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Ph.D.
                                                                                 (Engineering & Technology)
          PERFORMANCE ENHANCEMENT OF SPARQL QUERY
          OVER THE SEMANTIC WEB


          Ph.D. Scholar : Nagar Bhaumik Chhotalal
          Research Supervisor : Dr. Naresh D. Jotwani



                                                                                Regi. No.: 11146051001
          Abstract :
          The internet is increasingly turning into a global information lake which contains not only
          linked documents, but also linked data. Querying linked data efficiently is essential with
          the  growth  of  the  inked  data  cloud.  Linked  data  is  always  in  the  form  of  Resource
          Description Framework (RDF) format. After the development of different prototypes for
          querying  this  cloud  linked  structured  data,  SPARQL  protocol  and  RDF  query  Language
          was developed and accepted by the World Wide Web consortium as the query language
          to  query  Linked  data.  Considering  the  growth  of  linked  data,  optimization  of  SPARQL
          query is essential as linked data cloud will further grow with more websites converging
          towards the Semantic Web.

          Tackling the issue of efficient data processing over the Semantic Web, we investigated
          the challenges that arises in the context of the standard Semantic Web data format RDF
          [rdfs]  and,  in  particular,  the    PARQL  query  language  for  RDF.  The  goal  was  to  bring
          together classical database research and the novel ideas behind the Semantic Web to
          enhance the performance of SPARQL query on Semantic Web. With the fast growth of the
          Semantic  Web,  a  large  amount  of  resource  description  framework  and  ontologies  are
          reated and published for knowledge sharing and integration for linked open data. SPARQL
          query optimization for querying large-scale resource description framework (RDF) triples
          is key part of semantic web data management. Performance of SPARQL query over the
          Semantic Web is always a concern because of the size of ontology. Before the SPARQL
          query  is  executed,  loading  the  ontology,  SPARQL  query  execution  uses  in-memory
          standard leviathan query processor and retrieve the required results from the ontology
          which  takes  lot  of  time.  There  is  a  possibility  of  enhancing  and  improving  the
          performance of SPARQL query. Due to inherent graph-structure of ontologies, querying
          large  RDF  datasets  requires  efficient  mechanisms  to  speed  up  the  retrieval  of
          information. However, these approaches involve many self-joins or cross-table-joins when
          processing queries, which greatly slows the query performance.

          We proposed an optimization technique on RDF or OWL i.e. by reducing Search Space
          using semantic similarity in SPARQL query comparison. This can be achieved by Then
          converting  the  SPARQL  query  into  equivalent  graph  and  use  the  semantic  similarity
          measures  to  compare  SPARQL  query  under  execution  with  already  executed  SPARQL
          query  in  the  system  Scope  of  search  space  can  be  reduced  in  ontology  by  marking
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