Y. Ishikawa, Y. Chen, and H. Kitagawa, : "An On-Line Document Clustering Method Based on Forgetting Factors", Proc. 5th European Conference on Research and Advanced Technology for Digital Libraries (ECDL 2001), Vol. 2163 of Lecture Notes in Computer Science, pp. 325-339, Darmstadt, Germany, September 2001
S. M. Pahlevi and H. Kitagawa : "A Taxonomy-based Focused Retrieval Method for the Web Space", Proc. Pan-Yellow-Sea International Workshop on Information Technologies for Network Era (PYIWIT '02), pp. 127-134, Saga, Japan, March 2002
S. M. Pahlevi and H. Kitagawa : "Taxonomy-based Adaptive Web Search Method", Proc. 3rd IEEE International Conference on Information Technology: Coding and Computing (ITCC 2002), pp. 320-325, Las Vegas, April 2002
S. M. Pahlevi and H. Kitagawa : "TAX-PQ: Dynamic Taxonomy Probing and Query Modification for Topic-focused Web Search", Proc. 8th International Conference on Database Systems for Advanced Applications (DASFAA 2003), pp. 91-100, Kyoto, Japan, March 2003
S. M. Pahlevi and H. Kitagawa : "Taxonomy-based Context Conveyance for Web Search", Proc. 10th International Conference on Cooperative Information Systems (CoopIS 2003), pp. 536-553, Catania, Italy, November 2003
C. Cui and H. Kitagawa : "Topic Activation Analysis for Document Streams Based on Document Arrival Rate and Relevance", Proc. 20th Annual ACM Symposium on Applied Computing (SAC 2005), Vol. 2, pp. 1089-1095, March 2005
Proc. International Special Workshop on Databases for Next Generation Researchers (SWOD 2005), pp. 146-149 : "A Tool to Compute Reliable Web Links and Its Applications", A. Nakamizo, T. Iida, A. Morishima, S. Sugimoto, and H. Kitagawa, Tokyo, Japan, April 2005
J. Zhang, Y. Ishikawa and H. Kitagawa : "Extended Link Analysis for Extracting Spatial Information Hubs", Proc. International Workshop on Challenges in Web Information Retrieval and Integration (WIRI 2005), pp. 17-22, Tokyo, Japan, April 2005
for Text Streams : "A Comparative Study of Feature Vector-Based Topic Detection Schemes", M. Hamamoto, H. Kitagawa, J.-Y. Pan, and C. Faloutsos, Proc. International Workshop on Challenges in Web Information Retrieval and Integration (WIRI 2005), pp. 122-127, Tokyo, Japan
J. Zhang, Y. Ishikawa, S. Kurokawa, and H. Kitagawa : "LocalRank: Ranking Web Pages Considering Geographical Locality by Integrating Web and Databases", Proc. 16th International Conference on Database and Expert Systems Applications (DEXA 2005), LNCS 3588, pp. 145-155, Copenhagen, Denmark, August 2005