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Travel time estimation is of increasing importance to travelers and transportation professionals alike as congestion worsens in major urban areas. In fact, the reliability of travel time estimates on a given corridor may be more important for travelers, shippers, and transport managers than the travel time itself. This paper examines the uses of measured(More)
7 Abstract 8 In this paper a new method for real time estimation of vehicular flows and densities on motorways is proposed. This 9 method is based on fusing traffic counts with mobile phone counts. The procedure used for the estimation of traffic flow 10 parameters is based on the hypothesis that ''instrumented'' vehicles can be counted on specific motorway(More)
Details of traffic evolution were studied upstream and downstream of a freeway bottleneck located near a busy on-ramp. It is shown that on certain days the bottleneck became active upon dissipation of a queue emanating from somewhere further downstream. On such occasions, the bottleneck occurred at a fixed location, approximately one kilometer downstream of(More)
To address increasing traffic congestion and its associated consequences, traffic managers are turning to intelligent transportation management. The <i>latte</i> project is extending data stream technology to handle queries that combine live streams with large data archives, motivated by needs in the Intelligent Transportation Systems (ITS) domain. In(More)
Transit travel time and operating speed influence service attractiveness, operating cost, and system efficiency. The objective of this paper is to estimate the values of parameters that affect the total travel time for a particular bus route in Portland, Oregon. The Metropolitan Transportation District of Oregon ͑TriMet͒ provides transit service in the(More)
A System-Wide Adaptive Ramp Metering (SWARM) system is being implemented in the Portland metropolitan area, replacing the previous pre-timed ramp-metering system. SWARM has been deployed on six major corridors and operates during the morning and afternoon peak hours. This study entails a ―before‖ and ―after‖ evaluation of the benefit of the new SWARM system(More)
Probe vehicles with Global Positioning Systems (GPS) can provide accurate positions that enable spatial-average speed estimation. However, some probe vehicles cannot provide accurate positions but can provide location-specific information on when and where they are located at the segment or cell level. These topological position (TP) data with segment- or(More)