讲座内容：

A $k$-regular graph with $v$ vertices is a {\em divisible design graph with parameters} $(v,k,\lambda_1,\lambda_2,m,n)$ if its vertex set can be partitioned into $m$ classes of size $n$ such that any two different vertices from the same class have $\lambda_1$ common neighbours, and any two vertices from different classes have  $\lambda_2$ common neighbours. Divisible design graphs were introduced by H. Kharaghani and first provided by W.H. Haemers, H. Kharaghani and M. Meulenberg. In particular, the authors have proposed several constructions of divisible design graphs using various combinatorial structures. Some new combinatorial constructions of divisible design graphs were later provided by many authors.In this talk, we present two prolific constructions that produce infinite series of divisible design graphs. Using affine designs for these constructions develops ideas of W.D. Wallis, D.G. Fon-Der-Flaass, and M. Muzychuk.