Environment

The objective of this study is to address the communication system design issues of Intelligent Vehicle Highway Systems (IVHS). The focus of Phase I of this research is the design for California Advanced Driver Information Systems (CADIS). The emphasis is on the architecture and topology aspects of the physical link and access layers connecting the moving layers with the fixed infrastructure. The work is divided into the following categories: Automatic Vehicle Identification (AVI), IVHS communications survey and functional requirements, modeling of IVHS fading channels, multiple-access...

This report documents findings from analysis of traffic collision data from sites that display high collision rates only under wet pavement conditions. These sites were selected using Caltrans safety engineers’ field reports, Wet Table C “investigation required” locations, and a new approach called Continuous Risk Profile (CRP).The geometric features at the sites were studied via field visits and review of as-built plans. Rapid spatial changes (i.e., vertical and horizontal curve in short distance), narrower lane width, lack of median, and wider total freeway width were some of the notable...

This report describes a computer environment for rapidly prototyping user interfaces for advanced driver information systems (ADIS).

Electric vehicle (EV) emissions occur when a vehicle is charged and are based on the mix of power sources used during that period. The rapid growth of solar and wind energy has introduced a high degree of variability in the emissions of the grid for both diurnal and annual periodicities. Growth in solar energy has been particularly prominent in California. Using grid mix data spanning April 2018 to April 2023 from the California Independent System Operator (CAISO) and power source emission factors, we evaluate the grid mix at 5 min intervals and estimate the emission factors based on the...