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08
2025/07
Ramsey number and bipartite Ramsey number of double stars
For positive integers n,m, the double star S(n,m) is the graph consisting of the disjoint union of two stars K_{1,n} and K_{1,m} together with an edge joining their centers. Finding monochromatic copies of double stars in edge-colored complete graph and complete bipartite graphs has attracted much attention. The k-color Ramsey number and bipartite Ramsey number of S(n,m) are denoted by r(S(n,m);k) and r_{bip}(S(n,m);k), respectively. To the best of our knowledge, little is known on the exact value of r(S(n,m);k) and r_{bip}(S(n,m);k) when k\ge 3. Using a folklore double counting argument in set system and the edge chromatic number of complete graphs, we prove that if k is odd and n is sufficiently large compared with m and k, then \[r(S(n,m);k)=kn+m+2.\] Applying the Turán argument in the bipartite setting, we prove that if k=2 and n\ge m, or k\ge 3 and n\ge 2m, then \[br(S(n,m);k) = kn + 1.\] In this talk we will discuss the main ideas of our results.This is joint work with Jake Ruotolo (Harvard University) and Gregory DeCamillis (University of Waterloo).
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04
2025/07
Women and Mathematics: A Feminist and Historical Perspective
Recently, the young Chinese female mathematician Wang Hong has attracted widespread attention. This development is part of a broader historical trajectory that began with the emergence of feminism in the 19th century. In this talk, we introduce some famous female mathematicians and a feminist perspective into the history of mathematics, explore how mathematics became a male-dominated discipline over time, and whether—and how—women’s contributions have been overlooked or marginalized throughout history.
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04
2025/07
家政学院人才招聘暨青年学者论坛（二）
陈红森（上海师范大学）：《性别与政治：近代中国家政教育论争》；贺鹏丽（华中师范大学）：《渐进均衡与间断革新：新中国托育师资政策变迁探析》；刘赛（复旦大学）：《感知解说质量对游客博物馆体验的影响研究》；周坤（河北农业大学）：《现象学视角下再论乡村性本质》。
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04
2025/07
CUMCM2025参赛指南
全国大学生数学建模竞赛（CUMCM）是由中国工业与应用数学学会主办、教育部支持的A类学科竞赛，自1992年起每年举办。作为全球规模最大的数学建模赛事，2024年吸引近20万学生参与。2025年赛事将于9月4日启动。为了让参赛学生从理念到实践全面认识数学模型和数学建模竞赛，报告从数学模型概念出发，对数学模型和数学建模进行了全方位的阐述。并结合历史参赛数据和题目，对数学建模竞赛活动进行了详细剖析并提出参赛建议。旨在让参赛学生建立正确的模型观，正确引导同学实现“一次参赛，终身受益”。
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03
2025/07
数学科学学院人才招聘暨青年学者论坛
11:20-11:40 封婧雪（西蒙菲莎大学）高级贝叶斯建模方法及其在公共卫生中的应用探索14:10-14:30 李健松（北京工业大学）可局部化齐性空间上的逼近与积分14:40-15:00 罗丛（中国科学技术大学）k-临界图的最大边数15:10-15:30 王姗（山东大学）无穷维随机系统的最优控制问题15:50-16:10 杨雪阳（山东大学）无穷时间区间上的随机系统的最优控制问题16:20-16:40 赵路明（波尔多大学）p-进Galois表示和（phi,tau)-模
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06
2025/07
中国式现代化理论与实践研讨会
1.深入研讨中国式现代化的理论精神与实践成果；2.研讨推进河北省人文社会科学重点研究基地建设高质量发展。
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06
2025/07
新世纪以来中国城市职能特征及演变
新世纪以来中国城市职能特征及演变
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11
2025/07
肠道菌源酶:代谢性疾病干预的新路径
肠道菌源酶:代谢性疾病干预的新路径
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04
2025/07
Bourgain techniques for low regularity error estimates
Standard time-stepping techniques require a regularity constraint on the initial data $u_0$ for dispersive equations. We introduce a class of low regularity integrators for problems where certain constraints are not satisfied. Moreover, when the regularity is critically low ($u_0\in H^s$ with $s\leq d/2$), the classical stability argument based on Sobolev spaces does not hold. We have developed a discrete Bourgain framework that overcomes this problem. In this talk, I will use several different dispersive models to summarize how these techniques are applied.
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04
2025/07
Explicit K-symplectic methods for nonseparable non-canonical Hamiltonian systems
We propose efficient numerical methods for nonseparable non-canonical Hamiltonian systems which are explicit, K-symplectic in the extended phase space with long time energy conservation properties. They are based on extending the original phase space to several copies of the phase space and imposing a mechanical restraint on the copies of the phase space. Explicit K-symplectic methods are constructed for two non-canonical Hamiltonian systems. Numerical tests show that the proposed methods exhibit good numerical performance in preserving the phase orbit and the energy of the system over long time, whereas higher order Runge–Kutta methods do not preserve these properties. Numerical tests also show that the K-symplectic methods exhibit better efficiency than that of the same order implicit symplectic, explicit and implicit symplectic methods for the original nonseparable non-canonical systems.
