Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability desc...Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.展开更多
服务发现是面向服务的网络软件开发过程的关键阶段,同时也是影响服务组合效率的关键因素.针对当前服务发现自动化程度低下、准确性不高的现状,从两个方面提高服务组合效率:首先,提出一种自动组合服务发现模式,支持流程粒度的组合服务发...服务发现是面向服务的网络软件开发过程的关键阶段,同时也是影响服务组合效率的关键因素.针对当前服务发现自动化程度低下、准确性不高的现状,从两个方面提高服务组合效率:首先,提出一种自动组合服务发现模式,支持流程粒度的组合服务发现及复用;其次,在发现过程中设计了一种量化的相似性评估算法,综合考虑组合流程的静态结构与动态行为特征,以提高服务发现的准确率;最后,结合以上两方面形成一个基于流程相似性的自动服务发现框架(automatic service discovery framework based on business process similarity,简称AutoDisc).利用真实数据完成的评估实验结果表明,AutoDisc的准确性优于单纯考虑结构或行为的发现方法,在所给出的应用案例中,使服务组合效率提高75.5%,具有较好的可扩展性.展开更多
In the research of service composition,it demands efficient algorithms that not only retrieve correct service compositions automatically from thousands of services but also satisfy the quality requirements of differen...In the research of service composition,it demands efficient algorithms that not only retrieve correct service compositions automatically from thousands of services but also satisfy the quality requirements of different service users.However,most approaches treat these two aspects as two separate problems,automatic service composition and service selection.Although the latest researches realize the restriction of this separate view and some specific methods are proposed,they still suffer from serious limitations in scalability and accuracy when addressing both requirements simultaneously.In order to cope with these limitations and efficiently solve the combined problem which is known as QoS-aware or QoS-driven automatic service composition problem,we propose a new graph search problem,single-source optimal directed acyclic graphs （DAGs）,for the first time.This novel single-source optimal DAGs （SSOD） problem is similar to,but more general than the classical single-source shortest paths （SSSP） problem.In this paper,a new graph model of SSOD problem is proposed and a Sim-Dijkstra algorithm is presented to address the SSOD problem with the time complexity of O（n log n ＋ m） （n and m are the number of nodes and edges in the graph respectively）,and the proofs of its soundness.It is also directly applied to solve the QoS-aware automatic service composition problem,and a service composition tool named QSynth is implemented.Evaluations show that Sim-Dijkstra algorithm achieves superior scalability and efficiency with respect to a large variety of composition scenarios,even more efficient than our worklist algorithm that won the performance championship of Web Services Challenge 2009.展开更多
By analyzing of the existing Web services,an ontology based on OWL is presented,which has rich semantic information,and the service description language OWL-S based on OWL is put forward. OWL-S through IOPE can descri...By analyzing of the existing Web services,an ontology based on OWL is presented,which has rich semantic information,and the service description language OWL-S based on OWL is put forward. OWL-S through IOPE can describe services,can also combine the service,but the method of combination service is not automatic. So a method is presented by using Situation Calculus for automatic service composition based on the OWL-S model. Finally through the example analysis,the method of automatic service combination was validated.展开更多
Almost all current automatic service composition （ASC） algorithms consider only single nonfunctional requirements, namely quality of service （QoS）, which cannot satisfy the real application. This paper proposes M...Almost all current automatic service composition （ASC） algorithms consider only single nonfunctional requirements, namely quality of service （QoS）, which cannot satisfy the real application. This paper proposes MAT （multi-QoS aware top-K ASC） algorithm to realize the high-efficiency exploring and rank- ing of composition scheme by synthesizing more nonfunctional goals. MAT algorithm explores composition schemes by the sky- line technique based on tape model and ranks these schemes by a modified binary tree. Using Web service challenge （WSC） 2009 dataset, we verify the performance of MAT algorithm and the experimental result is even close to the current fastest ASC algo- rithm considering only single QoS.展开更多
基金This work was partly supported by the National Natural Science Foundation of China （Grant Nos. 60233010 and 60496324） the National Key Research and Development Program of China （Grant No. 2002CB312004） the Knowledge Innovation Program of the Chinese Academy of Sciences and MADIS of the Chinese Academy of Sciences.
文摘Automatic discovery and composition of Web services is an important research area in Web service technology, in which the specification of Web services is a key issue. This paper presents a Web service capability description framework based on the environment ontology. This framework depicts Web services capability in two aspects： the operable environment and the environment changes resulting from behaviors of the Web service. On the basis of the framework, a requirement-driven Web service composition model has been constructed. This paper brings forward the formalization of Web service interactions with π calculus. And an automatic mechanism converting conceptual capability description to the formal process expression has been built. This kind of formal specification assists in verifying whether the composite Web service model matches the requirement.
文摘服务发现是面向服务的网络软件开发过程的关键阶段,同时也是影响服务组合效率的关键因素.针对当前服务发现自动化程度低下、准确性不高的现状,从两个方面提高服务组合效率:首先,提出一种自动组合服务发现模式,支持流程粒度的组合服务发现及复用;其次,在发现过程中设计了一种量化的相似性评估算法,综合考虑组合流程的静态结构与动态行为特征,以提高服务发现的准确率;最后,结合以上两方面形成一个基于流程相似性的自动服务发现框架(automatic service discovery framework based on business process similarity,简称AutoDisc).利用真实数据完成的评估实验结果表明,AutoDisc的准确性优于单纯考虑结构或行为的发现方法,在所给出的应用案例中,使服务组合效率提高75.5%,具有较好的可扩展性.
基金Supported by the National Basic Research 973 Program of China under Grant No.2007CB-310805the National Natural Science Foundation of China under Grant No.61070027+2 种基金the Beijing Natural Science Foundation project under Grant No.4092043the Scienceand Technology Project of State Grid Information&Telecommunication Company Ltd.under Grant No.SGIT[2010]449the Planned Science and Technology Project of Guangdong Province,China under Grant No.2010B050100009
文摘In the research of service composition,it demands efficient algorithms that not only retrieve correct service compositions automatically from thousands of services but also satisfy the quality requirements of different service users.However,most approaches treat these two aspects as two separate problems,automatic service composition and service selection.Although the latest researches realize the restriction of this separate view and some specific methods are proposed,they still suffer from serious limitations in scalability and accuracy when addressing both requirements simultaneously.In order to cope with these limitations and efficiently solve the combined problem which is known as QoS-aware or QoS-driven automatic service composition problem,we propose a new graph search problem,single-source optimal directed acyclic graphs （DAGs）,for the first time.This novel single-source optimal DAGs （SSOD） problem is similar to,but more general than the classical single-source shortest paths （SSSP） problem.In this paper,a new graph model of SSOD problem is proposed and a Sim-Dijkstra algorithm is presented to address the SSOD problem with the time complexity of O（n log n ＋ m） （n and m are the number of nodes and edges in the graph respectively）,and the proofs of its soundness.It is also directly applied to solve the QoS-aware automatic service composition problem,and a service composition tool named QSynth is implemented.Evaluations show that Sim-Dijkstra algorithm achieves superior scalability and efficiency with respect to a large variety of composition scenarios,even more efficient than our worklist algorithm that won the performance championship of Web Services Challenge 2009.
文摘By analyzing of the existing Web services,an ontology based on OWL is presented,which has rich semantic information,and the service description language OWL-S based on OWL is put forward. OWL-S through IOPE can describe services,can also combine the service,but the method of combination service is not automatic. So a method is presented by using Situation Calculus for automatic service composition based on the OWL-S model. Finally through the example analysis,the method of automatic service combination was validated.
基金Supported by the National Natural Science Foundation of China(U1135005)the Dawn Plan Project of Wuhan(2013070104010036)
文摘Almost all current automatic service composition （ASC） algorithms consider only single nonfunctional requirements, namely quality of service （QoS）, which cannot satisfy the real application. This paper proposes MAT （multi-QoS aware top-K ASC） algorithm to realize the high-efficiency exploring and rank- ing of composition scheme by synthesizing more nonfunctional goals. MAT algorithm explores composition schemes by the sky- line technique based on tape model and ranks these schemes by a modified binary tree. Using Web service challenge （WSC） 2009 dataset, we verify the performance of MAT algorithm and the experimental result is even close to the current fastest ASC algo- rithm considering only single QoS.
