讲座内容：

A (simple, undirected) graph is half-arc-transitive if its full automorphism group acts transitively on
its vertex set and edge set, but not on its arc set. A graph is called a bi-Cayley graph over a group H if
it admits H as a group of automorphisms acting semiregularly and with two orbits on the vertex set. In
this talk, I will introduce some results on half-arc-transitive bi-Cayley graphs.