从BIB设计得到的一个三个结合类的结合方案

AN ASSOCIATION SCHEME WITH THREE ASSOCIATE CLASSES DERIVED FROM A BIB DESIGN

通过组合的方法，以一个已知的ＢＩＢ设计导出了一个三个结合类的结合方案，而且这一结合方案并不能退化为两个结合类的结合方案，这是它的一个特点。基于这一结合方案，文中又得出了若干ＰＢＩＢ设计。

An association scheme with three associate classes from a given BIB design is derived by using the method of combination , and the association scheme does not degenerate to a two-associate-class association scheme, that is a characteristic of the association scheme. Based on the association scheme, a number of PBIB designs are obtained.