The Clean Air Act Amendments of 1990 have created a need for accurate and reliable estimates of peak-period travel and the speeds at which vehicles operate during that time period. State transportation agencies are faced with the problem of generating the volume and speed data needed to develop mobile source emissions inventories. This problem is compounded by the absence of current time-of-day travel characteristics. Although some of the software vendors that developed programs for the four-step travel demand forecasting process are also developing postprocessors that prepare the 24-hr model output for input to the emissions calculations models, a critical need to be able to respond to clean air agency needs required the development of an immediate response mechanism. The focus is on the application of a travel demand model and an annual traffic count program as the prime ingredients for a process that can be used to convert the 24-hr travel demand model output to peak-hour estimates of travel. The approach is a practical, how-to procedure that enables the user to estimate volumes and speeds for any hour of the day and for any day of the year, with the ultimate objective of preparing a base year inventory of mobile on-road emissions. Current data sources are evaluated and applied in the process.


  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 30-37
  • Monograph Title: Travel demand modeling and network assignment models
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00670481
  • Record Type: Publication
  • ISBN: 0309055245
  • Files: TRIS, TRB
  • Created Date: Dec 23 1994 12:00AM