|
2012年第43卷第11期共收录48篇 1. Accession number:20125115822662 Title:Flow characteristic experiment of solenoid valve region for high-pressure fuel system Authors:Qiu, Tao1 ; Lei, Yan1 ; Peng, Jing1 ; Li, Xuchu1 Author affiliation:1 College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China Corresponding author:Qiu, T. (qiutao@bjut.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:7-10 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The flow characteristics of solenoid valve region of electronic unit pump (EUP). EUP was rebuilt by using optical visualization observation. A diaphanous glass window was designed in the pump, and the transient flow in the solenoid valve outlet was observed by a high-speed camera. By gray processing of pictures, the brightness curve within the control valve region was acquired. Results showed that cavitation occurred in control valve of EUP and formed the two phase flow phenomenon. The formation of cavitation had two factors, one was due to flow region in control valve where high-speed fuel flow within was quiet narrow, another reason was that the control valve hit the baffle which caused vibration and impingement, hence the fuel was extruded. Number of references:10 Main heading:Two phase flow Controlled terms:Cavitation - Diesel engines - Pumps - Safety valves - Solenoid valves Uncontrolled terms:Control valves - Electronic unit pump (EUP) - Flow characteristic - Flow regions - Fuel flow - Glass windows - In-control - Optical visualization - Transient flow Classification code:612.2 Diesel Engines - 618.2 Pumps - 619 Pipes, Tanks and Accessories; Plant Engineering Generally - 619.1.1 Pipe Accessories - 631.1 Fluid Flow, General - 631.1.1 Liquid Dynamics DOI:10.6041/j.issn.1000-1298.2012.11.002 Database:Compendex 2. Accession number:20125115822683 Title:Improvement of SST k-ω turbulence model and numerical simulation in centrifugal pump Authors:Ren, Yun1 ; Liu, Houlin1 ; Shu, Minhua2 ; Wu, Xianfang1 ; Wu, Denghao1 Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China 2 Naval Architecture, Ocean and Civil Engineering, Shanghai Jiao Tong University, Shanghai 200240, China Corresponding author:Liu, H. (liuhoulin@ujs.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:123-128 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The advantages and disadvantages of several commonly turbulence model in centrifugal pump inner flow simulation were analyzed. Two new models based on SST k-ω turbulence model were improved with considering the effects of rotation and curvature. The procedures of new models were implemented on the open source code OpenFOAM. Simultaneously, the new turbulence models were adopted to simulate the inner flow in a centrifugal pump with different specific speeds under different operating points. Lastly, comparisons were made with experimental results and the numerical results from the original and modified models. The results showed that the modified models could calculate the inner flow of centrifugal pump successfully, and energy performance by new models was closer to experimental results than that of original model. Number of references:15 Main heading:Computer simulation Controlled terms:Centrifugal pumps - Turbulence models Uncontrolled terms:Effects of rotation - Energy performance - Inner flow - Modified model - Numerical results - Open-source code - OpenFOAM - Operating points - Original model - Specific speed Classification code:443.1 Atmospheric Properties - 618.2 Pumps - 723.5 Computer Applications DOI:10.6041/j.issn.1000-1298.2012.11.023 Database:Compendex 3. Accession number:20125115822696 Title:Design of ZigBee-based greenhouse environmental monitoring image sensor node Authors:Zhao, Chunjiang1 ; Qu, Lihua2 ; Chen, Ming2 ; Yang, Xinting1 ; Sun, Chuanheng1 ; Li, Wenyong1 Author affiliation:1 National Engineering Research Center for Information Technology in Agriculture, Beijing 100097, China 2 College of Information Technology, Shanghai Ocean University, Shanghai 201306, China Corresponding author:Zhao, C. (zhaocj@nercita.org.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:192-196 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:A wireless intelligent image sensor node was designed. The hardware processing platform combined chip CC2430 and LPC1766. Image frame, which was collected by the serial camera, was divided into many packets which were transmitted through ZigBee protocol one by one. The experiment results showed that the node's maximum communication distance was 160 m, and the node packet loss rate was low. In addition, the JPEG format image acquired by camera was about 10 kB which takes 135 s to transmit via ZigBee. The designed node, with compact structure, stability work condition and low power consumption, could realize acquisition and transmission of the greenhouse environment information. So, it can meet the need of the greenhouse environment monitoring. Number of references:14 Main heading:Sensor nodes Controlled terms:Cameras - Environmental engineering - Greenhouses - Image sensors - Wireless sensor networks - Zigbee Uncontrolled terms:Communication distance - Compact structures - Environmental Monitoring - Greenhouse environment - Image frames - Intelligent image sensor - Low-power consumption - Packet loss rates - Processing platform - Work condition Classification code:402.1 Industrial and Agricultural Buildings - 454 Environmental Engineering - 722 Computer Systems and Equipment - 722.3 Data Communication, Equipment and Techniques - 741.3 Optical Devices and Systems - 742.2 Photographic Equipment DOI:10.6041/j.issn.1000-1298.2012.11.036 Database:Compendex 4. Accession number:20125115822685 Title:Influence of dip angle changing on meridian velocity for screw centrifugal pump Authors:Li, Rennian1 ; Deng, Yuxuan1 ; Han, Wei1 ; Yang, Wenjie1 Author affiliation:1 School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou 730050, China Corresponding author:Li, R. (lirn@lut.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:134-137 133 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:According to the different movement characters of screw segment and centrifugal segment of liquid-solid two-phase flow in the screw centrifugal impeller and the structure characters of screw centrifugal pump impeller, the vane profile parameter equation group for variable-dip screw centrifugal pump was derived. The meridian velocity distribution can be changed though changing some parameters of the vane profile parameter equation group. Thus the better meridian velocity distribution could be found by using this method. Using the parameter equation group, the CAD and numerical simulation of 3-D flow field were also facilitated for screw centrifugal pump. Number of references:11 Main heading:Screws Controlled terms:Centrifugal pumps - Centrifugation - Impellers - Liquids - Two phase flow Uncontrolled terms:Centrifugal impeller - Centrifugal pump impellers - Dip angle - Liquid-solid two phase flow - Parameter equations - Structure character - Vane profile Classification code:601.2 Machine Components - 605 Small Tools and Hardware - 618.2 Pumps - 631.1 Fluid Flow, General - 802.3 Chemical Operations - 931.2 Physical Properties of Gases, Liquids and Solids DOI:10.6041/j.issn.1000-1298.2012.11.025 Database:Compendex 5. Accession number:20125115822676 Title:Experiment on crop coefficient and water requirement of drip-irrigation jujube in loess plateau of China Authors:Hu, Yongxiang1 ; Li, Yuannong1 ; Zhang, Ying2 Author affiliation:1 College of Water Resources and Architectural Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China 2 School of Foreign Language, Hebei University of Science and Technology, Shijiazhuang 050018, China Corresponding author:Li, Y. (liyuannong@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:87-91 79 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The experimental area located in Mizhi experimental station in loess plateau of China. According to the meteorological data observed by automatic weather station of Mizhi experimental station and using FAO Penman-Montieth equation, the crop reference evapotranspiration was calculated consequently in jujube's growth period. Additionally, combined with crop evapotranspiration of jujubes under sufficient irrigation, the crop coefficient of drip-irrigation jujubes was studied. The water requirements and crop coefficient was determined in each growing period of jujube. Water requirements (crop evapotranspiration) in sprout-leaf development period, flowering and fruit-setting period, fruit development period and fruit development period was 68.1mm, 117.4 mm, 224.4 mm and 66.2mm, respectively. Crop coefficient in each growth period was as follows: 0.496 in sprout-leaf development period, 0.681in flowering and fruit-setting period, 1.262 in fruit development period, and 0.944 in fruit mature period. A function relationship was established between crop coefficient and leaf area index, and the results demonstrated that there was a quadratic curve relationship between crop coefficient and leaf area index. Number of references:12 Main heading:Crops Controlled terms:Evapotranspiration - Fruits - Irrigation - Landforms - Meteorology - Water supply Uncontrolled terms:Automatic weather stations - Crop coefficient - Crop evapotranspiration - Drip-irrigation - Experimental stations - Fruit development - Function relationships - Growing period - Growth period - Jujube - Leaf Area Index - Loess Plateau - Meteorological data - Quadratic curves - Reference evapotranspiration - Water requirements Classification code:443 Meteorology - 444.1 Surface Water - 446.1 Water Supply Systems - 481.1 Geology - 821.3 Agricultural Methods - 821.4 Agricultural Products DOI:10.6041/j.issn.1000-1298.2012.11.016 Database:Compendex 6. Accession number:20125115822703 Title:Agricultural machinery trace monitoring system with Google Maps Authors:Shi, Guobin1 ; Wang, Xi2 ; Zhuang, Weidong2 Author affiliation:1 College of Information Technology, Heilongjiang Bayi Agricultural University, Daqing 163319, China 2 College of Engineering, Heilongjiang Bayi Agricultural University, Daqing 163319, China Corresponding author:Wang, X. (ndwangxi@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:231-236 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:To meet the needs of modern agricultural machinery management, an agricultural machinery trace monitoring system based on the technology of GPS, GPRS and Google Maps was developed in order to realize the real-time monitoring and scheduling of farm machinery. This system with built-in GPS and GPRS modules, which use wireless network transfer GPS data to remote machine by single-chip microcomputer. With Google Maps API, a Web GIS system was established. An agricultural machinery management by ASP.NET was achieved. Web Service and Ajax technology was used to do such things like trace playback, length measuring, and calculation of land area function. Number of references:16 Main heading:Agricultural machinery Controlled terms:Monitoring - Scheduling - Web services - Websites Uncontrolled terms:AJAX technology - ASP.NEt - Farm machinery - Google maps - GPRS module - GPS data - Land areas - Monitoring system - Real time monitoring - Remote machines - Single chip microcomputers - Trace - Web-GIS Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 912.2 Management - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 821.1 Agricultural Machinery and Equipment - 718 Telephone Systems and Related Technologies; Line Communications - 717 Optical Communication - 716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications DOI:10.6041/j.issn.1000-1298.2012.11.043 Database:Compendex 7. Accession number:20125115822705 Title:Numerical simulation of cavitating flow in water hydraulic axial piston pump Authors:Zhai, Jiang1 ; Zhao, Yonggang2 ; Zhou, Hua1 Author affiliation:1 The State Key Lab of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China 2 707 Research Institute of CSIC, Jiujiang 332007, China Corresponding author:Zhou, H. (hzhou@sfp.zju.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:244-249 260 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to study the cavitation characteristics of a water hydraulic axial piston pump, cavitating flow in the pump was simulated based on Schnerr-Sauer model. The fluctuations of flow and pressure at the outlet of the pump were analyzed at different inlet pressure conditions. From the simulation results, it is concluded that obvious cavitations occur in the cylinder chambers which are in suction process. Cavitation regions are mainly located in the sides near to the rotation center, and more serious cavitations occur in the piston chamber which contact with the suction side of the portplate. Dynamic pulsation of flow rate and pressure at the outlet of pump are more severe when serious cavitations occur. Cavitations can be reduced if the pressure at the inlet of pump is increased, but excessive pressure at the inlet can induce pressure pulse in piston chamber which in suction region. When cavitations are decreased to some degree, dynamic pulsation of flow rate and pressure of pump can not be impacted obviously by the pressure at the inlet. Number of references:12 Main heading:Cavitation Controlled terms:Computer simulation - Flow rate - Inlet flow - Optical pumping - Reciprocating pumps Uncontrolled terms:Axial piston pump - Cavitating flow - Cylinder chambers - Inlet pressures - Pressure pulse - Pulsation - Rotation centers - Suction process - Suction side - Water hydraulics Classification code:618.2 Pumps - 631 Fluid Flow - 723.5 Computer Applications - 741.1 Light/Optics DOI:10.6041/j.issn.1000-1298.2012.11.045 Database:Compendex 8. Accession number:20125115822682 Title:Relationship of performances and design parameters for non-overload centrifugal pumps Authors:Yang, Junhu1 ; Guo, Bin1 ; Wang, Yue1 ; Zhang, Yunzhou1 ; Meng, Ruifeng1 ; Wang, Xiaohui1 Author affiliation:1 School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou 730050, China Corresponding author:Yang, J. (lzyangjh@lut.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:119-122 128 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:According to the formula of the ratio K of the maximal axle power to the rated axle power of the non-overload centrifugal pumps, K was expressed as the function of specific speed, impeller outlet angle and number of blades by calculating the formula. The three-dimensional image of K and contours about specific speed and impeller outlet angle of K under different numbers of blades were drawn based on the function. K is not close to the number of blades; while the impeller outlet angle and specific speed have a greater effect on K. Under the same K, the higher the specific speed was, the bigger the impeller outlet angle would be. Reasonable impeller outlet angle can be chosen according to the specific speed and K from the contours. The example showed that the method can make the design of non-overload centrifugal pumps successfully and quickly, and can avoid the blindness in choosing the impeller outlet angle with the traditional method. Number of references:10 Main heading:Flow measurement Controlled terms:Axles - Centrifugal pumps - Large scale systems - Speed Uncontrolled terms:Design parameters - Impeller outlet - Non-overload - Power spare coefficient - Specific speed - Three dimensional images Classification code:618.2 Pumps - 682.1.1 Railroad Cars - 931.1 Mechanics - 943.2 Mechanical Variables Measurements - 961 Systems Science DOI:10.6041/j.issn.1000-1298.2012.11.022 Database:Compendex 9. Accession number:20125115822684 Title:Prewhirl regulation experiment of inlet guide vane for centrifugal pump based on Gottingen airfoil Authors:Wang, Haimin1 ; Lin, Hao1 ; Huang, Xiong1 ; Zhou, Caimin1 Author affiliation:1 School of Energy and Power Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China Corresponding author:Wang, H. (hmwang@usst.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:129-133 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The guide vanes were designed by using the axial flow pumps isolated blade design method based on Gottingen airfoil blade. The experimental studies on the basic rule and the regulatory mechanisms of prewhirl regulation for the centrifugal pump were made. Comparison experiment tests showed that the inlet guide vane installed with long-string side close to the center axis on the improvement of the external characteristics of centrifugal pump was better than the other. Also the inlet guide vane installed with long-string side close to the center axis has enlarged the high efficiency scope and improved the hydraulic performance of the centrifugal pump. When compared with the performance of the centrifugal pump without inlet guide vane, the peak value of efficiency was enhanced by 2.3% after the guide vane was installed. This method improved efficiency and saved energy for the centrifugal pump. Number of references:10 Main heading:Centrifugal pumps Controlled terms:Airfoils - Experiments - Wakes Uncontrolled terms:Airfoil blades - Axial flow pump - Blade design - Experiment tests - Experimental studies - External characteristic - Guide vane - Hydraulic performance - Inlet guide vane - Peak values - Prewhirl regulation - Regulatory mechanism Classification code:618.2 Pumps - 631.1 Fluid Flow, General - 652.1 Aircraft, General - 901.3 Engineering Research DOI:10.6041/j.issn.1000-1298.2012.11.024 Database:Compendex 10. Accession number:20125115822679 Title:High-accuracy soil temperatures in situ measurement system Authors:Wang, Fushun1, 2 ; Liu, Yongfu1 ; Sun, Xiaohua3 ; Cai, Zhenjiang2 ; Wang, Shutao1 Author affiliation:1 College of Information Science and Technology, Hebei Agricultural University, Baoding 071000, China 2 College of Mechanical and Electrical Engineering, Agricultural University of Hebei, Baoding 071000, China 3 Department of Digital Transmit, Hebei Software Institute, Baoding 071000, China Corresponding author:Cai, Z. (caj65@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:102-106 57 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:High-accuracy measuring system of soil temperatures was designed. Thermocouple was used as temperature sensors. Under the control of the micro-controller, high-accuracy and automatic detection was achieved to analyze the impact of soil temperature on water and heat of soil. The system was studied from three aspects, such as hardware circuit, software and curve fitting. By using the electric bridge method for temperature acquisition, least squares method was used to piecewise fit samples values and temperature. Their relationship curve was described. The measurement error was compensated and corrected to ensure the measurement precision. The result showed that the experimental absolute error was less than 0.02°C. Number of references:11 Main heading:Least squares approximations Controlled terms:Bridge circuits - Curve fitting - Measurements - Temperature - Thermocouples Uncontrolled terms:High-accuracy - Least squares methods - Measurement system - Piece-wise - Soil temperature Classification code:944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 944.5 Temperature Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 703.1 Electric Networks - 641.1 Thermodynamics - 921.6 Numerical Methods DOI:10.6041/j.issn.1000-1298.2012.11.019 Database:Compendex 11. Accession number:20125115822680 Title:Calculating and experiment on drainage pressure difference of self-cleaning screen filter for drip irrigation Authors:Zong, Quanli1, 2 ; Liu, Fei2 ; Liu, Huanfang1 ; Zheng, Tiegang3 Author affiliation:1 College of Water Conservancy and Architectural Engineering, Shihezi University, Shihezi 832000, China 2 State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China 3 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China Corresponding author:Zong, Q. (quanli1871@126.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:107-112 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The drainage pressure difference of self-cleaning screen filter was calculated, and the total value of pressure difference for 80 mesh and 120 mesh was also calculated respectively at first. Contrasting with measured value, the result indicated that the calculated value and measured value were substantial identical. Then, the law of pressure difference was analyzed particularly, which influenced by restriction condition as flow, sand and time, etc. Finally, the variation curve of clean and muddy head loss acquired by the experiments, under the condition that the head loss could not ascend sharply, the best drainage pressure difference for two kinds of mesh was put forward, which could provide reference for the pressure difference calculation of screen filter. Number of references:15 Main heading:Cleaning Controlled terms:Experiments - Irrigation Uncontrolled terms:Calculated values - Drip irrigation - Head loss - Pressure differences - Restriction condition - Screen filters - Self-cleaning - Total values Classification code:802.3 Chemical Operations - 821.3 Agricultural Methods - 901.3 Engineering Research DOI:10.6041/j.issn.1000-1298.2012.11.020 Database:Compendex 12. Accession number:20125115822663 Title:Energy conversion and transfer process of free-piston engine generator Authors:Tian, Chunlai1 ; Feng, Huihua1 ; Shang, Jiao1 ; Zuo, Zhengxing1 Author affiliation:1 School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China Corresponding author:Feng, H. (fenghh@bit.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:11-14 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Based on the law of conservation of energy, the energy model in each cycle of the free-piston generator was established. The energy conversion in one cycle was obtained and the transfer process in continuous cycles was analyzed. The rules of influence of different compress ratios on energy and performance were attained. The results showed that the brake efficiency of the free-piston generator could be 40% ideally. The loss in the combustion, scavenging and heat release was the big part of the whole. In the continuously running, much energy at the end of the power stroke in one cylinder was transferred into the other cylinder as the compress energy. It affected the next combustion. The effects with the compress ratio varying on energy conversion and brake efficiency were different. Keeping the compress energy stable was important for the operation control. Number of references:10 Main heading:Engine pistons Controlled terms:Brakes - Combustion - Energy conversion - Energy transfer Uncontrolled terms:Energy conversation - Energy model - Energy transfer process - Engine generator - Free piston - Free-piston generator - Heat release - Law of conservation of energy - Operation control - Power strokes - Transfer process Classification code:521.1 Fuel Combustion - 525.4 Energy Losses (industrial and residential) - 525.5 Energy Conversion Issues - 602 Mechanical Drives and Transmissions - 612.1.1 Internal Combustion Engine Components DOI:10.6041/j.issn.1000-1298.2012.11.003 Database:Compendex 13. Accession number:20125115822667 Title:Effect of engine operating parameters on calculation results of different heat release models for CNG engine Authors:Zhang, Hongguang1 ; Han, Xuejiao1 ; Yao, Baofeng1 Author affiliation:1 College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China Corresponding author:Zhang, H. (zhg5912@263.net) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:31-35 40 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to study the effect of operating parameters on the heat release models calculation result of compressed natural gas (CNG) engine and confirm the models application conditions, Gatowski et al model, Apparent heat release model and R-W model were used to calculate heat release rate and mass fraction burned based on the cylinder pressure and crank angle data measured from a spark ignition CNG engine. The effect of engine operating parameters on the calculate results of different heat release models were discussed. The results show that the difference of heat release rate and mass fraction burned calculated between Apparent heat release model and R-W model is not obvious, which indicates that the two models can be in common use. The three models are affected slightly by ignition advance angle and excess air ratio. Difference among three models calculation results is not huge with small throttle opening. Compared with the other two models, the calculation results of Gatowski et al model are affected significantly by engine speed. The three models substitutes mutually under the condition of small throttle opening or high engine speed. Gatowski et al model is more accurate and suitable for slow engine speed compared with the other two models. Number of references:11 Main heading:Engine cylinders Controlled terms:Engines Uncontrolled terms:CNG engine - Heat release - Heat Release Rate (HRR) - Mass fraction - Operating parameters Classification code:612 Engines - 612.1.1 Internal Combustion Engine Components DOI:10.6041/j.issn.1000-1298.2012.11.007 Database:Compendex 14. Accession number:20125115822690 Title:Joint optimization recall model of small scale agricultural products processing enterprise Authors:Li, Feng1 ; Wu, Huarui1 ; Zhu, Huaji1 ; Miao, Yisheng1 ; Ma, Weihong1 Author affiliation:1 National Engineering Research Center for Information Technology in Agriculture, Beijing 100097, China Corresponding author:Wu, H. (wuhr@nercita.org.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:157-162 168 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Refer to the shortage of current recall model which can only optimize recalled size, the batch dispersion model was analyzed. The quality property was added to the bath dispersion model. The constraint condition based on the size proportion and quality weight of raw material-component-finished product was given. The joint optimization model of recalled size and product quality was proposed. The computing consumption was discussed. Results of algorithm analysis and optimization examples showed that the model could reduce the recalled size on the basis of improved quality of the finished product. Number of references:22 Main heading:Optimization Controlled terms:Agricultural products - Dispersions Uncontrolled terms:Algorithm analysis - Batch dispersion - Constraint conditions - Dispersion models - Finished products - Joint optimization - Product quality - Products recall - Quality properties - Small scale - Traceability Classification code:821.4 Agricultural Products - 921.5 Optimization Techniques - 951 Materials Science DOI:10.6041/j.issn.1000-1298.2012.11.030 Database:Compendex 15. Accession number:20125115822661 Title:Effects of intake swirl and spray angle on combustion performance for diesel engine Authors:Yuan, Ye1 ; Li, Guoxiu1 ; Li, Hongmeng1 Author affiliation:1 School of Mechanical, Electronic and Control Engineering, Beijing Jiaotong University, Beijing 100044, China Corresponding author:Li, G. (gxli@bjtu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:1-6 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Multi-dimensional simulation was conducted on a small high intensified diesel engine. The influence mechanism of the interaction of intake swirl and spray angle on the in-cylinder mixture distribution, fuel evaporation, mixing and heat release processes was analyzed. Optimum matching criteria was finally acquired. The results showed that increasing and decreasing the intake swirl and spray angle could accelerate the fuel evaporation rate before and after TDC respectively. Swirl could accelerate the process of mixing fuel and air, but if spray angle was too large, the mixing rate in the later part of injection could be retarded. When the swirl ratio and spray angle were matched appropriately, the mixture would be more uniform and the SMD would be smaller, which could significantly optimize the premixed combustion process. Number of references:11 Main heading:Diesel engines Controlled terms:Combustion - Evaporation - Fuels - Intake systems - Mixing - Phase transitions Uncontrolled terms:Combustion performance - Fuel evaporation - Fuel injection systems - Heat release - Influence mechanism - Intake swirl - Interaction - Mixing rates - Mixture distributions - Multidimensional simulation - Optimum matching - Premixed combustion - Spray angle - Swirl ratio Classification code:801.4 Physical Chemistry - 631.1 Fluid Flow, General - 612.2 Diesel Engines - 802.3 Chemical Operations - 524 Solid Fuels - 522 Gas Fuels - 521.1 Fuel Combustion - 523 Liquid Fuels DOI:10.6041/j.issn.1000-1298.2012.11.001 Database:Compendex 16. Accession number:20125115822698 Title:Quantity qualification of overlapped region for citrus image based on modified Freeman chain code algorithm Authors:Gong, Aiping1 ; Chen, Ji1 ; Qiu, Zhengjun1 ; He, Yong1 Author affiliation:1 College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China Corresponding author:Qiu, Z. (zjqiu@zju.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:203-208 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:A modified Freeman chain code algorithm to determine the number of overlapped regions in citrus binary images was proposed. Three components, including S, 8, and 9, were inserted in the original Freeman code. During the identification process, the improved chain code was first obtained. Then the appeared times of code "8 " was computed. The number of fruits in the overlapped regions can be obtained according to the outline of the fruits. The improved chain code algorithm was applied to evaluate the citrus images. The experimental results showed that the proposed algorithm was effective in identifying the overlapped fruits when the number of overlapped regions was between 2and 3where it achieved accuracy of 100%. Number of references:26 Main heading:Algorithms Controlled terms:Fruits - Image recognition Uncontrolled terms:Chain codes - Citrus - Freeman chain code - Freeman code - Identification process - Image-based - Overlap - Overlapped region - Three component Classification code:716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 821.4 Agricultural Products - 921 Mathematics DOI:10.6041/j.issn.1000-1298.2012.11.038 Database:Compendex 17. Accession number:20125115822671 Title:Spatial variability of maize yield and relations to terrain attributes in salinized plain region Authors:Zhang, Xiaoguang1 ; Huang, Biao1 ; Zhang, Beier1 ; Zhao, Yongcun1 ; Sun, Weixia1 ; Hu, Wenyou1 Author affiliation:1 Key Laboratory of Soil Environment and Pollution Remediation, Chinese Academy of Sciences, Nanjing 210008, China Corresponding author:Huang, B. (bhuang@issas.ac.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:51-57 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Using Yucheng county with soil salinization as a typical area of the north China plain, spatial variability of maize yields was described and influence of the terrain attributes on maize yields were discussed by space interpolation techniques based on measuring maize yields in field and extracting terrain information. The results showed that maize yields gradually increased along the northeast to southwest of the county with increasing the elevation. Although terrain undulated very slightly, the increasing trend of the elevation was agreement with the distribution of yields from low to high. A very significantly positive correlation (R=0.263, p<0.01) existed between maize yields and elevation. Meanwhile, a significantly negative correlation (R=-0.245, p<0.05) existed between maize yields and plane curvature, indicating that the bigger plane curvature, the easier saline accumulation leading to decreased maize yields. The combined effects of elevation and plane curvature explained 12.4% of the observed variability of maize yields. Number of references:23 Main heading:Geomorphology Controlled terms:Landforms Uncontrolled terms:Combined effect - In-field - Interpolation techniques - Low-to-high - Maize yield - Negative correlation - North China Plain - Positive correlations - Salinized land - Soil salinization - Spatial variability - Terrain - Terrain attributes Classification code:481.1 Geology - 481.1.1 Geomorphology DOI:10.6041/j.issn.1000-1298.2012.11.011 Database:Compendex 18. Accession number:20125115822681 Title:Simulation of tracer particles movement by discrete phase model in the centrifugal pump Authors:Li, Yalin1 ; Yuan, Shouqi1 ; Tang, Yue1 ; Huang, Ping1 ; Li, Xiaojun1 Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China Corresponding author:Yuan, S. (shouqiy@ujs.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:113-118 64 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Motion of tracer particles in the centrifugal pump was calculated by discrete phase model. In this model, the fluid field of the centrifugal pump was solved by the two-equation RNG k-Ε turbulence model. The pump performance curves were simulated to check the calculation accuracy by comparing with the experimental performance curves. Based on the result of the flow field, the tracks of tracer particles with different densities and diameters in various conditions were achieved by using Lagrange method. Through comparing particle trajectory with fluid streamline and analyzing the particle speed changed in the relationship with the spatial scale, the particles tracking characteristics were studied. Numerical simulation results showed that tracking characteristics of different densities, particles were significantly different when their diameters were greater than 50 μm. While diameters were less than 20 μm, densities were very low impact on the following performance. It was very important when the particle density was equal to the density of fluid. In the channel with unstable flow such as the vortex flow, the particle trajectory line was closed to the fluid flow line when the tracer particle with smaller diameters and the density was the same with the fluid density. Changing with spatial scale, the particle's speed was closed to the fluid velocity when the particle's diameter was under 20 μm. Finally, taking the particle scattering characteristics into account, it was recommended that 20 μm polystyrene should be chosen as tracer particles for this centrifugal pump. Number of references:11 Main heading:Computer simulation Controlled terms:Centrifugal pumps - Polystyrenes - Turbulence models Uncontrolled terms:Calculation accuracy - Density of fluid - Discrete phase model - Fluid densities - Fluid field - Fluid velocities - Lagrange methods - Particle densities - Particle scattering - Particle trajectories - Performance curve - Pump performance - Spatial scale - Tracer particle - Two-equation - Unstable flows Classification code:443.1 Atmospheric Properties - 618.2 Pumps - 723.5 Computer Applications - 815.1.1 Organic Polymers DOI:10.6041/j.issn.1000-1298.2012.11.021 Database:Compendex 19. Accession number:20125115822688 Title:Effects of supplement dose of microorganism in biological pretreatment of wheat straw on its characteristics of anaerobic digestion for biogas production Authors:Liu, Ronghou1 ; Wu, Jinkai1 ; Wu, Lijuan1 Author affiliation:1 School of Agriculture and Biology, Shanghai Jiao Tong University, Shanghai 200240, China Corresponding author:Liu, R. (liurhou@sjtu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:147-151 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Co-pretreatment of wheat straw by urea and microorganism was conducted. The effects of supplement dose of microorganism in biological pretreatment of wheat straw on its anaerobic digestion for biogas production were investigated by using a self-made anaerobic digestion device with pretreated wheat straw as raw materials. Results showed that the total yield of biogas reached the maximum of 7 968 mL, which was 23.11% higher than the control, when the urea concentration, pH value of biological pretreatment and ratio of Phanerochaete chrysosporium to Trichoderma reesei added into the wheat straw were 35 g/L, 4, and 1:1, respectively. The values of VFA, CH4 and pH value were located in normal range. The maximum CH4 content was 51.33%, which was 6.01% higher than that of control. The fermentation time was shortened to 23d during the whole experiment. Number of references:16 Main heading:Anaerobic digestion Controlled terms:Biogas - Metabolism - pH - Urea Uncontrolled terms:Biogas production - Biological pre-treatment - pH value - Phanerochaete chrysosporium - Total yield - Trichoderma reesei - Wheat straws Classification code:452.4 Industrial Wastes Treatment and Disposal - 522 Gas Fuels - 801.1 Chemistry, General - 801.2 Biochemistry - 804.1 Organic Compounds DOI:10.6041/j.issn.1000-1298.2012.11.028 Database:Compendex 20. Accession number:20125115822670 Title:Soil pedotransfer function of multiple data source and its uncertainty in water simulation Authors:Wang, Gaigai1 ; Zhang, Yulong1 ; Yu, Na1 Author affiliation:1 College of Land and Environment, Shenyang Agricultural University, Shenyang 110866, China Corresponding author:Zhang, Y. (ylzsau@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:45-50 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Pedotransfer function was established to predict soil water retention curve by using the feed-forward neural networks methods. The prediction performance and application uncertainty of pedotransfer function were analyzed according to the error statistics index and Hydrus-1D water dynamics model. The results showed that mean absolute error value of θ1000, θ10000, θ15000 (soil water retention θ1000, θ10000, θ15000 at soil water suction equal to 1000 cm, 10 000 cm and 15 000 cm, respectively) using pedotransfer functions with particle size distribution, bulk density, θ60 as predictor was 42.86%, 23.87% and 26.15% lower than the value of PTF1using particle size distribution as predictor. Mean absolute error of θ100, θ10000, θ15000 using pedotransfer function which added θ15000 as predictor was 8.67%, 16.96% and 15.95% lower than pedotransfer function using θ60(soil water θ60 at soil water suction equal to 60 cm) as predictor. The parameters of van Genuchten equation were predicted using pedotransfer function were used to simulate soil water, the MAE value of PTF using θ60 as predictor was 11.11% lower than PTF using particle size distribution as predictor. Therefore, adding additional θ15000 cannot reduce the uncertainty of pedotransfer function application comparing with the pedotransfer function using particle size, bulk density θ60 as predictor. Number of references:19 Main heading:Hydraulic conductivity Controlled terms:Error statistics - Particle size analysis - Soil moisture - Uncertainty analysis Uncontrolled terms:Bulk density - Data resources - HYDRUS-1D - Mean absolute error - Multiple data sources - Pedotransfer functions - Prediction performance - Soil water - Soil water retention - Soil water retention curves - Uncertainty - Water dynamics - Water simulations Classification code:483.1 Soils and Soil Mechanics - 632.1 Hydraulics - 922.1 Probability Theory - 922.2 Mathematical Statistics - 951 Materials Science DOI:10.6041/j.issn.1000-1298.2012.11.010 Database:Compendex 21. Accession number:20125115822708 Title:Model of grinding force based on stress concentration theory Authors:Lin, Kairong1, 2 ; Xu, Xipeng1 ; Li, Yuan1 ; Fang, Congfu1 Author affiliation:1 Engineering Research Center for Machining of Brittle Materials, Ministry of Education, Huaqiao University, Xiamen 361021, China 2 College of Mechanical Engineering, Jimei University, Xiamen 361021, China Corresponding author:Xu, X. (xpxu@hqu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:261-266 243 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Stress concentration theory was introduced into study of grinding, and the stress concentration phenomenon in grinding process was analyzed. A single-grit model of grinding force was established based on stress concentration theory. The influence mechanism of grit-wear-area rate on cutting force was clarified with the model. Functions between grinding force and grit-wear-area rate was established. The functions showed the quadratic function relationship between grinding force and grit-wear-area rate, and the increase of the cumulative residual-grinding-thickness results in the rapid increase of normal grinding force. Furthermore, by taking the feature of the grinding wheel in use into consideration, functions of grinding force for multi-grit grinding wheel was established. The validity of the model was verified by the experimental data. Number of references:16 Main heading:Grinding (machining) Controlled terms:Grinding wheels - Stress concentration Uncontrolled terms:Concentration phenomena - Cutting forces - Grinding force - Grinding process - Grit - Influence mechanism - Quadratic function - Wear-area rate Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 606.2 Abrasive Devices and Processes DOI:10.6041/j.issn.1000-1298.2012.11.048 Database:Compendex 22. Accession number:20125115822693 Title:Physical and chemical characteristics and composition analysis for white sesame oil Authors:Liang, Shaohua1 ; Peng, Le1 ; Wang, Yadong1 ; Wang, Peihui1 Author affiliation:1 College of Food Science and Technology, Henan University of Technology, Zhengzhou 450052, China Corresponding author:Liang, S. (shaohualiang832@126.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:174-179 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The physical and chemical indexes of the squeezing white sesame oil from different areas were determined, including the refraction index, saponification number and unsaponifiable matter content, etc. The fatty acid compositions of white sesame oil were analyzed by using gas chromatography. The relatively content of unsaturated fatty acids was more than 84%. The method of pancreatic enzyme selective hydrolysis was used to analyze the triacylglycerols molecular structures in the squeezing white sesame oils. The LOL (sn-2-oleic acid-1, 3-two linoleic acid glyceride) relatively content was the highest (22.98%~25.62%). The vitamin E and sesamin contents of the sesame oil were 13.73~54.43mg/(100 g) and 60.14~69.10 mg/(100 g) respectively which were analyzed by using HPLC. The oxidative stability of the squeezing white sesame oil of different areas were measured. The results showed that the oxidative stability of white sesame oil (No.4) was relatively good. Number of references:22 Main heading:Vegetable oils Controlled terms:Gas chromatography - Glycerol - Hydrolysis - Linoleic acid - Oleic acid - Oxidation resistance - Unsaturated fatty acids Uncontrolled terms:Composition analysis - Fatty acid composition - Oxidative stability - Physical and chemical characteristics - Refraction index - Saponification numbers - Sesame oil - Sesamin - Triacylglycerols - Vitamin-E Classification code:801 Chemistry - 802.2 Chemical Reactions - 804.1 Organic Compounds DOI:10.6041/j.issn.1000-1298.2012.11.033 Database:Compendex 23. Accession number:20125115822686 Title:Research on the performance improvement of axial-flow pump under unstable condition using CFD Authors:Yang, Hua1 ; Sun, Dandan2 ; Tang, Fangping1 ; Liu, Chao3 Author affiliation:1 School of Energy and Power Engineering, Yangzhou University, Yangzhou 225009, China 2 Institute of Water Conservancy Works Design of Xuzhou, Xuzhou 221002, China 3 School of Water Conservancy Science and Engineering, Yangzhou University, Yangzhou 225009, China Corresponding author:Yang, H. (yanghua@yzu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:138-141 151 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The recirculation flow exists at the inlet of the impeller when the axial-flow pumps operate at the low flow rate. At this condition, the pump efficiency falls down and the pump system vibrates seriously, sometimes leads to structural damage, so the pump should avoid operating at this unstable condition. Five schemes with different baffles at the inlet of axial-flow pump impeller were presented. 3-D incompressible flow fields, for different baffle schemes, were simulated by using the commercial software ANSYS CFX. The computed results showed that the distance between the baffles and the impeller was the key factor that influences the performance of axial-flow pumps at the condition of low flow rate. Among these five schemes, scheme No.3was the preferred plan. The flow field at the meridional plane shows that baffles could reduce the backflow at the inlet of axial-flow pump, reduce the pressure at the suction side and increase the lift of the blade, so as to increase the efficiency of axial-flow pumps at the condition of low flow rate. Number of references:12 Main heading:Pumps Controlled terms:Computer simulation - Flow fields - Flow rate - Impellers - Inlet flow Uncontrolled terms:Axial flow pump - Backflow - Commercial software - Key factors - Meridional planes - Performance - Performance improvements - Pump efficiency - Pump system - Re-circulation flow - Structural damages - Suction side - Unstable condition Classification code:601.2 Machine Components - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 723.5 Computer Applications DOI:10.6041/j.issn.1000-1298.2012.11.026 Database:Compendex 24. Accession number:20125115822689 Title:Effect of pretreatment methods on anaerobic fermentation characteristics from rice straw Authors:Luo, Lina1 ; Li, Wenzhe1 ; Xu, Minghan1 ; Li, Chengyi2 ; Dou, Yucheng3 Author affiliation:1 College of Engineering, Northeast Agricultural University, Harbin 150030, China 2 Heilongjiang Nongken Great Northern Wilderness Cattle Industry, Shuangyashan 155100, China 3 Heilongjiang Institute of Agricultural Mechanical Engineering Science, Harbin 150030, China Corresponding author:Li, W. (liwenzhe9@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:152-156 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Under mesophilic temperature (35°C), the component changes of rice straw before and after anaerobic fermentation were compared. Results show that gas production of amination pretreatment straw is the largest, and VS gas production is 356.80 mL/g, 11.70% higher than the control group; the maximum of methane is achieved 70% above, which shows no significant difference between each group. Lignocellulose content presented down trend after anaerobic fermentation, and degradation rate is proportional to the gas production. Compared with the original rice straw, cellulose, hemicellulose and lignin degradation rates of amination pretreatment straw are 28.49%, 51.73% and 7.13% respectively. Number of references:15 Main heading:Cellulose Controlled terms:Amines - Anaerobic digestion - Degradation - Lignin - Methane Uncontrolled terms:Anaerobic fermentation - Control groups - Degradation rate - Gas productions - Lignin degradation - Mesophilic temperature - Pre-Treatment - Pretreatment methods - Rice straws Classification code:802.2 Chemical Reactions - 804.1 Organic Compounds - 815.1.1 Organic Polymers DOI:10.6041/j.issn.1000-1298.2012.11.029 Database:Compendex 25. Accession number:20125115822694 Title:Effects of air velocity in heat exchanging pipes to heat exchanging and water vapor transformation of underground heat storage system in greenhouse during heating Authors:Wang, Yongwei1 ; Liang, Xifeng2 ; Cheng, Shaoming1 ; Wang, Jun1 ; Miao, Xiangwen1 Author affiliation:1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310029, China 2 College of Mechanical and Electrical Engineering, China Jiliang University, Hangzhou 310018, China Corresponding author:Wang, Y. (wywzju@zju.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:180-185 219 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Effects of the air velocity in heat exchanging pipes on heat exchanging and water vapor transformation was studied in double-film covering greenhouse during heating at night in winter. The temperature and humidity in inlet and outlet of heat exchanging pipes, floor temperature in heat storage greenhouse and outside temperature were measured at different air velocities in the heat exchanging pipes. The humidity ratio, enthalpy of inlet and outlet of heat exchanging pipes and the power for heating were computed. The results showed that the temperature and enthalpy of cold air with high humidity flowing through heat exchanging pipes increased apparently and the humidity reduced when the air velocities in heat exchanging pipes were respectively 0.6 m/s, 1.0 m/s, 1.5 m/s, 2.0 m/s, 2.5 m/s and 2.8 m/s during heating at night after heat saving in clear days. The power for heating was enhanced with the increase of the air velocity in heat exchanging pipes. The average power for heating is 1.0 kW, 1.6 kW, 3.2kW, 6.4 kW, 7.2kW and 7.7 kW respectively. The heating effects is not distinct when the air velocity in heat exchanging pipes is less than 2 m/s, while the continuity for heating is poor when the air velocity in heat exchanging pipes is higher than 2.5 m/s. Therefore the rational air velocity in heat exchanging pipes is 2.0 m/s for heating at night when the temperature satisfies the growing requirements of the crops. Number of references:23 Main heading:Air Controlled terms:Enthalpy - Greenhouses - Heat exchangers - Heat storage - Heating - Vapors - Velocity Uncontrolled terms:Air velocities - Average power - Cold air - Heat exchanging - Heat saving - Heating effect - High humidity - Humidity ratio - Underground heat storage Classification code:931.1 Mechanics - 804 Chemical Products Generally - 643.1 Space Heating - 641.2 Heat Transfer - 641.1 Thermodynamics - 616.1 Heat Exchange Equipment and Components - 402.1 Industrial and Agricultural Buildings DOI:10.6041/j.issn.1000-1298.2012.11.034 Database:Compendex 26. Accession number:20125115822706 Title:Molecular dynamics simulation of nanoscale contact process Authors:Yang, Xiaojing1 ; Zhan, Shengpeng1 ; Chi, Yilin2 Author affiliation:1 Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming 650500, China 2 Faculty of Mechanical and Electrical Engineering, Kunming University of Science and Technology, Kunming 650500, China Corresponding author:Yang, X. (xjyang@vip.sina.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:250-255 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to study nanoscale contact mechanics behavior, taking the rigid hemispherical surface contacted on and pressed in the silicon surface as the research object, the molecular dynamics model of nanoscale contact process was established. State changing of microscopic contact area and variation law of contact force was acquired. Results showed that the adhesion force caused the hemispherical surface and monocrystalline silicon surface to jump-to-contact when the hemispherical surface has not fully contact with monocrystalline silicon substrate surface. With the increase of contact depth, dislocations and sliding of matrix atoms appeared successively. The initial stage of contact was mainly elastic deformation with some dislocations. The later stage of contact was plastic deformation with lots of dislocation accumulation. In the process of disengagement, the substrate material generated some extent elastic recovery. When the hemispherical surface and the matrix surface were completely out of touch, the contact surface still contacted with some matrix atoms due to adhesion phenomenon. Finally, atomic force microscopy was used to finish comparative analysis of the experiment according to the parameter conditions and the contact process of molecular dynamics. The experimental results showed that molecular dynamics simulation was practicable and effective for analysis of the nanoscale contact mechanics behavior. Moreover, molecular dynamics simulation could acquire the microscopic details that not be observed through the experiment. Number of references:13 Main heading:Surfaces Controlled terms:Adhesion - Atomic force microscopy - Contacts (fluid mechanics) - Deformation - Experiments - Molecular dynamics - Molecular mechanics - Monocrystalline silicon - Nanotechnology Uncontrolled terms:Adhesion forces - Adhesion phenomena - Comparative analysis - Contact areas - Contact depth - Contact forces - Contact Mechanics - Contact process - Contact surface - Dislocation accumulation - Elastic recovery - Hemispherical surfaces - Initial stages - Jump-to-contact - Matrix atoms - Molecular dynamics simulations - Molecular-dynamics model - Nano scale - Parameter conditions - Research object - Silicon surfaces - Substrate material Classification code:931.1 Mechanics - 901.3 Engineering Research - 801.4 Physical Chemistry - 801 Chemistry - 951 Materials Science - 761 Nanotechnology - 712.1.1 Single Element Semiconducting Materials - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties - 741.3 Optical Devices and Systems DOI:10.6041/j.issn.1000-1298.2012.11.046 Database:Compendex 27. Accession number:20125115822669 Title:Experiment on electric temporary turbocharger for small diesel engines Authors:Zhang, Junchang1 ; Shi, Shuaibing1 ; Guo, Kangquan1 ; Dang, Gerong1 ; Jing, Yujiang1 ; Zhang, Yang1 Author affiliation:1 College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China Corresponding author:Shi, S. (ngxssb@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:41-44 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Small diesel engines have weak dynamic performance and emit black smoke when working overload in a short time. With the aim to solve that problem, a kind of electric temporary turbocharger was designed. The system includes a supercharger driven by DC brushless motor, power supply system on board and a switch. The system is powered by a 24 V battery and does not consume too much power due to its short running time. Bench test showed that the supercharging ratio of the electric temporary turbocharger was between 1.014 and 1.020. The power of diesel engine increased by 5.0%~9.1%. The fuel consumption decreased by 8.5%~14.0%. The smoke exhaust problem was improved. Test results indicated that the electric temporary turbocharger could meet requirement when the small diesel engines were weak dynamic performance temporarily. Number of references:10 Main heading:Diesel engines Controlled terms:Brushless DC motors - Design - Electric power systems - Experiments - Superchargers - Turbomachinery Uncontrolled terms:Bench tests - Black smoke - Dc brushless motors - Dynamic performance - Performance experiment - Running time - Small diesel engine - Temporary super charge Classification code:706.1 Electric Power Systems - 705.3.2 DC Motors - 618.1 Compressors - 901.3 Engineering Research - 618 Compressors and Pumps - 612.1.1 Internal Combustion Engine Components - 408 Structural Design - 612.2 Diesel Engines DOI:10.6041/j.issn.1000-1298.2012.11.009 Database:Compendex 28. Accession number:20125115822691 Title:Non-destructive detection of Agaricus bisporus firmness based on near-infrared diffused spectroscopy Authors:Wang, Juan1 ; Zhang, Rongfang1 ; Wang, Xiangyou1 Author affiliation:1 School of Agricultural and Food Engineering, Shandong University of Technology, Zibo 255049, China Corresponding author:Wang, X. (wxy@sdut.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:163-168 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Calibration model for firmness of Agaricus bisporus during storage was developed based on near-infrared (NIR) diffuse reflectance spectroscopy quantitative analysis techniques. Partial least squares (PLS) regression was carried out to analyze the spectroscopy. Four different spectral pretreatment methods (first derivative, second derivative, SNV, SMC) were used to compare calibration results for firmness. The result showed that the best calibration models, in the selected wavelength range of 5000~10000 cm-1, could be obtained by the second derivative spectrum with the determination coefficient of calibration of 0.9471, and the determination coefficient of prediction of 0.8261. The results indicated that the detection method based on near-infrared diffuse reflectance spectroscopy was simple, and could be used for non-destructively evaluating the changes of firmness in Agaricus bisporus during storage in time. Number of references:22 Main heading:Infrared devices Controlled terms:Calibration - Spectroscopy Uncontrolled terms:Agaricus bisporus - Calibration model - Detection methods - Determination coefficients - Diffuse reflectance spectroscopy - Firmness - First derivative - Near Infrared - Nondestructive detection - Partial least-squares regression - Pretreatment methods - Second derivative spectra - Second derivatives - Wavelength ranges Classification code:741.3 Optical Devices and Systems - 801 Chemistry - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments DOI:10.6041/j.issn.1000-1298.2012.11.031 Database:Compendex 29. Accession number:20125115822692 Title:Process optimization of dimethoate pesticide degradation by ultrasound in aqueous solution Authors:Ma, Haile1 ; Sun, Baosheng1 ; He, Ronghai1 ; Luo, Lin1 ; Wang, Zhenbin1 Author affiliation:1 School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China Corresponding author:Ma, H. (mhl@ujs.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:169-173 179 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Using flat sweeping frequency ultrasonic technology, degradation of dimethoate in aqueous solution under ultrasonic field at different ultrasonic frequencies, fixed/sweeping modes, radiate solution volumes, radiate time were investigated. Radical mechanism under ultrasonic field was studied. The results showed that degradation efficiency at sweeping frequency ultrasound mode was proved to be superior to that at fixed mode, and the efficiency of double ultrasonic plats was better than the simple plat. The better treatment system of ultrasonic degradation operating parameters were frequency 68 kHz, power 80 W (corresponding to the processing volume of 8 L), sweeping period 100 ms, frequency combination of 68 kHz with 68 kHz, radiate time 180 min. Under these conditions, the degradation rate of dimethoate with initial concentration 3mg/L reached 71%. Mechanism study results indicated that the degradation of dimethoate in aqueous solution by ultrasonic was partly caused by free radical oxidation. Number of references:14 Main heading:Solutions Controlled terms:Degradation - Free radicals - Optimization - Pesticides - Process control - Ultrasonics Uncontrolled terms:Degradation efficiency - Degradation rate - Dimethoate - Fixed modes - Free radical oxidation - Fruit and vegetables - Initial concentration - Operating parameters - Pesticide degradation - Radical mechanism - Solution volume - Sweeping frequencies - Sweeping period - Treatment systems - Ultrasonic degradation - Ultrasonic field - Ultrasonic frequency - Ultrasonic technology Classification code:731 Automatic Control Principles and Applications - 753.1 Ultrasonic Waves - 802.2 Chemical Reactions - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 921.5 Optimization Techniques DOI:10.6041/j.issn.1000-1298.2012.11.032 Database:Compendex 30. Accession number:20125115822664 Title:Influence of nozzle hole cone angle on swirl chamber combustion system in direct injection diesel Authors:Wei, Shengli1 ; Wang, Zhong1 ; Mao, Gongping1 ; Ni, Peiyong1 Author affiliation:1 School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China Corresponding author:Wei, S. (weishengli@ujs.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:15-20 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to improve the particle spatial distribution, promote the mixing of oil and gas, and enhance airflow movement in a combustion chamber, a swirl chamber combustion system in direct injection diesel was investigated. The mixture formation and combustion progress in the combustion chamber were simulated, including different nozzle hole cone angles with 146°, 150° and 154°. The results showed that in view of the fuel/air equivalence ratio distribution, the uniformity of mixture on nozzle hole cone angle of 146°was better than others. The combustion swirl and anti-squish swirl have effect on temperature distribution in the combustion chamber. NO emission was lowest with nozzle hole cone angle of 154°, while soot emission was lowest with nozzle hole cone angle of 146°. The emission performance was better than others with nozzle hole cone angle of 150°. Number of references:10 Main heading:Nozzles Controlled terms:Combustion chambers - Computer simulation - Fuel systems Uncontrolled terms:Combustion systems - Cone angle - Direct injection diesel - Emission performance - Equivalence ratios - Mixture formation - NO emissions - Nozzle holes - Oil and gas - Particle spatial distribution - Soot emissions - Swirl chambers Classification code:522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 631.1 Fluid Flow, General - 654.2 Rocket Engines - 723.5 Computer Applications DOI:10.6041/j.issn.1000-1298.2012.11.004 Database:Compendex 31. Accession number:20125115822675 Title:Photosynthesis rate and leaf water use efficiency of Korla fragrant pear tree under regulated deficit irrigation Authors:Wu, Yang1 ; Wang, Wei2 ; Zhao, Zhi1 ; Huang, Xingfa1 ; Fan, Yuntao3 ; Su, Liuyun4 Author affiliation:1 College of Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, China 2 College of Engineering, China Agricultural University, Beijing 100083, China 3 Chinese Academy of Agricultural Mechanization Sciences, Beijing 100083, China 4 Forestry Technology Promotion Center of Bayingolin Mongol Autonomous Prefecture, Korla 841000, China Corresponding author:Wang, W. (weiwang@cau.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:80-86 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The experiment was conducted to study the effects of regulated deficit irrigation on these parameters of the Korla fragrant pear tree.The water deficit applied before the fruit enlargement stage included: slight water deficit, the trees were irrigated with 60% of US Class A pan evaporation (Ep); severe water deficit, the trees were irrigated with 40% of Ep. During the fruit enlargement stage, both water deficit treatments were irrigated with 80% of Ep. The control was irrigated with 80% of Ep during the whole growth season. The results indicated that the leaf photosynthesis rate, transpiration rate and stomatal conductance were significantly reduced by the soil water deficit. After full irrigation resumed, the leaf photosynthesis rate, transpiration rate and stomatal conductance restored rapidly to some extent, the physiological parameters of slight water deficit reached the control level in the middle August, however, those of the severe water deficit were always lower than the control. As compared with the photosynthesis, the transpiration was more sensitive to the soil water deficit, resulting in the improvement of the leaf water use efficiency. Number of references:27 Main heading:Plants (botany) Controlled terms:Efficiency - Forestry - Fruits - Photosynthesis - Physiological models - Transpiration - Water supply Uncontrolled terms:Korla fragrant pear - Photosynthesis rate - Regulated deficit irrigation - Stomatal conductance - Transpiration rates - Water use efficiency Classification code:913.1 Production Engineering - 821.4 Agricultural Products - 821.0 Woodlands and Forestry - 741.1 Light/Optics - 461.9 Biology - 461.1 Biomedical Engineering - 446.1 Water Supply Systems DOI:10.6041/j.issn.1000-1298.2012.11.015 Database:Compendex 32. Accession number:20125115822674 Title:Experiment on water-swelling property of soil with application of water retention agent Authors:Han, Yuguo1 ; Fan, Yuntao2 ; Zhao, Lu3 ; Ding, Tao4 ; Xin, Xianhua4 Author affiliation:1 School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China 2 Chinese Academy of Agricultural Mechanization Sciences, Beijing 100083, China 3 Tancheng River Bureau, Yishuhe Water Resources Administrative Bureau, Tancheng 276100, China 4 Water Conservancy and Hydropower Survey and Design Institute of Inner Mongolia Bayannur City, Bayannur 015000, China Corresponding author:Han, Y. (yghan@bjfu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:74-79 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The soil with application of water retention agent was taken as an object to establish a model of porosity change, and the parameters of the model were calculated and verified by measuring the porosity of the soil under different moisture conditions. The model was found to have better simulation effects. On this basis, water-swelling property and porosity change of the soil with application of water retention agent were analyzed. The results show that the more water retention agent is applied, the more the soil swells and the more the porosity increases. Number of references:12 Main heading:Geologic models Controlled terms:Computer simulation - Porosity - Soils Uncontrolled terms:Moisture conditions - Porosity changes - Simulation effects - Water retention agents - Water-swelling Classification code:481.1 Geology - 483.1 Soils and Soil Mechanics - 723.5 Computer Applications - 931.2 Physical Properties of Gases, Liquids and Solids DOI:10.6041/j.issn.1000-1298.2012.11.014 Database:Compendex 33. Accession number:20125115822665 Title:Impact of combustion of BED blend fuel on diesel engine performance and emissions Authors:Lei, Jilin1 ; Shen, Lizhong1 ; Bi, Yuhua1 ; Tan, Zefei1 ; Chen, Hong1 ; Liu, Shaohua1 Author affiliation:1 Yunnan Province Key Laboratory of Engines, Kunming University of Science and Technology, Kunming 650224, China Corresponding author:Shen, L. (lzshen@foxmail.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:21-25 6 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:According to the physicochemical property complementarity of bio-ethanol, biodiesel and petroleum diesel, a multi-component fuel (BED fuel for short) with bio-ethanol, biodiesel and petroleum diesel was mixed. The compatibility and stability of the BED fuel were studied under four temperature (0°C, 10°C, 15°C, 20°C) environments. The relation between the engine performance and emissions and the six groups of BED fuel in different proportions were studied with the experiments. The results indicated that, the engine power with BED fuel greatly reduced at high loads in intermediate speed and the reducing amplitude raised with the increasing proportion of ethanol and bio-diesel components, the drop ratio was up to 10.2% compared with diesel. The equivalent brake specific fuel consumption (EBSFC for short) was lower than that of pure diesel. The change of EBSFC with BED fuel in different proportions did not show regularity at low loads, while the EBSFC reduced with the increasing oxygen content in BED fuel, the drop ratio was up to 9.2% compared with diesel. The CO emissions decreased significantly at high-loads and the biggest ratio was up to 70.1%. The NOx emissions rose with the increasing of bio-diesel component and reduced with the increasing ethanol component, the biggest raised ratio was up to 29% at rated working conditions. The THC emissions reduced with the increasing bio-diesel component and rose with the increasing ethanol component, the biggest decreasing ratio was up to 32.6% at rated working conditions. Number of references:10 Main heading:Diesel engines Controlled terms:Biodiesel - Bioethanol - Ethanol - Fuels Uncontrolled terms:Bio-ethanols - Blend fuels - Brake specific fuel consumption - CO emissions - Diesel engine performance - Emission characteristics - Engine performance - Engine power - High load - Low load - Multicomponent fuel - Oxygen content - Performance tests - Petroleum diesel - Physicochemical property Classification code:523 Liquid Fuels - 612.2 Diesel Engines DOI:10.6041/j.issn.1000-1298.2012.11.005 Database:Compendex 34. Accession number:20125115822687 Title:Optimization design of multi-stage submersible pump based on CFD Authors:Cui, Baoling1 ; Meng, Jiajia1 ; Jia, Xiaoqi1 Author affiliation:1 Province Key Laboratory of Fluid Transmission Technology, Zhejiang Sci-Tech University, Hangzhou 310018, China Corresponding author:Cui, B. (blcui@zstu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:142-146 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Combined with the characteristics of multi-stage submersible pump, the pump with sloping impeller and space guide vane was optimized using efficiency as optimization object. To improve the accuracy of numerical simulation, parametric fitting for sloping impeller and space guide vane was carried out. In the process of optimization, the blade inlet and outlet angle of the impeller and guide vane were considered as the control parameters. The range of angle was increased ±20°compared with the original model. Based on the successive flow field check, the optimal impeller model was obtained in the variation range of control parameters searching the optimum value of objective function based on genetic algorithm. The optimal model was obtained when inlet angle at the bottom of the blade was 35.53° and the outlet angle was 27.32°, the inlet angle of the guide vane was 15.48° and outlet angle was 61.75°. The pump efficiency increased by 4.12%, and the single stage head increased 1.449 m. The range of high efficiency has been extended, the stability of pump operation is improved, and the performance of the pump is optimized. Number of references:11 Main heading:Genetic algorithms Controlled terms:Computational fluid dynamics - Efficiency - Impellers - Optimization - Submersible pumps Uncontrolled terms:Control parameters - Guide vane - Impeller model - Inlet angles - Multi-stage - Objective functions - Optimal model - Optimization design - Optimum value - Original model - Outlet angle - Parametric fitting - Pump efficiency - Pump operation - Single stage Classification code:601.2 Machine Components - 618.2 Pumps - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 913.1 Production Engineering - 921 Mathematics DOI:10.6041/j.issn.1000-1298.2012.11.027 Database:Compendex 35. Accession number:20125115822704 Title:Optimization of job-shop resource configuration for minimizing manufacturing and tardiness cost Authors:Tang, Suzhou1 ; Gao, Yuan1 ; Wang, Delun1 ; Huang, Liang1 Author affiliation:1 School of Mechanical Engineering, Dalian University of Technology, Dalian 116024, China Corresponding author:Gao, Y. (gaoyuan@dlut.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:237-243 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In the discrete manufacturing environment of a job-shop, an optimization method for the resource configuration adjustment in order to minimize its manufacturing and tardiness cost was presented. With the material flow and work flow of a job-shop, a manufacturing process simulation model was first constructed to evaluate the performance of each resource configuration adjustment properly. Then by combining the production simulation method and improved simulated annealing algorithm, a solution algorithm for adjusting the resource amount of work centers and the production routings of products (or the configuration structure and usage way of resources) jointly was designed. In the proposed algorithm, the search and selection of neighbor configuration alternatives was guided by the critical production path analysis, and its convergence rate was then accelerated. It can gain better solution quality and efficiency than the traditional random search method, thus is more suitable for modeling and solving the large-scale resource configuration problem. Number of references:12 Main heading:Manufacture Controlled terms:Algorithms - Computer simulation - Costs - Optimization - Regression analysis Uncontrolled terms:Cost optimization - Critical Paths - Job-shop - Resource configurations - Simulated annealing algorithms Classification code:922.2 Mathematical Statistics - 921.5 Optimization Techniques - 921 Mathematics - 911 Cost and Value Engineering; Industrial Economics - 723.5 Computer Applications - 723 Computer Software, Data Handling and Applications - 537.1 Heat Treatment Processes DOI:10.6041/j.issn.1000-1298.2012.11.044 Database:Compendex 36. Accession number:20125115822677 Title:Analysis and experiment of distribution properties and its application of velocity in U-shaped open channel Authors:Yang, Shihong1 ; Han, Jinxu2 ; Peng, Shizhang1 ; Han, Dong3 Author affiliation:1 State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, Hohai University, Nanjing 210098, China 2 Yellow River Institute of Hydraulic Research, Zhengzhou 450003, China 3 State Center on Irrigation and Drainage, Beijing 100053, China Corresponding author:Peng, S. (szpeng@hhu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:92-96 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Based on indoor and field experiments, velocity distribution properties of U-shaped open channel were analyzed. Exponent formula for horizontal velocity distribution properties and two-power law for vertical velocity distribution properties were established. The methods to define the parameters were given. Then the midline three-point for flow measurement of open channel was put forward based on the velocity distribution properties of U-shaped channel. The fractional errors of flow velocities calculated by the midline three-point method in indoor experiment under different operating conditions and field experiment were within ±4% and ±5%, respectively. Validations showed that the midline three-point method increased the computational accuracy of flow measurement in open channel. In addition, the workload of the flow measurement by the midline three-point method was substantially reduced by more than 60% compared with velocity-section method which needed nine measuring points. Number of references:12 Main heading:Velocity distribution Controlled terms:Experiments - Flow measurement Uncontrolled terms:Computational accuracy - Distribution property - Field experiment - Fractional errors - Horizontal velocity - Indoor experiment - Irrigation districts - Measuring points - Open channels - Operating condition - Three-point methods - Two-power law - U-shaped - U-shaped channels - Vertical velocity distribution Classification code:901.3 Engineering Research - 943.2 Mechanical Variables Measurements DOI:10.6041/j.issn.1000-1298.2012.11.017 Database:Compendex 37. Accession number:20125115822668 Title:Experiment on response characteristics of variable cam phaser Authors:Zhang, Li1 ; Xie, Boqiang1 ; Jiang, Liang1 ; Yuan, Zhiqiang2 ; Fu, Qiubo2 ; Wang, Meng1 Author affiliation:1 College of Mechanical Engineering, Chongqing University, Chongqing 400044, China 2 Chang'an Automotive Engineering Institute, Chang'an Automobile Co., Ltd., Chongqing 401120, China Corresponding author:Zhang, L. (zhangli20@cqu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:36-40 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to study the response characteristics of variable cam phaser (VCP) under each operating parameter, a test bench was built up, and the methods for calculating the dynamic response time of VCP were put forward. The response time of the maximal VCP advance and retard position, under operating parameter include engine speed, hydraulic oil's pressure and temperature, can be measured. The experimental results indicate that response speed under the advance direction regulating of VCP is less than retard direction. Engine speed doesn't have much prominent effect on VCP response speed. As the increase of oil's temperature, the response speed become faster, but the rate of change is decreasing when the temperature higher than 70°C. The response speed augments as the oil's pressure increases, especially in low pressure (lower than 0.4 MPa). Number of references:8 Main heading:Speed Controlled terms:Cams - Dynamic response Uncontrolled terms:Engine speed - Experimental bench - Gasoline engines - Hydraulic oil - Low pressures - Operating parameters - Pressure and temperature - Pressure increase - Rate of change - Response characteristic - Response speed - Test benches - Variable cam phaser Classification code:408.1 Structural Design, General - 601.3 Mechanisms - 931.1 Mechanics DOI:10.6041/j.issn.1000-1298.2012.11.008 Database:Compendex 38. Accession number:20125115822700 Title:Segmentation method of agricultural products' X-ray image based on sum of neighborhood differences Authors:Guo, Wenchuan1 ; Liang, Wei1 ; Song, Huaibo1 Author affiliation:1 College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China Corresponding author:Guo, W. (guowenchuan69@126.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:214-219 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:In order to overcome the limitation of image segmentation methods based on 2-D histogram and modality in threshold techniques, a method based on the combination of the histogram concavity and the sum of the neighborhood differences was proposed. In addition, the comparative experiment was done when the proposed method and 2-D histogram methods were applied in segmentation on X-ray images of chestnuts, apples and kiwifruits. The results showed that the image segmentation error of the proposed method was less than 2.1%, and its biggest segmentation error was only 23.7% of that of 2-D histogram method. The proposed method could get the fruits' images more precisely. Number of references:17 Main heading:Graphic methods Controlled terms:Agricultural products - Fruits - Image segmentation - X ray analysis - X rays Uncontrolled terms:2-D histograms - Comparative experiments - Histogram concavity - Kiwifruits - Segmentation error - Segmentation methods - Sum of neighborhood differences - X-ray image Classification code:951 Materials Science - 932.1 High Energy Physics - 902.1 Engineering Graphics - 821.4 Agricultural Products - 801 Chemistry - 741.1 Light/Optics - 421 Strength of Building Materials; Mechanical Properties DOI:10.6041/j.issn.1000-1298.2012.11.040 Database:Compendex 39. Accession number:20125115822699 Title:Camellia fruit image recognition based on preference artificial immune net Authors:Li, Lijun1 ; Li, Xin1 ; Gao, Zicheng1 ; Zhou, Jian1 ; Min, Shuhui1 Author affiliation:1 College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China Corresponding author:Li, L. (junlili1122@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:209-213 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:With the demanding of morphological features recognition in picking robot machine-vision system, preference artificial immune net (aiNet) was used as the image recognition algorithm, mainly modified the structure of the algorithm to promote the accuracy rate. The algorithm was modified according to picking environment and real-time require. The simulation proved the clustering accuracy of preference aiNet reached to 81.67% in the sunny day and 87.69% in the cloudy day. The modified algorithm has certain meaning in the next research of picking robot. Number of references:19 Main heading:Image recognition Controlled terms:Algorithms - Computer vision - Fruits - Robots Uncontrolled terms:Accuracy rate - Artificial immune - Clustering accuracy - Machine vision systems - Modified algorithms - Morphological features - Picking robot - Recognition algorithm Classification code:716 Telecommunication; Radar, Radio and Television - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 731.5 Robotics - 821.4 Agricultural Products - 921 Mathematics DOI:10.6041/j.issn.1000-1298.2012.11.039 Database:Compendex 40. Accession number:20125115822695 Title:Optimization of vent configuration for ventilation dehumidification in multi-span plastic greenhouses Authors:He, Keshi1 ; Sun, Lijuan2 ; Huang, Zhenyu1 ; Liu, Zhenglu3 ; Chen, Dayue1 Author affiliation:1 School of Electronic Information and Electrical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China 2 Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing 100081, China 3 Sunqiao Modern Agricultural Development Zone, Shanghai 201210, China Corresponding author:Chen, D. (dychen@sjtu.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:186-191 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Multi-span plastic greenhouses mainly depend on solar heat storage. In winter, greenhouse is closed for prolonged periods for thermal insulation to avoid indoor heat being lost. Therefore, this would lead to indoor high humidity and consequently the occurrence of crop diseases. For making a good compromise between dehumidification effectiveness and indoor heat loss prevention, a full-scale computational fluid dynamics (CFD) model was developed based on an 11-span plastic greenhouse. Firstly, the model was validated by comparing experimental humidity with CFD simulations under roof ventilation. CFD simulations had similar trends to those of the experiments, with less than 5% difference. Then, the validated model was used to investigate the influences of vent configurations (i.e. side, roof and side plus roof) on the airflow pattern and humidity field inside the greenhouse. Simulations showed that roof ventilation tended to be the best. With the roof ventilation, dehumidification in the crop canopy could be achieved in 3min. After dehumidification, relative humidity was reduced from 92% to 68% and indoor humidity homogeneity was good. Moreover, responding heat loss was less. Therefore, this ventilation mode is able to meet the requirements of thermal insulation and dehumidification under winter climate conditions. Number of references:15 Main heading:Humidity control Controlled terms:Computational fluid dynamics - Crops - Greenhouses - Heat losses - Heat storage - Offshore pipelines - Roofs - Ventilation Uncontrolled terms:Airflow patterns - CFD simulations - Climate condition - Crop canopy - Crop disease - Dehumidification - High humidity - Multi-spans - Natural ventilation - Plastic greenhouse - Roof ventilation - Vent configurations - Ventilation mode Classification code:821.6 Farm Buildings and Other Structures - 821.4 Agricultural Products - 643.5 Ventilation - 921.6 Numerical Methods - 641.2 Heat Transfer - 402.1 Industrial and Agricultural Buildings - 402 Buildings and Towers - 619.1 Pipe, Piping and Pipelines DOI:10.6041/j.issn.1000-1298.2012.11.035 Database:Compendex 41. Accession number:20125115822672 Title:Evaporation experiments on layered water-repellent soil under perforated plastic mulch Authors:Li, Yi1 ; Ren, Xin2 Author affiliation:1 College of Water Resources and Architectural Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China 2 Accounts Bureau of Nanyang, Nanyang 473000, China Corresponding author:Li, Y. (liyikitty@126.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:58-64 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The perforated plastic mulch affects soil water movement in the heterogeneous field. Especially when soil water repellency degrees are different, the soil water movement process tends to be more complicated. Soil column evaporation experiments were conducted for Lou soil layered by sand and sand layered by Lou soil at various hydrophobic degrees under the controlled open-hole-ratio conditions. The soil water evaporation and soil moisture profiles at different conditions were measured and analyzed. The results showed that the curves of cumulative evaporation and time for full plastic mulch were obviously low, the corresponding soil moisture profile for ten days of evaporation was closed to the initial moisture profile, and this characteristic was more suitable to Lou soil layered by sand. When the open-hole-ratio increased, the cumulative evaporation of the two types of layered soil increased obviously compared with the full plastic mulch condition, showing the decreasing of mulching effects for conserving water even at small open-hole-ratios. When the water repellency degree increased, the cumulative evaporation decreased slightly, indicating the hydrophobicity of soils slowed down the water movement speed. When soil was seriously hydrophobic, hydrophobicity affected soil water movement more than open-hole-ratios. Logarithmic functions fit well for describing cumulative evaporation and time of various hydrophobic degrees of Lou soil layered by sand, while power functions and logarithmic functions were selected for sand layered by various hydrophobic degrees of Lou soils. Number of references:20 Main heading:Soil conservation Controlled terms:Evaporation - Experiments - Hydrophobicity - Phase transitions - Sand - Soil moisture Uncontrolled terms:Hydrophobic degrees - Initial moisture - Layered soils - Logarithmic functions - Open-hole-ratio - Plastic mulch - Power functions - Soil column - Soil moisture profiles - Soil water evaporation - Soil water movement - Soil water repellency - Water movements - Water repellency - Water-repellent soils Classification code:483.1 Soils and Soil Mechanics - 801.4 Physical Chemistry - 802.3 Chemical Operations - 901.3 Engineering Research - 931.2 Physical Properties of Gases, Liquids and Solids DOI:10.6041/j.issn.1000-1298.2012.11.012 Database:Compendex 42. Accession number:20125115822678 Title:Influence of soil physical and chemical properties on performance of soil profile moisture sensor Authors:Wang, Xinzhong1 ; Liu, Fei1 ; Han, Xu1 Author affiliation:1 Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang 212013, China Corresponding author:Wang, X. (wangxinzhong@gmail.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:97-101 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Aimed to the problem of measurement error influence of soil profile moisture sensor caused by variation of soil physical and chemical properties, the soil profile moisture sensor was firstly designed based on high frequency capacitor. And then the analysis was made through the experiments of sensor output voltage influenced by variation of soil physical and chemical properties such as soil temperature, electrical conductivity and bulk density. Thirdly, the soil moisture correction model based on the influence of temperature was established through statistics regression processing method. The performance of sensor was tested at last. The experiment results showed that the sensor output voltage linearly increased with soil temperature changes ranged from 5°C to 45°C, and it decreased with electrical conductivity increasing when the electrical conductivity was greater than 2mS/cm. Moreover, the sensor output voltage showed a decreasing trend with bulk density increasing. The largest measuring absolute error was 4.70%, root-mean-square error was 0.025 24 and correlation coefficient R2 was 0.967 9 through comparing the measuring value between sensor and traditional drying method at normal temperature. Number of references:17 Main heading:Sensors Controlled terms:Chemical properties - Electric conductivity - Experiments - Moisture meters - Soil moisture - Temperature Uncontrolled terms:Absolute error - AS-soils - Bulk density - Correction models - Correlation coefficient - Drying methods - Electrical conductivity - High frequency - Moisture sensors - Processing method - Profile - Root-mean square errors - Sensor output - Soil moisture sensors - Soil physical and chemical properties - Soil profiles - Soil temperature Classification code:944.1 Moisture Measuring Instruments - 901.3 Engineering Research - 801 Chemistry - 701.1 Electricity: Basic Concepts and Phenomena - 641.1 Thermodynamics - 483.1 Soils and Soil Mechanics - 423 Non Mechanical Properties and Tests of Building Materials DOI:10.6041/j.issn.1000-1298.2012.11.018 Database:Compendex 43. Accession number:20125115822673 Title:Effects of EN-1 soil stabilizer on water vertical infiltration characteristics for loess stabilized soil Authors:Liu, Yuemei1, 2 ; Zhang, Xingchang3 Author affiliation:1 College of Resources and Environment, Northwest A and F University, Yangling, Shaanxi 712100, China 2 Yanan Vocational and Technical College, Yan'an 716000, China 3 Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, Shaanxi 712100, China Corresponding author:Zhang, X. (zhangxc@ms.iswc.ac.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:65-73 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Characteristics and dynamic changes of soil water infiltration under different soil bulk density and different stabilizer content were analyzed by one-dimensional vertical infiltration experiments. The results showed that soil bulk density had significant influences on infiltration capacity of stabilized soil from 1.2~1.4 g/cm3 of soil bulk density ranged. The influences of soil bulk density on infiltration rate were stable and constituent. With increasing soil bulk density, cumulative infiltration decreased. Stabilizer amendment amount had effects on cumulative infiltration and wetting front under the same soil bulk density. Cumulative infiltration were the highest at 0.05%~0.1% amendment amount of EN-1stabilizer, and were higher the control. There was good linear relationship between the amount of cumulative infiltration and the wetting front distance. With increasing amendment amount of EN-1stabilizer, cumulative infiltration and wetting front had trend of increase first and decrease then. Fitting the relationship between infiltration rate and time with Philip model, Kostiakov empirical formula and index formula, the results showed Kostiakov formula was more accurate than other models and fitted values of its had the best results at higher soil bulk density. Number of references:27 Main heading:Infiltration Controlled terms:Geologic models - Mathematical models - Soil conditioners - Soil moisture - Wetting Uncontrolled terms:Dynamic changes - Empirical formulas - Fitted values - Index formula - Infiltration capacity - Infiltration rate - Linear relationships - Soil bulk density - Soil stabilizers - Soil water - Stabilized soils - Vertical infiltration - Wetting fronts Classification code:481.1 Geology - 483.1 Soils and Soil Mechanics - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids DOI:10.6041/j.issn.1000-1298.2012.11.013 Database:Compendex 44. Accession number:20125115822697 Title:Inspiring effect of locust's phototactic response stimulated by light-sound-vibration coupling Authors:Liu, Qihang1 ; Zhou, Qiang2 Author affiliation:1 School of Mechanical Engineering, Hebei University of Engineering, Handan 056038, China 2 College of Engineering, China Agricultural University, Beijing 100083, China Corresponding author:Liu, Q. (bjliuqihang@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:197-202 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:According to locust's response characteristic stimulated by light, sound and vibration, the experiment of locust's phototactic response stimulated by light-sound-vibration coupling effect was carried out by using the designed experimental equipment. The results showed that light-sound-vibration coupling stimulated locust's phototactic effect. The stimulation effect of its pull-push and drive could realize locust's phototactic induction effectively. The illumination of combined spectrum decided locust's phototactic aggregation. The illumination increased by 10 times, the effect of locust's phototactic aggregation stimulated by light-sound-vibration coupling increased by 25%. Within a certain range, light-sound-vibration stimulated locust's phototactic direction response effectively. The regulative spectrum illumination leaded to locust's phototactic response. Vibration decided the driving stimulation of locust's phototactic response. The audio frequency played the important role in gain motivation. Light-sound-vibration signal stimulated locust's multiple receptors and generated the superimposition effect contributing to locust's phototactic aggregation, so locust's phototactic induction effect could be enhanced effectively through combining different audio frequency mode, regulatory mode of spectral illumination and circulating vibration mode. Number of references:12 Main heading:Audio acoustics Controlled terms:Agricultural engineering - Mechanical engineering Uncontrolled terms:Audio frequencies - Coupling effect - Experimental equipments - Inspiring effect - Locusts - Multiple receptors - Phototactic response - Response characteristic - Spectrum illuminations - Vibration modes Classification code:608 Mechanical Engineering, General - 751.1 Acoustic Waves - 821 Agricultural Equipment and Methods; Vegetation and Pest Control DOI:10.6041/j.issn.1000-1298.2012.11.037 Database:Compendex 45. Accession number:20125115822701 Title:Weed recognition from pea seedling images and variable spraying control system Authors:Zhang, Xiaolong1 ; Xie, Zhengchun1 ; Zhang, Niansheng1 ; Cao, Chengmao1 Author affiliation:1 School of Engineering, Anhui Agricultural University, Hefei 230036, China Corresponding author:Cao, C. (caochengmao@sina.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:220-225 73 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:The application system of real-time image recognition and variable spraying was designed based on the virtual image real-time controller CVS-1456. The original images, which contained pea seedlings, soil background, weed of cephalanoplos segetum, etc, were collected in normal sunlight. The color models of original images were analyzed and real-time weed recognition was realized based on R-B color features by using LabVIEW software and IMAQ Vision toolbox. The Canny algorithm was employed to detect weed edges, and three characteristic parameters of target weed, namely area, density, centroidal position, were extracted to provide positioning evidences for variable spraying. The random tests verified the accuracy and reliability of the purposed cephalanoplos segetum recognition method from complex background images based on R-B color features, in which the average right recognition rate was 83.5%, mean square deviation 0.066. Number of references:11 Main heading:Color Controlled terms:Color image processing - Computer programming languages - Edge detection - Real time systems Uncontrolled terms:Application systems - Canny algorithm - Characteristic parameter - Color features - Color models - Complex background - LabVIEW software - Mean square deviation - Original images - Pea seedlings - Random tests - Real-time controllers - Recognition methods - Recognition rates - Virtual images - Weed recognition Classification code:722.4 Digital Computers and Systems - 723.1.1 Computer Programming Languages - 741.1 Light/Optics DOI:10.6041/j.issn.1000-1298.2012.11.041 Database:Compendex 46. Accession number:20125115822707 Title:Axial stiffness identification of support point for ball screw based on principle of initial parameter method Authors:Hu, Feng1 ; Wu, Bo2 ; Shi, Tielin2 Author affiliation:1 School of Mechanical Science and Engineering, Wuhan Textile University, Wuhan 430073, China 2 School of Mechanical Science and Engineering, Huazhong University of Science and Technology, Wuhan 430074, China Corresponding author:Hu, F. (wuhanhufeng@163.com) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:256-260 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:A new method for evaluating the axial stiffness of ball screw at support point was proposed. Based on principle of initial parameter method, the initial parameter matrix equation was established for force and displacement of ball screw. The structural characters, including boundary condition, force balance and displacement compatibility at support point, were used to achieve initial parameter values. As a result, axial force and displacement of every point on ball screw could be obtained. The identification models of axial stiffness were built by analyzing the amplitude changes of ball screw under some load affection employing the knowledge of mechanical vibration and material mechanics. The research results are in good agreement with the results obtained by the available experiments. Number of references:11 Main heading:Identification (control systems) Controlled terms:Ball screws - Matrix algebra - Parameter estimation - Screws - Stiffness Uncontrolled terms:Axial forces - Axial stiffness - Displacement compatibility - Force balances - Identification model - Initial parameter - Material mechanics - Research results - Structural character Classification code:951 Materials Science - 921.1 Algebra - 732.1 Control Equipment - 731.1 Control Systems - 605 Small Tools and Hardware - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties DOI:10.6041/j.issn.1000-1298.2012.11.047 Database:Compendex 47. Accession number:20125115822666 Title:Features of burning flames and heat release process of biodiesel engine Authors:Mei, Deqing1 ; Yuan, Yinnan2 ; Sun, Ping1 ; Wang, Zhong1 Author affiliation:1 School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China 2 School of Mechanical Engineering, Nantong University, Nantong 226019, China Corresponding author:Mei, D. (meideqing@ujs.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:26-30 20 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:With the aim to reveal the difference of combustion and heat release process in cylinder of engine fueled with soya methyl ester and petroleum diesel, high speed photography was used to catch combustion flame images in cylinder and thereafter the pressure indicator diagram was collected to compute the heat release rate. The combustion processes of biodiesel and petrolic diesel were illustrated in the crank angle coordinate with the direct flame images combined with analysis of heat release. Due to the contribution of bigger bulk modulus and higher cetane number of biodiesel, the beginning of injection for biodiesel was 0.7°CA earlier than that for diesel, and the ignition time of biodiesel occurred earlier 1.5°CA than that of diesel, under the unimproved conditions of fuel supply system. During the rapid combustion period, both the brightness and its lasting time of biodiesel were less than that of diesel. The heat released by the chemical reactions without obvious flame at the end of combustion only accounted for 2%~3% of the total cycle heat energy released by fuel. Number of references:12 Main heading:Combustion Controlled terms:Biodiesel - Diesel engines - Engine cylinders - High speed photography Uncontrolled terms:Combustion flames - Combustion pro-cess - Crank angle - Flame images - Fuel supply systems - Heat energy - Heat release - Heat Release Rate (HRR) - Ignition time - Lasting time - Methyl esters - Petroleum diesel - Pressure indicator Classification code:521.1 Fuel Combustion - 523 Liquid Fuels - 612.1.1 Internal Combustion Engine Components - 612.2 Diesel Engines - 742.1 Photography DOI:10.6041/j.issn.1000-1298.2012.11.006 Database:Compendex 48. Accession number:20125115822702 Title:Design of self-propelled precise feeding machine control system for single dairy cow Authors:Gao, Zhenjiang1 ; Guo, Yuehu1 ; Meng, Hewei2 ; Li, Hui1 ; Li, Shoubo1 ; Chen, Tianming1 Author affiliation:1 College of Engineering, China Agricultural University, Beijing 100083, China 2 College of Mechanical and Electrical Engineering, Shihezi University, Shihezi 832003, China Corresponding author:Gao, Z. (zjgao@cau.edu.cn) Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society of Agricultural Machinery Abbreviated source title:Nongye Jixie Xuebao Volume:43 Issue:11 Issue date:November 2012 Publication year:2012 Pages:226-230 236 Language:Chinese ISSN:10001298 CODEN:NUYCA3 Document type:Journal article (JA) Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China Abstract:Based on the technology of personal computer and wireless transmission, a kind of self-propelled precise feeding machine control system for single dairy cow was designed. This kind of control system can realize the precise feeding of single dairy cow based on their physiological characteristics by using the technology of RFID and MCU. Using this system, the intelligent identification for single dairy cow and the information transmitted from personal computer to MCU by air were realized. The dual-mode moving and accurate feeding was achieved. The experimental results showed that the best rate of the precise feeding machine was 0.6 m/s. The response time of the machine was 0.4 s. The control system can identify 96% of the single dairy cow correctly. The feeding error was controlled at below 2%. Number of references:10 Main heading:Control systems Controlled terms:Feeding - Personal computers Uncontrolled terms:Cow - Dairy cow - Dual modes - Feeding error - Intelligent identification - Machine control systems - Physiological characteristics - Self-propelled - Wireless transmissions Classification code:691.2 Materials Handling Methods - 722.4 Digital Computers and Systems - 731.1 Control Systems DOI:10.6041/j.issn.1000-1298.2012.11.042 Database:Compendex
|