ontology engineering

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1 Ontology Engineering Introduction

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Ontology Engineering. Introduction. First results are about bats and dolphins. Google Scholar search for query Sentiment Analysis. Why?. Web content is currently formatted for human readers rather than programs - PowerPoint PPT Presentation

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Page 1: Ontology Engineering

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Ontology Engineering

Introduction

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Page 3: Ontology Engineering

First results are about bats and dolphins

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Google Scholar search for query Sentiment Analysis

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Sr. No

Query on GS

Returned Results

Years needed to finish the reading (five papers per day)

Citations of top 10 results

Years needed to finish reading of citations (five papers per day)

1 Digital Libraries

1.8 million

936 years 3411 1.8 years

2 Ontology Evaluation

343,000

188 years 1073 Half year

3 Schema integration

427,000

234 years 3389 1.8 years

4 Requirement Engineering

1.4 million

761 years 341 0.2 years

5 Turing Machines

154,000

84 years 3957 2.2 years

6 Distributed computing models

2.2 million

1238 years 5469 3 years

7 Fuzzy Logic

1 million

507 years 27154 15 years

8 Hypermedia

176,000

96 years 12359 6.7 years

9 Virtual Reality

1.9 million

1030 years 17098 9.3 years

10 Fault Tolerance

601,000

329 years 7246 4 years

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Why?

Web content is currently formatted for human readers rather than programs

HTML is the predominant language in which Web pages are written (directly or using tools)

Vocabulary describes presentation

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HTML?

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<HTML><BODY><H2 align=center>Nonmonotonic Reasoning: Context-

Dependent Reasoning</H2><P align=center>

<I>by<B>V. Marek</B> and <B>M Truszczynski</B></I>

<BR>Springer 1993<BR>ISBN 0387976892</P></BODY></HTML>

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HTML?

Inability to cover any content aspects – HTML only describes the appearances of documents and cannot cover any content related aspects. It is therefore unsuitable for explicit queries.

Inability for semantic markup – Individual elements on a page cannot be marked semantically.

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Why does this happen??

The Web content is not machine-accessible lack of semantics Not in a proper structure Not in a machine understandable

manner keyword-based search engines

(e.g. Google, AltaVista, Yahoo)

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How to overcome these limitations Currents situation can be improved by adopting following

two strategies Use the content as it is represented today, and to develop

techniques based on artificial intelligence and computational linguistics. This approach has been followed for sometime now, but

despite advances that have been made the task still appears too ambitious.

Represent Web content in a form that is more easily machine processable

Then use intelligent techniques to take advantage of these representations (Semantic Web).

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A Layered Approach

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XML

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