Research topics Semantic Web - Spring 2007 Computer Engineering Department Sharif University of Technology

2 Information search One of the main promises of the semantic web is to provide a more accurate search mechanism Semantic web search therefore uses meaning (explicit or implicit) into account for the query processing The semantic can be shallow like synonymy consideration or more deep like finding objects with specific attributes and relations

3 Annotation A lot of information exists in web in the form of texts It is almost impossible to make Semantic Web version of them manually Annotation aims to resolve this issue Techniques involves NLP, ML, IR and DM

4 Ontology Alignment Ontologies provide shared vocabularies However two parties may develop separate Ontologies which talks about similar things Then an agent wants to be able to process and find similar data in two sites should be able to draw correspondence between entities of two or more ontologies Techniques ranges from simple lexical similarity computation towards more deep models of instance based and graph matching

5 Social Networks Web and specially semantic web is a place for social interactions Web 2.0 provides blogs and Wiki, and RSS which is now very popular Adding semantics allows agents to use such information as well as human Foaf is a simple example But other social structures can be built and reasoned

6 Ontology Integration Having some ontologies the aim is to build a new onotolgy which integrates the input ontologies Ontology alignment techniques can be used here But other mechanism is needed to build appropriate structure for the integrated ontology

7 Semantic Web Services Web services are functions deployed on the web which can be located and called on the web It is a based for so called B2B, B2E and E2E models of interactions However, human should interfere in every step of locating and usage of them This is because web service descriptions in traditional forms are contain no semantic With semantic web services we hope that by adding semantics we may delegate some of the human works to machines These involves web service discovery and composition

8 Catalogues matching There are already some de-facto standards for business catalogue respresentations (e.g. xCBL) They are used to provide common representation of products of different companies Such cataloging languages are still at syntactic level Catalogue matching like the general ontology matching problem aims at providing a mapping between entities of different catalogue entities

9 Reasoning There are some standard reasoning tasks for Ontology languages (e.g. Subsumption) However some other forms of reasoning is needed for many applications For RDF there are already some defined query languages and query processing approaches However it is still an active research area to provide more advanced reasoning tasks for more specific tasks

10 Semantic web and P2P P2P provides a convenient environment for sharing of resources SW can help P2P for better mechanism for resource location and distribution For example we can divide a P2P space to semantic regions with nodes assigned to regions based on their resources or some other measures

11 Theory, applications and tools Theory should be extended to fulfill new requirements. We need to provide new languages, logics, and reasoning Many applications can be imagined for SW like SWSE There are already some basic tools for working on Ontologies and using them

12 Trust models Here we are interested to provide formal models for trust management in web These involves the definition of new languages for trust assertions and rules as well as reasoning mechanisms to query such trust models

13 Semantic Web Mining Web mining helps to find new patterns and knowledge from the web information Semantic Web Mining can be used to find semantic patterns or use the semantic to guide mining for better knowledge extraction from the web