In factory operations, the multi operation and multi index system is very common. In such a system, if we want to implement the quality control and diagnosis, we must consider the following two points, i.e. the influence on the preceding operation to the succeeding operation and the correlation among indices. Since these two points exist simultaneously, it makes the problem more complex. We need to use the new multivariate diagnosis theory with two kinds of quality proposed by Prof. Zhang Gongxu in 1996 to solve such complex problem. This paper presents its fundamental principles with practical applications which agree with the theory pretty well.
