A P2P and SOA Infrastructure for Distributed Ontology-Based Knowledge Management (original) (raw)
2002
The real value of Semantic Web vision can be demonstrated if people and applications can create and discover new and interesting knowledge and share this knowledge in a transparent manner similar to the way data is exchanged today. Therefore, we believe that Semantic Web will consist of a distributed environment of shared and interoperable ontologies, which have emerged as common formalisms for knowledge representation. The users will need to discover new ontologies, which are not known to them before and use them to either annotate the content or to formulate their information requests. This requires an environment that supports creating, maintaining, and controlled sharing of ontologies. We believe that a Peer-to-Peer (P2P) infrastructure can enable such capabilities. We call our approach P2P Semantic Web (PSW) with capabilities to find relevant set of ontologies, facilitating reuse of existing ontologies to create additional ontologies, and advertising the resulting ontologies. We discuss an ontology driven search of concepts and services and exploration of inter-ontological relationships over a P2P infrastructure. The prototyping of this approach in the InfoQuilt system is also discussed.
Sharing Ontology in Complex Scenario using a Peer-To-Peer Approach
International Journal of Computer Information Systems …
The problem of defining efficient techniques for knowledge representation (KR) is becoming more and more a challenging topic in both academic and industrial community. The Semantic Web needs of formal knowledge representations for implementing useful services and put in common the different views between man and machines. In this framework, we assume that new approaches for knowledge definition and representation may be useful, in particular the ones based on the concept of ontology. We chose the issue of landscape planning as a case study, particularly focusing on cultural landscape. This choice was motivated by cultural and scientific innovations, which led in recent years to a completely new interpretation of landscape making it a high complex scenario. Based on these considerations, we propose a suitable ontology-based model and implement it in a system designed to manage ontologies using a peer-to-peer (P2P) paradigm to share general and domain knowledge. The network knowledge is exposed using a Web Service and it can be used by intelligent Web agents. * Sections 1, 2, 6, and 7 are by both authors; sections 3 and Appendix A are by A. Cataldo; sections 4 and 5 are by A.M. Rinaldi.
We present a system called "OntoZilla", which combines ontologies and peer-to-peer (P2P) technology, with a vision of improving the information search process and facilitating greater integration as well as interoperability. In OntoZilla, peers supporting the same concept are grouped into the same cluster, and the relationships between clusters are modeled according to the concepts they specialize in. Therefore, a query belonging to a specific concept can be routed to the suitable group of peers in a systematic way, thus supporting efficient concept search. Moreover, since peer relationships are based on peers' expertises which may change over time, our semi-structured system can flexibly cope with the changing environment as peers evolve.
A Scalable and Ontology-Based P2P Infrastructure for Semantic Web Services
2002
Semantic Web Services are a promising combination of Semantic Web and Web service technology, aiming at providing means of automatically executing, discovering and composing semantically marked-up Web services. We envision peer-to-peer networks which allow for carrying out searches in real-time on permanently reconfiguring networks to be an ideal infrastructure for deploying a network of Semantic Web Service providers. However, P2P networks evolving in an unorganized manner suffer from serious scalability problems, limiting the number of nodes in the network, creating network overload and pushing search times to unacceptable limits. We address these problems by imposing a deterministic shape on P2P networks: We propose a graph topology which allows for very efficient broadcast and search, and we provide an efficient topology construction and maintenance algorithm which, crucial to symmetric peer-to-peer networks, does neither require a central server nor super nodes in the network. We show how our scheme can be made even more efficient by using a globally known ontology to determine the organization of peers in the graph topology, allowing for efficient concept-based search.
Ontology-based data sharing in p2p databases
Swdb Odbis, 2007
We consider peer-to-peer systems in which peers share structured data through the use of schema mappings. Peers express their queries and rewrite incoming queries on their local schema. We assume the existence of one or more ontologies describing the domain of interest of the peers. The ontologies are used to semantically annotate each peer schema, making explicit the type of information provided by it. A major problem in such a system is that peers cannot easily judge the semantic relativeness of their interests to interests of other peers, as these are expressed by the respective local schemas. Moreover, peers cannot evaluate the semantic relativeness of answers that they receive to their queries. In this paper, we propose a semantic similarity measure for evaluating the semantic relativeness between peer schemas, as well as between queries and their rewritten versions on other peers. The similarity measure is first introduced under the assumption of a shared ontology among the community of peers, and then it is extended, employing ontology matching and translation techniques, to support the comparison of class expressions accross multiple ontologies. The proposed similarity measure adopts the notions of recall and precision from the field of Information Retrieval. Our goal is to use this measure for the identification of semantically relevant peers and the evaluation of the quality of the received answers based on the semantic annotations, the mappings, and the queries issued.
Oyster – Sharing and Re-using Ontologies in a Peer-to-Peer Community
Lecture Notes in Computer Science, 2005
This paper presents Oyster, a Peer-to-Peer system for exchanging ontology metadata among communities in the Semantic Web. We describe how Oyster assists researchers in re-using existing ontologies, and how Oyster exploits semantic web techniques in data representation, query formulation, query result presentation to provide an online solution to share ontologies.
A framework for distributed knowledge management: Design and implementation
Future Generation Computer Systems, 2010
This paper describes a framework for implementing distributed ontology-based knowledge management systems (DOKMS). The framework, in particular, focuses on knowledge management within organizations. It investigates the functional requirements to enable Individual Knowledge Workers (IKWs) and distributed communities (e.g., project teams) to create, manage and share knowledge with the support of ontologies. On the one hand, the framework enables distributed and collaborative work by relying on a P2P virtual office model. On the other hand, it provides a multi-layer ontology framework to enable semantics-driven knowledge processing. The ontology framework allows organizational knowledge to be modeled at different levels. An Upper Ontology is exploited to establish a common organizational knowledge background. A set of Workspace Ontologies can be designed to manage, share and search knowledge within communities by the establishment of a contextual (i.e., related to the aim of a group) understanding. Finally, Personal Ontologies support IKWs in personal knowledge management activities. We present an implementation of the designed framework in the K-link+ system and show the suitability of this approach through a use case. The evaluation of K-link+ in a real network is also discussed.
An ontology and peer-to-peer based data and service unified discovery system
Expert Systems With Applications, 2009
The next generation Internet has the potential ability to be a ubiquitous and pervasive medium communication carrier for all types of information. The World Wide Web is emerging with a broader variety of resources that include both data and services. Yet, a lot of research work focused on either service discovery or data discovery although they cannot be separated from each other. In addition, the current Network, due to its decentralized nature and weak support for semantic, is still chaotic and lacks of the ability to allow users to discover, extract and integrate information of interest from heterogeneous sources. In this paper, we present a scalable, high performance system for data and service unified discovery, and to increase the success rate, an ontology-based approach is used to describe data and services. As for service, we add quality of service (QoS) information to OWL-S files to get more accurate results for users. Moreover, we also bring JXTA, which is a suitable foundation to build future computer systems on, to our system.