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1.
In spite of a broad consensus among transportation analysts that bus rapid transit, whether operating on exclusive rights-of-way or on uncongested high occupancy vehicle lanes or general purpose limited access facilities, provides higher performance and has significantly lower costs per passenger trip than rail transit in medium and low density cities, nearly all Sunbelt cities are building or planning heavy or light rail systems. This paper reviews previous studies of the cost-effectiveness of heavy and light rail transit with bus-rapid transit and the growing experience with busways and transitways and concludes, once again, that some form of bus rapid transit would be a far more effective way of providing improved transit in these cities than heavy or light rail transit. Not only would bus rapid transit be substantially cheaper, but it would provide a higher quality of service than light or heavy rail transit for virtually all users. Finally, the paper speculates on the reasons for the continued, “blind” commitment to rail transit by policymakers in Sunbelt cities and on the refusal of policymakers in all but a few of these cities to even consider bus rapid transit.  相似文献   

2.
Cities in developing countries like India are facing some of the same concerns that North American cities are: congestion and urban growth. However, there is a sense of urgency in cities like Delhi, India in that this growth is far more rapid as both urbanization and motorization are ongoing processes that have not yet peaked. In this paper, we examine land use change and its relationship with transportation infrastructure and other planning related variables in a spatial context. We estimate land use change models at two different scales from separate data. Cellular automation and Markov models were used to understand change at the regional scale and discrete choice models to predict change at the local level. The results suggest that land use in the Delhi metropolitan area is rapidly intensifying while losing variety. These changes are affected by industrial, commercial and infrastructure location and planners and policy-makers need to better understand the implications of location decisions. We also examine these results in the context of a policy framework for data-based planning that links land use and transportation models for Delhi.  相似文献   

3.
The Peoples Republic of China, with its great urban populations, is finding it necessary to develop a range of strategies to deal with increasing demand for goods and people movement, increasing motorization and the increasing congestion that results from the increasing travel demand. This paper discusses strategies being adopted in two northern cities, Changchun and Shenyang. Both transit and roadway programs are examined for Changchun. Problems and successes of a new toll road are examined for Shenyang. Sustained infrastructure investment is essential to assure the necessary mobility for economic growth.  相似文献   

4.
Los Angeles is well known around the world as an automobile-oriented low density community, yet recent transportation policies have emphasized greater capital investment in rail transportation than in highways, and recent policies have attempted to discourage automobile usage through transportation demand management. While these policies have accomplished small shifts toward public transport and somewhat lower dependence upon singly occupied automobilies for work commuting, the financial costs of these policy changes has been very large in relation to their benefits. Proper pricing of transportation alternatives, more creative use of new and emerging transportation technologies, and the provision of many more opportunities for simpler private sector transport services, would all appear to be more promising as cost-effective approaches to coping with congestion in Los Angeles than the current regional transportation policies.  相似文献   

5.
Changing urban land-use patterns have reduced the importance of traditional downtowns as the origin and destination of numerous vehicular trips. Much traffic on downtown-area freeways seeks merely to get past downtown, thereby worsening the level of congestion for those seeking access to downtown.A number of European cities have begun to develop a new type of transportation facility: congestion-relief toll tunnels in downtown areas. These projects appear to be economically feasible largely or entirely from premium-price tolls paid by users. Hence, they are being developed by private consortia, operating under long-term franchises from government. Other keys to the feasibility of such projects are peak/off-peak pricing structures (congestion pricing), nonstop electronic toll collection, and restriction of use to auto-size vehicles only (to reduce tunnel dimensions and therefore capital investment).Preliminary analysis indicates that congestion-telief bypass runnels for downtown Los Angeles and San Francisco would be economically feasible as private business ventures, if developed along European lines. Similar approaches might be applied to other controversial freeway projects in both cities, and to restructuring Boston's huge and controversial Central Artery/Tunnel project.Congress has already authorized public-private partnerships of this type, permitting private capital and private owner/operation to be used, both for new projects and to rebuild existing highway, bridge, and tunnel facilities. Six states and Puerto Rico have enacted private-tollway legislation under which such projects could be developed and operated.This type of project should be politically feasible, since it offers a way to make significant transportation improvements in impacted downtowns with little or no public funding. While transit proponents may oppose the construction of toll tunnels, highway users are likely to support such projects, and some environmental groups may support this method of implementing congestion pricing in urban areas, because of its potential for reducing air emissions.  相似文献   

6.
With increasing demand for air transportation worldwide and decreasing marginal fuel efficiency improvements, the contribution of aviation to climate change relative to other sectors is projected to increase in the future. As a result, growing public and political pressures are likely to further target air transportation to reduce its greenhouse gas emissions. The key challenges faced by policy makers and air transportation industry stakeholders is to reduce aviation greenhouse gas emissions while sustaining mobility for passengers and time-sensitive cargo as well as meeting future demand for air transportation in developing and emerging countries. This paper examines five generic policies for reducing the emissions of commercial aviation; (1) technological efficiency improvements, (2) operational efficiency improvements, (3) use of alternative fuels, (4) demand shift and (5) carbon pricing (i.e. market-based incentives). In order to evaluate the impacts of these policies on total emissions, air transport mobility, airfares and airline profitability, a system dynamics modeling approach was used. The Global Aviation Industry Dynamics (GAID) model captures the systemic interactions and the delayed feedbacks in the air transportation system and allows scenarios testing through simulations. For this analysis, a set of 34 scenarios with various levels of aggressiveness along the five generic policies were simulated and tested. It was found that no single policy can maintain emissions levels steady while increasing projected demand for air transportation. Simulation results suggest that a combination of the proposed policies does produce results that are close to a “weak” sustainability definition of increasing supply to meet new demand needs while maintaining constant or increasing slightly emissions levels. A combination of policies that includes aggressive levels of technological and operations efficiency improvements, use of biofuels along with moderate levels of carbon pricing and short-haul demand shifts efforts achieves a 140% increase in capacity in 2024 over 2004 while only increasing emissions by 20% over 2004. In addition, airline profitability is moderately impacted (10% reduction) compared to other scenarios where profitability is reduced by over 50% which pose a threat to necessary investments and the implementation of mitigating measures to reduce CO2 emissions. This study has shown that an approach based on a portfolio of mitigating measures and policies spanning across technology and operational improvements, use of biofuels, demand shift and carbon pricing is required to transition the air transportation industry close to an operating point of environmental and mobility sustainability.  相似文献   

7.
Development of mega cities of Pakistan and China has greatly been affected by the growth in urbanization and motorization. The uncontrolled rise in urbanization, motorization, exclusionary planning and disproportionate investment in transportation infrastructure has created a socio-economic imbalance, thereby challenging the issue of equity. This paper focuses on a comparative social equity assessment of urban development, characteristics of supply and demand of transportation and infrastructure systems and the impact of existing strategies over equity in the development of urban and transportation system of Beijing and Karachi. The paper concludes by suggesting some strategies for the development of sustainable and equitable urban transportation systems.  相似文献   

8.
9.
Summary

This paper has reported on a study of relative opportunity—not absolute opportunity. Minimum absolute standards for mobility or accessibility are difficult to justify. Some additional study into the development and application of absolute mobility standards may be warranted.

The application of the mobility evaluation model has primarily focused upon a corridor line‐haul system. Conclusions suggest that such a system will not markedly improve existing transit mobility levels in either the peak hour or the off‐peak. The experimental work has verified this conclusion, and more importantly, it has detailed quantitatively the exact levels and spatial distribution of mobility improvements. However, this study does not include a comprehensive analysis of all methods of mobility enhancement, nor does it undertake a comparison of alternative means of mobility improvement. Certainly other methods to improve access to opportunities should be explored before policy considerations are finalized. These methods include other transit solutions, land use alternatives, socio‐economic policies, and other‐mode transportation alternatives. The accessibility technique and mobility indices approach appears to have general applicability in the analysis of optimal strategies for system evaluation.

Of interest is an examination of alternative feeder transit systems to the corridor line. Additional research with the model might point out the maximum mobility effects expected through improved collector service in the suburbs, with corridor line‐haul to the CBD.

The indices are also readily available for a comparison of mobility patterns for different urban areas. Application of the program to transit and socio‐economic data for a set of cities would yield an indication of the relative mobility levels provided. Such data might be considered as an evaluation criterion for future transit funding by federal officials.

In addition, the model is currently being considered by UMTA as a tool to aid in the evaluation of the equitable distribution of transit system benefits as defined in Title VI of the Civil Rights Act of 1964.25 The mobility output would serve as an indicator of the levels‐of‐service provided to certain disadvantaged urban groups. For this application the computer model is being altered to achieve compatability with the Transportation Planning System (UTPS) computer model package developed by UMTA.  相似文献   

10.
In the countries of the Global South such as India, rapid urbanization and the increase in individual motorization may lead to a predominance of unsustainable commuting patterns. However, urbanization also has important positive effects, including the empowerment of women. This paper examines newly released, spatially disaggregated data on home-to-work commuting by non-agricultural workers in the National Capital Region of India. It aims to understand and compare commuting patterns in urban and rural areas, including choice of travel modes, commuting distances, and gender differentials.The results reveal a tendency observable in urban residents to use individual motorized transport more often both for short and for long trips, although the proportion of individual motorization is far from what it is in the industrial world. Rural areas are characterized by the predominance of non-motorized travel modes and a large share of long trips. The mobility gap between men and women does not appear to increase with literacy. In urban areas, women often choose to commute by car rather than using green modes of transportation (especially in higher-income districts). The paper stresses the importance of the area and gender differentials that need to be taken into account when formulating regional transport policies.  相似文献   

11.
Shiftan  Yoram  Suhrbier  John 《Transportation》2002,29(2):145-168
This paper demonstrates, tests and shows the value of activity-based travel demand models and household sample enumeration forecasting techniques in evaluating the transportation and air quality impacts of travel demand management strategies. Using data from the Portland, Oregon metropolitan area, three transportation policies were evaluated both individually and in combination: transit improvements, pricing, and telecommunications. The activity-based models used in this testing represents a significant improvement to today's "four-step" sequential model systems by providing a deeper insight into the individual decision making process in response to transportation policies. A wider range of impacts is predicted, and indirect effects as well as synergistic effects of such policies are taken into consideration. These models are capable of providing the information needed to improve the linkage of transportation models with emissions and air quality analysis methodologies by improving the prediction of variables that are important to accurately estimating emissions and air quality impacts of transportation actions.  相似文献   

12.
The supply of mass transport has not kept pace with the demand in cities in developing countries due to rapid urbanization and severe resource constraints. Developing countries would benefit from a study of the experience in developed countries regarding organization of mass transport and may adopt a few of the successful techniques. Examples include: unified transport authority; intermodal transfer facilities; subsidy to public transport; light rail transit; and redevelopment of the area around main rail terminals. Developing countries would be able to implement most of these techniques. The possible contribution of developed countries to developing countries lies mainly in the area of rolling stock and advanced signalling for rail based urban transport and in training highly skilled manpower for operation and management.  相似文献   

13.
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   

14.
Experiences with time‐of‐day transit pricing in the U.S. are reviewed in this article and compared to those in other countries. Emphasis is placed on examining ridership, financial and efficiency impacts associated with time‐of‐day pricing, along with highlighting innovative approaches to implementing fare differentials. American time‐of‐day fare structures have been about evenly split between off‐peak discounts, peak‐period surcharges, and programmes involving differential rates of fare increases between peak and off‐peak hours. Although most American operators introduced time‐of‐day differentials to encourage ridership shifts to the off‐peak period, available evidence suggests that they have been only marginally successful in doing so. Off‐peak users were generally found to be far more fare‐sensitive to discounts than peak passengers were to surcharges. Only in a handful of American cities were significant efficiency and financial benefits from time‐of‐day pricing recorded, though in those few places, they tended to be substantial. The most successful American programmes have been those which collect fares on the basis of bus runs and direction of trips (rather than the exact time) and which aggressively market their programmes under the aegis of ‘bargain fares’. It is concluded that useful lessons can be gained by sharing policy insights from experiments with differential transit pricing in both the US and elsewhere.  相似文献   

15.
The determinants of public opinion toward public transit is a little-researched topic, though a better understanding of what makes consumers willing to support transit may reveal which attributes of transit consumers value most. One determinant of people’s willingness to support investments in mass transit may be the price of fuel for transit’s principal competition, the private automobile. In this paper, I examine the relationship between the cost of gasoline and stated willingness to invest public money in mass transit improvements. I hypothesize that fuel price volatility—in addition to price itself—is a determinant of support for more mass transit funding, controlling for other factors. As the price of gasoline becomes more uncertain, the public should, all else equal, support investment in mass transportation, a form of transportation that may provide some measure of protection from the price of fuel. Results suggest a strong effect of price volatility on consumers’ willingness to support transit expenditures.  相似文献   

16.
When compared to large cities in developed countries, the shares of public transportation in most Chinese cities are low. Increasing the competitiveness of urban public transportation remains an urgent problem. A capable evaluation method for public transportation is required to assist the development of urban transit systems. This paper focuses on the bus system. Being devoid of standard criteria, it is difficult to determine the efficiency of a transit system or any bus line using a single evaluation index. This paper proposes a comparative analysis to evaluate bus lines so as to filter out candidates for further optimization. From the viewpoints of transit planning, operation and quality of service, this paper establishes 10 subordinate evaluation indices and then uses geographical information system tools, global positioning system data and smart card data to assist the index definition and calculation. Super-efficient data envelopment analysis (DEA) method is adopted for the proposed single factor and comprehensive evaluation models. Finally, the bus system in Shenzhen, China is used as a case study. The comparable significant results validate the capability of the proposed model.  相似文献   

17.
Modeling commuters’ choice behavior in response to transportation demand management (TDM) helps in predicting the consequences of TDM policies. Although research looking at choice behavior has evolved to investigate preference heterogeneity in response to factors influencing mode choice, as far as we know, no study has considered taste variation across commuters in response to multiple TDM policies. This paper investigates the presence of systematic preference heterogeneity across commuters, in response to the TDM policies that can be explained by their socio-economic or commuting-related characteristics. Analysis is based on results of a stated preference survey developed using a Design of Experiments approach. Five policies were assessed in order to study the impact they had on how commuters chose their mode of transportation. These include increasing parking cost, increasing fuel cost, implementing cordon pricing, reducing transit time and improving access to transit facilities. For the sake of assessing both systematic and random preference heterogeneity across car commuters, a form of the Mixed Multinomial Logit (MMNL) model that identifies sources of heterogeneity and consequently makes the choice models less restrictive in considering both systematic and random preference variation across individuals was developed. The sample includes 366 individuals who regularly commute to their workplace in the city center of Tehran, Iran. The likelihood function value of this model shows a significant improvement compared to the base MNL model, using the same variables. The MMNL model shows that taste variation across the studied commuters results in differences in influences estimated for three policies: increasing parking cost, reducing transit time and improving access to transit. The analysis examines several distributions for random parameters to test the impacts of restricting distributions to allow for only normality. The results confirm the potential to improve model fit with alternative distributions.  相似文献   

18.
Developing a more efficient mass transit system, in highly populated cities, improves the mobility, decreases the dependency of private cars, alleviates traffic congestion, and provides a more environmentally friendly means of travel. Recently, the city of Beijing decided to have a target of becoming as a ‘public-transport city’ with a fascinating mass transit system within a larger plan, of building humanistic, scientific and technological, and green public-transport systems. This work discusses the governance evolution of the mass transit system of Beijing between 1949–2008, comprised of two groups of transit systems, the road surface public-transport system (bus, tram, trolley, etc.), and the subway public-transport system. In addition, a time-series analysis is introduced in an attempt to examine the effect of governance evolution on the two transit systems, and of the impacts of the governance structural changes on the mass transit system. The time-series model is introduced using the annual statistics data of the period 1949–2008. The outcome of the analysis is viewed with precaution because of the incompleteness of the many endogenous and exogenous factors to affect the public-transport demand. Generally speaking it is concluded that the governance evolution provides beneficial effect of the Beijing mass transit activity; however, for satisfying the significant increase of the Beijing city’s travel demand and maintaining sustainable development, the governance-involvement pattern needs to be reformed.  相似文献   

19.
Continued growth and development in the Puget Sound region combined with existing geographic limitations have resulted in a transportation network that is at or near capacity for many hours during every weekday. Single‐occupancy vehicles (SOVs) remain the predominant mode of travel, despite a network of high‐occupancy vehicle lanes and regional transit. Given this situation, considering alternative methods to regulate traffic flow is necessary, and the implementation of a regional congestion pricing system is one such option. Although widespread throughout the world, congestion pricing has only recently been implemented in the United States.  相似文献   

20.
This paper studies the effects of road pricing on land use under different development scenarios (business as usual scenario and transit oriented development scenario) by a quantitative method, which combines the integrated land use and transport interaction model (TRANUS model) with the scenario-planning techniques. Moreover, in order to further analyze the differences of the land use effects of road pricing on traffic analysis zones (TAZs) with different urban form attributes, a quantitative classification method combining factor analysis and cluster analysis is then used to quantitatively classify TAZs. The results demonstrate that the effects of road pricing on the land use of a specific region depend on the urban form attributes of the region. The higher the densities of employments and population, and better street design (high densities of street and intersections) and public transportation condition, the less the region is negatively affected by road pricing, and vice versa. More importantly, rail transit can alleviate the negative impact of road pricing on commercial development and population concentration of the region. Therefore, before introducing a road pricing policy, it is necessary to develop public transport system, especially rail transit.  相似文献   

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