PATH

This report investigates the performance of model-based estima-tion over multi-access networks and emphasizes on the estimationMSE (mean squared error) while using different channel access schemes:probabilistic (random access), deterministic (round-robin scheduling),and combined (grouped channel access). We propose a mathematicalframework for estimation over a simple multi-access MAC protocol,the slotted ALOHA network. Estimation MSE, its asymptotic be-havior and stability condition are derived for different channel accessmethods. Our quantitative discussion can provide guidelines to...

This report presents the results of its examination of the current state of the practice of traveler information data sharing with the public and private sectors. A review of the literature was initially performed followed by an analysis of responses to a survey instrument that was designed and administered to practitioners in the field, primarily representatives from public sector agencies, who are in the business of collecting traveler information data. Survey results have addressed the subjects of what data is shared, with whom it is shared, why it is shared, how it is institutionally...

In analogy to the flow of fluids, it is expected that the aggregate density and the velocity of vehicles in a section of a freeway adequately describe the traffic flow dynamics. The conservation of mass equation together with the aggregation of the vehicle following dynamics of controlled vehicles describes the evolution of the traffic density and the aggregate speed of a traffic flow. There are two kinds of stability associated with traffic flow problems - string stability (or car-following stability) and traffic flow stability. We make a clear distinction between traffic flow stability...

This report presents the findings of its investigation of institutional aspects of bus rapid transit (BRT) through both a macroscopic examination, a survey of members of the U.S. Bus Rapid Transit Consortium and several Canadian transit properties, and a more focused site-specific examination of three California BRT systems. The macroscopic examination resulted from a literature review, project team brainstorming meetings, and input from the Federal Transit Administration. Several dozen issues were identified and were grouped into nine categories that formed the basis of the survey:...