Dr. Harald Sack

Hasso Plattner Institute for IT Systems Engineering

University of Potsdam

Spring 2013

Semantic Web Technologies

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Lecture 1: The Web of Data 02: The Limits of the Web

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of 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 Institute, University of Potsdam

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02: The Limits of the Web ... OpenHPI - Course Semantic Web Technologies - Lecture 1: The Web of Data

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

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How can we find somethingin the Web?

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

current solution:

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Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

The Web is big. Really big. You just won't believe how vastly, hugely, mind-bogglingly big it is.(...according to Douglas Adams)

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Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

The Web is really big...•ca. 25 x 109 indexed documents in search engines

(TNL Blog: Google has 24 billion items index, considers MSN search nearest competitor, September 2005)

•Web Crawler: > 1012 (1 trillion) documents(The Official Google Blog: We knew the Web was Big....., Juli 25, 2008)

•Google Search Index Caffeine comprises ca.100 Million Gigabytes i.e. 1017 Byte (SMX Video: Google’s Matt Cutts On Caffeine Launch, June 9, 2010,

http://searchengineland.com/smx-video-googles-matt-cutts-on-caffeine-launch-43933)

•DeepWeb (Darkweb) estimated to be about 550 times bigger than Surface Web (Bergman, 2001)

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Dr. Harald Sack, Hasso-Plattner-Institut Potsdam, Workshop: Interaktion und Visualisierung im Datenweb (IVDW 2012), Braunschweig, 20.09.2012

...and it‘s getting bigger every minute!

Dr. Harald Sack, Hasso-Plattner-Institut Potsdam, Workshop: Interaktion und Visualisierung im Datenweb (IVDW 2012), Braunschweig, 20.09.2012

http://www.visualnews.com/2012/06/19/how-much-data-created-every-minute/

Dr. Harald Sack, Hasso-Plattner-Institut Potsdam, Workshop: Interaktion und Visualisierung im Datenweb (IVDW 2012), Braunschweig, 20.09.2012

http://www.visualnews.com/2012/06/19/how-much-data-created-every-minute/

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

10 Multimedia, Real-Time Data, Sensor Data, ....

Semantic Web Technologien Quo vadis WWW ?

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

11 Multimedia, Real-Time Data, Sensor Data, ....

Semantic Web Technologien Quo vadis WWW ?

Vorlesung Semantic Web, Dr. Harald Sack, Hasso-Plattner-Institut, Universität Potsdam

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and all the things will connect with social networks...

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

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Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

13 • what is important and how do you know?

• what is information, what is advertisement?

• what does the information mean?

• how credible/trustworthy is the information?

• what belongs together?• what is redundant?

• Humans have contextual knowledge, world knowledge and experience to solve the problem

Information in the WWW

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

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• The Web is supposed to be used by humans

• The Web is based on the markup language HTML

• HTML describes

• how information is presented

• how information is linked

• but not, what the information means

Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

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Semantic Web Technologies , Dr. Harald Sack, Hasso Plattner Institute, University of Potsdam

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GAME OVER

03: The Importance of Meaning OpenHPI - Course Semantic Web Technologies - Lecture 1: The Web of Data

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