不确定性条件下的设备替换优化的 随机动态规划方法

本文提出了一种解决设备更新换代优化（ERO）问题的随机动态规划（SDP）模 型,用以明确地解释在车辆利用中的不确定性,并采用 Bellman 算法解决 ERO SDP 问题. 针对 SDP 状态空间的增长,提出了特殊简化算法,以解决动态规划方法中固有的“维数 灾”问题,确保所需的内存和计算时间不会随着时间范围的增加而成倍增长.并对 SDP 软 件的实现技术、功能和图形用户界面（GUI）进行了讨论,开发了基于 SDP 的 ERO 软件, 并使用美国得克萨斯交通局（TxDOT）现有车辆数据进行验证.对统计结果、软件计算时 间和求解效果进行综合分析,结果显示,使用该 ERO 软件,估计大量成本可以节省.     

EFFICIENT, INTEGRATED TRANSPORT SYSTEM KEY TO PORT''''S SUCCESS:Houston Sufficient support infrastructure, carrying capacity needed

An efficient, integrated transport system iskey to the Port of Vancouver s success. "There are many ways that we can optimizethe efficiency and carrying capacity of ourtransportation infrastructure in Canada: throughtechnology, by working together, by thinkingdifferently," said Captain Gordon Houston,President & CEO of the Vancouver Port Authority.     

Management Cybernetics: A New Institutional Framework for Coastal Management

This article analyzes institutional arrangements for the delivery of coastal programs through a new way of thinking about their evolution and structure. The notion of three distinct "dimensions" describing the phases in the evolution of institutional arrangements is introduced. The notion of dimensions is developed from conceptualizing about how institutional arrangements are diagrammed. This allows the visualization of how individual institutions and key stakeholders relate to each other in the delivery of coastal programs, how effective these relationships are, and how their relationships could be redesigned. "Dimensional thinking" enables the re-examination of existing institutional design of coastal programs and how these can evolve to meet the challenges of the new millennium. It is concluded that institutional arrangements have grown from a single dimensional view, where institutions (mainly governmental) delivered programs in isolation, through to the present second dimension where agency programs are managed through coordinating bodies and through coastal management plans. It is argued that a third dimension of institutional arrangements, one that recognizes and embraces the rapid pace of change in this century, will be needed that is aligned by themes rather than by organizational structure. To illustrate a third dimension a visualization tool is developed drawing from management cybernetics. It recognizes the increasing importance of formal and informal networks in relation to traditional modernist hierarchical management by recognizing multiple stakeholders (government at all levels, industry, advocacy groups, conservation interests, and the broader community) and their degree of mutual dependence. Dimensional thinking has the potential to institutionalize the interaction between these multiple stakeholders to ensure the effective delivery of coastal programs in the new millennium. A single answer to what the third dimension of coastal management program evolution should include is not presented. Rather, an approach is presented that allows coastal managers to move forward in the debate on redesigning coastal programs to meet today's complex suite of issues, values, and interests. An experimental case study from Western Australia is used to illustrate the potential application of the dimensional thinking to coastal management institutional design in that State's coastal program.     

2005FIGURES OF WORLD SHIPPING （CHINA）SUMMIT年会人物：EFFICIENT,INTEGRATED TRANSPORT SYSTEM KEY TO PORT＇S SUCCESS：Houston Sufficient support infrastructure,carrying capacity needed

An efficient,integrated transport system is key to the Port of Vancouver＇s success.     

Revisiting DDGX/DDG-51 Concept Exploration

This study revisits concept exploration for DDG-51 using reconstructed 1978–1979 DDX and 1979–1980 DDGX requirements and options, and 2005 tools. The goal of this study is to assess and highlight the benefits of current tools and processes for concept exploration by comparison with a well-known design that did not use these tools. This case study was completed in a summer and fall ship design project at Virginia Tech. In 1979, the acquisition and design process did not begin with a Mission Need Statement, Analysis of Alternatives or Integrated Capabilities Document as is required today. It began with studies, Tentative Operational Requirements, and Draft Top Level Requirements. In this study, we revisit the 1978–1980 DDG-51 (DDX/DDGX) concept exploration based on the guidance, goals, and constraints of the DDX and DDGX studies, using a notional mission statement, concept of operations, and list of required capabilities. The design space is defined to include many of the same design alternatives that were considered in the DDX and DDGX studies. A multiple-objective genetic optimization (MOGO) based on military effectiveness, cost, and risk is used to search the design space and perform trade-offs. A simple ship synthesis model is used to balance the designs, assess feasibility, and calculate cost, risk, and effectiveness. Alternative designs are ranked by cost, risk, and effectiveness, and presented in a series of non-dominated frontiers. Concepts for further study and development are chosen from this frontier and a comparison with DDG-51 is made based on these results.