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1.
This paper describes journey-planning procedures designed for use in a traveller information system covering fixed-schedule and demand-responsive public transport modes. The task is to construct a sequence of journey-legs to meet a traveller’s requirements with the least possible generalised cost, subject to time-window and other constraints. A journey may be carried out in a single leg by walking or by taking a taxi all the way from the origin to the destination, or by a sequence of one or more legs carried by public transport services sandwiched between walked segments connecting an initial pickup and final setdown stop. The public transport services may include fixed-route modes such as bus and train, and demand-responsive services running between fixed points. The main planning procedures are a high-level request-broker and a branch and bound procedure to handle multi-legged journeys; the request-broker also invokes a fleet-scheduling module to obtain bookings on demand-responsive services. The paper describes planning conditions, the planning procedures, and reduction techniques that are used to obtain acceptable computational performance. Tests with simulated demand suggest that the procedures are well suited for use in a real-time traveller information system.  相似文献   

2.
This article presents an overview of highway and transportation planning in England. It covers the division of responsibilities between central and local government; the organisation of the Department of Transport; the planning, financing and implementation of road schemes, both local and national. A very brief review of transport legislation is included.NOTE: This paper was printed before the UK General Election of May 1979. The Department of Transport is now responsible to the Minister of Transport. The Minister has similar responsibilities to those previously exercised by the Secretary of State for Transport as referred to in this paper. The views expressed in this paper are those of the writer and are not necessarily those of the Department of Transport.  相似文献   

3.
The implementation of transport infrastructure plans often has significant impacts on landscapes, especially where new roads and railroads are built. Key decisions regarding the building of new transport infrastructures are often made on a strategic level, where the long-term development of a region is determined, and before the infrastructure project actually begins. In this paper we build on previous advances in Strategic Environmental Assessment theory by linking the process-related issues of the integration of these assessments in general to landscape issues in particular; we use a multiple case study of Swedish transport planning.Results of this study indicate that the particular planning processes we looked at failed to carry out strategic landscape assessments and integrate landscape assessments in the planning process. We conclude that this can be explained by the flawed procedure of assessing landscape, the unhelpful structuring of SEA reports and by process-related issues. The idea of applying a holistic understanding of landscape, in line with the ELC, was notably absent from the studied cases. The lack of consideration of landscape as a whole can be attributed to poor use of dissipated and fragmented knowledge about landscapes as well as weaknesses in the assessment procedure. Our results indicate that the traditions of EIA are still prevalent in the practice of SEA, despite the fact that SEA theory has moved away from EIA-based methodology to become a tool for integrating environmental concerns into decision-making and for paying close attention to strategic decision processes.  相似文献   

4.
This paper uses the conjoint measurement technique for estimating the value of increased sailing frequency in inter-island transportation in Hawaii and the value of alternative queuing arrangements. The technique uses ordinal rankings of shipper preferences to estimate each shipper's utility function which, in turn, is used to estimate the change in consumer's surplus attribute to changes in service attributes.  相似文献   

5.
Within the transportation research literature, the attempt to understand and predict the level of car ownership is probably one of the most popular areas of study. The primary reason for this is understandable, having access to a vehicle increases an individual’s (or their household’s) travel options, leading to greater mobility. Secondary reasons for this scrutiny include the need to predict future transport investment in road infrastructure and the commercial demand for new vehicles. This paper attempts to predict the level of household car ownership as a function of the characteristics of the household and the individuals that make up the household. The primary data source for this study comes from the 2001 United Kingdom Census and the analysis methods used are from the discipline of data mining. The results of this study are in line with those from previous research but show a potential to predict the higher levels of household car ownership with greater accuracy than other similar studies.  相似文献   

6.
The supply of mass transport has not kept pace with the demand in cities in developing countries due to rapid urbanization and severe resource constraints. Developing countries would benefit from a study of the experience in developed countries regarding organization of mass transport and may adopt a few of the successful techniques. Examples include: unified transport authority; intermodal transfer facilities; subsidy to public transport; light rail transit; and redevelopment of the area around main rail terminals. Developing countries would be able to implement most of these techniques. The possible contribution of developed countries to developing countries lies mainly in the area of rolling stock and advanced signalling for rail based urban transport and in training highly skilled manpower for operation and management.  相似文献   

7.
Abstract

This paper presents a decision support methodology for long-range planning of transport systems that exhibits strategic flexibility and stochastic system parameters. Unlike one-off strategic decisions, flexible decisions should be dynamically reformulated with time. The proposed methodology is based on the construction of a tree structure of multiple interlinked tactical planning problems, each associated with a scenario in the tree, where problems under scenarios at intermediate dates incorporate in their formulation the solution of the corresponding problems associated with past (future) connected scenarios. The resulting tree structure of interconnected planning decisions becomes a strategic-tactical decision support system that allows managers to formulate suitable flexible strategic decisions that mitigate the consequences associated with downside scenarios while taking advantage of the upside opportunities. The methodology is applied to the planning of a fleet deployment through charter contracts where contract prices depend on both market behavior and the duration of the contract itself.  相似文献   

8.
The task of transport planning is to determine cost-effective methods of providing and improving mobility, which can include minimizing traffic congestion. A cost-effective solution to transport problems should consist of a land use pattern, a transport system an a set of road pricing policies that together bring demand and supply into balance in an efficient and equitable way. The conventional approach aimed to produce comprehensive, long-term plans for land use and transport in considerable detail, but tended to ignore the role of road pricing policy, thus ending up with solutions that might not be efficient or economical. This feature of sub-optimal road pricing policy is accentuated by the overall growth in car use, which has generated problems with the efficient use of road space. This paper presents a computer analysis system (or model) which will enable the analysis of coordinated tunnel toll pricing policies by optimising an “objective function” while satisfying the associated and other constraints. The possibility of integrating the optimal road pricing policies in the land use and transport planning are discussed. A case study based on Hong Kong data demonstrates the efficiency of optimizing tolls on two of the three harbour crossing tunnels in Hong Kong.  相似文献   

9.
10.
This paper aims to improve the understanding of the drivers of customer satisfaction with public transport (PT). The methodology provides a relevant contribution to the previous studies since it highlights the complex interaction between the level and composition of satisfaction, negative social safety experiences (NSSEs), urban settings, and the PT mode used.Overall, PT users see the service attributes on-time performance, travel speed, and service frequency as the most important, followed by personnel/driver behaviour and vehicle tidiness. A generic policy aimed at achieving these attributes may yield favourable results with respect to satisfaction.Further, we demonstrate the influence of differences in customer characteristics on satisfaction. A policy aimed at increasing the service frequency and putting new vehicles into operation will probably lead specifically to more satisfied older people (>65), passengers travelling by regional train, and people living in dense urban areas.These findings may be of help to PTAs intending to exert an influence on the actions of PT operators, for instance by using them as a measuring rod in incentive contracts.  相似文献   

11.
Historically, computer models have grown in complexity, and consequently have become more difficult to use. At the same time there is a growing need for quick-response methods and techniques for broad-brush policy formulation and decision making. The personal computer and its attendant software offer new means for quantitative sketch planning. This paper illustrates two PC-based applications for quick-response exercises. These involve interactive mapping and data analysis methods for the appraisal and interpretation of transport data, and the development and use of eclectic models for systems analysis and scenario generation. The LAMM and DIAMONDS packages are described, and their use in data analysis is illustrated. The Trends Integrator Procedure (TIP) is used to formulate a simple but versatile model for investigation of developments in an urban retailing system. These packages all run on PC's and offer powerful and adaptive tools for improved transport planning.Nomenclature a i a technical coefficient indicating the influence of the unique factor component (U i ) for factor F i - c ij a technical coefficient relating the influence of factor F i on factor F j - F i the relative change in the level of factor F i - U i the relative change in the unique factor component for F i   相似文献   

12.
Web-enabled public transport (PT) information systems that combine information on different PT modes, different PT companies and different geographical regions, can be built to improve the accessibility of public transportation. As the potential list of information aspects that can be included in such systems is long, it is interesting to examine the relative importance of different information aspects. This study reports the relative importance travelers attach to a range of information aspects. In addition, the willingness to pay for this information was examined by conducting a stated choice experiment, in which price was traded off against groupings of information aspects. The results of the study indicate that even though public transport travel information is highly price sensitive, travelers are willing to pay for it if the information systems provide additional functionality such as real-time information and, to a lesser extent, additional trip planning options.  相似文献   

13.
超?还是不超? 从经济学理论来说,货运企业(或车主、司机,下同)确定车辆装载量的动机,是企业运营利润的最大化.因此,他们会从主观上不断试图超出法定载货量的规定.但是,超载也有附加的成本,包括因超载而增加的营运成本和因超载而导致的罚款,也就是说,实施超载作业的运输企业,必须保证在超载利润和附加成本中取得平衡才会有钱赚.  相似文献   

14.
The estimation of semi-compensatory models is gaining momentum in transport planning in recent years. However, traditional survey methodologies focus on collecting solely compensatory choice data, which leads to information loss when semi-compensatory models are estimated. The present study proposes a novel web-based survey that enables collecting data about the entire semi-compensatory choice process. The web-based environment allows seamless tracking of semi-compensatory choice protocols without interfering with the natural choice process and without introducing problems related to comprehension bias, narrative inconsistency and misinterpretation of the choice protocols. The procedure is applied to rental apartment choice by students and results shed light on semi-compensatory choice by: (1) demonstrating the importance of choice set formation; (2) unravelling the distribution of threshold selection across the population; (3) revealing the linkage between the viable choice-set and the choice.  相似文献   

15.
This paper discusses a method to evaluate scheduled, fixed-route public transport. One major evaluation criterion in the method is total travel time, subdivided into walking time, waiting time, time on vehicle, transfer time, and concealed waiting time. The other major criterion is costs incurred by a given supply of transport. In contrast with conventional methods, this method operates with real measures, i.e. real location (instead of traffic zones), real time (instead of average travel time), and real costs (instead of proxy-costs). The purpose is to produce relevant and easily understandable results suitable to open planning, for instance planning with citizen participation. Five examples of application of the method are given: (1) evaluation of changes in suburban bus services; (2) evaluation of geographical localities as regards public transport; (3) evaluation of circular bus routes; (4) evaluation of flexible work hours versus fixed work hours and, finally; (5) production of user information on transport service.The research on evaluation of public transport was carried out in collaboration between Aalborg Municipality and the University of Aalborg 1980–1981. It was funded by the Department of Education, the University of Aarhus, Aalborg Municipality, the University of Aalborg's Data Centre and the University of Aalborg. The translation of this summary paper from Danish into English was funded and carried out by the Transport and Road Research Laboratories, Crowthorne, England.The paper summarizes: Bent Flyvbjerg, Kjeld Kahr, Peter Bo Petersen and Johs. Vibe-Petersen (1981).Evaluation of Public Transport — Method for Application in Open Planning. Vol. I & II. Aalborg University Press, Aalborg, 402 pp. In Danish.  相似文献   

16.
This research documents the primary strategies used by the US Congress to fund transportation earmarks from the early 1990s to the mid-2000s. It draws on careful analysis of funding bills and primary and secondary sources including government reports, industry and policy newsletters, scholarly articles, and publicly available data on earmarks. It is also informed by interviews with transportation stakeholders involved with earmarks at federal, state, and regional levels. By detailing how Congress pays for earmarks, I show that earmarks do more to redistribute than add to existing transportation resources, and that the intricacy of Congressional funding maneuvers can make earmarks’ fiscal impacts hard to discern. Several implications follow for transportation policy and practice. First, critiques that earmarks increase federal transportation spending are misplaced. While such claims make it easy to discredit national investment in transportation, skepticism is in order when earmarks are invoked to throw out the baby with the bathwater. Second, earmarks’ true costs are related not to increased deficits but rather to opportunity costs incurred when unplanned earmarks replace other investments, particularly projects identified through regional and state planning or competitive selection by an executive agency. Finally, this work suggests productive directions for future earmark reform, such as limiting earmarks to projects in regional or state plans and making explicit for any earmarks in a bill the funding mechanisms that support them. Such steps could lessen the opportunity costs (and administrative inefficiencies) of earmarks, increase transparency in earmarking, and potentially make the practice less objectionable if used to facilitate passage of the long overdue surface transportation authorization bill.  相似文献   

17.
Uncertainty of outcome is widely recognised as a concern facing decision-makers and their advisors. In a number of spheres of policy, it appears uncertainty has intensified in the face of globalisation, economic instability, climate change, technological innovation and changing consumer preferences. How can planners and policymakers plan for an uncertain future? There is growing interest in, and use of, techniques that can help decision-making processes where deep uncertainty is involved. This paper is based upon one of the most recent international examples of a foresight exercise employed to examine uncertainty – specifically that which concerns uncertainty over the nature and extent of future demand for car travel. The principal focus of the paper is on the insights and guidance this examination of uncertainty brings forth for transport planning and policymaking. To accommodate deep uncertainty requires a flexible and open approach in terms of how policy and investment possibilities are formulated and judged. The paper argues for a focus upon the Triple Access System of spatial proximity, physical mobility and digital connectivity as a framework for policy and investment decisions that can harness flexibility and resilience. Uncertainty becomes an opportunity for decision-makers with the realisation that they are shaping the future rather than (only) responding to a predicted future. The paper outlines two forms of policymaking pathway: regime-compliant (in which adherence to trends and the nature of the world we have known pushes policy) and regime-testing (in which the nature of the world as we have known it is brought into question and vision pulls policy decisions). Stronger orientation towards regime-testing to assist in managing an uncertain future is advocated.  相似文献   

18.
This paper presents a review and classification of traffic assignment models for strategic transport planning purposes by using concepts analogous to genetics in biology. Traffic assignment models share the same theoretical framework (DNA), but differ in capability (genes). We argue that all traffic assignment models can be described by three genes. The first gene determines the spatial capability (unrestricted, capacity restrained, capacity constrained, and capacity and storage constrained) described by four spatial assumptions (shape of the fundamental diagram, capacity constraints, storage constraints, and turn flow restrictions). The second gene determines the temporal capability (static, semi-dynamic, and dynamic) described by three temporal assumptions (wave speeds, vehicle propagation speeds, and residual traffic transfer). The third gene determines the behavioural capability (all-or-nothing, one shot, and equilibrium) described by two behavioural assumptions (decision-making and travel time consideration). This classification provides a deeper understanding of the often implicit assumptions made in traffic assignment models described in the literature. It further allows for comparing different models in terms of functionality, and paves the way for developing novel traffic assignment models.  相似文献   

19.
Implications of the difference between planned and market‐determined public transport services for the modelling of the transport system and its use are examined. In the former case, the task for government seeking to optimise performance of the transport system has a standard bi‐level form, but in the latter case, the lower‐level problem in the bi‐level formulation is to determine mutually consistent solutions to a pair of optimisation problems. The relevance of the mutually consistent solution in this context is contrasted with its sometimes misleading role in the context of optimisation of urban traffic signal control.  相似文献   

20.
The aim of this paper is to describe and apply a comprehensive framework to derive optimal and acceptable land use and transport strategies. The framework includes a constrained optimisation algorithm that approximates and maximises an objective function with respect to available land use and transport instruments and constraints. We apply the framework to Greater Oslo based on output from a land use and transport model for this area (RETRO). Available instruments are toll ring charges, public transport frequency and a discrete land use instrument. Constraints represent acceptable levels on the available instruments, and acceptable levels on equity between geographical zones, accident cost reductions and the financial balance of the actual strategy. Strategies are found in situations with increased and reduced fuel taxes, and the direct and indirect land use and transport effects of the optimal strategies are assessed.  相似文献   

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