题目：Improved Bounds and Optimal Constructions of Locally Repairable Codes

主讲人：方伟军

时间：2023年7月13日（周四）上午10:00

地点：文理大楼723

报告摘要：

      Locally repairable codes (LRCs) as a new coding scheme have given more rise to the system performance and attracted a lot of interest in the theoretical research in coding theory. In this talk, we first of all derive an improved and general upper bound on the code length of Singleton-optimal LRCs with minimum distanced= 5, 6, some known constructions are shown to exactly achieve our new bound, which verifies its tightness. Moreover, we obtain a complete characterization for Singleton-optimal LRCs with r = 2 and d = 6. Furthermore, we employ the well-known line-point incidence matrix and Johnson bounds for constant weight codes to derive tighter upper bounds on the code length. To the best of our knowledge, this is the best bound on the code length of optimal (n, k, 6; 2)-LRCs until now.

个人简介：

方伟军研究员2019年博士毕业于南开大学陈省身数学研究所，2019-2021年于清华大学深圳国际研究生院从事博士后工作；2021年9月起就职于山东大学网络空间安全学院。主要研究方向为代数编码及其在量子纠错码、分布式存储编码等前沿课题中的应用。在TIT、TCOM、DCC、FFA、CCDS以及ISIT、ITW等信息论与编码理论期刊与会议发表二十余篇论文。目前主持1项国家自然科学青年基金，1项省自然科学青年基金，作为学术骨干参与2项国家重点研发计划，入选山东省泰山学者青年专家计划，获得山东大学齐鲁青年学者。