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, Canada2

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, Canada3

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, Canada4

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, Canada5

6. Linking Blogs and Ontology SAAKM 2007, Whistler, Canada6 Blog entries Ontology Semantic Annotation

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, Canada7

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, Canada8

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, Canada9

10. Application Scenario SAAKM 2007, Whistler, Canada10

11. System Architecture SAAKM 2007, Whistler, Canada11

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, Canada12

13. Example Ontology SAAKM 2007, Whistler, Canada13

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, Canada14

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, Canada15

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, Canada16

17. SAAKM 2007, Whistler, Canada17 Authoring Blog Entry Next…

18. Suggestions for semantic annotation SAAKM 2007, Whistler, Canada18

19. Blog-Ontology Linking SAAKM 2007, Whistler, Canada19

20. Blog-Ontology Linking SAAKM 2007, Whistler, Canada20 Instances in Ontology Blog Entries

21. Semantic Navigation SAAKM 2007, Whistler, Canada21

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, Canada22

23. Semantic Aggregation Collect and organize search results relevant to a topic of interest Algorithm 1.Get all relevant blog entries from search 2.Find the set of instances linked to each blog entry 3.Find all relations between the instances 4.Visualize the related instances as directed graphs GraphML used SAAKM 2007, Whistler, Canada23

24. Semantic Aggregation SAAKM 2007, Whistler, Canada24 Search results Related Entries click

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, Canada25

26. Feedback form for suggesting new Concepts/Instances SAAKM 2007, Whistler, Canada26

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, Canada27

28. Semantic Search Results SAAKM 2007, Whistler, Canada28

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, Canada29

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, Canada30

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, Canada31

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, Canada32

33. Thank you ! Questions / Suggestions SAAKM 2007, Whistler, Canada33