Entropy increase principle in isolated system, which is deduced from the discussion of Clausius entropy and Boltzmann entropy, has further deduced entropy principle in open system as well.

• 通过对克劳修斯熵、玻耳兹曼熵的讨论，得到熵的本质和孤立系统的熵增加原理，并把孤立系统的熵增加原理推广为开放系统的熵原理。