一、报告题目：Phaseless sampling problem in shift-invariant space and time-frequency invariance

二、报告人：李尤发 教授

三、时  间：2026年5月7日（周四）09:30-10:30

四、腾讯会议：405-758-274

报告摘要：In this paper, we investigate the phaseless sampling PS problem for signals in a shift-invariant space (SIS) whose generator satisfies  the complex generalized Haar condition. The unified structure of the   solution set to the PS problem is established. Moreover, the random sampling sequence (having the sampling density (SD)$=3$) is designed for all solutions of an arbitrary signal in such a SIS. Since the solution to the PS problem is not unique, a natural problem is:  what features are shared by all solutions to the PS problem? We focus on such an invariance problem from the perspective of time-frequency analysis.In particular, we show that the phase derivative as well as other features including the  mean   and covariance  of the Fourier transform,  and the  bandwith of a signal are shared by all   solutions to the PS problem. Note that phase derivative is a crucial feature throughout Cohen's class of time-frequency analysis. In this sense, such a time-frequency  invariance result establishes a link between the PS problem and the time-frequency analysis.This is a joint work with Wenchang Sun.

报告人简介：李尤发，博士(后)，教授，博士/硕士生导师；广西数学会常务理事，CSIG图像视频通信专委会委员；大学生数学建模竞赛广西优秀指导教师。2011.09-2012.11，2014.04-07在澳门大学科技草榴社区从事博士后工作；2016-2017年在美国中佛罗里达州立大学访问（导师：韩德广）。从事数据科学、应用调和分析领域的研究，研究方向：1. 信号处理、图像处理；2. 应用计算调和分析、逼近论；3.数学与光学交叉问题；4.机器学习及其在生物信息中的应用。主持面上、青年、地区、数学天元等国家自然科学基金项目5项；广西自然科学基金3项。在《Journal of Functional Analysis》《Applied and Computational Harmonic Analysis》《IEEE Transactions on Information Theory》《IEEE Transactions on Signal Processing》《Journal of Fourier Analysis and Application》《Advances in Computational Mathematics》《Journal of Approximation Theory》《Science China Mathematics》（中英文）等重要期刊上发表论文30多篇。

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