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941.
物流网络选址与路径优化问题的模型与启发式解法 总被引:12,自引:5,他引:7
以商品从供应商,经过物流中心(或配送中心),配送到最终用户的整个过程中所产生的费用最小化为目标函数,提出了求解供应商的最佳位置与数量、配送中心的最佳位置与数量以及从配送中心到最终用户的最佳配送路径优化问题,建立了问题的数学模型,利用传统启发式算法与模拟退火法开发了问题求解的混合启发式解法,并利用人工生成数据和实例进行了计算验证。对于小规模问题,通过与数理规划软件所求得的最优解进行比较可以看出,所提出的数学模型可以准确地描述此类问题,所提出的混合启发式解法能够在短时间内求解问题,并得到非常接近于最优解的近似解;对于大规模问题,虽然无法求得最优解进行比较,但从实例计算结果来看,所求解也是较好的,因此可以认为所提出的解法是有效和良好的,具有较高的实用价值。 相似文献
942.
943.
船舶配电监测系统设计研究 总被引:1,自引:1,他引:0
针对船舶配电网络运行的监测手段和管理水平相对落后的问题,构建了船舶配电监测系统的结构形式,提出了配电监测系统设计方案,并对系统的组成和功能进行了说明。该系统采用集中数据管理,分层、分布式监测控制,采集全船配电网络的电量参数数据,通过CAN总线向系统终端传输,从而实现对全船配电网络实时集中监测和故障定位。 相似文献
944.
简述了工业管道输送流体流动特性,以及声发射技术在管道检测中的应用。采用手持式声发射检测仪器配合不同频率传感器对在役工业管道进行检测,研究焊接有三通、法兰、阀门等外接接口的不规则管道的定位特征,对比分析规则管道与焊有外接接口的不规则管道衰减特征区别,通过对现场数据的分析,得到管道损伤定位与传播声速之间的相互关系以及不同传播速度条件下产生的定位误差,综合分析误差产生原因,作为对现场检测的经验。 相似文献
945.
对上海松江区叶榭塘水利枢纽工程的特征参数、平面布置与主体结构型式及枢纽运行安全控制进行了详细的阐述。设计中对枢纽功能与环境景观的和谐统一、结构优化以及实现枢纽运行自动化控制方面有充分的考虑与尝试。 相似文献
946.
上海南站的综合交通换乘系统 总被引:5,自引:3,他引:2
详细介绍了铁路上海南站综合交通枢纽的总体布局和换乘系统,包括铁路与城市轨道交通、道路公交、出租车、自行车、私人小汽车、长途汽车、社会车辆之间,轨道交通与道路交通之间的各种换乘流线与换乘距离。通过分析比较得出:上海南站在换乘的布局设计上比既有的大型铁路客站有很多改进,但与国外优秀的交通枢纽布局设计相比仍有一些不足,主要是没有充分利用铁路股道下面的空间进行立体换乘。目前,我国城市交通枢纽尤其是城市综合交通枢纽的换乘问题日益突出,而枢纽换乘质量的关键取决于其布局设计方案的质量,该案例的分析结果对我国综合交通枢纽系统的布局规划设计有参考意义。 相似文献
947.
948.
Residential location,vehicle ownership and travel in Asia: a comparative analysis of Kei-Han-Shin and Kuala Lumpur metropolitan areas 总被引:1,自引:1,他引:0
The study examines the relationships between residential location, vehicle ownership and mobility in two metropolitan areas
of Asia, Kei-Han-Shin area of Japan and Kuala Lumpur area of Malaysia. It shows that, behind apparent similarities of household
auto ownership and travel time expenditure per household member, there are many causal relationships that are distinct between
the areas. The similarities and differences between the two areas point to the conjecture that the evolution of a metropolitan
area may be unique and path dependent, being heavily influenced by the history and culture of the locale, spatial and geographical
constraints, and historical progression in infrastructure development.
Metin Senbil is an Associate Professor in City and Regional Planning Department at Gazi University in Ankara, Turkey. He obtained the degree of Doctor of Engineering from Kyoto University, Japan. His research interests cover different aspects of urban travel demand and its interactions with telecommunications, land use, and policies directed at controlling as well as managing travel demand. Ryuichi Kitamura is Professor of Civil Engineering Systems at Kyoto University, Japan. His past research effort spans in the area of travel behavior analysis and demand forecasting, in particular in activity-based analysis, and panel surveys and dynamic analysis of travel behavior. He is associate editor of Transportation. Dr Jamilah Mohamad is Professor and Head of the Department of Geography, University of Malaya, Kuala Lumpur. Her main fields of research interest are travel behavior, the relationship between transport and spatial development and urban growth management. 相似文献
Jamilah MohamadEmail: |
Metin Senbil is an Associate Professor in City and Regional Planning Department at Gazi University in Ankara, Turkey. He obtained the degree of Doctor of Engineering from Kyoto University, Japan. His research interests cover different aspects of urban travel demand and its interactions with telecommunications, land use, and policies directed at controlling as well as managing travel demand. Ryuichi Kitamura is Professor of Civil Engineering Systems at Kyoto University, Japan. His past research effort spans in the area of travel behavior analysis and demand forecasting, in particular in activity-based analysis, and panel surveys and dynamic analysis of travel behavior. He is associate editor of Transportation. Dr Jamilah Mohamad is Professor and Head of the Department of Geography, University of Malaya, Kuala Lumpur. Her main fields of research interest are travel behavior, the relationship between transport and spatial development and urban growth management. 相似文献
949.
Identification of vehicle sensor locations for link-based network traffic applications 总被引:1,自引:0,他引:1
Shou-Ren Hu Srinivas Peeta Chun-Hsiao Chu 《Transportation Research Part B: Methodological》2009,43(8-9):873-894
Information on link flows in a vehicular traffic network is critical for developing long-term planning and/or short-term operational management strategies. In the literature, most studies to develop such strategies typically assume the availability of measured link traffic information on all network links, either through manual survey or advanced traffic sensor technologies. In practical applications, the assumption of installed sensors on all links is generally unrealistic due to budgetary constraints. It motivates the need to estimate flows on all links of a traffic network based on the measurement of link flows on a subset of links with suitably equipped sensors. This study, addressed from a budgetary planning perspective, seeks to identify the smallest subset of links in a network on which to locate sensors that enables the accurate estimation of traffic flows on all links of the network under steady-state conditions. Here, steady-state implies that the path flows are static. A “basis link” method is proposed to determine the locations of vehicle sensors, by using the link-path incidence matrix to express the network structure and then identifying its “basis” in a matrix algebra context. The theoretical background and mathematical properties of the proposed method are elaborated. The approach is useful for deploying long-term planning and link-based applications in traffic networks. 相似文献
950.