Data

A new version of a field-deployable real-time laser-based detection system has been developed using new techniques of electronics and optics. The laser-based non-intrusive detection system uses a laser line that is projected onto the ground as a probe. The reflected light is collected and focused into a photodiode array by an optical system. Vehicle presence is detected based on the absence of reflected laser light. By placing two identical laser/sensor pairs at a known distance apart, the speeds of both the front and rear of a vehicle are measured based on the times when each sensor is...

This report presents the findings of its investigation into intermodal passenger transfer facilities' operations and services in urban areas of California and the opportunities for how the application of intelligent transportation systems may enhance such operations and services. The project was based initially on a macroscopic assessment of intermodal passenger transfer facility operations and services primarily by means of a review of the literature followed by a three-tier analysis through site visits, institutional aspects, and user views and opinions. Institutional aspects were...

Health researchers have increasingly adopted the use of geographic information systems (GIS) for analyzing environments in which people live and how those environments affect health. One aspect of this research that is often overlooked is the quality and detail of the road data and whether or not it is appropriate for the scale of analysis. Many readily available road datasets, both public domain and commercial, contain positional errors or generalizations that may not be compatible with highly accurate geospatial locations. This study examined the accuracy, completeness, and currency of...

This report describes how current methods of estimating truck traffic volumes from existing fixed roadway sensors could be improved by using tracking data collected from commercial truck fleets and other connected technology sources (e.g., onboard GPS-enabled navigation systems and smartphones supplied by third-party vendors). Using Caltrans District 1 in Northern California as an example, the study first reviews existing fixed-location data collection capabilities and highlights gaps in the ability to monitor truck movements. It then reviews emerging data sources and analyzes the...