Liu X.-C.,Unit 95899 |
Zhu L.-S.,Unit 95899 |
Zhang W.,Unit 92857
Binggong Xuebao/Acta Armamentarii | Year: 2013
A new fuzzy inference-based wartime spares demand forecasting method is presented for the uncertainty and stage-relativity of the spares demand during multi-stage war, in which expert forecasting value and Markov forecasting value are combined. The result is obtained according to the Mamdani-style inference mechanism and defuzzification. The fuzzy set of demand is defined by linguistic variable naturally, which is introduced in Markov forecasting to describe the system state directly. The validity of the method is illustrated by an example.
Miao X.-H.,Unit 92857 |
Wang X.-R.,Unit 92857 |
Jia D.,Unit 92857 |
Jin G.-Y.,Harbin Engineering University |
Pang F.-Z.,Harbin Engineering University
Jisuan Lixue Xuebao/Chinese Journal of Computational Mechanics | Year: 2012
It is much valuable to find a method for predicting the middle and high sound radiation characteristics of big and complex structures such as ships and airplanes. The Perfectly Matched Layer (PML) method is introduced and applied successfully to predict the underwater sound radiation characteristics of complex double cylindrical shell structures. Compared to the conventional coupled finite element method and boundary element method (FEM/BEM), it can reduce the fluid field model to more than 11/15 of the original. The ring frequency and the damping are two important factors for the practical cylindrical structures, and according to their effects to the vibration transmission, a modeling method for the big and complex cylindrical structures is present. Numerical results showed that the PML method and the modeling method are valid and can be applied to deal with engineering problems.