The Study Of Improved Urban Public Transport Inquiry Algorithms

Urban public transport inquiry system for provides the optimizated and quick information service to facilitate passengers'travel in a large extent though a reasonable guide. And at same time, this kind of system can reduce the unnecessary traffic flow and improve operation efficency of entire public transportation network and the level of urban information services. This paper researched the urban public transport algorithm in a deep-going way and mainly did the followings:First, several existing public transport inquiry algorithms are analyzed in the paper. Wielding comparison, their superiority-inferiority is summarized. Then the research thoughts of this paper are determined and the key problems that need to be solved in this work are also concluded. On this basis, after the main features of domestic public transport network and passengers'travel psychology are researched. A multi-objective programming mathematical model of urban public transport inquiry is established, which aims at the optimization of transfer times, time and economy.Next, according to intricate, inconsistent round-trip urban public transport routes, and other characteristics of routes, a kind of storage policy based on dual adjacency list is proposed to avoid problems that traditional methods of storage are not conducive to search public transport routes. On this basis, according to above mathematical model, a kind of level search public transport routes inquiry algorithm based on routes priority is proposed, which leads into preference coefficient and considers transfer times, time, economy and other optimization targets. The analysis and simulation show that the new algorithm has high precision and good practicality, and it can meet the actual needs of different passengers.Then, aiming at the low operation speed of portable devices, on the ground of above mathematical model, a kind of rapid algorithm about public transport inquiry is also proposed. In the algorithm, transfer times are regarded as optimization targets, while time and economy cost are weakened as binding conditions. And to improve response speed, invalid transfer operations are also inhibited. The analysis and simulation showed that, compared with the existing algorithms, the new algorithm can guarantee the quality of inquiry results, and it also has shorter response time at the same time. So it is a more suitable algorithm for portable devices.Finally, in the J2ME Wireless Toolkit environment, a public transport inquiry prototype system is realized, which has certain versatility and is suitable for researching routes between two arbitrary places in any city. And the test results show that the algorithm we have proposed can meet different passengers'needs, and it also has better versatility and good performance.