A Pythagorean Fuzzy Multigranulation Probabilistic Model for Mine Ventilator Fault Diagnosis

Algorithm 1

Input A PF multigranulation probabilistic approximation space over two universes , along with the information of frequency ranges for a mine ventilator.

Output The determined fault type.

Step 1. Calculate maximal membership degrees and minimal membership degrees .

Step 2. Determine the risk coefficient , and calculate variable membership degrees .

Step 3. Determine the thresholds and , and calculate the lower approximation and the upper approximation of in terms of .

Step 4. Determine the corresponding positive region , negative region and boundary region with respect to and .

Step 5. Confirm the determined fault type for the faulty mine ventilator according to fault diagnosis rules for mine ventilators , and .