Emilia Cimpian

Semantically-enabled Service Oriented Architecture : Concepts, Technology and Application

Semantically enabled service-oriented architecture focused on principles of service orientation, semantic modeling, intelligent and automated integration defines grounds for a cutting-edge technology which enables new means to integration of services, more adaptive to changes in business requirements which occur over systems’ lifetime. We define the architecture starting from a global perspective and through Web service modeling ontology as its semantic service model we narrow down to its services, processes and technology we use for the reference implementation. On a B2B integration scenario we demonstrate several aspects of the architecture and further describe the evaluation of the implementation according to a community-agreed standard evaluation methodology for semantic-based systems.

An Ontology-Based Data Mediation Framework for Semantic Environments

In a semantic environment data is described by ontologies and ontology mapping has become a crucial aspect in solving the heterogeneity problems of semantically described data. This means that alignments between ontologies have to be created, most probably during design-time, and used in various run-time processes. Such alignments describe a set of mappings between the source and target ontologies, where the mappings show how instance data from one ontology can be expressed in terms of another ontology. In this article we propose a formal model for creation of mappings and we explore how such a model maps onto a design-time graphical tool that can be used in creating alignments between ontologies. In the other direction, we investigate how such a model helps in expressing the mappings in a logical language, based on the semantic relationships identified using the graphical tool.

A Semantic Web Mediation Architecture

Heterogeneity is an inherent characteristic of open and distributed environments like the Internet that can hamper Web resources and Web services from successful interoperation. Mediation can be used to resolve these issues, which are critical problems in the Semantic Web. Appropriate technologies for mediation need to cover two aspects: first, techniques for handling the different kinds of heterogeneity that can occur between Web resources, and secondly logical components that connect resources and apply required mediation technique along with invocation and execution facilities. This paper presents an integrated model for mediation on the Semantic Web with special attention to Semantic Web services that is developed around the Web Service Modeling Ontology WSMO. Covering both dimensions, we explain the techniques developed for handling different types of heterogeneity as well as the components and architecture for establishing interoperability on the Semantic Web if not given a priori.

Filling the Gap - Extending Service Oriented Architectures with Semantics

The problems of integrating information and processes between businesses continue to represent a challenge for which no universal solution has been found. Service oriented architecture (SOA) represents a technology leap in this direction, allowing businesses to define the functionality of their various systems as discrete, loosely coupled services, accessible through well defined interfaces. Augmenting the SOA approach with semantics guarantees unambiguous Web service descriptions and explicit meaning for the data they interchange. We describe an example to motivate semantic enhancement and present WSMX as a semantic execution environment addressing the search and integration challenges. We propose that using WSMX, complex collaboration scenarios can be built in a dynamic fashion, sustained by concrete solutions that solve heterogeneity issues at the data, process and protocol levels

Investigating Semantic Web Service Execution Environments: A Comparison between WSMX and OWL-S Tools

The application of semantics in Web services as semantic Web services for dynamic discovery, composition, invocation and monitoring has been very helpful in enabling Enterprise Application Integration and E-Commerce. There are many initiatives that aim to realize the semantic Web services to enable effective exploitation of semantic annotations, and two major of them are Web service modeling ontology (WSMO) and ontology Web language for services (OWL-S). Several tools have been developed to realize both the conceptual models i.e. Web services execution environment (WSMX) is the reference implementation for WSMO, on the other side OWL-S reference implementation exists in the form of loose collection of individual tools like OWL-S Editor, OWL-S matchmaker, OWL-S virtual machine, OWL-S IDE, WSDL20WL-S converter and OWL-S2UDDI converter etc. In this paper, we have conducted a comparison of both the reference implementations to identify similarities and differences between them and to evaluate their potential to become widely accepted implementation recommendations.

BPMO: Semantic Business Process Modeling and WSMO Extension

To actually bridge the gap between business perspective and technical perspective, the prerequisite is to provide a comprehensive process modeling framework for business processes. Different from the previous traditional process methodologies, our work is neither only industrial process graphic-modeling nor pure theoretical studies. We mainly focus on the semantically-enhanced process description model. We propose the semantic modeling framework for business processes, i.e. BPMO: basically, we determine the description requirements for the whole business process lifecycle involving process discovery, composition and execution; furthermore, we refine the comprehensive semantic Web services conceptual model WSMO and make specific extensions to realize the BPMO modeling framework.

Process mediation based on triple space computing

Web services are inherently heterogeneous at both data and behavioral levels because of the nature of the Web, which is the main obstacle to the usability of Web services. The heterogeneity at a behavioral level is generally addressed by process mediation, in which the message flow is adjusted to suit the behavior of Web services involved in a given interaction. In this paper, we present a novel approach for process mediation, and propose an architectural for process mediation based on Triple Space Computing to solve resolvable message sequence mismatches. These resolvable mismatches can be classified into five classes for unveiling their essence. This work provides a basis for the generalization of mismatches themselves, as well as a potentially uniform solution to address these mismatches.

Ontologies and Matchmaking

The word ontology is used with different meanings in different communities. We distinguish between Ontology (uncountable reading and capital initial) and an ontology (countable reading and lower-case initial). In the first case, we refer to a philosophical discipline, namely the branch of philosophy which deals with the nature and the organisation of reality. Unlike the special sciences, each of which investigates a class of beings and their determinations, Ontology regards all the species and tries to answer the question: What is being?, or What are the features common to all beings? In the second case, we refer to an information object and engineering artefact as the most prevalent use in the computer science communities.