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1.
This paper assesses comparable urban transport scenarios for China and India. The assessment methodology uses AIM/End-use model with a detailed characterization of technologies to analyze two scenarios for India and China till the year 2050. The first scenario assumes continuation and enhancement, in both countries, of policies under a typical business-as-usual dynamics, like constructing metros, implementing national fuel economy standards, promoting alternate fuel vehicles and implementing national air quality standards. The alternative, low carbon scenario assumes application, in both countries, of globally envisaged measures like fuel economy standards as well as imposition of carbon price derived from a global integrated assessment modeling exercise aiming to achieve global 2 °C temperature stabilization target. The modeling results for both countries show that decarbonizing transport sector shall need a wide array of measures including fuel economy, low carbon fuel mix including low carbon electricity supply. The comparison of China and India results provides important insights and lessons from their similarities and differences in the choice of urban transport options. India can benefit from China’s experiences as it lags China in urbanization and income. Modeling assessments show that both nations can contribute to, as well as benefit by aligning their transport plans with global climate stabilization regime.  相似文献   

2.
Research should be fundamental to transportation as a phenomenon, and yet central to the problems that need to be solved. This paper looks at the history of transportation research in the U.S. with a view toward understanding the bases of past research priorities, and deriving a basis for proposing future priorities. As a result, varieties of research are proposed. They include research which is progressive by criteria of the field during past decades, research which is critical or established as needed by rejection of those criteria, and research which arises as newly required by recent mandates to the field. As the most significant conclusion, it is proposed that research models be built — models which put the understanding of urban structure dynamics ahead of accuracy in forecasting.The authors wish to acknowledge the assistance of Ray Blessing, Department of Urban Studies and Planning, and Thomas McKim, Department of Civil Engineering, M.I.T. This paper has profited from criticism by Professor Daniel Brand. The original version was prepared with support from the National Science Foundation.  相似文献   

3.
Transport demand in western Europe has risen steadily in recent years and the forecasts are that the unrestrained demand will continue to rise in the foreseeable future. This growth has put considerable pressure on the resources available to finance infrastructure investments and to fund what are seen as socially important social services. The recent developments in eastern Europe and the anticipated growth of the post-Communist states will put further strains on the fiscal ability of authorities in these countries to fund transport investments and operations. The outcome has been revisions in the way transport projects are funded. This paper, taking a very broad view of what constitutes a transport project, examines the specific nature of urban transport financing in Europe.  相似文献   

4.
Urban public transport energy use is determined largely by the weight of the vehicle, and frequency of intermediate stops, imposing repeated acceleration/steady running/braking cycles, in which much of the kinetic energy is dissipated. Energy consumed for the same capacity and vehicle performance may be reduced by coasting, cutting vehicle weight, and use of regenerative braking, on electrically‐powered systems, to convert the otherwise wasted braking energy into useful form. Particular attention is paid to the last‐named, identifying results of past experience and recent simulations. Practical constraints limiting the amount of energy actually recovered are discussed, including proportion of vehicle weight braked electrically, receptivity of the supply system, stop spacing and number of vehicles operated simultaneously. Reference is also made to battery vehicles and flywheel energy storage.

It is suggested that considerable scope exists in urban electric rail operation for reduced energy consumption, as existing fleets are replaced by lighter weight vehicles, fitted for regenerative braking. Further savings may come from use of inverter equipment. Rate of fleet renewal may be an important factor. Buses are already much more energy efficient, and dramatic gains are unlikely. However, there is some scope for use of flywheel energy storage, and regenerative braking on trolleybuses.  相似文献   

5.
The paper proposes a binary integer programming model for the computation of optimal traffic signal offsets for an urban road network. The basic theoretical assumptions for the computation of delay on the network are those employed by the main models developed during the last few years. The set of input data coincides with that needed for the Combination Method and its extensions. The model is solved through a branch-and-backtrack method and allows the obtaining of optimal offsets for condensable or uncondensable networks without introducing any special assumption on delay-offset functions, contrary to what occurs within other mathematical programming formulations of the problem. A reduced memory dimension is required by the developed algorithm, which promptly supplies during the computation better and better sub-optimal solutions, very interesting in view of the possible application of the method to real-time control problems. The tests performed show that the method can be applied to networks of practical size.  相似文献   

6.
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   

7.
This paper analyzes the efficiency and political acceptability of road pricing and infrastructure policies targeted at relieving urban congestion. It combines a stylized transport model of an urban road network with a model of the political process that incorporates interactions between voters, citizen interest groups and politicians to explore the possibilities to reach political acceptability for efficient transport policies. In a numerical illustration, the paper compares a set of pricing and investment policies in terms of efficiency and acceptability. The illustration shows how conflicting interests can lead to non-efficient policies being chosen.  相似文献   

8.
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   

9.
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   

10.
据<信息时报>报道,2005年3月20日上午,广州一辆满载乘客的288线路公交车被执勤交警截停,交警以公交车超载为由对司机开出了罚单,除扣除2分外,还罚了200元款.对此,公交司机表示不满,因为在广州很少有不超载的公交车;交警的态度非常明确,按照交通法,公交车属机动车,超载就属违章行为,处罚是按章办事;而广东省政协委员王则楚对此事有不同意见,认为交警要以维护城市公共交通为先,公安部门应重新核定处罚超载公交标准.  相似文献   

11.
An information system is presented which identifies the transportation technologies suited to any one transportation need situation lying in a broad range of such situations. The system is concerned with people movement rather than goods movement. The user of the system specifies the nature and extent of demand, as well as certain service requirements. A transportation technology is identified as suited to a particular need situation when the technology meets the demand and the service requirements, and does so at reasonable cost. The technologies identified by the system as suited to a need situation must be examined to select the one best alternative. This final selection process is not part of the system. This system consists of two tables. Their use is described and examples are given. The procedure used to develop the tables is discussed. The system identifies new transportation technologies (PRT, AGT, etc.) as well as old.  相似文献   

12.
Sarna  A. C.  Hutchinson  B. G. 《Transportation》1979,8(1):73-87
A Lowry-type land use-transport model stratified both by socio-economic group and urban sub-region is described. The parameters of this model are calibrated from a 1969 urban travel survey conducted in Delhi. Parameter magnitudes are estimated for several versions of the model and the qualities of these calibrations are reported. Applications of the calibrated models to the analysis of alternative development concepts for the Delhi urban region are described.  相似文献   

13.
Public transit systems with high occupancy can reduce greenhouse gas (GHG) emissions relative to low-occupancy transportation modes, but current transit systems have not been designed to reduce environmental impacts. This motivates the study of the benefits of design and operational approaches for reducing the environmental impacts of transit systems. For example, transit agencies may replace level-of-service (LOS) by vehicle miles traveled (VMT) as a criterion in evaluating design and operational changes. In previous work, we explored the unintended consequences of lowering transit LOS on emissions in a single-technology transit system. Herein, we extend the analysis to account for a more realistic case: a transit system with a hierarchical structure (trunk and feeder lines) providing service to a city where demand is elastic. By considering the interactions between the trunk and the feeder systems, we provide a quantitative basis for designing and operating integrated urban transit systems that can reduce GHG emissions and societal costs. We find that highly elastic transit demand may cancel emission reduction potentials resulting from lowering LOS, due to demand shifts to lower occupancy vehicles. However, for mass transit modes, these potentials are still significant. Transit networks with buses, bus rapid transit or light rail as trunk modes should be designed and operated near the cost-optimal point when the demand is highly elastic, while this is not required for metro. We find that the potential for unintended consequences increases with the size of the city. Our results are robust to uncertainties in the costs and emissions parameters.  相似文献   

14.
P. Roberts 《Transportation》1972,1(3):307-319
The demand for large-scale interregional transport modelling is growing as the ability to do this type of work increases. There is clearly a promise held out by modelling to answer questions of regional economic growth distribution of benefits and incidence of costs. However, many problems are still to be faced in the design and implementation of these models before these expectations can be fully realized. This paper treats some of these problems with suggestions as to how they can be handled.An early version of this paper was presented by the author at the Seminar on Mathematical and Statistical Analysis of Transportation and Regional Development Planning held in Honolulu, Hawaii in May, 1969 under the auspices of the U.S.-Japan Cooperative Science Program.  相似文献   

15.
16.
Because of a general trend of increasing costs of public transport operations and higher subsidies (in some cases accompanied by falling patronage) the European Conference of Ministers of Transport (ECMT) initiated a study of subsidisation and sought the help of the Transport and Road Research Laboratory. The study, in which eighteen countries took part, was concerned with the aims of subsidy, the sources and conditions attached to subsidy, trends in subsidies and the effect of subsidies on patronage, fares, service levels, costs and productivity.The qualitative information concerning the aims of subsidy was analysed in relation to the likelihood of achieving such aims, taking into account current experience of attempts to switch car drivers to public transport. The quantitative information on trends referred to public transport stage services covering where possible the entire country and relating to the period 1965–77; these data were supplemented by data from 59 cities in different parts of the world collected in the course of a TRRL-sponsored study of travel demand factors. The relationship between patronage and service levels, and between subsidies and various operating factors, including costs and productivity, were studied using regression analysis and the general conclusion reached was that although the major part of the subsidy paid was reflected by reduced fares and improved service levels there may well have been some leakage into higher unit costs and manning levels.  相似文献   

17.
This paper prescribes the parameters of marketing strategy formulation in the context of urban public transport and emphasises in particular the usefulness of the marketing mix and segmentation concepts. A marketing mix comprising the two primary dimensions of service attributes and promotion is advocated, the service attributes to include price, in-vehicle time, mesh density, frequency, reliability and comfort. Three primary trip purpose segments are identified viz. journey-to-work, shopping, and leisure/social trip segments, but these may be expanded into a twenty-four cell matrix once origin-destination and car access factors are included. The sensitivity of demand in these segments is examined mostly by reference to demonstration and experimental project data drawn from the United States and the United Kingdom. For the three primary trip purpose segments demand elasticity is shown to be greater for non-price than for price features; for both price and non-price service features elasticity is shown to be a function of journey purpose being least elastic for journey-to-work trips and most elastic for social/leisure trips. The role of promotion is examined and its importance to the successful marketing of public transport clearly demonstrated.This paper is a condensation of material appearing in The Management of Urban Public Transport: a marketing approach, by P. J. Hovell, W. H. Jones, and A. J. Moran, to be published by Saxon House and Lexington Books in 1975.  相似文献   

18.
Japan's urban transportation system in the major transport spheres   总被引:1,自引:0,他引:1  
The urban areas in Japan have undergone rapid changes in the last two and one-half decades. At the same time, the urban transportation system has been faced with numerous problems which need to be solved urgently. This paper presents the development stage and problems in the three largest metropolitan areas, designated as transport spheres, in Japan. Japan's problems in urban transportation are similar to those of most Western nations with regard to such issues as rapid urbanization, growth in travel, increasing auto ownership, growing transit operating deficits, rising wages and air pollution. The differences are the large modal split of transit from automobile trips, major expansion of the rail transit network, and the large number of transit operators in each urban area in Japan. In addition, governmental policies to help solve the urban transport problems are briefly described. In order to make the policies effective, coordination among government agencies is required. The establishment of a unified government agency is regarded as the first priority in dealing with the urban transport problem. It is expected that the government will offer bold new countermeasures to cope with urban transportation problems.This report was accomplished with the kind assistance of Professor Jerry B. Schneider, Departments of Civil Engineering and Urban Planning, University of Washington, and Mr. Satoshi Inoue, an official of the Ministry of Transport in Japan, who is currently studying at the University of Washington.  相似文献   

19.
A necessary input for the analysis of efficient transport policies is the marginal external cost of each transport mode. This paper studies the marginal external costs of urban transportation. These include the marginal external cost of congestion, accidents, air pollution and noise. The costs are computed for cars, buses, trams, metro and trucks. The methodology is described and applied to the urban area of Brussels for the year 2005.  相似文献   

20.
Najmi  Ali  Rashidi  Taha H.  Miller  Eric J. 《Transportation》2019,46(5):1915-1950

Calibration of a transport planning model system is a complex process. While trial-and-error methods and modelling expertise are still the backbone of calibration of transport models, analytical approaches automating the calibration process can improve the accuracy of the models. Introducing a model to guide modellers in the calibration process of large-scale transport planning model systems is the core of this study, where a systematic model for choosing the most appropriate models and parameters is discussed. The effectiveness of the proposed model is investigated by comparing three scenarios which are built on the Travel/Activity Scheduler for Household Agents model as a large-scale agent-based model system.

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