• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.9
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• pp.382-389
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• 2019

A novel folding process is proposed using a repeated cold-die forging and annealing to form a sterling silver ring. Sterling silver plate was cut into a doughnut shape, and lattices with 0.43-mm line-width were imprinted on it. The sample was folded by forging using dies with slopes of $45^{\circ}$, $60^{\circ}$, and $75^{\circ}$ and annealing. For comparison, samples were also fabricated without annealing. Strain was identified by measuring the length of lattices. Vernier calipers, a Vickers hardness tester, an optical microscope, and a UV-VIS colorimeter were used to determine the size, hardness, microstructure, and body color. Without annealing, cracks occurred. However, successful deformation was possible when annealing was used. The results of macro strain measurements show that the outer diameter and width decreased, while the inner diameter and thickness increased after the final process. The maximum strain was increased 0.128 toward the parallel direction. The Vickers hardness decreased after annealing and increased after the folding process. The microstructure results showed that the grain size increased after annealing but decreased after folding. The color difference based on the Lab index was under 10 for all processes. Eventually, a doughnut-shaped silver plate was successfully deformed into a ring shape by the folding process.

• Journal of Navigation and Port Research
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• v.48 no.3
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• pp.221-231
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• 2024

The aim of this study was to enhance the safety and care of mental health for seafarer working in passenger ship workspaces. Brightness, color values, and color distribution were investigated with issues and improvement ways identified through seafarers' interviews. Firstly, previous studies, references, current policy, regulations, and accident case studies were reviewed. Color compositions of wheelhouse and engine room of M Ship were then surveyed in the field. Color values of each space were analyzed using a colorimeter. Colormeter analysis of brightness and color measurements in the wheelhouse and engine areas indicated that ceilings, walls, and floors were generally dark, with the engine area being very dark. Regarding color, green and blue were distributed in the ceiling of the wheelhouse and engine area, while red and blue were in the walls and floors of the wheelhouse and engine area. According to interviews with seafarers currently working at engine rooms, they responded about their experience of near miss incidents due to a decrepit indoor environment, a dark working environment, slippery and bright flooring, and stairs that were not suitable for domestic users. Thus, when installing lighting in the future, the brightness of the space should be improved by distinguishing between night and day. A lighting plan considering the location of lighting, level of shadow formation and contrast, reflectance of the facility, glare, color of light, floor color plan, and material selection is needed. A facility design suitable for domestic users is also needed.

• Korean Journal of Food Science and Technology
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• v.38 no.4
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• pp.475-482
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• 2006

The quality characteristics and functional properties of fermented soybean by lactic acid bacteria (FSB) were investigated and compared with those of soybean (control) and commercial cheonggukjang Powder (CGP). The crude protein, lipid, and fiber contents of FSB were similar to those in CGP. The vitamin $B_2$ content in FSB (1.4 mg%) was similar to the control (1.3 mg%) whereas it was remarkably low in the CGP (0.2 mg%). The bright yellow color of FSB determined by Hunter's colormeter was quite different from the dark reddish brown color of the CGP. The pH of FSB was the lowest and thee amino-nitrogen was 517.2 mg%, which was higher than that in CGP (468.1 mg%). Glutamic acid, aspartic acid and leucine were the most abundant amino acids. In particular, the increase in the glutamic acid level was noticeable in FSB. The fatty acid compositions of FSB and CGP were similar to the control. However, the sucrose and fructose levels were lower after fermentation but the glucose level was higher. The results of isoflavone analysis by HPLC showed that the levels of daidzein and genistein in FSB were as much as 48.33 and 52.82 mg%, respectively, which is higher than that found in CGP. The DPPH free radical scavenging effects of FSB and CGP were 1.8 times higher an those of the control. The fibrinolytic activity determined by the diameter of the lysed area on the fibrin plate was the most effective in FSB. In conclusion, it is believed that FSB has a similar or higher quality than CGP. Therefore, FSB is expected to be good functional food material.

• Microbiology and Biotechnology Letters
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• v.38 no.3
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• pp.283-288
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• 2010

Yam (Dioscorea spp.) has been used as important edible and medicinal natural resource in worldwide and D. alata L. is most popular nourishment among the yam. In this study the composition, color, antioxidation and antimicrobial activity of D. alata Gyeongbuk No. 6 (GB-6), which was established in Gyeongbuk Agricultural Research & Extension Services, Andong, Korea, was compared to those of D. batatas Gyeongbuk No. 1 (GB-1), a major domestic cultivation species. Water content of GB-6 was $78.02{\pm}0.16%$, which is slightly lower than that of GB-1 ($82.6{\pm}0.07%$). The contents of crude protein, crude fat, crude fiber and ash of GB-6 were 0.95, 0.26, 0.85 and 0.70%, whereas those of GB-1 were 1.58, 0.15, 1.39 and 0.88%, respectively. Analysis of color using colormeter showed that the GB-6 is slight dark-yellow than GB-1, and total polyphenol content of GB-6 was 2-fold higher compared than that of GB-1. Sequential organic solvent fractions from methanol extract of GB-6 showed that the ethylacetate fraction has highest total polyphenol ($144.1{\pm}3.20\;mg/g$). Determination of antioxidation activity showed that the ethylacete fraction and water fraction has strong DPPH radical scavenging activity ($IC_{50}=78.32\;{\mu}g/mL$) and reducing power, respectively. In antimicrobial activity assay, the n-hexane and ethylacetate fraction showed antibacterial activity against B. subtilis, L.monocytogenes, S. epidermidis, S. aureus, P. vulgaris, and S. typhimurium. These results provide the possibility of domestic cultivated D. alata GB-6 as a healthy food.