3.5. Weights determination
After the hierarchical structure has been established, anther questionnaire on the basis of the propose structure is formulated. The questionnaire surveys are used to compare pairs of elements of each level with respect to each element in the next higher level. We use 7-point scale, and that will be easy to answer. To avoid getting subjective results, in each questionnaire, the interviewee will be asked to select the lower value, mean value, and upper value to each question. Then fuzzy AHP methods are adopted relied on the membership function. The questionnaires also triangular target on the evaluated experts mentioned in Section 3.4. To integrate different experts' opinions, the following formulas are applied