2014年第45卷第3期共收錄55篇
1. Accession number:20141717619066
Title:Experiment on relationships between centrifugal pump cavitation conditions and acoustic emission signal characteristics
Authors:Zou, Shuyun1 ; Liu, Zhong1 ; Li, Zhipeng1 ; Yang, Ping2
Author affiliation:1 School of Energy and Power Engineering, Changsha University of Science and Technology, Changsha 410114, China
2 School of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha 410004, China
Corresponding author:Liu, Z. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:45-48 44
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to obtain the variation law of the acoustic emission signals under the centrifugal pump's cavitation states, the research was based on the centrifugal pump cavitation test. The acoustic emission technology was adopted to collect and analyze the acoustic emission signals. Four typical features were extracted, i.e. event count, ringing count, frequency centroid and root mean square. Their relationships with the net positive suction heads of the centrifugal pump were analyzed in detail. The results show that these typical characteristic parameters change obviously under different stages such as before the occurrence of cavitation, cavitation first appearing and cavitation being fully developed. They firstly fluctuate a little, then increase or decrease substantially, and then there are large reducing or increasing trends respectively. This law can be used as a technical basis for identifying the cavitation conditions of centrifugal pumps with the acoustic emission technique.
Number of references:18
Main heading:Centrifugal pumps
Controlled terms:Acoustic emissions - Cavitation - Rockets
Uncontrolled terms:Acoustic emission signal - Acoustic emission techniques - Cavitation conditions - Different stages - Emission technology - Net positive suction heads - Parameter analysis - Root Mean Square
Classification code:404.1 Military Engineering - 618.2 Pumps - 631.1.1 Liquid Dynamics - 751.2 Acoustic Properties of Materials
DOI:10.6041/j.issn.1000-1298.2014.03.008
Database:Compendex
2. Accession number:20141717619100
Title:Inversion model of Pinus massoniana leaf area index based on HJ-1
Authors:Lai, Riwen1 ; Liu, Jian1, 2 ; Xu, Zhanghua1, 2 ; Wang, Qin1
Author affiliation:1 College of Forestry, Fujian Agriculture and Forestry University, Fuzhou 350002, China
2 Institute of Geomatics Application, Fujian Agriculture and Forestry University, Fuzhou 350002, China
Corresponding author:Lai, R. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:255-261
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Taking Fujian province as the research object and basing on the CCD data of HJ-1, four vegetation indices were selected which closely related to LAI. The selected indices included NDVI, RVI, mSAVI and EVI. Meanwhile, data synchronized with LAI of Pinus massoniana was obtained, and then the relationship between the indices and the LAI was built. At last, six kinds of the non-linear regression models, between the LAI of Pinus massoniana and the selected index RVI that most closely related to the LAI, was established. It was found that the model based on the Richards distribution function is the best and the relative error of the prediction of mean value is 3.1%. Based on this model, the remote sensing inversion of the LAI of Pinus massoniana in Fujian province was implemented.
Number of references:19
Main heading:Forestry
Controlled terms:Regression analysis - Remote sensing - Vegetation
Uncontrolled terms:Fujian Province - Inversion models - Leaf Area Index - Model-based OPC - Non-linear regression - Pinus massoniana - Relative errors - Vegetation index
Classification code:731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2014.03.042
Database:Compendex
3. Accession number:20141717619079
Title:Design and performance experiment of anti-clogging of subsurface drip irrigation system
Authors:Yu, Kun1 ; Yu, Songlin1 ; Fu, Xiaofa2 ; Xu, Wenbo1 ; Wang, Qingfeng1
Author affiliation:1 College of Agronomy, Shihezi University, Shihezi 832003, China
2 Xinjiang Academy of Agricultural Sciences, Urumqi 830091, China
Corresponding author:Yu, S. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:124-128
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to solve the problem of congestion in subsurface drip irrigation and to promote application of subsurface drip irrigation to forest or fruit industry, the design principle and the design requirements of model anti-clogging of subsurface drip irrigation system were proposed. These data of the system were obtained that the system pressure was 15~25 kPa and the plughole spacing was 300 mm, and that the distance between inner wall of protective tube and out wall of capillary was 40 mm and the irrigation uniformity is more than 85% through experiment. Effects on the growth of Cabernet Sauvignon by the system show that anti-clogging subsurface drip irrigation (SDI) and drip irrigation under plastic film (MDI) compared with conventional drip irrigation (DI) can maintain the stability of soil moisture content in 20~60 cm, and increase ratio of root to shoot and the effective root surface area, so as to accelerate root turnover and renewal, and enhance the absorptive capacity of plant roots to soil moisture and nutrient.
Number of references:13
Main heading:Subirrigation
Controlled terms:Design - Experiments - Soil moisture - Wine
Uncontrolled terms:Absorptive capacity - Anti-dogging - Cabernet-Sauvignon - Design Principles - Drip irrigation under plastic films - Irrigation uniformity - Performance experiment - Subsurface drip irrigation
Classification code:408 Structural Design - 483.1 Soils and Soil Mechanics - 821.3 Agricultural Methods - 822.3 Food Products - 901.3 Engineering Research
DOI:10.6041/j.issn.1000-1298.2014.03.021
Database:Compendex
4. Accession number:20141717619072
Title:Effects of channel with M-type section on the performance of vortex pump
Authors:Wang, Yang1 ; Li, Yacheng1 ; Cao, Puyu1 ; Liu, Yang1 ; Lü, Zhongbin1
Author affiliation:1 Technical and Research Center of Fluid Machinery Engineering, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Wang, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:77-82
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:An M-type section had been designed to reduce internal shock losses in the channel of votex pump. The reasonable M section was based on the theory of the same area, with the constant height, section of channel sharped like an M was more in line with law of fluid flow. The nearest distance of the wall of channel and the outlet of blades was 1 mm. In order to research the inner flow in channel, computational fluid dynamics software CFX was adopted in the inner flow field analysis. Head, efficiency curve and velocity vector of rectangular and M-type channel were obtained from the simulation. The results show that the head and efficiency have improved; fluid flows more smoothly in the M-type channel; turbulence and small reverse spiral at the outlet of blades is less. However, the friction losses increase with the larger flow area.
Number of references:15
Main heading:Flow of fluids
Controlled terms:Computational fluid dynamics - Computer simulation - Friction
Uncontrolled terms:Channel - Computational Fluid Dynamics software - Efficiency curves - Friction loss - Inner flow field - Shock loss - Velocity vectors - Vortex pumps
Classification code:723.5 Computer Applications - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2014.03.014
Database:Compendex
5. Accession number:20141717619064
Title:Gasoline engine charge-efficiency measuring based on fuel consumption and AFR test
Authors:Wan, Liping1 ; Jiang, Yankun1 ; Guo, Yan1 ; Zhang, Jianping1 ; Liu, Xin1
Author affiliation:1 School of Energy and Power Engineering, Huazhong University of Science and Technology, Wuhan 430074, China
Corresponding author:Jiang, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:32-36 25
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:This essay describes a new method, based on fuel consumption and AFR (Air-fuel ratio) measuring, to acquire the charge efficiency of internal combustion engine. In the method, the fuel consumption and AFR under steady condition are used to calculate the air inlet, and the air charge efficiency is calculated by definition. The equations of air charge efficiency and error analysis were built on fuel consumption and AFR. An injector flux calibration & testing system and a measuring system of fuel consumption and AFR were designed for a ZS157FMI-3 motor equipping with ZH600 engine electronic control system. The charge efficiency was tested through measuring mean and transient fuel consumptions and AFR. The efficiency test result indicates that the two methods of measuring fuel consumption have a good consistence for charge efficiency calculation, and the error estimation of the test results demonstrates that the efficiency results calculated from the fuel consumption and AFR have high accuracy, with the relative error below 0.5%. Since the charge efficiency acquiring way overcomes some inherent drawbacks of the common methods such as pressure wave method and velocity-pressure method, it offers more measure accurate in theory and better adaptability to different fuel types.
Number of references:16
Main heading:Efficiency
Controlled terms:Control - Engines - Fuel consumption - Gasoline - Internal combustion engines
Uncontrolled terms:Accuracy - AFR - Charge efficiency - Engine electronic control system - Gasoline engines - Measuring systems - Steady conditions - Velocity-pressure
Classification code:521 Fuel Combustion and Flame Research - 523 Liquid Fuels - 612 Engines - 612.1 Internal Combustion Engines, General - 731 Automatic Control Principles and Applications - 732 Control Devices - 913.1 Production Engineering
DOI:10.6041/j.issn.1000-1298.2014.03.006
Database:Compendex
6. Accession number:20141717619103
Title:Weed recognition in agricultural field using multiple feature fusions
Authors:Zhao, Peng1 ; Wei, Xingzhu1
Author affiliation:1 Information and Computer Engineering College, Northeast Forestry University, Harbin 150040, China
Corresponding author:Zhao, P. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:275-281
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A novel weed recognition scheme based on fuzzy BP overall neural network is proposed. First, the classification features are blurred to deal with the uncertainty of weed features. Second, the genetic algorithm is used to optimize the network structure so as to improve the network's convergence and stability. Finally, a feature-level data fusion scheme is used. In weed species identification experiments, neural network consists of the 4 BP sub-networks on color feature, main texture feature, secondary texture feature and spectral feature. The results indicate that the overall recognition rate reaches to a good recognition accuracy of 94.2% for 7 weed species. Besides, experiments were put into effect on the corn and its accompanying weeds. The neural network consists of the 4 BP sub-networks on color feature, main texture feature, height feature and spectral feature. The recognition rate reaches to 96.7% with a better recognition accuracy.
Number of references:20
Main heading:Neural networks
Controlled terms:Agricultural machinery - Computer vision - Data fusion - Experiments - Spectrum analysis - Speech recognition - Textures
Uncontrolled terms:Agricultural fields - BP neural networks - Classification features - Convergence and stability - Multiple feature fusion - Network structures - Recognition accuracy - Weed recognition
Classification code:723 Computer Software, Data Handling and Applications - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 921 Mathematics - 933 Solid State Physics - 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.1000-1298.2014.03.045
Database:Compendex
7. Accession number:20141717619062
Title:Spray break-up model of multi-hole injector on gasoline direct injection engine
Authors:Wang, Yanhua1, 2 ; Gao, Feng2 ; Yang, Shichun2 ; Xu, Junfeng1 ; Liu, Hantao1
Author affiliation:1 School of Mechanical and Power Engineering, North University of China, Taiyuan 030051, China
2 School of Transportation Science and Engineering, Beihang University, Beijing 100191, China
Corresponding author:Wang, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:20-25
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to establish break-up model of multi-hole injection on gasoline direct injection engine, an analysis and evaluation on FIPA model, Huh Gosman model and KH-RT model has been done. The second break-up model was built for gasoline direct injection in cylinder, and the primary break-up particle size distribution formula was also built based on injection pressure. So the break-up model of gasoline direct injection in cylinder was established. At last, by carrying out capacity spray experiments, gasoline free spray experiments were done to verify the reasonability of the established model. It was found that Huh Gosman model has the best simulation results compared with other models. The droplets break relatively too fast with FIPA model and too slowly with KH-RT under the same simulation condition. After modifying Huh Gosman model, the simulation results showed close to the practical ones. At last, free sprays under different injection pressures were simulated with the above established model. Calculation results match well with the experimental results.
Number of references:15
Main heading:Computer simulation
Controlled terms:Direct injection - Engines - Experiments - Gasoline - Particle size analysis
Uncontrolled terms:Analysis and evaluation - Calculation results - Free spray - Gasoline direct injection - Gasoline direct injection engines - Injection pressures - Multi-hole injectors - Reasonability
Classification code:521 Fuel Combustion and Flame Research - 523 Liquid Fuels - 612 Engines - 723.5 Computer Applications - 901.3 Engineering Research - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2014.03.004
Database:Compendex
8. Accession number:20141717619089
Title:Numerical study on blade dynamic stall of vertical axis wind turbine
Authors:Mei, Yi1 ; Qu, Jianjun1 ; Xu, Mingwei1
Author affiliation:1 School of Mechatronics, Harbin Institute of Technology, Harbin 150001, China
Corresponding author:Qu, J. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:184-190
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The blade dynamic stall behavior of a vertical axis wind turbine with high height to radius ratio was studied using a numerical method. The numerical modeling technique reliability was validated through a comparison of the computational results with the wind tunnel measurement. Below constant wind condition 8 m/s, combined with the velocity vector and vorticity contours, the dynamic stall behavior and the rotor power performance were investigated with different tip speed ratios and variant turbine configurations. Illustrated by the simulation, lowering the tip speed ratio and increasing the rotor cord to radius ratio and the blade number will enhance the vortex generation and the flow separation on blades, leading to significant degradation of turbine performance. It can be concluded from the numerical analysis, a vertical axis wind turbine with high height to radius ratio applied in urban area will experience a better performance when operating in the optimal tip speed ratio, with rotor cord to radius ratio between 0.2 and 0.4, and 3 or 4 blades.
Number of references:16
Main heading:Wind turbines
Controlled terms:Computer simulation - Numerical models - Turbulence models
Uncontrolled terms:Better performance - Computational results - Dynamic stalls - Sliding mesh - Turbine performance - Vertical axis wind turbines - Vortex generation - Wind tunnel measurements
Classification code:443.1 Atmospheric Properties - 615.8 Wind Power (Before 1993, use code 611 ) - 723.5 Computer Applications - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.031
Database:Compendex
9. Accession number:20141717619082
Title:Root distribution in strip intercropping field under different growth period and different soil water
Authors:Li, Xianyue1 ; Shi, Haibin1 ; Gong, Xuewen1 ; Peng, Zunyuan1 ; Li, Zhen1 ; Yan, Jianwen1
Author affiliation:1 College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Huhhot 010018, China
Corresponding author:Shi, H. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:140-147
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:It is the primary factor to influence the completion and utilization efficiency of water and fertilizer for the root distribution in strip intercropping field. The effects of 3 treatments of high, middle and low irrigation quotas on soil water of different positions and root distribution were studied, and the characteristics of root distribution in different growth period were investigated, as well as the pattern of root distribution in vertical and horizontal direction based on cumulative root distribution curves. The results show that the average soil water in tomato side is obviously higher than corn side, and the soil water under mulch is also obviously higher than that under outside mulch; however, there is no significant difference for the soil water of different positions under mulch. With crop growth, there are the pattern of "no cross-small cross-full cross-small cross" for roots of tomato and corn; 60%~70% root concentrates in 0~30 cm soil, and the quantity of total roots and the roots in 0~30 cm soil are all increasing with the soil water, whatever root length density, root surface area density, root volume density and root weight density, yet there is the inverse for root distribution in 40~100 cm soil. The cumulative root distribution curves show that the root grows down with the soil water increase and the root grows to the district among crops with crop growth except for corn in the last stage. The root distribution is large variation in different growth periods, and the soil water is also main factor to influence root distribution in strip intercropping field.
Number of references:18
Main heading:Forestry
Controlled terms:Crops - Fruits - Plants (botany) - Soil moisture
Uncontrolled terms:Irrigation quotas - Primary factors - Root distribution - Root length density - Root surface area - Soil water - Strip intercropping - Utilization efficiency
Classification code:461.9 Biology - 483.1 Soils and Soil Mechanics - 821.0 Woodlands and Forestry - 821.4 Agricultural Products
DOI:10.6041/j.issn.1000-1298.2014.03.024
Database:Compendex
10. Accession number:20141717619097
Title:Sows parturition detection method based on machine vision
Authors:Liu, Longshen1 ; Shen, Mingxia1 ; Bo, Guangyu1 ; Zhou, Bo2 ; Lu, Mingzhou1 ; Yang, Xiaojing3
Author affiliation:1 College of Engineering, Nanjing Agricultural University, Nanjing 210031, China
2 College of Animal Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
3 Key Lab. of Animal Physiology and Biochemistry, Ministry of Agriculture, Nanjing Agricultural University, Nanjing 210095, China
Corresponding author:Shen, M. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:237-242
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Automation and industrialization is the trend of pig industry. Real-time detection of parturition is one of the key technologies of sow automation farming. Video image features of sows parturition were analyzed to detect sows parturition by recognizing piglet. The moving objects were detected based on the improved single Gaussian model. Disturbance of sow moving was removed by the arithmetic of matching semi-circle. According to the color and size characteristics of newborn piglets, targets were recognized. Test results showed that the sow object could be recognized effectively by the proposed approach. The moving objects detection method based on the improved single Gaussian model detected the slow-moving piglet completely after eliminate interference.
Number of references:17
Main heading:Computer vision
Uncontrolled terms:Detection methods - Key technologies - Matching by semi-circle - Moving objects - Moving objects detection - Real-time detection - Single Gaussian model - Sows parturition
Classification code:723.5 Computer Applications
DOI:10.6041/j.issn.1000-1298.2014.03.039
Database:Compendex
11. Accession number:20141717619101
Title:Damage pattern recognition of Citrus reticulate Blanco based on multi-fractal analysis of image hue
Authors:Wen, Zhiyuan1 ; Cao, Leping2
Author affiliation:1 College of Science, Hunan Agricultural University, Changsha 410128, China
2 Hunan Biological and Electromechanical Polytechnic, Changsha 410127, China
Corresponding author:Cao, L. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:262-267
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The investigation proposed a new algorithm to automatize the identification process of pests and insects disease of Citrus reticulata Blanco var. Ponkan, in which multi-fractal spectra of image hue were set as inputs of wavelet neural network model. In the new algorithm, image boundary of damage pattern of Ponkan was extracted with improved watershed algorithm, and discontinuous boundary was processed with boundary following, meanwhile over-segmentation region was merged and boundary was marked, at last, damage pattern image was generated. After the work above, firstly, hue range 0°~120° of damage pattern image was equally segmented into 4 regions to generate 4 binary images. And then these binary images were analyzed by multi-fractal method to calculate the widths and heights of multi-fractal spectra of scale invariance region. In the end, the widths and heights of multi-fractal spectra were set as the inputs of wavelet neural network model to identify the pest and insects disease of citrus fruit. Test results showed that the accurate rate of identification of 5 pests and insects disease is about 87%, which means that widths and heights of multi-fractal spectra are sufficient to characterize the damage pattern of citrus fruit, and this method is applicable in machine automatic recognition for pests and insects disease of citrus fruit.
Number of references:19
Main heading:Fractals
Controlled terms:Algorithms - Binary images - Citrus fruits - Computer vision - Image recognition
Uncontrolled terms:Automatic recognition - Citrus reticulata Blanco - Citrus reticulate Blanco - Identification process - Multi fractals - Water-shed algorithm - Wavelet neural network model - Wavelet neural networks
Classification code:716 Telecommunication; Radar, Radio and Television - 723.2 Data Processing and Image Processing - 723.5 Computer Applications - 821.4 Agricultural Products - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.043
Database:Compendex
12. Accession number:20141717619092
Title:Thermal behaviors and ice crystal properties in pressure shift freezing of beef
Authors:Su, Guangming1 ; Ramaswamy, Hosahalli S.2 ; Yu, Yong1 ; Hu, Feifei1 ; Xu, Menglong1 ; Zhu, Songming1
Author affiliation:1 College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
2 Department of Food Science and Agricultural Chemistry, McGill University, Montreal H9X3V9, Canada
Corresponding author:Zhu, S. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:206-214
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The experiments of pressure shift freezing (PSF) and conventional freezing were conducted on beef, and the thermal behaviors and ice crystal properties in freezing process were analyzed. The PSF experiments at 100 MPa (-9°C), 150 MPa (-15°C) and 200 MPa (-20°C) were performed as well as conventional air freezing (CAF) and liquid immersion freezing (LIF) at -20°C and 0.1 MPa. The results show that most of the ice crystals formed in conventional freezing is extracellular, the size is large and non-uniform, and severe strain and mechanical injuries has happened on the tissue cells. The crystals formed in PSF have smaller and more uniform size and spread more evenly in samples than that in conventional freezing. And the higher the pressure was, the more crystals formed in intracellular spaces and the less cell injuries happened. The freezing time in CAF is 85 min, in LIF is 5.5 min, and is 2.47, 1.22 and 0.83 min when subjecting to 100, 150 and 200 MPa PSF treatments; the degree of supercooling formed in depressurization increases with pressure increasing. However, the freezing point drops with and the freezing time needed reduces with the pressure increasing.
Number of references:34
Main heading:Ice
Controlled terms:Beef - Enzyme activity - Experiments - Freezing - Meats - Room and pillar mining
Uncontrolled terms:Degree of supercooling - Depressurizations - Ice crystals - Intracellular spaces - Liquid immersion - Mechanical injury - Pressure shift freezing - Thermal behaviors
Classification code:443 Meteorology - 461.9 Biology - 502.1 Mine and Quarry Operations - 822.2 Food Processing Operations - 822.3 Food Products - 901.3 Engineering Research
DOI:10.6041/j.issn.1000-1298.2014.03.034
Database:Compendex
13. Accession number:20141717619059
Title:Nonlinear model-based position servo control of electro-pneumatic clutch actuator
Authors:Qian, Pengfei1 ; Tao, Guoliang1 ; Meng, Deyuan1 ; Zhu, Xiao1 ; Liu, Hao1 ; Li, Qingwei1
Author affiliation:1 State Key Laboratory of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China
Corresponding author:Tao, G. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:1-6 12
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to realize the servo control of electro-pneumatic clutch actuator in an automated mechanical transmission, an electro-pneumatic clutch actuator system was established. By performing a simple sliding mode control law of dead zone directly on the established system, the tracking control of the electro-pneumatic clutch actuator without unnecessary control chattering was achieved. Meanwhile, the load characteristics of clutch could be estimated indirectly by the pneumatic driving force during trajectory tracking. In theory, the estimation error of load characteristics obtained by this approach is small. So, the clutch load characteristic is closer to the actual value in the trajectory-tracking control. Tests show that the proposed model-based integral sliding-mode controller with the estimation of clutch load characteristic introduced can improve the tracking accuracy to a large extent.
Number of references:13
Main heading:Loads (forces)
Controlled terms:Actuators - Clutches - Navigation - Pneumatic control equipment - Sliding mode control - Transmissions
Uncontrolled terms:Automated mechanical transmissions - Electropneumatic - Integral sliding mode - Load characteristics - Position servo
Classification code:408 Structural Design - 421 Strength of Building Materials; Mechanical Properties - 602.2 Mechanical Transmissions - 632 Hydraulics, Pneumatics and Related Equipment, and Fluidics - 632.4 Pneumatic Equipment and Machinery - 716.3 Radio Systems and Equipment - 731.1 Control Systems
DOI:10.6041/j.issn.1000-1298.2014.03.001
Database:Compendex
14. Accession number:20141717619086
Title:Relatively high-substrate consistency hydrolysis of hydrothermal pretreated Jerusalem artichoke stalk with H2SO3 catalysis
Authors:Shen, Fei1, 2 ; Wang, Qing1 ; Li, Yang1 ; Li, Xiujin2 ; Hu, Jinguang3
Author affiliation:1 College of Resources and Environment, Sichuan Agricultural University, Chengdu 611130, China
2 School of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
3 Faculty of Forestry, University of British Columbia, Vancouver V6T1Z4, Canada
Corresponding author:Shen, F. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:168-173
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to improve the performance of saccharification of Jerusalem artichoke stalk in bioethanol production, the hydrothermal pretreatment of stalk with H2SO3 catalysis and high-substrate consistency enzymatic hydrolysis were performed. Based on this work, the suitable pretreatment conditions, the high substrate consistency potential and the enzymes input lowering potential were determined. The results indicate that the suitable pretreatment should be carried out at 180°C with 2% H2SO3 catalysis, by which the hemicellulose in stalk could be completely removed. Consequently, the maximum hydrolysis ratio of 90.0% could be achieved with 2.0% substrate consistency, 20 FPU/g cellulose loading and 40 CBU/g cellobiase loading. The high substrate consistency potential of pretreated Jerusalem artichoke stalk was suggested as 12% for enzymatic hydrolysis. The cellulase and the cellobiase input at this consistency could be lowered to 15 FPU/g and 20 CBU/g, by which the hydrolysis ratio of 88.3% could be achieved, with only 1.8% decrease compared with the maximum hydrolysis ratio. Correspondingly, the cellulase and the cellobiase loading is reduced by 25% and 50%, respectively.
Number of references:23
Main heading:Loading
Controlled terms:Catalysis - Cellulose - Enzymatic hydrolysis - Saccharification - Substrates
Uncontrolled terms:Bio-ethanol production - High-substrate consistency - Hydrolysis ratio - Hydrothermal pretreatment - Jerusalem artichoke - Pre-Treatment - Pretreatment conditions
Classification code:461 Bioengineering and Biology - 672 Naval Vessels - 801 Chemistry - 802.2 Chemical Reactions - 815.1.1 Organic Polymers
DOI:10.6041/j.issn.1000-1298.2014.03.028
Database:Compendex
15. Accession number:20141717619087
Title:Orthogonal test and regression analysis for biogas production of shii-take cultivation waste
Authors:Deng, Yuanfang1 ; Qiu, Ling2
Author affiliation:1 Jiangsu Key Laboratory for Biomass-based Energy and Enzyme Technology, Huaiyin Normal University, Huaian 223300, China
2 College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Qiu, L. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:174-178
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Shii-take cultivation waste (SCW) was used as rich carbon material for anaerobic digestion under the mesospheric condition as (35±1)°C. Orthogonal test and regression analysis L9(33) were employed to determine the effects of the three factors including pretreatment period, inoculums concentration and total solids (TS) on biogas production. The optimal combination of the three factors has been achieved. The high-carbon content material was proved to be not an ideal feedstock for biogas production. However, after a certain period of pretreatment, the high carbon feedstock biogas production was improved a lot. The biogas production reached to 0.16 L/g(TS), increased by 128.57% compared with the control sample. The sequence of factors effecting SCW anaerobic fermentation is pretreatment period (evident), TS (evident), and inoculums concentration (less evident). A multiple regression equation was established and can be used for biogas production prediction under different conditions.
Number of references:18
Main heading:Biogas
Controlled terms:Anaerobic digestion - Carbon - Feedstocks - Regression analysis
Uncontrolled terms:Anaerobic fermentation - Biogas production - Carbon material - Control samples - Multiple regression analysis - Multiple regression equations - Optimal combination - Orthogonal test
Classification code:452.4 Industrial Wastes Treatment and Disposal - 522 Gas Fuels - 804 Chemical Products Generally - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2014.03.029
Database:Compendex
16. Accession number:20141717619111
Title:Flow self-measurement method for single chamber and single vibrator piezoelectric pump
Authors:Sun, Yeming1, 2 ; Zeng, Ping1 ; Cheng, Guangming1 ; Huang, Hecheng1
Author affiliation:1 College of Mechanical Science and Engineering, Jilin University, Changchun 130022, China
2 College of Mechanical Engineering, Northeast Dianli University, Jilin 132012, China
Corresponding author:Zeng, P. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:327-332
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Aiming at the accurate fluid control and the miniaturization of piezoelectric pump system, a flow self-measurement method for single chamber and single vibrator piezoelectric pump was proposed based on piezoelectric self-sensing and neural network. A bimorph vibrator was applied in piezoelectric pump acting as actuator and sensor simultaneously. Firstly, the influencing factors of flow were analyzed using the pi theorem of hydromechanics. Secondly, the relationship between sensing piezoelectric signal and deformation of the vibrator was studied. Then, the information of flow implicit in the sensing piezoelectric signal was found. Thus, a prototype of the parameter measurement circuit for sensing piezoelectric signal was made, and a BP neural network model for flow prediction was constructed by using the parameters acquired from the circuit as the input vector. Experimental results show that the correlation coefficient between the predicted data and the measured data is above 0.9993, and the maximum relative error is less than 3.46%. the results of prediction are close to the actual data. The method proposed for flow self-measurement has a good accuracy.
Number of references:17
Main heading:Piezoelectric devices
Controlled terms:Measurements - Neural networks - Piezoelectricity - Vibrators
Uncontrolled terms:BP neural network model - Correlation coefficient - Flow - Maximum relative errors - Parameter measurement - Piezoelectric pump - Piezoelectric signals - Self-sensing
Classification code:691.1 Materials Handling Equipment - 701.1 Electricity: Basic Concepts and Phenomena - 704 Electric Components and Equipment - 714 Electronic Components and Tubes - 723.4 Artificial Intelligence - 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.1000-1298.2014.03.053
Database:Compendex
17. Accession number:20141717619099
Title:Visual simulation of cucumber leaf color based on the relative content of chlorophyll
Authors:Lu, Shenglian1 ; Wang, Liping1, 2 ; He, Huojiao2 ; Guo, Xinyu1
Author affiliation:1 Beijing Research Center for Information Technology in Agriculture, Beijing 100097, China
2 School of Information and Engineering, Jiangxi Agricultural University, Nanchang 330045, China
Corresponding author:Guo, X. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:250-254 249
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A method for visual simulating leaf color based on the relative content of chlorophyll was proposed. The mathematical model between cucumber leaf color components and chlorophyll relative content was established according to images acquisited from real field and measuring chlorophyll relative content (SPAD) of the cucumber leaf in normal growth state continuously, and the model was also verified by using root-mean-square error (RMSE). The results showed that the RMSE between the observed values (R, G, B) and simulated vales(R, G, B) in leaf are 13.43%, 8.47%, 7.42% respectively. The rendering for the spatial distribution of apparent color of cucumber leaf was realized by combining with a black and white pigment distribution texture which was a grayscale image before being preprocessed. Then the high level shader language (OpenGL 2.0 Shader Language) was used to realize the rendering of apparent color changing process of cucumber leaf. The above process showed that the method proposed can achieve better realistic rendering results.
Number of references:21
Main heading:Color
Controlled terms:Application programming interfaces (API) - Chlorophyll - Mathematical models
Uncontrolled terms:Content of chlorophyll - Cucumber leaf - Gray-scale images - Leaf color - Realistic rendering - Root-mean-square errors - SPAD - Visual simulation
Classification code:723 Computer Software, Data Handling and Applications - 741.1 Light/Optics - 804.1 Organic Compounds - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.041
Database:Compendex
18. Accession number:20141717619098
Title:Label-free amperometic immunosensor for detection of brucella antibody
Authors:Yang, Wei1 ; Zuo, Yueming1 ; Wu, Haiyun2 ; Zhang, Zhiyong1 ; Zhang, Rong3 ; Chen, Chen1
Author affiliation:1 College of Engineering, Shanxi Agricultural University, Taigu 030801, China
2 Department of Electromechanical Engineering, Tianjin Agricultural University, Tianjin 300384, China
3 College of Horticulture, Shanxi Agricultural University, Taigu 030801, China
Corresponding author:Zuo, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:243-249
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to improve the detection sensitivity of brucella antibody and discover diseased livestock earlier for reducing economic losses, a disposable label-free immunosensor for rapid and quantitative detection was prepared. It was made by modification of cysteamine onto screen-printed gold electrode surface and immobilization of antigens. By the method of cyclic voltammetry, it was shown that there is a linear relationship between the changes of peak current and the different brucella antibody concentrations within the range of 10-5~10-3 IU/mL, the relevant correlation coefficient is 0.9999 and the lower detection limit is 2.8×10-5 IU/mL. Furthermore, semi-differential transformation was applied to all of the cyclic voltammograms, the correlation between the changes of semi-differential values and the corresponding concentration of brucella antibody has been established, the correlation coefficient is 0.9929 and the lower detection limit is 2.7×10-6 IU/mL in the range of 10-5~10-3 IU/mL, and the correlation coefficient is 0.9992 in the range of 10-2~1 IU/mL. It was shown that the detection range and the lower detection limit were improved greatly by the semi-differential transformation.
Number of references:30
Main heading:Chemical detection
Controlled terms:Agriculture - Antibodies - Cyclic voltammetry - Gold - Immunosensors - Losses
Uncontrolled terms:Antibody concentration - Brucella - Correlation coefficient - Detection sensitivity - Label-free immunosensor - Quantitative detection - Screen-printed gold electrode - Semi-differential
Classification code:461.9.1 Immunology - 547.1 Precious Metals - 801 Chemistry - 801.4.1 Electrochemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 911.2 Industrial Economics
DOI:10.6041/j.issn.1000-1298.2014.03.040
Database:Compendex
19. Accession number:20141717619088
Title:Numerical simulation of the effect of gas property on the performance of cyclone separator
Authors:Li, Kai1 ; Chen, Dengyu1 ; Zhu, Xifeng1
Author affiliation:1 Key Laboratory for Biomass Clean Energy of Anhui Province, University of Science and Technology of China, Hefei 230026, China
Corresponding author:Zhu, X. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:179-183 195
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The flow fields in cyclone at various model gases with ρ=0.6125~2.4500 kg/m3 and μ=4.4735×10-6~4.4735×10-5 kg/(m·s) were simulated by the computational fluid dynamics (CFD) software package, FLUENT 6.3. The influences of density and viscosity of gases on the dimensionless tangential velocity and pressure drop were performed respectively by single factor analysis. The result indicated that the dimensionless tangential velocity of gas flow in cyclone increases as the viscosity increase, while decreases with the increase of viscosity. Both density and viscosity have logarithmic function relations with the dimensionless maximum tangential velocity. The drag coefficient is not only influenced by the geometric parameters of the cyclone, but also affected by the viscosity of gases; there is a logarithmic regression between the pressure drop and viscosity of gas. Moreover, a fitting bivariate polynomial equation between the dimensionless tangential velocity and the factors was obtained.
Number of references:20
Main heading:Computational fluid dynamics
Controlled terms:Computer simulation - Cyclone separators - Density (specific gravity) - Polynomial approximation - Pressure drop - Storms - Viscosity - Viscosity of gases
Uncontrolled terms:Bivariate polynomial equations - Fluent 6.3 - Gas properties - Logarithmic functions - Performance - Simulation - Tangential velocities - Viscosity increase
Classification code:443.3 Precipitation - 723.5 Computer Applications - 802.1 Chemical Plants and Equipment - 921.6 Numerical Methods - 931.1 Mechanics - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.6041/j.issn.1000-1298.2014.03.030
Database:Compendex
20. Accession number:20141717619084
Title:Reconstruction of ploughed soil surface with 3D fractal interpolation
Authors:Liu, Yiguan1, 2 ; Lu, Zhixiong1 ; Hoogmoed, W.B.3 ; Li, Xiaoqin1
Author affiliation:1 College of Engineering, Nanjing Agricultural University, Nanjing 210031, China
2 Nanjing Communications Institute of Technology, Nanjing 211188, China
3 Farm Technology Group, Wageningen University and Research Centre, Wageningen 6700, Netherlands
Corresponding author:Lu, Z. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:152-157
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:By using a laser profiler, the roughness of ploughed soil surface was obtained. 3D fractal interpolation method was used to interpolate several kinds of reduced measured surface data which were reduced from the original measured ploughed soil surface elevation data in different reduction rates. Also fractal and statistical characteristic parameters were used to compare the original data and the interpolated data. The results show that 3D ploughed soil surface model can be obtained efficiently by the 3D fractal interpolation method with the reduction rate below 80% and the fractal non-scale spacing of the dimensions was deduced: the transverse and longitudinal spacing were 23 mm and 459 mm, respectively. The result provided a theory for choosing the minimum measurement spacing of the ploughed soil and a method for reconstruction of ploughed soil surface.
Number of references:18
Main heading:Data reduction
Controlled terms:Fractals - Interpolation - Soils - Surface reconstruction - Three dimensional
Uncontrolled terms:Fractal interpolation - Iterated function system - Laser profilers - Reduction rate - Soil roughness - Soil surfaces - Statistical characteristics - Surface data
Classification code:483.1 Soils and Soil Mechanics - 723.2 Data Processing and Image Processing - 723.5 Computer Applications - 921 Mathematics - 921.6 Numerical Methods
DOI:10.6041/j.issn.1000-1298.2014.03.026
Database:Compendex
21. Accession number:20141717619104
Title:Precision reverse design of numerical controlled (NC) machine on the basis of multibody theory
Authors:Xing, Yuan1 ; Zhang, Lianhong1 ; He, Baiyan1 ; Wang, Shuxin1
Author affiliation:1 Key Laboratory of Mechanism Theory and Equipment Design, Ministry of Education, Tianjin University, Tianjin 300072, China
Corresponding author:Zhang, L. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:282-287 304
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Usually machine geometry precision design is preformed depending on human experience but not reference data form design theory. To learn numerical effect an approximate model of relationship between machine geometry precision and product machining precision is provided based on multibody theory. The analysis results by Monte Carlo sampling would deduce geometry precision of each axis in machine. Taking geometry precision design of spiral bevel gear milling machine as an example, the approximate model well explains effect of machine geometry error on gear product surface machining quality by explicit. Then geometry precision of each axis is obtained by mapping from tooth surface machining precision.
Number of references:15
Main heading:Machine tools
Controlled terms:Design - Monte Carlo methods
Uncontrolled terms:Geometry precision - Machining precision - Multi-body - NC-machining - Reverse designs
Classification code:408 Structural Design - 603.1 Machine Tools, General - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2014.03.046
Database:Compendex
22. Accession number:20141717619077
Title:Modeling distributions of water and nitrate in soil as affected by drip system uniformity under arid conditions
Authors:Guan, Hongjie1 ; Li, Jiusheng1 ; Li, Yanfeng1
Author affiliation:1 State Key Laboratory of Simulation and Regulation of Water Cycle in River Basin, China Institute of Water Resources and Hydropower Research, Beijing 100038, China
Corresponding author:Li, J. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:107-117
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A model simulating the transport of water and nitrate in soil under mulched drip irrigation of cotton was established and solved numerically by using the HYDRUS-2D package. The model was calibrated and validated by the field experiments conducted in Urumqi, Xinjiang Uygur Autonomous Region, China, during the cotton growing seasons of 2010 and 2011. The emitter discharge rates that progressively decreased from the inlet to the distal end along the dripline were discretized as a series of sequential segments each having an equal discharge rate. Assuming no lateral exchange of water in soil between adjacent segments, the model, which had been verified, was used to evaluate the effect of drip system uniformity and soil spatial variability on the distributions of water and nitrate in soil under arid conditions. The results indicated that the uniformity coefficients of soil water content and nitrate were observed in downward trend for drip system uniformity coefficients (Cu) of 0.60 and 0.80, while a relatively stable variation pattern was observed for Cu=0.95; the lower system uniformity the greater decrease in the uniformity coefficient of soil water content and nitrate following an irrigation event was observed. The uniformity coefficient of soil nitrate, which varied from 0.35 to 1.00, was substantially lower than that of soil water content. Meanwhile, the soil spatial variability in the experimental field increased the nonuniform distributions of the soil water and nitrate.
Number of references:31
Main heading:Nitrates
Controlled terms:Cotton - Cultivation - Irrigation - Mathematical models - Soil moisture
Uncontrolled terms:Drip irrigation - Modeling distributions - Mulched drip irrigations - Non-uniform distribution - Soil water content - Spatial variability - Uniformity coefficient - Xinjiang Uygur autonomous region
Classification code:483.1 Soils and Soil Mechanics - 804.2 Inorganic Compounds - 821.3 Agricultural Methods - 821.4 Agricultural Products - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.019
Database:Compendex
23. Accession number:20141717619073
Title:Analysis of hydraulic performance of outlet passage based on simulation of steady flow in whole passage of axial-flow pumping system
Authors:Yang, Fan1, 2 ; Liu, Chao1, 2 ; Tang, Fangping2 ; Zhou, Jiren1, 2
Author affiliation:1 School of Hydraulic, Engineering and Power Engineering, Yangzhou University, Yangzhou 225127, China
2 Hydrodynamic Engineering Laboratory of Jiangsu Province, Yangzhou University, Yangzhou 225009, China
Corresponding author:Liu, C. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:83-89
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to investigate the influence of dividing pier on the hydraulic performance of a low-lift axial-flow pumping system, CFD method was used to simulate the three-dimensional internal flow of a low-lift pumping system with different outlet passages. The performance of the pumping system was estimated, and was compared with test data. Focusing on analyzing of the influence of dividing pier on the hydraulic performance of outlet passages and external characteristic of the pumping system, flows in two channels of the outlet passage are unequal to each other, the flow imbalance problem and the influence of velocity circulation on the hydraulic performance were analyzed as well. Results show that the dividing pier has great influence on the performance of the low-lift pumping system and should be avoided. Protrusive dividing pier makes the hydraulic loss of outlet passages increased and flow distribution more unequal. Backward extension of dividing pier does not influence the flow distribution, but makes hydraulic loss of outlet passage increase which induces degradation of the performance of the pumping system. Under the condition of zero velocity circulation, the hydraulic loss of outlet passage is in proportion to the square of flow, and the hydraulic loss is larger than that with velocity circulation and the flow is more complex. The internal and external performance of outlet passages has the relationship with the running condition of the pumping system, so it should avoid calculating the flow patterns of a separated outlet passage.
Number of references:12
Main heading:Pumping plants
Controlled terms:Computational fluid dynamics - Computer simulation - Piers
Uncontrolled terms:External characteristic - External performance - Flow distribution - Flow imbalances - Hydraulic performance - Passage - Pumping systems - Running conditions
Classification code:407.1 Maritime Structures - 446 Waterworks - 723.5 Computer Applications
DOI:10.6041/j.issn.1000-1298.2014.03.015
Database:Compendex
24. Accession number:20141717619110
Title:Numerical study on flow moment of 2D high frequency rotary valve
Authors:Bai, Jiping1, 2 ; Jia, Wen'ang1 ; Ruan, Jian1
Author affiliation:1 Key Laboratory of Mechanical Manufacture and Automation, Ministry of Education, Zhejiang University of Technology, Hangzhou 310014, China
2 Department of Maritime, Zhejiang Institute of Communications, Hangzhou 311112, China
Corresponding author:Ruan, J. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:320-326
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Two-dimensional high-frequency rotary valve is a kind of rotary valve designed by using spool with two degrees of freedom. When the spool rotates at a high speed, the velocity variation of fluid flowing through the valve ports generates periodic hydraulic torque on the spool, which imposes negative effects on the spool movement or even adversely affects the function of the valve. By calculating the flow fields in the chamber of 2D high-frequency rotary valve with different spool geometrical configurations, the influences of different geometrical dimensions on the average pressure and the average velocity around the notch walls and the flow moment imposed on the spool are presented. The results show that the structure and the layout of No.3 spool unit and No.4 are reasonable, and that the greater the spool groove bottom height h is, the more smoothly the hydraulic moment changes and the greater the flow rate through the valve port is.
Number of references:17
Main heading:Reels
Controlled terms:Two dimensional - Valves (mechanical)
Uncontrolled terms:Average velocity - Geometrical configurations - Geometrical dimensions - High frequency HF - Hydraulic moments - Rotary valves - Two degrees of freedom - Velocity variations
Classification code:601.2 Machine Components - 742.2 Photographic Equipment - 902.1 Engineering Graphics
DOI:10.6041/j.issn.1000-1298.2014.03.052
Database:Compendex
25. Accession number:20141717619108
Title:Creeping mechanism and suppression methods of hydraulic cylinder under nonlinear time-varying force
Authors:Zhu, Yong1 ; Jiang, Wanlu1 ; Wang, Meng2 ; Liu, Zhiqiang2
Author affiliation:1 Hebei Provincial Key Laboratory of Heavy Machinery Fluid Power Transmission and Control, Yanshan University, Qinhuangdao 066004, China
2 Key Laboratory of Advanced Forging and Stamping Technology and Science, Ministry of Education, Yanshan University, Qinhuangdao 066004, China
Corresponding author:Jiang, W. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:305-313
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The aim of this research is to explore the mechanism and the suppression methods of creeping phenomenon in hydraulic cylinder system. The nonlinear time-varying laws and function mechanism of hydraulic spring stiffness and friction were revealed through theory analysis. Then, with the nonlinear dynamics methods, the measured dynamic data were thoroughly analyzed. The "jump phenomenon" caused by the nonlinear time-varying characteristic of hydraulic spring stiffness and the "limit cycle oscillation" caused by the nonlinear time-varying characteristic of friction were revealed. The combined effect of nonlinear hydraulic spring force and nonlinear friction is the main cause for the low-speed creeping of hydraulic cylinder. Moreover, the corresponding suppression measures were proposed to improve the low-speed transmission stability of hydraulic cylinder. The results indicate that the research can make the comprehensive analysis of dynamic characteristics of hydraulic cylinder system more realistic.
Number of references:16
Main heading:Mechanical actuators
Controlled terms:Friction - Stiffness - Tribology
Uncontrolled terms:Dynamic characteristics - Hydraulic cylinders - Limit Cycle Oscillation (LCO) - Low-speed creeping - Mechanism analysis - Nonlinear dynamics method - Suppression measures - Time-varying characteristics
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 732.1 Control Equipment - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 951 Materials Science
DOI:10.6041/j.issn.1000-1298.2014.03.050
Database:Compendex
26. Accession number:20141717619061
Title:Steering system design of Hilly power chassis with balance rocker suspension
Authors:Gao, Qiaoming1 ; Gao, Feng1 ; Lai, Yongyu2 ; Xu, Guoyan1 ; Ding, Nenggen1
Author affiliation:1 School of Transportation Science and Engineering, Beihang University, Beijing 100191, China
2 Guangxi Zhuang Autonomous Region Agricultural Machinery Appraisal Station, Nanning 530001, China
Corresponding author:Gao, F. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:13-19
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A kind of Hilly power chassis with variable ground clearance and wheel track (VII-HPC) was designed to adapt to hilly terrain and agronomic characteristics of various types of crops. Hydraulic four wheel steering scheme without steering trapezoid has been proposed. To reduce turning radius and achieve same rut steering, the steering strategies are two ipsilateral wheels steering with a reverse and equal angle. The displacement relationship of right and left steering cylinder would be optimized by genetic algorithm to achieve Ackermann steering. The rotation of the steering wheel is not too large to avoid movement interference, which the minimum turning radius of the same wheelbase ordinary tractor was provided a reference. After change ground clearance, the wheel deflected around the kingpin. The relationship between the effective turning angle in the horizontal plane and the displacement of cylinder should be redefined according to the geometric relation. The conditions to meet the Ackermann steering need to be re-discussed because the wheelbase and track of the chassis would be altered after VII-HPC change ground clearance and the track. Experimental results show that the structure of steering system and steering strategy is reasonable and feasible.
Number of references:15
Main heading:Chassis
Controlled terms:Cylinders (shapes) - Wheels
Uncontrolled terms:Ackermann steering - Geometric relations - Ground clearance - Hilly areas - Movement interference - Rocker suspension - Steering systems - Turning angles
Classification code:408.2 Structural Members and Shapes - 601.2 Machine Components - 663.2 Heavy Duty Motor Vehicle Components
DOI:10.6041/j.issn.1000-1298.2014.03.003
Database:Compendex
27. Accession number:20141717619083
Title:Adaptability of near-infrared sensor for moisture measurement of different soils
Authors:Yin, Zhe1 ; Lei, Tingwu1 ; Chen, Zhanpeng1 ; Yan, Qinghong1 ; Dong, Yuequn1
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Lei, T. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:148-151 190
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The sensor for soil moisture measurement should have broad adaptability, and the soil moisture can be measured by the sensor upon the determination of the relationship between soil moisture and relevant variable. Five typical soils from different geographic locations of China were sampled for soil moisture measurement test with the near infrared sensor designed with 1940 nm as measuring wavelength and 1800 nm as reference wavelength. The reflectance of those two wavelengths was transformed to relative absorbance depth to minimize the influencing factors. The results indicate there existing strong linear correlation between soil moisture and relative absorption depth for different soils. Independent data sets were used to validate the calibration model, and the root mean square error is less than 6% except for the red soil from southern China. The research shows the adaptability of the sensor for different soils and the calibration steps.
Number of references:16
Main heading:Soil moisture
Controlled terms:Calibration - Infrared detectors - Mean square error - Moisture determination - Moisture meters - Sensors
Uncontrolled terms:Geographic location - Moisture Measurement - Near Infrared - Near-infrared sensors - Reference wavelengths - Relative absorptions - Root mean square errors - Soil moisture measurement
Classification code:483.1 Soils and Soil Mechanics - 731.1 Control 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.1000-1298.2014.03.025
Database:Compendex
28. Accession number:20141717619091
Title:Performance analysis of a biogas combined cooling heating and power system
Authors:Wang, Jiangjiang1 ; Yang, Kun1 ; Liu, Juanjuan1
Author affiliation:1 School of Energy, Power and Mechanical Engineering, North China Electric Power University, Baoding 071003, China
Corresponding author:Wang, J. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:196-205
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to improve energy efficiency and to relieve shortage of fossil energy and environmental problems, a biogas combined cooling heating and power (CCHP) system driven by internal-combustion engine was designed, and its energy flow was presented. As a case study, the biogas CCHP system for a hotel in Beijing, about 10000 m2, was analyzed and compared in two operation modes: following the electrical loads (FEL) and following the thermal loads (FTL). The equipment configuration, fuel consumption and supplementary power and the energy, economic and emission performances were calculated and compared in the two operation modes. The results indicate that the primary energy rate (PER) of the CCHP system in FEL is 4.3% higher than in FTL; the investment payback period is 1.4 years shorter; and the CO2 emission reduction is 254.9 t less. The biogas CCHP system in FTL has more environmental benefit and in FEL is more efficient and economical.
Number of references:36
Main heading:Biogas
Controlled terms:Carbon dioxide - Cooling - Electric loads - Emission control - Energy efficiency - Investments - Thermal load
Uncontrolled terms:Combined cooling heating and power - Electrical load - Emission performance - Environmental benefits - Environmental problems - Equipment configuration - Following the thermal loads - Performance comparison
Classification code:451.2 Air Pollution Control - 522 Gas Fuels - 525.2 Energy Conservation - 641.2 Heat Transfer - 643.1 Space Heating - 706.1 Electric Power Systems - 804.2 Inorganic Compounds - 911.2 Industrial Economics
DOI:10.6041/j.issn.1000-1298.2014.03.033
Database:Compendex
29. Accession number:20141717619090
Title:Numerical simulation and optimization on combustion of wood briquette heating stove
Authors:Jiang, Shaojian1 ; Wang, Tao2 ; Ai, Yuanfang1 ; Sun, Yanwen1 ; Peng, Haoyi1
Author affiliation:1 School of Energy Science and Engineering, Central South University, Changsha 410083, China
2 China Chengda Engineering Co. Ltd., Chengdu 610041, China
Corresponding author:Jiang, S. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:191-195
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The technology of swirling combustion and a new kind of wood briquette fuel swirling burner were proposed to improve thermal efficiency and reduce pollution emissions of the wood briquette heating stove. Numerical simulation on combustion processing of different excess air coefficient and different inclination between the secondary air inlet and grate wall in the heating stove was considered, aiming to solve the velocity, temperature and concentration field. The results reveal that high temperature backflow zone coming out through rotational flow secondary wind effectively strengthened combustion and improved the furnace using area; combustion efficiency is the highest and pollution is the lowest, when excess air coefficient is 1.5 and inclination angle is 30°.
Number of references:16
Main heading:Briquets
Controlled terms:Air - Combustion - Computer simulation - Heating - Numerical models - Optimization - Pollution - Ramjet engines - Stoves - Wood
Uncontrolled terms:Combustion efficiencies - Concentration fields - Excess air coefficient - Heating stoves - Pollution emissions - Secondary air inlet - Simulation and optimization - Swirling combustion
Classification code:454.2 Environmental Impact and Protection - 521.1 Fuel Combustion - 524 Solid Fuels - 642.2 Industrial Furnaces and Components - 643.1 Space Heating - 653.1 Aircraft Engines, General - 723.5 Computer Applications - 804 Chemical Products Generally - 811.2 Wood and Wood Products - 921 Mathematics - 921.5 Optimization Techniques
DOI:10.6041/j.issn.1000-1298.2014.03.032
Database:Compendex
30. Accession number:20141717619065
Title:Numerical calculation of cavitation flow in a centrifugal pump
Authors:Wang, Weijun1 ; Wang, Yang1 ; Liu, Ruihua2 ; Li, Yibin3 ; Yin, Gang1 ; Li, Guidong1
Author affiliation:1 Research Center of Fluid Machinery Engine and Technology, Jiangsu University, Zhenjiang 212013, China
2 China Energy Engineering Group Co. Ltd., Zhenjiang 212013, China
3 School of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou 730010, China
Corresponding author:Wang, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:37-44
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The paper aims to deal with the numerical simulation of cavitation phenomena inside the centrifugal pump and analyze the development of cavitation based on improved cavitation model, Standard k-Ε and RNG k-Ε turbulence model. When cavitation flow and non-cavitation flow were simulated and analyzed, the pressure of blades under incipient cavitation, developed cavitation and serious cavitation were gotten. The paper also gave the principle of incipient cavitation and divided the region into five cavitation regions based on bubble relative length. The results show that with the decreasing of inlet total pressure, bubble appears firstly in suction surface of the blade, and then moves along the blade profile, and next forms attached cavitation bubble. After this stage, bubble is gradually out of the mainstream movement and close to the pressure surface. Finally, the flow passage is filled with bubble, which hinders the flow. The number σ=0.3067 of incipient cavitation is a greater dimension hierarchy than that of σ=0.0281 under design condition. Seen from the impeller meridian plane, bubble appears firstly in the near the hub, goes towards forward cover plate, and attaches near the front cover. Cavitation in centrifugal pump is subdivided again into the five stages, that are incipient cavitation, critical cavitation, developing cavitation, complete cavitation, broken cavitation.
Number of references:17
Main heading:Cavitation
Controlled terms:Centrifugal pumps - Computer simulation - Multiphase flow - Numerical models - Turbulence models
Uncontrolled terms:Cavitation bubble - Cavitation model - Design condition - Dimension hierarchies - Impeller meridian - Incipient cavitation - Numerical calculation - Suction surfaces
Classification code:618.2 Pumps - 631.1 Fluid Flow, General - 631.1.1 Liquid Dynamics - 723.5 Computer Applications - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.007
Database:Compendex
31. Accession number:20141717619109
Title:Simple method for forward displacement analysis of a 5-5 in-parallel robot
Authors:Shi, Zhixin1 ; Ye, Meiyan2 ; Mao, Zhiwei1 ; Luo, Yufeng1 ; Yang, Tingli3
Author affiliation:1 Department of Mechanical and Electronic Engineering, Nanchang University, Nanchang 330031, China
2 Department of Science, Nanchang University, Nanchang 330031, China
3 Jinling Petrochemical Corporation, Nanjing 210037, China
Corresponding author:Shi, Z. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:314-319
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A simple method for forward displacement analysis of a kind of 5-5 in-parallel robot is presented, after its structural characteristic has been disclosed. First of all, the parallel robot was decomposed into three single-opened chains (SOCs). Secondly, the dimension of its kinematic equations was reduced to the minimum by considering kinematic model of the three single-opened chains. Then, all the real solutions to the kinematic equations were obtained using one-dimension searching algorithm. At last, a numerical example with 20 real solutions was given for the first time and provided to confirm the efficiency of the solution procedure.
Number of references:16
Main heading:Robots
Controlled terms:Chains - Kinematics
Uncontrolled terms:Forward displacement analysis - Forward displacements - Kinematic equations - One-Dimension - Parallel robots - Searching algorithms - Spatial mechanism - Structural characteristics
Classification code:602.1 Mechanical Drives - 731.5 Robotics - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2014.03.051
Database:Compendex
32. Accession number:20141717619067
Title:Numerical calculation and analysis of inner unsteady flow for volute centrifugal pump
Authors:Shi, Weidong1 ; Xu, Lei1 ; Wang, Chuan1 ; Lu, Weigang1 ; Zhou, Ling1
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Shi, W. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:49-53 60
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to study the flow characteristics in centrifugal pump at design condition, the inner unsteady flow was simulated based on high-quality structured grid and rapid prototyping technology by using the commercial software CFX. The results indicate that the method of unsteady numerical simulation can accurately predict the performance parameters of the centrifugal pump with the test. The maximum deviation of head and efficiency are less than 4% and 3%, respectively. Impacted by the impeller-volute coupling, the pressure pulsation in volute centrifugal pump has strong periodicity, and the basic frequency is the blade passing frequency. There is a similar pressure field between the impeller passage inlet and the middle of impeller passage, but the pressure distribution near the impeller outlet has a significant difference. Significant secondary flow phenomena exist in the volute and move forward with the mainstream.
Number of references:17
Main heading:Centrifugal pumps
Controlled terms:Computer simulation - Impellers - Unsteady flow
Uncontrolled terms:Blade passing frequency - Flow charac-teristics - Flow field distribution - Performance parameters - Performance prediction - Pressure fluctuation - Rapid prototyping technology - Unsteady numerical simulations
Classification code:601.2 Machine Components - 618.2 Pumps - 631.1 Fluid Flow, General - 723.5 Computer Applications
DOI:10.6041/j.issn.1000-1298.2014.03.009
Database:Compendex
33. Accession number:20141717619068
Title:Numerical simulation and testing analysis of three dimensional turbulence flow in flow-ejecting self-priming centrifugal pump
Authors:Wang, Weijun1 ; Wang, Yang1 ; Li, Guidong1 ; Yin, Gang1 ; Cao, Puyu1
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Wang, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:54-60
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to gain the inner flow field of flow-ejecting self-priming centrifugal pump, a flow-ejecting self-priming centrifugal pump equipped with a jet in the front of impeller inlet was chosen as the study object. The geometric model including all parts was built up by Pro/E software. The turbulence model chosen was RNG k-Ε turbulence model and the mesh independence was checked by six meshes with different grid number. The external performances and the inner flow fields under seven different working conditions were simulated by CFX 14.0. The profiles, such as static pressure and velocity, were obtained. Then, the numerical results were compared with the testing results gotten on open test bed. The results show that the errors of head, shift power and efficiency between the simulation and the testing under designed condition are 2.63%, 6.16% and 14.29%, respectively. The simulating and the testing power curves are almost horizontal lines and change slowly when the flow rate is smaller than 3.5 m3/h. The absolute velocity distribution between the nozzle and the line segment is axial symmetry. However, between the diffusion section and the impeller inlet, the upper velocity is larger than the lower velocity. And the velocity of the flow entering the impeller inlets is not uniform. The location, L=0.148 m, is a critical location where the static pressure is the smallest and the turbulence dissipation rate achieves its maximum value. The numerical results provide a directly theoretical guideline for the pump design.
Number of references:16
Main heading:Inlet flow
Controlled terms:Centrifugal pumps - Computer simulation - Equipment testing - Flow fields - Impellers - Numerical models - Turbulence models - Velocity - Velocity distribution
Uncontrolled terms:Designed conditions - External performance - Geometric modeling - Performance prediction - Self-priming centrifugal pumps - Simulation and testing - Three-dimensional turbulence - Turbulence dissipation rate
Classification code:601.2 Machine Components - 618.2 Pumps - 631.1 Fluid Flow, General - 723.5 Computer Applications - 921 Mathematics - 931.1 Mechanics - 931.3 Atomic and Molecular Physics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 943.2 Mechanical Variables Measurements - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.6041/j.issn.1000-1298.2014.03.010
Database:Compendex
34. Accession number:20141717619078
Title:Variation of soil moisture under different rainwater harvesting and conservation practices in the western part of Loess Plateau
Authors:Li, Xiaoying1 ; Duan, Zhenghu1 ; Liu, Lichen2 ; Tan, Mingliang1 ; Chen, Xiaohong1
Author affiliation:1 Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China
2 College of Resource and Environmental Sciences, Lanzhou University, Lanzhou 730000, China
Corresponding author:Li, X. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:118-123
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The ecological restoration area in the west part hill area of the Loess Plateau was chosen for the object in this work. Neutron probe was used to test the moisture change in Pinus tabulaeformis forest soil under different rainwater harvesting and water conservation measures. The dynamic characteristics of soil moisture under different rainwater harvesting and water conservation measures, the deficit and compensation of soil moisture before and after rainy season were analyzed. Results show that soil moisture storage capacity under different rainwater harvesting and water conservation measures is significant different. The soil moisture under slope water-harvesting measure is greater than those with other measures. The soil water storage deficit is alleviated under seven measures in July. Soil water storage deficit from 0~100 cm is alleviated under slope water-harvesting and slope water-harvesting with water harvesting groove reversed. Results of this study indicate that slope water-harvesting has a significant effect on the effective use of precipitation. Film mulches mulch has a negative impact on the recovery of the surface soil moisture, but has an obvious effect on water conservation of deep soil moisture. Wallow-tail type runoff collecting pit is ineffective in increasing the efficiency of precipitation use and compensation of soil water storage deficit.
Number of references:15
Main heading:Rain
Controlled terms:Collector efficiency - Harvesting - Landforms - Soil moisture - Water conservation
Uncontrolled terms:Conservation practices - Dynamic characteristics - Ecological restoration - Loess Plateau - Moisture storage capacity - Pinus tabulaeformis forest - Soil water deficit - Soil-water conservation
Classification code:443.3 Precipitation - 444 Water Resources - 481.1 Geology - 483.1 Soils and Soil Mechanics - 702.3 Solar Cells - 821.3 Agricultural Methods
DOI:10.6041/j.issn.1000-1298.2014.03.020
Database:Compendex
35. Accession number:20141717619075
Title:Sample spacing of spatial variability of soil hydraulic parameters in basin scale based on GPS and Google Earth
Authors:Wang, Weihua1 ; Wang, Quanjiu2, 3
Author affiliation:1 Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming 650500, China
2 Institute of Water Resources and Hydro-electril Engineering, Xi'an University of Technology, Xi'an 710048, China
3 State Key Lab. of Soil Erosion and Dryland Farm on Loess Plateau, Institute of Soil and Water Conservation, CAS and MWR, Yangling, Shaanxi 712100, China
Corresponding author:Wang, Q. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:97-100 106
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:There are some problems, such as how to use advanced methods, how to make less work, economical and reasonable experimental design and how to make representative sampling points during soil analysis. The above-mentioned problems are becoming research difficulties and hotspots in recent years. A research on spatial variability of soil hydraulic parameters basin scale in Jinghui Irrigation, Shaanxi Province was made based on GPS and Google Earth methods. The results showed that saturated soil moisture content and saturated hydraulic conductivity moderate variation in the regional scale show out moderate variability and strong spatial dependence. The best-fitting models for saturated soil moisture content and saturated hydraulic conductivity are spherical model and exponential model, respectively. As for the above two, the sample spacing of 2.38 km and 7.14 km are recommended.
Number of references:22
Main heading:Hydraulic conductivity
Controlled terms:Design - Global positioning system - Moisture determination - Soil moisture
Uncontrolled terms:Basin scale - Exponential models - Google earths - Representative sampling - Saturated hydraulic conductivity - Soil hydraulic parameters - Spatial dependence - Spatial variability
Classification code:408 Structural Design - 483.1 Soils and Soil Mechanics - 632.1 Hydraulics - 716.3 Radio Systems and Equipment - 944.2 Moisture Measurements
DOI:10.6041/j.issn.1000-1298.2014.03.017
Database:Compendex
36. Accession number:20141717619106
Title:Modeling and closed-loop control in workspace of parallel optoelectronic tracking platform
Authors:Li, Kexiang1 ; Zhang, He1
Author affiliation:1 Ministerial Key Laboratory of ZNDY, Nanjing University of Science and Technology, Nanjing 210094, China
Corresponding author:Zhang, H. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:293-298
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to meet the optoelectronic tracking requirements for a small size floating stabilized platform with small volume and high load inertia, an improved parallel mechanism based on deficient DOF parallel mechanism has been designed. The Jacobian matrix is derived, and the dynamic model has been established by using Lagrange method. Considering the internal coupling, uncertainties and disturbances of the system, a workspace based composite control with disturbance observer is proposed. The disturbance observer is used to observe the disturbance of the system and reduces the upper bound of the disturbance. Based on backstepping method, the sliding mode controller is designed for tracking and residual disturbance suppression. The simulation and experiment results show that the proposed model and method have made tracking error reduced to ±0.08° which is 14.5% of PID, and is suitable for parallel mechanism.
Number of references:15
Main heading:Mechanisms
Controlled terms:Backstepping - Computer simulation - Dynamic models - Jacobian matrices - Sliding mode control
Uncontrolled terms:Back-stepping method - Disturbance observer - Disturbance suppression - Opto-electronic tracking - Parallel mechanisms - Sliding mode controller - Stabilized platform - Workspace
Classification code:601.3 Mechanisms - 723.5 Computer Applications - 731.1 Control Systems - 921 Mathematics - 921.1 Algebra
DOI:10.6041/j.issn.1000-1298.2014.03.048
Database:Compendex
37. Accession number:20141717619060
Title:Direct torque control of sensorless AC electric power steering system
Authors:Zheng, Taixiong1 ; Zhou, Hua1 ; Gu, Hongming1
Author affiliation:1 Engineering Research Center of Automotive Electronic and Embedded System, Chongqing University of Posts and Telecommunications, Chongqing 400065, China
Corresponding author:Zheng, T. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:7-12
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Electric power steering (EPS) system driven by permanent magnet synchronous motor (PMSM) has become the future trend of development. In order to adapt the characteristics of AC motor, dynamical-returnability characteristics based on fuzzy rules were designed. The extended Kalman filter (EKF) was introduced to estimate the stator flux and location, and the direct torque control (DTC) was adopted to control PMSM, so as to accelerate the response rate and precision. Referring to the national standard, simulation of this system was carried out on steering portability and return performance, the results show that the effect of the proposed system is significant under PMSM assisting, the steering wheel average operating torque is reduced by 45%, and the wheel self-turning time shortens 50%. Finally the bench test was experimented and shows that the whole system dynamic operates well and can fully complete the power control target.
Number of references:15
Main heading:Permanent magnets
Controlled terms:AC generator motors - Extended Kalman filters - Synchronous motors - Wheels
Uncontrolled terms:Control target - Direct torque control - Electric power steering - Electric power steering system - National standard - Permanent Magnet Synchronous Motor - Steering wheel - System Dynamics
Classification code:601.2 Machine Components - 704.1 Electric Components - 705.3.1 AC Motors - 731.1 Control Systems
DOI:10.6041/j.issn.1000-1298.2014.03.002
Database:Compendex
38. Accession number:20141717619096
Title:Fast detection of heavy metal lead (Pb) in vetiver grass leaves using near infrared spectroscopy
Authors:Liu, Yande1 ; Shi, Yu1
Author affiliation:1 School of Mechatronical and Electronical Engineering, East China Jiaotong University, Nanchang 330013, China
Corresponding author:Liu, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:232-236
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Heavy mental ionsin plants always have complex chelation with the organic molecular groups that have the near-infrared spectral (NIRS) absorptions. Therefore heavy mental ions in plants can be indirectly detected by using INRS technique basing on the chelation. An application of near infrared spectral technology fast detecting heavy metal lead (Pb) in vetiver grass leaves was analyzed. Combined with partial least squares (PLS), different preprocessing methods including smoothness, standard normal variate, baseline correction, multiplicative scatter correction, first derivative and second derivative were compared, model parameters were optimized by different wavelength selection methods including genetic algorithm, interval partial least square and successive projections algorithm, established the fast detection models of heavy metal Pb in vetiver grass leaves. The results showed that the external validation determination coefficient (R2) and root mean square error of prediction (RMSEP) was 0.87 and 0.18 separately. The study shows that the fast detection of heavy metal Pb in vetiver grass leaves using INRS technique is feasible.
Number of references:15
Main heading:Chemical detection
Controlled terms:Chelation - Heavy metals - Infrared devices - Lead - Lead compounds - Least squares approximations - Mean square error - Near infrared spectroscopy - Plants (botany) - Principal component analysis
Uncontrolled terms:Determination coefficients - Interval partial least squares - Multiplicative scatter correction - Near infrared spectra - Quantitative detection - Root-mean-square error of predictions - Successive projections algorithm - Vetiver grass
Classification code:461.9 Biology - 531 Metallurgy and Metallography - 546.1 Lead and Alloys - 741.3 Optical Devices and Systems - 801 Chemistry - 802.2 Chemical Reactions - 804.1 Organic Compounds - 921.6 Numerical Methods - 922.2 Mathematical Statistics
DOI:10.6041/j.issn.1000-1298.2014.03.038
Database:Compendex
39. Accession number:20141717619069
Title:Analysis of the vortex-elimination device of pump suction passage using high-speed photography
Authors:Liu, Chao1 ; Yang, Fan1 ; Zhao, Jun2
Author affiliation:1 School of Hydraulic, Energy and Power Engineering, Yangzhou University, Yangzhou 225127, China
2 Anhui Anzhao Engineering Technical Advisory Services Limited Company, Bengbu 233000, China
Corresponding author:Liu, C. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:61-65
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to solve the problem of bottom-vortex in the cube type suction passage of pump 4 types of vortex-elimination devices were designed based on the vortex tubes intensity conservation theorem. To verify the validity of these devices, the test-rig was set up for experiment and the high-speed photography was applied to the flow pattern of the suction passage with different types of vortex-elimination devices. The bottom vortices in the original passage were captured successfully under different operation conditions. The effects of 4 new vortex-elimination devices on the hydraulic performance of pump system were analyzed based on the energy test. The results show that the new vortex-elimination device can eliminate the bottom vortex, the flow pattern of flare and the hydraulic performance of pump system can be improved.
Number of references:15
Main heading:Vortex flow
Controlled terms:Flow patterns - High speed photography - Pumps - Testing
Uncontrolled terms:Conservation theorem - Hydraulic performance - Operation conditions - Passage - Pump suction - Pump system - Suction passage
Classification code:423.2 Non Mechanical Properties of Building Materials: Test Methods - 618.2 Pumps - 631.1 Fluid Flow, General - 742.1 Photography
DOI:10.6041/j.issn.1000-1298.2014.03.011
Database:Compendex
40. Accession number:20141717619070
Title:Test comparative study on impact of different revolving speed on pressure fluctuation in axial flow pump
Authors:Shi, Weidong1 ; Yao, Jie1, 2 ; Zhang, Desheng1 ; Wu, Suqing1 ; Wang, Haiyu1
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
2 Patent Examination Cooperation Jiangsu Center of the Patent Office, SIPO, Suzhou 215000, China
Corresponding author:Shi, W. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:66-71
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Pressure fluctuation measurement was conducted on the key points in an axial flow pump operating at 1450 r/min, 1200 r/min, 1000 r/min, respectively based on test. According to amplitude analysis, the results showed that the RMS tends to decrease firstly and then increase with the increase of flow rate at the impeller inlet, and decline in outlet of impeller and outlet of vane. The RMS varies more quickly with higher revolving speed. In terms of frequency domain, the base frequency at three revolving speeds is blade frequency at the impeller inlet, at the same time there also exists such frequency components: Fn, 2Fn, 3Fn at revolving speeds of 1450 r/min and 1200 r/min. And at the impeller outlet, frequency domain ranges from 0 to 8Fn; the base frequency appears in the range of 3Fn to 4Fn at revolving speeds 1450 r/min and 1200 r/min and shifts to higher frequency from 4Fn to 6Fn at revolving speed of 1000 r/min. While at the outlet of guide-vanes, frequency domain of pressure fluctuation ranges from 0 to 12Fn; the base frequency appears in the range of 4Fn to 6Fn at revolving speed of 1450 r/min and 1200 r/min, and turns into another range from 6Fn to 8Fn at revolving speed of 1000 r/min. The pressure fluctuation law was obtained with different revolving speeds and measuring points in the axial flow pump actual operation in the study, which provides reference for numerical simulation and lays a theoretical basis for weakening pressure fluctuation of the axial flow pump.
Number of references:11
Main heading:Speed
Controlled terms:Axial flow - Experiments - Frequency domain analysis - Impellers
Uncontrolled terms:Amplitude characteristics - Axial flow pump - Comparative studies - Frequency components - Higher frequencies - Pressure fluctuation - Pressure fluctuation measurements - Spectral characteristics
Classification code:601.2 Machine Components - 631.1 Fluid Flow, General - 731.1 Control Systems - 901.3 Engineering Research - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2014.03.012
Database:Compendex
41. Accession number:20141717619081
Title:Effect of super absorbent polymer and irrigation on improving water use efficiency of arabica coffee seedling
Authors:Liu, Xiaogang1 ; Geng, Hongzhuo1 ; Cheng, Jinhuan2 ; Yang, Qiliang1 ; Shi, Weisheng1 ; Yang, Xinrong1
Author affiliation:1 Faculty of Modern Agricultural Engineering, Kunming University of Science and Technology, Kunming 650500, China
2 Tropical and Subtropical Economic Crops Institute, Yunnan Academy of Agricultural Sciences, Baoshan 678025, China
Corresponding author:Liu, X. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:134-139
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The object was to explore the efficient water-saving method of arabica coffee seedling, experiment of three levels of super absorbent polymer (SAP), i.e. high SAP (SH), low SAP (SL) and no SAP (SN), and three levels of irrigation, i.e. high water (WH), middle water (WM) and low water (WL), was designed, and the effect of SAP and irrigation on physiology, growth, dry mass accumulation and water consumption of arabica coffee seedling was studied. Results showed that, compared with SN, SL increases chlorophyll (Chl), carotenoid and root activity by 11.8%, 13.4% and 52.2%, but reduces soluble sugar (SS), malondialdehyde (MDA) and proline(Pro) by 24.9%, 24.3% and 55.8%, and also increases total dry mass and water use efficiency (WUE) by 31.0% and 35.9%, respectively; however, SH reduces Chl, carotenoid, MDA and root activity by 3.1%, 2.4%, 13.5% and 6.3%, and reduces total dry mass by 21.3% as well, but increases SS, MDA and WUE by 3.7%, 75.1% and 8.6%. Compared to WL, WM increases total dry mass, water consumption and WUE by 89.8%, 44.5% and 33.2%, while WH increases total dry mass, water consumption and WUE by 172.8%, 104.8% and 34.0%. Compared to CK (SNWL), SLWM has the largest increase of WUE by 112.7%, and increases total dry mass by 158.9%, as well as leaf relative water content, Chl, carotenoid and root activity by 24.4%, 19.5%, 25.8% and 149.9%, whereas reduces SS, MDA and Pro by 38.3%, 36.4% and 68.7%. Considering high efficiency water saving, SLWM is the optimum experiment combination.
Number of references:29
Main heading:Water supply
Controlled terms:Absorption - Efficiency - Experiments - Irrigation - Pigments - Plants (botany) - Polymers - Water conservation
Uncontrolled terms:Leaf relative water contents - Malondialdehyde - Physicochemical property - Root activities - Superabsorbent polymer - Water - savings - Water consumption - Water use efficiency
Classification code:444 Water Resources - 446.1 Water Supply Systems - 461.9 Biology - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 815.1 Polymeric Materials - 821.3 Agricultural Methods - 901.3 Engineering Research - 913.1 Production Engineering - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.6041/j.issn.1000-1298.2014.03.023
Database:Compendex
42. Accession number:20141717619071
Title:Numerical simulation of tip leakage vortex hydrodynamics characteristics in axial flow pump
Authors:Zhang, Desheng1 ; Shao, Peipei1 ; Shi, Weidong1 ; Pan, Dazhi1 ; Wang, Haiyu1
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Zhang, D. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:72-76 82
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The scaled model pump of TJ04-ZL-02 hydraulic model, which has been applied on the Tianjin same test-bed for South-to-North Water Transfer Project, was simulated base on fine calculation for tip region flow field and SST k-ω turbulence model, and flow field structure for tip leakage vortex as well as filed dynamic characteristics were studied. Numerical calculations and experimental results show that numerical simulations for clearance leakage and boundary layer flow based on SST k-ω turbulence model are relatively accurate. The power arose from tip leakage vortex is regard as differential pressure between the pressure side and the suction side of blade. For the pressure difference of blade leading edge is the largest, velocity of tip leakage flow is higher. The pressure difference between blade pressure and suction side is increased gradually with the increase of blade chord coefficient λ, and clearance leakage flow velocity as well as leakage vortex strength is decreased gradually. The local low pressure of blade tip region mainly occurs on vortex region of separated vortex near the pressure surface, as well as tip leakage vortex region at the lower part of blade suction side. The local low pressure region of blade suction side is getting further away from blade suction side with the increase of blade chord coefficient λ. The local low pressure region of blade rim near blade pressure side is mainly caused by separated vortex which is induced by blade tip corner, and the low pressure near suction side of blade is resulted from tip leakage vortex, and the process reveals the flow characteristic of tip leakage vortex for axial flow pump.
Number of references:15
Main heading:Computer simulation
Controlled terms:Axial flow - Boundary layer flow - Flow fields - Hydraulic models - Leakage (fluid) - Numerical models - Pumps - Turbulence models - Vortex flow
Uncontrolled terms:Axial flow pump - Differential pressures - Dynamic characteristics - Flow charac-teristics - Hydrodynamics characteristics - South to North Water Transfer Project - Tip clearance - Tip leakage vortex
Classification code:452.3 Industrial Wastes - 618.2 Pumps - 631.1 Fluid Flow, General - 632.1 Hydraulics - 723.5 Computer Applications - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.013
Database:Compendex
43. Accession number:20141717619080
Title:Pilot preparation technology and properties of new biochar-based nitrogenous fertilizers
Authors:Zhang, Wen1 ; Geng, Zengchao1 ; He, Xusheng1 ; Chen, Xinxiang1
Author affiliation:1 College of Nature Resources and Environment, Northwest A and F University, Yangling, Shannxi 712100, China
Corresponding author:Geng, Z. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:129-133 147
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Three kinds of biochar-based nitrogenous fertilizer (BBNF), which were composited with ammonium nitrate by simple-blending process, adsorbent process and reactive process, respectively, were produced. After that properties of the new BBNF were determined and their sustained release characteristics were evaluated. The results show that the pH values of all the three BBNF are all lower than that of the raw biochar. The BBNF prepared by reactive process loads maximum ammonium nitrate, followed by the BBNF prepared by adsorption process; the least is the BBNF prepared by blending process. The retention capacity of BBNF prepared by reactive process is better than the other two. The cumulative release rate of the three BBNF in aqueous solution is in line with the "S"-type release model. Compared with ammonium nitrate, all of the three BBNF have effectively controlled-release effect on nitrogen, and the BBNF produced by reactive process has the best effect.
Number of references:17
Main heading:Fertilizers
Controlled terms:Blending - Nitrates
Uncontrolled terms:Adsorption process - Bio chars - Controlled release - Preparation technology - Property analysis - Reactive process - Retention capacity - Sustained release
Classification code:802.3 Chemical Operations - 804 Chemical Products Generally - 804.2 Inorganic Compounds
DOI:10.6041/j.issn.1000-1298.2014.03.022
Database:Compendex
44. Accession number:20141717619093
Title:Turnover motion mechanism of automatic orientation of eggs according to pointed end and blunt end
Authors:Jiang, Song1 ; Sun, Ke1 ; Yang, Deyong2 ; Chen, Zhangyao3 ; Xu, Bin1 ; Wang, Guojiang1
Author affiliation:1 School of Food and Biological Engineering, Jiangsu University, Zhenjiang 212013, China
2 School of Mechanical Engineering, Jiangsu University, Zhenjiang 212013, China
3 Faculty of Civil Engineering and Mechanics, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Jiang, S. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:215-222
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:In order to develop the design method of automatic orientation of eggs according to the pointed end and the blunt end, the mechanism of turnover motion of eggs on the convey rollers was analyzed and verified under the conditions of different verities of eggs and different diameter, center distance of convey rollers. Results show that the turnover motion of eggs on convey rollers was accordance with the principle of the cam. The transmission model of the egg, convey rollers and guide rod was built; and theoretical calculation method of the rolling distance of egg and the action distance of guide rod were developed. The design and calculation methods of the processing aisle width and bending length of guide rod were also proposed. The results of theoretical calculation were consistent with the test results. The rolling distance of egg and the action distance of guide rod had a positive liner correlation with the center distance of convey rollers and had a positive liner correlation with the diameter of convey rollers. The determination coefficients were all above 0.94. It is feasible and correct to use principle of the cam to analysis the mechanism of turnover motion of eggs on convey rollers.
Number of references:15
Main heading:Rollers (machine components)
Controlled terms:Cams - Mechanisms
Uncontrolled terms:Design and calculation - Determination coefficients - Egg - Motion mechanisms - Pointed end and blunt end - Theoretical calculations - Transmission model - Turnover motion
Classification code:601.2 Machine Components - 601.3 Mechanisms
DOI:10.6041/j.issn.1000-1298.2014.03.035
Database:Compendex
45. Accession number:20141717619112
Title:Class II synthesis of conjugate cam mechanism with floating flat faced pushrod
Authors:Chang, Yong1, 2 ; Lin, Rongfu1 ; Li, Yanping1
Author affiliation:1 School of Mechanical Engineering, Jimei University, Xiamen 361021, China
2 Engineering Training Center, Jimei University, Xiamen 361021, China
Corresponding author:Li, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:333-340
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:By adopting the concepts of "rise and return travel" and "F/P type mechanism" and dividing the conjugate cam mechanism into main cam and assistant cam mechanism, which were studied respectively, the basic schematic diagram of instantaneous one dimensional linear area of the assistant cam (i.e. P type mechanism) and the curves of vC1-θ1, vC2-θ1 and uK-θ1 were proposed. And the differences between the main cam (i.e. F type mechanism) and the assistant cam (i.e. P type mechanism) were presented. The class II synthesis of P type mechanism and conjugate cam mechanism with floating flat face pushrod was resolved.
Number of references:15
Main heading:Cams
Controlled terms:Schematic diagrams
Uncontrolled terms:Cam mechanism - Class II - Floating pushrod - Linear areas - P-type
Classification code:601.3 Mechanisms - 703.1 Electric Networks
DOI:10.6041/j.issn.1000-1298.2014.03.054
Database:Compendex
46. Accession number:20141717619076
Title:Application of Lattice Boltzmann method to overland flow's movement and experimental verification
Authors:Zhang, Xiaona1 ; Feng, Jie2 ; Zhang, Donghui3
Author affiliation:1 College of Hydrometeorology, Nanjing University of Information Science and Technology, Nanjing 210044, China
2 Water Resources Research Institute, China Institute of Water Resources and Hydropower Research, Beijing 100044, China
3 School of Naval Architecture and Ocean Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, China
Corresponding author:Zhang, X. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:101-106
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:As the main reason for soil water erosion, the overland flow process should be simulated precisely to understand the mechanism of slop soil erosion process. Developed based on the kinetic theory, Lattice Boltzmann method has advantages of concise programming, parallel computing and complex geometric adaptability, etc. So its application in field of fluid motion becomes more and more extensively. The detailed steps about applying Lattice Boltzmann method to the movement of overland flow was given firstly, and then its validity was verified through artificial simulated rainfall experiment. The results indicate that if the time is processed by multi-scale approach and the space is not, the equilibrium distribution function is determined by the method of undetermined coefficients and multi-scale analysis, the distribution function about nodes of the upper boundary is replaced by the equilibrium distribution function through regarding the macroscopic upper boundary conditions as limiting conditions, and the distribution function about nodes of the lower boundary is set by extrapolation format of distribution function, Lattice Boltzmann method will successfully become a motion equation solver. The errors of runoff depth are within ±11%.
Number of references:19
Main heading:Computational fluid dynamics
Controlled terms:Equations of motion - Erosion - Parallel architectures - Rain - Soil moisture
Uncontrolled terms:Artificial simulated rainfall - Equilibrium distribution functions - Experimental verification - Lattice Boltzmann method - Method of undetermined coefficients - Multi scale analysis - Multi-scale approaches - Overland flow
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 443.3 Precipitation - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 722 Computer Systems and Equipment - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 921.2 Calculus
DOI:10.6041/j.issn.1000-1298.2014.03.018
Database:Compendex
47. Accession number:20141717619085
Title:Development of downstream processing technology for microalgae biofuel
Authors:Liu, Yuhuan1 ; Wang, Yingkuan2 ; Wang, Yunpu3 ; Yang, Huan3 ; Wu, Xiaodan3 ; Ruan, Rongsheng4
Author affiliation:1 State Key Laboratory of Food Science, Nanchang University, Nanchang 330047, China
2 Chinese Academy of Agricultural Engineering, Beijing 100125, China
3 Engineering Research Center of Biomass Conversion, MOE, Nanchang University, Nanchang 330047, China
4 Department of Bioproducts and Biosystems Engineering, University of Minnesota, St. Paul. MN55108, United States
Corresponding author:Liu, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:158-167
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Life cycle assessment of biodiesel produced from microalgae showed that the pure energy output was negative by the route of biodiesel (FAME), if the biodiesel was produced from high moisture content microalgae slurry by dry, cell disruption, solvent extraction of lipids, and transesterification. Therefore, passive choices are that mathane or bioethanol is obtained by anerobic digestion of microalgae slurry or their hydrolysate, or microalgae based bio-oils are obtained by fast pyrolysis and microwave assisted pyrolysis of dried microalgae biomass, or microalgae based bio-oils or syngas by hydrothermal treatment of microalgae slurry. Although the high heating value (HHV) of microalgae based bio-oils are much higher than lignocellulosic bio-oils, it can still not meet the demand of transportation liquid fuel due to its high nitrogen content, high oxygen content and instability. Possessing superiority of dehydration, oil extraction, protein and polysaccharide separation, or even in situ biodiesel production from high moisture content microalgae slurry, subcritical water treatment may become the prior research field of downstream processing technology for microalgae biofuels today. The most challenging research field is to know how to extract lipids, separate cytochrome, protein, polysaccharide from high moisture content microalgae slurry simultaneously under very mild reaction condition of enzymolysis, so that most of the functional components of the microalgae will be saved for value added comprehensive utilization. Last and key technology that may guide microalgae fuel to commercialization is how to manufacture renewable and high quality hydrocarbon diesel effectively from microalgae oil or its soap by microwave polarization decarboxylation.
Number of references:55
Main heading:Algae
Controlled terms:Biodiesel - Bioethanol - Carboxylation - Hydrocarbon refining - Life cycle - Lipids - Microorganisms - Moisture determination - Proteins - Pyrolysis - Solvent extraction
Uncontrolled terms:Comprehensive utilizations - Downstream-processing - Life Cycle Assessment (LCA) - Micro-algae - Microwave-assisted pyrolysis - Mild reaction conditions - Sub-critical water - Subcritical water treatment
Classification code:461.2 Biological Materials and Tissue Engineering - 461.9 Biology - 523 Liquid Fuels - 802.2 Chemical Reactions - 802.3 Chemical Operations - 804.1 Organic Compounds - 913.1 Production Engineering - 944.2 Moisture Measurements
DOI:10.6041/j.issn.1000-1298.2014.03.027
Database:Compendex
48. Accession number:20141717619095
Title:Enzymatic hydrolysis prediction model of bone collagen from pollock based on intrinsic viscosity
Authors:Hou, Hu1 ; Peng, Zhe1 ; Su, Shiwei1 ; Lu, Jiaohan1 ; Li, Bafang1
Author affiliation:1 College of Food Science and Engineering, Ocean University of China, Qingdao 266003, China
Corresponding author:Li, B. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:227-231
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Collagen was extracted from pollock bones and hydrolyzed with trypsin. An enzymatic hydrolysis prediction model of pollock bone collagen was established based on artificial neural network. It shows that the viscosity of collagen and its hydrolysates is decreased with the increasing of temperature. With the hydrolysis degree increasing, the peptide chain length, the molecular weight decrease, and the intrinsic viscosity decrease. In addition, it exhibited a one-to-one mapping relationship between the hydrolysis degree and the intrinsic viscosity. Using the intrinsic viscosity and the temperature as input parameters and the degree of hydrolysis as output parameter, a neural network was trained and simulated by 51 samples. The value of R2 is 0.9916 and the average relative error is only 2.5%, which indicates a good relevance between the sample actual value and the simulation value. Then three verification tests were performed using the prediction model, and the theoretical value is in agreement with the experimental value. The relative error is in range of 1.06%~4.32%. Therefore, the model can predict and monitor the hydrolysis of pollock bone collagen.
Number of references:18
Main heading:Collagen
Controlled terms:Bone - Enzymatic hydrolysis - Mathematical models - Neural networks - Viscosity
Uncontrolled terms:Average relative error - Degree of hydrolysis - Experimental values - Hydrolysates - Intrinsic viscosity - One-to-one mappings - Prediction model - Verification tests
Classification code:461.1 Biomedical Engineering - 461.2 Biological Materials and Tissue Engineering - 631.1 Fluid Flow, General - 804.1 Organic Compounds - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.037
Database:Compendex
49. Accession number:20141717619074
Title:Spatial variability of soil nitrogen and phosphorus in small watershed
Authors:Si, Han1 ; Zhang, Zhanyu1 ; Lü, Mengxing1 ; Feng, Genxiang1
Author affiliation:1 College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China
Corresponding author:Zhang, Z. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:90-96
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Geo-statistics combined with classical statistics were applied to analyze the spatial distribution of soil nitrogen (N) and phosphorus (P) content under three different land uses in Chahe watershed at the lower Yangtze River. The results showed that soil N and P content distribution varied significantly in paddy, upland, and vacant land, while the coefficient of variation also varied greatly among the three land uses. All spatial distributions of N and P content values were anisotropic and directions of most long axes were northwest-southeast. Major ranges in topsoil were between 750~950 m with the order of total P(TP)>ammonia N (AN)>total N (TN)>available P (AP)>nitrate N (NN). Higher content of TN was mainly concentrated in the southern part of the small watershed and the gradient direction was consistent with the direction of surface runoff, while distribution of TP was significantly affected by farming and soil particle movement, and the high level of TP was appeared in the accumulation area of the south of small watershed and the north of arid region. TN and TP showed similar structural characteristics under the three farmland types, while both the autocorrelation scales in paddy land were larger than those in upland. Variation of spatial autocorrelation scales showed good consistency with the coefficient of variation. Research results provided a scientific basis for the control of N and P losses in agricultural production and the establishment of non-point source pollution model.
Number of references:20
Main heading:Watersheds
Controlled terms:Arid regions - Autocorrelation - Farms - Land use - Phosphorus - Pollution control - River pollution - Spatial distribution - Spatial variables measurement
Uncontrolled terms:Agricultural productions - Coefficient of variation - Farmland type - Geo-statistics - Non-point source pollution - Spatial autocorrelations - Spatial variability - Structural characteristics
Classification code:403 Urban and Regional Planning and Development - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 453 Water Pollution - 454.2 Environmental Impact and Protection - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 922 Statistical Methods - 943.2 Mechanical Variables Measurements
DOI:10.6041/j.issn.1000-1298.2014.03.016
Database:Compendex
50. Accession number:20141717619102
Title:Infrared and visible light images fusion algorithm based on non-subsampled Shearlet transform
Authors:Gao, Guorong1 ; Liu, Yanping1
Author affiliation:1 College of Science, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Liu, Y. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:268-274
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Focusing on the fusion problem of infrared and visible light images in the same scene, a novel multirsensor image fusion algorithm based on the non-subsampled Shearlet transform was proposed. Firstly, the NSST was performed on the source images at different scales and directions, thus the low frequency subband coefficients and varieties of directional bandpass subband coefficients were obtained. Secondly, the low frequency subband coefficients of the fused image were selected based on the local structural similarity and local energy of the two source images, and the bandpass subband coefficients of the fused image were selected based on the firing times of the pulse coupled neural network (PCNN), so the NSST coefficients of fused image was got. Finally, the fused image was obtained by performing the inverse NSST on the combined coefficients. Quantitative and qualitative analysis of the experimental results demonstrated that the proposed method performs significantly better than the other five related methods.
Number of references:16
Main heading:Image fusion
Controlled terms:Algorithms - Fusion reactions - Infrared imaging - Neural networks
Uncontrolled terms:Fusion algorithms - Image fusion algorithms - Pulse coupled neural network - Quantitative and qualitative analysis - Shearlet transforms - Structural similarity - Subband coefficients - Visible light images
Classification code:621.2 Fusion Reactors - 723 Computer Software, Data Handling and Applications - 746 Imaging Techniques - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2014.03.044
Database:Compendex
51. Accession number:20141717619107
Title:D-H quaternion method for inverse kinematics of serial mechanisms
Authors:Zhang, Zhonghai1 ; Li, Duanling1
Author affiliation:1 School of Automation, Beijing University of Posts and Telecommunications, Beijing 100876, China
Corresponding author:Li, D. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:299-304
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The normal quaternion method of inverse kinematics of serial mechanisms has the limitation of lacking equations and is difficult to solve. In order to solve these problems and put forward a new method of inverse kinematics of serial mechanisms, a D-H quaternion method for inverse kinematics of serial mechanisms is proposed. The general equation of quaternion transformation including D-H parameters was given first. Two equations of position and posture were obtained by separating the general equation of quaternion transformation. By these two equations, an equation system with seven equations was constructed, which met the number requirement of the equations for inverse kinematics of serial mechanisms with more than four degrees of freedom. In order to lower the difficulty in solving equations, the degree of posture equation was reduced to half by taking half of the trigonometric function in the original posture equation to construct a new posture equation. By using the proposed D-H quaternion method, the inverse kinematics of PUMA robot was analyzed, and eight groups of inverse solutions were obtained. Three dimensional models of PUMA robot were established based on the eight groups of inverse solutions. Measured results of end positions and postures in the three dimensional models are consistent with the given values. The example of PUMA robot shows the correctness and validity of the proposed D-H quaternion method.
Number of references:21
Main heading:Inverse kinematics
Controlled terms:Degrees of freedom (mechanics) - Robots - Three dimensional
Uncontrolled terms:D-H quaternion - Four-degrees-of-freedom - General equations - PUMA robots - Quaternion methods - Serial mechanism - Three-dimensional model - Trigonometric functions
Classification code:731.5 Robotics - 902.1 Engineering Graphics - 931.1 Mechanics
DOI:10.6041/j.issn.1000-1298.2014.03.049
Database:Compendex
52. Accession number:20141717619063
Title:Experiment of waste heat recovery system with R245fa as working fluid
Authors:Wei, Mingshan1 ; Shi, Lei1 ; Song, Panpan1 ; Wang, Fangjun1 ; Ma, Chaochen1
Author affiliation:1 School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
Corresponding author:Wei, M. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:26-31
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:To improve vehicle engine fuel economy, an organic Rankine cycle (ORC) system was designed to recover waste heat from heavy-duty diesel engines through their exhaust air. R245fa was selected as the working fluid after compared with several other organic fluids. A test platform for waste heat recovery was built, which includes an ORC circuit, an energy conversion and consumption device, a data measure and acquisition unit and a heat supply module. The feasibility of using R245fa as working fluid in the heavy-duty diesel engine ORC system was proved by experiments. The maximum power output of the system is 490 W. The experiments indicate that the matching of the expander, the generator and the ORC system is the key factor restricting the power output. The system cycle efficiency increases with the evaporating pressure increase.
Number of references:17
Main heading:Fluids
Controlled terms:Diesel engines - Energy conversion - Experiments - Fuel economy - Rankine cycle - Waste heat - Waste heat utilization
Uncontrolled terms:Heavy-duty diesel engine - Maximum power output - Organic Rankine Cycle(ORC) - Organic Rankine cycles - R245fa - Testing apparatus - Thermal efficiency - Waste heat recovery systems
Classification code:521 Fuel Combustion and Flame Research - 525 Energy Management and Conversion - 612.2 Diesel Engines - 631 Fluid Flow - 641.1 Thermodynamics - 901.3 Engineering Research
DOI:10.6041/j.issn.1000-1298.2014.03.005
Database:Compendex
53. Accession number:20141717619113
Title:Flow boiling instabilities controlled by seed bubbles in microchannels
Authors:Zong, Luxiang1 ; Xu, Jinliang2 ; Liu, Guohua3
Author affiliation:1 State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China
2 Beijing Key Laboratory of Multiphase Flow and Heat Transfer for Low Grade Energy, North China Electric Power University, Beijing 102206, China
3 School of Energy and Environment, Anhui University of Technology, Maanshan 243002, China
Corresponding author:Xu, J. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:341-346
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:A simultaneous optical visualization experimental system was set up, and a parallel triangle silicon microchannel heat sink was used as the test section. Five platinum film microheaters was etched at the top glass cover surface and located at the microchannel entrance, acting as a seed bubble generator array. The microscale flow boiling instability under different seed bubble frequencies was experimental examined. The results show that the seed bubble frequency is an important parameter to control flow boiling instability. In the single liquid flow region, seed bubbles have negligible effect on flow. In the two-phase flow region, with heat flux increasing, pressure drop increases linearly and the temperature of the heating wall surface increases exponentially. Moreover, higher pressure drop could be approached with lower wall temperatures and higher bubble triggering frequency. With the same heat flux, the seed bubbles triggered with high frequency can completely eliminate flow boiling instabilities, heating wall temperature could be dramatically decreased, and the uniformity of the temperature could be promoted significantly.
Number of references:20
Main heading:Microchannels
Controlled terms:Heat flux - Pressure drop
Uncontrolled terms:Bubble frequency - Bubble generators - Experimental system - Flow boiling instabilities - Optical visualization - Silicon microchannel heat sinks - Triggering frequency - Wall temperatures
Classification code:604 Metal Cutting and Machining - 631 Fluid Flow - 631.1 Fluid Flow, General - 641.2 Heat Transfer
DOI:10.6041/j.issn.1000-1298.2014.03.055
Database:Compendex
54. Accession number:20141717619105
Title:Design of bus-style soft motion control engine based on SMP
Authors:Sun, Haochun1 ; Zhang, Chengrui1 ; Hu, Tianliang1
Author affiliation:1 School of Mechanical Engineering, Shandong University, Ji'nan 250061, China
Corresponding author:Zhang, C. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:288-292
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:The design method of real-time Ethernet EtherMAC master based on SMP architecture was proposed, while a field bus oriented motion control engine was developed, which was running in kernel space. To make the procedure of motion control program development easy, a cross-platform programming interface was created by making memory stack in a shared memory for transferring parameters. To reduce the coupling between the motion control engine and the field bus, and to enhance the adaptability of the engine to any other field bus, a bus abstraction layer was proposed and designed. The result from prototype shows that the motion control engine has a better ease of use and a better portability, and indirectly enhances the EtherMAC real-time performance.
Number of references:16
Main heading:Motion control
Controlled terms:Buses - Engines
Uncontrolled terms:Abstraction layer - Control program - Cross-platform - Motion control engines - Programming interface - Real time Ethernet - Real time performance - Real-time extension
Classification code:612 Engines - 663.1 Heavy Duty Motor Vehicles - 731.3 Specific Variables Control
DOI:10.6041/j.issn.1000-1298.2014.03.047
Database:Compendex
55. Accession number:20141717619094
Title:Design and test of measurement system for freezing point of living tissue of fruits and vegetables
Authors:Zhang, Min1 ; Yuan, Haitao1 ; Huang, Ruguo1 ; Lu, Jiahua1 ; Xie, Jing1 ; Guo, Xiaobin1
Author affiliation:1 College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
Corresponding author:Zhang, M. ([email protected])
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:45
Issue:3
Issue date:March 2014
Publication year:2014
Pages:223-226
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery
Abstract:Measurement of freezing point temperature for living tissue of fruits and vegetables plays an important role for study on chilling, freezing injury mechanism and freezing process of fruits and vegetables. The freezing point temperature obtained by traditional measurement methods is difficult to be used to direct industrial process, because the temperature is from fruit and vegetable juice temperature, has great difference with the freezing point of living tissue, and is greatly influenced by the shapes and sizes of fruits and vegetables by putting the thermocouple or thermal resistor into fruit and vegetable tissues. The measurement system for freezing point of living tissue of fruits and vegetables was developed based on one-dimension unsteady state semi-infinity heat conduction theory. The results show clearly that this measurement is convenient and reliable for determining freezing point of living tissue of fruits and vegetables. It is convenient, time saving, samples saving and environment thermal disturbance less. It has a good application prospect in determining freezing point of fruits and vegetables.
Number of references:15
Main heading:Tissue
Controlled terms:Freezing - Fruits - Measurements - Thermocouples - Vegetables
Uncontrolled terms:Application prospect - Freezing point - Fruit and vegetables - Fruits and vegetables - Heat conduction theory - Living tissues - Measurement methods - Measurement system
Classification code:461.2 Biological Materials and Tissue Engineering - 821.4 Agricultural Products - 822.2 Food Processing Operations - 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 - 944.5 Temperature Measuring Instruments
DOI:10.6041/j.issn.1000-1298.2014.03.036
Database:Compendex
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