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Are Intelligent Transportation Systems (ITS) affecting transportation industry only? ITS are currently perceived as a contribution to transportation industry only; however, by quantitatively analyzing the economic impact of ITS on the state of Michigan, this work attempts to answer the posed question. The quantitative economic analysis is carried out through the well‐established Leontief's Input–Output (I‐O) model. This model is employed to establish ITS effects on each industry by detailing RIMS II I‐O tables for Michigan constructed from the national I‐O tables. Major savings by ITS identified as reduced time delays and fuel cost savings are quantitatively simulated thereby generating an overall cost reduction factor which is incorporated in Michigan I‐O tables to modify their characteristics. ITS impact on each industry in I‐O tables is achieved by maximizing effects on certain selected industries. Impact multipliers that are customary macro‐economic measures for I‐O analysis are then calculated for all the aggregated industries. Multipliers comparison for the three cases namely before ITS implementation, conventional improvement methods, and after ITS implementation is evaluated. These values suggest greater economic benefits that may be achieved by statewide implementation of the ITS. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

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The late 1980s saw the first widespread use of Geographic Information Systems (GIS) in transportation research and management. Due to the specific requirements of transportation applications and of the rather late adoption of this information technology in transportation, research has been directed toward enhancing existing GIS approaches to enable the full range of capabilities needed in transportation research and management. This paper places the concept of transportation GIS in the broader perspective of research in GIS and Geographic Information Science. The emphasis is placed on the requirements specific of the transportation domain of application of this emerging information technology as well as on core research challenges.  相似文献   

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Urban freight transportation constitutes both an extremely important and a rather disturbing activity. Increasingly, one observes efforts to measure and control freight movements within city centers. We introduce a possible organizational and technological framework for the integrated management of urban freight transportation and identify important associated planning and operation issues and models. We then describe a formulation for one of these problems, the design of the proposed logistical structure, and discuss algorithmic and implementation issues. Our model city and challenge is Rome.  相似文献   

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We present a quadratic programming framework to address the problem of finding optimal maintenance policies for multifacility transportation systems. The proposed model provides a computationally-appealing framework to support decision making, while accounting for functional interdependencies that link the facilities that comprise these systems. In particular, the formulation explicitly captures the bidirectional relationship between demand and deterioration. That is, the state of a facility, i.e., its condition or capacity, impacts the demand/traffic; while simultaneously, demand determines a facility’s deterioration rate. The elements that comprise transportation systems are linked because the state of a facility can impact demand at other facilities. We provide a series of numerical examples to illustrate the advantages of the proposed framework. Specifically, we analyze simple network topologies and traffic patterns where it is optimal to coordinate (synchronize or alternate) interventions for clusters of facilities in transportation systems.  相似文献   

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Recent developments in intelligent transportation systems pose new challenges and opportunities for urban transportation planning. To meet these challenges and to exploit these opportunities, a framework for a new transportation planning methodology has been developed. The methodology operates in a computer environment, called PLANiTS (Planning and Analysis Integration for Intelligent Transportation Systems), designed to facilitate the entire planning process form problem identification, through idea generation and analysis, on to prioritization and programming. To assist in problem identification, PLANiTS provides graphic representation of current conditions, including traffic, air pollution, accidents, and projections of future conditions. A computerized knowledge base, containing information about possible strategies and their effects, and a model base, containing transportation and other analysis models, are used to guide the user in identifying potentially effective strategies and performing the appropriate analysis. To facilitate the use of these tools, PLANiTS provides computer support of group processes such as brainstorming, deliberation, and consensus seeking. PLANiTS is designed for use in urban transportation planning at the local, regional, and state levels; it is intended to support a variety of participants in the planning process including transportation professionals, decision makers in transportation agencies (often local elected officials), citizens, and interest groups. Recognizing that transportation planning is essentially a deliberative, political process, PLANiTS is designed to inform and facilitate, but not replace, the political decision-making process.  相似文献   

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The problem of distributing and routing vehicles in a large automated transportation network may be approached through the design of on-line control algorithms, particularly when the network contains many origin-destination pairs and alternate routes. To develop such algorithms, it is necessary to obtain models that accurately represent the dynamic behavior of vehicles on the guideway network. In this paper, models based on density, flow and average velocity variables are derived for the vehicle-follower longitudinal control scheme. Models suitable for use in analysis and simulation work are developed for links, merges, diverges, and stations. The proposed models are shown to compare favorably with simulation results that use explicit modeling of vehicle dynamic modeling of vehicle dynamic interaction.  相似文献   

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An information system is presented which identifies the transportation technologies suited to any one transportation need situation lying in a broad range of such situations. The system is concerned with people movement rather than goods movement. The user of the system specifies the nature and extent of demand, as well as certain service requirements. A transportation technology is identified as suited to a particular need situation when the technology meets the demand and the service requirements, and does so at reasonable cost. The technologies identified by the system as suited to a need situation must be examined to select the one best alternative. This final selection process is not part of the system. This system consists of two tables. Their use is described and examples are given. The procedure used to develop the tables is discussed. The system identifies new transportation technologies (PRT, AGT, etc.) as well as old.  相似文献   

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Transportation improvement site selection exemplifies transportation decision making that is collaborative in nature and geographically based. Such decision-making is part of a broad societal trend toward shared and participatory discussions about public investment. Perspectives from three different transportation decision contexts in the Puget Sound Region of Washington State, a regional council, a county government and a public–private Coalition group, are combined with a literature review to develop a decision task model that summarizes the need for information technology support during transportation improvement site selection. The task model guides the development of a decision support system requirement specification that outlines integrated information capabilities provided by geographic information system (GIS) and group support system (GSS) technologies. Together, GIS and GSS capabilities contribute to evolving group-based GIS. The kinds of capabilities a group-based GIS could offer in addressing the needs are identified. A report on the use of a prototype, group-based GIS called Spatial Group Choice highlights the possibilities in an inter-organizational coalition decision context. The conclusions discuss needs for future technology developments and social–behavioral science studies on these developments.  相似文献   

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This paper is concerned with the use of benefit-cost analysis to appraise investment in the construction of grade separations to eliminate or reduce highway traffic over existing rail/highway grade crossings. The paper deals with the measurement and valuation problems involved, and presents the results of a study of five grade separations authorised in Canada. A second issue considered is that of the determination of the appropriate apportionment of capital costs among the parties, rail and highway, involved. Alternative principles for determining who should bear the cost burden of grade separations are developed, and the implications of these cost apportionment procedures for the five Canadian case studies explored.  相似文献   

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The multidimensional nature of transportation output, makes the theory of multioutput production an adequate framework to analyze transportation activities from a microeconomic perspective. In this paper some concepts behind the theory of the multiproduct firm are identified within the context of their application to freight transportation according to the vector definition of output, and a synthesis of methodological procedures suggested by the scarce available experience on the estimation of multiproduct transportation cost functions is offered.  相似文献   

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Planning of sustainable transportation systems requires integration of multiple systems while considering a holistic approach. A limited amount of research has been conducted that simultaneously considers all the transportation, economic activity, environmental and social effects. The proposed research envisages incorporating considerations related to sustainability and providing solutions to stakeholders in policy making. In this paper, a dynamic model for planning and development of sustainable transportation systems is presented. This is given by a system of three nonlinear differential equations representing the dynamics of the three independent states, namely, transportation, activity, and environmental systems. A policy scenario considering investment in energy efficient technologies and its effects on the states is discussed to assist making investment decisions. Optimal control techniques are used to design the controls. The results show that it is possible to formulate an optimal control to achieve the desired target. Numerical results, based on actual parameters, are presented to illustrate the long-term trends of the states. The methodology discussed in this paper will be helpful to decision makers in making optimal decisions. The contribution of this research work is the introduction of a systems and controls methodology to develop optimal policies for the design of sustainable systems.  相似文献   

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A new transportation system is described. CyberTran is a steel wheel on rail system designed to travel on elevated guideways, utilizing large numbers of 6 to 20 passenger automated vehicles weighing less than 10,000 pounds. The benefits from these light weight vehicles include dramatically reduced system cost and increased passenger appeal. The system described has been prototyped and tested at the Idaho National Engineering and Environmental Laboratory, a U. S. Department of Energy Research and Development Laboratory.  相似文献   

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