Applied Mathematics Seminar——Geometric Quasi-Linearization (GQL) for Bound-Preserving Schemes
报告人：吴开亮（南方科技大学）
时间：2023-11-07 13:00-14:00
地点：理科一号楼1418
摘要：Solutions to many partial differential equations satisfy certain bounds or constraints. For example, the density and pressure are positive for equations of fluid dynamics, and in the relativistic case the fluid velocity is upper bounded by the speed of light, etc. As widely realized, it is crucial to develop bound-preserving numerical methods that preserve such intrinsic constraints. Exploring provably bound-preserving schemes has attracted much attention and has been actively studied in recent years. This is however still a challenging task for many systems especially those involving nonlinear constraints. Based on some key insights from geometry, we systematically propose a novel and general framework, referred to as geometric quasilinearization (GQL), which paves a new effective way for studying bound-preserving problems with nonlinear constraints. The essential idea of GQL is to equivalently transform all nonlinear constraints into linear ones, through properly introducing some free auxiliary variables. We establish the fundamental principle and general theory of GQL via the geometric properties of convex regions and propose three simple effective methods for constructing GQL. We apply the GQL approach to a variety of partial differential equations and demonstrate its effectiveness and advantages for studying bound-preserving schemes, by diverse challenging examples and applications which cannot be easily handled by direct or traditional approaches.
个人简介：吴开亮，南方科技大学数学系/深圳国际数学中心/深圳国家应用数学中心 副教授、博导。2011年获华中科技大学学士学位；2016年获英国威廉希尔公司博士学位；2016-2020年先后在美国犹他大学和俄亥俄州立大学从事博士后研究；2021年1月加入南方科技大学。致力于研究偏微分方程数值解、机器学习与数据驱动建模、计算流体力学等，研究成果发表在SIAM Review、SIAM J. Numer. Anal.、SIAM J. Sci. Comput. 、Numer. Math.、M3AS、J. Comput. Phys.、天体物理期刊ApJS、Phys. Rev. D、人工智能期刊IEEE Trans. Artif. Intell.等。曾获中国数学会计算数学分会 优秀青年论文奖一等奖（2015）和中国数学会 钟家庆数学奖（2019）；入选国家高层次人才计划（青年项目）；主持国家自然科学基金面上项目和重大研究计划培育项目、深圳市优秀人才（杰青）项目。
