Adrian Mocan

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.

WSMO-PA: Formal Specification of Public Administration Service Model on Semantic Web Service Ontology

In this paper we define a formal model for a public administration service on the basis of the Web service modeling ontology (WSMO). For this purpose we employ the generic public service object model of the governance enterprise architecture (GEA) providing a PA domain specific semantics. We investigate conceptual mappings between PA entities and WSMO elements, and on the real-world use case present the detailed formal PA service model based on the WSMO service model

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.

The Web Service Modeling Toolkit - An Integrated Development Environment for Semantic Web Services

The time of engineers is a precious commodity. This is especially true for engineers of semantic descriptions, who need to be highly skilled in conceptual modeling, a skill which will be in high demand as Semantic Web technologies are adopted by industry. Within the software engineering community Integrated Development Environments (IDEs) like the Eclipse Java Development Toolkit and NetBeans have proved to increase the productivity of engineers by bringing together tools to help engineers with their everyday tasks. This paper motivates the need for such an IDE for the Semantic Web and in particular describes the Web Service Modeling Toolkit (WSMT), an Integrated Development Environment for Semantic Web Services through the WSMO paradigm.

WWW: WSMO, WSML, and WSMX in a nutshell

This paper presents, in a nutshell, a unifying framework for conceptually modeling, formally representing, and executing Semantic Web services We first introduce a conceptual model for representing Semantic Web services and its design principles, then we present a language based on different logical formalisms used to express Semantic Web services that are compliant with our conceptual model Finally, a high level overview of an execution environment, and its relations to the conceptual model and the language introduced in this paper, are presented.

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

Solving Semantic Interoperability Conflicts in Cross-Border E-Government Services

Interoperability is one of the most challenging problems in modern cross-organizational information systems, which rely on heterogeneous information and process models. Interoperability becomes very important for e-Government information systems that support cross-organizational communication especially in a cross-border setting. The main goal in this context is to seamlessly provide integrated services to the user (citizen). In this paper we focus on Pan European e-Services and issues related with their integration. Our analysis uses basic concepts of the generic public service model of the Governance Enterprise Architecture (GEA) and of the Web Service Modeling Ontology (WSMO), to express the semantic description of the e-services. Based on the above, we present a mediation infrastructure capable of resolving semantic interoperability conflicts at a pan-European level. We provide several examples to illustrate both the need to solve such semantic conflicts and the actual solutions we propose.

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.

Modeling Semantic Web Services with the Web Service Modeling Toolkit

The lack of any methodology for modeling Semantic Web Services means that developers wishing to utilize technologies like the Web Service Modeling Ontology, the Web Service Modeling Language, and the Web Service Execution Environment are lost in a Semantic wilderness with no road signs to guide them on their way. This paper presents an initial guide for developers wishing to model Semantic Web Services, along with a description of the Web Service Modeling Toolkit that provides tool support for the activities that must be conducted by the developer in this process.