based on the point of view of geometrical representation of an intuitionistic fuzzy set, we take into account all three parameters describing intuitionistic fuzzy set, propose a kind of new method to calculate correlation and correlation coefficient of intuitionistic fuzzy sets which is similar to the cosine of the intersectional angle in finite sets and probability space, respectively. further...

module over a ring is a general mathematical concept for many examples of mathematicalobjects that can be added to each other and multiplied by scalar numbers.in this paper, we consider a module over a ring as a universe and by using the notion of reference points, we provide local approximations for  subsets of the universe.

the concept of an $l$-bornology is introduced and the theory of $l$-bornological spacesis being developed. in particular the lattice of all $l$-bornologies on a given set is studied and basic properties ofthe category of $l$-bornological spaces and bounded mappings are investigated.

a novel method to compute the stability region in power system transient stability analysis is presented. this method is based on the set analysis. the key to this method is to construct the hamilton-jacobi-isaacs (hji) partial differential equation (pde) of a nonlinear system, using which we can compute the backward reachable set by applying the level set methods. the backward reachable set of...

many textbooks include semantically related words and sometimes teachers add synonyms, antonyms, etc. to the words in order to present new vocabulary items without questioning the possible effects. this study sought to investigate the effect of teaching vocabulary through synonym, semantically unrelated, and hyponym sets based on higa’s (1963) proposed continuum. a total of 120 iranian intermed...