12 Evaluating Disinfection Techniques of Water Treatment …
109
Table 12.2 Linguistic Fuzzy
Scale
Linguistic scale for importance weight Triangular fuzzy scale
Very high (VH)
(0.75, 1, 1)
Important (H)
(0.50, 0.75, 1)
Medium (M)
(0.25, 0.50, 0.75)
Low (L)
(0, 0.25, 0.50)
Very low (VL)
(0, 0, 0.25)
12.5 Results and Discussion
The application of VIKOR model in evaluation and ranking of different water disinfection technique gives accurate result due to the fact that consistent ranking output is
obtained. And the importance weights of the parameters defuzzified using the Yager
index to obtain a single value out of the triangular fuzzy numbers and normalized for
the use of the VIKOR technique. Then the best ( f
∗
i ) and the worst values ( f
−
i ) sets of
the alternatives based on each criterion have been calculated as shown in Table 12.3.
And the utility (S j ) and the regret (R j ) measures of each alternative have been
calculated as shown in Table 12.4.
Lastly the ranking result of this analysis obtained based on the (Q i ) index, which
is a combination of the S i and R i indexes. The alternative with a lower (Q i ) is the
better alternative and the ranking result is presented in Table 12.5.
Table 12.5 depicts the ranking result of different water disinfection methods
based on the considered criteria’s. Results show that, the UVR is the best alternative amongst the others with a valuable differences and CD is the least alternative.
Table 12.5 depicts the evaluation and ranking of different water disinfection techniques depending on the applied weight and criteria. The analysis result revealed that
UVR is the best and CD is the least preferable disinfection methods. This is because
UVR requires minimum MOC, has higher reliability, highest PRE, no unwanted
Table 12.3 The positive ( f ∗
i ) and the negative ideal points ( f
−
i ) of the alternatives
Alternatives/criteria CC OMC OS PRE SR RS RF Error! not a valid link
f ∗
i
5
3
9
9
4
9
7
1
f
−
i
9
8
4
2
8
5
4
8
Table 12.4 S j and R j
indexes of the disinfection
methods
Alternatives
S i
R i
UVR
0.75
0.75
CR
3.712857143
0.92
CM
4.659142857
0.92
OZ
3.910857143
0.92
CD
4.974857143
0.92
109
Table 12.2 Linguistic Fuzzy
Scale
Linguistic scale for importance weight Triangular fuzzy scale
Very high (VH)
(0.75, 1, 1)
Important (H)
(0.50, 0.75, 1)
Medium (M)
(0.25, 0.50, 0.75)
Low (L)
(0, 0.25, 0.50)
Very low (VL)
(0, 0, 0.25)
12.5 Results and Discussion
The application of VIKOR model in evaluation and ranking of different water disinfection technique gives accurate result due to the fact that consistent ranking output is
obtained. And the importance weights of the parameters defuzzified using the Yager
index to obtain a single value out of the triangular fuzzy numbers and normalized for
the use of the VIKOR technique. Then the best ( f
∗
i ) and the worst values ( f
−
i ) sets of
the alternatives based on each criterion have been calculated as shown in Table 12.3.
And the utility (S j ) and the regret (R j ) measures of each alternative have been
calculated as shown in Table 12.4.
Lastly the ranking result of this analysis obtained based on the (Q i ) index, which
is a combination of the S i and R i indexes. The alternative with a lower (Q i ) is the
better alternative and the ranking result is presented in Table 12.5.
Table 12.5 depicts the ranking result of different water disinfection methods
based on the considered criteria’s. Results show that, the UVR is the best alternative amongst the others with a valuable differences and CD is the least alternative.
Table 12.5 depicts the evaluation and ranking of different water disinfection techniques depending on the applied weight and criteria. The analysis result revealed that
UVR is the best and CD is the least preferable disinfection methods. This is because
UVR requires minimum MOC, has higher reliability, highest PRE, no unwanted
Table 12.3 The positive ( f ∗
i ) and the negative ideal points ( f
−
i ) of the alternatives
Alternatives/criteria CC OMC OS PRE SR RS RF Error! not a valid link
f ∗
i
5
3
9
9
4
9
7
1
f
−
i
9
8
4
2
8
5
4
8
Table 12.4 S j and R j
indexes of the disinfection
methods
Alternatives
S i
R i
UVR
0.75
0.75
CR
3.712857143
0.92
CM
4.659142857
0.92
OZ
3.910857143
0.92
CD
4.974857143
0.92