Grand Challenges in Modeling and Simulating Urban Transportation Systems

est ce fits. Abstract Congestion in surface transportation systems reached unprecedented levels, and now costs ten billions of dollars each year in productivity and ext fuel costs in the U.S. alone. Accidents kill tens thousands of individuals each year, and polluti from vehicle emissions degrades the quality of life every citizen. Given the cost and danger experimenting with operational systems a limitations of purely analytic techniques, effectiv modeling and simulation (M&S) tools are essential solving these problems. However, existing simulati tools are far from adequate, and typically focus only a particular aspect of the problem. This pap surveys the use of M&S in modeling surfac transportation systems. A grand challenge proposed to realize robust, accurate models transportation infrastructures and its users for la metropolitan areas over time scales ranging fr minutes to years. M&S tools are needed to pred the impact of both planned and unplanned change well as the introduction of new technologies, prioritize infrastructure investments, to manage system under unexpected operating conditions traffic loads, to develop emergency and securi related contingency plans, and to test the impact various governmental policies on regional econom viability. Meeting this challenge will require holistic approach that includes accurate models individual travelers and businesses, as well as transportation infrastructure itself.