On January 7, the 2022 "Master Lecture Series" jointly sponsored by the School of Mathematical Sciences and the Institute of Applied Systems Analysis of Jiangsu University started on schedule at Cloud. The invited guest speaker was Professor Yihong Du, a member of the Australian Academy of Sciences from the University of England, who is an international expert in the field of nonlinear analysis, partial differential equations and their applications. More than one hundred teachers and students attended this lecture, including Prof. Zhengze Zhang from Xi'an Jiaotong University, Prof. Jianhua Wu from Shaanxi Normal University, Prof. Zhanbing Bai from Shandong University of Science and Technology, Prof. Guowei Dai from Dalian University of Technology, Prof. Renhao Cui from Harbin Normal University, Prof. Baoqiang Yan from Shandong Normal University, Associate Prof. Kui Li from Zhengzhou University, Prof. Zhitao Zhang and Prof. Jun Wang from Jiangsu University. The report was hosted by Dean Zhitao Zhang of the Academy of Mathematical Sciences.

Professor Yihong Du gave a wonderful lecture entitled "The Stefan problem with a source term in n-space", which mainly introduced the Stenfan problem with a source term in high-dimensional space. Firstly, he introduced the history of the free boundary problem and explained the connection between the free boundary problem and the reaction diffusion and biomathematical population problems, then he introduced the regularity problem of the high-dimensional asymmetric free boundary problem and the related weak solution definition, and gave his main results and research methods in the case of bounded initial region and unbounded initial region, finally, Professor Du introduced his research on the Λ-type free boundary problem. Finally, Professor Du introduced his latest research results on Λ-type free boundary problems.

    In the report, Prof. Du explained the profound connection between free boundary and other branches of mathematics, reflecting his profound mathematical skills. His informative, well-organized and rigorously argued report attracted great interest and attention from the students and teachers present.

   After the presentation, Prof. Du gave patient and detailed answers to the questions that everyone was concerned about. President Zhitao Zhang made a concluding speech on the lecture.