  Identifying graphs with extremal properties is an extensively studied topic
in spectral graph theory. In this paper, we study the log-concavity of a type
of iteration sequence related to the $\alpha$-normal weighted incidence
matrices which is presented by Lu and Man for computing the spectral radius of
hypergraphs. By using results obtained about the sequence and the method of
some edge operations, we will characterize completely extremal k-graphs with
the smallest spectral radius among bicyclic hypergraphs with given size.
