Article Abstracts

Volume 4, No. 1, 2002

A Rural Transit Vehicle Management System and Condition Predictor Model

Michael D. Anderson and Adam B. Sandlin, The University of Alabama in Huntsville

Abstract

In an ongoing effort to improve mobility and quality of life for Alabama’s citizens, a computer database system has been developed to improve the State’s ability to manage and assess the condition of its rural transit fleet. The development of this management program consisted of a physical inspection of all state-owned vehicles. Upon completion of the physical inventory, the research team developed a vehicle inventory database to track Alabama’s public transit vehicles and a data model to predict the condition of individual vehicles. The prediction model is presented as a tool to allow the State Department of Transportation to assign an individual vehicle condition rating for each vehicle, without the cost of a physical inventory. This vehicle rating is intended to support the equitable acquisition and disposal of vehicles reflecting the varied roadway conditions and socioeconomic conditions found statewide.

 

Transit Quality as an Integrated Traffic Management Strategy: Measuring Perceived Service

Matthew G. Karlaftis, John Golias, and Efstratios Papadimitriou

Abstract

Declining ridership, shrinking market share, and increasing operating costs have led many transit systems to adopt quality management strategies. These strategies help transit systems improve and evolve continuously by focusing on the customer (passengers) first. An integral step in adopting quality systems is measuring customer satisfaction. Using questionnaire data from the Athens, Greece, bus and trolley bus systems, this article demonstrates the potential use of structural equation modeling (SEM) for measuring customer satisfaction, and relays useful results regarding perceived service quality. The questionnaire results yield essential information in determining current and near-term requirements and customer expectations, helping set priorities for service improvements, identifying system weaknesses, targeting user groups and identifying their specific needs, and setting performance benchmarks that can be used to compare the system to its competitors and track its performance over time.

 

Decision Structuring and Robustness Analysis in Selecting Urban Transit Alternatives

Isam A. Kaysi and Mohamed-Asem U. Abdul-Malak, American University of Beirut

Abstract

Public policy-makers in many cities worldwide have recognized the need to seek urban passenger transport solutions in the domain of urban transit systems. However, with the availability of many transit technologies and systems, decision-makers need support in identifying the advantages and disadvantages of each system, and in evaluating their suitability for the specific urban context being considered. In this article, the Analytical Hierarchy Process (AHP) is proposed as a decision-support methodology for evaluation of urban transit systems. A hierarchy is proposed for the evaluation of system choice, and an illustrative example is presented. The hierarchy reflects overall objectives of transit systems, which include achieving betterment in the urban transport picture and mitigating possible implementation impediments. On the betterment side, the transit system objectives considered in the hierarchy include appropriate level of service and performance, congestion reduction potential, support of economic development, and flexibility. On the other hand, transit system impediment factors comprise system cost, environmental impacts, and implementation and operation barriers. The article demonstrates the value of the proposed approach in decision structuring for selecting among urban transit alternatives and in providing the facility of analyzing the robustness of the decision with respect to various judgments that are made in the selection process.

 

The Modernization of Routes and New Railway Lines: Different Viewpoints and Instruments for Commercial Objective

Andrés López-Pita and Francesc Robusté, Center for Transportation Innovation, Technical University of Catalonia

Abstract

This article presents the concept of “objective travel time” as a key variable in railway line modernization decision making. The concept tries to achieve a threefold goal: optimization of economic resources, significant presence of the railway in the market share of the corridor, and a positive operational balance. The concept has been successfully applied in the new Rail Investment Program in Spain.

 

Bus Transit Operations Control: Review and an Experiment Involving Tri-Met’s Automated Bus Dispatching System

James G. Strathman, Thomas J. Kimpel, and Kenneth J. Dueker, Center for Urban Studies, Portland State University

Richard L. Gerhart, Kenneth Turner, David Griffin, and Steve Callas, Tri-Met, Portland, Oregon

Abstract

Tri-Met has implemented an automated bus dispatching system (BDS) employing satellite-based automatic vehicle location (AVL) technology. The BDS is capable of facilitating real-time operations control actions to improve service regularity. This article focuses on a service regularity problem that often occurs during peak periods when regular service is augmented by extra-board trips (“trippers”). In this case, “bus bunching” results when regular service trips experience departure delays while trippers depart on schedule. With the aid of BDS information, field supervisors stationed at a key location on Portland’s (Oregon) bus mall used holding, short turning, and reassignment actions to maintain headways on six selected routes. Analysis of their efforts reveals an improvement in service regularity as well as a leveling of passenger loads.