This paper presents a new procedure for signal coordination along oversaturated arterials. It is based o nqueue management and efficient green time utilization concepts. The main idea is to dynamically manage queue formation and idssipation on system links such that traffic flow is maximized and reasonable through bands are attained. This is achieved by eficiently using green time, preventing intersection blockage, accountign for the non-steady state conditions and providing dynamic, time-dependent control. The problem is formulated as a throughput maximizatio nsubject to state and control variable.s a solution usign Genetic Algorithms (GAs) is then presented. reults show that offsets and green times were dynamically changed as a function of demand and queue lengths. With long queues present, the algorithm utilized appropriate (negative) offsets to reduce or eliminate these queues, and then gradually mvoed to positive offsets to provide forward green bands, hence normal traffic progression. The algorithm has good potential for on-line real time implementation in an intelligent transportation systems (ITS) environment.
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