学术报告:2020年12月15日14:30-15:30,上海科技大学-姜嘉骅

发布者:吕小俊发布时间:2020-12-13浏览次数:569

太阳成集团tyc234cc官网邀请专家申请表

  

报告人

姜嘉骅

  

单位

上海科技大学

报告题目

Hybrid Projection Methods   with Recycling for Inverse Problems

报告时间

1215日周二

1430-1530

地点

腾讯会议号:953 280 830

  

邀请人

闫 亮

报告摘要

Iterative hybrid projection   methods have proven to be very effective for solving large linear inverse   problems due to their inherent regularizing properties as well as the   added flexibility to select regularization parameters adaptively. In this   work, we develop Golub-Kahan-based hybrid projection methods that can exploit   compression and recycling techniques in order to solve a broad class of   inverse problems where memory requirements or high computational cost may   otherwise be prohibitive. For problems that have many unknown parameters   and require many iterations, hybrid projection methods with recycling   can be used to compress and recycle the solution basis vectors to reduce the   number of solution basis vectors that must be stored, while obtaining a   solution accuracy that is comparable to that of standard methods. If reorthogonalization   is required, this may also reduce computational cost substantially. In other   scenarios, such as streaming data problems or inverse problems with   multiple datasets, hybrid projection methods with recycling can be used to   efficiently integrate previously computed information for faster and   better reconstruction. Additional benefits of the proposed methods are   that various subspace selection and compression techniques can be   incorporated, standard techniques for automatic regularization parameter   selection can be used, and the methods can be applied multiple times in an   iterative fashion. Theoretical results show that, under reasonable conditions,   regularized solutions for our proposed recycling hybrid method remain   close to regularized solutions for standard hybrid methods and reveal   important connections among the resulting projection matrices. Numerical   examples from image processing show the potential benefits of combining   recycling with hybrid projection methods. 

报告人简介

Dr. Jiahua Jiang is currently   an assistant professor in the School of Information Science and Technology at   ShanghaiTech University. She received her BS degree in University of Science   and Technology of China in 2013. From 2013 to 2018, she received her PhD   degree in Engineering and Applied Science from University of Massachusetts   Dartmouth, under the direction of Prof. Yanlai Chen. From 2018 to 2020, she   did her postdoc with Prof. Julianne Chung in Virginia Tech. In November 2020,   she joined ShanghaiTech University as a tenure-track assistant professor, PI   in the school of Information Science and Technology. Her research   interests include model order reduction, uncertainty quantification,   inverse problem with application in image processing.