Real Time Path Selection For Unexpected Congestion Nder Multiple Attributes Of Road Sections

Urban traffic congestion is becoming more and more serious,which brings huge losses to travelers both in time and the economic.Domestic and foreign scholars have achieved a lot of achievements in the research on the problem of real-time path selection for sudden congestion.However,the previous studies generally only take the single attribute of road section as the basis for decision making,and in practice,many attributes,such as road condition level,accident rate and so on,would also affect the path choosing of travelers.In this paper,we proposed a real-time path selection problem of sudden congestion under multi-attribute conditions.Firstly,the method of multi-attribute decision making is used to define path synthesis attribute value,and the goal is to minimize the path comprehensive attribute value as far as possible.By using the techniques and means of online problem and competition strategy,the online strategy of sudden congestion real-time path selection problem is designed under multi-attribute condition,the competitive ratio of the strategy is proved,and the competitive performance of the strategy is analyzed.Finally,taking the local road network in Shanghai and Xi'an as an example,the paper verifies the implementation effect of the strategy;and provides the basis for travelers to choose the route and the road traffic guidance.The main innovative achievements are as follows.On-line path selection strategy design sudden blocking under multi-attributes of road sections can be recovered.Firstly,several attributes that affect the path choice of travelers are given,including the distance,the level of the road condition,the accident rate and so on.The method of multi-attribute decision is used to define the comprehensive attribute value of the road section.The section with the highest comprehensive attribute value of any path is called the critical section,and the comprehensive attribute value of the critical road is defined as the comprehensive attribute value of the path.In the paper,by means of online problem and competition strategy,under the circumstances of sudden congestion occurring on critical and non-critical sections,and taking the goal of minimize the path comprehensive attribute value as far as possible,the waiting strategy and the greedy strategy for the real-time path selection problem are designed.It has been proved that the competitive ratio of waiting strategy and greedy strategy is1+? andh?.Then analyze the implementation effect of the strategy.Finally,taking the local road network in Shanghai as an example,the paper has verified the effect of waiting strategy and greedy strategy,and provided a reference for traveler route selection and road traffic guidance.On-line path selection strategy design for sudden blocking under multiple attributes of road sections can not be recovered.Based on the definition of the attribute value of path synthesis,by means of online problem and competition strategy.under the circumstances of bypass path passed through the critical section of the minimum path with comprehensive attribute value and bypass path didn't pass through the critical section of the minimum path with comprehensive attribute value,and taking the goal of minimize the path comprehensive attribute value as far as possible,The full bypass strategy and roundabout strategy for the problem of unrecoverable real time path selection of road sections with multiple attributes are designed.It is proved that the competition ratio of the full bypass strategy and roundabout strategy is ?? and ?*,Then analyze the implementation effect of the strategy.Finally,taking the local road network in Xi'an as an example,the paper has verified the effect of the full bypass strategy and the roundabout strategy,and provided a reference for traveler route selection and road traffic guidance.