Then proved that it is one kind of convexity between KUC and KSC,and as one concept,KDC is the dual concept of KSS better than KSC is.

• 然后证明了它是介于KUC和KSC之间的一种凸性。 进而说明了KDC作为KSS的对偶性质比KSC更为恰当。