02188nas a2200217   4500008004100000245008400041210006900125260000900194300001400203490000700217520149000224653002101714653002301735653001601758653002801774100001301802700001301815700001401828700001101842856011701853       2013                        eng d00aException detection for web service composition using improved bayesian network0 aException detection for web service composition using improved b  c2013  a108 - 1140 v113 aNew application systems generated by composition of web services dynamically have become a development trend in network environment. However, since a variety of external services are invoked with different quality of service during processing, the problem of how to keep the execution stable must be addressed in order to improve the reliability and availability of the combination of services. In this paper, an approach of exception detection is presented for web service composition by improved Bayesian network. Firstly, the topological structure of Bayesian network is established, where the causal relationships between underlying web services are mapped to Bayesian network in service combination process. The conventional Bayesian network algorithm is improved to satisfy the demand of better conversion from nodes in web service composition to nodes in Bayesian network. Secondly, the parameter setting in Bayesian network is explored for determining the prior probability of service nodes and the conditional probability of service output node. Thirdly, the algorithm of the improved exception detection model is introduced, with the aim of locating the web services that cause exceptions in the execution of composite services. Lastly, a case study is given and the results analysis is also conducted. The results show that the presented approach not only considers the uncertainty during exception detection, but also can identify the exception web services in the process.10aBayesian network10aException handling10aWeb service10aWeb service composition1 aChen, Y.1 aYing, S.1 aZhang, L.1 aWu, J.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-84879099166&partnerID=40&md5=0973327f022946c84a165872a228552401854nas a2200205   4500008004100000245008300041210006900124260000900193300001400202490000600216520115100222653002401373653002901397653002301426653002801449653001301477100001801490700002301508856011701531       2010                        eng d00aQos-aware selection of web service compositions using Harmony Search algorithm0 aQosaware selection of web service compositions using Harmony Sea  c2010  a160 - 1660 v83 aExtensive use of web services has lead to introduce web service compositions to execute business workfiows. Since several function equivalent services, provided by different service providers, may be available in the Web, the problem of selection of web service compositions arises. QoS aware selection means considering the quality of the service composition in choosing constituent services. So a method is needed for computing the quality of a composition and determining the composition with the (almost) best quality. The resulting composite has optimal quality and satisfies user's quality constraints. In this paper, the problem of QoS aware selection of web service composition is modeled as an optimization problem. Then a variation of Harmony Search algorithm is used to find a near optimal composition. Harmony Search is a recently developed optimization algorithm that mimics the improvisation process. The proposed method based on Harmony Search has been applied to a large variety of composition schemas, generated by a simulation software, and the results show that the proposed method works faster, compared with other approaches.10aGlobal optimization10aHarmony Search algorithm10aQuality-of-service10aWeb service composition10aWorkflow1 aJafarpour, N.1 aKhayyambashi, M.R.  uhttp://www.scopus.com/inward/record.url?eid=2-s2.0-79960212292&partnerID=40&md5=8b2aa95f15cbf2d77baea346d4870d04