Christoph Bussler

The Semantic Web: Research and Applications

In order to realize the on-the-fly ontology construction for the Semantic Web, this paper proposes DODDLE-R, a support environment for user-centered ontology development. It consists of two main parts: pre-processing part and quality improvement part. Pre-processing part generates a prototype ontology semi-automatically, and quality improvement part supports the refinement of it interactively. As we believe that careful construction of ontologies from preliminary phase is more efficient than attempting generate ontologies full-automatically (it may cause too many modification by hand), quality improvement part plays significant role in DODDLE-R. Through interactive support for improving the quality of prototype ontology, OWL-Lite level ontology, which consists of taxonomic relationships (class sub class relationship) and non-taxonomic relationships (defined as property), is constructed effi-

Web Service Modeling Ontology

The potential to achieve dynamic, scalable and cost-effective marketplaces and eCommerce solutions has driven recent research efforts towards so-called Semantic Web Services that are enriching Web services with machine-processable semantics. To this end, the Web Service Modeling Ontology (WSMO) provides the conceptual underpinning and a formal language for semantically describing all relevant aspects of Web services in order to facilitate the automatization of discovering, combining and invoking electronic services over the Web. In this paper we describe the overall structure of WSMO by its four main elements: ontologies, which provide the terminology used by other WSMO elements, Web services, which provide access to services that, in turn, provide some value in some domain, goals that represent user desires, and mediators, which deal with interoperability problems between different WSMO elements. Along with introducing the main elements of WSMO, we provide a logical language for defining formal statements in WSMO together with some motivating examples from practical use cases which shall demonstrate the benefits of Semantic Web Services.

The Web Service Modeling Framework WSMF

Abstract Web services will transform the web from a collection of information into a distributed computational device. In order to employ their full potential, appropriate description means for web services need to be developed. For this purpose, we define a fully-fledged Web Service Modeling Framework (WSMF) that provides the appropriate conceptual model for developing and describing web services and their composition (complex web services). In a nutshell, its philosophy is based on the following principle: maximal de-coupling complemented by a scalable mediation service .

WSMX - a semantic service-oriented architecture

Web services offer an interoperability model that abstracts from the idiosyncrasies of specific implementations; they were introduced to address the increasing need for seamless interoperability between systems in the business-to-business domain. We analyse the requirements from this domain and show that to fully address interoperability demands we need to make use of semantic descriptions of Web services. We therefore introduce the Web service execution environment (WSMX), at software system that enables the creation and execution of semantic Web services based on the Web service modelling ontology. Providers can use it to register and offer their services and requesters can use it to dynamically discover and invoke relevant services. WSMX allows a requester to discover, mediate and invoke Web services in order to carry out its tasks, based on services available on the Internet.

Web services: been there, done that?

Web services can be defined as loosely coupled, reusable software components that semantically encapsulate discrete functionality and are distributed and programmatically accessible over standard Internet protocols. Web services have received a lot of hype, the reasons for which are not easily determined. Some of their benefits might even seem to waste away, once we touch on the nitty-gritty details, because Web services per se do not offer a solution to underlying problems. The contributions included in this section delve into some of these issues, including: pitfalls of workflow issues; structuring procedural knowledge into problem-solving methods; discussing how a low initial entry barrier and simple technology are balanced against the long-term goal of easy integration; including semantics in a Web service modeling framework; and building on new kinds of applications such as grid enterprises.

A conceptual architecture for semantic web enabled web services

Semantic Web Enabled Web Services (SWWS) will transform the web from a static collection of information into a distributed device of computation on the basis of Semantic technology making content within the World Wide Web machine-processable and machine-interpretable. Semantic Web Enabled Web Services will allow the automatic discovery, selection and execution of inter-organization business logic making areas like dynamic supply chain composition a reality. In this paper we introduce the vision of Semantic Web Enabled Web Services, describe requirements for building semantics-driven web services and sketch a first draft of conceptual architecture for implementing semantic web enabled web services.

The role of B2B engines in B2B integration architectures

Semantic B2B Integration architectures must enable enterprises to communicate standards-based B2B events like purchase orders with any potential trading partner. This requires not only back end application integration capabilities to integrate with e.g. enterprise resource planning (ERP) systems as the company-internal source and destination of B2B events, but also a capability to implement every necessary B2B protocol like Electronic Data Interchange (EDI), RosettaNet as well as more generic capabilities like web services (WS). This paper shows the placement and functionality of B2B engines in semantic B2B integration architectures that implement a generic framework for modeling and executing any B2B protocol. A detailed discussion shows how a B2B engine can provide the necessary abstractions to implement any standard-based B2B protocol or any trading partner specific specialization.

Semantic Web Enabled Web Services

Web Services will transform the web from a collection of information into a distributed device of computation. In order to employ their full potential, appropriate description means for web services need to be developed. For this purpose we define a full-fledged Web Service Modeling Framework (WSMF) that provides the appropriate conceptual model for developing and describing web services and their composition. Its philosophy is based on the following principle: maximal decoupling complemented by scalable mediation service.

Implementing agent coordination for workflow management systems using active database systems

A new way to enact business processes in enterprises is to deploy workflow technology. Workflow systems are proactive computer systems, which orchestrate the execution of long-living processes. Process agents, i.e. members of the organization structures of an enterprise, are in charge of executing processes and process steps. Workflow management systems have do associate appropriate process agents to processes proactively. We call this task process agent coordination. We show that ECA rules implemented on top of active database systems are suitable to facilitate agent coordination in workflow management systems.<<ETX>>

Policy resolution for workflow management systems

We introduce policy resolution (PR) for workflow management systems (WFMS) as service to assign work to agents. Policy resolution is a framework for defining arbitrary role and organization models together with operations suiting the needs of workflow management systems.<<ETX>>