关键词: Web服务, 马尔可夫决策过程, 情景演算

Abstract: To deal with uncertainty of business logic and Quality of Service (QoS) in Web services, Markov Decision Processes (MDP) and high level logic programming language DT-Golog were used to solve uncertain planning problem of Web Services Composition (WSC). Web service invocation was regarded as a stochastic action, and MDP formal model was used to describe WSC. Moreover, situation calculus and its high level logic programming language DT-Golog, which was augmented with MDP, were used to give the logic representation of WSC, and the optimal policy of WSC was obtained by planning based on MDP. Finally, programming and planning combination advantages of DT-Golog to solve WSC were also illustrated.

Key words: Web services, Markov decision process, situation calculus