Root mean square error criterion using operational deflection shape curvature for structural damage detection

Detection of structural damages using the vibration test data has been investigated by many researchers in the last decades. Identification of the defect in the early stages can prevent the unpredicted failure of structure. For beam-like structures, curvature techniques, e.g., mode shape curvature and flexibility curvature have been applied to localize the damage. In this paper, root mean square error using operational deflection shape curvature is used for damage detection. Differential Quadrature Method (DQM) is implemented to obtain the curvatures of the operational deflection shape. To demonstrate the effectiveness of method, the finite element model of a cantilever beam is used. The model is excited and the responses are measured in the simulated test. Enhanced frequency domain decomposition (EFDD) is used to extract the modal parameters. Also Mass change method is used to scale the mode shapes through which the scaled ODS parameters are computed. Using the RMSE the location of the damage is identified. The results show that this approach is more effective than the previous method

The investigation of relationship between behavioral and decisional procrastination with personality characteristics among students of Tehran Universities

Introduction: The present study was carried out with the aim to investigate the relationship between behavioral and decisional procrastination with personality characteristic among students of Tehran Universities.  Methods: the number of samples in this research includes 400 students (114 female and 286 male) from Tehran universities that selected using random cluster-multistage sampling and completed behavioral, decisional procrastination and five factor personality questionnaire. Data were analyzed using descriptive statistics, independent t-test and Pearson correlation.  Results: Data indicated that the most prevalence of behavioral and decisional procrastination was between Shahid Beheshti and Tabatabaie universities respectively. On the other hand, procrastination was related positively to neuroticism and negatively to consciousness, extraversion and agreeableness. Also, there were no relationship between procrastination and openness.  Conclusion: Considering the positive relationship between procrastination and neuroticism and negative relationship with consciousness, extroversion and agreeableness, attention to personality characteristics can reduce procrastination and in turn, improve engagement in educational activities. Declaration of Interest: None.