对区间二型模糊集的EKM降型法的改进

二型模糊集的质心计算称为降型，目前的降型方法大多计算成本较高，其中EKM (Enhanced Karnik-Mendel)法可计算区间二型模糊集的质心。然而，由于EKM算法中求取切换点的初始化方法还不完善，计算时间较长，使其在实际应用中受到一定限制。对此，提出一种新的改进EKM法，对原有方法进行了两处改进：更改切换点的初始化条件和改进查找切换点的方法。所提出的方法可实现向上和向下搜索，计算量大大减小，降型更有效。仿真结果验证了新的改进EKM法的有效性。

Improvement of enhanced Karnik-Mendel algorithm for interval type-2 fuzzy sets

Type reduction is the work of computing the centroid of a type-2 fuzzy set. At present, most of type reduction
methods have high computational cost. The enhanced Karnik-Mendel(EKM) algorithm can compute the centroid of an
interval type-2 fuzzy set efficiently. However, the initialization of the switch point in the EKM algorithm is not a good
one, and the computation time is long, which makes a limit on the application in real system. In view of these problems,
a novel improved EKM algorithm is developed for improving the EKM algorithm. The proposed algorithm provides two
improvements on the EKM algorithm. Firstly, the initialization conditions of switch points are changed. Then, the method of
searching for switch points is improved, in which can search upward and downward. The number of computations involved
is greatly reduced and type reduction can be done much more efficiently. The simulation results show the effectiveness of
the proposed method.