Continuum modelling of transportation networks

The standard discrete transportation models, which attempt to determine traffic flow on every link of a transportation network, are inapplicable to complex dense urban networks, in view of the amount of computation involved. In this paper we adopt a radically new point of view and construct a family of models based on the assumption of continuous traffic distribution over the network. We derive the flow conservation equations and the equilibrium conditions for user-optimized and system-optimized networks.     

A planning methodology for intelligent urban transportation systems

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.     

Specifications for a new long-range urban transportation planning process

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.     

Multiobjective bilevel optimization for transportation planning and management problems

Many previous studies have formulated the decision‐making problems in transportation system planning and management as single‐objective bilevel optimization models. However, real‐world decision‐making processes always have several social concerns and thus multiple objectives need to be achieved simultaneously. In most cases, these objective functions conflict with each other and are also not simple enough to be combined into a single one. Therefore it is necessary to apply multiobjective optimization to generate non‐dominated or Pareto optimal alternatives. It can be foreseen that the multiobjective bilevel modeling approach can become a powerful, and possibly interactive, decision tool, allowing the decision‐makers to learn more about the problem before committing to a final decision. Such multiobjective bilevel models are difficult to solve due to their intrinsic nonconvexity and multiple objectives. This paper consequently proposes a solution algorithm for the multiobjective bilevel models using genetic algorithms. The proposed algorithm is illustrated, using the numerical example taken from the previous study. It is found that the proposed algorithm is efficient to search simultaneously the Pareto optimal solutions.     

Consumers as participants in transportation planning

Legal requirements for public participation in transportation planning increase the opportunity for transportation consumers to influence the design of systems they will use. However, the implementation of these requirements may also increase the possibility that system design will be dominated by the opinions of outspoken groups. This study postulates that public participation is biased, and seeks to test this proposition using data from an Oregon survey consisting of approximately 2,400 respondents. Using Automatic Interaction Detector and cross tabulation analyses, different participation rates were uncovered for groups identified by demographic, attitudinal and behavioral variables.The authors thank the Oregon Department of Transportation for making the original data for the study available.     

Highway and transportation planning in England

This article presents an overview of highway and transportation planning in England. It covers the division of responsibilities between central and local government; the organisation of the Department of Transport; the planning, financing and implementation of road schemes, both local and national. A very brief review of transport legislation is included.NOTE: This paper was printed before the UK General Election of May 1979. The Department of Transport is now responsible to the Minister of Transport. The Minister has similar responsibilities to those previously exercised by the Secretary of State for Transport as referred to in this paper. The views expressed in this paper are those of the writer and are not necessarily those of the Department of Transport.     

Behavioral analysis and transportation planning: Inputs to transit planning

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.     

Sustainability: A vital concept for transportation planning and development

The current pattern of metropolitan transportation and land development in the majority of countries around the world appears to be increasingly unsustainable from both an economical and environmental perspective. Many factors point to the need for adoption of a new paradigm for sustainable transportation and development in both high and low income countries—burgeoning populations, growing air pollution, limits on global petroleum reserves, limited physical and economic capacity to expand automobile-based transportation systems without community destruction, and the urgent need to limit global CO₂ emissions to slow the pace of global warming. This paper outlines some of the conceptual differences between the current paradigm for transportation planning and an emerging paradigm for sustainable transportation and land development. It compares the US and European patterns of transport and land development, which often inspire transportation decision-makers and planners in developing countries. The paper reviews the patterns of development in the cities of several developing countries, identifying policies than can enhance sustainability.     

A network option portfolio management framework for adaptive transportation planning

A real option portfolio management framework is proposed to make use of an adaptive network design problem developed using stochastic dynamic programming methodologies. The framework is extended from Smit’s and Trigeorgis’ option portfolio framework to incorporate network synergies. The adaptive planning framework is defined and tested on a case study with time series origin-destination demand data. Historically, OD time series data is costly to obtain, and there has not been much need for it because most transportation models use a single time-invariant estimate based on deterministic forecasting of demand. Despite the high cost and institutional barriers of obtaining abundant OD time series data, we illustrate how having higher fidelity data along with an adaptive planning framework can result in a number of improved management strategies. An insertion heuristic is adopted to run the lower bound adaptive network design problem for a coarse Iran network with 834 nodes, 1121 links, and 10 years of time series data for 71,795 OD pairs.     

Design charts for estimating transportation planning statistics from area population

Utilizing data collected for urban transportation studies in Ontario, regression analysis has been used to establish relationships between the daily number of person trips in an urban area and the area population. In particular the number of trips by auto drivers, auto passengers and mass transit riders have been investigated. Further, auto driver trips have been stratified into the following destination trip purposes: return home, work and related business, shopping, social-recreational and miscellaneous. The results of this analysis have been used to prepare a set of design charts. These charts are presented graphically and in the form of a nomogram. The accuracy of these charts has been investigated and found satisfactory for most planning purposes.     

Integrated operations planning and revenue management for rail freight transportation

In the rail industry, profit maximization relies heavily on the integration of logistics activities with an improved management of revenues. The operational policies chosen by the carrier have an important impact on the network yield and thus on global profitability. This paper bridges the gap between railroad operations planning and revenue management. We propose a new bilevel mathematical formulation which encompasses pricing decisions and network planning policies such as car blocking and routing as well as train make-up and scheduling. An exact solution approach based on a mixed integer formulation adapted to the problem structure is presented, and computational results are reported on randomly generated instances.     

Incorporating land use in metropolitan transportation planning

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.     

The state-of-the-art in urban transportation planning or how we got here

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.     

Assessing communicative rationality as a transportation planning paradigm

Communicative rationality offers a new paradigm for transportation planning. Drawing on the literature and lessons from transportation planning practice, this paper describes the characteristics of a “communicative” form of transportation planning and compares them with conventional practices. A communicative rationality paradigm would place language and discourse at the core of transportation planning. The paper argues that it would lead to greater attention to desired transportation ends (goals), better integration of means and ends, new forms of participation and learning, and enhanced deliberative capacity. The paper explains the implications of this paradigm for the role of the transportation planner, the purpose of planning, the planning process, communicative practices, problem framing, and the nature of planning analysis. The paper concludes with an assessment of communicative rationality's ability to promote more effective transportation planning. It seeks to create a dialogue that will support the investigation of new transportation planning processes. This revised version was published online in June 2006 with corrections to the Cover Date.     

Cultural heritage connectivity. A tool for EIA in transportation infrastructure planning

The paper is concerned incorporating landscapes’ ecological and cultural values in infrastructure planning. We focus on cultural heritage connectivity in the context of environmental impact statements in transportation infrastructure planning. Using a case study from south-central Sweden cultural heritage indicators from maps were defined, and a GIS-based automated search tool is developed for analysing cultural heritage connectivity from an antiquarian perspective. Analyses of cultural heritage connectivity can inform about the historical and/or present function of the landscape and its social and economic conditions. While this type of connectivity can be searched out using information from maps, a difficulty lies in communicating the knowledge in an interesting way to non-experts.     

A justice-theoretic approach to the distribution of transportation benefits: Implications for transportation planning practice in the United States

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.