<RECORD 1>

Accession number:20132516429417
Title:Design of food digital ID and its application in electronic receipt of wine logistics
Authors:Luo, Aimin (1); Yi, Bin (2); Shen, Caihong (2)
Author affiliation:(1) Light Industry, Textile and Food Engineering College, Sichuan University, Chengdu 610065, China; (2) Luzhou Lao Jiao Co., Ltd, Luzhou 646600, China
Corresponding author:Shen, C.(599159632@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:262-268
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Food quality traceability system is of great significance for ensuring food safety. A reliable traceability system based on radio frequency identification devices (RFID) is proposed in this paper. Specific requirements of the food digital ID are analyzed, and six requirements of communications security, system availability, data authenticity, information privacy, data authority, traceability are listed. An asymmetric encryption algorithm NTRU and a digital signature algorithm based on NTRU are developed to design secure authentication protocol and food digital ID. Firstly the public key, private key and digital certificate of all nodes in the supply chain are issued by a trusted third-party certification authority, correspondingly the RFID tag's ID of the node is recorded and the encrypted product information is written to the RFID tag, thus creating a digital ID. Then the certification process among the nodes using the digital ID is demonstrated in detail. The node's reader generates a random number R and Q, and transmits to tags, where Q is the encrypted data with result of XOR operation of R and reader's serial number K using its private key by NTRU. After receiving the Q and R, the tags decrypt and calculate K with a corresponding reader's public key. If the K is one of the reader's serial number stored in RFID tag, it is accepted to the next communication, otherwise is denied to the next communication. After successful authentication, the tag calculates M and transmits to reader, where M is the encrypted data with result of XOR operation of R and tag's ID using the reader's public key by NTRU. After received the M, the reader decrypts and calculates tag's ID with its private key. If the tag's ID is one of the tag's ID stored in reader, the reader accepts the next communication, otherwise denies the next communication. Through these steps, the reader and the tag establish a trusted channel to read or write. Finally, the security is discussed and well fit with the safety requirements of the food digital ID, thus the food digital ID is accomplished. With secure authentication protocol, electronic receipt of wine logistics using the food digital ID is achieved. With the electronic receipt of wine logistics, the four roles of manufacturers, sales, consumers, certification centers are designed, the four procedures of registration and certification, information of manufacturer written to the tag, information of vendors written to the tag, consumers verification are developed. The application prototype system is built in wine logistics, fundamentally improving the security and reliability of wine logistics according to analysis of its security. Food digital ID and electronic receipt of wine logistics are proposed in this paper, the work will be of great interest for use in safe and reliable supervision and management for food quality.
Number of references:31
Main heading:Wine
Controlled terms:Access control - Communication - Cryptography - Food products - Information management - Manufacture - Quality assurance - Radio frequency identification (RFID) - Reliability analysis - Supply chains
Uncontrolled terms:Asymmetric encryption - Communications security - Digital id - Digital signature algorithms - Electronic receipts - Radio frequency identification devices - Secure authentications - Security and reliabilities
Classification code:913 Production Planning and Control; Manufacturing - 912.2 Management - 912 Industrial Engineering and Management - 822.3 Food Products - 723 Computer Software, Data Handling and Applications - 716.3 Radio Systems and Equipment - 716 Telecommunication; Radar, Radio and Television
DOI:10.3969/j.issn.1002-6819.2013.10.035
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 2>

Accession number:20132516429386
Title:Power consumption and parameter optimization of stalk impeller blowers
Authors:Zhai, Zhiping (1); Gao, Bo (1); Yang, Zhongyi (1); Wu, Yamei (2)
Author affiliation:(1) College of Mechanical Engineering, Inner Mongolia University of Technology, Huhhot 010051, China; (2) Huhhot Branch of Chinese Academy of Agricultural Mechanization Sciences, Huhhot 010020, China
Corresponding author:Zhai, Z.(ngdzhaizhiping@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:26-33
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The impeller blower is widely used in various forage harvesters, such as crop straw choppers, rubbing, and breaking machines, to convey materials because of its simplicity, reliability, easy maintenance and adjustment, high capacity and low manufacturing cost. However, some undesired problems such as high power consumption, low throwing/blowing efficiency and high clogging probability also exist in the process of throwing/blowing the materials. In order to reduce the power consumption of the impeller blower and increase its blowing efficiency, the theoretical analyzing method was used to establish the mathematical models of the power consumption, firstly based on considering the airflow, which is suitable for forward-slant, backward-slant and radial paddle. The power consumption includes two parts. One part is the energy required to accelerate the materials that will obtain kinetic energy by means of the mechanical centrifugal force when the paddle rotates at high speed. The other part is the energy that accelerates the airflow in the impeller blower and helps the materials conveying under the condition of high rotating speed of the paddle. The first power consumption is related to the material-threw angle, namely, the rotation angle of the paddle in the course of hitting, carrying and throwing out of the material. When the material-threw angle is in the range from approximately 60&deg;to 130&deg;, all materials are thrown out of the housing under the condition of low energy consumption, high throwing/blowing efficiency and low clogging probability. However, when the material-threw angle is less than 60&deg; or more than 130&deg;, few materials are thrown out of the housing directly. Most of the materials will hit the housing, which causes most of the energy lost under the hitting energy E4c and a frictional energy E4f. Through validation by using the test data of the corn stalk, it shows that the computing power consumption by using this mathematical model of the power consumption agrees well with the measured data by multiplying the E4c and E4f with a correction factor of k=0.35 respectively. Moreover, the optimum design was conducted to the structural and kinematic parameters of the impeller blower by treating the minimum specific power consumption (energy consumption of unit throughput) as the target function by using a Virtual Prototype Technology based on a modified ADAMS model of materials motion along the paddles in reference paper. The results show that when the impeller's external diameter is 700mm, its width is 160mm, its rotational speed is in the range of 650-2000r/min, the forward slant angle changes from -25&deg; to 0 (radial paddle) and the backward slant angle changes from 5&deg; to 25&deg; with an increasing step of 5&deg;, the radial paddle with a rotational speed of 650r/min consumes the minimum specific power. As is shown from the comparative analysis of the real specific power consumption and the optimized results, the optimum results are reliable. Furthermore, the optimum parameter setup for the impeller blower is gained at different operating conditions by using a parametric analysis of a Virtual Prototype Technology. For example, when the impeller blower works with the rubbing and breaking machine and throws/blows the rubbed and broken materials, and the impeller's external diameter is 700 mm, its width is 160 mm, its rotational speed is 1550r/min and the feeding quantity is 1.8 kg/s, the parametric analysis shows that the radial paddle is able to match this operating condition perfectly. The optimum match results between the kinematic parameter and structural parameter are also validated through the power consumption test. The research results in this paper will play a significant role in decreasing the power consumption and provide the feasible theoretical reference for further designing the impeller blowers.
Number of references:29
Main heading:Materials
Controlled terms:Agricultural machinery - Blowers - Compressors - Electric power utilization - Energy utilization - Housing - Impellers - Kinematics - Kinetics - Mathematical models  - Optimization - Secondary batteries - Testing
Uncontrolled terms:Different operating conditions - High power consumption - Impeller blowers - Low energy consumption - Parameter optimization - Parametric -analysis - Specific power consumption - Virtual Prototype Technology
Classification code:951 Materials Science - 706.1 Electric Power Systems - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 921.5 Optimization Techniques - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 702.1.2 Secondary Batteries - 618.1 Compressors - 601.2 Machine Components - 525.3 Energy Utilization - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 403.1 Urban Planning and Development - 618.3 Blowers and Fans
DOI:10.3969/j.issn.1002-6819.2013.10.004
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 3>

Accession number:20132516429393
Title:Optimization design of steering trapezoid mechanism based on an improved particle swarm optimization
Authors:Liu, Ling (1); Yan, Guangrong (1); Lei, Yi (1); Xiao, Dan (2); Tang, Xiuying (2)
Author affiliation:(1) School of Mechanical Engineering and Automation, BeiHang University, Beijing 100191, China; (2) College of Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Yan, G.(ygr@caxa.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:76-82
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Errors exist between actual trajectories and theoretic trajectories of vehicle steering trapezoid mechanisms in the process of steering, which leads to shorter service life of wheels and worse vehicle handling, stability, and safety. Parameter optimization of steering trapezoid mechanisms can efficiently reduce these errors and improve the safety of these vehicles. The principal purpose of this paper is to develop an improved particle swarm optimization for an optimal design of steering trapezoid mechanisms. First, a nonlinear optimization model of the steering trapezoid mechanism is established by investigating how they work and how they influence the stability of vehicle maneuvering characteristics. The sum of the absolute value of difference between actual rotational angle of anterolateral steering wheel and theoretical rotational angle of anterolateral steering wheel is taken as the objective function of the nonlinear optimization model, while the bottom angle and steering arm length of steering trapezoid mechanisms are selected to be design variables. After that, an improved particle swarm optimization algorithm (IPSO) is proposed based on the traditional particle swarm optimization by introducing over-flow dealing functions to deal with complicated nonlinear constraints. The core idea of IPSO can be described as follows: complex nonlinear constraints are regarded as over-flow dealing functions, check whether over-flow dealing functions meet restricting condition at each iteration, if not, initialize design variables in proper ranges and then repeat the check, otherwise, go to next iteration. Finally, codes for IPSO are programmed and parameters of steering trapezoid mechanisms for three different models are optimized. To test the accuracy of the IPSO algorithm as proposed above, the nonlinear optimization problems for three different models (Nissan Duke, Patrol GRX and Patrol GL) are given; numerical results show that errors of the objective function's actual values and objective function's optimization values are less than 0.1%, which means that IPSO possesses high accuracy in solving nonlinear optimization problems, and that IPSO is a promising method for solving complicated constraint optimization problems. To verify effectiveness and efficiency of the IPSO algorithm, performance comparison experiments of three intelligent algorithms were analyzed. The problem of the steering trapezoid mechanism of Patrol GRX was carried out, with the Improved particle swarm optimization algorithm (IPSO), traditional particle swarm optimization (TPSO), and particle swarm algorithms based on simulated annealing (SA-PSO) being used as the optimizing parameters. For Patrol GR with the same initialization parameters and error percentage of objective function's actual values and objective function's optimization values (Percentage of Error), the minimum number of iterations to get the objective function's optimum solution, the minimum number of iterations to obtain the objective function's optimum solution (Min-iterationNum), the average number of iterations to obtain the objective function's optimum solution (Ave-iterationNum), and the total number of times to obtain the objective function's optimum solution (Total-Times) were selected as key performance comparison indicators of three intelligent algorithms of performance comparison experiments. The performance comparison experiment results indicates that the proposed new algorithm is superior to the particle swarm algorithm based on simulated annealing and traditional particle swarm optimization in fast convergence and small calculating quantity, but a little inferior to particle swarm algorithm based on simulated annealing in calculation accuracy in the process of optimization.
Number of references:28
Main heading:Particle swarm optimization (PSO)
Controlled terms:Algorithms - Automobile steering equipment - Design - Errors - Experiments - Iterative methods - Maneuverability - Mathematical models - Number theory - Numerical methods  - Optimization - Problem solving - Reactive power - Simulated annealing - Steering - Wheels
Uncontrolled terms:Constraint optimization problems - Effectiveness and efficiencies - Improved particle swarm optimization algorithms - Non-linear optimization problems - Nonlinear optimization model - Over-flow - Particle swarm algorithm - Vechicles
Classification code:921 Mathematics - 901.3 Engineering Research - 706 Electric Transmission and Distribution - 671.1 Ship Design - 663.2 Heavy Duty Motor Vehicle Components - 601.2 Machine Components - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.10.011
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 4>

Accession number:20132516429412
Title:Design and test of switch air-conditioner's zero static error fuzzy controller for eryngii greenhouse
Authors:Zhan, Pengfei (1); Liu, Zhaofeng (1); L&#252;, Hongli (1); Zhao, Lin (2); Duan, Peiyong (1); Jia, Guanggen (1)
Author affiliation:(1) School of Information and Electrical Engineering of Shandong Jianzhu University, Ji'nan 250101, China; (2) Beijing Institute of Technology, Beijing 10081, China
Corresponding author:Liu, Z.(goldauto@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:219-224
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The greenhouse which breeds industrialized eryngii has the characteristics of large number and small size. Among all the environmental indicators in the greenhouse, the temperature is undoubtedly the most important. Because of cost reasons, most of the factory multi-greenhouse eryngii breeding adopts switch air-conditioning as its temperature control equipment Although the cost of this temperature control equipment is high, control is simple; however, control accuracy is lower and cannot meet the demand for the production of crops demanding temperature requirements. In addition, the control devices between multiple greenhouses exhibit individual differences, and the various uncertainties in the external environment continue to influence the greenhouse temperature changing parameters. The static control algorithm, therefore, will inevitably lead to the emergence of the static error. In view of this situation, this paper proposes a control strategy based on an adaptive variable universal fuzzy controller. This paper is organized as follows. Section 0 presents the purpose of this paper and current research situation. In Section 1, the change law of greenhouse's temperature, under the synthesized effect of Switch-air conditioner and variables, is analyzed. Fuzzy controller's inner structures and their design method are detailed in section 2. It also gives the membership grade of the fuzzy controller for the actuator. Section 3 proposes 3 steps to fulfill the adaptive algorithm under a list of limited conditions. In section 4, we do two sets of controlled trials in different conditions and then analyze the results. In section 5, a conclusion section summarizes the main point of the paper. The controlling structure includes the regional decision-making process, two sub-fuzzy controllers, and adaptive aspects. In the control process, the current temperature and the temperature change serve as the controller of the two input. Two sub-fuzzy controller region decision-making processes controls the switching operation, adaptive link to a start and stop cycle of switching the air-conditioning as the rolling optimization unit. At the end of a cycle, the adaptive link blurs according to the current cycle of the two sub-controllers which belong to regions respectively overshoot correction center point of each fuzzy domain to enter a new round of the control cycle. In this paper, we do two sets of controlled trials, the first group of 10 greenhouse before and after joining the adaptive link three cycles of fuzzy control overshoot controlled trials. The test results before and after joining the adaptive link the system overshoot average declined 6.5%, the largest decline was 15%, and 90% of the greenhouse in the second cycle overshoot can be decreased to less than &plusmn; 5%.The second set is static error for fuzzy control of a large greenhouse in controlled trials of 10 cycles before and after joining the static error; the test results show all open areas before joining the adaptive link overshoot in more than 15%, there are two periodic overshoot of 25%, and the closing region of the overshoot is substantially located in the vicinity of 10%. After adding adaptive link after a cycle, only cycle 2 and cycle 5 overshoot was10%, the opening of all the remaining cycle, and the close area overshoot maintained within &plusmn; 5%. The method to achieve this is simple, without the host computer doing a lot of computing work, and is particularly suitable for the control of the factory multiple greenhouse switch conditioning temperature.
Number of references:24
Main heading:Temperature control
Controlled terms:Adaptive algorithms - Air conditioning - Concrete pavements - Controllers - Fuzzy control - Greenhouse effect - Greenhouses - Joining - Plant shutdowns
Uncontrolled terms:Conditioning temperatures - Current research situation - Decision making process - Environmental indicators - Individual Differences - Pleurotus eryngii - Static error - Universal fuzzy controllers
Classification code:921 Mathematics - 732.1 Control Equipment - 731.3 Specific Variables Control - 731 Automatic Control Principles and Applications - 723 Computer Software, Data Handling and Applications - 643.3 Air Conditioning - 451 Air Pollution - 412 Concrete - 408.2 Structural Members and Shapes - 406 Highway Engineering - 402.1 Industrial and Agricultural Buildings
DOI:10.3969/j.issn.1002-6819.2013.10.030
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 5>

Accession number:20132516429411
Title:Nonlinear control of pH value in biomass catalytic process
Authors:He, Xianzhong (1)
Author affiliation:(1) College of Electrical and Information Engineering, Hunan University of Technology, Zhuzhou 412007, China
Corresponding author:He, X.(hxzcxh@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:213-218
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The pH neutralization process has the highly nonlinear characteristic, when you add neutralizer or interference, pH value near the neutralization point changes a lot, while the pH value in the else points are opposite. It is very difficult to control. According to the characteristics of the pH controls in enzyme catalysis, using a parameter adaptive state controller and Hammerstein model control strategies, employing recursive least squares parameter estimation, static nonlinear characteristics of the controller upside down process non-linear part of the compensation and Hammerstein model is used to design the nonlinear model predictive control algorithm. Compared with other controller state for a difficult to control process this has a very good effect. The system engages in uncertainties real-time compensation, so as to improve the enzyme catalytic process in the stability of the enzyme activity. When the temperature random variation occurred, we carried out various controls in the field experimental study, in the enzyme-catalyzed process in the pilot test. Due to the mutual coupling of the temperature and pH in the catalytic process. The enzyme catalysis in the process of test, and the reaction time of 30 minutes and the simple PID control of the pH value of the large fluctuation, resulting in a big decrease in enzyme activity. The model reference adaptive controller under the control of the pH value of the wave is small, thus leading to a small decline in the range of enzyme activity, so as to enhance the catalytic process of the stability of the enzyme activity. In this way, converted into an approximate linear control for the pH of the enzyme catalysis process control not only enables the pH value highly nonlinear control, and automatically changes the controller tuning parameters, and solves the high degree of pH neutralization process linear control difficulties, but also improves the accuracy of the pH control in the enzyme catalysis process. pH neutralization process computer simulation results show that the control algorithm has better control over the quality to PID control. The control method can also be used for zinc smelting, in the chemical industry and other areas of pH control. The result of the typical running status indicates that the derived equations according to the theory have a prominent application value and extended significance for popularization. The control technology can be used in all kinds of chemical industry, agriculture and other areas of pH control, and can reduce the pollution of the environment, and therefore has certain market prospects.
Number of references:23
Main heading:Process control
Controlled terms:Algorithms - Catalysis - Chemical industry - Computer simulation - Controllers - Enzyme activity - Enzymes - Linear control systems - Parameter estimation - pH  - Predictive control systems - Three term control systems
Uncontrolled terms:Adaptive - Hammerstein - Model reference adaptive controllers - Nonlinear characteristics - Nonlinear model predictive control - PH neutralization process - Real-time compensations - Recursive least square (RLS)
Classification code:805 Chemical Engineering, General - 802.2 Chemical Reactions - 801.2 Biochemistry - 801.1 Chemistry, General - 732.1 Control Equipment - 921 Mathematics - 731.1 Control Systems - 723.5 Computer Applications - 723 Computer Software, Data Handling and Applications - 461.9 Biology - 461.2 Biological Materials and Tissue Engineering - 731 Automatic Control Principles and Applications
DOI:10.3969/j.issn.1002-6819.2013.10.029
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 6>

Accession number:20132516429394
Title:Fuzzy evaluation system of agriculture drought disaster risk and its application
Authors:Qin, Yue (1); Xu, Xiangyu (1); Xu, Kai (1); Li, Aihua (2); Yang, Dawen (1)
Author affiliation:(1) State Key Laboratory of Hydroscience and Engineering, Department of Hydraulic Engineering, Tsinghua University, Beijing 100084, China; (2) Water Resources and Hydropower Planning and Design General Institute, Ministry of Water Resources, Beijing 100120, China
Corresponding author:Xu, X.(xuxy12@tsinghua.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:83-91
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Droughts happened frequently in the past few years and caused great loss in economy in parts of China, especially in agricultural production. Analysis of drought risk mainly used qualitative analysis and theory research, but quantitative analysis is few in previous studies. Therefore, it is of guiding significance to establish a fuzzy comprehensive index system taking regional agricultural drought risk as the evaluation targets. To give a quantitative assessment of agriculture drought, a calculation method for regional agriculture drought disaster risk indicators based on analytic hierarchy process (AHP) and fuzzy comprehensive evaluation (FCE) was put forward in this paper. This method includes the identification of agricultural drought disaster indicators, the determination of index weight and the calculation of drought risk comprehensive evaluation index. For the calculation process, firstly, the agricultural drought disaster indicators were identified. The agriculture drought disaster risk indicators system divided into four main indicators, namely hazard indicator (H), exposure indicator (E), vulnerability indicator (V) and drought resistance ability indicator (RE). The first three indicators are objective, while the last one is subjective which includes the influence of human activity. Secondly, the agricultural drought disaster indicators were determined. The indicators were determined based on the social economy, hydrological and meteorological data. Meanwhile, some sub-indicators were selected to form the lower hierarchy of the risk indicators system, and the weights of sub-indicators were calculated by AHP method from the judgment matrices of each main indicator. Finally, drought risk comprehensive evaluation index was calculated. With the normalization of sub-indicators and the calculation of FCE equation of agriculture drought disaster risk, the comprehensive risk level could be calculated. Taking the eight counties of Chengde City in Hebei Province as an example, the comprehensive risk level for each county was analyzed based on the above method. From the distribution of agriculture drought disaster risk indicator, the results showed that the drought risk of counties in the upstream area was generally higher than that in the downstream area and the drought resistance ability was of great difference for each county, which were consistence with some literature. The value of comprehensive risk level was 79, 33 and 16 for Weichang county, Fengning county and Longhua county in the upstream area, respectively. The value of comprehensive risk level was 11, 14 and 8 for Chengde county, Pingquan county and Luanping county in the midstream area, respectively. The value of comprehensive risk level was 3 and 3 for Xinglong county and Kuancheng county in the upstream area, respectively. Also, the sub-indicators of the four indicators varied obviously from county to county, which can provide a basis for targeted drought mitigation activities. Weichang county had a high value of hazard indicator (H=5.1). Fengning county had high values of exposure indicator (E=5.4) and vulnerability indicator (V=5.1). Longhua county had a high value of hazard indicator (H=5.4). Despite the deficiency of this method, including the difficulty of risk verification and the demand of high quality regional data, the results confirmed the rationality of the evaluation method. This method could be used to provide decision support and quantitative basis for the development of effective drought resistance activities.
Number of references:29
Main heading:Drought
Controlled terms:Agriculture - Analytic hierarchy process - Decision support systems - Forestry - Fuzzy set theory - Hazards - Hierarchical systems - Meteorology - Pesticide effects - Risks
Uncontrolled terms:Agricultural drought disasters - Agricultural productions - Analytic hierarchy process (ahp) - Comprehensive evaluation index - Fuzzy comprehensive evaluation - Guiding significances - Quantitative assessments - Vulnerability indicators
Classification code:921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921 Mathematics - 914.1 Accidents and Accident Prevention - 821.0 Woodlands and Forestry - 961 Systems Science - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 723 Computer Software, Data Handling and Applications - 444 Water Resources - 443 Meteorology - 803 Chemical Agents and Basic Industrial Chemicals
DOI:10.3969/j.issn.1002-6819.2013.10.012
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 7>

Accession number:20132516429404
Title:Quantitative analysis of soil erosion and nutrient loss in Yingwugou watershed of the Dan River
Authors:Xu, Guoce (1); Li, Zhanbin (1); Li, Peng (2); Zhang, Tiegang (2); Tang, Shanshan (2)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dry-land Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, 712100, China; (2) Key Laboratory of Northwest Water Resources and Environment Ecology of Ministry of Education, Xi'an University of Technology, Xi'an, 710048, China
Corresponding author:Li, Z.(zhanbinli@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:160-167
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The quantitative study of soil erosion and nutrient loss in a small watershed can provide an important basis for ecological protection, soil, and water conservation, and ecological compensation in the water source areas of the South to North Water Diversion Project. Revised universal soil loss equation (RUSLE) was used to estimate the soil erosion and nutrient loss supported by the geographic information system (GIS) in the Yingwugou watershed; however, the soil erosion intensity of the study area was classified. The results indicated that the annual soil erosion modulus in the Yingwugou watershed was 3140 t/km². This falls in the category of moderate degree erosion. The area above high soil erosion intensity only accounted for 24.1% but the soil erosion amount was 4573.0 t, which accounted for 84.8% of the annual soil erosion amount. The high soil erosion area was mainly distributed in sloping cropland with big slopes, which was the key management area. Soil erosion amounts under different land-use types showed great differences. The annual soil erosion moduluses of forestland, grassland, and cropland were 509.7, 1511.8, and 4606.5 t/km², respectively. The annual soil erosion amount of forestland and grassland was relatively small and the annual soil erosion amount of cropland accounted for 95.3% of the total soil erosion amount in the study area. For each additional 5&deg; slope, the increased soil erosion modulus of different land uses was 1 to 2 times greater than that of each additional 5m for slope length. The annual loss amount of total nitrogen, total phosphorus, and organic matter in topsoil was 3.81, 3.52, and 101.45 t, respectively. The nutrient loss of cropland was serious. The annual loss moduluses of total nitrogen, total phosphorus, and organic matter with sediment were 1.01, 0.75, and 38.43 t/(km² &middot a), respectively. The study could provide a scientific basis for the control of soil erosion and water loss, non-point source pollution, and the construction of clean, small watersheds in the water source area.
Number of references:31
Main heading:Soil conservation
Controlled terms:Biogeochemistry - Biological materials - Ecology - Erosion - Forestry - Geographic information systems - Land use - Landforms - Organic compounds - River pollution  - Sediment transport - Soil pollution control - Soils - Water conservation - Water pollution control - Watersheds
Uncontrolled terms:Ecological compensation - Non-point source pollution - Revised universal soil loss equations - River watersheds - RUSLE - Soil and water conservation - Soil nutrients - South-to-North water diversion project
Classification code:481.1 Geology - 481.2 Geochemistry - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 723.3 Database Systems - 804.1 Organic Compounds - 821.0 Woodlands and Forestry - 461.2 Biological Materials and Tissue Engineering - 403 Urban and Regional Planning and Development - 407 Maritime and Port Structures; Rivers and Other Waterways - 444 Water Resources - 444.1 Surface Water - 453 Water Pollution - 453.2 Water Pollution Control - 454.3 Ecology and Ecosystems
DOI:10.3969/j.issn.1002-6819.2013.10.022
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 8>

Accession number:20132516429395
Title:Sensitivity of the potential evapotranspiration to climate and vegetation in Hanjiang River basin based on S-W Model
Authors:Liu, Yuan (1); Zhou, Maichun (1); Chen, Zhijing (2); Li, Shaowen (3)
Author affiliation:(1) College of Water Conservancy and Civil Engineering, South China Agricultural University, Guangzhou 510642, China; (2) Hydrology Bureau of Guangdong Province, Guangzhou 510150, China; (3) Administration Bureau of Hanjiang River Basin of Guangdong Province, Shantou 515041, China
Corresponding author:Zhou, M.(mczhou@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:92-100
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Potential evapotranspiration (PET) as an estimate of crop water demand and a key input to hydrological modeling, not only affected by the changes in climate, but also affected by changes in vegetation covers. Sensitivity of PET to climate and vegetation is helpful in understanding the impact of climate changes and vegetation covers changes on water resources, and also is important to the optimal allocation of agricultural water resources. In this study, PET was calculated by Shuttleworth-Wallace (S-W) model. Threshold values of vegetation parameters in S-W model were drawn from the literature based on the International Geosphere-Biosphere Programme (IGBP) land cover classification. The spatial and temporal variation of vegetation leaf area index (LAI) was derived from the composite AVHRR NDVI using the SiB2 method. The long-term meteorological dataset at 752 meteorological stations in China was used to provide the required meteorological data. Using the meteorological data from meteorological stations and the monthly composite AVHRR NDVI data from NASA GIMMS during the period of 2000-2006, PET over Hanjiang River basin was estimated by S-W model. It showed that the PET was not only affected by climate, but also changed with vegetation types and the growth of vegetation. PET was very sensitive to vegetation types. The calculated PET of different vegetation in the similar climate condition is quite different. The annual mean PET of evergreen needle leaf forests, croplands and woods savannas was 1136.6, 965.1 and 563.2 mm/a, respectively. The maximum value was twice as the minimum value. The sensitivity of the PET to meteorological factors was analyzed. It showed that the sensitivity of the PET to climate was quite different for different vegetation covers. PET of evergreen needle leaf forests is the most sensitive to vapour pressure. Its sensitivity coefficient was much larger than that of air temperature and solar radiation. The sensitivity of wind speed can be ignored. PET of croplands was sensitive to air temperature, solar radiation and vapour pressure while it was not so sensitivity to wind speed. Among all the meteorological factors, the PET of croplands was the most sensitive to air temperature. PET of woods savannas was also the most sensitive to air temperature, and was also sensitive to vapour pressure, wind speed and solar radiation. Their sensitivity coefficients were very close to each other. The sensitivity of the PET to vegetation LAI was then analyzed. It showed that PET of all vegetation covers was sensitive to LAI, but the sensitivity coefficients were smaller than that of the meteorological factors (except for wind speed). The sensitivity of the PET to LAI was different for different vegetation covers. PET of woods savannas was the most sensitive to LAI, followed by evergreen needle leaf forests and croplands.
Number of references:21
Main heading:Climate models
Controlled terms:Atmospheric temperature - Climate change - Evapotranspiration - Forestry - Meteorology - NASA - Needles - Sensitivity analysis - Solar radiation - Sun  - Vapor pressure - Vapors - Vegetation - Water supply - Watersheds - Wind effects
Uncontrolled terms:Hanjiang rivers - Land cover classification - Leaf Area Index - Meteorological factors - Meteorological station - Potential evapotranspiration - Sensitivity coefficient - Spatial and temporal variation
Classification code:921 Mathematics - 821.0 Woodlands and Forestry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 819.6 Textile Mills, Machinery and Equipment - 804 Chemical Products Generally - 657.2 Extraterrestrial Physics and Stellar Phenomena - 657.1 Solar Energy and Phenomena - 656 Space Flight - 655 Spacecraft - 446.1 Water Supply Systems - 444.1 Surface Water - 443.1 Atmospheric Properties - 443 Meteorology
DOI:10.3969/j.issn.1002-6819.2013.10.013
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 9>

Accession number:20132516429400
Title:Hydraulic calculation of horseshoe cross-section with flat-bottom
Authors:Wen, Hui (1); Li, Fengling (1)
Author affiliation:(1) Department of Architecture and Civil Engineering, Huizhou University, Huizhou 516007, China
Corresponding author:Wen, H.(wenhui-hzu@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:130-135
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:As one of the simplified type of the standard II type horseshoe, the II type horseshoe cross-section with flat bottom is one of the general used shape types for spillway tunnel and irrigation tunnel. However, the hydraulic calculation for this type tunnels has not been reported. Aiming at this problem, a new hydraulic calculation formula was proposed. The II type horseshoe cross-section with flat bottom is consisted of four parts: one flat bottom, two side circular arc arch and one circular arc roof umbrella arch. This simplified horseshoe type is special suitable for the geological conditions with low foundation pressure. The characteristics of hydraulics and mechanics are between horseshoe-shaped and U-shaped arch. Due to the flat bottom, this type can keep a normal water flow regime, and a smoothly connection of the water flow before and behind the tunnel. For obtaining the calculation formula of the normal and critical water depth for II type horseshoe tunnel with flat bottom, its geometrical design of hydraulic tunnel were analyzed. In order to guarantee the status without pressure in a free flow tunnel with changing water level, the free space above the water level was not less than 15% of the whole cross-sectional areas of the tunnel. The upper limit of dimensionless water depth was 1.41. For most of the application engineering, the lower limit of dimensionless water depth was 0.05. After ascertained the utility range of the formula and based on fundamental equations of uniform flow and critical flow, the interrelation between dimensionless water depth and the dimensionless parameter were analyzed. We used the power function as the formula form, and coefficients of the formula were calculated based on the theory of optimization and regression. The calculation formula for normal water depth and critical water depth were obtained. Results showed that the maximum relative error of normal water depth and critical water depth were 0.41% and 0.20%, respectively. This research indicated that the hydraulic calculation formula could be widely used in engineering design and project management with high accurate and simple form.
Number of references:29
Main heading:Water levels
Controlled terms:Arches - Flow of water - Hydraulics - Models - Optimization - Project management
Uncontrolled terms:Application engineering - Dimensionless parameters - Direct calculation formulas - Fundamental equations - Hydraulic calculations - II type horseshoe cross-section with flat-bottom - Maximum relative errors - Water depth
Classification code:921.5 Optimization Techniques - 912.2 Management - 902.1 Engineering Graphics - 632.1 Hydraulics - 631.1.1 Liquid Dynamics - 614.2 Steam Power Plant Equipment and Operation - 408.2 Structural Members and Shapes
DOI:10.3969/j.issn.1002-6819.2013.10.018
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 10>

Accession number:20132516429403
Title:Soil anti-scouribility and its related physical properties on abandoned land in the Hilly Loess Plateau
Authors:Li, Qiang (1); Liu, Guobin (1); Xu, Mingxiang (1); Zhang, Zheng (1); Sun, Hui (3)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dry Land Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China; (2) College of Resource and Environment, Northwest A and F University, Yangling 712100, China; (3) Ansai Field Experiment Station of the Chinese Academy of Sciences, Ansai 717400, China
Corresponding author:Li, Q.(liqiang1011@gmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:153-159
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The abandoned land plays an important role in degraded ecosystem restoration. Large areas of abandoned land and the relatively little disturbance by human activity made it the optimal mode in the process of the project to "convert the farmland into forestland. " Our objective was to determine the impact of abandoned land and their different stages on soil anti-scouribility (AS) and related soil physical properties. In this paper, five natural lands with various abandoned stages (0-43 a) were selected to study the soil AS by using a spatio-temporal substitution method in the Hilly Loess Plateau. Rectangular, undisturbed soil samples (length=20 cm, width=10 cm, and height=10 cm) were taken in the field and were conducted with a hydrological flume (length=2 m, width=0.10 m). The flume contained an opening at its lower base, equaling the size of a metal sampling box, so that the soil surface of the sample was at the same level of the flume surface. The space between the sample box and the flume edges was sealed with a painter's mastic to prevent edge effects. The slope of the flume bottom could be varied and clear tap water flow was applied at an adjusted rate of 4.03 L/min discharge on a washing flume slope of 15&deg; for 15 minutes. During the 15 minutes of each experiment, samples of runoff and detached soil was collected every one minute in the first three minutes and two minutes in the following time using 10 L buckets for determination of sediment concentration. Before being tested, the aboveground biomass was cut level with the soil surface. In this way, only the effects of roots were accounted for. The physical properties mainly included soil bulk density (g/cm³), soil water-stable aggregate content (%), soil shear strength (cohesion C and angle of internal friction &phi;), and soil disintegration rate (cm³/min). Root biomass was determined by the harvest method and dried in the oven. The results indicated that as the years of the abandoned land increased, compared with control (stageI), soil bulk density in the surface layer (0-15 cm) and middle layer (&gt;15-30 cm) were significantly reduced, while little change occurred in the lower soil layer (&gt;30-50 cm). The soil water-stable aggregate content and shear strength, including C and &phi; were also significantly increased in the three studied soil layers. Soil disintegration rate was reduced in all soil layers, especially for the middle and lower soil layers, about 4.2 and 1.8 times the rate of those in the surface soil layer. Soil AS in the surface layer increased rapidly before stage III, and kept stable in the following abandoned stages, while the soil AS in the middle and lower soil layers increased steadily, in approximately 76.9% and 30.7% increments as compared with those of the control. Linear regression equations between the soil AS and the soil physical properties studied in the present paper were well fitted in the three soil layers and the soil water-stable aggregate content and dry root biomass were the determining factors in the reinforcement of soil AS in the abandoned land of the Hilly Loess Plateau.
Number of references:30
Main heading:Shear strength
Controlled terms:Aggregates - Biomass - Erosion - Forestry - Landforms - Physical properties - Soil moisture - Soils
Uncontrolled terms:Abandoned land - Angle of internal friction - Linear regression equation - Loess Plateau - Root - Sediment concentration - Soil physical property - Soil water-stable aggregates
Classification code:821.5 Agricultural Wastes - 821.0 Woodlands and Forestry - 483.1 Soils and Soil Mechanics - 483 Soil Mechanics and Foundations - 931.2 Physical Properties of Gases, Liquids and Solids - 481.1 Geology - 421 Strength of Building Materials; Mechanical Properties - 407 Maritime and Port Structures; Rivers and Other Waterways - 406 Highway Engineering - 422 Strength of Building Materials; Test Equipment and Methods
DOI:10.3969/j.issn.1002-6819.2013.10.021
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 11>

Accession number:20132516429390
Title:Flow field characteristic and test on concentration device of concentrated wind energy turbine
Authors:Ma, Guangxing (1); Tian, De (1); Han, Qiaoli (1); Li, Ming (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Inner Mongolia Agricultural University, Huhhot 010018, China; (2) College of Renewable Energy, North China Electric Power University, Beijing 102206, China; (3) Civil Engineering Institute, Inner Mongolia University of Technology, Huhhot 010051, China
Corresponding author:Tian, D.(tdncepu@yahoo.com.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:57-63
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The hazard of wind shear to large wind turbines cannot be ignored. Concentrated Wind Energy Turbine Generator Systems (CWETS) can increase wind energy density and improve wind energy instability. In order to reveal the flow law of wind energy in a concentrated device, theoretical analysis, numerical calculations, and experimental verification on the concentrated wind energy turbine were carried out. To start, this paper introduces the topic background, reveals the wind shear problem that large wind turbines face, summarizes the research situation of wind turbines wind shear, and presents the research status and advantages of the CWETS. Secondly, the report gives detailed analysis of the concentrated wind energy theory basis, basic thought, technical feasibility, and the relative knowledge of computational fluid dynamics. Then, the concentrated equipment is placed in uniform and parallel to the wind flow in the flow field. With the methods of numerical simulation and test-in-truck experiment, the concentrated equipment is studied. Finally, the concentrated equipment model is set in the flow field with wind speed gradient; using the methods of numerical simulation and tunnel experiment, the traditional concentrated equipment and improved concentrated equipment are studied. The results showed that there was good agreement in the numerical calculation and experiment. Conventional concentrated equipment with the central cylinder of 900 mm diameter is fixed in uniform and parallel flow fields when wind fluid flows through the concentrated equipment. First, the close inner surface fluid is accelerated. At 0.22 m in front of the middle section of the central cylinder, the speed of the close inner surface fluid is faster than the speed at the center axial fluid. The former speed reaches its maximum near the middle of the central cylinder; then with the axial distance increasing, the flow field comes into being, with the faster speed of the center axial fluid than that of close inner surface fluid. It also can be seen, in the central cylinder with 900 mm diameter, the boundary layer effect appears near 50 mm away from the inner surface of the central cylinder. Wave crest 1 appears at 0.11 m section in front of the middle section; wave crest 2 appears at 0.07 m section behind the middle section; wave trough appears at 0.02 m section behind the middle section. In the central cylinder with the 300 mm diameter, the boundary layer effect appears near 15 mm away from the inner surface of the central cylinder. At wind flow sections into the central cylinder and out of the central cylinder, each has a crest, and in the middle of the two peaks is a trough. Uniformity and stability is tested in the experimental wind tunnel, and the wind speed gradient for simulated atmospheric boundary layers in the wind tunnel is also tested. The fluid close to the wall is first accelerated when flowing through the concentrating device. The velocity is greater than the central velocity at 0.22 m before the intermediate section, and then, the central velocity becomes gradually greater than the marginal velocity with the increasing distance. The central cylindrical department has the radial velocity gradient centered in the intermediate axis. The radial velocity gradient in the intermediate section is 2.35 m/s when the flow is 10.74 m/s. For the concentrated equipment models with the same size, values obtained by the numerical calculation are always greater than the experimental data, but the overall trend is the same. The main reason is the simplified numerical simulation model, while the actual constraints of the experiment cannot be embodied in the numerical simulation.
Number of references:25
Main heading:Equipment
Controlled terms:Automobile testing - Boundary layers - Computational fluid dynamics - Computer simulation - Concentration (process) - Cylinders (shapes) - Experiments - Flow fields - Power generation - Velocity  - Wind effects - Wind power - Wind tunnels - Wind turbines
Uncontrolled terms:Boundary layer effects - Concentrated wind energies - Energy instabilities - Experimental verification - Flow field characteristics - Large wind turbines - Numerical calculation - Technical feasibility
Classification code:931.1 Mechanics - 901.3 Engineering Research - 901 Engineering Profession - 802.3 Chemical Operations - 723.5 Computer Applications - 706 Electric Transmission and Distribution - 663 Buses, Tractors and Trucks - 662 Automobiles and Smaller Vehicles - 651.2 Wind Tunnels - 631.1 Fluid Flow, General - 615.8 Wind Power (Before 1993, use code 611 ) - 408.2 Structural Members and Shapes - 408.1 Structural Design, General
DOI:10.3969/j.issn.1002-6819.2013.10.008
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 12>

Accession number:20132516429397
Title:Soil moisture inversion by radar with dual-polarization
Authors:Chen, Jing (1); Jia, Yi (2); Yu, Fan (2)
Author affiliation:(1) School of Remote Sensing and Information Engineering, Wuhan University, Wuhan 430079, China; (2) Chinese Academy of Surveying and Mapping, Beijing 100830, China
Corresponding author:Chen, J.(jechin@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:109-115
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Soil moisture plays a key role in the interactions among the hydrosphere, biosphere, and atmosphere. Traditionally, soil moisture information is measured by ground-based soil moisture monitoring networks, which is accurate but time-consuming and laborious. In this study, a new empirical model is developed for estimating the soil moisture of bare surfaces by dual-polarization ASAR. The steps are as follows: first, a database linked to SAR backscattering coefficients, surface roughness parameters, and soil moisture is built by AIEM (advanced integral equation model). Through mathematical analysis of a simulated database, the influence of roughness and soil moisture are taken into account, respectively. For roughness impact, a new roughness parameter R<inf>s</inf>=S³/L² is defined by combining the traditional roughness parameter S with L. Then, the unknown parameters in the empirical model are only roughness parameter R<inf>s</inf> and volumetric soil moisture m<inf>&nu;</inf>. The soil moisture can be retrieved from dual-polarization SAR observations. Concerning the influence of soil moisture, the Fresnel reflection coefficient &Gamma;⁰ is brought in to take place of m<inf>&nu;</inf> because a better relationship can be built between the Fresnel reflection coefficient &Gamma;⁰ and the backscattering coefficient &sigma;⁰. In this case, Fresnel reflection coefficient &Gamma;⁰ can be directly retrieved from the empirical model, not soil moisture m<inf>&nu;</inf>. The soil dielectric constant &Epsilon; can be determined by Fresnel reflection coefficient &Gamma;⁰ and the Dobson Model, in which soil moisture can be linked with dielectric constant &Epsilon;. To estimate the accuracy of the empirical model, the results of the empirical model were compared with in-situ data in the same location collected at Heihe river basin, Zhangye, in 2008. It concluded that, when &theta; &gt; 25&deg;, S &lt; 1.5 cm, L &isin; (4,18) cm, there was a good relationship between the estimated data and in-situ data. The correlation coefficient R² could be as high as 0.745, meanwhile the RMSE (root mean square error) was 0.478. Because this method requires only dual-polarization SAR data for retrieving soil moisture, and does not need any ground roughness observations, it is suitable for soil moisture retrieval in large regions. However, this new model needs to be validated by more in-situ experiments and combined with vegetation models in order to meet regions covered by vegetation.
Number of references:22
Main heading:Soil moisture
Controlled terms:Backscattering - Electromagnetic wave diffraction - Geologic models - Mean square error - Polarization - Radar - Remote sensing - Synthetic aperture radar - Vegetation
Uncontrolled terms:Advanced integral equations - Backscattering coefficients - Dual-polarizations - Fresnel reflection coefficient - Inversion - RMSE (root mean square error) - Roughness parameters - Surface roughness parameters
Classification code:821 Agricultural Equipment and Methods; Vegetation and Pest Control - 731.1 Control Systems - 716.2 Radar Systems and Equipment - 711.1 Electromagnetic Waves in Different Media - 711 Electromagnetic Waves - 483.1 Soils and Soil Mechanics - 481.1 Geology
DOI:10.3969/j.issn.1002-6819.2013.10.015
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 13>

Accession number:20132516429384
Title:Plant recognition and localization for intra-row mechanical weeding device based on machine vision
Authors:Hu, Lian (1); Luo, Xiwen (1); Zeng, Shan (1); Zhang, Zhigang (1); Chen, Xiongfei (1); Lin, Chaoxing (1)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (2) College of Engineering, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Luo, X.(xwluo@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:12-18
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Intra-row mechanical weeding, as a non-chemical weed control technology, reduces the application of chemical herbicides and is beneficial to the environment protection and sustainable development for agriculture as well. Most crops are cultivated in rows with a defined sowing or transplanting pattern, i.e. with a constant spacing distance. This is an important feature that can be used for plant recognition and localization. The goal of this study presented herein is to propose a recognition and localization approach, taking advantage of the knowledge of the sowing or transplanting pattern, to avoid crop automatically and enter into the intra-row area for intelligent intra-row mechanical weeding device. The RGB imaged plants were distinguished from soil by analyzing the excessive green (2G-R-B) vegetation index image. The Ostu algorithm method was employed to transform a gray image to a binary image. And then the binary image was dilated and eroded three times repeatedly to remove isolated pixels in binary images or to remove noise for subsequent analysis. The standard deviation of longitudinal histogram was used as the scanning line to get the crop row area information in a binary image. The next step was to sum up all pixels of the crop row area per column, thus forming a signal with a frequency that corresponds to the average crop distance. The target regions and center points were obtained by analyzing the lateral histogram with the horizontal scan line. The most probable crop regions were filtered from all the target regions using a sinusoid which was fitted lateral histogram based on the distance between crops. The phasing of the sinusoid was given by least square fit for all the center points. After fusing the center of crop row and the centroid of green plants in binary image, the plants localization were obtained through searching the closest fusion result to the sinusoid peeks. Test results showed that, the method was sufficient in plants recognition and localization for intra-row mechanical weeding under different weather and field conditions. The accurate identification rate was 95.8% with the absolute error of 4.2 pixels in the x-direction and 1.4 pixels in the y-direction for cotton seedlings. An identification rate of 100% with the absolute error of 6.8 pixels in the x-direction and 15.3 pixels in the y-direction was achieved for lettuce seedlings. The position of the crop was correctly determined for 100% of all the images. The positioning error for lettuce and cotton seedlings was 17.6 pixels and 5.0 pixels, respectively. Main factors that influence the performance of the recognition and localization are weed pressure and the plant growth conditions. This study provides the basics for mechanical weed control devices to seedling avoidance and automatic weed control.
Number of references:30
Main heading:Crops
Controlled terms:Agricultural machinery - Binary images - Computer vision - Cotton - Graphic methods - Herbicides - Location - Pixels - Weed control
Uncontrolled terms:Control technologies - Crop recognition - Environment protection - Horizontal scan line - Identification rates - Important features - Mechanical weeding - Standard deviation
Classification code:912 Industrial Engineering and Management - 911 Cost and Value Engineering; Industrial Economics - 821.4 Agricultural Products - 821.1 Agricultural Machinery and Equipment - 803 Chemical Agents and Basic Industrial Chemicals - 723.5 Computer Applications - 723.2 Data Processing and Image Processing
DOI:10.3969/j.issn.1002-6819.2013.10.002
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 14>

Accession number:20132516429399
Title:Calculation of canopy resistance using air temperature difference between canopy top and bottom
Authors:Li, Caixia (1); Zhou, Xinguo (1); Sun, Jingsheng (1)
Author affiliation:(1) Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences, Key Laboratory of Crop Water Use and Regulation, Xinxiang 453002, China
Corresponding author:Sun, J.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:123-129
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to investigate the calculation method of maize canopy resistance under alternative furrow irrigation with water deficit, field experiments were carried out at the experiment field of crop water requirement of Farmland Irrigation Research Institute, Chinese Academy of Agricultural Sciences in 2009 and 2010 seasons. Leaf stomatal conductivity, solar radiation, air temperature, canopy temperature and humidity, and wind speed were measured simultaneously on sunny day at maize growing stage of seeding, jointing, heading, and filling. Three models of canopy resistance, including the model of Jarvis (1976), Ortega-Farias et al (2004), and Brisson et al (1998), were introduced. The temperature difference between canopy top and bottom (&Delta;T<inf>c</inf>) was determined as an environmental factor representing the response of leaf resistance to soil moisture with the relationship between maize leaf resistance and the temperature difference between canopy top and bottom (&Delta;T<inf>c</inf>) with different soil moisture at different growing stages. Therefore, with improving the multi-factors model of Jarvis (1976), the canopy resistance of maize under alternative furrow irrigation with water deficit was developed by introducing a variable of &Delta;T<inf>c</inf>, i.e. the canopy stomatal model based on &Delta;T<inf>c</inf>. There were four response functions of canopy resistance to environmental factors, i.e. solar radiation, vapor press deficit, air temperature, and temperature difference between canopy top and bottom. These response functions was determined with the relationship between the stomatal conductivity of maize leaf and four environmental factors. Parameters of the environmental stress function of the canopy resistance model developed in this study were optimized using the iterative calculation of the least square method. Parameters of b<inf>1</inf>, b<inf>2</inf>, c<inf>1</inf>, d<inf>1</inf>, g<inf>1</inf>, and g<inf>2</inf> in the model were 1.12, 380, -0.387, 0.0048, -0.236, and 1.087, respectively. The canopy resistance model was validated with comparison with the model of Jarvis (1976), Ortega-Farias (2004), and Brisson et al (1998), respectively. Results indicated that daily mean canopy resistance calculated using Jarvis model (1976), Ortega-Farias model (2004), the multi-factors model based on &Delta;T<inf>c</inf>, and Brisson model (1998) was 355.93, 318.75, 300.61, and 253.42 s/m, respectively. The simulated values of Ortega-Farias model (2004) and Jarvis model (1976) were greater than the measured values by 9.70% and 22.50%, respectively. The calculated values of Brisson model (1998) were lower than the measured values by 12.78%. The calculated values of the canopy stomatal model based on &Delta;T<inf>c</inf> were higher than the measured values by 3.36%. Mean absolute error (MAE), standard deviation (SD), and degree of fitting (d<inf>1</inf>) between the measured values and calculated values of the model based &Delta;T<inf>c</inf> were 2.42, 6.77, and 0.89, respectively; and the coefficient of determination (R²) was 0.86, indicating the model proposed had better precision than the model of Jarvis(1976), Ortega-Farias(2004) and Brisson et al(1998). Taking crop, soil and meteorological factors into account, the application scope, data acquisition, and precision of the canopy resistance model based on &Delta;T<inf>c</inf> were better than other methods. Therefore, the improved Jarvis model-based on the temperature difference between canopy top and bottom could be employed to calculate maize canopy resistance under alternative furrow irrigation with water deficit.
Number of references:22
Main heading:Computer simulation
Controlled terms:Atmospheric temperature - Crops - Irrigation - Iterative methods - Least squares approximations - Moisture - Plants (botany) - Soil moisture - Soils - Solar radiation  - Sun - Vapors
Uncontrolled terms:Canopy resistance - Coefficient of determination - Crop water requirements - Iterative calculation - Maize - Meteorological factors - Temperature differences - The difference in temperature between upper and lower canopy
Classification code:821.4 Agricultural Products - 821.3 Agricultural Methods - 804 Chemical Products Generally - 723.5 Computer Applications - 921.6 Numerical Methods - 657.2 Extraterrestrial Physics and Stellar Phenomena - 483.1 Soils and Soil Mechanics - 461.9 Biology - 443.1 Atmospheric Properties - 657.1 Solar Energy and Phenomena
DOI:10.3969/j.issn.1002-6819.2013.10.017
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 15>

Accession number:20132516429408
Title:Economic power supply radius under different distribution transformer installation in rural low-voltage network
Authors:Yang, Jian (1); Xu, Yuejin (1); Wu, Hao (1); Yin, Decong (1)
Author affiliation:(1) College of Information and Electric Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Xu, Y.(xyj@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:190-195
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The distribution transformer is one of the most important pieces of equipment in rural distribution networks. In the construction and reconstruction of a rural power-distribution network, the power-supply radius of a low-voltage network is an important index for planning and design, which is of great significance for reasonable layout of low-voltage distribution power supply, ensuring the quality of power supply, reducing line losses and reducing investment costs. At present there are mainly the following several methods to calculate the power supply radius of a low-voltage power system. The power-supply radius is determined by setting power loss and voltage loss from main power lines as the constraint conditions. In different voltage levels, using the rural electric equipment capacity density and geographic features to divide economic power supply radius is another method. It is also common to calculate the power-supply radius based on the model of unconstrained optimization whose objective function is to minimize the annual cost of the power-supply area. The first two methods are simple and rough, without considering the investment, consumption and other economic factors. The third method involves a comprehensive consideration of the transformer and line investment, consumption and other economic factors, and the power-supply radius obtained is more reasonable and practical. However, this method is still insufficient because it does not consider the investment difference of different types of distribution transformers. Because the installation form of the actual distribution transformer (such as outdoor stage posture or box-type transformer) has a great influence on investment cost (several times or even more), so it is natural that we cannot ignore the influence on economic power-supply radius caused by different installation types. Therefore, this paper starts from the overall economic efficiency and builds the optimization model based on unit power-supply area by minimizing the cost to analyses and count economic radius of distribution transformers of different types in a rural low-voltage network. We can see that the economic power supply radius of a transformer differs by transformer type corresponding to the same load density and maximum load utilization time from the calculation results. So transformer type will affect the economics of power grid construction. Meanwhile, load density and maximum load utilization hour exhibit a similar trend. That is to say, when the density of load or peak load utilization increases, its economic power supply radius decreases. We can conclude that it is more convenient for practical engineering application to use power density to illustrate the changes of economic power supply radius. Power density is the product of load density and maximum load utilization time. The paper proposes to estimate economic radius judging by power density. Finally, the paper gives economic radius recommended value of transformers of different types. It is easy to use the recommended value to estimate the economic radius in a rural low-voltage network; the recommended value can provide technical support in the selecting of economic radius in the power grid construction. Finally, the recommended value of economic power supply radius is given in different power densities and transformer types.
Number of references:25
Main heading:Economic and social effects
Controlled terms:Cost benefit analysis - Costs - Economics - Electric power distribution - Electric transformers - Investments - Networks (circuits) - Optimization - Rural areas
Uncontrolled terms:Distribution transformer - Low voltage network - Low-voltage distributions - Low-voltage power systems - Practical engineering applications - Quality of power supply - Rural distribution networks - Unconstrained optimization
Classification code:921.5 Optimization Techniques - 911.2 Industrial Economics - 911 Cost and Value Engineering; Industrial Economics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 715 Electronic Equipment, General Purpose and Industrial - 714 Electronic Components and Tubes - 706.1.2 Electric Power Distribution - 704 Electric Components and Equipment - 703.1 Electric Networks
DOI:10.3969/j.issn.1002-6819.2013.10.026
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 16>

Accession number:20132516429387
Title:Finite element simulation of soil cutting with rotary knife roller based on ANSYS/LS-DYNA software
Authors:Xia, Junfang (1); He, Xiaowei (1); Yu, Shuisheng (1); Zhou, Yong (1)
Author affiliation:(1) College of Engineering, Huazhong Agricultural University, Wuhan 430070, China
Corresponding author:Xia, J.(xjf@mail.hzau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:34-41
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The straw returning and tillage machine with double roller for high stubble in paddy field had several advantages, such as wide working range, crushing earth evenly, good coverage rate, high working efficiency and so on. The rotary knife roller was the main working part of the machine. The interactions between rotary knife roller and soil included shear, friction and extrusion of knife roller for soil, deformation and failure of the soil and so on. In order to study the interaction characteristics, the soil cutting process of the rotary knife roller was analyzed by Finite Element Method (FEM) software ANSYS/LS-DYNA971 according to the operating feature of the rotary knife roller. The power consumption and cutting resistance of the rotary knife roller were measured by simulation, and the variation rules of equivalent stress of the soil was revealed during the soil cutting process of the rotary knife roller. The maximum values of power consumption and cutting resistance were obtained when the rotational speed was 300r/min and the forward speed was 1.1 m/s, and the values were 6.4 kW and 2820.7 N respectively. The value of power consumption acquired by simulation were accorded with derived value by empiric formulas, which showed that the proposed modeling method was practical and reasonable Furthermore, the maximum equivalent stress of the soil appeared at the inner side surface of the cross knife when lateral blade just cut the soil. Finally, the lateral blade had a lateral push effect on soil in the practical field test, and the adjacent lateral blade had an overlapping time of soil cutting, which could make the machine work more smoothly. The study would provide a theoretical basis for the system parameter's optimal design of the straw returning and tillage machine with double roller for high stubble in a paddy field.
Number of references:32
Main heading:Soils
Controlled terms:Agricultural machinery - Agriculture - Cutting - Cutting tools - Finite element method - Rollers (machine components)
Uncontrolled terms:Cutting resistance - Deformation and failures - Equivalent stress - Finite element method softwares - Finite element simulations - Interaction characteristics - Rotary knife roller - Working efficiency
Classification code:921.6 Numerical Methods - 821.1 Agricultural Machinery and Equipment - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 605 Small Tools and Hardware - 604.1 Metal Cutting - 601.2 Machine Components - 483.1 Soils and Soil Mechanics
DOI:10.3969/j.issn.1002-6819.2013.10.005
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 17>

Accession number:20132516429383
Title:Trace elements on influence of anaerobic fermentation in biogas projects
Authors:Zhang, Wanqin (1); Wu, Shubiao (2); Lang, Qianqian (1); Dong, Renjie (2)
Author affiliation:(1) College of Agronomy and Biotechnology, China Agricultural University, Beijing 100193, China; (2) College of Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Wu, S.(wushubiao@gmail.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:1-11
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The anaerobic digestion of biomass is a multi-stage process involving different types of microorganisms. Biogas projects employing anaerobic digestion and aiming at waste resource utilization are now becoming the most effective and promising techniques used for the treatment of urban waste, industrial wastewater, poultry excreta, and excess sludge from wastewater plants, and so on. In the process, in addition to macronutrients such as carbon (C), nitrogen (N), phosphorus (P), and sulphur (S), trace elements play a crucial role in the growth and metabolism of anaerobic microorganisms. Trace elements such as micro-nutrients are necessary for the metabolism of anaerobic microbes and important components in the anaerobic fermentation enzyme system, which can activate the activity of enzymes in methanogenic systems. Trace elements, such as iron (Fe), cobalt (Co), nickel (Ni), and so on, could promote the growth of the methanogens known to be crucial to the activity of enzymes in methanogenic systems, and to further speed up the biosynthesis of methane. The stimulation and antagonism of trace elements plays a very significant role in the performance and stability of biogas digesters, which are operated with energy crops, animal excreta, crop residues, organic fraction of municipal solid wastes, and other types of organic waste. The deficiency or unavailability of these elements in biogas digesters is probably the first reason of poor process efficiency (fermentation system operation instability and declining gas production) without any other obvious reason, despite proper management and control of other operational and environmental parameters. This paper reviews the biological effects of trace elements, methanogens demand for trace elements and the role of trace elements in methane synthesis on one hand, and the research status at home and abroad about the influence of trace elements such as iron (Fe), cobalt (Co), nickel (Ni), and so on, on anaerobic fermentation on the other hand. Trace elements Fe, Co, and Ni can improve the efficiency of conversion of volatile fatty acids (VFA) and eliminate the phenomenon of the accumulation of VFA. They also could antagonize the inhibitory effect induced by sodium ions, ammonia nitrogen, and increase the methane yield and keep the stability of anaerobic digestion process. Through review, the effects of trace elements on anaerobic fermentation may help to maintain the operational stability of the biogas project. Further, such knowledge is indispensable for a rational dosage of these metals to ensure maximum, high solid substrate conversion rates and to prevent disturbances in reactor performance using a minimum amount of metals. Additionally, understanding the potential environmental risks due to adding trace elements is currently insufficient.
Number of references:90
Main heading:Nickel
Controlled terms:Agricultural wastes - Agriculture - Anaerobic digestion - Biochemistry - Biogas - Cobalt - Enzymes - Fermentation - Iron research - Metabolism  - Metal ions - Methane - Methanogens - Microbiology - Microorganisms - Nitrogen - Physiology - Stability - Trace elements - Volatile fatty acids
Uncontrolled terms:Anaerobic digestion process - Anaerobic microorganisms - Antagonism - Bioavailability - Environmental parameter - Management and controls - Organic fraction of municipal solid wastes - Stimulation
Classification code:961 Systems Science - 804 Chemical Products Generally - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes - 931 Classical Physics; Quantum Theory; Relativity - 951 Materials Science - 801.2 Biochemistry - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 548.1 Nickel - 545.1 Iron - 533 Ore Treatment and Metal Refining - 461.9 Biology - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2013.10.001
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 18>

Accession number:20132516429389
Title:Fault diagnosis of rolling bearing based on dual-tree complex wavelet packet transform
Authors:Xu, Yonggang (1); Meng, Zhipeng (1); Lu, Ming (1)
Author affiliation:(1) Key Laboratory of Advanced Manufacturing Technology, College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
Corresponding author:Xu, Y.(xyg@bjut.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:49-56
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The operation states of rolling bearings which are the most common and important parts in the mechanical equipment, will affect the whole machine operation condition directly. Due to the working environment of rolling, bearing is complicated, the fault vibration signal of rolling bearing is usually non-stationary, and the strong noise interference is contained in the vibration signal at the same time. So it is important to eliminate the noise interference and extract fault feature information effectively for the rolling bearing. Dual-tree complex wavelet packet transform is a new method of signal processing. Dual-tree complex wavelet packet transform has many good characteristics, for example, approximate shift invariance, good directional selectivity, perfect reconstruction, limited data redundancy, efficient computational efficiency and so on. The high frequency part of dual-tree complex wavelet transform that is not decomposed, is further decomposed by dual-tree complex wavelet packet transform, so as to improve the whole frequency band signal frequency resolution and reduce the loss of information. In view of the above situation, a new fault diagnosis method is proposed based on dual-tree complex wavelet packet transform and threshold de-noising. Firstly, the non-stationary fault signal is decomposed into several different frequency band components through dual-tree complex wavelet packet decomposition. Secondly, Kurtosis and the cross-correlation coefficient of each component are obtained and compared. Due to the kurtosis reflecting the signal variations, if the kurtosis value is bigger, the degree of the change of signal is bigger too. The correlation coefficient can reflect the proximity between the component and the original signal at the same time, the correlation coefficient is bigger, the more similar with the original signal. Finally, the components that have a bigger value are chosen to be de-noised by a soft threshold and reconstructed by dual-tree complex wavelet packet transform. The noise interference was eliminated effectively, and the effective signal information was retained at the same time. Thus, the fault feature information was extracted. In this paper, the outer bearing fault test and the engineering practical fault data of rolling bearing were analyzed by dual-tree complex wavelet packet transform and threshold de-noising. In order to contrast analysis, the vibration signals were processed by the traditional discrete wavelet packet transform and threshold de-noising. The signal has the better periodic impact obtained by the method proposed in this paper, and the noise was eliminated ideally. So the fault diagnosis method based on dual-tree complex wavelet packet transform and threshold de-noising can effectively eliminate the noise in the vibration signals. Thus, the fault feature information was extracted and the feasibility and effectiveness of this method is verified.
Number of references:26
Main heading:Trees (mathematics)
Controlled terms:Bearings (machine parts) - Bearings (structural) - Fault detection - Frequency bands - Higher order statistics - Partial discharges - Roller bearings - Signal analysis - Wavelet analysis
Uncontrolled terms:Correlation coefficient - Cross-correlation coefficient - Directional selectivity - Discrete wavelet packet transforms - Dual-tree complex wavelet transform - Dual-tree complex wavelets - Kurtosis - Soft threshold
Classification code:921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921 Mathematics - 716 Telecommunication; Radar, Radio and Television - 922.2 Mathematical Statistics - 701.1 Electricity: Basic Concepts and Phenomena - 422 Strength of Building Materials; Test Equipment and Methods - 408.2 Structural Members and Shapes - 601.2 Machine Components
DOI:10.3969/j.issn.1002-6819.2013.10.007
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 19>

Accession number:20132516429385
Title:Development and test of picking actor in oil-tea camellia fruit picking machine of tooth comb type
Authors:Gao, Zicheng (1); Li, Lijun (1); Li, Xin (1); Min, Shuhui (1); Yi, Chunfeng (1)
Author affiliation:(1) College of Mechanical and Electrical Eng. of Central South University of Forestry and Technology, Changsha 410004, China
Corresponding author:Li, L.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:19-25
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Oil-tea camellia is one of the most important economic forest products in southern China, and it has a characteristic of whose florescence overlaps with the fruiting period. During the fruiting period, the fruits should be picked, while buds falling should be avoided. At present, the oil-tea camellia fruit picking is finished by the classical manual method that results in high cost and lower efficiency. With the promotion of the good varieties and the cultivation method of oil-tea camellia, mechanization and intellectualization of fruit picking have become an important aspect in upgrading the oil-tea industry as well as one of the important development directions of forestry machinery. This paper discussed the development and test of the picking machine of the toothcomb type from several aspects as the following. Firstly, the design of the rotary picking head and the picking arm of the machine were discussed. The picking arm, which consists of two parallel quadrilateral mechanisms connected in series, locates on the end of the picking arm. This kind of structure makes it easy to keep the posture of the picking head during the picking process. The rotary picking head consists of three parallel quadrilateral mechanisms connected in parallel, revolving around the common axis. This type of picking head can increase the picking efficiency significantly. Secondly, the space coordinates of the picking executive mechanism were established in this paper, and the motion equation of mechanism was established by the D-H matrix transform, and the main parameters of the transformation matrix was calculated and analyzed. Thirdly, the field experiments showed that each part of the picking machine of the toothcomb type works in phase and legitimately, and that the power matching is in accordance with the requirements. After the test data were analyzed, a conclusion can be calculated that higher picking efficiency can be obtained. The rate of oil-tea fruits not been picked can be controlled within 3.3 percent, the rate of buds dropping can be controlled within 3.2 percent, and the branches have rarely been damaged when the speed of the picking head raised is about 0.8m/s and the velocity of the picking tooth circumgyrated is about 15r/min. Lastly, there are also some shortages in the picking machine of the toothcomb type. For one thing, there is some existing difficulty in controlling the speed of the rising of the picking head accurately, as the picking arm consists of rotary pairs connected and driven by hydraulic pressure. Therefore, the machine needs a further improvement on this aspect. For another, the picking machine of the toothcomb type can only pick the fruits distributed on the surface layer, so the inner oil-tea fruits can only be picked by manual power. In the end, it seemed unrealistic to thoroughly avoid damage to the branches of oil-tea during the course of picking.
Number of references:28
Main heading:Oil field development
Controlled terms:Actuators - Efficiency - Equations of motion - Forestry - Fruits - Harvesters - Linear transformations - Machinery
Uncontrolled terms:Development directions - Executive mechanism - Hydraulic pressure - Matrix transforms - Picking efficiency - Space coordinates - Tooth comb - Transformation matrices
Classification code:921.3 Mathematical Transformations - 921.2 Calculus - 913.1 Production Engineering - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 632 Hydraulics, Pneumatics and Related Equipment, and Fluidics - 601 Mechanical Design - 512.1.2 Petroleum Deposits : Development Operations
DOI:10.3969/j.issn.1002-6819.2013.10.003
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 20>

Accession number:20132516429406
Title:Detection of Solenopsis invicta nest using spectrum analysis technology
Authors:Wu, Weibin (1); Zhi, Lei (2); Hong, Tiansheng (1); Xu, Yijuan (3); Zeng, Ling (3); Huang, Shuangping (2); Deng, Xiaoling (2)
Author affiliation:(1) Key Laboratory of Key Technology on South Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (2) College of Engineering, South China Agricultural University, Guangzhou 510642, China; (3) Red Imported Fire Ant Research Centre, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Xu, Y.(xuyijuan@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:175-182
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Solenopsis invicta, wihich originated in Brazil, Argentina, Paraguay and the Panama Canal, has been spreading at the speed of 200 km every year since they invaded Mobile, Alabama in the United States from 1918 to 1931. Recently, Solenopsis invicta has indicated a tendency to rapidly spread all over the world, including China. They are polyphagous insects, but prefer high protein or high fat foods, such as the larvae of some small insects or vertebrates and seeds or fruits with high oil. Therefore, they are severely dangerous to human health, public security, agriculture, forestry production, and the ecological environment in the invaded areas. Solenopsis invicta is social insect of the family Formicidae, Hymenoptera with the habit of gregarious nesting. They are strongly offensive against intruders, and they will attack the intruders in full strength once their nest is disturbed. Thus, some experts think that the threat of Solenopsis invicta in China cannot be ignored and that corresponding measures should be imminently taken to prevent the Solenopsis invicta invasion. Research on the detection method of a Solenopsis invicta nest to eliminate Solenopsis invicta from the source is of practical significance to the prevention of a Solenopsis invicta disaster. Therefore, finding out the location of a nest of Solenopsis invicta is of more practical value than only exterminating Solenopsis invicta. The feasibility of detection of a nest of Solenopsis invicta based on spectrum analysis technology was examined by using an optical spectrum instrument with reflect characteristics. A differential coefficient method and a logarithmic method to analyze original spectral reflectivity were used. The method of using character factors was studied to get the best waveband for distinguishing the ant nest from other things. An Eculidean distance method was used to calculate the average distance, and effective band of the nest of Solenopsis invicta's recognized effect. In addition, the average of the Euclidean distance of different features is greater than the average of the Euclidean distance of the same feature, and the samples, which were collected and measured by the laboratory hyper-spectral imager to verify the reliability of the selected band. Finally, the results were compared with the traditional method. We randomly selected eight sample points in the Wushan Square of South China Agricultural University. Using the traditional method and a spectrum analytical method to prove it, we got the same result. However, it is more convenient and faster to get the information by using the spectrum analytical method. As a result, the effective wavebands to recognize the Solenopsis invicta nest mostly concentrate on 701-1510 nm, which are mainly red light bands and near-infrared bands. Additionally, the observation shows that the original spectrum and the logarithmic method could be used to distinguish the nest of Solenopsis invicta from common soil and grass. Moreover, the latter can make it clearer than the others, while the spectrum first-order differential method and the logarithmic after a differential transformation could distinguish between grass and ant nest soil, or grass and common soil, but not between Solenopsis invicta nest soil and common soil. This observation may provide useful information for detecting the Solenopsis invicta nest.
Number of references:30
Main heading:Information use
Controlled terms:Disaster prevention - Forestry - Oils and fats - Pest control - Probes - Soils - Spectroscopy - Spectrum analysis - Testing
Uncontrolled terms:Corresponding measures - Differential coefficient - Differential transformation - Ecological environments - Euclidean distance - First-order differentials - Solenopsis invicta - Spectral reflectivity
Classification code:944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 921 Mathematics - 914.1 Accidents and Accident Prevention - 903.3 Information Retrieval and Use - 821.0 Woodlands and Forestry - 804.1 Organic Compounds - 803 Chemical Agents and Basic Industrial Chemicals - 801 Chemistry - 483.1 Soils and Soil Mechanics - 423.2 Non Mechanical Properties of Building Materials: Test Methods
DOI:10.3969/j.issn.1002-6819.2013.10.024
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 21>

Accession number:20132516429415
Title:Zoning approach of suitable areas for high quality capital farmland construction
Authors:Wang, Xinpan (1); Jiang, Guanghui (1); Zhang, Ruijuan (1); Zhao, Tingting (3); Qu, Yanbo (4)
Author affiliation:(1) State Key Laboratory of Earth Surface Process and Resource Ecology, Beijing Normal University, Beijing 100875, China; (2) College of Resources Science and Technology, Beijing Normal University, Beijing 100875, China; (3) Faculty of Agroforesty and Medicine, The Open University of China, Beijing 100031, China; (4) School of Public Management, Shandong University of Finance and Economic, Jinan 250014, China
Corresponding author:Jiang, G.(macrophage@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:241-250
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Large-scale, high quality capital farmland construction, which plays an important role in guaranteeing national food safety, modern agriculture development, and new rural construction, is regarded as one of great national strategies in China. However, studies on how to establish suitable zones for quality facilities in capital farmland construction have not been available until now. With Pinggu District, Beijing, as the study area, this article managed to establish the zoning approach of suitable areas. First, it deployed the multi-factor assessment method, which contained 11 indexes on the aspects of soil quality, site condition, farmland spatial morphology, and agriculture infrastructure to evaluate the natural quality of capital farmland. A second modification method was used to get the capital farmland's comprehensive quality; the effect of location condition, urbanization pressure, and ecological security on capital farmland were considered in this step. According to the definition of quality facilities in capital farmland, capital farmland which is presently in good condition, or which can be transformed into good condition in the future, is the right one for quality facilities. Therefore, capital farmland with the highest ranking after evaluations were those who had already construction zones and had already achieved the construction standard. For some capital farmlands, the limiting factors and their improvement potential to become quality facilities were analyzed. Based on the evaluation and analysis results, some other zones deemed suitable were identified as well. This study shows that regional capital farmland's natural quality displays a declining trend from the plains to the semi-mountain regions, then to the mountain regions. Capital farmland in Mafang Town, Daxingzhuang Town, and Macahngying Town had the highest natural qualities. While mainly affected by the pressure of urbanization development and ecological security, only capital farmland in Daxingzhuang Town and Macahngying Town still remained on the top of the comprehensive quality list. Finally, 6036.98 hm2, or 43.54%, of the total capital farmland is suitable for quality capital farmland construction. And, among them, 1026.70 hm2, gathering in two plain towns, Daxingzhuang Town and Machangying Town, had almost achieved the construction standards. The other 5010.28 hm2, though not good enough at present, can be transformed to reach the construction standards. Capital farmlands inside this category are districts over the plains and semi-mountain areas in the south. According to different regional characteristics, quality facilities in farmland construction should be carried out differently. Farmland in the plains, which had almost reached the construction standards, should develop high-end and modern agriculture. For other regions, strategies that can improve their present limiting factors should be carried out first. The south plain region under high urbanization pressure should pay great attention to balance the development of urbanization and agriculture when constructing these quality facilities. Semi-mountain regions need improve the quality of their capital farmland with the condition of guaranteeing a healthy ecological environment.
Number of references:24
Main heading:Farms
Controlled terms:Consolidation - Ecology - Land use - Landforms - Quality control - Standards - Zoning
Uncontrolled terms:Assessment methods - Comprehensive qualities - Ecological environments - Evaluation and analysis - High quality - Modification methods - Pinggu districts - Regional characteristics
Classification code:913.3 Quality Assurance and Control - 902.2 Codes and Standards - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 483 Soil Mechanics and Foundations - 481.1 Geology - 454.3 Ecology and Ecosystems - 403 Urban and Regional Planning and Development
DOI:10.3969/j.issn.1002-6819.2013.10.033
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 22>

Accession number:20132516429398
Title:Spatial distribution of irrigation water quota of highland barley in Tibet region
Authors:Luo, Hongying (1); Cui, Yuanlai (2); Zhao, Shujun (2)
Author affiliation:(1) Tibet Agricultural and Animal Husbandry College, Nyingchi Prefecture 860000, China; (2) State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
Corresponding author:Luo, H.(lhy_xz@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:116-122
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The objective of this study was to estimate the irrigation water quota and their spatial distribution of highland Barley in Tibet. Tibetan plateau has the characters of high altitude, low air pressure, vast geographic, and has significant differences on climate spatial distribution. Until now, Tibet has very few measured irrigation and drainage experiment data of crops. This paper tried to combine theoretical calculation and survey data together to find a method to calculate the irrigation water quota and obtain a contour map under different irrigation frequency in convenient for project design. Four represent highland barley planting sites in each of four agricultural growth partitions of Tibet were selected to get information on irrigation, cultivation, soil conditions and meteorological characteristics, then 28 meteorological stations' long series of climate data were gathered. To calculate the accurate irrigation water quota of Tibet highland barley, water balance method was applied to calculate daily water balance processes during the growth period. In this process, precipitation, effective precipitation, root zone soil moisture, evapotranspiration, percolation, drainage and so on factors were used. Root zone's soil water was determined by scheming wetness depth and appropriate upper and lower soil moisture limit, and ET<inf>c</inf> (evapotranspiration) was determined by FAO. K<inf>cini</inf>, K<inf>cmid</inf>, K<inf>cend</inf> were modified considering soil and crop evaporation separately by recommended dual crop coefficient. K<inf>c</inf> of four typical sites were calculated, and then irrigation water quota from 1957 to 2009 were calculated by daily water balance in different hydrological years. By comparing the calculated results with surveyed irrigation data, four sites' calculated results were validated, and then the other 24 sites of the 4 partitions' irrigation water quota were also calculated. According to 28 sites' results, Kringing interpolation method was used to get the contour map of Tibet highland barley irrigation water quota in different hydrological years. Climate factors that may interpret irrigation water quota for highland barley were analyzed using Kringing method and contour maps were also obtained. Results showed, in general, from the northwest to the southeast, irrigation water quota decreased gradually. Highland barley irrigation water quotas in Tibetan decreased with precipitation and increased with temperature and ET<inf>0</inf>.
Number of references:18
Main heading:Irrigation
Controlled terms:Atmospheric pressure - Crops - Cultivation - Evapotranspiration - Geographic information systems - Lasers - Moisture - Soil moisture - Solvents - Spatial distribution  - Surveys - Water supply
Uncontrolled terms:Contour line - Drainage experiments - Highland barley - Meteorological station - Root zone soil moistures - Significant differences - Theoretical calculations - Tibet
Classification code:921 Mathematics - 821.4 Agricultural Products - 821.3 Agricultural Methods - 803 Chemical Agents and Basic Industrial Chemicals - 744.1 Lasers, General - 723.3 Database Systems - 483.1 Soils and Soil Mechanics - 446.1 Water Supply Systems - 444.1 Surface Water - 443.1 Atmospheric Properties - 405.3 Surveying
DOI:10.3969/j.issn.1002-6819.2013.10.016
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 23>

Accession number:20132516429418
Title:Development and performance test of fine manipulation environment control for Oolong tea vibrating fine manipulation equipment
Authors:Hao, Zhilong (1); Chen, Jibin (3); Jin, Xinyi (1); Lin, Qingjiao (4); Huang, Yibiao (1)
Author affiliation:(1) College of Horticulture, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (2) Tea Research Institute, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (3) College of Mechanical and Electronic Engineering, Fujian Agriculture and Forestry University, Fuzhou 350002, China; (4) YUN-He Machinery Limited Company, Anxi 362400, China
Corresponding author:Jin, X.(jxy427@tom.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:269-277
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Fine manipulation is the key step during the Oolong tea process. The aroma and taste of Oolong tea were brought out from the step which is repeatedly and alternately rocking and airing. The traditional fine manipulation of Oolong tea is "rocking and airing in different place" with air-conditioning in south Fujian. The process by which tea leaves are put into a mechanical cylinder by turns is called the rocking technique. Then tea leaves are laid into a sieve in an air-conditioned room in what is called an airing technique. The traditional fine manipulation wastes much labor consumption and the3 working posture was difficult to adapt with the spreading and moving of leaves by workers due to the need to carry out the rocking and airing techniques in different place. A larger area and more energy were wasted in the air-conditioning room, and conditions are difficult even. In order to solve those problems, new vibrating fine manipulation (VFM) equipment was developed. The equipment has the combined capability of rocking, airing and environment control techniques. It consisted of the power system, vibrating device, and environment control system. The power system consisted of the power source and eccentric, which could provide driving force to vibrating tea leaves. The vibrating device was composed of a vibrating basket, including a vibrated grid and the static cabinet. Moreover, it could provide spaces for vibrating and airing. The environment regulation system consisted of temperature and humidity adjusted devices including new wind installation and air pipelines, which could provide suitable environmental conditions for the fine manipulation process. The environment regulating performance test of the equipment (ZQ) was investigated with the Tieguanyin variety in spring and summer. The study used the traditional fine manipulation technique with air-conditioning (CK) as a check in south Fujian. ZQ<inf>1</inf>-Vibrating and airing all selected air conveying high gear. ZQ<inf>2</inf>-Vibrating selected air conveying high gear, and airing at low. ZQ<inf>3</inf>-Vibrating and airing all selected air conveying low gear. The results showed that it could effectively control the environment parameters. The velocity of the airflow was controlled at 0.46-0.64 m/s between the tea layers, according to breeze requirements (0.5 m/s). Meanwhile the air temperature was regulated between 22&deg;C and 24&deg;C. It was significantly lower than the temperature of the natural fine manipulation environment in spring (P&lt;0.05). Moreover air relative humidity was regulated between 60% and 80%. It was significantly lower than the humidity of the natural fine manipulation environment in spring (P&lt;0.05). CO<inf>2</inf> volume fraction was controlled between 300 and 400 &mu;l/L. It was significantly lower than the air-conditioning fine manipulation environment in summer (P&lt;0.01). The results showed that the equipment takes advantages of working posture comfort, labor and energy saving. The quality of vibrating fine manipulation raw tea was significantly better than the traditional tea (P&lt;0.01). In conclusion, the working posture discomfort of six is only 1/3 in contrast with the traditional method. Then labor and energy consumption with the new equipment is only 1/2 in contrast with the traditional method. The results could provide the technical basis for continuous, clean, standardized processing of Oolong tea.
Number of references:30
Main heading:Equipment
Controlled terms:Air - Air conditioning - Carbon dioxide - Control - Energy utilization - Environmental regulations - Environmental testing
Uncontrolled terms:Environment control - Environment control systems - Environment regulations - Environmental conditions - Manipulation techniques - Oolong tea - Temperature and humidities - Vibrating devices
Classification code:901 Engineering Profession - 804.2 Inorganic Compounds - 804 Chemical Products Generally - 732 Control Devices - 731 Automatic Control Principles and Applications - 643.3 Air Conditioning - 525.3 Energy Utilization - 454.2 Environmental Impact and Protection - 454 Environmental Engineering
DOI:10.3969/j.issn.1002-6819.2013.10.036
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 24>

Accession number:20132516429413
Title:Grey prediction compensation algorithm for the uncertainty and interference of greenhouse temperature control system
Authors:Zhang, Jun (1); Zhang, Kanyu (1)
Author affiliation:(1) School of Mechatronics Engineering and Automation, Shanghai University, Shanghai 200072, China
Corresponding author:Zhang, J.(tshzhangjun@tsinghua.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:225-233
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The control effect of the conventional control method to the greenhouse temperature depends on the accuracy of the plant model and interference measurement. However, an accurate model of the greenhouse is difficult to obtain because of characteristics of the greenhouse such as uncertainty, imprecision, time-varying, multi-disturbance, etc., with the interference being particularly difficult to accurately measure. For example, the conventional PID control algorithm, widely used in many respects with a good performance record, has poor adaptability and weak robustness when used in greenhouses, and the smith predictive control, used in time delay systems to compensate temperature hysteresis, requires precise mathematical object model. Thus, the usual PID Smith predictor controller often has overshoot and oscillation, generating a large amount of energy consumption in the process of temperature adjustment when used in the greenhouse temperature control system. Therefore, the grey prediction compensation control algorithm is adopted for compensating the aforementioned characteristics of the greenhouse. The advantage of the proposed control strategy is its getting rid of the dependence on conventional control algorithms in the plant model accuracy and interference measurement accuracy, and bypassing the theoretical and technical obstacles in obtaining the object model and interference. Both the simulation and actual operation indicated that the proposed control strategy achieves satisfactory control effect and the system accuracy is significantly improved. Statistical analysis indicated that the correlation coefficients between the estimated value and the true value of the uncertainty and interference grey parameters is 0.9968, 0.9804, and 0.9938, respectively, and the coefficient of determination between them is 0.9935, 0.9585, and 0.9871, respectively. The grey parameters absolute error mean is -0.11510, -0.26733, and -0.31035, and the variance is 0.05150, 0.16324, and 0.09474, the grey parameters relative error mean is -1.68%, -8.06%, and -8.73%, and the variance is 0.01368, 0.00533, and 0.00581. The correlation coefficient between the measured temperature curve and the simulation temperature curve is 0.973972, and the coefficient of determination between them is 0.948621. Also, the overshoot and oscillation in the process of temperature regulation is weakened or eliminated, so the energy consumption is greatly reduced, which not only meets the temperature requirements, but also achieves energy-savings.
Number of references:30
Main heading:Uncertainty analysis
Controlled terms:Algorithms - Delay control systems - Energy utilization - Forecasting - Greenhouses - Temperature control - Three term control systems
Uncontrolled terms:Coefficient of determination - Correlation coefficient - Greenhouse temperature - Grey prediction - Interference measurements - Simulation temperature - Smith predictive control - Temperature regulations
Classification code:922.1 Probability Theory - 921 Mathematics - 731.3 Specific Variables Control - 731.1 Control Systems - 723 Computer Software, Data Handling and Applications - 525.3 Energy Utilization - 402.1 Industrial and Agricultural Buildings
DOI:10.3969/j.issn.1002-6819.2013.10.031
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 25>

Accession number:20132516429407
Title:Dynamic prediction on leaf length of maize based on metabolic model GM(1,1)
Authors:Zhao, Xiaoli (1); Ma, Xinming (1); Wang, Jucai (1); Ye, Jing (1)
Author affiliation:(1) College of Information and Management Science, Henan Agricultural University, Zhengzhou 450002, China; (2) Henan Prov Commissariat Crop Physiol Ecol and Genetic Improvement of Min of Natl Key Lab Breed Base, Zhengzhou 450002, China
Corresponding author:Ma, X.(xinmingma@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:183-189
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The research background of this paper focused mainly on two aspect elements. The first one was fast development on study of plant virtualization under the support policy of agricultural information in China and abroad. The other one was further necessary combination of subjects among management science, computer science, and agronomy. The Grey modeling method from management science, tools from computer science, and experimental design methods from agronomy were all used in this paper. Through this research, correct metabolic GM(1,1) from management science, which is helpful to dynamic simulation growth of maize leaf in research of virtual plant, was expected. The research method and content in general were as follows: To achieve the dynamic prediction of virtual maize, this paper, taking the maize three-ear-leaves as the research object, analyzed the dynamic changes of length of maize leaf under different nitrogen levels (150, 300 and 450kg/hm²) with the method of metabolic GM(1,1). GM(1,1), which has the advantages of requiring fewer message parameters, simplicity, and easy-building, is a grey-dynamic-prediction model. Through the effect of sequence operator to few-data, developing regulations of objects was researched, and the dynamic developing regulation was also simulated. Field experiments which had the same experimental design were made in years 2010 and 2011. Then, the sample data from 2010 and 2011 were used to construct and test models. Taking the data of inferior leaf in three-ear-leaves from 2010 as an example, the proper modeling steps were followed. First, the sample data should be processed with the method that the length of leaf should be divided by the effective accumulated temperature which was needed during the growth of the leaf, which produced a series of data sequences whose units were cm/&deg;C. Second, the final data sequence should be formed by adding the newest data and rejecting the oldest data in that sequence. Finally, the model parameters, ratios of mean square deviation, and mean relative errors of models were identified through a series of calculations including one accumulating generation, mean generation with consecutive neighbors, and least square estimation method. Meanwhile, in order to verify the universality of this model, the sample data of 2011 was also used; to be precise, all the methods and measures used in the process of building models with sample data from 2010 were all used with the sample data of 2011. The experimental results showed that the ratios of mean square deviation and the mean relative errors from the models that were created by the data sequences were all less than 0.0811 and 0.0471 respectively, and that the accuracy of these models was better than level 2, which revealed a high accuracy. The results obviously verified the feasibility and effectiveness of the metabolic GM(1,1) in simulating the length of maize leaf and also provided a theoretical reference for the dynamic change simulation of maize during its growth.
Number of references:28
Main heading:Dynamic models
Controlled terms:Agronomy - Computer science - Computer simulation - Errors - Forecasting - Grain (agricultural product) - Least squares approximations - Management science - Metabolism - Models  - Nitrogen - Plants (botany) - Research - Statistics - System theory
Uncontrolled terms:Accumulated temperatures - Accumulating generation - Agricultural informations - Dynamic prediction - Experimental design method - Least square estimation - Plants - Virtual maize
Classification code:901.3 Engineering Research - 902.1 Engineering Graphics - 912.2 Management - 921 Mathematics - 921.6 Numerical Methods - 922.2 Mathematical Statistics - 961 Systems Science - 821.4 Agricultural Products - 461.9 Biology - 721 Computer Circuits and Logic Elements - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 804 Chemical Products Generally - 821.3 Agricultural Methods
DOI:10.3969/j.issn.1002-6819.2013.10.025
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 26>

Accession number:20132516429401
Title:Effects of temperature and bulk density on measurement precision of soil moisture sensor based on frequency domain reflectometry
Authors:Guo, Wenchuan (1); Song, Kexin (1); Zhang, Peng (1); Han, Wenting (2)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling 712100, China; (2) Institute of Water and Soil Conservation, Northwest A and F University, Yangling 712100, China; (3) Institute of Water Saving Agriculture in Arid Areas of China, Northwest A and F University, Yangling 712100, China
Corresponding author:Han, W.(hanwt2000@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:136-143
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Moisture content of soil is helpful for water-saving irrigation. Soil moisture sensors using frequency domain reflectometry (FDR) are more and more popular in market. Soil temperature is a major factor affecting moisture measurement precision. So it has been widely considered in developing FDR soil moisture sensor. However, volume density, which is also a major factor influencing measurement precision of soil moisture, has been considered hardly. To investigate the comprehensive influence of temperature and volume density on moisture content by FDR moisture sensor, Lou soil in Yangling region, Shaanxi Province, were used as samples, and DSW-T2 soil temperature and moisture sensor (current output type) using FDR technology, was used as instrument to study the influence of moisture content at seven levels (3.82%, 7.58%, 9.29%, 11.65%, 14.87%, 18.61%and 21.43% in wet basis), volume density at five levels (0.91 g/cm³, 1.00 g/cm³, 1.09 g/cm³, 1.21 g/cm³ and 1.30 g/cm³) over temperature range from 2.5&deg;C to 50&deg;C at 2.5&deg;C interval on output current. DM6801 digital temperature sensor was used to measure soil temperature and to detect precision of DSW-T2 on temperature measurement. A comprehensive mathematical model between output current, moisture content, volume density and temperature was established. Newton iteration method was applied to predict moisture content under laboratory conditions. The model's feasibility in predicting moisture content from 3.82%~21.43% and volume density from 0.91g/cm³-1.30g/cm³ at 2.5-50&deg;C was verified. The results indicated that the output current of DSW-T2 increased with increasing moisture content, volume density and temperature over the investigated range of each factor. The absolute error between calculated temperature from obtained output current of DSW-T2 and measured one using DM6801 was within -3.8%-10.7%. The absolute error between calculated moisture content by output current of DSW-T2 and measured one by oven-drying method was -2.2&deg;C-2.4&deg;C. A quadratic model with three-degree of freedom could be used to describe the relationship between output current of DSW-T2 and moisture content, volume density and temperature of soil. At 0.05 significant level, soil moisture content, temperature and volume density had significant effect on the model. The absolute error between calculated output current and measured one was between -1.167-1.216mA. The absolute error between calculated moisture content and actual one was within -2.638%-2.812% when the output current, temperature and volume density were given. By comparing the moisture content obtained by DSW-T2 soil temperature and moisture sensor with out volume density information and calculated one by the regressed three-degree model considering the volume density, it showed that considering volume density is helpful to improve moisture measurement precision. The study offers useful information on developing a comprehensive measurement model for FDR soil moisture sensor with temperature and volume density compensation functions.
Number of references:26
Main heading:Temperature
Controlled terms:Frequency domain analysis - Geologic models - Iterative methods - Mathematical models - Moisture - Moisture determination - Moisture meters - Reflection - Reflectometers - Soil moisture  - Soils - Temperature measurement
Uncontrolled terms:Comprehensive measurement - Digital temperature sensor - Effects of temperature - Frequency domain reflectometry - Laboratory conditions - Newton Iteration Method - Volume density - Water-saving irrigation
Classification code:941.3 Optical Instruments - 921 Mathematics - 801.4 Physical Chemistry - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 711 Electromagnetic Waves - 483.1 Soils and Soil Mechanics - 481.1 Geology - 641.1 Thermodynamics
DOI:10.3969/j.issn.1002-6819.2013.10.019
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 27>

Accession number:20132516429388
Title:Influencing factor analysis of cabbage root cutting force based on orthogonal test
Authors:Li, Xiaoqiang (1); Wang, Fen'e (1); Guo, Weijun (2); Gong, Ziwei (1); Zhang, Juan (3)
Author affiliation:(1) Engineering College, Gansu Agriculture University, Lanzhou 730070, China; (2) School of Mechanical Engineering, Longdong University, Qingyang 745000, China; (3) Mechanical and Traffic College, Xinjiang Agriculture University, Wulumuqi 830000, China
Corresponding author:Wang, F.(wangfene@qq.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:42-48
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The development of a cabbage harvester is urgent in China. The cabbage harvest is still in a condition of artificial operation, which results in labor intensity and low efficiency. Therefore, a kind of cabbage harvester is needed to finish the task. The cutting device plays an important role in the process of the cabbage harvest. In order to design a more reasonable cutting mechanism with a better cutting effect for the 4YB-I cabbage harvester, single factor and multi-factor orthogonal tests were carried out on the multi-function testing machine of microcomputer control. These factors were the main influencing factors of the cutting force applied to cabbage root. The maximum diameter of cabbage root chosen was 30 mm. Each experiment was carried out between top leaves and with a distance from the top leaves of 40 mm. The experiment was started on the distance from the top leaves of 40 mm. The main influencing factors were blade types, cutting ways, cutting speeds and cutting positions. Blade types were smooth-edge blade and serrated blade. Cutting ways were vertical cutting and sliding cutting. The angle of sliding cutting was 30&deg;. To account for the influencing universality of cutting speed, cutting speeds were chosen randomly. They were 50, 100, 150 mm/min in the paper. When experiments of blade types and cutting ways were carried out, 60 similar cabbage roots were chosen, which were divided into groups of twelve. When experiments of cutting speeds were carried out, 135 similar cabbage roots were chosen, which were divided into groups of nine. Each group experiment was conducted five times to get an average. In order to cut the cabbage root cleanly, the work scope of the cutter was between top leaves and the distance from the top leaves was 40 mm. The above experiments were all done on distances from the top leaves of 40, 20, or 5 mm. Based on the single factor orthogonal test, a multi-factor orthogonal test was carried out in a different cutting way, blade type and cutting position. Finally, experimental dates were analyzed by an analysis of variance. In the experiment, some results were obtained. Cutting position on the cabbage root had the greatest effects on the cutting force. The cutting force would be decreased with the changing of the position of the cabbage root, which showed that the best position was between the top leaves and with the distance from the top leaves of 40 mm. Cutting force could be greatly reduced by using a serrated blade with the angle of sliding cutting. The cutting force of the cabbage root would be decreased with the increasing cutting velocity. It was good for smoothly cutting to keep a certain cutting speed, which was 150 mm/min. At this time, the maximum cutting force was 97.8 N. The changing of the cutting speed in the experiment has provided an actual cutting speed of cutter of 4YB-1 cabbage harvester with a theoretical basis. The best way of cutting cabbage root was using a serrated blade with sliding cutting angle. The best position of cutting had provided a theoretical basis for the installation position of the cutter of the 4YB-I cabbage harvester.
Number of references:29
Main heading:Cutting
Controlled terms:Experiments - Harvesters - Orthogonal functions - Speed
Uncontrolled terms:Cabbage - Cutting mechanisms - Cutting positions - Installation position - Maximum cutting force - Microcomputer control - Root - Sliding cutting angles
Classification code:604.1 Metal Cutting - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 921 Mathematics - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2013.10.006
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 28>

Accession number:20132516429416
Title:Zoning and mode of rural residential land consolidation based on location potential theory
Authors:Shuang, Wenyuan (1); Hao, Jinmin (1); Ai, Dong (1); Huang, Xiaoying (1); Zhang, Ling'e (1); Meng, Peng (1); Zhu, Chuanmin (1)
Author affiliation:(1) Key Laboratory of Agricultural Land Quality and Monitoring, College of Resources and Environment Science, China Agricultural University, Beijing 100193, China
Corresponding author:Hao, J.(jmhao@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:251-261
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Rural residential land consolidation is an important part of rural land consolidation, which is also helpful in redeveloping rural vacant and underutilized land, prompting rural land use intensity, improving agricultural production and facilitating rural infrastructure, etc. On the occasion of urban and rural integrated developments, relevant theories and practices should be advanced or adopted to improve the feasibility of local rural residential land consolidation. With the help of location potential theory, this paper performed quantitative analysis of rural residential land from a location perspective. After analyzing the impacting factors like traffic accessibility, comprehensive aggregation size and other factors on the location potential, the location potential model was built to calculate the location potential and corresponding location potential capacity of each rural residential land area. Then consolidation zones and corresponding modes were put forward according to the traits of the location potential and related capacity of each rural residential land via geographic information system software. This paper selected Quzhou County, Hebei Province, as a case to validate the feasibility of location potential theory in specific rural residential land consolidation. On the basis of analysis and overlap of the graphic data of traffic accessibility, comprehensive aggregation size, and other factors, location potential and corresponding location potential capacity of each rural residential land were acquired which could provide a platform for the determination of zones and modes. The final rural residential land consolidation modes in each zone can be classified into five types, namely reserving, modifying, expanding, rebuilding, and demolishing. Disituan Village in Disituan Town and Caishang Village in Quzhou Town are typical rural residential lands belonging to the demolishing type, which can be consolidated according to related village plans to strengthen the spatial distribution of county, town, and village functions. Making use of the fiscal, human, and industrial advantages, new villages with modern infrastructure could be developed. Preserving-typed villages like Baizhai Village in Baizhai Town and Qianhedao Village in Dahedao Town, etc., could be redeveloped according to township planning standards to prompt local urbanization for their high location potential capacity, high socioeconomic development, and large population. This type of rural residential land can also amalgamate nearby villages to form a larger one for uniformity in infrastructure, construction, and maintenance. Rural residential land belonging to modifying and expanding types can carry out self-service mode consolidation for their medium location potential capacity. With the help of village level industries, these rural residential land areas can compile their village plan to guide the demolition of unqualified buildings and construction of new residential land. Rebuilding type villages can be removed to larger villages or towns nearby to reduce the costs of municipal management. Vanishing type villages can be consolidated according to their future developing scenarios to realize diversified consolidation modes and methods, which also can be consolidated according to the adjacent village consolidation modes to conform to the feature of regional development. This research realizes the combination of location potential theory and rural residential land consolidation, which is helpful in the development and reconstruction of rural areas. The focus on the construction of urban centers of radiation and in-situ urbanization villages, control of the village-level self-service development village, guiding the development of backward dying villages, and relocation to integrate the five remediation modes were employed in this paper. The results showed that the regionalization project was optimal and reasonable, and the practicality of the model was verified. The paper, from the perspective of location for diversifying rural residential land of regulation, used a development model and adjusted measures to local conditions. The results reflect the current trend in rural residential land. This work could provide a new technique for rural residential land consolidation.
Number of references:34
Main heading:Rural areas
Controlled terms:Agriculture - Economic and social effects - Geographic information systems - Housing - Land use - Location - Mechanics - Potential energy - Regional planning - Zoning
Uncontrolled terms:Agricultural productions - Geographic information system software - Integrated development - Land consolidations - Modern infrastructure - Municipal managements - Socio-economic development - Traffic accessibilities
Classification code:971 Social Sciences - 931.1 Mechanics - 912 Industrial Engineering and Management - 911 Cost and Value Engineering; Industrial Economics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 723.3 Database Systems - 403 Urban and Regional Planning and Development
DOI:10.3969/j.issn.1002-6819.2013.10.034
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 29>

Accession number:20132516429396
Title:Estimation of regional evapotranspiration based on Penman-Monteith equation and soil moisture index
Authors:Sun, Liang (1); Chen, Zhongxin (1)
Author affiliation:(1) Key Laboratory of Agri-informatics, Ministry of Agriculture, Beijing 100081, China; (2) Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China
Corresponding author:Sun, L.(sunliang@caas.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:101-108
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Accurate calculation of land surface evapotranspiration is meaningful for the rational utilization of water resources. Penman-Monteith (PM) theory is a classic method to calculate evapotranspiration (ET) of land surfaces. Although Mu et al. (2011) improved ET estimates in Mu et al (2007) by adding nighttime ET and wet canopy surface ET component, it is difficult to acquire the 1km resolution spatial distribution of daily minimal air temperature (T<inf>min</inf>) for a regional scale, which is used as input variable (25km resolution) in Mu et al. (2007, 2011)'s global ET algorithms. Yuan et al. (2010)'s ET algorithm is modified from Mu et al (2007), they set invariant model parameters across the various vegetation types and T<inf>min</inf> is not used, therefore it is suitable for regional application. Soil resistance is largely controlled by the soil moisture. However, directly monitoring large scale soil moisture is always a challenge for remote sensing. In this study, we developed an ET estimation algorithm by incorporating a soil moisture index (SMI) derived from the improved surface temperature-vegetation cover feature space, denoted as the PM-SMI algorithm. The PM-SMI algorithm was compared with the triangle ET algorithm and another Penman-Monteith based algorithm (PM-Yuan) that calculated soil evaporation using relative humidity. Three ET algorithms were compared and validated by Bowen Ratio measurements at 12 sites in the Southern Great Plain (SGP) that were mainly covered by grassland and cropland with low vegetation cover. For instantaneous latent heat flux, although R² of PM-SMI was lower than that of triangle and PM-Yuan for some sites (EF2, EF4 and EF12), the RMSE and bias was the lowest across almost all the sites. PM-Yuan obviously underestimated LE with bias of -82.41 W/m². Triangle overestimated LE with 48.2 W/m². PM-SMI algorithm showed the best performance with RMSE, bias and R² of 53.67, 6.83 and 0.86 respectively. For daily latent heat flux, the bias of triangle was lower than PM-SMI for some sites, however, the RMSE was greater and R² was lower across almost all sites. Similarity, the R² of the PM-Yuan algorithm was greater for some sites, however the RMSE and bias was greater across almost all sites. Overall, the PM-SMI performed the best, with the highest R² (0.87) and the lowest RMSE (39.07 W/m²) and bias (-4.04 W/m²). The PM-Yuan algorithm significantly underestimated LE. The results showed that the PM-SMI algorithm performed the best among the three ET algorithms both on the instantaneous scale and the daily scale. PM-SMI is more reliable for estimation of ET over regional scale.
Number of references:25
Main heading:Algorithms
Controlled terms:Atmospheric temperature - Estimation - Evapotranspiration - Moisture - Soil moisture - Soils - Surface measurement - Vegetation - Water supply
Uncontrolled terms:Accurate calculations - Estimation algorithm - MODIS - Penman-Monteith - Penman-Monteith equations - Regional evapotranspiration - Soil moisture index - Southern great plains
Classification code:943.2 Mechanical Variables Measurements - 921 Mathematics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 483.1 Soils and Soil Mechanics - 446.1 Water Supply Systems - 444.1 Surface Water - 443.1 Atmospheric Properties
DOI:10.3969/j.issn.1002-6819.2013.10.014
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 30>

Accession number:20132516429410
Title:Combustion characteristics and combustion kinetics of agriculture biomass
Authors:Tian, Hong (1); Liao, Zhengzhu (1)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Guangdong University of Petrochemical Technology, Maoming 525000, China
Corresponding author:Tian, H.(honger8008@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:203-212
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to efficiently utilize agricultural biomass, thermogravimetry experimentation analysis of corn stalks, corn cobs, straw, lychee bar, and longan sticks and its mixed fuel was performed by using the TG-DTG-DSC (Thermogravimetric-Differential Thermogravimetric-Differential Scanning Calorimetry) thermal analysis technology. The combustible characteristics, ignition characteristics, burnout characteristics and synthetic combustion characteristics were investigated, and the combustion kinetics parameters were identified. The results show that the early burning DTG curves of corn stalks and corn cob have two peaks and three peaks, respectively, and the burning DTG curves of straw, longan sticks, and lychee strip each have only one peak. The mixed fuels prophase similar combustion characteristics of corn stalks, straw, and lychee bar show that the three fuels are suitable co-combustion. DSC curves of corn stalks S1 and straw S3 both have one endothermic peak late in the combustion, and the post-combustion needs to absorb more heat in order to maintain its combustion, which indicates that herbaceous biomass post-combustion stability is poor and not suitable for separate combustion. The DSC curve characteristics of wood-based biomass show that wood-based biomass has higher post-combustion stability. The combustible characteristics index and ignition characteristics index of corn stalks are both the largest, and their ignition temperature is the lowest, resulting in excellent pre-combustion performance. The burnout characteristic index of lychee bar is the largest and its burnout rate is the best, but its early combustion characteristics are not easy to catch fire and burn. The synthetic combustion characteristics of corncob are the best. The low-temperature phase of the reaction order is about 1.0-1.2, the high temperature phase of the reaction order is approximately 0.5-0.8, and the corresponding reaction activation energy is larger at the low temperature phase than that at the high temperature phase. The early biomass burning is a homogeneous fire and the late biomass burning belongs to a multiphase fire. The late stability of pure burning straw biomass is bad, but adding straw biomass with wood biomass is conducive to its pre-combustion of mixed fuels. The study results can provide guidance for the combustion and utilization of agricultural biomass.
Number of references:28
Main heading:Ignition
Controlled terms:Activation energy - Agriculture - Biomass - Combustion - Differential scanning calorimetry - Enzyme kinetics - Experiments - Kinetics - Precombustion - Thermoanalysis  - Thermogravimetric analysis - Wood fuels
Uncontrolled terms:Agricultural biomass - Characteristic indices - Combustion characteristics - High temperature phase - Ignition characteristics - Ignition temperatures - Low temperature phase - Scanning calorimetry
Classification code:931 Classical Physics; Quantum Theory; Relativity - 901.3 Engineering Research - 821.5 Agricultural Wastes - 931.3 Atomic and Molecular Physics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 524 Solid Fuels - 521.1 Fuel Combustion - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2013.10.028
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 31>

Accession number:20132516429414
Title:Modified method for gradation on agricultural land quality in land remediation project areas
Authors:Yu, Jianxin (1); Wei, Wei (2); Liao, Xiaohong (3); Peng, Yun (1); Liao, Lijun (1); Zhao, Yongli (1)
Author affiliation:(1) Engineering Lab. of the Yunnan Land Resources Utilization and Protection of Engineering Laboratory, Kunming 650201, China; (2) College of Resources and Environment, Yunnan Agricultural University, Kunming 650201, China; (3) College of Agronomy and Biotechnology, Yunnan Agricultural University, Kunming 650201, China; (4) Land Use-Field Base in Luliang County of Yunnan Province, Ministry of Land and Resources, Kunming 650201, China
Corresponding author:Yu, J.(yjxin58cn@yahoo.com.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:234-240
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Land remediation is an effective measure to improve land-use conditions and land quality. In the updated work of gradation on agricultural land quality, the existing gradation system cannot reflect the changes before and after land remediation projects. The paper proposes a new gradation system that can reflect the land quality changes before and after projects. The new gradation system adds two times of modification to the original gradation system. The first is to select the engineering factor of land remediation that influences the physical quality, obviously to calculate the modified coefficient of physical quality. The factors include terrain slope, outcrops of surface, probability of irrigation, and drainage condition. The second, select the land use factors which influence the utilization quality to calculate the modified coefficient of land use. These factors include regularity of plots, roads in croplands, patterns of irrigation, and patterns of drainage. Then the paper analyzed land remediation projects in Luliang County to verify the new gradation system. It selected 14 points that lay in the land remediation project areas. The results showed that: 1) Physical quality. 5 of 14 points' physical quality promoted a little, and the average promotion was 0.1 grades. The other 9 points did not change. 2) Utilization quality. Utilization quality of all the 14 points was promoted. The average promotion was 1.1 grades. The least was 0.5 grade and, the most was 1.7 grades. 3) Economic quality. Economic quality of all the 14 points was promoted. The average promotion was 1.1 grades. The least was 0.4 grade, and the most was 1.8 grades. It comes to a conclusion that: Taking the new gradation system of adding the modified coefficient of physical quality and the modified coefficient of land use to the original gradation system to be the gradation method for cultivated land in land remediation projects areas is feasible.
Number of references:26
Main heading:Land use
Controlled terms:Consolidation - Drainage - Grading - Irrigation
Uncontrolled terms:Agricultural land - Cultivated lands - Drainage condition - Effective measures - Engineering factors - Modified coefficient - Physical quality - Project areas
Classification code:821.3 Agricultural Methods - 502 Mines and Quarry Equipment and Operations - 483 Soil Mechanics and Foundations - 913.3 Quality Assurance and Control - 442 Flood Control; Land Reclamation - 403 Urban and Regional Planning and Development - 401 Bridges and Tunnels - 406 Highway Engineering
DOI:10.3969/j.issn.1002-6819.2013.10.032
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 32>

Accession number:20132516429405
Title:Differentiating profile based on single pig contour
Authors:Ma, Li (1); Ji, Bin (2); Liu, Hongshen (2); Zhu, Weixing (3); Li, Wei (2); Zhang, Tao (2)
Author affiliation:(1) Teachers' Ability Development Center, Anhui University of Technology, Ma'anshan 243032, China; (2) School of Computer Science, Anhui University of Technology, Ma'anshan 243032, China; (3) School of Electrical and Information Engineering, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Ji, B.(jibin@ahut.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:168-174
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The use and wide application of video monitoring and control systems in pig pens is necessary for the automation and analysis of intelligence to improve the development tendencies of the pig-raising industry. The complete profiling of a pig is convenient to behavior analysis and to judge if it is sick. A pig's wandering causes the lack of its full profile being captured on video. For example, only part of the body or no body at all in the image when intelligently monitoring a single pig in a pigpen will result in an abnormal profile. Not all profiles, or camera angles, of the pig are efficient for behavior analysis in the case that the pig's profile is not fully revealed, such as the pig directly facing the camera. Only scenes with the fully exposed profile of the pig are convenient for observing and analyzing the symptoms of the pig. Therefore, it is essential to automatically segment the video that is monitoring the pigpen. A novel method is proposed for setting the frame attributes based on the level of exposure to a pig's profile in a standing posture. Two types of attributes are presented for each frame in the video recording, which represent the applicable and non-applicable profile of a pig. A pig's profile feature vector is calculated for differentiating the attributes after obtaining a profile of a single pig by image processing. The vector is composed of both the aspect ratio of the pig's external shape and a group of low frequency Fourier coefficients based on the pig's contour. The aspect ratio varies with the angle between the axis of the pig body and the horizontal line on the left side of the ground. The result of the test shows that the aspect ratio index is ideal and plays a significant role only in both the acute angle areas, i.e., [-30&deg;, 30&deg;] and [-150&deg;, 150&deg;]. Eight low frequency Fourier coefficients are also verified enough to describe the characteristic shape of the pig body in reconstructing the profile image of a single pig by the Fourier inversion method. Means and variances of both the feature vectors of the applicable and non-applicable profile contours are obtained from the sample training set. The category of the unknown frame is identified by the Mahalanobis distance discrimination from the testing video. The results showed that 91.7% of frames in the pig's profile could be properly recognized. Therefore, this method of producing the frame attributes based on a single pig's contour is reliable. This study may be helpful for subsequently analyzing behavior of a single pig in suspected cases.
Number of references:28
Main heading:Mammals
Controlled terms:Aspect ratio - Cameras - Computer vision - Control system analysis - Cultivation - Fourier analysis - Image processing - Image retrieval - Video recording - Waveform analysis
Uncontrolled terms:Characteristic shapes - Development tendency - Fourier coefficients - Fourier inversion - Full contour - Mahalanobis distance discrimination - Profile - Single pig
Classification code:921 Mathematics - 821.3 Agricultural Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 742.2 Photographic Equipment - 943 Mechanical and Miscellaneous Measuring Instruments - 741.2 Vision - 731.6 Robot Applications - 731.1 Control Systems - 716.4 Television Systems and Equipment - 741 Light, Optics and Optical Devices
DOI:10.3969/j.issn.1002-6819.2013.10.023
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 33>

Accession number:20132516429391
Title:Thermal analysis of hydro-pneumatic suspension system for dumper based on a lumped-parameter thermal model
Authors:Huang, Xiaxu (1); Shen, Yanhua (1); Yang, Jue (1); Zhang, Wenming (1)
Author affiliation:(1) School of Mechanical Engineering, University of Science and Technology Beijing, Beijing 100083, China
Corresponding author:Shen, Y.(yanhua_shen@ces.ustb.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:64-70
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Hydro-pneumatic suspension is an important part of off-highway dump trucks. It represents a compromise between ride comfort and handling stability via its nonlinear character. Off-highway dump trucks generally use the single air chamber hydro-pneumatic suspension system to achieve a vehicle's reliability and economy. But the effect of temperature changes on the output force characteristics of the hydro-pneumatic suspension, which results in ride comfort and ride height, is one of the urgent problems in its design and use. This paper presents a thermodynamic study of the hydro-pneumatic suspension using a lumped parameter model. It is known that this method is used to solve thermal problems by analyzing thermal networks by analogy to electrical circuits. This method has been used for a long time to calculate the temperature rises in electrical and spacecraft systems. Different from other studies, the cylinder and the piston rod thermal capacitance are taken into consideration in this study. During the study, the suspension system is divided into a number of lumped components. Each component has a thermal storage and interconnections to neighbor components through a linear mesh of thermal resistances. The heat is generated by oil flows through the damping orifices and nitrogen compression. Then, based on the gas state equation and thermodynamic theory, the nonlinear equations of the thermal model are established, which originally contain the heat capacity of the cylinder, the piston, and the oil. The simulation analysis is carried out under the model. The results show that, except for the oil in the bottom of the piston rod, while considering the thermal capacitance of the cylinder and piston, the temperature of the suspension system rises slower than if those capacitances are ignored. A validation experiment is performed to confirm the predicted results. The oil temperature in the initial stage of the experiment decreased first and then increased, which is different from the calculated value's monotonically upward trend. This may be caused by the fact that the oil from the static to flow requires a certain amount of energy in the initial stage of the experiment, while the external input of energy is shortage. Due to the measurement error, the lack of detail in lumped element division, and some other reasons, there are some differences between the experimental data and calculated values, but the tendencies of the experimental and calculated temperature rise of the suspension system are the similar. The comparison results show that the proposed model can describe the thermodynamic state of the hydro-pneumatic suspension more accurately than previous methods. The thermal capacitance of the cylinder and piston will increase the hysteresis effect of temperature changes.
Number of references:21
Main heading:Pneumatic control
Controlled terms:Capacitance - Computer simulation - Cylinders (shapes) - Electric network analysis - Equations of state - Experiments - Heat problems - Heat storage - Suspensions (components) - Suspensions (fluids)  - Temperature - Thermoanalysis - Thermography (temperature measurement) - Trucks
Uncontrolled terms:Effect of temperature - Handling stabilities - Hydro-pneumatic suspension - Lumped parameter - Lumped parameter models - Nonlinear characters - Off-highway dump trucks - Thermodynamic studies
Classification code:723.5 Computer Applications - 731.1 Control Systems - 801 Chemistry - 804 Chemical Products Generally - 901.3 Engineering Research - 921 Mathematics - 944.6 Temperature Measurements - 703.1.1 Electric Network Analysis - 408.2 Structural Members and Shapes - 601.2 Machine Components - 641.1 Thermodynamics - 641.2 Heat Transfer - 651.1 Aerodynamics, General - 663.1 Heavy Duty Motor Vehicles - 703.1 Electric Networks
DOI:10.3969/j.issn.1002-6819.2013.10.009
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 34>

Accession number:20132516429409
Title:Gasification property of agriculture wastes in an updraft fixed bed gasifier with top-lit ignition
Authors:Zhang, Shihong (1); Li, Xiangpeng (1); He, Guangchang (1); Yang, Haiping (1); Wang, Xianhua (1); Chen, Hanping (1)
Author affiliation:(1) State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China
Corresponding author:Zhang, S.(shzhang@mail.hust.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:196-202
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The gasification behavior of agriculture waste was investigated using a Top-lit Up Draft (TLUD) fixed-bed gasifier system which consists of four subsystems (gasifier reaction system, temperature monitor system, tar sampling system, and gas measurement system), in an attempt to find out the influence of air flow on the gasifier's temperature distribution, gas component, and heating value, and discuss the gasification mechanism of biomass. In the study, peanut shells and rice husks were chosen as experiment material. The reactor is made from &Phi;219 mm&times;6 mm stainless steel pipe with length of 800 mm. After the reactor filled up with sample materials (about 3.5 kg), a certain amount of air (range from 2.5 m³/h to 4.0 m³/h) was pumped in at the bottom, and the sample was lit at the top. The temperature was then tested by a temperature monitoring system, and the gas product was detected by a Gasboard-3100P-type multi-component portable infrared gas analyzer (Quartet Photoelectric Technology Co., Ltd. Wuhan, China), and the tar was collected by a tar sampling system. From the results of the investigation, the gasification process lasted about 100 min, and was divided into two stages. First, the main reaction was biomass drying, volatile releasing, and char gasification, and the main gas products were CO<inf>2</inf>, CO, H<inf>2</inf>, and CH<inf>4</inf>. About 50 min later, it went into the second stage, and the oxidization of solid char residue played a major role in the gasifier with a large amount of CO production. Throughout the whole reaction, the heating value of gas products was a minimum of 3 MJ/m³, and the evolution of the gasfier temperature profile was very similar with that of wave propagation. During the first stage of gasification, the maximum temperature of the gasifier was 730&deg;C; when it switched into the second stage, the main reaction occurred at the bottom, and the max temperature would rise up to 1000&deg;C. The airflow rate can be converted to the Air/Fuel equivalence ratio (ER), the most important aspect of gasifier operation. ER had great influence on biomass gasification property, and higher ER was favorable for the enhancing of gas yield, however, it had different effects on the releasing of flammable gas (CO and H<inf>2</inf>). The optimum gasfication condition was achieved when ER is 0.31 and 0.35 for peanut shell and rice husk, respectively, and the tar content of gas is very low (as low as 0.25g/m³ and 0.49g/m³, respectively). This study would be helpful to the design and operation of TLUD fixed-bed gasifiers.
Number of references:29
Main heading:Gasification
Controlled terms:Agricultural wastes - Biomass - Carbon dioxide - Gases - Oilseeds - Polymer blends - Tar - Temperature distribution - Wastes - Wave propagation
Uncontrolled terms:Equivalence ratios - Gasifiers - Peanut shells - Rice husk - Top-Lit
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 821.5 Agricultural Wastes - 821.4 Agricultural Products - 816.1 Processing of Plastics and Other Polymers - 804.2 Inorganic Compounds - 804 Chemical Products Generally - 802.3 Chemical Operations - 711 Electromagnetic Waves - 641.1 Thermodynamics - 524 Solid Fuels - 513 Petroleum Refining - 452.3 Industrial Wastes - 411 Bituminous Materials
DOI:10.3969/j.issn.1002-6819.2013.10.027
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 35>

Accession number:20132516429420
Title:Succinylation improves structure and hydrophobicity of yak casein micelles
Authors:Yang, Min (1); Liang, Qi (1); Bi, Yang (1); Wen, Pengcheng (1); Zhang, Weibing (1); Yang, Jitao (3)
Author affiliation:(1) College of Food Science and Engineering, Gansu Agricultural University, Lanzhou 730070, China; (2) Functional Dairy Product Engineering Lab of Gansu, Lanzhou, 730070, China; (3) College of Science, Gansu Agricultural University, Lanzhou, 730070, China
Corresponding author:Yang, M.(yangmin@gsau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:287-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Yak caseins are special materials whose structures are different from cow caseins. Chemical modification is commonly applied to improve the functional properties of food proteins, such as acylation, succinylation, esterification, oxidation, reduction, glycosylation, phosphorylation, and alkylation. Succinylation is a useful method for significantly improving the functional properties of protein; iexhaustive succinylation induces large changes in physio-chemical properties of caseins, particularly in their electrostatic nature. However, very little literature is available about the structures, physio-chemical, and functional properties of yak caseins to direct industry processing of yak caseins. The present work tested the influence of succinylated modification on the structure and hydrophobicity of yak casein micelles. The spatial structure of modified and unmodified yak casein micelles were studied by Fourier transformation infrared spectroscopy. The diameter of modified and unmodified casein micelles was detected by dynamic light scattering and its surface morphology was observed by scanning electron microscope. The results showed that the spatial structure contents of &beta;-turn, irregular, &beta;-sheet, and large loop in yak casein micelles were 33.1%, 23.2%, 32.0%, and 11.7% respectively, while &alpha;-helix was not detected. After succinylated modification, a certain amount of amino changed into the amide linkage, the charge of side chain changed from positive charge into negative charge, the repulsion between side chain groups decreased, and &alpha;-helix was formed with content of 12.4%. The modification has slight influences on the other spatial structures except &alpha;-helix. Succinylation treatment induced the dissociation of caseins from the micelles, the size of yak casein micelle was decreased, and the shape of casein micelles was changed from irregular spherical into a sphere. After succinylation, lysine changed to succinamoyl groups and the electrostatic ionic interactions among ANS and caseins decreased, resulting in decreasing numbers of ANS molecules bounded to casein micelle. Thus, the fluorescence intensity of ANS decreased in casein solution. The maximum emission wavelength (&lambda;max) was very useful in estimating the hydrophobicity of the microenvironment around tryptophan residues. By succinylation, many -NH2 in caseins were effectively changed to carboxylic groups from succinic anhydride, and the hydrogen bonds formed by -NH2 were destroyed. At pH of 7.0, the deprotonation of the carboxylic groups gave rise to many changes in casein micelle formation, including electrostatic repulsions and hydrogen bonds and the destruction of salt bridges, eventually leading to the loose structure of the casein micelle. Therefore, the tryptophan residues were located at less hydrophobic micro domain areas in casein micelles with succinylation, which led to the increase of the maximum emission wavelength and the decrease of fluorescence intensity in steady-state fluorescence emission spectra. To sum up, the hydrophobicity of yak casein declined significantly by succinylation. The results could provide references for the chemical modification of yak casein.
Number of references:29
Main heading:Casein
Controlled terms:Amino acids - Chemical modification - Chemical properties - Electrostatics - Emission spectroscopy - Esterification - Fluorescence - Fourier transforms - Hydrogen bonds - Hydrophobicity  - Infrared spectroscopy - Micelles - Proteins - Scanning electron microscopy - Space applications
Uncontrolled terms:Electrostatic repulsion - Fluorescence intensities - Fourier transformations - Micellar structures - Physio-chemical properties - Scanning Electron Microscope - Steady-state fluorescence - Succinylation
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 921.3 Mathematical Transformations - 804.1 Organic Compounds - 802.2 Chemical Reactions - 801 Chemistry - 741.1 Light/Optics - 701.1 Electricity: Basic Concepts and Phenomena - 656 Space Flight - 423 Non Mechanical Properties and Tests of Building Materials
DOI:10.3969/j.issn.1002-6819.2013.10.038
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 36>

Accession number:20132516429392
Title:Soft sensor of vehicle side slip angle based on Kalman filter
Authors:Shen, Fapeng (1); Zhao, Youqun (1); Lin, Fen (1)
Author affiliation:(1) Department of Automotive Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China; (2) Shandong Transport Vocational College, Weifang 261206, China
Corresponding author:Zhao, Y.(yqzhao2@yahoo.com.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:71-75
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Vehicle electronic control systems effectively improve vehicle stability performance by controlling the key parameters of the moving vehicle. The premise and necessary conditions to improve stability performance is to accurately measure of the stated vehicle parameters, which can reflect the vehicle changes in the control process. Yaw rate and vehicle sideslip angle are important parameters to the vehicle control system; the former can be directly measured through the corresponding sensors, while the latter is difficult or expensive to directly measure. Usually, vehicle sideslip angle is estimated by other vehicle parameters, such as vehicle longitudinal velocity and lateral velocity, etc. One is too direct integral method to calculate vehicle sideslip angle, but the noise signal is also involved in the integration process, and can cause greater errors. Another is to use GPS/INS and gyroscopes to measure, but the cost is too high to promote. In addition, some soft sensors based on state estimation have good applications in the field. To solve the problem that vehicle sideslip angles in the vehicle control process is too difficult to measure on-line, the soft sensor model is established with a Kalman filter and driver-vehicle closed-loop system, based on parameters of soft sensor theory and discrete signal filtering theory. This measurement can realize the on-line inference and estimation of sideslip angles by using yaw rate and lateral acceleration, which are easy to measure. Thus, the soft sensor of sideslip angles is achieved through state estimation. Based on the preview optimal control theory of curvature and the preview follow theory, the soft sensor model was developed by a two degree of freedom driver-automobile closed-loop system model. Its' state equation and observation equation have been derived and discrete to draw the system discrete observation equation on the observation quantity of yaw rate and lateral acceleration and to do the simulation. To compare estimated value with test value, the researchers conducted road tests. One test was the double lane change (standard: ISO 3888-1999-1), the other was a slalom (standard: GB/T 6323.1-1994); these tests obtained the data of longitudinal velocity, lateral velocity, yaw rate, lateral acceleration, and vehicle sideslip angle. The values of yaw rate and lateral acceleration are collected real-time by a DMS-SGP01 gyroscope, and the values with noise are the input measurements of the state estimation by a kalman filter. Other values are collected by non-contact velocity meter systems that consist of LC-761, LC-1100, LC-2100, and LC-5200. The LC-1100, which is a longitudinal velocity sensor, and the LC-2100, which is a lateral velocity sensor, are spatial filter types used to collect the values of longitudinal velocity and lateral velocity. The values of sideslip angle are measured by using LC-5200 forward distance pulse in the system. The results of the values' comparison show that there are the same changing trends and error within 10% of the test value amplitude. It is shown that the soft sensor can achieve the precise estimation results of the vehicle sideslip angle and is feasible. The realization of state estimation based on soft sensor technology provides a theoretical basis on soft sensors applied to vehicle stability control systems.
Number of references:29
Main heading:Vehicles
Controlled terms:Closed loop systems - Control system synthesis - Control systems - Equations of state - Gyroscopes - Kalman filters - Process control - Seats - Sensors - Sensory perception  - State estimation - Testing - Velocity
Uncontrolled terms:Direct integral method - Longitudinal velocity - Optimal control theory - Sideslip angles - Soft sensors - Two-degree of freedom - Vehicle control system - Vehicle stability control systems
Classification code:931.1 Mechanics - 921 Mathematics - 801 Chemistry - 731.1 Control Systems - 943.1 Mechanical Instruments - 731 Automatic Control Principles and Applications - 461.4 Ergonomics and Human Factors Engineering - 432 Highway Transportation - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 461.5 Rehabilitation Engineering and Assistive Technology
DOI:10.3969/j.issn.1002-6819.2013.10.010
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 37>

Accession number:20132516429402
Title:Root distribution features of typical herb plants for slope protection and their effects on soil shear strength
Authors:Li, Jianxing (1); He, Binghui (1); Chen, Yun (1); Huang, Ru (1); Tao, Jun (1); Tian, Taiqiang (1)
Author affiliation:(1) College of Res. and Environ./Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Southwest University, Chongqing 400715, China
Corresponding author:He, B.(hebinghui@swu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:144-152
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Plant root systems play an important role in soil erosion control. To investigate characteristics of root systems of herb vegetation for erosion control in the Three Gorges Reservoir region and their influences on soil shear strength, we used bare land as a control. Four typical herb plants of erosion control, Vetiveria zizanioides (Lin.) Nash, Paspalum notatum Flugge, Cynodon dactylon (L) Pers. and Medicago sativa L., were selected and investigated in the experiments. Circular knives (base area: 30 cm², high: 10 cm) were used to take samples from the test area for analysis. Direct shear apparatus was applied to analyze soil shear strength. A root analysis system (WinRHIZOPro.2004c) was used to characterize the root systems. The results indicated that: 1) Vetiveria zizanioides (Lin.) Nash had the largest root length density and root surface area density. 2) Root length density, root surface area density, and root weight density of all typical herb plants were decreased with the increasing of soil depth, but the difference on root length density, root surface area density, and root weight density among different herb plants was not significant with the increasing soil depth. The root length density, root surface area density, and root weight density were 0.92 cm/cm³, 0.29 cm²/cm³, and 2.10 mg/cm³ for Cynodon dactylon (L) Pers., 1.01 cm/cm³, 0.77 cm²/cm³ and 34.72 mg/cm³ for Medicago sativa L., 8.12 cm/cm³, 3.12 cm²/cm³ and 27.70 mg/cm³ for Vetiveria zizanioides (Lin.) Nash and 1.66 cm/cm³, 0.71 cm²/cm³ and 9.26 mg/cm³ for Paspalum notatum Flugge, respectively. 3) Soil shear strength was significantly different in the 4 herb plants. Even in the same herb plant, it had different patterns with the difference of soil layers. The internal friction angle &phi; and cohesion c declined with the increasing of soil depth. We found that the internal friction angle &phi; and cohesion c of all herb plants were higher than that of bare land. The sequence from high to low were: Vetiveria zizanioides (Lin.) Nash&gt;Paspalum notatum Flugg&gt;Medicago sativa L. &gt;Cynodon dactylon (L) Pers. 4) The internal friction angle &phi;, cohesion c, and shear displacement were 14.79&deg;, 15.96 kPa, and 3.43 mm for Cynodon dactylon (L) Pers., 17.44&deg;, 20.93 kPa and 4.89 mm for Medicago sativa L., 24.04&deg;, 31.36 kPa and 2.88 mm for Vetiveria zizanioides(Lin.) Nash and 18.71&deg;, 30.34 kPa and 3.63 mm for Paspalum notatum Flugge and 9.45&deg;, 14.18 kPa and 5.51 mm for bare land, respectively. 5) The internal friction angle &phi; was logarithmic growth and cohesion c was linear growth with the increase of root length density and root surface area density, and soil shear strength had an obvious correlation relationship with root systems when the diameter was less than 5 mm. It is concluded that root length density and root surface area density are the best indexes to characterize soil shear strength, especially root length density and root surface area density of roots with D&le5 mm. The results will be useful for hillslope vegetation protection and soil erosion control.
Number of references:24
Main heading:Shear strength
Controlled terms:Adhesion - Density (specific gravity) - Erosion - Forestry - Internal friction - Soil conservation - Soils - Vegetation
Uncontrolled terms:Direct shear apparatus - Herb plants - Internal friction angle - Root length density - Root surfaces - Shear displacement - Three Gorges Reservoir region - Vegetation protection
Classification code:821.0 Woodlands and Forestry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 483.1 Soils and Soil Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids - 483 Soil Mechanics and Foundations - 421 Strength of Building Materials; Mechanical Properties - 407 Maritime and Port Structures; Rivers and Other Waterways - 422 Strength of Building Materials; Test Equipment and Methods
DOI:10.3969/j.issn.1002-6819.2013.10.020
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 38>

Accession number:20132516429419
Title:Comparison of sensory quality between subjective evaluation and instrument detection for cucumber juice with high pressure processing and heat treatment
Authors:Wang, Chunfang (1); Mao, Ming (1); Hu, Feifei (1); Yu, Yong (1); He, Jinsong (1); Zhu, Songming (1)
Author affiliation:(1) College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
Corresponding author:Yu, Y.(yyuzju@zju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:10
Issue date:May 15, 2013
Publication year:2013
Pages:278-286
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:High pressure processing is an alternative technique for thermal treatment of foods for sterilization, enzyme inactivation, protection of sensory quality and so on. Many studies have showed that there were different effects of high pressure processing on sensory quality for different kinds of juice. This study was focus on two aspects. One is to study the sensory quality protective capability of high pressure processing for cucumber juice. The other is to study the difference of artificial and instrument evaluation on sensory quality and confirm the reliability of instrument evaluation. The Cucumber juice samples were obtained after cleaning, squeezing and centrifugation in sterile conditions. Then the juice was treated with high pressure at 500 MPa for 2 min or 600 MPa for 2 min, and with heat at 60&deg;C for 2 min. After treatment, the samples were stored at 10, 25 and 37&deg;C for 15 d, 64 h and 24 h respectively. And the sensory quality evaluations were carried on at 0, 1, 3, 7, 10 and 15 d for 10&deg;C storage, every 8 h for 25&deg;C storage and every 4 h for 37&deg;C storage. The instrument evaluation include chromatic meter combined with &Delta;E (color evaluated), centrifugal settling quality (precipitation evaluated) and characteristic smells content analysis (with GC-MS for smell evaluate). The artificial evaluation was conducted by a panel of 6 experts trained before formal evaluated. The Pearson correlation analysis was used for confirm the reliability of instrument evaluation. The results showed that there was no obvious difference among the cucumber juice with different treatments on the value of color and smell. During the storage, the total color difference (&Delta;E) was increased with the time of storage at three store temperatures, and the increasing extent and the final value were similar for the two treatments. The same results obtained in mass fraction of trans-2-cis-6-Nonadienal, acetaldehyde and trans-2-Hexenal. During the storage at 10&deg;C, the centrifugal settling quality of the sample with high pressure treatment was significant lower than that of sample with heat treatment, and this advantage was not significant with the increasing store temperature. Thus, the 10&deg;C was suitable for cucumber juice store. The correlation analysis on artificial and instrument evaluation showed that there was significant correlation between chromatic meter combined with &Delta;E and artificial evaluation. This instrument evaluation for color was available for the samples stored at 10, 25 and 37&deg;C. There was significant correlation between centrifugal settling quality and its artificial evaluation for the samples stored at 25 and 37&deg;C, but this instrument evaluation for settling quality wasn't available for the samples stored at 10&deg;C. There was significant correlation between trans-2-cis-6-Nonadienal and trans-2-Hexenal and their artificial evaluations for the samples stored at 10&deg;C, and this instrument evaluation for smell was available for 10&deg;C storage.
Number of references:22
Main heading:Quality control
Controlled terms:Centrifugation - Color - Energy storage - Heat treatment - High pressure effects - Instruments - Quality management
Uncontrolled terms:Cucumber juice - Different treatments - High pressure processing - High pressure treatments - Pearson correlation analysis - Sensory qualities - Subjective evaluations - Total color difference
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 931.2 Physical Properties of Gases, Liquids and Solids - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 913.3 Quality Assurance and Control - 741.1 Light/Optics - 702 Electric Batteries and Fuel Cells - 537.1 Heat Treatment Processes - 802.3 Chemical Operations
DOI:10.3969/j.issn.1002-6819.2013.10.037
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.