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A preliminary theoretical model is developed for the mechanism of behavioural adaptations to changes in the road transport system, which describes the process of behavioural change, explains the nature of adaptation phenomenon, and predicts its effects on road safety programmes. It can be used as a basis to organize the body of adaptation research and to explain empirical results. 相似文献
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John Foster 《Transportation》1973,2(3):321-335
Existing methods of evaluating large-scale transport networks involve the use of mathematical models of traffic flow which are generally both large and complex. However, the time and cost involved in the use of these models normally restricts their use for the detailed forecasting of traffic flows and costs to the assessment of a relatively small number of alternative patterns of overall investment. In order to evaluate the individual projects and groups of projects which go to make up an overall investment plan, it is, therefore, usually necessary to make simplifying assumptions about the influence of any one project on the overall traffic pattern, so as to isolate it from the influence of neighbouring projects. These assumptions generally result in the loss of a certain amount of the detail normally available from a standard model, and the task of assessing the relative value of different projects and the amount of interaction between them is made more difficult.This paper describes a new technique, designed to permit the evaluation of individual projects whilst still retaining the level of detail available from a full-scale mathematical model. The aim has been to produce a cheap and easy-to-use technique, capable of producing substantially the same results as a standard model. The technique uses newly developed computer algorithms which short-cut the full-scale model by forecasting the changes in an existing travel pattern resulting from the influence of a particular project. Initial tests suggest that approaching the problem in this way can save up to 70% of the computing time and costs involved in the use of a standard model for the evaluation of individual projects.The technique as described here is envisaged as a tool for aiding strategic investment decisions. It can, however, provide data for more detailed investigations, and could, with modifications, carry out these investigations on smaller problems than those for which it was originally designed.Crown copyright reserved, 1973 相似文献
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This paper presents a general framework to estimate the bus user time benefits of a median busway including the effects on travel time and access time. Unlike previous models, we take into account the effects of geometry and the interaction with the demand structure. Models for predicting the bus in-vehicle time benefits of a median dual carriageway busway against mixed traffic condition on 2 and 3 lanes roads are estimated using data from a case study in Santiago (Chile), using a bus travel time model empirically estimated and considering different base case situations, including mixed traffic operations and bus lanes. Results of the application show that the expected in-vehicle time savings of a median busway might be reduced by access time losses due to increased walking distances and road crossing delays. Also, that net time benefits can vary significantly according to the base situation and the structure of demand considered. These findings point out to the need of including a wider set of impacts when studying the benefits of median busways, beyond in-vehicle time savings only. The empirical work presented here is completely based on passive data coming from GPS and smartcards, what makes easier and cheaper to conduct this type of analysis as well as to do it with a comprehensive scope at an early stage of the development of a BRT project. This framework can be extended to other types of dedicated bus lanes provided that a corresponding bus travel time savings model is available. 相似文献
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The case for including agglomeration benefits within transport appraisal rests on an assumed causality between access to economic
mass and productivity. Such causality is justified by the theory of agglomeration, but is difficult to establish empirically
because estimates may be subject to sources of bias from endogeneity and confounding. The paper shows that conventional panel
methods used to address these problems are unreliable due to the highly persistent nature of accessibility measures. Adopting
an alternative approach, by applying semiparametric techniques to restricted sub-samples of the data, we find considerable
nonlinearity in the relationship between accessibility and productivity with no positive effect to be discerned over broad
ranges of the data. A key conclusion is that we are unable to distinguish the role of accessibility from other potential explanations
for productivity increases. For transport appraisal, this implies that the use of conventional point elasticity estimates
could be highly misleading. 相似文献
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This paper examines all the disparate technologies and techniques capable of smoothing the integration of public transport modes and services at both the urban and interurban scale. The paper focuses on the application of information technology and telematics solutions which have been designed to create as seamless a journey as possible from the point of view of the transport system user. The scope of the paper is therefore deliberately wide‐ranging and includes an examination of measures as apparently unconnected as smartcard ticketing, bus priority systems, automatic vehicle locationing, trip planning and on‐board information systems as well as new public transport services offering demand responsive travel and integration with taxi services. The paper intends to show how such technological solutions can be used to increase the attractiveness and competitiveness of fixed public transport networks in comparison to the door‐to‐door flexibility of the private car. 相似文献
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《Transportation Research Part B: Methodological》1988,22(4):291-310
This paper presents an analysis of motorway circulation under congested traffic conditions, with the aim of arriving at a measurement of the reliability of the motorway transport system. The author suggests a model of the speed process on a motorway lane under conditions of congestion, which was tested experimentally employing a great number of data collected on two motorways, varying considerably in terms of environmental and traffic conditions. It is shown that the relationships between the parameters of this process and the traffic density define in sufficiently complete fashion the behaviour of the motorway transport system under conditions of congestion. Using this speed process model, a simulation procedure was developed which permits calculation of the reliability of a traffic stream. Finally a method was determined for calculating the reliability in real time, which can be usefully employed in motorway traffic control. 相似文献
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We study the effects of public transport use incentives on changes in travel satisfaction of participants that undergo behavior change. We use the results of an experiment conducted recently at the Massachusetts Institute of Technology and requiring a temporary use of public transport for commuting to work by habitual car drivers. We observe an increase in the average level of satisfaction with the commute to work of participants who switch to public transport after the temporary intervention. This increase is sustained to some extent several months after the intervention. Moreover, participants’ dissatisfaction is almost eliminated. We conclude that public transport use incentives are promising not only for encouraging sustainable travel behavior but also for increasing people’s satisfaction. 相似文献
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Tomoki Noguchi 《Transportation》1977,6(2):171-189
The urban areas in Japan have undergone rapid changes in the last two and one-half decades. At the same time, the urban transportation system has been faced with numerous problems which need to be solved urgently. This paper presents the development stage and problems in the three largest metropolitan areas, designated as transport spheres, in Japan. Japan's problems in urban transportation are similar to those of most Western nations with regard to such issues as rapid urbanization, growth in travel, increasing auto ownership, growing transit operating deficits, rising wages and air pollution. The differences are the large modal split of transit from automobile trips, major expansion of the rail transit network, and the large number of transit operators in each urban area in Japan. In addition, governmental policies to help solve the urban transport problems are briefly described. In order to make the policies effective, coordination among government agencies is required. The establishment of a unified government agency is regarded as the first priority in dealing with the urban transport problem. It is expected that the government will offer bold new countermeasures to cope with urban transportation problems.This report was accomplished with the kind assistance of Professor Jerry B. Schneider, Departments of Civil Engineering and Urban Planning, University of Washington, and Mr. Satoshi Inoue, an official of the Ministry of Transport in Japan, who is currently studying at the University of Washington. 相似文献
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ABSTRACTThe quality of traffic information has become one of the most important factors that can affect the distribution of urban and highway traffic flow by changing the travel route, transportation mode, and travel time of travelers and trips. Past research has revealed traveler behavior when traffic information is provided. This paper summarizes the related study achievements from a survey conducted in the Beijing area with a specially designed questionnaire considering traffic conditions and the provision of traffic information services. With the survey data, a Logit model is estimated, and the results indicate that travel time can be considered the most significant factor that affects highway travel mode choice between private vehicles and public transit, whereas trip purpose is the least significant factor for private vehicle usage for both urban and highway travel. 相似文献
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Bj⊘rn Andersen 《运输评论》2013,33(1):61-81
This paper surveys Swiss public transport structure and policy. The regulatory regime is explained with the division between the two operators working under federal monopoly — the State railways (SBB) and the postbuses (PTT) — and the rest of the system. The rather complicated Swiss subsidy arrangements are described. The federal government's emphasis on introducing cheap public transport fares on environmental grounds through the federal transport measures (BTM) and the use of cheap fares in urban areas are discussed. The paper notes the Swiss people's rejection by a referendum of a federal commission's proposal for an integrated transport policy, though some of the solutions were introduced in their own right: the division of SBB into two parts, and the creation of the concept Rail 2000, later developed into Rail + Bus 2000. Finally, the paper reviews problems of the Swiss policy, including the future of cheap fares, making some comparisons with developments in Scandinavia. 相似文献
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We consider a city region with several facilities that are competing for customers of different classes. Within the city region, the road network is dense, and can be represented as a continuum. Customers are continuously distributed over space, and they choose a facility by considering both the transportation cost and market externalities. More importantly, the model takes into account the different transportation cost functions and market externalities to which different customer classes are subjected. A logit‐type distribution of demand is specified to model the decision‐making process of users' facility choice. We develop a sequential optimization approach to decompose the complex multi‐class and multi‐facility problem into a series of smaller single‐class and single‐facility sub‐problems. An efficient solution algorithm is then proposed to solve the resultant problem. A numerical example is given to demonstrate the effectiveness and potential applicability of the proposed methodology. 相似文献
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道路运输质量指标体系用以反映道路运输行业相对水平和工作质量.它采用科学、客观、准确的指标,用先进的统计和分析软件,通过数据资料的搜集、整理和分析研究,能深入了解道路运输行业质量的现状和发展,指标数据能够转化为有用的管理信息的体系. 相似文献
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《Transportation Research Part A: Policy and Practice》2001,35(6):475-494
Recent earthquake disasters have caused major damage to transportation networks, leading to significant economic disruption. While this suggests the need to evaluate total system performance in transportation risk assessment, in addition to examining the vulnerability of individual components such as bridges, no appropriate measures currently exist. This paper develops post-disaster system performance measures and applies them to the urban rail and highway transportation systems in the Kobe, Japan, region devastated by the 1995 Hyogoken–Nanbu earthquake. Performance is evaluated in terms of network coverage and transport accessibility. Performance degradation was much more severe for highways and railways than for other lifeline infrastructure systems. Both transportation systems fared poorly in the disaster but service restoration proceeded much more rapidly for rail. The restoration of highway system performance correlated closely with the recovery of highway traffic volumes. The paper further develops a measure of subarea transport accessibility and applies this to Kobe’s constituent city wards. Results indicate substantial spatial disparity that is maintained throughout the restoration period. Comparisons with the 1989 Loma Prieta and 1994 Northridge earthquakes in the US show that although these disasters caused notable damage to highway bridges, system performance degradation was small in comparison with the Kobe experience. The paper argues that explicitly measuring transportation system performance can greatly facilitate both understanding the effects of historic disasters and preparing for future hazard events. 相似文献
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M. Pilar Socorro Ofelia Betancor 《Transportation Research Part A: Policy and Practice》2011,45(9):850-860
Air transport provides essential services in modern economies, though it produces significant negative external effects on the environment. Air quality, greenhouse gas emissions and noise are the main issues. The current environmental regulatory practice in air transport usually devises policy interventions for each externality in isolation disregarding their impact on the schedule delay, which in turn affects the consumers’ generalized price and social welfare. In this paper we develop a theoretical model that shows that such an approach is inadequate, and may lead to the choice of wrong environmental policies. 相似文献