| 2025 | SISAP | Double Filtering Using Short and Long Quantized Projections. | Naoya Higuchi, Yasunobu Imamura, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2024 | ICPRAM | Fast Filtering for Similarity Search Using Conjunctive Enumeration of Sketches in Order of Hamming Distance. | Naoya Higuchi, Yasunobu Imamura, Vladimir Mic, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2024 | ICPRAM | Fast Filtering by Conjunctive Enumeration of Sketches for Nearest Neighbor Search. | Naoya Higuchi, Yasunobu Imamura, Vladimir Mic, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2023 | ICPRAM | Subcaterpillar Isomorphism Between Caterpillars: Subtree Isomorphism Restricted Text and Pattern Trees to Caterpillars. | Tomoya Miyazaki, Kouichi Hirata |
| 2023 | ICPRAM | Correlated Mutations of Positions Among Structural Proteins in Delta and Omicron Variants for SARS-CoV-2 Amino Acid Sequences. | Yuichi Shimaya, Kouichi Hirata |
| 2022 | FedCSIS | Subcaterpillar Isomorphism: Subtree Isomorphism Restricted Pattern Trees To Caterpillars. | Tomoya Miyazaki, Kouichi Hirata |
| 2022 | ICPRAM | Computing the Variations of Edit Distance for Rooted Labaled Caterpillars. | Manami Hagihara, Takuya Yoshino, Kouichi Hirata |
| 2022 | ICPRAM | Nearest-neighbor Search from Large Datasets using Narrow Sketches. | Naoya Higuchi, Yasunobu Imamura, Vladimir Mic, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2022 | ICPRAM | Caterpillar Inclusion: Inclusion Problem for Rooted Labeled Caterpillars. | Tomoya Miyazaki, Manami Hagihara, Kouichi Hirata |
| 2022 | ICPRAM | Object Detection as Campylobacter Bacteria and Phagocytotic Activity of Leukocytes in Gram Stained Smears Images. | Kyohei Yoshihara, Kouichi Hirata |
| 2022 | WCO | Subcaterpillar Isomorphism: Subtree Isomorphism for Rooted Labeled Caterpillars. | Tomoya Miyazaki, Kouichi Hirata |
| 2020 | ICPRAM | Heavy Caterpillar Distances for Rooted Labeled Unordered Trees. | Nozomi Abe, Takuya Yoshino, Kouichi Hirata |
| 2020 | ICPRAM | Detecting Geckler Classification from Gram Stained Smears Images for Sputum. | Kazuki Hashimoto, Ryosuke Iida, Kouichi Hirata, Kimiko Matsuoka, Shigeki Yokoyama |
| 2020 | ICPRAM | Detection System of Gram Types for Bacteria from Gram Stained Smears Images. | Ryosuke Iida, Kazuki Hashimoto, Kouichi Hirata, Kimiko Matsuoka, Shigeki Yokoyama |
| 2020 | SISAP | Pivot Selection for Narrow Sketches by Optimization Algorithms. | Naoya Higuchi, Yasunobu Imamura, Vladimir Mic, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2019 | FedCSIS | Alignment for Rooted Labeled Caterpillars. | Yoshiyuki Ukita, Takuya Yoshino, Kouichi Hirata |
| 2019 | ICPRAM | Fast Nearest Neighbor Search with Narrow 16-bit Sketch. | Naoya Higuchi, Yasunobu Imamura, Tetsuji Kuboyama, Kouichi Hirata, Takeshi Shinohara |
| 2019 | ICPRAM | Annealing by Increasing Resampling. | Naoya Higuchi, Yasunobu Imamura, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2019 | ICPRAM | Annealing by Increasing Resampling in the Unified View of Simulated Annealing. | Yasunobu Imamura, Naoya Higuchi, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2019 | ICPRAM | Bipartite Edge Correlation Clustering: Finding an Edge Biclique Partition from a Bipartite Graph with Minimum Disagreement. | Mikio Mizukami, Kouichi Hirata, Tetsuji Kuboyama |
| 2019 | ICPRAM | Vertical and Horizontal Distances to Approximate Edit Distance for Rooted Labeled Caterpillars. | Kohei Muraka, Takuya Yoshino, Kouichi Hirata |
| 2019 | TAMC | Introducing Fluctuation into Increasing Order of Symmetric Uncertainty for Consistency-Based Feature Selection. | Sho Shimamura, Kouichi Hirata |
| 2018 | ACIIDS | Path Histogram Distance for Rooted Labeled Caterpillars. | Taiga Kawaguchi, Takuya Yoshino, Kouichi Hirata |
| 2018 | FedCSIS | Computing Edit Distance between Rooted Labeled Caterpillars. | Kohei Muraka, Takuya Yoshino, Kouichi Hirata |
| 2018 | IC3K | LCA Histogram Distance for Rooted Labeled Caterpillars. | Takuya Yoshino, Kohei Muraka, Kouichi Hirata |
| 2018 | ICPRAM | Nearest Neighbor Search using Sketches as Quantized Images of Dimension Reduction. | Naoya Higuchi, Yasunobu Imamura, Tetsuji Kuboyama, Kouichi Hirata, Takeshi Shinohara |
| 2018 | ICPRAM | Earth Mover's Distances for Rooted Labaled Unordered Trees based on Tai Mapping Hierarchy. | Taiga Kawaguchi, Kouichi Hirata |
| 2018 | ICPRAM | Earth Mover's Distance Between Rooted Labeled Unordered Trees Formulated from Complete Subtrees. | Taiga Kawaguchi, Takuya Yoshino, Kouichi Hirata |
| 2017 | DIS | Extracting Mutually Dependent Multisets. | Natsuki Kiyota, Sho Shimamura, Kouichi Hirata |
| 2017 | FedCSIS | Anchored Alignment Distance between Rooted Labeled Unordered Trees. | Kouichi Hirata, Takuya Yoshino, Yuma Ishizaka |
| 2016 | SISAP | Fast Hilbert Sort Algorithm Without Using Hilbert Indices. | Yasunobu Imamura, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2015 | ICPRAM | Classifying Nucleotide Sequences and their Positions of Influenza A Viruses through Several Kernels. | Issei Hamada, Takaharu Shimada, Daiki Nakata, Kouichi Hirata, Tetsuji Kuboyama |
| 2015 | ICPRAM | High Dimensional Similarity Search with Bundled Query Processing on Hilbert R-Tree. | Yohei Nasu, Naoki Kishikawa, Kei Tashima, Shin Kodama, Yasunobu Imamura, Takeshi Shinohara, Kouichi Hirata, Tetsuji Kuboyama |
| 2015 | ICPRAM | Alignment of Cyclically Ordered Trees. | Takuya Yoshino, Kouichi Hirata |
| 2013 | DIS | Polynomial Delay and Space Discovery of Connected and Acyclic Sub-hypergraphs in a Hypergraph. | Kunihiro Wasa, Takeaki Uno, Kouichi Hirata, Hiroki Arimura |
| 2013 | PERCOM | Exploring social context from buzz marketing site - Community mapping based on tree edit distance -. | Shoichi Higuchi, Tetsuji Kuboyama, Takako Hashimoto, Kouichi Hirata |
| 2013 | SISAP | Faster Algorithms for Tree Similarity Based on Compressed Enumeration of Bounded-Sized Ordered Subtrees. | Kunihiro Wasa, Kouichi Hirata, Takeaki Uno, Hiroki Arimura |
| 2012 | DIS | A Trim Distance between Positions in Nucleotide Sequences. | Shunsuke Makino, Takaharu Shimada, Kouichi Hirata, Kouki Yonezawa, Kimihito Ito |
| 2012 | ISAAC | Segmental Mapping and Distance for Rooted Labeled Ordered Trees. | Tomohiro Kan, Shoichi Higuchi, Kouichi Hirata |
| 2011 | CPM | Improved MAX SNP-Hard Results for Finding an Edit Distance between Unordered Trees. | Kouichi Hirata, Yoshiyuki Yamamoto, Tetsuji Kuboyama |
| 2009 | DIS | Mining Frequent Bipartite Episode from Event Sequences. | Takashi Katoh, Hiroki Arimura, Kouichi Hirata |
| 2009 | KES | Discovering Networks for Global Propagation of Influenza A (H3N2) Viruses by Clustering. | Kazuya Sata, Kouichi Hirata, Kimihito Ito, Tetsuji Kuboyama |
| 2009 | PAKDD | A Polynomial-Delay Polynomial-Space Algorithm for Extracting Frequent Diamond Episodes from Event Sequences. | Takashi Katoh, Hiroki Arimura, Kouichi Hirata |
| 2009 | SOFSEM | Approximating Tree Edit Distance through String Edit Distance for Binary Tree Codes. | Taku Aratsu, Kouichi Hirata, Tetsuji Kuboyama |
| 2009 | SOFSEM | On Generating All Maximal Acyclic Subhypergraphs with Polynomial Delay. | Taishin Daigo, Kouichi Hirata |
| 2008 | PAKDD | Sibling Distance for Rooted Labeled Trees. | Taku Aratsu, Kouichi Hirata, Tetsuji Kuboyama |
| 2008 | PAKDD | A Simple Characterization on Serially Constructible Episodes. | Takashi Katoh, Kouichi Hirata |
| 2008 | PAKDD | An Efficient Unordered Tree Kernel and Its Application to Glycan Classification. | Tetsuji Kuboyama, Kouichi Hirata, Kiyoko F. Aoki-Kinoshita |
| 2008 | PAKDD | A Tree Distance Function Based on Multi-sets. | Arnoldo Jos Mller Molina, Kouichi Hirata, Takeshi Shinohara |
| 2007 | MDAI | Mining Frequent Diamond Episodes from Event Sequences. | Takashi Katoh, Kouichi Hirata, Masateru Harao |
| 2006 | DIS | Mining Sectorial Episodes from Event Sequences. | Takashi Katoh, Kouichi Hirata, Masateru Harao |
| 2005 | DIS | The | Nobuhito Ohkura, Kouichi Hirata, Tetsuji Kuboyama, Masateru Harao |
| 2005 | FCT | On Finding Acyclic Subhypergraphs. | Kouichi Hirata, Megumi Kuwabara, Masateru Harao |
| 2005 | ICITA | Multi-Agent Based Modeling and Simulation of Consensus Formations in Arguments. | Kosuke Ono, Masateru Harao, Kouichi Hirata |
| 2005 | ICITA | Performance Analysis for Construction of a Performance Practice Support System. | Shogo Ozaki, Masateru Harao, Kouichi Hirata |
| 2005 | PAKDD | Extraction of Frequent Few-Overlapped Monotone DNF Formulas with Depth-First Pruning. | Yoshikazu Shima, Kouichi Hirata, Masateru Harao |
| 2004 | DIS | Extracting Minimal and Closed Monotone DNF Formulas. | Yoshikazu Shima, Shinji Mitsuishi, Kouichi Hirata, Masateru Harao |
| 2004 | ILP | Generalization Algorithms for Second-Order Terms. | Kouichi Hirata, Takeshi Ogawa, Masateru Harao |
| 2003 | DIS | Extraction of Coverings as Monotone DNF Formulas. | Kouichi Hirata, Ryosuke Nagazumi, Masateru Harao |
| 2003 | ILP | On Condensation of a Clause. | Kouichi Hirata |
| 2001 | FCT | Prediction-Preserving Reducibility with Membership Queries on Formal Languages. | Kouichi Hirata, Hiroshi Sakamoto |
| 2000 | ALT | On the Hardness of Learning Acyclic Conjunctive Queries. | Kouichi Hirata |
| 1999 | ALT | Flattening and Implication. | Kouichi Hirata |
| 1999 | COCOON | Tractable and Intractable Second-Order Matching Problems. | Kouichi Hirata, Keizo Yamada, Masateru Harao |
| 1996 | ALT | Constructive Learning of Translations Based on Dictionaries. | Noriko Sugimoto, Kouichi Hirata, Hiroki Ishizaka |
| 1994 | ALT | Rule-Generating Abduction for Recursive Prolog. | Kouichi Hirata |