openhpi 1.4 - the limits of the web (continued)
DESCRIPTION
Free online Lecture "Semantic Web Technologies" at OpenHPI. Visit the Course website, registration is free. You will find the lecture recordings as mp3 and also as video at https://openhpi.de/course/semanticwebTRANSCRIPT
Dr. Harald Sack
Hasso Plattner Institute for IT Systems Engineering
University of Potsdam
Spring 2013
Semantic Web Technologies
This file is licensed under the Creative Commons Attribution-NonCommercial 3.0 (CC BY-NC 3.0)
Lecture 1: The Web of Data 04: The Limits of the Web (continued)
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
Lecture 1: The Web of Data
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Open HPI - Course: Semantic Web Technologies
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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04: The Limits of the Web (continued) OpenHPI - Course Semantic Web Technologies - Lecture 1: The Web of Data
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Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 1: Information Retrieval
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 1: Information Retrieval
•traditional keyword-based search leads to many not relevant results•different meanings•polysemy•different contexts
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 1: Information Retrieval
•traditional keyword-based search does not find all results•synonyms and metaphors•missing context definition
Jaguar
Panthera Onca
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 2: Information Extraction
What does the information mean?
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 2: Information Extraction
What does the information mean?
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 2: Information Extraction
Information Extraction•can only be solved ,correctly‘ by a human agent
•heterogeneous distribution and order of information
•Software agent does not have sufficient
•knowledge of contexts
•world knowledge and
•experience
•to solve the problem
Problemfeld 2: Informationsextraktion
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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•implicit knowledge, i.e. information does not have specified explicitely, but must be derived via logical deductions from available information.
Problem 2: Information Extraction
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 3: Maintenance
•the more complex and voluminous a website, the more complicated is the maintenance of the only weakly structured data.
•Problems:•syntactic and semantic (link)
consistency•correctness•timeliness
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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Problem 4: Personalization
•Adaption of the presented information content to personal requirements
•Problems: •from where do we get the
required (personal) information?
•personalization vs. data security
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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GAME OVER
Semantic Web Technologies , Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam
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05: The Vision of the Semantic Web OpenHPI - Course Semantic Web Technologies - Lecture 1: The Web of Data
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