<RECORD 1>

Accession number:20132516429369
Title:Nitrogen removal increased in anammox reactor by effluent recirculation
Authors:Li, Xiang (1); Huang, Yong (1); Zhou, Cheng (1); Yuan, Yi (1); Li, Dapeng (1); Liu, Fuxin (1)
Author affiliation:(1) School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 2150l1, China; (2) College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
Corresponding author:Li, X.(lixiang@mail.usts.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:178-183
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The anaerobic ammonia oxidation (Anammox) process, which involves the simultaneous conversion of ammonium and nitrite into nitrogen gas under an anaerobic condition, has recently been attracting attention. This is because it consumes less energy, produces less sludge, and requires fewer carbon sources for denitrification as compared to the conventional nitrification and denitrification process. However, the inhibition phenomenon was always found in an Anammox reactor when there are High concentration of NH<inf>4</inf>-N and NO<inf>2</inf>^--N feeding. A study was made of the effect of adding recirculation in an Anammox reactor to alleviate the high substrate concentration inhibition. The characteristics of nitrogen removal were investigated in two up-flow reactors by adding effluent recirculation and inoculating Anammox sludge under high substrate concentration. After 116 days running in the reactor 1 with effluent recirculation, the results showed that the effluent concentrations of NH<inf>4</inf>-N and NO<inf>2</inf>^--N only were 44 and 60 mg/L and nitrogen removal load was 7.87 kg N/(m³&middotd), when the influent concentrations of NH<inf>4</inf>-N and NO<inf>2</inf>^--N were up from 100 and 130 mg/L to 602 and 782 mg/L respectively. The transformation ratio of NO<inf>2</inf>^--N removal, NO<inf>3</inf>^--N production and NH<inf>4</inf>-N removal were 1.303/0.24/1. On the other hand, after 67 days running in reactor 2 without effluent recirculation, the effluent concentrations of NH<inf>4</inf>-N and NO<inf>2</inf>^--N were 174 mg/L and 253 mg/L, and nitrogen removal load was kept at 4.31 kg N/(m³&middotd), when the influent concentrations of NH<inf>4</inf>-N and NO<inf>2</inf>^--N were up from 100 and 130 mg/L to 456 and 600 mg/L respectively. The transformation ratio of NO<inf>2</inf>^--N removal, NO<inf>3</inf>^--N production and NH<inf>4</inf>-N removal were 1.303/0.21/1. It indicates that effluent recirculation had a high dilution function and was helpful in avoiding the inhibition effect of a high substrate concentration on the activity of Anammox. It had no effect on effluent recirculation on NH<inf>4</inf>-N and NO<inf>2</inf>^--N transformation in Anammox process. The granular size of sludge was mainly 1.25-2 mm in reactor 1, while in reactor 2, the granular size was 0.9-1.6 mm, showing that, effluent circulation increased the liquid up-flow velocity and improved the production of Anammox sludge. Therefore, effluent recirculation was beneficial to enhancing the nitrogen removal under high substrate concentration in a Anammox reactor.
Number of references:28
Main heading:Wastewater treatment
Controlled terms:Denitrification - Nitrogen oxides - Nitrogen removal - Substrates
Uncontrolled terms:ANAMMOX - Effluent concentrations - Effluent recirculation - High substrate concentrations - Influent concentrations - Liquid up-flow velocity - Nitrification and denitrification - Refluence
Classification code:452.4 Industrial Wastes Treatment and Disposal - 461 Bioengineering and Biology - 801 Chemistry - 802.2 Chemical Reactions - 804.2 Inorganic Compounds
DOI:10.3969/j.issn.1002-6819.2013.09.023
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 2>

Accession number:20132516429361
Title:Covering farming pattern to improve soil physical properties and crop yield in wheat-maize cropping system
Authors:Zhao, Hongxiang (1); Chi, Shuyun (1); Ning, Tangyuan (1); Tian, Shenzhong (1); Wang, Bingwen (1); Li, Zengjia (1)
Author affiliation:(1) Agronomy College of Shandong Agricultural University, State Key Laboratory of Crop Biology, National Engineering Laboratory for Efficient Utilization of Soil and Fertilizer Resources, Tai'an 271018, China
Corresponding author:Chi, S.(chishujun1955@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:113-122
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Soil physical properties and crop productivity are general affected by different management methods of farmland, such as different tillage systems and crop straw managements. The objective of this study were to measure physical properties of soil including soil water content, soil water storage, soil bulk density and soil porosity (capillary porosity and non-capillary porosity) under a long-term tillage and straw management experiment system in the North China Plain, and the crop productivity of a wheat-maize cropping system was also analyzed (2010-2012). The study was assessed on 10 year field study with a split-plot design, which involved two tillage methods of conventional tillage (C) and zero tillage (Z) and four levels of straw utilization systems at straw returning (P), stubble returning of 1m height (-1), stubble returning of 0.5 m height (-0.5) and straw removal (A). The innovation of this study investigated effects of 4 different stubble heights returning on soil physical properties and crop yields. The result showed that, the soil water content in the 0-40 cm soil layer under treatments of conventional tillage and zero tillage increased with the amounts of straw returning increasing, so straw returning could increase the soil water content, Z-0.5 was more than 15.95% to AZ. In comparison to the conventional tillage, no tillage method combination with straw could improve the soil moisture, so zero tillage could improve the soil water content. In 0-40 cm soil layer, amounts of straw returning affected variation of soil water storage in the two stages, in the planting stage of wheat, soil water storage under treatments of conventional tillage and zero tillage gradually reduced with the amounts of straw returning increasing, but in the maturating stage of wheat, soil water storage under treatments of conventional tillage and zero tillage gradually increased with the amounts of straw returning increasing. In the planting stage of wheat, tillage methods could significantly affected soil bulk density, the treatment of stubble 1 meter returning had the lower soil bulk density (p&lt;0.05). However, soil bulk density could self-increasing with the times, eventually there was no significant difference of soil bulk density under treatments of conventional tillage and zero tillage in the maturating stage of wheat. Straw returning also increased the soil porosity, reduced the ratio of capillary porosity and non-capillary porosity in the planting stage of wheat. Zero tillage treatment without straw returning reduced wheat and maize yields, but the zero tillage method combination with straw could increase total yields of wheat and maize, and the best treatment to increase yields was 1 m stubble returning treatment, it increased 22.44% than zero tillage without straw returning. Therefore, the treatment of stubble 1 m returning had conducive to improve soil physical properties and crop productivity.
Number of references:36
Main heading:Agricultural machinery
Controlled terms:Crops - Physical properties - Porosity - Productivity - Soil moisture - Soils - Storage management
Uncontrolled terms:Amounts of straw returning - Crop yield - Soil bulk density - Soil Porosity - Tillage methods
Classification code:483.1 Soils and Soil Mechanics - 723.3 Database Systems - 821.1 Agricultural Machinery and Equipment - 821.4 Agricultural Products - 913.1 Production Engineering - 931.2 Physical Properties of Gases, Liquids and Solids
DOI:10.3969/j.issn.1002-6819.2013.09.015
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 3>

Accession number:20132516429377
Title:Analysis on dynamic evolution and driving force of land-use landscape in Hongmenchuan basin
Authors:Zhao, Yang (1); Yu, Xinxiao (1); Jia, Jianbo (1); Liu, Xuhui (1)
Author affiliation:(1) School of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China
Corresponding author:Yu, X.(yuxinxiao111@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:239-248
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Analysis of the land use and land cover changes (LUCC) and its driving factors in water conservation zones is essential for the development of sustainable water resource strategies. Miyun Reservoir is the most important drinking water source for Beijing Municipality, the capital of China with a population of more than 20 million.In recent decades, the inflow to the reservoir has shown a decreasing trend, which has seriously threatened the security of water use in Beijing. According to researches, LUCC is generally assumed to be responsible for changes in water yield of catchments. In order to explore the evolution process and driving factors of landscape changes in water source protection zones of the metropolitan area, Hongmenchuan watershed located in Miyun County was selected as the research object. The characteristics and the dynamic evolution of landscape patterns during 1990 to 2005 were analyzed by applying landscape ecological method and Markov model on the basis of the land use information from remote sensing. Combined with Grey forecast model of GM (1, 1) and the principal components analysis, the driving force of landscape changes were discussed from three aspects of the socio-economic, the natural conditions and regional policy and the population, respectively. Brief conclusions can be drawn as follows: major LULC changes in the period from 1990 to 2005 include declines of water area, and major increases in urban area. Moreover, the rapid reduction of water area and the continued increase of construction land were the most obvious features of the landscape changes in Hongmenchuan watershed during the period of 1990-2005. Changes of comprehensive dynamic degree of land use in different periods indicated that land use change rate showed an accelerated increasing trend. Landscape fragmentation increased significantly and patches distribution of various landscape types tend to be gathered, which lead to the patches shape more complicated. Based on the predictable results, the water area will be reduced by 67.5% in 2020 and inevitably exacerbate the contradictions of water use in the watershed. Although the forests cover falls to 73.81%, it still meets the appropriate forest coverage for water conservation. Changes of precipitation were the main reason for the change of water area, and regional policy was the basic reason for the changes of forest area and forest structure. Human factors may be the major driving force of the increase of construction land and the conversion of unused land, water area to farmland. The results can provide important benchmarks for assessing the significance of human activities, regional policy on the regional land use and land cover change, and also finally put forward a scientific reference for sustainable utilization, development and management of land resource in this region.
Number of references:31
Main heading:Reservoirs (water)
Controlled terms:Catchments - Economics - Farms - Forestry - Geomorphology - Land use - Landforms - Markov processes - Models - Principal component analysis  - Surface waters - System theory - Water conservation - Water supply - Watersheds
Uncontrolled terms:GM (1 , 1) - Land use and land cover change - Landscape index - Management of land resources - Markov model - Principal components analysis - Returning farmland to forest projects - Sustainable water resources
Classification code:971 Social Sciences - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 821.0 Woodlands and Forestry - 902.1 Engineering Graphics - 922.1 Probability Theory - 922.2 Mathematical Statistics - 961 Systems Science - 481.1.1 Geomorphology - 446.1 Water Supply Systems - 444.1 Surface Water - 444 Water Resources - 441.2 Reservoirs - 403 Urban and Regional Planning and Development - 481.1 Geology
DOI:10.3969/j.issn.1002-6819.2013.09.031
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 4>

Accession number:20132516429353
Title:Emission characteristics of double swirl combustion system in diesel engine
Authors:Sun, Baigang (1); Xie, Jun (1); Chai, Guoying (2); Zhao, Jianhui (1); Li, Xiangrong (1)
Author affiliation:(1) School of Mechanical Engineering, Beijing Institute of Technology, Beijing 100081, China; (2) China North Engine Research Institute, Tianjin 300400, China
Corresponding author:Sun, B.(sunbg@bit.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:48-54
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The emission of diesel engines, to some extent, restricted the development of the diesel engine industry. Due to the importance of the combustion system of the diesel engine, there is a growing concern to reduce harmful emissions by improving the combustion system. Many factors influence on the engine performance and emissions, but the shape of the combustion chamber of direct injection diesel engine has a very important influence on the combustion process and the generation of harmful emissions. For Double Swirl Combustion System research focuses on reducing the detonation pressure, fuel consumption and the numerical simulation of spray mixing mechanism, and its emission characteristics of a few. To take Test and CFD simulation method to explore the fuel injection system, fuel injection timing, nozzle diameter, spray angle and swirl ratio to influence of emission characteristics of double swirl combustion system (DSCS). The results show that: with the increase of the fuel injection advance angle and the nozzle diameter decreases, NO<inf>x</inf> production increases, soot formation was reduced. Because the ignition delay period of cylinder mixture was increased with the increase in injection advance angle, the oil and gas mixing quality is improved with the increase in the ignition delay period, thus making the cylinder to an increase in the maximum combustion temperature. The temperature of the main factors of NO<inf>x</inf> generated, so NO<inf>x</inf> formation increases with the increase in injection advance angle. The reasons for the reduction of soot are the increase of the ignition delay period such that the cylinder fuel mixture better, reducing soot generation. With the increase in the diameter of the spray hole, the cylinder fuel quality deterioration, resulting in insufficient combustion produce soot emissions. With the increases in the angle of spray, soot formation was reduced, the amount of NO<inf>x</inf> first increases and then decreased. Excessively large spray angle and arc ridge, resulting the deterioration of the quality of the fuel mixture, and the high temperature region is concentrated in the top of the combustion chamber, the air of the entire combustion chamber is not fully utilized, the lack of oxygen leads to a reduction in the amount of NO<inf>x</inf> generated. Soot formation is due to the local presence of fuel too thick. The swirl ratio and arc ridge matching directly affect the fuel atomization, mixing and combustion process of DSCS, smaller swirl ratio and arc ridge matching should be used in order to reduce the emissions of harmful pollutions.
Number of references:25
Main heading:Diesel engines
Controlled terms:Combustion chambers - Computational fluid dynamics - Computer simulation - Cylinders (shapes) - Deterioration - Dust - Experiments - Fuel injection - Fuels - Ignition  - Mixing - Mixtures - Reduction - Soot - Spray nozzles
Uncontrolled terms:Combustion systems - Direct injection diesel engines - Emission characteristics - Fuel injection advance angles - Fuel injection systems - Injection advance angles - Maximum combustion temperature - Swirl ratio
Classification code:901.3 Engineering Research - 612.2 Diesel Engines - 631.1 Fluid Flow, General - 654.2 Rocket Engines - 723.5 Computer Applications - 802.2 Chemical Reactions - 802.3 Chemical Operations - 524 Solid Fuels - 522 Gas Fuels - 521.1 Fuel Combustion - 521 Fuel Combustion and Flame Research - 451.1 Air Pollution Sources - 408.2 Structural Members and Shapes - 523 Liquid Fuels
DOI:10.3969/j.issn.1002-6819.2013.09.007
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 5>

Accession number:20132516429360
Title:Evaluation of yield increasing potential by irrigation of spring maize in Heilongjiang province based on Hybrid-Maize model
Authors:Hou, Peng (1); Chen, Xinping (1); Cui, Zhenling (1); Wang, Wei (3); Wang, Li'na (4); Tang, Jinfu (5); Zhang, Fusuo (1)
Author affiliation:(1) Center for Resources, Environment and Food Security, China Agricultural University, Beijing 100193, China; (2) Institute of Crop Sciences, Chinese Academy of Agricultural Sciences, Beijing 100081, China; (3) Agricultural Department of General Bureau of State Farms of Heilongjiang Province, Harbin 150036, China; (4) Qixing Farm of General Bureau of State Farms of Heilongjiang Province, Jiansanjiang 156300, China; (5) 850 Farm of General Bureau of State Farms of Heilongjiang Province, Hulin 158422, China
Corresponding author:Chen, X.(chenxp@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:103-112
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The yield increasing potential of irrigation was the basis of the construction of irrigation facilities on a regional scale. In this study, the maize yield increasing potential of irrigation in Heilongjiang province was evaluated using a process-based model "Hybrid-Maize." Through two field experiments in Qixing and 850 farms in Heilongjiang, the Hybrid-Maize model was verified and showed a good simulation in both irrigation and rain-fed conditions. To study the maize yield increasing potential of irrigation (the yield gap between irrigation and rainfed yield potential) in Heilongjiang province, modeling work combined with agronomic practice (cultivar, plant density and growth durations) and historical meteorological data was conducted. Modeling results showed that the maize yield increasing potential by irrigation was highest at the first accumulated temperature zone and was low at the third, fourth and fifth accumulated temperature zones. The west representative sites of the first and second accumulated temperature zones showed higher yield increasing potential of irrigation than the east representative sites. Regional modeling results showed that, under condition of irrigation, there was the highest yield potential with more than 15000 kg/hm² in the southwest region of Heilongjiang province, and under condition of rain-fed, there was the highest yield potential with 14000-14799 kg/hm² in the east region of Heilongjiang province. From the southwest to the east and north, the yield increasing potential of irrigation showed a declining trend from more than 1600 kg/hm² to less than 300 kg/hm². When the mean growing season and annual precipitations were less than 350 mm and 430 mm respectively, the variance of the yield increasing potential of irrigation was the largest. In conclusion, we suggest that the south-west area in Heilongjiang province, where the mean growing season and annual precipitations were less than 350 mm and 430 mm in the first and second accumulated temperature zones, should be the priority area for the construction of irrigation facilities. The study can provide references for reasonable irrigation facilities construction in Heilongjiang.
Number of references:32
Main heading:Irrigation
Controlled terms:Computer simulation - Meteorology - Models - Rain
Uncontrolled terms:Accumulated temperatures - Agronomic practices - Annual precipitation - Heilongjiang - Maize - Meteorological data - Process-based models - Yield-increasing
Classification code:443 Meteorology - 443.3 Precipitation - 723.5 Computer Applications - 821.3 Agricultural Methods - 902.1 Engineering Graphics
DOI:10.3969/j.issn.1002-6819.2013.09.014
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 6>

Accession number:20132516429381
Title:Optimization of compound color fixative without sulfur during sweet potato flour processing
Authors:He, Jiwen (1); Cheng, Li (1); Hong, Yan (1); Gu, Zhengbiao (1); Li, Zhaofeng (1)
Author affiliation:(1) State Key Laboratory of Food Science and Technology, Wuxi 214122, China; (2) School of Food Science and Technology, Jiangnan University, Wuxi 214122, China
Corresponding author:Hong, Y.
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:275-284
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Sweet potatoes are highly nutritious vegetables that are rich in calories and biologically active phytochemicals such as &beta;-carotene, polyphenols, ascorbic acid and dietary fiber. While the sweet potato is the seventh most important food crop grown in around 111 countries, China contributes about 80% of the world's production of sweet potatoes, where the roots are used as food, animal feed and as a raw material for starch and noodle manufacture. Sweet potatoes are highly perishable and difficult to store. In developing countries, there are many problems related to storage and transportation of the raw sweet potatoes. Sweet potato flour is regarded as the ideal product to solve the storage and transportation problem which could expand its utilization in various areas of food production as well. But using sweet potato flour for product development is hindered by the discoloration from enzymatic browning. Using a color fixative is the most convenient and effective method, the commonly used color fixatives are Critic acid, Disodium stannous citrate, Phytic acid, Sodium sulfite, Ascorbic acid and so on. Among these chemicals, Sodium sulfite is the most effective one, but using Sodium sulfite could lead to SO<inf>2</inf> residue which may threat human health seriously, earlier in 1986, the FDA had banned its use in fresh fruit and vegetables. Therefore we urgently need to develop a safe and efficient color fixative without sulfur to reach the purpose of improving the food taste, nutrition and safety. Because of its more comprehensive and efficient color protecting effect, compound color fixative was regarded as the feasible scheme to take the place of Sodium sulfite. In this paper, Critic acid, Disodium stannous citrate, Phytic acid, Sodium sulfite and Ascorbic acid were selected as the color fixative to inspect their effects on the L^* value of the sweet potato flour. Critic acid and ascorbic acid were selected as the preferred color fixative. Through regression orthogonal design, we confirmed that a better quality of sweet potato flour could be obtained through soaking the 10mm slices in the compound color fixative that contains a mass fraction of 0.3% critic acid and a mass fraction of 0.1% ascorbic acid for 30 min. At the same that the mass fraction was (0.4%), the L^* value of the sweet potato flour treated with the compound color fixative could reach 90.58, which was similar with the product treated with Sodium sulfite, the polyphenol oxidase inhibition ratio could also reach 88.13%, higher than others treated with single color fixative. Finally, there was a preliminary exploration of the browning inhibition mechanism of the compound color fixative. The results showed that the addition of critic acid could enhance the thermal stability of ascorbic acid. The absorption peak of enzymatic browning products of polyphenol oxidase with a compound color fixative was significantly weakened at 410 nm in UV spectrophotometric, which indicated that compound color fixative could effectively inhibit the enzymatic browning reactions to reduce the formation of precipitation recognized as the browning products. Circular dichroism showed that the compound color fixative might reduce polyphenol oxidase activity by changing its molecular conformation. The amount of &alpha;-helix in the secondary structure of polyphenol oxidase decreased as opposed to the increase of &beta;-sheet. This study can provide references for the use of a compound color fixative without sulfur during sweet potato flour processing.
Number of references:27
Main heading:Food storage
Controlled terms:Ascorbic acid - Chemical reactions - Color - Developing countries - Health risks - Manufacture - Mechanisms - Optimization - Product development - Sodium  - Sulfur - Sulfur dioxide - Vegetables
Uncontrolled terms:Compound color fixative - Fresh fruit and vegetables - Inhibition mechanisms - Molecular conformation - Secondary structures - Storage and transportations - Sweet potato flour - UV spectrophotometric
Classification code:913.1 Production Engineering - 901.4 Impact of Technology on Society - 822.1 Food Products Plants and Equipment - 821.4 Agricultural Products - 804 Chemical Products Generally - 921.5 Optimization Techniques - 802.2 Chemical Reactions - 601.3 Mechanisms - 549.1 Alkali Metals - 537.1 Heat Treatment Processes - 461.7 Health Care - 741.1 Light/Optics
DOI:10.3969/j.issn.1002-6819.2013.09.035
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 7>

Accession number:20132516429370
Title:Research and application of high-efficiency eco-engineering rural sewage treatment system
Authors:Liu, Xiaolu (1); Niu, Hongbin (2); Yan, Hai (1); Ding, Zhan (3); Lu, Fenglan (4); Ma, Xiaoyi (5); Yang, Liuqing (1); Liu, Yongzhi (1)
Author affiliation:(1) University of Science and Technology Beijing, School of Chemistry and Biological Engineering, Beijing 100083, China; (2) He'nan Agricultural University, National Engineering Technology Research Center for Wheat, Zhengzhou 450002, China; (3) Unit 63956, Beijing 100093, China; (4) The Beijing Debang Energy and Environment Technology Limited Liability Company, Beijing 100016, China; (5) Chongqing Kaixian People's Government, Chongqing 405400, China
Corresponding author:Liu, X.(xiaoluliu9@yahoo.com.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:184-191
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:With the rapid economic and social development in China, rural per capita daily water consumption and sewage emissions have surged, resulting in a large amount of domestic sewage. However, the rural population is a dispersed population, and there are no sewage collection and treatment facilities. Domestic pollution in rural areas is an important factor affecting the water environment, particularly in the water source, and reservoir water quality cannot be ignored. Poor water quality directly harm the health of peasants, and can easily lead to the outbreak and spread of epidemic diseases. Therefore, research and development of both cost savings and operating costs, while maintaining the stability of the phosphorus and nitrogen removal effect of rural domestic sewage treatment process is very necessary. For rural scattered distribution, coupled with a long-standing way of living, habits, and economic status differences, the actual project was the basis to study the establishment of the "rings." The formula (ACGMP, Anaerobic, Constructed wetlands, Genetic engineering of Rice, Microorganism, Pond) was for an eco-efficient rural domestic sewage treatment works system, with the system performing villages sewage treatment for households connected, construction of a sewage anaerobic reactor, constructed wetlands, planting high adsorption pollution factors aquatic plants, efficient investment in the decomposition of sewage dedicated micro-organisms, the use of a natural pond five links, and an entire engineering system power, to achieve complete self-liquidity. The rural domestic sewage treatment works application site is located in the Three Gorges reservoir area in Chunqiu Village, Chongqing. The process design and operating parameters were: a design population of 300, according to the volume of sewage 100 L per person, and sewage treatment capacity of 30-50 m³/d; design flow rate of 30-50 m³/d, design effluent standard GB8987-1996. The process used anaerobic technology and an eco-technology organic combination of artificial substrate and growth of aquatic plants and micro-organisms on which to form a unique soil-plant-microbial ecosystem. Water quality met the national secondary standard of Integrated Wastewater Discharge Standard. Water could be used for the nearby agricultural irrigation, harmless wastewater, recycling and reuse. Through the week, continuous sampling monitoring showed: COD, total phosphorus, SS, ammonia nitrogen decreased slightly lower; TN; hexavalent chromium by adsorption decreased slightly; pH almost not changed, near-neutral; total lead, cadmium total, and mercury was not detected. By monitoring the treated water discharge standards, the impact of the treatment works was obvious. Phosphorus, SS, ammonia decreased slightly lower; TN; hexavalent chromium by adsorption decreased slightly; has not changed, near-neutral pH almost; total lead, cadmium, mercury was not detected by monitoring the treated water discharge standards. Energy required by the system was gravitational energy, solar, bio-energy and other eco-energy, without the need for additional power, so it is energy-saving. Take 50 m³/d scale sewage as example, it only needed 3500 Yuan to invest in dealing with one ton of sewage, with the running costs averaging 0.1 Yuan/t. After being treated by this process, rural sewage basically reached national emission level two standard. This completely changed the village mosquitoes breeding problem, and alleviated obvious odor and other environmental conditions caused by the prior wanton chaotic emission of sewage. It significantly improved the surrounding environment, resulting in praise from the local government and villagers, The rural sewage treatment engineering systems design science, technology integration, process maturity, and obvious characteristics, highlights the advantages of the effect as significant. The process of rural sewage treatment technology quality protection in the Three Gorges reservoir area has opened up a new way to obtain a successful experience. This has an important promotional value and broad application prospects.
Number of references:30
Main heading:Lead removal (water treatment)
Controlled terms:Adsorption - Ammonia - Cadmium - Chromium - Design - Ecology - Effluents - Genetic engineering - Investments - Lakes  - Mercury (metal) - Microorganisms - Phosphorus - Rural areas - Sewage - Sewage treatment - Solar energy - Technology - Wastewater - Wastewater reclamation  - Water conservation - Water pollution - Water quality - Water recycling - Water supply - Water treatment - Wetlands
Uncontrolled terms:Economic and social development - Environmental conditions - five-rings (ACGMP) - National secondary standard - Phosphorus and nitrogen removal - Research and application - Rural domestic sewages - Three gorges reservoir area
Classification code:911.2 Industrial Economics - 461.8.1 Genetic Engineering - 461.9 Biology - 543.1 Chromium and Alloys - 549.3 Nonferrous Metals and Alloys excluding Alkali and Alkaline Earth Metals - 615.2 Solar Power - 802.3 Chemical Operations - 804 Chemical Products Generally - 804.2 Inorganic Compounds - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 901 Engineering Profession - 454.3 Ecology and Ecosystems - 407 Maritime and Port Structures; Rivers and Other Waterways - 408 Structural Design - 442.2 Land Reclamation - 444 Water Resources - 454.2 Environmental Impact and Protection - 445.1 Water Treatment Techniques - 446.1 Water Supply Systems - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 453 Water Pollution - 445.2 Water Analysis
DOI:10.3969/j.issn.1002-6819.2013.09.024
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 8>

Accession number:20132516429362
Title:Mathematical model for N release from polymer-coated controlled-release fertilizers
Authors:Chen, Keke (1); Zhang, Baolin (1)
Author affiliation:(1) College of Chemical Engineering and Energy, Zhengzhou University, Zhengzhou, 450002, China; (2) College of Chemistry and Chemical Engineering, Xinxiang University, Xinxiang, 453002, China
Corresponding author:Zhang, B.(zhangbl@zzu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:123-130
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Controlled release of nutrients from coated fertilizer granules is desired for optimal uptake by plants and crops. We studied the release of amide nitrogen, a non-electrolyte, from a polymer-coated spherical fertilizer granule, having varying influence factors. The release course was divided into three stages: the lag period, the linear stage and the decay stage. An exact mathematical model based on Fick's Second Diffusion Law was developed to predict the release rate of a polymer-coated controlled-release fertilizer using equations of mathematical physics and numerical analysis methods, and Laplace transform and Residue theory were used to solve the equations. From the explicit mathematical model, an approximate solution for the nitrogen release was obtained. The model showed that nitrogen release was mainly controlled by the types of coating materials and their membrane thickness. The models can be used to describe the release rate under different operating conditions. Detailed and approximate solutions were developed and compared with the nutrient release experiments, and different fertilizers were used to verify the approximate release model. Four polymer-coated controlled-release fertilizers, the thermoplastic resin coated fertilizer (1^#, l=0.0586 cm; 3^#, l=0.0065 cm), and alkyd resin coated fertilizer (2^#, l=0.0463 cm; 4^#, l=0.0058 cm), were used in nitrogen release experiments. Release experiments were conducted using the methods of water extraction from GB/T 23348-2009, at 25&deg;C. The effective diffusion coefficient of amide nitrogen was fixed. The experiments showed the nitrogen was mainly released in the linear stage. The release period of alkyd resin coated fertilizers was shorter than the thermoplastic resin coated fertilizers under almost the same membrane thickness. The cumulative percentage of nitrogen release decreased when the membrane thickness increased. The cumulative release profile of nitrogen from the thermoplastic resin coated fertilizer and alkyd resin coated fertilizer into water agreed with the prediction of the model on the whole. The calculated and experimental values of nitrogen release of the thermoplastic resin coated fertilizer in the Lag and Decay stage was better fit than the linear, the relative error range was: 0-37.55%. The best fit between the calculated and experimental values of nitrogen release of the alkyd resin coated fertilizer in the linear stage, the relative error range was: 0-23.06%, and the relative error increased when the release time increased. Understanding these effects quantitatively is very useful in determining the types of coating materials and coating width to use while manufacturing such granules.
Number of references:30
Main heading:Nitrogen fertilizers
Controlled terms:Alkyd resins - Amides - Coatings - Diffusion - Experiments - Extraction - Fertilizers - Granulation - Laplace transforms - Mathematical models  - Nitrogen - Nutrients - Plating - Polymers - Reinforced plastics - Resins
Uncontrolled terms:Approximate solution - Controlled release - Controlled-release fertilizers - Different operating conditions - Effective diffusion coefficients - Experimental values - Mathematical physics - Release experiments
Classification code:931.1 Mechanics - 921.3 Mathematical Transformations - 921 Mathematics - 901.3 Engineering Research - 821.2 Agricultural Chemicals - 817.1 Polymer Products - 815.1.1 Organic Polymers - 815.1 Polymeric Materials - 804.1 Organic Compounds - 804 Chemical Products Generally - 802.3 Chemical Operations - 539.3 Metal Plating - 539 Metals Corrosion and Protection; Metal Plating
DOI:10.3969/j.issn.1002-6819.2013.09.016
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 9>

Accession number:20132516429350
Title:Lightweight design of differential case based on particle swarm optimization algorithm
Authors:Chen, Liqing (1); Zhang, Dong (2); Chen, Wuwei (1); Hu, Fang (1); Huang, Minfeng (3)
Author affiliation:(1) School of Mechanical and Automobile Engineering, Hefei University of Technology, Hefei 230009, China; (2) College of Engineering, Anhui Agricultural University, Hefei 230036, China; (3) Hefei Axle Transmission System and Chassis Automobile Co., Ltd, Hefei 230000, China
Corresponding author:Chen, W.(cww@mail.hf.ah.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:24-31
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The lightweight design for automotive parts and components is a complex, multi-constrained problem concerning system optimization and satisfies various structural performance requirements. Existing studies on the lightweight design for automotive parts and components primarily focus on the automobile body design. Most of them focus on plastic material rather than the castings widely used in automobiles. This paper proposes a lightweight design for the casting of the differential mechanism shell in the assembly of the automotive drive axle. The paper focuses on the shell of the automotive differential mechanism and proposes a design method for optimization based on the combination of Particle swarm optimization algorithm and parameterized model. The main contents include: to first establish a parameterized, three-dimensional model for the differential mechanism shell, calculate the modal numerical values of the first 6 orders of the differential mechanism shell, derive the maximum modal numerical value among the first 6 orders, i.e. 6.22% only through modal test contrast, thus verify the correctness of the model. Second, it establishes three limiting conditions of the differential mechanism, including: the automotive advancing condition during transmission with highest torque of the engine and fist gear of the gear box, and automotive reversing condition and twisting fatigue condition with the highest torque of the engine and reverse gear of the gear box. Based on the PSO algorithm, the paper establishes an optimization design with the goal of minimum mass and maximum root-mean-square value of the safety coefficients and a lightweight design in combination with the parameterized model of the differential mechanism shell. It can be inferred by comparing the relevant performance parameters of the differential mechanism shell before and after the lightweight design that: the maximum stress of optimized model decreases by 12.55% under the advancing condition; the maximum stress of optimized model is 5.74% under the reversing condition; under the condition of torsion fatigue, the minimum safety coefficient has risen to 1.35 from 1.12 after optimization; the shell weight has fallen to 5.67 kg from 6.26 kg after optimization with reduction of 10.4%; and the above analyses demonstrate that the lightweight design is successful. The castings are damaged due largely to fatigue failure and impact failure. We will conduct a further study on the impact failure of castings. The study provides certain references to the design and optimization of the shell of the automotive differential mechanism.
Number of references:30
Main heading:Design
Controlled terms:Algorithms - Automobile engines - Constraint theory - Drive axles - Engines - Finite element method - Gears - Modal analysis - Optimization - Parameterization  - Particle swarm optimization (PSO) - Powertrains - Shells (structures) - Three dimensional
Uncontrolled terms:Design and optimization - Lightweight design - Multi-constrained problems - Particle swarm optimization algorithm - Performance parameters - Root-mean-square values - Structural performance - Three-dimensional model
Classification code:961 Systems Science - 921 Mathematics - 902.1 Engineering Graphics - 663.2 Heavy Duty Motor Vehicle Components - 661.1 Automotive Engines - 612 Engines - 601.2 Machine Components - 408.2 Structural Members and Shapes - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.09.004
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 10>

Accession number:20132516429374
Title:Decision-making reasoning in land-use patch generalization
Authors:Jia, Xiaobin (1); Ai, Tinghua (1)
Author affiliation:(1) School of Resource and Environment Sciences, Wuhan University, Wuhan 430079, China
Corresponding author:Jia, X.(jiaxiaobin_123@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:214-222
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The purpose of this research was to settle the complex issue of handling land use patches in land use data generalization and putting into use the principles and methods of the Agent-based technology through the analysis of the features of the land use patch itself. These patches include the shape, width, size, land use types, and the context of the land use patch which contains the space, semantic neighboring relationship, and the importance in the cartographic region. It also establishes a decision-making mechanism to judge the importance of the land use patch while taking into account a variety of criteria, and considers the geometry and semantic indicators integrated into the reasoning process which can be controlled and operated via an automated procedure from judging the importance of the land use patch to the selection of the scale transformation operators. The researchers conducted an experiment to generalize the land use data of a town from 1:10000 to 1:20000, making use of an agent-based software which was developed for land use data generalization. According to the decision-making mechanism and generalization process mentioned above, the results show that the amount of the land use type and the sum area in the cartographic region remain the same before and after generalization, and the area of the data in which the land use type is road or river is narrow polygon reduced considerably because of the use 'CollapseToLine' operator. Using the 'Eliminate' operator to generalize the data in which the land use type is pits cannot meet the threshold of the minimum area, resulting in loss of the area. In addition to the other area of each land use type data changed a little. The generalized data have no topology errors after using ArcGIS software topology to check, and keep the feature of full coverage with no overlap and no gap, and shortens the time from one week in the past to one day now which used to generalize this data, greatly improving the efficiency of generalization. Because the selection of operators was a computer process based on decision-making reasoning mechanisms, reducing the human participation, the generalization efficiency has been improved for the same data mapping area and equipment and the time was shortened from one week in the past to one day now. The experiments proved that the decision-making reasoning mechanism in land-use patch generalization in this paper is reasonable, and can be applied to actual production data.
Number of references:29
Main heading:Land use
Controlled terms:Automata theory - Database systems - Decision making - Decision theory - Experiments - Mapping - Semantics - Spot welding - Topology
Uncontrolled terms:Agent based technologies - Agent-based softwares - Automated procedures - Decision-making mechanisms - Generalization process - Map generalization - Reasoning mechanism - Scale transformation
Classification code:961 Systems Science - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921 Mathematics - 912.2 Management - 903.2 Information Dissemination - 902.1 Engineering Graphics - 901.3 Engineering Research - 723.3 Database Systems - 723 Computer Software, Data Handling and Applications - 538.2.1 Welding Processes - 403 Urban and Regional Planning and Development
DOI:10.3969/j.issn.1002-6819.2013.09.028
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 11>

Accession number:20132516429364
Title:Study on biomass crust preparation to restore vegetation in drifting sand regions in Minqin
Authors:Wang, Ruijun (1); Chen, Zhenghua (2); Wang, Baitian (1); Wang, Ning (1); He, Jingwei (1)
Author affiliation:(1) College of Soil and Water Conservation, Beijing Forestry University, Beijing 100083, China; (2) Beijing Postdoctoral Workstation of Gansu Yasheng Industrial (Group) Co., Ltd, Beijing 100101, China
Corresponding author:Wang, B.(wbaitian@bjfu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:140-147
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:A new kind of crust preparation, which was composed of biopolymer materials and mineral materials, could promote vegetation recovery of moving dunes in Minqin Country, Gansu Province. Minqin County is surrounded by the Tengger and Badain Jaran desert on the East, West and North sides. The average annual rainfall is 113 mm, while the evaporation is up to 2646 mm, so Minqin Country belongs to the extremely arid continental climate zone. Area of desert and desertification land is up to 1.5&times; 10⁷ hm², which is 94.5% of the Minqin land area. The rest, only 5.5%, is the sole oasis area of Minqin Country. The length of the oasis edge is 408km. Minqin Country is a typical agricultural county in sandy areas. The experiment site was located at the frontier of a moving sand area. Crust preparation and seeds of Artemisia scoparia were used in this experiment. Crust preparation (applying for a patent) contained attapulgite, plaster, cellulose, lignin etc. First, the seeds was sown on the surface of a moving dune with a density of 1000-2000/m². Second, the crust components were mixed with sand (crust preparations: sand (V/V)=3:1), and the mixture sprinkled evenly on the sand surface with a shovel. The thickness of the mixture was about 10 mm. Then water was sprayed onto the sand surface to form a crust. The dosage of water was about 2.5 L/m². Finally, the test area was fenced to prevent access by human and animals. No more manual conservation was implemented later. The thickness of the crust was about 10mm, and its bearing strength was 1-2 kg/cm² (varied according to the thickness of the crust) after two days. Controlled trials were set in the adjacent moving dune. All the materials and operations were the same, but without the crust preparation. The area of the control trials was approximately 2200 m². The project was carried out from August 8-10, 2009. About 10 days after construction, a large number of grass seeds germinated in the crust area, up to 1000 / m². Compared to the control area plant species, the richness and diversity indices were higher in the crust area. Because plants in the crust area germinated earlier in spring and withered later in autumn than in the control area, they had a longer growing season. In the crust area, many plants could grow and survived through the dry season. In September of the following year, the coverage of the dunes' vegetation was up to 38%. These results indicated that this crust preparation method may have potential value in vegetation restoration in the cold and arid regions.
Number of references:30
Main heading:Sand
Controlled terms:Arid regions - Biomolecules - Climatology - Experiments - Minerals - Restoration - Surfaces - Vegetation
Uncontrolled terms:Continental climate - Crust - Minqin - Moving dune - Preparation method - Restoring - Vegetation recovery - Vegetation restoration
Classification code:931 Classical Physics; Quantum Theory; Relativity - 901.3 Engineering Research - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 505 Mines and Mining, Nonmetallic - 951 Materials Science - 482.2 Minerals - 443 Meteorology - 409 Civil Engineering, General - 402 Buildings and Towers - 461.9 Biology
DOI:10.3969/j.issn.1002-6819.2013.09.018
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 12>

Accession number:20132516429380
Title:Optimization on ultrasound-alkali-H<inf>2</inf>O<inf>2</inf> one-bath extraction process of curaua fiber
Authors:Wang, Chunhong (1); Bai, Suyue (1); Ma, Haijun (1); Yue, Xinmin (1); Wu, Meiya (1); Yu, Fei (1)
Author affiliation:(1) School of Textiles, Tianjin Polytechnic University, Tianjin 300387, China
Corresponding author:Wang, C.(cn_wangch@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:267-274
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to prepare a new kind of natural fibers and analysis its properties, the curaua fiber was extracted by the method of ultrasound-alkali-H<inf>2</inf>O<inf>2</inf> one-bath technology. The four parameters of ultrasonic time, alkali treatment time, the concentrations of NaOH and H<inf>2</inf>O<inf>2</inf> were optimized by multiple indicator orthogonal experimental method based on the evaluation factors of fibers diameter, breaking strength and moisture regain. The basic physical properties, adiathermic property together with the antibacterial property of curaua fibers were evaluated. Further more, the mechanism of adiathermic property and the antibacterial composition were explored. The results show that the optimal parameters were ultrasonic time of 70 min, alkali-oxygen one bath time of 100 min, alkali weight concentration of 8 g/L, hydrogen peroxide weight concentration of 12 g/L in the solution of 0.75 L. The extracted curaua fibers are 47.19 &mu;m in diameter, 152.59 mm in length, 2.03 &times; 10^-4 MPa in tensile strength and 15.33% in moisture regain, which are comparable with ramie fibers. The curaua/cotton(70/30) net with the CLO value of 1.316 and the thermal resistance of 0.204 m² &middot K/W, has certain warmth retention property, which is slightly lower than wool fibers net. In vitro antibacterial test, we found that curaua fiber has excellent antibacterial effect to colibacillus and staphylocccus aureus. In addition, the SEM pictures show that there are lumens in the cross section of the fibers. The filter liquor of curaua fiber has flavonoids of antimicrobial substances, which was tested by the ultraviolet spectroscopy.
Number of references:31
Main heading:Fibers
Controlled terms:Extraction - Optimization - Tensile strength - Ultrasonics - Ultraviolet spectroscopy - Wool fibers
Uncontrolled terms:Adiathermic - Antibacterial - Antibacterial effects - Antibacterial properties - Antimicrobial substance - Curaua fibers - Experimental methods - Orthogonal analysis
Classification code:921.5 Optimization Techniques - 819.1 Natural Fibers - 817 Plastics and Other Polymers: Products and Applications - 812 Ceramics, Refractories and Glass - 802.3 Chemical Operations - 801 Chemistry - 753.1 Ultrasonic Waves - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties
DOI:10.3969/j.issn.1002-6819.2013.09.034
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 13>

Accession number:20132516429359
Title:Characteristics of spatial distribution of soil water-air-heat parameters in typical oasis croplands at middle reaches of Heihe River
Authors:Wang, Weihua (1); Wang, Quanjiu (1); Wu, Xiangbo (1); Wang, Shuo (1)
Author affiliation:(1) Institute of Water Resources and Hydro-electric Engineering, Xi'an University of Technology, Xi'an 710048, China; (2) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, The Chinese Academy of Sciences, Yangling 712100, China
Corresponding author:Wang, Q.(wquanjiu@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:94-102
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Using statistical methods for a study on the spatial variations of soil properties has become one of hot topics in the study of soil science. Due to the deep research on the spatial variation of soil hydraulic parameters, and the lack of research on the dynamic characteristics of soil air and heat transfer, we cannot compare the spatial variation characteristics of soil, water, air, and heat transfer kinetic parameters. As the interaction between the soil and the environment as well as the precise regulation of farmland soil moisture, air and heat condition problem is receiving more and more attention, the numerical model used to study the soil moisture, air and heat transport process, effectiveness and its impact on crop growth and ecological environment has gradually become a reality. But model accuracy depends largely on the accuracy of soil, water, air, and heat transfer kinetic parameters. Thus, seeking a simple and feasible method of determining the thermal dynamic parameters of soil moisture is the focus of research around the world. In order to define the dynamiccharacteristics of water conductivity, air permeability and heat conductivity's spatial variability, this paper examines the spatial variation of the above parameters in Linze County, an agricultural area in the middle reaches of the Heihe River Basin. PL-300 soil air permeability measurement and soil heat pulse meter were applied to measured soil air permeability and thermal conductivity. In this paper, we designed an experiment of four levels of moisture content and took the average of three replications. Hydraulic conductivity is measured by qdisc infiltration instrument, each measuring point design four suction head, based on a spatial analysis function of GIS, The results showed as follows: 1) simulate the spatial structure and variability of the water, air, and heat parameters using land statistics of a wheat field. The optimal fitting model for saturated hydraulic conductivity, air permeability, thermal conductivity are an exponential model, the sum of squared residuals are small, nearly zero, and the determination coefficient R² reached more than 80%. The results show that the statistical method can better simulate the spatial structure and variation characteristics of soil moisture air and thermal parameters. Fractal dimension (D) was close to 2, illustrating that soil water conductivity, air permeability and heat conductivity have strong spatial variation characteristics in this region. 2) Saturated hydraulic conductivity, air permeability and heat conductivity's C / (C C<inf>0</inf>)&gt;75%, had a strong degree of spatial autocorrelation in the study scale. Recommend sampling distances of hydraulic conductivity, air permeability and heat conductivity both are 10m. And sampling distances of the other soil physical parameters are recommend to be 4m. 3) Kringing interpolation results show that soil water and gas parameters change was having a certain degree of consistency, Thermal conductivity has certain regional characteristics in the study area. The higher the moisture content, bulk density and the greater the sand content are, the greater the thermal conductivity is, and the thermal conductivity has certain regional characteristics. Among the soil, thermal conductivity is high, the north and south were on both sides of the lower tendency in the saddle. The research will be for the local soil moisture, air and thermal parameters field scale space mutation research to provide a certain reference basis.
Number of references:31
Main heading:Geologic models
Controlled terms:Agriculture - Air permeability - Fractal dimension - Heat transfer - Hydraulic conductivity - Kinetic parameters - Moisture - Moisture determination - Research - Soil moisture  - Soils - Space applications - Spatial variables measurement - Statistical methods - Thermal conductivity - Thermal conductivity of gases
Uncontrolled terms:Determination coefficients - Geo-statistics - Saturated hydraulic conductivity - Soil hydraulic parameters - Soil water conductivities - Spatial autocorrelations - Spatial variability - Variation characteristics
Classification code:944.2 Moisture Measurements - 901.3 Engineering Research - 921 Mathematics - 922.2 Mathematical Statistics - 931 Classical Physics; Quantum Theory; Relativity - 931.2 Physical Properties of Gases, Liquids and Solids - 943.2 Mechanical Variables Measurements - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 656 Space Flight - 641.2 Heat Transfer - 632.1 Hydraulics - 483.1 Soils and Soil Mechanics - 481.1 Geology - 801.4 Physical Chemistry
DOI:10.3969/j.issn.1002-6819.2013.09.013
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 14>

Accession number:20132516429355
Title:Nano-fuel additive CeO<inf>2</inf> on promoting efficient combustion and reducing emissions of diesel engine
Authors:Wu, Qimin (1); Sun, Ping (1); Mei, Deqing (1); Sun, Zhu (1); Ji, Yanping (1)
Author affiliation:(1) Vehicle and Engine Emission Research Institute, Jiangsu University, Zhenjiang 212013, China
Corresponding author:Wu, Q.(wuqiminwuqimin@126.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:64-69
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Developing new and highly efficient fuel additives have become an important topic of controlling engine combustion and emissions. For its unique physiochemical properties, nano-particles CeO<inf>2</inf> makes it own a unique role in the field of catalytic combustion and exhaust gas purification. Through adding a trace amount of nano-particles CeO<inf>2</inf> to diesel oil, two CeO<inf>2</inf>-diesel blends with the masse fraction of 50 and 100 mg/L of nano-particles CeO<inf>2</inf> have been prepared, which makes D50C, D100C and Diesel these three test fuels, together with pure diesel as a reference. And the influences of these three test fuels on 186FA diesel engine combustion and emission have been investigated. The results show that: By using physical and chemical methods such as adding surfactant and ultrasonic processing, nano-particles CeO<inf>2</inf> can be suspended stably in diesel. At full load at rated speed, the in-cylinder pressure peak, pressure rise rate peak and heat release rate peak have increased slightly when engine fuelled with D50C and D100C, while the corresponding crank angles are in advance accordingly, their ignition delay periods are also shorten by 1&deg; or 2&deg; crank angle accordingly. The engine's brake specific fuel consumption has reduced slightly with the effective thermal efficiency slightly increased when fuelled with D50C and D100C. Four conventional pollutants have reduced with different degrees with the addition of nano-particles CeO<inf>2</inf> into diesel, and their reduction margins are more evident with the increase of the amount of nano-particles CeO<inf>2</inf> in diesel. As compared to diesel, at full load at rated speed, the brake specific fuel consumption of D50C and D100C have droped 1.6% and 2.3% with a increase of 1.7% and 2.3% in corresponding effective thermal efficiency. The CO, HC, NOx and smoke emissions of D50C and D100C have decreased in average by 3.4% and 6.5%, 15.1% and 18.4%, 2.4% and 5.4%, 4.0% and 7.8%, respectively. The costs of D50C and D100C blends are 0.8% and 1.6% higher than that of diesel. On the whole, with a slight increase in fuel price through the trace addition, nano-particles CeO<inf>2</inf> is a kind of fuel additives with excellent performance, which can achieve highly combustion, energy conservation and emission reduction of engine.
Number of references:27
Main heading:Diesel engines
Controlled terms:Catalysis - Combustion - Diesel fuels - Emission control - Engines - Fuel additives - Nanoparticles - Particulate emissions
Uncontrolled terms:Brake specific fuel consumption - CeO<inf>2</inf> - Diesel engine combustions - Efficient combustions - Heat Release Rate (HRR) - In-cylinder pressures - Physio-chemical properties - Ultrasonic processing
Classification code:933 Solid State Physics - 803 Chemical Agents and Basic Industrial Chemicals - 802.2 Chemical Reactions - 761 Nanotechnology - 708 Electric and Magnetic Materials - 612.2 Diesel Engines - 612 Engines - 524 Solid Fuels - 523 Liquid Fuels - 522 Gas Fuels - 521.1 Fuel Combustion - 451.2 Air Pollution Control - 451.1 Air Pollution Sources
DOI:10.3969/j.issn.1002-6819.2013.09.009
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 15>

Accession number:20132516429349
Title:Research of materials motion law in separation flow of new type hammer feed grinder
Authors:Wang, Jianxin (1); Zhang, Guangyi (1); Cao, Liying (1)
Author affiliation:(1) Department of Mechanical Engineering, Inner Mongolia University of Science and Technology, Baotou 014010, China
Corresponding author:Cao, L.(kdcly@imust.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:18-23
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to fundamentally solve the existing problem of high temperatures of material, excessive crushing, and low separation efficiency in traditional pulverizers, a new type of hammer crusher to be used for conventional crushing, separation mode, and annular tooth plate were installed in the grinding chamber, while the sieve was not installed. Its' ability to crush materials rely's on striking and friction, and used the separation means to separate the materials. The materials that met the size requirements were immediately pushed through a sieve, and particle materials which failed to meet the size requirements went back to the crushing chamber for circulation crushing under the double action of the crushing chambers central negative pressure and high material weight. Basing on the working condition of the feed hammer crusher, we studied the mathematical mode of material particles in gas-solid, two-phase flow trajectory, and determined the material motion differential equation and displacement equation of x axis and y axis direction. According to the actual prototype separation flow parameters, we used MATLAB to analyze the numerical simulation. We set the material grain equivalent diameter to 2 mm, where the collision between material and the channel wall is a perfectly elastic collision. We also used the intersection between separation channel entrance and wall surface on the outer as the X axis / Y axis coordinate plane (0, 0) point position, where the granular material entrance initial position are respectively (0, 25 mm), (0, 50 mm), (0, 100 mm), and (0, 150 mm). We determined the material motion track by utilizing different angles, initial velocity, and inlet position in the runner trajectory. The results show that entrance velocity at the angle of 45&deg; is very proper, without collisions between particles and the separation channel, while at the same time it can easily reach the screen surface through the screen. Due to the separation channel being relatively short and the high velocity of the materials, the particle trajectory is minimally affected by gas phase and gravity. Through tracking the shooting of the particles with a high speed camera in the separation channel, we verified the rationality of the mathematical model. We also made comparisons of material simulation positions and real positions. The studies show that: the movement track of theorized material particles and practice material particles is basically the same, the target particle error is 0-3.5 mm; and the intact granules error is 0-3.3 mm. From the plan, it also can be seen that wind effects are larger for the 2 mm target particles and the actual trajectory is located above the trajectory of theoretical model; however, the energy change of 8mm intact grains is greater because of gravity, and particle collisions, and other factors, while the actual motion trajectories float in the vicinity of theoretical trajectories. The main reasons for this difference occurring: (1) The theoretical mathematical model did not consider the material motion effects between the material interaction; (2) Particle size influences the selection of particle motion parameters, particularly the effect of particle velocity in separation flow. We hope that the study of hammer fodder grinder movement law in separation flow can provide a reference for further study of macro material movement, particle size distribution, and structure of the separating device.
Number of references:26
Main heading:Materials
Controlled terms:Computer simulation - Crushers - Crushing - Differential equations - Grinding mills - Hammers - High speed photography - Mathematical models - MATLAB - Models  - Particle size analysis - Particles (particulate matter) - Separation - Sieves - Trajectories - Wind effects
Uncontrolled terms:Displacement equation - Equivalent diameter - Material interactions - Motion differential equation - Motion trajectories - Particle trajectories - Separation efficiency - Theoretical trajectory
Classification code:921.2 Calculus - 921 Mathematics - 902.1 Engineering Graphics - 802.3 Chemical Operations - 802.1 Chemical Plants and Equipment - 951 Materials Science - 742.1 Photography - 605.2 Small Tools, Unpowered - 605 Small Tools and Hardware - 443.1 Atmospheric Properties - 404.1 Military Engineering - 723.5 Computer Applications
DOI:10.3969/j.issn.1002-6819.2013.09.003
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 16>

Accession number:20132516429375
Title:Sampling method for monitoring classification of cultivated land in county area based on Kriging estimation error
Authors:Yang, Jianyu (1); Tang, Sai (1); Yun, Wenju (2); Zhang, Chao (1); Zhu, Dehai (1); Chen, Yanqing (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China; (2) Land Consolidation and Rehabilitation Center, Ministry of Land and Resources, Beijing 100035, China; (3) Key Lab for Agricultural Land Quality, Monitoring and Control of the Ministry of Land and Resources, Beijing 100035, China
Corresponding author:Yang, J.(ycjyyang@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:223-230
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:China, an agricultural country, has a large population but not enough cultivated land. Until 2011, the cultivated land per capita was 1.38 mu (0.09 ha), only 40% of the world average, and it is getting worse with industrialization and urbanization. The next task for the Ministry of Land and Resources: Dynamic monitoring of cultivated land classification in which a number of counties will be sampled; in each county, a sample-based monitoring network would be established that reflects the distribution and its tendency of cultivated land classification in county area and estimates of non-sampled locations. Due to the correlation among samples, traditional methods such as simple random sampling, stratified sampling, and systematic sampling are insufficient to achieve the goal. Therefore, in this paper we introduced a spatial sampling method based on the Kriging estimation error. For our case, natural classifications of cultivated land identified from the last Land Resource Survey and Cultivated Land Evaluation are regarded as the true value and classifications of non-sampled cultivated lands would be predicted by interpolating the sample data. Finally, RMSE (root-mean-square error) of Kriging interpolation is redefined to measure the performance of the network. To be specific, five steps are needed for the monitoring network. First, the optimal sample size is determined by analyzing the variation trend between the number and the accuracy of samples. Then, set up the basic monitoring network using square grids. The suitable grid size can be chosen by comparing the grid sizes and the corresponding RMSEs from the Kriging interpolation of the samples data. Because some centers of grids do not overlap the area of cultivated land, the third step is to add some points near the centers of grids to create the global monitoring network. These points are selected from centroids of cultivated land spots which are closest to the centers and inside the searching circles around the centers by a loop algorithm. The fourth step is a procedure of densification, which is needed to build Thiessen polygons through global sampling points. Then, add the point of maximum Kriging estimation error inside polygons whose RMSEs are relatively high to the network only if it makes the global RMSE smaller. This procedure stops when the count of sampling points reaches the optimal sample size. The final step is to replace several monitoring points by standard plots to reduce the sampling cost. Finally, estimate the population mean of cultivated land classification through Kriging interpolation. Experiments in Beijing Daxing district that compared this method to traditional sampling methods in cost (count of sampling points), estimation accuracy (measured by RMSE), and prediction accuracy of the population mean illustrate that the estimation accuracy of this method is higher than simple random sampling, stratified sampling, or traditional grids when the number of sampling points is 48. Besides, the prediction accuracy of population mean stays in an accurate level with the relative error of 0.07%. Therefore, this method can meet the needs of monitoring the classification of cultivated land in county area.
Number of references:28
Main heading:Land use
Controlled terms:Estimation - Grading - Interpolation - Monitoring
Uncontrolled terms:Cultivated lands - Kriging - Kriging interpolation - Root-mean square errors - Simple random sampling - Spatial sampling - Stratified sampling - Thiessen polygon
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 921.6 Numerical Methods - 913.3 Quality Assurance and Control - 403 Urban and Regional Planning and Development - 921 Mathematics
DOI:10.3969/j.issn.1002-6819.2013.09.029
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 17>

Accession number:20132516429378
Title:Modified Burger's model for describing creep behavior of tomato fruits
Authors:Liu, Jizhan (1); Bai, Xinxin (1); Li, Pingping (2)
Author affiliation:(1) Key Laboratory of Modern Agricultural Equipment and Technology, Ministry of Education, Jiangsu University, Zhenjiang, 212013, China; (2) College of Forest Resources and Environment, Nanjing Forestry University, Nanjing 210037, China
Corresponding author:Liu, J.(liujizhan@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:249-255
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In this paper, creep deformation and recovery tests were processed for tomato fruits first with a TA-XT2i texture analyzer by randomly selecting every ten tomato fruits for a different ripening period. It was found the classical Burger's model failed to express the strain saturation at the later creep objectively due to the constant Newtonian viscosity of the free dashpot, but the existing modified exponential and power-law models have also have the major defect that the viscosity of free dashpot at the later creep and initial deformation rate tend to infinity, respectively. So a new model that consisted of four elements with six parameters modified was proposed, by changing the constant Newtonian viscosity of a free dashpot to a power-law variable with a constant term in the viscous deformation term of the creep equation of Burger's model. And then the curve fitting and prediction results of the new model were compared with those of Burger's model and the existing modified exponential and power-law models. The average determination coefficient and the sum of squares due to the regression error of different ripening periods with the new model were 0.9975-0.9994 and 0.04047-0.07633, respectively, which are more ideal, obviously. The average relative errors of the rate of creep deformation, and the rate of elasticity with the new model were only 2.54%-3.04% and 2.89%-7.12%, respectively. The average relative error of the creep deformation prediction with the new model were 0.29%-0.46%, which are several times less than not only the Burger's model but also the existing modified exponential and power-law models. Finally, the initial creep deformation rate of the new model was also closer to the real rate than any other models. To conclude, this study used a good 4-element with 6-parameter modified model to express and predict the creep behavior more accurately, which gives a better model option to bruise reducing in fruit harvesting, transporting or sorting.
Number of references:23
Main heading:Creep
Controlled terms:Curve fitting - Elasticity - Forecasting - Fruits - Models - Vaporization - Viscoelasticity - Viscosity
Uncontrolled terms:Average relative error - Creep deformations - Determination coefficients - Modify - Newtonian viscosity - Strain saturation - Tomato - Viscous deformation
Classification code:921 Mathematics - 902.1 Engineering Graphics - 821.4 Agricultural Products - 951 Materials Science - 802.3 Chemical Operations - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties - 631.1 Fluid Flow, General
DOI:10.3969/j.issn.1002-6819.2013.09.032
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 18>

Accession number:20132516429347
Title:Risk assessment for regional food security based on models of food supply-demand gap
Authors:Qi, Xiaoxing (1); Liu, Liming (1); Liu, Yabin (1)
Author affiliation:(1) College of Resources and Environment, China Agricultural University, Beijing 100193, China
Corresponding author:Liu, L.(liulm@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:1-8
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Food security never fails to attract high attention of researchers and policy makers, especially in China, which has more than one fifth of the world's population, but where the total cultivated area accounts for only about seven percent of the world's total cultivated area. However, thus far, relevant studies were normally conducted at the national level, which generally considered China's food security as a whole or used a single set of index system for analysis. Therefore, study on food security from a regional scale will be of great value for policy makers. This paper mainly focuses on the risk sources which can cause food insecurity in China. We proposed a series of supply-demand estimation models to evaluate the gap between supply and demand of food in different areas (food output areas, food import areas and food supply-demand balance areas). Based on different demand-supply gap ratios, the food security risks are categorized into four grades: negligible risk, low risk, medium risk, and high risk. After that, a case study was conducted in the Dongting Lake area. We analyzed the impact of natural disasters under different scenarios (general scenario, pessimistic scenario and optimistic scenario), use Cobb-Douglas stochastic frontier model to predict resources constraint and inputs constraint on food supply, and evaluate the future food security risk under different scenarios. The results show that if annual grain shortfalls caused by natural disasters at the historical average level, there will be 2, 2 and 4 counties/cities at the low-risk range, medium-risk range and high-risk range in 2015, respectively; and the number of counties/cities at the medium-risk range will increase to 3 by 2020. If annual grain shortfalls caused by natural disasters at the historical worst level, there will be 2, 5 and 7 counties/cities at the low-risk range, medium-risk range and high-risk range in 2015, respectively; and the number of counties/cities at the high-risk range will increase to 9 by 2020. If annual grain shortfalls caused by natural disasters at the historical lowest level, there will be no significant changes in the risk range of all counties/cities. Overall, natural disaster is a main source of food supply risk and population growth is the most common risk factor that could cause food insecurity in the Dongting Lake area; Resources and input elements will have a positive impact for future food supplies in most counties and cities. However, there will be no gap between supply and demand of food if we are considering Dongting Lake area as a whole.
Number of references:33
Main heading:Food supply
Controlled terms:Decision making - Disasters - Economics - Lakes - Models - Population statistics - Risk assessment - Stochastic models
Uncontrolled terms:Dongting Lake area - Estimation models - Food security - Population growth - Stochastic frontier models - Supply and demand - Supply-demand - Supply-demand balances
Classification code:922.2 Mathematical Statistics - 922.1 Probability Theory - 912.2 Management - 971 Social Sciences - 902.1 Engineering Graphics - 407 Maritime and Port Structures; Rivers and Other Waterways - 404.2 Civil Defense - 484 Seismology
DOI:10.3969/j.issn.1002-6819.2013.09.001
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 19>

Accession number:20132516429352
Title:Ride comfort evaluation of vibratory roller under different soil ground
Authors:Le Van Quynh (1); Zhang, Jianrun (1); Liu, Xiaobo (3); Wang, Yuan (1); Thoan, P.V. (4)
Author affiliation:(1) School of Mechanical Engineering, Southeast University, Nanjing 211189, China; (2) Faculty of Mechanical Engineering, Thai Nguyen University of Technology, Thai Nguyen, 23000, Viet Nam; (3) CSR Zhuzhou Electric Locomotive Co., Ltd., Zhuzhou, 412001, China; (4) State Key Laboratory of Advanced Design and Manufacturing for Vehicle Body, Changsha 410082, China
Corresponding author:Zhang, J.(zhangjr@seu.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:39-47
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In realistic working conditions, a vibratory roller operates and moves on various kinds of soil ground and when it does vibration excitation sources, such as soil ground, drum and engine are transmitted to the driver through the isolation systems of the cab and seat, which has direct influence on the driver's health and their working efficiency. Thus, in order to evaluate the riding comfort of a vibratory roller under the different soil grounds, a nonlinear dynamics model of a single drum vibratory roller was established in this paper, based on the analysis of the contact physics of the wheel with different soil grounds. In order to describe the vertical excitation force acting on the front frame generated by a vibratory drum with elastic-plastic soil, a 3-DOF vibration model which describes vibratory drum operating is developed in this study, based on Adam D. and Kopf F's elastic-plastic soil model. Using Bekker's hypothesis of the soft soil ground, the tire- deformation soil surface contact model was established to analyze the vertical excitation force acting on the rear frame. Matlab/Simulink software was used to simulate the nonlinear dynamic models and calculate the values of the vertical weighted r.m.s acceleration responses of driver's seat and cab. The nonlinear dynamics model of the whole vehicle was analyzed according to the ISO 2631:1997 (E) standard, the influence of noise and vibration to human health which evaluates the influence of the different road conditions, operating conditions, and vehicle speeds on the driver's ride comfort. The results showed that the rigid road surface roughness level has a greater influence on vibratory roller ride comfort that a driver subjectively feels is very uncomfortable when the vehicle moves on a poor road surface roughness. The deformation of the road surfaces dominate cab sloshing when a vehicle moves on relatively soft soil road surface. And in a low frequency region, vehicle ride comfort becomes worse when there are vibratory compacts and moves on elastic-plastic soil. The study can provide a reference for vibration roller ride comfort design.
Number of references:29
Main heading:Geologic models
Controlled terms:Computer simulation - Deformation - Dynamic models - Elastoplasticity - Riding qualities - Roads and streets - Rollers (machine components) - Soils - Vibrations (mechanical)
Uncontrolled terms:Elastic-plastic soils - Evaluation - Low frequency regions - Matlab/Simulink software - Non-linear dynamics model - Road surface roughness - Vibration excitation sources - Vibratory rollers
Classification code:921 Mathematics - 723.5 Computer Applications - 682.1.1 Railroad Cars - 601.2 Machine Components - 931.1 Mechanics - 483.1 Soils and Soil Mechanics - 422 Strength of Building Materials; Test Equipment and Methods - 421 Strength of Building Materials; Mechanical Properties - 406.2 Roads and Streets - 481.1 Geology
DOI:10.3969/j.issn.1002-6819.2013.09.006
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 20>

Accession number:20132516429356
Title:Increase insulation effect of polyurethane board pasting on closed aqueduct surface in cold regions
Authors:Liu, Deren (1); Zhang, Dong (3); Zhang, Shimin (2)
Author affiliation:(1) School of Civil Engineering, Lanzhou Jiaotong University, Lanzhou 730070, China; (2) State Key Laboratory of Frozen Soil Engineering, Cold and Arid Regions Environmental and Engineering Research Institute, Chinese Academy of Sciences, Lanzhou 730000, China; (3) Gansu Water Conservancy and Hydroelectric Survey Design Institute for Research, Lanzhou 730070, China
Corresponding author:Liu, D.(liuderen@mail.lzjtu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:70-75
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Areas of northern China are mainly in the temperate monsoon climate zone and temperate continental climate zone, it is cold in winter, and the air temperature is low, which has a big influence on water diversion facilities, especially aqueduct. As for closed aqueduct water diversion projects which need to be operated in winter with non-pressure water delivery in cold regions of northern China, it is of great significance to study and research the safe operation under low temperature environment in winter. With the rapid development of the construction of water diversion projects, the original research results about aqueducts mainly lie in the structural stress of the aqueduct, then the effects of fluid-solid coupling, earthquake, wind and temperature stress, and other factors are gradually considered, seismic and reliability theory is also introduced into the design of diversion facilities. For water diversion projects in northern China, the problem of the safety of water diversion under low temperature environments in winter should also be considered. The present study in freezing disease of water diversion project and safety operation in winter is relatively less, which are mainly in the fields of monitoring analysis and numerical calculation analysis. In this paper, according to an aqueduct engineering practice with non-pressure water delivery in cold region of northern China, a scale model test of an aqueduct is undertaken in an indoor environment cabinet to study the anti-freezing and insulation effects of pasting polyurethane insulation board on the surface of the aqueduct under low temperature environment in winter. In order to study the insulation effects of polyurethane insulation board on aqueduct, the tests are mainly divided into two cases: pasting and without pasting polyurethane insulation board on the surface of the aqueduct model. By the tests, the influence of the external environment temperature and rate of flow on water flow temperature during the process of water delivery of the aqueduct in winter were studied. It is concluded from the test that pasting polyurethane insulation board on aqueduct surface has obvious effects on preventing the water temperature in the aqueduct from decreasing, reducing about 45% of the water temperature reduction. In order to ensure the insulation effects of polyurethane insulation board, polyurethane insulation board should be pasted on the surface of aqueducts closely to prevent phenomena of bulging and shedding. The aqueduct is exposed to the atmosphere and is seriously affected by the temperature, so when setting aqueduct in actual water diversion project, it should not be set too long to ensure the safe operation of these projects. Test results in the paper can provide design basis and reference for the same closed aqueduct water diversion project in cold regions of northern China.
Number of references:26
Main heading:Insulation
Controlled terms:Atmospheric temperature - Earthquakes - Experiments - Flood control - Freezing - Models - Polyurethanes - Reliability theory - Safety engineering - Seismic design  - Temperature - Water supply
Uncontrolled terms:Aqueduct - Cold regions - Engineering practices - External environments - Low temperature environment - Numerical calculation - Polyurethane insulation - Water diversion project
Classification code:922.2 Mathematical Statistics - 914.1 Accidents and Accident Prevention - 914 Safety Engineering - 902.1 Engineering Graphics - 901.3 Engineering Research - 822.2 Food Processing Operations - 815.1.1 Organic Polymers - 641.1 Thermodynamics - 484 Seismology - 446.1 Water Supply Systems - 443.1 Atmospheric Properties - 413 Insulating Materials - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.09.010
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 21>

Accession number:20132516429348
Title:Design and experiment on double cam-link of continuously variable transmission for seeding and fertilizing
Authors:Zhang, Dongyuan (1); He, Jin (1); Li, Hongwen (1); Wang, Qingjie (1); Zhang, Xiangcai (1); Zheng, Zhiqi (1); Lu, Zhanyuan (2); Wang, Song (3)
Author affiliation:(1) Beijing Key Laboratory of Optimized Design for Modern Agricultural Equipment, College of Engineering, China Agricultural University, Beijing 100083, China; (2) Inner Mongolia Academy of Agricultural and Animal Husbandry Sciences, Hohhot 010031, China; (3) China Agricultural Machinery Testing Center, Ministry of Agriculture, Beijing 100122, China
Corresponding author:He, J.(hejin@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:9-17
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In China, there are relatively few types of mechanical, continuously variable transmissions for variable rate seeding and fertilizing, while the electronic hydraulic application has the disadvantages of high cost, limited adjustable range, and poor accuracy and uniformity of distribution. To address these problems, and according to the analysis of the desired variable application rate of adjusting seed and fertilizer, the factors of the manufacturing costs, and the reliability of the structure for medium and small scale size farming operation, this paper put forward a method to achieve the variable speed of a transmission system based on a cam mechanism and connecting lever mechanism, designed the relevant parameters through the above principle mechanism, and developed the double cam link of continuously variable transmissions. The transmission achieved the variable rate of seeding and fertilizing through the simultaneous combined action of the output mechanism, transmission mechanism, and adjusting mechanism. In addition, in order to shorten the development processing cycle, reduce manufacturing cost, and increase the application efficiency, the three-dimensional modeling, simulation analysis, and optimization design were done based on Pro/E platform before the experiment prototype was put into manufacturing. The final analyzed kinematics simulation showed that the mechanisms of a continuously variable application rate transmission were reasonable, the quality of the cam contour curve was high, and the design scheme was feasible. Furthermore, for the purpose of testing the performance of the prototype which was manufactured accurately, a suit testing system that can simulate the actual operating environment of planter in the field was developed to calibrate the variable transmission's working accuracy and the uniformity of stability. Particularly, the system can perform satisfactorily with the double cam link of a continuously variable desired transmission both qualitatively and quantitatively. After multiple sets of performance calibrations of this experiment and data were analyzed, the results indicated that as transmission ratio changed, the relative error of measured output speed ranged from 0 to 10%, and the fluctuation range near the theoretical value of measured duty cycle was less than 10%, which met the requirement of transmission accuracy and stability. This study can provide some references for the development and design of continuously variable rate applications into small and medium scale agricultural farming machinery based on the above design and tests parameters, and at the same time, it can help to promote the development of exact seed and fertilizer use efficiency in agricultural mechanization operation, especially in China.
Number of references:25
Main heading:Seed
Controlled terms:Agricultural machinery - Agriculture - Cams - Computer simulation - Cost benefit analysis - Experiments - Fertilizers - Hydraulic machinery - Industrial applications - Machine design  - Manufacture - Reliability analysis - Three dimensional - Three dimensional computer graphics
Uncontrolled terms:Agricultural mechanization - Continuously variable transmission - Performance calibrations - Planter - Three-dimensional modeling - Transmission mechanisms - Variable rate application - Variable transmission
Classification code:913 Production Planning and Control; Manufacturing - 911 Cost and Value Engineering; Industrial Economics - 901.3 Engineering Research - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 913.4 Manufacturing - 804 Chemical Products Generally - 632.2 Hydraulic Equipment and Machinery - 601.3 Mechanisms - 601 Mechanical Design - 723.5 Computer Applications
DOI:10.3969/j.issn.1002-6819.2013.09.002
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 22>

Accession number:20132516429371
Title:Odor pollutants analyzing during municipal solid waste (MSW) composting
Authors:Zhang, Hongyu (1); Li, Guoxue (2); Yang, Qingyuan (2)
Author affiliation:(1) Beijing Building Materials Academy of Science Research, State Key Laboratory of Solid Waste Reuse for Building Materials, Beijing 100041, China; (2) College of Resource and Environment Science, China Agricultural University, Beijing 100193, China
Corresponding author:Li, G.(ligx@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:192-199
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Odor pollution caused by municipal solid waste (MSW) treatment plants has become a growing public concern. The 15-80 mm MSW fraction used in this study was collected from the Xiaowuji MSW pre-sorting station of Beijing. The 15-80 mm MSW consisted of 67% kitchen waste, 18% paper, 6% plastic, and 9% other wastes. The treatments were analyzed using a 60 L heat insulated composting vessel with forced aeration systems. The vessel was loaded with about 29 kg of 15-80 mm MSW, and controlled by the C-LGX program, which enables aeration to be controlled automatically by time or inside temperature. Aeration consisted of pumping ambient air into the reactor continuously at a rate of 0.2 L/kg.min dry matter. Odors were analyzed using a Model 5975N Gas Chromatography-Mass Selective Detector (Agilent Technologies, USA) coupled with an Entech 7890 Preconcentrator (Entech Instruments Inc., CA, USA). An SOC-01 sampling device (Tianjin Dylan Auto Environmental Protection Sci-tech Company, Ltd. China) was used to collect the gas sample. Three-stage cryo-trapping was used to concentrate VCS's in air samples before GC-MSD analysis. In the first stage, 50 mL air samples were drawn through a liquid nitrogen trap with glass beads at -150&deg;C at a flow rate of 100 mL/min. After this, the first-stage trap was heated to 10&deg;C and the trapped gases were transferred by 40 mL helium at a flow of 1.5 mL/min to a second-stage trap at -40&deg;C. The second stage trap was then heated to 180&deg;C, after which the thermally desorbed gases were transferred to a third-stage cryo-focusing capillary trap at -170&deg;C by 30 mL helium at a rate of 1.5 mL/min. The cryo-focusing trap was then rapidly heated to 100&deg;C and the VSC's were finally transferred to the GC-MSD system for determination. For analysis, an HP-1 capillary column (60 m&times;0.32 mm&times;1.0 mm, Agilent Technologies, USA) was used with helium as the carrier gas. The GC oven temperature was initially set at -50&deg;C, where it was held for 3 min, after which it was increased to 35&deg;C at 15&deg;C/min, then to 150&deg;C at 5&deg;C/min, and then to 220&deg;C at 15&deg;C/min, where it was held for 7 min. The oxygen and H<inf>2</inf>S content was analyzed daily using a portable biogas analyzer. Composting gas samples were extracted using a suction pump (built-in biogas analyzer, gas flow: 550 mL/min) and then transferred to the inlet port of the biogas analyzer via a Teflon hose that contained a filter element (2.0 &mu;m PTFE) installed in the middle of the pipe. Measurements were taken for about 90 seconds, and measured values of O<inf>2</inf> and H<inf>2</inf>S were read directly from the screen. The results from this study indicate that there are 50 kinds of volatile organic compounds (VOC's) with particle size of 15-80 mm during MSW composting, including 5 kinds of sulfur odor compounds, 25 kinds of hydrocarbon compounds, 14 kinds of aromatic compounds and 6 kinds of other odor compounds. The correlation analysis show that the odor concentration is significantly correlated with the emissions of sulfurated hydrogen, dimethyl sulfide, carbon disulfide, methyl disulfide, 1, 3-dimethyl and o-xylene (p&lt;0.01). Considering of the detection olfactory threshold of all odor compounds, priority control sequence of the odors were sulfureted hydrogen&gt;dimethyl sulfide&gt;methyl disulfide&gt;carbon disulfide&gt;1, 3-dimethyl&gt; o-xylene. With the low olfactory threshold of methanthio, even if the emission concentration was very low, it would produce serious odor pollution. Furthermore, NH<inf>3</inf> contribution to odor concentration was relatively small, but its emissions were relatively high. It should also focuse on monitoring and control of the methanthio and NH<inf>3</inf> during the particle size of 15-80 mm MSW composting. This study can provide a reference for monitoring of odor substances and making control strategy.
Number of references:30
Main heading:Municipal solid waste
Controlled terms:Air quality - Biogas - C (programming language) - Carbon disulfide - Composting - Gas chromatography - Gases - Helium - Hydrogen - Liquid nitrogen  - Monitoring - Odor control - Particle size - Pollution - Radioactive waste disposal - Volatile organic compounds - Waste treatment - Wastes - Xylene
Uncontrolled terms:Agilent technologies - Correlation analysis - Emission concentration - Hydrocarbon compounds - Monitoring and control - Municipal solid waste (MSW) - Priority control - Sulfureted hydrogens
Classification code:943 Mechanical and Miscellaneous Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 941 Acoustical and Optical Measuring Instruments - 931.2 Physical Properties of Gases, Liquids and Solids - 804 Chemical Products Generally - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 801 Chemistry - 522 Gas Fuels - 454.2 Environmental Impact and Protection - 452 Municipal and Industrial Wastes; Waste Treatment and Disposal - 443.1 Atmospheric Properties - 723.1.1 Computer Programming Languages
DOI:10.3969/j.issn.1002-6819.2013.09.025
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 23>

Accession number:20132516429372
Title:Viscoelastic constitutive model of biomass pellet
Authors:Huo, Lili (1); Zhao, Lixin (1); Tian, Yishui (1); Yao, Zonglu (1); Meng, Haibo (1)
Author affiliation:(1) The Chinese Academy of Agricultural Engineering, Key Laboratory of Energy Resource Utilization from Agricultural Residues, Ministry of Agriculture, Beijing 100125, China; (2) The College of Engineer, China Agricultural University, Beijing 100083, China
Corresponding author:Meng, H.(newmhb7209@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:200-206
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Biomass resources such as agricultural and forestry wastes are very rich in China. Biomass can be compressed into a pellet and used instead of coal for heating, electricity, etc. Currently, the use of biomass pellets is being rapidly promoted. Not only can they be used for home cooking, heating, they can also be used as high-quality fuel for industrial boilers and power plants. Compared with coal, the greenhouse gas emissions of biomass pellet less than 1/9 of the coal, so these pellets have environmental benefits. This thesis research is about a biomass pellet molding viscoelastic constitutive model. The six kinds of biomass pellet raw materials which include corn straw, peanut shell, wheat straw, soybean straw, cotton straw and sawdust were the study objects densified by a 485 type roll pellet mill to analyze the stress change rules during the densifying process and measure the single feedstock of a biomass pellet by microscope in this paper. The densifying process of biomass pellets after feedstock was simulated and studied through a universal testing machine and self-made compress fixture when this is no raw material feed. The constitutive model was built for biomass pellets with viscoelastic theory to present the densifying mechanism for biomass pellets from the standpoint of mechanics, and the maximum stress and the energy consumption of the densifying process of the different species of raw material were compared and studied. The results showed that the viscoelastic constitutive model can be used to describe the densifying process of biomass pellets. A constitutive model of stress to strain can be adopted at the densifying process phase, and stress to time at stress relaxation phase. The fitting of a model curve is perfect and all coefficients of association are higher than 90%. Basically, the single feedstock for different raw material is the same, which is approximate 150 to 160 mg, while the densifying pellet density varies from each other which can be 1030, 1170, 1010, 1060, 1185, 1240 kg/m³ for corn straw, peanut shell, wheat straw, soybean straw, cotton straw and sawdust respectively. The maximum stress for the six kinds of raw material is that cotton straw and sawdust is higher, approximately 67 to 77 MPa, and the other 4 are between 45 and 55 MPa. The energy consumption of sawdust is the highest, which is 158 J/g, followed by cotton straw 91.4 J/g, peanut shell 86.9 J/g and soybean straw 65.5 J/g, and wheat straw and corn straw is much lower, which is 56.2 J/g and 45.1 J/g respectively. The biomass pellets' density is higher, and the energy consumption is higher which can be increased as fast as the increasing of density. This study results provide an important theoretical basis to solve the problem of the high-energy consumption of biomass pellets densifying manufacture, and ease the wear and short life of the key components of pellet mills.
Number of references:22
Main heading:Pelletizing
Controlled terms:Biomass - Coal - Constitutive models - Cotton - Curve fitting - Energy utilization - Feedstocks - Gas emissions - Greenhouse gases - Models  - Oilseeds - Stresses - Viscoelasticity
Uncontrolled terms:Biomass pellets - Biomass resources - Environmental benefits - Industrial boilers - Pellet - Universal testing machines - Viscoelastic constitutive models - Viscoelastic theory
Classification code:931 Classical Physics; Quantum Theory; Relativity - 921 Mathematics - 902.1 Engineering Graphics - 821.5 Agricultural Wastes - 821.4 Agricultural Products - 804 Chemical Products Generally - 803 Chemical Agents and Basic Industrial Chemicals - 802.3 Chemical Operations - 525.3 Energy Utilization - 525.1 Energy Resources and Renewable Energy Issues - 524 Solid Fuels - 451.1 Air Pollution Sources - 421 Strength of Building Materials; Mechanical Properties
DOI:10.3969/j.issn.1002-6819.2013.09.026
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 24>

Accession number:20132516429357
Title:Design and practice of rainwater utilization system for roof garden
Authors:Cao, Chuansheng (1); Liu, Huimin (1); Wang, Nan (1)
Author affiliation:(1) College of Horticulture, Northeast Agricultural University, Harbin 150030, China
Corresponding author:Liu, H.(liuhm0423@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:76-85
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In recent years, urban landscape has changed from ground greening to the roof three-dimensional greening with the rapid development of landscaping in China, and a lot of roof gardens have been built to open up the new development space for the landscape in cities. Shortage of water exists in many cities, and the city water stress will turn out because of the increasing roof gardens. To solve these problem, taking the roof garden of Beidahuang group hotel as an example, we would intend to discuss the feasibility of using roof rainwater for irrigating roof garden, and design the collection and utilization of the roof rainwater following the plant evapotranspiration (ET), the rainwater collection quantity, the reservoir capacity and rainwater collection systems. Firstly, the plant water requirement in roof garden was calculated using Penman-Monteith formula and garden coefficient methods. The results showed that the total of ET was 3521.78 m³ from May to October, and which was significantly different from only 361.8 m³ in October to 729.6 m³ in June. Secondly, the collection rainwater in roof garden and the next building roofs was calculated, it showed that the total collected roof rainwater was 2179.3 m³. The reservoir capacity was designed at 131 m³ according to the stormwater runoff volume and the first-flush runoff quantity. It could save 61.88% of irrigation water if the collected rainwater was used to irrigate for roof garden. Therefore, the rainwater collection systems and the automatic irrigation systems for the roof garden were designed using engineering technology. The rainwater collection systems included rainwater collecting ports, transporting pipelines, split-flow pool, purifying systems and reservoirs to collect rainwater in the roofs of the buildings, split-flow runoff, purify runoff rainwater, and store rainwater in the reservoir to use. Automatic irrigation system, included sensor system, central control system, power system, transporting system and communication equipments, the central control system could control the turn-on time and the irrigation quantity to the irrigation system by analyzing the soil moisture signals collected by the sensor system. So the automatic irrigation system could achieve accurate and water-saving irrigation. Finally, taking advantage of this automatic irrigation system could save 67.20% of irrigation water and the rainwater utilization rate was up to 54.55% with the water balance and running results analysis. The new recommendable method of roof garden rainwater collection and utilization proposed in this paper have the important practical value and the application prospects to design the technology for collecting and utilizing rainwater in the north arid area.
Number of references:32
Main heading:Roofs
Controlled terms:Arid regions - Control systems - Design - Evapotranspiration - Irrigation - Petroleum reservoirs - Plants (botany) - Rain - Reservoirs (water) - Runoff  - Sensors - Soil moisture - Water management - Water supply
Uncontrolled terms:Automatic irrigation systems - Communication equipments - Penman-Monteith equations - Plant water requirements - Rainwater collection system - Roof-garden - Water balance analysis - Water-saving irrigation
Classification code:446.1 Water Supply Systems - 461.9 Biology - 483.1 Soils and Soil Mechanics - 512.1.1 Oil Fields - 731.1 Control Systems - 801 Chemistry - 821.3 Agricultural Methods - 446 Waterworks - 402 Buildings and Towers - 408 Structural Design - 441.2 Reservoirs - 443 Meteorology - 443.3 Precipitation - 444 Water Resources - 444.1 Surface Water
DOI:10.3969/j.issn.1002-6819.2013.09.011
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 25>

Accession number:20132516429367
Title:Rural distribution network reconfiguration with dispersed generation
Authors:Gao, Yan (1); Yang, Rengang (1); Li, Wei (2)
Author affiliation:(1) College of Information and Electrical Engineering of China Agriculture University, Beijing 100083, China; (2) Beijing Electric Power Economic Research Institute, Beijing 100075, China
Corresponding author:Gao, Y.(taigemu7@sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:162-169
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:More and more Dispersed Generation has been interconnected with rural distribution networks and rural distribution networks commonly operate with a radial topology. Dispersed Generation is complicating the operation and protection schemes. But a radial distribution network is the basis of operation, protection schemes and dispatch in a rural distribution network. The models of distribution network reconfiguration should consider radial topology in their formulation. So the paper presented radial constraints in a mathematical model for a distribution network Reconfiguration and gave a preliminary analysis of radial constraints. Concerning an interconnecting Distributed Resource with an Electric Power System, mathematical models based on mixed integer nonlinear programming (MINLP) for the rural distribution network reconfiguration were built. The objective function was power losses of the distribution system. The binary nature of variables was proposed to represents the circuit between buses i and j connecting or not. Considering interconnecting with a substation for Dispersed Generation, a new constraint has been added to ensure that a distributed generator is not isolated from the substation. The mathematical model for distribution network reconfiguration problem was one in which the radial constraints were represented explicitly and showed that radial constraints can be considered in a simple and efficient way. With this method, distribution networks interconnecting as a Distributed Resource are still regarded as a passive termination of the distribution network with a radial structure. The paper proposed the use of a branch - bound method and Primal-dual interior point method to solve power dispatch and optimization reconfiguration problem of a distribution power system. The models of distribution network reconfiguration were formulated as a mixed integer non-linear programming (MINLP) problem. The MINLPIS relaxed, resulting in a set of non-linear programming (NLP) problems, which are solved at each node of the branch - bound tree through a Primal-dual interior point algorithm. The non-linear branch - bound algorithm proposed has special fathoming criteria to deal with non-linear and optimization reconfiguration models. The fathoming tests are redefined, adding a safety value to the objective function of each problem before they are fathomed through the objective function criteria, avoiding a convergence to local optimum solutions. From the result of the case study, it can be seen from the 33 nodes radial distribution test system that DG has the effects of a loss reduction improvement over feeders in the case, and the distribution system without DG are different from those with DG. With the increasing of capacity and numbers of DG, there has been a significant loss reduction and high efficiency of a distribution system with distributed generation (DG). The presented method has been compared with a GA algorithm based on the 54 nodes radial distribution test system The results show that solo transfer node can be identified by the presented method whereas by GA algorithm. The last case showed the total CPU time used by the branch - bound and Primal-dual interior point method and the number of binary variables for different test systems. The results showed that the presented method in this paper needs more time to obtain a global solution, but with the development of computer technology, the proposed method is a promising and effective tool for a distribution network with DG.
Number of references:20
Main heading:Branch and bound method
Controlled terms:Distributed power generation - Electric power system interconnection - Genetic algorithms - Geographical distribution - Mathematical models - Nonlinear programming - Power generation - Power supply circuits - Rural areas - Trees (mathematics)
Uncontrolled terms:Branch-bound method - DG - Distribution network reconfiguration - Fathoming tests - Primal-dual interior point methods
Classification code:922 Statistical Methods - 921.4 Combinatorial Mathematics, Includes Graph Theory, Set Theory - 921 Mathematics - 902.1 Engineering Graphics - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 723 Computer Software, Data Handling and Applications - 706.1 Electric Power Systems - 706 Electric Transmission and Distribution - 703.1 Electric Networks - 702 Electric Batteries and Fuel Cells - 615 Thermoelectric, Magnetohydrodynamic and Other Power Generators
DOI:10.3969/j.issn.1002-6819.2013.09.021
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 26>

Accession number:20132516429354
Title:Proportion optimization of ethanol-diesel fuel and engine performance test
Authors:Sun, Rui (1); Chen, Zhenbin (1); Li, Kaimian (2)
Author affiliation:(1) College of Mechanical and Electrical Engineering, Hainan University, Haikou 570228, China; (2) Tropical Crops Genetic Resources Institute, Chinese Academy of Tropical Agricultural Sciences, Danzhou 571737, China
Corresponding author:Chen, Z.(ebin1208@tom.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:55-63
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to improve the stability, effective thermal efficiency, and emission characteristics of a diesel engine fueled with ethanol-diesel blend fuel, this paper presented an experimental scheme and experimental procedures for the stability test of ethanol-diesel based on the DoE (design of experiment). The samples of ethanol-diesel were placed in the constant temperature test chamber. The temperature data was recorded when its phase separation occurred. A response surface model based on test data was constructed using the software Design-Expert and the software Isight. Resorting to the constructed model, the influence curves of alcohol, co-solvent to phase separation temperature was obtained and optimize preparation parameters of ethanol-diesel was optimized. The optimum proportion of ethanol-diesel was confirmed as the following: ethanol 10%, co-solvent 4%, and diesel 85%, and it could stay stable without phase separation in a plug tube at room temperature for 60 days. The load characteristic tests were carried out on diesel engine separately using the optimized ethanol-diesel and pure diesel. A comparative study of the engine rotate speed of 1500 r/min and 1200 r/min, the effective thermal efficiency, NO<inf>x</inf> and the smoke intensity were analyzed. From the result of the tests, the engine effective thermal efficiency of optimized ethanol-diesel was higher than pure diesel under middle and high load, but was similar to the low load. NO<inf>x</inf> emission of optimized Ethanol-diesel was reduced effectively under low load, and was slightly higher under middle and high load than that of pure diesel. In the full load condition, the NO<inf>x</inf> emission of both fuels was similar. Engine smoke intensity of optimized ethanol-diesel was similar in the low load conditions, but declined under middle and high load compared to that of diesel fuel. Furthermore, the variation of the effective thermal efficiency, NO<inf>x</inf> and the smoke intensity were studied by changing the fuel supply advance angle (19&deg;, 20.5&deg;, 23.5&deg; and 25&deg;). The results demonstrated that appropriately reducing the fuel supply advance angle would improve the fuel consumption and reduce the exhaust emission of ethanol-diesel.
Number of references:31
Main heading:Organic solvents
Controlled terms:Alcohol fuels - Curve fitting - Diesel engines - Diesel fuels - Emission control - Engines - Ethanol - Fuels - Optimization - Phase separation  - Smoke
Uncontrolled terms:Emission characteristics - Engine performance tests - Ethanol diesel blend fuel - Experimental procedure - Fuel supply advance angle - Phase separation temperatures - Response surface models - Thermal efficiency
Classification code:804 Chemical Products Generally - 803 Chemical Agents and Basic Industrial Chemicals - 641.1 Thermodynamics - 612.2 Diesel Engines - 921 Mathematics - 612 Engines - 523 Liquid Fuels - 522 Gas Fuels - 451.2 Air Pollution Control - 524 Solid Fuels
DOI:10.3969/j.issn.1002-6819.2013.09.008
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 27>

Accession number:20132516429363
Title:Study on nitrogen application rate tolerance based on rice yield and ecological security in hilly areas of South China
Authors:Chen, Anqiang (1); Lei, Baokun (1); Lu, Yao (1); Mao, Yanting (1); Zhang, Dan (2)
Author affiliation:(1) Agricultural Environment Resources Institute, Yunnan Academy of Agricultural Sciences, Kunming 650205, China; (2) College of Resources and Environment, Yunnan Agricultural University, Kunming 650201, China
Corresponding author:Lei, B.(bklei@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:131-139
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:To study the nitrogen application rate tolerance in the planting process of rice in the hilly areas of South China, and ensure the rice yield and ecological security and improve the nitrogen use efficiency, the relationships between nitrogen application rate, rice yield, apparent utilization rate of nitrogen, apparent loss of nitrogen and total nitrogen of surface water in paddy soil were analyzed through four field experimental points in Fujian (FJ), Sichuan (SC), Yunnan (YN) and Jiangxi (JX) provinces. The results showed that with the increase of the nitrogen application rates, the rice yields of every experimental point had the changes of quadratic function. The rice yields were the highest, which were respective 5.47, 11.24, 9.9 and 4.42 t/hm² when the nitrogen application rates of the experimental points of FJ, SC, YN and JX were 184.7, 185.98, 288.8 and 249.5 kg/hm². The apparent utilization rates of nitrogen had Sigmoidal functions descending relation to nitrogen application rates. The utilization rates of nitrogen slowly decreased when the nitrogen application rates were less. When the nitrogen application rates were more than 135, 155, 225 and 185 kg/hm² in experimental points of FJ, SC, YN and JX, the utilization rates of nitrogen rapidly decreased. There were exponential function growths between the total nitrogen of surface water in paddy soil and the nitrogen apparent loss of every experimental point. The total nitrogen of surface water in paddy soil slowly increased with the nitrogen apparent budget in at the beginning stage, and total nitrogen of surface water in paddy soil rapidly increased, which respectively increased by 50.9%, 53.3%, 90.6% and 93.4% when nitrogen apparent rates of FJ, SC, YN and JX were more than 180, 225.5, 270 and 236.3 kg/hm². The nitrogen application rate tolerance based on the principles of high rice yield, high nitrogen utilization rate and environment safety were confirmed by the analysis of the relationships of nitrogen application rate, rice yield, apparent utilization rate of nitrogen, apparent loss of nitrogen and total nitrogen of surface water in paddy soil. When the nitrogen application rates tolerance were respectively 135-184.7, 155-185.98, 225-236.3 and 185-249.5 kg/hm² in Fujian, Sichuan, Yunnan and Jiangxi provinces, the rice yields were accordingly 5.38-5.46, 11.19-11.24, 9.77-9.81, 4.36-4.42 t/hm². The study could provide a reference for the reasonable application amount of nitrogenous fertilizer in the process of rice cultivation.
Number of references:29
Main heading:Nitrogen
Controlled terms:Ecology - Experiments - Soils - Surface waters
Uncontrolled terms:Apparent loss - Nitrogen application rates - Paddy soils - South China - Utilization rates
Classification code:444.1 Surface Water - 454.3 Ecology and Ecosystems - 483.1 Soils and Soil Mechanics - 804 Chemical Products Generally - 901.3 Engineering Research
DOI:10.3969/j.issn.1002-6819.2013.09.017
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 28>

Accession number:20132516429358
Title:Volume replacement method for direct measurement of soil moisture and bulk density
Authors:Ma, Yuying (1); Lei, Tingwu (1); Zhang, Xinping (1); Chen, Yixin (1)
Author affiliation:(1) College of Hydraulic and Civil Engineering, China Agricultural University, Beijing 100083, China; (2) State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, Institute of Soil and Water Conservation, Chinese Academy of Science and Ministry of Water Resources, Yangling 712100, China
Corresponding author:Lei, T.(leitingwu@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:86-93
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Direct measurement of soil moisture and bulk density is the foundation of related research and applications, which is of great importance in such studies and applications as soil mechanics, crop production, irrigation and ecological environments. This paper presents a new method for direct measurement of soil moisture and soil bulk density based on volume replacement, which is equivalent to the conventional oven-dry method. The measurement principle is based on the model of soil three-phase composition, soil particles, water and air. Its volume and mass are partitioned into three fractions of these substances. The initial soil mass is approximately determined by the soil particles and water when the air mass is neglected. The measurement principles are as the follows. The samples used for measurements of moisture content and bulk density were taken by corers of known volumes and were weighted to determine their initial masses before they were filled with water to saturation state to replace all the air-filled spaces in the soil samples. The initial/original weight of the soil sample and that after saturation were used to compute the water mass required to replace the air-filled volume. Under the known soil particle density, the given volume as defined by the corer and the determined air-filled space volume, the original soil water content and soil bulk density can be calculated. An experimental system and the related algorithm procedures were proposed for the direct measurement of water content and soil bulk density. The standard soil corers were used to prepare the soil samples under designed bulk densities. The saturators were used to pre-saturate the soil samples. The samples were dripped with water to ensure their saturation during the measurement. Three soil materials, a clay loam from Yangling of Shaanxi province, a silt loam from Beijing and a red clay from Jiangxi province, were used for the demonstrational experiments to illustrate the measurement procedures and to verify the method. Seven different initial soil water contents, about 2%-3%, 5%, 10%, 15%, 25%, 30% and saturated water content, and three bulk densities of about 1.25, 1.35 and 1.45 g/cm³ were adopted in the experiments. These samples of the different initial water contents and soil bulk densities were used to measure the soil moisture by the volume replacement method. Detailed experimental procedures were presented to illustrate the experimental procedures. Conventional oven-dry method was used to determine parallelly the moisture contents of the soil samples similarly prepared. The water content changes when samples were oven-dried for 8, 12, 24, 48 h were measured to determine the influences of oven-dry period. The measured data showed that the soil water contents measured by the volume replacement were 2%-3% higher than those by the oven-dry method for a drying period of 8 h and were about 1% higher than those by the conventional oven-dry method for a drying period of 48 h. In addition, the traditional drying method is more time-consuming and not suitable for the field work. This indicates oven-dry method needs extended period of time to dry the soil sample. The results verify the newly-suggested measurement method and the experimental procedures. In general, the experimental operation of the volume replacement method is simple, time efficient, low energy consumption and high accuracy.
Number of references:24
Main heading:Soil surveys
Controlled terms:Cultivation - Density (specific gravity) - Drying - Energy utilization - Experiments - Geologic models - Measurements - Moisture determination - Ovens - Silt  - Soil mechanics - Soil moisture - Volume measurement - Water content
Uncontrolled terms:Ecological environments - Experimental procedure - Initial water contents - Low energy consumption - Measurement methods - Measurement procedures - Research and application - Soil bulk density
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 943.2 Mechanical Variables Measurements - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 944.2 Moisture Measurements - 901.3 Engineering Research - 444 Water Resources - 481.1 Geology - 483.1 Soils and Soil Mechanics - 525.3 Energy Utilization - 642.1 Process Heating - 821.3 Agricultural Methods - 822.1 Food Products Plants and Equipment
DOI:10.3969/j.issn.1002-6819.2013.09.012
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 29>

Accession number:20132516429376
Title:Nondestructive measurement of depths of earthing, canal lining and roadbed of reclamation projects
Authors:Wang, Xinjing (1); Hu, Zhenqi (1); Li, Enlai (1); Yang, Yaoqi (1); Zeng, Jiyong (1); Jiang, Zhidong (1)
Author affiliation:(1) Institute of Land Reclamation and Ecological Restoration, China University of Mining and Technology (Beijing), Beijing 100083, China
Corresponding author:Hu, Z.(huzq@cumtb.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:231-238
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The scope of damaged land caused by coal mining is increasing every year. For the sake of relieving the conflict between population growth and land availability, lots of land reclamation projects have been imposed in many provinces of China. However, the quality examination of those projects, which is considered as a key basic safeguard, always uses traditional methods. Few studies have reported on quick, non-destructive, and comprehensive engineering quality-testing methods. In order to overcome the deficiencies of quality inspection and evaluation in land reclamation projects, a variety of high frequency ground-penetrating radar GR-III systems has been used to detect the projects of covering, field canal and production road of the land reclamation in Ganshui town, Chongqing city, all the response characteristics of radar signal had been revealed. Using the energy changes of each sampling channel in different regions of radar image, the horizon identification algorithm was represented, which was used to resample the feature points of each horizon in different projects. On this basis, key factors of project quality, such as the depths of covering, field canal lining, and concrete pavement of production roads were calculated by different estimation methods using electromagnetic wave velocity, which were also considered as the indexes of the new evaluation model of reclamation project quality. The results show that GPR can realize nondestructive testing of land reclamation project quality and obtain comprehensive data. The detection effectiveness is positively correlated with the antenna's center frequency. The final evaluation result shows that qualities of the covering project and production road are class II and I, respectively. They meet the needs of farmland production, but the quality of field canal lining is class III, which must be thicker in later work. This study could provide a new way and a scientific basis for the evaluation of land reclamation project quality.
Number of references:21
Main heading:Quality control
Controlled terms:Algorithms - Canal linings - Coal mines - Electromagnetic waves - Ground penetrating radar systems - Land reclamation - Nondestructive examination - Population statistics - Project management - Radar measurement  - Roads and streets - Wave propagation
Uncontrolled terms:Estimation methods - Evaluation results - Ground Penetrating Radar - Identification algorithms - Non-destructive measurement - Quality inspection - Reclamation project - Response characteristic
Classification code:922.2 Mathematical Statistics - 921 Mathematics - 913.3 Quality Assurance and Control - 912.2 Management - 723 Computer Software, Data Handling and Applications - 716.2 Radar Systems and Equipment - 711 Electromagnetic Waves - 503.1 Coal Mines - 442.2 Land Reclamation - 434 Waterway Transportation - 421 Strength of Building Materials; Mechanical Properties - 406.2 Roads and Streets - 405 Construction Equipment and Methods; Surveying
DOI:10.3969/j.issn.1002-6819.2013.09.030
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 30>

Accession number:20132516429366
Title:Image processing method for detection of carrot green-shoulder, fibrous roots and surface cracks
Authors:Han, Zhongzhi (1); Deng, Limiao (2); Xu, Yan (2); Feng, Yonglian (4); Geng, Qichao (3); Xiong, Kai (2)
Author affiliation:(1) School of Geosciences, China University of Petroleum, Qingdao 266109, China; (2) Information College, Qingdao Agricultural University, Qingdao 266109, China; (3) University of Minnesota, Twin Cities, 55455 Minneapolis MN, United States; (4) Laixi Agriculture Bureau, Qingdao 266600, China
Corresponding author:Xiong, K.(yskxiong@sina.com.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:156-161
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:In order to improve the carrot automatic grading system based on computer vision, which refers to the grading standard of purchases and sales of carrots, this article proposed a detection method of carrot with green-shoulder, fibrous roots and surface cracks which impact the carrot appearance grading greatly. Five hundred and twenty carrots were selected randomly as testing samples, and their photos were taken by camera for the next step of processing and research. To detect the fibrous roots, the skeleton was extracted from the binary image after necessary image preprocessing and binariazation. Based on the fact that normal carrots have 5 end points of skeleton, fibrous roots are detected by computing the number of the skeleton end points. The number of fibrous roots is computed by subtracting 5 from the number of skeleton end points and then divided by 2, which is taken as the measure of whether there are fibrous roots on the carrot image. Green-shoulders of carrots can be distinguished by the green color which is very obvious on the R component image, so it is detected by thresholding the R component image of the carrot and computing the area of the green-shoulder region. The ratio of the area of the green-shoulder region and whole carrot region is defined as green-shoulder ratio to measure whether there is green-shoulder on the carrot. As for surface cracks, surface cracks are more obvious on S component images than on the other components, so they are detected by region marking on the S component image and computing the area of surface cracks. The ratio of the area of cracks and the whole carrot is defined as the degree of surface cracking to measure whether there are cracks on the carrot surface. For each carrot image, the three quantitative criteria mentioned above are computed for statistics and analysis, and then the detection accuracy rates of the three criteria are tested. The result show that the detection accuracy rate for the green-shoulder, the fibrous roots and carrot surface cracking defects detection are 97.5%, 81.8%, and 92.3%, respectively. It is showed from the result that the detection algorithms of green-shoulder and fibrous roots have higher accuracy rates than that of surface cracks and have reached above 92%. However, the detection results of cracks are not ideal because the color of cracks area is similar to that of the normal surface and are not obvious on the two-dimensional image. Finally, the detection rates of the three criteria are calculated synthetically. Result shows that the overall accuracy rate can reach 91.3%, which can meet the need of defect detection. The method proposed in this paper has positive significance for the research of carrot appearance quality grading system and product line.
Number of references:20
Main heading:Surface defects
Controlled terms:Computer vision - Crack detection - Cracks - Detectors - Grading - Image processing - Musculoskeletal system - Quality control - Two dimensional
Uncontrolled terms:Carrot - Fibrous roots - Green-shoulder - Image processing - methods - Quantitative criteria - Statistics and analysis - Surface cracks - Two-dimensional images
Classification code:914 Safety Engineering - 913.3 Quality Assurance and Control - 902.1 Engineering Graphics - 741.2 Vision - 741 Light, Optics and Optical Devices - 461.3 Biomechanics, Bionics and Biomimetics - 421 Strength of Building Materials; Mechanical Properties
DOI:10.3969/j.issn.1002-6819.2013.09.020
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 31>

Accession number:20132516429382
Title:Model of formula feed specific heat based on different components of feed ingredients
Authors:Wang, Hongying (1); Gao, Rui (1); Li, Junguo (2); Yang, Jie (1); Kang, Hongbin (1)
Author affiliation:(1) College of Engineering, China Agriculture University, Beijing 100083, China; (2) Feed Research Institute Chinese Academy of Agriculture Sciences, Beijing 100081, China
Corresponding author:Wang, H.(hongyingw@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:285-292
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:During the processes of conditioning, extrusion and cooling, the consistency and stability of feed products are the most important problems at present. In order to determine the heat and mass transfer properties of formula feed in these processes, the effects of different components of feed ingredients on specific heat were investigated using the continuous differential scanning calorimeter (DSC) method. With the help of a computer program, the apparatus provided different energy fluxes for the active cell containing texting sample and the reference cell containing air, in order to keep the two cells at the same temperature. By analyzing the energy differences between them, the specific heat of a sample could be obtained for the specific heat capacity of raw materials which had a great influence on the feed production. Up to now, there were many research reports on onefold raw material specific heat, however, the studies on formula feed specific heat were very limited. The works in this study took piglet formula feed as an example. The experiments in three factors with five levels were designed by a quadratic orthogonal rotation approach to attempt to determining the specific heat of the mixture of maize (46%-70%), soybean meal (9%-18%) and whey powder (2%-10%). Maize and soybean meal shared a larger proportion in piglet formula feed than other feed ingredients, while whey powder was a type of thermo-sensitive substance that had a great influence on specific heat. The result showed that the specific heat increased with an increase of heating temperature for each onefold raw material, but the whey powder appeared to peak at 58.8&deg;C, which may be the glass transition temperature of whey powder. This situation influenced microstructure and it was harmful to the nutritional quality of whey powder and the palatability of pellet feed. Based on the experiments, a model of specific heat of maize, soybean meal and whey powder mass fraction was established by regression analysis and response surface methodology (RSM).The results showed that the primary and secondary relations that influenced specific heat of formula feed were whey powder&gt;maize&gt;soybean meal, and those of interaction was maize&times;soybean meal&gt;maize&times;whey powder&gt;whey powder&times;soybean meal, and the regression equation was Y=2.63-0.022X<inf>1</inf> 0.052X<inf>2</inf> 0.011X<inf>3</inf>-0.011X<inf>1</inf>X<inf>2</inf> 0.026X<inf>1</inf>X<inf>3</inf> 5.687 &times; 10^-3X<inf>2</inf>X<inf>3</inf>- 0.046X<inf>1</inf>²- 0.017X<inf>2</inf>²-0.054X<inf>3</inf>² (R²=0.9822). (X<inf>1</inf> in mass fraction of maize; X<inf>2</inf> in mass fraction of whey powder; X<inf>3</inf> in mass fraction of soybean meal). The estimated result by the model revealed that the minimum specific heat of formula feed was 2536 J/(kg&middotK) under the mass fractions of maize, soybean meal and whey powder of 66%, 12%, and 6% respectively. The minimum specific heat of the formula feed was a benefit for energy conservation during the feed process and provided useful information for adjusting the machine parameters. The study was the first one to investigate the specific heat of formula feed, and came up with available information for the feed process of conditioning, extrusion, and cooling, which would have a good influence on the consistency and stability of feed products and provides a reference for the thermal processing of different formula feed.
Number of references:29
Main heading:Specific heat
Controlled terms:Differential scanning calorimetry - Experiments - Extrusion - Models - Oilseeds - Optimization - Regression analysis
Uncontrolled terms:Consistency and stabilities - Differential scanning calorimeters - Heat and mass transfer - Nutritional qualities - Piglet formula feed - Quadratic orthogonal rotation - Response surface methodology - Whey powders
Classification code:922.2 Mathematical Statistics - 921.5 Optimization Techniques - 902.1 Engineering Graphics - 901.3 Engineering Research - 821.4 Agricultural Products - 641.1 Thermodynamics - 535.2.2 Metal Forming Practice
DOI:10.3969/j.issn.1002-6819.2013.09.036
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 32>

Accession number:20132516429365
Title:Method of video segmentation for vegetable disease based on self-adaptive dual thresholds
Authors:Fu, Zetian (1); Su, Ye (1); Zhang, Lingxian (1); Li, Xinxing (1)
Author affiliation:(1) College of Information and Electrical Engineering, China Agricultural University, Beijing 100083, China
Corresponding author:Zhang, L.(zlx131@163.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:148-155
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:With the background of the rapid development of 3G communication technology, and the high popularizing rate of rural cell phones, this paper analyses the features of agricultural knowledge videos, which are currently in huge demand, but too big and too rough, and proposes the Method of Video Segmentation for vegetable disease based on self-adaptive dual thresholds. First, transform and quantify RGB video images based on HSV color space, and then divide the video with dual thresholds, which employs the self-adaptive threshold value to gain the best video segmentation threshold, and determine the abrupt and gradual transition by comparing the value of difference between frames and the threshold. Second, it's worth mentioning that in the measurement of frames, this method takes the segmentation strategy of different weighting factors, which excludes the influence of non-related content and makes the segmentation more precise. Finally, for the false-detected frames, because of the errors of threshold, an image similarity check method is suggested to revise the videos after segmentation, and combine the over-segmented ones, and finally output videos with continuous contents. This paper conducted an experiment on three videos about vegetable diseases, and compared the results in both histogram and dual thresholds, and reflected the effects with the rates of recall and precision. The experiment showed that the overall design of method of video segmentation for vegetable disease based on self-adaptive dual thresholds is able to segment videos quickly with a recall rate larger than 95% and a precision rate of 100%. Especially after the recheck in a similarity method, false-detection is almost distinguished. Compared to two other methods, it enhances the precision with similar segmentation time. So, this segmentation method ensures the precision rate without compromising the segmentation rate, and satisfies the information demands of specialized and individualized knowledge, and solves the conflicts of image quality and time, quantity and expense of net flow for farmers when they watch agricultural knowledge videos through their 3G mobile phones. Also, the method can provide a reference for other video segmentation of agricultural knowledge.
Number of references:28
Main heading:Image segmentation
Controlled terms:Agriculture - Algorithms - Cellular telephones - Diseases - Experiments - Mobile phones - Vegetables
Uncontrolled terms:Communication technologies - Gradual transition - Information demand - Recall and precision - Segmentation methods - Self-adaptive - Shot similarity - Video segmentation
Classification code:901.3 Engineering Research - 821.4 Agricultural Products - 821 Agricultural Equipment and Methods; Vegetation and Pest Control - 921 Mathematics - 723.2 Data Processing and Image Processing - 718.1 Telephone Systems and Equipment - 461.7 Health Care - 723 Computer Software, Data Handling and Applications
DOI:10.3969/j.issn.1002-6819.2013.09.019
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 33>

Accession number:20132516429373
Title:Catalytic cracking mechanism of bio-oil model compounds
Authors:Ma, Wenchao (1); Chen, Jiaojiao (2); Wang, Tiejun (1); Chen, Guanyi (2); Ma, Longlong (1); Zhang, Qi (1)
Author affiliation:(1) Key Laboratory of Renewable Energy and Gas Hydrate of Chinese Academy of Sciences, Guangzhou Institute of Energy Conversion, Chinese Academy of Sciences, Guangzhou 510640, China; (2) School of Environmental Science and Engineering, State Key Laboratory of Engines of Tianjin University, Tianjin University, Tianjin 300072, China
Corresponding author:Ma, L.(mall@ms.giec.ac.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:207-213
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Bio oil, produced by a fast pyrolysis of biomass, seems to be promising as the alternative to fossil fuel. However, bio oil has some undesired properties for fuel applications: high acidity, corrosiveness, low octane value, thermal instability, etc. These properties restrict its direct use for transportation, and require upgrading technology by reducing the oxygen content before use. Regarding to the complicated composition of bio oil, it is difficult to identify the reaction mechanism. Therefore, a model compound is widely used in bio oil upgrading research. Fluid catalytic cracking (FCC) experiments were performed in a quartz fluidized bed for a bio-oil model compound (acetol, ethyl acetate, guaiacol) over a HZSM-5 molecular sieve catalyst at 550&deg;C, aiming to study the cracking characteristics of model compounds and the reaction mechanism as well as catalyst deactivation properties. The FCC facility mainly consisted of a gas-supplying unit, a pre-heater, a fluidized bed reactor with an inner diameter of 4cm and a height of 50 cm, a two-step condenser, an accumulative flowmeter and a gas-collecting unit. Gas products were quantified by GC 9800, liquid products quantified and qualified by Agilent 7890/5973-GC/MS, coke deposition detected by TG-DSC (Netsch STA409PC). The liquid products of acetol cracking are composed of aromatics, phenols (&lt;5%), and hydrocarbons, while oxygen is released in the form of CO, CO<inf>2</inf>, H<inf>2</inf>O. The liquid product of ethyl acetate cracking is mainly aromatics (&gt;65%), oxygenated chemicals were less than 7%, and olefin content in the gas products is higher than 60%, which shows that the HZSM-5 has good selectivity of aromatics and olefins and has good deoxygenation properties. The liquid products of guaiacol are phenols (~50%), aromatics (~25%) and oxygenated chemicals (&lt;10%), which proves the stable structure of phenol. The catalytic liquid product of a model compound without aromatic rings contains mainly aromatics and a low content of oxygenated chemicals. The catalytic gaseous products for acetol and ethyl acetate are mainly CO and olefin, respectively. The main catalytic product of phenols are phenolic compounds, followed by aromatics, which means phenols have relatively stable structures, while the olefin gaseous products are around 30%. The coke deposition rate is acetol &gt; guaiacol &gt; ethyl acetate. According to the catalytic cracking products distribution, the catalytic reaction pathways is speculated to illustrate that deoxygenation and cyclodehydration take place over a bio-oil catalytic cracking reaction, and show a good selectivity of aromatics and olefins, which provides a theoretical basis for the bio-oil catalytic cracking mechanism study.
Number of references:26
Main heading:Cracks
Controlled terms:Alcohols - Aromatization - Biofuels - Biomass - Carbon dioxide - Catalysis - Catalytic cracking - Chemical reactors - Chemicals - Cracking (chemical)  - Deposition - Fluid catalytic cracking - Fluidized beds - Liquids - Mechanisms - Molecular sieves - Olefins - Petroleum transportation - Phenols - Quartz
Uncontrolled terms:Alternative to fossil fuels - Aromatics - Bio-oil model compounds - Cracking characteristics - Fluid catalytic cracking(FCC) - H-ZSM-5 - HZSM-5 molecular sieves - Model compound
Classification code:931.2 Physical Properties of Gases, Liquids and Solids - 804 Chemical Products Generally - 803 Chemical Agents and Basic Industrial Chemicals - 802 Chemical Apparatus and Plants; Unit Operations; Unit Processes - 601.3 Mechanisms - 525.1 Energy Resources and Renewable Energy Issues - 524 Solid Fuels - 523 Liquid Fuels - 482.2 Minerals - 433.3 Freight Railroad Transportation - 421 Strength of Building Materials; Mechanical Properties
DOI:10.3969/j.issn.1002-6819.2013.09.027
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 34>

Accession number:20132516429351
Title:Ergonomics evaluation method of tractor cab based on Pro/E Manikin
Authors:Yang, Fei (1); Shi, Qingchun (1); Wan, Xiaoling (1); Zhu, Sihong (1)
Author affiliation:(1) College of Engineering, Nanjing Agricultural University, Nanjing 210031, China
Corresponding author:Zhu, S.(zhusihong@njau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:32-38
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Ergonomics design is an essential part of the tractor cab design. This paper redefines the position of the Hip Point of a KT1804 tractor cab by the use of the United States SAE method on fixing a comfortable Hip Point, in combination with the recommended range of the signalized point of the tractor driver's seat known as SIP on GB/T6235-2004 "Sizes of driver's seat device in agricultural tractor". Referring to the fixed Hip Point, the KT1804 tractor cab was designed and arranged according to existing tractor ergonomics theoretical knowledge. Moreover, a three-dimensional model of the cab was established. Then the driver's sitting comfort, vision performance and the scope of manipulation were evaluated and simulated by using the Pro/E Manikin. The results show that each of the control devices cannot meet the needs of operator comfort at the same time. The cab is optimized in its layout and design. First of all, when the Hip Point coordinates location in the X direction are 550 and 581 mm, the fifth percentile and the ninety-fifth percentile of the Chinese male human body model are invoked and analyzed. When each control device used to manipulate comfort RULA analysis score is 1, the level range from the steering wheel, the gear lever, the side console and the front console to the AHP are 290-352, 366-437, 375-420 and 128-213 mm respectively. Secondly, whether the operating space would meet the requirements or not was checked by the situation of shadow area (command of enveloped and arrived) in the Pro/E Manikin module. Finally, in the process of the cab design, the muffler and air filter were located in the driver's vision blind field which was caused by the front vertical column. Moreover, two inevitable front vision blind fields on the horizontal plane (12.81&deg; and 14.36&deg;) were superimposed, reducing the vision blind field greatly. To a certain extent, the results of the analysis showed that the optimum design of the cab comfort, vision performance and operation were improved. At the same time, this study provides a basis for the ergonomic design of a tractor cab.
Number of references:28
Main heading:Tractors (agricultural)
Controlled terms:Aircraft seats - Control - Design - Ergonomics - Three dimensional - Tractors (truck)
Uncontrolled terms:Cab - Ergonomic design - Ergonomics design - Evaluation method - Human body models - Point coordinates - Pro/E manikin - Three-dimensional model
Classification code:902.1 Engineering Graphics - 732 Control Devices - 731 Automatic Control Principles and Applications - 663.1 Heavy Duty Motor Vehicles - 652.3 Aircraft Instruments and Equipment - 461.4 Ergonomics and Human Factors Engineering - 408 Structural Design
DOI:10.3969/j.issn.1002-6819.2013.09.005
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 35>

Accession number:20132516429379
Title:Pilot scale production process of micellar casein concentrate powder
Authors:Chen, Jianhang (1); Liu, Lu (1); Sun, Yanjun (1); Su, Yanling (1); Zhang, Shuwen (1); Kong, Fanpi (1); Jiang, Shilong (3); L&#252;, Jiaping (1)
Author affiliation:(1) Key Laboratory of Agro-food Processing, Institute of Agro-food Science and Technology, Chinese Academy of Agricultural Science, Beijing 100193, China; (2) College of Food Science and Engineering, North West Agriculture and Forestry University, Yangling 712100, China; (3) Heilongjiang Feihe Dairy Co., Ltd, Qiqihaer 161800, China
Corresponding author:L&#252;, J.(lvjp586@vip.sina.com)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:256-266
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:Micellar casein concentrate (MCC) powder, a new milk protein product produced by a combination of processes including membrane separation, evaporation and spray drying has potential applications in cheese making, whipped topping, coffee whitener and yogurt making. It is becoming more and more popular in the food processing industry, but currently China depends on imported MCC mainly from developed countries. The main objective of this study was to successfully develop a pilot scale production process for micellar casein concentrate powder and facilitate its rapid adoption and manufacturing in China's dairy plants. Preliminary studies involved the selection of a suitable hollow fiber ceramic membrane for the separation of casein micellar and serum protein between 100 nm and 40 nm pore size hollow fiber ceramic membranes (InoCep, Hyflux Ltd, Singapore). The 40nm pore size hollow fiber ceramic membrane, which had better separation performance, was chosen for further investigation on optimum operating parameters, mainly temperature and pressure. A four-stage diafiltration process was employed, in which chemical composition and flux changes were measured at the end of every stage in the production line. Finally, the micellar casein concentrate powder made after evaporation and spray drying process was compared with commercial MCC (Proteinco Inc., Quebec, Canada) in terms of their physical characteristics and chemical compositions. The yield rate and the production costs were also calculated. The results showed that: (1) the permeate of 100 nm pore size membrane was cloudy but the permeate of 40 nm pore size membrane was clear in appearance and the proportion of casein in the true protein of the permeate for the 100 and 40 nm pore size membrane were 40.03% and 17.48%, respectively. Therefore, the 40nm pore size membrane was found to be more suitable for the separation of casein micellar and serum protein and its average permeate flux during a 3&times;concentration at the optimal operating conditions (temperature 50&deg;C, pressure 2&times;10⁵ Pa) was above 60 L/(m²&middoth); (2) the best time for adding water during the whole diafiltration process was when the volume concentration factor was equal to 3, which reduced membrane fouling and enhanced average stage flux. After four stages of the continuous diafiltration process, the casein micellar purity and the pure protein content (on a dry basis) reached 93.34% and 88.15%, respectively; (3) at the end of the diafiltration process, the water flux declined by 39.98%, and when a biological-enzyme cleaning agent was used, water flux recovery was 98.02% of the initial; (4) The solubility of the pilot scale produced MCC was significantly different from that of the commercial MCC. The solubility was better in the pilot scale produced than commercial MCC, which may be due to the difference of the inlet temperature of spray drying. Additionally, the particle morphologies of the pilot scale-produced MCC, as observed by a scanning electron microscope, appeared spherical and smaller in size, whereas the commercial MCC had wrinkled particle surfaces and large particle sizes. (5) From the chemical analyses, determinations of total solids, lactose, minerals, total protein, true protein, casein protein and serum protein content were done but there were no significant differences (p&lt;0.05) between the pilot scale produced and the commercial MCC. (6) In order to produce 1 kg MCC, 46.24 L raw milk was required and the production cost of MCC was calculated as 244.58 Yuan/kg, which was deemed profitable and therefore can be transformed to the industrialized production stage. The methods and data stated in this study are valuable and useful to the industry and as a benchmark for further studies. They can also be used both as a reference and guide for MCC production in China.
Number of references:30
Main heading:Casein
Controlled terms:Body fluids - Ceramic membranes - Chemical analysis - Dairy products - Evaporation - Filtration - Food processing - Membrane fouling - Membranes - Microfiltration  - Phase transitions - Pore size - Production engineering - Profitability - Proteins - Scanning electron microscopy - Separation - Solubility - Spray drying
Uncontrolled terms:Food processing industry - Industrialized production - Micellar casein concentrate - Optimal operating conditions - Physical characteristics - Scanning Electron Microscope - Significant differences - Temperature and pressures
Classification code:913.1 Production Engineering - 911.2 Industrial Economics - 822.3 Food Products - 822.2 Food Processing Operations - 951 Materials Science - 804.1 Organic Compounds - 802.3 Chemical Operations - 801 Chemistry - 741.1 Light/Optics - 804 Chemical Products Generally
DOI:10.3969/j.issn.1002-6819.2013.09.033
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.

<RECORD 36>

Accession number:20132516429368
Title:Monitoring system for electrical conductivity of greenhouse nutrient solutions based on WSN
Authors:Li, Yinghui (1); Li, Minzan (1); Deng, Xiaolei (1); Sun, Hong (1); Zheng, Lihua (1)
Author affiliation:(1) Key Laboratory of Modern Precision Agriculture System Integration Research, Ministry of Education, China Agricultural University, Beijing 100083, China
Corresponding author:Li, M.(limz@cau.edu.cn)
Source title:Nongye Gongcheng Xuebao/Transactions of the Chinese Society of Agricultural Engineering
Abbreviated source title:Nongye Gongcheng Xuebao
Volume:29
Issue:9
Issue date:May 1, 2013
Publication year:2013
Pages:170-177
Language:Chinese
ISSN:10026819
CODEN:NGOXEO
Document type:Journal article (JA)
Publisher:Chinese Society of Agricultural Engineering, Agricultural Exhibition Road South, Beijing, 100026, China
Abstract:The application of hydroponics and a substrate-based culture in a greenhouse has been paid much attention to by more and more people for its environmental protection and high efficiency in the production. In order to promote automation of the soilless culture in a greenhouse, it is necessary to monitor the electrical conductivity (EC) of the nutrient solution used in greenhouse. Therefore, a monitoring system for EC of the nutrient solution in a greenhouse based on WSN was developed. The system consisted of a measurement section, a transmission control section, and a terminal server. The measurement section, including a conductivity electrode (DJS-1C) and a digital temperature sensor (DS18B20), could measure the EC and temperature of nutrient solution and then send the data to the transmission control section. The transmission control section could collect and process the data from different sensor nodes, and then display the result on the LCD screen to satisfy the needs of human-device interaction. It could also transmit the data of EC and temperature to the terminal server. The core controller of the whole system was a JN5139 module, which was responsible for collecting data in the measurement section, connecting with a GPRS module in the transmission control section through serial ports, and controlling GPRS by using AT commands. In this way, the system realized the remote transmission and management of soilless culture information. The data transmission was performed based on the IEEE802.15.4 standard and TCP/IP protocol. To save the consumption of power, the system was developed in a star network topology, combining with regular sleep and switches of the power of information collecting modules. Calibration tests were done in the laboratory to verify the accuracy of the system. Several estimation models were built and verified such as Piecewise linear model, Power function model, Logarithmic model, and Polynomial model. The results showed that the Piecewise linear model was the best choice, and the R² for fitting was greater than 0.97. In addition, experiments in greenhouse were conducted from June, 2012 to July, 2012 to monitor the EC of the nutrient solution of tomatoes. The precision reached to 0.01 mS/cm with a relative error of 2.10% and the range of the measurement was from 0.5 mS/cm up to 2.9 mS/cm. It was proved that the system could satisfy the requirements of real-time EC measurement in greenhouse.
Number of references:30
Main heading:Information management
Controlled terms:Data communication systems - Electric conductivity - Electric network topology - Greenhouses - Liquid crystal displays - Monitoring - Nutrients - Piecewise linear techniques - Sensor nodes - Standards  - Substrates - Wireless sensor networks
Uncontrolled terms:Digital temperature sensor - Electrical conductivity - Ieee802.15.4 standards - Information collecting - Nutrient solution - Piecewise linear models - Remote transmissions - Transmission control
Classification code:723 Computer Software, Data Handling and Applications - 731.1 Control Systems - 732 Control Devices - 801 Chemistry - 944 Moisture, Pressure and Temperature, and Radiation Measuring Instruments - 902.2 Codes and Standards - 941 Acoustical and Optical Measuring Instruments - 942 Electric and Electronic Measuring Instruments - 943 Mechanical and Miscellaneous Measuring Instruments - 903.2 Information Dissemination - 722.2 Computer Peripheral Equipment - 722 Computer Systems and Equipment - 402.1 Industrial and Agricultural Buildings - 461 Bioengineering and Biology - 461.9 Biology - 701.1 Electricity: Basic Concepts and Phenomena - 703.1 Electric Networks - 716 Telecommunication; Radar, Radio and Television - 717 Optical Communication - 718 Telephone Systems and Related Technologies; Line Communications
DOI:10.3969/j.issn.1002-6819.2013.09.022
Database:Compendex
Compilation and indexing terms, Copyright 2013 Elsevier Inc.