18 research outputs found

    Performance Measures to Assess Resiliency and Efficiency of Transit Systems

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    Transit agencies are interested in assessing the short-, mid-, and long-term performance of infrastructure with the objective of enhancing resiliency and efficiency. This report addresses three distinct aspects of New Jersey’s Transit System: 1) resiliency of bridge infrastructure, 2) resiliency of public transit systems, and 3) efficiency of transit systems with an emphasis on paratransit service. This project proposed a conceptual framework to assess the performance and resiliency for bridge structures in a transit network before and after disasters utilizing structural health monitoring (SHM), finite element (FE) modeling and remote sensing using Interferometric Synthetic Aperture Radar (InSAR). The public transit systems in NY/NJ were analyzed based on their vulnerability, resiliency, and efficiency in recovery following a major natural disaster

    Implications of technological changes in vehicle routing interfaces for planners' constraint processing

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    International audienceThis study sought to assess the consequences of technological changes in vehicle routing interfaces for planners' constraint processing during route selection. We began by developing a model of domain constraints for the generic vehicle routing problem, in order to characterize planners' constraint processing and assess the visibility of constraints on different routing interfaces. An experiment featuring vehicle routing problems was then designed to test interfaces reflecting technological changes, including automation leading to simplified interfaces and the display of multiple routes computed by algorithms. Twelve participants who had worked for a small transport company for nine months were exposed to all these interfaces. Mental workload, performance and decision-making times were measured. Results revealed that automation decreases mental workload and decision times, attributable to the abridged (vs. unabridged) display of constraints on the interface. Results also showed that the perceptual (vs. analytical) display of routes greatly decreases decision times and enhances performances

    Compendium of Student Papers: Transportation Scholars Conference, Iowa State University, November 20, 1998

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    Traffic data collection techniques have became more advanced. New data collection technologies enable researchers to conduct their studies with a higher degree of precession and in more detail. One of the recently developed technologies is video vehicle detection. These systems are applied throughout the United States for providing signal timing at intersections, reducing the amount of travel time delay for motorists. Also, this technology has been effective in the lab for analyzing traffic data. One video detection system that is widely used is the Econolite Autoscope 2003. In this study, the Econolite Autoscope 2003 was used as the video vehicle detection system. This report provides guidance on how to properly setup a study site, and highlight<; some of the important features of video vehicle detection systems in the lab. The objective of this report was to provide instructional information on how to prepare a study site so that a video vehicle detection system can accurately collect data. The suggestions made within this report can be adapted for other types of video vehicle detection systems

    Computer Controlled Urban Transportation: A Survey of Concepts, Methods, and International Experiences

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    This book is concerned with the present and future traffic problems in the developing and developed world. It examines possible solutions to those problems based on technological innovations and implementing large-scale computerized traffic and transportation control systems. It discusses the basic concepts and methods for control and automation that have been proposed, developed, and implemented, and experience from real applications of these in different cities and nations

    Full Issue 9(4)

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    Full Issue 3(1)

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    The Multi-Agent Transport Simulation MATSim

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    "The MATSim (Multi-Agent Transport Simulation) software project was started around 2006 with the goal of generating traffic and congestion patterns by following individual synthetic travelers through their daily or weekly activity programme. It has since then evolved from a collection of stand-alone C++ programs to an integrated Java-based framework which is publicly hosted, open-source available, automatically regression tested. It is currently used by about 40 groups throughout the world. This book takes stock of the current status. The first part of the book gives an introduction to the most important concepts, with the intention of enabling a potential user to set up and run basic simulations.The second part of the book describes how the basic functionality can be extended, for example by adding schedule-based public transit, electric or autonomous cars, paratransit, or within-day replanning. For each extension, the text provides pointers to the additional documentation and to the code base. It is also discussed how people with appropriate Java programming skills can write their own extensions, and plug them into the MATSim core. The project has started from the basic idea that traffic is a consequence of human behavior, and thus humans and their behavior should be the starting point of all modelling, and with the intuition that when simulations with 100 million particles are possible in computational physics, then behavior-oriented simulations with 10 million travelers should be possible in travel behavior research. The initial implementations thus combined concepts from computational physics and complex adaptive systems with concepts from travel behavior research. The third part of the book looks at theoretical concepts that are able to describe important aspects of the simulation system; for example, under certain conditions the code becomes a Monte Carlo engine sampling from a discrete choice model. Another important aspect is the interpretation of the MATSim score as utility in the microeconomic sense, opening up a connection to benefit cost analysis. Finally, the book collects use cases as they have been undertaken with MATSim. All current users of MATSim were invited to submit their work, and many followed with sometimes crisp and short and sometimes longer contributions, always with pointers to additional references. We hope that the book will become an invitation to explore, to build and to extend agent-based modeling of travel behavior from the stable and well tested core of MATSim documented here.

    Coordinated Transit Response Planning and Operations Support Tools for Mitigating Impacts of All-Hazard Emergency Events

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    This report summarizes current computer simulation capabilities and the availability of near-real-time data sources allowing for a novel approach of analyzing and determining optimized responses during disruptions of complex multi-agency transit system. The authors integrated a number of technologies and data sources to detect disruptive transit system performance issues, analyze the impact on overall system-wide performance, and statistically apply the likely traveler choices and responses. The analysis of unaffected transit resources and the provision of temporary resources are then analyzed and optimized to minimize overall impact of the initiating event

    Mobile Robots Navigation

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    Mobile robots navigation includes different interrelated activities: (i) perception, as obtaining and interpreting sensory information; (ii) exploration, as the strategy that guides the robot to select the next direction to go; (iii) mapping, involving the construction of a spatial representation by using the sensory information perceived; (iv) localization, as the strategy to estimate the robot position within the spatial map; (v) path planning, as the strategy to find a path towards a goal location being optimal or not; and (vi) path execution, where motor actions are determined and adapted to environmental changes. The book addresses those activities by integrating results from the research work of several authors all over the world. Research cases are documented in 32 chapters organized within 7 categories next described
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