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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   

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Given that severe weather conditions are becoming more frequent, it is important to understand the influence of weather on an individual’s daily activity-travel pattern. While some previously rare events are becoming more common, such as heavy rain, unpredicted snow, higher temperatures, it is still largely unknown how individuals will change and adapt their travel patterns in future climate conditions. Because of this concern, the number of research studies on weather and travel behaviour has increased in recent decades. Most of these empirical studies, however, have not used a cost–benefit analysis (CBA) framework, which serves as the the main tool for policy evaluation and project selection by stakeholders. This study summarises the existing findings regarding relationships between weather variability and travel behaviour, and critically assesses the methodological issues in these studies. Several further research directions are suggested to bridge the gap between empirical evidence and current practices in CBA.  相似文献   

4.
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   

5.
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   

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Deep-buried water-storage and drainage shield tunnels, which are different from road and subway shield tunnels in terms of computation theory, construction technology and operation maintenance, would bear high inner water pressure and large earth pressure. In view of the change of the bearing mode for the lining structure of water-storage and drainage shield tunnels, a full-ring test and numerical analysis are carried out to study the influence of inner water pressure, staggered joint assembly and bolt installation types on the behaviors of water-storage and drainage shield tunnels. The results show that the deformation of the straight-jointed water-storage and drainage shield tunnel varies greatly from the state of empty water to that of full water; and the vertical and horizontal convergence deformations of the tunnel with inner water pressure of 0.6 MPa are 2.2 times and 3.2 times of that without inner water pressure, respectively. The convergence deformation, and the maximum joint opening and bolt tension of stagger-jointed lining structure decrease by 15%-25% and 25%- 40%, respectively, compared with that of the straight-jointed water-storage and drainage shield tunnel. The bolts at the segmental joints will yield because of the increase of inner water pressure and the first occurrence of bolt yield phenomenon is located near the position on the lining structure which is under the action of maximum negative bending moment; because the failure of shield tunnel is always caused by the yield of joint bolts, this position is the weak point for the deep-buried water-storage and drainage shield tunnel. For the water-storage and drainage shield tunnel based on the connection with double rows of bolts, the bolts near the outer arc surface of segmental joints in the area of 90 degree in the vault and arch bottom can be removed; the bolts near the inner arc surface of the segmental joints within the 90 degree of the haunch must be installed, otherwise, the tensile force of the bolts at the segmental joint near the maximum negative bending moment will increase by 5%-14%. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

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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   

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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:
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This paper studies the impact of vehicle quota system on the market structure of Singapore’s car distributorship industry. Using recently available data, we analyzed the populations and new registrations of different brands of passenger car and motorcycle. We found an increase in market concentration in the car distributorship industry, as the market shares of the top distributors have increased steadily, even though the annual growth rate of vehicle population is capped at 3% per annum. We also found that average dealership markups for passenger cars for the period August–September 2002 are similar to those reported in earlier studies. We relate these empirical findings to a theoretical model of a differentiated-good oligopoly operating under an industry sales constraint.  相似文献   

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ABSTRACT

While automotive original equipment manufacturers and IT companies are developing and demonstrating self-driving cars, true autonomy will not be realised in the near future due in part to the technology readiness level of the existing systems as well as issues of ethics, security, governance and standards surrounding the implementation of autonomy for road transport. However, advances in cellular phones and networks, satellite-based positioning and communications, cloud computing, combined with a rise in the volumes of available data, allied with a reduction in their costs, offer the very real possibility of connecting vehicles, one to another and to smart city infrastructure as part of the Internet of Things (IoT). Data from connected vehicles, when combined with other information, may provide valuable intelligence to traffic managers and other stakeholders via cooperative intelligent transport system (C-ITS) platforms. Nevertheless, many issues face the implementation of a truly connected IoT in general and C-ITS in particular.  相似文献   

12.
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   

13.
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   

14.
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   

15.
Increasingly, stations are being extended to tunnels due to the effects of topography on mountain rail-ways and the requirements of the stations. A forked tail tunnel arrangement is the most popular one, but the concomi-tant effect of the following tunnel on the antecedent tunnel during construction of a tunnel with small spacing causes cracking of the primary support and secondary lining as well as heaving of the invert, which continues to trouble en-gineers. Different problems are encountered by different tunnels because of the complexities and variations of geo-logical environments. Using the construction of two single-line sections with small spacing for the Xinchengzi tunnel on the Lanzhou-Chongqing railway as an example, the support form for a soft rock tunnel with small spacing and high geostress and deformation, as well as the invert construction sequence of the left and right lines and secondary lining, are analyzed and discussed. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

16.
Light distribution (LD) and installation style of luminaires affect the utilization factor (UF) of luminaires, and the UF affects the luminaire power and road pavement illuminance and further the power consumption of illu- minating system and the luminous effect of road pavement. An UF model of tunnel lighting was established based on the luminaire LD data and installation parameters, in which four LD styles were adopted. For each LD the parame- ters optimization and simulation were conducted regarding four installation styles, e.g. central style, offset-of-vault style, symmetric style and staggered style. The energy-saving and the lighting effects of each LD and luminaire in- stallation style at the tunnel middle zone were studied. The results show that symmetric luminaire installation is the most energy-saving style and has the best lighting effect than the other three luminaire installation styles; the lighting effect of central luminaire installation is the second best; staggered luminaire installation is the most energy-intensive style and has the worst lighting effect except for some special-shaped LD; waterdrop-shaped LD is the most suitable one along transverse direction of tunnel and applicable to the central, offset-of-vault and symmetric luminaire instal- lation styles; symmetric butterfly-shaped LD is the most suitable one along longitudinal direction of tunnel and appli- cable to the central, offset-of-vault, staggered and symmetric luminaire installation styles; with waterdrop-shaped LD along transverse direction and symmetric butterfly-shaped LD along longitudinal direction, they are suitable for the above four luminaire installation styles, and have better energy-saving and lighting effect; as for the LD with symmetric and oblique curve, it’s better for the profile of oblique luminaire distribution to be comply with that along tunnel transverse direction, and it is suitable for the symmetric and offset-of-vault luminaire installation styles. © 2018, Editorial Office of "Modern Tunnelling Technology". All right reserved.  相似文献   

17.
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.
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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   

20.
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   

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