In this study, the dynamic response of a multiconnected floating solar panel system with a vertical pontoon were studied under various scenarios. First, a floating solar panel pontoon is modeled by combining nine single-unit vertical cylinders (arranged in parallel, horizontally and vertically, 3 m apart from each other). Each cylinder will be considered a rigid body, and they are connected to each other with a frame, so that they can oscillate together. Each floating solar panel pontoon was connected to a steel pipe, and a hinged connector was attached to the connecting point of each steel pipe, while it was fixed at each pontoon. In this study, as a floating solar panel system, a 10 × 10 system was adopted at a water depth of 50 m. Furthermore, a catenary mooring system with steel wire rope was installed to enhance its station-keeping capability. As an environmental load, wave excitation force, under normal operating and extreme conditions, was considered. To confirm the dynamic behavior of the system, a connector boundary condition sensitivity test was conducted under a 0° heading (west to east). It has been proven that an unexpected dynamic response along the sway, roll, and yaw directions is observed in the hinged connector case, due to the second generated moment caused by the movement of the facilities. Furthermore, judging from extreme simulation results, the larger the external environmental loading, the greater the dynamic response of the system, due to amplified wave excitation forces. Finally, under the multiple mooring line failure scenario, the dynamic response of the system is significantly amplified, due to the loss of mooring tension, except for the roll response.

Research Findings: This study examined the learning effects of collaborative group work under heterogeneous group composition among 5-year-old children, especially in terms of their social skills. To this end, the study utilized an experimental research design wherein 3 groups of differently composed dyads and a group of students who worked alone completed classification and perspective-taking tasks. The dyads consisted of a low-ability child and either a socially advanced, an intellectually advanced, or a (both) socially and intellectually advanced peer. First, we found that children with high ability and those with low ability in collaborative dyads had higher learning gains than singletons. This finding supports the benefits of collaborative learning for experts as well as novices and the effectiveness of mixed-ability groupings for young children’s learning. Second, we observed that low-ability children working with socially advanced partners, even partners with low cognitive ability, showed significantly greater improvement in the perspective-taking task than those working with a cognitively advanced but socially less skilled partner. We discuss the findings in terms of the relation between executive function and social competence and emphasize the value of social skills in cognitive development. Practice or Policy: We propose suggestions for teaching practice and further research.

A cable-stayed bridge is widely adopted to construct long-span bridges. The deformation of cable-stayed bridges is relatively larger than that of conventional bridges, such as beam and truss types. Therefore, studies regarding the monitoring systems for cable-stayed bridges have been conducted to evaluate the performance of bridges based on measurement data. However, most studies required sufficient measurement data for evaluation and just focused on the local response estimation. To overcome these limitations, Structural Responses Analysis using a Limited amount of Multi-Response data (SRALMR) was recently proposed and validated with the beam and truss model that has a simple structural behavior. In this research, the structural responses of a cable-stayed bridge were analyzed using SRALMR. The deformed shape and member internal forces were estimated using a limited amount of displacement, slope, and strain data. Target structural responses were determined by applying four load cases to the numerical model. In addition, pre-analysis for initial shape analysis was conducted to determine the initial equilibrium state, minimizing the deformation under dead loads. Finally, the performance of SRALMR for cable-stayed bridges was analyzed according to the combination and number of response data.

High-voltage transmission towers consist of structures that are designed to avoid the risk of electric shock and prevent the risk of collapse. Hence, for efficiency, they are generally designed as high-rise towers. The main tower posts are the primary structural members that resist loads under various load conditions. Therefore, the contribution of the secondary members to securing the stiffness and strength of the main posts by reducing the effective buckling length is an important one. However, we lack detailed secondary member design criteria. In this study, we observed the structural effects of the horizontal members and braces on the torsional stiffness, elastic buckling strength, and load-carrying capacity of a transmission tower using various structural analysis methods, including linear elastic, eigenvalue, and geometric nonlinear and inelastic analyses, under governing load combinations. According to the analytical results, it is the brace spacing rather than the horizontal members that substantially affects the structural performance. Therefore, we can minimize the number of horizontal members if we erect sufficient brace members. If the brace spacing is wide, then the horizontal members should be erected to create K bracing, thereby enhancing the buckling resistance of the main posts.

The structural deformed shape (SDS) is considered an important factor for evaluating structural conditions owing to its direct relationship with structural stiffness. Recently, an SDS estimation method based on displacement data from a limited number of data points was developed. Although the method showed good performance with a sufficient number of measured data points, application of the SDS estimation method for on-site structures has been quite limited because collecting sufficient displacement data measured from a Global Navigation Satellite System (GNSS) can be quite expensive. Thus, the development of an affordable SDS estimation method with a certain level of accuracy is essential for field application of the SDS estimation technique. This paper proposes an improved SDS estimation method using displacement data combined with additional slope and strain data that can improve the accuracy of the SDS estimation method and reduce the required number of GNSSs. The estimation algorithm was established based on shape superposition with various combined response data (displacement, slope, and strain) and the least-squares method. The proposed SDS estimation method was verified using a finite element method model. In the validation process, three important issues that may affect the estimation accuracy were analyzed: effect of shape function type, sensor placement method, and effectiveness of using multi-response data. Then, the improved SDS estimation method developed in this study was compared with existing SDS estimation methods from the literature. Consequently, it was found that the proposed method can reduce the number of displacement data required to estimate rational SDS by using additional slope and strain data. It is expected that cost-effective structural health monitoring (SHM) can be established using the proposed estimation method.