Notes on Finite Geometries and the Construction of PBIB Designs Ⅱ. Some PBIB Designs with Two Associate Classes Based on the Symplectic Geometry over Finite Fields

We follow the notation and terminology of the previous note （Ⅰ）. We take the set B of all m-dimensional, totally isotropic subspaces B, B, …, Bwith respect to the nonsingular alternate matrix K as the set of blocks and the set V of all one-dimensional subspaees V, V, …, V（note that they are all totally isotropic!） as the set of treatments. We define n=1 if the one-dimensional subspace V（treatment） is contained