Page 319 - Materials Chemistry, Second Edition

318 15. Barriers identification and prioritization

greater than zero, then the i-th factor can be recognized as a causal factor, and if it is less than
zero, then, it can be recognized as an effect factor.

Step 5: Determining the weight of each influential factor
The weight of the i-th factor can be determined by Eqs. (15.20), (15.21).
q ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi
2 2
0
ω ¼ R i + C j + R i C j (15.20)
i
ω 0
ω i ¼ i (15.21)
N
X
ω 0
i
i¼1
where ω i represents the relative weight of the i-th factor.
Step 6: Drawing the IRM (influence relation map)
The IRM is drawn according to ω i , which represents the relative importance of the i-th fac-
tor and R i C j , which shows the category (causal factor or effect factor) of the i-th factor.

15.4 Results and discussion

In order to determine the initial influence matrix, the interdependence relation matrix was
firstly determined by using “O” and “X”:

(1) “O” was used to describe the influence of the i-th factor on the j-th factor if the i-th factor
does not exert the j-th factor;
(2) “X” was used to describe the influence of the i-th factor on the j-th factor if the i-th factor
exerts the j-th factor.

For instance, there are three influential factors including lack of advanced technologies
(T 1 ), lack of special research and development (R&D) funding (EC 3 ), lack of
awareness and perceptions (SM 1 ), and lack of supporting policies and regulations (SM 2 ),
having influences on high energy consumption (T 2 ), thus, “X” was put in the corresponding
cells of the second column, as presented in Table (15.2). After these, the fuzzy best-worst
method was employed to determine the relative influences of the barriers on each barrier
(Step 1).
Step 1: Establishing the initial influence matrix X.
A total of nine experts on seawater desalination was invited to participate in a focus group
meeting; three of them are full professors whose research mainly focuses on sustainable de-
salination technologies, three of them are senior researchers with PhD degrees who have
worked on developing desalination processes for more than 10years, and three of them
are senior engineers who have worked in the national seawater desalination factories for
more than 10years. Taking the elements in the second column (the relative influences of
T 1 ,EC 2 ,SM 1 and SM 2 on T 2 ) as an example:

Substep 1: Determine the most influential factor and the least influential factor.