Author affiliation:1 School of Mechanical and Electronic Engineering, Jingdezhen Ceramic Institute, Jingdezhen 333403, China
2 College of Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Xiao, Z. (cauxiao@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:183-186
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Based on the theoretical analysis of flow characteristics between superheated steam and granules materials in the fluidized bed drying chamber, the fluidization experiment with superheated steam and hot air was conducted by using the dried rapeseed particles as the experimental material. A small experimental device was established. The experimental results showed that the operating velocity of superheated steam fluidized bed drying was faster than the traditional hot air fluidized bed dying under the same conditions. Under the given conditions, the critical fluidization velocity of the rapeseed particles was 1.26 m/s during superheated steam fluidized bed drying.
Number of references:11
Main heading:Steam
Controlled terms:Air - Experiments - Fluidization - Fluidized bed process - Fluidized beds - Oilseeds - Particles (particulate matter)
Classification code:901.3 Engineering Research - 821.4 Agricultural Products - 804 Chemical Products Generally - 802.3 Chemical Operations - 802.1 Chemical Plants and Equipment - 614 Steam Power Plants - 533.1 Ore Treatment
DOI:10.6041/j.issn.1000-1298.2013.07.032
Database:Compendex
2. Accession number: 20132916509675
Title: Positioning assembly system for self-locking bolt of driving wheel axle based on fuzzy prediction
Author affiliation:1 College of Information Science and Technology, Dalian Maritime University, Dalian 116026, China
2 Department of The Third Assembly Plant, The First Tractor Co. Ltd., Luoyang 471004, China
Corresponding author:Wang, G. (gfwangsh@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:293-298
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:With the realization automation assembly for the tractor of driving wheel axle, the control method of fuzzy predictionwas proposed for self-locking bolt tightening assembly. According to the bolt tightening characteristic, the clamping force, torque and angle were predicted, and the self-locking bolt tightening process for the tractor of driving wheel axle assembly were controlled by using the embedded assembly controller. Moreover, the positioning device of lock blade and assist device were designed with combining the technology of fiber optical sensor detection and mechanical design. By the application of intelligent fuzzy control arithmetic, the multivariable target fuzzy intelligent control for axial pre-tightening force, self-locking bolt tightening torque and angle position of driving wheel axle were achieved. Verified by the actual production process, a self-locking bolt assembly question with the function of lock blade positioning was resolved. It had higher prediction accuracy and improved the assembling quality and efficiency.
Classification code:921 Mathematics - 913.1 Production Engineering - 731 Automatic Control Principles and Applications - 663.2 Heavy Duty Motor Vehicle Components - 663.1 Heavy Duty Motor Vehicles - 605 Small Tools and Hardware - 601.2 Machine Components
DOI:10.6041/j.issn.1000-1298.2013.07.050
Database:Compendex
3. Accession number: 20132916509648
Title: Numerical simulation on biomass gasification tar separator
Author affiliation:1 School of Mechanical Engineering, Changzhou University, Changzhou 213016, China
Corresponding author:Fu, S. (fushch711@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:133-137
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:According to physical properties of the tar and separate requirements, a type of tar separator which is applicable to dry method of removing the tar was designed. This type of tar separator can cool and condensing the tar, at the same time separates the droplets of the tar. It can be seen from the numerical simulation results of gas flow field, the results of gas movement of heat transfer show that wall cooling has a great influence on temperature field in the cyclone separator. The temperature field also presents the characteristics that the surrounding area gradually reducing with surrounding downward flow, and the central zone rising up with centering upward flow, and the radial temperature gradually reducing in the cyclone separator. The decrease of temperature leads to the increase in gas density and the decrease in gas viscosity and the increase in the tar droplets viscosity. Wall cooling can reduce the cut size, as well as improve the separation efficiency of biomass gasification gas tar through the tar droplet separation theory and the physical analysis of tar.
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Yang, P. (yang-pl@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:98-106 97
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Over the course of one summer maize and winter wheat rotation cycle, three irrigation treatments (ground water with a quota of 52.5 mm; reclaimed water with a quota of 52.5 mm; reclaimed water with a quota of 105 mm) were set up, and in each treatment, the soluble K , Ca2 , Cl- and the electric conductivity (EC) leaching and migration in 0-450 cm soil were studied. The results showed that the soil salinity content and EC value were in the following descending order: 380-450 cm loam soil layer, 0-120 cm loam soil layer, and 120-380 cm sandy soil layer. Soluble K and Cl- in reclaimed water had a strong leaching and migration ability, and reached the 450 cm depth, and the influences of reclaimed water irrigation on soluble K and Cl- changes were mainly in 0-450 cm soil layer and 0-250 cm soil layer, respectively. Soluble Ca2 and EC reached the 380 cm depth, but the influences of reclaimed water irrigation on soluble Ca2 and EC changes were mainly in 0-120 cm soil layer. The 380-450 cm soil layer played a role as a block layer for soil salinity leaching, and decreased the pollution risk of soil salinity ion to groundwater. It suggested that irrigation with reclaimed water with a quota of 52.5 mm, while irrigation 1time and 4 times or less during the summer maize and winter wheat growing seasons, respectively.
Author affiliation:1 Key Laboratory of Bionic Engineering, Ministry of Education, Jilin University, Changchun 130025, China
2 China Academy of Space Technology, Beijing 100094, China
Corresponding author:Li, J. (jqli@jlu.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:264-268
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The rut geometric analysis is necessary for studying the interaction between the driving wheel and the loose soil. A laser scanner that consisted of a laser sensor and a 2-D traversing frame was developed to measure the digit parameters of ruts in the soil bin which were produced by the rigid wheel on loose soil. The maximum scanning area was 650 mm×400 mm, measurement range was 0.05-65 m and scanning resolution was 0.1 mm. A laser scanner with 1-D traversing frame which might be more appropriate for the measurements of rut deformation in the infield of rover was also discussed. The experimental results showed that the scanners could obtain the sections and the 3-D graphics of the surface of ruts by using contactless measuring method without disturbing the ruts.
Title: Real-time motion detection for intelligent agricultural vehicle based on stereo vision
Authors:Tian, Guangzhao1 ; An, Qiu1 ; Ji, Changying1 ; Gu, Baoxing1 ; Wang, Haiqing1 ; Zhao, Jiandong1
Author affiliation:1 College of Engineering, Nanjing Agricultural University, Nanjing 210031, China
Corresponding author:Ji, C. (chyji@njau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:210-215
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:A real-time motion detection method based on stereo vision was designed in order to meet the need of precise navigation for intelligent agricultural vehicle. Multi-thread feature points detection was used to improve the efficiency of traditional SIFT algorithm. Normalized comprehensive distance algorithm (NCDA) was used to delete the error matched points. Finally, vehicle motion was calculated by the position variation of feature points in adjacent moment. Experiments showed that the average detection time spent was reduced and computing efficiency was raised up. Error matched points were successfully recognized and erased by NCDA. Measurement errors in one time were less than 0.0045 m in x-and z-axis when the speed was 0.8 m/s and image grabbing frequency was 5 Hz. Measurement errors in x-and z-axis were less than 0.15 m when the vehicle kept moving for 10 s.
Classification code:922 Statistical Methods - 921 Mathematics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 723.5 Computer Applications - 723 Computer Software, Data Handling and Applications - 716.3 Radio Systems and Equipment - 432 Highway Transportation
DOI:10.6041/j.issn.1000-1298.2013.07.037
Database:Compendex
7. Accession number: 20132916509650
Title: Development trend of food quality safety traceability technology
Author affiliation:1 College of Engineering, China Agricultural University, Beijing 100083, China
2 Beijing Laboratory of Food Quality and Safety, Beijing 100083, China
3 College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Fu, Z. (fzt@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:144-153
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Food quality safety traceability technology and its application system development are worldwide focus and hot topic. Based on the literature review, the important meaning of food quality safety traceability technology was presented. The significance, development tendency and the main characteristic were summarized from four aspects: traceability unit dividing, information collection, information transformation, and information processing. The result showed that traceable unit in food quality safety traceability technology was developed from experienced dividing to model optimization, information acquisition technology was improved from manual collection to intelligent collection, information transmission technology was changed from independent to standardized transmission, and information processing technology was changed from manual analysis to intelligent decision.
Number of references:66
Main heading:Technology transfer
Controlled terms:Data processing - Food safety
Uncontrolled terms:Information acquisitions - Information collections - Information processing technology - Information transformations - Information transmission - Intelligent decisions - Key technologies - Traceability systems
Classification code:461.6 Medicine and Pharmacology - 723.2 Data Processing and Image Processing - 911.2 Industrial Economics
DOI:10.6041/j.issn.1000-1298.2013.07.025
Database:Compendex
8. Accession number: 20132916509630
Title: Effect of spark timing on combustion and particle emission for gasoline direct injection engine
Author affiliation:1 State Key Laboratory of Engines, Tianjin University, Tianjin 300072, China
Corresponding author:Pan, S. (suozhup@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:23-27
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The effects of sparking timing on combustion process and particle emission were investigated experimentally on a gasoline direct injection engine by using combustion analyzer and DMS500 fast particulate spectrometer. Results showed that with the delay of spark timing, flame development duration decreased gradually, and rapid burning duration increased gradually. Peak value of heat release rate and cylinder mean temperature showed a gradually decrease and backward shift, which induced a slow heat release process and high cylinder temperature in expansion stroke. Also, spark timing delay led to decrease in the peak cylinder pressure. Moreover, exhaust particles from GDI engine exhibited a bimodal size distribution including nucleation mode and accumulation mode particles. As the reduce of spark advance, total particle number concentration and peak value of particle number density in nucleation mode and accumulation mode decreased gradually, and peak size of accumulation mode particles showed a decreasing trend, but spark timing exhibited a slight influence on peak size of nucleation mode particles.
Number of references:16
Main heading:Gasoline
Controlled terms:Combustion - Direct injection - Electric sparks - Engines - Neutron emission - Nucleation
Uncontrolled terms:Bimodal size distribution - Combustion pro-cess - Gasoline direct injection - Gasoline direct injection engines - Gasoline engines - Nucleation mode particles - Particle number concentration - Spark timing
Classification code:933.1.2 Crystal Growth - 932.1 High Energy Physics - 701.1 Electricity: Basic Concepts and Phenomena - 612 Engines - 523 Liquid Fuels - 521.1 Fuel Combustion - 521 Fuel Combustion and Flame Research
DOI:10.6041/j.issn.1000-1298.2013.07.005
Database:Compendex
9. Accession number: 20132916509664
Title: Segmentation of remote sensing images based on adaptive global threshold and fused markers
Authors:Li, Li1 ; Chai, Wenting1 ; Mei, Shuli1
Author affiliation:1 College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Li, L. (lilio@263.net)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:222-228
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Based on the method of adaptive global threshold and markers fusion, an algorithm was proposed in order to solve the problems of over-segmentation and the under-segmentation caused by incomplete marking, which might occur concurrently during the segmentation of remote sensing building images. First, the algorithm was used in wavelet transform to generate image gradient according to the distribution and texture characteristics of buildings, and the generated gradient image was filtered through morphological reconstruction. Then, the background markers were extracted by local minimum and the building makers by adaptive global threshold. After both markers were fused, they were used to modify the weighted pixel Sobel gradient image for accurate image segmentation. The experimental results demonstrated that the algorithm could make up for a lack of the local extreme marker, and significantly inhibited both over-segmentation and the under-segmentation. As a result, the segmentation accuracy reached to 90.7%.
Author affiliation:1 College of Mechanical Engineering and Applied Electronics Technology, Beijing University of Technology, Beijing 100124, China
Corresponding author:Yu, Y. (yqyu@bjut.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:274-278
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Compliant joint is mostly applied in the field of micro-operations. Instead of traditional kinematic pairs, compliant joints were designed by using method of structural parameters to satisfy the experimental requirement, and a parallel robot with compliant joints was proposed. Combined with the control unite and OPTOTRAK measurement, the experiment system of a 3-DOF compliant parallel robot was set up for the mechanism dynamics modeling, analysis, design, planning, and control system. The experimental study of the parallel robot with compliant joints was presented, compared to that with revolute joints. Through comparative analysis, relative errors of the experimental index were controlled within the allowable range. The experimental result showed the validity of compliant joints in replacing the kinematic pairs of parallel robots.
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Yang, P. (yangpeiling@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:113-120
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Taking hillside orchards in Huairou district as the experimental plot, PAM and SAP were selected to apply for controlling manure pollution in this orchard. The antifouling effect of PAM on sloping field was tested by artificial rainfall experiment, and the outdoor monitoring experiment was carried out from 2010 to 2011. After applying the proposed technology, soil erosion and nutrient runoff in soil slope, also the soil water content and nutrient migration in soil profile were discussed. The results showed that PAM could reduce event mean concentration and pollution emission load of individual rainfall by 5%-8% and 16%-22%, respectively. PM treatment is the best in this experiment. Compared with control treatment PS0, chemical antifouling treatments PS1and PS2could promote the water content of soil root layer by 10.4% and 23.7%, increase nutrient content by 3.8% and 22.3%, reduce sediment in slope runoff by 30.7% and 61.7%, and reduce nitrate nitrogen content in slope runoff by 14.7% and 30.7%, respectively.
Classification code:901.3 Engineering Research - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 483.1 Soils and Soil Mechanics - 454.3 Ecology and Ecosystems - 454.2 Environmental Impact and Protection - 444.1 Surface Water - 443.3 Precipitation
DOI:10.6041/j.issn.1000-1298.2013.07.020
Database:Compendex
12. Accession number: 20132916509642
Title: Relationship between deep soil water vertical variation and root distribution in dense jujube plantation
Author affiliation:1 College of Water Resources and Architectural Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
2 Institute of Soil and Water Conservation, Northwest A and F University, Yangling, Shaanxi 712100, China
3 Institute of Soil and Water Conservation, CAS and MWR, Yangling, Shaanxi 712100, China
4 College of Natural Resources and Environment, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Wang, Y. (gjzwyk@sina.com.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:90-97
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to investigate the relationship between deep soil water (below 2 m) vertical variation and root distribution in the nine-year-old dense jujube plantation in Loess hilly region. The soil core method and oven drying method were used to determine fine root dry weight density and soil water content. Sequential cluster analysis method was adopted to stratify the whole soil water profile into three layers, i.e. strong depletion layer (2.0-4.4 m), less strong layer (4.4-5.0 m) and weak depletion layer (5.0-7.0 m) based on the combined analysis of soil water content and the root dry weight density. This stratification result could well reflect soil water characteristic absorbed by root. In the strong depletion layer, fine root dry weight density decreased fluctuantly with the increase of soil depth, but soil water content was low and stable. While in the less strong layer, fine root dry weight density decreased continuously, soil water content presented increasing tendency. The maximum fine root depth was 5 m, there was no fine root in the weak depletion layer and soil water content increased obviously. This study determine the soil layer range of deep soil water depletion degree in densely jujube plantation. It shows that root distribution characteristic has an important effect on the deep soil water variation.
Author affiliation:1 Institute of Water Resources and Hydropower Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
2 Montgomery and Barnes, Inc., Houston 77067, United States
Corresponding author:Wang, Z. (wangzz0910@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:107-112
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:A method called "slot and hole" was proposed for preventing the soil and water loss of sloping farmland in Loess Plateau. Due to gravity load, slop surface runoff was intercepted and stored in a hole through a slot to form a soil reservoir. By applying this method, the convergence of slop runoff was avoided, and water evaporation also decreased. The loss of soil and water was thus prevented. Some skills for application of this method were pointed out. Additionally, the design standard of "slot and hole" method was proposed. Based on the principle that the corresponding standard runoff was totally stored in the hole, the reasonable layout scheme was determined, and the relationship of the diameter of the hole to the distance between two adjacent slots was obtained. Moreover, the formatting process of the hole and seepage process were simulated by employing FEM, and then the variation laws of physical and mechanical parameters of the soil around the hole were obtained. The results demonstrated that the physical and mechanical parameters of the soil around the hole varied significantly in the area of 0.4 times diameter of the hole, and the porosity and permeability coefficient of soil decreased as the dry density and deformation modulus of soil increased. The closer the area was to the hole, the smaller the porosity and permeability coefficient and the larger the dry density and deformation modulus were. After seepage analysis, the strength of the hole decreases slightly and certain deformation occurred.
Uncontrolled terms:Deformation modulus - Physical and mechanical parameters - Sloping farmlands - Slot and hole - Soil and water conservation - Soil and water loss - Structural stabilities - Water evaporation
Classification code:483.1 Soils and Soil Mechanics - 801 Chemistry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 931 Classical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science - 961 Systems Science - 483 Soil Mechanics and Foundations - 407 Maritime and Port Structures; Rivers and Other Waterways - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 441 Dams and Reservoirs; Hydro Development - 441.2 Reservoirs - 444 Water Resources - 444.1 Surface Water
DOI:10.6041/j.issn.1000-1298.2013.07.019
Database:Compendex
14. Accession number: 20132916509628
Title: Simulation on working process of low-pressure air-assisted direct injection gasoline engine
Author affiliation:1 Tianjin Internal Combustion Engine Research Institute, Tianjin University, Tianjin 300072, China
Corresponding author:Hu, C. (cmhu@tju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:12-16 22
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The working process of a 1.2 L low-pressure air-assisted direct injection gasoline engine was studied based on simulation. The flow of working fluid in intake port and cylinder were analyzed. The cylinder mixture concentration distribution at 20°CA between the before and after improvement of combustion chamber under different injection timings were compared. The effect of ignition timing on engine combustion process was discussed. Results show that the overall uniformity of cylinder mixture concentration distribution at 20°CA is better than the original engine, and the mixture concentration for stable ignition could be formed in the two spark plugs gap with the injection timings of 420°CA and 440°CA. With the advance of ignition timing, combustion advances gradually, the maximum cylinder pressure and the maximum pressure rise rate increase. In addition, with the delay of ignition timing, flame development duration decreases gradually, while rapid burn duration decreases at the beginning and then increases.
Author affiliation:1 College of Mechanical and Electronic Engineering, Shandong Agricultural University, Taian 271018, China
2 School of Mechanical Engineering, Northwestern Polytechnical University, Xi'an 710072, China
Corresponding author:Liu, X. (wjbliu@sdau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:256-263
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:A comprehensive survey of the up-to-date methods and technologies for 3-D CAD model retrieval was presented. Firstly, the architecture of 3-D CAD model retrieval system was introduced, and a detailed survey on current 3-D CAD model retrieval was given from text-based retrieval, content-based retrieval and semantic-based retrieval. Then, the existing 3-D CAD model retrieval system and the application of 3-D CAD model retrieval were also introduced. Finally, some challenges and the future directions of 3-D CAD model retrieval were indicated. The proposed CAD retrieval technology provided fully retrieval support for conceptual design, detailed design, polytechnical design, and product design. It also enforced the capability of enterprise product model designing and reuse of manufacturing information.
Number of references:52
Main heading:Three dimensional
Controlled terms:Computer aided design - Conceptual design - Content based retrieval - Information retrieval - Product design - Surveys
Title: On-line detection of firmness of 'cuiguan' pear using visible/near infrared spectrum
Authors:Ma, Guang1 ; Sun, Tong2
Author affiliation:1 College of Mechanical and Electrical Engineering, Jinhua Polytechnic, Jinhua 321017, China
2 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
Corresponding author:Ma, G. (mgjhc@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:170-173
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The objective of this research was to measure firmness of 'Cuiguan' pears on-line by using visible/near infrared spectrum, also the effect of different pretreatment methods and different points of smoothness on calibration performance were studied. The spectrometer of USB4000 was used to acquire the spectra of 'Cuiguan' pears at fruit moving speed of 0.5 m/s, and partial least squares (PLS) was used to develop calibration. The total number of samples used was 176, and 119 samples were used as calibration set, 57 samples were used as validation set. The results indicated that it was feasible to measure firmness of 'Cuiguan' pears by using visible/near infrared spectrum, and wavelength range of 580-840 nm was suitable for calibration. The best calibration performance was obtained when using spectra pretreated by first derivative combined with SNV, the correlation coefficient, root mean square error of calibration (RMSEC) and root mean square error of validation (RMSEP) were 0.820, 2.50 N and 3.02 N, respectively. For Savitzky-Golay method, the five data points obtained the best calibration, the correlation coefficient, RMSEC and RMSEP were 0.848, 2.31 N and 2.85 N, respectively.
Number of references:15
Main heading:Fruits
Controlled terms:Calibration - Least squares approximations - Mean square error - Spectroscopy
Uncontrolled terms:Correlation coefficient - Firmness - On-line detection - Partial least square (PLS) - Pear - Root mean square error of calibrations - Root mean square errors - Visible/near infrared
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 921.6 Numerical Methods - 801 Chemistry - 731.1 Control Systems - 821.4 Agricultural Products
DOI:10.6041/j.issn.1000-1298.2013.07.029
Database:Compendex
17. Accession number: 20132916509633
Title: Simulation of mixed refrigerant for diesel engine waste heat recovery system under variable conditions
Author affiliation:1 College of Environmental and Energy Engineering, Beijing University of Technology, Beijing 100124, China
2 School of Mechatronic Engineering, North University of China, Taiyuan 030051, China
Corresponding author:Zhang, H. (zhanghongguang@bjut.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:39-44
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:According to the characteristics of exhaust gas of diesel engine under variable conditions, a waste heat recovery system of organic Rankine cycle was designed. Under the different evaporation pressures, the effects of azeotropic mixtures and zeotropic mixtures on the performance of waste heat recovery system of organic Rankine cycle of vehicle diesel engine in variable conditions were discussed. Combined with the practical projects, the mixtures which was the most suitable for this system was chosen. The results showed that the mean value of exergy destruction rate of the ORC system using the zeotropic mixtures R415B was 38% lower than the azeotropic mixtures R508A under variable conditions. Through the comparative analysis, the zeotropic mixtures R415B was the most suitable for the waste heat recovery system of organic Rankine cycle of vehicle diesel engine under variable conditions, the maximum net power output value was about 27.60 kW.
Author affiliation:1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
2 XJ Group Corporation XJ Power Co. Ltd., Xuchang 461000, China
Corresponding author:Qiu, Z. (zjqiu@zju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:229-234
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The existing methods of leaf area measuring would cause certain damage to the leaf, so a measurement method of the leaf area in natural growing state was put forward. The digital camera was calibrated to get camera parameters; then leaf images at various angles in natural growing state were shot and processed by PhotoModeler software. The 3-D point cloud model of leaf was built up. The 3-D surface modeling and surface area calculating of leaf were achieved by using Matlab software. The measuring results and the calculating results with combination method of scanner and Photoshop software were compared. It showed that the accuracy of calculating results reached to 99%.
Author affiliation:1 School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
Corresponding author:Liu, F. (Prof.LiuFS@yahoo.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:6-11
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to solve the matching problem, the mathematic model of starting process of free-piston engine-generator was analyzed. By simplifying the displacement and velocity of the piston, simplified expressions of driving force of linear motor was deduced. The result showed that the larger piston mass could advisably increase inertial force and decrease the minimum starting force, but reduce the maximum speed and slower the starting process. Less frictional coefficient and effective compression ratio could also reduce the starting force. With the simplified formula, the starting process of a prototype free-piston engine-generator was analyzed and the minimum starting force was achieved.
Number of references:10
Main heading:Engine pistons
Controlled terms:Compression ratio (machinery) - Engines - Starting
Classification code:612 Engines - 617 Turbines and Steam Turbines
DOI:10.6041/j.issn.1000-1298.2013.07.002
Database:Compendex
20. Accession number: 20132916509652
Title: Applications of laser doppler vibrometer technology in nondestructive detection of agro-product quality
Authors:Cui, Di1 ; Zhang, Wen1 ; Ying, Yibin1
Author affiliation:1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
Corresponding author:Ying, Y. (ybying@zju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:160-164
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Accurate detection of agro-product quality can provide reliable basis for postharvest preservation, determining when to sell, predicting shelf-life and sorting. Laser Doppler vibrometer (LDV) technology is based on the Doppler-effect sensing the frequency shift of back scattered light from a moving surface, and has the advantages of high sensitivity, non-contact measurement, avoiding mass loading implication and so on. This technology can be used for nondestructive evaluation of agro-product quality by inspecting its vibrational properties. The development and principle of LDV technology, and its applications in nondestructive detection of agro-product quality were introduced.
Number of references:30
Main heading:Laser Doppler velocimeters
Controlled terms:Nondestructive examination - Quality control - Technology
Author affiliation:1 College of Biosystem Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
Corresponding author:Ying, Y. (yingyb@zju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:246-255
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:There has been a series of significant advances and applications in terahertz (THz) technologies which processes perspectivity, safety and spectroscopic fingerprinting ability. The unique properties of THz waves make them become tools for non-destructive detection and application in the fields of defense, industry, semiconductor, communication, biological medicine, pharmaceutical, agro-products, food and etc. Firstly, the principle and feature of THz spectroscopy and imaging techniques were introduced. Then, the non-metallic material characterization and defect inspection in foam and fiber composites were stated. The recent application of THz in agro-products and food was introduced mainly. Finally, the technology difficulties and issues of the THz technologies were analyzed, and their development prospects in the non-destructive detection field were presented.
Author affiliation:1 State Key Lab. of Fluid Power Transmission and Control, Zhejiang University, Hangzhou 310027, China
Corresponding author:Xu, B. (bxu@zju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:279-285
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Traditional noise reduction method for axial piston pump by optimizing the transition area in the valve plate is based on specific structural parameters, which is of less meaning for valve plate design. The formation mechanism of the noise excitation sources of hydraulic noise and structural noise for axial piston pump was discussed. Then, aiming at elimination of the pressure overshoot in piston chamber, and control of the peak value and position of backflow into piston chamber, a forward design theory of distribution method with damping orifice and damping groove for axial piston pump was proposed. Finally, a valve plate was designed based on this design theory. The noise reduction effect of this valve plate was analyzed. Results showed that the application of this design method could reduce the flow ripple amplitude apparently and the pressure overshot could be almost eliminated. Because the structure of the damping groove was not appointed, this design theory can be used in the valve-plate design of different domestic axial piston pumps.
Author affiliation:1 School of Aerospace Engineering, Shenyang Aerospace University, Shenyang 110136, China
2 Department of Mechanical Engineering, Gunma University, Gunma 376-8515, Japan
Corresponding author:Chen, L. (cl_officer1981@hotmail.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:28-32 38
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The experiment of effect of CO2 dilution on combustion characteristics of H2-CO blended fuel by using a spark-ignition engine with fixed speed was carried out. The results showed that fast burning velocity of H2 offset its lower LHV, as a result, BMEP at each equivalent ratio kept almost constant. H2 substitution also benefited for thermal efficiency, engine stability, CO and NOx exhaust emissions. Suitable dilution hardly affected BMEP and thermal efficiency, but greatly reduced NOx emission. However, excess dilution induced to partial burn, which was bad for all these parameters of BMEP, thermal efficiency and CO emission.
Author affiliation:1 State Key Laboratory of Tribology, Tsinghua University, Beijing 100084, China
Corresponding author:Feng, P. (fengpf@tsinghua.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:269-273
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Nonuniform distribution characteristics of random points generated by Monte Carlo method in the workspace of parallel manipulators were discussed. Based on the density of distribution of the multiple random variable function, the relationship between Jacobian matrix and the probability density function of workspace points generated by Monte Carlo method was deduced, and the relationship between the probability density of the output space and the manipulability of the parallel manipulator was also constructed. The manipulability of a 2-DOF 5R parallel manipulator was analyzed based on the Monte Carlo method. According to the working mode of the robot, the input space was divided into four subspaces, and the inverse singularity occurred in the boundary among different subspaces was pointed out. Simulation experiment illustrated that the Monte Carlo method could work well for manipulability analysis of parallel manipulators.
Number of references:15
Main heading:Monte Carlo methods
Controlled terms:Jacobian matrices - Manipulators - Probability density function
Uncontrolled terms:Density of distribution - Inverse singularity - Manipulability - Manipulability analysis - Non-uniform distribution - Parallel manipulators - Probability densities - Variable functions
Author affiliation:1 College of Food Science and Nutritional Engineering, China Agricultural University, Beijing 100083, China
2 Food Quality and Safety Centre, COFCO Nutrition and Health Research Institute, Beijing 100020, China
3 Vegetable Research Center, Beijing Academy of Agriculture and Forestry Science, Beijing 100097, China
4 College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Han, D. (handh@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:174-178
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to achieve the fast and non-destructive detection of mini watermelon quality during growth process, the basic information collection methods for fruit measuring were analyzed quantitatively. The PLS modeling results showed that both the tissue water content and soluble solids content could obtain good results at the top position and the equator. The modeling performance had some differences with basic chemical information at different depths, but both the tissue water content and soluble solids content could got the best results in the middle information area which was under 2-3 cm from the rind. The correlation coefficients of tissue water content at the top location and the equator were 0.953 and 0.924, and the RMSEP were 0.510 and 0.766, respectively. The correlation coefficients of soluble solid content at the top location and the equator were 0.952 and 0.929, and the RMSEP were 0.666 and 0.732, respectively. For the mini Jingxiu watermelon, the best foundation information area for NIR detection was the middle area.
Number of references:11
Main heading:Water content
Controlled terms:Infrared devices - Tissue
Uncontrolled terms:Correlation coefficient - Information collections - Mini watermelon - Near Infrared - Nondestructive detection - Soluble solid content - Soluble solids content - Tissue water content
Classification code:444 Water Resources - 461.2 Biological Materials and Tissue Engineering - 741.3 Optical Devices and Systems
DOI:10.6041/j.issn.1000-1298.2013.07.030
Database:Compendex
26. Accession number: 20132916509651
Title: Agricultural products traceability method using uncertain data
Author affiliation:1 College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China
2 Yantai Academy, China Agricultural University, Yantai 264670, China
Corresponding author:Sun, R. (sunrz_cn@sina.com.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:154-159
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:For the existing traceability model could not express the mixing process quantitatively, the uncertain data were brought into traceability system and the model based on these uncertain data was built up. A traceability inquiry method using uncertain data was proposed. The multi-source tracing problem was solved by using basic representation and inquiry method of uncertain data. The functions of simple inquiry, node evaluation and single node abnormal deduction were achieved based on the proposed model and the solving method of multi-node abnormal deduction was presented.
Number of references:14
Main heading:Agricultural products
Uncontrolled terms:Inquiry methods - Model-based OPC - Solving method - Traceability methods - Traceability model - Traceability systems - Tracing problem - Uncertain datas
Classification code:821.4 Agricultural Products
DOI:10.6041/j.issn.1000-1298.2013.07.026
Database:Compendex
27. Accession number: 20132916509632
Title: Influence of injection temperature on atomization characteristics of biodiesel
Authors:Shi, Fuxi1 ; Chen, Jun1
Author affiliation:1 College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Chen, J. (chenjun_jdxy@nwsuaf.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:33-38
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to analyze the influence law of injection temperature on biodiesel atomization effect accurately, using self-designed high response thermocouple, the filled trough temperature variation of the soybean fatty acid methyl ester (SFAME) were measured under the rated conditions of S195 engine. In the common rail fuel injection system, the injection temperature under engine working condition was simulated. With the Malvin particle measuring instrument, the variation of droplet diameter distribution was measured under different injection temperatures. The experimental results showed that the injection temperature was 281°C at fuel injection beginning under the stable rated conditions of S195 engine, and presented a downtrend during the injection duration. With the control of heating device of oil supply line, the Sauter mean diameter (SMD) could be decreased by increasing the injection temperature, but increase trend of SMD was slow down with the increasing injection temperature. The preheating of biodiesel before injector will increase injection temperature in the spray process later and improve the atomization effect.
Uncontrolled terms:Atomization characteristics - Biodisel - Common rail fuel injection - Injection temperature - Measuring instruments - Sauter mean diameter (SMD) - Soybean fatty acids - Temperature variation
Classification code:521 Fuel Combustion and Flame Research - 523 Liquid Fuels - 612 Engines - 802.3 Chemical Operations - 804.1 Organic Compounds - 944.5 Temperature Measuring Instruments
DOI:10.6041/j.issn.1000-1298.2013.07.007
Database:Compendex
28. Accession number: 20132916509656
Title: Moisture content detection of paddy rice based on capacitance approach
Authors:Liu, Zhizhuang1 ; Lü, Guiyong1
Author affiliation:1 Electronics Research Institute, Hunan University of Science and Engineering, Yongzhou 425199, China
Corresponding author:Liu, Z. (liuzz168@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:179-182
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to quickly detect rice moisture content, a uniplanar capacitor probe was designed. A corresponding converting circuit was also designed for getting digital value of capacitance. The rice moisture content was converted into capacitance and digital value in turn by the capacitor probe and converting circuit. Finally, the rice moisture content was obtained by using single chip. After the calibration experiments and temperature characteristics experiments, the results showed that prediction error of moisture content was within ±0.8% at the range of rice moisture content of 8%-23%. With the temperature of 12-33°C and rice moisture content of 12.86%, the temperature shift value was 0.2%/°C.
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
2 State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, China Academy of Sciences, Yangling, Shaanxi 712100, China
Corresponding author:Lei, T. (leitingwu@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:73-77 72
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:A near infrared reflection (NIR) soil water sensor was developed for rapid measurement of soil moisture content. Light emitting diodes (LEDs), at 1940 nm and 1800 nm respectively, were used as measurement and reference light sources. The photodiode received the light reflected from the soil surface to produce an output electronic signal, which was related to the soil moisture content. The received signals were put into a two stage pre-amplifier, an analogue/digital (A/D) transfer, and then were displayed and stored. A certain relationship was found between the output reflected light and soil moisture content. The experiment results showed that the distance from light sensor to soil surface had some influences on the intensity of received signal. According to the sensor structure, a certain distance could be chosen to make a better intensity and stability of reflected signal. The reflectance of the two light sources decreased with increase of soil particle size. There was a strong linear correlation between the relative absorption depth and soil moisture content, and the determination coefficient was 0.863.
Author affiliation:1 Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
2 School of Construction Engineering, Anhui University of Technology, Maanshan 243002, China
Corresponding author:Yang, J. (jsyang@issas.ac.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:78-82 66
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Taking typical area of the Peacock River Basin as the study area, apparent electrical conductivity of soil was induced by using electromagnetic technology, and thus layered soil salinity interpreting models were built up. 3-D soil salt distribution was characterized by using 3-D ordinary Kriging method. The profile soil salt information was presented by different operation modes. The layered salinity interpreting models showed good accuracy. Soil salt distributions of different zones in this area were significantly different. Most of soil in study area belonged to moderate salinity, and some local areas were severe saline soil. Thus, the effective countermeasures should be taken to prevent and control soil salinization in this region.
Author affiliation:1 College of Mechanical Engineering, Jimei University, Xiamen 361021, China
2 Engineering Training Center, Jimei University, Xiamen 361021, China
Corresponding author:Li, Y. (ypli@jmu.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:286-292
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:By using fixed/floating coordinate system and the support function method, the instantaneous 1-D linear area and interval sets were proposed. The rise motion, return motion and whole motion interval sets were put forward. The basic principles of solving the allowable selected area of the flat-faced line and the allowable value range of the cam basic radius were proposed. The analytic formulae were derived. Then the analytical criterion of the solution existence and its existing form were obtained. The class II synthesis of disc cam mechanism with flat-faced follower in planar motion was resolved.
Number of references:20
Main heading:Cams
Uncontrolled terms:Analytic formula - Basic principles - Co-ordinate system - Disc cam mechanism - Flat-faced follower - Planar motion - Solution existence - Support functions
Classification code:601.3 Mechanisms
DOI:10.6041/j.issn.1000-1298.2013.07.049
Database:Compendex
32. Accession number: 20132916509634
Title: Experimental measurement on cavitation pattern at impeller inlet of centrifugal pump
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Wang, Y. (wylq@ujs.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:45-49
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to study the cavitation pattern at impeller inlet of centrifugal pump, a medium specific speed centrifugal pump was selected as an object, and a total transparent water tank was located at inlet pipeline of model pump. Based on pump product testing system and image acquisition system, the cavitation pattern at impeller inlet under three different conditions were measured on the centrifugal pump closed experimental rig. Experimental results showed that the vapors generated at suction side of blade near the leading edge at first, but the location varied with the operation condition. With the decrease of NPSHa, the vapors generated at plurality of blades. The generation, development and collapse process obviously appeared with the rotation of impeller. When the head dropped seriously, the distribution of the vapors hardly varied with the rotation of impeller, and the vapor volume fraction near impeller hub was less than that at shroud side.
Number of references:12
Main heading:Impellers
Controlled terms:Cavitation - Centrifugal pumps - Vapors - Water tanks
Author affiliation:1 College of Chemistry and Chemical Engineering, Xinxiang University, Xinxiang 453003, China
2 Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China
3 Institute of Oceanology and Marine Fisheries, Nantong 226007, China
Corresponding author:Wu, Z. (wuzb@ihb.ac.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:199-203
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:A theoretical model to evaluate total ammonia concentration in recirculating aquaculture system was established by investigating the relationship between impact factors of total ammonia. Subsequently, a system dynamics model for total ammonia in the recirculating aquaculture system was developed based on the theoretical model. The dynamics of total ammonia concentration in a culture pond during the breeding process was simulated by using STELLA simulation software. The simulation results were consistent with the measured values approximately, indicating that this model could simulate the experimental system to a certain extent and could provide suggestions on design and operation of the recirculating aquaculture system.
Number of references:20
Main heading:Ammonia
Controlled terms:Aquaculture - Computer simulation - Computer software - Lakes - System theory - Water quality
Uncontrolled terms:Ammonia concentrations - Design and operations - Experimental system - Recirculating aquaculture system - Simulation software - System Dynamics - System dynamics model - Water quality models
Classification code:961 Systems Science - 821.3 Agricultural Methods - 804.2 Inorganic Compounds - 723.5 Computer Applications - 723 Computer Software, Data Handling and Applications - 453.2 Water Pollution Control - 407 Maritime and Port Structures; Rivers and Other Waterways
DOI:10.6041/j.issn.1000-1298.2013.07.035
Database:Compendex
34. Accession number: 20132916509636
Title: Fluid-induced forces in centrifugal pump under given rotordynamic parameters
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Pan, Z. (pzy@ujs.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:55-60 66
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The effect of eccentricity and whirl frequency ratio on the internal and external characteristics of a centrifugal pump was investigated numerically and experimentally. Under a series of given rotordynamic parameters, the RNG k-Ε turbulence model was applied in the simulation of whole flow field including front and back shrouds of pump. The influence of eccentricity on the external characteristics of the centrifugal pump and the impact of whirl frequency ratio on the internal flow field were analyzed. Then the distribution of the fluid-induced forces in the centrifugal pump and the effect of eccentricity and whirl frequency ratio on the fluid-induced forces in the centrifugal pump were investigated. According to the results, it could be drawn that the high efficiency area of centrifugal pump narrows as the eccentricity increases. Normal fluid force component Fn and tangential fluid force component Ft were both approximate into a quadratic function relation against the whirl frequency ratio ω/Ω, influenced by the eccentricity. The fluid-induced forces acting on the impeller were mainly generated by the internal fluid of impeller and uneven circumferential pressure distribution inside. In the centrifugal pump, when ω/Ω>0, vortexes within the impeller were less, hydraulic loss was lower and so restrained the whirling motion; when ω/Ω<0, vortexes within the impeller were more, hydraulic loss was higher and thus promoted the whirling motion.
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Wang, K. (wangkai@ujs.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:61-66
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Slip velocity of impeller outlet for a double-blade centrifugal pump was studied with PIV technology and slip factors of six blade phases at the seven conditions were obtained. It is found that average slip factor at the six blade phases gradually decreased with the increase of flow rate. Flip factors of the double-blade centrifugal pump were calculated with Stodola formula, Weisner formula and Stechkin formula and all the results were compared with experimental values at the seven conditions. Weisner formula, whose calculation errors were the smallest, was corrected on the basis of experimental values. And a double-blade impeller was redesigned to verify correct formula. The results showed that the calculation errors of corrected slip factors at the seven conditions were less than 3.5% and the maximum error was 3.23%.
Author affiliation:1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China
2 Chinese Academy of Agricultural Mechanization Sciences, Beijing 100083, China
3 College of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 310036, China
Corresponding author:Pan, J. (panhouse@zju.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:204-209
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Great hazards could be easily caused by high concentrations of ammonia in chick houses, which are almost inclosed and heated up with low ventilation rate. A technology of in-situ unpowered biofiltration was studied to remove ammonia gas in chick houses. Analytical parameters included inorganic nitrogen compounds, pH value, and electrical conductivity (EC) of the superficial and inner media. Results of 37 d operation in synchronization with a whole circle for chick brooding showed that, in the superficial media, the maximum ammonia elimination capacity was higher than 4.03 g/kg, the maximum ammonium nitrogen absorption ability achieved 1.59 g/kg, the highest nitrate nitrogen content achieved 2.69 g/kg, and nitrite nitrogen content was nearly 0, pH value showed a decreasing trend in the range of 8.81-7.39, and EC kept increasing with the highest increment of 2.30 mS/cm. However, the contents of ammonium, nitrate and total inorganic nitrogen as well as EC in inner media were far lower than those in superficial media. It suggested that further work should be done towards optimization of media depth setting. In conclusion, in-situ unpowered biofilter exhibited high ammonia elimination capacity and could be applied for contaminated air degradation in chick houses.
Classification code:402.3 Residences - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 643.1 Space Heating - 801.1 Chemistry, General - 804 Chemical Products Generally - 804.2 Inorganic Compounds
DOI:10.6041/j.issn.1000-1298.2013.07.036
Database:Compendex
37. Accession number: 20132916509649
Title: Effect of different pretreatments on tribological properties of wheat straw/polypropylene composites
Author affiliation:1 College of Engineering, Nanjing Agricultural University, Nanjing 210031, China
2 Jiangsu Key Laboratory for Intelligent Agricultural Equipment, Nanjing 210031, China
Corresponding author:He, C. (chunxiahe@tom.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:138-143
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to improve the interfacial bonding strength of wheat straw fibers and polypropylene (PP), the wheat straw fibers were treated by combining treatment. The surfaces of fibers were pretreated by five methods, such as NaOH, soaked in acetic acid solution, hydrothermal treatment, steam explosion treatments and microwave treatment. Then, they were compounded with coupling agent treatment. The wheat straw/PP composites were prepared by melt blending and molding. The microstructure of wheat fibers after different surface treatments was observed by stereo microscope. The infrared spectroscopy of wheat straw fibers after different surface treatments was examined by Fourier transform infrared (FTIR) technology. The tribological properties of PP composites filled with different surface treated wheat straw fibers were investigated by using M-2000A abrasion testing machine. The results showed that NaOH, hydrothermal treatment and steam explosion treatments had significant impact on the chemical composition of wheat straw fiber. The tribological properties of PP composites filled with combined treated fibers excelled than that of the composites filled with coupling agent treated fibers. The main wear mechanisms of worn surfaces were abrasive wear and adhesive wear. It was found that the composites filled with hydrothermal treatment and steam explosion treatment had good tribological properties.
Classification code:951 Materials Science - 931.2 Physical Properties of Gases, Liquids and Solids - 931 Classical Physics; Quantum Theory; Relativity - 821.5 Agricultural Wastes - 817 Plastics and Other Polymers: Products and Applications - 815.1.1 Organic Polymers - 812 Ceramics, Refractories and Glass - 811 Cellulose, Paper and Wood Products - 803 Chemical Agents and Basic Industrial Chemicals - 802.3 Chemical Operations - 802 Chemical Apparatus and Plants; Unit Operations; Unit Processes - 539 Metals Corrosion and Protection; Metal Plating - 415 Metals, Plastics, Wood and Other Structural Materials
DOI:10.6041/j.issn.1000-1298.2013.07.024
Database:Compendex
38. Accession number: 20132916509635
Title: Numerical simulation of whole flow field for centrifugal pump with structured grid
Author affiliation:1 Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Yuan, S. (shouqiy@ujs.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:50-54 49
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The performance of centrifugal pump with whole flow field was analyzed by using CFD technique. The blocking strategies and mesh generation on domains of the pump were presented. Numerical simulation of whole flow field model and simple model in CFX for the pump was then carried out and the reason of the difference between two models was compared. It was verified that the cavity indeed had effects on simulation results. The whole flow field model showed a higher accuracy than the simple model, and the flow pattern of two models were also different. The relationship between the sub-flowrates through front cavity and the overall performance of the pump was evaluated. The simulation results of whole flow field model and the measured results were compared. The relative errors of the head and efficiency were 0.79% and 0.9% at the normal flow rate Qd, while they were 6.24% and 9.61% at 0.2Qd. The accuracy of numerical simulation should be improved at minimal flow point.
Author affiliation:1 Department of Mechanical Engineering, Academy of Armored Force Engineering, Beijing 100072, China
Corresponding author:Guo, M. (13820167243.happy@163.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:17-22
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Diesel engine quasi-dimensional model were corrected by test in plateau. The full-coupled working process simulation model with variable altitude adaptation on certain heavy-duty vehicle propulsion (diesel engine and auxiliary system) was set up. According to the quasi steady state flow uniformity resistance and heat transfer equations, air intaken system resistance model were established. Based on 1-D unsteady compressible fluid dynamics theory and heat transfer theory, the working model of fuel injection system was erected. Considering the effect of lubricating oil on heat transfer, the engine cooling system model was established. Auxiliary system model and the working process of the engine were coupled, that means, the boundary conditions was two-way delivered. Simulation model were verified by experiment. The results show that the power reduces by 45% and fuel consumption increases by 71% at maximum at 4500 m altitude under external characteristic working condition. The heat quantity of cooling liquid in heat-flux distribution increases by 48.6%. The temperature field of piston-cylinder sleeve-cylinder head raises apparently, the peak temperature increases by 85-91 K. The delivery lift of water pump drops by 3.9 m at most at 3700 m altitude. When the water flow grows up, the thermal load of cooling system raises.
Author affiliation:1 Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education, China Agricultural University, Beijing 100083, China
Corresponding author:Li, M. (limz@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:216-221
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:De-noising of near infrared image and nonlinear estimation of nitrogen content were carried out to cucumber leaves in greenhouse. Fruit cucumber Deitastar was chosen as the object. A CCD camera with special filters was used to collect cucumber leaves' images in different growth time. After eliminating noise of image with wavelet transform, the images were separated based on grey theory. Correlation analysis between nitrogen content and each kind of vegetation index of cucumbers was conducted, and t tests to those coefficients of correlation were executed. The result showed that CNDVI, GNDVI, NDVI and NDGI were significantly related to nitrogen content of cucumber leaves. The correlation coefficient between CNDVI and nitrogen content of cucumber leaves reached 0.67, and the correlation coefficients between GNDVI, NDGI, NDVI and nitrogen content of cucumber leaves were all higher than 0.50. LS-SVM algorithm was used to construct estimation models between vegetation indexes and nitrogen content and CNDVI, GNDVI, NDGI and NDVI were used as the input of the model. The R2 values of calibration and validation models were 0.825 and 0.728 respectively.
Author affiliation:1 School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China
Corresponding author:Feng, H. (fenghh@bit.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:1-5
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to achieve stable operation of the free-piston engine generator, the forces status on the free-piston of the working process were analyzed. The results showed that the operation of the free-piston engine generator could be seen as a single degree of freedom damping system with forced excitations. Combining the energy conservation principle of the working process, the matching between the structure parameters and the performance parameters of free-piston engine generator was studied. Some necessary qualifications to achieve stable operation of the free-piston engine generator were obtained through coupling analysis calculation by using an energy equilibrium method. The analysis conclusion was validated on a prototype by simulation. The results showed that the movement of free-piston could reach stable operation approximately, and the coupling analysis method proposed was reasonable.
Number of references:12
Main heading:Engine pistons
Controlled terms:Engines
Uncontrolled terms:Energy conservation principle - Energy equilibrium - Engine generator - Free piston - Performance parameters - Single degree of freedoms - Stable operation - Structure parameter
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
2 China Irrigation and Drainage Development Center, Beijing 100054, China
Corresponding author:Yan, H. (yanhj@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:127-132
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Based on the model of droplet dynamics and evaporation, the simulation method of droplet flight was put forward under the wind condition. Software of simulating sprinkler water distribution was developed by Visual Basic 6.0. With the radial water distribution data of single sprinkler, the software could simulate water distribution of single sprinkler or sprinkler irrigation system and calculate combined application rate, uniformity coefficient and evaporation loss rate of sprinkler irrigation system. Taking the sprinkler 9708A as example, radial water distribution of single sprinkler and water distribution of sprinkler irrigation system with the combined spacings of 14 m × 14 m and 14 m × 12 m were simulated and compared with the measured values under the pressures of 0.20, 0.25 and 0.30 MPa. The results showed that the simulated values of radial water distribution of single sprinkler had the same tendency as the measured values on the whole, the relative error between simulated and measured values of flow rate ranging from 0.83% to 8.01%, that of the uniformity coefficient (Cu) ranging from 0.44% to 7.77%, and the simulated evaporation loss rate ranging from 0.51% to 1.75%. Several cases of sprinkler water distribution with different combined spacing were compared by using the developed software and other software. The relative error of the simulated values of Cu varied from 0.11% to 2.44%.
Number of references:19
Main heading:Sprinkler systems (irrigation)
Controlled terms:Application programs - Computer software - Drop formation - Evaporation - Phase transitions - Visual BASIC - Water supply systems
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 821.1 Agricultural Machinery and Equipment - 802.3 Chemical Operations - 801.4 Physical Chemistry - 723.1.1 Computer Programming Languages - 723 Computer Software, Data Handling and Applications - 446.1 Water Supply Systems
DOI:10.6041/j.issn.1000-1298.2013.07.022
Database:Compendex
43. Accession number: 20132916509659
Title: Microbial growth kinetics model of tilapia under variable temperatures
Author affiliation:1 College of Engineering, China Agricultural University, Beijing 100083, China
2 College of Information and Electric Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Fu, Z. (fzt@cau.edu.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:194-198
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The microbial growth kinetics model at constant temperature was built up. The effect of variable temperature on microbial growth state was found. Then the recorded variable temperatures were processed. Microbial growth kinetics model combined with Baranyi model under variable temperatures was obtained. A simulation experiment was also carried out to validate the accuracy of model. The determination coefficient was 0.956, the root mean square error was 0.165, the deviation factor was 0.994, and the accuracy factor was 1.134. The results showed that the model was adaptive to predict the growth of microbiology in the actual cold chain logistics.
Number of references:15
Main heading:Computer simulation
Controlled terms:Kinetics - Mean square error - Microorganisms
Uncontrolled terms:Cold chain logistics - Constant temperature - Determination coefficients - Deviation factor - Microbial growth - Root mean square errors - Tilapia - Variable temperature
Classification code:461.9 Biology - 723.5 Computer Applications - 731.1 Control Systems - 931 Classical Physics; Quantum Theory; Relativity
DOI:10.6041/j.issn.1000-1298.2013.07.034
Database:Compendex
44. Accession number: 20132916509653
Title: Hyperspectral imaging detection of beef color under different storage time
Author affiliation:1 College of Mechanical and Electrical Engineering, Shihezi University, Shihezi 832003, China
2 Food College, Shihezi University, Shihezi 832003, China
Corresponding author:Yao, X. (yaoxuedong@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:165-169
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to explore the feasibility of hyperspectral imaging technique to estimate beef color parameters under different storage time and sampling positions, hyperspectral images of 82representative beef samples were acquired. Color parameters, including brightness (L*), redness (a*), yellowness (b*) and saturation (C*) were also determined. Their representative spectra were obtained by selecting regions of interest (ROIs). By comparing and choosing appropriate spectral regions and pretreatment methods, optimum partial least squares (PLS) calibration models of each beef color parameters were established and evaluated, respectively. As for L*, a*, b* and C*, the correlation coefficients of calibration were 0.80, 0.91, 0.91 and 0.93, and root mean square errors of calibration were 2.23, 1.18, 0.82 and 1.12, respectively. The correlation coefficients of prediction were 0.92, 0.88, 0.87 and 0.89, and root mean square errors of prediction were 1.66, 1.45, 0.80 and 1.27, respectively. The results showed that hyperspectral imaging technique could be used to rapidly and non-destructively analyze beef color parameters under different storage time and sampling positions.
Number of references:15
Main heading:Color
Controlled terms:Beef - Calibration - Imaging techniques - Least squares approximations - Mean square error - Meats - Spectroscopy
Author affiliation:1 School of Technology, Beijing Forestry University, Beijing 100083, China
Corresponding author:Wang, D. (wangdian1982@gmail.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:241-245
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to improve the measuring accuracy of tree's diameter at breast height (DBH) and decrease the working load, an algorithm for measuring tree's DBH was proposed by combining the optical triangular method, image processing and least square fitting. The algorithm was proposed based on a series of theory analysis, and the measuring system was built up. Five trees with different diameters at breast height were measured and calculated. The testing result showed that the optical triangular method had higher accuracy, the error was less than 22 mm, and the relative error was less than 5.5%.
Number of references:16
Main heading:Optical data processing
Controlled terms:Algorithms - Forestry - Image processing - Least squares approximations - Trees (mathematics)
Uncontrolled terms:Breast height - Diameter-at-breast heights - Diameters at breast heights - Least-square fitting - Measuring accuracy - Measuring algorithm - Measuring systems - Optical triangular method
Classification code:723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 741 Light, Optics and Optical Devices - 741.3 Optical Devices and Systems - 821.0 Woodlands and Forestry - 921 Mathematics
DOI:10.6041/j.issn.1000-1298.2013.07.042
Database:Compendex
46. Accession number: 20132916509646
Title: Test and evaluation on variable-rate irrigation sprinkler
Author affiliation:1 College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
2 Institute of Soil and Water Conservation, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Wu, P. (scipapers@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:121-126 112
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Variable-rate nozzle achieves range and flow synchronous control according to the spraying shape and spray volume requirements. It has important significance on the precision irrigation. The variable nozzle with fan-shaped hole and static vane regulator was studied. Hydraulic performance, such as irrigation distribution and irrigation uniformity of variable nozzle under different pressure conditions was analyzed. Comparing with the traditional round nozzle spray domain, influence of variable vane regulator on nozzle performance and sensitivity to the working pressure were studied. The results of double factors repeated test showed that the single nozzle control area of variable precision irrigation sprinkler was reduced by 15.4% than the traditional round nozzle. The sprinkler irrigation evenness was increased by 9.5%. The sprinkler irrigation intensity was reduced by 15.7%. The range was reduced by 5.9%. The spraying domain coefficients reached to 64.0%. Combination evenness variance analysis results showed that the regulator and pressure as well as the interaction between them had significant influence. The design of the variable modifiers needs to meet the performance of nozzle under different working pressure conditions.
Number of references:21
Main heading:Sprinkler systems (irrigation)
Controlled terms:Nozzle design - Spray nozzles - Water supply systems
Uncontrolled terms:Combination of uniformity - Hydraulic performance - Irrigation uniformity - Precision irrigation - Sprinkler irrigation - Test and evaluation - Variable rate - Water distributions
Classification code:446.1 Water Supply Systems - 631.1 Fluid Flow, General - 821.1 Agricultural Machinery and Equipment
DOI:10.6041/j.issn.1000-1298.2013.07.021
Database:Compendex
47. Accession number: 20132916509658
Title: Isolation and identification of Alicyclobacillus from Shaanxi apple libraries
Author affiliation:1 College of Food Science and Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
Corresponding author:Yue, T. (yuetl@nwsuaf.cn)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:187-193
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:In order to make sure the distribution of Alicyclobacillus from apple libraries in Shaanxi province, the Alicyclobacillus in apple and air were isolated and purified by using acidified AAM medium. The cell morphology, colony morphology, growing conditions, cultural characteristics and physiological characteristics were compared with the reference strain A. acidoterrestris DSM3922T. A phylogenetic tree based on 16S rDNA sequence analysis was constructed. The genetic location of eight isolated strains was clear. The isolated strain LC-4 was basically consistent with the reference stain Alicyclobacillus acidoterrestris DSM3922T in morphology and physiological characteristics. By 16S rDNA sequence analysis, isolated strain LC-4 shared a homology of 99% with the reference strain, so it belonged to A. acidoterrestris and the other seven strains belonged to Bacillus ginsengihuimi. The results suggested Alicyclobacillus was distributed in orchard soil, which might pose a threat to the quality of fruit juice, and needed to be controlled.
Author affiliation:1 College of Forestry, Beijing Forestry University, Beijing 100083, China
2 Beijing Institute of Surveying and Mapping, Beijing 100038, China
Corresponding author:Feng, Z. (fengzhongke@126.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:235-240
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:The tree crown volume is difficult to measure and calculate because of its irregular shape. A calculating method of tree crown volume, named voxel simulation method, was presented based on 3-D laser scanning point clouds data. The main idea of this method was to use a certain size of voxel to estimate tree crown. Firstly, tree crown was cut into segments with a k step-length along tree height. For each segments, all the points were projected to a plane that perpendicular to tree height. Subsequently, the plane was divided into pixels with size of k×k. The effectiveness of each pixel depend on whether there were points projected in it. Then the effective pixels were counted and recorded as T. Finally, formula T×k×k×k was used to calculate the tree crown volume. When the k was equal to a tenth of crown diameter, the calculated crown volume was tending to stability. This algorithm did not need to consider the crown shapes of different tree species, which could reduce human's subjective factor influence. It could be used to calculate tree crown volume based on 3-D laser scanning technology.
Author affiliation:1 College of Water Resources and Architectural Engineering, Northwest A and F University, Yangling, Shaanxi 712100, China
2 National Laboratory for Agriculture and the Environment, USDA-ARS, Ames IA 50011-3120, United States
3 Department of Agronomy, Iowa State University, Ames IA 50011, United States
Corresponding author:Ma, X. (x36936@gmail.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:67-72
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Soil dielectric property is an important physical parameter affecting the measuring accuracy and adaptation of moisture content by using FDR sensor. In order to obtain the best frequency of 7-probes FDR with length of 28 mm and needle-to-needle spacing of 10 mm, scattering parameters of LF-UHF wave bands (1 MHz-3 GHz) in four kinds of soil were measured by using VNA. Though transformation based on Logsdon model and Laird model, four soil apparent dielectric permittivities were calculated and figured in Matlab. The mechanism of soil polarization was analyzed by soil dielectric spectrum analysis. The relationship between soil dielectric property and frequency was discussed. The working frequency of 44-398 MHz for FDR sensor was confirmed. Taking temperature into consideration, the ideal working frequency band was 62-110 MHz in which 75 MHz was the best. The soil dielectric value was only sensitive to soil moisture content under the best frequency. It was the ideal frequency for eliminating the effect of temperature and other factors on FDR sensor.
Author affiliation:1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
2 Faculty of Agriculture and Environment, The University of Sydney, Sydney 2006, Australia
Corresponding author:Tang, Z. (tangzejun@sina.com)
Source title:Nongye Jixie Xuebao/Transactions of the Chinese Society for Agricultural Machinery
Abbreviated source title:Nongye Jixie Xuebao
Volume:44
Issue:7
Issue date:July 2013
Publication year:2013
Pages:83-89
Language:Chinese
ISSN:10001298
CODEN:NUYCA3
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Machinery, No. 1 Beishatan Deshengmen Wai, Beijing, 100083, China
Abstract:Polyacrylamide (PAM) was added to fly ash to amend sandy soil. The migration of heavy metals, such as Cr, As and Ni in soil-plant system and the influence of PAM on it were investigated, respectively. The experimental design included three PAM application rates (0, 60 mg/kg and 120 mg/kg) and four fly ash application rates (0, 5%, 10% and 15%). The treatment without fly ash and PAM was prepared as a control. The results showed that the addition of fly ash increased the concentrations of Cr and Ni in the surface sandy soil, while there was a decline in As concentration at high fly ash application rates (15%). The addition of PAM could stabilize a large quantity of heavy metals within topsoil to control their leaching risk as well as reduce the amounts of Cr, As and Ni absorbed by corn.