2013年12月第29卷第24期

2013年12月第29卷第24期

Accession number:20140517248502
Title:Effects of flight altitude and speed of unmanned helicopter on spray deposition uniform
Authors:Qiu, Baijing (1); Wang, Liwei (1); Cai, Donglin (2); Wu, Jianhao (2); Ding, Guorong (2); Guan, Xianping (1)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education and Jiangsu Province, Jiangsu University, Zhenjiang 212013, China; (2) Station for Popularizing Agricultural Machinery Technique Zhangjiagang City, Zhangjiagang 215611, China
Corresponding author:Qiu, B.(qbj@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:25-32
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to find out the factors and degree of influence affecting small unmanned helicopter spray deposition, and formulate the corresponding test methods and specifications through experimental results, this paper studied the relationship between spray deposition characteristics and flight height, flight velocity of an unmanned helicopter and the interaction between two factors, and arranged a test by a second factor three level test. An experiment was conducted with a diameter of 90 mm glass sample dish as collecting droplets sampling tools, setting up six sampling points, with the interval of sampling being 5 m, and each sample dish was placed on the top of wheat, about 0.8 m. Then 10 mL of distilled water was added in the sample plate in advance as a sample base to collect settlement droplets in the spray test. A 4 g/L carmine solution was selected as medium for spraying, monitored wind speed of flight direction refer to meteorological station monitoring method in spraying test, at the same time, monitored humidity and temperature. Then t the collected samples were measured by UV-2102 PCS type ultraviolet visible spectrophotometer, first, scan absorption wavelength of carmine solution, selecting = 508 nm as the measurement wavelength to measure absorbance. Secondly, a carmine standard solution was prepared in 0, 0.025, 0.05, 0.075 and 0.1 g/L to establish a mathematical model of concentration and absorbance and convert concentration into absorbance under the established wavelength, and convert taken samples measurement results into concentration according to the mathematical model. Finally, absorbance of taken samples were converted into mass concentration, that is a quality of carmine per square centimeter as the experimental results for data analysis. Next, the significance level α = 0.05 was selected. The average concentration and the coefficient of variation to variance and regression analysis was selected to study the degree of effect of unmanned helicopter flight velocity, flight height, and interaction of these two factors to deposition concentration and deposition uniform. The analysis results showed that: flight height, flight velocity of unmanned helicopter, and the interaction between these two factors have a very significant impact on the deposition concentration, the respective P-value values is 2.0684×10-4, 8.2190×10-5 and 9.7052×10-5; flight height, flight velocity of an unmanned helicopter has a very significant impact on the deposition uniformity, the respective P-value values are 9.8410×10-3 and 1.1550×10-3; the interaction between the two factors have a significant impact on the deposition uniformity, and the P-value values are 2.5594×10-2. The model established respectively between deposition concentration, deposition uniformity and flight height, flight velocity, in interval range of the flight velocity and flight height was not significant, and the respective regression equation lost to test is FLf=3.7024<F0.1 (3, 1) =53.5932, FLf=17.60<F0. 1 (3, 1) =53.5932. These results can provide guidance for the actual production application. Therefore, the factors affecting deposition and uniformity are: flight altitude, flight speed, and the interaction between the two factors. The model established respectively between deposition concentration, deposition uniformity and flight height, and flight velocity can provide guidance for the actual production application.
Number of references:27
Main heading:Helicopters
Controlled terms:Deposits - Drops - Experiments - Mathematical models - Quality control - Regression analysis - Spraying - Testing - Unmanned aerial vehicles (UAV)
Uncontrolled terms:Absorption wavelengths - Coefficient of variation - Flight height - Flight velocity - Humidity and temperatures - Meteorological station - Small unmanned helicopters - Ultraviolet visible spectrophotometer
Classification code:921 Mathematics - 913.3 Quality Assurance and Control - 901.3 Engineering Research - 813.1 Coating Techniques - 652.4 Helicopters - 922.2 Mathematical Statistics - 652.1 Aircraft, General - 612 Engines - 532 Metallurgical Furnaces - 443.1 Atmospheric Properties - 423.2 Non Mechanical Properties of Building Materials: Test Methods - 617 Turbines and Steam Turbines
DOI:10.3969/j.issn.1002-6819.2013.24.004
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248532
Title:Performance improving design on cloud computing for agricultural products safety traceability system
Authors:Chen, Liancheng (1); Hu, Yueming (1); Zhang, Feiyang (1); Duan, Wenjie (1); Yu, Pingxiang (1)
Author affiliation:(1) College of Information, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Hu, Y.(ymhu@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:268-274
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Information collection of the production, supply and marketing chain in agriculture is an absolutely necessary part in the driving process of construction of agricultural informationization. As a new technique in collecting information, and relying on its low cost, low power consumption and wireless transmission, a Wireless Sensor Network (WSN) has already permeated into the agriculture area. For an agricultural information system which employs a wireless sensor as its collection terminal, there is no doubt that the uninterrupted process for information collection, transmission, and storage, as well as inquiries from a large number of users, puts so much pressure on the system server, resulting in a low speed for web access and inquiry. The response time and response rate when visiting a web site are key points of a web site's performance. A supporting platform that has the capacity of mass storage and dealing with high concurrency traffic, therefore, is necessary for a Safety Tracing System for Agricultural Products. A cloud computing platform has an ability of cooperative working with multiple servers, and is able to share the load pressure caused by dealing with mass storage and high concurrency traffic. Following the agricultural Internet of Things, it is necessary to introduce a cloud computing platform to agriculture. The research group has undertaken 13 projects assigned from Science and Technology Department of Guangdong along with Economy and Information Commission in the past two years, including breeding safety, tracing, and electronic business for agricultural products. In order to meet the demand from the Economy and Information Commission, different platforms will be combined into one-Safety Tracing and Trade Platform for Agricultural Products. Recently, the research team has paid attention to setting up the Safety Tracing Platform on the basis of the breeding Internet of Things, dealing with some agricultural products like chickens, rabbits, fish, flocks, and herds. As a result of there being so many kinds of products and mass data required, it is quite necessary to bring a cloud computing platform into this system. It can raise the response rate of visiting a web site and improve the visiting performance by using a cloud computing technique that has a good performance on high storage and heavy load processing. A Safety Tracing System for Agricultural Products based on a cloud computing platform has been designed, and the performance of a system web site has been promoted. Based on a cloud computing platform, the Safety Tracing System for Agricultural Products described in this paper can be divided into three sub-systems logically-a cloud computing platform, a Safety Tracing Subsystem for Agricultural Products, and an Information Collection Subsystem in a WSN environment which is installed in a Zhuhai Production Base. The Bingo cloud platform based on Amazon EC2 was used to develop a private cloud in a cloud computing platform. The SQL Server database and NET language were used to develop a Safety Tracing Subsystem for Agricultural Products. WSN was adopted in an Information Collection Subsystem to collect indicators like temperature, PH value, and humidity during the production. As the first step of the project, the cloud computing platform was constructed, the Safety Tracing Subsystem for Agricultural Products was put onto the platform, and the Wireless Sensor Acquisition Subsystem was connected with the platform, and the construction of the Safety Tracing Subsystem for Agricultural Products based on a cloud computing platform has been finished so far. Secondly, a search algorithm called Hill-Climbing was used to optimize the Safety Tracing Subsystem for Agricultural Products based on a cloud computing platform. Then, to deal with mass data, Mapreduce was used for concurrent processing. The map function receives data and outputs key-value pairs as the middle output after processing. The output from the map function was processed by the Mapreduce framework before being sent to the reduce function. This processing sorts and groups the key-value pairs by keys. Then the reduce functions receive the pairs with the same key and give the final output. This is the advantage of cloud computing: a mass data is cut up into pieces and are passed to CPUs for concurrent processing, which improves the performance of the system on the cloud platform. Here is how the system works: wireless sensor transmits the data of the field information collected from a locale to the cloud database. The cloud computing platform will automatically assign the storage to the data. When customers trace the product information, the platform will automatically balance the tasks of information querying with high traffic and heavy load, making several servers working cooperatively so that it can return the information to customers quickly. Besides, the platform also can use Mapreduce to cut up a mass data into pieces for many CPUs to process concurrently. Research on the heavy load processing performance of cloud computing platform when dealing with storing mass data and high traffic was conducted and the response time of dealing with high traffic based on the platform were described in this paper. The capacity of processing by sharing the heavy load also examined. By comparing the capacity of the cloud computing platform server with that of a general server, the results indicated that there is an all around advance after carrying the system from a general server to a cloud computing server. The response rate of visiting a web site was raised by 33%.
Number of references:30
Main heading:Cloud computing
Controlled terms:Agricultural products - Commerce - Design - Digital storage - Internet - Product design - Program processors - Query processing - Research - Resource allocation - Response time (computer systems) - Sensors - Surveys - Websites - Wireless sensor networks
Uncontrolled terms:Agricultural information systems - Aquatic products - Cloud computing platforms - Information collections - Internet of Things (IOT) - Science and Technology - Trace - Wireless transmissions
Classification code:913.1 Production Engineering - 723 Computer Software, Data Handling and Applications - 801 Chemistry - 821.4 Agricultural Products - 901.3 Engineering Research - 911.2 Industrial Economics - 912.3 Operations Research - 722.4 Digital Computers and Systems - 718 Telephone Systems and Related Technologies; Line Communications - 717 Optical Communication - 716 Telecommunication; Radar, Radio and Television - 408 Structural Design - 405.3 Surveying - 722.1 Data Storage, Equipment and Techniques
DOI:10.3969/j.issn.1002-6819.2013.24.035
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248530
Title:Land consolidation strategies in Huang-Huai-Hai Plain based on man-earth relationship
Authors:Hong, Shuman (1); Hao, Jinmin (1); Ai, Dong (1); Yang, Li (3); Zhou, Ning (1); Meng, Peng (1)
Author affiliation:(1) College of Resources Environmental Sciences, China Agricultural University, Beijing 100193, China; (2) Key Laboratory for Agricultural Land Qulity Monitoring and Control, The Ministry of Land and Resources, Beijing 100193, China; (3) School of Public Policy and Management, Tsinghua University, Beijing 100084, China; (4) China Institute for Rural Studies, Tsinghua University, Beijing 100084, China
Corresponding author:Hao, J.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:251-259
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The change in the needs of human development produces new requirements on the land-use environment. The contradictions of the man and earth relationship are significant. Land consolidation improves and controls the land-use environment through artificial means for satisfying the needs of human development. It is an important means for optimizing the land-use system and coordinating the man-earth relationship. However, there are few reports about land consolidation from the point of view of the man-earth relationship. With the rapid development of urbanization and industrialization, the conflicts of land supply and demand are significant in the Huang-Huai-Hai Plain. This conflict must be solved by optimizing land-use overall, so the beginning of land consolidation is very necessary in the Huang-Huai-Hai Plain. In order to instruct land consolidation and coordinate the man-earth relationship, this paper took the 311 counties in the area around Huang-Huai-Hai Plain as research units, and proposed a classification model for the coordinated developmental of the man-earth relationship on the evaluation index system. First, based on the human activity and land-use environment, this paper established an evaluation index system of the man-earth relationship. 18 factors of the evaluation index system were selected from the population distribution, population migration, production environment, livelihood environment, domestic environment, and ecological environment. Then, the entropy method was employed to attach weight to the factors, and computed the total values of counties through the weight. Finally, the coordinated developmental model was employed to calculate the evaluation values of counties on the basis of total values. According to the evaluation values, the classification of land consolidation in the Huang-Huai-Hai Plain was divided into four types, including the optimal consolidation type, the prior consolidation type, the key consolidation type, and the moderate consolidation type. Meanwhile, the land consolidation strategies in the Huang-Huai-Hai Plain were proposed, based on the result of classification and the meaning of land consolidation. For optimal consolidation, its coordinated developmental degree was between 0.60 and 0.80.It was the classification of good coordination development, its suitable consolidation strategy was focused on consolidating construction land, and optimizing the livelihood environment, domestic environment, and the ecological environment. For prior consolidation, its coordinated developmental degree was between 0.40 and 0.60. It was the classification of marginal coordination development, its suitable consolidation strategy was focused on consolidating construction land in the urbanization leading model and coordinating the production environment and the livelihood environment. For key consolidation, its coordinated developmental degree was between 0.20 and 0.40.It was the classification of light disorder and recession, and its suitable consolidation strategy was focused on consolidating the village and agricultural land, and coordinating the production environment and the domestic environment. For moderate consolidation, its coordinated developmental degree was between 0 and 0.20.It was the classification of serious disorder and recession, and its suitable consolidation strategy was focused on consolidating the agricultural land and improving the production environment. For the first time, this paper quantified the human needs and analyzed land consolidation strategies from the point of the man-earth relationship. The results were in accord with local conditions, and offered theoretical support for the land consolidation planning of the Huang-Huai-Hai Plain. However, there were some limitations. First, the research area was plain, ignoring the terrain and geologic structure. If this research is applied in other areas, the addition of factors about terrain and geologic structure will be very important. Second, the policy factor and the will of the people played a great influence on land consolidation. Therefore, they should be considered in the planning of land consolidation in reality. Additionally,, the data of the Huang-Huai-Hai Plain was updated in 2008, and this affected the meaning of the practice research in time.
Number of references:29
Main heading:Landforms
Controlled terms:Consolidation - Ecology - Economics - Land use - Models - Optimization - Planning - Population dynamics - Research
Uncontrolled terms:Coordination development - Development degree - Evaluation index system - Huang-Huai-Hai Plain - Land consolidation planning - Man-earth relationship - Production environments - Strategy
Classification code:921.5 Optimization Techniques - 902.1 Engineering Graphics - 901.3 Engineering Research - 971 Social Sciences - 483 Soil Mechanics and Foundations - 454.3 Ecology and Ecosystems - 403 Urban and Regional Planning and Development - 481.1 Geology
DOI:10.3969/j.issn.1002-6819.2013.24.033
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248501
Title:Law of spatial airflow velocity distribution for wide-swath air-blast sprayer
Authors:Song, Shuran (1); Hong, Tiansheng (1); Liu, Hongshan (3); Ruan, Yaocan (3); Chen, Jianze (3)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, Guangzhou 510642, China; (2) Division of Citrus Machinery, China Agriculture Research System, Guangzhou 510642, China; (3) College of Engineering, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Hong, T.(tshong@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:17-24
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Spraying droplet adhesion and deposition were affected by the external flow field distribution of the air-blast sprayer. The swath of an air-blast sprayer can be expanded through expanding the duct and elongating rectangular outlet. In this paper, a wide-swath air-blast sprayer was applied as the experimental platform and its external airflow velocity field was tested. The duct of the wide-swath air-blast sprayer used in the experiment was made up of a cylindrical segment, a contractive segment, and an expanding segment. An axial fan was installed inside the cylindrical segment, and there were a semi-elliptical fluid director and distributors in the contractive segment. One end of the expanding segment was connected with contractive segment and the other was a rectangle outlet. The long side of the rectangle outlet was vertical to the ground and the axis of the duct was parallel to the ground simultaneously when testing was conducted. The airflow speed field of the wide-swath air-blast sprayer was tested indoors. The airflow speed sampling points were located with a sampling frame made up of lattices (11×11 cm), and the airflow speed field and spray swath were tested in cross-sections 1m, 1.5 m, 2 m, and 2.5 m away from the outlet. The average of ten testing wind speeds at each sample point was taken as the final speed of that point. The free turbulent jet theory was applied for data analysis. The distribution and variation mechanism of the wide-swath air-blast sprayer airflow velocity were obtained. The experimental results indicated that the relationship between the axial longitudinal time-averaged wind speed and the air blast distance of the wide-swath air-blast sprayer took on an attenuated power function with the fan power supply in different frequencies. The axial longitudinal time-averaged wind speed was in line with the attenuated power function regular pattern to which the axial longitudinal speed of the three-dimensional free turbulent jet was submitted. The relationship between swath and air blast distance of the wide-swath air-blast sprayer presented a linear direction. According to the experimental data, the jet boundary curves were regressed. The top boundary curve and the bottom boundary curve of the jet along the outlet's long axis was not the same, as there was a vortex structure between the jet and the ground. The "virtual source, " a point at which the top boundary and the bottom boundary intersected was not on the horizontal axis of the duct. The angle between the top boundary and the horizontal axis of the duct was 20.5°, while the angle between bottom boundary and the horizontal axis was 28.8°. Meanwhile, it was found that the two boundaries of the jet along the outlet's short axis were in keeping with the same regular pattern. The "virtual source, " a point at which two boundaries intersected was on the horizontal axis of the duct, and the angles between the two boundaries and the horizontal axis of the duct were approximately 4.18° and 4.23° respectively. At cross-sections 0.5 m, 1 m, 1.5 m, 2 m, and 2.5 m distances away from the duct outlet, the distributions along the outlet's short axis direction of the axial wind speed were similar. However, the distributions were not similar along the long axis direction. After a three-dimensional surface of airflow velocity field was reconstructed, two peaks of wind speed appeared along the long axis direction inside the boundary layer.
Number of references:29
Main heading:Air
Controlled terms:Agricultural machinery - Ducts - Fans - Jets - Spraying - Three dimensional - Velocity - Wind
Uncontrolled terms:Air-blast - Experimental platform - External flow fields - Three-dimensional surface - Variation mechanisms - Wide-swath - Wind field - Wind speed
Classification code:931.1 Mechanics - 902.1 Engineering Graphics - 821.1 Agricultural Machinery and Equipment - 813.1 Coating Techniques - 804 Chemical Products Generally - 641.2 Heat Transfer - 631.1 Fluid Flow, General - 618.3 Blowers and Fans - 443.1 Atmospheric Properties
DOI:10.3969/j.issn.1002-6819.2013.24.003
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248527
Title:Comprehensive evaluation of co-composting fermentation effect of biogas residue mixed with livestock manure
Authors:Song, Caihong (1); Jia, Xuan (1); Li, Mingxiao (1); Zhu, Chaowei (1); Yu, Yanbo (3); Wei, Zimin (2); Pan, Hongwei (1)
Author affiliation:(1) State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012, China; (2) College of Life Science, Northeast Agricultural University, Harbin 150030, China; (3) Rushan Forestry Bureau, Rushan 264500, China
Corresponding author:Li, M.(limingxiao8122@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:227-234
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In general biogas residue, along with livestock and poultry manure and straw as raw material, is not suitable for composting alone. Because it is mainly composed of cellulose and contains less readily biodegradable organic matter. The biogas residue mixed with livestock and poultry manure co-composting has two advantages. Firstly, the biogas residue fermentation is driven by easily degradable organic matter in manure. Secondly, the biogas residue is used as a conditioning agent during the composting, which is conducive to ventilation. A variety of comprehensive evaluation methods have been used for evaluating the compost maturity, but lack of study on the biogas residue mixed with livestock and poultry manure co-composting. In this study, four biogas residues mixed with pig manure and chicken manure co-composting experiments, with different material ratios (dry weight), were tested for amount of biogas residue, pig manure, and chicken manure using orthogonal experiment design. Physical (e. g. time required to reach 50°C, heating rate, duration time above 50°C, maximum temperature), chemical (e. g. pH value, organic matter, C/N, NH<inf>4</inf> -N, NH<inf>4</inf> -N/NO<inf>3</inf>--N, total nutrient) and biological (e. g. faecal coliform value and GI) indicators were characterized during composting. Correlation analysis among all above-mentioned indicators was conducted in order to determining the fermentation effect of biogas residue mixed with livestock and poultry manure co-composting more accurately,. A compost maturity evaluation index systemincluded pH value, duration time above 50°C, T value, NH<inf>4</inf> -N, NH<inf>4</inf> -N/NO<inf>3</inf>--N and GI after eliminating parameter overlap influnce. The fermentation effect of co-composting was evaluated using fuzzy comprehensive evaluation method, gray correlation analysis method and attribute recognition methodin order to provide a theoretical basis for biogas residue mixed with livestock and poultry manure compost utilized as fertilizer. The results showed that T3 (w (biogas residue amount): w (pig manure amount): w (chicken manure amount) =5.85: 8.49: 8.19), reaching the highest heating rate, the longest high temperature phase and the highest temperature in high temperature phase. T2 (5.85: 7.425: 6.825), was the second, T1 (7.02: 7.425: 8.19) and T4 (7.02: 8.49: 6.825) were the worst. The fermentation effect of T2 and T3 is better T1 and T4 based on the results of chemical indexes, such as pH, organic matter, C/N, NH<inf>4</inf> -N, NH<inf>4</inf> -N/NO<inf>3</inf>--N and total nutrient content. End facal coliform value of T1, T2, T3 and T4 was 1, 10-1, 10-2 and 1, respectively. GI of the four composting was 96.72%, 103.35%, 98.42% and 85.13%, respectively. Fermentation effects of T1, T2 and T3 were the same by fuzzy comprehensive evaluation method, gray correlation analysis method and attribute recognition method except T4. Better mature, better maturity reached for primary maturity and badly immature. In summary, the evaluation of compost fermentation effect should synthetically consider physical, chemical and biological indicators instead of a single index. Compared to other two methods, gray correlation analysis method is better suited for evaluating compost fermentation effect.
Number of references:31
Main heading:Agriculture
Controlled terms:Animals - Biogas - Biogeochemistry - Biological materials - Composting - Correlation methods - Experiments - Fermentation - Fertilizers - Heating rate - Manures - Organic compounds - pH
Uncontrolled terms:Biodegradable organic matter - Biogas residues - Chemical and biologicals - Comprehensive evaluation - Fuzzy comprehensive evaluation method - Gray correlation analysis methods - Maturity - Orthogonal experiment design
Classification code:922.2 Mathematical Statistics - 801.2 Biochemistry - 804 Chemical Products Generally - 804.1 Organic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes - 901.3 Engineering Research - 801.1 Chemistry, General - 522 Gas Fuels - 461.8 Biotechnology - 461.2 Biological Materials and Tissue Engineering - 452.3 Industrial Wastes - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 641.2 Heat Transfer
DOI:10.3969/j.issn.1002-6819.2013.24.030
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248505
Title:Elasto-statics analysis of spider reducer with small tooth number difference
Authors:Zhang, Jun (1); Xie, Shenglong (1); Xu, Peimin (1); Tong, Baohong (1)
Author affiliation:(1) School of Mechanical Engineering, Anhui University of Technology, Ma'anshan, 243032, China
Corresponding author:Zhang, J.(zhang_jun@tju.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:49-55
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:As a novel internal planetary gearing with small tooth number difference, the spider reducer has been found its wide applications in many industrial fields such as energy, mining, electricity and irrigation. Despite its successful applications for decades, the mechanical mechanism of the spider reducer has been rarely investigated. The reason for less investigations of the spider reducer may lie in two aspects. One is the complexity of the reducer's structure and the other is the property of over-constraints in the transmission. The lack of in-depth understanding of system's mechanics results in the premature fatigue of planetary bearings and severe vibrations in some application occasions. In order to obtain a fully understanding of the mechanics principle of this kind of transmission, this paper presents an elasto-static model for the spider reducer by using the method of sub-structure synthesis. With consideration for the structural features of the spider reducer, the overall transmission system is divided into three sub-systems, i. e., the spider gear sub-system, the spider shaft sub-system and the output shaft system. The static equilibrium equations of each sub-system are derived based on Newtonian theory. Since the transmission system is over constrained, some compatibilities are required. Thus, the deformation compatibility conditions for the spider reducer are then derived by analyzing the relationships between the deflections of different component. The considered deflections include those of internal gearings, planetary bearings as well as torsional deformations of spider and output shafts. With the proposed compatibility conditions, the equations of each sub-system are assembled and the global elasto-static governing equations are obtained. By solving the elasto-static governing equations, the static responses on each component in a working cycle can be simulated numerically. The static loads of internal gearings, the planetary bearings and the torques on crank shafts during one cycle are depicted. The simulation results indicate that the meshing forces of internal gearings in two parallel phases change periodically. The two phases of meshing forces share the same variation rules but there exists a 180 degree of phase angle difference. This is coincident with the structural symmetry of the spider reducer whose two parallel phases of mechanism are 180 degree configured. The fluctuations of meshing force curves are very small, which implies that the meshing procedure of the internal gearings in the spider reducer is quite stable. This is agreeable with the long service span of internal gearing in this kind of transmission. On the contrary, the simulations reveal that the load conditions on planetary bearings are quite severe. To be specific, the planetary bearings on input shaft demonstrate high load amplitudes while the planetary bearings on spider shafts come through a remarkable fluctuation during a working cycle. Both the high load amplitudes and the fierce variation shorten the service life of planetary bearings. This gives an explicit explanation for the premature fatigue of planetary bearings in application occasions. The elasto-static analysis of the spider reducer indicates that the dimensions of internal gearings and planetary bearings are open to optimization during the design stage in order to extend serve span of planetary bearings and achieve better transmission performances.
Number of references:23
Main heading:Gears
Controlled terms:Deformation - Machinery - Models - Static analysis - Wheels
Uncontrolled terms:Compatibility conditions - Deformation compatibility - Phase angle differences - Spider reducer - Static equilibrium equations - Tooth number - Torsional deformations - Transmission performance
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 601 Mechanical Design - 601.2 Machine Components - 723.1 Computer Programming - 902.1 Engineering Graphics
DOI:10.3969/j.issn.1002-6819.2013.24.007
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248503
Title:Modeling and experiment on rotary extrusion torque in ring-die pelleting process
Authors:Wu, Kai (1); Sun, Yu (1); Peng, Binbin (1); Ding, Wuxue (1); Wang, Shuanhu (1)
Author affiliation:(1) School of Mechanical Engineering, Nanjing University of Science and Technology, Nanjing 210094, China
Corresponding author:Wu, K.(wukai@mail.njust.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:33-39
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Rotary roll extrusion pelleting technology is a kind of mainstream technology in the area of pellet forming technology, and the pellet mill has been widely used in the biomass-energy industry, feed industry, chemical industry, pharmacy, and so on. The pellet produced by the pellet mill has many advantages, such as a high forming rate, high absorption rate, high calorific value, and low pollution. But because of absence of the torque modeling theory, the existing pelleting technology with high consumption, low productivity, and low service life has been the bottleneck of industrial development. By a mathematical analysis, FEA simulation, and testing research, this paper aimed at developing an accurate torque model in the pelleting process of rotated roll forming. First, based on the unit force analysis and generalized Hooke law, the pressure distribution model along the die hole was founded. Then based on the DPC model and rolling processes, the FEA model of the pelleting process was created, and the stress distribution in the compacted zone was analyzed. Next, based on the results of the FEA, the pressure distribution in the compacting zone was set as aquadratic curve, and the pressure models in the compacting zone and extruding zone were built. Finally, the torque model in the ring-die pelleting process was developed. The experiments were designed to verify the model created, and the wireless torque testing system was used to analysis the torque datum. In order to eliminate the effect of the bending moment of the belt in pelleting process, two strain foils were stuck symmetrically along the same circumference of a shaft. The experimental material was chicken feed and the main components included Zea mays, wheat, bean, fish flour, bone flour, salt, and so on. The structural parameters of the pellet mill were as follows: the ring die radius was 175 mm, the number of rollers was 2, the ring die width was 110 mm, the die hole radius was 1.75 mm, the die hole length L was 35 mm, the percentage of the die opening area was 0.3, the roller radius was 80 mm, and the linear velocity was 6.1 m/s. When the pellet mill was in stability conditions, the torque data were tested in real time, and the average value in one minute was obtained as the torque value. At the same time, the pellets produced in one minute were collected and weighed to compute the volume of production. The tested results were as follows: the torque was 1 518.5 N·m, the production rate was 5.1 t/h, and the constant PN0 was 3.79 kPa. Based on the tested datum, all the model constants were determined and the torque model was developed. In order to verify the torque model, calculations and experiments were carried out in three other different linear velocities. It was shown that the computing datum was very close to the experimental results and the calculation error was less than 3%. The research was helpful to optimizing the structure, reducing energy consumption, and using the pellet mill efficiently.
Number of references:30
Main heading:Pelletizing
Controlled terms:Chemical industry - Computer simulation - Dies - Experiments - Extrusion - Models - Powders - Pressure distribution - Stress concentration - Technology - Torque
Uncontrolled terms:Experimental materials - High-calorific-value - Industrial development - Mathematical analysis - Reducing energy consumption - Ring-die - Stability condition - Structural parameter
Classification code:931.1 Mechanics - 902.1 Engineering Graphics - 901.3 Engineering Research - 901 Engineering Profession - 805 Chemical Engineering, General - 804 Chemical Products Generally - 802.3 Chemical Operations - 723.5 Computer Applications - 603.2 Machine Tool Accessories - 536 Powder Metallurgy - 535.2.2 Metal Forming Practice - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties
DOI:10.3969/j.issn.1002-6819.2013.24.005
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248520
Title:Application of decision tree classification to rubber plantations extraction with remote sensing
Authors:Liu, Xiaona (1); Feng, Zhiming (1); Jiang, Luguang (1)
Author affiliation:(1) Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China; (2) Shandong Jianzhu University School of Management Engineering, Ji'nan 250101, China
Corresponding author:Feng, Z.(fengzm@igsnrr.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:163-172
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The border region of China, Laos and Myanmar (BRCLM) has attracted much international attention due to the special geo-economic and geo-political characteristics, as well as being the hinterland of the world's famous "Golden Triangle, " and the optimal rubber planting areas for Chinese investment. Monitoring the spatial-temporal pattern of the rubber plantations is significant for regional land resource development, eco-environment protection, and maintaining border security. Based on Landsat remote sensing image data and MODIS-NDVI data, rubber plantations were extracted by the decision tree classification method in BRCLM using spectral features and texture characteristics. The results showed that: (1) On account of spectral differences between rubber forests at different growth stages, we were able to extract rubber plantations according to young rubber forest (<10 a) and mature rubber forest (≥10 a) respectively. The optimum temporal window to discriminate rubber plantations was from early January to late March, which is especially appropriate for mature rubber forest. Mature rubber forest, dry land with high vegetation cover, and forest land were prone to misclassification. Meanwhile, young rubber forest, tea plantation, shrubland and grassland were confused with each type in spectral characteristics according to the index of NDVI. (2) Based on the original spectral characteristics, normalized indices, K-T transform indices, and texture features, we established young rubber forest and mature rubber forest decision tree classification models respectively. The overall accuracy of the mature rubber forest went beyond 90%, and the young rubber forest beyond 75%, which meant that the decision tree method was better for mature rubber forest extraction. The rubber plantation distribution maps were obtained using the established decision tree models in 1980, 1990, and 2000 with high classification accuracy, which indicated that the models were simple and efficient for extracting rubber plantations in the tropical areas. This is an effective method for perennial vegetation extraction and classification accuracy verification. (3) From 1980 to 2010, the size of rubber plantations in BRCLM increased nearly nine times, from 705 km2 to 6 014 km2, and the expansion rate of the young rubber forest was faster than that of the mature rubber forest. National differences of rubber plantations in BRCLM were significant, and the cross-border planting developed quickly in the recent 10 years. Rubber plantations in BRCLM will definitely expand across the borders of China to the territories of Laos and Myanmar.
Number of references:26
Main heading:Forestry
Controlled terms:Classification (of information) - Data mining - Decision trees - Extraction - Image reconstruction - Remote sensing - Rubber - Rubber plantations - Vegetation
Uncontrolled terms:Border regions - Classification accuracy - Decision tree classification - Different growth stages - Myanmars - Spectral characteristics - Texture characteristics - Vegetation extractions
Classification code:922 Statistical Methods - 821.0 Woodlands and Forestry - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 818.1 Natural Rubber - 961 Systems Science - 802.3 Chemical Operations - 731.1 Control Systems - 723.3 Database Systems - 716.1 Information Theory and Signal Processing - 741 Light, Optics and Optical Devices
DOI:10.3969/j.issn.1002-6819.2013.24.022
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248533
Title:Impedance characteristics measurements to assess physical indicators in pasteurized milk
Authors:Yang, Na (1); Jin, Yamei (1); Xue, Liping (1); Liu, Piaopiao (1); Xie, Zhengjun (2); Jin, Zhengyu (2); Xu, Xueming (2)
Author affiliation:(1) School of Food Science and Technology, JiangNan University, Wuxi 214122, China; (2) State Key Lab of Food Science and Technology, JiangNan University, Wuxi 214122, China
Corresponding author:Xu, X.(xmxubest@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:275-283
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The knowledge of electrical properties measurements may hold a potential to develop a rapid technique for quality evaluation or determination of concentration and freshness of foods. Especially impedance characteristics measurements in a frequency range focus on unstructured food materials which do not exhibit a structure with insulating cell membranes including milk, edible oil, juice, whole egg products, or homogenized food. Previous researches have not been reported on two plate electrodes method for detecting pasteurized milk adulteration and deterioration. In this research, the impedance characteristics of UHT whole, low fat and skim milk at room temperature were investigated over the frequency range from 20 Hz to 12 MHz. The measurements were conducted with a impedance analyzer was connected to a specially constructed parallel-plate capacitor sample holder at the constant voltage 200 mV. The parallel-plate capacitor with micrometer was designed with height 1 mm by diameter 18 mm. One series of measurements was made on successive dilutions of three kinds of pasteurized milk. Meantime three samples were left at room temperature in parafilm covered beakers for two weeks. The spectrums of these were measured over this period as the milk spoiled. The results showed no obvious correlation between impedance parameters and fat content was observed. The impedance amplitude was greatly affected by the water content. The increasing water content triggered a increase in impedance values of pasteurized milk, irrespective of the measuring voltage frequency. An equivalent electrical circuit of pasteurized milk was deduced for the measured impedance data. By using of ZSimpWin software, the electrical parameters of the equivalent electrical circuit were extracted and the relationships between these electrical parameters and the quality indicators of pasteurized milk were analyzed. Exponential correlations between dilution ratio and equivalent resistance were characterized by R2 values of 0.8337. The impedance amplitude of pasteurized milk decreased monotonically and yet phase angle decreased first and then increased as frequency increased. Each combination of concentration and freshness levels were statistically analyzed at 20 Hz, 121 Hz, 1033 Hz, 11.4 kHz and 12 MHz. Exponential regression relationship between impedance amplitude and dilutions ratio were characterized by R2 values of 0.9887 (whole milk at 20 Hz) and 0.9493 (skim milk at 1033 Hz). However, obvious linear correlations between dilution ratio and phase angle were found in low fat milk with coefficients of determination of 0.9846 at 11.4 kHz. Logarithmic regression relationship between phase angle and storage time were founded in low fat milk, with coefficients of determination of 0.889. The components in milk are decomposed into various acids and other inorganic materials with the growth of microorganisms during storage in room temperature. The freshness was not the most significant factor affecting the impedance characteristics of pasteurized milk. Impedance amplitude, phase angle and equivalent resistance of these electrical parameters can quantify physical indicators of pasteurized milk in the characteristic frequency. This works provide interesting insights aimed at developing a rapid method for determination of physical properties of unstructured food.
Number of references:25
Main heading:Pasteurization
Controlled terms:Capacitors - Cell membranes - Digital storage - Dilution - Electric network analysis - Electric properties - Energy storage - Equivalent circuits - Growth (materials) - Networks (circuits) - Oils and fats - Sensory perception - Storage (materials)
Uncontrolled terms:Characteristic frequencies - Equivalent electrical circuits - Exponential correlation - Exponential regression - Impedance characteristics - Parallel plate capacitors - Pasteurized milk - Regression relationship
Classification code:951 Materials Science - 822.3 Food Products - 822.2 Food Processing Operations - 801 Chemistry - 722.1 Data Storage, Equipment and Techniques - 704.1 Electric Components - 703.1.1 Electric Network Analysis - 703.1 Electric Networks - 702 Electric Batteries and Fuel Cells - 701.1 Electricity: Basic Concepts and Phenomena - 694.4 Storage - 461.4 Ergonomics and Human Factors Engineering - 461.2 Biological Materials and Tissue Engineering
DOI:10.3969/j.issn.1002-6819.2013.24.036
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248531
Title:Dynamic monitoring land-cover change in Hubei province using object-oriented technology and remote sensing imagery
Authors:Luo, Kaisheng (1); Li, Rendong (1); Chang, Bianrong (1); Qiu, Juan (1)
Author affiliation:(1) Institute of Geodesy and Geophysics, Chinese Academy of Sciences, Wuhan 430077, China; (2) Graduate University of Chinese Academy Sciences, Beijing 100049, China; (3) Key Laboratory for Environment and Disaster Monitoring and Evaluation of Hubei Province, Wuhan 430077, China
Corresponding author:Li, R.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:260-267
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The rapid development of RS, GIS, and GPS technology provide a fast and effective means for the dynamic monitoring of land-cover change detection. Many scholars have researched constructing a land-cover change dynamic database with various remote sensing imageries. In conclusion, the main sources to date are abroad remote sensing imagery, while the Chinese HJ-CCD imageries rarely are used in cover-wetlands information extraction. More important, the traditional pixel-based methods which have been universally applied in land-cover/land-use information extraction for many years cannot meet the application need of land-cover/land-use information extraction because it only uses the spectral features of imagery, ignoring other information that the remote sensing imagery carries. The object-oriented technology not only uses spectral features, but also makes full use of texture features?spatial features, spatial relationship, color space, and the band ration of remote sensing imagery. Based on the data of HJ-CCD imagery in 2010, ETM imagery in 2005, and TM imagery in 2000, integrated into RS, GIS, and GPS technology, an object-oriented method was applied to the remote sensing image classification of land-cover/land-use in Hubei province. First, we achieved land-cover/land-use results as the basal map of a database using object-oriented technology in Hubei province in the e-Cognition software. After checking and improving the results, the Similarity Vectors Change Detection Approach was used to compare with the spectral difference the corresponding objects by segmentation from 2000 to 2005, and from 2005 to 2010.We needed to classify the changed area of two change periods, so the Nearest Neighbor Classification Approach belonging to object-oriented technology was applied to extract land-cover/land-use information. This process in the research contained two key steps: choosing samples and optimizing feature space. Optimizing feature space allowed us to get perfect feature extracting object information. All the results in the unchanged area in 2010 were transformed into the sample Nearest Neighbor Classification Approach needed. We used so many samples that the computer could determine the regulation of every class by detailed analysis. Fusing the classification results in the change area and the unchanged area, the land-cover/land-use results all over Hubei province can be completed successfully according to the districts now. We constructed the land-cover change database in Hubei province in the end. The classification accuracy was assessed using error matrixes though wild samples which were obtained from experimental area by GPS. The research showed that, compared with the traditional classification methods, which only consider the spectral characteristics of the targets, an object-oriented international carbon budget certification classification system comprehensively utilizes more detailed information of the remote sensing imagery including spectral characteristics, texture feature, spatial relationship, color space, and band ratio. Thus, it yields a higher accuracy of classification. The object-oriented method extracted the so-called "object, " which consists of some homogeneous pixels in the process of classification, and the objects showed a low degree of fragmentation. Therefore, this method significantly reduced the disturbance of salt-and-pepper noise in the classification results and can keep the similarity in shape with the natural objects. The research showed that this process and method using RS, GIS, GPS, object-oriented technology based on TM, ETM and Chinese HJ-CCD imagery for monitoring land-cover change information is fast, efficient, high automation, and accurate. However, we found that object-oriented technology has some disadvantages where landscape fragmentation is high.
Number of references:27
Main heading:Object oriented programming
Controlled terms:Database systems - Geographic information systems - Image classification - Image reconstruction - Information retrieval - Land use - Monitoring - Optimization - Pixels - Remote sensing - Research - Signal detection - Space optics - Technology - Textures
Uncontrolled terms:Accuracy of classifications - Classification accuracy - HJ-CCD imagery - Land-cover change - Nearest neighbor classification - Object-oriented technology - Remote sensing image classification - Spectral characteristics
Classification code:901.3 Engineering Research - 921.5 Optimization Techniques - 933 Solid State Physics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 901 Engineering Profession - 403 Urban and Regional Planning and Development - 716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 741 Light, Optics and Optical Devices - 741.1 Light/Optics
DOI:10.3969/j.issn.1002-6819.2013.24.034
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248518
Title:Experiment and development of monitoring system for Bactrocera Dorsalis (Hendel) based on wireless sensors network
Authors:Wen, Tao (1); Hong, Tiansheng (2); Li, Lijun (1); Li, Zhen (2); Ye, Zhijie (2); Zhang, Yanhui (4)
Author affiliation:(1) School of Mechanical and Electrical Engineering, Center South University of Forestry and Technology, Changsha 410004, China; (2) Key Laboratory of Key Technology for South Agricultural Machinery and Equipment, Ministry of Education, Engineering College of South China Agricultural University, Guangzhou 510642, China; (3) Division of Citrus Machinery, China Agriculture Research System, Guangzhou 510642, China; (4) School of Engineering, Hong Kong University of Science and Technology, Hong Kong, Hong Kong
Corresponding author:Hong, T.(tshong@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:147-154
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Bactrocera Dorsalis (Hendel) were invasive pests that were occurred frequently and were seriously harmful for fruit trees' growth and have been ranked an important quarantine object in many countries and regions. So far, the main prevention method for Bactrocera Dorsalis (Hendel) has been chemical pest control, which not only caused serious damages on the economic field but also brought on water and soil resources pollution, ecological system damages, damage to food security and its impact on human health, and a series of major problems. In order to detect the real-time number of Bactrocera Dorsalis (Hendel) and monitor the corresponding environmental information accurately in a large-scale orchard, a wireless sensor network was employed. The dynamic monitoring system included ten pest-sensor nodes, one environmental-sensor node, and one WSN GPRS node, all of which were deployed in the national citrus industry experimental orchards at South China Agricultural University. TinyOS and ZigBee were applied as the operating system and the communication protocol respectively for all monitoring nodes. Mean current consumption for all monitor nodes ranged from 39.52 to 42.72 mA in standby mode and from 92.21 to 95.32 mA under full operating mode. Mean current consumption of the router was kept steadily around 190mA in standby mode, and rose to stay around 250mA under communications condition. The results showed that the solar powering module sufficiently met the system power requirements. The results of the five-month communication experiments indicated that the PLR of all monitor nodes obtained a stable range from 11.9% to 20.8%, which can meet the requirements for long-time monitoring, and the statistics of the PDR had a parabola curve distribution. It meant that the stability of communication was more correlated to crop canopies and atmospheric conditions according to the short-range radio signal propagation theory. It was highly recommended that the antennas be mounted to obtain a line-of-sight communication, if possible, to avoid signal attenuation and distortion introduced by crop canopies. In conclusion, the system achieved stable data transmission suitable for effective Bactrocera Dorsalis (Hendel) monitoring in a large-scale orchard.
Number of references:30
Main heading:Sensor nodes
Controlled terms:Cellular radio systems - Crops - Experiments - Food supply - Monitoring - Orchards - Sensors - Water pollution - Wireless networks - Zigbee
Uncontrolled terms:Atmospheric conditions - Bactrocera Dorsalis (Hendel) - Dynamic monitoring system - Ecological systems - Environmental information - Line of sight communications - Plant protection - Wireless sensors networks
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 901.3 Engineering Research - 821.4 Agricultural Products - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 821.3 Agricultural Methods - 722.3 Data Communication, Equipment and Techniques - 716.3 Radio Systems and Equipment - 453 Water Pollution - 404.2 Civil Defense - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2013.24.020
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248504
Title:Development of 2-axes rotary device for plant wet culture
Authors:Chen, Min (1); Yang, Youquan (1); Deng, Sufang (1); Lin, Yingzhi (2); Zhang, Xiang (3)
Author affiliation:(1) Agricultural Ecology Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350013, China; (2) Digital Agricultural Institute, Fujian Academy of Agricultural Sciences, Fuzhou 350003, China; (3) Mechatronic Engineering College, Fujian Agriculture and Forestry University, Fuzhou 350007, China
Corresponding author:Chen, M.(chenmin863@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:40-48
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to study and operate plant stimulant space growth test on the ground, a 2-axes rotary device for plant moist culture was developed to simulate a space microgravity effect. The overall design, structural features, and operating principle were introduced in this paper. Plant 3-dimensional rotary culture plate rotated on both two orthogonal rotation axes. Revolving speed can be independently and steplessly regulated on line. By the screening and optimizing of medium material in the plant wet culture plate, combining the structural design of critical components such as the water seepage line and a rotating water connector, the medium was always kept wet, but there was no visual water on the face, which was also easy to fix plant root, and provided a good ecological microenvironment for plant growth. The machine outside profile size is 980 mm×1 450 mm ×880 mm, Active area of plant cultivation is 0.12 m2. Revolving speed can be adjusted steplessly on line between 0.5-5 rpm, control accuracy up to ± 3%. In the device, a controlled airtight cabin of 0.38 m3 volume with strict air tightness was built, and a configured plant growth monitoring and integrated environment monitoring system. The system has the abilities of anticorrosive, anti-seepage, anti-rust and preventing volatile gas. All operations and online maintenance should be performed on the front panel. Water pressure test figures out the main technique parameters of the infiltration pipe circuits and the intermitting circulating period of the closed plant nutrition solution transportation system. Performance experiments show that the intermittent cycle supply method of nutrient solution adopted by the device can satisfy the ecological condition of plants moist cultivation. Gas abundance method test showed that airtight cabin has good air tightness. Application experimental analysis showed that wet culture can satisfy the requirements of plant suspension and low velocity 3-dimensional rotary culture. Various performance indicators of the device were needed to meet the design requirements. The 2-axes rotary device for plant moist culture used the plant damp cultivation method and o-type nutrient solution supply technology by rotating wall perfusion to solve the port problem that cyclic broth, power line, and control line transferred between fixed and rotating pipe fittings, which makes it possible to culture a plant for the whole stages under simulated microgravity conditions. This device can be used as ground test equipment and technical support platform for space horticulture, space pharmaceutical and space breeding research, be expected to open a new avenue for botany.
Number of references:30
Main heading:Plants (botany)
Controlled terms:Cultivation - Design - Ecology - Equipment - Equipment testing - Microgravity - Microgravity processing - Nutrients - Plates (structural components) - Structural design
Uncontrolled terms:Ecological conditions - Integrated environment - Performance experiment - Performance indicators - Plant - Simulated microgravity - Simulated microgravity conditions - Transportation system
Classification code:944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 901 Engineering Profession - 821.3 Agricultural Methods - 656.2 Space Research - 656 Space Flight - 461.9 Biology - 454.3 Ecology and Ecosystems - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.24.006
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248512
Title:Calculation of rain collection amount and tank volume in multi-span greenhouse in humid region
Authors:Chen, Xijing (1); Xi, Hui (1); Xiao, Hua (1); Xu, Yuxin (1); Zhang, Ruliang (2); Shen, Alin (1)
Author affiliation:(1) Institute of Environment, Resources, Zhejiang Academy of Agricultural Sciences, Hangzhou 310021, China; (2) Soil and Water Conservation Experiment Station of Lanxi, Lanxi 321100, China
Corresponding author:Shen, A.(shenalin_123@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:103-109
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:As rainfall is large in humid region of southern China, greenhouse rainwater harvesting should be designed to collect rainwater economically and moderately. The capacity of the rainwater tank needs to be determined according to rainwater harvesting plan and demand for irrigation. In order to determine a proper volume of rainwater harvesting tank and search for correlative calculation method, a concept describing the level of rainwater collection, named Rain Collection Volume Modulus is proposed in this paper. Rain Collection Volume Modulus is defined as the rain-collecting facility volume in per 1000 m2 of the rain-collecting area, the unit is mm. We collected meteorological observation data from 1993 to 2012 in the experimental district of Lanxi city Zhejiang Province, and then used exponential decay function to establish fitting equation with Rain Collection Volume Modulus as the independent variables. According to the equation, we can establish a query table containing capacity of rainfall collection, rate of rainwater collection, volume of tank and re-storage times under different Rain Collection Volume Modulus from 5-100 mm (spacing 5 mm) under the condition of 1000 m2 rain-collecting area. In order to calculate the volume of tank in actual practice, we can know the amount of rainwater that can be collected under 1000 m2 rain-colleting area according to the actual rain-collecting area and required rainfall. Therefore, the corresponding Volume Modulus could be found in the table. And the volume of tank could be calculated by multiplying the mentioned Rain Collection Volume Modulus and actual rain-collecting area. The same Rain Collection Volume Modulus means the same rain-collecting rate and same re-storage times. Meanwhile, different Rain Collection Volume Modulus could satisfy different economical demand of rainwater harvesting project. The error analysis shows that there is no obvious relationship between the calculation error with rainfall, and there is no significant discrepancy between Rain Collection Volume Modulu and the relative error, but the former is in proportion to absolute error. The study shows that the accuracy of calculated value is influenced by rainfall intensity, therefore, unusual rainfall that deviates from the average over the years will cause large error. Rainfall is too concentrated in 4 years among 20 years, causing a great loss of rainwater, so the error is higher. The result shows that the relative errors are basically within 10%. Nearly half of the errors were less than 5%, and the maximum absolute value of them was 26.2%. The absolute value of 20-year average relative error was 6.6%, which almost matched the difference of rainfall. Our study was completed in the average rainfall of 1500 mm, which showed that the accuracy of calculation had no significant relationship with rainfall, so the calculation method can be applied to this locality, and also it is an important reference to most parts of the South China where the rainfall is between 1 000 mm to 2 000 mm.
Number of references:20
Main heading:Rain
Controlled terms:Calculations - Digital storage - Errors - Greenhouses - Tanks (containers)
Uncontrolled terms:Average relative error - Exponential decay functions - Independent variables - Meteorological observation - Rain water harvesting - Rainwater collections - Re-storage times - Volume of tank
Classification code:731 Automatic Control Principles and Applications - 723 Computer Software, Data Handling and Applications - 722.1 Data Storage, Equipment and Techniques - 921 Mathematics - 721 Computer Circuits and Logic Elements - 443.3 Precipitation - 402.1 Industrial and Agricultural Buildings - 619.2 Tanks
DOI:10.3969/j.issn.1002-6819.2013.24.014
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248511
Title:Hydrodynamic process of soil erosion in steep slope of engineering accumulation
Authors:Zhang, Letao (1); Gao, Zhaoliang (1); Tian, Hongwei (4)
Author affiliation:(1) Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling 712100, China; (2) University of Chinese Academy of Sciences, Beijing 100049, China; (3) Institute of Soil and Water Conservation, Northwest Agriculture and Forestry University, Yangling, 712100, China; (4) College of Resource Environmental Sciences, Northwest Agriculture and Forestry University, Yangling 712100, China
Corresponding author:Gao, Z.(gzl@ms.iswc.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:94-102
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Soil erosion newly derived from engineering accumulation severely threatens ecological safety of construction sites and surrounding areas. It is of great necessity to carry out researches on hydrodynamic process of soil erosion originated from engineering soil deposits, and develop prediction model of soil erosion in production and construction areas. A set of field pouring water scouring experiments were conducted on the experimental plot with 72.7% gradient and 12-meter length, which lies in a steep slope of a typical spoil ground along the line of Shenfu freeway, to investigate the hydrodynamic process of soil erosion of the engineering accumulation. At the upper slope of runoff plot, a watering system consisting of submersible pump, water segregator, valves, flowmeter, overflow tank and impermeable fabric was set up achieve desired discharges. Inflow discharges were designed according to calculated unit discharge occurred on experimental plot under a certain rainstorm frequency and determined by pre-experiment. During the whole experimental process, 4 evenly spaced observation sections were down slope arranged to conduct soil sampling, flow velocity measurement and water-crossing section observations. At the bottom of experimental plot, a bucket was designed to collect all the runoff and sediment, and take samples during different intervals at different stages of experimental process. The process of runoff producing and sediment yielding can be deduced and calculated from the water level recording in the bucket and samples. A single trial persisted 40-50 minutes. Preliminary result reveals that: 1) relationships between flow shear stress, stream power, flow kinetic energy and soil detachment rate under sheet flow erosion all can be expressed by linear equation, except that effects of unit stream power and unit energy of water-carrying section on sheet flow erosion rates are not significant; 2) soil detachment rate under rill erosion conditions can be described with log-linear equation of runoff kinetic energy, and also linearly relates to flow shear stress, stream power, and unit energy of water-carrying section respectively; 3) stream power is the best hydrodynamic parameter simulating changing trend of soil detachment, and should be the power source of slope erosion; 4) critical unit stream power for rill erosion is 3 N · m-1 · s-1, the value of rill erodibility parameter is 8×10-3 s2 · m-2. In terms of fitting effect, the parameters tested should be ranked in the order of stream power > runoff kinetic energy > flow shear stress > unit energy of water-carrying section > unit stream power for sheet flow erosion, and stream power > unit energy of water-carrying section > unit stream power > flow shear stress > runoff kinetic energy for rill erosion, which indicates that mechanics parameters and energy parameters have different advantages on descriptions of dynamic process of soil erosion in steep slope of engineering soil deposit, which should be determined on practical considerations instead of lumped together. The result obtained may lay the foundation for the establishment of process-based model of soil erosion initiated by engineering accumulation, and provide scientific guidance for comprehensive control of newly arising soil & water loss in production and construction areas.
Number of references:34
Main heading:Soil conservation
Controlled terms:Deposits - Engineering - Erosion - Experiments - Hydrodynamics - Kinetic energy - Kinetics - Linear equations - Piles - Rivers - Runoff - Shear stress - Soils - Storms - Water levels
Uncontrolled terms:Comprehensive controls - Hydrodynamic parameters - Hydrodynamic process - Process-based modeling - Runoff and sediments - Scouring experiments - Steep slope - Stream power
Classification code:617 Turbines and Steam Turbines - 631.2 Hydrodynamics - 901 Engineering Profession - 612 Engines - 901.3 Engineering Research - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics - 921 Mathematics - 532 Metallurgical Furnaces - 407.2 Waterways - 408.2 Structural Members and Shapes - 421 Strength of Building Materials; Mechanical Properties - 407 Maritime and Port Structures; Rivers and Other Waterways - 443.3 Precipitation - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 444.1 Surface Water
DOI:10.3969/j.issn.1002-6819.2013.24.013
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248522
Title:Feature description for nutrient deficiency rape leaves based on multifractal theory
Authors:Wang, Fang (1); Liao, Guiping (2); Wang, Xiaoqiao (2); Li, Jianhui (2); Li, Jinwei (2); Shi, Wen (1)
Author affiliation:(1) Science College, Hunan Agricultural University, Changsha 410128, China; (2) Agricultural Information Institute, Hunan Agricultural University, Changsha 410128, China
Corresponding author:Liao, G.(lgpxf@hunau.net)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:181-189
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Fertilization levels play a critical role in crops' growth. As a vital organ of rapeseed, leaves can well reflect the nutritional level, and their images are always processed and analyzed by a computer vision system. The texture feature of the leaves' images is very important to become a key indicator to describe the nutritional status for the rapeseeds. In recent years, multifractal methods were used to extract its features for describing a texture image. The traditional type of multifractal analysis (MFA) was calculated based on the standard partition function multifractal formalism, which describes stationary measurements. For a crop image collected in field crops, the surface itself is hardly stationary and whose gray scale volatility is likely to be more bizarre. By this token, this is not always a valid choice to analysis them based on MFA. A novel method: local multifractal detrended fluctuation (LMF-DFA) analysis was proposed in this paper to extract texture feature of every pixel for a self-similar surface based on the method of 2-D multifractal detrended fluctuation analysis (MF-DFA), which can well portray multifractal features for a non-stationary surface. A set of new multifractal descriptors, namely the local multifractal fluctuation exponents Lh<inf>ij</inf> (q) were defined to portray every pixels' feature effectively, the LMF-DFA exponents were calculated by a slipping window of sizes w×w. In our study, we took w=11.The components of the LMF-DFA spectrum which are used to distinguish between different textures can be considered statistically significant. As an important application, we applied the method to disclose a rapeseed leaf's image of nutrient deficiency. Four kinds of nutrient deficiency of rapeseed leaf's images, namely, Nitrogen deficiency, Phosphorus deficiency, Potassium deficiency, and Magnesium deficiency, were chosen for our two experiments. In order to extract real and accurate information by the proposed method, in every image the background was are removed, and circumscribed by a minimum bounding rectangle, which is the so-called standardization process. In our first experiment, initially, for each image, we calculated a set of Lh<inf>ij</inf> (q) for the value of q=-10 to 10. And then we used Lh<inf>q</inf> which is an average of the Lh<inf>ij</inf> (q) over all pixels, to represent the multifractal feature for each image. The result illustrated that the calculated Lh<inf>q</inf> exponents can differentiate them well. Meanwhile, it points out that the discriminant effect of Lh<inf>q</inf> exponents are best when the value q = {-10,-9,-8, -7,-6} by an analysis of variance. In our second experiment, fuzzy C-means clustering was used to process fuzzy segmentation for the Magnesium deficiency of a rapeseed leaf's image, which contains some representative regions of nutrient deficiency. Both the proposed Lh<inf>ij</inf> (q) exponents and other two characteristics which are the traditional gray value and the classic H?lder exponent calculated by standard multifractal analysis were applied to the segmentation experiment. The comparison results demonstrated that the LMF-DFA estimation can provide most robust segmentations. The meaningful work provides a theoretical and practical method for the identification and diagnosis of a crop leaf's nutrient deficiency. Moreover, it provides a precise positioning method for key areas of crop leaves' nutrient deficiency.
Number of references:32
Main heading:Image texture
Controlled terms:Computer vision - Crops - Experiments - Feature extraction - Fractals - Fuzzy systems - Image processing - Image segmentation - Magnesium - Nutrients - Oilseeds - Pixels - Plants (botany) - Textures - Two dimensional
Uncontrolled terms:Brassica Napus L - Computer vision system - Fuzzy C means clustering - Minimum bounding rectangle - Multifractal detrended fluctuation analysis - Multifractal fluctuations - Multifractal formalism - Standardization process
Classification code:933 Solid State Physics - 921 Mathematics - 901.3 Engineering Research - 821.4 Agricultural Products - 961 Systems Science - 723.5 Computer Applications - 716 Telecommunication; Radar, Radio and Television - 542.2 Magnesium and Alloys - 461.9 Biology - 723.2 Data Processing and Image Processing
DOI:10.3969/j.issn.1002-6819.2013.24.024
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248529
Title:Effect of porogen on nutrient release from vegetable oil coated urea
Authors:Liu, Hailin (1); Fan, Xiaolin (1)
Author affiliation:(1) Environment Friendly Fertilizer Engineering Technology Research Center of Guangdong College, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Fan, X.(xlfan@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:244-250
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Adding porogen is often used as one of the key technologies regulating nutrient release from fertilizers. Adding porogen can artificially changes the coating porosity, pore diameter size, structure close degree, then adjusting the permeability of coating and controlling the nutrient release rate., In this paper, we studied the effect of porogens on nutrient release of vegetable oil coated urea and potentials for applying this technology for the development of controlled release fertilizer. The vegetable oil coated urea was prepared using the best surface reaction coating technology of manufacturing controlled release fertilizer in China. The mixed vegetable oil consisted of tung oil, castor oil, peanut oil, soybean oil, cottonseed oil, the coating materials were then mixed with vegetable oil and curing agent through. lateral or base jet vortex fluidized bed., resulting six percent of urea. ST and SB were used as porogens in this experiment, ST is water soluble starch, SB is easy to swell in water. The experiments were performed under the still pure water dissolving incubation. We set up three temperature gradients with 25°C, 30°C and 35°C, respectively. The refractive index method was used for analyzing the urea content in the coated urea incubation solution, the nutrient release rate and longevity of vegetable oil coated urea were computed. The effects of adding porogen on nutrient release curves, temperature dependence and nutrient release activation energy of vegetable oil coated urea were analyzed, the relationship between nutrient release from vegetable oil coated urea and the amount of porogens was developed. The results showed that adding either ST or SB accelerated the nutrient release from vegetable oil coated urea, and shorted the longevity. If the amount of ST was added as 1%, 3%, 5%, the longevity of vegetable oil coated urea was shorten to 29.78, 60.78, 67.44 days, respectively. The longevity of vegetable oil coated urea was reduced with the increased proportion of ST. The nutrient release curves of coated urea with different proportion of SB was almost identical. The temperature dependence Q10 was reduced with increased ST. However, the temperature dependence Q10 was increased with increase of SB. In addition, nutrient release activation energy of vegetable oil coated urea was decreased by adding porogen.
Number of references:31
Main heading:Nutrients
Controlled terms:Activation energy - Coated materials - Coatings - Experiments - Fertilizers - Fluidized beds - Metabolism - Refractive index - Surface reactions - Temperature distribution - Urea - Vegetable oils
Uncontrolled terms:Coating porosity - Coating technologies - Controlled-release fertilizers - Different proportions - Nutrient release - Porogens - Temperature dependence - Water soluble starch
Classification code:821.2 Agricultural Chemicals - 813 Coatings and Finishes - 804.1 Organic Compounds - 804 Chemical Products Generally - 802.2 Chemical Reactions - 901.3 Engineering Research - 802.1 Chemical Plants and Equipment - 741.1 Light/Optics - 641.1 Thermodynamics - 539 Metals Corrosion and Protection; Metal Plating - 461.9 Biology - 801.4 Physical Chemistry
DOI:10.3969/j.issn.1002-6819.2013.24.032
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248519
Title:Investigate maize ear traits using machine vision with panoramic photography
Authors:Wang, Chuanyu (1); Guo, Xinyu (1); Wu, Sheng (1); Xiao, Boxiang (1); Du, Jianjun (1)
Author affiliation:(1) Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China; (2) National Engineering Research Center for Information Technology in Agriculture, Beijing 100097, China; (3) Key Laboratory for Information Technology in Agriculture, Ministry of Agriculture, Beijing 100097, China
Corresponding author:Guo, X.(guoxy@nercita.org.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:155-162
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Maize ear morphological characteristics have important applications in breeding, germplasm, and cultivation areas, subject to the extent of technology development in relevant areas, but the approach of surveying morphological characteristics is not highly automatic. In this paper, we present a new machine vision based method and a supporting device for maize ear morphological characteristic surveying. First, the maize ear was placed on a rotating component, which rotates the maize ear in a fixed angle interval in order to capture 16 images more or less. A preprocess was carried out of maize ear image sequences to remove the image background, and the remaining part of the maize ear image was passed to the next process. The SIFT (Scale Invariant Feature Transform) was used to extract image feature points, and the feature points in the neighboring images could be matched up according to SIFT feature points. The relative motion between the two images could be described by a homography, and an overdetermined equations composed of matching points and homography make specific values of homography available. Mismatched feature points will reduce the accuracy of the homography equation solution dramatically. We adopted a RANSAC (random sample consensus) method to remove the outlier of the matching points during the homography solving process. Secondly, according to the motion described by homography, the first image and the next image are registered to the same coordinate system, using the dynamic programming method to find the seam-line in the two images, cutting the redundancy region in the two images along the seam-line. Since the exposure of the two images had certain differences which led to image brightness near seam-line being slightly different, a weighted Gaussian filter was imposed on both sides of the stitching image to eliminate exposure difference. Finally, the fusion image according to the order in sequence generated the ear panorama, row number, number in a row, kernel number, and other parameters were extracted by processing the maize ear panorama. The experimental results showed that: there is no significant difference between the method proposed by this paper and manual measurement, and the method proposed can greatly strengthen the automation of the maize ear traits investigation.
Number of references:26
Main heading:Computer vision
Controlled terms:Image fusion - Image registration - Surveys
Uncontrolled terms:Dynamic programming methods - Maize ears - Morphological characteristic - Panoramas - Panoramic photographies - Random sample consensus - Scale invariant feature transforms - Technology development
Classification code:405.3 Surveying - 723.2 Data Processing and Image Processing - 723.5 Computer Applications
DOI:10.3969/j.issn.1002-6819.2013.24.021
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248499
Title:Technology innovation development strategy on agricultural aviation industry for plant protection in China
Authors:Zhou, Zhiyan (1); Zang, Ying (1); Luo, Xiwen (1); Lan, Yubin (3); Xue, Xinyu (4)
Author affiliation:(1) Key Laboratory of Key Technology for South Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (2) College of Engineering, South China Agricultural University, Guangzhou 510642, China; (3) United States Department of Agriculture, Agricultural Research Service, Aerial Application Technology Research Unit (USDA-ARS-AATRU), TX 77845, United States; (4) Key Laboratory of Crop Protection Machinery, Nanjing Agricultural Mechanization Institute, Ministry of Agriculture, Nanjing 210014, China
Corresponding author:Luo, X.(xwluo@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:1-10
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Based on the review of the current status and perspectives of worldwide agricultural aviation (AA) and completive analysis of the technology demand, the development strategies of aviation plant protection in China were recommended. The main restricting factors to the development of AA industry in China were pointed out, which including the imperfect policies and regulations of AA at present, lack of supporting core technologies, qualified AA professionals, understanding on AA, public support to the development of AA, and defective social service system in AA, etc. And then the countermeasures to promote the rapid and healthy development of AA in China were put forward, which including the adoption of multi-type and multi-operation models to improve the applicability of AA, increasing the capital investment to enhance the core technologies research, fortifying targeted policies to strengthen and standardize the management of AA. Finally, the demand prediction of agricultural aircraft type in China was conducted by using empiric estimation demand prediction method. The demand prediction analysis shows that the AA industry in China has not really started, and the market will dramatically increase. In the coming 15 years, the AA aircraft type in China will mainly include manned fixed-wing aircraft, manned helicopter, gasoline-powered unmanned aerial vehicle (UAV), battery-power UAV and others, and the working area to the whole cultivated area of all of these aircraft type will be about 5% by the end of 2015, 20% by 2020, 40% by 2025, 50% by 2030 respectively. It was estimated about 46.5 billion RMB of the new investment on AA aircraft type in next 15 years. With the relevant system and supporting core technologies improving continuously, the AA industry will get a healthy, orderly and rapid development in China.
Number of references:34
Main heading:Fixed wings
Controlled terms:Agriculture - Aircraft - Aviation - Forecasting - Investments - Strategic planning - Technology - Unmanned aerial vehicles (UAV)
Uncontrolled terms:Agricultural aircraft - Aviation plant - Demand forecasting - Development strategies - Fixed-wing aircraft - Forcasting - Restricting factors - Technology innovation
Classification code:431.1 Air Transportation, General - 652.1 Aircraft, General - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901 Engineering Profession - 911.2 Industrial Economics - 912.2 Management
DOI:10.3969/j.issn.1002-6819.2013.24.001
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248524
Title:Determination and grading of Anthurium based on machine vision
Authors:Li, Kai (1); Yang, Yanli (1); Liu, Kai (1); Gu, Song (1); Zhang, Qiang (1); Zhao, Liang (3)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou 510642, China; (2) Key Laboratory of Key Technology on Agricultural Machine and Equipment, South China Agricultural University, Ministry of Education, Guangzhou 51064, China; (3) Tianjin Binhai International Flower Science and Technology Park Co., Ltd, Tianjin 300300, China
Corresponding author:Gu, S.(sgu666@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:196-203
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:With the raising of our consumption, the sales of flowers keep on expanding. Anthurium, as a prominent example, is facing some problems. Productivity and identical grading standards are restricted by the traditional method of grading in the actual process of production. These issues affect the quantity and quality of the product in China. In this paper, an online determination and grading method based on machine vision was developed. The variety of test materials was "flame, " which is popular in China. In accordance with the national standard, 30 pots of red anthurium of grade A, 30 pots of grade B and 30 pots of grade C, a total of 90 pots, were chosen to be test materials. After integrating national standards, the Ministry of Agriculture standards, and local standards about flowering potted plant, new standards were drawn out which are suitable for machine vision grading. In the standards, height, crown diameter, spathe quantity, and spathe diameter were to be the four items to be determined for every potted red anthurium. A horizontal camera and a vertical camera were used in this method to capture the side view and top view photos of 90 Anthurium one by one at the same time. After binarization and edge-based segmentation, the side contour, top contour, and spathe contour were extracted out. The side view photo was scanned in, the first point of side contour was obtained, and this point was regarded as the top point of this plant. The height could be calculated out through the coordinate of the top point. The result obtained by the traditional method, measured with a tapeline, was taken as the normal height. Experimental results show that the measurement error of height was less than 5.4 mm by the machine vision method. To reflect the growth state of the plant more accurately, this paper put forward an equivalent diameter method to use instead of crown diameter. In the top view photo, the crown area of each red anthurium was drawn out from the top contour, the top contour was transformed to an equivalent circle with the same area; and the diameter of equivalent circle was the equivalent diameter of the crown. There always may be some empty holes or gaps between leaves for a big-leaf plant in the top view photo. Therefore, the equivalent diameter method can avoid the effect of the empty holes and gap on the growth state of the plant. This method is more precise than using crown diameter. To count out the number of spathe in one red anthurium, an identification model of spathe was trained, which is complete and symmetry, and arranged all the identified spathe by similarity rate with the identification model from spathe contour. The result of this experiment showed that the correct rate for counting was up to 100% for the 90 pots red anthurium. Taking certain spathe with the highest similarity rate as the target, the widest diameter that is perpendicular with the main nervure was measured. Taking the result by traditional method, measurement was obtained with a tapeline as the normal spathe diameter. The maximum relative error of the spathe diameter was 6.5%. The result of the validate experiment showed that the success rate was up to 97.8% for grading 90 pots of red anthurium. This means that the method based on machine vision fulfilled the objective, which is online determination and grading for potted red anthurium.
Number of references:27
Main heading:Grading
Controlled terms:Cameras - Computer vision - Experiments - Image segmentation - Plants (botany) - Standards
Uncontrolled terms:Equivalent diameter - Flowering potted plants - Grading standards - Identification model - Maximum relative errors - National standard - On-line determination - Red anthurium
Classification code:913.3 Quality Assurance and Control - 902.2 Codes and Standards - 901.3 Engineering Research - 742.2 Photographic Equipment - 741.1 Light/Optics - 723.5 Computer Applications - 461.9 Biology
DOI:10.3969/j.issn.1002-6819.2013.24.026
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248510
Title:Evaluation of border irrigation performance based on principal component analyses
Authors:Li, Shiyao (1); Cai, Huanjie (1); Chen, Xinming (1)
Author affiliation:(1) Key Lab. of Agricultural Soil and Water Engineering of Northwest Agriculture and Forest University, Yanglin 712100, China; (2) Chinese Arid Area Research Institute of Water-saving Agriculture, Northwest Agriculture and Forestry University, Yangling 712100, China
Corresponding author:Cai, H.(caihj@nwsuaf.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:86-93
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The numerous influential factors and evaluation indexes of border irrigation performance usually result in big difficulties in the analysis and evaluation of such irrigation. Establishing a concise, representative and credible evaluation indicator of irrigation performance is a basic and key problem. Based on field experimental data, the Elliott and Walker's Two-Point Method of WinSRFR4.1 model was used to simulate the process of irrigation according to the field irrigation experiment in the Guanzhong Plain in Shaanxi Province, the method uses the two observed advance times to set up two mass balance equations, which verified the model and parameter selected. On this basis, the weighted sum of different evaluation indices was used as a comprehensive index for the evaluation of border irrigation performance through principle component analysis. Then, this index was used to evaluate and analyze the performance of border irrigation in the Guanzhong Plain in Shaanxi Province. Results showed that WinSRFR4.1 model effectively simulated the hydraulic processes, that is, the advance of the surface water flow, although there were some points that deviated from the fitting curve due to the change in hydraulic conditions after the water supply stopped. The error resulting from simulated advance time and observed advance time was less than 1.0 min among the twenty-five irrigation events. This indicates that WinSRFR4.1 model is able to evaluate border irrigation performance. The comprehensive principle component index of border irrigation performance followed a normal distribution and could represent 96.74% of variation in irrigation performance. It is proved to be a representative and objective index and could be used as an index for the evaluation of overall performance of border irrigation. Analyses with this index showed that both border length and inflow cutoff have significant effects on border irrigation performance. The order of influential factors based on their decreasing influences on border irrigation performance is as: inflow cutoff, border length, slope, flux per width, irrigation quota, infiltration coefficient, roughness coefficient, and infiltration index. With comprehensive consideration of the relationship among irrigation quality, irrigation quota and the border length, ncreasing irrigation quota can improve the irrigation performance while large irrigation quota may also lead to bad irrigation performance as the increase of border length. There were mutual antagonistic or synergistic effects among the influential factors above. The method proposed in this paper can much better reflect the actual irrigation performance of border irrigation and provide a proper irrigation scheme with theoretical foundation and technological support.
Number of references:20
Main heading:Infiltration
Controlled terms:Computer simulation - Curve fitting - Irrigation - Normal distribution - Principal component analysis - Water supply
Uncontrolled terms:Analysis and evaluation - Correlation analysis - Evaluation - Flow - Infiltration coefficients - Irrigation performance - Principle component analysis - Theoretical foundations
Classification code:446.1 Water Supply Systems - 452.1 Sewage - 723.5 Computer Applications - 821.3 Agricultural Methods - 922.1 Probability Theory - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2013.24.012
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248525
Title:Engineering design of solar and power waste energy heating system for biogas project
Authors:Kou, Wei (1); Zheng, Lei (2); Qu, Jingxia (2); Shao, Lijie (2); Zhang, Dalei (2); Pei, Zhanjiang (1); Liu, Qingyu (1)
Author affiliation:(1) Shenyang Agricultural University Engineering college, Shenyang, 110136, China; (2) Liaoning Institute of Energy Resource, Yingkou 115003, China
Corresponding author:Liu, Q.(qyliu@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:211-217
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Biogas projects have been rapidly developed in China due to their energy efficiency and environmental benefit. However, the microorganism in fermentor is inactivate and biogas production will be dramatically declined if the temperature in biogas fermentor is unstable or is too low. Sofar many biogas projects only operate stably in Southern China. It is difficult to expend the larger and medium-sized biogas projects in Northern China. Because the thermal insulation in this region cannot support the biogas fermentation. In this study, a set of heating system that composed of solar and power waste energy were tested. This technology was demonstrated for a middle temperature fermentation project in Harbin Shuangcheng city. The design principle is discussed in this paper. Some key parameters including fermentation heat load, generator heat recovery utilization rate, and thermal efficiency of solar collector unit were calculated theoretically to verify whether this heating system can meet the middle temperature condition. The results showed that averaged daily heat loss for this biogas project was 6659.2 MJ during the whole year. Solar energy-power waste heating system used in intermediate temperature anaerobic fermentation can store averaged 7017.6 MJ heat per day. Because of larger temperature difference during the year in Northern China, adding heat and losing heat of the biogas project were analyzed for each month through the comparison analysis of heat supplement and loss. The biogas project needs additional 372.2, 369.4 and 208.3 kWh power from the biogas generator in December, January and February to ensure the project stable operation. In remaining months, the heating system was able to meet the middle temperature for the project. Further testing for the temperature raising effects by this heating system was conducted in August. Results showed that the fermentation raw material in primary fermentor can achieve 35°C after 28 days' heating,, and satisfy the middle temperature condition. With high quality solar energy resources in Northern plains, combining the solar energy and biogas power generation waste energyis bale to reduce the generator heat waste and regulate the heating system by controlling the biogas generator. The combined heating system in this biogas project can reduce the investment system. It is expected that this paper will assist designing a heating system to for the stable operation of biogas projects in Northern China.
Number of references:33
Main heading:Biogas
Controlled terms:Design - Energy efficiency - Energy resources - Fermentation - Fermenters - Heating - Heating equipment - Investments - Low temperature production - Quality control - Solar energy - Waste heat
Uncontrolled terms:Anaerobic fermentation - Biogas fermentation - Environmental benefits - Heating system - Intermediate temperatures - Middle temperatures - Power waste - Temperature differences
Classification code:913.3 Quality Assurance and Control - 911.2 Industrial Economics - 802.2 Chemical Reactions - 802.1 Chemical Plants and Equipment - 644.4 Cryogenics - 643.1 Space Heating - 642.2 Industrial Furnaces and Components - 615.2 Solar Power - 525 Energy Management and Conversion - 522 Gas Fuels - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.24.028
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517250486
Title:Adding black particles in brackish water reduces water transmission properties of solar desalination system
Authors:Chang, Zehui (1); Zheng, Hongfei (1); Hou, Jing (3); Jia, Yan (2); He, Fengbo (1)
Author affiliation:(1) School of Mechanical and Vehicular Engineering, Beijing Institute of Technology, Beijing 100081, China; (2) College of Energy and Power Engineering, Inner Mongolia University of Technology, Hohhot 010051, China; (3) College of mechanical electrical heating and ventilation engine, Inner Mongolia Technical College of Construction, Hohhot 010070, China
Corresponding author:Chang, Z.(changzehui@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:204-210
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The lack of drinking water has been a great challenge for humanity and will continue in the future. Previous research indicated that brackish water can be treated using solar energy with no negative impact on the environment. However, the biggest main obstacles for solar brackish water desalination technology are high cost and applied at small scale. Because the low efficiency of the solar collector system at high temperature (≥ 100°C) and low efficiency of the brackish water desalination system at low temperature are not consistent. In this study, a strong concentrating light and direct heating type solar brackish water system was testedd through utilizing the high efficient concentrating solar energy system. This kind of system produced high strength solar energy and could concentrate them to the brackish water directly. The high temperature and high pressure steam were generated and provided for the traditional brackish water desalination system. In order to enhance the sun light absorbtive capacity of the brackish water, the influence of the operation conditions including beam transmission position, abundance and size of particle from the view point of optics were studied. The transmission performance of the brackish water under boiling in an optical darkroom was tested. Furthermore, the transparency rate of the functioned brackish water under non-boiling were analyzed using experiment results. The results indicate that the transparency rate of the functioned brackish water is affected by the beam transmission position. It decreased sharply at the beginning with increasing particle abundance and decreased slowly when the particle abundance was over definite quantity. In our experiment, the particle size was chosen as 0.63 mm, 1.03 mm and 2.00 mm, respectively. The particle size in brackish water plays an important role in its transmission performance. When the particle size was about 0.63 mm, the transparency rate of the brackish water is smallest, and the attenuation rate of the transparency rate of lights reached 60.09% under the experimental conditions. While the attenuation rate of the transparency rate of lights reached 24.08% when the particle size was 2.00 mm. The luminosity on the sidewall surface also decreased with increasing particle abundance, which means the absorbtive capacity of the functioned brackish water is better than that of traditional brackish water. The trend of the variation of the theoretical calculation is the same as that of the variation of experimental results. The experimental results are also consistent with statistical results, and the R2 of the experimental analysis was 0.98694.
Number of references:26
Main heading:Water treatment
Controlled terms:Desalination - Elementary particles - Experiments - Light - Particle size - Solar energy - Transparency - Water filtration
Uncontrolled terms:Abundance - Brackish water desalinations - Functioned - High temperature and high pressure steam - Impact on the environment - Solar desalination systems - Theoretical calculations - Transmission performance
Classification code:445.1 Water Treatment Techniques - 615.2 Solar Power - 741.1 Light/Optics - 901.3 Engineering Research - 931.2 Physical Properties of Gases, Liquids and Solids - 931.3 Atomic and Molecular Physics
DOI:10.3969/j.issn.1002-6819.2013.24.027
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248517
Title:Experiment on wireless sensors network based on double cluster head clustering routing algorithm of energy heterogeneous in paddy field
Authors:Lei, Gang (1); Wang, Weixing (1); Sun, Baoxia (1); Zheng, Shaoxiong (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou 510642, China; (2) Key Laboratory of Key Technology for South Agricultural Machinery and Equipment, Ministry of Education, South China Agricultural University, Guangzhou 510642, China; (3) Guangdong Polytechnic College, Guangzhou 510520, China
Corresponding author:Wang, W.(weixing@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:139-146
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Aiming at the problem that the cluster head nodes died beforehand because of the exhaustion of energy in the cluster structure of at wireless sensor network, an energy-heterogeneous double cluster head routing algorithm (EHDCA) was proposed, which was suitable for a hybrid antenna networking communication test in the field. First, the threshold value was determined through evaluating the average remaining energy of the whole network, which was intended for selecting the main cluster head nodes (MCH). Then, the rest of the nodes in a cluster were chosen according to acknowledged signal strength acquired from other nodes' response to MCH. Lastly, a node that had the maximum energy in the cluster was selected to be the vice cluster head node (VCH). The VCH was responsible for collecting and fusing the data of member nodes. It shared energy consumption of the MCH and decreased the death probability of MCH. EHDCA was simulated in an energy-heterogeneous network, in which the average node energy was equal to that of homogeneous network where all nodes energy was kept the same in balance. Simulation results showed, compared to LEACH in an energy-homogeneous network, that the network stable period increased by 12.1% respectively in an energy-heterogeneous network. Directional antenna (model: TDJ-0825BKM1) associated with omni-directional antenna were applied for conducting hybrid antenna communication research in field while the wireless communication module used an RF905 RF chip to test the coverage of a directional horizontal antenna. Network simulation on the basis of the coverage of a directional horizontal antenna results showed that, compared to LEACH, LEACH-E, DEEC and EADC, the network stable period ratio was increased by 46%, 47%, 58%, and 11%.
Number of references:30
Main heading:Sensor nodes
Controlled terms:Algorithms - Communication - Computer simulation - Directive antennas - Energy utilization - Heterogeneous networks - Leaching - Routing algorithms - Wireless sensor networks - Wireless telecommunication systems
Uncontrolled terms:Cluster head - Communication research - Energy heterogeneous - Hybrid antenna - Omni-directional antenna - Routing - Wireless communications - Wireless sensors networks
Classification code:732 Control Devices - 723.5 Computer Applications - 723 Computer Software, Data Handling and Applications - 722 Computer Systems and Equipment - 716 Telecommunication; Radar, Radio and Television - 533.1 Ore Treatment - 525.3 Energy Utilization
DOI:10.3969/j.issn.1002-6819.2013.24.019
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248507
Title:Simulation analysis of flow characteristics of Jatropha curcas oil in diesel injector
Authors:Cui, Huifeng (1); Luo, Fuqiang (1); Wang, Ziyu (2); Dong, Shaofeng (1)
Author affiliation:(1) School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang 212013, China; (2) China North Engine Research Institute, Datong 037036, China
Corresponding author:Luo, F.(luofq@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:63-71
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The formation and development process of fuel spray has a great influence on fuel atomization, fuel evaporation, fuel-air mixing, and combustion, which can further influence the properties of a diesel engine. The atomization process and its quality are affected not only by the mutual friction between the fuel spray and ambient air, but also by the flow behavior in the nozzle orifice such as the cavitation effect and the turbulent flow among which the flow disturbance induced by the cavitation is the first important factor effecting the atomization of fuel spray. A lot of research studies on an alternative fuel, Jatropha curcas oil (JCO), for diesel fuel have been carried out by both domestic and international scholars with the focus mainly on the preparation methods, and physical and chemical properties as well as the performance and the pollutant emissions of a diesel engine fueled with JCO. Nevertheless, the issues related to a systematic study of the cavitation flow and the spray outflow characteristics, which have a great influence on the injection and atomization of JCO, are seldom reported. In the present paper, a three-dimensional gas-liquid two-phase model of cavitation flow was developed, which took the influence of injection conditions on fuel viscosity, fuel density, and bubble number density into consideration. After the validity of the model was verified, a three-dimensional numerical simulation that was about the influences of injection pressure, injection back pressure and fuel temperature on the cavitation flow of JCO in a diesel nozzle was carried out. The results showed that: the mean flow velocity at outlet (MFVO) and the mass flow rate is enhanced gradually with the increment of injection pressure, and the discharge coefficient decreases simultaneously. However, the cavitation effect does not change significantly. The injection backpressure has little influence on the flow characteristics of JCO in the diesel nozzle. MFVO, mass flow rate, and discharge coefficient raise remarkably with the increment of JCO temperature, and at the same time, the cavitation effect is significantly enhanced. The cavitation effect and MFVO of JCO are lower than those of diesel fuel under the same injection condition, but whether the mass flow rate and the discharge coefficient of JCO are higher than those of diesel fuel also depends on the fuel temperature. The results obtained indicate that the increment of JCO temperature will remarkably enhance the cavitation effect, strengthen the flow disturbance, and improve MFVO and the cycle fuel injection quantity, which are beneficial for the fuel injection, atomization, and the performance of a diesel engine. The research can provide references for in-depth analysis on the working process of diesel engine fueled with JCO.
Number of references:25
Main heading:Diesel engines
Controlled terms:Alternative fuels - Atomization - Biofuels - Cavitation - Computer simulation - Diesel fuels - Fluidity - Fuel injection - Nozzles - Pipe flow - Spray nozzles - Three dimensional
Uncontrolled terms:Bubble number densities - Cycle fuel injection quantities - Discharge coefficients - Flow charac-teristics - Injection conditions - Jatropha Curcas oil - Physical and chemical properties - Three-dimensional numerical simulations
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 802.3 Chemical Operations - 723.5 Computer Applications - 631.1.1 Liquid Dynamics - 631.1 Fluid Flow, General - 612.2 Diesel Engines - 524 Solid Fuels - 523 Liquid Fuels - 521 Fuel Combustion and Flame Research
DOI:10.3969/j.issn.1002-6819.2013.24.009
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248508
Title:Numerical simulation on modal of large submersible axial-flow pump rotor
Authors:Shi, Weidong (1); Guo, Yanlei (1); Zhang, Desheng (1); Meng, Fanyou (2); Jiang, Wenjun (2)
Author affiliation:(1) Technology and Research Center of Fluid Machinery Engineering, Jiangsu University, Zhenjiang 212013, China; (2) Jiangsu Yatai Pump and Valve Co. Ltd, Taizhou 225400, China
Corresponding author:Shi, W.(wdshi@ujs.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:72-78
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Based on method of fluid-solid coupling, a model of the large submersible axial-flow pump (1600QZ55-1100) rotating component which contains an impeller, axis and hub was studied by means of a second development of UDF and coupling WORKBENCH with APDL command. It obtained the natural frequencies and mode of vibration of a rotating component in a vacuum with pre-stress was considered, and pre-stress was not considered. Furthermore, it also achieved the natural frequencies and mode of vibration of a rotating component in water with pre-stress considered. All the above were studied in a steady condition. However, the axial-flow pump works in an unsteady condition in fact. This paper studied the effect of an unsteady condition on the structure mode too. The result showed that the natural frequencies of considering pre-stress in a steady condition are larger than those of not considering pre-stress, especially that the natural frequency corresponding to a longitudinal mode of vibration is 20% larger in a condition of considering pre-stress, and the natural frequencies of a structure in water decrease by about 10% compared with those in a vacuum. On the other hand, the first-order natural frequency in unsteady condition changes periodically with time, yet the range of that is so narrow that it could be regarded as steady. The narrow range of the first-order natural frequency that results from the range of the force on a structure in an unsteady condition is pretty narrow, compared with the huge axial force. It proved that the result in a steady condition was correct. The reason that caused the natural frequencies to increase with pre-stress considered in a vacuum is that the force on the structure results in the stress stiffening of structure, so that the stiffness of the structure in all directions is enhanced, especially the huge axial force on the structure lead to the natural frequencies increasing by 20% corresponding to a longitudinal mode of vibration. The effect of the damping of water was the main reason that makes the natural frequencies of a structure in water decrease, which also reduces the value of the amplitude of all modes of vibration at the same time. Thereby, the modal distribution consistent with the actual situation could be obtained, which can provide a theoretical basis for improving system performance and further study for more complicated dynamics analysis and fatigue analysis.
Number of references:22
Main heading:Natural frequencies
Controlled terms:Axial flow - Modal analysis - Pumps - Rotors - Submersibles - Vacuum
Uncontrolled terms:Fluid-solid coupling - Longitudinal modes - Mode of vibration - Natural frequencies and modes - Second development - Steady conditions - Stress stiffening - Unsteady conditions
Classification code:921 Mathematics - 711.1 Electromagnetic Waves in Different Media - 674.1 Small Marine Craft - 633 Vacuum Technology - 631.1 Fluid Flow, General - 618.2 Pumps - 601.2 Machine Components
DOI:10.3969/j.issn.1002-6819.2013.24.010
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248515
Title:Pollution loads variation of agricultural source in upstream of Huairou Reservoir
Authors:Zhang, Weiwei (1); Li, Hong (1); Sun, Danfeng (2); Zhou, Liandi (1)
Author affiliation:(1) Institute of System Comprehensive Development, Beijing Academy of Agriculture and Forest Science, Beijing 100097, China; (2) College of Resources and Environmental Sciences, China Agricultural University, Beijing 100193, China
Corresponding author:Li, H.(lihsdf@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:124-131
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Increased nutrient (i. e., nitrogen and phosphorus) concentrations have been observed in the surface water bodies inmany counties. Agricultural non-point source (NPS) pollution has been identified as one of the most important factors in causing water quality deterioration. To control NPS pollution effectively, it is necessary to quantifying agricultural pollution loads and understanding contribution of the pollution sources. Furthermore, watershed-based analysis can provide scientific basis for agricultural practices and water pollution control. In this paper, the general export coefficient model was used to estimate the loads of total nitrogen (TN) and total phosphorus (TP) from the upper Lianghuai basin of Huairou Reservoir for year 2000 and 2011. The model results showed that the total nitrogen and total phosphorus loads in 2000 were mainly contributed from the farmland planting, livestock and poultry breeding., while aquatic agriculture mainly contributed the total nitrogen and total phosphorus loads in 2011.Agricultural nitrogen and phosphorus loads increased in the study area during two year period. The nitrogen load increased from 454.029 ton in 2000 to 485.961 ton in 2011, while phosphorus load increased from 51.014 ton in 2000 to 58.437 ton in 2011. The nitrogen and phosphorus loads from aquatic agriculture took account of the largest percentage among the agricultural pollution sources. The agricultural land use and industrial structure changes caused nitrogen and phosphorus loads changed from 2000 to 2011 in the study basin. In the future, the corresponding control measures are recommended according to different pollution sources in order to reducing their pollution discharges. Moreover, recycling economy pattern is encouraged to achieve the resource utilization and reuse of planting, breeding and rural life waste.
Number of references:32
Main heading:Pollution
Controlled terms:Agriculture - Models - Nitrogen - Phosphorus - River pollution - Surface waters - Water pollution control - Water quality - Watersheds
Uncontrolled terms:Agricultural pollution - Agricultural practices - Export coefficient models - Industrial structures - Nitrogen and phosphorus - Non-point source pollution - Resource utilizations - Water quality deterioration
Classification code:902.1 Engineering Graphics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 804 Chemical Products Generally - 454.2 Environmental Impact and Protection - 453.2 Water Pollution Control - 453 Water Pollution - 444.1 Surface Water
DOI:10.3969/j.issn.1002-6819.2013.24.017
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248509
Title:Analysis on out-of-roundness of low-head hydrogenerator under operation condition
Authors:Li, Zhenggui (1); Yang, Fengyu (1); Si, Guolei (3); Wang, Dehong (2); Deng, Yuxuan (1); Ma, Biao (1)
Author affiliation:(1) Institute of Energy and Power Engineering Lanzhou University of Technology, Lanzhou 730050, China; (2) Gansu Chaijiaxia Hydropower Station, Lanzhou 730065, China; (3) Fenghuo Machinery Factory, Chengdu 611130, China
Corresponding author:Li, Z.(lzhgui@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:79-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Low-head hydro-generators are an internationally recognized renewable green clean energy with the most advantages in China. At present, hydro-generators operating in the countryside with electrified wire netting are generally a horizontal structure with a low-head and small capacity. With the increase of low head hydroelectric generating turbines operating in the river, there still exist different problems in the various links. However, a relatively short history of the design, manufacture, installation, operation and maintenance of low head hydraulic turbines may easily lead to the increase of roundness deformation of the generator in operation. Field technicians usually do nothing more that an analysis of the structure and operating conditions. Moreover, the research by experts and scholars the problems are limited. The generator related accidents are more common both at home and abroad, and have become more and more serious. This paper studied this problem on the practical side. The existence of gravity and centrifugal force during operation creates eccentricity and an uneven air gap in the low head hydraulic generator, forming an unbalanced magnetic field which leads to an unbalanced magnetic pull. The effect of the alternating load finally not only creates an increase of the roundness deformation of the generator stator and the rotor, but also creates a torsional bending of the generator, increasing vibrations and possibly a generator fatal "friction" accident. This paper took unit # 1 at the Chaijiaxia hydropower station on the Yellow River as the research object through the parameter analysis of the generator eccentricity and the air gap, the exciting current in steady and transient states and the loss of excitation in generator, and the generator temperature, including the change law of unbalanced electromagnetic force, axis changes, torsional bending, vibrations, and the roundness deformation. On this basis, by studying the generator magnetic force, torque, analytical equations of coupled bending, and torsional vibrations of the rotor, this paper described, the cause of the change of the generator roundness deformation through the qualitative analysis of the gas gap, unbalanced magnetic pull, as well as the generator operation stability under the condition of static eccentricity, eccentric motion and eccentric vibrations. It undertook a quantitative analysis of the variation of the generator air-gap and magnetic pull that influenced the roundness deformation, and the cause that produced vibration, overheating, and fatigue in the load condition via finite element calculation. According to this research conclusion, running measures have been put forward to make the generator run in its optimal condition, and the obvious effect has been obtained. Moreover, the theoretical basis, the analysis methods, and operation mode are provided to solve the problem of the roundness deformation in a low head hydraulic generator.
Number of references:31
Main heading:Rotors (windings)
Controlled terms:Accidents - Bending (deformation) - Finite element method - Hydroelectric generators - Instruments - Magnetic devices - Magnetic fields - Problem solving - Research - Vibrations (mechanical)
Uncontrolled terms:Hydraulic generator - Low head - Operation safety - Out of roundness - Unbalanced magnetic pull
Classification code:921 Mathematics - 921.6 Numerical Methods - 931.1 Mechanics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 914.1 Accidents and Accident Prevention - 421 Strength of Building Materials; Mechanical Properties - 611.1 Hydroelectric Power Plants - 701.2 Magnetism: Basic Concepts and Phenomena - 704 Electric Components and Equipment - 704.1 Electric Components - 714 Electronic Components and Tubes - 901.3 Engineering Research
DOI:10.3969/j.issn.1002-6819.2013.24.011
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248523
Title:Vision-based parameters extraction of seedlings for grafting robot
Authors:He, Leiying (1); Cai, Liyuan (1); Wu, Chuanyu (1)
Author affiliation:(1) Faculty of Mechanical Engineering and Automation, Zhejiang Sci-Tech University, Hangzhou 310018, China
Corresponding author:Wu, C.(cywu@zstu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:190-195
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:To achieve full automation of a grafting robot for fruits and vegetables, this paper presented a machine vision system for restoring the cotyledons of seedlings and extracting their parameters by ellipse fitting. Overlooking images of seedlings were captured by a gray camera. After doing a fast median filter, bright areas composed of cotyledons were segmented by an auto-threshold binarization algorithm with Otsu. Moreover, their contours could be easily found by an edge trace algorithm. Each corner representing the intersection of two different cotyledons was detected by finding the local maximum of the curvature in the contours. Under the constraints of distance and arc length, two corners which belong to the same two cotyledons were made a pair. Thus, all contour segments belonging to the same cotyledon could be retrieved. To restore the shape of the cotyledon, its contour was parameterized by a fitting ellipse. Through combining two parameterized cotyledons, the parameters of seedlings including growth direction, growth point, and size were extracted. Furthermore, the cells in which the seedlings were planted were determined by arraying all growth points. In a grafting operation, the growth direction and growth point can be used to assist the manipulator to fetch the seedling accurately, and the size of a cotyledon can provide some information for making the best correspondences between rootstocks and scions. One example showed that the proposed method can achieve good performance even if the cotyledons overlap each other. The errors from an ellipse fitting defined as the least absolute distance from initial points to the ellipse were calculated. Moreover, their means and standard derivation were mostly near 0.5 pixels, which indicated that the ellipse can represent the shape of the cotyledon well. Exceptionally, several ellipses with large errors were not accurate due to the fuzzy contour. The reason is that the segmented bright area was mixed in with some non-cotyledon region. The final test showed that 461 seedlings were identified and positioned in all 473 seedlings, and its rate reached 97.5%, which meets the requirement of robot grafting. There are two main reasons why some seedlings were missed. First, the bright stem and the cotyledon may be overlapped in the overlooking image because of the bending stem, and may bring in an additional corner of the contour. Secondly, when the place the seedling is living is kept away from the center of tray or the two neighbor cotyledons are too close, the cell where the seedling was planted cannot be found.
Number of references:21
Main heading:Seed
Controlled terms:Algorithms - Computer vision - Edge detection - Errors - Extraction - Geometry - Grafting (chemical) - Parameter extraction - Restoration - Robots
Uncontrolled terms:Absolute distance - Binarization algorithm - Corner extractions - Ellipse fitting - Fruits and vegetables - Growth directions - Machine vision systems - Parameters extraction
Classification code:921 Mathematics - 821.4 Agricultural Products - 802.3 Chemical Operations - 802.2 Chemical Reactions - 922 Statistical Methods - 731.5 Robotics - 716 Telecommunication; Radar, Radio and Television - 409 Civil Engineering, General - 402 Buildings and Towers - 723.5 Computer Applications
DOI:10.3969/j.issn.1002-6819.2013.24.025
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248513
Title:GIS-based flood disaster risk assessment in Wuling Mountain Region
Authors:Yin, Jie (1); Pei, Zhiyuan (1); Chen, Xiwei (1); Yi, Xiangsheng (1); Sun, Li (1)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Beijing 100125, China
Corresponding author:Pei, Z.(peizhiyuan@tom.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:110-117
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Flood disasters happen frequently in recent years and causes great loss in parts of China. Wuling Mountain Region is one of fourteen Continuous Extremely Poverty Areas (CEPA), across three provinces and one municipality city (respectively is Hubei Province, Hunan Province, Guizhou Province and Chongqing City). The region is characterized with large minority population and wide poor people distribution, where annual precipitation is between 730 and 1260 mm, and flood disasters occur frequently. The flood disaster threatens the communities usually, which pushes the people in worse condition. Based on the natural and social conditions, the resistance of economic development is relatively large, for the outstanding phenomenon of "disaster induced poverty and disaster recurrent poverty" in this region. In this paper, on the basis of disaster system theory, flood disaster risk indicator system was established in the varied topography and poor people wide distribution mountainous area. The flood disaster risk indicator system divided into three main components, namely hazard indicator (H), sensitivity indicator (S) and vulnerability indicator (V). In the indicator system, precipitation was driving factor of flood, belonged to hazard indicator (H), terrain, river system, soil and resistance ability were factors for flood redistribution, belonged to sensitivity indicator (S), population, crops and buildings were belonged to vulnerability indicator (V). According to geographical information system (GIS), some counties in the middle eastern of study area had higher hazard level for strong rainfall. The hazard environment was complex involving seven factors, and the result showed the higher sensitive area was in band from northeastern to southwestern. And the vulnerability was in different pattern from hazard and sensitivity, the higher sensitive areas were located in eastern and western, and the lower areas was seated on the middle part of the region. Applying risk assessment model based on flood disaster hazard, environment sensitivity, resilient society vulnerabilities, different hazard bearing bodies' and integrated risks caused by flood disaster were computed in Wuling Mountain Region. The results indicated that the study area risk level was relatively lower, and the total area of low and lower risk levels was up to 85.63%. The high risk areas were in bands distribution from northeast to southwest in the study area. There are three bands from southeast to northwest, respectively is southeast region (including Lianyuan City, Lengshuijiang City, Xinhua County, Longhui County, Shaoyang County, Dongkou County and Wugang City), central strip region (including Shimen County-Cili County-Yuanling County-Luxi County-Chenxi County-Xupu County-Mayang County-Zhijiang County), and northwest region (including Fengdu County and Shizhu County northwestern). This result was similar to the previous study on the scale of whole country. The pressures of regional poverty alleviation and disaster reduction are large because of the regional feature, although total flood disaster risk level is comparatively low. The results of this study will be useful in the poverty alleviation practice and regional natural disaster risk management. The next important work will focus on action mechanism between natural disaster risk and regional poverty, which will be an interesting achievement for guidance the poverty reduction, medium-term/long-term programs and regional development.
Number of references:27
Main heading:Floods
Controlled terms:Disasters - Geographic information systems - Hazards - Landforms - Regional planning - Risk assessment
Uncontrolled terms:Economic development - Flood disaster - Mountain regions - Natural disaster risk - Natural disaster risk management - Regional development - Risk assessment models - Vulnerability indicators
Classification code:403.2 Regional Planning and Development - 481.1 Geology - 723.3 Database Systems - 914.1 Accidents and Accident Prevention
DOI:10.3969/j.issn.1002-6819.2013.24.015
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248500
Title:Improved design of straw-cutting type threshing mechanism of full-feeding combine harvester
Authors:Chen, Yulun (1); Ding, Weimin (1); Fang, Zhichao (1); He, Chunxia (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Key Laboratory of Intelligent Agricultural Equipment, Nanjing 210031, China
Corresponding author:Ding, W.(wmding@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:11-16
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The exhaust of a full-feeding type combine harvester after threshing is composed of relatively longer straw, which results in difficulty for later stage field operations of scattering the straw to the cropland uniformly, and fully incorporating the straw into the soil. Longer straw is also easy to wind on the shaft of a rotary tiller in the process of cultivation, stuffing the openers of a sowing machine in the process of growing. As longer straw was not fully mixed with soil, the porosity of the soil became high, water loss became quick, and the seeds were to be sowed into the straw, not into the soil as well. Thus, the crop will be dried to death in the summer or be frozen to death in the winter, for the crop could not root steadily in the soil. If the currently applied straw shredding device is taken into concern, one has to face with the additional complexity of the structure, and the limited universality of the system, because there is no sufficient space to arrange the transmission system of the shredding device, and the shredding device can not be modified and fixed easily on the straw outlet of the machine. In order to facilitate the later operation of threshed straw returning back to the cropland by collecting the straw into the ditch, a flow-guiding shredder was developed and the shredder was assembled in the cover of a modified 4LL-1.8 full-feeding combine harvester based on analyzing the original structure of the threshing device. The operating performance of the modified threshing mechanism was tested. The field trial proved that, after threshing, the modified threshing unit could shred the straw effectively. The length of the cut straw can be adjusted by changing the angle, α, between straw-cutting knife and the axis of the roller. Moreover, the length of the shredded straw turned shorter with the increasing of the angle, α, gradually. The changing trend of the length of threshed straw was consistent with the theoretical analysis. If α was kept no less than 60°, the length of the shredded straw was controlled within a length of 200 mm, and at least 90% of the straw feeding into a ditch was attainable. The modified threshing device will both satisfy the straw-cutting and ditch-feeding demand for the machine design and allow the subsequent field work to be operable. The proposed construction of the threshing mechanism is simple in design but effective in working, which can be used as a reference for other similar designs.
Number of references:25
Main heading:Feeding
Controlled terms:Crops - Cultivation - Design - Harvesters - Machine design - Soils - Straw
Uncontrolled terms:Combine harvesters - Field operation - Full-feeding - Improved designs - Operating performance - Original structures - Thresher - Transmission systems
Classification code:408 Structural Design - 483.1 Soils and Soil Mechanics - 601 Mechanical Design - 691.2 Materials Handling Methods - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2013.24.002
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248536
Title:Effect of temperature and time fluctuations on quality changes of iced Trichiurus haumela in cold chain logistics process
Authors:Yang, Shengping (1); Xie, Jing (1); Gao, Zhili (1); Qian, Yunfang (1); Shi, Jianbing (1)
Author affiliation:(1) Shanghai Engineering Research Center of Aquatic Product Processing and Preservation, College of Food Science and Technology, Shanghai Ocean University, Shanghai 201306, China
Corresponding author:Xie, J.(jxie@shou.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:302-310
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The purpose of this paper is to study the effect of temperature-time fluctuations on the quality of fishery products in cold chain logistic by investigating the quality changes of hair-tail fish (Trichiurushaumela). A real-time monitoring of temperature and the melt rate of ice during the process was conducted instantly. To simulate the portage and transportation process, the trunks containing the control fish samples (lot I) were exposed in a condition of 20°C for 2 h and then stored at 2°C during the rest period of process, while the trunks of the experimental group (lot II) were exposed at 20°C for 24 h. The quality changes of hair-tail fish were also investigated including sensory analysis, K value, total viable counts (TVC), Enterobacteriaceae counts, total volatile basic nitrogen (TVB-N), trimethylamine nitrogen (TMA-N), pH and TBA values. It was found that the foam trunks could retard the growth of the inside temperature effectively, which rose only by 5°C when the trunks were exposed at 20°C for 24 h. The crushed ice was also helpful to maintain the temperature but the ice melted quickly. The average melting rate of ice in the trunks was 56.54 mL/h, and the volume proportion of melted water to total ice-water was about 25.79% after 24 h. An obvious decrease in sensory quality of fish samples was observed during the broken-off cold chain transportation, as the abdomen of the fish was bloated when the fish was immersed in the melted water. The K value of the two samples increased continually because of the degradation of ATP indicating the loss in freshness. Consequentially, the bacterial counts of lot II increased to 5.64 lg (CFU/g) after 24 h, one log cycle higher than that of the control samples. Significant differences of Enterobacteriaceae counts between lot I and lot II were also found in this study. The contents of TVB-N and TMA-N and the values of pH and TBA rose as the transportation period increased. There were significant differences of these quality indicators between the two fish samples generally after 24 h of transportation process. The TVB-N content of lot II was about 2.7 mg/100 g lower than that of lot I, and the TMA-N content of lot II was about 11 mg/100g lower at the end of process. pH value of lot II reached 7.8, while it maintained at around 7.3 in lot II. These results demonstrated that lot II was less spoiled than lot I. The lower TBA values of lot II in comparison with lot I indicating that the fish sample of lot II had a lower lipid-oxidation level. According to the quality limitation of Chinese National Standards, the selling shelf-life of fish on ice was cut-off by about 2-3 days if they were transported in a broken-off cold chain. This study revealed the effect of the broken-off of the cold chain on the quality and shelf-life of hair-tail fish, which indicated that the trunks of aquatic foods should be kept at low temperature as long as possible before on sale and the melted water should be drained away in time.
Number of references:30
Main heading:Quality control
Controlled terms:Fish - Ice - Logistics - Nitrogen - Sensory perception - Temperature
Uncontrolled terms:Chinese national standard - Cold chain - Effect of temperature - Iced Trichiurus haumela - Time - Total volatile basic nitrogens - Transportation period - Transportation process
Classification code:913.3 Quality Assurance and Control - 913 Production Planning and Control; Manufacturing - 912 Industrial Engineering and Management - 822 Food Technology - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 804 Chemical Products Generally - 641.1 Thermodynamics - 471 Marine Science and Oceanography - 461.4 Ergonomics and Human Factors Engineering - 461 Bioengineering and Biology - 443 Meteorology
DOI:10.3969/j.issn.1002-6819.2013.24.039
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248534
Title:Application of biospeckle on analysis of agricultural products quality
Authors:Hu, Menghan (1); Dong, Qingli (1); Liu, Baolin (1); Tu, Kang (2); Song, Xiaoyan (1)
Author affiliation:(1) School of Medical Instrument and Food Engineering, University of Shanghai for Science and Technology, Shanghai 200093, China; (2) College of Food Science and Technology, Nanjing Agricultural University, Nanjing 210095, China
Corresponding author:Dong, Q.(qdong@usst.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:284-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The equipment structures, data processing methods and research progresses in the agricultural products quality detection of the biospeckle technology were reviewed in this paper. Biospeckle technology was one of the optical non-destructive testing technologies, which was low-cost, fast, real-time and could achieve qualitative/quantitative measurement. Because the biospeckle activity had the close relationships with the physiological properties of the agricultural products such as the cytoplasmic streaming and organelles size, the physicochemical indicators could be assessed by this technology, including the peel thickness, ripeness, acidity, soluble solid content, starch content, water content and respiratory rate, etc. According to the previous researches, the biospeckle technology was firstly divided into the static and dynamic biospeckle method in this review. The static biospeckle method had been widely used over the past few decades, because the image features could be obtained by simple image processing techniques. Although the image processing speed was fast, the number and accuracy of detectable indicators were limited by the static biospeckle method. In term of dynamic biospeckle method, the video processing speed would hinder the development and extension of this technology, and hence, it could be applied for the point-of-sale quality evaluation at present. The use of advanced hardware such as the high speed camera and improvement of video processing and analysis software might promote the application of dynamic biospeckle method in on-line quality detection. Furthermore, the measuring equipments should be improved to make the laser source more stable, and several suggestions were proposed in this review such as using the polarizers in the light path or choosing different equipment layouts (stereo or planer optical path arrangement) on basis of various tested samples and conditions. In addition, the principle of measurement needs understanding in the molecular level to realize standardization and commercialization. In this respect, the combination use of the biospeckle technology and microscopic technique was suggested to explain the light transmission rules in the agricultural products. It was believed that the understanding of the light transmission rules would improve the detection accuracy. Also, the comparison of fixed and zoom lens used in biospeckle experiments was analyzed qualitatively by biospeckle test platform in our lab, and the obtained result demonstrated that the camera with zoom lens could acquire clearer image and much more information. This review might have benefit for the biospeckle technology development in the agricultural products field.
Number of references:67
Main heading:Quality control
Controlled terms:Agricultural products - Application programs - Equipment - Image processing - Light transmission - Nondestructive examination - Optical data processing - Technology - Video signal processing
Uncontrolled terms:Biospeckle - Data processing methods - Laser speckle - Microscopic techniques - Non destructive testing - Physiological properties - Simple image processing techniques - Technology development
Classification code:901 Engineering Profession - 821.4 Agricultural Products - 741 Light, Optics and Optical Devices - 913.3 Quality Assurance and Control - 723.2 Data Processing and Image Processing - 716.4 Television Systems and Equipment - 421 Strength of Building Materials; Mechanical Properties - 723 Computer Software, Data Handling and Applications
DOI:10.3969/j.issn.1002-6819.2013.24.037
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248526
Title:Development of dynamic model of cornstalk bale combustion
Authors:Liu, Enhai (1); Liu, Shengyong (1); Bai, Bing (1); Chen, Peiran (2)
Author affiliation:(1) Key Laboratory of Renewable Energy, Henan Agricultural University, Zhengzhou 450002, China; (2) School of Automation Science and Electrical Engineering, Beijing University of Aeronautics and Astronautics, Beijing 100191, China
Corresponding author:Liu, S.(liushy@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:218-226
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The differential thermal experiments of entire cornstalk bale combustion were designed according to the characteristics of cornstalk bale combustion. A dynamic model of the combustion process was developed through analyzing thermo-gravimetric data collected from the combustion of cornstalk bales under different air supply temperature (18°C-90°C) and different air flow with excess air coefficientαwith 0.7, 1.1 or 1.5. The pyrolysis kinetic parameters modeled include activation energy and frequency factor. The activation energy and frequency factor adopted from Kissinger method were 94.4 kJ/mol and 70.6 kJ/mol, 1.2×106 and 3.3×106 respectively. Their correlation coefficient was greater than 0.99. Model predicted results and measured data were essentially identical. The model performed well. In this experiment the cornstalk bale combustion process were divided as three parts: endothermic and dehydration, precipitation of volatile and the combustion reaction, fixed carbon combustion reaction. The initial temperature of the straw of the volatile gradually decreased with increasing heating rate, volatilization is releasing slowly. First, it reached in kinetic region, gradually into transition region, finally in diffusion region with volatilization combustion. Final temperature of the precipitation of volatile and the peak temperature of the weight loss rate deviated to the side of high temperature. The result showed that the TG and DTG characteristic curve of cornstalk bale combustion were similar overall. The burning velocity changed rapidly in the early period of combustion, it slowed down gradually in the middle period and finally ended towards a stable condition. According to the combustion experiments of cornstalk bales, the higher the combustion temperature was, the faster volatilization separated out. The dominant factors that influenced the combustion efficiency are the combustion temperature and air flow. The controlled temperature combustion under rational air distribution and dissolution velocity of volatiles were uniform and moderate, combustion was relatively stable. The combustion dynamic model provides a theory basis for the design, operation and reconstruction of biomass bale and combustion equipment. It is expected that biomass bale combustion technology will be transferred into real world production.
Number of references:31
Main heading:Combustion
Controlled terms:Activation energy - Air - Air quality - Dynamic models - Experiments - Fueling - Models - Straw
Uncontrolled terms:Combustion characteristics - Combustion dynamic model - Combustion efficiencies - Combustion experiments - Combustion temperatures - Controlled temperature - Correlation coefficient - Excess air coefficient
Classification code:921 Mathematics - 902.1 Engineering Graphics - 901.3 Engineering Research - 821.5 Agricultural Wastes - 804 Chemical Products Generally - 801.4 Physical Chemistry - 524 Solid Fuels - 523 Liquid Fuels - 522 Gas Fuels - 521.1 Fuel Combustion - 443.1 Atmospheric Properties
DOI:10.3969/j.issn.1002-6819.2013.24.029
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248514
Title:Effect of freeze-thaw cycles on available nitrogen and phosphorus, enzymatic activities of typical cultivated soil
Authors:Wang, Feng (1); Zhu, Yan (1); Chen, Si (1); Zhang, Keqiang (1); Bai, Hongling (1); Yao, Hu (1)
Author affiliation:(1) Institute of Agro-environmental Protection, Ministry of Agriculture of China, Tianjin 300191, China; (2) Key Laboratory of Production environment and Agro-product Safety of Ministry of Agriculture, Tianjin Key Laboratory of Agro-environment and Food Safety, Tianjin 300191, China
Corresponding author:Zhang, K.(kqzhang68@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:118-123
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The phenomenon of freezing-thawing is very prevalent in China, especially in northwest, northeast China and North China Plain. Soil chemical properties may be affected in freeze-thaw process, and then crop growing in next year. To explore transformation of nitrogen (N), phosphorous (P) and enzyme activity affected by freeze-thaw cycles, 3 typical cultivated soils (black soil, loess and fluvo-aquic soil from northeast, northwest and North China Plain) were collected and frozen for 72 hour at two temperature (-20°C and -10°C), and thawed at 24°C for 24 hour as one freeze-thaw cycles. These three kinds of soils were all subjected to two freeze-thaw cycles. And soil NO<inf>3</inf>--N, NH<inf>4</inf> -N, available phosphorous and two enzyme activities were determined before soil frozen at each cycle. The results showed that NO<inf>3</inf>--N contents in 3 kinds of soil increased sharply after the second freeze-thaw cycle, and NO<inf>3</inf>--N increments were ranked as Loess > fluvo-aquic soil > black soil. NO<inf>3</inf>--N contents increased significantly in Loess and fluvo-aquic soil compared with control. Soil NH<inf>4</inf> -N contents decreased in all 3 soil samples with freeze-thaw cycle increasing, and NH<inf>4</inf> -N decrement followed as black soil > loess and fluvo-aquic soil. Whereas NH<inf>4</inf> -N content in black soil dropped significantly by four times compared to control after second freeze-thaw cycle. The content of available phosphorus significantly increased (P>0.05) in black soil after two freeze-thaw cycle in both two frozen temperatures, But freeze-thaw cycle had no significant affected to loess and fluvo-aquic soil compared to control respectively. The soil catalase activity increased significantly with freeze-thaw cycle increasing in all three soil samples at -10°C. While, a little decrease appeared after second freeze-thaw cycle at -20°C. In contrary, the urease activity generally decreased in all three soils after the first freeze-thaw cycle. But great decrement of urease activity occured after the second freeze-thaw cycle. In conclusion, compared with freeze-thaw, freezing temperature had a slight influence on availability nutrients and enzyme activity in cultivated soils. NO<inf>3</inf>--N increments in loess and fluvo-aquic soil after freezing should be considered to crop fertilization management, which is also necessary to be combined with the precipitation value, crops species and other soil environmental factors with different actual conditions.
Number of references:28
Main heading:Freezing
Controlled terms:Crops - Cultivation - Enzyme activity - Frozen soils - Nitrogen - Phosphorus - Plants (botany) - Sediments - Soil mechanics - Soil surveys - Soils - Thawing
Uncontrolled terms:Available phosphorus - Crop fertilization - Environmental factors - Enzymatic activities - Freeze-thaw - Freeze-thaw process - Freezing temperatures - Soil chemical property
Classification code:822.2 Food Processing Operations - 821.4 Agricultural Products - 821.3 Agricultural Methods - 804 Chemical Products Generally - 483.1 Soils and Soil Mechanics - 483 Soil Mechanics and Foundations - 461.9 Biology
DOI:10.3969/j.issn.1002-6819.2013.24.016
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248535
Title:Experimental study of cross flow drying of expanded feed particles
Authors:Wang, Zhenhua (1); Yang, Deyong (1); Ding, Tian (1); Wang, Meiling (2); Zhang, Jiwei (2); Liu, Xiangdong (1)
Author affiliation:(1) College of Engineering, China Agricultural University, Beijing 100083, China; (2) Muyang Group, Yangzhou 225127, China
Corresponding author:Liu, X.(xdliu@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:293-301
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Extrusion process is a widely used processing technology in feed industry. Expanded feed is popularly applied in aquaculture and animal cultivation. However, the moisture content of the freshly expanded feed is big for safe storage. Mostly, the feed is dried by cross flow drying method. Therefore, in order to study the cross flow drying behavior of expanded feed particles in fixed bed, experiments were performed in a laboratorial scale dryer. Effect of ventilation method, hot air temperature and bed thickness on drying kinetics and drying uniformity was discussed. Thin-layer drying, one-way drying and reversing airflow direction drying were investigated in digital tunnel dryer and domestic drying test bed respectively. Hot air temperature was set at 90 and 100°C, while the bed thickness was set at 5, 7.5, 10, 15 and 20 cm. The moisture content and temperature of the feed, air temperature and relative humidity at outlet were determined by oven (DHG-9140A, Jinghong, Shanghai, China), electronic balance (FB224, Hengping, Shanghai, China), infrared thermometer (Raynger ST6L, Reytek, USA) and humidity and temperature meter (HM70, Vaisala, Finland) respectively and the moisture content and moisture uniformity curves were plotted with the obtained data. The results showed that the reversing ventilation drying couldn't increase the drying rate, but it could balance the moisture distribution during cross flow drying, because the expanded feed at the bottom layer of the bed was dried faster at the beginning, but moisture absorption emerged at the bottom layer after airflow direction was first reversed. The moisture content increased and the relative humidity decreased from 95% to 60% at the first reversal at 100°C, and the reduced moisture was detained in the feed. Thus, local over-drying was avoided and the feed could be dried uniformly by changing the airflow directions constantly. Higher hot air temperature could generate local over-drying easier, so the difference of moisture content between the top layer and the bottom layer would be bigger, which could lead to the larger moisture nonuniformity. A superficial constant drying rate stage was observed at a critical bed thickness (10 cm) in one-way drying, but for a bigger bed thickness, an increasing drying rate stage was observed. The reason was that moisture absorption was observed at the top layer at the beginning of drying at bed thickness of 15 and 20 cm and then moisture content increased slightly. When the drying front reached the top layer, feed particles with bigger moisture content were dried and the drying rate was bigger. But the superficial constant drying rate was smaller than thin layer constant drying rate. The thin layer drying rate was 0.034 kg/(kg min) at the temperature of 60°C, while the superficial constant drying rate was 0.0275 kg/(kg min) at the temperature of 100°C.
Number of references:28
Main heading:Drying
Controlled terms:Agricultural products - Atmospheric temperature - Dryers (equipment) - Electronic scales - Equipment testing - Experiments - Moisture - Moisture determination - Plants (botany) - Ventilation
Uncontrolled terms:Electronic balances - Hot air temperature - Humidity and temperatures - Infrared thermometers - Moisture distribution - Moisture nonuniformity - Processing technologies - Uniformity
Classification code:944.2 Moisture Measurements - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 901.3 Engineering Research - 821.4 Agricultural Products - 802.1 Chemical Plants and Equipment - 715 Electronic Equipment, General Purpose and Industrial - 643.5 Ventilation - 642.1 Process Heating - 461.9 Biology - 443.1 Atmospheric Properties
DOI:10.3969/j.issn.1002-6819.2013.24.038
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248528
Title:Improving emulsifying performance of bio-oil/diesel by emulsion and co-emulsifier
Authors:Tan, Wenying (1); Xu, Yong (1); Wang, Shuyang (2)
Author affiliation:(1) Material Science and Engineering of Northeast Forestry University, Harbin 150040, China; (2) Engineering Centre for Biomass Energy Technology of Northeast Forestry University, Harbin 150040, China
Corresponding author:Wang, S.(twy2088@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:235-243
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Bio-oil is easy to extract, transport and storage. It is a kind of potential clean and renewable energy and can be used as fuel in oil burning boiler and turbine engine directly. Furthermore, Bio-oil can be blended with gasoline, diesel in certain percentage through using advanced emulsion process to produce clean, environment-friendly bio-oil/disel mixed emulsification fuel. It not only improves the calorific value of fuel and the combustion performance, the emulsified oil also can be directly applied to ordinary diesel engine with or without modification. Bio-oil is a mixture with high percentage of water and acid, the stability of the emulsion products is an important factor for its large-scale application. Meanwhile, the choice of emulsifier and auxiliary emulsifier is important for the stability of bio-oil. In this paper, the impact of emulsifier types, HLB value, dosage of emulsifier, types of auxiliary emulsifier and dosage of auxiliary emulsifier on the stability of the emulsified bio-oil/diesel oil were studied using non-ionic compound surfactants. The stability of the emulsified oil and absorbance ratio K was used as observation object at the macroscopic level. the average particle size of emulsified oil and the distribution of emulsified oil droplets were used as observation objects at the micro level. The experimental results showed that the stabilization time of the emulsified oil reached up to 17 days using Tween80 and Span80 as mixed emulsifier when B-oil content was blended with 5%, 90% of diesel fuel, and 5% of emulsifier. The absorbance ratio K was 1.11, which means the stability is best with the particle size of 1.56 um in the microscopic observation. The best HLB value range was 5.0-5.8, the peak curve is higher on the particle size distribution, and there was more number of small oil droplets. The highest peak and the most number of droplets were reached when the HLB value was set as 5.4.As the HLB value increase, the oil droplets number was reduced and the particle size become bigger. Within a certain range, the stability time is proportional to the content of emulsifier. Since the price of emulsifier is higher than Bio-oil, we recommend that the suitable amount of emulsifier is 5% during the emulsified oil production. The stability time of the emulsified oil increased 7 or 8 days using n-octanol and methanol as co-emulsifier. The stability time of emulsified oil can be increased using co-emulsifier. Adding methanol as auxiliary emulsifier is more economically effective. The best emulsified oil stability was reached when the methanol content was set as 20%. The stability of the emulsified oil was decreased with increased Bio-oil content. The emulsified oil is experienced with stratification, flocculation, coalescence and demulsification process. It is our expectation that this study will assist in support of industrial development and application of the bio-oil.
Number of references:25
Main heading:Emulsification
Controlled terms:Biofuels - Convergence of numerical methods - Diesel engines - Diesel fuels - Drops - Methanol - Particle size - Particle size analysis - Stability
Uncontrolled terms:Average particle size - Bio oil - Combustion performance - Emulsifier co-emulsifier - Environment friendly - Industrial development - Large-scale applications - Microscopic observations
Classification code:951 Materials Science - 931 Classical Physics; Quantum Theory; Relativity - 921.6 Numerical Methods - 804.1 Organic Compounds - 961 Systems Science - 802.3 Chemical Operations - 612.2 Diesel Engines - 524 Solid Fuels - 523 Liquid Fuels - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2013.24.031
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248516
Title:Stereo matching algorithm based on improved graph cuts for high spatial resolution satellite stereo pair
Authors:Wang, Ruirui (1); Shi, Wei (3); Huang, Huaguo (1)
Author affiliation:(1) Key Laboratory for Silviculture and Conservation, Ministry of Education, Beijing Forestry University, Beijing 100083, China; (2) Center of 3S Technology and Mapping, College of Forestry, Beijing Forestry University, Beijing 100083, China; (3) Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China
Corresponding author:Wang, R.(wangruigis@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:132-138
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Many objects have clear contour and texture in the high spatial resolution satellite stereo pair. Due to the elevation differences in many objects, and the existence of building shades, and the similar objects, and so on, the extraction of corresponding feature points from the high spatial resolution satellite stereo pair is difficult, which leads to a rough disparity map. Aiming at the problem, the graph cuts algorithm, which has a successful application in the computer vision field, was introduced and improved for the stereo matching. The core problem of stereo matching is to compute the optimal disparity value. Based on this rule, the graph cuts constructs the global energy function by using the disparity value of all the pixels, and transforms the problem of stereo matching to the problem of minimization of the global energy function. However, there are two problems existing in the process of stereo matching by using the traditional graph cuts for the high-resolution satellite stereo pair. The first one is that the time complexity is high; the other one is that the disparity map has a lower precision. Aiming to the aforementioned two problems, the graph cuts algorithm was improved. The improved graph cuts constructed the network and energy function based on the epipolar images, which not only lowered the time complexity, but also improved the matching precision. Based on the improved graph cuts algorithm, the global energy function was minimized, and then the minimum cut was solved and the accurate disparity map was obtained. The EROS-B satellite stereo pair was used for the experiment. Based on the equal distribution rule, 25 control points were selected for the precision check. The true disparity map was computed and compared with the disparity map created by the improved graph cuts stereo matching algorithm. By comparison and analysis on the results, two conclusions were obtained. First, compared with the traditional graph cuts algorithm, the improved graph cuts algorithm had a higher precision and an obviously lower time complexity. Second, compared with the traditional stereo matching algorithm based on the correlation coefficient, the time complexity of the improved graph cuts algorithm was a little higher, but the precision of the improved graph cuts algorithm was evidently high. This research can provide a basis for the construction of the precise digital elevation model based on the satellite stereo pair.
Number of references:27
Main heading:Image matching
Controlled terms:Algorithms - Graphic methods - Image registration - Satellites - Stereo vision
Uncontrolled terms:Comparison and analysis - Correlation coefficient - Epipolar image - Global energy - Graph cut - High spatial resolution - Stereo matching algorithm - Stereo pair
Classification code:655.2 Satellites - 723 Computer Software, Data Handling and Applications - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2013.24.018
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248521
Title:Estimation of chlorophyll contents in cotton leaves using computer vision based on gray board
Authors:Wang, Juan (1); Wei, Changzhou (1); Wang, Xiaojuan (2); Zhu, Qichao (1); Zhu, Jinlong (1); Wang, Jinxin (1)
Author affiliation:(1) Dept. of Resource and Environment, Agronomy College, Shihezi University, Shihezi 832000, China; (2) Xinjiang Tianye (Group) Co., Ltd., Shihezi 832000, China
Corresponding author:Wei, C.(changzhouwei@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:173-180
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:This paper was an attempt to develop a low-cost quick method that is easy to use to assess the chlorophyll content of cotton plants using color characteristic parameters which was adjusted by a grey board from plant images. The cotton plant images were obtained at different growth periods from different water treatments. Images were adjusted and normalized by a grey board. The second leaf from the top of a cotton stem image was taken by a CMOS digital camera. The camera lens maintained a 90 degree angle with the cotton leaf vertical to shoot. Before taking an image, the location of the camera lens and the cotton leaves was fixed, and the focal length of the lens was fixed. The gray board image was taken first every time. Using the RGB and HSB color system to split the cotton leaf color characteristics, red value (R), green values (G), blue value (B), and Hue (H), saturation (S) and brightness (Br) of the cotton image were obtained through cotton leaf analysis software that was developed by the VB. Chlorophyll content of the cotton leaf was obtained by spectrophotometer determination. The correlation analysis was set up between color characteristics parameters and chlorophyll content. The correlation coefficients between DGCI (dark green color index) or Red-Blue which were not adjusted by grey broad and cotton chlorophyll were 0.8857 or -0.8726, and they were 0.9073 or -0.9016 respectively after correction. The correlation coefficient between parameters and chlorophyll content were improved after grey board adjustment. The result showed that there were a series of color parameters combination obtained from cotton leaf images that were a highly significant linear correlation with chlorophyll content of the cotton leaf in various growth periods. The color characteristic parameters and chlorophyll content in different periods were combined, and the correlation between them was analyzed. DGCI and Red-Blue had the most highly significant linear correlation with cotton leaf chlorophyll content. Comparing the chlorophyll content prediction accuracy of DGCI or Red-Blue before and after the correction, it showed that the parameter DGCI or Red-Blue after adjustment model prediction accuracy is higher than before calibration. The prediction accuracy of DGCI is higher than Red-Blue parameters after calibration. The prediction for DGCI after adjusted was Chl. a b= 8.3265DGCI-2.0456. Between the predicted values, which were calculated by the equation, and the measured values of chlorophyll, its root mean square errors (RMSE) was 0.1200, and the relative errors (RE%) was 4.71%. The decision coefficient was 0.8812. The prediction accuracy was better. Our results demonstrated that the adjusted DGCI was the best indicator to predict cotton leaf chlorophyll content, and the prediction model was feasible for applying computer vision technology to rapidly predict cotton chlorophyll content.
Number of references:29
Main heading:Cotton
Controlled terms:Calibration - Camera lenses - Chlorophyll - Color - Computer vision - Forecasting - Mean square error - Plants (botany)
Uncontrolled terms:Chlorophyll contents - Color characteristics - Computer vision technology - Correlation analysis - Correlation coefficient - Leaf chlorophyll content - Prediction accuracy - Root mean square errors
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 921 Mathematics - 819.1 Natural Fibers - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 804.1 Organic Compounds - 741.2 Vision - 741.1 Light/Optics - 731.1 Control Systems - 461.9 Biology - 742.2 Photographic Equipment
DOI:10.3969/j.issn.1002-6819.2013.24.023
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

Accession number:20140517248506
Title:Whole-flow-passage numerical simulation and experimental validation on idling loss of hydrodynamic retarder
Authors:Huang, Jungang (1); Li, Changyou (1)
Author affiliation:(1) College of Engineering, South China Agricultural University, Guangzhou 510642, China
Corresponding author:Li, C.(lichyx@scau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:24
Issue date:December 15, 2013
Publication year:2013
Pages:56-62
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:A hydraulic retarder is a damper system which inputs mechanical energy, transforms it, and outputs heat. Due to its advantages of brake torque, smooth braking, low noise, long life and compact structure, a hydraulic retarder has been widely applied in heavy vehicles. The research and application on the hydraulic retarder abroad has been carried out earlier, and its technique is more developed. However, since the hydraulic retarder belongs to high-tech products, its high price and the technology blockade of related foreign research institutions makes it only applied to top-grade imported cars in China. At present, the hydrodynamic retarder research of related national enterprises and scientific establishments has just been started, and the level of independent research and development is still low. Therefore, to actively develop hydrodynamic retarder products with proprietary intellectual property rights, and to steadily improve its function has practical meaning for the improvement of the competiveness of the national retarder industry. When a hydraulic retarder is in braking condition, its control system will fill the working chambers of the stator and rotor with a certain amount of oil, which driven by the rotor, will generate a scroll loss effect, thereby producing braking effects on moving vehicles; in its non-braking condition, which is also called idling, the working chambers of the stator and rotor are filled with air, and similar to the braking condition, the air driven by the rotor will also generate a scroll loss effect, which is referred to as an idling loss. As shown in Figure 1, the idling loss rate directly determines the economy of a hydraulic retarder. In order to form a reliable idling loss analysis and calculation method, this paper was based on a certain type of self-developed hydrodynamic retarder prototype. This paper carried out system analysis and drew the technology schematic of idling loss, and then established the calculation model of whole-flow-passage idling loss, carried out whole-flow-passage simulation on an idling loss under 16 rotor speed conditions with the application of CFD technology, and finally proceeded with idling loss measurements with the combined bench test method which can eliminate mechanical friction loss. With the results compared and analyzed, the result of the whole-flow-passage simulation is found to be in agreement with that of the bench test, and the relative error is within 11.8%, a relatively high accuracy. Therefore, this paper proves the reliability of the whole-flow-passage simulation calculation method, and provides a reliable calculation method for the further study of the hydraulic retarder idling loss reduction.
Number of references:28
Main heading:Computer simulation
Controlled terms:Computational fluid dynamics - Experiments - Hydrodynamics - Intellectual property - Research - Rotors (windings) - Stators
Uncontrolled terms:Experimental validations - Hydrodynamic retarder - Independent research - Intellectual property rights - Mechanical friction - Research and application - Research institutions - Simulation calculation
Classification code:631.2 Hydrodynamics - 704.1 Electric Components - 705.1 Electric Machinery, General - 723.5 Computer Applications - 901.3 Engineering Research - 902.3 Legal Aspects
DOI:10.3969/j.issn.1002-6819.2013.24.008
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

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