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1.
This research examines the problem of route bus specification and vehicle manufacturability. In order for bus operators to provide transport services, a range of vehicle configurations must be available from bus manufacturers, generating variety which has a negative impact on the manufacturing process. Larger part inventories, uncontrolled labour tasks and more troublesome maintenance are known impacts of this variety. This research identifies the functional necessities in route bus interior design and reduces the problems in bus manufacture and operation caused by specification diversity by proposing a modularised system of bus design. In particular, it makes recommendations as to how bus configuration should be carried out, ensuring an optimum mix of operational and manufacturing needs:
  • 1.Determine user needs before the bus specification process.
  • 2.Designs to be developed by the manufacturer in response to user needs.
  • 3.This design should be standardised where possible, as suggested by the user needs.
  • 4.Where user needs dictate product variations, apply a mass customisation approach to accommodate these needs.
The recommendations are communicated in design proposals for a modular bus interior, demonstrated by four cases designed to meet the present status quo of bus interior design and predictions for the future of the field.  相似文献   

2.
To ensure that the advanced emission control systems installed on modern motor vehicles continue to work properly, motor vehicle inspection and maintenance (I/M) programs are now found in the major cities of many countries around the world. These programs are widely regarded as valuable and even essential to the achievement of air quality objectives, but there have been few ex post audits of these programs. In this paper, we examine the performance of one of the most sophisticated I/M programs, the USEPA’s Enhanced I/M Program. This program has now been implemented in five states. Using data from 1995 and 1996, we estimate the cost of the Arizona Enhanced I/M Program and the emission reductions achieved. We begin by enumerating briefly the components of I/M costs and discuss their size and incidence. Then we describe the empirical information from Arizona and how we use it to construct cost estimates for both vehicle inspection and repair of failing vehicles. Inspection costs include the costs of operating the test stations and the costs motorists incur in time and money to get to the station and go through the testing process. We find that the inspection costs account for over two-thirds of the full costs of I/M, while costs associated with actual vehicle repair account for only one-third. We conclude by comparing the empirical estimates of costs and program effectiveness in the Arizona program with the ex ante estimated Enhanced I/M program costs made by the EPA in the 1992 Regulatory Impact Analysis (RIA). The ex ante EPA analysis appears to have underestimated the costs of achieving the ambitious reductions in emissions hoped for under I/M.  相似文献   

3.
Although inevitably there are grey areas, a distinction may be drawn between environmental disbenefits arising from vehicles which cause annoyance, such as noise, or loss of peace and quiet, vibration, visual intrusion, severance, and those which endanger life and limb. Legislation implemented to reduce either category will inevitably generate costs.It is suggested that in evaluating legislation relating to environmental nuisance, attempts should be made carefully to measure the benefits, while for legislation when life and limb is involved a cost-effectiveness approach should be adopted. Methods currently available to measure environmental nuisance arising from vehicles, for example opinion surveys, observing the effect of changes in some independent indicator, and simulation exercises are critically examined. Using evidence from the Urban Motorway Committee Reports, Noise Advisory Council, Transport and Road Research Laboratory surveys on the effect of traffic in selected High Streets, and the Realistic Environment Assessment Laboratory, Social and Community Planning Research ping-pong technique, studies of house price differentials, and estimates of willingness-to-pay for exclusion facilities, an attempt is made to highlight the dilemma that while benefits of environmental nuisance legislation should be carefully weighed against the anti-pollution costs, techniques currently available for measuring such benefits are very underdeveloped.Paradoxically there is a far more clear-cut procedure for valuing benefits of policies affecting life and limb. Official accident evaluation policy in the U.K. is described, and legislation affecting life and limb is examined.Finally, difficulties of effectively enforcing legislation of both environmental nuisance and life and limb categories are illustrated.  相似文献   

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6.
The effects of fuel price on travel demand for different income groups reveal the choices and constraints they are faced with. The first purpose of this study is to understand these underlying choices and constraints by examining the variation of fuel price elasticity of vehicle miles travelled (VMT) across income groups. On the other hand, the rebound effect—increase in VMT as a result of improvement in fuel efficiency may offset the negative effect of fuel price on VMT. The second purpose of this study is to compare the relative magnitudes of the fuel price elasticity of VMT and the rebound effect. A system of structural equations with VMT and fuel efficiency (MPG, miles per gallon) as endogenous variables is estimated for households at different income levels from 2009 National Household Travel Survey. Higher income households show greater fuel price elasticity than lower income households. Fuel price elasticities are found to be ?0.41 and ?0.35 for the two highest income groups, while an elasticity of ?0.24 for the lowest income group is identified. The rebound effect is found to be only significant for the lowest income households as 0.7. These findings suggest the potential ability of using fuel price as a tool to affect VMT. The study results also suggest possible negative consequences faced by lower income households given an increase in fuel price and call for more studies in this area.  相似文献   

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This paper examines the relative importance that people attach to various instrumental and affective journey attributes when travelling either for work or for a leisure day trip and presents how journeys by various travel modes score on these attributes. Although not a comparative paper, data are presented for two studies which used some identical measurements: one on commuter journeys and one on leisure journeys. The results show that for work journeys, respondents tend to attach more importance to instrumental aspects, and especially to convenience than to affective factors. For leisure journeys, however, respondents appear to attach almost equal importance to instrumental and affective aspects, particularly flexibility, convenience, relaxation, a sense of freedom and ‘no stress’. Each study also examines (i) how regular users’ evaluate their own mode and (ii) how car users perceive the performance of alternative modes compared to their importance ratings. This ‘gap’ analysis reveals on which modes and for which attributes the greatest deficiencies in performance lie. The data for both the work and leisure studies shows that for car users, alternative transport modes are inferior on the salient attributes such as convenience and flexibility even though car users rate modes such as walking and cycling as performing well, if not better, on less important attributes such as the environment, health and even excitement. Nevertheless, for those who cycle and walk regularly, satisfaction with their own travel mode as measured by the gap between importance and performance on salient attributes is better than for those who mostly use the car. Conclusions are made as to how greater attention to affective factors may improve our understanding of mode choice.  相似文献   

9.
Intelligent Transportation System (ITS) can play an important role in reducing risks and increasing traffic safety. Discussion as to whether a technological approach or a behavioral approach is the right way to achieve a safer traffic environment forms a point of departure for this paper. On the one hand, there are the technicians who emphasize technology as the way towards safer traffic. Behaviorists, on the other hand, view the drivers’ behavior as fundamental and argue that education and incentive-oriented policies are essential in order to influence the driver and therefore increase traffic safety. Independent of the approach advocated a successful outcome of either a technological improvement, or an information campaign, has to be based on a high level of acceptance among potential users. In order to increase traffic safety, it is therefore essential to recognize driver motivation and attitudes. In this paper we focus on drivers’ attitudes towards risk, traffic safety and safety measures. A study of drivers’ attitudes and acceptance of an electronic device for speed checking (which the drivers tested for nine months) indicated a high acceptance level. The drivers perceived that they had both become more aware of traffic regulations and behaved in accordance with safety regulations.  相似文献   

10.
This paper reviews trends in cycling levels, safety, and policies in Canada and the USA over the past two decades. We analyze aggregate data for the two countries as well as city-specific case study data for nine large cities (Chicago, Minneapolis, Montréal, New York, Portland, San Francisco, Toronto, Vancouver, and Washington). Cycling levels have increased in both the USA and Canada, while cyclist fatalities have fallen. There is much spatial variation and socioeconomic inequality in cycling rates. The bike share of work commuters is more than twice as high in Canada as in the USA, and is higher in the western parts of both countries. Cycling is concentrated in central cities, especially near universities and in gentrified neighborhoods near the city center. Almost all the growth in cycling in the USA has been among men between 25-64 years old, while cycling rates have remained steady among women and fallen sharply for children. Cycling rates have risen much faster in the nine case study cities than in their countries as a whole, at least doubling in all the cities since 1990. They have implemented a wide range of infrastructure and programs to promote cycling and increase cycling safety: expanded and improved bike lanes and paths, traffic calming, parking, bike-transit integration, bike sharing, training programs, and promotional events. We describe the specific accomplishments of the nine case study cities, focusing on each city’s innovations and lessons for other cities trying to increase cycling. Portland’s comprehensive package of cycling policies has succeeded in raising cycling levels 6-fold and provides an example that other North American cities can follow.  相似文献   

11.
Currently, two immersed tunnels are being constructed in Holland as part of a high speed railway link. Designing and building these two tunnels was a challenge due to a combination of factors: Technical specifications with small tolerances, which are never encountered before in Holland, poor soil conditions and a short construction period had to be managed.Some major aspects will be explained in this paper.  相似文献   

12.
This paper analyzes the transportation and land-use preference and actual neighborhood choices of a sample of 1,455 residents of metro Atlanta. We develop a stated-preference scale on which desires for neighborhood type are gauged, from preferences for low-density, auto-oriented environments to desires for compact, walkable, and transit-oriented neighborhoods. This scale is then related to desires for change in one’s own neighborhood characteristics after a hypothetical move. If all neighborhood preferences were equally likely to be satisfied, then neighborhood preferences would not be correlated with a desire for change. By contrast, in the current study, stronger preferences for a more walkable environment are associated with greater desire for change in one’s neighborhood characteristics. This suggests an undersupply of compact, walkable, and transit-friendly neighborhood types relative to current demand.
Lawrence D. Frank (Corresponding author)Email:
  相似文献   

13.
The cost of using private finance is at the centre of the public private partnerships (PPPs) debate, but until now most works considered only the direct financial costs such as the loan interest rate and the shareholders return on equity and were based on various secondary sources. This paper focuses on seven shadow toll deals closed in Portugal between 1999 and 2002 and reports the financial costs of the PPP model considering also the associated transaction costs and is based on detailed information included in each concession's financial base case. The transaction costs include financial costs such as banking fees, due diligence costs and the impact of all cash distribution traps, such as reserve accounts or minimum-level of debt ratios. The PPP financial costs were then compared with the costs arising from raising public debt through a government or a public agency bond. Our analysis shows that the PPP ‘true' financing costs are, on average, 370 basis points above the cost of raising public debt and that the ‘transaction costs' account for around 40% of that financial premium.  相似文献   

14.
Abstract

Despite considerable examination of the impact of telecommunications on travel, little empirical evidence sheds light on the impact of e‐shopping on travel—a recent and increasingly popular form of telecommunications. This paper analyses determinants of online buying and their relationship with in‐store shopping, using empirical data obtained from Minneapolis, USA, and Utrecht, the Netherlands. Based on chi‐square tests and logistic and ordinary least‐squares regressions, the results indicate that online buying is affected by sociodemographics and spatial characteristics of people, their Internet experience, and their attitudes towards in‐store shopping. US respondents who prefer to see products in person are less likely to buy online. Dutch respondents are more likely to buy online as travel times to shops are shorter. At first sight, this counterintuitive result might be related to an urban, innovative lifestyle that supports e‐shopping. A more detailed analysis of Dutch online buyers reveals that they make more shopping trips than non‐online buyers and have a shorter shopping duration. The results indicate that the relationship between online buying and in‐store shopping is not one of substitution but of complementarity.  相似文献   

15.
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   

16.
Goodwin  P.B. 《Transportation》1989,16(2):121-154
Panel data are used to investigate what happens when people have some important transitions or changes in their life-cycle, employment status, income, or car ownership. Only three years data are available, and the pace of transition is slow: as a result relevant sample sizes are rather small. The analysis is carried out in two stages: results are given from a two year period, and these are used to generate hypotheses checked with data from the third year.It is found that in many cases the effects on mobility are different from what would be expected from cross-section data. In particular:
–  - car ownership changes are substantially less than expected;
–  - public transport does not benefit as much as expected when people become members specific dependent or captive groups.
  相似文献   

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This paper provides an overview of tunnelling projects with some of the themes covered by the Chengdu Tunnelling Conference.(a) Environmental issues and tunnels under high groundwater pressure (Hallandsis Rail Tunnel, Sweden)(b) Fire -fighting and tunnel safety on long highway tunnels (Socatop Tunnel, West Paris)(c) Mechanised tunnelling below the world's largest airport (Heathrow T5) of a quality that avoids disruption to its operation.Each of these overviews show an enhanced performance in regard to project specific events or objectives. Particularly in tunnelling, project owners expect more than just a facility delivered on time for their money: they expect an all round performance respecting deadlines, budget, environmental protection, safety, quality and community harmony. Funding agencies do not always have the same agenda as project owners, acknowledging peripheral selection criteria but often demanding that the lowest bidder be awarded work. All round performance requires all round project selection criteria.  相似文献   

19.
1 What is Horizontal Directional Drilling? Horizontal Directional Drilling, accurately steered drilling, has become state -of- the -art drilling technique in the world. Specially- designed directionsteerable corebarrel and accurate direction measurement tool are available for the use together with wire line core drilling machine. That makes it feasible to extract cores and to measure the drill travel line &length while drilling in a curve.  相似文献   

20.
We hypothesise that intra-household interaction influences home departure time and mode choice for the morning commute. In Indonesia, over 71% of vehicles on the road are motorcycles. This fact increases the significance of household interaction in influencing transport mode choice since the simplicity of the motorcycle allows a great degree of versatility in regard to multiple family member transport. To emphasise this point, our study focuses on the unique travel behaviour of adolescents during the school morning commute which, due to the use of the motorcycle, is a combination of the travel behaviour of accompanied children and escorting adults. Our study discovers that adolescents are likely to shift their school arrival time very early or close to the designated starting time in relation to motorcycle-based parental escort to school. In regard to mode choice, adolescent students prefer to be escorted by motorcycle rather than take public transport.  相似文献   

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