Risk evaluation model for radiation protective countermeasures based on fuzzy entropy weight
On the basis of establishing a risk assessment index system, a model for assessing the risk of radiation protective countermeasures is proposed by introducing a fuzzy mathematics method and entropy weight theory, and the risk order of the radiation protective countermeasures is ranked by their entropy weight coefficients, which solves the decision problem of uncertain and fuzzy indexes in the risk assessment index system and could provide the decision-making basis for commanders in the process of nuclear accident rescue. The illustrative case study shows that the model could use the inherent information of the indexes adequately, and makes risk assessment for radiation protective countermeasures more reasonable, practicable and scientific.
Application of Bayes decision technique for intermediate and late phase for optimizing emergency to nuclear accidents
The application of Bayes decision technique for intermediate and late phase for optimizing emergency to nuclear accidents is introduced. The principle of Bayes and its application in optimization decision making are illustrated.
Transformation from availability expression to failure frequency expression
The problem of computing the system's Failure Frequency is reduced to the problem of computing its Availability. This is performed by a transformation operator. However, the existing transformation operator is not practical because its transformation time increases exponentially with system size. To overcome this difficulty, this paper proposes a new method of transforming the Availability expression of a system into the corresponding Failure Frequency expression of the system. This method is based on a matrix approach using a 2 /spl times/ 2 matrix consisting of 0, Availability, and Failure Frequency in an appropriate manner. This transformation also enables algorithms for computing the Availability of a system to be transformed into algorithms for computing its Failure Frequency by replacing parameters and operations with matrix parameters and operations. The computation time after transformation is linear with respect to the original Availability algorithm. This implies that the problems of computing other well-known reliability measures including, Availability, Unavailability, MTBF, MTTR, MCT, Failure Rate, Failure Rate, and Failure Frequency, are reduced to only the Availability computation problem.