Defining the functional and physical compatibility of a modernized tramway rolling stock with a newly planned LRT system: a case study of Belgrade

According to the Belgrade Master Plan for 2021, the public transportation system for the city and its region will include three rail modes: a modernized existing tramway, regional rail, and a new light rail transit (LRT) mode. In the coming years all three rail modes should be developed simultaneously and in a coordinated manner. The introduction of LRT is to be realized in several phases, and its first line will partially follow the alignment of an existing tramway line. As the present tramway vehicles are obsolete, new rolling stock must be designed and purchased to be compatible with many of the elements of the LRT. Ways to adjust the new tramways to the LRT rolling stock represent the central topic of this paper. The basic technical and operating characteristics of the new tramway are defined with respect to their required compatibility with the LRT stock and infrastructure.     

Commuter impacts and behavior changes during a temporary freeway closure: the ‘Fix I-5’ project in Sacramento,California

One mile of Interstate 5 (I-5) in downtown Sacramento, California was closed intermittently for reconstruction (‘the Fix project’) over nine weeks in 2008. We analyze the impacts of the Fix on commuters’ travel behavior, as measured through two contemporaneous Internet-based surveys. The impacts of the Fix on traffic conditions do not appear to have been excessive: majorities in all relevant subsamples did not find conditions worse than usual, and sizable minorities actually found them to be better. Among the active changes to commute trips, the easiest options – avoiding rush hour and changing route – were the most common (adopted by 48% and 44%, respectively). Among the changes that reduced vehicle-miles traveled, increasing transit use and increasing telecommuting (TC) were the most common (each adopted by 5–6% of the relevant subsample). Binary logit models of these two choices suggest that persuading current adopters to increase their frequency of use is easier than convincing nonadopters to start TC or switch to transit. Women and those in larger households were found to be more likely to increase TC and transit use. Employer support of commute alternatives significantly influenced the adoption of both strategies.     

A methodology to derive the critical demand density for designing and operating feeder transit services

Feeder lines are one of the most often used types of flexible transit services connecting a service area to a major transit network through a transfer point. They often switch operations between a demand responsive and a fixed-route policy. In designing and running such systems, the identification of the condition justifying the operating switch is often hard to properly evaluate. In this paper, we propose an analytical model and solution of the problem to assist decision makers and operators in their choice. By employing continuous approximations, we derive handy but powerful closed-form expressions to estimate the critical demand densities, representing the switching point between the competing operating policies. Based on the results of one-vehicle and two-vehicle operations for various scenarios, in comparison to values generated from simulation, we verify the validity of our analytical modeling approach.     

Toward regional transportation governance: a case study of Greater Vancouver

This paper discusses the evolving institutional structure and governance of transportation planning, policy development and transit delivery within one major North American city-region, the Greater Vancouver area. Various methods of transportation governance are explored from complete independence to full regional integration. The move away from a direct provincial role in transportation management to a greater regional transit authority is discussed and critiqued. This revised version was published online in June 2006 with corrections to the Cover Date.     

Analysis of Metropolitan Highway Capacity and the growth in vehicle miles of travel

A number of recent studies have examined the hypothesis of induced travel in an attempt to quantify the phenomenon (Hansen & Huang 1997; Noland, forthcoming). No study has yet attempted to adjust for potential simultaneity bias in the results. This study addresses this issue by the use of an instrumental variable (two stage least squares) approach. Metropolitan level data compiled by the Texas Transportation Institute for their annual congestion report is used in the analysis and urbanized land area is used as an instrument for lane miles of capacity. While this is not an ideal instrument, results still suggest a strong causal relationship but probably that most previous work has had an upward bias in the coefficient estimates. The effect of lane mile additions on VMT growth is forecast and found to account for about 15% of annual VMT growth with substantial variation between metropolitan areas. This effect appears to be closely correlated with percent growth in lane miles, suggesting that rapidly growing areas can attribute a greater share of their VMT growth to growth in lane miles.