Abstract: In this paper, the short comings of the usual optimization theory is analysed, the background for bringing forward satisficing criteria is discussed, and current researches on the satisfactory degree is described. In view of the limitation of the present research work in the satisficing domain, some concepts of the generalized satisfactory degree are defined and characterized, and the multi objective optimization theory based on the generalized satisfactory degree theory are explored and applied to the optimization design of transportation capability of railway-network. The analysis of the example shows that the theory and method in this paper is effective and applicable.

Key words: satisfactory optimization, satisfactory degree, railway transportation, multi-objective optimization, wagon flow path