报告题目1：Exact Algorithms for Optimally Finding Partially Disjoint Shortest Paths

报告人：张晓岩教授，南京师范大学

报告时间：2025年12月5日（周五）19:00

报告地点：腾讯会议 399 921 655

报告摘要：We focus on the development of exact algorithms for finding partially disjoint shortest paths in a graph. The aim is to optimize the process of identifying paths that share some edges while maintaining the shortest possible length. The proposed algorithms leverage advanced techniques in graph theory and combinatorial optimization to ensure efficiency and accuracy in solving this complex problem.

报告人简介：张晓岩，南京师范大学数学科学学院及数学研究所教授、博士生导师、中国科学院深圳先进技术研究院数字所高性能计算中心客座研究员，国家重大人才领军计划入选者，江苏省“六大人才高峰”高层次人才入选者，江苏省智库青年人才计划入选者，主要从事组合优化与高性能图计算以及统计学习和人工智能数学解释的研究工作，研究成果发表在《SIAM J. Computing》、《SIAM J. Scientific Computing》、《SIAM J. Discrete Math》、《IEEE Transactions on Information Theory》、《IEEE Transactions on Computers》等国际著名期刊上，著有英文学术论著2部、译著1部等。

报告题目2：The sandpile model on generalized wheel graph

报告人：鲁卢副教授，中南大学

报告时间：2025年12月10日（周三）10:00

报告地点：腾讯会议 213 480 785

报告摘要：For two graphs  and $H$, their \emph{join}, denoted $G \vee H$, is the graph obtained from the disjoint union of $G$ and $H$ by adding all edges between them. The \emph{generalized wheel graph} $C_m \vee I_n$ is the join of a cycle $C_m$ and an independent set $I_n$ of $n$ vertices. In this talk, I will introduce a recent work on the Abelian sandpile model (ASM) on $C_m \vee I_n$ with the sink vertex chosen from $I_n$. The results are threefold. First, we give a complete characterization of the recurrent configurations of the ASM on $C_m \vee I_n$ for all $m \geq 3$ and $n \geq 1$. Second, we construct an explicit bijection between the recurrent configurations of the ASM on $C_m \vee I_n$ restricted to the cycle $C_m$ and the spanning trees of polygonal chain graphs; this bijection consequently yields an enumeration of the spanning trees of the latter. Finally, we provide a complete characterization and the exact enumeration of all minimal recurrent configurations. By the known duality, this also gives a complete characterization and the exact number of all maximal superstable configurations on $C_m \vee I_n$.

报告人简介：鲁卢，中南大学数学与统计学院副教授，博士生导师。2019年毕业于新疆大学，导师是黄琼湘教授，主要研究方向为代数图论和图谱理论，主持国家自然科学基金2项、湖南省自然科学基金1项，在《European J. Combin.》、《Adv. in Appl. Math.》、《Electron. J. Combin.》、《J. Algebraic Combin.》、《Discrete Math.》、《Linear Algebra Appl.》等国际期刊上发表论文50余篇。

邀请人：离散数学研究所