A kind of universal constructor method for buffer operator

In this paper, according to the data sequence of system behavior {x(k)} k=1 n and a set of data {y(k)} k=1 n satisfying y(n) = x(n), the authors prove that there always exists a buffer operator D satisfying XD={x(k)d} k=1 n, which can provide a specific constructor method of buffer operator. Finally, the axiom of invariable trend is proposed to add in the axiom systems of buffer operator.