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1.
Environmental assessments are on the critical path for the development of land, infrastructure and transportation systems. These assessments are based on planning methods which, in turn, are subject to continuous enhancement. The substantial impacts of transportation on environment, society and economy strongly urge the incorporation of sustainability into transportation planning. Two major developments that enhance transportation sustainability are new fuels and vehicle power systems. Traditional planning ignores technology including the large differences among conventional, hybrid and alternative fuel vehicles and buses. The introduction of alternative fuel vehicles is likely to change the traditional transportation planning process because different characteristics need to be taken into account. In this study a sustainability framework is developed that enables assessment of transportation vehicle characteristics. Identified indicators are grouped in five sustainability dimensions (Environment, Technology, Energy, Economy and Users). Our methodology joins life cycle impacts and a set of quantified indicators to assess the sustainability performance of seven popular light-duty vehicles and two types of transit buses. Bus Rapid Transit receives the highest sustainability index and the pickup truck the lowest. Hybrid electric vehicles are found to have the highest sustainability index among all other passenger vehicles. A sensitivity analysis shows the proposed sustainability dimensions produce robust sustainability assessment for several weighting scenarios. The results are both technology and policy sensitive, thus useful for both short- and long-term planning.  相似文献   

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This paper asserts the continuing need for a long-range component to urban transportation planning, citing particularly the relationships between short- and long-range planning and the dangers of a single-minded concentration on short-range planning. However, the nature of the long-range planning procedure that is required is substantively different from that of most extant approaches. Some of the specific requirements and capabilities of a new procedure are described, and existing procedures are compared against these.In the latter part of the paper, some of the elements of a new long-range planning procedure are characterized. It is suggested that the procedure be built around a scenario approach to confronting and bounding future uncertainty. Second, the need to incor porate financial forecasting in the process is laid out and related to the scenario concept. Third, the need for travel- and impact-forecasting procedures is recognized and a set of input, output and operating requirements for such procedures are specified. It is suggested that improved sketch-planning tools may fit the requirements to a large extent. It is also suggested that some procedures or models in the process should be synthetic models, not needing calibration for each new application. Finally, a number of requirements are specified for the display and evaluation of planning proposals from this procedure. A major emphasis is placed here on transparency of the process and responsiveness to direct intervention by the decision-maker.  相似文献   

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Recent developments in intelligent transportation systems pose new challenges and opportunities for urban transportation planning. To meet these challenges and to exploit these opportunities, a framework for a new transportation planning methodology has been developed. The methodology operates in a computer environment, called PLANiTS (Planning and Analysis Integration for Intelligent Transportation Systems), designed to facilitate the entire planning process form problem identification, through idea generation and analysis, on to prioritization and programming. To assist in problem identification, PLANiTS provides graphic representation of current conditions, including traffic, air pollution, accidents, and projections of future conditions. A computerized knowledge base, containing information about possible strategies and their effects, and a model base, containing transportation and other analysis models, are used to guide the user in identifying potentially effective strategies and performing the appropriate analysis. To facilitate the use of these tools, PLANiTS provides computer support of group processes such as brainstorming, deliberation, and consensus seeking. PLANiTS is designed for use in urban transportation planning at the local, regional, and state levels; it is intended to support a variety of participants in the planning process including transportation professionals, decision makers in transportation agencies (often local elected officials), citizens, and interest groups. Recognizing that transportation planning is essentially a deliberative, political process, PLANiTS is designed to inform and facilitate, but not replace, the political decision-making process.  相似文献   

6.
When discussing the future of cities, there is a tendency to focus on technology that will make cities and mobilities more sustainable. A bit further down the line the question of understanding or changing everyday practice arises – how to get people to transform their current mobility practice, or to adjust to the technologies introduced. As a key to understanding and changing practice I argue that storytelling plays a crucial role on different scales. In line with this, the concept of structural stories can be used to understand how specific framings of modes of transport guides everyday practices. To illustrate this, I will use the example of a concept of redesigning Copenhagen’s streets. On these streets space is redistributed so that pedestrians, cyclists and busses get more space, and more space is created for public places and city life. Consequently, the space allocated for cars and parking is scaled down.  相似文献   

7.
Urban transportation is identified as a functional element in the broader context of urban facilities and services. From this point of view, the relative merits of separate information systems for transportation planning and general urban planning, as contrasted to unified systems for all urban management functions, are discussed. The overriding need to make the most effective use of urban resources argues strongly for the unification of urban information systems to the greatest possible extent consistent with the special data requirements of various functional programs. The need to identify and correlate data items for very small areal units and to keep current records of the constantly shifting patterns of social and economic activities in urban areas present difficult, but not insurmountable technical problems. However, the most serious barrier to the development and implementation of comprehensive urban information systems is concluded to be institutional, rather than technical, in nature.  相似文献   

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A major problem addressed during the preparation of spatial development plans relates to the accessibility to facilities where services of general interest such as education, health care, public safety, and justice are offered to the population. In this context, planners typically aim at redefining the level of hierarchy to assign to the urban centers of the region under study (with a class of facilities associated with each level of hierarchy) and redesigning the region’s transportation network. Traditionally, these two subjects – urban hierarchy and transportation network planning – have been addressed separately in the scientific literature. This paper presents an optimization model that simultaneously determines which urban centers and which network links should be promoted to a new level of hierarchy so as to maximize accessibility to all classes of facilities. The possible usefulness of the model for solving real-world problems of integrated urban hierarchy and transportation network planning is illustrated through an application to the Centro Region of Portugal.  相似文献   

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This paper traces the development of urban transportation planning in the United States, focusing particularly on the influence that three previous conferences -Sagamore (1958), Hershey (1962), and Williamsburg (1965) - have had on the course of this development. Included also are comments on the current state of the art of urban transportation planning and observations as to its future direction.The Federal-Aid Highway Act of 1934, which authorized the use of 1 percent funds for highway planning is identified as the progenitor of urban transportation planning in the U.S., and two reports based on information developed by the highway planning surveys first funded under the 1934 Act, Toll Roads and Free Roads (1939) and Interregional Highways (1944), are credited with preparing the ground for much of the urban transportation planning that was to follow.The rapid development of home interview survey techniques in the late 1940's and the full-scale introduction of computer technology in the Detroit Area Transportation Study are noted, as is the work of the National Committee on Urban Transportation, which was initiated in 1954 under sponsorship of the Automotive Safety Foundation. In addition to its substantial technical contributions, the NCUT, through its success in mobilizing the cooperative efforts of virtually every major group concerned with urban transportation, stimulated significant gains in Federal-State-local relationships and paved the way for increased Federal aid to cities in solving their local transportation problems.The impact of the 1956 and 1962 Federal-Aid Highway Acts on urban transportation planning is assessed. The substantial contributions, of the Hartford, Sagamore, Hershey, and Williamsburg conferences are discussed, as are their shortcomings. It is noted that many of our present concerns — environmental impacts, relationships between transportation and land use, need for cooperation among all levels of government, the multi-modal nature of urban transportation, and the need for citizen involvement, to name a few — were incorporated in the provisions of either one or another of the Federal-Aid statutes in the 1950's and 60's or appear in the recommendations of the several conferences. That these matters still concern us today is given as evidence that planning has not fully lived up to its promise and responsibility, that more rather than less planning is needed, and that, above all, new leadership to pick up where the old has left off must soon assert itself.  相似文献   

10.
Public involvement in the transportation planning process is an effort to ensure that citizens have a direct voice in public decision‐making. Through shared goals, such involvement enriches the planning, implementation, operation and management process. Various strategies of involving the public in the planning process have been tried in the past thirty years, but the overall effort has been lumpy and at times disappointing. In the last few years some forms of communicative action have been applied, following its appearance in current literature, but we still have a long way to go. This paper has four main objectives. First, it surveys the citizen involvement effort as it is practiced today and the problems it faces. Second, it describes teleogenic systems that are particularly suited for tackling conflictual problems. Thirdly, it presents the interplay of virtuous and vicious cycles in reinforcing or retarding collective decision making. And lastly, the process of harvesting the potential of citizen groups in collective decision‐making through critical systems thinking is described.  相似文献   

11.
In appreciation of the fact that longer-run considerations are particularly important in the development of urban transportation, during the past three decades American transportation planning has been employing increasingly sophisticated approaches to the future. This article discusses four phases in this evolution, with a given focus dominant in each period.During the first period, following on the initial provision of federal government funds for the construction of highways in and around cities, major reliance was based on simple projections of travel demand in metropolitan regions, based mainly on current patterns.This was followed by an approach which focused on an analysis of impacts on transportation systems of projected land uses, based on forecasts of population and economic growth for a target year, on the assumption that facilities were to be provided to move all vehicles that wanted to move from here to there at least possible cost.The third period was characterized by an increasing consciousness of the value of articulating national and local goals in making transportation decisions, going beyond narrow economic and mobility objectives, and including the notion of trade-offs among goals.The most recent period discussed is one characterized by rising interest in futures studies, using methods such as Delphi and cross-impact analysis and approaches such as alternative futures, as well as a search for achieving flexibility in transportation development and for means of limiting resource commitment in the face of the uncertainties of the future (keeping options open).It is pointed out that we still have a long way to go in learning how to evolve feasible images of the future, with associated explicit urban life-style goals, that come to grips with societal variety and conflicting interests.  相似文献   

12.
Transportation improvements inevitably lead to an uneven distribution of user benefits, in space and by network type (private and public transport). This paper makes a moral argument for what would be a fair distribution of these benefits. The argument follows Walzer’s “Spheres of Justice” approach to define the benefits of transportation, access, as a sphere deserving a separate, non-market driven, distribution. That distribution, we propose, is one where the maximum gap between the lowest and highest accessibility, both by mode and in space, should be limited, while attempting to maximize average access. We then review transportation planning practice for a priori distributional goals and find little explicit guidance in conventional and even justice-oriented transportation planning and analyses. We end with a discussion of the implications for practice.  相似文献   

13.
Rising levels of air pollution is a major concern across many parts of the world. In this article, we develop a transportation policy to handle air pollution caused by the heavy flow of traffic in urban areas. In particular, we aim to distribute the traffic flow more evenly through a city, by developing a flow algorithm that computes multiple solutions, each of which accommodates the maximum flow. The paper makes the following contributions to build such a transportation policy: (a) Develops a Pareto-optimal Max Flow Algorithm (PMFA) to suggest multiple max flow solutions. (b) Introduces the notion of k-optimality into PMFA to ensure that the suggested pareto solutions are sufficiently distinct from each other – referred to as Pareto-k-optimal Max Flow Algorithm (k-PMFA). (c) Through a series of experiments performed using the well-known traffic simulator SUMO and by doing emission modeling on the New York map, we could show that our policy distributes the air pollution more uniformly across locations.  相似文献   

14.
Accessibility: measurement and application in transportation planning   总被引:1,自引:0,他引:1  
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15.
A GIS-based planning approach to locating urban rail terminals   总被引:1,自引:0,他引:1  
This paper develops a flexible GIS-based methodology for evaluating the potential locations of terminal park-and-ride facilities along urban rail lines. The methodology differs from political-based approaches and traditional travel demand modeling in its use of an objective measure of accessibility to gage the suitability of a site. The methodology begins by constructing an index of derived demand for rail usage based on the local demographics. Principal component analysis (PCA) is used as a means of constructing an index of derived demand consistent with other passenger surveys. Next, trade areas or commutersheds are calculated for each candidate park-and-ride location based on realistic measures of accessibility and network based drive times, taking into account competition among candidates for riders. Following the analysis, the candidate locations and their commutersheds are delineated and visualized in the GIS environment. In summary, application of this method produces a site-specific suitability index that may be used to rank and compare potential park-and-ride locations. We illustrate how our approach fits within the context of the larger-scale corridor study as a complimentary means of refining the location of urban rail stations. The analysis uses the proposed rail system for Columbus Ohio as a case study. This revised version was published online in June 2006 with corrections to the Cover Date.  相似文献   

16.
The advantages, disadvantages, and issues involved in the panel analysis of travel behavior are discussed. Increased statistical efficiency, possibility of improved prediction, and the ability to observe changes and examine behavioral dynamics, are among the advantages panel data offer. Their disadvantages, on the other hand, stem from the added biases and costs of panel survey, and increased complexity involved in the analysis. Following a discussion of response lags, leads, and other dynamic elements of travel behavior, the paper offers a brief review of statistical methods available for the analysis of panel data. Use of panel data and dynamic models for demand forecasting is then described, followed by sample size, interview frequency, and other considerations in panel survey design and administration.  相似文献   

17.
Abstract

Many urban university campuses are considered major trip attractors. Considering the multimodal and complex nature of university campus transportation planning and operation, this paper proposes a dynamic traffic simulation and assignment analysis approach and demonstrates how such a methodology can be successfully applied. Central to the research is the estimation of trip origindestinations and the calibration of a parking lot choice model. Dynamic simulation is utilized to simulate multiple modes of transportation within the transportation network while further assigning these modes with respect to various mode-specific roadway accessibilities. A multiple vehicle-class simulation analysis for planning purposes becomes a critical capability to predict how faculty and staff who once parked within the campus core choose other nearby alternate parking lots. The results highlight the effectiveness of the proposed approach in providing integrated and reliable solutions for challenging questions that face urban university campus planners and local transportation jurisdictions.  相似文献   

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The purpose of this paper is to discuss various types of behavioral data of potential relevance to transit planning. In particular a distinction is drawn between behavorial information regarding feelings, attitudes, opinions, and the like and more sophisticated types of data dealing with individuals' intentions to respond in certain ways given certain configurations of stimuli (transportation variables). The former is shown to be an important input to incremental planning, i.e., where information as to system performance is desired. The latter is shown to be critical to decisions regarding manipulations of transit system parameters, i.e., where knowledge of the outcome of manipulating system parameters is desired.A methodological example as to how the first type of data — informational level data — can be collected and utilized in system planning is presented. Specifically, data collected along the lines of traditional attitude surveys is collected in an attempt to monitor changes in public satisfaction with the Iowa City, Iowa, bus system before and after major system innovations. Implications of the collection and analytical procedures are discussed.This report was produced as part of a program of research and training in urban transportation sponsored by the Urban Mass Transportation Administration of the Department of Transportation.  相似文献   

20.
Recently, the use of more sustainable forms of transportation such as electric vehicles (EVs) for delivering goods and parcels to customers in urban areas has received more attention from urban planners and private stakeholders. To provide some insights toward the use of EVs, this work develops an optimization framework using portfolio theory, which takes into account the cost and the risks associated with some input parameter uncertainties, for determining an optimal combination of EVs with internal combustion engine vehicles (ICEVs) in urban freight transportation (UFT) over some planning time period. This model can assist an urban freight operator to choose the best investment strategy for introducing new vehicles into its fleet while gaining economic benefits and having positive impacts on the urban environment. When taking into account the risks that are involved, the numerical results show that EVs have the potential to compete with ICEVs in UFT.  相似文献   

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