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Distribution of available soil water capacity in China 被引量:58
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作者 ZHOUWenzuo LIUGaohuan +1 位作者 PANJianjun FENGXianfeng 《Journal of Geographical Sciences》 SCIE CSCD 2005年第1期3-12,共10页
The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for m... The available soil water capacity (ASWC) is important for studying crop production, agro-ecological zoning, irrigation planning, and land cover changes. Laboratory determined data of ASWC are often not available for most of soil profiles and the nationwide ASWC largely remains lacking in relevant soil data in China. This work was to estimate ASWC based on physical and chemical properties and analyze the spatial distribution of ASWC in China. The pedo-transfer functions (PTFs), derived from 220 survey data of ASWC, and the empirical data of ASWC based on soil texture were applied to quantify the ASWC. GIS technology was used to develop a spatial file of ASWC in China and the spatial distribution of ASWC was also analyzed. The results showed the value of ASWC ranges from 15 × 10-2 cm3·cm-3 to 22 × 10-2 cm3·cm-3 for most soil types, and few soil types are lower than 15 × 10-2 cm3·cm-3 or higher than 22 × 10-2 cm3·cm-3. The ASWC is different according to the complex soil types and their distribution. It is higher in the east than that in the west, and the values reduce from south to north except the northeastern part of China. The "high" values of ASWC appear in southeast, northeastern mountain regions and Northeast China Plain. The relatively "high" values of ASWC appear in Sichuan basin, Huang-Huai-Hai plain and the east of Inner Mongolia. The relatively "low" values are distributed in the west and the Loess Plateau of China. The "very low" value regions are the northern Tibetan Plateau and the desertified areas in northern China. In some regions, the ASWC changes according to the complex topography and different types of soils. Though there remains precision limitation, the spatial data of ASWC derived from this study are improved on current data files of soil water retention properties for Chinese soils. This study presents basic data and analysis methods for estimation and evaluation of ASWC in China. 展开更多
关键词 available soil water capacity pedo-transfer functions China
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Multiproduct and multistage integrated production planning model and algorithm based on an available production capacity network 被引量:3
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作者 Zhi-min Lü Tian-ru Jiang Zai-wei Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第8期1343-1352,共10页
This research attempts to devise a multistage and multiproduct short-term integrative production plan that can dynamically change based on the order priority and virtual occupancy for application in steel plants. Cons... This research attempts to devise a multistage and multiproduct short-term integrative production plan that can dynamically change based on the order priority and virtual occupancy for application in steel plants. Considering factors such as the delivery time, varietal compatibility between different products, production capacity of variety per hour, minimum or maximum batch size, and transfer time, we propose an available production capacity network with varietal compatibility and virtual occupancy for enhancing production plan implementation and quick adjustment in the case of dynamic production changes. Here available means the remaining production capacity after virtual occupancy.To quickly build an available production capacity network and increase the speed of algorithm solving, constraint selection and cutting methods with order priority were used for model solving. Finally, the genetic algorithm improved with local search was used to optimize the proposed production plan and significantly reduce the order delay rate. The validity of the proposed model and algorithm was numerically verified by simulating actual production practices. The simulation results demonstrate that the model and improved algorithm result in an effective production plan. 展开更多
关键词 short-term integrated plan constraint satisfaction model available production capacity varietal compatibility virtual capacity occupancy
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Available capacity and robust wireless mesh connectivity of TDD-based networks
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作者 宋甲英 Li +2 位作者 Xu Zhong Zhangdui 《High Technology Letters》 EI CAS 2011年第1期80-85,共6页
This paper addresses the available capacity and robust connectivity of time division duplex based wireless mesh networks (TDD-based WMNs). A stochastic model is presented for TDD-based WMNs. Considering the paramete... This paper addresses the available capacity and robust connectivity of time division duplex based wireless mesh networks (TDD-based WMNs). A stochastic model is presented for TDD-based WMNs. Considering the parameters that affect the network performance like ratio of control slots number to data slots number, collision probability, node density and average hopcounts, the availa- ble capacity for each node is inferred. Meanwhile, the order of transmission range for robust connec- tivity of large scale WMNs is derived. With the stochastic model and inferred available capacity per node, the performance of TDD-based WMNs using IEEE 802.16 standard is analyzed under various conditions. Simulation results indicate that the available capacity of IEEE 802.16-based TDD-based WMNs and the theoretical result have the same increasing and decreasing trend as the node density increases. Simulation results also illustrate the optimal value of the ratio of control slots number to data slots number that maximizes the available capacity. 展开更多
关键词 wireless mesh networks (WMNs) TDD/TDMA performance analysis available capacity robust connectivity
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Assessment of several typical physical properties of reclaimed farmland filled with Yellow River sediment in Jining, China 被引量:5
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作者 Zhenqi Hu Peijun Wang +2 位作者 Russell S. Yost Fang Shao Linghua Duo 《International Journal of Coal Science & Technology》 EI 2018年第1期36-46,共11页
Land subsidence caused by underground coal mining is one of the most prominent environment problems in China. The reclamation of mining subsidence land with Yellow River sediment was considered to be feasible, but its... Land subsidence caused by underground coal mining is one of the most prominent environment problems in China. The reclamation of mining subsidence land with Yellow River sediment was considered to be feasible, but its effectiveness needs to be verified. An integrated reclamation technology with Yellow River sediment was evaluated using a comparison of actual crop production soil profile analysis in Jining City, China. The results indicated that reconstructed soil profile of the reclaimed farmland was less effective in retaining water and in supporting plant growth than that of the unaltered farmland. Some measures are proposed, such as reducing the drainage velocity to allow sedimentation and retention of the clay and silt, changing the techniques of filling the Yellow River sediment and increasing the organic matter content in the soil layers to improve the capacity to retain water in the reclaimed farmland. 展开更多
关键词 Yellow River sediment Mining subsidence land Land reclamation Soil physical properties Available water-holding capacity
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The Relationship Between Maintenance and Personnel Management In Industrial Companies
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作者 Zhao Songzheng School of Management Northwestern Polytechnical University Xi’an, 710072, P.R.ChinaK. Smit Faculty of Aerospace Engineering Delft University of Technology Kluyverweg1, 2629 HS Delft, 《International Journal of Plant Engineering and Management》 1996年第1期10-14,共5页
The Netherlands With the rapid development of computers and Management Information Systems(MIS), increasing number of factories have paid more attention to developing MIS, including provision for maintenance. But mai... The Netherlands With the rapid development of computers and Management Information Systems(MIS), increasing number of factories have paid more attention to developing MIS, including provision for maintenance. But maintenance systems in many organizations have been developed in a piecemeal fashion and often in isolation from other management systems . This paper describes the main relationship between maintenance and one of the maintenance resourcesPersonal. 展开更多
关键词 PERSONNEL Own Labor Third Party Gross Available capacity Nett Available Personnel capacity.
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Impact of Wind Power on the ATC Values in Hydro-Dominated Power System
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作者 Kresimir Fekete Goran Knezevic Ljubomir Majdandzic 《Journal of Energy and Power Engineering》 2014年第7期1293-1300,共8页
The wind power generation is increasing in many countries as a result of decreasing technology costs, active government policies for renewable energy sources, environmental concerns, etc.. This paper investigates the ... The wind power generation is increasing in many countries as a result of decreasing technology costs, active government policies for renewable energy sources, environmental concerns, etc.. This paper investigates the impact of wind power generation on ATC (available transmission capacity) calculation. In order to determine the maximum incremental MW transfer possible between two parts of a power system without violating any specified limits, ATCs are calculated. When calculating ATC values, it is necessary to assume production and consumption pattern in power system. Production of wind power depends on the wind speed, which is a random variable and it is impossible to forecast exactly the production of wind power that is needed for the ATCs calculation. In order to investigate influence of the stochastic wind power production on the ATCs value, computer model of Croatian electric power system is made in Power World Simulator. ATCs are calculated for southern part of Croatian power system in which besides wind power, hydro power plants are only type of power generation. Available wind speed measurements are used as input data for wind power production. The results of the ATC calculation for different scenario of wind power production and location in the Southern Croatian power system are presented and discussed in the paper. 展开更多
关键词 Available transmission capacity wind power hydro power computer model transmission system.
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Using a systems modeling approach to improve soil management and soil quality 被引量:2
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作者 Enli WANG Di HE +2 位作者 Zhigan ZHAO Chris J.SMITH Ben C.T.MACDONALD 《Frontiers of Agricultural Science and Engineering》 2020年第3期289-295,共7页
Soils provide the structural support, water andnutrients for plants in nature and are considered to be thefoundation of agriculture production. Improving soilquality and soil health has been advocated as the goal ofso... Soils provide the structural support, water andnutrients for plants in nature and are considered to be thefoundation of agriculture production. Improving soilquality and soil health has been advocated as the goal ofsoil management toward sustainable agricultural intensifi-cation. There have been renewed efforts to define andquantify soil quality and soil health but establishing aconsensus on the key indicators remains difficult. It isargued that such difficulties are due to the former ways ofthinking in soil management which largely focus on soilproperties alone. A systems approach that treats soils as akey component of agricultural production systems ispromoted. It is argued that soil quality must be quantifiedin terms of crop productivity and impacts on ecosystemsservices that are also strongly driven by climate andmanagement interventions. A systems modeling approachcaptures the interactions among climate, soil, crops andmanagement, and their impacts on system performance,thus helping to quantify the value and quality of soils.Here, three examples are presented to demonstrate this. Inthis systems context, soil management must be an integralpart of systems management practices that also includemanaging the crops and cropping systems under specificclimatic conditions, with cognizance of future climatechange. 展开更多
关键词 APSIM available water capacity nitrogen management soil functional properties soil health soil-plant modeling
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