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1.
R. J. Allport 《运输评论》2013,33(4):365-384
This paper is concerned with the majority of developing nations who lack large resources for public sector projects. It questions the basis of much mass transit planning and attempts to put forward a more efficient way of reaching decisions. It calls extensively on experience of Metro Manila, capital of the Philippines, where an innovative system of metropolitan planning and administration is throwing a new light on ‘appropriate’ investment in such developing cities.

Mass transit systems as currently conceived in such developing cities—fully segregated rail‐based systems—are unlikely to be affordable (at least for many years) and in consequence scarce resources should not be devoted to developing and evaluating them. Rather, the principal objective should be to provide low‐cost, affordable mass transit—affordable to governments and to passengers. This almost certainly points to road‐based systems, or predominantly at‐grade light rail transit (LRT) systems, which are usually regarded as ‘obviously unworkable’ in developing city environments.

This judgement is questioned and it is suggested the potential of LRT to provide appropriate low‐cost mass transit is not being realized. An approach to determining its potential applicability is proposed. If feasible it should be evaluated against road‐based systems before decisions to implement new mass transit systems are taken.

While circumstances vary between countries the central message of this paper—that public sector resources have a very high opportunity cost which make all but the lowest‐cost mass transit systems very difficult to justify—will hold in all but the higher‐income developing economies.  相似文献   

2.
Using case study material, this paper examines the relative merit of metros and high performance bus systems in use in Third World cities. It demonstrates that buses with suitable priority measures are capable of meeting high passenger demands. The paper also shows that despite the poor financial performance and other shortcomings of metros, they can yield a respectable economic return. The paper draws on studies undertaken as part of the research program of the Overseas Unit of the Transport Research Laboratory.  相似文献   

3.
Abstract

In 2004, one of the biggest ferry operators in Norway was found guilty of having intentionally attempted to defraud the state of about 113 million Norwegian kroner in subsidies by underreporting revenues and overstating costs during the period 1992–2002. The company and five of the top managers were convicted and the case was regarded as one of the most serious subsidy offences ever committed in Norway. The aim of this article is to show that standardized revenue and cost norm models from the state can deter operators from committing such offences and when relevant detecting the fraud attempts at an early stage. Our model suggests that the operator in question overstated costs by about 19% and that the actual subsidy fraud attempt was about three times higher than concluded by the Court.  相似文献   

4.
A simplified simulation model for the operational analysis of a rail rapid transit train is presented. The model simulates the movement of a train along a route, and develops the relationships of time—distance, time—speed and distance—speed. The inputs to the model are the profile of speed limits and the dynamic characteristics of the train. Without the information on the track geometry and tractive effort, the model determines the speed of the train at a location based on the previous and future speed limits relative to the location. It was found that the model can fairly accurately simulate the relationship between travel time and distance. A comparison of the train travel times between the actual and simulated runs is presented. Because of the simplicity of input and calculation method, the model can be a useful tool for the “desk-top” analysis of frequently occurring planning problems of a commuter rail or rail rapid transit line, such as the impacts of changes in speed limits, station locations, station stopping policy, addition/elimination of stations, and types of rail cars.  相似文献   

5.
This paper describes current light rail transit planning and operation in Canada's major cities and smaller communities. There are ten urban areas in Canada with 250,000 or more people. Two of these have light rail systems in operation, three have lines under construction and nine others are planning LRT systems.  相似文献   

6.
Operating speed of a transit corridor is a key characteristic and has many consequences on its performance. It is generally accepted that an increased operating speed for a given fleet leads to reduced operating costs (per kilometer), travel and waiting times (three changes that can be computed precisely), an improved comfort and level of service, which can attract new passengers who are diverted from automobile (items harder to estimate precisely). That is why several operation schemes which aim to increase the operating speed are studied in the literature, such as deadheading, express services, and stop skipping.A novel category of solutions to this problem for one-way single-track rail transit is to perform accelerated transit operations with fixed stopping schedules. The concept is quite simple: as the time required for stopping at each station is an important part of travel time, reducing it would be a great achievement. Particular operations that take advantage of this idea already exist. This paper focuses on one of them: the skip-stop operation for rail transit lines using a single one-way track. It consists in defining three types of stations: AB stations where all the trains stop, and A and B stations where only half of the trains stop (stations type A and B are allocated interchangeably). This mode of operation is already described in the literature (Vuchic, 1973, Vuchic, 1976, Vuchic, 2005) and has been successfully implemented in the Metro system of Santiago, Chile.This work tackles the problem with a continuous approximation approach. The problem is described with a set of geographically dependent continuous parameters like the density of stations for a given line. Cost functions are built for a traditional (all-stop) operation and for skip-stop operation as described above. A simple example is presented to support this discussion. Finally, a discussion about the type of scenarios in which skip-stop operations are more beneficial is presented.  相似文献   

7.
New light rail service usually calls for routing feeder buses at the outer rail stations. This implies early service planning for revisions to an existing bus network—Part I analyzes bus or trolley revisions in Northeast Edmonton, by comparing the before and after conditions. It briefly reviews bus reroutings in South Calgary and how they differ from Edmonton. A new light rail line also warrants physical planning at rail stations chosen for modal interface. Levels of feeder service partly determine scale and layout of the stations' fixed facilities. Part II mostly describes elements integrated with rail station platforms in South Calgary. It also presents new station area plans at the end of Northeast Edmonton line. Part (III) compares park'n ride lot options preferred by Edmonton and Calgary, or so far studied in Vancouver. It analyzes access mode split for Edmonton and Calgary outer stations.  相似文献   

8.
Extensive work exists on regular rail network planning. However, few studies exist on the planning and design of ring-radial rail transit systems. With more ring transit lines being planned and built in Asia, Europe and the America's, a detailed study on ring transit lines is timely. An analytical model to find the optimal number of radial lines in a city for any demand distribution is first introduced. Secondly, passenger route choice for different rail networks is analyzed, for a many-to-many Origin-Destination (OD) demand distribution, based on a total travel time cost per passenger basis. The routes considered are: (1) radial lines only; (2) ring line only or radial lines and ring line combined; or (3) direct access to a destination without using the rail system. Mathematica and Matlab are used to code the route choice model. A cost-benefit optimization model to identify the feasibility and optimality of a ring line is proposed. Unlike simulations and agent-based models, this model is shown to be easily transferable to many ring-radial transit networks. The City of Calgary is used as an example to illustrate the applicability of each model. The existing urban rail network and trip distribution are major influencing factors in judging the feasibility and optimal location of the ring line. This study shows the potential net benefit of introducing a ring line by assessing changes in passengers’ costs. The changes in passenger cost parameters, such as ride cost and access cost, are shown to greatly influence the feasibility of a ring line.  相似文献   

9.
Using data from North American rail transit properties, short and long run cost functions are estimated using a neoclassical economic model. Various special econometric techniques are employed to estimate the relationships from a heterogeneous data set. The estimated cost functions are then used to forecast the cost experience of the BART system in San Francisco.  相似文献   

10.
This study develops a model that explains public transit ridership in Orange Country, California over quarterly periods during the 1974–1988 period. The model uses a Cobb-Douglas functional form and a Cochrane-Orcutt iterative procedure to measure the association between public transit ridership and the potential number of users, relative level of public transit service, relative price of public transit, seasonality, and external shocks. Relative measures of the explanatory variables are used to reduce the potential for multicollinearity and give greater confidence in the reliability of the estimated elasticities. The model is then used to prepare conditional quarterly forecasts for ridership in 1988 and unconditional quarterly forecasts during the 1989–1993 period.  相似文献   

11.
The paper presents a procedure that has been developed for estimating subsidization requirements for urban transit services in developing countries. The procedure is based on a subsidization policy of reducing transport expenditure burden on the average commuter, by maintaining his transport expenditure-income ratio at a reasonable level. It is designed for both regulated and deregulated transport markets. It requires, as input, historical data (previous year) on fare, productivity, and load factor for the transport service or mode concerned, the transport expenditure-income ratio distribution of the commuters, and the current level of commuter personal transport allowance. It is based on the premise that transport expenditure-income ratio is inversely related to income. The subsidization formula developed in the paper yields a level of subsidy that is commensurate with the level of control a government is able to exercise over transit operations.  相似文献   

12.
In recent years interest in light rail transit has grown substantially in the United States. The concept of LRT is increasingly viewed as a possible answer to the search for a less costly rail transit technology that could reduce America's dependency on the private automobile and put the country on the road to a more secure, self-sufficient energy future. The paper reviews recent LRT developments in four American cities, two of which have undertaken to rehabilitate and upgrade their existing surface street railway systems, and the other two have embarked upon construction of entirely new light rail systems.  相似文献   

13.
This paper provides a hierarchical customer satisfaction framework to measure rail transit lines’ performances in Istanbul. The problems related to rail transit line systems are addressed via customer satisfaction surveys. Then, a framework is proposed combining statistical analysis, fuzzy analytic hierarchy process, trapezoidal fuzzy sets and Choquet integral to evaluate customer satisfaction levels. Next, the criteria need to be improved are determined and specific recommendations to enhance the operation for specific lines are suggested. The proposed framework provides directions for the future investments and it also can be used at a more macroscopic level to determine the operational deficiencies. Furthermore, it can be generalized and applied to complex decision making problems that include uncertain and subjective data or vague information.  相似文献   

14.
The deficiencies in the Istanbul transportation system have led the local authorities to plan several alternative transportation projects. In this paper three alternative rail transit network proposals are evaluated by using Analytic Hierarchy Process (AHP), a multiple criteria decision support system. The AHP facilitates decision-making by organizing perceptions, experiences, knowledge and judgments, the forces that influence the decision, into a hierarchical framework with a goal, scenarios, criteria and alternatives of choice. Based on this analysis, the decision makers have developed a new alternative as a combination of the most closely competing two alternative rail transit networks. This combination rail transit network is currently under construction.  相似文献   

15.
徐家汇地区是上海市的城市副中心,人流量大,商业繁华,交通繁忙,地下管线纵横交错.地铁R1、R3、R4三条线在此中心交汇,形成大型换乘枢纽.文章简单地介绍了大型换乘枢纽的线路和建筑方案,并对施工和交通组织方案进行了深入研究.  相似文献   

16.
This paper considers the train scheduling problem for an urban rail transit network. We propose an event-driven model that involves three types of events, i.e., departure events, arrival events, and passenger arrival rates change events. The routing of the arriving passengers at transfer stations is also included in the train scheduling model. Moreover, the passenger transfer behavior (i.e., walking times and transfer times of passengers) is also taken into account in the model formulation. The resulting optimization problem is a real-valued nonlinear nonconvex problem. Nonlinear programming approaches (e.g., sequential quadratic programming) and evolutionary algorithms (e.g., genetic algorithms) can be used to solve this train scheduling problem. The effectiveness of the event-driven model is evaluated through a case study.  相似文献   

17.
目前,北京市在同时建设多条轨道交通线路,建设规模大、工期紧、工法多、周围环境复杂,工程难度大.为了配合新线建设,推进科技创新,提高新线工程建设的施工质量、技术水平和科技含量,一些技术难点问题需要进行研究攻关.文章重点就北京地铁4号、5号、10号线正在研究和有待研究的一些课题的必要性和关键技术问题进行阐述并提出建议,可供参考.  相似文献   

18.
A number of forces currently at work in the United States are fostering the rebirth of urban rail transportation. In order to maximize the beneficial economic and developmental impact of future rail investment, certain procedures and techniques must be employed in the planning, design, and implementation of rail systems. The paper offers a set of guidelines and principles for transportation and land use policy makers.  相似文献   

19.
Crime and fear of crime is a major problem plaguing U.S. transit systems, particularly those serving large urban areas. This paper presents a normative framework for assessing rail transit security following a system-wide metric approach. The security metric can also be used to assess the marginal improvement in security as a result of improving or adopting alternative policing and monitoring strategies. The model consists of five tasks: surveying rail transit security systems, developing a rail transit security metric, assigning efficiency ratings to rail security functions, developing a composite index for the efficiency of the overall security system, and applying a probability matrix to temper the results. Efficiency ratings can be translated into probability of occurrence figures that can be used in a decision tree context to improve rail transit security.  相似文献   

20.
This paper presents two time series regression models, one in linear form and the other in logarithmic form, to estimate the monthly ridership of a single urban rail rapid transit line. The model was calibrated for a time period of about six and a half years (from 1978–1984) based on ridership data provided by a transit authority, gasoline prices provided by a state energy department, and other data.The major findings from these models are: (1) seasonal variations of ridership are –6.26%, or –6.20% for the summer period, and 4.77%, or 4.62% for the October period; (2) ridership loss due to a station closure is 2.46% or 2.41%; and (3) elasticities of monthly ridership are –0.233 or –0.245 with respect to real fare, 0.113 or 0.112 with respect to real gasoline price, and 0.167 or 0.185 with respect to real bridge tolls for the competing automobile trips. Such route specific application results of this inexpensive approach provide significant implications for policymaking of individual programs in pricing, train operation, budgeting, system changes, etc., as they are in the case reported herein and would be in many other cities.  相似文献   

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