OntoBlog: Linking Ontology and Blogs

1. OntoBlog: Linking Ontology and Blogs Aman Shakya 1, Vilas Wuwongse 2, Hideaki Takeda 1, Ikki Ohmukai 1 1 National Institute of Informatics, Japan 2 Asian Institute of Technology, Thailand SAAKM 2007, Whistler, Canada

2. Contents • Background • Semantic Blogging • Semantic Annotation • Semantic Blogging as Semantic Annotation • The OntoBlog platform • Application Scenario • Implementation • Some experiences • Related Work • Conclusions and Future Work SAAKM 2007, Whistler, Canada

3. Background • Blogging • Publicly accessible web-based publication of periodic articles usually in reverse chronological order • Easy authoring platform • Unstructured • Filtering, organizing, navigating is difficult • Semantic Blogging • Provides semantic structure to blog items • Enrich blog entries with metadata • Combine features of Blogging and the Semantic Web • Informal knowledge management SAAKM 2007, Whistler, Canada

4. Semantic Annotation • Annotation • comments, notes, explanations or remarks attached to any document or a selected part of the document • Semantic Annotation • Annotation that references an Ontology • Identifies concepts and relations in documents • Intended for machines • Significance of semantic annotation • Enhanced information retrieval • Improved interoperability (Uren et al. , 2006) SAAKM 2007, Whistler, Canada

5. Semantic Blogging as Semantic Annotation • Semantic blogging may be viewed as semantic annotation to blog entries • Link blog entries to pre-existing Ontology and instances SAAKM 2007, Whistler, Canada

6. Linking Blogs and Ontology Semantic Annotation Blog entries Ontology SAAKM 2007, Whistler, Canada

7. Semantic Blogging as Semantic Annotation (contd..) • Rich semantic structure of ontology can enable useful semantic capabilities • Semantic annotation can help to • Retrieve relevant resources • Navigate meaningfully • Categorize and organize contents SAAKM 2007, Whistler, Canada

8. Semantic Annotation in Blogs • Blog entries are self-contained snippets or small contents • Blogs are used as easy platform for frequent personal publishing • Considerations for semantic annotation • Integrated authoring environment • Automation • Integrated services SAAKM 2007, Whistler, Canada

9. The OntoBlog Platform • Semantic Annotation • Annotate blog entries with existing ontology instances • Integrated Authoring • Authoring and annotation of blog entries • Semi-automatic Annotation • Suggest related instances automatically • Integrated Services • Semantic navigation, search and organization • Feedback for Ontology Maintenance • Suggest new concepts and instances Online demo - http://dutar.ex.nii.ac.jp/ontoblog/blog/default/ SAAKM 2007, Whistler, Canada

10. Application Scenario SAAKM 2007, Whistler, Canada

11. System Architecture SAAKM 2007, Whistler, Canada

12. Publishing Metadata • Blog entries may have content metadata • E.g., SWRC metadata for bibliography • Stored as RDF triplets • Metadata is exported in RSS feeds Ontology • Example ontology • Computer science department ontology • Based on SHOE computer department ontology • Populated and maintained using Protégé SAAKM 2007, Whistler, Canada

13. Example Ontology SAAKM 2007, Whistler, Canada

14. Inference • for_course has_topic • is_broader_thanis_narrower_than • teachestaught_by • Inverse relations • has_prerequisite , is_broader_than • Transitive relations • Used OWL Micro reasoner from Jena SAAKM 2007, Whistler, Canada

15. Blog-Ontology Linking • Link Blogging  existing Ontology system • using Semi-Automatic Semantic Annotation • Manual annotation • Cumbersome and error-prone • May depend on willingness of users • Authenticity and quality not guaranteed • Annotation can be automated by simple language processing techniques • can be very fast and quite effective SAAKM 2007, Whistler, Canada

16. Blog-Ontology Linking • Each concept has a “keywords” element • For each instance, the “keywords” element contains a collection of related words • Stemmed blog entries matched against stemmed “keywords” to discover related instances • Porter Stemming • Related instances automatically suggested when adding/updating blog entries • Discovered relations stored as related-to property (if the user approves) SAAKM 2007, Whistler, Canada

17. Authoring Blog Entry Next… SAAKM 2007, Whistler, Canada

18. Suggestions for semantic annotation SAAKM 2007, Whistler, Canada

19. Blog-Ontology Linking SAAKM 2007, Whistler, Canada

20. Blog-Ontology Linking Instances in Ontology Blog Entries SAAKM 2007, Whistler, Canada

21. Semantic Navigation SAAKM 2007, Whistler, Canada

22. Semantic Search • Simple implementation just to demonstrate applicability of semantic search • Augment traditional search results • Return blog entries linked to semantically related instances • Useful when text search alone does not produce enough results • Depth of semantic search can be controlled • Semantic search can be enabled or disabled SAAKM 2007, Whistler, Canada

23. Semantic Aggregation • Collect and organize search results relevant to a topic of interest Algorithm • Get all relevant blog entries from search • Find the set of instances linked to each blog entry • Find all relations between the instances • Visualize the related instances as directed graphs • GraphML used SAAKM 2007, Whistler, Canada

24. Semantic Aggregation Search results Related Entries click SAAKM 2007, Whistler, Canada

25. Feedback for Ontology Maintenance • If related instances or concepts are not present in the Knowledge Base • users may suggest a suitable instance and/or concept • Provides web-based form for new suggestions along with the automatic suggestions • Feedback from users is useful for the administrator/knowledge engineer to maintain the ontology • by adding missing concepts and instances or refining them SAAKM 2007, Whistler, Canada

26. Feedback form for suggesting new Concepts/Instances SAAKM 2007, Whistler, Canada

27. Some Experiences • Simple test experiments • About 100 dummy blog entries related to different courses, topics, researches, etc populated manually • 10 students from the Computer Science department of the Asian Institute of Technology helped in the tests • Automatic blog-ontology linking • 84% right suggestions SAAKM 2007, Whistler, Canada

28. Semantic Search Results SAAKM 2007, Whistler, Canada

29. Some Experiences • User Feedback • Many features are subjective and difficult to evaluate by experiments • Positive user response for most of the features • Not easy to judge relevance of semantic search results SAAKM 2007, Whistler, Canada

30. Related Work • Semantic Blogging • Semantic Blogging Demonstrator (HP labs) • Semantic Blogging using Haystack (Karger & Quan) • Semblog (Ohmukai & Takeda) • semiBlog (Möller et al.) (now renamed “Shift”) • SocioBiblog (Shakya et al.) • Semantic Annotation • semi-automatic semantic annotation – S-CREAM, extraction ontologies, etc • Magpie • Mangrove • KIM SAAKM 2007, Whistler, Canada

31. Conclusions • Linking Blogging and Ontology management technologies • OntoBlog – Semantic Blogging prototype • Semi-automatic annotation of blog entries with existing instances of an Ontology • Integrated platform • semantic authoring, annotation and information utilization • Semantic structure of ontology can enable semantic capabilities Navigation and Search in blogs • Feedback for ontology maintenance through blogging SAAKM 2007, Whistler, Canada

32. Future Work • Decentralized collaborative approach for Ontology • Folksonomy, Semantic Wiki, etc • Semantic capabilities across multiple blogs • Enhance inference capabilities • Incorporate mature semantic search • Ranked information retrieval • Sophisticated language processing • WordNet, IE (with supervised/unsupervised learning) • Support semantic blogging clients like semiBlog SAAKM 2007, Whistler, Canada

33. Thank you ! • Questions / Suggestions SAAKM 2007, Whistler, Canada