%0 Journal Article %T Convexity Invariance of Fuzzy Sets under the Extension Principles %A Dong Qiu %A Weiquan Zhang %J Journal of Function Spaces and Applications %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/849104 %X We discuss the convexity invariance of fuzzy sets under the extension principles. Particularly, we give a necessary and sufficient condition for a mapping to be an inverse *-convex transformation, and also obtain some sufficient conditions for a mapping to be an *-convex transformation. Two applications are given to illustrate the obtained results. Finally, we give some applications of the main results to the hyperstructure convexity invariance of type 2 fuzzy sets under hyperalgebra operations, and to the convexity invariance of fuzzy numbers under basic arithmetic operations. %U http://www.hindawi.com/journals/jfsa/2012/849104/