Assistant Professor (April 2023 – present),
Faculty of Materials for Energy,
Assistant Professor (April 2021 – March 2023),
Department of Electronics and Computer Science,
Graduate School of Engineering,
Research Fellow, advisor: Prof. Vincent Y. F. Tan (January 2019 – March 2021),
Department of Electrical and Computer Engineering (ECE),
National University of Singapore
Email-1: yuta [dot] sakai [at] mat [dot] shimane-u [dot] ac [dot] jp
Email-2: yuta [dot] sakai [at] ieee [dot] org
Email-3: yuta [dot] sakai [at] m [dot] ieice [dot] org
Link: ORCiD, ReseachGate, Google Scholar, dblp, Publons
D.E. in the Advanced Interdisciplinary Science and Technology at the University of Fukui, advisor: Prof. Ken-ichi Iwata (April 2016 – December 2018)
B.E. and M.E. in the Department of Information Science at the University of Fukui, advisor: Prof. Ken-ichi Iwata (April 2012 – March 2016)
Information Theory, Shannon Theory, Information Measures, Inequalities, Polarization Theory in Polar Coding, Second-Order Asymptotics, Error Exponents
(journal papers)
Yuta Sakai and Vincent Y. F. Tan, “On Smooth Rényi Entropies: A Novel Information Measure, One-Shot Coding Theorems, and Asymptotic Expansions,” IEEE Transactions on Information Theory, vol. 68, no. 3, pp. 1496–1531, March 2022. [arXiv] [slide]
Yuta Sakai, Recep Can Yavas, and Vincent Y. F. Tan, “Third-Order Asymptotics of Variable-Length Compression Allowing Errors,” IEEE Transactions on Information Theory, vol.67, no. 12, pp. 7708–7722, December 2021. [arXiv]
Yuta Sakai and Vincent Y. F. Tan, “Variable-Length Source Dispersions Differ under Maximum and Average Error Criteria,” IEEE Transactions on Information Theory, vol. 66, no. 12, pp. 7565–7587, December 2020. [arXiv] [slide]
Yuta Sakai, Vincent Y. F. Tan, and Mladen Kovačević, “Second- and Third-Order Asymptotics of the Continuous-Time Poisson Channel,” IEEE Transactions on Information Theory, vol. 66, no. 8, pp. 4742–4760, August 2020. [arXiv] [slide1] [slide2]
Yuta Sakai, Ken-ichi Iwata, and Hiroshi Fujisaki, “Modular Arithmetic Erasure Channels and Their Multilevel Channel Polarization,” IEEE Transactions on Information Theory, vol. 66, no. 7, pp. 3976–4006, July 2020. [arXiv] [slide]
Yuta Sakai, “Generalizations of Fano's Inequality for Conditional Information Measures via Majorization Theory,” Entropy (invited to the special issue: Information Measures with Applications), vol. 22, no. 3, 59 pages, March 2020. [arXiv]
Yuta Sakai and Ken-ichi Iwata, “Extremality Between Symmetric Capacity and Gallager’s Reliability Function E0 for Ternary-Input Discrete Memoryless Channels,” IEEE Transactions on Information Theory, vol. 64, no. 1, pp. 163–191, January 2018.
(conference papers)
Yuta Sakai and Vincent Y. F. Tan, "Third-Order Asymptotics of Variable-Length Compression Allowing Errors," in Proceedings of the 2020 International Symposium on Information Theory and Its Applications (ISITA'20), Kapolei, HI, USA, October 2020, pp. 76–80. [arXiv]
Yuta Sakai and Vincent Y. F. Tan, "On the Second- and Third-Order Asymptotics of Smooth Rényi Entropy and Their Applications," in Proceedings of the 2020 IEEE International Symposium on Information Theory (ISIT'20), Los Angeles, CA, USA, June 2020, pp. 2298–2303. [slide]
Yuta Sakai and Vincent Y. F. Tan, "Variable-Length Source Dispersions Differ under Maximum and Average Error Criteria," in Proceedings of the 2020 IEEE International Symposium on Information Theory (ISIT'20), Los Angeles, CA, USA, June 2020, pp. 2173–2178. [slide]
Yuta Sakai, Mladen Kovačević, and Vincent Y. F. Tan, “Second-Order Asymptotics for the Continuous-Time Poisson Channel,” in Proceedings of the 2019 IEEE Information Theory Workshop (ITW'19), Visby, Gotland, Sweden, August 2019. [arXiv] [poster]
Yuta Sakai, Ken-ichi Iwata, and Hiroshi Fujisaki, “Countably Infinite Multilevel Source Polarization for Non-Stationary Erasure Distributions,” in Proceedings of the 2019 IEEE International Symposium on Information Theory (ISIT'19), Paris, France, July 2019, pp. 2109–2113. [arXiv] [slide]
Yuta Sakai, “Generalized Fano-Type Inequality for Countably Infinite Systems with List-Decoding,” in Proceedings of the 2018 International Symposium on Information Theory and its Applications (ISITA'18), Singapore, October 2018, pp. 727–731. [slide]
Yuta Sakai, Ken-ichi Iwata, and Hiroshi Fujisaki, “Asymptotic Distribution of Multilevel Channel Polarization for A Certain Class of Erasure Channels,” in Proceedings of the 2018 IEEE International Symposium on Information Theory (ISIT'18), Vail, CO, USA, June 2018, pp. 856–860. [arXiv] [slide]
Yuta Sakai and Ken-ichi Iwata, “Dynamic Programming Approach of Optimal Upgradation Algorithm for An Auxiliary Random Variable of A Bernoulli Random Variable,” in Proceedings of the 2018 IEEE International Symposium on Information Theory (ISIT'18), Vail, CO, USA, June 2018, pp. 146–150. [slide]
Yuta Sakai and Ken-ichi Iwata, “Sharp Bounds on Arimoto’s Conditional Rényi Entropies Between Two Distinct Orders,” in Proceedings of the 2017 IEEE International Symposium on Information Theory (ISIT'17), Aachen, Germany, June 2017, pp. 2985–2989. [arXiv] [slide]
Yuta Sakai and K. Iwata, “Optimal Quantization of B-DMCs Maximizing α-Mutual Information with Monge Property,” in Proceedings of the 2017 IEEE International Symposium on Information Theory (ISIT'17), Aachen, Germany, June 2017, pp. 2673–2677. [slide]
Yuta Sakai and Ken-ichi Iwata, “Extremality for Error Exponents of q-Ary Input Discrete Memoryless Channels,” in Proceedings of the 10th Asia-Europe Workshop on Concepts in Information theory (AEW10), Boppard, Germany, June 2017, page 7. [arXiv] [slide]
Yuta Sakai and Ken-ichi Iwata, “A Generalized Erasure Channel in the Sense of Polarization for Binary Erasure Channels,” in Proceedings of the 2016 IEEE Information Theory Workshop (ITW'16), Cambridge, UK, September 2016. [arXiv] [slide]
Yuta Sakai and Ken-ichi Iwata, “Extremal Relations Between Shannon Entropy and ℓα-Norm,” in Proceedings of the 2016 International Symposium on Information Theory and its Applications (ISITA'16), Monterey, CA, USA, November 2016, pp. 433–437. [arXiv] [slide]
Yuta Sakai and Ken-ichi Iwata, “Relations Between Conditional Shannon Entropy and Expectation of ℓα-Norm,” in Proceedings of the 2016 IEEE International Symposium on Information Theory (ISIT'16), Barcelona, Spain, July 2016, pp. 1641–1645. [arXiv] [slide]
Yuta Sakai and Ken-ichi Iwata, “Feasible Regions of Symmetric Capacity and Gallager’s E0 Function for Ternary-Input Discrete Memoryless Channels,” in Proceedings of the 2015 IEEE International Symposium on Information Theory (ISIT'15), Hong Kong, June 2015, pp. 81–85. [slide]
Yuta Sakai and Ken-ichi Iwata, “Suboptimal Quantizer Design for Output of Discrete Memoryless Channels with a Finite-Input Alphabet,” in Proceedings of the 2014 International Symposium on Information Theory and its Applications (ISITA'14), Melbourne, Australia, October 2014, pp. 120–124. [slide]
(non-international, Japanese, conference papers)
Yuta Sakai, Ken-ichi Iwata, and Hiroshi Fujisaki, “Concrete Examples of Countably Infinite Multilevel Source Polarization with A Certain Infinite Group,” in Proceedings of the 41st Symposium on Information Theory and its Applications (SITA'18), Fukushima, Japan, December 2018, pp. 206–211.
Yuta Sakai, Ken-ichi Iwata, and Hiroshi Fujisaki, “Asymptotic Distribution of Multilevel Channel Polarization for A Certain Class of Erasure Channels,” in Proceedings of the 40th Symposium on Information Theory and its Applications (SITA'17), Niigata, Japan, December 2017, pp. 452–457.
Yuta Sakai and Ken-ichi Iwata, “Dynamic Programming Approach of Optimal Upgradation Algorithm for An Auxiliary Random Variable of A Bernoulli Random Variable,” in Proceedings of the 40th Symposium on Information Theory and its Applications (SITA'17), Niigata, Japan, December 2017, pp. 446–451.
Yuta Sakai and Ken-ichi Iwata, “Extremality for Arimoto’s Conditional Rényi Entropy and Error Exponents of Gallager’s Form,” in Proceedings of the 10th Shannon Theory Workshop (STW'17), Hyogo, Japan, October 2017, pp. 46–53. [slide]
Yuta Sakai and Ken-ichi Iwata, “A Study on Sharma–Mittal Entropy in Terms of Pseudo-Additivity and Aczél–Daróczy Uniqueness Theorem of Rényi Entropy,” in Proceedings of the 39th Symposium on Information Theory and its Applications (SITA'16), Gifu, Japan, December 2016, pp. 585–590. [slide]
Yuta Sakai and Ken-ichi Iwata, “Easily Analyzable q-Ary Input Discrete Memoryless Channels for Polar Transforms with Modulo-q Operations,” in Proceedings of the 38th Symposium on Information Theory and its Applications (SITA'15), in Japanese, Okayama, Japan, November 2015, pp. 589–594.
Yuta Sakai and Ken-ichi Iwata, “Range of Reliability Functions Among Ternary-Input Memoryless and Symmetric Channels with Same Capacity,” in Proceedings of the 37th Symposium on Information Theory and its Applications (SITA'14), in Japanese, Toyama, Japan, December 2014, pp. 656–661.
(Japanese technical reports)
Yuta Sakai, “On the Generalization of Fano’s Inequality for Countably Infinite Alphabets, List-Decoding, and General Conditional Information Measures,” IEICE Technical Reports, vol. 117, no. 478, March 2018, pp. 179–184.
Yuta Sakai and Ken-ichi Iwata, “Speed-Up Method for Optimal Quantizations of Binary-Input Discrete Memoryless Channels with Monge Property,” IEICE Technical Reports, vol. 116, no. 206, September 2016, pp. 35–40.
Tomoyuki Kiuchi, Yuta Sakai, and Ken-ichi Iwata, “Construction, Encoding, and Decoding of Polar Codes with Multilevel Polarization for q-Ary Input Generalized Erasure Channels,” IEICE Technical Reports (in Japanese), vol. 116, no. 206, September 2016, pp. 13–18.
Yuta Sakai and Ken-ichi Iwata, “A Sharp Bound Between Two Arimoto’s Conditional Rényi Entropies with Distinct Positive Orders,” IEICE Technical Reports (in Japanese), vol. 116, no. 33, May 2016, pp. 63–68.
Yuta Sakai and Ken-ichi Iwata, “Relations Between Conditional Shannon Entropy and Expectation of Norm and Their Applications,” IEICE Technical Reports (in Japanese), vol. 115, no. 500, March 2016, pp. 49–54.
Yuta Sakai and Ken-ichi Iwata, “Feasible Regions of Symmetric Capacity and Gallager’s E0 Functions for Discrete Memoryless Channels Under A Uniform Input Distribution,” IEICE Technical Reports (in Japanese), vol. 115, no. 37, May 2015, pp. 7–12.
Takumi Nagahara, Yuta Sakai, and Ken-ichi Iwata, “Algorithms to Reduce The Number of Output Symbols on Condition That Discrete Memoryless Channel Satisfies Admissible Mutual Information,” IEICE Technical Reports (in Japanese), vol. 114, no. 470, March 2015, pp. 153–158.
Yuta Sakai and Ken-ichi Iwata, “Range of Symmetric Capacity and Reliability Functions for Ternary-Input Discrete Memoryless Channels with Uniform Input Distribution,” IEICE Technical Reports (in Japanese), vol. 114, no. 438, January 2015, pp. 7–12.
Yuta Sakai and Ken-ichi Iwata, “On Quantization by Greedy Combining for Outputs of Discrete Memoryless Channels,” IEICE Technical Reports (in Japanese), vol. 114, no. 138, July 2014, pp. 127–132.
(invited talks)
Yuta Sakai, "Possible Generalizations of Fano's Inequality on Countably Infinite Alphabets with List Decoding," at the Saturday Seminar in UEC, Chofu, Tokyo, Japan, December 2018. [slide]
Yuta Sakai, “An Introduction to Polar Codes,” at the 5th Error Correcting Codes Workshop (ECCW'16), Saga, Japan, September 2016 (in Japanese).
Exemplary Reviewer of IEEE Transactions on Communications, 2018. [pdf]
IEEE Nagoya Section Conference Presentation Award, 2017, presented at the 2016 IEEE International Symposium on Information Theory. [pdf]
Symposium on Information Theory and its Applications Young Researcher Paper Award (情報理論とその応用シンポジウム奨励賞, SITA奨励賞), 2016, presented at the 38th Symposium on Information Theory and its Applications (in Japanese). [pdf]
IEEE Information Theory Society Japan Chapter Young Researcher Best Paper Award, 2016, presented at the 2016 International Symposium on Information Theory and its Applications. [pdf]
International Symposium on Information Theory and its Applications Student Paper Award, 2016, presented at the 2016 International Symposium on Information Theory and its Applications. [pdf]
Research Society of Information Theory and its Applications --- Student Presentation Award (情報理論とその応用サブソサイエティ学生優秀発表), 2016, presented at the Technical Committee on Information Theory (in Japanese). [pdf]
Japan Society for the Promotion of Science (JSPS) KAKENHI Grant-in-Aid for Early-Career Scientists (日本学術振興会 科学研究費助成事業 若手研究), grant number: 23K16839, April 2023 – March 2028. (budget amount: 4,810,000 JPY)
Japan Society for the Promotion of Science (JSPS) KAKENHI Grant-in-Aid for Research Activity Start-up (日本学術振興会 科学研究費助成事業 研究活動スタート支援), grant number: 21K21291, August 2021 – March 2023. (budget amount: 3,120,000 JPY)
Japan Society for the Promotion of Science (JSPS) KAKENHI Research Fellowship for Young Scientists (日本学術振興会 特別研究員 DC2), grant number: 17J11247, April 2017 – December 2018 (a monthly stipend of 200,000 JPY and a research grant of 1,700,000 JPY)
IEEE International Symposium on Information Theory Student Travel Support, 2017 (a travel grant of 500 USD, presented at the 2017 IEEE International Symposium on Information Theory)
Grant for Researchers Attending International Conferences by NEC C&C Foundation (公益財団法人 NEC C&C財団 国際会議論文発表者助成), 2017 (a travel grant of 250,000 JPY, presented at the 2017 IEEE International Symposium on Information Theory)
Travel Grant by Research Foundation for the Electrotechnology of Chubu (公益財団法人 中部電気利用基礎研究振興財団 海外渡航費援助), 2016 (a travel grant of 150,000 JPY, presented at the 2016 IEEE Information Theory Workshop)
Travel Grant by the Telecommunications Advancement Foundation (公益財団法人 電気通信普及財団 海外渡航旅費援助), 2016 (a travel grant of 290,000 JPY, presented at the 2016 IEEE International Symposium on Information Theory)
Travel Grant by the Murata Science Foundation (公益財団法人 村田学術振興会 研究者海外派遣援助), 2015 (a travel grant of 200,000 JPY, presented at the 2015 IEEE International Symposium on Information Theory)
International Symposium on Information Theory and its Applications Young Researcher Travel Grant, 2014 (a travel grant of 400 AUD, presented at the 2014 International Symposium on Information Theory and its Applications)