</inf> is the reference crop evapotranspiration), 3 fertilizer levels (N:P<inf>2</inf>O<inf>5</inf>:K<inf>2</inf>O in F1: 240: 120: 150 kg/hm², F2: 180: 90: 112.5 kg/hm², F3: 120: 60: 75 kg/hm²), and a control treatment irrigated by conventional furrow method (W: 100%ET<inf>0</inf>, N:P<inf>2</inf>O<inf>5</inf>:K<inf>2</inf>O was 240: 120: 150 kg/hm²). The results showed that the dry matter accumulation, tomato yield and partial factor productivity of fertilizer for the drip fertigation treatment (W1F1) were 144.77 kg/hm², 97.15 t/hm² and 190.5 kg/kg, respectively, which were 60.0%, 46.9% and 47.0% higher than those of the control treatment with the same amount of irrigation and fertilizer. The absorptive amount of nitrogen, phosphorus and potassium in the plant organs were 1.82-2.41, 1.56-2.03, and 1.36-1.90 times higher than those of the control treatment, respectively. Except for the harvest period, the distribution rates of nitrogen, phosphorus and potassium in fruits were greater than those of the control treatment. The drip fertigation treatment also significantly increased the absorption efficiency of nitrogen, phosphorus and potassium as well as the partial factor productivity of fertilizer (PFP). Under drip irrigation and fertilization condition, the dry matter accumulation increased with the increase of irrigation water. Under the irrigation treatments W1 and W2, the dry matter accumulation first increased and then decreased as the fertilizer increased, while it continuously increased with the increase of the fertilizer under the treatment W3. The maximum dry matter accumulation was recorded in the W1F2 treatment (9 258.3 kg/hm²). Tomato yield was significantly affected by the irrigation, fertilization and irrigation-fertilization interaction, increased with the increase of irrigation water and fertilizer. The maximum tomato yield was recorded in the W1F1 treatment (97.15 t/hm²). Tomato yield in the W1 and W2 treatments were 19.0% and 6.5% higher than that of the W3 treatment, while the tomato yield in the F1 and F2 treatments were 18.3% and 12.9% higher than that of the F3 treatment. The absorptive amount of nitrogen, phosphorus and potassium increased with the increase of irrigation and fertilization amount except for the second fruit enlargement period, when the maximum absorptive amount of phosphorus and potassium were recorded in the F2 treatment. With the advance of the growth period, the difference of nutrient uptake under the F2 and F3 treatments increased, while the difference decreased compared to the F1 treatment. The amount of irrigation and fertilizer significantly affected the absorption and use efficiency of nitrogen and phosphorus, the use efficiency of potassium, and the PFP. The irrigation-fertilizer interaction significantly affected the PFP, but it exerted no significant interaction effects on the nutrient use efficiency (NUE) and the nutrient uptake efficiency (UPE). The higher the irrigation amount was used, the smaller the NUE was, but the higher the UPE and the PFP were. The higher the fertilizer amount was used, the smaller the NUE, UPE and PFP were. The results indicated that fertigation treatment obviously increased the tomato yield. With the highest dry matter accumulation, higher nutrient uptake efficiency and partial factor productivity of fertilizer, the W1F2 (100%ET<inf>0</inf>, N:P<inf>2</inf>O<inf>5</inf>:K<inf>2</inf>O was 180:90:112.5 kg/hm²) treatment was recommended as an appropriate schedule for irrigation and fertilization due to its high yield-increasing potential.
Number of references:25
Main heading:Irrigation
Controlled terms:Efficiency - Fertilizers - Film growth - Forestry - Fruits - Greenhouse effect - Greenhouses - Nitrogen - Nitrogen fertilizers - Nutrients  - Phosphorus - Potassium - Productivity - Water - Water absorption - Water supply
Uncontrolled terms:Distribution - Fertilizer use - Nutrient absorption - Tomato - Yield
Classification code:444 Water Resources - 446.1 Water Supply Systems - 451 Air Pollution - 549.1 Alkali Metals - 712.1 Semiconducting Materials - 802.3 Chemical Operations - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2014.21.010
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 40>

Accession number:20145100353387
Title:Estimation on farmland soil loss by single wind erosion using improved particle-size distribution comparison method
Authors:Wang, Rende (1); Xiao, Dengpan (1); Chang, Chunping (2); Guo, Zhongling (2)
Author affiliation:(1) Institute of Geographical Sciences, Hebei Academy of Sciences, Hebei Engineering Research Center for Geographic Information Application, Shijiazhaung , China; (2) College of Resource and Environment Sciences, Hebei Key Laboratory of Environmental Change and Ecological Construction, Hebei Normal University, Shijiazhang , China
Corresponding author:Wang, Rende
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:21
Issue date:November 1, 2014
Publication year:2014
Pages:278-285
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Estimations were performed using improved particle-size distribution comparison method for the severe wind-erosion event in 2014 for the principal farmland types in the Bashang area of Hebei Province. The results showed that the soil loss of farmland by wind erosion in the severe wind-erosion event was 0.35&times;10⁶-4.11&times;10⁶ kg/km², average wind erosion was 1.30&times;10⁶ kg/km², and the average depth of wind erosion was 0.09 cm. In the two farmland types, the soil loss by wind erosion of ploughed and raked fields during this event was 0.85&times;10⁶-4.11&times;10⁶ kg/km² with an average of 2.00&times;10⁶ kg/km², and the soil loss by wind erosion of fields of oat stubble was 0.35&times;10⁶-1.50&times;10⁶ kg/km² with an average of 0.70&times;10⁶ kg/km². The soil loss by wind erosion on fields of oat stubble was clearly less than on ploughed and raked fields (i.e., only 35.11%). Therefore, the presence of stubble can be seen as an effective measure against the erosion of farmland by wind. The soil loss by wind erosion at the different sampling sites varies considerably in this wind-erosion event. In the ploughed and raked fields, the soil loss by wind erosion at sampling site 1 was the largest (4.11&times;10⁶ kg/km²), followed by sampling site 2 (1.66&times;10⁶ kg/km²). Sampling site 3 shows the minimum soil loss by wind erosion (0.85&times;10⁶ kg/km²), which was only 20.76% of that at sampling site 1. In the fields of oat stubble, the soil loss by wind erosion at sampling site 1 was the largest (1.50&times;10⁶ kg/km²), followed by sampling point 4 (0.54&times;10⁶ kg/km²). The soil loss by wind erosion at sampling point 2 was the minimum (0.35&times;10⁶ kg/km²), which was equal to 23.12% of that at sampling site 1.
Number of references:17
Main heading:Erosion
Controlled terms:Estimation - Farms - Light transmission - Particle size - Particle size analysis - Size distribution - Soils - Wind tunnels
Uncontrolled terms:Cumulative amount - Distribution comparisons - Effective measures - Field observations - Hebei Province - Sampling points - Wind erosions - Wind-tunnel simulation
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 423 Non Mechanical Properties and Tests of Building Materials - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 651.2 Wind Tunnels - 741.1 Light/Optics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 943.2 Mechanical Variables Measurements - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.21.033
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.