252 research outputs found
Improving Semantic Web Services Discovery Using SPARQL-Based Repository Filtering
Semantic Web Services discovery is commonly a heavyweight task, which has scalability issues when the number of
services or the ontology complexity increase, because most approaches are based on Description Logics reasoning. As
a higher number of services becomes available, there is a need for solutions that improve discovery performance. Our
proposal tackles this scalability problem by adding a preprocessing stage based on two SPARQL queries that filter service
repositories, discarding service descriptions that do not refer to any functionality or non-functional aspect requested by
the user before the actual discovery takes place. This approach fairly reduces the search space for discovery mechanisms,
consequently improving the overall performance of this task. Furthermore, this particular solution does not provide yet
another discovery mechanism, but it is easily applicable to any of the existing ones, as our prototype evaluation shows.
Moreover, proposed queries are automatically generated from service requests, transparently to the user. In order to
validate our proposal, this article showcases an application to the OWL-S ontology, in addition to a comprehensive
performance analysis that we carried out in order to test and compare the results obtained from proposed filters and
current discovery approaches, discussing the benefits of our proposal
A framework for deriving semantic web services
Web service-based development represents an emerging approach for the development of distributed information systems. Web services have been mainly applied by software practitioners as a means to modularize system functionality that can be offered across a network (e.g., intranet and/or the Internet). Although web services have been
predominantly developed as a technical solution for integrating software systems, there is a more business-oriented aspect that developers and enterprises need to deal with in order to benefit from the full potential of web services in an electronic market. This ‘ignored’ aspect is the representation of the semantics underlying the services themselves as well as the ‘things’ that the services manage. Currently languages like the Web Services Description Language (WSDL) provide the syntactic means to describe web services, but
lack in providing a semantic underpinning. In order to harvest all the benefits of web services technology, a framework has been developed for deriving business semantics from syntactic descriptions of web services. The benefits of such a framework are two-fold. Firstly, the framework provides a way to gradually construct domain ontologies from previously defined technical services. Secondly, the framework enables the
migration of syntactically defined web services toward semantic web services. The study follows a design research approach which (1) identifies the problem area and its relevance from an industrial case study and previous research, (2) develops the
framework as a design artifact and (3) evaluates the application of the framework through a relevant scenario
GSO: Designing a Well-Founded Service Ontology to Support Dynamic Service Discovery and Composition
A pragmatic and straightforward approach to semantic service discovery is to match inputs and outputs of user requests with the input and output requirements of registered service descriptions. This approach can be extended by using pre-conditions, effects and semantic annotations (meta-data) in an attempt to increase discovery accuracy. While on one hand these additions help improve discovery accuracy, on the other hand complexity is added as service users need to add more information elements to their service requests. In this paper we present an approach that aims at facilitating the representation of service requests by service users, without loss of accuracy. We introduce a Goal-Based Service Framework (GSF) that uses the concept of goal as an abstraction to represent service requests. This paper presents the core concepts and relations of the Goal-Based Service Ontology (GSO), which is a fundamental component of the GSF, and discusses how the framework supports semantic service discovery and composition. GSO provides a set of primitives and relations between goals, tasks and services. These primitives allow a user to represent its goals, and a supporting platform to discover or compose services that fulfil them
Methods for Efficient and Accurate Discovery of Services
With an increasing number of services developed and offered in an enterprise setting or the Web, users can hardly verify their requirements manually in order to find appropriate services. In this thesis, we develop a method to discover semantically described services. We exploit comprehensive service and request descriptions such that a wide variety of use cases can be supported. In our discovery method, we compute the matchmaking decision by employing an efficient model checking technique
A purely logic-based approach to approximate matching of Semantic Web Services
Most current approaches to matchmaking of semantic Web
services utilize hybrid strategies consisting of logic- and non-logic-based
similarity measures (or even no logic-based similarity at all). This is
mainly due to pure logic-based matchers achieving a good precision, but
very low recall values. We present a purely logic-based matcher implementation
based on approximate subsumption and extend this approach
to take additional information about the taxonomy of the background
ontology into account. Our aim is to provide a purely logic-based matchmaker
implementation, which also achieves reasonable recall levels without
large impact on precision
- …