Diagnosis of Eye Diseases using Intuitionistic Fuzzy Soft SetsS. JayakumarDepartment of Mathematics, A.V.V.M. Sri Pushpam College, Poondi 613 503, Thanjavur (Dt).Tamil Nadu, India.Email: jayakumar_s1957@yahoo.co.in A. Hari GaneshDepartment of Mathematics, Ponnaiyah Ramajayam Institute of Science & Technology (PRIST) University, Vallam 613 403. Thanjavur. Tamil Nadu, India. Email: hari.math3@gmail.comAbstract: Theconceptoffuzzysoftset isoneoftherecenttopics developedfor dealingwiththe uncertainties present in most of our real life situations. The parameterization tools of fuzzy soft set theory enhance the flexibility of its applications to different problems.In this paper a diagnostic method is evolved for the diagnosis of eye diseases using intuitionistic fuzzy soft sets.Keywords:SoftSet,FuzzySoftSet, IntuitionisticFuzzySoftSet, Intuitionistic Fuzzy Number, Ranking of Intuitionistic Fuzzy Numbers.AMS Subject Classification: 03B52, 03E721. Introduction: For many of the common diseases, medical diagnosis involves procedures that are only approximate to arrive at the correct diagnosis [2]. The medical diagnosis procedure for the determination of various types of diseases is generally observedbyusingtheinherent propertyoffuzzysettheory andfuzzylogic. Theessenceoffuzzylogicistoprovidea linguistic approach with better approximation. Most of the problems of real life have various uncertainties. Traditional mathematical tools are unable to solve uncertain problems.There are theories viz.theories of probability, theory of evidence, fuzzy set, intuitionistic fuzzy set, vague set for dealing with uncertainties. These theories have their own difficulties. The reason for there difficulties is inadequacy of parameterization tool of the theories. Moldtsovproposedthe novel concept of soft set theory in his pioneering paper. Later on authors like Maji et al. have further studied the theory of soft sets and introduced the concepts of fuzzy soft set and intuitionistic fuzzy soft set [6]. In this paper, we suggested a procedure for the diagnosis of eye diseases which based on intuitionistic fuzzy soft sets. 2. Preliminaries:Inthissectionwepresent abrief summaryof the definitionofthesoft sets, fuzzysoft setsandintuitionistic fuzzy soft sets which are useful for subsequent discussion. Definition 1Let U be an initial universe set and E be the set of parameters. Let P(U) denotes the power set of U. A pair (F, E) is called a soft set over U where F is mapping given byP(U) E : F .Definition 2 Let U be an initial universe set and E be the set of parameters. LetE A . Apair(F, A) iscalledfuzzysoft set overU where F is a mapping given byUI A : F , where IU denotes the collection of fuzzy subsets of U. Definition 3 Let U be an initial universe set and E be the set of parameters. Let IFU denotes the collection of all intuitionistic fuzzy subsets of U. let E A . A pair (F, A) is called intuitionistic fuzzy soft set over U, where F is mapping given by UIF A : F . 2.1.Arithmetic operation on Intuitionistic fuzzy numbers Definition 1An IFS U} (x))/x V (x), {(x, AA A is called IF-normal, if there exist at least two points x0, x1U such that 1 ) (x v 1, ) (x 1 A 0 A , it is easily seen that given intuitionistic fuzzy set A is IF-normal if there is at least one pointthatsurelybelongstoAandatleastonepointwhich does not belong to A. Definition 2 AnIFS U} (x))/x V (x), {(x, AA A ofthereallineis called IF-convex, if [0,1] R, x , x2 1 ) (x v ) (x v ) )x (1 ( v) (x ) (x ) )x (1 ( 2 A 1 A 2 1 A2 A 1 A 2 1 A + +Thus Ais IF-convexif its membershipfunctionis fuzzy convex and its non membership function is fuzzy concave. 1Definition 3An IFS U} (x))/x V (x), {(x, AA A of the real line is called an intuitionistic fuzzy number (IFN) if a) A is IF normal, b) A is IF-convex, c)Ais upper semi continuous and vA is lower semi continuous,d)1} (x) / v X {x AA< Definition 4A is a triangular intuitionistic fuzzy number with parameters [5]. 3 3 2 2 1 1b a a b a b and denoted by 2 2 3 3 2 2 1 1b a ); b , a , a , b , a , (b A In this case we will give

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