Tauberian theorems for the weighted mean method of summability of sequences of fuzzy numbers

This thesis essentially consists of three chapters. In the first chapter, the dawn of fuzzy logic, its aim and advantages are shortly mentioned. Also, informations concerning studies which have done by several researchers with respect to fuzzy set, fuzzy numbers and its sequences and works which will be done in this thesis are given. In the second chapter, firstly basic definitions and theorems related with fuzzy number and its sequences are included. Later, development process of classical Tauberian theory is mentioned, basic definitions and notations which are going to be used throughout the thesis related with summability theory are given and finally some classical Tauberian conditions are investigated. In the third chapter, how the concept of sequences of fuzzy numbers has been applied to the weighted mean method of summability is explained, necessary and sufficient conditions for regularity of this method are given and some Tauberian theorems for this method are proved.