This book constitutes the refereed proceedings of the 4th European Semantic Web Conference, ESWC 2007, held in Innsbruck, Austria, in June 2007. Coverage includes semantic Web services, ontology learning, inference and mapping, social semantic Web, ontologies, personalization, foundations of the semantic Web, natural languages and ontologies, and querying and Web data models.

Inhalt
Invited Talks.- Emerging Sciences of the Internet: Some New Opportunities.- Design Abstractions for Innovative Web Applications: The Case of the SOA Augmented with Semantics.- The Lixto Systems Applications in Business Intelligence and Semantic Web.- Ways to Develop Human-Level Web Intelligence: A Brain Informatics Perspective.- Best Papers.- Empowering Software Maintainers with Semantic Web Technologies.- Minimal Deductive Systems for RDF.- Semantic Web Services.- Web Service Contracting: Specification and Reasoning with SCIFF.- Dynamic Service Discovery Through Meta-interactions with Service Providers.- Two-Phase Web Service Discovery Based on Rich Functional Descriptions.- A Reasoning Framework for Rule-Based WSML.- Ontology Learning, Inference and Mapping I.- GenTax: A Generic Methodology for Deriving OWL and RDF-S Ontologies from Hierarchical Classifications, Thesauri, and Inconsistent Taxonomies.- SPARQLeR: Extended Sparql for Semantic Association Discovery.- Simple Algorithms for Predicate Suggestions Using Similarity and Co-occurrence.- Learning Disjointness.- Case Studies.- Developing Ontologies for Collaborative Engineering in Mechatronics.- Media, Politics and the Semantic Web.- SEEMP: An Semantic Interoperability Infrastructure for e-Government Services in the Employment Sector.- Combining RDF Vocabularies for Expert Finding.- Social Semantic Web.- Extracting Social Networks Among Various Entities on the Web.- Towards Semantic Social Networks.- Knowledge Sharing on the Semantic Web.- Ontologies: Requirements and Analysis.- Real-World Reasoning with OWL.- How to Design Better Ontology Metrics.- Measuring Inconsistencies in Ontologies.- Personalization I.- Squirrel: An Advanced Semantic Search and Browse Facility.- User-Centric Faceted Search for Semantic Portals.- An Approach for Identification of User's Intentions During the Navigation in Semantic Websites.- Foundations of the Semantic Web.- A Novel Combination of Answer Set Programming with Description Logics for the Semantic Web.- Algorithms for Paraconsistent Reasoning with OWL.- Vague Knowledge Bases for Matchmaking in P2P E-Marketplaces.- Symbol Grounding for the Semantic Web.- Natural Languages and Ontologies.- Ontology-Driven Semantic Ranking for Natural Language Disambiguation in the OntoNL Framework.- Web-Annotations for Humans and Machines.- PANTO: A Portable Natural Language Interface to Ontologies.- Mining the Web Through Verbs: A Case Study.- Applications.- What Have Innsbruck and Leipzig in Common? Extracting Semantics from Wiki Content.- SALT - Semantically Annotated for Scientific Publications.- Annotating Relationships Between Multiple Mixed-Media Digital Objects by Extending Annotea.- Describing Ontology Applications.- Querying and Web Data Models.- The SPARQL Query Graph Model for Query Optimization.- A Unified Approach to Retrieving Web Documents and Semantic Web Data.- Distributed Knowledge Representation on the Social Semantic Desktop: Named Graphs, Views and Roles in NRL.- Semantic Process Retrieval with iSPARQL.- Ontology Learning, Inference and Mapping II.- Integrating Folksonomies with the Semantic Web.- IdentityRank: Named Entity Disambiguation in the Context of the NEWS Project.- A Study in Empirical and 'Casuistic' Analysis of Ontology Mapping Results.- Acquisition of OWL DL Axioms from Lexical Resources.- Personalization II.- On Enriching Ajax with Semantics: The Web Personalization Use Case.- A Semantic Web Service Oriented Framework for Adaptive Learning Environments.- Semantic Composition of Lecture Subparts for a Personalizede-Learning.- System Descriptions.- Caravela: Semantic Content Management with Automatic Information Integration and Categorization (System Description).- The NExT System: Towards True Dynamic Adaptations of Semantic Web Service Compositions.- WSMO Studio A Semantic Web Services Modelling Environment for WSMO.- An Annotation Tool for Semantic Documents.- SWHi System Description: A Case Study in Information Retrieval, Inference, and Visualization in the Semantic Web.- Semantic Turkey: A Semantic Bookmarking Tool (System Description).- The Web Service Modeling Toolkit - An Integrated Development Environment for Semantic Web Services.- Understanding Large Volumes of Interconnected Individuals by Visual Exploration.- System Description: An Orienteering Strategy to Browse Semantically-Enhanced Educational Wiki Pages.- Efficient Content Creation on the Semantic Web Using Metadata Schemas with Domain Ontology Services (System Description).