| It is necessary and essential to coordinate Urban Traffic Control System withUrban Traffic Guidance System, which will integrate traffic facilities and thusbuilding both intellignent and economical transportation system.In this paper, the operation mechanisms of traffic guidance system and trafficcontrol system are thoroughly analyzed respectively, then a state of the art review ofcoordination between UTCS and UTFGS in domestic and foreign countries aresynthesized in coordination pattern and coordination algorithm, which provideadvice and suggestion for the following research. In the next, a model based ondynamic spatial speed is discussed to select appropriate coordination opportunityand thus offering the theoretical foundation for when to implement coordination.Considering traffic information is the base for coordination, so the paper studied theinformation sharing of traffic control system and traffic guidance system to realizean economical transportation system. More importantly, A double-objective modelfor traffic flow guidance coordinated with signal control is presented in this paper,aiming at dispelling congestion at first level and minimizing total travel time of thenetwork secondly. In the last, taking into the current traffic management actualitiesof our country, based on existing traffic control facility and implement technology,a real-time offset optimization algorithm is put forward based on travel time and acoordination management stategy of emergency vehicles is intrduced.Information sharing is the foundation of coordination between traffic controlsystem and traffic guidance system. After introducing the data collection method ofthe two systems, coordination information platform architecture is configured andthe main modules are analyzed. Then, VISSIM is used to simulate informationcoordination, in the example, the influence of intersection delay against route traveltime is calculated, the more significant thing is that the relationship between traveltime and traffic volume as well as occupation is investigated, and the simple linearregression model is set up, which will offere theoretical foundation for coordinationof the two system in data collection and dissemination.In this paper, the problem when should cooperate the two systems is exploredin detail and the concept of cooperation opportunity is put forward. After analyzingthe changing regularities of traffic parameters under different conditions, averagespatial speed is selected to determine the optimal cooperation opportunity. Moreimportantly, an improved dynamic speed model is presented innovatively and thejudging process is discussed. Finally, In order to test the algorithm, a simulationexperiment is carried out with VISSIM software, the results from simulationsuggested that the improved dynamic speed model is very effective in searching forcooperation opportunity.A double-objective model for traffic flow guidance coordinated with signalcontrol is presented in this paper, aiming at dispelling congestion at first level andminimizing total travel time of the network secondly. To avoid rigid subject termsand make the model easily solved, the index of congestion measurement isintroduced, the method of short step signal timing adjustment and test optimizationis put forward, traffic flow is suggested to upload or download at links while signalcontrol is optimized at intersections until an efficiency and optimal travel operationis achieved. A simulation road network is set up, the quasi algorithm for thecoordination model is tested and the results are got satisfactorily, in whichcongestion is dispelled after 3 coordination intervals and the fourth and fifthcoordination made total travel time less than former.From the point of coordination of traffic control system and traffic guidancesystem, travel time collected in the guidance system is used to optimize signaltiming parameters such as offset, thus improving the adaptivity, flexibility andvalidity of the signal control system greatly. In the paper, the algorithm for offsetoptimization is emphasized on the basis of travel time especially, the relationshipbetween travel time and offset is discussed. By setting up an arterial containedthree intersection with VISSIM, the results of the simulation indicate that the traveltime of arterial is saved about 12.9% at most and the delay decreased to 51.3% withthe offset optimization.Aiming at ITS technologies application in traffic incident management, acoordination management strategy is put forward, in which hierachical judgementand coordination operation is presented and realize the cooperation of trafficcontrol system and traffic guidance system from two levels. After an extensiveliterature review of Automatic Incident Detection (AID) on abroad and domestic,the paper analyzes both the characteristics of traffic roadway and the criticalrequirements of AID system, and addresses traffic detectors layout as well as theiroptimization density for AID data collection. Further more, the paper presents anAID algorithm based on Fisher discriminant with selecting four traffic parametersthat most sensitive to incident occurrence. In the end, the AID model is tested withhistorical data collected from Shenzhen, the evaluation results show that the AIDmodel based on Fisher discriminant has perfect performance such as fast detectionand high detection rate. In the paper, importance is put on signal timing priority ofemergent vehicle. Detailes about signal changing for right through, left and rightturn vehicles under two phase are studied.
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