2.5. Questionnaire survey
Based on the SVA method, different parts should be assessed by a questionnaire among experts in the era of security and dam safety. First of all, the threat should be assessed simultaneously with property assessment. Then the combination of these factors with attractiveness gives the criticality of properties. The consequence is achieved based on the SVA approach. Thus the questionnaires are developed based on four main goals. First is the evaluation of asset values based on the vision of the expert. Secondly, it tried to rank threats, and sequentially investigated the attractiveness of the assets. Finally, the questionnaires help the researchers to rank the probable consequences. Table 4 illustrates these goals with related criteria accordingly. 79 experts work in the field of dam security which 50 of them answered the questionnaires. For the reliability of the questionnaire, the Cronbach Alpha was assessed, which was equal to 0.83. The result showed that the reliability of the questionnaire is in the appropriate range.