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NautiLOD: A Formal Language for the Web of Data Graph

Published:23 January 2015Publication History
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Abstract

The Web of Linked Data is a huge graph of distributed and interlinked datasources fueled by structured information. This new environment calls for formal languages and tools to automatize navigation across datasources (nodes in such graph) and enable semantic-aware and Web-scale search mechanisms. In this article we introduce a declarative navigational language for the Web of Linked Data graph called NautiLOD. NautiLOD enables one to specify datasources via the intertwining of navigation and querying capabilities. It also features a mechanism to specify actions (e.g., send notification messages) that obtain their parameters from datasources reached during the navigation. We provide a formalization of the NautiLOD semantics, which captures both nodes and fragments of the Web of Linked Data. We present algorithms to implement such semantics and study their computational complexity. We discuss an implementation of the features of NautiLOD in a tool called swget, which exploits current Web technologies and protocols. We report on the evaluation of swget and its comparison with related work. Finally, we show the usefulness of capturing Web fragments by providing examples in different knowledge domains.

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          cover image ACM Transactions on the Web
          ACM Transactions on the Web  Volume 9, Issue 1
          January 2015
          178 pages
          ISSN:1559-1131
          EISSN:1559-114X
          DOI:10.1145/2726021
          Issue’s Table of Contents

          Copyright © 2015 ACM

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          Publication History

          • Published: 23 January 2015
          • Accepted: 1 October 2014
          • Revised: 1 August 2014
          • Received: 1 April 2014
          Published in tweb Volume 9, Issue 1

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