Dry storage systems are one of the storage methods for spent nuclear fuel used in many countries that operate nuclear power plants. To ensure the safe storage of spent nuclear fuel, dry storage systems are designed to maintain radiation shielding, thermal management, and subcritical and mechanical integrity. In addition, these systems must be able to withstand earthquakes, tornadoes, floods, extreme temperatures, and other operating and design-based accident conditions. In order to develop a model with safety and economic feasibility by analyzing various dry storage systems, a vertically dry storage module was proposed, and evaluations were performed on safety evaluation along with design requirements. As a result of the evaluation, all of the safety design requirements were met. This evaluation’s results can be used as basic data for the detailed design of the dry storage module to proceed with further research, including the preparation of a safety analysis report and experimental verification for licensing applications.

This study investigated how welding affects the thermal deformation of square cells produced for casks, which are dry storage containers for spent nuclear fuel. We aimed to minimize structural deformation by utilizing STS316L as the material for the square cells. We explored a method of subdividing the square cells and joining them through butt welding. Keeping the upper plate thickness constant, GTA butt welding was conducted while varying the column’s wall thickness, followed by measurement with a laser vision sensor. The heat conduction and thermal strain were then calculated using a finite element analysis (FEM). Both experimental and analytical results confirmed that there was significant thermal deformation in the cases of thick-walled columns due to variations in heat conduction distribution, with the resulting deformation patterns depending on thickness.

Automated welding processes have become increasingly critical in the shipbuilding, automotive, and aerospace industries. Precise weld seam tracking is essential for reliable automated welding, as torch misalignment causes weld defects and significant variations in bead geometry. In this study, fillet welding experiments using flux-cored arc welding (FCAW) were performed under 15 conditions comprising five torch offset levels (−2, −1, 0, +1, +2 mm; positive values denote displacement toward the vertical plate) and three welding speeds (6.0, 7.5, and 9.0 mm/s). Twelve characteristic points were extracted from three bead cross-section zones—the vertical penetrated zone, horizontal penetrated zone, and bead surface zone—and predicted using a nonlinear exponential regression model. All regression coefficients were statistically significant at the 95% confidence level. Piecewise cubic Hermite interpolation (PCHIP) was subsequently applied to reconstruct smooth two-dimensional bead profiles from the predicted feature points. Quantitative validation of the primary leg-length parameters (L_V and L_H) yielded low prediction error (RMSE below 0.7 mm and MAE below 0.5 mm) across all tested conditions. The proposed algorithm runs in under 1 ms and is therefore well-suited for real-time integration into seam-tracking control systems.