Proposal of the-law-of-inertia (friction/gravity-free) robots. - Suguru Arimoto; Hiroki Koga; Tomohide Naniwa (ICRA, 1997)

A General Formula of the (t, n)-Threshold Visual Secret Sharing Scheme. - Hiroki Koga (ASIACRYPT, 2002)

New Constructions of the Lattice-Based Visual Secret Sharing Scheme Using Mixture of Colors. - Takeru Ishihara; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2002)

A Constraint-based Grammar of Case : To Correctly Predict Case Phrases Occurring without Their Head Verb. - Hiroki Koga (PACLIC, 2003)

A Visual Secret Sharing Scheme for Color Images Based on Meanvalue-Color Mixing. - Takeru Ishihara; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2003)

On the Problem of Generating Mutually Independent Random Sequences. - Jun Muramatsu; Hiroki Koga; Takafumi Mukouchi (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2003)

Source coding using a class of universal hash functions. - Hiroki Koga (ISIT, 2004)

On an upper bound of the secrecy capacity for a general wiretap channel. - Hiroki Koga; Naoki Sato (ISIT, 2005)

Asymptotic properties on codeword lengths of an optimal FV code for general sources. - Hiroki Koga; Hirosuke Yamamoto (IEEE Trans. Inf. Theory, 2005)

Proposal of an Asymptotically Contrast-Ideal (t, n)- Threshold Visual Secret Sharing Scheme. - Hiroki Koga; Etsuyo Ueda (ISIT, 2006)

Basic Properties of the (t, n)-Threshold Visual Secret Sharing Scheme with Perfect Reconstruction of Black Pixels. - Hiroki Koga; Etsuyo Ueda (Des. Codes Cryptogr., 2006)

Coding Theorems for General Stegosystems. - Hiroki Koga; Isao Nakano (ISIT, 2007)

Source Coding Using Families of Universal Hash Functions. - Hiroki Koga (IEEE Trans. Inf. Theory, 2007)

Coding Theorems on the Threshold Scheme for a General Source. - Hiroki Koga (IEEE Trans. Inf. Theory, 2008)

A coding theorem for cheating-detectable (2, 2)-threshold blockwise secret sharing schemes. - Mitsugu Iwamoto; Hirosuke Yamamoto; Hiroki Koga (ISIT, 2009)

Development and Experimental Evaluation of Oral Rehabilitation Robot that Provides Maxillofacial Massage to Patients with Oral Disorders. - Hiroyuki Ishii; Hiroki Koga; Yuichi Obokawa; Jorge Solis 001; Atsuo Takanishi; Akitoshi Katsumata (Int. J. Robotics Res., 2009)

A simple secret sharing scheme using a key and its security against substitution of shares. - Hiroki Koga (ISIT, 2010)

Two generalizations of a coding theorem for a (2, 2)-threshold scheme with a cheater. - Hiroki Koga (ISITA, 2010)

Path generator control system and virtual compliance calculator for maxillofacial massage robots. - Hiroyuki Ishii; Hiroki Koga; Yuichi Obokawa; Jorge Solis 001; Atsuo Takanishi; Akitoshi Katsumata (Int. J. Comput. Assist. Radiol. Surg., 2010)

Coding Theorems for Cheating-Detectable Secret Sharing Schemes with Two Shares - Mitsugu Iwamoto; Hiroki Koga; Hirosuke Yamamoto (CoRR, 2010)

Coding theorems on the worst-case redundancy of fixed-length coding for a general source. - Hiroki Koga; Mitsuharu Arimura; Ken-ichi Iwata (ISIT, 2011)

A general method for construction of (t, n)-threshold visual secret sharing schemes for color images. - Hiroki Koga; Takeru Ishihara (Des. Codes Cryptogr., 2011)

Four Limits in Probability and Their Roles in Source Coding. - Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2011)

A Digital Fingerprinting Code Based on a Projective Plane and Its Identifiability of All Malicious Users. - Hiroki Koga; Yusuke Minami (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2011)

On the role of mutual infomation between the shares in a robust (k, n)-threshold scheme. - Hiroki Koga; Kazuya Koyano (ISITA, 2012)

On the Achievable Rate Region in the Optimistic Sense for Separate Coding of Two Correlated General Sources. - Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2012)

Coding Theorems for a (2, 2)-Threshold Scheme With Detectability of Impersonation Attacks. - Mitsugu Iwamoto; Hiroki Koga; Hirosuke Yamamoto (IEEE Trans. Inf. Theory, 2012)

Characterization of the smooth Rényi Entropy Using Majorization. - Hiroki Koga (ITW, 2013)

Redundancy-Optimal FF Codes for a General Source and Its Relationships to the Rate-Optimal FF Codes. - Mitsuharu Arimura; Hiroki Koga; Ken-ichi Iwata (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2013)

A Characterization of Optimal FF Coding Rate Using a New Optimistically Optimal Code. - Mitsuharu Arimura; Hiroki Koga; Ken-ichi Iwata (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2013)

Resolution of resource conflicts in the CCPM framework using a local search method. - Hiroki Koga; Hiroyuki Goto; Eishi Chiba (IEEM, 2014)

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 (ISIT, 2014)

On the capacity and the zero-error capacity of k-resilient AND anti-collusion codes. - Hiroki Koga (ITW, 2014)

Multiple neural mechanisms for coloring words in synesthesia. - Takemasa Yokoyama; Yasuki Noguchi; Hiroki Koga; Ryosuke Tachibana; Jun Saiki; Ryusuke Kakigi; Shinichi Kita (NeuroImage, 2014)

On a partition of a finite set and its relationships to encoding tasks and the Rényi entropy. - Hiroki Koga (ISIT, 2015)

A Higher Order Analysis of the Joint Capacity of Digital Fingerprinting Codes against the Interleaving Attack. - Hiroki Koga; Kaoru Itabashi (IH&MMSec, 2016)

New fundamental properties on a secret-key cryptosystem under guessing secrecy criteria. - Shota Kamiya; Hiroki Koga (ISITA, 2016)

4.6 A 1/2.3inch 20Mpixel 3-layer stacked CMOS Image Sensor with DRAM. - Tsutomu Haruta; Tsutomu Nakajima; Jun Hashizume; Taku Umebayashi; Hiroshi Takahashi; Kazuo Taniguchi; Masami Kuroda; Hiroshi Sumihiro; Koji Enoki; Takatsugu Yamasaki; Katsuya Ikezawa; Atsushi Kitahara; et al. (ISSCC, 2017)

A construction of the progressive (3, n)-threshold visual cryptography using a BIBD and analysis of its optimality. - Koutaro Okada; Hiroki Koga (ITW, 2017)

Foreword. - Jun Muramatsu; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2017)

A Lower Bound on the Joint Capacity of Digital Fingerprinting Codes Using Score Functions Based on Log-Likelihood Ratio. - Hiroki Koga (ISIT, 2018)

A Construction of the (4, n)-Threshold Visual Cryptography Scheme Using a 3-Design. - Koutaro Okada; Hiroki Koga (ISITA, 2018)

Novel Proximity Sensor for Realizing Tactile Sense in Suction Cups. - Sayaka Doi; Hiroki Koga; Tomonori Seki; Yutaro Okuno (ICRA, 2020)

An Ideal Secret Sharing Scheme Realizing an Access Structure Based on a Finite Projective Plane of Order 3. - Yohei Okawa; Hiroki Koga (ISIT, 2020)

Coding Theorems on the Simple Capacity for Digital Fingerprinting Codes. - Hiroki Koga (ISITA, 2020)

New Constructions of an Evolving 2-Threshold Scheme Based on Binary or D-ary Prefix Codes. - Ryo Okamura; Hiroki Koga (ISITA, 2020)

Coding Theorems on Digital Fingerprinting Coding under Informed and Uninformed Setups. - Hiroki Koga (ITW, 2021)

Analog In-memory Computing in FeFET-based 1T1R Array for Edge AI Applications. - Daisuke Saito; Toshiyuki Kobayashi; Hiroki Koga; Nicolo Ronchi; Kaustuv Banerjee; Yusuke Shuto; Jun Okuno; Kenta Konishi; Luca Di Piazza; Arindam Mallik; Jan Van Houdt; Masanori Tsukamoto; et al. (VLSI Circuits, 2021)

Optimal Basis Matrices of a Visual Cryptography Scheme with Meaningful Shares and Analysis of Its Security. - Kyohei Sekine; Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2021)

Construction of the Visual Cryptography Scheme with the Maximum Relative Difference under a Strong General Access Structure. - Hiroki Koga (ISIT, 2022)

On the Optimal Construction of a Visual Cryptography Scheme for Multiple Secret Images. - Raiki Ioki; Hiroki Koga (ISITA, 2022)

On the Optimum Achievable Rates of a Coded Caching Scheme with Small Cache Memory. - Akihito Nagaya; Hiroki Koga (ISITA, 2022)

Foreword. - Hiroki Koga (IEICE Trans. Fundam. Electron. Commun. Comput. Sci., 2023)

Constructions of a Visual Cryptography Scheme Using an Affine Resolvable BIBD. - Naoki Mitarai; Hiroki Koga (ISITA, 2024)

An Explicit Construction of a Coded Caching Scheme with Heterogeneous Cache Sizes. - Akihito Nagaya; Hiroki Koga (ISITA, 2024)