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This article presents a new approach to processing data in identifying and evaluating defects of structures with deformation measurement signals. By using sensitive characteristics observed in the old statistical parameters such as mean values, variances, and standard deviations, we propose three new parameters including kurtosis, skewness of signals, and statistical density function. In addition, we apply cumulative function in statistical and data analysis. High reliability and accuracy of the present approach has been verified through 38 bridges with over 300 span structures in Ho Chi Minh City (HCMC). Furthermore, we have conducted experiments with a small-scale model at the Laboratory of Applied Mechanics (LAM) to compare computational results with ones derived from practical data. Obtained results show promising applicability of sensitive parameters extracted from statistical features in identifying and evaluating defects in structures. [ABSTRACT FROM AUTHOR]

This article presents a novel concept for an Origami-inspired shading device based on dynamic daylight that can be used to improve the daylight performance of a target building and reduce the energy consumption for the building. The daylight performance is evaluated based on the Leed v4 (Leadership in Energy and Environmental Design) daylight criterion. The proposed shading device is experimented in an office located in Ho Chi Minh City, Vietnam, where there is a tropical monsoon climate being hot and humid by the year. To investigate the effectiveness of the proposed design in acting as a sun shading system for the office, we consider eight cases corresponding to eight directions which are South, North, East, West, South-East, North-East, South-West, and North-West. An automatic simulation optimization procedure is developed by combining a daylight simulation tool called DIVA and an optimization method called Balancing Composite Motion Optimization (BCMO). BCMO is used to find the optimal design for the proposed kinetic shading device which will help the building to improve daylight performance. It must be noted that the proposed framework is not necessarily tied to any particular optimization tool or type of building. The results show that the proposed kinetic device has outstanding performance as it helps the building to achieve 2, 3 points in Leed v4 for four different directions, including North, North-East, South, North-West. • An automatic simulation-based optimization approach is investigated through BCMO and DIVA. • Two comparing designs are used to validate the effectiveness of the proposed design. • The proposed kinetic shading device helps building to achieve Leedv4 certification in four directions. • The proposed kinetic shading device could be used as a general sunshade solution in many design situations. • The proposed design could save energy of the building from 25% to 46%. [ABSTRACT FROM AUTHOR]

• A viscoelastic approach into structural damage detection and diagnosis is proposed. • The present method exploits amplitude and frequency of vibration signals and determines their relation with mechanical parameters in detecting structural changes. • Two new parameters namely elastic module (E) and viscous coefficient (C 0) are suggested. This article addresses a novel approach to diagnose a structure's damage based on changes in the mechanical parameters of materials. Firstly, we integrate a viscoelastic model into structural damage detection and diagnosis. Accordingly, this model defines materials' mechanical characteristics via two parameters namely elastic module (E) and viscous coefficient (C 0). While Hooke's model is linear, the viscoelastic is non-linear, and therefore, it reflects real situation more precisely. Secondly, we exploit amplitude and frequency of vibration signals and determines their relation with mechanical parameters in detecting structural changes. Based on theoretical analysis and experimental results, our study reveals more effective and general than previous ones. The simultaneous monitoring of structural change using different parameters allow the research to collect more appropriate data compared to previous studies. The results derived from this research were adopted in monitoring health of Saigon bridge over the period of 15 years. Via more than 100 sensors permanently attached to the bridge, the measured signals enabled the evaluation of the structure's operation status. This experimental result shows suitability among the proposed theoretical approaches, and thereby forms a basis to forecast damages of complex structures. [ABSTRACT FROM AUTHOR]