<RECORD 1>

Accession number:  20134616980314
 
  Title:  Effect of import bend and forward turbolator on performance of centrifugal pump
  Authors:  Yan, Yu1 Email author yanyu0404@126.com; Lu, Xiaofeng1 Email author xflu@njut.edu.cn; Zhu, Xiaolei1 
  Author affiliation:  1 College of Mechanical and Power Engineering, Nanjing University of Technology, Nanjing 211816, China 
  Corresponding author:  Lu, X. (xflu@njut.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  74-81
  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 an important kind of fluid conveying equipment, a centrifugal pump is widely used in modern industrial production, but the issue of its low operation efficiency was not solved effectively, and at the same time a large amount of energy is consumed by a centrifugal pump every year, a huge burden has been brought on economic development. In order to improve the operation performance of a centrifugal pump, with the idea of improving the inlet flow field of a centrifugal pump, three kinds of bend forward turbolators were designed. First of all, the blade and central body of the turbolator and the centrifugal pump were modeled by Pro/E, and then meshed in Gambit. Finally, the whole flow field of a centrifugal pump with an imported bend was simulated under the design conditions by using a MRF model which was supported by Fluent, both the standard k-Ε turbulence model and the SIMPLE method were adopted to solve the Navier-Stokes equations for incompressible flow. According to the simulation results under different import lines, it was concluded that both the turning radius (R) of the 90 degree elbow and entrance straight tube length (L) of the bend had an influence on operation efficiency, and that the former was more obvious. The efficiency of a centrifugal pump can be effectively improved by increasing R, and it will be first increased and then decreased with the increasing L, the maximum efficiency can be reached when L=D, so the operation efficiency can be improved by an appropriate increase of R and L, the maximal efficiency can be up to 81.98%. After installing a turbolator, the inlet flow state of a pump got a considerable improvement, the efficiency of centrifugal pump was improved, and from all kinds of turbolator, the CJ-3406 had the most obvious effect, it can increase the efficiency by 4%. This indicates that the efficiency can be better improved when the aerofoil curve changes gently. With a turbolator, the work space of a centrifugal pump can be saved, so the turbolator can be better served for actual production. At the same time, the speed direction is perpendicular to the impeller inlet when the fluid flow through the pipe elbow. Centrifugal pump inlet flow can be more uniform and axisymmetric flow can be involved in the import which ensures the uniform distribution of pump inlet pressure. What is more, both the pressure and velocity of the import are improved, so the performance of anti-cavitation of a centrifugal pump is enhanced, the NPSHa can be increased by 0.2 m with the turbolator of 3307b. This article provides a new train of thought for improving the inlet line and the operation performance of a centrifugal pump in actual production.
  Number of references:  30
  Main heading:  Centrifugal pumps 
  Controlled terms:  Computer simulation  -  Efficiency  -  Flow fields  -  Incompressible flow  -  Inlet flow  -  Navier Stokes equations  -  Turbulence models 
  Uncontrolled terms:  Conveying equipment  -  Economic development  -  Industrial production  -  Maximum Efficiency  -  Operation efficiencies  -  Operation performance  -  Turbolator  -  Uniform distribution 
  Classification code:  618.2 Pumps -  631 Fluid Flow -  723.5 Computer Applications -  913.1 Production Engineering
  DOI:  10.3969/j.issn.1002-6819.2013.21.011
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 2>

Accession number:  20134616980332
 
  Title:  Nutrient release characteristics of multi-layer coated urea and their mathematical simulation
  Authors:  Yu, Jiangang1, 2 Email author yujg1112@scau.edu.cn; Liu, Fang1, 2; Fan, Xiaolin1, 2 Email author xlfan@scau.edu.cn 
  Author affiliation:  1 College of Nature Resource and Environment Science, South China Agriculture University, Guangzhou 510642, China 
   2 Univ. Res. Center of Environmental Friendly Fertilizer Eng. and Technology in Guangdong Province, 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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  220-225
  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 double-factors randomized block design was applied to find out the nutrient release characteristics of multi-layer coated urea, which were coated with water soluble resin (a mixture of vinyl chloride acrylate and vinylidene chloride acrylate) as the primary coating material and C9 modified petroleum resin as the subsidiary material. So 12 coated ureas were prepared as 12 treatments that were made through a fluid-coating technique, that were accompanied with a factor of modified C9 petroleum resin as the inner protection layer with 3 levels of 5, 10, and 15 g per square meter of the kernel fertilizer surface, and another factor of water soluble resin as the middle coated layer with 4 levels of 30, 40, 50, and 60 g per square meter of the kernel fertilizer surface. In addition all coated urea had an outer layer of 10 g C9 modified petroleum resin per square meter of the kernelfertilizer surface. After that, nitrogen release from coated urea was tested, which were in static pure water under a constant temperature of 25°C with fertilizer and water ratio of 1 vs 5, and further a Richards function was applied to describe nitrogen release, then the result was tested and parameters calculated were used to evaluate the release characteristics of coated urea with different coating materials. Therefore, the aim was to offer some theoretical foundation for the improvement and development of manufacture technology of multi-layer coated urea and its scientific application. The results were as follows. First, it was estimated that there existed 10 sigmoid curves in 12 nutrient release curves through the shape parameter of the Richards function, it was deduced that their release curve may be sigmoid that was coated with water soluble resin and modified C9 petroleum resin. Secondly, it found that the modified C9 petroleum resin inner layer mainly induced action on the curve shape, and the curve shape would tend to sigmoid when the inner layer added from 5 to 10 g/m2. Meanwhile the time of maximum nutrient release speed was delayed by 22.6, 49.3, 74.9, and 39.4 d. Then it increased to 15 g/m2 further, the shape of curve was not varied that the time of max nutrient release speed had not moved or only was brought forward lightly. Thirdly, it showed that a water soluble resin coating layer played a significant role in the nutrient release rate, the longevity was significantly increased with the thickness of middle coated layer added, with that the coating material from 30 added to 60 g/m2 by a step of 10 g/m2, and the range of longevity was definitely between 75.0 and 287.1 d. In summary, the water soluble resin coated urea with a protection layer of water-insoluble material was achievable to release nutrients according to sigmoid. And then multi-layer coated urea could be made with a inner layer of 5 to 10 g/m2 C9 modified petroleum resin, a outer layer of 10 g/m2 C9 modified petroleum resin, and with from 30 to 60 g/m2 water soluble resin coating material, with the products achieving longevity of from 75.0 to 287.1 d, and those products complied with the relevant national standards of controlled release fertilizer.
  Number of references:  26
  Main heading:  Nutrients 
  Controlled terms:  Chlorine compounds  -  Coatings  -  Computer simulation  -  Fertilizers  -  Metabolism  -  Models  -  Nitrogen  -  Plating  -  Resins  -  Surfaces  -  Urea  -  Urea fertilizers 
  Uncontrolled terms:  Coating material  -  Constant temperature  -  Controlled-release fertilizers  -  Manufacture technology  -  Mathematical simulations  -  Release characteristics  -  Scientific applications  -  Theoretical foundations 
  Classification code:  931 Classical Physics; Quantum Theory; Relativity -  902.1 Engineering Graphics -  821.2 Agricultural Chemicals -  815.1.1 Organic Polymers -  951 Materials Science -  804 Chemical Products Generally -  539.3 Metal Plating -  539 Metals Corrosion and Protection; Metal Plating -  461.9 Biology -  723.5 Computer Applications
  DOI:  10.3969/j.issn.1002-6819.2013.20.029
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 3>

Accession number:  20134616980338
 
  Title:  Fast identification of watermelon seed variety using near infrared hyperspectral imaging technology
  Authors:  Zhang, Chu1 Email author chuzh@zju.edu.cn; Liu, Fei1; Kong, Wenwen1; Zhang, Hailiang1, 2; He, Yong1 Email author yhe@zju.edu.cn 
  Author affiliation:  1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310058, China 
   2 School of Mechatronics Engineering, East China Jiaotong University, Nanchang 330013, China 
  Corresponding author:  He, Y. (yhe@zju.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  270-277
  Language:  Chinese
  ISSN:  10026819 
  CODEN:  NGOXEO 
  Document type:  Journal article (JA)
  Publisher:  Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
  Abstract:  Watermelon seed variety selection plays a vital role in watermelon planting, and the variety of watermelon seeds directly affect the yield and quality of watermelons. In this study, we aimed to identify the cultivars of watermelon seeds by using a novel, rapid, non-invasive, and low cost technique named hyperspectral imaging. 121 samples of four different cultivars of watermelon seeds were investigated, and a near-infrared hyperspectral imaging system (874-1734 nm with 256 bands) was established to acquire the hyperspectral images of the samples. A region of interest (ROI) with 15×15 pixels of the hyperspectral image of each sample was defined, and the average reflectance spectrum of the ROI were extracted. To remove the absolute noises of the spectra, only the spectral range 1042-1646 nm was used for analysis, and to reduce the noises existed in spectral range 1042-1646 nm, the extracted 121 reflectance spectra were preprocessed by Savitzky-Golay smoothing (SG), Empirical Mode Decomposition (EMD), and Wavelet Transform (WT) methods. The preprocessed spectra were then used to select sensitive wavelengths by Successive Projections Algorithm (SPA) and Genetic Algorithm-partial least squares (GA-PLS) methods. Different numbers of sensitive wavelengths were selected by different variable selection methods with different preprocessing methods. 24, 16, and 15 sensitive wavelengths were selected by SPA with spectra preprocessed by SG, EMD, and WT, respectively. Moreover, 38, 33. and 32 sensitive wavelengths were selected by GA-PLS with spectra preprocessed by SG, EMD. and WT, respectively. Partial least squares-discriminant analysis (PLS-DA) was used to build discriminant models with the full spectra, and back-propagation neural network (BPNN) and extreme learning machine (ELM) were applied to build discriminant models with the selected wavelength variables. A PLS-DA model with spectra preprocessed by EMD obtained the best identification rate among all PLS-DA models, with an identification rate of 91.57% in the calibration set and 78.95% in the prediction set. SPA-BPNN models showed relatively worse results than GA-PLS-BPNN models with the same spectral preprocessing methods. The SG-GA-PLS-BPNN model obtained the best performance among all BPNN models, with an identification rate of 92.77% in the calibration set and 86.84% in the prediction set. Compared with the PLS-DA models and the BPNN models, ELM models obtained the best results. All ELM models obtained an identification rate over 90% in the calibration set and the prediction set, and the SG-SPA-ELM model, SG-GA-PLS-ELM model, and WT-SPA-ELM model obtained the identification rate of 100% of calibration and prediction. The overall results showed that BPNN and ELM models performed better than PLS-DA models, and the ELM models with the selected wavelengths based on SG preprocessed spectra obtained the best results, with 100% classification accuracy for both the calibration set and the prediction set. The SG preprocessing method showed the best performance in all PLS-DA, BPNN, and ELM models. The results indicated that it was feasible to use near-infrared hyperspectral imaging to identify the watermelon seed varieties, and near-infrared hyperspectral imaging provided an alternate way of rapid identification of watermelon seed variety. ELM, as a single hidden layer feed-forward network, was an effective classification method in watermelon seed cultivar identification. Moreover, the results in this paper showed the great potential of hyperspectral imaging in the seed industry for on-line identification of seed cultivars and detection of the seed quality parameters.
  Number of references:  30
  Main heading:  Calibration 
  Controlled terms:  Discriminant analysis  -  Forecasting  -  Genetic algorithms  -  Independent component analysis  -  Infrared devices  -  Knowledge acquisition  -  Learning systems  -  Least squares approximations  -  Near infrared spectroscopy  -  Neural networks  -  Reflection  -  Signal processing  -  Wavelength 
  Uncontrolled terms:  Back-propagation neural networks  -  Extreme learning machine  -  Genetic algorithm-partial least squares  -  Imaging processing  -  Near-infrared hyperspectral imaging  -  Partial least squares-discriminant analysis  -  Successive projections algorithm  -  Successive projections algorithms (SPA) 
  Classification code:  943 Mechanical and Miscellaneous Measuring Instruments -  942 Electric and Electronic Measuring Instruments -  941 Acoustical and Optical Measuring Instruments -  922 Statistical Methods -  921.6 Numerical Methods -  944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments -  921 Mathematics -  723.4 Artificial Intelligence -  723 Computer Software, Data Handling and Applications -  716.1 Information Theory and Signal Processing -  711 Electromagnetic Waves -  741.3 Optical Devices and Systems
  DOI:  10.3969/j.issn.1002-6819.2013.20.035
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 4>

Accession number:  20134616980339
 
  Title:  Experiment of mechanized gutting for typical small marine fish
  Authors:  Chen, Qingyu1, 2, 3 Email author chenqingyu@fmiri.ac.cn; Shen, Jian1, 2, 3; Ouyang, Jie1, 2, 3; Ding, Jianle2; Zhong, Junsheng4; Zhang, Jingfeng2; Hu, Xiaoliang1, 2, 3 
  Author affiliation:  1 Key Laboratory of Fishery Equipment and Engineering, Ministry of Agriculture, Shanghai 200092, China 
   2 Fishery Machinery and Instrument Research Institute, Chinese Academy of Fishery Sciences, Shanghai 200092, China 
   3 National Research and Development Branch Centre for Aquatic Product Processing Equipment, Shanghai 200092, China 
   4 Fisheries and Life Science Shanghai Ocean University, Shanghai 201306, China 
  Corresponding author:  Chen, Q. (chenqingyu@fmiri.ac.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  278-285
  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:  An experimental study on mechanized gutting for small marine fish was conducted, faced with equipment shortages for the pre-processing of small marine fish. The test platform of fish gutting was established. Abyssal searobin (Lepidotrigla abyssalis), crossbarred lizardfish (Synodus macrops), and little yellow croaker (Pseudosciaena polyactis) were selected as the typical representative fish. The following experiments were conducted for comparing the gutting effects and sensory quality of processed small marine fish: the two types of arrangement patterns for fish belly cutting and gutting, two types of cutting disc configuration, four types of gutting wheel structure configuration, and the rotation direction and rotation speed changes of the cutting disc and gutting wheel, and their various matching combinations with the linear velocity of the pinch belt. The test results showed that the lower setting type cutting and gutting devices combined with the converse cutting of a high rotating toothless disc knife and converse gutting of low rotating form-copying special-shaped toothed gutting wheel are suitable to all the three typical small marine fish. A triangular profile toothed gutting wheel or Trapezoidal profile toothed gutting wheel combined with a converse gutting processing method are also suitable for flat belly fish such as Abyssal searobin (Lepidotrigla abyssalis) and the fish which have a laterally compressed body such as little yellow croaker (Pseudosciaena polyactis). The productivity of a mechanized processing method is as 8-12 times as much as the productivity of a manual processing method. The 100% gut removal rate and the quality effect of almost zero fish body damage can be achieved for some small species. The processing order of mechanized gutting for small marine fish is: head cutting-orienting and orderly feeding-pinch belt positioning and conveying-disc knife rotary cutting fish belly-pinch belt positioning and conveying-opening fish belly-gutting wheel scrapings off fish viscera-pinch belt positioning and conveying-and gutted fish conveyed to washing. In general, the above mentioned species of small marine fish are landed together, and their size and body characteristics are greatly different, so their pre-processing is difficult and needs a heavy workload. However, the manual gutting processing replaced by the mechanical gutting processing can be achieved through proper size grading and species sorting, and the development of a general small-scale fish gutting device. This research can provide the guidance for the design of mechanized cutting and gutting equipment for small marine fish.
  Number of references:  27
  Main heading:  Fish 
  Controlled terms:  Cutting  -  Cutting equipment  -  Experiments  -  Grading  -  Machine tools  -  Productivity  -  Sensory perception  -  Wheels 
  Uncontrolled terms:  Belly cutting device  -  Gutting device  -  Manual processing  -  Processing method  -  Rotation directions  -  Sensory qualities  -  Structure configuration  -  Triangular profiles 
  Classification code:  913.3 Quality Assurance and Control -  913.1 Production Engineering -  901.3 Engineering Research -  822 Food Technology -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  604.1 Metal Cutting -  603.1 Machine Tools, General -  601.2 Machine Components -  471 Marine Science and Oceanography -  461.4 Ergonomics and Human Factors Engineering -  461 Bioengineering and Biology
  DOI:  10.3969/j.issn.1002-6819.2013.20.036
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 5>

Accession number:  20134616980337
 
  Title:  Discrimination of mildewed oats using electronic nose and optimization of its sensor array
  Authors:  Yin, Fangyuan1, 2 Email author ffyy-yin@126.com; Huang, Jie1, 2; Wang, Minmin1, 2; Zheng, Haixia1, 2; Yang, Yue1, 2; Chen, Jing1, 2; Zeng, Xiaoyan1, 2; Tong, Chunxia1, 2; Wang, Lüye1, 2; Jiang, Yan1, 2; Shen, Feng1, 2; Hui, Guohua1, 2 Email author ghui@zjgsu.edu.cn 
  Author affiliation:  1 College of Food Science and Biotechnology, Zhejiang Gongshang University, Hangzhou 310035, China 
   2 Food Safety Key Laboratory of Zhejiang Province, Hangzhou 310035, China 
  Corresponding author:  Hui, G. (ghui@zjgsu.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  263-269
  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:  Oats (Avena Sativa L.) are one of the important food crops. It contains some rich nutrients. Oats easily gets mildew affected by environmental factors during storage, which is getting to be one of problems in the food safety field. As one artificial olfactory analysis method, the electronic nose technique is widely applied in crop quality detecting fields. This technique utilizes a gas sensor array to imitate a human's olfactory system. The detecting signals measured by a gas sensor array is discriminated and recognized by an artificial pattern recognition method. Then the species of the detecting objectives can be determined. In this paper, electronic nose system was utilized to discriminate mildewed oat samples. The diagram includes three main parts: data acquisition and transmitting unit, sensor array and the chamber unit, and power and gas supply unit. The sensor array consisted of eight semiconductor gas sensors. Polytetrafluorethylene (PTFE) material was utilized to fabricate the chamber. Each sensor room was separated, which helped to eliminate the cross-influence of the gas flow. At the same time, gas sensor array optimization was also studied. 25 g of oat samples were weighed and placed into an experimental container. The container was tightly sealed with parafilm. 40 samples were prepared. All samples were stored under room temperature and standard atmospheric pressure. In order to accelerate the mildew procedure of the samples, 4 mL deionized water was sprayed on all samples every day. 10 samples were randomly selected in an electronic nose measurement. The measurement time of each oat sample was 45 s. The experiments lasted for five days. The measurement data was measured and transmitted to the computer. The stochastic resonance had three principal parts: a weak input signal, a non-linear bistable system, and an additional dose of external Gaussian white noise. The experimental data was coupled into a non-linear bistable stochastic resonance model. Stepping external Gaussian stimulating white noise was utilized to modulate the stochastic resonance system for resonance generation. Finally, stochastic resonance signal-to-noise ratio (SNR) was calculated and exported as signal-to-noise ratio curves. Eigen values of systematic output signal-to-noise ratio were selected for principal component analysis (PCA). The total degree of contribution of the first principal component and the second principal component was 96.43%. In order to improve the mildewed oat discrimination rate, sensor loadings analysis was used to evaluate the contribution rate of all gas sensors. The optimized gas sensor array included S1, S2, S3, S4, S5, S6 and S7. After an optimization procedure, the total degree of contribution of the first principal component and the second principal component was 99.31%. These results demonstrated that an electronic nose system presents a discriminating ability for mildewed oat samples. Sensor array optimization based loadings analysis improved the discriminating rate. The proposed method is promising in the crop quality and safety analysis field.
  Number of references:  31
  Main heading:  Principal component analysis 
  Controlled terms:  Atmospheric pressure  -  Chemical sensors  -  Circuit resonance  -  Containers  -  Crops  -  Deionized water  -  Digital storage  -  Fungi  -  Magnetic resonance  -  Nonlinear analysis  -  Optimization  -  Sensors  -  Sensory aids  -  Signal detection  -  Signal to noise ratio  -  White noise 
  Uncontrolled terms:  Bistable stochastic resonance  -  Electronic NOSE  -  First principal components  -  Mildew oat  -  Output signal-to-noise ratios  -  Pattern recognition method  -  Semiconductor gas sensors  -  Stochastic resonances 
  Classification code:  722.1 Data Storage, Equipment and Techniques -  801 Chemistry -  801.2 Biochemistry -  821.4 Agricultural Products -  921 Mathematics -  921.5 Optimization Techniques -  922.2 Mathematical Statistics -  716.1 Information Theory and Signal Processing -  443.1 Atmospheric Properties -  445.1 Water Treatment Techniques -  461.5 Rehabilitation Engineering and Assistive Technology -  691 Bulk Handling and Unit Loads -  694 Packaging -  701.2 Magnetism: Basic Concepts and Phenomena -  703.1.1 Electric Network Analysis
  DOI:  10.3969/j.issn.1002-6819.2013.20.034
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 6>

Accession number:  20134616980340
 
  Title:  Photoelectrocatalytic degradation of ethylene with TiO2 modified by 60Co γ-ray irradiation
  Authors:  Zheng, Senhong1 Email author senhong310@163.com; Ye, Shengying1 Email author yesy@scau.edu.cn; Huang, Xun1; Shen, Shengwen1 
  Author affiliation:  1 College of Food Science, South China Agricultural University, Guangzhou 510642, China 
  Corresponding author:  Ye, S. (yesy@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  286-292
  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:  Horticultural products are abundant in China. However, a large amount of them were deteriorated due to the lack of appropriate storage and transport technology, resulting in a huge waste. Ethylene gas is one of the main reasons which cause the deterioration of horticultural products in storage. Nanometer TiO2 photoelectrocatalysis technology is a new technique developed in recently. TiO2 under UV light, can degrade organics such as ethylene, so it provides a potentially effective method for keeping free products. However, in practical applications, the mutual composite happens easily, which shorts the lives of the carriers and limits the application of TiO2. The only solution for this problem is to decrease the compositing rate of photoinduced electrons and the holes by modifying the nanometer-sized TiO2. Developing modified method is also a hot topic of researchers here in China and abroad. 60Co-γ ray irradiation reduction technique can modify TiO2 and make it more activity for the catalytic degradation of organics. In order to investigate the effect of TiO2 irradiated by 60Co-γ ray and loaded with activated carbon fibers (ACF), on photoelectrocatalytic degradation of ethylene in the environment of cold storage, the TiO2/ACF photoelecrorcatalysis materials was deposited with nano-Ag (Ag-TiO2/ACF) and irradiated by 60Co-γ ray. The effects of 60Co-γ ray irradiation modified TiO2 (10, 15, 20, 25, 30, 40 kGy) on the photoelectrocatalytic degradation rate of ethylene were investigated in a simulated cold storage environment for horticultural product. X-ray diffractometer and X-ray photoelectron spectroscopy were used to characterize the prepared TiO2. Results from X-ray diffraction showed that: the crystal size has reduced. The percent of anatase decreased from 84.97% in pure TiO2 to 82.98% in TiO2 treated with a 40 kGy irradiation dose. Result of X-ray photoelectron spectroscopy indicated that the amount of Ti3 , hydroxyl oxygen which have better catalytic activity increased after irradiation. The percentage of Ti3 in total Ti element rose from barely detected to 3.1%. The hydroxyl oxygen increased from 18.83% to 35.8%. Both X-ray diffraction and X-ray photoelectron spectroscopy results favored the separation rate of electron-hole, the redox ability and catalytic activity of TiO2. The apparent rate constant for photoelectrocatalysis degradation of ethylene was increased as irradiation dose increased up to 25 kGy due to the promotion of catalytic activity of TiO2. However, when the irradiation dose reached 30 kGy, the solution of TiO2 formed precipitate which reduced the specific surface of TiO2 and decreased the apparent rate constant.
  Number of references:  27
  Main heading:  Titanium dioxide 
  Controlled terms:  Catalyst activity  -  Cold storage  -  Degradation  -  Ethylene  -  Irradiation  -  Oxygen  -  Photoelectrons  -  Polyacrylonitriles  -  Radiation  -  Rate constants  -  Silver  -  Titanium  -  X ray diffraction  -  X ray photoelectron spectroscopy 
  Uncontrolled terms:  Apparent rate constant  -  Catalytic degradation  -  Horticultural products  -  Photo-electrocatalysis  -  Photoelectrocatalytic degradation  -  Photoinduced electrons  -  Transport technology  -  X ray diffractometers 
  Classification code:  815.1.1 Organic Polymers -  804 Chemical Products Generally -  802.2 Chemical Reactions -  801 Chemistry -  931.3 Atomic and Molecular Physics -  711.1 Electromagnetic Waves in Different Media -  694.4 Storage -  547.1 Precious Metals -  542.3 Titanium and Alloys -  711 Electromagnetic Waves
  DOI:  10.3969/j.issn.1002-6819.2013.20.037
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 7>

Accession number:  20134616980321
 
  Title:  Weed identification from winter rape at seedling stage based on spectrum characteristics analysis
  Authors:  Bai, Jing1 Email author 1005865199@qq.com; Xu, You2; Wei, Xinhua1 Email author wei_xh@126.com; Zhang, Jinmin1; Shen, Baoguo3 
  Author affiliation:  1 Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang 212013, China 
   2 College of Engineering, Nanjing Agricultural University, Nanjing 210031, China 
   3 Zhenjiang College of Jiangsu Union Technical Institute, Zhenjiang 212016, China 
  Corresponding author:  Wei, X. (wei_xh@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  128-134
  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:  Weeds are distributed only in patches in fields, but herbicides are applied over entire fields, thus leading to over application and unnecessary pollution. To reduce herbicide application, automatic weed recognition is being developed to treat only weed patches. Weed identification is the key point of automatic weeding, and many research studies have pointed out that the reflectance rate of green plant leaves could be used to identify the varieties. The spectral reflectance of winter rape, soil (dry and wet), and five kinds of weeds (speedwell, thistle, capsella, horseweed, and cerastium viscosum) were measured within the 350-2500 nm wavelength range by the Analytical Spectral Device (ASD) in a laboratory. Each sample was measured five times continuously, and 370×5 samples were obtained. After rejecting 2×5 samples, a total of 368×5 samples (a 278×5 training set and a 90×5 prediction set) were used for classification, and a training set and a prediction set were randomly selected. The five original spectroscopic data sets were averaged in order to eliminate random noise. First, derivative and compressing were used to pretreat the spectral data. Then, stepwise discriminant analysis was executed to reduce the redundancy spectral information and decrease the amount of calculation and improve the accuracy. Four characteristic wavelengths, 710, 755, 950, and 595 nm were selected. Then canonical discriminant analysis and Bayes discriminant analysis were applied to build recognition models for identifying these weeds, soil, and winter rape based on the four characteristic wavelengths. For the canonical discriminant function, the recognition accuracy of training was 97.84%, two miscalculations were occurred in weeds, and the recognition ratio was 97.78%. The classification accuracy of the Bayesian discriminant model was higher than the canonical discriminant model, one error was observed in the testing set and its recognition ratio was 98.89% on the condition that prior probabilities were computed from group sizes. However, its classification accuracy is the same as canonical discriminant models when prior probabilities were all equal groups. The result of the statistical analysis showed that it was feasible to use the four characteristic wavelengths as input variables to build recognition models, which was an effective approach to simplify the recognition models. Both of the canonical discriminant function and Bayesian discriminant model have a strong ability to differentiate spectra of species of plant. However, the classification accuracy of the Bayesian discriminant model was higher when prior probabilities were computed from group sizes. The research results can provide reference for the development of spectrum sensor.
  Number of references:  24
  Main heading:  Statistical tests 
  Controlled terms:  Discriminant analysis  -  Face recognition  -  Herbicides  -  Image recognition  -  Plants (botany)  -  Probability  -  Reflection  -  Spectrum analysis  -  Wavelength  -  Weed control 
  Uncontrolled terms:  Analytical spectral devices  -  Bayes discriminant analysis  -  Bayesian discriminants  -  Canonical discriminant analysis  -  Canonical discriminant function  -  Stepwise discriminant analysis  -  Weed identification  -  Winter rape 
  Classification code:  461.9 Biology -  711 Electromagnetic Waves -  716 Telecommunication; Radar, Radio and Television -  803 Chemical Agents and Basic Industrial Chemicals -  922 Statistical Methods
  DOI:  10.3969/j.issn.1002-6819.2013.20.018
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 8>

Accession number:  20134616980304
 
  Title:  Spatial-temporal characteristics and influencing factors of grain yield change in China
  Authors:  Chen, Yangfen1 Email author chenyangfen@caas.cn; Li, Xiande1 Email author lixiande@caas.cn 
  Author affiliation:  1 Institute of Agricultural Economics and Development, Chinese Academy of Agricultural Sciences, Beijing 100081, China 
  Corresponding author:  Li, X. (lixiande@caas.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 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:  Despite high attention to the stability and increase of grain production and market supply by Chinese government, grain yield in China has been undergoing a great fluctuation during the past decades, which could be a big challenge to national food security. This paper thus analyzes the spatial-temporal characteristics and influence factors of grain yield change in China since 1990 from the aspect of evolution stages and main types. Statistical indicators and spatial econometric models for panel data are introduced, which are supported by Geodata, ArcGIS, and Matlab software. It shows that the growing process of Chinese grain yield has three stages, namely stage 1990-1998, 1998-2003, and 2003-2011 respectively. Meanwhile, provinces in China can be categorized into three sets according to different supply-demand relationships, which are provinces with surplus grain (PGSG), provinces with balanced grain supply and demand (PBGSD), and provinces with insufficient grain supply (PIGS). The three separate types vary every year, with different provinces included each other. Roughly speaking, the grain production status of eastern provinces, central provinces, western provinces, and northeastern provinces is decreased, weakened, enhanced and strengthened respectively. In 2011, the PGSG, the PBGSD, and the PIGS distribute mainly at North, Middle, and South China respectively. Among all the factors that influence grain yield, the land factor has a significant positive impact, changing from strong to weak. It indicates grain production in China is increasingly dependent upon factors that contribute to per unit yield, such as technical progress, capital investment, etc. The labor factor brings an effect from positive significant to insignificant then negative significant, reflecting the change of agricultural surplus labor, rural labor structure, etc. The impact of different types of capital input varies as follows. Definitely, agricultural infrastructure investment, represented by irrigation facilities, has a strong positive effect. As a kind of labor saving capital investment, the total power of agricultural machinery brings about 'positive to negative and positive again' effect; the chemical fertilizer input, as a representative of agricultural materials, follows the law of diminishing returns to scale. Besides agricultural production factors, agricultural structure adjustment, non-agricultural industry development, and random error factors of neighboring provinces also influence the actual yield. As to the three separate types, the driving mechanism of grain yield change differs significantly, including the impact of agricultural production factors and that of macro environment. It is the mutual result of both internal law such as diminishing marginal returns and scale effect and external factors such as government regulation. Taking into account the above different driving mechanism, it will be meaningful to promote the regional division of grain production among the PGSG, the PBGSD, and the PIGS, to protect a large-scale arable land resource with a special priority to the project of arable land consolidation and protection in PGSG, to change the focal point of financial support and land consolidation to improve the efficiency of agricultural infrastructure, to solve the scarcity of agricultural labor by measures such as the cognizance of agricultural producers, and to promote agricultural mechanization with an emphasis to plain agricultural area, and which in all will help stabilize and increase grain yield in China.
  Number of references:  30
  Main heading:  Grain (agricultural product) 
  Controlled terms:  Agricultural machinery  -  Agriculture  -  Economics  -  Fertilizers  -  Food supply  -  Investments  -  Land use  -  Mammals  -  Mathematical models  -  MATLAB  -  Models  -  Stages  -  Telecommunication industry 
  Uncontrolled terms:  Agricultural mechanization  -  China  -  Influence factors  -  Panel data  -  Spatial econometric models  -  Spatial-temporal characteristics  -  Supply-demand relationships  -  Yield 
  Classification code:  921 Mathematics -  911.2 Industrial Economics -  902.1 Engineering Graphics -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  804 Chemical Products Generally -  718 Telephone Systems and Related Technologies; Line Communications -  717 Optical Communication -  716 Telecommunication; Radar, Radio and Television -  404.2 Civil Defense -  403 Urban and Regional Planning and Development -  402.2 Public Buildings
  DOI:  10.3969/j.issn.1002-6819.2013.20.001
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 9>

Accession number:  20134616980312
 
  Title:  Influence analysis of trapped oil pressure on flow pulsation in external gear pumps
  Authors:  Li, Yulong1 Email author leo-world@163.com; Tang, Mao1 
  Author affiliation:  1 Industrial Manufacturing College, Chengdu University, Chengdu 610106, China 
  Corresponding author:  Li, Y. (leo-world@163.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  60-66
  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 external gear pumps with involutes gear pairs, the existing literatures did not consider the quantitative relationship between its trapped oil pressure and its flow pulsation. Therefore, this paper aimed at seeing clearly the influence of its trapped oil pressure on its flow pulsation with no backlash value of gear pairs and a pair of symmetrical rectangle relief grooves for relieving trapped oil pressure as an example, based on the swept area method for calculating closed area and a detailed analysis of trapped oil process inherent to external gear pumps. From an accurate calculation of the changed volume in the discharge side of gear pumps along with the meshing position variables, which was the curvature radius of meshing point on meshing contour of active gear, the formula for calculating flow pulsation and the related measurable indicators such as average flow rate and flow non-uniform coefficient were derived in a ideal state and an actual state. The ideal state was that no trapped oil pressure and no leakage flow rate from discharge side of pumps to suction side was considered in the calculation of flow pulsation; and the actual state was just in contrast to the ideal state, the trapped oil pressure and the leakage flow rate must be considered in the calculation of flow pulsation; at the same time in the calculation of flow pulsation, the trapped oil pressure was performed simulating calculation by a trapped oil model which was validated to be correct and reliable in the existing literature. Then the associated indicators with the flow pulsation such as average flow rate and flow non-uniform coefficient were analyzed, and some results and conclusion were obtained. All results from the paper indicated that, relative to no relief groove in pumps, the quality of flow pulsation with a relief groove was improved in the ideal state. In an especial case, the flow rate was increased by 12.34% on average, and the flow non-uniform coefficient was reduced by 85.09%. Compared with the ideal state, the quality of the flow pulsation was decreased in the actual state, but compared with no relief groove, the quality of the flow pulsation with a relief groove was improved in the actual state, in an especial case, the flow rate was increased by 6.73% on average, and the flow non-uniform coefficient was reduced by 73.9%. At the higher speed, there was a great trapped oil pressure, but it was helpful for improving the quality of the flow pulsation. in an especial case, in which the rotating speed was 5000 revolutions per minute, the maximum peak value of the trapped oil pressure was up to 97 MPa, but the flow non-uniform coefficient was reduced by 87.61%. Finally, the trapped oil phenomenon was objectively shown to exist, so the important conclusion was summarized that the trapped oil pressure and the various related leakages from the trapped oil zone must be taken into account in the calculation of flow pulsation, and only then can the associated results with the flow pulsation be more reliable and more accurate. Although the paper was aimed at the calculation and analysis of flow pulsation with no backlash value and a pair of symmetrical rectangle relief grooves, the new method of calculating flow pulsation is suitable for any backlash value and any relief groove type.
  Number of references:  27
  Main heading:  Gear pumps 
  Controlled terms:  Flow rate  -  Leakage (fluid)  -  Models 
  Uncontrolled terms:  Accurate calculations  -  External gear pumps  -  Flow pulsation  -  Influence analysis  -  Leakage flow rate  -  Position variables  -  Revolutions per minutes  -  Trapped oil pressures 
  Classification code:  452.3 Industrial Wastes -  618.2 Pumps -  631 Fluid Flow -  902.1 Engineering Graphics
  DOI:  10.3969/j.issn.1002-6819.2013.20.009
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 10>

Accession number:  20134616980324
 
  Title:  Dynamic simulation of stem, leaf and pod development on soybean
  Authors:  Xu, Shoujun1 Email author shoujun-xu@163.com; Li, Zhigang1; Yang, Hengshan1; Chen, Chuanmei1; Zhao, Da1; Guo, Yanfeng2 
  Author affiliation:  1 College of Agronomy, Inner Mongolia University for Nationalities, Tongliao 028042, China 
   2 College of Horticulture, Shenyang Agricultural University, Shenyang 110866, China 
  Corresponding author:  Xu, S. (shoujun-xu@163.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  151-159
  Language:  Chinese
  ISSN:  10026819 
  CODEN:  NGOXEO 
  Document type:  Journal article (JA)
  Publisher:  Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
  Abstract:  Based on systematic observation, the organ morphogenesis model was established on soybeans. In the model, the time step was physiological development time, the growth process and the growth of the order of the stem, leaves and pods were measured by physiological development day, the model parameters were determined by genetic parameters, and the minimum nitrogen content, maximum nitrogen content, and critical nitrogen content were used to express the impact of nitrogen. In the model, internode potential length and potential thickness increased gradually with the increase of the number of soybeans internode, and reached a maximum at the ninth and seventh internode, and then decreased gradually. Therefore, the potential length of the ninth internode and potential thickness of the seventh internode were determined as potential genetic parameters that can calculate the other internodes' potential length and potential thickness. Because of similar leaf morphology on each internode on soybeans, this study only modeled the dynamic of the third fronds. Based on soybean morphological characteristics, this study simulated the pods which first appeared on the third internode. The results showed that the absolute prediction errors ranges of internode length, internode thickness, leaf length, leaf width, pod length, pod width, and pod thickness were 0.08-0.59, 0-0.10, 0.28-0.58, 0.31-0.39, 0.14-0.39, 0.09-0.21, 0.04-0.09 cm respectively with the root mean square errors (RMSE) being 0.25-0.28, 0.04-0.05, 0.47, 0.35-0.36, 0.24-0.39, 0.14-0.17, 0.06-0.07 cm, respectively. The model reflected a satisfactory prediction. Moisture had a greater impact on soybean organ morphogenesis. Because of the test conditions, this study did not establish a moisture influence factor model. The model establishment of water and nitrogen coupling soybean organ morphogenesis is the next research program. The models also need to be tested at a greater variety and a wider geographical scope.
  Number of references:  25
  Main heading:  Physiological models 
  Controlled terms:  Computer simulation  -  Crops  -  Mean square error  -  Models  -  Moisture  -  Morphology  -  Nitrogen  -  Physiology 
  Uncontrolled terms:  Genetic parameters  -  Moisture influence  -  Morphogenesis  -  Morphological characteristic  -  Organs  -  Root mean square errors  -  Satisfactory predictions  -  Soybean 
  Classification code:  951 Materials Science -  902.1 Engineering Graphics -  821.4 Agricultural Products -  804 Chemical Products Generally -  801.4 Physical Chemistry -  731.1 Control Systems -  723.5 Computer Applications -  461.9 Biology -  461.1 Biomedical Engineering
  DOI:  10.3969/j.issn.1002-6819.2013.20.021
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 11>

Accession number:  20134616980336
 
  Title:  Fast discriminating of purity on minced mutton using electronic tongue
  Authors:  Tian, Xiaojing1, 2 Email author smile_tian@yeah.net; Wang, Jun1 Email author jwang@zju.edu.cn; Cui, Shaoqing1 
  Author affiliation:  1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 300058, China 
   2 College of Life Science and Engineering, Northwest University for Nationalities, Lanzhou 730024, China 
  Corresponding author:  Wang, J. (jwang@zju.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  255-262
  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:  Cheaper animal protein, such as Chicken as an example, has been fraudulently used as a substitute for more expensive animal proteins, like mutton and beef. The adulteration of mutton has attracted increasing attention. It requires reliable methods for the authentication of mutton adulteration. An electronic tongue with chemically modified field-effect-transistor sensors was employed to analysis the adulteration of chicken in minced mutton. The effects of sample weight on the sensor responses of electronic tongue were studied at three different extraction solutions. Analysis of variance found that the sample weight affected the responses of the sensor significantly. With the help of Principle component analysis (PCA), the optimum experimental parameters were acquired: 15 g sample extracted by 100 mL KCl solution. The adulterated mutton was made by mixing mutton with chicken at levels of 0, 20%, 40%, 60%, 80%, and 100% by weight, respectively. With the optimum experimental parameters, 168 samples of adulterated mutton were detected, and the signals were analyzed by pattern recognition techniques to build models for classification of adulterated mutton with different content of chicken, and prediction of the content of chicken in minced mutton. With PCA, the adulterated mutton samples were grouped according to their content of chicken with good classification results, except that samples containing 80% and 100% chicken partially overlapped with each other. Better classification results were found when canonical discriminant analysis (CDA) was employed, as samples containing 80% and 100% chicken were clearly grouped and separated. Multiple linear regression (MLR) and Partial least square analysis (PLS) were employed to build the predictive model for the content of chicken adulterated into minced mutton. Both models could predict the adulteration with a high determination coefficient as high as 0.9925 and 0.9923, respectively. MLR was more effective for the prediction of chicken content. The E-nose proved to be a useful authentication method for meat adulteration detection for its efficiency and high accuracy.
  Number of references:  31
  Main heading:  Animals 
  Controlled terms:  Authentication  -  Discriminant analysis  -  Drug products  -  Electronic tongues  -  Field effect transistors  -  Forecasting  -  Linear regression  -  Meats  -  Models  -  Pattern recognition  -  Principal component analysis  -  Proteins  -  Sensors 
  Uncontrolled terms:  Adulteration of muttons  -  Canonical discriminant analysis  -  Determination coefficients  -  Experimental parameters  -  Multiple linear regressions  -  Partial least square analysis  -  Pattern recognition techniques  -  Principle component analysis 
  Classification code:  922.2 Mathematical Statistics -  814 Leather and Tanning -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  822 Food Technology -  822.3 Food Products -  902.1 Engineering Graphics -  922 Statistical Methods -  804.1 Organic Compounds -  723 Computer Software, Data Handling and Applications -  716 Telecommunication; Radar, Radio and Television -  714.2 Semiconductor Devices and Integrated Circuits -  471 Marine Science and Oceanography -  461 Bioengineering and Biology -  801 Chemistry
  DOI:  10.3969/j.issn.1002-6819.2013.20.033
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 12>

Accession number:  20134616980315
 
  Title:  Effect of irrigation and drainage engineering control on improvement of soil salinity in Tianjin
  Authors:  Wang, Xiuli1 Email author wangxiuli0614@163.com; Zhang, Fengrong1 Email author frzhang@cau.edu.cn; Wang, Yuepeng1; Feng, Ting1; Lian, Xiaojuan2; Wang, Yan2 
  Author affiliation:  1 College of Resources and Environmental Science, China Agricultural University, Beijing 100193, China 
   2 Tianjin Institute of Agricultural Resources and Environment, Tianjin 300192, China 
  Corresponding author:  Zhang, F. (frzhang@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  82-88
  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:  Since the 1950s, China has begun to develop irrigation and water conservation project construction to control the saline-alkali soil. However, there are few reports about the effect on soil salinity improvement resulting from large-scale farmland and water conservancy engineering construction. So to check the effect of irrigation and drainage engineering on soil salinity improvement action, this research took Tianjin, in which the saline-alkali soil area is wide, as an example for the discussion and analysis of the improvement effect on soil salinity of farmland and water conservancy engineering construction. This study illustrated the relationship of interaction and change between farmland and water conservancy engineering construction and soil salinity improvement from the formation environment of saline-alkali soil and salinity change based on ArcGIS9.3 and laboratory analyses. The results showed that with the constant improvement of irrigation and drainage engineering construction and facilities, during the period from 1982 to 2002, the area where the salinity soil was easy to form reduced from 65.55×104 hm2 to 54.60×104 hm2, which was down by up to the percentage of 9.96%. During the period from 1982 to 2008, the salinity soil area reduced from 49.40×104 hm2 to 32.42×104 hm2, in the meantime, 18.76% of the saline alkali soil had completed the desalinization with other areas whose soil salinity degree was also reduced substantially further. During the period from 2006 to 2010, newly increased cultivated land which originally belonged to saline-alkali land had decreased by 2.54×104 hm2, at the same time the area that the irrigation canals and ditches had exchanged into the cultivated land was up to 1.11×104 hm2. As for the profiles (0-60 cm) of the coastal saline-alkali land, more than 69.81% of the cultivated land was under the slight salinity which had a perfect drainage system. On the contrary, more than 40% of the wasteland was the solonchak, with only 14.85% of it under the slight salinity whose drainage system was relatively poorer. During the period from 1982 to 2005, the soil which was easy to undergo salinization was reduced from 65.55×104 hm2 to 49.60×104 hm2. In addition, the spatial distribution pattern of the reduced area was in accordance with the area where the degree of soil salinity had lowered. In conclusion, irrigation and water conservancy projects control the saline-alkali by decreasing the area of salinity soil, lowering the salinization rank, and reducing the newly increased cultivated land that originally belonged to saline-alkali soil by means of improving the forming environment of the saline-alkali soil. For some areas that had completed the desalinization, there were almost no floods and they were crisscrossed by irrigation canals and ditches in where the original abandoned and dilapidated irrigation canals and ditches should be classified into the reserved land resources suitable for cultivation. Through the scientific planning of irrigation and water conservancy engineering and competitive land consolidation, the cultivated lands that are cut to pieces can connect with each other and improve farmland scale, which relieves the pressure of the protection and requisition-compensation balance of cultivated land.
  Number of references:  25
  Main heading:  Soils 
  Controlled terms:  Drainage  -  Farms  -  Irrigation  -  Land use  -  Professional aspects  -  Water conservation  -  Water management 
  Uncontrolled terms:  Conservation projects  -  Constant improvement  -  Engineering constructions  -  Irrigation and water conservancies  -  Requisition-compensation balances  -  Salinity control  -  Spatial distribution patterns  -  Tianjin 
  Classification code:  901.1 Engineering Professional Aspects -  821.3 Agricultural Methods -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  502 Mines and Quarry Equipment and Operations -  483.1 Soils and Soil Mechanics -  446 Waterworks -  444 Water Resources -  442 Flood Control; Land Reclamation -  406 Highway Engineering -  403 Urban and Regional Planning and Development -  401 Bridges and Tunnels
  DOI:  10.3969/j.issn.1002-6819.2013.20.012
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 13>

Accession number:  20134616980330
 
  Title:  Model of risk analysis on site selection of biomass power plant based on stochastic robust interval method
  Authors:  Chen, Cong1 Email author chencong0420@126.com; Huang, Guohe1; Li, Yongping1; Li, Mengwen2 
  Author affiliation:  1 S and C Academy of Energy and Environmental Research, North China Electric Power University, Beijing 102206, China 
   2 Beijing Energy Conservation and Environmental Protection Center, Beijing 100029, China 
  Corresponding author:  Chen, C. (chencong0420@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  206-213
  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 transport cost of biomass fuels accounts for a large proportion of the total cost of the operation of biomass power plant. Optimizing biomass power plant site can largely mitigate the transport cost and reduce the pollutant emissions from the transportation process of biomass fuels. Therefore, it is significant to optimize the biomass power plant sit. However, the biomass power system contains many uncertainties, because that many parameters can hardly be acquired as deterministic values but expressed as interval and/or stochastic formats. For example, the supply demand of biomass fuels can be expressed as probability distributions; also, interval values can describe the uncertain parameters such as the biomass fuels price, which fluctuates between lower and upper bounds. Energy systems would become insecurity and with a high risk without considering these uncertainties. Security is a priority in the operation of biomass power plant. In this study, a stochastic robust interval model (SRIM) was developed for the biomass power plant site selection under uncertainties, through incorporating interval-parameter programming (IPP) and robust optimization (RO) within two-stage programming (TSP) framework. In SRIM, decision variables were divided into two subsets: those that must be determined before the realizations of random variables were known, and those that were determined after the realized random variables were available. The SRIM can deal with the uncertainties described in the terms of the interval values and probability distributions, moreover, it can also reflect economic penalties as corrective measures or recourse against any infeasibilities arising due to a particular realization of an uncertain event. In the SRIM modeling formulation, penalties were exercised with the recourse against any infeasibility, and robustness measures were introduced to examine the variability of the second stage costs that were above the expected levels. The SRIM was generally suitable for risk-aversive planners under high-variability conditions. The SRIM method was applied to a hypothetical case of planning biomass power plant (with installed capacity of 15 MW) site selection with considering the uncertainties. A number of solutions under different robustness levels have been generated. The obtained results can help generate desired decision alternatives that will be able to enhance the safety of biomass power system with a low system-failure risk level and particularly useful for risk-aversive decision makers in handling high-variability conditions. The result are beneficial for managers analyzing the results to gain insights into the tradeoff between system's safety and economic, and analyzing the risk of the system. The results of SRIM shows: 1) The construction number of biomass power plant is one; 2) The optimum biomass power plant is from (245, 242) km to (250, 247) km; 3) The optimum allocation scheme for each fuel purchase and storage station; 4) The system costs under different robust levels; 5) The notion of risk in stochastic programming under different robust levels. The modeling results from the RISO can help generate desired decision alternatives that will be able to not only enhance the safety of planning biomass power plant site selection with a low system-failure risk level, but also mitigate pollutant emissions from the transportation process of biomass fuels. The results are reasonable, and could provide a reference for the selection of the biomass power plant site.
  Number of references:  26
  Main heading:  Biomass 
  Controlled terms:  Compensation (personnel)  -  Costs  -  Decision making  -  Electric power generation  -  Failure (mechanical)  -  Fuel storage  -  Fuels  -  Optimization  -  Pollution  -  Power plants  -  Probability distributions  -  Random variables  -  Risks  -  Safety engineering  -  Site selection  -  Stochastic models  -  Stochastic programming  -  Stochastic systems  -  Uncertainty analysis 
  Uncontrolled terms:  Biomass power plants  -  Construction number  -  Corrective measures  -  IPP  -  Lower and upper bounds  -  RO  -  Transportation process  -  Uncertain parameters 
  Classification code:  911 Cost and Value Engineering; Industrial Economics -  912.2 Management -  912.4 Personnel -  706 Electric Transmission and Distribution -  914 Safety Engineering -  922.1 Probability Theory -  961 Systems Science -  921.5 Optimization Techniques -  615 Thermoelectric, Magnetohydrodynamic and Other Power Generators -  403 Urban and Regional Planning and Development -  421 Strength of Building Materials; Mechanical Properties -  454.2 Environmental Impact and Protection -  402 Buildings and Towers -  522 Gas Fuels -  524 Solid Fuels -  525.1 Energy Resources and Renewable Energy Issues -  523 Liquid Fuels
  DOI:  10.3969/j.issn.1002-6819.2013.20.027
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 14>

Accession number:  20134616980335
 
  Title:  Ecological risk assessment and spatial prevention tactic of land destruction in mining city
  Authors:  Chang, Qing1 Email author changqing@cau.edu.cn; Liu, Dan1; Liu, Xiaowen1 
  Author affiliation:  1 Department of Ornamental Horticulture and Landscape Architecture, College of Agriculture and Biotechnology, China Agricultural University, Beijing 100193, China 
  Corresponding author:  Chang, Q. (changqing@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  245-254
  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:  Mining is a key economic activity, and it contributes greatly to the economic growth of China. However, the consequents of land destruction, such as ecological losses and environmental pollution, could adversely damage the living environment and sustainable development of the mining area. In recent years, research studies on ecological risk assessment have been hotspots in the field of land use and environmental science for mining cities. Land destruction is recognized as the most direct and obvious source of ecological risk in mining areas. A lot of theoretical frameworks and qualification models have been built to evaluate the ecological risk of land destruction. However, it is not clear how the spatial heterogeneity of ecological risk based on land destruction can be quantitatively visualized, and what kind of targeted prevention measures should be taken in various types and grades of ecological risk, which leads to some ineffectiveness of land reclamation plans in mining cities. In this paper, a framework for ecological risk assessment and spatial prevention of land destruction for the mining city was proposed. Liaoyuan city in Jilin province, as one of the representative mining areas in China, was chosen as the case area. First, the data of land use type, land destruction type and site were vectored into a GIS platform, and an integrated GIS-based model involving the ecological sensitivity evaluation, the cumulative effect evaluation of land destruction and the evaluation of the probability of exposure to destructed lands, were constructed and applied to quantify the comprehensive value of ecological risk based on land destruction. Secondly, the spatial pattern of ecological risk of land destruction was visualized and illustrated by four zones with degrees of comprehensive value: the high-risk zone (2.5% of the total area), the medium-risk zone (17.4% of the total area), the low-risk zone (39.1% of the total area) and the risk-free zone (41% of the total area), in which the dominant risk factors were differentiated. Thirdly, the zoning matrix of land use for ecological risk prevention was built, based on risk zones, which can be used to picture the land use control zone. The zoning matrix of land use included specially-protected environmentally sensitive areas and ecological conservation areas, ecological restoration areas, ecological coordination areas, ecological reclamation areas, limited development areas, mining development areas, and urban development areas. The regionalization is consistent with the land use pattern from 2010 Urban Master Planning of Liaoyuan City, which shows this prevention-oriented land use zoning approach is effective and feasible. The study reveals that the quantitative evaluation can not only provide the spatial heterogeneity of ecological risk, but also provide an operational approach to integrate land reclamation into land use planning by making targeted risk prevention decisions. This study helps to improve the effectiveness of land reclamation and land management in the mining city.
  Number of references:  36
  Main heading:  Risk assessment 
  Controlled terms:  Ecology  -  Economics  -  Geographic information systems  -  Land reclamation  -  Land use  -  Urban growth  -  Zoning 
  Uncontrolled terms:  Ecological conservation areas  -  Ecological restoration  -  Ecological risk assessment  -  Ecological sensitivity  -  Environmental pollutions  -  Environmentally sensitive areas  -  Mining cities  -  Quantitative evaluation 
  Classification code:  403.1 Urban Planning and Development -  442.2 Land Reclamation -  454.3 Ecology and Ecosystems -  723.3 Database Systems -  922.1 Probability Theory -  971 Social Sciences
  DOI:  10.3969/j.issn.1002-6819.2013.20.032
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 15>

Accession number:  20134616980319
 
  Title:  Intercropping grasses improve soil organic carbon content and microbial community functional diversities in Chinese hickory stands
  Authors:  Wu, Jiasen1, 2 Email author jswu@zafu.edu.cn; Zhang, Jinchi1 Email author zhang8811@njfu.edu.cn; Qian, Jinfang3; Huang, Jianqin3 
  Author affiliation:  1 College of Forest Resources and Environment, Nanjing Forestry University, Nanjing 210037, China 
   2 Zhejiang Provincial Key Laboratory of Carbon Cycling in Forest Ecosystems and Carbon Sequestration, Zhejiang A and F University, Lin'an 311300, China 
   3 The Nurturing Station for the State Key Laboratory of Subtropical Silviculture, Zhejiang A and F University, Lin'an 311300, China 
  Corresponding author:  Zhang, J. (zhang8811@njfu.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  111-117
  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:  Chinese hickory (Carya cathayensis Sarg) is a unique tree species with seeds used for high-grade oil production. It is mainly distributed in northeastern China and is in high abundance on Tianmu Mountain, located at the junction of Zhejiang and Anhui provinces. Intensive management, including heavy application of chemical fertilizer and long-term application of herbicides, has resulted in serious soil loss and degradation. To evaluate the potential of sod-culture to improve soil fertility and microbial activities of Carya cathayensis forest land, we conducted a field intercropping experiment using four treatments: Chinese milk vetch (Astragalus sinicus L.), rape (Brassica campestris L.), ryegrass (Lolium perenne L.), and a no-tillage control. We compared the response of various components of total organic carbon (TOC) and microbial community functional diversity in each treatment. We found that interplanting rape, ryegrass, and Chinese milk vetch increased TOC contents by 23.12%, 26.61%, and 24.74% (P<0.05) compared with clean tillage, while there were no significant differences in TOC contents among the grass intercropping plots. After intercropping grasses for 4 years, the concentrations of microbial biomass carbon (MBC) in the plots of intercropping rape, ryegrass, and Chinese milk vetch were increased by 138.61%, 159.68%, and 144.24% respectively. The concentrations of water-soluble organic carbon (WSOC) in the plots of intercropping rape, ryegrass, and Chinese milk vetch were increased by 56.24%, 69.47%, and 66.05% respectively. There were no significant differences in MBC or WSOC concentrations among the intercropping treatments. The three interplantings increased soil carbonyl C by 29.9%-36.9% (P<0.05), and decreased alkyl C, O-alkyl C and aromatic C by 10.0%-16.4%, 18.9%-20.9%, and 10.5%-16.6%, as compared with clean tillage (P<0.05). However, there were no significant differences in the increase in soil carbonyl C and the decreases in alkyl C, O-alkyl C, and aromatic C among the treatments of intercropping grass. The ratios of aliphatic C/aromatic C, hydrophilic C/hydrophobic C, and aromaticity in soil under Chinese hickory were not affected by intercropping grasses. Interplanting grasses markedly improved microbial community functional diversity. The soil microbial activity (AWCD) values of the three intercropping treatments were much higher than the no-tillage treatment (P<0.05), while there were no significant differences in the soil AWCD values among intercropping grasses treatments. The microbial diversity indexes (H) and evenness index(E) in the treatments of rape and Chinese milk vetch were much greater than the treatment of no-tillage (P<0.05), but there was no significant difference between the ryegrass and no-tillage treatments. The results of this study demonstrated that sod cultivation is an effective soil management practice that improves soil quality and eliminates the detrimental effects of clean tillage in Chinese hickory production.
  Number of references:  33
  Main heading:  Soils 
  Controlled terms:  Agricultural machinery  -  Agronomy  -  Aromatic compounds  -  Aromatization  -  Biodegradation  -  Carbon  -  Cultivation  -  Fertilizers  -  Microbiology  -  Microorganisms  -  Organic carbon 
  Uncontrolled terms:  Chinese hickory (Carya cathayensis Sarg)  -  Interplanting  -  Microbial biomass carbon  -  Microbial functional diversities  -  Water-soluble organic carbon 
  Classification code:  821.3 Agricultural Methods -  821.1 Agricultural Machinery and Equipment -  804.1 Organic Compounds -  804 Chemical Products Generally -  802.2 Chemical Reactions -  801.2 Biochemistry -  483.1 Soils and Soil Mechanics -  461.9.2 Microbiology -  461.9 Biology
  DOI:  10.3969/j.issn.1002-6819.2013.20.016
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 16>

Accession number:  20134616980305
 
  Title:  Modeling and simulation of electronic control full hydraulic steering system for grain combine harvester
  Authors:  Zhang, Chengtao1, 2 Email author zhchtzct@sina.com; Tan, Yu1 Email author tanyu32@sina.com; Wu, Gang1; Wang, Shumao1 
  Author affiliation:  1 College of Engineering, China Agricultural University, Beijing 100083, China 
   2 School of Automobile and Traffic, Guangxi University of Science and Technology, Liuzhou 545006, China 
  Corresponding author:  Tan, Y. (tanyu32@sina.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  11-17
  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 recent years, combine harvester navigation system based on machine vision had important significance in improving the harvesting efficiency of combine harvester, reducing the labor intensity of the driver and so on. In order to realize the automatic steering control of the combine operation path, it is necessary to reconstruct the original hydraulic steering system of combine harvester. To analyze the steering performance of the modified electronically controlled hydraulic steering system for combine harvester in visual navigation system, mathematical models of the electronically controlled hydraulic steering system were established after introducing the structure of combine harvester visual navigation system. The system was mainly composed of combine harvester body, full hydraulic steering, steering transmission mechanism and hybrid stepping motor. In this paper, the mathematical models of the parts were established respectively. The steering model of combine harvester was firstly simplified to linear 2-DOF rear wheel steering vehicle model, and the basic handling dynamics model of combine harvester was established. Then, the dynamic mathematical model of simplified hydraulic steering system was given in the analysis of the fully hydraulic steering work principle for combine harvester. And then, the static model of the steering transmission mechanism was established according to its geometrical structures. Finally, the stepping motor model was simplified as an inertial system according to the step response performance, and its transfer function was given. The electronically controlled hydraulic steering system was simulated through the joint simulation method of each mathematical model by Simulink software. In order to verify the correctness of simulation models, the dynamic response characteristics of steering system was tested with the steering wheel angle step input of 90° on Xinjiang 2A combine harvester. In the real vehicle test, vehicle yaw rate was obtained by the vertical gyroscope, the lateral velocity signal was calculated according to the lateral acceleration of vehicle and the steering wheel angle signal by comprehensive estimation method. The comparative analysis of the simulation and real vehicle test showed that: Combine lateral velocity and yaw rate of the steady-state value was consistent with the real vehicle tests, and the output of lateral velocity was about -0.25 m/s, the output of yaw rate was about -12.5°/s, and the steady-state error is less than 5%. In the signal transient response, the transition time of simulation and real vehicle test were the same, which was about 1.8 s. The lateral velocity and yaw angle response speed of simulation was faster than the real vehicle test results, but the overall trend was the same. Therefore, the conclusion can be drawn that the established system models are accurate and reliable; And its consider not only the static mechanical characteristics of the electronically controlled hydraulic steering system, but also the rear wheel steering handling dynamics characteristics of combine harvester, full hydraulic steering dynamic characteristics and dynamic response performance of the stepping motor. The results reflect the dynamic and static characteristics of the electronically controlled hydraulic steering system for combine harvester visual navigation system, and provide a theoretical basis for the controller design of combine harvester visual navigation system and the realization of visual navigation system.
  Number of references:  25
  Main heading:  Automobile steering equipment 
  Controlled terms:  Computer simulation  -  Computer vision  -  Control  -  Dynamic response  -  Harvesters  -  Hydraulic machinery  -  Mathematical models  -  Models  -  Navigation  -  Navigation systems  -  Steering  -  Stepping motors  -  Velocity  -  Wheels 
  Uncontrolled terms:  Automatic steering control  -  Combine harvesters  -  Dynamic mathematical model  -  Dynamic response characteristics  -  Hybrid stepping motors  -  Mechanical characteristics  -  Transmission mechanisms  -  Visual navigation systems 
  Classification code:  931.1 Mechanics -  723.5 Computer Applications -  731 Automatic Control Principles and Applications -  732 Control Devices -  821.1 Agricultural Machinery and Equipment -  902.1 Engineering Graphics -  921 Mathematics -  716.3 Radio Systems and Equipment -  663.2 Heavy Duty Motor Vehicle Components -  632.2 Hydraulic Equipment and Machinery -  601.2 Machine Components -  434.4 Waterway Navigation -  408.1 Structural Design, General -  705.3 Electric Motors
  DOI:  10.3969/j.issn.1002-6819.2013.20.002
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 17>

Accession number:  20134616980334
 
  Title:  Comparative analysis on influencing factors of cultivated land use intensity in valley and middle mountain area of upper Dadu River watershed
  Authors:  Hua, Xiaobo1 Email author bensonhua@126.com; Yan, Jianzhong1 Email author yanjzswu@126.com; Wang, Qi1; Zhang, Yesheng1 
  Author affiliation:  1 College of Resources and Environment, Southwest University, Chongqing 400716, China 
  Corresponding author:  Yan, J. (yanjzswu@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  234-244
  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:  Changes in land use intensity are core academic issues in land-use change research. At present, empirical studies on features and driving forces on cultivated land use intensity in Western China are scarce. Besides, how to apply quantitative analysis methods to analyze the influencing factors on the cultivated land use intensity in depth also lack in the research. This paper analyzes differences of cultivated land use intensity based on the field surveys of 357 households in five villages from valley to the middle mountain area of Jinchuan County in the upper Dadu River watershed, by adopting the methods of participatory rural appraisal (PRA). This paper also qualitatively and quantitatively analyzes the factors influencing on the differences using Tobit model and Ordinary Least Squares (OLS) estimation method. The results show that: 1) There are statistically significant differences in cultivated land use intensity between the valley and the middle mountain area. Both capital intensity and labor intensity in valley are higher than that in middle mountain area. In capital intensity of land use, the inputs of seeds, fertilizer, pesticide, herbicide and other production in valley area are more than that in semi-mountain area. However, it shows the converse situation in mulch inputs. Labor intensity varies by different cropping system. From these three most important food crops cultivation in corn, wheat and potatoes, planting "Corn Wheat" two crops in a year are common in valley area, while in semi-mountain area, there has a gradual transition from originally planting two crops a year of corn and wheat to one crop of corn merely. 2) By quantitative analysis of Tobit and OLS regression model, we obtain that influencing factors on differences of cultivated land use intensity including originally contracted arable land, real per capita arable area, the family of fixed assets, the distance away from the market, income from the secondary and tertiary industries, the total family labor force, agricultural labor force, the number of years au pair and social relations. In valley area, originally contracted arable land and income from the secondary and tertiary industries have the negative impact on cultivated land use intensity, while real per capita arable area, the family of fixed assets, the total family labor force, agricultural labor force and the number of year au pair have positive influence. In semi-mountain area, originally contracted arable land and the total family labor force have the positive impact on cultivated land use intensity. However, the family of fixed assets, the distance away from the market and social relations have the negative impact. 3) Cultivated land resource endowment and number of agricultural labor force are key factors to cause cultivated land use intensity differences. In addition, the conditions or environment for agricultural production and family income levels also have important impacts on cultivated land use intensity differences. Using the results as bases, this study proposes that the government should promote the land transfer orderly, support the agricultural labor force, such as increasing agricultural subsidies on labor-saving input, improving labors' education and health levels, and further improving the rural infrastructure to facilitate the local farmers, etc.
  Number of references:  39
  Main heading:  Land use 
  Controlled terms:  Agriculture  -  Commerce  -  Crops  -  Cultivation  -  Economics  -  Landforms  -  Least squares approximations  -  Regression analysis  -  Rivers  -  Rural areas  -  Watersheds 
  Uncontrolled terms:  Agricultural productions  -  Comparative analysis  -  Cultivated lands  -  Dadu rivers  -  Influencing factors  -  Ordinary least squares  -  Participatory rural appraisals  -  Statistically significant difference 
  Classification code:  922.2 Mathematical Statistics -  921.6 Numerical Methods -  911.2 Industrial Economics -  971 Social Sciences -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  444.1 Surface Water -  403 Urban and Regional Planning and Development -  481.1 Geology
  DOI:  10.3969/j.issn.1002-6819.2013.20.031
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 18>

Accession number:  20134616980326
 
  Title:  Effect of ecological interception system in reducing non-point source pollution from vegetable fields
  Authors:  Shan, Li'nan1, 2 Email author shanlinan_1986@zju.edu.cn; Ding, Nengfei3; Wang, Hongcai1; Lian, Xu1; Liu, Yili1; He, Yunfeng1, 2 Email author yfhe@zju.edu.cn 
  Author affiliation:  1 College of Environmental and Resource Science, Zhejiang University, Hangzhou 310058, China 
   2 Key Laboratory of Non-Point Source Pollution Control, Ministry of Agriculture, Hangzhou 310058, China 
   3 Zhejiang Academic of Agricultural Sciences, Hangzhou 310021, China 
  Corresponding author:  He, Y. (yfhe@zju.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  168-178
  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 ever-worsening problem of non-point source pollution has plagued vegetable industries worldwide. This study attempts to tackle this problem using an ecological interception system in Taihu basin, Zhejiang province, to examine the effects of removal of nitrogen (N) and phosphorous (P) from the effluents of vegetable fields. The system consisted of ecological ditches with filtration apparatus optimized for location, efficiency, and cost control. Construction of the system started in September 2010 and was completed and put into operation in April 2011. The results showed total-N removal rates of 79.75% and 88.86% in July 2011 and July 2012 respectively, which were 2.47 and 3.02 times the controls for the same years. The total-P removals in July 2011 and July 2012 were 86.74% and 96.35% respectively, which were 2.39 and 2.84 times of the controls for the same years. Compared to 2010, the total-N and total-P concentrations in the effluents in 2011 and 2012 were significantly reduced with total-N concentrations at 2.23-5.91 and 1.51-4.62 mg/L respectively and total-P concentrations 0.33-1.39 and 0.14-0.97 mg/L, respectively. The overall removals of nitrogen in 2011 and 2012 were 33%-52% and 43%-67% respectively and phosphorous 23%-59% and 43%-82% respectively. The removals were the highest during the rainy season June through September and higher in 2012 than in 2011. Not only did the project fully improve absorption and interception of nitrogen and phosphorus and other nutrients from vegetable waste water, it also extended the hydraulic retention time, reduced the emission load of vegetable waste water, and increased cycle utilization rate of vegetable wastewater. As a proof of concept, the project was a huge success, showing promising results not only for wastewater treatment but also landscape beautification and economic benefits for the region. There is no denying the important practical significance of exploring environmentally friendly high-efficiency systems for ecological agricultural uses.
  Number of references:  24
  Main heading:  Vegetables 
  Controlled terms:  Ecology  -  Effluents  -  Engineering  -  Nitrogen  -  Nitrogen removal  -  Phosphorus  -  Pollution  -  Wastewater treatment 
  Uncontrolled terms:  Economic benefits  -  Hydraulic retention time  -  Nitrogen and phosphorus  -  Non-point source pollution  -  Utilization rates  -  Vegetable Field  -  Vegetable industry  -  Zhejiang Province 
  Classification code:  821.4 Agricultural Products -  804 Chemical Products Generally -  802.2 Chemical Reactions -  901 Engineering Profession -  454.3 Ecology and Ecosystems -  452.4 Industrial Wastes Treatment and Disposal -  452.3 Industrial Wastes -  454.2 Environmental Impact and Protection
  DOI:  10.3969/j.issn.1002-6819.2013.20.023
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 19>

Accession number:  20134616980308
 
  Title:  Research on matching recognition method of oscillating fruit for harvesting robot
  Authors:  Lü, Jidong1 Email author vveaglevv@163.com; Zhao, De'an2 Email author dazhao@ujs.edu.cn; Ji, Wei2 
  Author affiliation:  1 School of Information Science and Engineering, Changzhou University, Changzhou 213164, China 
   2 School of Electrical and Information Engineering, Jiangsu University, Zhenjiang 212013, China 
  Corresponding author:  Zhao, D. (dazhao@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  32-39
  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:  When the harvesting robot picks fruits, the separation of fruit and fruit branch leads to the other fruits oscillating on the fruit tree, using the cut way or twist way. In addition, the wind also leads to the fruit oscillating. In the past, the harvesting robot using the static recognition method recognized them accurately when the oscillating fruits would stop and either wait or frequently recognize them in the process of the fruits' oscillation, which spent more picking time and influenced the total picking efficiency of the harvesting robot. Because the static recognition method cannot obtain the dynamic characteristics of the oscillating fruit, the harvesting robot cannot accurately pick them during the fruits' oscillation. It is obvious that the static recognition method cannot meet the fast picking requirement of the oscillating fruits. In order to resolve the problem that the fruit oscillation influences on its recognition, orientation, and then fast picking, the dynamic recognition method under the fruit oscillation condition for the harvesting robot was researched. In the first place, the dynamic recognition process of oscillating fruit was introduced. The picking target fruit was determined which would be taken as the template of the following recognition. In the next place, the Fast Inverse Square Root algorithm and Fast Hartley Transform algorithm were applied to increase the recognition speed of the Mean-residual Normalized Product Correlation matching algorithm. Then, the fast Mean-residual Normalized Product Correlation matching algorithm was improved to be the property of resistance to rotation again, which was used to recognize the dynamic images. At last, the matching recognition tests were done, and the test results showed that the average recognition time of the improved fast algorithm was 0.33 s and the improved rotation invariant algorithm had the rotation invariance in the wide range of [-55°, 60°] and could recognize the oscillatory fruit accurately. In addition, the timely update of the template was also used, which could meet the recognition requirement.
  Number of references:  26
  Main heading:  Fruits 
  Controlled terms:  Algorithms  -  Harvesting  -  Image matching  -  Image recognition  -  Orchards  -  Robots  -  Template matching 
  Uncontrolled terms:  Correlation matching  -  Dynamic characteristics  -  Fast hartley transforms  -  Matching recognition  -  Oscillation  -  Recognition methods  -  Rotation invariance  -  Square-root algorithms 
  Classification code:  716 Telecommunication; Radar, Radio and Television -  723 Computer Software, Data Handling and Applications -  731.5 Robotics -  741 Light, Optics and Optical Devices -  821.3 Agricultural Methods -  821.4 Agricultural Products
  DOI:  10.3969/j.issn.1002-6819.2013.20.005
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 20>

Accession number:  20134616980323
 
  Title:  Intelligent service system of pollution-free agricultural products catalog based on personalized features
  Authors:  Xi, Lei1, 2 Email author hnaustu@126.com; Zheng, Guang1, 2; Wang, Qiang1, 2; Pang, Xiaodan1, 2; Ding, Baohua3; Ma, Xinming1, 2, 4 Email author xinmingma@126.com 
  Author affiliation:  1 College of Information and Management Science, Henan Agricultural University, Zhengzhou 450002, China 
   2 HHH Science Observation and Experiment Station of Agricultural Information and Technology, Ministry of Agriculture, Zhengzhou 450002, China 
   3 Agriculture Product Quality Safety Center, Ministry of Agriculture, Beijing 100028, China 
   4 Agronomy College, Henan Agricultural University, Zhengzhou 450002, China 
  Corresponding author:  Ma, X. (xinmingma@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  142-150
  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:  For promoting pollution-free agricultural products' circulation and improving the service quality of the certified product information, to realize the personalized information retrieval and recommendation of the certified product information, this paper carried out key technology research of the pollution-free agricultural products catalog intelligence services. Employing the product concept, properties, and semantic relations as the principal part, the ontology model of a product catalogue was designed. Moreover, the product directory domain ontology was also set up to form the pollution-free agricultural product electronic catalog. Based on the products catalogue domain ontology, the users' preference feature model was conducted from the ontology concept level. The personalized product catalog weighted ontology model was established based on the concept of weights set by the comprehensive value of the semantic resolution and users' degree of interest. Furthermore, the personalized product catalog weighted ontology establishment algorithm was also designed to realize the dynamic, accurate, and comprehensive description of user interests. Through individual filtering, comprehensive filtering, concept mapping, semantic query expansion, and query result optimization, the recommendation and retrieval algorithm of the personalized product catalog information was constructed to establish the product catalog intelligence service system. In the contrasting experiment of the search results, compared with three used retrieval modes of the retrieval based on domain ontology, the optimized retrieval based on semantic similarity, and the optimized retrieval based on personalized ontology, the degree of the users' satisfaction increased by 31%, 21%, and 14% respectively. The experiment's result showed that the catalog intelligence service system could improve the quality and satisfaction of the pollution-free agricultural products directory information retrieval and recommendation to a certain extent, and met the personalized requirements. Meanwhile, the system also provided the technical support for the promotion, the brand sales, and electronic trading of the pollution-free agricultural product and showed a good prospect for application.
  Number of references:  28
  Main heading:  Search engines 
  Controlled terms:  Agricultural products  -  Algorithms  -  Experiments  -  Information filtering  -  Information retrieval  -  Information services  -  Ontology  -  Optimization  -  Pollution  -  Query processing  -  Semantics 
  Uncontrolled terms:  Intelligence services  -  Intelligent service systems  -  Intelligent Services  -  Personalizations  -  Personalized information retrieval  -  Pollution-Free Agricultural Products  -  Product catalogs  -  Semantic query expansion 
  Classification code:  921.5 Optimization Techniques -  903 Information Science -  901.3 Engineering Research -  821.4 Agricultural Products -  723.5 Computer Applications -  723 Computer Software, Data Handling and Applications -  454.2 Environmental Impact and Protection
  DOI:  10.3969/j.issn.1002-6819.2013.20.020
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 21>

Accession number:  20134616980307
 
  Title:  Design and experiment on rolling and crushing combined extracting machine for banana stem fiber
  Authors:  Zhang, Xirui1 Email author zhangxirui_999@sina.com; Zheng, Kan1; Liang, Dong1; Zhang, Jin2 Email author zj1204@tom.com; Xue, Zhong2 
  Author affiliation:  1 School of Mechanics and Electrics Engineering, Hainan University, Haikou 570228, China 
   2 Agricultural Machinery Institute of Chinese Academy of Tropical Agricultural Sciences, Zhanjiang 524091, China 
  Corresponding author:  Zhang, J. (zj1204@tom.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  24-31
  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:  Banana stalk is the main byproduct of bananas after post-harvest, and is mainly decayed naturally or discarded in the field, due to large stalk, high moisture content and other characteristics, resulting in a great waste of resources and an environmental pollution problem. Meanwhile, banana stalk contains high-quality plant fiber, which is lightweight, with strong permeability, also has high economic value, which is suitable for the production of medium and top-grade products, such as suits, shirts, ties, and various decorations, as well as fine paper. So far, the domestic and foreign research on fiber extraction and application mostly concentrates in rice straw, corn stalk, cotton stalk, biogases, or pineapple leaf, etc. Drawing on the previous studies, water immersion method, biochemical and mechanical extraction method and other methods are available, but just the immersion method and the biochemical method are mainly adopted by researchers. Domestic mechanical extraction of banana stalk fiber is still in its infancy, due to its regional characteristics, particularly for fiber extraction machinery, which is rarely reported both at home and abroad. Based on the above issues, a banana fiber extracting machine with a hybrid of rolling and smashing was put forward and designed in this paper, which was mainly composed of a conveying device, rolling device, rolling device II, smashing device, machine cover, walking wheel, drainage pipe, motor, and machine chassis. During the working period, banana stalk was conveyed to a rolling device I via conveyor belt, and crushed first through the relative rotation of the upper roller and lower roller (distance between two rollers of 5-10 cm). Then, it was conveyed to rolling device II, and was crushed secondly through the relative rotation of the upper roller and lower roller (distance between two rollers of 2-5 cm). After the above two steps, more than 80% of water was extruded, and was discharged through the drainage device. Then, the crushed banana stalk was smashed by high-speed knives in the smashing device. Finally, the processed banana fiber was discharged through the lower bezel. Referring to the current situation, the paper designed the rolling and crushing combined type extracting machine for banana stem fiber. It gave the main structure of some components including drive system, rolling device I, rolling deviceII, crushing device and motor, and simulated the crushing knife by finite element analysis. The sample test results showed as below: the passing rate of fiber rubbing objects was 89.2%, the impurity rate was 8.6%, the output was 206 kg/h, and the energy consumption was 20.2 kW·h/100kg. The research indicates that the design meets the requirements. Compared with the half feeding type extracting machine for banana stem fiber, the rolling and crushing combined type extracting machine for banana stem fiber improved the passing rate of fiber rubbing objects by 8.1%, decreased the impurity rate by 6.5%, improved the output by 71.7%, and decreased the energy consumption by 10.6%. Successful implementation of this project will lay a solid theoretical design of high performance to adapt to the field of banana stalk fiber extraction machines, and will have important practical significance to promote the sustainable development of the tropical agricultural areas in China.
  Number of references:  29
  Main heading:  Fruits 
  Controlled terms:  Agricultural machinery  -  Belt conveyors  -  Biomass  -  Crushing  -  Design  -  Energy utilization  -  Experiments  -  Extraction  -  Fibers  -  Mechanical permeability  -  Rollers (machine components) 
  Uncontrolled terms:  Banana stalk  -  Biochemical methods  -  Environmental pollution problem  -  High moisture contents  -  Mechanical extraction  -  Regional characteristics  -  Waste of resources  -  Water immersion method 
  Classification code:  931.2 Physical Properties of Gases, Liquids and Solids -  901.3 Engineering Research -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  817 Plastics and Other Polymers: Products and Applications -  812 Ceramics, Refractories and Glass -  802.3 Chemical Operations -  692.1 Conveyors -  601.2 Machine Components -  525.3 Energy Utilization -  525.1 Energy Resources and Renewable Energy Issues -  408 Structural Design
  DOI:  10.3969/j.issn.1002-6819.2013.20.004
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 22>

Accession number:  20134616980333
 
  Title:  Analysis on spatial difference of newly increased farmland by land consolidation in China at county level
  Authors:  Guan, Xu1 Email author njnugx826@163.com; Jin, Xiaobin1 Email author jinxb@nju.edu.cn; Pan, Qian1; Zhou, Yinkang1 
  Author affiliation:  1 School of Geographic and Oceanographic Science, Nanjing University, Nanjing 210023, China 
  Corresponding author:  Jin, X. (jinxb@nju.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  226-233
  Language:  Chinese
  ISSN:  10026819 
  CODEN:  NGOXEO 
  Document type:  Journal article (JA)
  Publisher:  Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
  Abstract:  In order to find out the spatial difference regarding quantity and source structure of newly increased cultivated land by consolidation in China, the data are acquired from a consolidation project from 2006 to 2012 by the Ministry of Land and Resources. This paper first analyzes the spatial-temporal pattern of China's newly increased cultivated land at county level according to corresponding data, and Geoda software is used to analyze the spatial correlation of newly increased cultivated land area and produces a LISA cluster map. Then the source structure of newly increased cultivated land is divided into seven categories, which forms a spatial-temporal pattern map. Finally we analyze the spatial difference of quantity and source structure of these land based on the above three maps, aiming to figure out the reason for these differences through analyzing natural conditions, economic development level, land use policy and other factors. The results showed that: 1) In terms of spatial distribution, newly increased cultivated land in eastern China ranks higher than that of the western, developed areas higher than less developed places, grain producing areas higher than the counterparts, and plains higher than mountainous and hilly areas. It can be easily found that the amount of newly increased cultivated land is closely related to regional economy and the reserve of cultivated land. 2) Newly increased cultivated land at county level has a clear positive correlation with spatial allocation, namely, developed regions near the eastern coast and key areas of land development are high-high areas, whereas less developed areas in central and western China, where was poor concerning natural condition and regional resources reserve are low-low areas. At the same time, high-low areas and low-high areas form great contrasts with surrounding areas in economy and resource. 3) When it comes to the source structure of newly increased cultivated land, there are significant regional and provincial differences. Newly increased cultivated land in the eastern coastal developed regions comes mainly from land consolidation and reclamation while in northern regions development and consolidation contribute the most. Source structure in central China was complex. To be more specific, most of the cultivated land in Sichuan and Chongqing are from land consolidation, while in middle Shanxi and Hubei land consolidation and reclamation create more cultivated land. Land development rate is high in Guangdong, Guangxi, Hunan, etc. Even between those provinces that are similar in economy and resource, such as Guangdong and Zhejiang, Liaoning and Jilin, significant differences still exist. The above results reflect that the source structure of newly increased cultivated land in eastern coastal provinces is reasonable, and its current arrangement of land consolidation is suitable to optimize the structure of land use and sustainable development. Meanwhile, the source structure of newly increased cultivated land of some provinces is unsatisfied and needs to be guided and changed. In the future, the guiding role of national land consolidation planning should be strengthened to standardize the provincial land consolidation project. Taking the opportunity of the construction of well-facilitated primary farmland, it is necessary to give priority to land consolidation, attach importance to land reclamation and control land development.
  Number of references:  32
  Main heading:  Land use 
  Controlled terms:  Consolidation  -  Economics  -  Farms  -  Land reclamation  -  Regional planning  -  Rural areas  -  Spatial variables measurement 
  Uncontrolled terms:  Consolidation projects  -  County  -  Cultivated lands  -  Economic development  -  Land consolidation planning  -  Positive correlations  -  Spatial correlations  -  Spatial differences 
  Classification code:  403.2 Regional Planning and Development -  442.2 Land Reclamation -  483 Soil Mechanics and Foundations -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  943.2 Mechanical Variables Measurements -  971 Social Sciences
  DOI:  10.3969/j.issn.1002-6819.2013.20.030
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 23>

Accession number:  20134616980310
 
  Title:  Variable universe fuzzy control based on inverse-model decoupling for wind water pumping
  Authors:  Li, Lin1 Email author 285570227@qq.com; Zhou, Guoxiong1 Email author 51840157@qq.com 
  Author affiliation:  1 School of Computer and Information Engineering, Central South University of Forestry, Changsha 410000, China 
  Corresponding author:  Zhou, G. (51840157@qq.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  46-53
  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 recent years, with the development of new energy technology, a hybrid water system of wind power and conventional energy supplement was rapidly developed in China. However, wind resources are affected by seasonal and geographical patterns, water system, wind energy, and conventional energy cooperation. The two are mutual coupling, so the control effect is difficult to guarantee. Therefore studies of one kind of establishment of auxiliary control system based on dynamic decoupling in the wind, the stability, water effect, and promotion of wind water pumping technology to solve the power shortage in agricultural and pastoral areas, have important practical significance for improving the ecological environment in China. The traditional decoupling algorithm with a feed-forward compensation method based on expert rules and the state equation decoupling method based on requirements, moths model of controlled object were described, because the wind is certain nonlinear water system, and mathematical models are difficult to access, so these methods are difficult to use. An intelligent decoupling method based on an inverse model does not need to rely on the mathematical model, or the nonlinear control system in the field, and achieved good results. Based on the in-depth analysis of the water system on the wind, the wind water pumping system, physical and chemical complex, the wind, the auxiliary power coupling problem, the paper put forward a fuzzy control method based on a neural network inverse decoupling variable. By using the neural network method to identify the inverse system of the original system, and being connected in series with the original system, a pseudo linear system, the wind, the auxiliary power is decoupling. At the same time, the fuzzy controller to control the wind, auxiliary power independently, using the variable universe theory to improve the fuzzy control theory domain, enhance the system's ability to adapt to the environment. The control system consisted of the inverse system decoupling compensation based on a neural network, and based on the variable universe fuzzy algorithm in wind, and the auxiliary power independent control of the two parts. A neural network decoupling compensator, utilizing the self-learning characteristic of the neural network, the reverse identification of the original system, thus approaching wind inverse model of water system, the parallel inverse system with the original system, a pseudo linear system, so that the wind power transmission and auxiliary power transmission and conversion into subsystems are independent of each other, then a linear system control method was used to control the variable universe fuzzy algorithm based on a fuzzy controller. First, according to the wind, the auxiliary power was set the detection feedback value and system, the wind, the auxiliary power closed the loop control; and then the variable universe fuzzy algorithm was used to solve the parameter sensor parameter drift and system device of fixed rules of fuzzy algorithm, the algorithm is adaptation to environment improvement. In order to verify the feasibility of this method, the inverse modeling method of a model simulation test; at the same time, in order to validate the proposed algorithm, the test of comparison, carried on the analysis to the control system from the point of system performance. The inverse model in the simulation experiment of variable pump and diesel engine control showed average errors of 6.3% and 4.5%, and a centrifugal pump speed error in the actual operation of the control within 5%, proved the effectiveness of this method. This fully illustrated the influence of the method in this paper that can effectively restrain the velocity changes, and has extremely vital significance to the promotion of the water system of the wind.
  Number of references:  31
  Main heading:  Inverse problems 
  Controlled terms:  Algorithms  -  Computer simulation  -  Control systems  -  Diesel engines  -  Equations of state  -  Fuzzy control  -  Fuzzy sets  -  Linear systems  -  Mathematical models  -  Neural networks  -  Nonlinear equations  -  Power transmission  -  Pumps  -  Waterworks  -  Wind power 
  Uncontrolled terms:  Decoupling compensators  -  Ecological environments  -  Feed-forward compensation  -  Inverse mode  -  Inverse modeling methods  -  New energy technologies  -  Variable regions  -  Variable universe fuzzy controls 
  Classification code:  921 Mathematics -  731.1 Control Systems -  723.5 Computer Applications -  723.4 Artificial Intelligence -  921.1 Algebra -  618.2 Pumps -  612.2 Diesel Engines -  602.2 Mechanical Transmissions -  446 Waterworks -  615.8 Wind Power (Before 1993, use code 611 )
  DOI:  10.3969/j.issn.1002-6819.2013.20.007
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 24>

Accession number:  20134616980316
 
  Title:  Analysis on hydraulic performance of bidirectional flow channel of drip irrigation emitter
  Authors:  Tian, Jiyang1 Email author tjyshd@126.com; Bai, Dan1 Email author baidan@xaut.edu.cn; Ren, Changjiang1; Wang, Xinduan1 
  Author affiliation:  1 Institute of Water Resources and Hydroelectric Engineering of Xi'an University of Technology, Xi'an 710048, China 
  Corresponding author:  Bai, D. (baidan@xaut.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  89-94
  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 bidirectional flow channel is a new kind of channel for drip irrigation emitter, it has the advantages of simple structure, easy manufacturing and good hydraulic performance. The main working principle of the bidirectional flow channel is mixing the forward flow and the backward flow to enhance the effect of energy dissipation. The forward flow and backward flow are produced by splayed wall and V-shape wall in the channel. In order to study the effects of structural parameters on hydraulic performances, choosing 9 key factors from the structural parameters and arranging 12 experimental schemes to study flow index and flow coefficient. The experiments can obtain the inlet pressure of channel and the outlet flow rate. Each experimental scheme was set 3 repeats to make sure that the results are accurate. Based on the flux of bidirectional flow channel under different pressures, the flow index and flow coefficient can be obtained by using linear regression, and then regression equations can be built. The regression equations regressed by the multivariable regression method about flow index and flow coefficient to 9 structural parameters have the higher relativity, the correlation coefficients are 0.999 and 0.998. The regression equations are verified by another experimental scheme which number is 13. The results showed that the regression equations are reliable and accurate. The flow index of bidirectional flow channel is in the range from 0.40 to 0.47, whose hydraulic performance is good. According to the t-test analysis, all of the 9 structural parameters are the important factors to the flow index at the 0.05 significance level, in which α, the field angle of V-shape wall is the most important factor, and followed by c, the distance between the vertex of V-shape wall and the medial of the side wall at the outlet; d1, the distance between the both sides of V-shape wall and the side wall of channel; β, the field angle of splayed wall; b, the width of inlet; d4, the distance between the vertex of V-shape wall and the vertex of splayed wall; d3, the width of the middle orifice of splayed wall; a, the width of outlet; d2, the distance between the both sides of splayed wall and the side wall of channel. There is a negative correlation between d1, a, b, β, c and flow index, while there is a positive correlation between other four factors and flow index; the outlet width and the field angle of splayed are the important factors to the flow coefficient, while the outlet width is the most important factor, there is a positive correlation between these two factors and flow coefficient. These conclusions can provide an evidence for designing bidirectional flow channel and make the hydraulic performance of the new channel better.
  Number of references:  25
  Main heading:  Wall flow 
  Controlled terms:  Channel flow  -  Energy dissipation  -  Inlet flow  -  Irrigation  -  Regression analysis  -  Walls (structural partitions) 
  Uncontrolled terms:  Bi-directional flows  -  Correlation coefficient  -  Emitter  -  Hydraulic performance  -  Multivariable regression  -  Negative correlation  -  Positive correlations  -  Structural parameter 
  Classification code:  402 Buildings and Towers -  525.4 Energy Losses (industrial and residential) -  631.1 Fluid Flow, General -  821.3 Agricultural Methods -  922.2 Mathematical Statistics
  DOI:  10.3969/j.issn.1002-6819.2013.20.013
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 25>

Accession number:  20134616980317
 
  Title:  Evaluation on irrigation efficiency of irrigation district in arid region based on evapotranspiration estimated from remote sensing data
  Authors:  Jiang, Lei1 Email author lei-jiang11@mails.tsinghua.edu.cn; Yang, Yuting1; Shang, Songhao1 Email author shangsh@tsinghua.edu.cn 
  Author affiliation:  1 State Key Laboratory of Hydroscience and Engineering, Tsinghua University, Beijing 100084, China 
  Corresponding author:  Shang, S. (shangsh@tsinghua.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  95-101
  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 evaluate the irrigation efficiency of irrigation districts in arid regions where crop growth relies heavily on irrigation, a new evaluation indicator, coefficient of irrigation water effective utilization, was proposed. The difference of evapotranspiration and precipitation in irrigated land during the crop growing season was considered as the effective use of irrigation water, and the ratio of effective use of irrigation water and net water diversion to the irrigation district was defined as the coefficient of irrigation water effective utilization (ηe). With the development of a remote sensing evapotranspiration technique in recent decades, spatial and temporal variations of evapotranspiration can be estimated with acceptable precision. Then ηe can easily be estimated from evapotranspiration and measured precipitation and net water diversion, which can avoid the difficulties of accurate measurement or simulation of irrigation water stored in the crop root zone in a traditional irrigation water use efficiency evaluation. A case study in the Hetao irrigation district in North China was carried out to estimate the coefficient of irrigation water effective utilization throughout the period 2000-2010 based on remote sensing evapotranspiration data calculated by the SEBAL (Surface Energy Balance Algorithm for Land) model, meteorological data, and water diversion data. Results indicated that ηe tends to increase with the implementation of water-saving irrigation projects. ηe varied from 0.547 to 0.715 during 2000-2010 and ηe decreased with precipitation and net water diversion. The correlation coefficients between ηe and precipitation, and ηe and net water diversion were -0.32 and -0.57, respectively. Moreover, ηe was estimated under different precipitation and water diversion schemes after water-saving irrigation projects. Results indicated that the reduction of water diversion had a greater effect than the water-saving irrigation projects on ηe. However, water consumption in irrigated land kept at a relatively stable level although water diversion tended to decrease in recent years, which showed the good performance of water-saving irrigation projects.
  Number of references:  30
  Main heading:  Water supply 
  Controlled terms:  Arid regions  -  Evapotranspiration  -  Flood control  -  Irrigation  -  Meteorology  -  Remote sensing 
  Uncontrolled terms:  Correlation coefficient  -  Hetao irrigation districts  -  Irrigation districts  -  Irrigation efficiency  -  Irrigation waters  -  Spatial and temporal variation  -  Surface energy balance algorithm for lands  -  Water-saving irrigation 
  Classification code:  443 Meteorology -  444.1 Surface Water -  446.1 Water Supply Systems -  454.1 Environmental Engineering, General -  731.1 Control Systems -  821.3 Agricultural Methods
  DOI:  10.3969/j.issn.1002-6819.2013.20.014
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 26>

Accession number:  20134616980320
 
  Title:  Estimating crop coefficients of winter wheat based on canopy spectral vegetation indices
  Authors:  Li, Heli1, 2, 3 Email author lhl237666@126.com; Luo, Yi2 Email author luoyi.cas@hotmail.com; Zhao, Chunjiang1; Yang, Guijun1 
  Author affiliation:  1 Beijing Research Center for Information Technology in Agriculture, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China 
   2 Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences, Beijing 100101, China 
   3 State Key Laboratory of Remote Sensing Science, Institute of Remote Sensing and Digital Earth, Chinese Academy of Sciences, Beijing 100101, China 
  Corresponding author:  Luo, Y. (luoyi.cas@hotmail.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  118-127
  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:  At present, many studies have been carried out on crop coefficients and its variation over years under local climate conditions, but little attention has been given to its estimation method for a regional scale, which plays a key role in the regional application of the FAO 56 crop coefficient approach in crop evapotranspiration and transpiration estimation. In this work, experiments including five nitrogen (N) treatments were conducted in the 2008-2009 and 2009-2010 seasons to investigate the relationships between the crop coefficient (Kc), basal crop coefficient (Kcb) and eight common canopy vegetation indices (VIs) of winter wheat, as well as the effects of N and water stress on them. In addition, the feasibility and the performances of VIs on Kc and Kcb estimation of winter wheat were analyzed. Results demonstrated that high levels of N were associated with high Kcb and low Ke, and vice versa, which resulted in no obvious regular differences in Kc among different N treatments. Crop Kc was weakly correlated with VIs (the coefficient of determination R2=0.094~0.150, p<0.01, n=195) due to the variations in soil evaporation and soil background, while Kcb had strong correlations with VIs (R2=0.511~0.685, p<0.01, n=195). In addition, the water stress before resulting in an obvious sign on crop canopy spectral characteristics can introduce considerable scatter in the relations between Kcb and VIs, while N stress had no effects on them. Validation results showed that VIs performed well in crop Kcb estimation, and the enhanced vegetation index (EVI) gave the best accuracy (R2=0.765~0.864, n=150). The proposed method would be more favorable for regional application, since VIs can be easily collected by means of remote sensing. However, it should be pointed out that the method may have some limitations under the conditions with water stress but is not severe according to the above analysis, and as in this case, additional water stress information collected from other sources like thermal images and ground-based wireless sensor network observation would be needed.
  Number of references:  34
  Main heading:  Crops 
  Controlled terms:  Estimation  -  Experiments  -  Nitrogen  -  Vegetation  -  Water supply  -  Wireless sensor networks 
  Uncontrolled terms:  Basal crop coefficients  -  Coefficient of determination  -  Crop coefficient  -  Enhanced vegetation index  -  Spectral characteristics  -  Spectral vegetation indices  -  Vegetation index  -  Winter wheat 
  Classification code:  921 Mathematics -  901.3 Engineering Research -  821.4 Agricultural Products -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  804 Chemical Products Generally -  732 Control Devices -  446.1 Water Supply Systems
  DOI:  10.3969/j.issn.1002-6819.2013.20.017
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 27>

Accession number:  20134616980311
 
  Title:  Calculation and validation of fluid pressure of balance cavity in centrifugal pump
  Authors:  Liu, Zailun1, 2 Email author liuzl88@sina.com; Dong, Wei1 Email author 735381559@qq.com; Zhang, Nan1; Wu, Jiao1 
  Author affiliation:  1 College of Energy and Power Engineering, Lanzhou University of Technology, Lanzhou 730050, China 
   2 Engineering Institute of Wenzhou Pump and Valve, Lanzhou University of Technology, Wenzhou 325105, China 
  Corresponding author:  Dong, W. (735381559@qq.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  54-59
  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 the design of a centrifugal pump, the double seal ring impeller with the balance hole is the main methods of balancing axial thrust. The cover force produced by the pressure difference in the balance cavity region was the main part of axial thrust. A study on the calculation method of fluid pressure of the balance cavity in the impeller has important significance for the accurate calculation of the axial thrust. In order to solve the fluid pressure calculation of the balance cavity in the impeller, the two dimensionless characteristic parameters about specific area kˉ and pressure coefficient pˉ were introduced. Under the condition of the fluid leakage in the balance hole and the back seal ring clearance at the impeller was equal, a calculation model of fluid pressure in the balance cavity was derived. The dimensionless curve of the calculation model was pˉ=f(kˉ), and an undetermined coefficient a and b in calculation method was introduced. For the 3BA-6 pump, under the condition of the different diameter of the balance hole, the theoretical dimensionless curves of the fluid pressure in the balance cavity at design point were obtained. To illustrate the problem, under the condition of the same pump structure, a verification experiment by taking the same diameter of balance hole as the calculation was conducted. The fluid pressure of the back seal ring outlet and impeller inlet at the design point was measured, so the experiment dimensionless curve was obtained. Research showed that, the experiment dimensionless curve and the theoretical dimensionless curve on the fluid pressure in the balance cavity at the design point were coincident, and the test curve above the theoretical curve, but when kˉ=0.5, pˉ was maximum between the experiment dimensionless curve and the theoretical dimensionless curve, the maximum absolute error was 0.049. The result proved that the calculation model of fluid pressure in the balance cavity was correct and feasible. For a centrifugal pump of double seal ring impeller with a balance hole, the specific expressions on the calculation model of fluid pressure in the balance cavity by calculating was obtained. Furthermore, the pressure difference of the two sides of the impeller back cover and the cover force produced by the pressure difference in balance cavity region can be calculated.
  Number of references:  26
  Main heading:  Seals 
  Controlled terms:  Calculations  -  Centrifugal pumps  -  Experiments  -  Impellers  -  Models 
  Uncontrolled terms:  Accurate calculations  -  Calculation models  -  Dimensionless curves  -  Fluid pressures  -  Maximum absolute error  -  Pressure coefficients  -  Pressure differences  -  Undetermined coefficients 
  Classification code:  902.1 Engineering Graphics -  901.3 Engineering Research -  723 Computer Software, Data Handling and Applications -  921 Mathematics -  721 Computer Circuits and Logic Elements -  618.2 Pumps -  601.2 Machine Components -  619.1.1 Pipe Accessories
  DOI:  10.3969/j.issn.1002-6819.2013.20.008
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 28>

Accession number:  20134616980329
 
  Title:  Finite element analysis on large deformation of compressed cornstalk powder
  Authors:  Tao, Siwei1 Email author tsw20031117@qq.com; Liu, Xianshuang1; Zhao, Dong1 Email author zhaodong68@bjfu.edu.cn 
  Author affiliation:  1 School of Technology, Beijing Forestry University, Beijing 100083, China 
  Corresponding author:  Zhao, D. (zhaodong68@bjfu.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  199-205
  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:  Molded tray that was manufactured by crop stalks is a new type of green packaging material. In order to provide a basic date for design and technology for molded tray, it is necessary to understand the forming laws of cornstalk powder in the course of molded compression. Since previous research to study the principle of compression and forming for cornstalk used rheology theory, it could not solve the problem of the plastic deformation in the compression process. In addition, the molding process of stalk powder is the problem of double nonlinear that contains material nonlinear behavior and geometric nonlinear behavior. To analyze the relationship between the deformation and load histories for cornstalk powder, the uni-axial compression tests of cornstalk powder, which was with about 12% of moisture and 0.4-1.0 mm of granularity, were studied in this paper. The elastoplastic characteristics of cornstalk powder in molded compression process were investigated. Then the relationships between load and displacement were discovered after analyzing the results of the experiments. Moreover, the constitutive equation of cornstalk powder was established using the non-linear fitting method. Using plasticity theory, the Eulerian method of large deformation for the compression analysis of powder was introduced. Based on finite deformation theory, this paper studied a finite element model of axial symmetry for cornstalk powder during compaction, and a FEM program was proposed. Three main formulae, including tangent modulus, tangent stiffness matrix, and unbalanced force, were discussed in the model of the large deformation. The deformation principles were revealed during the forming process. Because of the friction between the corn stalk powder and the die wall, the distance of deformation curve nearby the axial line was obviously greater than the deformation curve nearby the die wall. The paper also obtained the equivalent strain and load-displacement curve. The maximum axial strain was located at the upper portion of the compaction block where there was contact with the die wall. The strain increased along with the height of the die wall. The total load increased very quickly in the process of the plastic deformation, and the smaller deformation was needed to exert greater load. The relationship between the numerical results and the experimental results was analyzed using paired t-test and regression analysis. Paired t-test gave that P-value (Bilateral) of the large strain was greater than 0.05 and agreed well with the experimental results. This paper put forward the finite element model of large strain which can better describe the molding process of compression for cornstalk powder. The correlation coefficient between the results of the large strain and the experimental results was R2=0.9855, but the correlation coefficient between the results of the small deformation and the experimental results was R2=0.9398. The study indicated that the large deformation method has a higher calculating precision. The large deformation computation can adopt large step (0.01) and the step of the small deformation is 0.0001. The result showed that the computation efficiency is improved. The paper provides a reference for further study on the technology of cornstalk powder's molded compression, and the optimization design of techniques and equipment.
  Number of references:  28
  Main heading:  Compaction 
  Controlled terms:  Compression molding  -  Compression testing  -  Curricula  -  Deformation  -  Dies  -  Finite element method  -  Packaging materials  -  Plastic deformation  -  Regression analysis  -  Stiffness matrix  -  Straw 
  Uncontrolled terms:  Computation efficiency  -  Correlation coefficient  -  Design and technology  -  Finite deformation theory  -  Geometric nonlinear behavior  -  Load-displacement curve  -  Tangent stiffness matrix  -  Uni-axial compression tests 
  Classification code:  943 Mechanical and Miscellaneous Measuring Instruments -  922.2 Mathematical Statistics -  921.6 Numerical Methods -  901.2 Education -  821.5 Agricultural Wastes -  816.1 Processing of Plastics and Other Polymers -  694.2 Packaging Materials -  603.2 Machine Tool Accessories -  536.1 Powder Metallurgy Operations -  422 Strength of Building Materials; Test Equipment and Methods -  421 Strength of Building Materials; Mechanical Properties
  DOI:  10.3969/j.issn.1002-6819.2013.20.026
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 29>

Accession number:  20134616980325
 
  Title:  Calculation of live tree timber volume based on particle swarm optimization and support vector regression
  Authors:  Jiao, Youquan1, 2 Email author jiaoyouquan@163.com; Zhao, Lixi3; Deng, Ou4; Xu, Weiheng1, 5; Feng, Zhongke1 Email author fengzhongke@126.com 
  Author affiliation:  1 Institute of GIS, RS and GPS, Beijing Forestry University, Beijing 100083, China 
   2 Beijing Vocational College of Agriculture, Beijing 102442, China 
   3 Water Conservancy and Civil Engineering, China Agricultural University, Beijing 100083, China 
   4 Institute of Public Safety Research, Tsinghua University, Beijing 100084, China 
   5 College of Computer and Information Engineering, Southwest Forestry University, Kunming 650224, China 
  Corresponding author:  Feng, Z. (fengzhongke@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  160-167
  Language:  Chinese
  ISSN:  10026819 
  CODEN:  NGOXEO 
  Document type:  Journal article (JA)
  Publisher:  Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
  Abstract:  Establishment of each tree species volume table is an important research subject in forest management. Accurate tree tables were used to determine the forest reserves. Moreover, these tree tables were applied to provide precise forest management decision making references for the forestry center and local forestry authorities. However, because of the difference of increment between different tree species, live tree tables must be revised every 10 years in China. Previously, to establish tree tables, sample trees were selected in the local area according the corresponding rules, and these sample trees were cut down and divided into several sections, and each section's volume were summed up as the total tree volume. Based the analytic data, the unary models between diameter at breast and volume were established, and also, to set diameter at breast and tree height as independent variables, tree volume as dependent variable, the binary models could be established, as well as a ternary model that describes the relationship between volume and 3 independent variables including diameter at breast, tree height, and tree step form. Nevertheless, these models mentioned above are sample linear models or nonlinear models. To estimate the forest stocks in the forest survey, former researchers usually cut down target trees and extracted samples based on the principle of sampling, and then made a corresponding volume table. This felled, destructive, and time-consuming method damaged many growth dominant trees. Tree volume modeling is the key step of volume table establishment, and volume usually was predicted by the volume equation that was derived from experience. However, because of the uncertainty of tree growth, it is difficult to effectively predict the complexity and diversity of the volume model through conventional volume equations. For this reason, the volume prediction accuracy rate is unsatisfactory. In order to promote the volume prediction accuracy rate, the algorithm of particle swarm optimization (PSO) was introduced into the standing tree volume prediction model. Moreover, the parameters were optimized by the support vector regression (SVM). The data of diameters at breast height and tree heights of standing trees were input into SVM, which were used to learn, parameters of SVM were used as the particle of PSO, standing trees volume value that were measured by authors were considered as objective function of PSO, then prediction values of standing trees volume were detected by the optimized parameters which were obtained through mutual co-ordination of particle, and the prediction values of standing trees' volume were verified by the measured value. This research first applied electronic theodolite and artificial measurement to get the stumpage diameter and breast diameter of 400 samples; and then considered stumpage diameter and breast diameter as input data, volumes as output data, trained with 300 samples by PSO-SVM; and finally, compared the results by PSO-SVM, Spurr volume model, and BP neural network by predicting 100 samples. The results showed that PSO-SVM, which showed the highest correlation coefficient between the predicted and measured values (0.91) and lowest average error rate (0.58%), was better than the others.
  Number of references:  28
  Main heading:  Forestry 
  Controlled terms:  Binary trees  -  Calculations  -  Forecasting  -  Models  -  Neural networks  -  Particle swarm optimization (PSO)  -  Research  -  Timber 
  Uncontrolled terms:  Correlation coefficient  -  Diameters at breast heights  -  Electronic theodolite  -  Independent variables  -  Management decision-making  -  Pso-svm  -  Support vector regression (SVR)  -  Trees 
  Classification code:  921 Mathematics -  902.1 Engineering Graphics -  901.3 Engineering Research -  921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory -  821.0 Woodlands and Forestry -  721 Computer Circuits and Logic Elements -  415.3 Wood Structural Materials -  723 Computer Software, Data Handling and Applications
  DOI:  10.3969/j.issn.1002-6819.2013.20.022
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 30>

Accession number:  20134616980322
 
  Title:  Early prediction of antioxidant enzyme value of rice blast based on hyper-spectral image
  Authors:  Yang, Yan1, 2 Email author y_yae@163.com; He, Yong1 Email author yhe@zju.edu.cn 
  Author affiliation:  1 School of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou 310029, China 
   2 College of Mathematics Science, Guangxi Teachers Education University, Nanning 530023, China 
  Corresponding author:  He, Y. (yhe@zju.edu.cn) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  135-141
  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 rice blast is a fungal disease which can damage the rice cultivation and reduce the yields at least by 40% to 50% in the worst period. The early detection of rice blast is an effective mean to control the disease spread. The present paper is concerned with the study of the early prediction of antioxidant enzyme value SOD of rice blast based on hyper-spectral images within the incubation period. The aim of study is to realize the rice blast early detection through monitoring the antioxidant enzyme SOD activity variation. The hyper-spectral system operated in the visible and short-wave near infrared range was applied for non-invasive determination of antioxidant enzyme value SOD. The hyper-spectral images of rice canopy were obtained in six separated time periods (0, 12, 24, 36, 48, 60 hours) after vaccination, and the antioxidant enzyme value SOD of canopy in different inoculation time were measured using chemical method synchronously. For each hyper-spectral image, the rice seedlings were extracted using threshold segmentation method and average spectrum of rice seedling were calculated. The each average spectrum was considered as a sample, therefore, there are 150 hyper-spectral images which would product 150 samples. The all of samples were divided into two sets: calibration sets which included 100 samples and prediction sets which included 50 samples. The hyper-spectral images were used to construct prediction model of antioxidant enzymes SOD activity with chemometrics methods. The different spectrum pre-processing methods were applied, including the first derivative, the second derivative, Savitzky-Golay smoothing and Direct Orthogonal Signal Correction (DOSC). After pre-processing, the Partial Least Square (PLS) method based on full spectrum was used to train the calibration sets and predict the predictive sets. The results showed that the DOSC-PLS could produce the best prediction. The DOSC-PLS model yields a reasonable accuracy with RC=0.9682, RMSEC=6.225 U/g for calibration and with RP=0.8665, RESEP=12.82 U/g for prediction respectively; Instead of using a wide range of spectra, the number of wavebands was reduced for more stable, comprehensive and faster model in the subsequent multispectral imaging system. From this point of view, important wavelengths were selected to simplify the model. On the basis of analysis of PLS, the loading method was used to select feature wavelengths base on the first five principal components which cover the 92% information of original spectrum. Six wavelengths (526, 550, 672, 697, 738 and 747 nm) were selected as the feature wavelengths for SOD prediction with PLS regression. With the identified reduced number wavelengths, the RC=0.6945, RMSEC=17.92 U/g for calibration and RP=0.5488, RESEP=22.0085 U/g for prediction were achieved. In spite of the prediction ability based on feature wavelengths was depressed, but the feasibility of simplified model has been confirmed. The subsequent study will take a closer look at the improvement of prediction ability based on a few feature wavelengths. All in all, the results shown that it is feasible to predict SOD enzyme activity variation for evaluating stress degree of rice blast based on hyper-spectral images within the incubation period.
  Number of references:  30
  Main heading:  Forecasting 
  Controlled terms:  Antioxidants  -  Calibration  -  Enzymes  -  Image processing  -  Image segmentation  -  Loading  -  Models  -  Principal component analysis  -  Signal processing  -  Spectroscopy  -  Wavelength 
  Uncontrolled terms:  Antioxidant enzyme  -  Direct orthogonal signal corrections  -  Hyper-spectral images  -  Incubation periods  -  Multi-spectral imaging systems  -  Partial least square (PLS)  -  Plant disease  -  Threshold segmentation 
  Classification code:  804 Chemical Products Generally -  804.1 Organic Compounds -  902.1 Engineering Graphics -  944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments -  922.2 Mathematical Statistics -  942 Electric and Electronic Measuring Instruments -  943 Mechanical and Miscellaneous Measuring Instruments -  941 Acoustical and Optical Measuring Instruments -  803 Chemical Agents and Basic Industrial Chemicals -  801.2 Biochemistry -  672 Naval Vessels -  711 Electromagnetic Waves -  716.1 Information Theory and Signal Processing -  741 Light, Optics and Optical Devices -  741.1 Light/Optics -  801 Chemistry
  DOI:  10.3969/j.issn.1002-6819.2013.20.019
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 31>

Accession number:  20134616980331
 
  Title:  Effect of torrefaction on characteristics of pyrolytic products of biomass
  Authors:  Yang, Qing1; Mei, Yanyang1; Hao, Hongmeng1; Yang, Haiping1 Email author yhping2002@163.com; Wang, Xianhua1; Chen, Hanping1 
  Author affiliation:  1 State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074, China 
  Corresponding author:  Yang, H. (yhping2002@163.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  214-219
  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 pyrolysis of biomass is one of the promising methods for obtaining bio-energy, and is discussed widely. Bio-oil obtained from pyrolysis is easy to store and transport, and can be used directly and indirectly as a fuel. However, bio-oils have high acid content, high water content, and low heating value. These drawbacks have limited the broad application of bio-oils. Torrefaction is a low temperature pyrolysis process carried out at temperatures ranging from 200 to 300°C for liberating water and releasing volatile organic compounds, which may affect the subsequent pyrolysis process and related products. In this sense, there has been significant increase of interest in biomass torrefaction techniques. In this work, torrefaction of cotton stalk was conducted on a tube furnace at 200, 230, 260, 290°C with a residence time of 30 min. Pyrolysis of torrefied cotton stalk was also performed on a tube furnace reactor at 550°C with a residence time of 30 min. The effect of torrefaction temperature on the yield, products composition, and physical properties of bio-oil were studied. In addition, the product distribution of torrefied cotton stalk pyrolysis was also investigated. Torrefied cotton stalk was chosen as the benchmark when calculate the yield.The gas products of pyrolysis were analyzed by chromatograph (GC), and liquid products were analyzed by gas chromatography mass spectrometry (GC-MS) and Karl Fischer moisture tester. The research results showed that increasing torrefaction temperature resulted in the increase of the carbon content of torrefied biomass from 46.07% to 62.63%. However, the hydrogen and oxygen contents decreased from 7.06% to 5.26% and 41.26% to 24.84%, respectively. With the increase of torrefaction temperature, the cotton stalk gradually converted to charcoal. The highest calorific value was 24.85 MJ/kg when torrefaction was performed at 290°C. The solid yield of pyrolysis was decrease sharply with elevated torrefaction temperature, which was in contrary to the liquid yield, while gas yield had no obvious change. As for pyrolysis of gases, the content of H2 and CH4 increased with elevated torrefaction temperature, and the yield of H2 increased by 77.4%, the content of CO decreased from 48% to 34%, the yield of CO2 had no obvious change. However, the total content of combustible gases increased. As for liquid production, with the increasing torrefaction temperature, the yield of liquid was decreased by 3.4%, 17.6%, 25.0%, 42.8% compared to the raw biomass. Water and acetic acid content in bio-oil decreased greatly while the quantity of polycyclic aromatic compounds increased, which indicated that torrefaction could improve the quality of bio-oil, and provide process optimization for subsequent fast pyrolysis.
  Number of references:  32
  Main heading:  Pyrolysis 
  Controlled terms:  Aromatic compounds  -  Biofuels  -  Biomass  -  Calorific value  -  Carbon dioxide  -  Cellulose  -  Charcoal  -  Cotton  -  Gas chromatography  -  Lignin  -  Liquids  -  Optimization  -  Residence time distribution  -  Tubes (components)  -  Volatile organic compounds 
  Uncontrolled terms:  Bio oil  -  Gas chromatography-mass spectrometry  -  High water content  -  Low-temperature pyrolysis  -  Polycyclic aromatic compounds  -  Product distributions  -  Pyrolytic products  -  Torrefaction 
  Classification code:  931.2 Physical Properties of Gases, Liquids and Solids -  804.1 Organic Compounds -  804.2 Inorganic Compounds -  815.1.1 Organic Polymers -  819.1 Natural Fibers -  921.5 Optimization Techniques -  922.1 Probability Theory -  802.2 Chemical Reactions -  616.1 Heat Exchange Equipment and Components -  525.1 Energy Resources and Renewable Energy Issues -  524 Solid Fuels -  523 Liquid Fuels -  522 Gas Fuels -  801 Chemistry
  DOI:  10.3969/j.issn.1002-6819.2013.20.028
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 32>

Accession number:  20134616980313
 
  Title:  Trimming law and mechanism of efficiency decrease in double-suction centrifugal pump with cut impeller
  Authors:  Leng, Hongfei1 Email author lenghongfei@126.com; Wang, Fujun1 Email author wangfj@cau.edu.cn; Yao, Zhifeng1; Ma, Yafei1 
  Author affiliation:  1 College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China 
  Corresponding author:  Wang, F. (wangfj@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  67-73
  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:  Double-suction centrifugal pumps are widely used in water diversion, irrigation, drainage, and water supply engineering. In order to save energy, pump impellers often are cut a little if a double suction centrifugal pump head is much higher than the required one in a water delivery system. To investigate the influence of impeller cutting on the hydraulic performance of a double suction centrifugal pump, a general three-dimensional simulation of turbulent fluid flow was presented. The RNG κ-Ε turbulence model and SIMPLEC arithmetic were adapted to analyze the external characteristics and the internal flow field of the pump equipped with a cut impeller. The impeller was trimmed seven times successively in this study, then all the cut impellers were installed into a 20SH9 type pump casing respectively. The entire computational domain was divided into 1700000 grid cells. According to the simulation results, it was found that with the increase of the cutting value, the pump operating point on the performance curve significantly moved towards the lower flow rate, and the best efficiency gradually decreased. The hydraulic losses induced by the impeller trimming were mainly generated inside the impeller. The vortex area in the impeller flow passage increased after impeller cutting due to the weak control of the blades over the flow. On the other hand, the increase of the tongue gap did not result in the increase of the hydraulic loss in the volute. This study also found that for a fixed cutting value, the pump head and shaft power predicted by CFD were approximately equal to the value calculated by the conventional trimming law at large flow rates. However, the pump head and shaft power were over-predicated by the conventional trimming law at low flow rates. Therefore, the impeller cutting values should not be selected simply by the trimming law if a double-suction centrifugal pump often runs at low flow conditions. The results of this study provide new references for the efficient operation of a double suction centrifugal pump in engineering applications.
  Number of references:  26
  Main heading:  Trimming 
  Controlled terms:  Centrifugal pumps  -  Computer simulation  -  Efficiency  -  Flood control  -  Flow rate  -  Impellers  -  Pumps  -  Turbulence models  -  Water supply 
  Uncontrolled terms:  Computational domains  -  Double-suction centrifugal pumps  -  Engineering applications  -  External characteristic  -  Hydraulic performance  -  Three dimensional simulations  -  Water delivery systems  -  Water supply engineering 
  Classification code:  913.1 Production Engineering -  723.5 Computer Applications -  631.1 Fluid Flow, General -  631 Fluid Flow -  618.2 Pumps -  601.2 Machine Components -  535.1.2 Rolling Mill Practice -  454.1 Environmental Engineering, General -  446.1 Water Supply Systems
  DOI:  10.3969/j.issn.1002-6819.2013.20.010
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 33>

Accession number:  20134616980328
 
  Title:  Effect of steam explosion pretreatment on ensiling performance of dry corn stover
  Authors:  Jia, Jingxia1 Email author jiajingxia@126.com; Liang, Baozhong1; Wang, Yanhong1; Zhao, Yongliang1; Li, Jiandong1 
  Author affiliation:  1 Chinese Academy of Agricultural Mechanization Sciences, Beijing 100083, China 
  Corresponding author:  Jia, J. (jiajingxia@126.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  192-198
  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:  Ensiling is an important crop straw feed processing method. It can not only effectively improve the nutritional value of crop straws, but also increase the storage time. Currently the corn and silage corn cultivated areas are 3.35×107 and 2.083×106 hm2 in China. The corn stover (CS) annual production is about 260 million tons. However, due to the requirements of the moisture content and freshness, only the un-harvested or newly harvested CS can be used as ensiling. This limits the operation time of ensiling and the scope of CS. In order to expand the available range of CS and reduce the unnecessary use of additives, the advantages of three straw feed processing methods of silage, microbial silage and steam explosion were studied. On these bases, the feasibility of improving dry CS ensiling performance by steam-explosion pretreatment was tested in this work. First, the dry CS was cut into 3-5 cm, adjusted the moisture content to 50% (w/w) and pretreated under different intensities (0.8-1.4 MPa, 5 min) in a 5 L steam explosion reactor. The steam-exploded CS was water-washed to remove the soluble fraction. Then the structural components of cellulose, hemicellulose and Klason lignin in the solid residual and the soluble sugar, acetic acid and furfural in the water-washed liquor were determined according to the two-step quantitative hydrolysis method recommended by National Renewable Energy Laboratory (NREL). Based on these data, the material recovery ratio was calculated to evaluate the efficiency of steam explosion pretreatment. Then, the pretreated and un-pretreated CS samples were used in ensiling experiments. In addition to water, any microbial inoculants and enzyme was not used. The samples including control samples were added tap water according to the real moisture content and adjusted the final moisture content to 70% (w/w). Each 5 kg sample was loaded in a sealed plastic bag and ensilaged in 15-25°C. Throughout the experiment, silage feed pH value, organic acids and volatile basic nitrogen (VBN)/total nitrogen were determined from the periodic sampling (5, 15, 30 and 60 d). After six months ensiling, the silages were scored according to the Silage Quality Assessment Criteria issued by the Chinese Ministry of Agriculture. The results showed that the steam explosion pretreatment could degrade the hemicellulose in CS and increase the oligosaccharides and monosaccharides content in CS. According to the pretreatment intensity, the soluble sugars content in the CS increased from 17.51% to 19.58%-25.77%. At the same time, the pH value of raw materials decreased from 7.09 to 6.14-4.26. The saccharide produced during the pretreatment played a positive role to lactic acid bacteria growth in the ensiling. The silage pH value, the proportion of VBN/total nitrogen decreased significantly, and the feed quality was improved. The pretreated CS from the optimum conditions (1.0 MPa and 5 min) increased its final score from 50 (normal) to 83 (excellent). The results also showed that higher pretreatment intensity could not only increase the soluble sugar content, but also the furfural content in the pretreated CS. When the pretreated steam pressure was higher than 1.0 MPa, the furfural production increased significantly. Furfural made the pretreated CS smelled pungent, also affected the microorganisms growth. So, for the final quality of silage, the suitable steam explosion pretreatment intensity choice was very important. Low intensity steam explosion pretreatment made the dry CS obtaining a good ensiling performance, and which expanding the ensiling substrates range.
  Number of references:  32
  Main heading:  Steam 
  Controlled terms:  Aldehydes  -  Cellulose  -  Crops  -  Digital storage  -  Experiments  -  Explosions  -  Furfural  -  Moisture determination  -  Nitrogen  -  pH  -  Plastic containers  -  Straw 
  Uncontrolled terms:  Ensile  -  Final moisture content  -  Hydrolysis methods  -  Lactic acid bacteria  -  Microbial inoculants  -  National Renewable Energy Laboratory  -  Soluble sugar contents  -  Structural component 
  Classification code:  944.2 Moisture Measurements -  901.3 Engineering Research -  821.5 Agricultural Wastes -  821.4 Agricultural Products -  815.1.1 Organic Polymers -  804.1 Organic Compounds -  804 Chemical Products Generally -  801.1 Chemistry, General -  722.1 Data Storage, Equipment and Techniques -  694 Packaging -  691 Bulk Handling and Unit Loads -  614 Steam Power Plants -  502.1 Mine and Quarry Operations
  DOI:  10.3969/j.issn.1002-6819.2013.20.025
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 34>

Accession number:  20134616980309
 
  Title:  Optimal design for cone valve of mechanical-hydraulic dual power engine
  Authors:  Huo, Wei1 Email author qdhuowei@163.com; Zhang, Jipeng1; Zhang, Hongxin1; Zhang, Tiezhu1 
  Author affiliation:  1 College of Mechanical and Electronic Engineering, Qingdao University, Qingdao 266071, China 
  Corresponding author:  Huo, W. (qdhuowei@163.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  40-45
  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:  Heat energy can be converted to hydraulic energy by a traditional engine-pump system (EPS). However, the EPS has some disadvantages, such as a long transmission line, low efficiency, and a complex and heavy structure. With an integrating traditional internal combustion engine and plunger pump to remove intermediate links, a mechanical-hydraulic dual power engine (MHPE) can convert heat energy to hydraulic energy directly. Therefore, the energy conversion efficiency was improved and the structure was simplified. MHPE can output one of or both machinery and hydraulic powers, and it can be used for excavators, loaders, bulldozers, and other engineering machineries. The distribution valve, the important element of MHPE, can affect the volume efficiency of the system directly by its structure and performance. The 36114ZG4B type six-cylinders radial MHPE was developed. A-H20L type one-way cone valve with the valve disk of 0.07557 kg quality, 0.028 m large diameter, 0.021 m small diameter and 40° angle is used as an inlet valve. A DIF-L20H type one-way cone valve with the valve disk of 0.04672 kg quality, 0.021 m large diameter, 0.016 m small diameter and 45° angle was used as an outlet valve. With the volume efficiency taken as an objective function, the cone valve's working conditions and structure dimensions taken as constraint conditions, and the cone valve's structure parameters taken as optimization variables, an optimization model was established. Based on Adolph's no-impact theory of pump valve, a valve disk's speed cannot exceed the maximum allowable speed. In order to guarantee the normal work of the valve cone, the hydraulic oil's flow rate through valve clearance is not allowed to exceed 6 m/s. iSIGHT software was used to optimize the cone valve's structure with the inlet valve disk result of 0.04076 kg, 0.036 m large diameter, 0.028 m small diameter, and 46° angle as well as the outlet valve disk result of 0.05845 kg, 0.028 m large diameter, 0.021 m small diameter and 49° angle. At the same time, the volume efficiency of the system was simulated and has been found to increase significantly with the optimization: the volume efficiency increased by 5.71% to the maximum point, 98.06%, at about 1300 r/min; the volume efficiency of the system decreased when the rotate speed exceeded 1 300 r/min, which is due to the cone valve's natural frequency is close to the integer times of the operating frequency of the system; and the volume efficiency is stable in the common condition area, which was from 1200 to 1400 r/min.
  Number of references:  27
  Main heading:  Valves (mechanical) 
  Controlled terms:  Earthmoving machinery  -  Energy conversion  -  Engines  -  Hydraulic machinery  -  Integer programming  -  Internal combustion engines  -  Optimization  -  Pumps 
  Uncontrolled terms:  Constraint conditions  -  Dual power  -  Engineering machinery  -  Long transmission lines  -  Optimization modeling  -  Optimization variables  -  Structure and performance  -  Volume efficiency 
  Classification code:  632.2 Hydraulic Equipment and Machinery -  618.2 Pumps -  612.1 Internal Combustion Engines, General -  921.5 Optimization Techniques -  612 Engines -  525.5 Energy Conversion Issues -  405.1 Construction Equipment -  601.2 Machine Components
  DOI:  10.3969/j.issn.1002-6819.2013.20.006
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 35>

Accession number:  20134616980327
 
  Title:  Application of GC-TOPSIS on optimizing choice of utilization programs of crop straw
  Authors:  Yang, Zengling1 Email author yangzengling@cau.edu.cn; Chu, Tianshu1; Han, Lujia1 Email author hanlj@cau.edu.cn; Liu, Xian1; Xiao, Weihua1; Huang, Guangqun1 
  Author affiliation:  1 College of Engineering, China Agricultural University, Beijing 100083, China 
  Corresponding author:  Han, L. (hanlj@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  179-191
  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:  Crop straw is an important biomass resource. The comprehensive utilization of crop straw not only protects the environment of producing areas and increases the farmers' income, but also lays foundation for circular economy and emerging industry. The main utilization approaches for crop straw are converting to animal feed, fertilizer, fuel, material of edible fungi, and material of industry. In order to optimize the utilization approaches of crop straw, the evaluation indices are assigned based on information from references, which are measured by nine grade assignment. The evaluation indices are formed by functional indices, economical beneficial indices, environment beneficial indices and adaptability indices. The functional indices are formed by maturity of engineering and effective transformation of engineering. The economical beneficial indices are formed by the utilization cost of crop straw per ton and the benefit of resource substitution per ton. The indices of environmental benefit are formed by the profit of waste reduction per ton and the secondary pollution degree per ton. The adaptability indices are formed by the coordination degree of regional crop straw variety, the coordination degree of regional crop straw density, the coordination degree of regional crop straw collection, transportation, storage and the coordination degree of regional policy planning. The combination weights method based on entropy and rank correlation analysis method is used to obtain the weights of evaluation index, and GC-TOPSIS (technique for order preference by similarity to ideal solution combined by grey correlation) serves as decision-making method. The combination weighting method gives consideration for both subjective and objective influencing factors, by comparing with simple subjective weighting method or objective weighting method, which is scientific, easy, and feasible. GC-TOPSIS method is a new kind of relative similarity degree by combining the Euclidean distance with grey correlation degree. It reflects the distances and the different shapes among a selected scheme, the ideal solution and negative ideal solution. The implication is clearer, valid and feasible. And these methods are applied to the optimization of utilization approaches of crop straw in Heilongjiang province. The preference order of five utilization approaches obtained for Heilongjiang province in this paper is: as feed > as fertilizer > as fuel > as material of edible fungi > as material of industry, which is consistent with actual development and scheme in Heilongjiang province. At the same time, the optimization method provides foundation to scheme the various choices of utilization approaches in Heilongjiang province. Furthermore, the evaluation indices are assigned by information from the reference, which is practicable and gives access to optimized choices.
  Number of references:  173
  Main heading:  Crops 
  Controlled terms:  Application programs  -  Decision theory  -  Fertilizers  -  Fungi  -  Optimization  -  Scheduling 
  Uncontrolled terms:  Combination weighting method  -  Combination weights  -  Comprehensive utilizations  -  GC-TOPSIS  -  Grey correlation degrees  -  Rank correlation analysis method  -  Relative similarity degrees  -  Technique for order preference by similarity to ideal solutions 
  Classification code:  921.5 Optimization Techniques -  921 Mathematics -  912.2 Management -  961 Systems Science -  821.4 Agricultural Products -  723 Computer Software, Data Handling and Applications -  461.9 Biology -  804 Chemical Products Generally
  DOI:  10.3969/j.issn.1002-6819.2013.20.024
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 36>

Accession number:  20134616980306
 
  Title:  Design and test on self-cleaning seeding head for mechanism suction
  Authors:  Jiang, Kai1 Email author jiangk@nercita.org.cn; Zhang, Qian2; Wang, Xiu1 Email author wangx@nercita.org.cn 
  Author affiliation:  1 Beijing Research Center of Intelligent Equipment for Agriculture, Beijing 100097, China 
   2 Beijing Research Center for Information Technology in Agriculture, Beijing 100097, China 
  Corresponding author:  Wang, X. (wangx@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:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  18-23
  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 China, the cultivation area of the facilities agriculture has reached 3.5 million hectares, and the industrialized farming will continue to develop during the period of the 12th "Five-Year Plan". The demand for intelligent equipment of facilities agriculture has become increasingly urgent with the rapid development of the ageing of population and the lacking of labor in rural areas of China. As for the air-suction seeders, there were many researches on positive pressure methods for dredging and ejecting seed head, but few reports about the research on the technology to prevent the seeding head blockage. The needle-type tray seeder consisted of seeding head, seeding pole, conveying cylinders, seeds plate, pneumatic vibrator, guide pipe, conveyor belt and so on. The seeds plate and pneumatic vibrator provide exciting force to boil the seeds to make the seeds being absorbed easily. Operations of absorbing the boiling seeds from the seeds plate and transporting the seeds to the guide pipe were implemented by the seeding head, seeding pole, conveying cylinders and guide pipe. In order to solve the problem that the suction nozzle of needle-type tray seeder was easily blocked to affect the quality of sowing, a kind of mechanical self-cleaning seeding head was designed based on air suction-blowing seeding principle. The structure of mechanical self-cleaning seeding head consists of a nozzle tip, fixed base, cleaning piston, thimble and reset spring and other parts. The suction nozzle was dredged by cleaning piston, and the seeding operation was performed by the thimble. The mechanical models that seeds were drawn at negative pressure and ejected mechanically at positive pressure were developed. The analysis results showed that the suction airflow rate was directly proportional to the inside diameter of the suction nozzle and inversely proportional to the height of suction position. The pressure of ejecting seed depended on the compression force of the reset spring, the gravity and adsorption force of seed. While the height of suction position was fixed, the negative pressure for sucking seed was negatively related to the inside diameter of the suction nozzle. While the inside diameter of the suction nozzle was constant, the negative pressure for sucking seed was positive correlated with the height of suction position. The experimental results showed that while the speed of seeding is 40 rows per minute, pickup vacuum is 35 kPa, shooting-seed pressure is 50 kPa, the single seed rate, cavity rate and repeat seeding rate were 95.31%, 1.56% and 3.13% respectively, which increased by 7.81%, 6.25% and 1.56% respectively than traditional suction nozzle. The quality of sowing and effects of anti-blocking were improved significantly, so the self-cleaning seeding head can replace the traditional needle-type suction nozzle. The research can provide a reference for further improving quality and optimizing the parameter for self-cleaning seeding head.
  Number of references:  29
  Main heading:  Air cleaners 
  Controlled terms:  Air ejectors  -  Belt conveyors  -  Cleaning  -  Cultivation  -  Cylinders (shapes)  -  Design  -  Needles  -  Nozzles  -  Pneumatic control equipment  -  Poles  -  Research  -  Rural areas  -  Testing 
  Uncontrolled terms:  Compression force  -  Intelligent equipment  -  Mechanical model  -  Negative pressures  -  Pneumatic vibrators  -  Positive pressure  -  Seeder  -  Self-cleaning 
  Classification code:  901.3 Engineering Research -  821.3 Agricultural Methods -  821 Agricultural Equipment and Methods; Vegetation and Pest Control -  819.6 Textile Mills, Machinery and Equipment -  802.3 Chemical Operations -  732.1 Control Equipment -  692.1 Conveyors -  651.2 Wind Tunnels -  631.1 Fluid Flow, General -  618.3 Blowers and Fans -  423.2 Non Mechanical Properties of Building Materials: Test Methods -  408.2 Structural Members and Shapes -  408 Structural Design
  DOI:  10.3969/j.issn.1002-6819.2013.20.003
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.

<RECORD 37>

Accession number:  20134616980318
 
  Title:  Effects of maize straw mulch on spatiotemporal variation of soil profile moisture and temperature during freeze-thaw period
  Authors:  Chen, Junfeng1 Email author 13934247805@163.com; Zheng, Xiuqing1 Email author zxq6818@sina.com; Qin, Zuodong2; Liu, Ping1; Zang, Hongfei1; Sun, Ming3 
  Author affiliation:  1 College of Water Resources Science and Engineering, Taiyuan University of Technology, Taiyuan 030024, China 
   2 Institute of Loess Plateau, Shanxi University, Taiyuan 030006, China 
   3 Taigu Water Balance Experimental Field, Bureau of Hydrology and Water Resources Survey of Shanxi Province, Taigu 030800, China 
  Corresponding author:  Zheng, X. (zxq6818@sina.com) 
  Source title:  Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
  Abbreviated source title:  Nongye Gongcheng Xuebao
  Volume:  29
  Issue:  20
  Issue date:  October 15, 2013
  Publication year:  2013
  Pages:  102-110
  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:  Straw mulch has not only a positive effect, but also some negative effects during the seasonal freeze-thaw period. Straw mulch weakens the heat and moisture transfer between the soil and air, and it will go against the crop if the soil temperature rises slowly in the spring. With the aim of revealing the temporal and spatial variation of the soil profile moisture and temperature under different maize straw mulch thicknesses during the seasonal freeze-thaw period, a field experiment was conducted from November in 2005 to March in 2006 at Taigu Water Balance Experimental Field, Bureau of Hydrology and Water Resources Survey of Shanxi Province. Maize straw at rates of 2100 kg/hm2 (mulching thickness was 5 cm), 4300 kg/hm2 (mulching thickness was 10 cm), 6500 kg/hm2 (mulching thickness was 15 cm), 8600 kg/hm2 (mulching thickness was 20 cm) and 12900 kg/hm2 (mulching thickness was 30 cm) was placed on field plots (JD05 JD10, JD15, JD20, JD30). The soil profile moisture and temperature contours of the bare plot (LD) and five kinds of maize straw mulching thickness plots were compared. The temporal and spatial variation of the soil profile moisture and temperature were analyzed according to a statistical analysis. The results showed that the maximum frozen depth of LD was 52 cm, and the soil profile moisture and temperature of LD varied more dramatically during the seasonal freeze-thaw period and the depth of 0 to 40 cm was an active layer of water and temperature variation (ALWT) and the higher moisture zone (HMZ) appeared at the depth of 20 to 45 cm. However, the maximum frozen depth of JD05 and JD10 was 23 and 10 cm respectively that lagged from LD by about 15 days. For JD05, the depth of 0 to 20 cm was ALWT and HMZ (maximum soil moisture content was 22.5%) appeared at the depth of 15 to 25 cm. For JD10, the depth of 0 to 10 cm was ALWT and HMZ (maximum soil moisture content was 21.3%) appeared at the depth of 5 to 10 cm. Influenced by soil freezing-thawing and maize straw mulching, the effect of soil moisture conservation was best when maize straw mulching thickness was 5 cm, and the soil moisture content of the cultivated layer (from 0 to 20 cm) was 18% to 21%, which was higher than that of other plots. When maize straw mulching thickness was up to 15 cm, the variation of the soil profile moisture and temperature was small and it had the best effect of heat preservation, the soil profile temperature changed relatively stably and the minimum temperature reached 1.1°C. When maize straw mulching thickness exceeded 15 cm, the effect of soil moisture conservation and heat preservation was less obvious with the increasing of maize straw mulching thickness. Therefore, to aim at prevention of frost damage and conservation of soil moisture, the best maize straw mulching thickness is 10 to 15 cm. The research results tend to provide a reference for scientific maize straw mulching on farmland in a seasonal freeze-thaw area during winter and spring.
  Number of references:  34
  Main heading:  Freezing 
  Controlled terms:  Moisture  -  Moisture control  -  Moisture determination  -  Soil mechanics  -  Soil moisture  -  Soils  -  Statistical methods  -  Temperature  -  Water conservation  -  Water resources 
  Uncontrolled terms:  Freeze-thaw  -  Heat and moisture transfer  -  Hydrology and water resource  -  Maize straw  -  Moisture conservation  -  Spatio-temporal variation  -  Temperature variation  -  Temporal and spatial variation 
  Classification code:  944.2 Moisture Measurements -  922.2 Mathematical Statistics -  822.2 Food Processing Operations -  801.4 Physical Chemistry -  641.1 Thermodynamics -  483.1 Soils and Soil Mechanics -  444 Water Resources
  DOI:  10.3969/j.issn.1002-6819.2013.20.015
  Database:  Compendex
   Compilation and indexing terms, ? 2013 Elsevier Inc.