Minimum about fuzzy logic
Fuzzy generalization procedure

There is a possible solution by employing fuzzy logic. Binary logical variables will be replaced by fuzzy variables, which can take any values between zero and one, and the truth thereof represents the degree of fire risk. Furthermore, there will be introduced such logical operations that generalize the fundamental logical operators AND, OR, and NOT. Each sensor corresponds to one fuzzy variable. The assignment of logical value to the value of voltage signal received from the sensor (the simplest case of fuzzification) depends on our judgment – it could be a mere linear normalization of the range, or a linear dependence in the active area with limitation on both sides of the range, or a general non-linear dependence.

Fig. 6.6: Possible behaviors of the logical function for continuous fire sensor