Majalah Ilmiah UNIKOM

Vol.10 No. 1

68

H a l a m a n

are interval type-2 fuzzy systems described

by Gaussian primary membership function

with uncertain means, denoted as

Figure

3. Gaussian interval type-2 fuzzy membership

function with uncertain means

where

is the uncertain

a1,…,n

b1,…,m

rules and

is the standard deviation.

There are two kinds of type-2 sets. First is a

gaussian type-2 fuzzy set, which the

membership grade of every domain point is

a Gaussian type-1 set contained in [0,1].

Second is an interval type-2 fuzzy set which

the membership grade of every domain

point is a crisp set whose domian is some

interval contained in [0,1]. Figure 3. shows

gaussian interval type-2 fuzzy membership

function with uncertain means

The upper membership function is defind as

where

And lower membership function is defind as

Fuzzy Inference System

Fuzzy inference mechanism applies the

fuzzy reasoning on the rules in the rule base

in order to derive a mathematically

reasonable output or conclusion which

represents the problem conditions best.

Fuzzy inferences in antecedent using

algebraic product, is denoted as

and

Figure 4. shows Fuzzy inference illustrative

example of the simplified case with two

input variable.

The interval value of the consequent

is

, where

and

and

denote the lower and

b

rule.

denotes the center (mean) of

and

denotes the spread of

.

Muhammad Aria