Dial-a-ride with customer operated dispatching

Demand responsive bus operation generally requires some type of manual dispatching. If the volume of traffic is low and few vehicles are in service, the cost of dispatching relative to the total operating costs will be substantial. Consequently, many operators hesitate to introduce a dial-a-ride system.In a joint project between Gothenburg Transport Authority (GS) and Volvo, the latter has designed a device to be fitted to the general telephone system whereby a telephone dial can be used to transmit coded information over the public telephone network to a central recorder. In a dial-a-ride service this device can be used as a robot dispatcher.During a period of 11 weeks in 1976 this device was tested in practical operation in the northeastern part of Gothenburg, the second largest city of Sweden. During the same period a prototype Volvo vehicle for low volume demand was also tested in this dial-a-ride service.During this experiment it appeared that customers easily adjusted to the new procedure of getting their bus. These promising results have led GS to continue the development of this system for large scale operation.At the time of the experiment in Gothenburg, Mr. Elmberg was the director of planning of the Gothenburg Transport Authority.     

Measuring quality of service in dial-a-ride operations: the case of a Canadian city

In many countries, dial-a-ride services are provided by public authorities to elderly and handicapped people who cannot use regular transit. Cost minimization is key to running these services, but one can observe a growing interest in quality measurement and improvement. A first step in improving quality is to define a quality measurement scale specific to dial-a-ride services. A second step is to incorporate quality measurements in mathematical models that serve as a basis for optimization algorithms. To this end, an extensive survey of dial-a-ride users was conducted in Longueuil, the largest suburb of Montreal, Canada. This paper describes the steps of the survey and presents its main conclusions: (1) 56 attributes were identified based on interviews, (2) the questionnaire developed has proved to be reliable and valid, (3) an exploratory factor analysis allowed us to determine 13 dimensions of quality in dial-a-ride services, (4) the most important criteria for users were identified, and (5) population segmenting variables by which subgroups of users can be categorized were also determined. Managerial implications of our results are also discussed.     

Second generation U.S. rail transit systems: Prospects and perils

So far in the decade of the 1970's, commitments have been made to construct a second generation of new rail systems in four urban areas — Atlanta, Baltimore, Miami and Buffalo. In this paper the authors speculate on the prospects and perils that lie ahead for these systems in the context of national and local expectations for rail transit and the experience of the first generation rail transit systems of San Francisco (BART) and Washington.     

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.     

Exact and meta-heuristic approach for a general heterogeneous dial-a-ride problem with multiple depots

Dial-a-ride problems are concerned with the design of efficient vehicle routes for transporting individual persons from specific origin to specific destination locations. In real-life this operational planning problem is often complicated by several factors. Users may have special requirements (e.g. to be transported in a wheelchair) while service providers operate a heterogeneous fleet of vehicles from multiple depots in their service area. In this paper, a general dial-a-ride problem in which these three real-life aspects may simultaneously be taken into account is introduced: the Multi-Depot Heterogeneous Dial-A-Ride Problem (MD-H-DARP). Both a three- and two-index formulation are discussed. A branch-and-cut algorithm for the standard dial-a-ride problem is adapted to exactly solve small problem instances of the MD-H-DARP. To be able to solve larger problem instances, a new deterministic annealing meta-heuristic is proposed. Extensive numerical experiments are presented on different sets of benchmark instances for the homogeneous and the heterogeneous single depot dial-a-ride problem. Instances for the MD-H-DARP are introduced as well. The branch-and-cut algorithm provides considerably better results than an existing algorithm which uses a less compact formulation. All seven previously unsolved benchmark instances for the heterogeneous dial-a-ride problem could be solved to optimality within a matter of seconds. While computation times of the exact algorithm increase drastically with problem size, the proposed meta-heuristic algorithm provides near-optimal solutions within limited computation time for all instances. Several best known solutions for unsolved instances are improved and the algorithm clearly outperforms current state-of-the-art heuristics for the homogeneous and heterogeneous dial-a-ride problem, both in terms of solution quality and computation time.     

An evaluation of Councils on Aging dial-a-ride systems in Massachusetts

In many cities and towns in the Commonwealth of Massachusetts, Councils on Aging are running dial-a-ride services for elderly residents. A survey of these organizations was made to determine the service characteristics of their transportation systems. While the Council on Aging dial-a-rides do not achieve productivities as high as those achieved by public transit dial-a-rides, lower operating costs are achieved on a per hour basis. Thus the costs per passenger trip are very close to those for the public transit systems. The major advantage of the Council on Aging systems is their ability to employ volunteer or inexpensive labor. These systems are thus very attractive in areas with unused volunteer resources.     

System convergence — The potential for an integrated road transport environment

This chapter discusses the potential for co-ordinating developments in Road Transport Informatics (RTI) in what could otherwise be a number of fragmented approaches, in order to approach what the DRIVE programme calls the Integrated Road Transport Environment (IRTE). The discussion is presented with particular reference to European developments such as the PROMETHEUS and DRIVE research programmes, but is intended to encompass possible progress towards worldwide standardisation.The role of consensus formation in Europe in the DRIVE projects SECFO and TARDIS is described. The importance of dynamic route guidance and of automatic debiting systems are highlighted in identifying the likely impetus towards the implementation of RTI systems. Finally, some outstanding issues are presented briefly, and the possible emergence of international standards leading to compatible systems worldwide is discussed.     

Analyzing the preference for non-exclusive forms of telecommuting: Modeling and policy implications

This study examines three models of the individual's preference for home- and center-based telecommuting. Issues concerning the estimation of discrete models when the alternatives are non-exclusive are discussed. Two binary logit models are presented, one on the preference to telecommute from a center versus not telecommuting from a center (adjusted ² = 0.24), and the other on the preference to telecommute from a center over telecommuting from home (adjusted ² = 0.64). A nested logit model is also estimated on the following four alternatives: preferring not to telecommute, preferring either form of telecommuting, preferring to telecommute from home, and preferring to telecommute from a center (adjusted ² = 0.35).The results of the models illustrated the importance of attitudinal measures in measuring an individual's preference to telecommute. Oblique factor scores representing workplace interaction, stress, workaholism, internal control, and commute stress were statistically significant in some or all of the models. Other explanatory variables which were found to be consistently significant were education, job suitability, and age. Most respondents preferred either to telecommute from home or were indifferent between either form of telecommuting, which raises the question as to whether there really is a sizeable market niche to be filled by telecommuting centers, and hence whether they may make a significant contribution to transportation demand reduction.     

Identifying optimal data aggregation interval sizes for link and corridor travel time estimation and forecasting

With the recent increase in the deployment of ITS technologies in urban areas throughout the world, traffic management centers have the ability to obtain and archive large amounts of data on the traffic system. These data can be used to estimate current conditions and predict future conditions on the roadway network. A general solution methodology for identifying the optimal aggregation interval sizes for four scenarios is proposed in this article: (1) link travel time estimation, (2) corridor/route travel time estimation, (3) link travel time forecasting, and (4) corridor/route travel time forecasting. The methodology explicitly considers traffic dynamics and frequency of observations. A formulation based on mean square error (MSE) is developed for each of the scenarios and interpreted from a traffic flow perspective. The methodology for estimating the optimal aggregation size is based on (1) the tradeoff between the estimated mean square error of prediction and the variance of the predictor, (2) the differences between estimation and forecasting, and (3) the direct consideration of the correlation between link travel time for corridor/route estimation and forecasting. The proposed methods are demonstrated using travel time data from Houston, Texas, that were collected as part of the automatic vehicle identification (AVI) system of the Houston Transtar system. It was found that the optimal aggregation size is a function of the application and traffic condition.

Strategic management of organizational turnarounds in the transit industry

The traditional wisdom that there are increasing returns to scale among bus transit systems has been shaken with recent research findings. The implication from the literature is that unless many transit systems restructure along new organizational lines the financial and service provision difficulties will continue. Very few public transit systems have attempted to strategically manage change and turnaround organizationally.The objectives of this research were to identify the salient factors in organizational turnarounds and to determine whether these factors were evident within transit organizations that have attempted to manage change strategically. The author reviewed the corporate turnaround literature and conducted four case studies of strategic planning/management within the transit industry.All four cases exhibited organizational declines or perceived declines as imminent. They initiated turnarounds through reorganizations and efforts at strategic management. The reorganizations that occurred at all four cases were relatively minor, involving some changes in function. Only minor changes in management occurred and commitment to strategic management varied. Strategic objectives were not quantifiable. All of the cases could have improved their communication below the middle-management levels. The measures of performance in general did not relate a specific strategy and program to a particular turnaround effect. Through management commitment and some minor organizational restructuring two cases achieved some degree of turnaround. Total commitment to strategic management, organizational change, adequate communication, and accurate performance measures are keys to definitive turnarounds.     

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.     

A simulation model for evaluating advanced dial-a-ride paratransit systems

This paper presents a simulation system that has been developed to model a variety of technology-oriented dial-a-ride paratransit systems operated in an urban environment. The latest advances in information technologies such as automatic vehicle location (AVL), digital telecommunication and computers have afforded a unique opportunity for public transit agencies to integrate these technologies in their paratransit systems for improved productivity and reliability. This opportunity has also prompted wide spread interest in quantifying the actual benefits that can be attained from such technological enhancement. The primary objective of the simulation model described in this paper was to facilitate the evaluation of the potential effects that these technologies may bring on a paratransit system. The paper discusses the general concepts, models and computational techniques applied in the simulation system, focusing on how various components are modeled and how they interact with each other in the overall simulation framework. The simulation system is applied to evaluate the potential operational improvement that may be attained from the application of automatic vehicle location technology.     

New methods of controlling vehicle ownership and usage in Singapore

Over the years Singapore has introduced several fiscal measures aimed at restraining car ownership and usage and thus preventing traffic congestion. Two new methods have recently been added: the Vehicle Quota System which limits the number of new vehicles registered each month and the Weekend Car Scheme which allows cars to be registered for use during off-peak hours only, with substantial financial savings to the owners. The Vehicle Quota System involves monthly public tenders for Certificates of Entitlement needed to register new cars. Over the past 30 months the cost of COE's has been increasing and now constitutes between 12% and 27% of the on-the-road price of a new car. The fluctuations in the COE premiums for different vehicle categories are presented and analysed. The initial problems and the recent modifications made as a result of public pressure are also described. It seems that the increases in COE premiums are likely to continue under strong economic growth conditions as the demand for cars is more income-elastic than price-elastic.