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1.
ABSTRACT

As maintenance and operation costs increase with usage over time, equipment is replaced when the value of new equipment is more attractive. Some methods have been developed to solve this problem. In the public transport sector, such problems are frequently analyzed by fleet managers and determined by bus age restriction regulations. We propose an Integer Programming model that integrates both budgetary and environmental constraints (CO2 emissions) which, as far as we know, have not previously been studied in conjunction. The study aims to determine the optimal replacement plan for a fleet of diesel buses of different size, age, maintenance costs and emissions rates, with new (less polluting) diesel buses over a time horizon of 50 years. The results indicate that it is possible to reduce emissions with a low annual budget using an optimal replacement policy.  相似文献   

2.
Abstract

This paper puts forward a methodology for designing a system for school transport which, apart from designing routes, specifies school opening times. Traditionally school opening times have always been identical in the same area meaning many buses have to be used at the same time. This paper suggests the staggering of school opening times in order to minimise the number of buses and thereby reduce the enormous costs involved in running them. The methodology is based on: a first phase which addresses the classic routing problem by using mixed integer lineal programming and a second phase which uses bi-level programming to find the vector for school opening times, which, when staying within the constraints of the problem, minimises the direct costs of the system. The upper level represents the evaluation of the system costs and the lower level finds the best combination of optimum routes for the same bus.  相似文献   

3.

A methodology for comparing phased implementation plans for a new fixed guideway transit system in an urban area is presented. Four assumptions are made: (1) the guideway system replaces existing or planned bus service, (2) superior service on the new system results in increased ridership when compared to buses; (3) presence of the guideway facility redirects outward urban growth resulting in additional ridership, and (4) conversely, the absence of any action on the new guideway facility reinforces a diffuse urban growth pattern that creates an irreversible loss of transit ridership. The economic comparision of alternative plans includes total as well as “relative” inflation of principal cost components. A key feature of the proposed methodology is including in the comparisons the costs of private automobile mileage that could have been replaced by transit. These costs are expressed as “fuel” and “all other” automobile costs; favorable transit system implementation schedules can then be identified as a function of parametrically assumed values for these two unit costs. A hypothetical example demonstrates the proposed method.  相似文献   

4.
David Metz 《运输评论》2013,33(4):375-386

Mobility declines with increasing age, reflecting the onset of physical or mental infirmity, affordability of travel for those on retirement incomes, and the mal-design of the transport infrastructure and operational arrangements. With the prospect of a rapidly ageing population, it is important to address measures to promote mobility if the quality of life of older people is to be sustained. In the UK, pensioners on low incomes, who could be hindered in their travel by the cost of fares on public transport, benefit from the general availability of half price (or better) concessionary fares for local travel. A variety of measures are in place to counter the effects of age-associated disabilities that hinder mobility, including low floor buses, subsidised taxis and community transport schemes. The Disability Discrimination Act is ensuring that public services vehicles are accessible to older people with disabilities. The motor car is of increasing importance in later life, particularly for those with disabilities, and a variety of design and technological approaches are being brought to bear to maintain the mobility of older people. These various efforts undoubtedly enhance the mobility of older people. However, beyond that broad conclusion it is hard to make evidencebased judgements. There is therefore a pressing need to develop methods to evaluate developments in policy and practice.  相似文献   

5.
Abstract

The number of bus‐based Park and Ride (P&R) schemes in the UK has grown substantially over the past 40 years as a result of its encouragement by the Government as a tool to deal with increasing traffic congestion and traffic‐related pollution. The aim of this article is to analyse the degree to which P&R is effective in the contemporary policy context. The authors identify phases of development of P&R since its emergence as a local solution to transport capacity constraints in historic towns. Policy goals are identified against which a review of literature is used to highlight its effectiveness. It is concluded that P&R may increase the distance travelled by its users due to low load factors on dedicated buses, public transport abstraction and trip generation, although it is highlighted that there are areas in which further research is required to clarify its impacts.  相似文献   

6.

The Sydney Olympics held in September 2000 provided an opportunity to monitor the planning of transport provision for the world's greatest sporting spectacular. As the single largest major event, the pressures on a city's transport system are enormous, as witnessed by the previous Games in Atlanta and Barcelona. This paper takes a value-chain approach to assess transport performance as a crucial element in the delivery of the Sydney Olympic Games. We begin with a brief overview of strategic value, highlighting some generic aspects of value chains followed by the transport delivery system that came to the fore as significant 'drivers' in the value chain. This is followed by a summary of the effectiveness of the buses, trains, taxis, roads and the airport. A more detailed look is provided of the private bus sector where the problems leading up the opening of the Games received a great deal of media attention. The paper concludes with two stories, one good, one not so good, about transport and the Olympic Games.  相似文献   

7.
The paper is devoted to Warsaw, a city burnt to the ground during World War II and reconstructed from its ruins. This allowed the post‐war designers to change the road network and modernize the system of transport. This modernization, however, has turned out not to be far‐sighted enough: hence the present transport difficulties.

Compared with Western European cities car traffic is less intensive and smoother. The high density of places of work in the central district and of inhabitants in residential districts has resulted in a shortage of parking places. Most people use public transport comprising buses, trams and railways; trolley buses and taxis are less used. Buses are the most frequently used transport within the city; railways play a similar role in the city‐suburban zone connections. The first underground line is under construction.

The immense amount of daily travel is generated mainly by the inappropriate distribution of residences, places of work and services, and secondly by the low fares on public transport, which is subsidized by the state and works more as a social service than as a branch of the economy.  相似文献   

8.
E. S. W. Lee 《运输评论》2013,33(4):279-303

As paratransit services, Hong Kong's taxis and public light buses (PLB) carried some 30% of the 9.7 million daily public transport boardings in Hong Kong in 1988. Most of the vehicles are individually owned, and services are operated as commercially viable concerns. While operators have a high degree of operational flexibility, taxis and PLBs are closely regulated by the Government. The fleet sizes are controlled by licensing. There is a system of zoning for taxis, and operational prohibitions and restrictions for PLBs. Over the years, Hong Kong has developed some practicable means of operational control on taxis and PLBs. It has been 20 years since PLBs were legalized in 1969. The transition experienced by this mode, from no control to regulated operations, signifies a major step forward from the point of view of transport administration. The Government's participation in the planning for PLB services has guided the development of this mode. In this paper, the planning and control mechanisms for Hong Kong's paratransit modes are introduced. Identified deficiencies are also discussed.  相似文献   

9.

This paper tries to construct a performance evaluation procedure for highway buses with the financial ratio taken into consideration. First, a conceptual framework is redeveloped, based on the one created by Fielding et al ., to help form evaluation items and performance indicators involving both transport and finance aspects. Second, the total performance is divided into three major kinds of efficiency?production, marketing, execution?according to the cycle of operation activities. Third, to overcome the problems of small sample size and unknown distribution of samples, the grey relation analysis is used to select the representative indicators, and the TOPSIS method is used for the outranking of highway bus. In addition, a case study is conducted using four highway bus companies as example. The empirical result shows that the performance evaluation for highway buses could become more comprehensive if financial ratios are considered.  相似文献   

10.
ABSTRACT

A transport initiative, like any kind of public action, has an impact on the monetary cost, time cost, efficiency and comfort of the transportation of goods and people, in particular transport infrastructure investments. All such initiatives are subject to cost benefit analyses at the national and EU level to know whether the present value of total net benefits including environmental impacts exceeds their cost. However, several important policy issues remain unresolved in standard evaluation procedures. One issue is whether the so-called direct measurement of user benefit, which consists of quantifying changes in surplus of the users of the transport system, captures all welfare generated in the economy. Another issue is how the gains (or possibly losses) of a transport initiative are distributed among regions. The aim of this article is to perform a systematic and quantitative analysis of the socio-economic and spatial impacts of alternative transport investments by carrying out scenario simulations in order to improve the understanding of the impact of transportation policies on the short- and long-term spatial development in Latvia. The general result from the scenario simulations is that rail projects seem to be more effective in terms of promoting regional economic activity than road projects.  相似文献   

11.
For the UK to meet their national target of net zero emissions as part of the central Paris Agreement target, further emphasis needs to be placed on decarbonizing public transport and moving away from personal transport (conventionally fuelled vehicles (CFVs) and electric vehicles (EVs)). Electric buses (EBs) and hydrogen buses (HBs) have the potential to fulfil requirements if powered from low carbon renewable energy sources.A comparison of carbon dioxide (CO2) emissions produced from conventionally fuelled buses (CFB), EBs and HBs between 2017 and 2050 under four National Grid electricity scenarios was conducted. In addition, emissions per person at different vehicle capacity levels (100%, 75%, 50% and 25%) were projected for CFBs, HBs, EBs and personal transport assuming a maximum of 80 passengers per bus and four per personal vehicle.Results indicated that CFVs produced 30 gCO2 km−1 per person compared to 16.3 gCO2 km−1 per person by CFBs by 2050. At 100% capacity, under the two-degree scenario, CFB emissions were 36 times higher than EBs, 9 times higher than HBs and 12 times higher than EVs in 2050. Cumulative emissions under all electricity scenarios remained lower for EBs and HBs.Policy makers need to focus on encouraging a modal shift from personal transport towards sustainable public transport, primarily EBs as the lowest level emitting vehicle type. Simple electrification of personal vehicles will not meet the required targets. Simultaneously, CFBs need to be replaced with EBs and HBs if the UK is going to meet emission targets.  相似文献   

12.
ABSTRACT

This paper describes the development of a probabilistic formulation that provides global optimum selection and allocation of a fleet of buses in a private transportation system of an organization where a third party is hired to provide transportation for its employees and their dependents. In this private transportation system, a fleet of buses is to be selected and allocated to serve employees and their independents on different prescheduled trips along different routes from the organization’s headquarters and residential compound where round-trip times of scheduled trips are subject to uncertainty due to random delays. We propose a probabilistic approach based on 0-1 integer programming for the selection and allocation to determine the optimal number and size of buses assigned to a set of prescheduled trips in a particular time interval. Examples and a case study are presented to illustrate the applicability and suitability of the proposed approach.  相似文献   

13.
Alan Gilbert 《运输评论》2013,33(4):439-467
Abstract

Successful mass transit solutions are rare in poor cities. When they appear they are lauded across the globe and too often copied uncritically. The latest exemplar of such best practice is the ‘Transmilenio’ rapid bus system in Bogotá. The article describes its main characteristics and applauds the improvements that it has already brought to urban transport in Bogotá. Naturally, the system is not without its flaws and these need to be drawn to the attention of those who might copy the Bogotá example. This is particularly important at the present time when the jewel of Bogotá has come under surprisingly strong local criticism over its cost, its ownership structure, its decreasing effectiveness and, fundamentally, because it has failed to solve the transport chaos of Bogotá. There is a real danger that ‘Transmilenio’ will stagnate as its popularity declines and as demands for a metro increase. Given the strengths of the system that would be something of a disaster and, most certainly, not in the interests of the poor.  相似文献   

14.

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   

15.

Despite the hundreds of billions of dollars being spent on infrastructure development -- from roads, rail and airports to energy extraction and power networks to the Internet -- surprisingly little reliable knowledge exists about the performance of these investments in terms of actual costs, benefits and risks. This paper presents results from the first statistically significant study of cost performance in transport infrastructure projects. The sample used is the largest of its kind, covering 258 projects in 20 nations worth approximately US$90 billion (constant 1995 prices). The paper shows with overwhelming statistical significance that in terms of costs transport infrastructure projects do not perform as promised. The conclusion is tested for different project types, different geographical regions and different historical periods. Substantial cost escalation is the rule rather than the exception. For rail, average cost escalation is 45% (SD=38), for fixed links (tunnels and bridges) it is 34% (62) and for roads 20% (30). Cost escalation appears a global phenomenon, existing across 20 nations on five continents. Cost estimates have not improved and cost escalation not decreased over the past 70 years. Cost estimates used in decision-making for transport infrastructure development are highly, systematically and significantly misleading. Large cost escalations combined with large standard deviations translate into large financial risks. However, such risks are typically ignored or underplayed in decision-making, to the detriment of social and economic welfare.  相似文献   

16.

This paper summarizes the constraints which a technological innovation in transport must satisfy if it is to achieve widespread application. The existing and likely future travel demands in Australia are reviewed, and for certain types of travel it is concluded that existing modes may become unsuitable or unacceptable. In these areas, it is possible that a new transport technology may find application. In all other areas, it is considered that existing modes, or their functional successors, will continue.

Five possible demand areas in which new transport technology may find application are identified. These are as follows:

1) High speed distribution systems may be introduced in Australian CBD's (Central Business Districts) within the next ten years. These may be progressively extended to provide radial public transport services to the CBD. It is also possible that these systems may eventually be extended to provide a dual‐mode capability in inner‐suburban areas as a partial alternative to freeway construction.

2) New town developments which may be introduced in Australia could include various forms of advanced transportation systems.

3) New aviation modes, possibly including short take off and landing aircraft operating from suburban airports may be introduced to cater for inter‐urban travel.

4) A demand‐responsive transport system to cater for the needs of the transport poor in urban areas may find limited application.

5) In the longer term, possibly by the turn of the century, an improved transport system capable of providing door‐to‐door service over the whole of an urban area and operating under a dual‐mode configuration appears to be possible. It probably would emerge from development of an incremental nature and eventually include the installation of a new technology in the then existing freeway and railway reservations in the city.  相似文献   

17.
Abstract

A phenomenon new to the Polish situation—the deregulation of rail transport—is presented. Despite its primarily legal nature, deregulation also implies various economic, socio‐political and spatial consequences. The relatively short period over which partial deregulation of public transport in Poland has been in effect (i.e. since 2000) ensures that the issue has not been taken up by Polish geographers as a research field. However, it has been of interest to Polish economists. Deregulation is a phenomenon of primary importance, with direct implications for the character, quality, type, intensity and spatial differentiation of transport (including freight and passenger traffic) within the market economy. This paper, therefore, presents the impact of the recent changes in the legal system (as regards deregulation) on the current pattern of railway connections of the major carriers. As the majority of these originate beyond the Polskie Koleje Państwowe (Polish State Railways) Group, they can be said to be independent of the main former state carrier.  相似文献   

18.
BackgroundPublic transport is low cost, allows for independence, and facilitates engagement and participation for non-drivers. However, the viewpoints of individuals with cognitive disabilities are rarely considered. In Australia, the prevalence of Autism Spectrum Disorders (ASD) is approximately 1% and increasing. Many individuals with ASD do not possess a driver’s licence, indicating that access to public transport is crucial for their independence. However, at present, there is no research on the opinions of adults with ASD on public transport.AimTo identify the viewpoints of adults with ASD regarding the barriers and facilitators of public transport usage and their transportation preferences, and to contrast these against the viewpoints of neurotypical adults.MethodsQ method was used to identify the viewpoints of both participant groups on public transport. Participants consisted of 55 adults with a diagnosis of ASD and a contrast group of 57 neurotypical adults. Both groups completed a Q sort task which took place in either Perth or Melbourne, Australia.ResultsThe most prominent viewpoint indicated that both groups preferred to use public transport over driving and believed that it supported their independence. This viewpoint also indicated that both groups preferred to use electronic ticketing when using public transport. Interestingly, the second most prominent viewpoint indicated that both groups preferred to drive themselves by private car rather than use public transport.DiscussionIt appears that the viewpoints of adults with and without ASD regarding public transportation were largely similar. However, questions arose about whether the preference for public transport in the ASD group may be more a result of difficulties obtaining a driving licence than a deliberate choice. The only barrier specified by adults with ASD related to crowding on public transport. Safety and convenience in relation to location and timing of services were barriers reported by neurotypical adults.  相似文献   

19.
This paper shows the results of a comparative fleet test the main objective of which was to measure the influence of Low Viscosity Oils (LVO) over the fuel consumption and CO2 emissions of urban buses. To perform this test, 39 urban buses, classified into candidate and reference groups depending on the engine oil viscosity, covered a 60,000 km mileage corresponding to two rounds of standard Oil Drain Interval (ODI). In the same way, for 9 buses of the 39 buses, the effect of differential LVO over fuel consumption and their interaction with engine LVO was assessed during the second ODI.Test results confirm that the use of LVO could reduce fuel consumption, hence CO2 emissions. However, special attention should be taken prior to its implementation in a fleet, particularly if the vehicles are powered by engines with high mechanical and thermal stresses during vehicle operation because this could lead to friction loss increase, loss of the potential fuel consumption reduction of LVO and, in the worst scenario, higher rates of engine wear.  相似文献   

20.
Abstract

There is a growing tendency in cities around the world to invest in Bus Rapid Transit (BRT) systems in an attempt to improve the capacity and quality of public transport services. The appeal of BRTs is based on their ability to combine the service level of rail transit systems with the flexibility of buses at relatively lower investment costs, and this was the motivation behind the opening of such a system in the Turkish city of Istanbul in 2007. This system has attracted mixed opinions as to its performance, as while passenger ridership figures are extremely high, proving the effectiveness of the system, there is an argument that the corridor should have been developed with rail technology, and that the BRT is failing to meet the demand. The paper presents a comprehensive analysis of this system, assessing its planning and performance through a comparative analysis of a number of BRTs in the world and Istanbul's metro and tram systems. The analysis confirms the success of the system in terms of passenger statistics, but also highlights a number of problems in certain planning decisions that should be addressed, thus taking the discussion beyond a simplified comparison of bus and rail technologies.  相似文献   

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