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101.
J.H. Johnson 《Transportation Research Part B: Methodological》1984,18(2):87-100
The application of Q-analysis to road transport systems is introduced in this paper, but no prior knowledge of the methodology is assumed. It is argued that the route-link relation of transport systems has a connectivity structure overlooked by conventional transportation theory, and that this structure constrains traffic flow. This is illustrated at the micro-level by a complicated road intersection, and at the macro-level with a simple analysis of a town. The representation of road systems is discussed in this context, and it leads to a new result called the Link Face Theorem. It is suggested that the conventional theory can be usefully extended by studying the latent structure of road systems which is presently overlooked. 相似文献
102.
This paper describes the development of a computer model and algorithms for finding the time-dependent minimum path between two stations in a multi-route, multi-mode transit system running to fixed schedules. Selection of the minimum path can be based either on journey time or on weighted time. A worked example using a simple transit network is given to illustrate how the model works. The model has several applications in transport planning: it can be used for generating route schedule information to guide transit users, for assisting in route schedule coordination, and for analyzing transit system accessibility. 相似文献
103.
The paper considers traffic assignment, with traffic controls, in an increasingly dynamic way. First, a natural way of introducing the responsive policy, Po, into steady state traffic assignment is presented. Then it is shown that natural stability results follow within a dynamical version of this static equilibrium model (still with a constant demand). We are able to obtain similar stability results when queues are explicitly allowed for, provided demand is constant. Finally we allow demand to vary with time; we consider the dynamic assignment problem with signal-settings now fixed. Here we assume that vehicles are very short and that deterministic queueing theory applies, and show that the time-dependent queueing delay at the bottleneck at the end of a link is a monotone function of the time-dependent input profile to the bottleneck. We have been unable to obtain results when dynamic demand and responsive signal control are combined. 相似文献
104.
Performance indicators for transit management 总被引:1,自引:0,他引:1
Transit performance can be evaluated through quantitative indicators. As the provision of efficient and effective transit service are appropriate goals to be encouraged by federal and state governments, these goals are used to develop performance indicators.Three efficiency and four effectiveness indicators are described, together with two overall indicators. These nine indicators are analyzed for comparability utilizing operating and financial data collected from public transit agencies in California.Performance indicators selected for this study should not be viewed as final. Twenty-one performance indicators proposed by previous studies were reviewed. Theoretical considerations and unavailability or unreliability of data caused omission of several useful measures like passenger-miles. Circumstances such as improved data, emphasis upon goals other than efficiency and effectiveness, and local conditions might warrant the inclusion of indicators deleted from this research.This paper is based on work conducted for the Urban Mass Transportation Administration under University Research and Training Grant CA-11-0014, Development of Performance Indicators for Transit. The views expressed herein are those of the authors and not necessarily those of the University of California or the United States Government. We are indebted to John Feren for assistance with the statistical processing and data gathering. 相似文献
105.
106.
Using the concept of generalised costs to reflect quality in rail services, we consider the level of provision and quality of these services in the various forms they may take in a privatised environment within a model where we assume linear and separable demand and cost functions for analytical simplicity. Using the Pareto-efficient output and quality outcomes under a fully integrated system for reference (as well as those for a fully integrated profit-maximising monopolist) we show that if either bilateral monopoly or complementary monopoly emerge as a market structure the output of train services and their quality will generally fall. In the case of the emergence of both bilateral monopoly and complementary monopoly our analysis again suggests poor welfare outcomes. The implication that can be drawn from our analysis is that a regulator of a privatised rail system faces some severe problems if she is to attain the appropriate welfare targets. 相似文献
107.
The work described was undertaken as part of the CASSIOPE project in the EC DRIVE programme. A range of fare collection procedures in public transport is described, and the importance of these for data collection by operators is stressed. It is suggested that such data management could be standardized and to this end four case studies were carried out in different European cities. Data models were built for each city, and these models are merged into a preliminary version of a generalized model. The need and uses for such a fare collection data model is explained. 相似文献
108.
Using data on state highway expenditures and employment from 30 Minnesota non-metropolitan counties over a 25-year period, possible interactions between transportation and employment are investigated. While crosssectional analysis suggests no significant interactions, causality tests and time-series analyses indicate that highway expenditures affect manufacturing and retail employment, and employment influences expenditures. Although expenditure increases cause employment improvements in the short-term, long-term effects are less favorable. Highway expenditures respond quickly to increased needs caused by retail improvements. 相似文献
109.
This is the second of two background papers sponsored for the Symposium by the Administrative Commission for the north of the Netherlands. Its purpose is to provide an indication of the effects of the proposed high speed rail line between Amsterdam, Groningen and Hamburg on employment in the corridor. The authors first review the techniques of forecasting these effects discussed in the literature. The potentials approach is adopted for their analysis, the mathematics and underlying assumptions of which are presented. Finally, this model is run to provide an estimate of the impact on regional employment of three variants of the proposed rail line. 相似文献
110.
J. Edward Anderson 《先进运输杂志》1987,21(1):81-84
The choice of fare policy is more flexible in personal rapid transit than in conventional transit and has some unique aspects. The implementation of fare policies as a function of distance are discussed, and, following a discussion of how the fare would be collected in a PRT system, consideration is given to whether the fare should be per person or per vehicle. 相似文献