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1.
This paper examines the evolution of urban transport planning since the 1960′s, identifies the key trends that have influenced such planning, describes the current state of urban transport planning, and speculates on the important characteristics that will influence urban transport planning over the next several decades. Fifteen planning conferences since 1957 are reviewed to show the changing perspectives on planning from the professional community. Ten areas are identified that will provide special challenge to future transport planners—demographic changes, the importance of economic production and market forces for transport system performance, multimodal perspectives for transport planning, adopting an operations focus, an important role for technology, developing a sense of community, laying the groundwork for pricing, integrating transport decision making with growth management, transport planning within a sustainability framework, and providing greater accountability of the decision making and planning processes.  相似文献   

2.
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   

3.
Governments of all persuasions are increasingly seeking the participation of the private sector in the supply of transport facilities and services. Private sector participation in the financing, construction, operation and maintenance of infrastructure is considered a serious option in a number of countries in the search for ways of providing much needed investment which would otherwise be deferred. This paper considers some economic and financial problems in the private sector provision of major road infrastructure within urban areas. The main issues are attaching prices (i.e. tolls) to the provision of the service, the value of government rights which are being given up either permanently or temporarily, and the identification required by the promoters of the cost of capital which is essential information in establishing the risk. Broader environmental and equity issues are not addressed. If the approach to establishing a private presence in a previously public supply context is handled properly from the outset, the benefits can be significant. Contrarily however, the prospects could be quite undesirable if badly managed, despite the presence of an extended public purse.requests for offprints  相似文献   

4.
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   

5.
Historically, computer models have grown in complexity, and consequently have become more difficult to use. At the same time there is a growing need for quick-response methods and techniques for broad-brush policy formulation and decision making. The personal computer and its attendant software offer new means for quantitative sketch planning. This paper illustrates two PC-based applications for quick-response exercises. These involve interactive mapping and data analysis methods for the appraisal and interpretation of transport data, and the development and use of eclectic models for systems analysis and scenario generation. The LAMM and DIAMONDS packages are described, and their use in data analysis is illustrated. The Trends Integrator Procedure (TIP) is used to formulate a simple but versatile model for investigation of developments in an urban retailing system. These packages all run on PC's and offer powerful and adaptive tools for improved transport planning.Nomenclature a i a technical coefficient indicating the influence of the unique factor component (U i ) for factor F i - c ij a technical coefficient relating the influence of factor F i on factor F j - F i the relative change in the level of factor F i - U i the relative change in the unique factor component for F i   相似文献   

6.
A basic mathematical model for evacuation problems in urban areas   总被引:1,自引:0,他引:1  
Real life situations like floods, hurricanes or chemical accidents may cause the evacuation of a certain area to rescue the affected population. To enable a fast and a safe evacuation a basic mixed-integer evacuation model has been developed that provides a reorganization of the traffic routing of a certain area for the case of an evacuation. This basic problem of evacuation minimizes the evacuation-time while prohibiting conflicts within intersections. Our evacuation model is a dynamic network flow problem with additional variables for the number and direction of used lanes and with additional complicating constraints.Because of the size of the time-expanded network, the computational effort required by standard software is already very high for tiny instances. To deal with realistic instances we propose a heuristic approach.  相似文献   

7.
In this paper, stability analysis of traffic control for two-region urban cities is treated. It is known in control theory that optimality does not imply stability. If the optimal control is applied in a heavily congested system with high demand, traffic conditions might not change or the network might still lead to gridlock. A city partitioned in two regions with a Macroscopic Fundamental Diagram (MFD) for each of the regions is considered. Under the assumption of triangular MFDs, the two-region MFDs system is modeled as a piecewise second-order system. Necessary and sufficient conditions are derived for stable equilibrium accumulations in the undersaturated regimes for both MFDs. Moreover, the traffic perimeter control problem for the two-region MFDs system is formulated. Phase portraits and stability analysis are conducted, and a new algorithm is proposed to derive the boundaries of the stable and unstable regions. Based on these regions, a state-feedback control strategy is derived. Trapezoidal shape of MFDs are also addressed with numerical solutions.  相似文献   

8.
The predictive accuracy of the models based on the fundamental relation between journey time and passenger demand can be improved through data disaggregation or route segmentation. Primary reason for this is the improvement in the estimates of stopping delays and delays due to passenger boarding and/or alighting (dwell time). Both Poisson and Negative Binomial model estimates of stoppings for passenger boarding and alighting are shown to improve with disaggregation. These improvements, however, contribute little to the overall predictability of the fundamental models which are useful for gaining insight into the significance and variability of the stopping delays and dwell time, or testing sensitivity to changes in the long term. Site or route specific models of journey times which have better predictive capability exist, and may be used for short-run planning. However, the interchangeability and performance over time of the latter, have to be evaluated before making definitive conclusions.  相似文献   

9.
Allahviranloo  Mahdieh  Bonet  Thomas  Diez  Jérémy 《Transportation》2021,48(3):1125-1148
Transportation - Historically cities are formed to provide interaction and communication opportunities for communities. As cities become smarter, new forms of interactions are formed and the...  相似文献   

10.
This paper develops recommendations for improving in an evolutionary manner the performance of our urban ground transportation systems. The strengths and limitations of present static control technology and current computer traffic signal and freeway surveillance and control systems in urban areas are described. A taxonomy of possible information and control configurations in urban traffic operations is developed. The alternatives in the taxonomy are analysed and used as the basis for recommending specific real time information and control functions for improving, in an evolutionary manner, the performance of urban ground transportation systems. The recommended improvements would allow for the first time a meaningful substitution of operational control for physical (static) capacity increases in urban transportation.  相似文献   

11.
This paper proposes a procedure to evaluate sustainable mobility in urban areas. A set of indicators according to three dimensions of sustainability, i.e., environment, economics, and social aspects, are proposed to evaluate mobility in urban areas. The sustainable mobility evaluation is based on an Index calculated through a weighted multi‐criteria combination procedure. A group of specialists in Brazil was involved in the development of the Index by defining the weights for the criteria. An application of the methodology in the city of Belo Horizonte, capital of the State of Minas Gerais, with 2.24 million inhabitants, is presented to validate the methodology.  相似文献   

12.
Transportation - Crowd logistics is a novel shipping concept where delivery operations are carried out by using existing resources, namely vehicle capacity and drivers from the crowd, thereby...  相似文献   

13.
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   

14.
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   

15.
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   

16.
This paper examines the spatial patterns of population density, household automobile ownership and other socio-demographic variables that affect urban travel, as a function of distance from the central city core. Spatial density functions provide a useful characterization of urban structure, and of its evolution when taken at different time intervals. Analysis of the data from four case cities (Austin, Atlanta, Dallas, Phoenix) for 1960, 1970 and 1980 reveals continuing overall dispersion away from the traditional central core, accompanied by the densification of formerly low-density suburbs. This presents implications for high congestion levels in the densifying suburban communities, comparable to those typically associated with the CBD. In addition, the analysis has captured the continuing growth of average household automobile ownership and revealed a distinct spatial pattern that seems to be robust across the case areas considered, as well as within radial corridors in the one case that was so analyzed (Austin).List of symbols Y gross population density in census tractt - X t distance in miles from the center of tract to the CBD - parameter representing the central business district density - y density gradient parameter - X0, X1, X2, and X3 locations of the knots in a three segment division of the x-axis - Di dummy variable defined for thei-th segment - 1 normally distributed disturbance term,a i,b i,c i,d i,i = 1, 2, 3 — parameters to be estimated - A t area of census tractt  相似文献   

17.
Hensher  David A.  Ton  Tu 《Transportation》2002,29(4):439-457
The Institute of Transport Studies has developed a Transportation and Environment Strategy Impact Simulator (TRESIS) as a decision support system to assist planners to predict the impact of transport strategies and to make recommendations based on those predictions. A key focus of the simulator is the richness of policy instruments such as new public transport, new toll roads, congestion pricing, gas guzzler taxes, changing residential densities, introducing designated bus lanes, implementing fare changes, altering parking policy, introducing more flexible work practices, and the introduction of more fuel efficient vehicles. The appropriateness of mixtures of policy instruments is gauged in terms of a series of performance indicators such as impacts on greenhouse gas emissions, accessibility, equity, air quality and household consumer surplus. In this paper we introduce TRESIS to the research community, focussing on the structure of the system and the diversity of applications. Applications are presented to illustrate the diversity and richness of TRESIS as a policy advisory tool.  相似文献   

18.
This paper investigates a parking reservation mechanism to reduce car cruising to find parking. To consider the benefits for drivers and parking facility providers, we charge drivers for making reservations in addition to parking fees, by introducing a reservation pricing model that makes reservation prices equivalent to the value of saved search time. By modeling the number of vacant spaces as a stochastic variable, and applying binomial pricing methods, parking reservation prices are obtained. Numerical examples based on the data for two parking facilities in Taiwan are given.  相似文献   

19.
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   

20.
Urban bus services still play an important role in the movement of people in Britain, although since the 1950's bus patronage has been declining and costs of operation have been increasing. Most of the urban bus networks in Britain (and to a very large extent the Western World) have developed or evolved over the years and it is sometimes said that, despite the changing conditions of bus transport, few of these bus networks in Britain have undergone major re-organisation. A survey was carried out to ascertain this view and to establish the approaches used by British urban bus operators.Five approaches to the planning of urban bus routes and frequencies have been identified: (1) manual; (2) Market Analysis Project; (3) systems analysis; (4) systems analysis with interactive graphics; and (5) mathematical. Previous research in, and application of, the different approaches are described and examined.Between 1970 and 1980, 82.4% of those British urban operators who responded to the survey carried out some kind of major bus study. The survey results run counter to the view that there has been little recent change in urban bus networks in Britain, but the alleged conservatism of the bus industry appears when the approaches used for re-planning bus services are examined - 71.4% of the operators used a manual approach and only a meagre 28.6% made use of simple assignment techniques to predict the potential passenger impacts of the alternative networks appraised.  相似文献   

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