摘要: |
Transportation agencies have traditionally focused on building physical facilities such as highways, bridges, and transit systems. However, it has become increasingly difficult to build new highways or expand existing ones due to environmental impacts and the high cost of construction. Further, it has been estimated that roughly half of all congestion experienced by U.S. highway travelers is due to nonrecurring events or disruptions, such as traffic incidents, inclement weather, work zones, and special events (e.g., sporting venues, evacuations). As a result, transportation operations has emerged as a highly cost-effective solution to the national congestion problem. Its focus is to manage the flow of traffic efficiently on the existing highway system, in other words, to get the most out what we already have. In concept, this is similar to how the electric grid is managed operators constantly monitor the system looking for disruptions or areas where demand is high and take appropriate actions to address the problems. |