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1.
Although ridesharing can provide a wealth of benefits, such as reduced travel costs, congestion, and consequently less pollution, there are a number of challenges that have restricted its widespread adoption. In fact, even at a time when improving communication systems provide real-time detailed information that could be used to facilitate ridesharing, the share of work trips that use ridesharing has decreased by almost 10% in the past 30 years.In this paper we present a classification to understand the key aspects of existing ridesharing systems. The objective is to present a framework that can help identify key challenges in the widespread use of ridesharing and thus foster the development of effective formal ridesharing mechanisms that would overcome these challenges and promote massification.  相似文献   

2.
The paper describes some of the key issues that need to be addressed in the design and execution of underground structures to ensure their long term suitability as watertight units and outlines through practical examples of structures that have not achieved their design requirements which situations need to be considered. Waterproofing is not an exact science but a combination of theoretical knowledge and practical experience based on the five key factors: Environment, Design, Materials, Application and Use of the Structure.In conclusion the paper outlines the advances in crack control to date that can provide the necessary long term guarantees.The adoption of re - injectable crack inducers permitted the Client to save over 10% on construction costs and reduced the construction time by six months.  相似文献   

3.
ABSTRACT

Shared ride services allow riders to share a ride to a common destination. They include ridesharing (carpooling and vanpooling); ridesplitting (a pooled version of ridesourcing/transportation network companies); taxi sharing; and microtransit. In recent years, growth of Internet-enabled wireless technologies, global satellite systems, and cloud computing - coupled with data sharing – are causing people to increase their use of mobile applications to share a ride. Some shared ride services, such as carpooling and vanpooling, can provide transportation, infrastructure, environmental, and social benefits. This paper reviews common shared ride service models, definitions, and summarises existing North American impact studies. Additionally, we explore the convergence of shared mobility; electrification; and automation, including the potential impacts of shared automated vehicle (SAV) systems. While SAV impacts remain uncertain, many practitioners and academic research predict higher efficiency, affordability, and lower greenhouse gas emissions. The impacts of SAVs will likely depend on the number of personally owned automated vehicles; types of sharing (concurrent or sequential); and the future modal split among public transit, shared fleets, and pooled rides. We conclude the paper with recommendations for local governments and public agencies to help in managing the transition to highly automated vehicles and encouraging higher occupancy modes.  相似文献   

4.
Four organised car sharing schemes (the YORKSHARE schemes) were established and monitored in West Yorkshire between 1979 and 1981. Three of the schemes were based on a employment sites and one on a residential suburb. Differences in site characteristics and in procedures allowed conclusions to be drawn as to the determinants of scheme performance and impact on the transport system. The proportion of the target population participating in new car sharing arrangements as a result of the YORKSHARE promotion varied from 2% to less than 0.5%. Impacts on car use for the work journey were minor and the main result was an abstraction of public transport patronage. The indirect impacts of car sharing appeared to be unimportant. The paper reports on a detailed analysis of costs and benefits and includes comments on the proper role of ridesharing promotion within transport policy.  相似文献   

5.
ABSTRACT

The deployment of smartphone-operated, non-station-based bicycle fleets (“dockless” or “free-floating” bikeshare) represents a new generation of bikesharing. Users locate bikes in these free-floating systems using Global Positioning Systems (GPS) and lock bikes in place at their destinations. In this paper, we review current free-floating bikesharing systems in North America and discuss priorities for future research and practice. Since launching in 2017, free-floating bikeshare has expanded rapidly to encompass 200+ systems operating 40,000+ bikes within 150+ cities. In contrast with previous systems, free-floating systems operate almost exclusively using commercial “for-profit” models, amidst concerns of financial sustainability. Governance for these systems is in early stages and can include operating fees, fleet size caps, safety requirements, parking restrictions, data sharing, and equity obligations. We identify research and practice gaps within the themes of usage, equity, sharing resources, business model, and context. While some existing bikesharing literature translates to free-floating systems, novel topics arise due to the ubiquity, fluidity, and business models of these new systems. Systems have numerous obstacles to overcome for long-term sustainability, including barriers common to station-based systems: limited supportive infrastructure, equity, theft or vandalism, and funding. Other unique obstacles arise in free-floating bikeshare around parking, sidewalk right of ways, varied bicycle types, and data sharing. This review offers background in and critical reflection on the rapidly evolving free-floating bikeshare landscape, including priorities for future research and practice. If concerns can be overcome, free-floating bikeshare may provide unprecedented opportunities to bypass congested streets, encourage physical activity, and support urban sustainability.  相似文献   

6.
Milan Janic 《运输评论》2013,33(1):81-104
Abstract

This paper presents a review of the research on the sustainability of transport systems carried out over the last 15 years for the European Union (EU), identifies some missing gaps and elaborates on the prospective future ideas. The general concept of sustainable development and definitions of sustainability of transport systems and their operationalization are discussed. These are followed by the general review of the research on the sustainable transport systems funded by the EU 4th, 5th and 6th Framework Programs. Consequently, refinement of existing and/or developing an innovative system for monitoring sustainability of transport systems in the EU based on the indicator system(s) of performances is suggested as a prospective research idea.  相似文献   

7.
Martin Wachs 《Transportation》2013,40(6):1159-1172
North American urban areas have changed dramatically over the last four decades. While downtowns were thought to be in long-term decline 40 years ago, central business districts are today the most vibrant residential and commercial centers throughout a largely suburban continent. This paper examines the role of transportation technology and policy in the earlier decline and recent revival of American downtowns and examines challenges to the continuation of urban regeneration. Major recent investments in physical improvements in central cities have been complemented by a dramatic shift in the locus of logistical and goods processing activities from city centers to outlying areas. While many tout the energy efficiency and environmental benefits of walkable and denser inner cities, a more complete accounting of their impacts also requires analysis of increasing urban congestion and the steady rise in urban goods movement in support of the new development patterns.  相似文献   

8.
Because of different geo‐demographic and economic conditions, the impact of the new passenger modes (road and air) on rail travel was much larger in North America than in Europe. In 1960s and 1970s, as the railway share of intercity traffic in North America shrunk to a negligible one or two percent, the passenger trains were abandoned by private railway companies and taken over by state organizations, which have continued to operate traditional trains and generate mounting losses. On the technology side, no attempts have been made to improve competitiveness of trains vis‐a‐vis automobiles and airplanes.

In Europe and Japan, the railways responded to the challenge by (i) upgrading the performance (speed) and comfort of traditional trains operating on existing tracks and (ii) developing trains which could, on short and intermediate range distances, compete successfully, in terms of speed and economy, with the road and air modes. The Japanese (Shinkansen trains) and French (TGV trains) experience clearly shows that trains operating on dedicated lines at average speeds of 150 to 200 km/hr provide a superior transportation service and economy on high‐traffic intercity routes of up to about 500 km length. In this paper the factors responsible for the present status of passenger rail in North America are analysed, the current policies in the U.S. and Canada are evaluated in the light of experience to date and developments abroad, and suggestions for a long‐term passenger rail policy are made. This includes examination of (i) the viability of continued subsidization of traditional train services, (ii) the viability of operation of faster trains on existing tracks, (iii) the scope for introduction of modern, fast trains on dedicated lines in high‐density, intercity corridors, (iv) the application of fast trains as access to major airports and integration of airports with fast intercity lines, and (v) the impact of energy (oil) consumption in transportation.

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9.
Abstract

Transit agencies are consistently trying to improve service reliability and attract new passengers by employing various strategies. Previous literature reviews have focused on either passengers' or transit agencies' perspectives on service reliability. However, none of the earlier reviews have simultaneously addressed these differing perspectives on service reliability in an integrated manner. In response to this gap in the literature, this paper first reviews previous work on passengers' perspectives of transit service reliability and their response to service adjustments made by different agencies. Second, it analyzes transit agencies' plans and reports regarding their reliability goals and used strategies in order to improve service reliability, while looking at the impacts of these strategies on service. Reviewing these two parts together provides a needed contribution to the literature from a practical viewpoint since it allows for the identification of gaps in the public transit planning and operations field in the area of reliability and provides transit planners and decision makers with effective and valuable policy-relevant information.  相似文献   

10.
The current situation of suburban rail services is reviewed. Differences between seemingly similar services—urban transit, commuter service, suburban rail service and regional rail -are discussed. The suburban rail commuter is described as the true intermodal traveler. Differences of the political backgrounds of the inner-city compared to the suburbs complicate implementation of programs to improve service and suggest deep problems over the long term. Because the transition of suburban rail service from the private to public sector has been so recent, it is difficult for many to recognize that the profit of the service is in the lower total transportation costs for the community as compared to a cash dividend. Existing railroad lines in many cities have the potential of being a cost-effective solution to traffic problems, although the specific solutions vary widely, ranging from the operation of new commuter trains over the lines of a heavy duty railroad (Toronto) to a completely new light rail system (San Diego).  相似文献   

11.
There are debates about whether job-housing balance and short commuting distances could be achieved through government intervention in Western countries. However, few studies have been carried out in developing context. The present study aims to fill in this knowledge vacuum by studying how China’s changing socio-spatial context, particularly the spatial ideas of danwei, influences job-housing relationships and commuting patterns from a historical perspective. The results clearly show that the dominant trend in commuting patterns in Chinese cities has changed from intra-danwei commuting before 1978 to reverse commuting from the city center to the inner suburbs in 1978–1998, to long-distance suburb-to-city commuting since 1998. The findings suggest that government intervention could be helpful in achieving shorter commute in China, and that urban planning and policy that promote mixed land-use and job-housing balance should be considered. Some limitations of government intervention are also discussed.  相似文献   

12.
Speed limits had been centralized at the federal level since 1974, until decisions were devolved to the states in 1995. However, the centralization debate has reemerged in recent years. This paper conducts the first econometric analysis of the determinants of speed limit laws and State reactions after the repeal. By using mobility, geographic and political variables, our results suggest that geography - which reflects private mobility needs and social preferences -, is one of the main factors influencing speed limit laws, together with political ideology. Furthermore, we identify the presence of regional and time diffusion effects. By presenting first evidence on policy determinants, we provide a better understanding of the formulation of the heterogeneity of speed limits in US and offer implications for the debate on centralization and decentralization of transport policy.  相似文献   

13.
As from January 2020, the International Maritime Organization (IMO) is implementing a global 0.5% limit on the sulphur content of fuel, commonly known as the global sulphur cap. This limit is the latest policy in the efforts to reduce sulphur emissions from shipping, following the designation of emission control areas (ECAs) and other regional regulations. In this paper, a literature review is conducted of academic studies that have dealt with issues relating to the reduction of maritime sulphur emissions. Various recurring research themes are identified, spanning the areas of operations research, maritime economics and transport policy. The effects and implications of available compliance options are then analyzed from the perspectives of ship operators, shippers and consumers. Using lessons learned from the enforcement of ECA regulations, this is followed by an appraisal of various potential issues related to the enforcement of these new global regulations. It is found that a homogeneous enforcement regime is required to ensure a level playing field amongst ship operators and that the global sulphur cap may lead to serious market distortion, due to the potential short term rise of fuel prices. The paper concludes with a set of recommendations for future research on sulphur emissions from shipping in the aftermath of the global cap and, looking forward, to its relationship to the IMO strategy on the reduction of greenhouse gas (GHG) shipping emissions.  相似文献   

14.
Changes in the economic and demographic characteristics of US cities over the past two decades have modified but have not diminished the need for extensive public transportation service in these areas. The vast bulk of trips to work, to shop, and for most other purposes within large American cities are still made by residents of those cities, a significant portion of whom do not own or have access to an automobile. Expensive and far-ranging programs to enhance surburban commutation to the central city by means of rail rapid transit do little to meet the needs of those who still must rely upon local, extensive service within the city.One form of public transport — the taxicab — offers the quality and flexibility of service which even those of limited means find well worth the price. As a consequence, fleet taxicabs serve almost 40 percent more passengers than all US rapid transit systems and about 60 percent as many passengers as all bus transit systems. Removal of archaic and restrictive regulations governing the number and use of taxicabs in major US cities would promote more effective and widespread use of this, the only form of public transit that still operates — at a profit — without public subsidy.  相似文献   

15.
Abstract

This paper explores user satisfaction with making use of paratransit in Bandung, Indonesia. User perceptions of attributes are analyzed using factor analysis to find representing attribute types and factors of service quality. Ordinal probit analysis is employed to explore the characteristics of users regarding their perception of satisfaction with the paratransit service. Binary logistic analysis is undertaken to predict users’ choice probability in making use of paratransit in the future when there is a service improvement. The study reveals that what may be of importance in developed countries carries a different weight of importance for paratransit users. This fact can be explained by describing the characteristics of users that expressed their satisfaction, which also explains the target market for this mode. The analysis reveals the notion that financial motives seem to dominate when users select to use paratransit.  相似文献   

16.
就目前我国已建成运营的3条市郊铁路——北京S2号线、上海金山线、成都成灌线来看,市郊铁路存在着定价机制单一、票价水平偏低等问题,地方政府补贴负担沉重,市郊铁路定价面临着经营与竞争的双重压力。针对这些问题,本文从加快市郊铁路规划、探索多元化投融资机制、在运营环节引入市场化机制等方面提出完善市郊铁路定价机制的政策建议。  相似文献   

17.
18.
Transportation - In Charlotte, North Carolina less than one half of 1% of commuters ride a bicycle to work despite several decades of public investment in bicycle infrastructure and planning. Like...  相似文献   

19.
本文从政策法规、市场环境、安全管理等方面对我国主要省份的包车客运发展现状进行分析,提出了我国包车客运在概念、运力投放、标志牌管理、客运市场和行业监管等方面存在的问题,最后从标准体系建设、运力规划、准入退出、经营模式、信誉考核和信息化等方面对我国包车客运管理提出建议。  相似文献   

20.
As a capital intensive transport technology linked to industrialized economies, containerization has only recently penetrated the non-Western, developing periphery. The spatial spread of this revolutionary technology through the transport surface of a developing region encounters numerous institutional and technological barriers which are only removed by a reformulation of government trade and transport policies. In examining the spread process of container technology at the Port of Belawan and its hinterland of North Sumatra, Indonesia, attention is given to the important role of policy as a catalyst to the spatial penetration of this foreign imposed transport mode. Some negative consequences of technology adoption are explored and a spatial penetration model of container technology in a developing regional economy is proposed.  相似文献   

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