■Faculty | Department of Informatics |

■Position | Lecturer |

■Degree | |

■Commentator Guide | https://www.kindai.ac.jp/meikan/476-moriya-sen.html |

■URL | |

Last Updated :2020/09/30

- - 2000 , Nara Institute of Science and Technology, Graduate School of Information Science
- - 1995 , Osaka University, School of Science

- Informatics, Information theory

- Coding Theory, fault tolerance, distributed system, algorithms

- Hybrid P2P Distributed Checkpointing and Rollback Algorithms for Distributed Applications and Their Evaluations, AZUMA Ryoto, MORIYA Sen, IEICE Transactions on Information and Systems (Japanese Edition), IEICE Transactions on Information and Systems (Japanese Edition), J103-D(1), 1 - 12, Jan. 2020 , Refereed
- A Study on Constructing High Rate Punctured Convolutional Codes by Using Dual Codes, Kana Kikuchi, Hiroshi Sasano, Sen Moriya, IEICE Transactions on Fundamentals (Japanese Edition), IEICE Transactions on Fundamentals (Japanese Edition), J96-A(10), 726 - 730, Oct. 2013 , Refereed
- A Construction of high rate convolutional codes, Hiroshi Sasano, Sen Moriya, IEICE Transactions on Fundamentals (Japanese Edition), IEICE Transactions on Fundamentals (Japanese Edition), J96-A(7), 502 - 505, Jul. 2013 , Refereed
- Dynamic Snapshot Algorithm and Partial Rollback Algorithm for Internet Agents, Sen Moriya, Tadashi Araragi, IEICE Transactions on Information and Systems (Japanese Edition), IEICE Transactions on Information and Systems (Japanese Edition), J86-D(5), 301 - 317, May 2003 , Refereed
- Dynamic Snapshot Algorithm and Partial Rollback Algorithm for Internet Agents, Sen Moriya, Tadashi Araragi, 15th International Symposium on Distributed Computing, 15th International Symposium on Distributed Computing, Oct. 2001 , Refereed
- Optimal Wait-free Clock Synchronization Protocol on a Shared-memory Multi-processor System, Sen Moriya, Michiko Inoue, Toshimitsu Masuzawa, Hideo Fujiwara, IEICE Transactions on Information and Systems (Japanese Edition), IEICE Transactions on Information and Systems (Japanese Edition), J83-D(1), 99 - 109, Jan. 2000 , Refereed
- Wait-Free Linearizable Distributed Shared Memory, S. Moriya, K. Suda, M. Inoue, T. Masuzawa, H. Fujiwara, Proc. of the 11th IASTED International Conference on Parallel and Distributed Computing and Systems, Proc. of the 11th IASTED International Conference on Parallel and Distributed Computing and Systems, 335 - 342, Nov. 1999 , Refereed
- Self-Stabilizing Wait-Free Clock Synchronization with Bounded Space, Sen Moriya, Michiko Inoue, Toshimitsu Masuzawa, Hideo Fujiwara, Proc. of the 2nd International Conference on Principles of Distributed Systems, Proc. of the 2nd International Conference on Principles of Distributed Systems, 129 - 143, Dec. 1998 , Refereed
- Search for high-rate punctured convolutional codes through transformed identical codes, Sen Moriya, Kana Kikuchi, Hiroshi Sasano, IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, IEICE Transactions on Fundamentals of Electronics, Communications and Computer Sciences, E100A(12), 2607 - 2614, Dec. 01 2017 , RefereedSummary:In this study, we consider techniques to search for highrate punctured convolutional code (PCC) encoders by rearranging row vectors of identical-encoder generator matrices. One well-known method to obtain a good PCC encoder is to perform an exhaustive search of all candidates. However, this approach is time-intensive. An exhaustive search with a rate RG = 1/2 original encoder requires a relatively short time, whereas that with an RG = 1/3 or lower original encoder takes significantly longer. The encoders with lower-rate original encoders are expected to create better PCC encoders. Thus, this paper proposes a method that uses exhaustive search results with rate RG = 1/2 original encoders, and rearranges row vectors of identical-encoder generator matrices to create PCCs with a lower rate original code. Further, we provide PCC encoders obtained by searches that utilize our method.
- Efficient Search for High-Rate Punctured Convolutional Codes Using Dual Codes, Sen Moriya, Kana Kikuchi, Hiroshi Sasano, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E99A(12), 2162 - 2169, Dec. 2016 , RefereedSummary:In this study, we consider techniques to search for highrate punctured convolutional code (PCC) encoders using dual code encoders. A low-rate R = 1/n convolutional code (CC) has a dual code that is identical to a PCC with rate R = (n - 1)/n. This implies that a rate R = 1/n convolutional code encoder can assist in searches for high-rate PCC encoders. On the other hand, we can derive a rate R = 1/n CC encoder from good PCC encoders with rate R = (n = 1)/n using dual code encoders. This paper proposes a method to obtain improved high-rate PCC encoders, using exhaustive search results of PCC encoders with rate R = 1/3 original encoders, and dual code encoders. We also show some PCC encoders obtained by searches that utilized our method.
- Construction of High Rate Punctured Convolutional Codes through Identical Codes, Hiroshi Sasano, Kana Kikuchi, Sen Moriya, PROCEEDINGS OF 2016 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA 2016), PROCEEDINGS OF 2016 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA 2016), 498 - 501, 2016 , RefereedSummary:There exists an identical high rate ordinary convolutional code with a punctured convolutional code. We show a method for obtaining good rate R = (n - 1) / n punctured convolutional codes through the identical codes with the best punctured convolutional codes of rate (n - 1) / n obtained by exhaustive searches for rate 1/2 original codes and puncturing matrices, and the method can find out punctured convolutional codes superior to the best code obtained by exhaustive searches for rate 1/3 original codes and puncturing matrices. For generating matrices of identical codes, we construct new identical codes with punctured convolutional codes by combining row vectors of each individual matrix. We present good punctured convolutional codes with rate R = (n - 1) / n,n = 6, ... , 13 by computer searches through those identical codes.
- Construction of High-Rate Punctured Convolutional Codes through Dual Codes, Sen Moriya, Kana Kikuchi, Hiroshi Sasano, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E98A(7), 1579 - 1583, Jul. 2015 , RefereedSummary:This paper considers a method for constructing good highrate punctured convolutional codes through dual codes. A low-rate R = 1/n convolutional code has a dual code identical to a punctured convolutional code with rate R = (n - 1)/n. This implies that a low-rate R = 1/n convolutional code encoder can help the search of punctured convolutional code encoders. This paper provides the procedures that obtain all the useful dual code encoders to a given CC with rate R = 1/n easily, and the best PCC encoder with rate R = (n - 1)/n among the encoders we derive from all the obtained dual code encoders. This paper also shows an example of the PCC the procedures obtain from some CC.
- Construction of High-rate Punctured Convolutional Codes through Dual Codes, Kana Kikuchi, Sen Moriya, Hiroshi Sasano, 2014 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA), 2014 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA), 100 - 104, 2014 , RefereedSummary:Punctured convolutional codes are error-correcting codes that can be used to achieve reliable data transfer in digital communication systems. This paper considers a method to search good high-rate punctured convolutional code encoders using dual codes, which are often utilized to evaluate block codes. A low-rate R = 1/n convolutional code has a dual code identical to a punctured convolutional code with rate R = (n - 1)/n. This implies that a low-rate R = 1/n convolutional code can help the search of punctured convolutional code encoders. In simple terms, this means that the strategy involves searching all of many candidate dual code encoders. This paper shows it is not difficult to list all the useful dual code encoders from a given convolutional code with rate R = 1/n, and we give some examples of the best punctured convolutional code encoder with rate R = (n 1)/n obtained through dual code.
- Construction of High Rate Punctured Convolutional Codes by Exhaustive Search and Partial Search, Sen Moriya, Hiroshi Sasano, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, IEICE TRANSACTIONS ON FUNDAMENTALS OF ELECTRONICS COMMUNICATIONS AND COMPUTER SCIENCES, E96A(12), 2374 - 2381, Dec. 2013 , RefereedSummary:We consider two methods for constructing high rate punctured convolutional codes. First, we present the best high rate R = (n-1)/n punctured convolutional codes, for n = 5, 6, ..., 16, which are obtained by exhaustive searches. To obtain the best code, we use a regular convolutional code whose weight spectrum is equivalent to that of each punctured convolutional code. We search these equivalent codes for the best one. Next, we present a method that searches for good punctured convolutional codes by partial searches. This method searches the codes that are derived from rate 1/2 original codes obtained in the first method. By this method, we obtain some good punctured convolutional codes relatively faster than the case in which we search for the best codes.
- A Construction of High Rate Punctured Convolutional Codes, Hiroshi Sasano, Sen Moriya, 2012 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA 2012), 2012 INTERNATIONAL SYMPOSIUM ON INFORMATION THEORY AND ITS APPLICATIONS (ISITA 2012), 662 - 666, 2012 , RefereedSummary:We consider two methods that construct high rate punctured convolutional codes. First, we present best high rate R = (n - 1)/n punctured convolutional codes, for n = 5, 6, ... , 16, which are found by exhaustive searches. To obtain the best code, we use a regular convolutional code whose weight spectrum is equivalent to that of each punctured convolutional code. We search these regular equivalent codes for the best one. Next, we present a method that searches for good punctured convolutional codes by partial searches. This method searches the codes that are derived from R = 1/2 original codes obtained in the first method. By this method, we obtain some good punctured convolutional codes that have superior performance compared with that of the best codes.
- Dynamic snapshot algorithm and partial rollback algorithm for internet agents, Sen Moriya, Tadashi Araragi, Electronics and Communications in Japan, Part III: Fundamental Electronic Science (English translation of Denshi Tsushin Gakkai Ronbunshi), Electronics and Communications in Japan, Part III: Fundamental Electronic Science (English translation of Denshi Tsushin Gakkai Ronbunshi), 88(12), 43 - 57, Dec. 2005 , RefereedSummary:This paper considers an Internet agent system in which a tremendous number of agents operate, frequently appearing and disappearing, and discusses the fault-tolerant algorithm. Application of the snapshot algorithm to the agent system is considered. The snapshot algorithm is used to view the whole situation (snapshot) of the distributed system. The snapshot algorithm of Chandy and Lamport [2] is considered as a representative snapshot algorithm, in terms of the high efficiency and the simplicity of the procedure. It is not practical, however, to apply their snapshot algorithm to the distributed agent system in which a tremendous number of agents operate. From such a viewpoint, this paper extends the idea of Chandy and Lamport's algorithm and proposes a subsnapshot algorithm, in which the snapshot is taken among the agents who are in the causal relation, through message exchange and agent creation. Then, an efficient rollback algorithm is proposed, which is based on the snapshots taken by the subsnapshot algorithm. In the general rollback algorithm utilizing the snapshot, all agents must roll back. In contrast, in the rollback algorithm proposed in this paper, it suffices that only some agents should roll back. © 2005 Wiley Periodicals, Inc.
- Wait-free linearizable distributed shared memory, S Moriya, K Suda, M Inoue, T Masuzawa, H Fujiwara, IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS, IEICE TRANSACTIONS ON INFORMATION AND SYSTEMS, E83D(8), 1611 - 1621, Aug. 2000 , RefereedSummary:We consider a wait-free linearizable implementation of shared objects on a distributed message-passing system. We assume that the system provides each process with a local cluck that runs: at the same speed as global time and that all message delays are in the range [d - u, d] where d and u. (0 < u less than or equal to d) are constants known to every process. We present four wait-free linearizable implementations of read/write registers on reliable and unreliable broadcast models. We also present two wait-free linearizable implementations of general objects on a reliable broadcast model. The efficacy of an implementation is measured by the worst-case response time for each operation of the implemented object. Response times of our wait-free implementations of read/write registers on a reliable broadcast model is better than a previously known implementation in which wait-freedom is not taken into account.
- Optimal wait-free clock synchronization protocol on a shared-memory multi-processor system, M Inoue, S Moriya, T Masuzawa, H Fujiwara, DISTRIBUTED ALGORITHMS, PROCEEDINGS, DISTRIBUTED ALGORITHMS, PROCEEDINGS, 1320, 290 - 304, 1997 , RefereedSummary:We consider wait-free clock synchronization protocols on an in-phase shared-memory multi-processor system. A wait-free clock synchronization protocol guarantees that, for a fixed k, local clocks of processors which have been working consecutively for at least k pulses are synchronized. Such k is called synchronization time. The best previous result with regard to the synchronization time is O(n(2)), where n is the number of processors, In this paper, we present a wait-free synchronization protocol with synchronization time O(n), and also show that this synchronization time is asymptotically optimal.

- Construction of High Rate Convolutional Codes (2), Hiroshi SASANO, Sen MORIYA, The 41th Symposium on Information Theory and its Applications, 157, 160, 2018 12
- Construction of High Rate Convolutional Codes, Hiroshi SASANO, Sen MORIYA, The 40th Symposium of Information Theory and its Applications, 436, 439, 2017 11
- Faster Wait-free Randomized Consensus with an Oblivious Adversary for MRSW Register Model (ディペンダブルコンピューティング), 守屋 宣, 井上 美智子, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 278, 13, 18, 2016 10 27 , http://ci.nii.ac.jp/naid/40020991421
- Checkpointing and Rollback Using Lamport Clocks for Hybrid P2P Systems, 守屋 宣, 電子情報通信学会技術研究報告 = IEICE technical report : 信学技報, 116, 17, 1, 8, 2016 04 22 , http://ci.nii.ac.jp/naid/40020818966
- Construction of High Rate Punctured Convolutional Codes via Identical Codes, Hiroshi SASANO, Kana KIKUCHI, Sen MORIYA, The 38th Symposium of Information Theory and its Applications, 2015 11 , 10.1587/transfun.E98.A.1579
- Compute Searches for High Rate Punctured Convolutional Codes by Using Dual Codes, Kana Kikuchi, Sen Moriya, Hiroshi Sasano, The 37th Symposium of Information Theory and its Applications, 553, 558, 2014 12
- A Method for Constructing High Rate Punctured Convolutional Codes by Using Dual Codes (II), KIKUCHI Kana, MORIYA Sen, SASANO Hiroshi, IEICE technical report. Information theory, 114, 138, 143, 148, 2014 07 , http://ci.nii.ac.jp/naid/110009947019
- A Method for Constructing High Rate Punctured Convolutional Codes by Using Dual Codes, Kana Kikuchi, Sen Moriya, Hiroshi Sasano, The 36th Symposium of Information Theory and its Applications, 388, 393, 2013 11
- A Study on Constructing High Rate Punctured Convolutional Codes by Using Dual Codes(II), KIKUCHI Kana, MORIYA Sen, SASANO Hiroshi, IEICE technical report. Information theory, 113, 153, 89, 94, 2013 07 , http://ci.nii.ac.jp/naid/110009778281
- A Study on Constructing High Rate Punctured Convolutional Codes by Using Dual Codes, Kana Kikuchi, Sen Moriya, Hiroshi Sasano, The 35th Symposium of Information Theory and its Applications, 246, 250, 2012 11
- A Construction of Very High Rate Convolutional Codes, Hiroshi SASANO, Sen MORIYA, The 34th Symposium of Information Theory and its Applications, 201, 204, 2011 12
- Evalution of Object Distribution Method using Low Traffic Quorum System for Mobile Ad Hoc Network, MICHIBATA Shinnosuke, MORIYA Sen, HIGUCHI Masahiro, 全国大会講演論文集, 72, 0, 1-491, 1-492, 2010 03 08 , http://ci.nii.ac.jp/naid/110008105572
- Load balancing algorithm based on probabilistic grid quorum system for ad hoc networks, 守屋 宣, 水井 啓太, 回路とシステム軽井沢ワークショップ論文集, 21, 677, 682, 2008 04 , http://ci.nii.ac.jp/naid/40016083706
- Efficient Algorithm by Grid Based Quorum for Distributed Mutual Exclusion, MORIYA Sen, IPSJ SIG Notes, 103, 77, 84, 2005 11 , http://ci.nii.ac.jp/naid/110003503017
- Wait-Free Algorithm for Asynchronous Resource Trade between Internet Agents, MORIYA Sen, ARARAGI Tadashi, IEICE technical report. Theoretical foundations of Computing, 101, 708, 71, 78, 2002 03 , http://ci.nii.ac.jp/naid/110003191978
- Dynamic Snapshot Algorithm and Partial Rollback Algorithm for Internet Agents, MORIYA Sen, ARARAGI Tadashi, IEICE technical report. Theoretical foundations of Computing, 101, 44, 17, 24, 2001 05 , http://ci.nii.ac.jp/naid/110003191890
- Wait-Free Linearizable Implementation of a Distributed Shared Memory (Algorithm Engineering as a New Paradigm), Inoue Michiko, Suda Katsuro, Moriya Sen, Masuzawa Toshimitsu, Fujiwara Hideo, RIMS Kokyuroku, 1120, 78, 87, 1999 12 , http://ci.nii.ac.jp/naid/110000163912
- Wait-Free Linearizable Implementation of a Distributed Shared Memory, S. Moriya, K. Suda, M. Inoue, T. Masuzawa, H. Fujiwara, Technical Report of IEICE, COMP99-37, 99, 288, 45, 52, 1999 09 06 , http://ci.nii.ac.jp/naid/110003191796
- Wait-Free Linearizable Implementation of a shared Object, SUDA Katsuro, MORIYA Sen, INOUE Michiko, MASUZAWA Toshimitsu, FUJIWARA Hideo, IEICE technical report. Theoretical foundations of Computing, 98, 562, 9, 15, 1999 01 , http://ci.nii.ac.jp/naid/110003180307
- Optimal Self-Stabilizing Wait-Free Clock Synchronization Protocol on a Shared-Memory System, MORIYA Sen, INOUE Michiko, MASUZAWA Toshimitsu, FUJIWARA Hideo, IEICE technical report. Theoretical foundations of Computing, 98, 137, 31, 38, 1998 06 , http://ci.nii.ac.jp/naid/110003191663
- Optimal Wait-free Clock Synchronization Protocol on a Shared-memory Multi-processor System, MORIYA Sen, INOUE Michiko, MASUZAWA Toshimitsu, FUJIWARA Hideo, IEICE technical report. Theoretical foundations of Computing, 96, 487, 85, 92, 1997 01 , http://ci.nii.ac.jp/naid/110003191438