Data

We propose a methodology for identifying queue spillovers in city street networks with signalized intersections using data from conventional surveillance systems, such as counts and occupancy from loop detectors. The key idea of the proposed methodology is that when spillovers from a downstream link block vehicle departures from the upstream signal line, queues discharge at rates smaller than the saturation flow. The application of the methodology on an arterial site and the comparison with field data show that it consistently identifies spillovers in urban networks with signal-controlled...

The I-880 field experiment has produced one of the largest data bases on incidents and freeway traffic-flow characteristics ever compiled. Field data on incidents were collected through observations of probe-vehicle drivers before and after the implementation of freeway service patrols (FSPs) over a freeway section. Supplementary information was collected from the California Highway Patrol's computer-aided dispatch system, FSPs, and tow-truck company logs. The incident patterns are described and the major factors affecting incident frequency and duration are identified. FSPs significantly...

The past few years have seen a rapid evolution in the sophistication of traffic microsimulation models and a consequent major expansion of their use in transportation engineering and planning practice. Researchers and practitioners have employed an extensive array of approaches to calibrate these models and have selected a wide range of parameters to calibrate and a broad range of acceptance criteria. A methodical, top-down approach to model calibration is outlined; it focuses the initial effort on a few key parameters that have the greatest impact on model performance and then proceeds to...

This report presents the findings of a comprehensive evaluation of the freeway service patrol (FSP) program on specific freeway section in the San Francisco Bay Area. The study methodology consisted of determining the savings in incident delay and other performance measures "before" and " after" the implementation of FSP based on field data and improved analysis procedures. Data were collected during the peak periods on a mile section of the I-880 freeway in the City of Hayward, Alameda County. Software was developed to process the field data and create a computerized database. Benefits of...