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Space station short-term mission planning using ontology modelling and time iteration 被引量:4
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作者 Huijiao Bu Jin Zhang Yazhong Luo 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2016年第2期407-421,共15页
This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time ... This paper studies the problem of the space station short-term mission planning, which aims to allocate the executing time of missions effectively, schedule the corresponding resources reasonably and arrange the time of the astronauts properly. A domain model is developed by using the ontology theory to describe the concepts, constraints and relations of the planning domain formally, abstractly and normatively. A method based on time iteration is adopted to solve the short-term planning problem. Meanwhile, the resolving strategies are proposed to resolve different kinds of conflicts induced by the constraints of power, heat, resource, astronaut and relationship. The proposed approach is evaluated in a test case with fifteen missions, thirteen resources and three astronauts. The results show that the developed domain ontology model is reasonable, and the time iteration method using the proposed resolving strategies can successfully obtain the plan satisfying all considered constraints. 展开更多
关键词 space station mission planning ontology modelling time iteration
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A Flexible Multi-Layer Map Model Designed for Lane-Level Route Planning in Autonomous Vehicles 被引量:24
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作者 Kun Jiang Diange Yang +2 位作者 Chaoran Liu Tao Zhang Zhongyang Xiao 《Engineering》 SCIE EI 2019年第2期305-318,共14页
An increasing number of drivers are relying on digital map navigation systems in vehicles or mobile phones to select optimal driving routes in order to save time and improve safety. In the near future, digital map nav... An increasing number of drivers are relying on digital map navigation systems in vehicles or mobile phones to select optimal driving routes in order to save time and improve safety. In the near future, digital map navigation systems are expected to play more important roles in transportation systems. In order to extend current navigation systems to more applications, two fundamental problems must be resolved: the lane-level map model and lane-level route planning. This study proposes solutions to both problems. The current limitation of the lane-level map model is not its accuracy but its flexibility;this study proposes a novel seven-layer map structure, called as Tsinghua map model, which is able to support autonomous driving in a flexible and efficient way. For lane-level route planning, we propose a hierarchical route-searching algorithm to accelerate the planning process, even in the presence of complicated lane networks. In addition, we model the travel costs allocated for lane-level road networks by analyzing vehicle maneuvers in traversing lanes, changing lanes, and turning at intersections. Tests were performed on both a grid network and a real lane-level road network to demonstrate the validity and efficiency of the proposed algorithm. 展开更多
关键词 Lane-level ROUTE planning Tsinghua map model TRAVEL cost model
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Emergency Tasks Planning Based on Formal Modeling of Emergency Plan and HTN Planning System SHOP2 被引量:3
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作者 Jun Tian Zhi Li 《Intelligent Information Management》 2012年第6期357-363,共7页
A theoretical approach of ordered emergency tasks generation is proposed for dealing with a specific emergency event rapidly, exactly and effectively. According to the general principles of an emergency plan developed... A theoretical approach of ordered emergency tasks generation is proposed for dealing with a specific emergency event rapidly, exactly and effectively. According to the general principles of an emergency plan developed to response to an emergency management, a workflow model is employed to complete the formal modeling of concrete emergency plan firstly. Then the HTN planning system SHOP2 is introduced, the transformation method of domain knowledge from emergency domain to SHOP2 domain is studied. At last, the general procedure to solve the emergency decision prob-lems and to generate executive emergency tasks is set up drawing support from SHOP2 planning system, which will combine the principles (or knowledge) of emergency plan and the real emergency situations. 展开更多
关键词 EMERGENCY plan WORKFLOW model HTN planNING SYSTEM SHOP2 EMERGENCY Task
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The Multi-Scale Numerical Modeling System for Research on the Relationship between Urban Planning and Meteorological Environment 被引量:37
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作者 房小怡 蒋维楣 +7 位作者 苗世光 张宁 徐敏 季崇萍 陈鲜艳 魏建民 王志华 王晓云 《Advances in Atmospheric Sciences》 SCIE CAS CSCD 2004年第1期103-112,共10页
Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban sca... Considering the urban characteristics, a customized multi-scale numerical modeling system is established to simulate the urban meteorological environment. The system mainly involves three spatial scales: the urban scale, urban sub-domain scale, and single to few buildings scale. In it, different underlying surface types are employed, the building drag factor is used to replace its roughness in the influence on the urban wind field, the effects of building distribution, azimuth and screening of shortwave radiation are added, and the influence of anthropogenic heating is also taken into account. All the numerical tests indicate that the simulated results are reasonably in agreement with the observational data, so the system can be used to simulate the urban meteorological environment. Making use of it, the characteristics of the meteorological environment from the urban to urban sub-domain scales, even the among-buildings scale, can be recognized. As long as the urban planning scheme is given, the corresponding simulated results can be obtained so as to meet the need of optimizing urban planning. 展开更多
关键词 developing planning in an urban area meteorological environment multi-scale modeling urban planning urban environment
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Research on the Model of General Landscape Planning of City Road System 被引量:1
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作者 NIE Kangcai YAN Miao 《Journal of Landscape Research》 2014年第1期5-8,共4页
This paper analyses the overall landscape framework of city road system in ancient and modern China, using the ideal state terrain model which was fi rst recorded by the construction system of the Zhou Dynasty, and su... This paper analyses the overall landscape framework of city road system in ancient and modern China, using the ideal state terrain model which was fi rst recorded by the construction system of the Zhou Dynasty, and summarizes the ideal model of overall landscape framework of city road system, based on Chinese psychological needs of landscape, and conducts the applied research taking Nanchong in Sichuan, China for example. 展开更多
关键词 City road system General landscape planning model
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HEURISTIC MODELING FOR A DYNAMIC AND GOAL PROGRAMMING IN PRODUCTION PLANNING OF CONTINUOUS MANUFACTURING SYSTEMS 被引量:2
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作者 JAHAN A ABDOLSHAH M 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2007年第5期110-113,共4页
At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive... At the first sight it seems that advanced operation research is not used enough in continuous production systems as comparison with mass production, batch production and job shop systems, but really in a comprehensive evaluation the advanced operation research techniques can be used in continuous production systems in developing countries very widely, because of initial inadequate plant layout, stage by stage development of production lines, the purchase of second hand machineries from various countries, plurality of customers. A case of production system planning is proposed for a chemical company in which the above mentioned conditions are almost presented. The goals and constraints in this issue are as follows: (1) Minimizing deviation of customer's requirements. (2) Maximizing the profit. (3) Minimizing the frequencies of changes in formula production. (4) Minimizing the inventory of final products. (5) Balancing the production sections with regard to rate in production. (6) Limitation in inventory of raw material. The present situation is in such a way that various techniques such as goal programming, linear programming and dynamic programming can be used. But dynamic production programming issues are divided into two categories, at first one with limitation in production capacity and another with unlimited production capacity. For the first category, a systematic and acceptable solution has not been presented yet. Therefore an innovative method is used to convert the dynamic situation to a zero- one model. At last this issue is changed to a goal programming model with non-linear limitations with the use of GRG algorithm and that's how it is solved. 展开更多
关键词 Heuristic model Dynamic programming Goal programming production planning
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Preservation Planning in the OAIS Model 被引量:1
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作者 STEPHAN STRODL ANDREAS RAUBER 《现代图书情报技术》 CSSCI 北大核心 2008年第1期61-68,共8页
The OAIS model has gained widespread acceptance as the fundamental design reference model for an archival system by the digital library community. One of its core entities is Preservation Planning, for which central f... The OAIS model has gained widespread acceptance as the fundamental design reference model for an archival system by the digital library community. One of its core entities is Preservation Planning, for which central functional entities are given yet without every detail breaking down into activities requirements. The Planets Preservation Planning approach addresses this by providing a way to make informed and accountable decisions on which preservation strategy to implement in order to most suitably preserve digital objects for a given preservation context. It allows the explicit definition of requirements and goals and offers a systematic way to evaluate preservation strategies. This paper shows the implementation of the Develop Preservation Strategies and Standards function of the OAIS model through the Planets Preservation Planning approach. Moreover, the paper examines the information flows within the OAIS Preservation Planning entity and with other functional entities with respect to the Planets model. 展开更多
关键词 OAIS模型 数字资源 长期保存 保存计划 保存策略 图书馆
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Research on the Urban Agriculture Planning Models of Metropolis:A Case Study of Chengdu
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作者 QUE Yi WANG Haoyang 《Journal of Landscape Research》 2014年第5期22-25,共4页
With the accelerating urbanization, ecological environment of the city has attracted increasing attention, so the resulting problems have become key research focuses in all countries. Against this background, urban ag... With the accelerating urbanization, ecological environment of the city has attracted increasing attention, so the resulting problems have become key research focuses in all countries. Against this background, urban agriculture has been applied as one of the effective approaches for relieving urbanization. From the perspective of industrial form of urban agriculture, planning models of urban agriculture were explored, industrial form and planning model of Chengdu urban agriculture were analyzed to forecast its development prospects. Multi-dimensional development, and sustainable development measures were given to guarantee the sustainable development of urban agriculture. 展开更多
关键词 Urban agriculture Large city planning model Sustainable development Chengdu
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Derivation of Simplified Models of Plan View Pattern Control Function for Plate Mill 被引量:4
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作者 JIAO Zhi-jie HU Xian-lei ZHAO Zhong LIU Xiang-hua WANG Guo-dong 《Journal of Iron and Steel Research(International)》 SCIE EI CAS CSCD 2007年第4期20-23,共4页
The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to t... The plan view pattern control theoretical models were simplified. Under the condition of constant volume for the plan view pattern compensation, the relation between the thickness and the length can be simplified to the linearity in the segment for the plan view pattern control function. The compensation volume can be dispersed for easy calculation. By comparing the model calculation result with the actual result, it was concluded that the simplified model can be used for the online control process. 展开更多
关键词 plan view pattern control theoretical model simplified model
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Assessment of CDM Activities by a Generation Planning Model of the Chinese Power Grids 被引量:1
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作者 Akinobu Murata Eiichi Endo 《Journal of Energy and Power Engineering》 2012年第7期1022-1034,共13页
关键词 模型评估 CDM 发电规划 电网 中国 清洁发展机制项目 二氧化碳排放量 煤炭价格
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Nonlinear optimal model and solving algorithms for platform planning problem in battlefield 被引量:2
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作者 WANG Xun YAO Peiyang +1 位作者 ZHANG Jieyong WAN Lujun 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2018年第5期983-994,共12页
Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qu... Platform planning is one of the important problems in the command and control(C2) field. Hereto, we analyze the platform planning problem and present nonlinear optimal model aiming at maximizing the task completion qualities. Firstly, we take into account the relation among tasks and build the single task nonlinear optimal model with a set of platform constraints. The Lagrange relaxation method and the pruning strategy are used to solve the model. Secondly, this paper presents optimization-based planning algorithms for efficiently allocating platforms to multiple tasks. To achieve the balance of the resource assignments among tasks, the m-best assignment algorithm and the pair-wise exchange(PWE)method are used to maximize multiple tasks completion qualities.Finally, a series of experiments are designed to verify the superiority and effectiveness of the proposed model and algorithms. 展开更多
关键词 platform planning nonlinear optimal model Lagrange relaxation method m-best algorithm pair-wise exchange(PWE)
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Modeling Simulation Technology Research for Distribution Network Planning
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作者 Huanghuang Liu Dan Liu Qianjin Liu 《Energy and Power Engineering》 2013年第4期980-985,共6页
This paper proposes to use the power system simulation software CYME to plan, model and simulate for an actual distribution network for improving the reliability and efficiency, enhancing the efficiency and capacity, ... This paper proposes to use the power system simulation software CYME to plan, model and simulate for an actual distribution network for improving the reliability and efficiency, enhancing the efficiency and capacity, simulating the abnormal condition of distribution network, and presenting operation program of safe, reliable and having simulation record statements. The modeling simulation results show that the software module has lots of advantages including high accuracy, ideal reliability, powerful practicality in simulation and analysis of distribution network, it only need to create once model, the model can sufficiently satisfy multifarious types of simulation analysis required for the distribution network planning. 展开更多
关键词 DISTRIBUTION Network planNING modeling Simulation LOAD FLOW CALCULATION REACTIVE Power Optimization LOAD Balancing
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Non-smooth environment modeling and global path planning for mobile robots 被引量:6
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作者 邹小兵 蔡自兴 孙国荣 《Journal of Central South University of Technology》 2003年第3期248-254,共7页
An Approximate Voronoi Boundary Network is constructed as the environmental model by way of enlar-ging the obstacle raster. The connectivity of the path network under complex environment is ensured through build-ing t... An Approximate Voronoi Boundary Network is constructed as the environmental model by way of enlar-ging the obstacle raster. The connectivity of the path network under complex environment is ensured through build-ing the second order Approximate Voronoi Boundary Network after adding virtual obstacles at joint-close grids. Thismethod embodies the network structure of the free area of environment with less nodes, so the complexity of pathplanning problem is reduced largely. An optimized path for mobile robot under complex environment is obtainedthrough the Genetic Algorithm based on the elitist rule and re-optimized by using the path-tightening method. Sincethe elitist one has the only authority of crossover, the management of one group becomes simple, which makes forobtaining the optimized path quickly. The Approximate Voronoi Boundary Network has a good tolerance to the im-precise a priori information and the noises of sensors under complex environment. Especially it is robust in dealingwith the local or partial changes, so a small quantity of dynamic obstacles is difficult to alter the overall character ofits connectivity, which means that it can also be adopted in dynamic environment by fusing the local path planning. 展开更多
关键词 NON-SMOOTH modeling VORONOI DIAGRAM PATH planning GENETIC algorithm
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A Novel Robot Motion Planning Model based on Visual Navigation and Fuzzy Control
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作者 Xiaomin Wang 《International Journal of Technology Management》 2016年第9期58-60,共3页
关键词 模糊控制技术 视觉导航系统 机器人系统 规划模型 运动 模糊控制理论 操作系统 能量转换
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Comparative Geospatial Planning Model for “Location Specific” Intervention and Continuous Improvement Strategy
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作者 Princewill Ode Odum Nathaniel Olugbade Adeoye +1 位作者 Eleojo Oluwaseun Abubakar Marcus Aja Idoko 《Journal of Geographic Information System》 2016年第3期329-337,共9页
Sustainable development can only be achieved by conscious planning and implementation of action plans. Decision making requires a careful selection of the right conceptual framework and models for planning and impleme... Sustainable development can only be achieved by conscious planning and implementation of action plans. Decision making requires a careful selection of the right conceptual framework and models for planning and implementation processes. Planning process models dictate in very clear terms what must be done and how it is done to achieve a successful completion of a process of activity [1]. Since about 80% of data used to support decisions are geographically related [3], it is necessary to put Geographic Information Systems (GIS) at the core of the planning and implementation model. There exists a great disparity in a heterogeneous world. The locational disparity in achieving sustainable development, therefore, necessitates a planning model that is “location specific” i.e. identifies areas (locations) requiring intervention and areas (locations) requiring continuous improvement strategies. This was achieved in this study by reviewing Bell’s Information System Strategic Planning Model and Kaufman’s Strategic Planning Model, and the designing of new model to overcome the limitation of existing models. Practical application of the new model was carried out in education planning and administration in order to achieve the global goals for sustainable development 4 (quality education). Finding shows that the Comparative Geospatial Planning Model for “Location Specific” Intervention and Continuous Improvement Strategy is useful to support the achievement of sustainable development goals in multidisciplinary, multi-sector applicable instances. 展开更多
关键词 planNING model LOCATION INTERVENTION Improvement Sustainable Development Goals
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Towards Release Planning Generic Model: Market-Driven Software Development Perspective
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作者 Bassey Echeng Isong Obeten Obi Ekabua 《通讯和计算机(中英文版)》 2013年第4期443-450,共8页
关键词 软件开发 一般模型 市场导向 最佳组合 释放功能 开发过程 功能选择 市场驱动
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Application of Land-use Change Model in Guiding Regional Planning:A Case Study in Hun-Taizi River Watershed,Northeast China 被引量:11
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作者 LIU Miao HU Yuanman +3 位作者 ZHANG Wei ZHU Junjun CHEN Hongwei XI Fengming 《Chinese Geographical Science》 SCIE CSCD 2011年第5期609-618,共10页
This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) te... This paper firstly investigated the land-use and land-cover change (LUCC) in the Hun-Taizi River watershed, Northeast China from 1988 to 2004 based on remotely sensed images and geographic information systems (GIS) technology. Then, using the famous land-use change model of Conversion of Land Use and its Effects at Small regional extent (CLUE-S), this paper simulated the land use changes under historical trend (HT), urban planning (UP) and ecological protection (EP) scenarios considering urban planning and ecological protection over the next 20 years. The simulated results under UP scenario in 2020 were compared with the planning map to assess the feasibility of using land-use change model to guide regional planning. Results show that forest land, dry farmland, paddy, and shrub land were the main land-use categories. Paddy and dry farmland being converted to urban area and rural settlement characterized the land-use change from 1988 to 2004. The main land-use categories changed over time. Landscape-pattern fragmentation will be worse under HT and UP scenarios, but better in EP scenario. The comparing results of simulated map with planning map in 2020 show that land-use change model is powerful tool to guide regional planning. Land-use scenarios can support regional planning and policy-making through analyzing future consequences scientifically. 展开更多
关键词 土地利用变化 中国东北地区 区域规划 太子河流域 变化模型 浑河 应用 案例
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Cost-Benefit Assessment of Inspection and Repair Planning for Ship Structures Considering Corrosion Model Uncertainty
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作者 李典庆 唐文勇 张圣坤 《China Ocean Engineering》 SCIE EI 2005年第3期409-420,共12页
Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective... Owing to high costs and unnecessary inspections necessitated by the traditional inspection planning for ship structures, the risk-based inspection and repair planning should be investigated for the most cost-effective inspection. This paper aims to propose a cost-benefit assessment model of risk-based inspection and repair planning for ship structures subjected to corrosion deterioration. Then, the benefit-cost ratio is taken to be an index for the selection of the optimal inspection and repair strategy. The planning problem is formulated as an optimization problem where the benefit-cost ratio for the expected lifetime is maximized with a constraint on the minimum acceptalbe reliability index. To account for the effect of corrosion model uncertainty on the cost-benefit assessment, two corrosion models, namgly, Paik' s model and Guedes Soares' model, are adopted for analysis. A numerical example is presented to illustrate the proposed method. Sensitivity studies are also providet. The results indicate that the proposed method of risk-based cost-benefit analysis can effectively integrate the economy with reliability of the inspection and repair planning. A balance can be achieved between the risk cost and total expected inspection and repair costs with the proposed method, which is very. effective in selecting the optimal inspection and repair strategy. It is pointed out that the corrosion model uncertainty and parametric uncertaintg have a significant impact on the cost-benefit assessment of inspection and repair planning. 展开更多
关键词 ship structures inspection and repair planning COST-BENEFIT model uncertainty
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An Intelligent Master Model of Computer Aided Process Planning for Large Complicated Stampings 被引量:3
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作者 郑金桥 王义林 李志刚 《Journal of Southwest Jiaotong University(English Edition)》 2005年第2期103-112,共10页
Process planning for large complicated stampings is more complicated, illegible and multiform than that for common stampings. In this paper, an intelligent master model of computer aided process planning (CAPP) for ... Process planning for large complicated stampings is more complicated, illegible and multiform than that for common stampings. In this paper, an intelligent master model of computer aided process planning (CAPP) for large complicated stampings has been developed based on knowledge based engineering (KBE) and feature technology. This innovative model consists of knowledge base (KB), process control structure (PCS), process information model (PIM), multidisciplinary design optimization (MDO), model link environment (MLE) and simulation engine (SE), to realize process planning, optimization, simulation and management integrated to complete intelligent CAPP system. In this model, KBE provides knowledge base, open architecture and knowledge reuse ability to deal with the multi-domain and multi-expression of process knowledge, and forms an integrated environment. With PIM, all the knowledge consisting of objects, constraints, cxtmricncc and decision-makings is carried by object-oriented method dynamically for knowledge-reasoning. PCS makes dynamical knowledge modified and updated timely and accordingly. MLE provides scv. cral methods to make CAPP sysmm associated and integrated. SE provides a programmable mechanism to interpret simulation course and result. Meanwhile, collaborative optimization, one method of MDO, is imported to deal with the optimization distributed for multiple purposes. All these make CAPP sysmm integrated and open to other systems, such as dic design and manufacturing system. 展开更多
关键词 Large complicated stampings Process planning Knowledge-based engineering Intelligent master model
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Prediction on Cold Chain Logistics Demand of Urban Residents in Jiangsu Province during the Twelfth Five-Year Plan Period——Based on Estimates of GM(1,1) Model 被引量:2
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作者 ZHENG Yan-min1,ZHANG Yan-cai2,XU Hong-feng2 1.School of Economics and Management,Nanjing University of Science & Technology,Nanjing 210094,China 2.School of Economics and Management,Huaiyin Normal University,Huaian 223001,China 《Asian Agricultural Research》 2011年第11期38-40,45,共4页
This paper takes the total yield of products that need refrigerated transport as the impact factors of transport aggregate of cold chain logistics,such as meat,aquatic products,quick-frozen noodle,fruits,vegetables,da... This paper takes the total yield of products that need refrigerated transport as the impact factors of transport aggregate of cold chain logistics,such as meat,aquatic products,quick-frozen noodle,fruits,vegetables,dairy,and medicine.Through selecting the consumption data of urban residents on transported products via cold chain in Jiangsu Province from 2005 to 2000 as sample,this paper establishes grey prediction model GM(1,1) of cold chain logistics demand and uses DPS7.05 software for test,to predict the cold chain logistics demand of urban residents in Jiangsu Province during the Twelfth Five-Year Plan period.The results show that in the period 2010-2015,the cold chain logistics demand of urban residents in Jiangsu Province is 1 151.589 1,1 185.136 6,1 219.661 3,1 255.191 8,1 291.757 3,1 329.388 1 t respectively;in the period 2005-2010,the cold chain logistics demand of urban residents in Jiangsu Province increases at annual growth rate of 3.9%;in the period 2011-2015,the growth rate declines to some extent,increasing slowly at rate of 2.9%. 展开更多
关键词 COLD CHAIN LOGISTICS DEMAND The Twelfth Five-Year
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