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1.

A decade of increasing Federal attention to urban transportation needs has culminated in the 1970 Urban Mass Transportation Assistance Act. This Act is intended to provide 10 thousand million dollars over the next 12 years in Federal assistance money to urban public transportation systems. This paper examines the needs of selected U.S. cities as a basis for (1) understanding the vast, various and complex transportation needs of urban areas throughout the country, and (2) assessing the sufficiency of these funds. The sample cities have been placed into three broad categories based on the state of development of their transportation systems. In Category I cities, the essential need is to ensure the survival of bus systems for the use of non‐drivers, or to provide some other viable alternative to the automobile; in Category II cities, the primary needs are to relieve auto congestion and to improve public transportation components, while in Category III cities, the primary need is massive investment to improve and to extend public transportation facilities. It is concluded that the presently intended Federal funding level for transportation will not meet the financial requirements of the Category III cities.  相似文献   

2.
In this paper, we will first review literature of the land use and transportation interaction and then develop a new land use allocation methodology called Three Stages-Two-Feedback Method (Integration Method) for both land use allocation and the transportation policy options with a practical implementation. Then we apply this method in an urban general planning project in China with more than 1.2 million populations. In this project, we evaluated three land use allocation strategies and three transportation policy options using two application tools (with and without feedbacks) using this method implemented in a land use planning system UPlan and a transportation planning system Emme. The results show that the use of the feedback method (Application Two) results in a vehicle distance reduction and the increase in the service coverage area of transit bus stops at the same time. Due to the use of transportation accessibility and the congestion measures with a MSA implementation, the accessibility measure shows a convergent process over iterations. This nice feature can be used for alternative comparisons. Future research subjects are also discussed.  相似文献   

3.
In current practice, very few Metropolitan Planning Agencies attempt to capture the effects of transportation system changes on land use, and the consequent feedback effects on transportation system performance, despite substantial evidence that these effects may be significant. In this paper, we present a case study on the application of UrbanSim, a detailed land use simulation model system, and its integration with a regional travel demand model in the Greater Wasatch Front area of Utah. Like several other metropolitan areas, this region has recently been confronted with legal challenges to proposed highway projects, drawing substantial scrutiny to the land use-transportation connection. We describe the UrbanSim model specification, results from model estimation, and sensitivity analyses conducted with the combined land use and travel model system. The results of the sensitivity analysis suggest that accounting for the land use effects of a regional transportation plan may produce significant shifts in key transportation evaluation measures such as vehicle miles traveled, vehicle hours traveled, and hours of congestion delay.  相似文献   

4.
Environmental analyses of the impact of transportation systems on the environment from the cradle to the grave are rare. This article makes a comparison of various Dutch passenger transportation systems by studying their complete life-cycle energy use. Moreover, systems are compared according to their use of space, costs and travel time. Although the results indicate that no one transportation system out performs others in all of the characteristics, in a multi-criteria analysis of four aspects, the train and bicycle emerge as superior options. This holds regardless of the travel distance considered. Interestingly, the train and bicycle are complementary systems, that together operate within a comprehensive distance range.  相似文献   

5.
This paper reports on a study to develop an energy analysis applications manual for environmental benefit/cost analysis of transportation actions. The manual is intended for state and local transportation agency analysts. The analysis procedure evaluates environmental impacts in energy terms. With energy as a common denominator of impact costs or benefits, the severities of different kinds of impacts are compared and the aggregate severity of a group of impacts is evaluated. A technique for evaluating the economic effects of environmental impacts is also suggested. The energy analysis procedure is briefly illustrated by means of a case study. The research findings indicate that the energy analysis procedure may supplement traditional methods of environmental impact assessment by providing: (i) comprehensive quantifications of individual kinds of impacts or the aggregate environmental impact of a transportation action: (ii) quantitative comparisons of the significance of different kinds of environmental impacts, even enabling comparison of government-regulated impacts with non-regulated ones and of any one category of impact with the aggregate environmental impact; and (iii) a basis for determining dollar values of environmental impacts.  相似文献   

6.
With the publication of the Sydney Area Transportation Study, land-use/transportation studies now have been conducted in all capital cities as well as in the majority of other urban areas with populations in excess of 40.000. A review of these studies is made and a qualitative assessment is attempted of the technical phases —land-use planning, trip-generation, trip-distribution, modal-split, traffic assignment and evaluation. Full summary results of this comparative survey are presented in tabular form, although themes developed in the text are illustrated with specific examples from individual studies. The methodology of land-use/transportation studies has been attacked by some Australian writers. An attempt is made to assess the relevance of these criticisms when applied to the practical planning process in Australia.  相似文献   

7.
The traditional model for mitigating a transportation project’s environmental impacts typically operates project-by-project and delivers the mitigation just-in-time. In contrast, the newer practice of advance mitigation comprehensively assesses and mitigates impacts from one or multiple transportation projects before or during project planning, sometimes long before project construction begins. The practice has gained adherents for its potential to improve ecological outcomes, by better aligning mitigation and conservation goals. Advance mitigation also stands to reduce mitigation costs, an important secondary benefit for transportation agencies with constrained resources. Evidence of cost savings, however, has been piecemeal and anecdotal. This paper advances knowledge of advance mitigation’s financial impacts in two ways. First, it critically assesses the evidence about cost savings realized through advance mitigation, both through avoided up-front costs and reduced project delay. Second, it directly estimates the project time savings that might accrue with advance mitigation of state highway projects in California. Overall, the balance of evidence is encouraging for transportation agencies that would introduce the practice, and general agreement exists on its financial benefits. Considering project delays related only to the environmental process, we estimate advance mitigation could reduce delivery times by 1.3–5.0 months per project. Still, we also identify factors limiting comprehensive analysis. Transportation agencies adopting advance mitigation practices into their operations could use a pilot approach that includes rigorous environmental and mitigation cost accounting; such pilots would build needed empirical evidence of advance mitigation’s financial and ecological outcomes.  相似文献   

8.
Three design problems are discussed in this article. First, it is shown that the network design problem with congestion reduces to an all-or nothing traffic assignment problem under some assumptions on the congestion function and the investment cost function. Second, the land use design problem is formulated as an extension of the Koopmans-Beckmann problem and a heuristic is proposed to solve this problem. Third, it is shown that the seemingly more complex problem of designing jointly a land-use plan and a transportation network reduces to a pure land-use design problem. All that is needed to solve the joint optimization problem is a shortest path algorithm and a heuristic to solve the land use design problem. Computational experience is reported for each algorithm.  相似文献   

9.
The lack of relevant information is a significant barrier when policy makers try to motivate local communities in regional transportation–land use planning. This article demonstrates a workable approach to overcoming this information gap. Large data sets and research results are preprocessed to provide the information on regional transportation–land use connections. Web-based open source geo-spatial technologies are employed to reduce the cost of information dissemination while maintaining a high level of accessibility. Maps and graphs are dynamically generated to ensure that relevant information is delivered in easy-to-understand formats. Two illustrative examples are presented in this article to show how local planners can possibly benefit from this approach when developing stories of community growth, accessibility, mobility, and transportation–land use connections in a regional context.  相似文献   

10.
This paper discusses the potential for energy savings in heating and ventilation of light rail vehicles. We present the results of a detailed monitoring campaign on one articulated tram in Ghent, Belgium. The results give insight in the energy use for heating and ventilation in light rail as a function of ambient weather conditions. After several months of monitoring, changes in the HV strategy were implemented and the monitoring was continued. Based on this monitoring data, an energy-use model was constructed for HV both before and after the heating and ventilation strategy changes. These models then served as input for a Monte Carlo simulation, providing average energy savings over 1 year as a result of the optimized heating and ventilation strategy.  相似文献   

11.
Transportation congestion is reaching intolerable levels in many urban and suburban areas in the US. Reliance upon traditional responses, such as transit and new highway capacity, is not working — especially in suburban areas. Although methods for dealing with suburban congestion are often different, there are a number of common features that must be considered in developing short term as well as more permanent and long lasting solutions. In proposing short term solutions, a Menu of Actions is described. It includes transportation actions (the traditional transit and transportation management options) where there are opportunities for getting more out of the existing systems; land use/growth management actions which will result in more rational land use-transportation interactions; financial incentives, to encourage or discourage appropriate actions; more comprehensive and systematic land use and transportation planning; and the organizational and institutional actions required to implement rational solutions.While the Manu of Actions provides a broad array of possible actions to provide relief in the short run, over time the growth in traffic is likely to outpace their effectiveness. Consequently, longer term and often more difficult solutions must be considered and implemented as appropriate. They could include changes in land use development and land use management policies; changes in lifestyle and business practices; improvements through technological innovation; changes in the traditional ways of providing transportation services; and greatly expanded research and development.  相似文献   

12.
This paper presents the first analysis on how financial savings arising from energy efficient ships are allocated between owners and those hiring the ships. This as an important undertaking as allocation of financial savings is expected to have an impact on the incentives faced by ship owners to invest in more energy efficient vessels. We focus on the dry bulk Panamax segment as it contributes to around 50 Mt (5%) of total CO2 emissions from shipping in 2007 and therefore its importance in terms of environmental impact should not be neglected. The time charter market represents a classical example of the principal–agent problem similar to the tenant–landlord problem in the buildings sector. We discovered that on average only 40% of the financial savings delivered by energy efficiency accrue to ship owner for the period 2008–2012. The finding that only part of the savings are recouped by shipowners affecting their incentives towards energy efficiency could consequently have implications on the type of emission reduction policies opted at both, global and regional levels.  相似文献   

13.
In this paper, we define the online localized resource allocation problem, especially relevant for modeling transportation applications. The problem modeling takes into account simultaneously the geographical location of consumers and resources together with their online nondeterministic appearance. We use urban parking management as an illustration of this problem. In fact, urban parking management is an online localized resource allocation problem, where the question is how to find an efficient allocation of parking spots to drivers, while they all have dynamic geographical positions and appear nondeterministically. We define this problem and propose a multiagent system to solve it. The objective of the system is to decrease, for private vehicles drivers, the parking spots search time. The drivers are organized in communities and share information about spots availability. We have defined two cooperative models and compared them: a fully cooperative model, where agents share all the available information, and a “coopetitive” model, where drivers do not share information about the spot that they have chosen. Results show the superiority of the first model.  相似文献   

14.
15.
This paper describes the results, to date, of an effort to integrate a land use model with a transportation network model for the purpose of analyzing the interrelationships of transportation facility development and land development. In the system which has been developed each model provides input to, and receives feedbacks from, each other model. To the author's knowledge, the effort described here represents the first successful attempt to develop and test an integrated model package involving these reciprocal relationships. The results obtained from preliminary runs of this package should be of considerable interest to both transportation planners and land use planners. With this integrated system it has been possible to observe the interrelationships, and in particular the feedbacks, between land use and levels of traffic on the networks. Preliminary results indicate that congested networks produce tendencies toward metropolitan centralization. Attempts to relieve congestion seem to produce metropolitan decentralization and increased travel which lead, in turn, to metropolitan sprawl and increased spread of congestion.  相似文献   

16.
To enhance the efficiency of intermodal transportation for large quantities of goods, the current sea–land transportation system has been reviewed and systematically analyzed, and a bottleneck is pinpointed in the linkage or goods transfer between the waterway and railway. The bottleneck impacts the efficiency of the goods through transportation combining the two modes. To eliminate the existing bottleneck and inefficiency towards intermodality, a new type of flexible double-rail track has recently been invented together with innovations both in trestle bridges and in train ferries. The outcomes of the research in progress show that the flexible double-rail track is feasible from the viewpoints of both geometry and engineering mechanics, it can be used to improve the compatibility of a trestle bridge with various types of train ferries and hence it can support the development of train ferries on a large scale. Based on the innovations, an integrated sea–land transportation system model is proposed as a systematic solution, which is expected to effectively overcome the existing bottleneck and to enhance the efficiency of the whole sea–land combined transportation. Further research on this system model and its major components is also addressed in the paper.  相似文献   

17.
This paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model system consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD. In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is also examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance. While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited to some extent due to data availability, the results clearly indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling  相似文献   

18.
In spite of the fact that about 70% of Nigeria's population live in rural areas, these areas have remained largely inaccessible. Not only do they lack motorable roads and organized public transport but also field surveys indicate that nearly all rural inhabitants do not have a private car. A Directorate of Food, Roads and Rural Infrastructure has been set up to manage the inaccessibility problem, among others. Whereas there are several conventional approaches to the management of the rural transportation problem, the Nigerian approach relies on the provision of roads. This restrictive approach with an emphasis on locational to the neglect of personal accessibility has various limitations which are analysed.  相似文献   

19.
20.
This paper presents a system dynamics approach to simultaneous land use/transportation system performance modeling. A model is designed based on the causality functions and feedback loop structure between a large number of physical, socioeconomic, and policy variables. The model consists of 7 sub‐models: population, migration of population, household, job growth‐employment‐land availability, housing development, travel demand, and traffic congestion level. The model is formulated in DYNAMO simulation language, and tested on a data set from Montgomery County, MD. In Part I: Methodology, the overall approach and the structure of the model system is discussed and the causal‐loop diagrams and major equations are presented. In Part II: Application, the model is calibrated and tested with data from Montgomery County, MD. Least square method and overall system behavior are used to estimate the model parameters. The model is fitted with the 1970–80 data and validated with the 1980–1990 data. Robustness and sensitivities with respect to input parameters such as birth rate or regional economy growth are analyzed. The model performance as a policy analysis tool is examined by predicting the year by year impacts of highway capacity expansion on land use and transportation system performance. While this is a first attempt in using dynamic system simulation modeling in simultaneous treatment of land use and transportation system interactions, and model development and application are limited due to data availability, the results indicate that the proposed method is a promising approach in dealing with complex urban land use/transportation modeling.  相似文献   

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