Publications in Semantic Web

Articles in Refereed Journals:

1. Groenmo, R., Jaeger, M.C.. Model-driven semantic Web service composition. Software Engineering Conference, 2005. APSEC '05. 12th Asia-Pacific, To Appear, December 2005.
   Abstract: As the number of available Web services increases there is a growing demand to realise complex business processes by combining and reusing available Web services. The reuse and combination of services results in a composition of Web services that may also involve services provided in the Internet. With semantically described Web services, an automated matchmaking of capabilities can help identify suitable services. To address the need for semantically defined Web services, OWL-S and WSML have been proposed as competing semantic Web service languages. We show how the proposed semantic Web service languages can be utilized within a model-driven methodology for building composite Web services. In addition we combine the semantic-based discovery with the support for processing QoS requirements to apply a ranking or a selection of the candidates. The methodology describes a process which guides the developer through four phases, starting with the initial modelling, and ending with a new composite service that can be deployed and published to be consumed by other users.

Articles in Refereed Conferences:

1. Kyriakos Kritikos, Dimitris Plexousakis. OWL-Q for Semantic QoS-based Web Service Description and Discovery. First International Joint Workshop on Service Matchmaking and Resource Retrieval in the Semantic Web, November 2007.
   Abstract: Semantic Web Services are emerging for their promise to produce a more accurate and precise Web Service discovery process. However, most of research approaches focus only on the functional part of semantic Web Service description. The above fact along with the proliferation of Web Services is highly probable to lead to a situation where Web Service registries will return many functionally-equivalent Web Service advertisements for each user request. This problem can be solved with the semantic description of QoS for Web Services. QoS is a set of non-functional properties encompassing performance and network- related characteristics of resources. So it can be used for distinguishing between functionally-equivalent Web Services. Current research approaches for QoS-based Web Service description are either syntactic or poor or non-extensible. To solve this problem, we have developed a rich and extensible ontological specification called OWL-Q for semantic QoS-based Web Service description. We analyze all OWL-Q parts and reason that rules should be added in order to support property inferencing and constraint enforcement. Finally, we line out our under-development semantic framework for QoS-based Web Service description and discovery.

2. Ester Giallonardo, Eugenio Zimeo. More Semantics in QoS Matching. SOCA, pages 163-171, 2007.
   Abstract: The evolution of the Web towards a global computing environment is promoting new research efforts aimed at the formal characterization of Web Services QoS. Reasoning on QoS is a key to improve matching process during the discovery of desired services and a step towards the transformation of applications in collections of loosely coupled services virtually connected by semantic similarities. The paper presents the on QoS ontology, an openly available OWL ontology for QoS, and evaluates it in a QoS-aware matching environment. The ontology can be used to express functions of QoS metrics useful to improve the recall tied to the matching of a template request with target Web Services. To this end, the ontology introduces the concept of derivation in the matching process. This gives the possibility of matching a QoS template with published Web Services by deriving different QoS parameters when a one-to-one matching fails. The proposed matching algorithm utilizes a reasoner that exploits the ontology to avoid apparent mismatches. An experimental evaluation shows that exploiting QoS knowledge significantly improves matching recall without deteriorating precision.

3. Srini Narayanan, Sheila A. McIlraith. Simulation, verification and automated composition of web services. WWW '02: Proceedings of the 11th international conference on World Wide Web, pages 77-88, ACM, 2002.
   Abstract: Web services - Web-accessible programs and devices - are a key application area for the Semantic Web. With the proliferation of Web services and the evolution towards the Semantic Web comes the opportunity to automate various Web services tasks. Our objective is to enable markup and automated reasoning technology to describe, simulate, compose, test, and verify compositions of Web services. We take as our starting point the DAML-S DAML+OIL ontology for describing the capabilities of Web services. We define the semantics for a relevant subset of DAML-S in terms of a first-order logical language. With the semantics in hand, we encode our service descriptions in a Petri Net formalism and provide decision procedures for Web service simulation, verification and composition. We also provide an analysis of the complexity of these tasks under different restrictions to the DAML-S composite services we can describe. Finally, we present an implementation of our analysis techniques. This implementation takes as input a DAML-S description of a Web service, automatically generates a Petri Net and performs the desired analysis. Such a tool has broad applicability both as a back end to existing manual Web service composition tools, and as a stand-alone tool for Web service developers.