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Vol: 51(65) No: 1 / March 2006      

Fuzzy J-K Flip-Flops Based on Various Classic and Non-Associative Norms
Rita Lovassy
Institute of Microelectronics and Technology, Budapest Tech, Hungary, Budapest, Hungary, e-mail: lovassy.rita@kvk.bmf.hu
Laszlo T. Koczy
Institute of Information Technology, Mechanical and Electrical Engineering, Széchenyi István University, Győr, Hungary, Győr, Hungary, e-mail: koczy@sze.hu


Keywords: fuzzy logic, non-associative operations, fuzzy flip-flop.

Abstract
JK flip-flops are the elementary digital circuits providing sequential features/memory functions. The definitive equation of these units is well known in both the minimal disjunctive and the minimal conjunctive forms. As fuzzy connectives do not possess all axiomatic properties of their Boolean counterparts, if each operation in these equations is substituted by a corresponding fuzzy operator, two non-equivalent definitions are obtained, which were named reset type and set type fuzzy flip-flops (F3) by Hirota et al. when first introducing the concept of F3. There are many alternative possibilities to extend the idea of digital flip-flop, first of all based on classic (Zadeh-type), algebraic and other connectives. This paper gives an overview of the behavior of some of the most famous F3-s by presenting the definitions and examining the graphs of the inner state Q for several typical state value combinations. It is clearly shown that set and reset type definitions do not match in any case. In the next part a pair of non-associative operators is introduced, referring to an earlier definition by Fodor and Kóczy and the properties of this F3 are also discussed. The surprising fact is presented that the graphs of the two different flip-flops are identical. It is also proven that the two definitive forms are identical in the mathematical sense.

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