| 2025 | ASIACRYPT | New Tight Bounds on the Local Leakage Resilience of the Additive (n, n)-Threshold Scheme Determined by the Eigenvalues of Circulant Matrices. | Hiroki Koga, Hiroto Abe |
| 2024 | ISITA | Constructions of a Visual Cryptography Scheme Using an Affine Resolvable BIBD. | Naoki Mitarai, Hiroki Koga |
| 2024 | ISITA | An Explicit Construction of a Coded Caching Scheme with Heterogeneous Cache Sizes. | Akihito Nagaya, Hiroki Koga |
| 2022 | ISIT | Construction of the Visual Cryptography Scheme with the Maximum Relative Difference under a Strong General Access Structure. | Hiroki Koga |
| 2022 | ISITA | On the Optimal Construction of a Visual Cryptography Scheme for Multiple Secret Images. | Raiki Ioki, Hiroki Koga |
| 2022 | ISITA | On the Optimum Achievable Rates of a Coded Caching Scheme with Small Cache Memory. | Akihito Nagaya, Hiroki Koga |
| 2021 | ITW | Coding Theorems on Digital Fingerprinting Coding under Informed and Uninformed Setups. | Hiroki Koga |
| 2020 | ICRA | Novel Proximity Sensor for Realizing Tactile Sense in Suction Cups. | Sayaka Doi, Hiroki Koga, Tomonori Seki, Yutaro Okuno |
| 2020 | ISIT | An Ideal Secret Sharing Scheme Realizing an Access Structure Based on a Finite Projective Plane of Order 3. | Yohei Okawa, Hiroki Koga |
| 2020 | ISITA | Coding Theorems on the Simple Capacity for Digital Fingerprinting Codes. | Hiroki Koga |
| 2020 | ISITA | New Constructions of an Evolving 2-Threshold Scheme Based on Binary or D-ary Prefix Codes. | Ryo Okamura, Hiroki Koga |
| 2020 | ISITA | Optimal Basis Matrices of a Visual Cryptography Scheme with Meaningful Shares and Analysis of Its Security. | Kyohei Sekine, Hiroki Koga |
| 2018 | ISIT | A Lower Bound on the Joint Capacity of Digital Fingerprinting Codes Using Score Functions Based on Log-Likelihood Ratio. | Hiroki Koga |
| 2018 | ISITA | A Construction of the (4, n)-Threshold Visual Cryptography Scheme Using a 3-Design. | Koutaro Okada, Hiroki Koga |
| 2017 | ITW | A construction of the progressive (3, n)-threshold visual cryptography using a BIBD and analysis of its optimality. | Koutaro Okada, Hiroki Koga |
| 2016 | ISITA | New fundamental properties on a secret-key cryptosystem under guessing secrecy criteria. | Shota Kamiya, Hiroki Koga |
| 2015 | ISIT | On a partition of a finite set and its relationships to encoding tasks and the Rnyi entropy. | Hiroki Koga |
| 2014 | ISIT | A secret sharing scheme based on a systematic Reed-Solomon code and analysis of its security for a general class of sources. | Hiroki Koga, Shuntaro Honjo |
| 2014 | ITW | On the capacity and the zero-error capacity of k-resilient AND anti-collusion codes. | Hiroki Koga |
| 2013 | ITW | Characterization of the smooth Rnyi Entropy Using Majorization. | Hiroki Koga |
| 2012 | ISITA | On the role of mutual infomation between the shares in a robust (k, n)-threshold scheme. | Hiroki Koga, Kazuya Koyano |
| 2011 | ISIT | Coding theorems on the worst-case redundancy of fixed-length coding for a general source. | Hiroki Koga, Mitsuharu Arimura, Ken-ichi Iwata |
| 2010 | ISIT | A simple secret sharing scheme using a key and its security against substitution of shares. | Hiroki Koga |
| 2010 | ISITA | Two generalizations of a coding theorem for a (2, 2)-threshold scheme with a cheater. | Hiroki Koga |
| 2009 | ISIT | A coding theorem for cheating-detectable (2, 2)-threshold blockwise secret sharing schemes. | Mitsugu Iwamoto, Hirosuke Yamamoto, Hiroki Koga |
| 2007 | ISIT | Coding Theorems for General Stegosystems. | Hiroki Koga, Isao Nakano |
| 2006 | ISIT | Proposal of an Asymptotically Contrast-Ideal (t, n)- Threshold Visual Secret Sharing Scheme. | Hiroki Koga, Etsuyo Ueda |
| 2005 | ISIT | On an upper bound of the secrecy capacity for a general wiretap channel. | Hiroki Koga, Naoki Sato |
| 2004 | ISIT | Source coding using a class of universal hash functions. | Hiroki Koga |
| 2003 | PACLIC | A Constraint-based Grammar of Case : To Correctly Predict Case Phrases Occurring without Their Head Verb. | Hiroki Koga |
| 2002 | ASIACRYPT | A General Formula of the (t, n)-Threshold Visual Secret Sharing Scheme. | Hiroki Koga |
| 1997 | ICRA | Proposal of the-law-of-inertia (friction/gravity-free) robots. | Suguru Arimoto, Hiroki Koga, Tomohide Naniwa |