Review : week 7

  1. Distinguish between classical logic and fuzzy logic. Your answer should include "membership function", "crisp", "fuzzy" and "set".
  2. Define with examples, fuzzification, rule evaluation, de-fuzzification
  3. Write down the three Zadeh operators. Illustrate each with a diagram.
  4. Here is the truth table for classical logic
    A	B	A and B		A or B		not A
    --	--	-----------	--------	-------
    0	0	0		0		1
    0	1	0		1		1
    1	0	0		1		0
    1	1	1		1		0
    
    Reproduce this table using the Zadeh operators for (A B) = (0.3 0.7).
  5. Define the extension principle and its implications for the connection of classical logic to fuzzy logic. Using the Zadeh operators, demonstrate the extension principle for row 2 or the above table. Show all calculations
  6. Draw the following membership function for
    1. (a b crisp)= ( -50,50,0.1) and
    2. (a b crisp)= ( -50,50,1)
    (defun crisp (x a b crisp)
      "Return a point in a sigmoid function centered at (a - b)/2"
      (labels ((as100 (x min max)
    	     (+ -50 (* 100 (/ (- x min) (- max min))))))
        (/ 1 (+ 1 (exp (* -1 (as100 x a b) crisp))))))
    
    Mark on the x-axis the key points of the function.
  7. Draw the following membership function for (x a b c) = (x 10 20 30).
    (defun fuzzy-fun1 (x a b c) 
      (max 0 (min (/ (- x a) (- b a))
    	      (/ (- c x) (- c b)))))
    
    Mark on the x-axis the key points of the function.
  8. Draw the following membership function for (x a b c d) = (x 10 20 30 60).
    (defun fuzzy-fun2 (x a b c d)
      (max 0 (min (/ (- x a) (- b a))
    	      1
    	      (/ (- d x) (- d c)))))
    
    Mark on the x-axis the key points of the function.
  9. On one plot, draw the following membership functions for (dist 'close) (dist 'medium) (dist 'far)
    (defun dist (d what)  
      (case what
        (range    '(close medium far))
        (close     (fuzzy-triangle   d -30 0 30))
        (medium    (fuzzy-trapezoid  d 10 30  50 70))
        (far       (fuzzy-grade      d 0.3  50 100))
        (t         (warn "~a not known to dist" what))))
    
    Mark on the x-axis the key points of these functions.