应闽南师范大学数学与统计学院和福建省粒计算及其应用重点实验室邀请，3月26日下午，宁波大学王小苗教授在砺志楼105作了题为《Difference matrices and their applications》的报告。相关师生聆听了此次报告，报告由曹炜老师主持。

报告中，王小苗教授主要介绍In this talk,we will present some progress on difference matrices. We complete the existence spectrum of a (G,4,1)-difference matrix over any finite abelian group G. Let D_2Hbe the generalized dihedral group of afiniteabelian group H. It is proved that a (D_2H,4,1)-difference matrix exists if and only if H is of even order and H is not isomorphic to Z₄.We showthat if G is a finite abelian group and the Sylow 2-subgroup of G is trivial or noncyclic, then a (G,5,1)-difference matrix exists except for someexceptions.报告结束后，在座的师生就相关研究问题进行了探讨和交流。

王小苗，宁波大学，教授，主要从事组合学与编码理论的研究。主持完成国家自然科学基金项目3项。在J. Combin. Theory Ser. A和IEEE Trans. Inform. Theory等国内外重要刊物上发表学术论文30余篇。