Conference Paper

Discovery of Environmental Web Resources Based on the Combination of Multimedia Evidence

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Abstract

This work proposes a framework for the discovery of environmental Web resources providing air quality measurements and forecasts. Motivated by the frequent occurrence of heatmaps in such Web resources, it exploits multimedia evidence at different stages of the discovery process. Domain-specific queries generated using empirical information and machine learning driven query expansion are submitted both to the Web and Image search services of a general-purpose search engine. Post-retrieval filtering is performed by combining textual and visual (heatmap-related) evidence in a supervised machine learning framework. Our experimental results indicate improvements in the effectiveness when performing heatmap recognition based on SURF and SIFT descriptors using VLAD encoding and when combining multimedia evidence in the discovery process.

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. Domain-specic internet portals are growing in popularity because they gather content from the Web and organize it for easy access, retrieval and search. For example, www.campsearch.com allows complex queries by age, location, cost and specialty over summer camps. This functionality is not possible with general, Web-wide search engines. Unfortunately these portals are dicult and time-consuming to maintain. This paper advocates the use of machine learning techniques to greatly automate the creation and maintenance of domain-specic Internet portals. We describe new research in reinforcement learning, information extraction and text classication that enables ecient spidering, the identication of informative text segments, and the population of topic hierarchies. Using these techniques, we have built a demonstration system: a portal for computer science research papers. It already contains over 50,000 papers and is publicly available at www.cora.justresearch.com. These techniques are ...
TRECVID 2007-overview
  • P Over
  • G Awad
  • W Kraaij
  • A F Smeaton
P. Over, G. Awad, W. Kraaij, and A. F. Smeaton. TRECVID 2007-overview. In TRECVID 2007 workshop participants notebook papers, 2007.