• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.6
• /
• pp.8-14
• /
• 2022

In this study reports experiments were conducted to determine the quality of weld beads of different materials, Al and Cu. Among the lasers used to make battery cells for electric vehicles, non-destructive testing was performed using deep learning to determine the quality of beads welded with the ARM laser. Deep learning was performed using AlexNet algorithm with a convolutional neural network structure. The results of quality identification were divided into good and bad, and the result value was derived that all the results were in agreement with 94% or more. Overall, the best welding quality was obtained in the experiment for the fixed ring beam output/variable center beam output, in the case of the fixed beam (ring beam) 500W and variable beam (center beam) 1,050W; weld bead failure was seldom observed. The tensile force test to confirm the reliability of welding reported an average tensile force of 2.5kgf/mm or more in all sections.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.6
• /
• pp.60-66
• /
• 2022

The optimal strain energy function was obtained by comparing the results of the analysis using the strain energy functions obtained by uniaxial tensile and equibiaxial tensile tests on gasket materials used in hydrogen fuel cells, with the results measured using a contact pressure measurement sensor. At this time, even when only the uniaxial tensile test was conducted, Yeoh could obtain the most accurate results even by conducting only the uniaxial tensile test. Using this, an analysis of the cross section of the gasket used in stack confirmed a safe contact pressure and no deformation on the separator. In the future, research will be conducted to verify the gasket durability by reliability evaluation.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.1
• /
• pp.66-72
• /
• 2022

The Mooney-Rivlin second order optimal strain energy function derived through uniaxial tensile test and analysis was applied to a gasket to confirm the internal stress and surface pressure generated during compression. The Taguchi method, a statistical technique, was used to design the optimum shape of the gasket, and through characteristic evaluation, the optimum shape of the gasket was obtained when the reference plane (T: 0.15 mm), contact surface (W: 1.00 mm), and curvature (R: 0.30 mm) were used. It was determined that the optimum shape yields a von Mises stress of 4.83 MPa, and the contact pressure stress is 20.14 MPa, which satisfies breakage and sealing requirements. In the future, we plan to manufacture a jig that can measure surface pressure to conduct comparative verification studies between the test results and analysis results.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.4
• /
• pp.70-76
• /
• 2022

Calcium-phosphate-based bioceramics are promising biomaterials for scaffolds because they can assist in bone regeneration. In this study, a laser sintering deposition system was developed, and 3D hydroxyapatite (HA) scaffolds were fabricated. The main process conditions of the HA scaffolds were laser power, table velocity, and laser focal distance. As the laser power increased, the line width, line height, and layer thickness also increased. Further, the line width, line height, and layer thickness decreased as the table velocity increased. As the laser focal distance increased, the line width increased, but the line height and layer thickness decreased. The fabricated green scaffolds were sintered at 1050 ℃ and 1150 ℃. The sintered scaffolds had a uniform and continuous interconnected shape, with pore sizes ranging from 850 to 950 ㎛ having 53% porosity. The compressive strength of the scaffolds decreased from 0.72 MPa (1050 ℃) to 0.53 MPa (1150 ℃). The biocompatibility of the scaffolds was investigated by analyzing the adhesion of osteoblast-like MG-63 cells cultured on the surfaces of the scaffolds. The results indicate that the scaffold sintered at 1050 ℃ had good mechanical and biological properties compared to that at 1150 ℃.

• Journal of the Korean Society of Manufacturing Process Engineers
• /
• v.21 no.3
• /
• pp.49-55
• /
• 2022

The design of a battery package and a BMS module for applications using seawater rechargeable batteries, which are known as next-generation energy storage devices, is proposed herein. Seawater rechargeable batteries, which are currently in the initial stage of research, comprise primarily components such as anode and cathode materials. Their application is challenging owing to their low charge capacity and limited charge/discharge voltage and current. Therefore, we design a method for packaging multiple cells and a BMS module for the safe charging and discharging of seawater rechargeable batteries. In addition, a prototype seawater rechargeable battery package and BMS module are manufactured, and their performances are verified by evaluating the prevention of overcharge, overdischarge, overcurrent, and short circuit during charging and discharging.

• Food Science of Animal Resources
• /
• v.44 no.2
• /
• pp.269-283
• /
• 2024

Cultured meat is one of the research areas currently in the spotlight in the agricultural and livestock industry, and refers to cells obtained from livestock that are proliferated and differentiated and processed into edible meat. These cell-cultured meats are mainly studied at the lab-scale by culturing them in flasks, and for commercial use, they are produced using scaffolds that mimic cell supports. Scaffolds are broadly divided into fiber scaffolds, hydrogels, and micro-carrier beads, and these are classified according to processing methods and materials. In particular, a scaffold is essential for mass production, which allows it to have appearance, texture, and flavor characteristics similar to meat. Because cultured meat is cultured in a state where oxygen is blocked, it may be lighter in color or produce less flavor substances than edible meat, but these can be compensated for by adding natural substances to the scaffolds or improving fat adhesion. In addition, it has the advantage of being able to express the texture characteristics of the scaffolds that make up the meat in various ways depending on the materials and manufacturing methods of the scaffolds. As a result, to increase consumers' preference for cultured meat and its similarity to edible meat, it is believed that manufacturing scaffolds taking into account the characteristics of edible meat will serve as an important factor. Therefore, continued research and interest in scaffolds is believed to be necessary.

• Journal of Biomedical Engineering Research
• /
• v.37 no.1
• /
• pp.46-52
• /
• 2016

Nanoparticles have been studied as therapeutic and imaging agents for the early detection and cure of cancer, Cancer Theranostics. Nanoparticles were considered to effectively target cancer cells due to Enhanced Permeability and Retention (EPR) effect and most nanoparticles have been evaluated by using spherical shapes. However, the problem that the EPR effect is not so effective for human cancer therapy was recently brought up. Therefore, in this study, we suggest novel discoidal nanoparticles to overcome this problem, focusing on their manufacturing process and quality control. Herein, we demonstrate the improved manufacturing method of discoidal nanoparticles and their potential to apply to MCF 7, human breast cancer treatment.

• Journal of the Korean Society for Precision Engineering
• /
• v.29 no.4
• /
• pp.357-366
• /
• 2012

To schedule a Reconfigurable Manufacturing Cell (RMC), reconfiguration and setting decisions should be made first. Those decisions, together with characteristics of production orders, affect attainable performance of a system. So an integrative approach is required considering all decisions and characteristics rather than dealing with each of them separately. Pallet-fixture allocation, as a decision problem in setting, which determines the number of pallets to be equipped with each fixture type to produce different types of products, has rarely been investigated. In this study, several pallet-fixture allocation rules are proposed including both simple and novel ones. Then system performance is investigated through various combinations of setting and scheduling decisions (rules) for given system configurations and production orders, via simulation. The result shows that one of proposed pallet-fixture allocation rules which considers both configuration and order characteristic outperforms the others, justifying the necessity of an integrative approach in the RMC operation.

• Journal of the Society of Cosmetic Scientists of Korea
• /
• v.36 no.2
• /
• pp.145-150
• /
• 2010

Anoectochilus formosanus, commonly known as "Jewel Orchids", which has been used in traditional folk medicines for feber, pain, and diseases of the lung and liver in Taiwan. We artificially cultured Anoectochilus formosanus plantlet by using the bioreactor culture system for this study from Anoectochilus formosanus. Previously, several studies have been reported on pharmacological activities of lipid-metabolism, hepatoprotective activity, anti-tumor activity and immuno-stimulating effects but other efficacy were not well known as a cosmetic ingredient for skin care. In this study, we investigated the effect of melanogenesis in B16 mouse melanoma cells and lipid droplet accumulation in 3T3-L1 preadipocytes about Anoectochilus formosanus plantlet extract. We report that Anoectochilus formosanus plantlet extract inhibits the cytoplasmic lipid droplet accumulation through adipogenic differentiation of preadipocytes as well as inhibition of tyorsinase activity and melanogenesis. As a result, our findings indicate that Anoectochilus formosanus plantlet extract may be the potential natural ingredient for whitening and slimming cosmetic products.

• Journal of the Korea Society for Simulation
• /
• v.18 no.4
• /
• pp.59-66
• /
• 2009

This has been possible by integration techniques such as very large scale integration (VLSI) and wafer scale integration (WSI). Redundancy has been extensively used for manufacturing memory chips and to provide repair of these devices in the presence of faulty cells. If there are too many defects, the momory has to be rejected. But if there are a few defects, it will be more efficient and cost reducing for the company to use it by repairing. Therefore, laser-repair process is nedded for such a reason and redundancy analysis is needed to establish correct target of laser-repair process. The proposed CRA (Correlation Repair Algorithm) simulation, beyond the idea of the conventional redundancy analysis algorithm, aims at reducing the time spent in the process and strengthening cost competitiveness by performing redundancy analysis after simulating each case of defect.