Earticle

With the rapid transition to an aging society, the need for assistive technologies that promote independent indoor living for the elderly and mobility-impaired has become increasingly critical. This study proposes the development of a next-generation powered chair designed to support such independence by compensating for mobility limitations caused by natural aging. The proposed system incorporates two core functionalities: (1) an low seat-lifting mechanism capable of lowering the seat height to 7 cm, and (2) a short-range autonomous driving mode operable in both lowered and lifted positions. The low driving mode enables the user to approach low tables or desks and facilitates effortless transfer to and from low beds or sofas. In the lifted position, the system performs real-time obstacle detection and avoidance within a 3-meter range, preventing falls and collisions while expanding the user’s range of motion—for instance, by allowing access to higher objects or enabling eye-level communication with standing individuals. To realize these functions, a rack-and-pinion lifting mechanism is applied, along with a direct target-point designation method utilizing an LED pointer and a wiper-type screening approach for real-time obstacle avoidance. The design concept, implementation strategy, and validation plan are presented. This research contributes to enhancing the quality of life for elderly users by maximizing their remaining physical capabilities, while simultaneously reducing the physical and emotional burden on caregivers.

The fabrication of curved hull plates is a critical process in shipbuilding, affecting both the structural integrity and hydrodynamic performance of vessels. This study investigates a hybrid forming method that combines induction heating and multi-point press forming to improve the accuracy and efficiency of curved plate production. The forming experiments were performed under various heating and pressing conditions to examine their effects on deformation behavior, forming accuracy, and surface quality. The results indicate that the hybrid forming approach effectively reduces processing time, minimizes spring-back, and enhances the precision of the formed geometry compared with conventional mechanical forming. These findings demonstrate the potential of hybrid forming as an efficient and reliable technique for manufacturing complex hull structures in modern shipbuilding.

This paper was studied to improve the efficiency of big fans through the modification of the impeller shape while maintaining other parameters such as casing geometry(shape), entry and exit diameter, rotation speed, number of blades, flow rate, and static pressure in accordance with the field requirements including the existing installation. Numerical calculation based on semi-empirical formula(SEF) and the methodology of computational fluid mechanics(CFD) were used. It is widely used in the chemical industry, and a large fan with a nominal flow capacity of 510,000 m/h and a static pressure of 11,000 Pa was used as a case study. In this study, the theoretical performance comparison and field measurements of the existing fan and crystal fan geometry designs were conducted. The results of the study showed that the modified geometric design can contribute to reducing the absorption power by up to 135 kW, thereby increasing the fan efficiency by up to 5.87%.

Injection molds, composed of components such as upper and lower cores, mold bases, pins, and cooling channels, serve as the primary tooling for manufacturing plastic products. Despite the often simple geometry of molded products, the configuration and design of mold components remain highly complex, making the technical expertise and accumulated know-how of mold designers essential. However, the mold industry is facing increasing difficulties due to the discontinuation of academic programs dedicated to mold design, the aging of experienced designers, and the lack of incoming skilled personnel. To address these challenges, research on automating mold design has continued, and recent advancements in artificial intelligence (AI) have accelerated efforts to internalize expert knowledge through a variety of computational approaches. In this study, we conducted foundational research aimed at constructing a DT-AX platform capable of handling multiple domains by implementing and modularizing diverse processes within a digital-twin (DT) environment and integrating AI modules specialized for each process. Given the input dimensions of a bottle-cap model (diameter and height), the simplified outer dimensions of a core mold were predicted and subsequently used to generate a 3D model. The resulting STEP file was verified to be compatible with commercial CAD and simulation software. Overall, the results demonstrate the feasibility of implementing an automated mold-design module within a digital-twin environment. Future work will focus on diversifying design variables and increasing geometric complexity to develop modules that more closely approximate real-world mold design.