International Semantic Web Conference (ISWC) is the premier conference on semantic web research. The 8th conference in this series was held in 27th – 29th, October, 2009, at the Westfields Conference Center near Washington, DC. The main conference consists of about 80 oral presentations scheduled in 3 days, categorized into Research Track, Semantic Web In-Use Track, Doctoral Consortium Track, and Industry Track. There is also a poster session, a lightning talk session, and a Semantic Web Challenge session where new applications of semantic web datasets and technologies are showcased and entered into competition. Pat Hayes (Institute for Human and Machine Cognition), Tom Mitchell (Carnegie-Mellon University), and Nova Spivack (Radar Networks) gave three keynotes. The detailed program can be found at the ISWC 2009 conference website.

In addition to the main conference, ISWC 2009 also included tutorials and workshops, held on the 25th and 26th. As this is the first time I ever attended ISWC (or any semantic web conference), I took this opportunity to learn more from the following: How to Consume Linked Data on the Web (tutorial), Legal and Social Frameworks for Sharing Data on the Web (tutorial), Building Ontology-based Applications using Pellet (tutorial), and Terra Cognita (workshop). ISWC 2009 also co-located with other meetings. Among them, I was interested in the 6th OWL Experiences and Directions Workshop (23rd – 24th), the 3rd International Conference on Web Reasoning and Rule Systems (25th – 26th), and the Semantic Web and Museum Data Workshop (25th), but did not attend any of them because of time constraint. The ISWC 2009 website has links to all tutorials, workshops, and co-located meetings.

Given the many attractions in ISWC 2009, I can only say about a few that interested me. Tom Mitchell's keynote shows how ontologies (even the simple ones) help structuring information machine-mined from large collections of web pages, and how the extracted data helps refining the human-given ontologies. This model of mutual enrichment, though only on special knowledge domains and not entirely automatic, seems to work well and warrants further investigation. Erétéo, Buffa, Gandon, and Corby give a nice presentation on using semantic web technologies for the analyses of online social networks. Auer, Lehmann, and Hellmann show how to add a spatial dimension to the web of linked data by elevating information from the community built OpenStreetMap datasets. I also find Bernhard Schandl's presentation on Functions over RDF Language Elements interesting (perhaps because of my background in functional programming).

One of the objectives for me to attend ISWC 2009 is to learn "in the field" about ontologies especially about how they are used, in practice, in semantic web applications. To this end, I get some understanding of this area from the following presentations: OntoCase — Automatic Ontology Enrichment Based on Ontology Design Patterns (Eva Blomqvist), What Four Million Mappings Can Tell You About Two Hundred Ontologies (Ghazvinian, Noy, Jonquet, Shah, and Musen), and Exploiting Partial Information in Taxonomy Construction (Shearer and Horrocks).

My personal favorites, however, are the following three presentations: Produce and Consume Linked Data with Drupal! by Stéphane Corlosquet et. al., which also receives the best paper in the Semantic Web In-Use Track, What's New for SPARQL? which is a panel organized by the W3C SPARQL Working Group, and Linked Data and The New York Times by Evan Sandhaus. In my view, these are nice examples of the maturity of (and the need for continuous improvement to) the tools, languages, and applications of the semantic web research.

Over all, ISWC 2009 is a great event to sample the state of the art in semantic web research and development. My impression is that people from different backgrounds are congregating to the semantic web area. For example, you see people working on description logic, on rule and reasoning, on ontology, on information retrieval and web mining, on linking open data on the web, and on web standardization and engineering. There is a significant presence of European research networks (e.g., DBpedia, LarKC, and NeON); one can also easily sense the intense interest from the industries (especially from the US defense industry). It has been a large crowd of interesting people.

Chantilly, Virginia, USA.
Chantilly, Virginia, USA.

Note: Obligatory trip report, submitted to Academia Sinica in December 2009.