<RECORD 1>

Accession number:201436062554
Title:Laser imaging method for fast detecting white foreign fibers in cotton
Authors:Liu, Xiang (1); He, Xiangcheng (1); Su, Zhenwei (1); Liu, Feng (1); Wang, Dong (1); Gu, Qibiao (2)
Author affiliation:(1) School of Manufacturing Science and Engineering, Sichuan University, Chengdu, China; (2) DaYingXian Tian Jiao I/E Co., Ltd, Daying, China
Corresponding author:Su, Zhenwei
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:190-196
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Foreign fibers, such as polypropylene baler twine, packaging materials, ropes, small pieces of cloths, nylon, and other different synthetic fibers, are almost invariably present in cotton during the cotton picking, storing, drying, and transporting. Their presence in textile processing may cause a disastrous quality problem in the textile industry because their physical and chemical properties are different from cotton. In recent years, machine vision systems have been used for sorting out the foreign fibers from cotton, however, all of the sorting machines cannot efficiently identify white foreign fibers in cotton, because their color is the same or very similar under the illumination of visible light. The laser imaging method previously suggested by our team can distinguish most of the white foreign fibers from cotton based on the difference of the microstructure of the sample surface, but the successful detection rate was not high and the speed of the detection was slow. Because the method was based on the calculation of the target size and distribution, or in the image acquisition, the laser light must project from some special angles of the sample surface for the camera can obtain the reflected light from the white foreign fibers. In this study, the image contrast of the white foreign fibers and the cotton background was first quantized by the calculation of the average pixel value in a frame of the laser image. Then, under the illumination of a line laser at a fixed power and wavelength, the images of 12 kinds of typical white foreign fibers on the cotton surface were obtained by a camera with a fixed aperture with different lengths of exposure time. Finally, the relationship between the lengths of different imaging exposure time and the image contrast was analyzed. It was found that there was a shared wave crest in all of the relationship curves and imaging in the exposure time of the wave crest in the same frame image. The gray level of the white foreign fibers had reached a saturated status, but the gray level of cotton was still unsaturated. Thus, using an optimized exposure time, the difference of the gray level of the laser images can be used for the detection of the white foreign fibers in cotton, including white paper, white plastic film, white semitransparent plastic mulch, white cloth, white density foam plastic, white nylon cord, white cotton string, white plastic cord, white plastic cardboard, white semitransparent polypropylene bags, white polyethylene foamed sheets, and white feathers. The experimental results indicated that, by a simple binary segmentation algorithm, using the images obtained under the illumination of the line laser at the wavelength of 650 nm, a power of 0.8 W, and by the camera aperture of 8C with an exposure time of 1.6 ms, the 12 kinds of white foreign fibers can be easily distinguished from cotton. In Matlab, the processing time of a frame image was less than 3 ms, and the successful detecting rate was up to 95.8 percent. In conclusion, a fast imaging method based on line laser and optimized exposing time was presented in the study, which can be used for on-line detection of white foreign fibers in cotton.
Number of references:19
Main heading:Cotton
Controlled terms:Cameras - Computer vision - Fibers - Identification (control systems) - Image processing - Image segmentation - Light - Packaging materials - Polyamides - Polypropylenes  - Rayon - Textile industry - Twine
Uncontrolled terms:Binary segmentation - Exposure - Foreign fiber - Laser imaging - Machine vision systems - On-line detection - Physical and chemical properties - Polypropylene bags
Classification code:694.2 Packaging Materials - 731.1 Control Systems - 731.6 Robot Applications - 741 Light, Optics and Optical Devices - 742.2 Photographic Equipment - 812 Ceramics, Refractories and Glass - 815.1.1 Organic Polymers - 817 Plastics and Other Polymers: Products and Applications - 819 Synthetic and Natural Fibers; Textile Technology
DOI:10.3969/j.issn.1002-6819.2014.15.025
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 2>

Accession number:201436062563
Title:Catalytic pyrolysis of rape straw for upgraded bio-oil production using HZSM-5 zeolite
Authors:Yu, Ning (1); Cai, Yixi (1); Li, Xiaohua (1); Fan, Yongsheng (1); Yin, Haiyun (1); Zhang, Rongxian (2)
Author affiliation:(1) School of Automotive and Traffic Engineering, Jiangsu University, Zhenjiang, China; (2) School of Chemistry and Chemical Engineering, Jiangsu University, Zhenjiang, China
Corresponding author:Cai, Yixi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:264-271
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Catalytic upgrading of the vapors from rape straw vacuum pyrolysis was conducted over HZSM-5 zeolite in a fixed bed reactor. Univariate analysis was employed in this study to investigate the effects of the operating parameters, including catalyst quality, Si/Al ratio of catalyst, and catalyzing temperature, on the product yields and the composition of upgraded bio-oil. Based on the univariate analysis, the preliminary operating parameters of catalytic reactor were optimized. The results showed that, when the catalyzing temperature was 500 and HZSM-5 (Si/Al=50) quality was 60 g, a lower oxygen content (27.97 percent), higher heating value (30.14kJ/kg-1), and a lower hydrogen-to-carbon ratio (0.12) were obtained. Moreover, the components of the obtained bio-oil contained a small amount of high oxygen contents, such as aldehydes, acids, and ketones. Meanwhile, phenols and aromatic hydrocarbons obviously increased. Product distribution and yield between upgraded bio-oil and crude bio-oil was also compared to study the catalytic refining effects and catalytic deoxygenation performance of HZSM-5 zeolite. This capacity of HZSM-5 zeolite was the key to make up for the two shortcomings of crude bio-oil, which were corrosivity and instability. The catalyst quality had significant effects on the properties of the upgraded bio-oil. Catalytic upgrading of pyrolysis vapors was incomplete when the catalyst quality was not high enough. However, when the catalyst quality was excessive, a decreased yield of upgraded oil resulted due to excessive secondary cracking reactions. In this study, the quality ratio of the catalyst to biomass was about 0.4. Catalyzing temperature also had an important effect on the properties of upgraded oil. When the catalyzing temperature was lower, the activation energy could not meet the needs of cracking reactions, and the catalytic effect was poor. When the catalyzing temperature was higher than optimal value, deactivation of the catalyst resulted because the structure of the catalyst was destroyed. Accordingly, the upgraded bio-oil with a higher gross heating value and lower oxygen content was obtained when the catalyzing temperature was about 500. The Si/Al ratio of the catalyst, which determined its density of acid sites and acid strength, had a great impact on catalytic product distribution. Four different Si/Al ratios of HZSM-5 were investigated. Upgraded bio-oil with a higher gross heating value and lower oxygen content was obtained when the Si/Al ratio of HZSM-5 was 50. Also, there were significant differences between upgraded bio-oil and crude bio-oil in product distribution and yield. The yield of crude bio-oil was 43.98 percent while the yield of upgraded bio-oil was 36.12 percent. Oxygenated components in the upgraded bio-oil, such as aldehydes, carboxylic acids, and ketones, which were 13.71 percent, 11.75 percent, and 13.59 percent, dropped significantly to 3.38 percent, 1.68 percent, and 4.48 percent, respectively. However, phenols containing lower oxygen and non-oxygenated hydrocarbons increased observably. These results showed that the HZSM-5 catalyst had a strong catalytic refining and catalytic deoxygenation capacity. Based on the results of this study, a catalytic reaction mechanism of HZSM-5 was proposed by comparing non-catalytic and catalytic bio-oil compositions. HZSM-5 was highly active in catalytic deoxidation. However, the online catalytic upgrading mechanism of bio-oil vapors was complex and it needs to be further studied in the future.
Number of references:32
Main heading:Catalytic cracking
Controlled terms:Activation energy - Aldehydes - Biofuels - Biomass - Calorific value - Catalysis - Catalyst deactivation - Catalysts - Cracks - Ketones  - Oil shale - Oxygen - Phenols - Pyrolysis - Quality control
Uncontrolled terms:Catalytic reaction mechanism - Component analysis - Different Si/Al ratio - H-ZSM-5 - Hydrogen-to-carbon ratio - Oxygenated components - Rape straws - Vacuum pyrolysis
Classification code:421 Strength of Building Materials; Mechanical Properties - 512.1 Petroleum Deposits - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 525.1 Energy Resources and Renewable Energy Issues - 801.4 Physical Chemistry - 802.2 Chemical Reactions - 804 Chemical Products Generally - 804.1 Organic Compounds - 913.3 Quality Assurance and Control
DOI:10.3969/j.issn.1002-6819.2014.15.034
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 3>

Accession number:201436062555
Title:Moving trace optimization tracking for adult of Bactrocera Dorsalis (Hendel) based on Kalman filter algorithm
Authors:Wen, Tao (1); Hong, Tiansheng (2); Li, Lijun (1); Zhang, Nanfeng (4); Li, Zhen (2); Guo, Xin (5)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Central South University of Forestry and Technology, Changsha, China; (2) Key Laboratory of Key Technology for South Agricultural Machinery and Equipment, College of engineering, South China agricultural University, Guangzhou, China; (3) Division of Citrus Machinery, China Agriculture Research System, Guangzhou, China; (4) Guangzhou Entry-exit Inspection and Quarantine, Guangzhou, China; (5) College of Science, Central South University of Forestry and Technology, Changsha, China
Corresponding author:Hong, Tiansheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:197-205
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Bactrocera Dorsalis (Hendel) are invasive pests which occur frequently and are seriously harmful to the growth of fruit trees, and they have been ranked an important quarantine object in many countries and regions. The regular manual survey used as the routine predicting method for Bactrocera Dorsalis (Hendel) has not accomplished the requirement of real-time and precise monitoring and warning by means of the adult trapping and monitoring device deployed in orchards. With the development of science and technologies, the method of the automatic machine monitoring for pests has been studied including detection of sound characteristics, radar monitoring and spectral monitoring. Considering the characteristic with randomness, migratory and hiding for Bactrocera Dorsalis (Hendel), there were some problems such as timing, processing and costs in monitoring pests with the aid of combining the above monitoring and the traditional method. In order to accomplish precise monitoring for Bactrocera Dorsalis (Hendel), machine vision technologies were used as an in-field automatic detecting method for the Hendel adults in this paper. Considering the problem with tracking Bactrocera Dorsalis (Hendel) object disappearance in multi-objects with more closer condition by means of the mean shift algorithm in color space according to previous machine vision technology research results, the fusion algorithm based on mean shift and Kalman filter theories for moving objects was proposed for optimizing multi-objects moving trace tracking by means of colorful analysis for moving objects and background in monitoring zones. The recurrence relation of the adults moving trace was obtained, and position coordinate, X-component and Y-component of speed in the 2D plane were extracted by image processing and matching technologies in this algorithm. By analyzing the state sequence linear minimum variance estimate theory of dynamic system and recurrence relation of the adults moving trace, the model of state estimate based on a Kalman filter was built to achieve the position estimation of the adults using the prediction and modified equation of the model. The experiment of the adults tracking under the condition of single object and the condition of multi-objects with scatter and gathering indicated that the mean shift algorithm was adaptive to track the adults in the condition of single object with monitoring precision of 100%, was not adaptive to the condition of multi-objects with scatter and gathering since corresponding monitoring precisions were 86% and 76% respectively. The cooperation of mean shift and Kalman filter algorithm estimating of moving objects' approximate location could achieve the stable and continuous tracking in the condition of multi-objects with scatter and gathering with corresponding monitoring precision of 96% and 93%. The real-time tracking experiment of the adults moving trace in pest monitoring zones by the aid of machine vision further validated the practicability of the Hendel adults population density monitoring for providing a theoretical and practical basis for in-field Hendel adults automatic monitoring technology studies.
Number of references:32
Main heading:Condition monitoring
Controlled terms:Algorithms - Computer vision - Experiments - Kalman filters - Monitoring - Orchards - Pest control - Population statistics
Uncontrolled terms:Automatic monitoring - Bactrocera Dorsalis (Hendel) - Development of science and technologies - Kalman filter algorithms - Linear minimum variance - Machine vision technologies - Mean shift - Population densities
Classification code:603 Machine Tools - 706 Electric Transmission and Distribution - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 731.1 Control Systems - 803 Chemical Agents and Basic Industrial Chemicals - 821.3 Agricultural Methods - 901.3 Engineering Research - 921 Mathematics - 922.2 Mathematical Statistics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.026
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 4>

Accession number:201436062562
Title:Biogas-producing characteristics of anaerobic digestion of protected horticulture residues
Authors:Luo, Juan (1); Tian, Yishui (1); Chen, Ling (1); Song, Chengjun (1); Qi, Yue (1); Li, Xiaogang (1); Zhao, Lixin (1)
Author affiliation:(1) Chinese Academy of Agricultural Engineering, Key Laboratory of Energy Resource Utilization from Agricultural Residues, Beijing, China
Corresponding author:Zhao, Lixin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:256-263
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:With the large-scale popularization of protected horticulture, many protected horticulture residues, which include vegetable stalks and fruit scrap, followed in recent years; and it is imperative to adopt a method of properly handling the residues. Protected horticulture residues have characteristics of high water content, high volatile solids content, and high biodegradability. If the residues are treated simply as general living garbage, it will lead to not only high costs but also a waste of resources. There are many studies abroad using anaerobic digestion processes to dealing with protected horticulture residues, while the domestic relevant reports are fewer. To obtain more detailed data about the biogas production characteristics of typical protected horticulture residues, and to explore the possibility of the application of Separated two phase anaerobic digestion (STP), in this study, five typical different protected horticulture residues are chosen as research subjects. The characteristics of five typical different protected horticulture residues-cucumber vine, tomato stem and leaves, pakchoi, watermelon vine, and grass are analyzed in this paper. Under a warm fermentation condition (38), the biogas production characteristics of these five raw materials are tested. In the condition of 38, watermelon vine, which has the best gas production performance, is chosen to test its adaptability of Separated two phase anaerobic digestion (STP), the biogas production characteristics of watermelon vine under two different reflux modes of spray and immersion is comparatively analyzed, and the main emphasis is on the pH variation of of leachate, biogas production, and methane concentration under two different reflux modes. All of these studies afford useful reference for the resource utilization of protected horticulture residues. The results show that the five protected horticulture residues have the same gas production tendency, reach a peak of gas production in the 3~4 days, and then the gas production declines and persists at a high level. Twenty days later, the gas production is low and stable; after 42 days, almost no gas is generated. These five protected horticulture residues have good gas production of anaerobic fermentation characteristics under warm temperature conditions, and all of them could be a good source for biogas fermentation. The sequence of the biogas potential in the five protected horticulture residues in watermelon vine, pakchoi, cucumber vine, tomato stem and leaves, and grass, and their unit dry mass gas production is 508.85, 458.93, 442.41, 410.17, and375.03 mL/g. Protected horticulture residues have good adaptability to Separated two phase anaerobic digestion (STP), which is shown as higher biogas production and higher methane concentrations. The spray mode of leachate is better suited than the immersion mode, and it has more biogas and higher methane concentrations. The total biogas production of the spray mode is 506.39L and its unit dry mass gas production is 481.21 L/kg, which is 10.81 percent higher than the immersion mode, and its methane concentration is basically stable between 53-56 percent, which was 6-12 percent higher than the immersion mode. In addition, the spray mode is generally more suitable for STP because of its greater stability.
Number of references:30
Main heading:Agriculture
Controlled terms:Agricultural wastes - Anaerobic digestion - Biodegradation - Biogas - Fermentation - Fruits - Methanation - Separation
Uncontrolled terms:Anaerobic digestion process - Anaerobic fermentation - Fermentation conditions - High-volatile solids - Methane concentrations - Protected horticulture residues - Resource utilizations - Two phase anaerobic digestion
Classification code:801.2 Biochemistry - 802.2 Chemical Reactions - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2014.15.033
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 5>

Accession number:201436062561
Title:Response of climate changes on vegetation cover in north of Tianshan Mountains evaluated using multiple time scales
Authors:Sun, Qinming (1); Liu, Tong (1); Han, Zhiquan (2); Liu, Huafeng (1); Dong, Hegan (1); Qin, Chunming (3)
Author affiliation:(1) College of Life Science, Shihezi University, Shihezi, China; (2) Teachers College, Shihezi University, Shihezi, China; (3) Teorological Bureau of Shihezi, Shihezi, China
Corresponding author:Liu, Tong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:248-255
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Climate is related with vegetation on regional and even global scales, and climate affects spatial distribution of vegetation. Studies on correlation between NDVI and changes in climate using different time scales and different regional condition are helpful to reveal the effects of climate changes on vegetation. This study investigated the characteristics of vegetation change and its response to precipitation and temperature change during the 29 years (1981-2009) in the north of Tianshan Mountains in Xinjiang Province by the method of wavelet cross-correlation technique combined with trend analysis. The explored study area included Irtysh River, Bortala Valley, Ili River Valley, the northern slope of the Tianshan Mountains and the western Junggar Basin. These regions are far from the sea and surrounded on three sides by the Tianshan Mountains, Tarbagatai Mountains, and Altai Mountains, creating a special climate system which was an ideal environment for the study of regional climate-vegetation interactions. The daily meteorological data from January 1, 1981 to December 31, 2009 were collected from NOAA/AVHRR NDVI digital images (1981-2001) and SPOT-4 VEGETATION NDVI digital images (1998-2010). The results showed that in the northern Tianshan Mountains, temperature and precipitation change had similar tendencies except for the northern slopes of the Tianshan Mountains and in the Junggar Basin. The increase in the humid index decreased from the southwest to the northeast. Temperature increase may be primarily responsible for regional drying, while precipitation changes directly affected regional dryness and wetness. The annual mean NDVI distinctly differed among the six regions and it increased in the Bortala Valley, Ili River, Junggar Basin, and the mountains west of the Junggar Basin. The annual maximum NDVI decreased in all the regions except for the Junggar Basin. The correlation between early changes in climate and subsequent vegetation had multiple-time-scale characteristics, and all the regions showed similar overall correlations on different time scales. Time lag was another characteristic affecting the process above. The suitable time scale and time lag reflecting the response of vegetation to precipitation change was 15 ten-day periods and 5 ten-day periods except for the western Junggar Basin where time lag was 2 ten-day periods. The useful time scale and time lag reflecting the response of vegetation to temperature was 15 ten-day periods except the western Junggar Basin where the time scale was 10 ten-day periods and 2 ten-day periods, respectively. The correlation between NDVI change and early changes in temperature (0.587) was higher than that between NDVI and early changes in precipitation (0.456). The response of vegetation to climate change suggested that the effects of climate change on vegetation could differ greatly with time lags. This study could provide theoretical support for vegetation coverage monitoring, and enrich the knowledge about the complex climate-vegetation relationships.
Number of references:33
Main heading:Landforms
Controlled terms:Climate change - Correlation methods - Ecosystems - Meteorology - Sump pumps - Temperature - Time measurement - Vegetation
Uncontrolled terms:Normalized difference vegetation index - Northern tianshan mountains - Time lag - Vegetation cover - Wavelet cross-correlation
Classification code:443 Meteorology - 451 Air Pollution - 454.3 Ecology and Ecosystems - 481.1 Geology - 618.2 Pumps - 641.1 Thermodynamics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 922.2 Mathematical Statistics - 943.3 Special Purpose Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.032
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 6>

Accession number:201436062565
Title:Comparison of rural residential renovation based on Lewis turning point and ecological connectivity
Authors:Zhou, Hua (1); Lu, Chunfeng (1); Chang, Ting (1); Wu, Wei (1)
Author affiliation:(1) School of Geographic and Oceanographic Sciences, Nanjing University, Nanjing, China
Corresponding author:Zhou, Hua
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:281-288
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There are more than 60% people living in rural area even though the urbanization of China is over 50%. That means many people move between rural and urban area, which are called peasant-worker. And this semi-urbanization phenomenon leads to rural people can not migrate to urban completely, and the rural residential area expands inevitably. Also because of the population growth and the resource consumption, it also puts pressure on the rural ecosystem. Rural residential renovation needs to preserve adequate rural population and at the same time to consider the influence for ecological patterns. Rugao county is one of the highest rural residence per unit area, and one of fastest urbanization areas in Jiangsu province. In recent years, the government takes Rugao as the rural reform pilot area, and put many rural residential renovation projects in this area aiming to solve the rural residence expansion and ecological problems. This paper took Million Hectares of Fertile Farmland Project of Chaiwan town, Rugao county as a case study. The main processing software included ArcGIS9.3 and Matlab, and GIS spatial analysis method was used for ecological resilience analysis. We used natural villages as an independent unit and ran the best ecological renovated model based on the Lewis turning point and ecological connectivity by minimal cumulative resistance model. The findings showed that rural population could not migrate to urban completely and urbanization had a certain limit based on the consideration of the necessity of agriculture production and the influence of other income sources. It showed that rural residence should be maintained at a reasonable scale, rural population flow and rural residential renovation should be taken as reasonable goals in the urbanization. As an intelligent algorithm, the genetic algorithm in the model had capability in intelligent decision support. It can take results quickly through the crossover, heredity and variation operator. The results of studied area showed that there were at least 53 results by genetic algorithm. The schemes can be applied in study area that was not unique. The urbanization can be achieved between 77.96%-78.63%, which preserved 21.37%-22.04% population in rural area for agriculture production, and this was consistent with international experience. Different patterns of rural residential renovation schemes can have different ecological influence, and different sizes of isolated ecological islands, and the island sizes can be different more than 2.29 times despite the similar urbanization rate. The paper suggested to take the lower influencing scheme under the suitable urbanization, and to take certain policy recommendations in order to implement rural residential renovation smoothly.
Number of references:26
Main heading:Ecology
Controlled terms:Agriculture - Decision support systems - Genetic algorithms - Geographic information systems - Housing - Land use - Population statistics - Rural areas
Uncontrolled terms:Agriculture productions - Ecological connectivities - Intelligent decision support - International experiences - Rural residential - Rural residential areas - Rurgao county - Turning points
Classification code:403 Urban and Regional Planning and Development - 403.1 Urban Planning and Development - 454.3 Ecology and Ecosystems - 723 Computer Software, Data Handling and Applications - 723.3 Database Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 922.2 Mathematical Statistics
DOI:10.3969/j.issn.1002-6819.2014.15.036
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 7>

Accession number:201436062566
Title:Model analytical and verification of heat and moisture characteristics in litchi drying
Authors:Li, Changyou (1); Zhao, Yikun (1); Ma, Xingzao (1)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou, China
Corresponding author:Li, Changyou
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:289-298
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The dynamic characteristics of temperature and moisture distribution within litchi, which is the key influence on drying quality formation and energy-consumption, is the important technical foundation problem for litchi postpartum processing. In order to reveal the dynamic characteristics of temperature and moisture distribution within litchi in unsteady drying process, guide the drying process design, improve the drying quality, and reduce drying energy, based on the diffusion model, the characteristic parameter of litchi is studied. Meanwhile, the drying characteristics representation of litchi is investigated on the basis of the drying characteristics test on litchi peel, pulp, and kernel. When the relative humidity is 10 percent and temperatures range from 35 to 50, the drying constant and dry basis equilibrium moisture content is researched, and the results are 0.5965 h^-1-0.6717 h^-1 and 7.55 percent -60.92 percent, respectively. While the relative humidity is 60 percent, and the temperature is 40 and 50, the researchers have determined that the drying constant is 0.076 h^-1 and 0.098 h^-1, respectively, and that the dry basis equilibrium moisture contents is 211.35 percent and 141.06 percent, respectively. The results show that the drying conditions have great influence on the drying characteristic parameters of litchi. The water vapor pressure inside litchi exists at an extreme value point during litchi drying, and after that, the drying process is closed to isothermal processes. At the beginning of litchi drying (within 20 min), the internal temperature difference of litchi is the greatest. The thermal conductivity coefficients of peel, pulp, and kernel have some differences, but in the same drying time, they have less effect on the internal temperature distribution of litchi. By using the Lars transformation, the heat conductivity and thermal balance equations are solved simultaneously, and the internal temperature, water vapor partial pressure distribution and its analytic formula of variation law of litchi are achieved. The validation test is investigated when the drying medium temperature is 50 , the relative humidity is 10 percent, the litchi initial temperature is 10 , and the dry basis moisture content is 388 percent. The results show that the measured values of the internal temperature change of litchi is consistent with the analytical values, which confirm the reliability of the analytical model. The research results are of great significance for providing reference to reveal the drying quality mechanism of litchi, enriching analytical theory of the litchi drying thermal and mass transfer, as well as improving the drying quality of litchi, guiding drying design, achieving high efficiency, and saving energy.
Number of references:33
Main heading:Drying
Controlled terms:Food technology - Models - Moisture - Moisture determination - Moisture meters - Temperature - Thermal conductivity - Water vapor
Uncontrolled terms:Analytical method - Drying characteristics - Dynamic characteristics - Equilibrium moisture contents - Internal temperature distribution - Litchi - Moisture distribution - Thermal conductivity coefficient
Classification code:641 Heat and Mass Transfer; Thermodynamics - 641.1 Thermodynamics - 642.1 Process Heating - 801.4 Physical Chemistry - 822 Food Technology - 902.1 Engineering Graphics - 944.1 Moisture Measuring Instruments - 944.2 Moisture Measurements
DOI:10.3969/j.issn.1002-6819.2014.15.037
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 8>

Accession number:201436062548
Title:Effect of phosphorus application in different soil depths on root distribution and grain yield of winter wheat under different water conditions
Authors:Kang, Liyun (1); Shen, Yufang (1); Yue, Shanchao (1); Li, Shiqing (1)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Northwest A and F University, Yangling, China; (2) College of Forestry, Northwest A and F University, Yangling, China
Corresponding author:Li, Shiqing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:140-147
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to find out the best water-phosphorus (P) application method in improving grain yield and water use efficiency of winter wheat grown on the semi-arid Loess Plateau of China, this study evaluated the effects of phosphorus application at different soil depths on root length distribution, water use efficiency and grain yield of winter wheat under different water condition and analyzed the relationship between root distribution and grain yield. The experiment consisted of four P treatments and two water treatments in a randomized complete block design with three replicates. The four phosphorus levels included no P (CK), surface P (SP), deep P (DP) and deep band P (DBP) and the two water treatments were irrigation (W1) and no irrigation (W2) in the whole growth period of winter wheat. The results showed that there was large difference in root length distribution, water use efficiency and grain yield of winter wheat among different treatments. Compared with the irrigation treatment, the non-irrigation treatment significantly (P&lt;0.05) lowered the surface soil root length (0-30 cm) by 17.5%, but significantly increased (P&lt;0.05) deep soil root length (30-100 cm) by 13.3%, which would be helpful in promoting the absorption of soil water and P, water use efficiency and grain yield. Root length density was increased at the site of placement where P was applied under the two water treatments, particularly under water stress. Whether irrigation or not, P application (SP, DP and DBP) caused the increase of P uptake amount, water use efficiency and grain yield, compared with the CK treatment. The effect of P placement on water use efficiency and grain yield of winter wheat was different. Deep P application (DP and DBP) significantly (P&lt;0.05) decreased water use efficiency of winter wheat compared with SP by 13.3%, while significantly (P&lt;0.05) increased water use efficiency and grain yield under non-irrigation treatment by 28.5% and 16.0%, respectively. Furthermore, root length in deep soil layer (30-100 cm) was positively correlated with P uptake amount, grain yield and water use efficiency under non-irrigation condition,that is, the longer deep soil root length, the better water use efficiency and higher production under soil drought condition. No correlation was found between root length in deep soil layer (30-100 cm) and P uptake amount, grain yield and water use efficiency under irrigation condition, highlighting the importance of well-developed subsoil root system for both high grain yield and water use efficiency. The study suggested that deep placement of fertilizer phosphorus was a practical and feasible method of increasing grain yield and water use efficiency under water stress conditions by promoting deep root development.
Number of references:35
Main heading:Efficiency
Controlled terms:Crops - Fertilizers - Forestry - Irrigation - Moisture - Phosphorus - Plants (botany) - Soil moisture
Uncontrolled terms:Different soils - Different treatments - Irrigation treatments - Loess plateau of chinas - Phosphorus applications - Root length - Water use efficiency - Yield
Classification code:461.9 Biology - 483.1 Soils and Soil Mechanics - 801.4 Physical Chemistry - 804 Chemical Products Generally - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2014.15.019
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 9>

Accession number:201436062540
Title:Effect of fuel temperature and injection pressure on spray characteristics of sunflower oil and diesel
Authors:He, Xu (1); Liu, Hai (1); Zeng, Weilin (1); Yu, Hongdong (2); Bohl, Thomas (2); Tian, Guohong (2); Li, Xiangrong (1); Liu, Fushui (1)
Author affiliation:(1) School of Mechanical Engineering, Beijing Institute of Technology, Beijing, China; (2) Sir Joseph Swan Centre for Energy Research, Newcastle University, Newcastle, United Kingdom
Corresponding author:Li, Xiangrong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:75-82
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To study the fuel atomization problem when raw vegetable oil is used as an alternative fuel of compression-ignition internal combustion engine, this paper investigated the differences in spray characteristics between raw sunflower oil and regular diesel under different experimental conditions using the Schlieren method. The focus of this study is the effects of fuel temperature and injection pressure on the spray penetration distance, the spray cone angle, and the air entrainment of fuels injected into the constant volume vessel. The results show that both the spray penetration distance and the spray cone angle of the sunflower oil increase with increasing the fuel injection pressure and fuel temperature, which are similar to those of regular diesel. When the fuel temperature is increased from 60 to 90, the average increases in the spray penetration distance and cone angle of the sunflower oil are 12.4% and 9.6%, respectively, at 60 MPa injection pressure. Such increases are 5% and 4.14% respectively at 120 MPa injection pressure. When the injection pressure is increased from 60 MPa to 120 MPa, the percentage increases in the mean spray penetration distance and cone angle are 39.7% and 16.7% respectively at the fuel temperature of 60 and 30.6% and 10.9% respectively at 90. When the injection pressure, background pressure, and fuel temperature are the same, the sunflower oil spray has a greater penetration distance but a smaller spray angle than that of diesel. The average increase of the spray penetration of the sunflower oil is 22.5% and the average decrease of spay cone angle is 60.3%. Elevating the fuel temperature or increasing the fuel injecting pressure can enhance the entrainment of air into the spray; However, the air entrainment of the sunflower oil spray is significantly weaker than that in the ordinary diesel spray. The results provide a valuable reference on the spray characteristics to help evaluate the feasibility of using raw vegetable oil as an alternative fuel for internal combustion engines.
Number of references:25
Main heading:Air entrainment
Controlled terms:Alternative fuels - Biofuels - Diesel fuels - Fuel injection - Internal combustion engines - Schlieren systems - Sunflower oil - Vegetable oils
Uncontrolled terms:Background pressure - Constant-volume vessel - Experimental conditions - Fuel atomization - Injection pressures - Schlieren method - Spray characteristics - Spray penetration
Classification code:521 Fuel Combustion and Flame Research - 523 Liquid Fuels - 524 Solid Fuels - 612.1 Internal Combustion Engines, General - 742.2 Photographic Equipment - 802.3 Chemical Operations - 804.1 Organic Compounds
DOI:10.3969/j.issn.1002-6819.2014.15.011
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 10>

Accession number:201436062539
Title:Analysis of porosity structure of particles from diesel engine using small angle X-ray scattering
Authors:Zhao, Yang (1); Wang, Zhong (1); Li, Ruina (1); Li, Mingdi (1); Wang, Xiangli (1)
Author affiliation:(1) School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang, China
Corresponding author:Zhao, Yang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:68-74
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Particles which contain soluble organic fraction (SOF), soot, and inorganic salt are mainly the result from an incomplete combustion or pyrolysis of fossil fuels and other organic materials. In a diesel engine, the poor mixing of fuel and air creates fuel-rich zones that support particle formation at high temperatures. Numerous studies show that they are harmful to human health when inhaled and may cause cancer. For that reason, it is important to reduce the formation or at least the emission of particles to the environment. Meanwhile, the strict regulations for particulate matter emission have been enforced in many developed countries. A diesel particulate filter (DPF) is currently the dominant diesel particulate emissions control technology to meet stringent air quality standards, however, the oxidation ability of particles is important to the regeneration of the filter bed in DPF. Temperature has a great influence on the oxidation process of particles. Many physical and chemical changes of particles happen at a high temperature, leading to porosity formation of particles during oxidation. The porosity structure of particles is important to the oxidation ability of particles. The micro-orifice uniform deposition impactor (MOUDI) is a favorable apparatus for obtaining the particle size distribution and collecting the particles in different size ranges after classification. Thermogravimetric analysis (TGA) has been widely used as an analytical method for investigating the relationship between the material weight and temperature under the condition of programming a temperature rise. The curve of the sample weight then can be obtained with the temperature. A derivative thermal gravimetry (DTG) curve, the first order differential to a TG curve, can reveal the features of mass variation with the temperature. Small-angle X-ray scattering (SAXS) is a widely used diffraction method for studying the structure of the sample. In this study, the micro-orifice uniform deposit impactor was used to collect particle samples; the thermal gravimetric analysis was used to investigate the ignition of particles as a basis for determining the oxidation temperature; and the change rules of porosity structure parameters, porosity quantities, and size distribution of particles in the oxidation process were investigated by synchrotron (SAXS). The results of the thermogravimetric analysis showed that the ignition temperature of diesel particles was 487, and the oxidation temperature range should be set up under 400 for study on the porosity structure of particles during oxidation. The results of small-angle X-ray scattering showed that the electron density difference of combustion particles increased, and the size of particles reduced the fractal dimension, average radius, gyration radius, and axial length all significantly increased as the oxidation temperature increased. The tightness of the porosity structure decreased, and the number and size of porosity all increased with increasing oxidation temperature. The porosity size of particles at 100 was mainly distributed in a range of 6-7 nm. The porosity size of particles at 200 was mainly distributed in a range of 8-9nm. The porosity size of particles at 400 was mainly distributed in a range of 12-13 nm.The study provided valuable information on mechanisms of particle oxidation.
Number of references:30
Main heading:Porosity
Controlled terms:Agricultural machinery - Combustion - Diesel engines - Elementary particles - Fractal dimension - Oxidation - Oxidation resistance - Particle size analysis - Particles (particulate matter) - Thermogravimetric analysis  - X ray scattering
Uncontrolled terms:Diesel particulate filters - Distribution of particles - First-order differentials - Micro-orifice uniform deposit impactor - Particulate matter emissions - Small angle X-ray scattering - Soluble organic fraction - Thermal gravimetric analysis
Classification code:521.1 Fuel Combustion - 612.2 Diesel Engines - 801 Chemistry - 802.2 Chemical Reactions - 804 Chemical Products Generally - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids - 931.3 Atomic and Molecular Physics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.15.010
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 11>

Accession number:201436062549
Title:Experiment on water use efficiency and yield of different plant type of potted maize under negative pressure water control
Authors:Xu, Gaoping (1); Wang, Pu (1); Xue, Xuzhang (2); Zhang, Fang (2); Chen, Fei (2)
Author affiliation:(1) College of Agriculture and Biotechnology, China Agricultural University, Beijing, China; (2) National Research Center for Intelligent Agricultural Equipment, Beijing, China
Corresponding author:Xue, Xuzhang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:148-156
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Drought can lead to yield reduction and is the predominant threat to maize production in China. This study compared responses of different plant types (small plant type CF1002 and large plant type CF3330) to drought stress in a pot experiment of soil water deficit. Three soil moisture treatment included no-stress (CK), mild and severe drought stress. A negative pressure water supply device was used for accurate water supply so as to minimize effect of variation in soil moisture on plant growth and yield. Water use efficiency (WUE), aboveground dry matter, leaf area, and yield and its components of maize were determined. Water consumption at the seedling and silking stages of maize, photosynthetic rate and transpiration rate at filling stage was calculated. The results showed that the WUE of CF1002 increased from 3.24 to 3.43 with increasing drought stress intensity at the seedling stage. In comparison, the WUE for CF3330 decreased from 3.70 to 3.25 under mild and severe drought stress at the seedling stage. Compared with the CK, the WUE of CF1002 and CF3330 was decreased by 2.7% and 24.4% under mild drought stress at the silking stage, and by 17.4% and 57.1% under severe drought stress at the silking stage. The mild and severe drought stress during silking stage decreased the water consumption of CF1002 and CF3330 by 61.3% and 62.5%, the photosynthetic rate of CF1002 and CF3330 by 22.9% and 54.3%, and the aboveground dry matter of CF1002 and CF3330 by 24.8% and 38.0%, thereby resulting in yield reduction by 47.9% and 71.5%, respectively. The decline of water consumption, photosynthetic rate, aboveground dry matter, and yield in CF3330 was higher than that in CF1002. The results above indicated that maize with large plant type (CF3330) was more sensitive to drought stress at the middle-late growth stage such as the silking stage than that of the small plant type. Photosynthesis and transpiration of CF3330 were susceptible to mild and severe drought stress, especially at the silking stage, leading to the reduction of aboveground dry matter production and accumulation as well as water consumption. The difference of CF1002 and CF3330in response of water consumption, yield and water use efficiency to drought stress at the early and late growth stage suggested the necessity of maize cultivation based on plant type. Therefore, optimal water management strategy based on plant type should be applied in the late growth stage after silking in order to reduce damage caused by drought stress.
Number of references:31
Main heading:Water supply
Controlled terms:Crops - Drought - Efficiency - Experiments - Grain (agricultural product) - Plants (botany) - Soil moisture - Transpiration - Water management
Uncontrolled terms:Dry matter production - Maize (Zea mays L.) - Photosynthetic rate - Plant types - Transpiration rates - Water consumption - Water management strategies - Water use efficiency
Classification code:444 Water Resources - 446 Waterworks - 446.1 Water Supply Systems - 461.9 Biology - 483.1 Soils and Soil Mechanics - 821.4 Agricultural Products - 901.3 Engineering Research - 913.1 Production Engineering
DOI:10.3969/j.issn.1002-6819.2014.15.020
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 12>

Accession number:201436062537
Title:Anti-corrosion properties of Ni-P alloy coated on engine cylinder prepared from jet electrodeposion
Authors:Wang, Ying (1); Kang, Min (1); Fu, Xiuqing (1); Wang, Xingshen (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing, China; (2) Jiangsu Key Laboratory for Intelligent Agricultural Equipment, Nanjing, China
Corresponding author:Kang, Min
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:54-61
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cylinder is the important part of tractor engine, which service life and the production cost are directly affected by anti-corrosion of the component. With the excellent wear resistance, corrosion resistance and higher hardness, Ni-P alloy deposited layer plays an important role for enhance the service life and reliability of cylinder, and the capability and quality of the tractor engine can be improved. Because of severe working environment of cylinder and piston such as high temperature, high load, high-velocity motion, poor lubrication, difficult cooling, especially weak acid for work environment, it is advisable to study the anti-corrosion properties of Ni-P alloy coated on engine cylinder. However, with the advancement of social economy, the conventional method for electrodeposited Ni-P alloy fails to meet the requirements of the development due to lower depositing rate and lower production efficiency. The jet electrodeposition is developed in recent years, which can significant increase the production efficiency because jet electrolyte can accelerate transfer process of the electrodeposition material and augment limiting current density. So the jet electrodeposition is a kind of high-velocity, selective electrodeposition technique with high deposition current density. In this paper, the engine cylinder coated with Ni-P alloy with jet electrodeposition was taken as research object. The surface appearance of deposited layer was observed by 6XB-PC reflective optical microscope. The corrosion behavior of Ni-P alloy coated on cylinder in 50 g/L NaCl solutions at different moment was studied by electrochemical impedance spectroscopy and potentiodynamic polarization method. The results show that the coating surface appearance is dense and smooth. Electrochemical impedance spectroscopy is composed of high and low frequency arcs when the layer immersed in 50 g/L NaCl solutions with 0.5, 1, 6, 12 and 24 h. The high frequency arcs have relation with original oxidation film, and the low frequency arcs have relation with corrosion process of electrode. While the layer is immersed in 50 g/L NaCl solutions 48 and 72 h, the electrochemical impedance spectroscopy is composed of high, medium and low frequency capacitive reactance arcs. The corrosion resistance of Ni-P alloy coating has the trend of decrease and then increase with the immersion time duration. At first, the thickness of oxide layer is thinned in 50 g/L NaCl solutions due to the attack of Cl^-. After oxide layer by Cl^- penetration, Ni-P alloy will begin to dissolve. And then, the corrosion products are generated and gather on Ni-P alloy, which prevent the process of corrosion. The whole corrosion processes changed from activation control into diffusion control of Ni-P alloy coating and corrosion products. The corrosion resistance of Ni-P coating obtained by jet electrodeposition is about 5 times to traditional electrodeposition. Obviously, Ni-P alloy coating prepared from jet electrodeposition has excellent corrosion resistance. The study can provide a reference for improving the anti-corrosion properties of Ni-P alloy coated on engine cylinder with jet electrodeposion.
Number of references:28
Main heading:Jet engines
Controlled terms:Alloys - Coatings - Corrosion protection - Corrosion resistance - Electrochemical impedance spectroscopy - Electrodeposition - Engine cylinders - Engines - Metal cladding - Nickel  - Tractors (truck)
Uncontrolled terms:Anti-corrosion property - Deposition current density - Excellent corrosion resistances - Jet electrodeposition - Limiting current density - Polarization curves - Production efficiency - Selective electrodeposition
Classification code:531.1 Metallurgy - 538.2 Welding - 539 Metals Corrosion and Protection; Metal Plating - 548.1 Nickel - 612 Engines - 612.1.1 Internal Combustion Engine Components - 653.1 Aircraft Engines, General - 663.1 Heavy Duty Motor Vehicles - 801 Chemistry
DOI:10.3969/j.issn.1002-6819.2014.15.008
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 13>

Accession number:201436062569
Title:Process of yogurt by nanofiltration concentration from raw milk
Authors:Wang, Yutang (1); Guo, Wenkui (1); Chi, Tao (2); Cheng, Tao (1)
Author affiliation:(1) College of Food Science, Key Laboratory of Dairy Science, Northeast Agricultural University, Harbin, China; (2) National Dairy Engineering and Technical Research Center, Harbin, China
Corresponding author:Cheng, Tao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:317-324
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, yogurt products are usually developed and designed by using different raw materials and food additives, less by innovations of production processes. For the development of new technology for producing yogurt, considering the technical feasibility of nanofiltration concentration's application in yogurt production process, the paper put forward an idea for developing new yogurt products by improving the workmanship. In this study, the raw milk was concentrated by nanofiltration membrane when producing yogurt with transmembrane pressure of 1.0, 1.6, 2.0, 2.4 MPa and the milk temperature of 10, 15, 55, 65, respectively, in order to investigate the change of milk composition during concentration and its influence on yogurt texture and rheological parameters, as while as the influence of raw milk on nanofiltration membrane performance at different temperatures and pressures. The results indicate that, under the conditions of 65 and 2.0 MPa, the concentration was feasible and it can be applied in yogurt production when the membrane flux is 7.5 L/(m²&middot;h) and concentration time is about 85 min. The retention rates of monovalent ions of sodium, potassium, chlorine are 40.8%, 46.5% and 17.8%, respectively, while the divalent ions of calcium and magnesium are 94.2%, 95.7%, respectively, and the other milk contents, the lactose and protein, are 92.4% and 95.7%, respectively. The non-fat dry matter increases by 1.24 times, the fat increases by 1.3 times and the milk acidity increases by 1 degree. The viscosity of yogurt producing through concentration is 27.8 Pa&middot;s, and which of yogurt without concentration is 16 Pa&middot;s. With the texture profile analysis (TPA) on yogurt texture, the hardness, adhesiveness, gumminess and chewiness of yogurt with concentration is 0.4605 N, -0.6492 N&middot;s, 0.3253 N&middot;s and 0.2987 N&middot;s, respectively, while the indexes of yogurt without concentration is -0.1102 N, -0.4787 N&middot;s, 0.0680 N&middot;s and -0.0586 N&middot;s, respectively. These texture and rheological parameters of the yogurt with concentration are all superior to those of the yogurt without concentration technology.
Number of references:29
Main heading:Dairy products
Controlled terms:Concentration (process) - Nanofiltration - Nanofiltration membranes - Process design - Textures
Uncontrolled terms:Calcium and magnesiums - Concentration-time - Cow milk - Production process - Rheological parameter - Texture profile analysis - Transmembrane pressures - Yogurt
Classification code:802.1 Chemical Plants and Equipment - 802.3 Chemical Operations - 822.3 Food Products - 913.1 Production Engineering - 933 Solid State Physics - 933.1 Crystalline Solids
DOI:10.3969/j.issn.1002-6819.2014.15.040
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 14>

Accession number:201436062544
Title:Internal flow characteristics analysis on S-shaped region of reversible pump-turbine
Authors:Li, Jun (1); Wang, Lei (1); Liao, Weili (3)
Author affiliation:(1) Institute of Electric Power, North China University of Water Resources and Electric Power, Zhengzhou, China; (2) State Grid Henan Baoquan Pumped Storage Company Limited, Xinxiang, China; (3) Institute of Water Resources and Hydro-electric Engineering, Xi'an University of Technology, Xi'an, China
Corresponding author:Li, Jun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:106-113
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Pumped storage power station plays a more and more important role in modern society. And it is the important index to judge the national energy usage efficiency and clean energy usage. At present, the development of reversible pump turbine shows several significant features, such as high head, large capacity, high speed and so on. But there exist some problems on design, manufacture and operation of the unit. The S-shaped region of complete characteristics curve on reversible pump-turbine used in the pumped storage power station brings great challenges to the stable operation of the unit, such as low success rate when starting, difficult for mode transformation and grid-connected, as a result, it will seriously influence the operation of the pumped storage power station. So, many researchers focus studies on the problem. In this paper, the study object was the 1^# pump-turbine in Baoquan storage power station. According to the contrast between experimental value and calculation of "S" curves, the calculation of CFD can reflect the basic characteristics of the unit "S" characteristics actually. With the numerical calculations of 4 modes under the condition of 2 guide vane opening, the streamline distribution was analyzed in spiral case and fixed guide vane, in guide vane and runner, and in draft tube. Some literatures and actual operations of unit showed that, the "S" characteristics appeared easily under the condition of low-head turbine mode, and it would be improved with head increase. In order to explore the reasons, with the numerical calculations of runaway mode under the condition of 10 guide vane opening, the relationship between the water head variation and "S" character was analyzed comparatively. The trend and variation rule of internal flow was grasped essentially. It pointed out that the important reason for the formulation of "S" characteristics was channel congestion caused by cortex. At the same time, it showed that the effects on unit of "S" characteristics could be eliminated or reduced through the late intervention and improvement of hydraulic design. The former core was to try to avoid S-shaped region. This method was to enlarge discharge by misaligned guide vane apparatus (MGV) and has been used in Tianhuangping pumped storage power station. But it increased the difficult of unit control and workload, and the breakdown of MGV apparatus would reduce the success rate of unit's starting, and also it would cause the flow complex in the runner. So it is a remedial countermeasure. The later method was to eliminate the S-shaped region through the change of flow regime at the period of hydraulic design and model test. Taking account of two modes, now it is difficult to select pump-turbine, and it is the study emphases in the future. The research findings of this paper can provide a technical support for unit stable operation and further study of "S" characteristics.
Number of references:28
Main heading:Hydraulic turbines
Controlled terms:Computer simulation - Models - Pumped storage power plants - Turbine pumps - Turbulence - Water piping systems
Uncontrolled terms:Basic characteristics - Internal flow characteristics - Mode transformation - Numerical calculation - Pumped storage power station - Reversible pump-turbine - S characteristics - Streamline distributions
Classification code:402.1 Industrial and Agricultural Buildings - 443.1 Atmospheric Properties - 446.1 Water Supply Systems - 617.1 Hydraulic Turbines - 618.2 Pumps - 723.5 Computer Applications - 902.1 Engineering Graphics
DOI:10.3969/j.issn.1002-6819.2014.15.015
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 15>

Accession number:201436062568
Title:Effects of refrigerated truck temperature field uniformity on preservation of vegetables
Authors:Zhang, Zhe (1); Li, Limin (1); Tian, Jinjin (1); Guo, Yonggang (1); Li, Man (1)
Author affiliation:(1) Tianjin Key Laboratory of Refrigeration Technology, Tianjin University of Commerce, Tianjin, China
Corresponding author:Zhang, Zhe
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:309-316
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Therefore, the experimental system for a refrigerated truck and data acquisition system has been developed. The experimental system consists of the refrigeration system, carriage of the refrigerated truck, and the fan. The data acquisition system includes the acquisition board, acquisition program, personal computer, anemometer, and thermocouples. The temperature in the refrigerated truck can be adjusted by the thermostat based on the different temperature requirements. To assess the temperature distribution in the refrigerated truck, the temperature non-uniformity (S) has been defined. In this paper, three kinds of vegetables (baby cabbages, peppers, and flammulina velutipes) have been tested in the refrigerated truck under different conditions. The weight loss rate, membrane penetration rate, vitamin c content, and chlorophyll content were evaluated under different storage conditions with three kinds of air supply forms. Weight loss rate, membrane penetration rate, and vitamin c content were evaluated under different storage conditions with different temperature fields, with temperature non-uniformity values of S<inf>I</inf>=3.71, S<inf>II</inf>=5.68, and S<inf>III</inf>=8.36. It was found that the effect of the temperature field on the quality of vegetables is significant. Results show that the uniform temperature field has a better effect on preservation. The reason for this is that the more uniform the temperature is distributed, the more uniform the cold energy is distributed. In doing so, vegetables can be kept at the appropriate temperature environment; thus, the quality of vegetables can be kept for a long time. The three kinds of vegetables (baby cabbages, peppers, and flammulina velutipes) show the same result. This study can provide a reference for the optimization design of the refrigerated truck. The results can contribute to improving the quality control of vegetables or agricultural products during the process of refrigerated transport.
Number of references:29
Main heading:Trucks
Controlled terms:Energy storage - Food storage - Fruits - Personal computers - Quality assurance - Quality control - Refrigeration - Temperature distribution - Thermocouples - Vegetables
Uncontrolled terms:Data acquisition system - Fruits and vegetables - Refrigerated transport - Temperature environments - Temperature field distribution - Temperature fluctuation - Uniform temperature field - Uniformity
Classification code:641.1 Thermodynamics - 644.4 Cryogenics - 663.1 Heavy Duty Motor Vehicles - 702 Electric Batteries and Fuel Cells - 722.4 Digital Computers and Systems - 821.4 Agricultural Products - 822.1 Food Products Plants and Equipment - 913.3 Quality Assurance and Control - 944.5 Temperature Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.039
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 16>

Accession number:201436062543
Title:Stress-strain and modal analysis on rotor of marine centrifugal pump based on fluid-structure interaction
Authors:Huang, Haoqin (1); Liu, Houlin (1); Wang, Yong (1); Dai, Hanwei (1); Jiang, Linling (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Corresponding author:Liu, Houlin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:98-105
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In order to analyze the effect of fluid-structure interaction(FSI)on rotor stress-strain and modal in marine centrifugal pump, a 125clla-13 type marine centrifugal pump was chosen as the research object. The unsteady numerical simulations of uncoupling method and two-way coupling method were used in this paper. Based on the result of simulation, the variation of head in the last rotating cycle was compared between the two simulation methods. The later analysis was focused on the effect of one-way coupling method and two-way coupling method on impeller stress and strain under different transient phases, and further modal multi-phase analysis of rotor was conducted based on FSI. The results show that the predicted value of head with two-way coupling method is bigger than the value with uncoupling method under each transient phase, and there is a local fluctuation of predicted value near the peak of head. The maximum deformation of impeller is located at the back shroud and near the middle area of passage outlet. The maximum equivalent stress is at the border of back shroud and low pressure side of blade outlet, and both the values of impeller maximum deformation and maximum equivalent stress based on two-way coupling method are greater than the values based on one-way coupling method under each transient phase. It means that the styles of fluid-structure interaction have a certain affect on the impeller tress-strain. The position and value of impeller maximum deformation and maximum equivalent stress change with the transient phase. When the middle area of impeller passage sweeps across the tongue, a minimal value of maximum deformation appears, and different FSI methods have different effects on the position of impeller maximum deformation. A maximal value of maximum equivalent stress appears when the blade stays near the area of eighth section of volute, and both the maximal difference values of maximum deformation and maximum equivalent stress between the two methods of FSI appears at 6&deg; phase. The maximal difference value of maximum deformation is 0.17&times;10^-5 m, and the maximal difference value of maximum equivalent stress is 0.296 MPa. The difference of FSI methods has little impact on the rotor modal, but both modal frequency and amplitude of the rotor have a fluctuation in a certain range when transient phase changes, while the maximal fluctuation of frequency is 0.9 Hz, the maximal fluctuation of amplitude is 1.62 mm, and both of them are at the fifth order modal. The research results are useful for the vibration reduction design and structure optimization of the marine centrifugal pump.
Number of references:29
Main heading:Modal analysis
Controlled terms:Centrifugal pumps - Deformation - Fluid structure interaction - Impellers - Oceanographic equipment - Structural optimization
Uncontrolled terms:Difference values - Local fluctuations - Multi-phase analysis - Stress and strain - Stress-strain - Structure optimization - Unsteady numerical simulations - Vibration reductions
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 472 Ocean Engineering - 601.2 Machine Components - 618.2 Pumps - 921 Mathematics - 921.5 Optimization Techniques - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.15.014
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 17>

Accession number:201436062550
Title:Influences of combing ridge and no-tillage on rice yield and soil temperature and distribution of aggregate in cold waterlogged field
Authors:Xiong, Yousheng (1); Xu, Xiangyu (1); Zhang, Zhiyi (1); Wang, Juan (1); Yuan, Jiafu (1); Liu, Guangrong (2); Xu, Changxu (2); Mao, Chuangye (3)
Author affiliation:(1) Plant Protection and Soil Fertilizer Institute, Hubei Academy of Agricultural Sciences, Wuhan, China; (2) Institute of Soil and Fertilizer and Resource and Environment, Jiangxi Academy of Agricultural Sciences, Nanchang, China; (3) Agricultural Bureau of Yangxin County in Hubei Province, Huangshi, China
Corresponding author:Xiong, Yousheng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:157-164
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Cold waterlogged paddy field refers to the paddy field submerged under water for extensive period of time in a year. It has the characteristics of "cold in temperature, slush in tillage, rich in plant toxicants, and low in productivity". There are 267 to 400 million hectares of the cold-waterlogged field in China, accounting for 15.07% of the total paddy field area and 44.20% of low-yield paddy field area. Since the waterlogged paddy field has such a large acreage it has become a focus of study in order to make full use of it by increasing rice production. This study aimed to apply ridges and no-tillage together to improve cold spring mud type of cold waterlogged paddy field for rice production in field experiment in 2011 and 2012. Rice was planted by using techniques of conventional till and no till combined with ridging with heights of 10 (LG10), 15 (LG15) and 20 cm (LG20). Soil temperature was monitored throughout the growing season. Rice yields and its component were measured and aggregate distribution was determined from soil samples taken at 0-20 cm depth at the end of the experiment. The results showed that the ridge culture could increase rice yield markedly in cold water-logged paddy field. The rice yield in the LG15 treatment was 10.95% and 18.51% higher (P&lt;0.05) than conventional till in 2011 and 2012, respectively. The ridge culture improved soil temperature of the cold water-logged paddy field as compared to the conventional till. Soil temperature in the LG15 treatment was higher (P&lt;0.05) among different treatments. On an average, soil temperature in ridging treatments was increased by 0.2-1.2 in 0-5 cm soil depth. Different ridge height had effect on the distribution of soil aggregates: large soil aggregates (&gt;1 mm) in the ridging treatments increased greatly in 0-5 cm depth, but highest in LG15 and lowest in conventional till treatment in 5-25 cm. Effect of ridging on soil aggregate distribution on formation of soil aggregate was obvious in 0-5 cm than 5-25 cm. After ridging, the content of large soil aggregate at 0-5 cm soil depth was higher than that at 5-25 cm. However, there was no positive correlation between ridge height and soil temperature and large soil aggregate. In summary, the ridge height under no-tillage of the cold water-logged paddy field was best at 15 cm for rice production.
Number of references:26
Main heading:Soils
Controlled terms:Aggregates - Crops - Cultivation - Temperature
Uncontrolled terms:Cold waterlogged field - No tillage - Rice yield - Ridging - Soil aggregate
Classification code:406 Highway Engineering - 483.1 Soils and Soil Mechanics - 641.1 Thermodynamics - 821.3 Agricultural Methods - 821.4 Agricultural Products
DOI:10.3969/j.issn.1002-6819.2014.15.021
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 18>

Accession number:201436062558
Title:Signal processing method of impact-based grain flow sensor for predicted yield
Authors:Wei, Xinhua (1); Zhang, Jinmin (1); Dan, Zhimin (1); Liu, Chengliang (2)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang, China; (2) School of Mechanical Engineering, Shanghai Jiaotong University, Shanghai, China
Corresponding author:Wei, Xinhua
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:222-228
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Background vibration noise of combine harvester has a significant influence on measuring accuracy of impact-based grain flow sensor. An indoor calibration test bench of impact-based grain flow sensor was developed to study extraction and rejection methods of the background vibration noise from output signal of impact-based grain flow sensor. The test bench was mainly composed of a grain supplying bin, a grain conveying auger, a drag-flight elevator and a grain receiving bin. The auger and the elevator were driven by a three-phase AC asynchronous motor. Grain flow rate was regulated by a spile plate which was mounted at the bottom of the grain supplying bin. Actual grain flow rate was measured with three weight sensors which were mounted between the grain supplying bin and the frame. Revolution speed of the elevator was measured with a revolution speed transducer. Different field working conditions of combine harvester were simulated by adjusting power frequency of the driving motor with a variable frequency generator. A dual-plate differential impact-based grain flow sensor was used in the study which consisted of a measuring plate, a reference plate and 2 strain bridges. The measuring plate accepted impact of the grain flow, and the reference plate sensed background vibration of combine harvester. The measuring plate and the reference plate had a same structure and were parallel mounted to make them have an approximately same mode of vibration. An industrial control system was used to control the variable frequency generator and to acquire output signals of the measuring plate, the reference plate, the weight sensors and the revolution speed transducer. Signal processing was also performed on the industrial control system. Output signals of the measuring plate and the reference plate were acquired synchronously with 3 kHz sampling frequency, and mean filtering was performed to the signals respectively to attenuate random noise. DFT (Discrete Fourier Transformation) was executed to the filtered signals respectively, and the transformed signal of the reference plate was subtracted from the transformed signal of the measuring plate, and IDFT (Inverse Discrete Fourier Transformation) was executed to the differential signal afterwards, thereby frequency-domain differential was fulfilled and yield signal was obtained. Compared with the time-domain differential results the yield signal obtained through the frequency-domain differential method had a less standard deviation. Experiment under different power frequencies of the driving motor showed frequency-domain differential method had a steady effective attenuation effect on background vibration noise rejection for output signal of the dual-plate differential impact-based grain flow sensor. Zero calibration and scale conversion calibration were carried out on the indoor calibration test bench, and yield test experiment under different power frequencies of the driving motor and different actual grain flow rate were performed on the indoor calibration test bench. Yield test experiment results showed the dual-plate differential impact-based grain flow sensor with frequency-domain differential signal processing method had a maximum measuring error of 3.1% with the actual grain flow rate in the range of 0.9 to 2.3 kg/s.
Number of references:24
Main heading:Signal processing
Controlled terms:Augers - Bins - Calibration - Control systems - Design for testability - Discrete Fourier transforms - Elevators - Experiments - Extraction - Flight control systems  - Flow rate - Frequency domain analysis - Grain (agricultural product) - Harvesters - Induction motors - Plates (structural components) - Sensors - Time domain analysis - Traction motors - Transducers  - Vibrations (mechanical)
Uncontrolled terms:AC asynchronous motors - Discrete fourier transformation - Effective attenuation - Frequency domains - Industrial control systems - Noise rejection - Sampling frequencies - Variable frequencies
Classification code:408.2 Structural Members and Shapes - 502.2 Mine and Quarry Equipment - 631 Fluid Flow - 692.2 Elevators - 694.4 Storage - 704 Electric Components and Equipment - 705.3 Electric Motors - 705.3.1 AC Motors - 714.2 Semiconductor Devices and Integrated Circuits - 715 Electronic Equipment, General Purpose and Industrial - 716.1 Information Theory and Signal Processing - 731.1 Control Systems - 801 Chemistry - 802.3 Chemical Operations - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 921.3 Mathematical Transformations - 931.1 Mechanics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.029
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 19>

Accession number:201436062542
Title:Design of sprinkler-drip dual-purpose self-priming pump based on design of experiment
Authors:Li, Hong (1); Yang, Xingbiao (1); Li, Lei (1); Chen, Chao (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Corresponding author:Li, Hong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:93-97
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Agricultural self-priming pump is widely used in sprinkler irrigation and drip irrigation system. But, the self-priming pump that could be used for sprinkler and drip dual-purpose irrigation system is lacking. Common centrifugal pump design method is used for a single point design only and not for multi-objective optimization design. At present, many design methods can be for multi-operation condition. These methods have made a certain progress in solving specific problems, but have some shortcomings such as causing big error between measured and real value. Design of experiment (DOE) is a statistic method for experiment arrangement and data analysis. It has been used for multi-objective optimization design in pump optimization design. The objective of this study was to design a self-priming pump that could be used for sprinkler and drip dual-purpose irrigation system based on DOE and numerical design. As such, the pump was expected to meet with the requirements of two operation conditions, the discharge 12 m³/h and the head 30 m for the sprinkler irrigation and the discharge 18 m³/h and the head 20 m for drip irrigation. The DOE design method was employed in the multi-point design of impeller for the self-priming pumps 50ZB-30C. Numerical simulation was conducted in the environment of computational fluid dynamics (CFX) with speed inlet and free flow outlet. The k-epsilon model was used as turbulence model and the calculation was based on the SIMPLEC algorithm. No slip wall boundary condition was used at the boundary layer. The boundary layer roughness was 25 &mu;m and 0.02 s was chosen for physical time scale. The largest number of iterations was 1000. The influence of impeller geometric parameters on the head was analyzed so that the regression equations between them at different operation points were established. With proper variables in the regression equations, the geometric parameters of impeller could then be calculated for specific design requirements. The experiment on the newly designed self-priming pump showed that the discharge and the head was 12 m³/h and 30.3 m for the sprinkler irrigation, and 18 m³/h and 21 m for drip irrigation, meeting the design requirements. The results indicated that the mathematic models established by DOE could be used to describe the relationship between the head and corresponding impeller geometric parameters at different operation conditions. The head curve became steeper as the blade angle and the blade outlet angle decreased.
Number of references:13
Main heading:Design of experiments
Controlled terms:Boundary layers - Computational fluid dynamics - Computer simulation - Design - Experiments - Geometry - Impellers - Inlet flow - Multiobjective optimization - Numerical models  - Pumps - Sprinkler systems (irrigation) - Turbulence models
Uncontrolled terms:Drip irrigation systems - Multi-operation conditions - Multi-points - Number of iterations - Operation conditions - Regression equation - Self priming pumps - Sprinkler irrigation
Classification code:408 Structural Design - 601.2 Machine Components - 618.2 Pumps - 631.1 Fluid Flow, General - 723.5 Computer Applications - 821.1 Agricultural Machinery and Equipment - 901.3 Engineering Research - 921 Mathematics - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.15.013
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 20>

Accession number:201436062571
Title:Relationship between gelatinization and gel properties of different starch and their noodles
Authors:Liao, Luyan (1); Wu, Weiguo (2)
Author affiliation:(1) Orient Science and Technology College of Hunan Agricultural University, Changsha, China; (2) Food Science and Technology College of Hunan Agricultural University, Changsha, China
Corresponding author:Wu, Weiguo
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:332-338
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Starch noodles have been a Chinese favorite food for at least 1400 years. Starch noodles are consumed as a staple food in dishes or in soups regularly in China. Starch is the main ingredient in the production of starch noodles. With the absence of gluten compared with wheat flour, the quality of starch noodles depend on the physical-chemical, thermal, and rheological properties of starch. The influence of starch on starch noodle quality is noticed as a result of the retrogradation step included in the manufacturing process. Furthermore, prerequisites for retrogradation depend on the starch properties of gelatinization and gel. The characteristics of starch noodles were mainly dependent on starch gelatinization and gel properties during the manufacturing process in the heat treatment process. After starch gelatinization forms certain flexibility and strength in the gel, the strength of the gel characteristics directly affect the processing qualities and performance of starch noodles. Many studies think starch gelatinization properties of RVA (rapid viscosity analyzer) parameters can predict the qualities of corresponding starch noodles. However, the relationship research reports on the properties of starch gelatinization and gel and the qualities of noodles are concentrated in different varieties of the same plant sources. Research in different plant sources of starch gelatinization and gel properties and starch noodles' qualities relationships remain uncertain. In order for starch properties of gelatinization and gel to predict starch noodle quality, this paper investigated the relationship between the gelatinization and gel properties of starch and the texture and cooking qualities of their starch noodles. This was conducted by studying the correlation of the gelatinization and gel properties of five original starches and their noodles' qualities and exploring the effect properties of starch have on the quality of starch noodles' parameters. The five starch materials are from mung bean, sweet potato, potato, rice, and corn. The results showed that these five starch noodles have different qualities. By evaluating the starch noodles cooking and texture qualities, the mung bean resulted as the best, followed by the potato and sweet potato, and rice and corn were the worst. The results also indicated that starch gelatinization properties and their noodles have a significant correlation. These influential parameters were related according to the p value: peak viscosity&gt; valley viscosity value&gt;attenuation value&gt;setback viscosity, final viscosity. In addition, starch gel hardness, elasticity, viscosity, and chewiness have a bigger influence on the quality of starch noodles, according to the degree of significant size value (p) in turn is: hardness&gt;viscosity&gt;chewiness&gt;elasticity. A significant correlation was seen between the quality of starch noodles and the parameters of valley viscosity, setback, resilience, chewiness, and sticky. This was considered an important way of predicting the qualities of starch noodles and can be regarded as the major indexes for starch noodle raw material selection. These research results can provide a sensitive method for monitoring the quality of starch for starch noodles production and explore a convenient method for evaluating the qualities of starch noodles. In doing so, this can provide the theory basis for starch noodles' qualities improvement.
Number of references:23
Main heading:Starch
Controlled terms:Elasticity - Forecasting - Gelation - Gels - Hardness - Quality control - Textures - Viscosity
Uncontrolled terms:Gel characteristics - Gelatinization - Heat treatment process - Manufacturing process - Noodles properties - Raw material selection - Rheological property - Starch gelatinization
Classification code:421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 631.1 Fluid Flow, General - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.1 Organic Compounds - 913.3 Quality Assurance and Control - 921 Mathematics - 933 Solid State Physics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.15.042
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 21>

Accession number:201436062553
Title:Experiment on hydraulic characteristics of shallow open channel flow on slope
Authors:Zhang, Kuandi (1); Wang, Guangqian (2); Sun, Xiaomin (1); Yang, Fan (3); L, Hongxing (3)
Author affiliation:(1) State Key Laboratory of Soil Erosion and Drylang Farming on the Loess Plateau, Northwest A and F University, Yangling, China; (2) Department of Water Conservancy, Tsinghua University, Beijing, China; (3) College of Water Resources and Architactural Engineering, Northwest A and F University, Yangling, China
Corresponding author:L, Hongxing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:182-189
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Hydraulic characteristics of overland flow are of importance in elucidating the mechanisms of soil erosion and sediment yield on slope. By a fixed-bed resistance experiment, the relationship of hydraulic parameters and the resistance characteristics for the shallow flow are quantitatively studied under conditions of six roughness beds and five gradients. Results showed that the index of the shallow flow regime exhibited a saddle-shape changing trend with increased gradient. The index of the shallow flow regime would gradually decrease with the increase of gradient when the gradient was less than 0.15 rad, but the trend was opposite when the gradient was higher than 0.15 rad. The index of the shallow flow regime presented a parabolic changing trend with increasing roughness, and the average index was 0.367. For the bed roughness less than 0.38, the flow range per unit width in unstable flow region became narrower with the increase of roughness, and the flow extended to the transitional zone; For the bed roughness greater than 0.38, the flow range per unit width in the unstable flow region gradually became wider with the increase of roughness. Generally, the shallow flow may be summarized by the category of rolling slope flow zone and transition flow zone. The Froude numbers of the shallow flow were both a power function with the flow of per unit width and the gradient, and their exponents are 0.436 and 0.278, respectively. The flow per unit width of the critical flow increased with the increase of roughness but decreased with the increase of gradient. It had a positive relationship with power 0.573 of the roughness and power 0.636 of slope, and the patterns of the shallow flow were in the critical flow and the supercritical flow. The resistance coefficient was in an opposite relationship with power 0.872 of per unit width flow, a positive relationship with power 0.445 of slope, and also an inverse relationship with the Reynolds number. However, the resistance coefficient had large difference with open channel flow, and increased with increasing roughness and slope. The increased resistance was likely to be mainly associated with the pressure drag by flow around a body and the local resistance by rolling slope flow. A formula of resistance in rolling slope flow zone was proposed based on the resistance characteristics of the shallow flow. Results from the study may provide information on the prediction of soil erosion on slope, and promote the application of open channel flow theory in overland flow.
Number of references:31
Main heading:Flow of water
Controlled terms:Buoyancy - Erosion - Experiments - Hydrodynamics - Mechanical properties - Open channel flow - Reynolds number
Uncontrolled terms:Flow regimes - Hydraulic characteristic - Hydraulic parameters - Inverse relationship - Resistance characteristics - Resistance coefficients - Shallow open channel flow on slope - Supercritical flow
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 483 Soil Mechanics and Foundations - 631 Fluid Flow - 901.3 Engineering Research - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.15.024
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 22>

Accession number:201436062552
Title:Improved approach for estimation of detachment rate of rill sediment loading flow
Authors:Zhao, Yu (1); Chen, Xiaoyan (1); Mi, Hongxing (1); Mo, Bin (1)
Author affiliation:(1) College of Resources and Environment, Key Laboratory of Eco-environments in Three Gorges Region(Ministry of Education), Southwest University, Chongqing, China
Corresponding author:Chen, Xiaoyan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:174-181
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The soil denudation caused by concentrated water flow is the primary source of sediment in an eroded rill. Soil detachment rate of sediment loading flow is not only significant for understanding the dynamic process of rill erosion but also an important parameter in soil erosion prediction and soil erosion process modeling. Laboratory simulation is an important method to study rill erosion. Previous researches have suggested an experimental method for rill erosion process study. In their method sediment laden samples are taken from different rill lengths at different time. The rill erosion process along the simulated rill is integrated from the experimental data obtained from different rills lengths. Previous experimental approach is not only disrupted the continuity of rill erosion process but also time consuming. In order to get a better understand of rill erosion process, an improved approach was used for rill erosion process study. In this newly-suggested method, sediment laden samples were taken along the rill simultaneously and the length of the experimental flume was extended to 12 m to ensure sediment loading flow can reach its transport capacity under every hydraulic conditions. A flume platform that was 12 m long and 3 m wide was used as a base to construct a flume that was 12 m long, 0.6 m wide and 0.5 m deep. The flume was sub-divided into six rills that were 0.1 m wide and 12 m long using upright PVC boards to form well-defined rills. A typical silt-loam soil with 22.34% sand, 61.35% silt and 16.31% clay particles from the Loess Plateau of China was used in the experiment. The soil was air-dried and passed through an 8-mm sieve before packed into the simulated rills. The depth of soil in the flume was 25 cm. The bottom 5 cm of the soil was packed to a bulk density of 1 500 kg/m³ to imitate the plow pan layer. The top 20 cm was packed to bulk density of 1 200 kg/m³ as the experimental layer. The soil near the PVC boards was packed slightly higher than the middle to force the water to converge and to minimize the boundary effect. Prior to the experiment, the soil was saturated with a rainfall simulator and allowed to drain for 24 h to ensure homogeneous initial soil moisture content. The experiments were conducted with five slope gradients (5&deg;, 10&deg;, 15&deg;, 20&deg;, 25&deg;) and three inflow rates (2, 4, 8 L/min) with three replicates. Sediment laden samples were simultaneously taken along the rill at the distances of 0.5, 1, 2, 3, 4, 5, 6, 7, 8, 10, and 12 m to determine the rill detachment rate along the rill. Three samples were taken at 1.0-minute intervals for each run. The results indicated that rill detachment rate decreased linearly with sediment concentration and exponentially with rill length (under slope gradients of 15&deg;, 20&deg; and 25&deg;)for all flow rates and slope gradients. That meant the soil detachment rate and sediment concentration moved was opposite to each other. Detachment rate had its maximum value when the sediment concentration was at its minimum value. This variation trend was more obvious at steeper slope gradient and higher flow rate. Both slope gradient and flow rate had a positive influence on detachment rate. Additionally, analytic result indicated that rill detachment rate was a function of sediment concentration, rill length, flow rate and slope gradient. The detachment rate obtained using the traditional method and the ones from this study were compared. The correlation coefficient of the two data sets is 0.917 which indicated that detachment rate can be reliably estimated by the two methods. But the newly-suggested method was more precise, time efficient and easy to operate. The study provided a guideline for rill erosion prevention and establishment of rill erosion prediction model.
Number of references:30
Main heading:Erosion
Controlled terms:Experiments - Flow rate - Forecasting - Sediment transport - Sedimentation - Silt - Soil moisture - Soils
Uncontrolled terms:Detachment rate - Eroding rills - Erosion process - Flume experiment - Sediment loading
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 483 Soil Mechanics and Foundations - 483.1 Soils and Soil Mechanics - 631 Fluid Flow - 802.3 Chemical Operations - 901.3 Engineering Research - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.15.023
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 23>

Accession number:201436062535
Title:Virtual test method for motorcycle frame based on multi-axes road simulation using excitation spectrum
Authors:Zou, Xihong (1); Xiong, Feng (1); Yuan, Dongmei (2); Yi, Peng (4)
Author affiliation:(1) Key Laboratory of Manufacture and Test Techniques for Automobile Parts, Ministry of Education, Chongqing University of Technology, Chongqing, China; (2) Mechanical Engineering Institute, Chongqing University of Technology, Chongqing, China; (3) Chongqing Jianshe Motorcycle Co., Ltd, Chongqing, China; (4) Chongqing Academy of Science and Technology, Chongqing, China
Corresponding author:Zou, Xihong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:39-45
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Motorcycle frame is the key load-bearing part of vehicle, its fatigue reliability, stiffness, strength, quality and other factors play a decisive role in vehicle's control stability and occupant comfort. New frame products must pass the reliability test before put into market. However, current frame fatigue reliability tests mainly use road test and testing ground test, which are time-energy consuming and the results are easily affected by environmental factors; Indoor bench tests at present mainly use single axial single incentive or single axial multi incentive mode. The motorcycle frame installation and constraints on the vehicle are very complex, the actual driving loads are complicated and changeable, thus multi-axial loads on motorcycle frame due to road excitation during actual driving could not be simulated or simulation precision is low, prone to over or under test. While the computer simulation technology development provides a new solution to dynamic performance analysis and fatigue reliability evaluation of vehicles and their parts, which including complete 3D entity model building online, creating a virtual laboratory, a virtual running environment and realizing virtual test and evaluation. For accurate and efficient analysis and evaluation of motorcycle frame fatigue reliability, a multi-axes road simulation test method for motorcycle frame based on time-frequency domain error weighting and force-displacement hybrid control was put forward. A motorcycle frame multi-axes road simulation test bench was built with American MTS road simulation test device, which was arranged with two actuator input channels in horizontal axial and vertical axial. As the motorcycle frame multi-axes road simulation test system is a multiple input multiple output system, the remote parameter matrix control strategy was applied to iterate and reproduce actual driving load spectrum. As the frame front fork and shock absorber were substituted by rigid frame fixture, in the horizontal direction, the frame dynamic response was more effective to the force loading, so the horizontal actuator used force control mode and loaded force spectrum. In the vertical direction, the system used inertial loading and frame dynamic response was more effective to displacement loading, so the vertical actuator was selected displacement control mode and loaded displacement spectrum. The motorcycle frame actual road load spectra were collected and multi-axes road simulation test bench was developed. With the simulation test bench, the multi-axes road simulation test was conducted based on force-displacement hybrid control under time and frequency domain with error weighting coefficient of 0.5. The simulation iteration precision of frame actual road load spectrum achieved 93%. Therefore the multi-axes road simulation excitation spectrum were extracted. The HYPERWORKS and ADAMS were applied in building the virtual rigid-flexible coupled multi-axes road simulation test platform with reference of the actual motorcycle frame multi-axes road simulation test system. Simulation analysis was conducted with the multi-axes road simulation excitation spectrum as input and the outcomes were verified by actual multi-axes road simulation test, thus the virtual test method for motorcycle frame based on multi-axes road simulation excitation spectrum were established. The results show that, the curve trend and amplitude of simulation results coincide well with test results in time and frequency domain, only slight amplitude deviation exists near frequency value 13 and 24 Hz, while the frequency curve RMS error is within 10%. Thus the virtual test method based on multi-axes road simulation excitation spectrum could be well applied to motorcycle frame fatigue reliability assessment.
Number of references:28
Main heading:Quality control
Controlled terms:Actuators - Computer simulation - Dynamic response - Excited states - Experiments - Frequency domain analysis - Loads (forces) - MIMO systems - Motorcycles - Reliability analysis  - Roads and streets - Virtual reality
Uncontrolled terms:Computer simulation technology - Dynamic performance analysis - Excitation spectrum - Fatigue reliability evaluations - Hybrid controls - Multi-axes road simulation - Multiple input multiple output system - Time frequency domain
Classification code:406.2 Roads and Streets - 408 Structural Design - 408.1 Structural Design, General - 421 Strength of Building Materials; Mechanical Properties - 632 Hydraulics, Pneumatics and Related Equipment, and Fluidics - 662.2 Smaller Vehicles - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 731.1 Control Systems - 901.3 Engineering Research - 913 Production Planning and Control; Manufacturing - 913.3 Quality Assurance and Control - 931.3 Atomic and Molecular Physics - 961 Systems Science
DOI:10.3969/j.issn.1002-6819.2014.15.006
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 24>

Accession number:201436062532
Title:Improvement and experiment on cutting system of small whole-stalk sugarcane harvester
Authors:Ma, Fanglan (1); Wei, Rongfa (1); Fan, Zhida (1); Zhao, Jing (1)
Author affiliation:(1) College of Mechanical Engineering, Guangxi University, Nanning, China
Corresponding author:Ma, Fanglan
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:18-24
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The cutting system is the key component of small whole-stalk sugarcane harvester and it is located in front of the machine. Whether it can convey the sugarcane smoothly into the next process or not after cutting is directly related to the working performance of the machine. Currently the main problems of the original prototype include serious blocking, lower cutting quality, less efficiency and higher impurity during harvesting, which seriously hinder the application of the harvester. In order to improve cutting quality and to reduce the sugar stalks loss under the premise of low stool damage rate, some technical improvements were taken. The cutting device, layout and lifting way of the cutting system of the original machine were modified, and an aggressive knock-down roller was added in frond of the cutting system.
Number of references:19
Main heading:Harvesters
Controlled terms:Experiments - Feeding - Rollers (machine components) - Speed - Sugar cane
Uncontrolled terms:Damage rate - Friction coefficients - Mechanical design - Production efficiency - Technical improvement - Transport mechanism - Whole-stalk sugarcane harvesters - Working performance
Classification code:601.2 Machine Components - 691.2 Materials Handling Methods - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 901.3 Engineering Research - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.15.003
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 25>

Accession number:201436062564
Title:Evaluation method for engineering technology of rural domestic sewage treatment based on fuzzy integral model
Authors:Shen, Fengju (1); Zhang, Keqiang (1); Li, Junxing (1); Huang, Zhiping (1); Zheng, Xiangqun (1); Tang, Jiewei (2)
Author affiliation:(1) Institute of Agro-environmental Protection, Ministry of Agriculture, Tianjin, China; (2) Rural Energy and Environment Agency, Ministry of Agriculture, Beijing, China
Corresponding author:Zhang, Keqiang
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:272-280
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Rural domestic sewage is the main source of pollution of rural water pollution, including all kinds of washing water of daily life, kitchen waste water and animal wastes. Most of the rural domestic sewage flow directly into rivers, lakes and reservoirs. As a result, the content of nitrogen, sulfur, phosphorus increased and leading to the eutrophication of water body. It not only damaged the water environment but also affected the health of human body seriously. The difficulty of rural domestic treatment is that rural domestic sewage is widely distributed and has a big difference between areas. On the other hand, the rural sewage quality and quantity have great fluctuations. Due to the poor infrastructure construction, the sewage pipe network is not perfect in rural area. At the same time, the weak rural economy and the lack of professional sewage treatment technology and management personnel, make the rural sewage treatment and resource utilization degree inferior to the city sewage treatment plants. Currently, the rural domestic sewage emission leads to the problems of agricultural nonpoint source pollution and shortage of water resources in rural areas in China. The protection of rural water environment is the guarantee of the development of agricultural production and construction of beautiful countryside. The wastewater treatment in rural areas is the need to change the disorderly discharge situation of rural life sewage, and improve the living conditions of farmers. Because of different circumstances in thousands of counties, the rural domestic sewage treatment must accommodate one's measures to local conditions and classification guidance. It is very important to put forward the practical domestic sewage treatment methods and measures. The government departments attach great importance to this issue, which means that this question must be addressed in the coming construction and development of rural areas. Scientific research institutions have the responsibility to carry out scientific experiments and studies to support resolving this problem. In this study, a serial surveys were conducted on the status quo of rural domestic sewage pollution, emission characteristics, water quality characteristics and the existing treatment processes and technologies. Also site visits of the typical rural domestic sewage treatment works in the rural areas were carried through to learn and understand the treatment effect, operating conditions and existing problems of the projects. With choosing and analyzing the evaluation indexes from economic, technical characteristics and environmental effects, the evaluation index system of rural domestic sewage treatment technologies was constructed. With integrated analytic hierarchy process and entropy method, the index weights were determined by considering the subjective and objective weighting methods. Based on hierarchical fuzzy integral model, a comprehensive evaluation was made on 15 kinds of domestic sewage treatment engineering techniques existing and commonly used in rural areas. Through sorting the final results, 10 kinds of more excellent treatment technologies were selected, such as ecological filter tank, ecological pond, anaerobic (facultative) pond, constructed wetland, integrated purification tank, anaerobic biological contact oxidation constructed wetland. The research can provide a reference for the construction of rural domestic sewage treatment works.
Number of references:30
Main heading:Rural areas
Controlled terms:Agricultural wastes - Agriculture - Environmental technology - Eutrophication - Filtration - Human resource management - Integral equations - Lakes - Mathematical models - Pollution  - Reservoirs (water) - River pollution - Sewage - Sewage treatment - Sewage treatment plants - Tanks (containers) - Wastewater treatment - Water pollution - Water quality - Water resources  - Wetlands
Uncontrolled terms:Combination weighting method - Fuzzy integral - Fuzzy measures - Rural domestic sewages - Synthetic evaluation
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 441.2 Reservoirs - 442.2 Land Reclamation - 444 Water Resources - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 453 Water Pollution - 454 Environmental Engineering - 454.2 Environmental Impact and Protection - 619.2 Tanks - 802.3 Chemical Operations - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.5 Agricultural Wastes - 912.4 Personnel - 921 Mathematics - 921.2 Calculus
DOI:10.3969/j.issn.1002-6819.2014.15.035
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 26>

Accession number:201436062567
Title:Establishment and verification of energy consumption model of fruits and vegetables fresh-keeping transportation container with controlled atmosphere by liquid nitrogen injection
Authors:Yang, Songxia (1); L, Enli (1); Lu, Huazhong (1); L, Shengping (1); Cen, Kanghua (1)
Author affiliation:(1) Key Laboratory of Key Technology on Agricultural Machine and Equipment, Ministry of Education, South China Agricultural University, Guangzhou, China; (2) College of Engineering, South China Agricultural University, Guangzhou, China
Corresponding author:Lu, Huazhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:299-308
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:China is a country that produces and consumes large amounts of fruits and vegetables. During fresh-keeping transportation, energy consumption rises with the increase of traffic volume of fruits and vegetables. The fresh-keeping transportation container with controlled atmosphere by liquid nitrogen injection is an advanced and efficient equipment for transporting fruits and vegetables. However, there is little research on the energy consumption regulations of this kind of fresh-keeping transportation container so this article puts forward a research method. Fresh-keeping transportation with controlled atmosphere by liquid nitrogen injection for fruits and vegetables keeps the temperature, relative humidity, and oxygen volume fraction of the transportation container in a state of relative balance, which could meet the demand for fruit and vegetable fresh-keeping. However, due to the influence of heat transferring towards the container, cold consuming of electrical appliances, cold consuming of fruits and vegetables, heat transferring by door opening, aperture heat leaking, container pre-cooling, and solar radiation in transportation, the equilibrium states of fresh-keeping environment in the container is broken. In addition, heat and mass transferring between the inside and outside of the container has begun. At this time, the fresh-keeping equipments started to keep the equilibrium states of fresh-keeping environment, and then energy consumption was generated. The fresh-keeping equipments of controlled atmosphere fresh-keeping transportation container by liquid nitrogen injection consist of refrigeration, humidification, and controlled atmosphere system, and the energy consumption generated from these three equipments. Finally, the energy consumption model was established based on the analysis of the heat and mass transfer and energy consumption in refrigerating, humidifying, and injecting. After the energy consumption model was set up, the verification experiment was carried out using litchi as testing material and was based on fresh-keeping transportation platform with controlled atmosphere by liquid nitrogen injection for fruits and vegetables. The fresh-keeping transportation platform can adjust the temperature, relative humidity, and oxygen volume fraction in the container automatically and intelligently through refrigeration, humidification, and controlled atmosphere system, creating a suitable fresh-keeping environment for the litchi. Results indicated that the energy consumption was mainly composed of the controlled atmosphere energy, refrigerating energy consumption, and humidifying energy. The theoretical energy consumption obtained through the energy consumption model was basically consistent to the experimental energy consumption with the average relative error of 11.86%&plusmn;4.29%. The theoretical liquid nitrogen consumption value was basically consistent to the experimental liquid nitrogen consumption mass with the average relative error of 11.60%&plusmn;3.51%. The total refrigerating capacity from the controlled atmosphere process was associated with the controlled atmosphere volume of the container. What's more, by consuming less energy, the controlled atmosphere could produce a large total refrigerating capacity that accounted for about 22% of the total theoretical refrigerating capacity in the experimental verification. This research provides a reference for optimizing the equipments of controlled atmosphere transportation by liquid nitrogen injection and saving energy of fruits and vegetables during fresh-keeping transportation.
Number of references:34
Main heading:Energy utilization
Controlled terms:Containers - Equipment - Fruits - Heat transfer - Liquid nitrogen - Models - Protective atmospheres - Refrigeration - Sun - Transportation  - Vegetables - Volume fraction
Uncontrolled terms:Average relative error - Controlled atmosphere systems - Energy consumption model - Experimental verification - Fresh keepings - Heat and mass transfer - Refrigerating capacity - Theoretical energy consumption
Classification code:431 Air Transportation - 432 Highway Transportation - 433 Railroad Transportation - 434 Waterway Transportation - 525.3 Energy Utilization - 641.1 Thermodynamics - 641.2 Heat Transfer - 644.4 Cryogenics - 657.2 Extraterrestrial Physics and Stellar Phenomena - 691 Bulk Handling and Unit Loads - 694 Packaging - 804.2 Inorganic Compounds - 821.4 Agricultural Products - 901 Engineering Profession - 902.1 Engineering Graphics
DOI:10.3969/j.issn.1002-6819.2014.15.038
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 27>

Accession number:201436062533
Title:Effective experiment of elevated wind machine for frost protection with long blade in large apple orchards
Authors:Yin, Xianzhi (1); Wang, Yanfeng (2); Ding, Ruijin (2); Fu, Shuangxi (2); Zhang, Fengwei (2); Chen, Qi (2)
Author affiliation:(1) Institute of Arid Meteorology, China Meteorological Administration, Key Laboratory of Arid Climatic Changing and Reducing Disaster of Gansu Province, Lanzhou, China; (2) Gansu Weather Modification Office, Lanzhou, China
Corresponding author:Yin, Xianzhi
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:25-32
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In recent years, the crops have severely suffered from frost damage with the deterioration of the global climate. Conventional methods of frost protection, such as smoking, covering, and irrigation may be effective in many cases, but they are time-consuming, and some methods even easily caused environmental contamination. So study of scientific and high-effective artificial frost prevention equipment has become very necessary and an urgent need. Most wind machines for frost protection are still in the pilot stage at home and abroad, and their height and blade length, etc, are not for taller plants, such as apple trees, peach trees, and cherry trees. The Gansu meteorology department, using the principle of disturbing the air of mechanical power, invented the first domestic elevated wind machine for frost protection with a long blade, which proved the feasibility of frost protection by air in disturbing surface layer. The machine construction has the main components as follows: blade, pipe tower, fan base, underground base, engine and ladder. In order to study the effect of frost prevention and the extent of protection for an elevated wind machine, the instrumentation layout was as follows: at a distance of 53 m from the wind machine, installing a 10 m gradient observation tower of temperature within protected areas, and at a distance of 190 m from the wind machine, also installing a 10 m gradient observation tower of temperature outside protected areas as the effect of frost prevention control. Two gradient tower of temperature at 1.0, 2.0, 3.0, 4.0, 5.0, 8.0 and 10 m from the ground installed a temperature sensor respectively, which observed vertical temperature distribution; also at 2 m from the ground install a humidity sensor observed relative humidity. A projector to the ground of the wind wheel rotation axis of the wind machine for the center line, arranged the horizontal distribution of an observation point at intervals of 10 m, a total of 10 observation points, and each observation point 1, 2 and 3 m from the ground were erecting a portable anemometer for wind observation. In this paper, based on the contrast test observation data of the processes of a strong decrease in temperature from October 19 to 21,2013, the frost protection effect of the first self-designed domestic elevated wind machine for frost protection with a long blade was evaluated. The main analysis results were as follows: 1) Under the temperature inversion condition, the upper and lower air disturbance caused by one elevated wind machine with a 6m diameter blade of 12 kW power and 8.5 m in height made the temperature inversion disappear and the temperature within 1-3 m greatly increased. Relative humidity decreased rapidly, effectively preventing the generation of frost in the protected area. 2) The disturbances-affected area of strong wind was about 20 m, and wind speeds at 3, 2 and 1m from the ground were 4.0, 2.1 and 1.6 m/s respectively. The effective protection range of one wind machine was 20 m to 100 m, within level range of 20-100 m, wind speed changes of 1-3 m showed a reduced trend with fluctuations. The effective protection area of one wind machine was 1.73-3.07 hm². The result of the research provides a reference for scientific and high-effective artificial frost prevention and promotion of an elevated wind machine for frost protection with a long blade use.
Number of references:30
Main heading:Frost protection
Controlled terms:Agricultural machinery - Atmospheric temperature - Climatology - Conservation - Environmental protection - Forestry - Fruits - Machine components - Orchards - Temperature  - Towers - Wind
Uncontrolled terms:Conventional methods - Environmental contamination - Evaluation - Horizontal distribution - Machine construction - Temperature inversions - Vertical temperature distribution - Wind machines
Classification code:402.4 Towers - 443 Meteorology - 443.1 Atmospheric Properties - 454 Environmental Engineering - 454.2 Environmental Impact and Protection - 601.2 Machine Components - 641.1 Thermodynamics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control
DOI:10.3969/j.issn.1002-6819.2014.15.004
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 28>

Accession number:201436062556
Title:Optimization method for crop growth features based on improved locality preserving projection
Authors:Jia, Dongyao (1); Hu, Po (1); Zou, Shengxiong (1)
Author affiliation:(1) Advanced Control Systems Laboratory, School of Electronic and Information Engineering, Beijing Jiaotong University, Beijing, China
Corresponding author:Jia, Dongyao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:206-213
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Nowadays, the evaluation for crop growth is based on various growth characteristics, which often brings a huge amount of information processing. Furthermore, the complex information can not directly reflect some key features of crops. Thus, the feature extraction and optimization plays an important role in the process. In this paper, the locality preserving projection (LPP) is used to achieve the dimensionality reduction of high dimensional data while keeping the invariance of its internal local structure. After being projected via the algorithm, the adjacent sample is able to maintain the original neighboring state while the original distant samples don't keep the old state. Obviously, this result is not satisfactory for data optimization. In order to strengthen the effect of category separation, firstly, the dimension of sample data is preliminary reduced by using two-dimensional principal component analysis (2DPCA) to retain the spatial information. Secondly, two sub-graphs (gathered sub-graph and separated sub-graph) instead of original nearest neighbor graph are used to describe the relationship between homogeneous and heterogeneous data. The gathered sub-graph is improved on the basis of K-nearest neighbor graph. The addition of category information makes the homogeneous non-adjacent samples stay closer to each other after projection. The separated sub-graph is constructed to solve the problem that the application of K-nearest neighbor graph may reduce the accuracy of classification when the data are projected into low-dimensional space. Then the optimized global matrix and the improved objective function are provided to design the complete optimization method for feature extraction. Through the above steps, the category information of sample data is added for LPP algorithm. Finally, the feature parameters set are obtained by improved LPP algorithm to extract local information of samples. The data of crop growth features are further projected to low-dimensional space. The final extracted information is able to replace the original sample data without losing the data which can reflect the key information of sample set. In order to evaluate the performance of improved LPP algorithm to achieve dimensionality reduction and optimizing for crop growth characteristics, a set of data from cabbage was chosen as test sample. In the process of dimensionality reduction from 30 to 10 using different algorithms (PCA, 2DPCA, LPP and improved LPP), the improved LPP has higher overall performance with less running time, which is only longer than Basic LPP algorithm. By analyzing the performance of improved LPP algorithm for dimensionality reduction, the data of some cabbage and lettuce were chosen as test data. The contrast experiments using different algorithms (PCA, 2DPCA, LPP and improved LPP) for dimensionality reduction were carried out, and all the test data in the database achieved dimensionality reduction via the above-mentioned algorithms. Meanwhile, it accomplished data classification by SVM after accomplishing dimensionality reduction. The experiments show that the improved LPP algorithm has better adaptability, and the highest SVM classification accuracy rate of this method can reach up to 96%. Compared with other methods, the improved LPP has superior performances in terms of multidimensional data analysis and optimization. The method has good prospects, and is able to meet the demands for the information perception of new agriculture as well as the optimization of crop growth characteristic parameters.
Number of references:25
Main heading:Data reduction
Controlled terms:Algorithms - Classification (of information) - Crops - Data mining - Data processing - Experiments - Feature extraction - Monitoring - Optimization - Principal component analysis  - Separation
Uncontrolled terms:Accuracy of classifications - Feature optimizations - Growth feature - K-nearest neighbor graphs - Locality preserving projections - Multi-dimensional data analysis - Two dimensional principal component analysis (2DPCA) - Two-dimensional principal component analysis
Classification code:716 Telecommunication; Radar, Radio and Television - 716.1 Information Theory and Signal Processing - 723 Computer Software, Data Handling and Applications - 723.2 Data Processing and Image Processing - 802.3 Chemical Operations - 821.4 Agricultural Products - 901.3 Engineering Research - 921 Mathematics - 921.5 Optimization Techniques - 922.2 Mathematical Statistics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.027
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 29>

Accession number:201436062570
Title:Appropriate aging time improving quality of yak meat
Authors:Zhang, Li (1); Wang, Li (1); Zhou, Yuchun (1); Sun, Baozhong (2); Yu, Qunli (1); Ji, Qiumei (3); Guo, Zhaobin (1)
Author affiliation:(1) College of Food Science and Engineering, Gansu Agricultural University, Lanzhou, China; (2) Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, China; (3) Tibet Institute of Animal Husbandry, Lhasa, China
Corresponding author:Sun, Baozhong
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:325-331
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:There are more than 16 million yaks in China, which accounting for about 95% of total amount in the world. The yak beef could be a new resource for meat industry in China with high protein, low fat and unique flavour. However, the commercial potential of yak beef is limited because of the poor tenderness of yak beef. The aging could be a simple and effective method to improve tenderness of beef especially prolonged aging time more than 14 d. In order to investigate the prolonged aging time on quality traits of yak meat, the pH value, tenderness (WBSF, Warner Bratzler shear force), water holding capacity (WHC, including cooking loss and press loss) and chroma (L^*, a^* and b^*) of M. longissimus dorsi removed from yak within postmortem 2 h were determined during 21 d aging after vacuum packaging, and the changing patterns of quality traits of yak beef were analyzed through standardization of variables and kinetic model. It was found that there were significant variations during 21 d aging for quality traits (P&lt;0.05) except b^* value. The main variation of pH values during postmortem aging occurred in 3 d of early postmortem, while yak beef aging for 21 d did not have a lower pH value than those aging for 7 d. The aging of 7 d decreased the WBSF by 43 N, but the average WBSF of yak beef aging for 7 d still higher than 50 N. The WBSF of yak beef aging for 21 d was lower to 30 N, which was 47% significantly lower than that aging for 7 d (P&lt;0.05). The cooking loss of yak beef significantly increased from 40.4% to 51.5% when aging time was prolonged from 7 d to 21 d (P&lt;0.05), while the prolonged aging of 21 d did not have a significant effect on press loss of yak beef (P&gt;0.05). The L* value significantly decreased with aging time during early aging of 7 d (P&lt;0.05), but there was no significant difference on L^* value between yak beef aging for 21 d and 7 d (P&gt;0.05). However, a^* value (redness) of yak beef significantly increased with prolonged aging time, and a^* value of yak beef aging for 21 d was 32% higher compared to that aging for 7 d (P&lt;0.05). Meanwhile, the changing pattern of quality traits of yak beef with significant change during aging was also investigated through standardization of variables and kinetic model analysis. It was found that the quadratic function had best predicting performance on quality traits of yak meat with coefficients of determination R² ranged from 0.90 to 0.98, through comparing fitting degree of linear, exponential and quadratic functions. The changes of pH value, shearing force, press loss and L^* were characterized by the convex function with negative second derivative, while cooking loss and a^* value were characterized by the concave function with positive second derivative. It shows that the prolonged aging can be beneficial to improvement of tenderness, but has adverse effects on water holding capacity and meat color. Conclusively, different quality traits have different changing patterns and vary on different phases of aging.
Number of references:28
Main heading:Meats
Controlled terms:Functions - Kinetic parameters - Kinetic theory - pH - Presses (machine tools) - Processing - Quality control - Standardization - Thermal processing (foods)
Uncontrolled terms:Aging time - Commercial potential - Kinetic model analysis - Longissimus dorsi - Prediction model - Quadratic function - Second derivatives - Water holding capacity
Classification code:603.1 Machine Tools, General - 801.1 Chemistry, General - 822.2 Food Processing Operations - 822.3 Food Products - 902.2 Codes and Standards - 913.3 Quality Assurance and Control - 913.4 Manufacturing - 921 Mathematics - 931 Classical Physics; Quantum Theory; Relativity - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.15.041
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 30>

Accession number:201436062531
Title:Design and optimization of transplanting mechanism with B-spline non-circular planet gear train for rice pot seedling
Authors:Zuo, Yanjun (1); Cao, Peng (1); Zhao, Yun (1); Yu, Xiaoxu (1); L, Cheng (1); Zhang, Zhichao (1); Zhang, Hao (1)
Author affiliation:(1) College of Engineering, Northeast Agricultural University, Harbin, China; (2) Promotion and Collaborative Operation Innovation Center of Heilongjiang Food Capacity, Harbin, China
Corresponding author:Zhao, Yun
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:10-17
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The pot seedling transplanting has the advantages of non-hurting root and no need of recovering period, so it can extend the crop growing period, increase and bring forward the effective tillering, which is very important to the food security. Since Japan invented the first transplanter for rice pot seedling in 1975, large agricultural machinery companies have producted their own models in succession, such as Yanmar, Iseki and so on. The materials and manufacture technologies have been improved through the forty years development, but the basic structure and working principle are still the same. All the transplanting machines use 3 sets of mechanism to complete 3 kinds of movements of picking, transporting and planting. The existing machines have the disadvantages of complex structure, high cost and low efficiency. In domestic, the rice pot seedling transplanting machine uses double cranks to complete the 3 kinds of movements, it has relatively simple mechanism, and is suitable for the rice pot seedlings transplanting, but the problems of severe vibration and low efficiency are still existent. According to the above problems, the paper adopted the cubic non-uniform rational B-spline curve theory to fit non-circular gear pitch curve with coincidence of first and last data points as a closed curve. The shape of non-circular gear pitch curve was controlled and expressed through selecting the 13 data points, a new rotary planet gear train mechanism with non-circular gear was developed for rice pot seedling transplants. Through the kinematic analysis of the mechanism, the attitude and sharp point trajectory objective functions of seedling clip were built and transformed into the optimization mathematics model based on optimization of target determined. A computer aided analysis and optimization software of the transplanting mechanism with non-circular planet gear train for rice pot seedling was developed on the MATLAB GUI platform. Through adjusting data points by the man-machine interaction, the attitude and sharp point trajectory of seedling clip were optimized, and a set of structural parameters were obtained to meet the requirements of the rice pot seedling transplants. A three dimensional model was built in software of UG 8.0, and input to software of Admas 2010. The simulation results show that, both track results of theoretical analysis and virtual prototype experiment are fundamentally consistent, so the correctness of the kinematics mathematical model was verified by the virtual experiment. The research can provide a theoretical basis for developing transplanting mechanisms for rice pot seedling.
Number of references:17
Main heading:Splines
Controlled terms:Agricultural machinery - Curve fitting - Food supply - Functions - Gears - Interpolation - Mathematical models - MATLAB - Mechanisms - Transplants  - Virtual reality
Uncontrolled terms:B-spline - Design and optimization - Non-circular gears - Non-uniform rational B-splines - Planetary gear train - Rice pot seedling - Three-dimensional model - Transplanting mechanisms
Classification code:404.2 Civil Defense - 462.4 Prosthetics - 601.2 Machine Components - 601.3 Mechanisms - 723 Computer Software, Data Handling and Applications - 821.1 Agricultural Machinery and Equipment - 921 Mathematics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.15.002
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 31>

Accession number:201436062545
Title:Mechanism analysis of vibration and noise for centrifugal pump working as turbine
Authors:Dai, Cui (1); Dong, Liang (1); Kong, Fanyu (1); Feng, Zizheng (1); Bai, Yuxing (1)
Author affiliation:(1) Research Center of Fluid Machinery Engineering and Technology, Jiangsu University, Zhenjiang, China
Corresponding author:Dai, Cui
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:114-119
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Centrifugal pumps as turbine (PAT) are widely used in the petroleum and chemical industry with reasonable efficiency and low cost investment. And it represents the primary source of vibration and acoustic energy in industrial pipeline system. The amount of emitted energy may vary significantly between different designs and it is generally not well known. In order to better understand the flow-induced vibration and noise characteristics of centrifugal pump in reversible turbine operation, a single grade end suction centrifugal pump was chosen as research object. The fluid flows into the PAT through the outlet in pump mode and flows out through the inlet. A synchronous acquisition of performance parameters and vibration and noise signals were realized on the basis of INV3020C data acquisition system and performance test system in an open test loop. The liquid is pressurized through the booster pump, and then the high pressure liquid impacts the turbine impeller to make it rotate. The dynamometer consumes and measures the turbine's energy. The operating condition was adjusted by regulating the frequency of frequency converter to change the booster pump's capacity. Experimental studies on the vibration characteristic at different monitoring positions and acoustic characteristic at the upstream and downstream of PAT were carried out on the test bench, during which the rule and frequency characteristics of vibration and noise versus rotating speed were investigated at variable and constant flow rates. The vibration and flow noise signals were collected within 30 s using acceleration sensors and hydrophone at a sampling frequency of 20 kHz. The vibration measurements were performed on the bearing, pump casing, the inlet and outlet flange and the pump foot in horizontal and vertical directions with acceleration sensors (INV9822A). The noise was measured with flush-mounted hydrophones (ST70) located at 260 mm upstream and 400 mm downstream of PAT, which were four times of pipe diameters. The signals were amplified and recorded by INV3020C data acquisition system and FFT was used for computing the spectra with the Hanning window for reducing the spectrum leakage. Experimental results show that, with the increase of rotational speed, the head and shaft power of PAT increases, and the highest efficiency point moves to larger flow rate with wider high-efficiency range. Under a certain speed, the vibration acceleration under the same monitoring point grows with the increase of flow rates. Meanwhile, the vibration energy of PAT is focused on the high frequencies, and the vibration enhances with the increase of rotating speed. The vibration strength of volute is higher than that of other measuring points for larger flow rates. The vibration strength of each measuring point comes mainly from the horizontal direction. Under a certain speed, the sound pressure level gradually grows with the increase of flow rates. Because the noise mainly comes from the interaction of blade and tongue closer to the outlet, and the radiated noise is hindered by the casing and impeller, the sound pressure level of downstream is higher than that of upstream under the same flow rate. The total sound pressure level basically increases with the increase of rotating speed.
Number of references:29
Main heading:Acoustic noise
Controlled terms:Acoustic variables measurement - Acoustic wave transmission - Centrifugal pumps - Chemical industry - Experiments - Flow rate - Hydrophones - Inlet flow - Investments - Piping systems  - Pumps - Rotating machinery - Turbines
Uncontrolled terms:Acoustic characteristic - Data acquisition system - Flow induced vibrations - Frequency characteristic - Performance parameters - Synchronous acquisition - Vibration characteristics - Vibrations
Classification code:402 Buildings and Towers - 601.1 Mechanical Devices - 612.3 Gas Turbines and Engines - 618.2 Pumps - 631 Fluid Flow - 631.1 Fluid Flow, General - 751 Acoustics, Noise. Sound - 752.1 Acoustic Devices - 805 Chemical Engineering, General - 901.3 Engineering Research - 911.2 Industrial Economics
DOI:10.3969/j.issn.1002-6819.2014.15.016
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 32>

Accession number:201436062557
Title:Loss research on wireless sensor network signal transmission in persimmon orchard
Authors:Guo, Congcong (1); Han, Wenting (1); Wang, Yi (1)
Author affiliation:(1) College of Mechanical and Electronic Engineering, Northwest A and F University, Yangling, China; (2) Institute of Water Saving Agriculture in Area Regions of China, Northwest A and F University, Yangling, China
Corresponding author:Han, Wenting
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:214-221
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:To explore a wireless sensor network (WSN) system and node deployment in persimmon orchards, this paper focused on the wireless network signal transmission under the 2.4 GHz radio channel in the persimmon orchard when it was in the germination stage, young leaves stage, and flowering stage, three growth periods. A row of persimmon tress in the growth period was selected. By adjusting the height and distance of the node and father node, the distance from three different heights from 0.80 meters at the bottom of the tree and 1.80m at the most luxuriant foliage location to 2.80 meters at the top of the canopy wee measured. Persimmon trees were measured for each growth period resulting in 72 groups of data. Results showed the LQI value with the change of the distance, the sine curve type attenuation trend, and the difference was obvious in the three growth periods. The radio signal attenuation data measured the worst minimal in the flowering stage, because the branches and leaves of signal reflection, refraction, and absorption was the most serious in this period. It is showed that the best effective transmission distance of each column of trees was 38m when child nodes and father nodes are on the top of the canopy (2.80 m) in germination, while in the young leaves stage, the height of the child nodes and father nodes are located in the top of the canopy, when the node is the best place to pitch 32m. In the flowering stage, child nodes and father nodes are on the top of the canopy, and the best distance is 26m. In the case when plant height is not very high, when the device is placed on top of the node, the wireless sensor networks optimal signal transmission distance changes as the degree of lush foliage plants is smaller and smaller. During the experiment, because the orchard in the wild environment was susceptible to the wind, the corresponding external factors, such as the difference of the instantaneous value, sometimes the LQI was big. Based on two data sets, curve fittings were established in the 2.4GHz channel signal attenuation model, which cubic polynomial model maximum correlation was coefficient R squared for an optimal model. A model of R value was the biggest of all. In the germination stage, R squared was 0.754-0.958; in the young leaves stage it was 0.805-0.979; and in the flowering stage it was 0.758-0.991. Wireless sensor network research on orchard signal transmission loss provided the technical basis for the deployment of wireless sensor network nodes in orchards.
Number of references:21
Main heading:Sensor nodes
Controlled terms:Cultivation - Data transfer - Forestry - Mathematical models - Models - Orchards - Plants (botany) - Sailing vessels - Wireless sensor networks
Uncontrolled terms:Cubic polynomials - Different heights - Effective transmission - Instantaneous value - Link quality indicators - Radio channels - Signal reflection - Signal transmission
Classification code:461.9 Biology - 674.1 Small Marine Craft - 722 Computer Systems and Equipment - 723.2 Data Processing and Image Processing - 732 Control Devices - 821.0 Woodlands and Forestry - 821.3 Agricultural Methods - 902.1 Engineering Graphics - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.15.028
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 33>

Accession number:201436062546
Title:Evapotranspiration estimation for oasis transect in middle reach of Heihe river basin based on remote sensing
Authors:Lian, Jinjiao (1); Huang, Mingbin (2); Li, Xingxian (1); Liu, Wenjuan (3)
Author affiliation:(1) College of Resources and Environment, Northwest A and F University, Yangling, China; (2) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Northwest A and F University, Yangling, China; (3) College of Agronomy, Ningxia University, Yinchuan, China
Corresponding author:Huang, Mingbin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:120-129
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The Heihe River Basin is the second largest inland river basin in the arid area of Northwestern China, and the oasis in its middle reach has 95% of the total arable land and uses 68% of the total water resources in whole basin. Because evapotranspiration (ET) from the oasis is one of the most important components in water consumption, it is very important to study the ET in various land uses for water resource management and allocation in whole basin. The objective of this study was to estimate ET values for different land uses at a spatial scale of 16 km &times; 20 km in the middle reach oasis of Heihe river basin using remote sensing method. The main challenge of this study was to find a method to extrapolate instant ET values, which were estimated from the remote images, to monthly or seasonal actual ET (AET) values. In this study, a representative transect was selected to analyze the spatial distribution and temporal change of ET for different land cover types in the middle reach of the Heihe river basin. Seven qualified Landsat TM images for the studied transect were obtained during June to August in 2011. The surface energy balance model of SEBAL-METRIC and meteorological data were used to calculate the transient ET and daily reference ET (ET<inf>0</inf>) when the Landsat passed the studied region. The ratio of instant ET/ET<inf>0</inf> was extrapolated to daily value using a sinusoidal function, while the daily ratio of ET/ET<inf>0</inf> was assumed to be constant for a short period of 5 to 24 days for estimating a cumulative ET for different land uses in the transect. The comparison of daily ET values obtained by an eddy covariance system and remote sensing method showed the SEBAL-METRIC model combined with Landsat TM image and ET<inf>0</inf> can provide reliable estimation of ET for different land cover types with an average relative error of 10.2%. The ET values varied from different land cover types and different irrigation schedules, with the high ET values in water area, farmland and forest, in contrast to low ET values in grassland and desert. The average ET values for farmland and forest during the studied period were 340 mm and 328 mm, respectively. They were higher than that for grassland of 214 mm and desert of 97 mm. ET variation for farmland was closely related to crop growth, and the highest ET value appeared on June 27^th when both maize and wheat needed a large amount of water. By contrast, the ET values for desert were greatly influenced by the occurrence of precipitation events, as the vegetation was sparse and the most important limitation factor for evapotranspiration in this area was the low soil water content. Besides, the ET values of forest did not change significantly (p&gt;0.05) during this period, with approximately 4 mm/d in sunny days. This study showed that METRIC hold substantial promise to estimate ET values for different land cover types in the middle reach of the Heihe river basin throughout plant growing periods. Besides, the accuracy of ET estimation in the oasis of Heihe middle reach could be improved when the hot extreme pixels in arable land and desert were respectively chosen due to different soil types.
Number of references:39
Main heading:Watersheds
Controlled terms:Arid regions - Evapotranspiration - Extrapolation - Farms - Forestry - Land use - Landforms - Meteorology - Models - Remote sensing  - Soil moisture - Water management - Water supply
Uncontrolled terms:Average relative error - Eddy covariance systems - Heihe river basin - METRIC - SEBAL - Summer - Surface energy balance modeling - Waterresource management
Classification code:403 Urban and Regional Planning and Development - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 446 Waterworks - 446.1 Water Supply Systems - 481.1 Geology - 483.1 Soils and Soil Mechanics - 731.1 Control Systems - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 902.1 Engineering Graphics - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.15.017
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 34>

Accession number:201436062541
Title:Experiment and analysis on path optimization of low-temperature premixed combustion for light-duty vehicle diesel engine
Authors:Yin, Bifeng (1); Wang, Jia (1); He, Jianguang (2); Xu, Yi (2); Jia, Hekun (1)
Author affiliation:(1) School of Automobile and Traffic Engineering, Jiangsu University, Zhenjiang, China; (2) Changchai Company Limited, Changzhou, China
Corresponding author:Yin, Bifeng
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:83-92
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The combustion process of diesel engines has a significant effect on the power, economy, and emission performance of a vehicle. As internal combustion engines tend to be highly effective, energy-saving, and environmentally friendly, all the scholars of the world in this area concentrate on creatively developing the combustion theories and techniques for the oncoming generation of engines in order to break through the emission limits of conventional diesel engines. Aiming at the difficulties of forming the homogeneous charge and organizing the combustion progress for the compact structure of light-duty vehicle diesel engines, the research in this paper was based upon advanced injection combined with high proportion cooling EGR to achieve the low-temperature premixed combustion. Taking advantage of a pressure information acquisition and performance bench test, the effects of fuel injection strategies and intake system parameters on the low-temperature premixed combustion process and pollutants emissions were studied systematically, which explores the effective ways for forming the homogeneous charge and controlling the low-temperature combustion progress so that the theoretical principle of low-temperature premixed combustion techniques for engineering application was built. Based on an in-cylinder pressure information acquisition and performance bench test, the effects of combustion control parameters such as injection timing, injection pressure, intake oxygen concentration, intake temperature, and pilot-injection on a low-temperature premixed combustion process and emission performance were studied. This revealed that taking the advanced injection strategy can prolong the ignition delay period, and improving the fuel-air mixture is the key to reducing the soot emission. Diminishing the intake oxygen concentration can control the temperature of premixed combustion effectively, restrain the production of the NOx emission, and put the ignition phase of a premixed combustion which is too early off, which is beneficial to improving the combustion efficiency and enhancing the fuel economy. Increasing the fuel injection pressure makes the NOx and soot emissions reduced in the low-temperature combustion mode when the load ratios are 10% and 25%, while it brings about the increment of the NOx emission and the decrement of the fuel efficiency in a moderate duty. In the low-temperature combustion mode, the combustion efficiency can be dramatically improved by decreasing the intake temperature and putting off the ignition phase, the in-cylinder temperature can be decreased, and the production of NOx is restrained at the same time. The soot emission can be reduced by raising the intake temperature appropriately when the load ratio is 10%, while intake cooling plays an important role in cutting the soot emission down at the load ratios of 25% and 50%.Multi-injection strategy is an effective method to extend the operating scope of low-temperature combustion and ameliorate the trade-off relationship between the NOx and soot emissions. Pilot injection can reduce the main injection amount, and shorten the ignition delay period of the main injection fuel. As a result, the exothermic phase advances and the peak value of the heat release rate descend so that the soot is successfully restrained. What's more, different injection parameters have different effects on the soot emission. Compared with the original engine, the NOx emissions decreased by 97.8%, 80.7% and 62.1% respectively when the load rates were 10%, 25%, and 50%, and the soot emissions decreased by 76%, 93.9%, and 47.1%, while the brake specific fuel consumptions increased slightly.
Number of references:28
Main heading:Ignition
Controlled terms:Combustion - Diesel engines - Dust - Engines - Exhaust gas recirculation - Fuel economy - Fuel injection - Fuels - Nitrogen oxides - Optimization  - Oxygen - Soot - Temperature
Uncontrolled terms:Early injections - Engineering applications - Experiment and analysis - Fuel injection strategies - Heat Release Rate (HRR) - Information acquisitions - Low-temperature combustion - Premixed combustion
Classification code:451.1 Air Pollution Sources - 521 Fuel Combustion and Flame Research - 521.1 Fuel Combustion - 522 Gas Fuels - 523 Liquid Fuels - 524 Solid Fuels - 612 Engines - 641.1 Thermodynamics - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.15.012
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 35>

Accession number:201436062538
Title:Optimal analysis for cylinder recognition control of electronically controlled diesel engine based on window checking
Authors:Mao, Xiaojian (1); Wei, Xiong (1); Song, Junhua (1); Wang, Junxi (1); Tang, Hangbo (1); Jiang, Zuhua (1)
Author affiliation:(1) School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai, China
Corresponding author:Mao, Xiaojian
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:62-67
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A complaint against the electronic control diesel engine is that it starts "one second slower" than other conventional mechanical pump diesel engines. That is because that on conventional mechanical pump diesel engines, the phase position between the fuel supply sequence of fuel systems and fuel pump cams is fixed in the starting process and there is no need to cylinder recognition. While on the electronic control diesel engine, the controller cannot determine the specific phase of diesel engine until it receives a sufficient number of crank and cam signals, so as to need cylinder recognition. The establishment process of the control timing sequence at the beginning of the starting (cylinder recognition control) is directly determining the duration of the diesel engine starting process. The cylinder recognition control is one of the most basic parts of the electronic control diesel engine management system. In this work, in order to shorten the process of cylinder recognition, a quick and reliable method to determine the precise phase of diesel engine by possibly reducing the crank and cam speed signal is studied. Firstly, according to the firing order of the target diesel engine, speed signal, and the phase of the electronic control system have been designed, using two sets of speed computing devices of cam and crank, not only can shorten the time of cylinder recognition, but also can help to improve the reliability of the control system. And then two methods are proposed in this work, one is judge mode of counting teeth, the other is judge mode of checking window. By analyzing the working principles of the two modes, judge mode of checking window needs less cam and crank signal to cylinder recognition. In the judge mode of counting teeth, at least two cam signals are necessary for cylinder recognition and in the worst case, the cylinder recognition will not succeed until the engine spins two revolutions. While in the judge mode of checking window, the most rapid cylinder recognition only takes 70&deg; crank angle and in the worst situation, the engine only needs to rotate around a little more than that cylinder recognition can succeed. Based on the finite state machine, drive control software of complex driver layer was developed for cylinder recognition control of window observation. Finally, the engine starting test has been done on the engine test bench in order to verify the feasibility of cylinder recognition strategy. By using the cylinder recognition of checking window, the fastest detected two cam teeth can achieve cylinder recognition success in the ideal condition and the cylinder recognition time is 0.3s, in the worse condition the successful cylinder recognition takes 1.3 turn and the time is 0.5s. Besides the starting success rate and time is statistic and compared between the above two modes, by using cylinder recognition of checking window, the success rate of starting has been increased by more than 10%, reaching 100%, and the starting time has been shortened from 1.5s to within 1s. Above experimental results show that the strategy is effective and feasible. The achievement of this strategy not only improves the preferment of electronic control diesel engine in starting condition but also perfects the timing control of electronic control system.
Number of references:20
Main heading:Process control
Controlled terms:Cams - Control systems - Design - Diesel engines - Engine cylinders - Engines - Industrial electronics - Optimization - Servomechanisms - Starting
Uncontrolled terms:Computing devices - Diesel engine management system - Electronic control systems - Electronic controls - Electronically controlled diesel engine - Engine test benches - Recognition control - Recognition strategies
Classification code:408 Structural Design - 601.3 Mechanisms - 612 Engines - 617 Turbines and Steam Turbines - 705 Electric Generators and Motors - 714 Electronic Components and Tubes - 715 Electronic Equipment, General Purpose and Industrial - 716 Telecommunication; Radar, Radio and Television - 731 Automatic Control Principles and Applications - 731.1 Control Systems - 921.5 Optimization Techniques
DOI:10.3969/j.issn.1002-6819.2014.15.009
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 36>

Accession number:201436062536
Title:Numerical simulation of formability of tailor welded blanks for auto door inner panel
Authors:Yu, Tianming (1); Li, Song (2); Lan, Wei (1); Zheng, Lei (3); She, Junwei (1)
Author affiliation:(1) College of Automotive Engineering, Jilin University, Changchun, China; (2) Department of Aviation Theory, Aviation University of Air Force, Changchun, China; (3) R and D Center, China FAW Group Corporation, Changchun, China
Corresponding author:Yu, Tianming
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:46-53
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:In this paper, a new simulation method for weld-line is worked out. Generally the weld modeling uses a rigid way in the weld-line, but for large component such as automobile panel, it makes lower efficiency and even can't finish the calculation. Experience shows that, the fracture will not appear on the weld-line in forming process as long as the weld is qualified. And, in the phase of the component design, what we are concerning more about is the overall formability of the component, therefore a new simulation method for weld-line was brought out: to simplify the handling of the common nodes, which are taken as the common nodes of both sides of weld material. Using this calculation method, grid can be encrypted automatically in the simulation, so that the initial blank does not need to partitioned very small, and the calculation efficiency and stability can be improved.
Number of references:25
Main heading:Computer simulation
Controlled terms:Automobile manufacture - Efficiency - Fracture - Laser beams - Lubrication - Materials handling - Numerical models - Seam welding - Stamping - Welding  - Welds
Uncontrolled terms:Auto door inner panel - Calculation efficiency - Friction coefficients - Simulation parameters - Simulation technologies - Tailor-Welded Blanks - Tailorwelded blanks (TWBs) - Welded seams
Classification code:421 Strength of Building Materials; Mechanical Properties - 535.2 Metal Forming - 538.2 Welding - 538.2.1 Welding Processes - 607.2 Lubrication - 662.1 Automobiles - 691 Bulk Handling and Unit Loads - 723.5 Computer Applications - 744.8 Laser Beam Interactions - 913.1 Production Engineering - 921 Mathematics - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.15.007
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 37>

Accession number:201436062559
Title:Remote sensing detection and spatio-temporal change analysis of wetlands in Xinjiang arid region
Authors:Zhu, Changming (1); Li, Junli (2); Chang, Cun (2); Zhang, Xin (3); Luo, Jiancheng (3)
Author affiliation:(1) Department of Geography and Environment, Jiangsu Normal University, Xuzhou, China; (2) Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China; (3) Institute of Remote Sensing Applications, Chinese Academy of Sciences, Beijing, China
Corresponding author:Li, Junli
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:229-238
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As a part of globle ecosystem, the wetland plays an important role in arid region eco_environment system. The area change of wetland will greatly influence the regional environment. In order to understand the wetlands distribution status, change processes and temporal pattern characteristics in China arid zones under the environment of global change, this paper used multi-source remote sensing data (TM, ETM and CBERS_02) to achieve the arid zone wetlands multi-stage monitoring through object-oriented classification technology and semiautomatic method. Firstly, we used object-oriented technology and hieriarchical classification algorithm, achieved preliminary wetlands infomaiton extraction, and checking the classification accuracy of the primary result by manual visual interpretation. Then, we completed 3 times wetlands distribution mapping on year 2000, 2005 and 2010. On that basis, we analyzed the characteristics of wetland spatial distribution and temporal variation in the past 10 years via land use dynamic change model and the geo-statistical method. The research results show that, 1) Wetlands in Xinjiang arid area has increased by about 10% in the last 10 years on the whole. The total area of wetlands reached to 22 438 km² in 2010 in Xinjiang arid region of China, which increased approximately 2 065 km² compared with the area in 2000. 2) In the spatial distribution, wetlands in the southern and northern Xinjiang are uneven. Wetlands in the southern Xinjiang accounted for about 76% in total wetlands area, and wetlands in the northern Xiangjiang only accounted for 24%. Wetlands Xinjiang arid area mainly distributed in the south of Xinjiang Tarim river basin. And in different basins, wetlands spatial distribution have different characteristics. 3) On wetland types composition, in year 2010, the ratio of river wetland, lake wetland, marsh wetland and artificial wetland are 42.73%, 29.43%, 17.98%, 8.92% and 0.94% respectively. 4) In change process, all type wetlands showed a growing trend in the past 10 years, but the increasing amount and magnitude are different. The variation on different type wetland presents different characteristics and inter-class differences are large. Among them, the dynamic change of marsh wetland and constructed wetland are 2.58 % and 2.43%; The dynamic change of rivers wetlands and lake wetlands are 0.59% and 0.43%. The largest net increased values are marsh wetland and river wetland, which increased by 827.92 km² and 531.86 km² respectively, account for 65.85% of the total increase amount. With the Global warming, rising temperature and increasing precipetation in resent years in Xinjiang district is the main driving force of wetlands increase. And, the human activity intensified the complexity of wetland spatio-temporal change process.
Number of references:33
Main heading:Wetlands
Controlled terms:Arid regions - Global warming - Lakes - Monitoring - Remote sensing - Rivers - Spatial distribution
Uncontrolled terms:Arid area - Classification accuracy - Classification algorithm - Object oriented classification - Object-oriented technology - Regional environments - Spatio-temporal changes - Xinjiang
Classification code:407 Maritime and Port Structures; Rivers and Other Waterways - 407.2 Waterways - 442.2 Land Reclamation - 443 Meteorology - 444 Water Resources - 444.1 Surface Water - 451 Air Pollution - 731.1 Control Systems - 921 Mathematics - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments
DOI:10.3969/j.issn.1002-6819.2014.15.030
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 38>

Accession number:201436062547
Title:Volume replacement methods for measuring soil particle density
Authors:Ma, Yuying (1); Lei, Tingwu (1); Zhuang, Xiaohui (1)
Author affiliation:(1) College of Hydraulic and Civil Engineering, China Agricultural University, Beijing, China; (2) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Yangling, China
Corresponding author:Lei, Tingwu
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:130-139
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:The measurement of soil particle density is of great importance for the study and application of soil and water relationships. This paper proposed a volume replacement method for accurate measurement of soil particle density. Two approaches were used. In the first approach, wet soil samples were used. In wet soil sample method, a wet soil sample of unknown volume and mass was placed into a constant volume container (CVC) and then it was weighted. The CVC was filled up with water to displace the air-filled space in the soil and then the container was weighted to determine the replaced air-filled volume and to determine the volume and mass of initial moisture and soil particles. After that the soil sample was oven-dried to determine the volume and mass of soil particles so that soil particle density (SPD) was calculated. In the other approach, dry soil sample was used. In this method, the soil was completely dried before measuring the mass of soil particles. The soil sample was put into the CVC before it was filled up with water to replace the air-filled volume. The replaced volume was computed from the volume of water used to fill the container. Four soil samples were used for the experiments: a clay loam from Yangling of Shaanxi Province (31.80% clay, 62.80% silt and 5.40% sand particles), a silty loam from Beijing (16.75% clay, 53.00% silt and 30.25% sand particles), a black soil from Jilin Province (12.00% clay, 86.78% silt and 1.22% sand particles) and a red clay from Jiangxi Province (47.60% clay, 45.00% silt and 7.40% sand particles). Soil samples were prepared at 5 initial soil water contents as 10%, 15%, 20%, 25%, 30%. The two approaches discussed above were used to determine the SPD, and then the measured results were compared with the results measured by the pycnometer and volumetric flask methods. Detailed laboratory experiment procedures were made to illustrate the measurement and computational procedures. The results showed that the SPDs of the four soils were 2.6576, 2.6301, 2.6411 and 2.6687 g/cm³ respectively, by using wet sample method, and measured SPDs were 2.6557, 2.6320, 2.6423 and 2.6660 g/cm³ by using dry sample method, when dried for 72 h at 105. Oven-dry of 8 h produced measurement errors in SPDs were 1%-2%, indicating SPDs measured by the volume replacement method with a CVC have high accuracy by extending the drying time. Data points of SPDs measured with volume replacement method by using a CVC was located close to the 1:1 line to indicate the feasibilities of these two proposed methods. Errors in SPDs between wet sample method and dry sample method were less than 0.5%. Generally, in view of measuring accuracy and operating procedures, the newly-suggested methods developed in this study performed better than the conventional methods such as the pycnometer and volumetric flask methods.
Number of references:23
Main heading:Soil surveys
Controlled terms:Bottles - Density (specific gravity) - Experiments - Ovens - Sand - Silt - Soil moisture - Soils - Volume measurement
Uncontrolled terms:Accurate measurement - Computational procedures - Conventional methods - Laboratory experiments - Replacement methods - Study and applications - Volume replacement - Wet sample
Classification code:483.1 Soils and Soil Mechanics - 694.2 Packaging Materials - 822.1 Food Products Plants and Equipment - 901.3 Engineering Research - 931.2 Physical Properties of Gases, Liquids and Solids - 943.2 Mechanical Variables Measurements
DOI:10.3969/j.issn.1002-6819.2014.15.018
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 39>

Accession number:201436062551
Title:Ammoniated straw improving soil structure and winter wheat yield
Authors:Yu, Kun (1); Feng, Hao (1); Wang, Zengli (3); Ding, Dianyuan (1)
Author affiliation:(1) Chinese National Academy of Wate-saving Agriculture in Arid Region, Northwest A and F University, Yangling, China; (2) Institute of Water and Soil Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, China; (3) Wuwei integrated Service Centre on Water Conservancy Technologies of China, Wuwei, China
Corresponding author:Feng, Hao
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:165-173
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:As an important organic resource, straw returning into soil is a most economic and feasible method to improve soil structure and crop yield. Many problems occur in the utilization of straw resources, such as the slow decomposition of straw and the competition of nitrogen between straw and crop when the straw is applied into soil, thereby negatively affecting the crop yield. These problems can be affected by straw-incorporation methods, and an appropriate method may result in few problems. Therefore, this study aimed to select an efficient straw incorporation method to improve soil structure and increase crop yield in semi-arid region of Shaanxi China. To achieve this goal, a 2-year field experiment was carried out in the year of 2011- 2013. Summer maize straw was used. Two control treatments included long straw returning by covering soil (CK1), long straw plowed into soil (CK2). Four straw treatments were long-ammoniated straw plowed into soil (CN), powdered-ammoniated straw plowed into soil (FN), long-ammoniated straw mixed with inorganic soil amendment (calcium sulfate) plowed into soil (CNT) and powdered-ammoniated straw mixed with inorganic soil amendment (calcium sulfate) plowed into soil (FNT). The soil bulk density, total porosity, water stable aggregates, mean weight diameter (MWD), geometric mean diameter (GMD), and fractional dimension of soil aggregates were determined before experiment in 2010. Winter wheat was planted after straw returning. After harvesting winter wheat and measuring its yield, we collected soil samples at the depth of 0-30 cm and determined the soil structure-related indicators as above. The results showed that compared with CK1 and CK2, the treatment FN in the plough layer (0-15 cm) significantly (P&lt;0.05) reduced the soil bulk density by 6.30% and 7.03%, respectively, and significantly (P&lt;0.05) increased soil porosity by 5.07% and 6.40%, respectively. The treatment of powdered-ammoniated straw had no significant effect on the soil bulk density and porosity at the &gt;15-30 cm. In 0-15 cm soil layer, the application of powdered-ammoniated straw (P&lt;0.05) increased the content of soil aggregates (&gt;0.25 mm), significantly (P&lt;0.05) decreased soil fractal dimension, and improved MWD and GMD, improving the stability of soil structure. The correlation coefficient between grain yield and grain number, efficient panicle, 1000-grain weight, and above-ground biomass was 0.30 (P&gt;0.05), 0.76 (P&lt;0.01), -0.89 (P&lt;0.01) and 0.88 (P&lt;0.01), respectively. It indicated that the increase of its efficient panicle or aboveground biomass may primarily contribute to the increase in the yield of winter wheat. Among all the treatments, the treatment FNT had the most significant effect on increasing the yield of winter wheat. Its yield was increased by 11.12% (2011-2012) and 17.85% (2012-2013) compared with the CK1, and by 7.39% (2011-2012) and 16.59% (2012-2013) compared with the FN. Therefore, the treatment FNT was the best straw-incorporation method in this study. The results above could provide valuable information for selecting efficient straw-incorporation method to improve soil structure and crop yield in semi-arid regions of China.
Number of references:28
Main heading:Soils
Controlled terms:Aggregates - Arid regions - Crops - Driers (materials) - Fractal dimension - Porosity - Powders - Straw - Structure (composition) - Well drilling
Uncontrolled terms:Above ground biomass - Ammoniation - Correlation coefficient - Geometric mean diameters - Soil bulk density - Straw incorporations - Water stable aggregates - Yield
Classification code:406 Highway Engineering - 443 Meteorology - 444 Water Resources - 446.1 Water Supply Systems - 483.1 Soils and Soil Mechanics - 536 Powder Metallurgy - 803 Chemical Agents and Basic Industrial Chemicals - 804 Chemical Products Generally - 821.4 Agricultural Products - 821.5 Agricultural Wastes - 921 Mathematics - 931.2 Physical Properties of Gases, Liquids and Solids - 951 Materials Science
DOI:10.3969/j.issn.1002-6819.2014.15.022
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 40>

Accession number:201436062530
Title:Analysis and experiment on working performance of disc coulter for no-tillage seeder
Authors:Bai, Xiaohu (1); Lin, Jing (1); L, Changyi (1); Hu, Yanqing (1)
Author affiliation:(1) College of Engineering, Shenyang Agricultural University, Shenyang, China
Corresponding author:Lin, Jing
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:1-9
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:Compared with traditional tillage, conservational tillage-also known as zero tillage can effectively prevent soil from wind and water erosion, resist spring drought, prevent sandstorm, increase crop yield, and save cost. No-tillage planter is an important agricultural implement for conservational tillage. In northeast China where ridge culture is the primary planting mode for maize production, the highly effective stubble-cutting device is required because the soil in this region is often covered by hard stubble and a small amount of stalks. Stubble-cutting device is one of the key components affecting performance of no-tillage planter. Two kinds of stubble-cutting device are commonly used, including power-driven device and passive one. Power-driven device can smash stubble and create good seedbed, but is also associated with soil disturbance, high power consumption and blade wear. Passive device of simple structures consumes less energy and only causes slight soil disturbance. Among them, rolling types of disc stubble-cutting coulters can easily cut through stubble under the soil surface without throwing stubbles out of the soil, so it is suitable for application in Northeast China. There are few studies on cutting velocity and working resistance of dis coulters. However, an understanding of cutting velocity and working resistance of dis coulters is necessary for design and application of dis coulters. Therefore, this study investigated the cutting velocity under the condition that coulters slides occurred, and working resistance in vertical direction as well as tractive resistance by kinematics and force analysis, the influence of auxiliary weight and unit working speed on stubble-cutting depth of three disc coulters (plain, wavy, and turbo) in single factor field experiments, and the influence of disc coulter type, auxiliary weight and unit working speed on tractor resistance in an orthogonal field experiment of three factors and three levels. Both theoretical analysis and field tests showed that the coulter slippage had negative effect on the cutting velocity during the stubble-cutting process, which suggested reducing the coulter slippage to the greatest extent in the application of dis coulters. The tractor resistance of coulters changed slightly during the process of cutting soil in an increasing and then decreasing trend during the process of stubble cutting. The cutting depth of the three coulters increased with increasing auxiliary weight. When the auxiliary weight was less than 48 kg, the cutting stubble depth of plain coulter was largest, followed by the turbo coulter as well as the wave coulter. In practice, stubble under the ground must be totally cut through in order to make sure that no-tillage planter could be in good operation. To obtain a cutting depth of 80 mm or above, the minimum auxiliary weight of the plain, wavy and turbo disc coulter was required to be 48, 72 and 60 kg respectively. Since the total weight of force-measuring device and general frame was 100 kg, the down pressure acted on the plain, wavy and turbo disc coulter should be not less than 148, 172 and 160 kg in order to acquire enough cutting depth in designing no-tillage planter. The tractor resistance increased with increasing unit working speed, and could be affected by auxiliary weight &gt; unit working speed &gt; coulter types. With minimum auxiliary weight, the least tractor resistance of plain coulter, turbo coulter and wave coulter was 2.52, 2.65 and 2.75 kN, respectively. This study provided valuable information for the design and application of disc coulter and no-tillage planter.
Number of references:33
Main heading:Disks (machine components)
Controlled terms:Agricultural implements - Agricultural machinery - Cultivation - Design - Mechanical engineering - Soils - Storms - Tractors (agricultural) - Tractors (truck) - Velocity
Uncontrolled terms:Design and application - Disc coulter - High power consumption - No tillage - No-tillage planter - No-tillage seeders - Vertical direction - Working performance
Classification code:408 Structural Design - 443.3 Precipitation - 483.1 Soils and Soil Mechanics - 601.2 Machine Components - 608 Mechanical Engineering, General - 663.1 Heavy Duty Motor Vehicles - 821.1 Agricultural Machinery and Equipment - 821.3 Agricultural Methods - 931.1 Mechanics
DOI:10.3969/j.issn.1002-6819.2014.15.001
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 41>

Accession number:201436062534
Title:Statics analysis of dragonfly wing based on finite element model
Authors:Zhao, Yanru (1); Wang, Dongsheng (1); Tong, Jin (2); Sun, Jiyu (2); Zhang, Jin (3)
Author affiliation:(1) School of Mechanical and Power Engineering, Henan Polytechnic University, Jiaozuo, China; (2) College of Biological and Agricultural Engineering, Jilin University, Changchun, China; (3) United Automotive Electronic Systems Co., Ltd, Shanghai, China
Corresponding author:Zhao, Yanru
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:33-38
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:A dragonfly can hover, flap its wings for flight and fly vertically for a short distance. The membranous wings of a dragonfly have a high load-bearing capacity for static and dynamic load during flight. The mass of the wings of a dragonfly is only 1%-2% of its whole body but the wings can stabilize its body. The statics properties of biomimetic models were researched. The finite element software ANSYS was used to simulate the dragonfly wing. The veins were simulated by pipe20 with two nodes and the membranes by shell43 with four nodes. The influence of geometrical nonlinearity was taken into account but material nonlinearity. The models were assumed in the elastic range. The three-dimensional model of the dragonfly wing was reconstructed using reverse engineering software Imageware. The veins of dragonfly wing were drawn with AutoCAD and the membranes were added with ANSYS. The finite element models imitating the dragonfly wing were established by using free meshing. The finite element models of the dragonfly wing were simulated with structural statics. The deformation, the stress and the strain of the models under loads were analyzed respectively. The loads include the uniform load, the bending moment and the torque. Under the uniform load, the deformation of the finite element model imitating a dragonfly wing is very small, and increases gradually from the base to the wing tip. The base of the model bears heavy stress, the middle parts smaller, and the wing tip the least. The strain shows a radial pattern along the longitudinal veins, and reduces gradually from the base to the wing tip of the model. Under the bending moment, the deformation and the rotation angle around y axis increase gradually from the base to the wing tip of the model. The heavy stress and strain are mainly concentrated on the base of the model. The small stress and strain are acted on the middle parts and the wing tip. The distribution trend of the stress and strain is in substantial agreement. Under the torque, the finite element model imitating a dragonfly wing deforms only a little as a whole. The heavy deformation is mainly concentrated on the leading edges and the rear edges of the model. The smaller deformation is acted on the middle parts and the least deformation on the base. The maximum stress and strain occur at the middle parts of the model. The minimum stress and strain occur at the base of the model. The dragonfly wing is a two-dimensional truss structure with excellent rigidity. The dragonfly wing deforms only a little under loads. It is shown that the grid structures of the dragonfly wing deforming together at the boundaries of veins and membranes have excellent integrity. The understanding of dragonfly wings' characteristics provides some reference for improving the properties of two-dimensional composite materials through biomimetic designs.
Number of references:24
Main heading:Finite element method
Controlled terms:Bending moments - Biomimetics - Bionics - Computer aided design - Deformation - Dynamic loads - Reverse engineering - Rigid wings - Static analysis
Uncontrolled terms:Dragonfly wings - Finite element software - Geometrical non-linearity - Load-bearing capacity - Material non-linearity - Static and dynamic loads - Three-dimensional model - Uniform loads
Classification code:408.1 Structural Design, General - 421 Strength of Building Materials; Mechanical Properties - 422 Strength of Building Materials; Test Equipment and Methods - 461.9 Biology - 652.1 Aircraft, General - 723 Computer Software, Data Handling and Applications - 723.5 Computer Applications - 731.1 Control Systems - 921.6 Numerical Methods
DOI:10.3969/j.issn.1002-6819.2014.15.005
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.

<RECORD 42>

Accession number:201436062560
Title:Research on fractal dimension of vegetation cover based on normalized difference vegetation index in watershed scale
Authors:Li, Binbin (1); Li, Zhanbin (1); Yu, Tao (1); Li, Peng (1)
Author affiliation:(1) Key Lab of Northwest Water Resources and Environment Ecology of MOE at XAUT, Xi'an University of Technology, Xi'an, China; (2) Beijing Soil Conservation and Ecology Engineering Consulting Company Limited, Beijing, China; (3) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Sciences and Ministry of Water Resources, Yangling, China
Corresponding author:Li, Zhanbin
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:30
Issue:15
Issue date:August 1, 2014
Publication year:2014
Pages:239-247
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering
Abstract:It is a critical issue to quantify and characterize the complexity of the spatial distribution of vegetation cover when studying the effects of vegetation cover on material migration processes of the earth's surface at the watershed scale. Fractal theory, known as "geometry of nature", is the frequently-used tool for quantitative research on the distribution and complexity of vegetation at different scales. But fewer researches of the spatial distribution of vegetation with fractal theory at the pixel scale are reported. The objective of this work was to establish the method of using NDVI values and fractional Brownian motion (FBM) theory to describe the complexity of the spatial distribution of vegetation cover. Firstly, the spatial distribution pattern of pixel NDVI, which had the similar data structure with digital elevation model, was produced by using geographic information system (GIS) and the pixel NDVI values in this paper. Secondly, moving window method was developed with GIS software, and then it was used to measure the increments of each pixel NDVI in the watershed. Last, fractal dimension of vegetation cover based on the spatial distribution pattern of NDVI values at the pixel scale was calculated with FBM theory. Taking Dali River Basin as an example, it was divided into four orders according to the watershed area. The watershed area declined five times per order. FBM fractal dimension of watershed vegetation cover based on pixel NDVI values was calculated under different watershed scales. The results showed that spatial distribution of watershed vegetation cover on the watershed had the significantly (P&lt;0.01) statistical self-similarity, which can be characterized with FBM theory. FBM fractal dimension for watershed vegetation cover was between 2.5 to 3.0, and the value closer to 2.5 demonstrated the more complex the spatial distribution of vegetation cover. FBM fractal dimension of vegetation cover ranged from 2.695 to 2.817 within the Dali River Basin at different area scales. It increased with power function as the watershed area increased, and the increase was smaller after a certain size with the drainage area increasing. FBM fractal dimension of vegetation cover tended to be stable and was infinitely closer to FBM fractal dimension of the entire watershed. These results indicated that FBM fractal dimension of vegetation cover was affected by the watershed scale. FBM fractal dimension of vegetation cover had no direct relationship with the mean NDVI of watershed and coefficient variation of pixel NDVI, but it was significantly (P&lt;0.01) negatively correlated to the numbers of different NDVI per square kilometer at different watershed. FBM fractal dimension of watershed vegetation cover overcame the effect of the singular value of NDVI on quantifying and characterizing the complexity of the spatial distribution of vegetation cover and remedied the defect of NDVI diversity (such as information entropy) and other indices characterizing the complexity of vegetation coverage. Compared with the traditional indices of quantifying and characterizing the complexity of vegetation cover, it had a wider application in hydrology, soil erosion model when studying on the relationship between vegetation and material migration at the watershed scale.
Number of references:20
Main heading:Vegetation
Controlled terms:Algorithms - Fractal dimension - Geographic information systems - Pixels - Spatial distribution - Watersheds
Uncontrolled terms:Digital elevation model - Fractional brownian motion - Moving window methods - Normalized difference vegetation index - Quantitative research - Soil erosion modeling - Spatial distribution patterns - Vegetation cover
Classification code:444.1 Surface Water - 723.3 Database Systems - 723.5 Computer Applications - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2014.15.031
Database:Compendex
Compilation and indexing terms, Copyright 2014 Elsevier Inc.