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1.
Macroscopic fundamental diagram (MFD) describes the macro relationship between a network vehicle density and a network space mean flow, without requiring the mastery of complex origin to destination data. Thus, MFD provides an opportunity for the macro control of urban road network. However, most of the existing MFD control methods ignore the active role of traffic guidance in solving congestion problems. This study presents a traffic guidance–perimeter control coupled (TGPCC) method to improve the performance of macroscopic traffic networks. The method considers the optimal cumulative volume of a network as the goal and establishes a programming function according to the network equilibrium rule of traffic flow amongst multiple MFD sub-regions, which regards the minimum delay of network, as the objective. The Logit model for the compliance rate of driver route guidance is established by the stated preference survey. Moreover, the perimeter control (PC) method is proposed for adjusting the phase split of intersections. Finally, three schemes, namely, the TGPCC, PC and the method without PC and guidance are tested on a network with four well-defined MFD sub-regions. Results show that the TGPCC addresses the issue of congestion and decreases the total delay accordingly.  相似文献   

2.

Traffic signal control is one of the oldest applications of fuzzy logic, at least in transportation engineering. The aim of this paper is to present a systematic approach to fuzzy traffic signal control and to derive the linguistic control rules based on expert knowledge. Traffic signal programming is generally divided into two problems: firstly, the choice and sequencing of signal stages to be used, and secondly, optimizing the relative lengths of these stages. The rule bases for both problems are introduced in our paper. The results of tested rule bases and field tests of fuzzy control have been promising. The fuzzy signal control algorithms offer better measures of effectiveness than the traditional vehicle‐actuated control.  相似文献   

3.
Public transport in Britain has traditionally operated under conditions of regulation. The 1930 Road Traffic Act imposed controls upon the quantity and quality of transport regulations, with an abolition of the quantity controls associated with inter‐city coach services. The principal objectives of the Act were to eliminate restriction upon entry to the market and to promote competition between coach operators.

This paper is based on research which was undertaken to establish the impact of the 1980 Transport Act upon express (inter‐city) coach services in Britain. The effects of the legislation are examined in relation to the experience of various coach operators, British Rail, and the inter‐city traveller. This provides evidence of the way in which the supply of, and demand for, public transport behaves in a competitive, deregulated environment. It is shown that at least in net terms, the consumer has enjoyed short‐term benefits. Greater uncertainty surrounds the long‐term situation. The main competition has been confined to the principal trunk routes and has taken place between the state‐owned undertaking of National Express and British Rail. The outcome of deregulation for the private sector has been disappointing.

The paper identified similarities which exist between inter‐city and local public transport services. In this context, the lessons derived from express deregulation are employed to suggest likely developments in the deregulation of stage carriage (local) services in Britain.  相似文献   

4.

Much PRT development and research is currently being undertaken assuming quasi‐synchronous longitudinal control of guideway vehicles. This method of control has the characteristic that intersection performance has a substantial influence on the efficiency of trip demand processing. An algorithm for the control of a PRT intersection is discussed here, which would appear to have significant advantages over all other known existing stratagems. The stratagem is not only efficient but its flexibility facilitates tailoring to diverse local conditions; furthermore, the algorithm does not require intractable computations or excessive computer memory requirements. The algorithm is described and simulation results are presented. A comparative study is also made between this algorithm and its fore‐runner.  相似文献   

5.
Internationally, recent years have seen a spread of deregulatory policies with respect to transport. Equally, transport movements across national boundaries have expanded as trade has grown. Despite these two quite noticeable trends comparatively little has been written on the problems that are created for cross‐border traffic as the result of differential changes in national regulatory policies. This paper is concerned with looking specifically at what has happened in the context of road freight transport movements across the U.S.‐Canadian border and the wider (especially for the formulation of a Common Transport Policy for the EEC) lessons which can be learned from it.  相似文献   

6.

Over the last ten years, there has been considerable interest in a number of countries in the accessibility and mobility problems of the transport disadvantaged particularly the elderly and the handicapped. The authors summarize the rationale that has been used in the examination of needs and demand and in the provision of infrastructure in the form of vehicles and installations. The paper outlines some of the more important policies relating to the United States, Great Britain, France and a number of other countries.  相似文献   

7.
As an important measure to abate ship-source air emissions, the establishment of Emission Control Area (ECA) has been adopted not only at international level, but also at national and regional level. However, there exists a research gap of employing econometric models to enrich the ECA policy evaluation research by testing the effectiveness of an ECA policy based on the empirical data. This paper focuses on the effectiveness of the ECA policy in shanghai port by adopting regression discontinuity (RD) approach. The RD design is considered as a wonderful substitution for the randomized control trial, which usually serves as a conventional and effective tool to address endogeneity. The causal effect of the ECA policy on the SO2 concentration reduction can be detected by the RD approach. According to the estimated results, there is a discontinuity around the ECA policy cutoff point, and it is indicated that the SO2 concentration in Shanghai decreased by at least 0.229 μg/m3 daily on average due to the implementation of the ECA policy. The positive role that the ECA policy plays in reducing SO2 concentration in Shanghai is well demonstrated. This paper also puts forward an agenda for the future studies in the domain of the ECA policy evaluation.  相似文献   

8.
Abstract

This study empirically investigated service quality, switching costs and customer loyalty from home‐delivery services' customers' perceptive. With regard to service quality attributes, findings indicated that customers were most satisfied with ‘range of delivery’, followed by ‘seldom loses parcels’, ‘invoice accuracy’, ‘prompt and reliable collection’ and ‘delivery by due time’. They were least satisfied with competitiveness of price. A structural equation modelling (SEM) approach was employed to analyse the impact of service quality and switching costs on customer loyalty from customers' perspective. Results revealed that service quality positively influenced switching costs and customer loyalty, and switching costs had a positive effect on customer loyalty. Investigation of the moderating effect of switching costs on the relationship between service quality and customer loyalty indicated that it was significantly important. Theoretical and practical implications of the findings for firms providing home‐delivery services are discussed.  相似文献   

9.
Abstract

Middle‐class expansion and new consumption patterns have increasingly become an important focus of studies of the development and change in newly industrialized and middle‐income‐developing East and South East Asian countries. However, there is still a dearth of studies in the literature particularly focusing on middle‐class travel patterns, predispositions and transport policy preferences. Nor have the implications of these factors on current transport and land development policy been examined. The present exploratory study addresses this gap by examining three cases in Bangkok, Thailand, which in recent decades witnessed dramatic middle‐class expansion, an increase in private motor vehicle population, and spatial diffusion of middle‐class residences into lower‐density zones in the suburbs. By mainly employing a survey method of data‐gathering and quantitative research analysis, the paper discusses the following findings: (1) that middle‐class travel behaviour is characterized by a high dependence on private motor vehicle travel and ‘inward commuting’; (2) that middle‐class preferences for transport mode and attitudes about remedial policy options are generally protective of their members’ car‐dependence and ownership; and (3) that present policy measures of the Thai government on Bangkok transport perfectly fit and support exclusively middle‐ and upper‐class predispositions and stakes in mobility. These findings in a developing country city basically follow a similar profile to be found in middle‐class‐dominant transport patterns and urban form in a number of North American cities. This paper further argues that in a developing country city such as Bangkok, where marked social differentiation and the combined population of poor and low‐income classes still comprise almost half of the urban social landscape despite an expanding middle‐class, an adequate and good public transport system that also meets the former’s need for efficient mobility is an imperative.  相似文献   

10.
A method based on logit analysis is suggested for predicting the effects on patronage and revenue of relative changes in peak and offpeak fares. The method also permits the ready estimation of consequent changes in service profitability. Data was collected specifically for this study from British Rail's Teesside corridor to achieve model calibration. Results show the extent to which demand in peak and offpeak fare‐periods is complementary when fare restrictions are applied only to the morning peak.  相似文献   

11.
Abstract

The institutional environment of rail transport has changed as a result of recent European directives, but the changes have taken different forms from one country to another. In the case of international maritime chains, the development of door‐to‐door services makes inland haulage from the loading and discharging ports extremely important, and it highlights the need to reshape the rail freight industry. This paper analyses the degree of involvement of different actors drawn from the maritime industry in developing and commercializing rail services in the changing regulatory environment. Several maritime operators, shipping lines, port‐handling companies and port authorities have been involved in some container rail services since the early days of liberalization. Their commitments take very different forms, however. Whereas contracts are mainly used for the provision of service, particularly for train haulage, integration by means of shareholding or creating subsidiaries or joint ventures is used for marketing. Important differences between France, the UK, Germany and the Netherlands are detailed. In the latter two countries, there is more involvement in the provision of rail services. Marketing rail services appear to be the main strategic issue for the maritime operators in all four countries  相似文献   

12.
Road‐based public transport in the cities of developing countries comes in a variety of physical and organizational forms. Many of these cities have a large component of unconventional or intermediate public transport (IPT). IPT often fills the gaps in service that cannot be provided by the operators of conventional public transport. The contrast in institutional framework between the operators of conventional vehicles and IPT is sharpened by the profitability of the two types; conventional buses, usually organized in large fleets and often run by the government, are seemingly difficult to maintain as a commercial enterprise whereas IPT which is usually privately owned in small fleets is profitable. A considerable debate has arisen over which type of public transport system (conventional or IPT) to encourage. The debate has often been confused because it involves two quite separate issues: whether the provision of public transport should be left entirely to private enterprise, and, the technical and economic benefits of different bus sizes. Size of vehicle is a particularly important issue in the developing world because vehicles of different size are in common use and are frequently in competition with one another. The purpose of this paper is to review and critically assess current research work on urban public transport with particular reference to vehicle size in the context of Third World conditions.  相似文献   

13.
Abstract

This paper reviews the main studies on transit users’ route choice in the context of transit assignment. The studies are categorized into three groups: static transit assignment, within‐day dynamic transit assignment, and emerging approaches. The motivations and behavioural assumptions of these approaches are re‐examined. The first group includes shortest‐path heuristics in all‐or‐nothing assignment, random utility maximization route‐choice models in stochastic assignment, and user equilibrium based assignment. The second group covers within‐day dynamics in transit users’ route choice, transit network formulations, and dynamic transit assignment. The third group introduces the emerging studies on behavioural complexities, day‐to‐day dynamics, and real‐time dynamics in transit users’ route choice. Future research directions are also discussed.  相似文献   

14.
15.
In Hong Kong the high cost of land reclamation servicing has made it necessary to plan land use through zoning commercial and industrial activity and by adopting very high densities for residential accommodation. Traffic has concentrated along particular corridors where its volume now exceeds road capacity. The imperative development of an urban rail system has affected the economic stability of most public transport. Simultaneously, private motoring has increased so rapidly that fiscal restraints have been imposed, generating a serious proposal for electronic road pricing. The future growth of links with China will end Hong Kong's relative isolation and present new transport planning challenges.  相似文献   

16.
PIET RIETVELD 《运输评论》2013,33(3):319-328
Supply‐oriented measures of quality lead to a systematic overestimate of quality as experienced by travellers in public transport. An example is a train with an average occupation rate for seats being 50%, where, nevertheless, the occupation rate observed by travellers is much higher when some parts of the trajectory are busy. Similar examples are discussed for waiting times at stops, probabilities of arriving in time, probabilities of getting a connection and walking distances to bus stops. A plea is then made for putting more effort in measuring demand‐oriented quality measures.  相似文献   

17.
Abstract

This paper explores the external costs of domestic container transportation in Taiwan by analysing the origin and destination of current container cargoes. After reviewing an extensive literature survey of methods of external cost, a comparison of external costs between trucking and short sea shipping (SSS) by corridor is made by using a model developed in this paper. Based on the findings that external costs of SSS are considerably lower than truck transport and can be a viable alternative to current domestic container cargo transportation, we discuss the significance and managerial implications of SSS from the perspective of green logistics. In so doing, a top‐down approach is employed for developing government policies, which aim to not only reduce the external costs of domestic container transportation but also promote SSS in Taiwan.  相似文献   

18.

Toronto is to have an urban transit system with a passenger carrying capacity which fills the gap between the capacity of the subway and the capacity of the car and bus. Correspondingly, in the words of the Premier of Ontario, the system will “make possible an attractive alternative to high‐rise, high‐density living and urban sprawl. . . .” Furthermore, the new system is sufficiently economical to provide “. . . an encouragement to growth in appropriate areas, rather than merely responding to growth as it occurs . . .”

The decision to have such a system is the culmination of some years of major transportation activities in the Province, which included the Metropolitan Toronto and Region Transportation Study (MTARTS) of 1962. This study pursued both urban expressways and public transport solutions to the movement of people in Metropolitan Toronto.

The urban expressways programmes ran into difficulties, on environmental terms, when strong opposition from community groups was met on proposed routes. A climax came when the Ontario Government halted the construction of the controversial Spadina expressway in June 1971. However, the programmes of public transport solutions met with great success. The Toronto subway and its extensions, together with the change in land values along the route, has become a classic success story. So, too, has the introduction of the GO Train Service (Government of Ontario train service). This pioneered a combination of commuter rail service and integrated feeder buses and today replaces some 14,000 cars each day along the lakeshore highways.

The success of the subway and the GO train coupled with the difficulties experienced by the urban expressways programme, gave rise to the realisation that a better city through public transport rather than the car, was practicable. However, subways were too expensive and they needed a large patronage in a narrow corridor. Accordingly, an intermediate capacity transit system was sought.

The paper describes the programme of activities involved in the choice of the system and describes the technical specification which the system will enjoy. In particular, the demonstration installation which is to be set‐up in Toronto is described in detail, together with the plans to instal some 56 miles over five routes in Metropolitan Toronto.  相似文献   

19.
Abstract

In an efficient transportation system, traffic safety is an important issue and it is influenced by many factors. In a country like Iran, until now safety improvements are mainly concentrated on road engineering activities, without much attention for vehicle technology or driving behaviour. One important aspect of road safety engineering activities is the so‐called treatment of hotspots or dangerous accident locations. Until recently, accident hotspots were identified and remedied by the esxperts’ personal judgements and a handful of statistics without taking into account other important factors such as geometric and traffic conditions of the road network. This paper therefore aims to define and identify the criteria for accident hotspots, then giving a value to each criterion in order to develop a model to prioritize accident hotspots when traffic accident data is not available. To do this, the ‘Delphi’ method has been adopted and a prioritization model is produced by the use of a ‘Multiple Criteria Decision‐Making’ method. The procedure is illustrated on a collection of 20 road sections in Iran. In addition, the model is validated against an existing database of road sections containing safe locations and hotspots. Finally, a sensitivity analysis is carried out on the proposed method.  相似文献   

20.
In the generally more dynamic modern business environment new modes of strategic planning have emerged, in which a premium is attached to the maintenance of flexibility in resource deployment. This paper discusses the principles involved, and considers the capacity of a segment of the sea ferry industry to exploit strategic flexibility as a means of coping with a rapidly changing environment. Potential sources of flexibility are examined in the paper and possible constraints identified. For the sector in question, it appears that strategic flexibility has been unduly limited by the nature of the resources employed, by prevailing corporate values, and by a tendency to respond to environmental uncertainty by short‐term reactions rather than long‐term measures. The general conclusion of the paper is that the sector examined, and possibly the industry as a whole, is strategically weak.  相似文献   

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