Abstract: For the public transport query system，the passengers sometimes take into consideration multiple factors such as transfers，distance，expenses，type of lines etc.Therefore a travel route query model needs to support multiple level goals.Therefore based on the direct graph with weights，a new query model which satisfies multiple query requirements by changing weights is defined，and the strategy of assigning weights is discussed according to travel route query that satisfies three level requirements including the least transfer，prior ride condition and the minimal stops.Experiment show that the model proposed is effective，available as well as good flexibility.

Key words: public transport, transfer, direct graph, shortest path

摘要： 在公交查询系统中，出行者往往考虑到换乘次数、出行距离、乘车费用、线路类型等诸多因素。因此出行路径查询模型要考虑到多重目标。为此基于带权有向图定义了一个新的查询模型，该模型能够通过调整权值来满足多重查询目标，并以满足最小换乘次数、优先乘车条件和最少途经站点数三重目标的出行路径查询为例，讨论了权值设定策略。实验表明，提出的模型有效、实用，具有很好的灵活性。

关键词: 公共交通, 换乘, 有向图, 最短路径