Distributional model of yearly investment for torpedo based on Vague sets

Development cost of torpedo weighs lightly in the whole life cycle cost, while the most life cycle cost is determined in the developing phase. So the study of the development cost can improve the important reference for the decision-maker. Based on the Vague sets, the entropy of Vague sets is suggested, then a distributional model of the yearly investment for torpedo based on the entropy of Vague sets is put forward. An example indicates that this model has practical value.