• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.1507-1510
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• 2005

This study was carried out as a part of the research on the development of a maskless and electroless process for fabricating metal micro/nanostructures by using a nanoindenter and an electroless deposition technique. $2-\mu{m}-deep$ indentation tests on Ni and Cu samples were performed. The elastic recovery of the Ni and Cu was 9.30% and 9.53% of the maximum penetration depth, respectively. The hardness and the elastic modulus were 1.56 GPa and 120 GPa for Ni and 1.49 GPa and 100 GPa for Cu. The effect of single-point diamond machining conditions such as the Berkovich tip orientation (0, 45, and $90^{\circ}$) and the normal load (0.1, 0.3, 0.5, 1, 3, and 5 mN), on both the deformation behavior and the morphology of cutting traces (such as width and depth) was investigated by constant-load scratch tests. The tip orientation had a significant influence on the coefficient of friction, which varied from 0.52-0.66 for Ni and from 0.46-0.61 for Cu. The crisscross-pattern sample showed that the tip orientation strongly affects the surface quality of the machined area during scratching. A selective deposition of Cu at the pit-like defect on a p-type Si(111) surface was also investigated. Preferential deposition of the Cu occurred at the surface defect sites of silicon wafers, indicating that those defect sites act as active sites for the deposition reaction. The shape of the Cu-deposited area was almost the same as that of the residual stress field.

• Journal of the Korean Society of Food Science and Nutrition
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• v.33 no.7
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• pp.1230-1236
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• 2004

This study was conducted to investigate the changes in physical properties of the Neungee (Sarcodon aspratus) during dehydration and rehydration. The drying of the sample was completed within 4 hours at 5$0^{\circ}C$ with the air velocity of 1.5 m/s. The reduction in the thickness of the sample were two-fold compared with those in the surface area of the sample. During the drying period, the values of compression distance, break down, deformation rate, distortion, alleviation rate and softness decreased, whereas the values of hardness and alleviation time increased. However, the values of surrender were not changed. The color of the sample during the drying was changed to black with decreased L, a, and b values. The rehydration rate increased rapidly during first 60 min and remained constant after that. The recovery ratio after rehydration of the dried sample was about 30％ and the rheological properties recovered about 44％.

• Korean Journal of Human Ecology
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• v.24 no.1
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• pp.97-109
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• 2015

Recently, because the market for compression wear now includes all consumers, not just professionals, various items for recovery after exercising or for enhanced effects from exercise have been introduced. In this research, a systematic and stepwise design process was proposed to develop compression garment that has both functional area and appropriate pressure to protect the knee when exercising. The U-V format functional area that wraps underneath the knee was selected by considering the shape and change in the skin length when bending the knee. After the selection of the functional area, a total of seven knee design areas, including the existing product, were designed to determine the appropriate pressure. After various movements, the compression garment was ranked in terms of support of the knee, level of pressure, discomfort of seam line, and comfort of popliteal; the preferred design was selected using the quad method. Four compression wear garments were produced using two selected preferred designs; the wear evaluation was performed using a seven-point Likert scale. As a result, the optimal reduction rate of the pattern was calculated based on Ziegert and Keil's method. The applied percentage of the fabric stretch at the upper part of the crotch was 66% for the width and 50% for the length; for the lower part of the crotch, only 66% for the width was applied. Moreover, it was determined that the design of the U-V knee protection part was preferred when a 7 mm square was placed at a 1 mm distance because this not only supports the knee but also allows the fabric to accommodate various skin deformations.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.46 no.4
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• pp.343-350
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• 2013

Instant krill gruel was produced using peeled Antarctic krill Euphausia superba as a high nutritional ingredient and the food quality was investigated. The food quality of krill gruel was examined by measuring proximate composition, cholesterol, calorie, Hunter color value, total amino acids, fatty acids, fluoride, viscoelastic properties, and by sensory evaluation. The krill gruel had a moisture content of 87% and a pH of 6.65. The krill gruel contained 51 kcal/100 g, and 0.1% fat and 3.5 mg/100 g cholesterol. Its fatty acid composition exhibited high levels of unsaturated fatty acids. The levels of oleic acid and linolenic acid were high, and n-3, n-6, and n-9 fatty acid contents ranged from 1% to 6%. The total amino acid content was 2132 mg/100 g, and the levels of glutamic acid, aspartic acid, leucine, alanine, and arginine were particularly high. Essential amino acids accounted for over 30% of the total amino acids. Fluoride level in the krill gruel was 3.07 mg/kg. The viscoelastic properties of the krill gruel were determined as 6.28 Pa at shear stress of 2.51 Pa. In the recovery test, the elastic restoring force after deformation was low.

• Korean Journal of Materials Research
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• v.27 no.11
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• pp.597-602
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• 2017

In this study, an Al-0.7wt%Fe-0.2wt%Mg-0.2wt%Cu-0.02wt%B alloy was designed to fabricate an aluminum alloy for electrical wire having both high strength and high conductivity. The designed Al alloy was processed by casting, extrusion and drawing processes. Especially, the drawing process was done by severe deformation of a rod with an initial diameter of 12 mm into a wire of 2 mm diameter; process was equivalent to an effective strain of 3.58, and the total reduction in area was 97 %. The drawn Al alloy wire was then annealed at various temperatures of 200 to $400^{\circ}C$ for 30 minutes. The mechanical properties, microstructural changes and electrical properties of the annealed specimens were investigated. As the annealing temperature increased, the tensile strength decreased and the elongation increased. Recovery or/and recrystallization occurred as annealing temperature increased, and complete recrystallization occurred at annealing temperatures over $300^{\circ}C$. Electric conductivity increased with increasing temperature up to $250^{\circ}C$, but no significant change was observed above $300^{\circ}C$. It is concluded that, from the viewpoint of the mechanical and electrical properties, the specimen annealed at $350^{\circ}C$ is the most suitable for the wire drawn Al alloy electrical wire.

• Journal of the Korean Society of Food Science and Nutrition
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• v.32 no.3
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• pp.400-405
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• 2003

The surimi processing from jack mackerel and white croaker muscle using acidic and alkaline solubilization was evaluated. The optimum pH for solubilizing protein in acidic and alkaline range was around 2.5 and 10.5, respectively. The optimum pH value for recovery of protein was around 5. The protein solubility was decreased with increase of salt. The homogenized speed and time for maximum solubility were below 9,500 rpm and 30s, respectively The optimum ratio of water to minced muscle was 6 by evaluating breaking force, deformation and whiteness of cooked gel. The protein yield of alkaline processing is higher than that of conventional processing. In addition, the waste water of conventional processing had high solid, nitrogen content and chemical oxygen demand compare to those of acidic and alkaline processing.

• Journal of Dental Rehabilitation and Applied Science
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• v.29 no.3
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• pp.280-289
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• 2013

Removable partial denture for oral function recovery of partial edentulous patients is a complicated treatment because the dentist should consider both hard tissue and soft tissue. Removable partial denture produced without consideration of precise design for each component and rotation of denture may cause fracture, deformation or loss of abutment teeth. In case of failure to achieve a proper denture, the reason of failure should be analyzed and the result must be applied to later RPD cases. Finding the solutions through the failed denture cases will help patients use their dentures more comfortably and keep their sound residual teeth and tissue longer.

• Journal of Fashion Business
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• v.19 no.5
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• pp.1-16
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• 2015

The appearances and geometry structures of knitted fabrics have important effects on their functions as textile fabrics. Structural design of the woven fabric, prior to the manufacturing processes in the weaving mill, often leads to a similar predictable appearance in the final outcome with the corresponding weave design. The increase of the employment of elastic textile yarns in knitting fabrics for comfort stretch or outdoor sports wear knit products has, however, resulted in difficulties in predicting the final appearance of the knit structure design. Due to the stretchability and exceptional recovery behavior of the elastic yarns such as polyurethane elastomeric yarns, the appearance of the final product often differs from the initial knit design. At textile CAD program for preparing tricot knit designs has been employed in this study to predict the two dimensional appearance of the design. The similarities between the designs and corresponding knit products seem to be acceptable for the two-dimensional textile CAD program in this study. However, when elastomeric yarns are partially employed in the polyester filament tricot product, a considerable amount of departure from the design is apparent due to the constriction and/or deformation of property differences in the elastomeric yarns and polyester filament yarns. Therefore, another purpose of this study is to measure the departure of the final tricot product from the initial tricot design, especially in the case employing elastomeric yarns in the knit structure together with regular polyester filament yarns. For measuring the three-dimensional departure, a 3D scanning system has been used for the mesh reconstruction of the fabric specimen. Hopefully, the result from this study will be used as a guide to modify and improve the current textile CAD program proposed for the two-dimensional simulation of the tricot.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.2
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• pp.952-962
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• 2015

In this study, multilayered rings with a large outer diameter have been developed using a hot ring rolling process. The ring rolling process has been analyzed by rigid plastic finite element analyses (FEA) using the AFDEX2D and AFDEX3D/HEXA/RING simulators, where the finite element meshes received severe plastic deformation are remeshed into a fine mesh-size using a dual-mesh system. According to the simulated results, the design variables of the multilayered rings were determined and real tests were conducted to check the validity of the simulation results. By adopting the hot ring rolling process, the input weight of raw materials was reduced by 40% against the conventional hot forging process and that the recovery rate was increased by 24%. The measurement of the averaged roundness was satisfied within 0.5 mm for both the inner and outer diameters. Moreover, the hot ring rolling processes yielded 1.49 Cpk for the outer-diameter and 0.84 Cpk 0.84 for the inner-diameter.

• Journal of the Korean Society for Precision Engineering
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• v.23 no.8 s.185
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• pp.171-177
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• 2006

This study was performed as a part of the research on the development of a maskless and electroless process for fabricating metal micro/nanostructures by using a nanoindenter and an electroless deposition technique. $2-{\mu}m$-deep indentation tests on Ni and Cu samples were performed. The elastic recovery of the Ni and Cu was 9.30% and 9.53% of the maximum penetration depth, respectively. The hardness and the elastic modulus were 1.56 GPa and 120 GPa for Ni and 1.51 GPa and 104 GPa for Cu. The effect of single-point diamond machining conditions such as the Berkovich tip orientation (0, 45, and $90^{\circ}$ ) and the normal load (0.1, 0.3, 0.5, 1, 3, and 5 mN), on both the deformation behavior and the morphology of cutting traces (such as width and depth) was investigated by constant-load scratch tests. The tip orientation had a significant influence on the coefficient of friction, which varied from 0.52-0.66 for Ni and from 0.46- 0.61 for Cu. The crisscross-pattern sample showed that the tip orientation strongly affects the surface quality of the machined are a during scratching. A selective deposition of Cu at the pit-like defect on a p-type Si(111) surface was also investigated. Preferential deposition of the Cu occurred at the surface defect sites of silicon wafers, indicating that those defect sites act as active sites for the deposition reaction. The shape of the Cu-deposited area was almost the same as that of the residual stress field.