A classification of abduction: abduction for logic programming. - Kouichi Hirata (Machine Intelligence 14, 1993)

Rule-Generating Abduction for Recursive Prolog. - Kouichi Hirata (AII/ALT, 1994)

Constructive Learning of Translations Based on Dictionaries. - Noriko Sugimoto; Kouichi Hirata; Hiroki Ishizaka (ALT, 1996)

On the Hardness of Approximating the Minimum Consistent OBDD Problem. - Kouichi Hirata; Shinichi Shimozono; Ayumi Shinohara (SWAT, 1996)

Constructing Simply Recursive Programs from a Finite Set of Good Examples. - Kouichi Hirata (Inf. Process. Lett., 1997)

On the Hardness of Approximating the minimum Consistent Acyclic DFA and Decision Diagram. - Shinichi Shimozono; Kouichi Hirata; Ayumi Shinohara (Inf. Process. Lett., 1998)

Flattening and Implication. - Kouichi Hirata (ALT, 1999)

Tractable and Intractable Second-Order Matching Problems. - Kouichi Hirata; Keizo Yamada; Masateru Harao (COCOON, 1999)

On the Hardness of Learning Acyclic Conjunctive Queries. - Kouichi Hirata (ALT, 2000)

Constructive Learning of Context-Free Languages with a Subpansive Tree. - Noriko Sugimoto; Takashi Toyoshima; Shinichi Shimozono; Kouichi Hirata (ICGI, 2000)

Prediction-Preserving Reducibility with Membership Queries on Formal Languages. - Kouichi Hirata; Hiroshi Sakamoto (FCT, 2001)

Extraction of Coverings as Monotone DNF Formulas. - Kouichi Hirata; Ryosuke Nagazumi; Masateru Harao (Discovery Science, 2003)

On Condensation of a Clause. - Kouichi Hirata (ILP, 2003)

Learning elementary formal systems with queries. - Hiroshi Sakamoto; Kouichi Hirata; Hiroki Arimura (Theor. Comput. Sci., 2003)

Extracting Minimal and Closed Monotone DNF Formulas. - Yoshikazu Shima; Shinji Mitsuishi; Kouichi Hirata; Masateru Harao (Discovery Science, 2004)

Generalization Algorithms for Second-Order Terms. - Kouichi Hirata; Takeshi Ogawa; Masateru Harao (ILP, 2004)

The q-Gram Distance for Ordered Unlabeled Trees. - Nobuhito Ohkura; Kouichi Hirata; Tetsuji Kuboyama; Masateru Harao (Discovery Science, 2005)

On Finding Acyclic Subhypergraphs. - Kouichi Hirata; Megumi Kuwabara; Masateru Harao (FCT, 2005)

Multi-Agent Based Modeling and Simulation of Consensus Formations in Arguments. - Kosuke Ono; Masateru Harao; Kouichi Hirata (ICITA (1), 2005)

Performance Analysis for Construction of a Performance Practice Support System. - Shogo Ozaki; Masateru Harao; Kouichi Hirata (ICITA (2), 2005)

Prediction of Recursive Real-Valued Functions from Finite Examples. - Eiju Hirowatari; Kouichi Hirata; Tetsuhiro Miyahara (JSAI Workshops, 2005)

On Generalization and Subsumption for Ordered Clauses. - Megumi Kuwabara; Takeshi Ogawa; Kouichi Hirata; Masateru Harao (JSAI Workshops, 2005)

Development of a Multi-Agent Based Generic Traffic Simulator. - Kosuke Ono; Takashi Hata; Toyofumi Maetani; Masateru Harao; Kouichi Hirata (JSAI Workshops, 2005)

Workshop on Learning with Logics and Logics for Learning (LLLL). - Akihiro Yamamoto; Kouichi Hirata (JSAI Workshops, 2005)

Extraction of Frequent Few-Overlapped Monotone DNF Formulas with Depth-First Pruning. - Yoshikazu Shima; Kouichi Hirata; Masateru Harao (PAKDD, 2005)

Prediction-hardness of acyclic conjunctive queries. - Kouichi Hirata (Theor. Comput. Sci., 2005)

Mining Sectorial Episodes from Event Sequences. - Takashi Katoh; Kouichi Hirata; Masateru Harao (Discovery Science, 2006)

The Fourth Workshop on Learning with Logics and Logics for Learning (LLLL2006). - Akihiro Yamamoto; Kouichi Hirata; Ken Satoh (JSAI, 2006)

Refutability and Reliability for Inductive Inference of Recursive Real-Valued Functions. - Eiju Hirowatari; Kouichi Hirata; Tetsuhiro Miyahara; Setsuo Arikawa (Inf. Media Technol., 2006)

The Fifth Workshop on Learning with Logics and Logics for Learning (LLLL2007). - Akihiro Yamamoto; Kouichi Hirata (JSAI, 2007)

Mining Frequent Diamond Episodes from Event Sequences. - Takashi Katoh; Kouichi Hirata; Masateru Harao (MDAI, 2007)

A Spectrum Tree Kernel. - Tetsuji Kuboyama; Kouichi Hirata; Hisashi Kashima; Kiyoko F. Aoki-Kinoshita; Hiroshi Yasuda (Inf. Media Technol., 2007)

Efficient schema matching algorithm based on pre-checking. - Kengo Kubo; Keizo Yamada; Kouichi Hirata; Masateru Harao (Syst. Comput. Jpn., 2007)

Sibling Distance for Rooted Labeled Trees. - Taku Aratsu; Kouichi Hirata; Tetsuji Kuboyama (PAKDD Workshops, 2008)

A Simple Characterization on Serially Constructible Episodes. - Takashi Katoh; Kouichi Hirata (PAKDD, 2008)

An Efficient Unordered Tree Kernel and Its Application to Glycan Classification. - Tetsuji Kuboyama; Kouichi Hirata; Kiyoko F. Aoki-Kinoshita (PAKDD, 2008)

A Tree Distance Function Based on Multi-sets. - Arnoldo José Müller Molina; Kouichi Hirata; Takeshi Shinohara (PAKDD Workshops, 2008)

Mining Frequent Bipartite Episode from Event Sequences. - Takashi Katoh; Hiroki Arimura; Kouichi Hirata (Discovery Science, 2009)

Mining Frequent k-Partite Episodes from Event Sequences. - Takashi Katoh; Hiroki Arimura; Kouichi Hirata (JSAI-isAI Workshops, 2009)

The Sixth Workshop on Learning with Logics and Logics for Learning (LLLL2009). - Akihiro Yamamoto; Kouichi Hirata; Shin-ichi Minato (JSAI-isAI Workshops, 2009)

Discovering Networks for Global Propagation of Influenza A (H3N2) Viruses by Clustering. - Kazuya Sata; Kouichi Hirata; Kimihito Ito; Tetsuji Kuboyama (KES (2), 2009)

A Polynomial-Delay Polynomial-Space Algorithm for Extracting Frequent Diamond Episodes from Event Sequences. - Takashi Katoh; Hiroki Arimura; Kouichi Hirata (PAKDD, 2009)

Approximating Tree Edit Distance through String Edit Distance for Binary Tree Codes. - Taku Aratsu; Kouichi Hirata; Tetsuji Kuboyama (SOFSEM, 2009)

On Generating All Maximal Acyclic Subhypergraphs with Polynomial Delay. - Taishin Daigo; Kouichi Hirata (SOFSEM, 2009)

An Efficient Depth-first Search Algorithm for Extracting Frequent Diamond Episodes from Event Sequences. - Takashi Katoh; Hiroki Arimura; Kouichi Hirata (Inf. Media Technol., 2010)

Improved MAX SNP-Hard Results for Finding an Edit Distance between Unordered Trees. - Kouichi Hirata; Yoshiyuki Yamamoto; Tetsuji Kuboyama (CPM, 2011)

An A* Algorithm for Computing Edit Distance between Rooted Labeled Unordered Trees. - Shoichi Higuchi; Tomohiro Kan; Yoshiyuki Yamamoto; Kouichi Hirata (JSAI-isAI Workshops, 2011)

On Computing Tractable Variations of Unordered Tree Edit Distance with Network Algorithms. - Yoshiyuki Yamamoto; Kouichi Hirata; Tetsuji Kuboyama (JSAI-isAI Workshops, 2011)

A Trim Distance between Positions in Nucleotide Sequences. - Shunsuke Makino; Takaharu Shimada; Kouichi Hirata; Kouki Yonezawa; Kimihito Ito (Discovery Science, 2012)

An Isolated-Subtree Inclusion for Unordered Trees. - Takahiro Hokazono; Tomohiro Kan; Yoshiyuki Yamamoto; Kouichi Hirata (IIAI-AAI, 2012)

Translating XML Documents Through Dyck-Typed Regular Translation Elementary Formal Systems. - Noriko Sugimoto; Kouichi Hirata (IIAI-AAI, 2012)

Segmental Mapping and Distance for Rooted Labeled Ordered Trees. - Tomohiro Kan; Shoichi Higuchi; Kouichi Hirata (ISAAC, 2012)

A trim distance between positions as packaging signals in H3N2 influenza viruses. - Shunsuke Makino; Takaharu Shimada; Kouichi Hirata; Kouki Yonezawa; Kimihito Ito (SCIS&ISIS, 2012)

Finding correlated mutations among RNA segments in H3N2 influenza viruses. - Takaharu Shimada; Tatsuya Hazemoto; Shunsuke Makino; Kouichi Hirata; Kimihito Ito (SCIS&ISIS, 2012)

Polynomial Delay and Space Discovery of Connected and Acyclic Sub-hypergraphs in a Hypergraph. - Kunihiro Wasa; Takeaki Uno; Kouichi Hirata; Hiroki Arimura (Discovery Science, 2013)

Development of Flexible User Need's Investigation System Based on XML Conversions. - Masao Hattori; Keiichi Matsumoto; Noriko Sugimoto; Alireza Ahrary; Kouichi Hirata (IIAI-AAI, 2013)

Clustering of Positions in Nucleotide Sequences by Trim Distance. - Takaharu Shimada; Issei Hamada; Kouichi Hirata; Tetsuji Kuboyama; Kouki Yonezawa; Kimihito Ito (IIAI-AAI, 2013)

A Dynamic Programming A* Algorithm for Computing Unordered Tree Edit Distance. - Takuya Yoshino; Shoichi Higuchi; Kouichi Hirata (IIAI-AAI, 2013)

Agreement Subtree Mapping Kernel for Phylogenetic Trees. - Issei Hamada; Takaharu Shimada; Daiki Nakata; Kouichi Hirata; Tetsuji Kuboyama (JSAI-isAI Workshops, 2013)

Exploring social context from buzz marketing site - Community mapping based on tree edit distance -. - Shoichi Higuchi; Tetsuji Kuboyama; Takako Hashimoto; Kouichi Hirata (PerCom Workshops, 2013)

Faster Algorithms for Tree Similarity Based on Compressed Enumeration of Bounded-Sized Ordered Subtrees. - Kunihiro Wasa; Kouichi Hirata; Takeaki Uno; Hiroki Arimura (SISAP, 2013)

Mapping Kernels Between Rooted Labeled Trees Beyond Ordered Trees. - Kouichi Hirata; Tetsuji Kuboyama; Takuya Yoshino (JSAI-isAI Workshops, 2014)

Anchored Alignment Problem for Rooted Labeled Trees. - Yuma Ishizaka; Takuya Yoshino; Kouichi Hirata (JSAI-isAI Workshops, 2014)

Central Point Selection in Dimension Reduction Projection Simple-Map with Binary Quantization. - Quming Jin; Masaya Nakashima; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (JSAI-isAI Workshops, 2014)

Tractable and Intractable variations of Unordered Tree Edit Distance. - Yoshiyuki Yamamoto; Kouichi Hirata; Tetsuji Kuboyama (Int. J. Found. Comput. Sci., 2014)

Classifying Nucleotide Sequences and their Positions of Influenza A Viruses through Several Kernels. - Issei Hamada; Takaharu Shimada; Daiki Nakata; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM (1), 2015)

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 (ICPRAM (1), 2015)

Alignment of Cyclically Ordered Trees. - Takuya Yoshino; Kouichi Hirata (ICPRAM (1), 2015)

Extracting Propagation Patterns from Bacterial Culture Data in Medical Facility. - Kazuki Nagayama; Kouichi Hirata; Shigeki Yokoyama; Kimiko Matsuoka (JSAI-isAI Workshops, 2015)

Fast Hilbert Sort Algorithm Without Using Hilbert Indices. - Yasunobu Imamura; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (SISAP, 2016)

Extracting Mutually Dependent Multisets. - Natsuki Kiyota; Sho Shimamura; Kouichi Hirata (DS, 2017)

Anchored Alignment Distance between Rooted Labeled Unordered Trees. - Kouichi Hirata; Takuya Yoshino; Yuma Ishizaka (FedCSIS, 2017)

Iterative Feature Selection Based on Binary Consistency. - Sho Shimamura; Kouichi Hirata (IIAI-AAI, 2017)

Pivot Selection for Dimension Reduction using Annealing by Increasing Resampling. - Yasunobu Imamura; Naoya Higuchi; Tetsuji Kuboyama; Kouichi Hirata; Takeshi Shinohara (LWDA, 2017)

Tai Mapping Hierarchy for Rooted Labeled Trees Through Common Subforest. - Takuya Yoshino; Kouichi Hirata (Theory Comput. Syst., 2017)

Path Histogram Distance for Rooted Labeled Caterpillars. - Taiga Kawaguchi; Takuya Yoshino; Kouichi Hirata (ACIIDS (1), 2018)

Computing Edit Distance between Rooted Labeled Caterpillars. - Kohei Muraka; Takuya Yoshino; Kouichi Hirata (FedCSIS, 2018)

LCA Histogram Distance for Rooted Labeled Caterpillars. - Takuya Yoshino; Kohei Muraka; Kouichi Hirata (KDIR, 2018)

Nearest Neighbor Search using Sketches as Quantized Images of Dimension Reduction. - Naoya Higuchi; Yasunobu Imamura; Tetsuji Kuboyama; Kouichi Hirata; Takeshi Shinohara (ICPRAM, 2018)

Earth Mover's Distances for Rooted Labaled Unordered Trees based on Tai Mapping Hierarchy. - Taiga Kawaguchi; Kouichi Hirata (ICPRAM, 2018)

Earth Mover's Distance Between Rooted Labeled Unordered Trees Formulated from Complete Subtrees. - Taiga Kawaguchi; Takuya Yoshino; Kouichi Hirata (ICPRAM (Revised Selected Papers), 2018)

Fast Filtering for Nearest Neighbor Search by Sketch Enumeration Without Using Matching. - Naoya Higuchi; Yasunobu Imamura; Tetsuji Kuboyama; Kouichi Hirata; Takeshi Shinohara (Australasian Conference on Artificial Intelligence, 2019)

Alignment for Rooted Labeled Caterpillars. - Yoshiyuki Ukita; Takuya Yoshino; Kouichi Hirata (FedCSIS (Position Papers), 2019)

Fast Nearest Neighbor Search with Narrow 16-bit Sketch. - Naoya Higuchi; Yasunobu Imamura; Tetsuji Kuboyama; Kouichi Hirata; Takeshi Shinohara (ICPRAM, 2019)

Annealing by Increasing Resampling. - Naoya Higuchi; Yasunobu Imamura; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM (Revised Selected Papers), 2019)

Annealing by Increasing Resampling in the Unified View of Simulated Annealing. - Yasunobu Imamura; Naoya Higuchi; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM, 2019)

Bipartite Edge Correlation Clustering: Finding an Edge Biclique Partition from a Bipartite Graph with Minimum Disagreement. - Mikio Mizukami; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM, 2019)

Vertical and Horizontal Distances to Approximate Edit Distance for Rooted Labeled Caterpillars. - Kohei Muraka; Takuya Yoshino; Kouichi Hirata (ICPRAM, 2019)

Introducing Fluctuation into Increasing Order of Symmetric Uncertainty for Consistency-Based Feature Selection. - Sho Shimamura; Kouichi Hirata (TAMC, 2019)

Heavy Caterpillar Distances for Rooted Labeled Unordered Trees. - Nozomi Abe; Takuya Yoshino; Kouichi Hirata (ICPRAM, 2020)

Detecting Geckler Classification from Gram Stained Smears Images for Sputum. - Kazuki Hashimoto; Ryosuke Iida; Kouichi Hirata; Kimiko Matsuoka; Shigeki Yokoyama (ICPRAM, 2020)

Detection System of Gram Types for Bacteria from Gram Stained Smears Images. - Ryosuke Iida; Kazuki Hashimoto; Kouichi Hirata; Kimiko Matsuoka; Shigeki Yokoyama (ICPRAM, 2020)

Pivot Selection for Narrow Sketches by Optimization Algorithms. - Naoya Higuchi; Yasunobu Imamura; Vladimir Mic; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (SISAP, 2020)

Path histogram distance and complete subtree histogram distance for rooted labelled caterpillars. - Taiga Kawaguchi; Takuya Yoshino; Kouichi Hirata (J. Inf. Telecommun., 2020)

Subcaterpillar Isomorphism: Subtree Isomorphism Restricted Pattern Trees To Caterpillars. - Tomoya Miyazaki; Kouichi Hirata (FedCSIS, 2022)

Computing the Variations of Edit Distance for Rooted Labaled Caterpillars. - Manami Hagihara; Takuya Yoshino; Kouichi Hirata (ICPRAM, 2022)

Nearest-neighbor Search from Large Datasets using Narrow Sketches. - Naoya Higuchi; Yasunobu Imamura; Vladimir Mic; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM, 2022)

Caterpillar Inclusion: Inclusion Problem for Rooted Labeled Caterpillars. - Tomoya Miyazaki; Manami Hagihara; Kouichi Hirata (ICPRAM, 2022)

Object Detection as Campylobacter Bacteria and Phagocytotic Activity of Leukocytes in Gram Stained Smears Images. - Kyohei Yoshihara; Kouichi Hirata (ICPRAM, 2022)

Segmental Distance between Rooted Labeled Caterpillars. - Manami Hagihara; Tomoya Miyazaki; Kouichi Hirata (IIAI-AAI, 2022)

Classifying Gram Positive Cocci and Gram Negative Bacilli in Gram Stained Smear Images. - Ibuki Kawano; Eri Kurumida; Syoma Terada; Kouichi Hirata (IIAI-AAI, 2022)

Object Detection as Gram Positive Cocci in Gram Stained Smear Images. - Hitoshi Sugimoto; Kouichi Hirata (IIAI-AAI, 2022)

Finding Correlated Mutations of Positions among Structural Proteins in SARS-CoV-2 Amino Acid Sequences. - Kan Yonashiro; Yuichi Shimaya; Kouichi Hirata (IIAI-AAI, 2022)

Subcaterpillar Isomorphism: Subtree Isomorphism for Rooted Labeled Caterpillars. - Tomoya Miyazaki; Kouichi Hirata (WCO, 2022)

Subcaterpillar Isomorphism Between Caterpillars: Subtree Isomorphism Restricted Text and Pattern Trees to Caterpillars. - Tomoya Miyazaki; Kouichi Hirata (ICPRAM, 2023)

Correlated Mutations of Positions Among Structural Proteins in Delta and Omicron Variants for SARS-CoV-2 Amino Acid Sequences. - Yuichi Shimaya; Kouichi Hirata (ICPRAM, 2023)

Sufficient Algorithm for Inclusion of Pattern Caterpillar in Text Tree. - Daisuke Abe; Tomoya Miyazaki; Kouichi Hirata (IIAI-AAI, 2023)

Detecting Infectious Disease-Causing Bacteria from Gram Stained Smears Images. - Ukyo Kashino; Syoma Terada; Kouichi Hirata (IIAI-AAI, 2023)

Distance-Based Analysis of Positions in Amino Acid Sequences for Structural Proteins of SARS-CoV-2 Delta and Omicron Variants. - Ryota Nagashima; Uran Yamamoto; Kouichi Hirata (IIAI-AAI, 2023)

Predicting Geckler Classification from Gram Stained Smears Images for Sputum: Image Classification versus Object Detection. - Hitoshi Sugimoto; Ryotaro Funatsu; Kouichi Hirata (IIAI-AAI, 2023)

Detecting Bacteria from Gram Stained Smears Images by the Family of YOLOs. - Ukyo Kashino; Kyosuke Taira; Kouichi Hirata (DMIP, 2024)

Detecting Phagocytotic Activity of Leukocytes in Gram Stained Smears Images. - Ryunosuke Nakajo; Kouichi Hirata (DMIP, 2024)

Predicting Yeast-Like Fungi from Gram Stained Smears Images. - Tsubasa Tanaka; Kouya Kagemoto; Kouichi Hirata (DMIP, 2024)

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 (ICPRAM, 2024)

Fast Filtering by Conjunctive Enumeration of Sketches for Nearest Neighbor Search. - Naoya Higuchi; Yasunobu Imamura; Vladimir Mic; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (ICPRAM, 2024)

Ancestral-Path Descendant-Labels Histogram Distance for Rooted Labeled Trees. - Daisuke Abe; Kouichi Hirata (IIAI-AAI, 2024)

Activation Functions for Detection of Bacteria from Gram Stained Smears Images by YOLOv8. - Kouya Kagemoto; Kouichi Hirata (IIAI-AAI, 2024)

Annotation Along Arranged Bacteria to Detect Gram Positive Cocci from Gram Stained Smears Images. - Ukyo Kashino; Mayu Yoshida; Kouichi Hirata (IIAI-AAI, 2024)

Data Augmentation for Detection of Bacteria from Gram Stained Smears Images by YOLOv8. - Ryunosuke Nakajo; Minori Tsutsui; Kouichi Hirata (IIAI-AAI, 2024)

Comparison with Detection of Bacteria from Gram Stained Smears Images by Various Object Detectors. - Tsubasa Tanaka; Kouichi Hirata (IIAI-AAI, 2024)

Double Filtering Using Short and Long Quantized Projections. - Naoya Higuchi; Yasunobu Imamura; Takeshi Shinohara; Kouichi Hirata; Tetsuji Kuboyama (SISAP, 2025)

Hilbert Forest in the SISAP 2025 Indexing Challenge. - Yasunobu Imamura; Takeshi Shinohara; Naoya Higuchi; Kouichi Hirata; Tetsuji Kuboyama (CoRR, 2025)