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KOM - Multimedia Communications LabProf. Dr.-Ing. Ralf Steinmetz (director)
Dept. of Electrical Engineering and Information TechnologyDept. of Computer Science (adjunct professor)
TUD – Technische Universität Darmstadt Merckstr. 25, D-64283 Darmstadt, Germany
Tel.+49 6151 166150, Fax. +49 6151 166152 www.KOM.tu-darmstadt.de
httc –Hessian Telemedia Technology
Competence-Center e.V - www.httc.de
12. August 2010© 2010 author(s) of these slides including research results from the KOM research network and TU Darmstadt. Otherwise it is specified at the respective slideICCCN_2010_08_05
Recommending and finding multimedia resources in knowledge acquisition
based on Web resources
Dr.-Ing. Christoph RensingTel. +49 6151 16 [email protected]
This work was supported by funds from the German Federal Ministry of Education and Research under the mark 01 PF 08015 A and from the European Social Fund of the European Union (ESF).
KOM – Multimedia Communications Lab 2
Outline
Scenario: Learning / Knowledge Acquisition based on Web Resources
CROKODIL – a platform for collaborative Knowledge Acquisition based on Web Resources
Concept & Usage of Semantic NetworksFinding and Recommendation of Resources
Conclusion & Outlook
KOM – Multimedia Communications Lab 3
Resources used for Learning and Knowledge Acquisition
Learning Resources Animation
…
Web BasedTrainings
Teaching Material
E-Lecture
Social (Web)Resources WiKis
FAQsBulletin/
DiscussionBoards Video Coll.
Picture Coll.
Blogs
(Sources: slidestar.net, youtube.com, wehow.com)
KOM – Multimedia Communications Lab 4
Challenges of Resource-Based Learning using Web Resources
RBL applied to learning with web resources rise many challenges:Huge variety and quantity of possibly relevant resources
Finding relevant / authoritative / trusted resources is no easy taskNot explicitly intended for learning – different audiencesAll relevant information is not necessarily in one placeHow to store web resources efficiently in order to find them again
Further ChallengesNavigational disorientation
„lost in hyperspace“
Conceptual disorientationLack of integrating information in the own knowledge structure
Cognitive OverloadFinding information, analyzing found hits, organizing found information, …
See [SBB09+]
KOM – Multimedia Communications Lab 5
Challenges of Resource based Learning using Web Resources
Define Strategyfor Search Search
Select
PersistAnnotate
Share
Classificate
Use
KOM – Multimedia Communications Lab 6
Support of Resource based Learning
Define Strategyfor Search Search
Select
PersistAnnotate
Share
Classificate
Use
Linklists(Yahoo,…)
Searchengines(Google,…)
Expertsearch(Xing,…)
Ranking(Pagerank,…)
Rating Systems(StumbleUpon,…)
Tagg (Flickr, Del.icio.us,…)
Save as (Harddisk,…)
Browser Plugins
(Scrapbook,…)
Editors (Wikis, Excel,
Word,...)
Online-Annotation-Tools
(Diigo,…)
Social Bookmarking(Del.icio.us,…)
Electronic Communikation
(E-Mail,…)
Blogs (RSS,…)
KOM – Multimedia Communications Lab 7
Why a new application?
Using different applications add load to the user
Our scenario is characterized by:Heterogeneous resources
Text based formats like Wikis, FAQs, Blogs, PDF-DocumentsVideos Images...
Users are following individual tasks“Small” communityExisting applications do not fit for this characteristics in many casesGoal: CROKODIL: Support the user in the management of Web Resources using for Knowledge Acquisition
KOM – Multimedia Communications Lab 8
Outline
Scenario: Resource based Learning / Knowledge Acquisition
CROKODIL – a platform for collaborative Knowledge Acquisition based on Web Resources
Concept & Usage of Semantic NetworksFinding and Recommendation of Resources
Conclusion & Outlook
KOM – Multimedia Communications Lab 9
Semantic Networks
Used for knowledge representation
Formal modelConcepts(Semantic) Relations
Directed or undirected graph
Distinction usually in types and instances“Anne is a instance of the type person”
Challenge: How can be semantic information added effitiently?
Image source:http://www.tojet.net/articles/236.htm
KOM – Multimedia Communications Lab 10
Tagging
Simple mean to organize websites, bookmarks, pictures,…without constraints of strict classification
Folksonomic structures by aggregating tags of all users
Example: DeliciousSocial bookmarking application (saving, annotating, managing, sharing web pages)Tag suggestionsBrowsing via tagsNetworks between users
KOM – Multimedia Communications Lab 11
Concept – Semantic Tagging
Construction of a personal net of resources by semantic tagging
1 Annotation
2 Semantic Tagging3 Sharing with a community
Tag
Topic
Event
Person
Location
Goal/Task
related to
Photos
Blog
Script
NewsAvi
PaperWiki
Prepare Talk
TUD
TU Berlin
Workshop
Talk
Presenter
Hurricane
Lecture
ProfWind
to read
Tornado
eyewitness report
Blizzard
See [BSRS09] [BSR+]
KOM – Multimedia Communications Lab 12
CROKODIL - Persist
KOM – Multimedia Communications Lab 13
CROKODIL - Classificate / annotate
KOM – Multimedia Communications Lab 14
KOM – Multimedia Communications Lab 15
Outline
Scenario: Resource based Learning / Knowledge Acquisition
CROKODIL – a platform for collaborative Knowledge Acquisition based on Web Resources
Concept & Usage of Semantic NetworksFinding and Recommendation of Resources
Conclusion & Outlook
KOM – Multimedia Communications Lab 16
Finding Resources
By browsing the Semantic Network By browsing the CROKODIL Portal
KOM – Multimedia Communications Lab 17
Recommendations
Recommender systemsPresent information items to users that are likely of interestBased on implicit / explicit user profilesUse technologies from Information Retrieval
Different paradigms of generating / making recommendationsCollaborative Filtering
Based on similarity between users, good if there is enough dataOften so-called cold-start problem (not enough ratings available)
Content-based recommendationBased on properties or contents of resources
Recommendation based on folksonnomies and frequency of utilizationActive recommendation by users for:username
Amazon book and CD recommendations (Source: amazon.com)
Not applicable in small communities
& often biased results
Not applicable for heterogenous resources
Using a combination of different methods in CROKODIL
KOM – Multimedia Communications Lab 18
Structure based Recommendation in Semantic Networks
Recommending by traversing the Semantic Network
Recommendation independent of Type of Resources
Protocols
Communication Networks
paper script
WikiissubtopicRecommendation
KOM – Multimedia Communications Lab 19
Content-Based Recommendations
Similarity / relatedness between snippets is calcualted by comparision with Wikipedia articles
See [SBD+10]
?Protocols
Communication Networks
paperscript
Wiki
issubtopic
Computer Networks
WPWPWP
WPWPWP
Recommendation
KOM – Multimedia Communications Lab 20
Outline
Scenario: Resource based Learning / Knowledge Acquisition
CROKODIL – a platform for collaborative Knowledge Acquisition based on Web Resources
Concept & Usage of Semantic NetworksRecommending and Finding of Resources
Conclusion & Outlook
KOM – Multimedia Communications Lab 21
Conclusion & Outlook
CROKODILan social application for managing heterogeneous Web Resources used for Knowledge Acquisitionbased on a combination of semantic networks and taggingIntegrated recommender systems based on different methods
OutlookDeployment of the prototype in industry and universityLong term evaluation of the overall approach and the different methods for recommendationExtensions
Optimization of recommendation methodsRecommending tagsMerging personal knowledge networks
KOM – Multimedia Communications Lab 22
References
[SBB09+] Philipp Scholl, Bastian F. Benz, Doreen Böhnstedt, Christoph Rensing, Bernhard Schmitz, Ralf Steinmetz: Implementation and Evaluation of a Tool for Setting Goals in Self-Regulated Learning with Web Resources. In: Ulrike Cress, VaniaDimitrova, Marcus Specht: Learning in the Synergy of Multiple Disciplines, EC-TEL 2009, vol. LNCS Vol 5794, p. 521-534, Springer-Verlag Berlin Heidelberg, October 2009. ISBN 978-3-642-04635-3.
[BSRS09] Doreen Böhnstedt, Philipp Scholl, Christoph Rensing, Ralf Steinmetz: Modeling Personal Knowledge Networks to Support Resource Based Learning. In: Klaus Tochtermann, Hermann Maurer: Proceedings of 9th International Conference on Knowledge Management and Knowledge Technologies (I-KNOW'09), p. 309-316, September 2009. ISBN 978-3-85125-060-2.
[BSR+09] Doreen Böhnstedt, Philipp Scholl, Christoph Rensing, Ralf Steinmetz: Collaborative Semantic Tagging of Web Resources on the Basis of Individual Knowledge Networks. In: Houben, G.-J.; McCalla, G.; Pianesi, F.; Zancanaro, M.: Proceedings of First and Seventeenth International Conference on User Modeling, Adaptation, and Personalization UMAP 2009, p. 379-384, Springer-Verlag Berlin Heidelberg 2009, ISBN 978-3-642-02246-3.
[SBD+10] Philpp Scholl, Doreen Böhnestedt, Renato Dominguez-Garcia, ChristophRensing, Ralf Steinmetz: Extended Explicit Semantic Analysis for Calculating Semantic Relatedness of Web Resources. Accepted for publication in: Proceedings of the Fifth European Conference on Technology Enhanced Learning, Barcelona, September 2010.
KOM – Multimedia Communications Lab 23
This work was supported by funds from the German Federal Ministry of Education and Research under the mark 01 PF 08015 A and from the European Social Fund of the European Union (ESF).
KOM – Multimedia Communications Lab 24