Soft Computing and Its Applications, Volume One

Fuzzy Implications and Fuzzy If-Then Models 405

fast(x) =

FIGURE 9 Values of linguistic variable speed.

In many practical applications we normalize the domain of inputs and use the fol-

lowing type of fuzzy partition (See Figure 10).

FIGURE 10 A possible fuzzy partition of [-1, 1].

Here we use the abbreviations:

• NB Negative Big, [NM] Negative Medium,

• NS Negative Small, [ZE] Zero,

• PS Positive small, [PM] Positive Medium, and

• PB Positive Big.

4.4 LINGUISTIC TRUTH VALUE

Let, Truth = {Absolutely false, Very false, False, Fairly true, True, Very true, and Ab-

solutely true}.

We may dene the membership function of linguistic terms of truth as: ...