数学科学学院学术报告[2025] 033号

(高水平大学建设系列报告1055号)

报告题目：A threshold dislocation dynamics method

报告人：秦晓雪 讲师（上海大学）

报告时间：2025年05月08日（周四）上午10:30—11:30

报告地点：汇星楼501室

报告内容：We propose an efficient threshold dynamics method for dislocation dynamics in a slip plane. We show that this proposed threshold dislocation dynamics method is able to give two correct leading orders in dislocation velocity, including both the O(logε) local curvature force and the O(1) nonlocal force due to the long-range stress field generated by the dislocations, where ε is the dislocation core size. This is different from the available threshold dynamics methods in the literature which only give the leading order local velocities associated with mean curvature or its anisotropic generalizations of the moving fronts. We also propose a numerical method based on spatial variable stretching to overcome the numerical limitations brought by physical settings in this threshold dislocation dynamics method. Specifically, this variable stretching method is able to correct the mobility and to rescale the velocity, which can be applied generally to any threshold dynamics method. We validate the proposed threshold dislocation dynamics method by numerical simulations of various motions and interaction of dislocations.

报告人简历：秦晓雪博士，现任上海大学数学系讲师、硕士生导师，上海市海外高层次人才。2020年8月毕业于香港科技大学数学系，获理学博士学位；2020年9月-2022年8月在香港科技大学数学系从事博士后研究。主要研究方向为晶体材料中缺陷的数学建模与高效数值算法。近年来，在计算数学与科学计算领域取得了一系列创新性成果，相关研究发表在SIAM Journal on Multiscale Modeling and Simulation (SIAM MMS)、Journal of Scientific Computing (JSC)、Communications in Computational Physics (CICP)等期刊。

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邀请人：张露婵

　　　 数学科学学院

　　　　　　　　　　　2025年5月7日