Part I: Information Retrieval in Digital Libraries -- Introduction to Digital Libraries -- Search Engines -- Part II: Key Technologies of E-Librarian Services -- Semantic Web and Ontologies -- Description Logics and Reasoning.- Natural Language Processing -- Multimedia Information Retrieval.- Part III: Design and Utilization of E-Librarian Services -- Ontological Approach -- Design of the Natural Language Processing Module -- Designing the Multimedia Information Retrieval Module -- Implementation, Configuration, and Deployment -- Best Practices -- Part IV: Appendix -- A - XML SChema Primitive Datatypes -- B - Reasoning Algorithms -- C - Syntactic Difference -- D - Brown Tag Set -- E - Part-of-Speech-Taggers and Parsers -- References.

This book introduces a new approach to designing E-Librarian Services. With the help of this system, users will be able to retrieve multimedia resources from digital libraries more efficiently than they would by browsing through an index or by using a simple keyword search. E-Librarian Services combine recent advances in multimedia information retrieval with aspects of human-machine interfaces, such as the ability to ask questions in natural language; they simulate a human librarian by finding and delivering the most relevant documents that offer users potential answers to their queries. The premise is that more pertinent results can be retrieved if the search engine understands the meaning of the query; the returned results are therefore logical consequences of an inference rather than of keyword matches. Moreover, E-Librarian Services always provide users with a solution, even in situations where they are unable to offer a comprehensive answer.