Workshop on Combinatorics and its applications
时间:2020年1月4日
报到时间:2020年1月4日
报到地点:bat365官网登录555
报告地点:bat365官网登录145
联系人: 周岳, zhouyue@csu.edu.cn, 13374151106
报告题目1: Derived Matroids of Matroid Representations
报告人: 王岁杰副教授（湖南大学）
报告时间: 1月4日下午2:00--3:00
报告摘要: In this talk, we will explore the derived matroids and derived sequences of represented matroids. Firstly, the derived sequences are classified into three types: finite, cyclic, and divergent, which are completely characterized. Secondly, we determine all representable matroids whose derived matroids and dual matroids are isomorphic. Finally, as applications, the flats of the derived matroid give a classification on the translation deformations of hyperplane arrangements.
个人简介: 王岁杰博士本科就读于武汉大学, 硕士毕业于北京大学, 2010年在香港科技大学取得博士学位, 其后在香港科技大学和台湾中央研究院从事博士后研究, 于2013年加入湖南大学, 现为湖南大学bat365官网登录副教授, 博士生导师. 研究领域涉及超平面配置, 拟阵理论, 杨表理论及其组合计数等, 相关科研成果发表于J. Combin. Theory Ser. A, J. Combin. Theory Ser. B, Adv. in Appl. Math., Math. Proc. Camb. Phil. Soc等杂志.
报告题目2: Arithmetic Properties of Overpartitions
报告人: 张文静助理教授 （湖南大学）
报告时间: 1月4日下午3:00--4:00
报告摘要: In this talk, I will prove several inequalities for $\overline{p}(n)$. Moreover, the higher order Tur\'{a}n inequalities of $\overline{p}(n)$ can also be determined. After that, I will establish the generating functions for the ranks differences of overpartitions modulo $6$ and $10$, and obtain some inequalities between the ranks of overpartitions modulo $6$ and $10$. In light of these generating functions, some relations between mock theta functions and the ranks of overpartitions modulo $6$ and $10$ can also be found.
个人简介: 张文静, 湖南大学助理教授, 博士毕业于天津大学应用数学中心. 论文发表在J. Number Theory等期刊上.
报告题目3: Adaptive Re-shrink of p-Shrinkage Thresholding Operator for Nonconvex Sparsity Function in Background Modeling
报告人: 商琨助理教授 （湖南大学）
报告时间: 1月4日下午4:00-5:00
报告摘要: In common wisdom of background modeling, conventional shrinkage operator (e.g., soft thresholding or hard thresholding) is the foremost tool to attain a target sparsity of the singular value vector of the video background. Meanwhile, p-shrinkage thresholding operator, which is considered more adaptive, has shown its advantages in various compression sensing tasks, while seldom produces satisfying performancein dealing with the matrix based problems including background modeling. So, in this paper, aim at establishing a more effective shrinkage operator, we explore potential derivations of p-shrinkage thresholding operator by using a re-shrink strategy and thus propose a soft p-shrinkage thresholding operator for estimating the principal component of the video background. Then, supported by our purified dictionary learning for background details and spatiotemporal continuity constraint for foreground objects, we establish a joint estimation problem for background modeling task, and solve it by proposing a soft p-shrinkage iterative algorithm (SpSA). Experimental results have shown that, when compared against current state-of-the-art techniques, SpSA achieves comparable and often superior performance in terms of F-measure scores in most cases.
个人简介: 商琨, 2018年毕业于天津大学应用数学中心, 目前的研究方向是计算机视觉中的视频分析问题, 已在IEEE TIFS, TFS, Information Fusion, Information Sciences, Computational Optimization and Applications, Neurocomputing等期刊发表论文10余篇.
