摘要: |
Understanding vehicle activity patterns both spatially and temporally is critical for building accurate mobile source emissions inventories. Vehicle activity has frequently been characterized using average speed and vehicle miles traveled (VMT), however advances in modeling of mobile sources have increased the resolution in vehicle activity necessary for using the new models to their full capabilities. Recently, two GPS (Global Positioning System)-based vehicle activity datasets have become available from several different research programs. In 2001, the California Department of Transportation (Caltrans) conducted their 2001 California Statewide Household Travel Survey Program, which contains GPS-based data sets from across the state. This data set is approximately 125 MB in size and represents about 272 households. This database was divided into two parts, one corresponding to Northern California trips and the other corresponding to Southern California trips. Further, the Southern California Association of Governments (SCAG) carried out a post-census travel survey in 2001, which contains a number of GPS-data logger datasets. This data set represents approximately 467 households. / NOTE: Final rept. / Supplementary Notes: Sponsored by California State Air Resources Board, Sacramento. Research Div. / Availability Note: Product reproduced from digital image. Order this product from NTIS by: phone at 1-800-553-NTIS (U.S. customers); (703)605-6000 (other countries); fax at (703)605-6900; and email at orders@ntis.gov. NTIS is located at 5285 Port Royal Road, Springfield, VA, 22161, USA. |