Kiselman type semigroups (Volodymyr Mazorchuk, NBSAN York, 24th November 2010)

Abstract: Kiselman semigroups form a class of finite semigroups with origins in convexity theory. In this talk I plan to define a generalization, called Kiselman type semigroups, which are finitely presentable semigroups associated with simple mixed graphs. Examples include both Kiselman semigroups, 0-Hecke monoids and various mixtures. I will try to describe both their combinatorial properties and various representations. This is a joint work with O.Ganyushkin and G.Kudryavtseva.