• Composites Research
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• v.12 no.1
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• pp.28-36
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• 1999

Thermal stress-induced failure in the free edge region of various thin carbon/epoxy composite laminates(1mm thick) has been investigated using the three-dimensional finite-element stress analysis, ultrasonic C-scan and microscopic observations. High thermal in-plane and interlaminar stresses were predicted in the interior layer near the free edge boundaries of the laminates. In the interior lamina, not in the skin lamina, of the thin laminates with lay-up of $[0_2/90_2]_s,\;[45_2/-45_0]_s,\;[0_2/60_2]_s$ treated by liquid $N_2$ immersion, many transverse matrix cracks took place due to thermal stress concentration, which agreed qualitatively with the above predictions.

• Archives of Plastic Surgery
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• v.36 no.4
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• pp.500-502
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• 2009

Purpose: Cutaneous lipomatous neurofibroma is a rare variant of neurofibroma. Histologically, it includes adipose tissue. As far as we aware, only 11 cases of this variant were reported which was predominantly on head, neck and trunk, so we present a case of left pretibial area with literature review. Method: A 17 - year old female who showed a non - tender, protruding $4{\times}4{\times}2cm$ sized mass on the left pretibial area for several months. We totally excised the mass including skin and the subcutaneous fat layer. Results: Pathologic report showed cutaneous lipomatous neurofibroma which was well circumscribed and noncapsulated neoplasm present with focal fatty change. Adipose cells were entrapped in the whirls of spindle cells. There were no lipoblasts or atypical adipocytes. Conclusion: A cutaneous lipomatous neurofibroma on the lower extremity is very rare. In our patient, there were no trauma - related histopathologic changes. Therefore, focal fatty change can be a consequence of metaplasia from multipotential neural cells after migration.

• International Journal of Aeronautical and Space Sciences
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• v.16 no.1
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• pp.8-18
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• 2015

A numerical simulation for a nonslender BWB UCAV configuration with a rounded leading edge and span of 1.0 m was performed to analyze its aerodynamic characteristics. Numerical results were compared with experimental data obtained at a free stream velocity of 50 m/s and at angles of attack from -4 to $26^{\circ}$. The Reynolds number, based on the mean chord length, is $1.25{\times}106$. 3D multi-block hexahedral grids are used to guarantee good grid quality and to efficiently resolve the boundary layer. Menter's shear stress transport model and two transition models (${\gamma}-Re_{\theta}$ model and ${\gamma}$ model) were used to assess the effect of the laminar/turbulent transition on the flow characteristics. Aerodynamic coefficients, such as drag, lift, and the pitching moment, were compared with experimental data. Drag and lift coefficients of the UCAV were predicted well while the pitching moment coefficient was underpredicted at high angles of attack and influenced strongly by the selected turbulent models. After assessing the pressure distribution, skin friction lines and velocity field around UCAV configuration, it was found that the transition effect should be considered in the prediction of aerodynamic characteristics of vortical flow fields.

• Environmental Analysis Health and Toxicology
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• v.21 no.1 s.52
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• pp.35-43
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• 2006

Reproduction and organ structure of the pale chub, Zacco platypus in Isa stream were investigated by means of histological methods. The results of the study confirmed reproductive abnormality and histopathological features in the pale chub. The gonadosomatic index (GSI) of the fish showed two peak in April and August. In summer season, GSI of the male was about two times of the female's GSI. Monthly variation of the gonadal development was very irregular. From the histological analysis of the organ structure, epidermal atrophy, necrosis and hyperplasia of pigment cell were observed in the skin. Epithelial layer lifting and clubbing of the lamella and bifurcation of the filament were observed in the gill. Also histological changes as congestion, cytoplasmic degeneration of hepatic cell, degeneration of bile duct, glomerular dilatation, degeneration of renal tubule and pycnosis of interstitial cell were identified in the liver and kidney, respectively.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.16 no.6
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• pp.95-100
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• 2017

Recently, biomedical-grade texture material gauze has often been used to treat wounds. At this time, it is difficult to remove scratches and pushed gauze; if you remove it with force, the tissue may separate and bleeding may occur again. In this study, we studied a method to apply medical-grade silicone material. Similar to the research result that hypertrophic wounds reduce the thickness of scar marks. Through mini-pig experiments, we evaluated the effects on scar treatment. The test results showed that the silicone cover layer applied to the wound site had a sealing effect on the wound area, skin temperature, and histopathological examination. In conclusion, gel treatment utilizing a biocompatible substance had the effect of minimizing hypertrophic scars.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.21 no.2
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• pp.49-56
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• 1995

Chitosan microcapsules and microbeads were prepared by W/O emulsion method, and their morphologies were observed through SEM. The microcapsules have skin layer of 8 Um and 250 Um of mean diameter, The swelling test showed higher s welling ability in protic solvents than in aphotic solvents. After containing moth-yl violet in the microcapsules, the release patterns were investigated. The results sho wed that the addition of Iysozyme in pH 5.1 acetate buffer accelerated the re-lease rate. In case of the microbeads, the mean diameter was about 70 Um. The surface of the microbeads showed porous structures. The swelling ability of the beads revealed two times higher than the one of the microcapsules.

• Journal of the Society of Naval Architects of Korea
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• v.55 no.3
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• pp.265-273
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• 2018

Direct numerical and large eddy simulations of transitional flows around studs installed on flat plate and bulbous bow have been performed to investigate an effectiveness of turbulence stimulators on laminar-to-turbulence transition at a very low speed. The flow velocity was determined to be 0.366m/s corresponding to 4 knots of full-scale ship speed when the objective ship was Kriso container ship. The spatial evolution of skin friction coefficient disclosed that a fully development of turbulence was observed behind the second stud installed on flat plate while a rapid transition from laminar to turbulence gave rise to the fully development of turbulence behind the first stud installed on bulbous bow. A comparison of streamwise mean velocity profiles showed that the viscous sublayer and log-layer were in good agreement with previous results although the friction velocity of Smagrosinsky sub-grid scale model was about 10% larger than that of direct numerical simulation. While the turbulence intensities of bulbous bow was similar to those of flat plate in inner region, larger intensities of turbulence were observed in outer region of bulbous bow than those of flat plate.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.4
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• pp.733-738
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• 2020

In the recent years, the development of coastal zone has been advancing, and the chance of leisure activity has increased near the sea. However, the destruction of ozone layer has resulted in an increase in the amount of ultraviolet radiation reaching the earth surface. The human body is harmfully influenced as skin cancer and eye damage by ultraviolet radiation. Especially, the effect of ultraviolet radiation on beach is higher than that inland area due to the reflection from the sand. This study is expected to use basic data on the method of measuring ultraviolet reflections on east coast beaches using remote sensing.

• Archives of Craniofacial Surgery
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• v.19 no.3
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• pp.222-226
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• 2018

A 70-year-old male with a history of diabetes mellitus, hypertension, and coronary stent insertion visited our hospital 7 days after biting his lower lip. Swelling and inflammation had worsened despite debridement and antibiotic treatment. On the 8th hospital day, fungal infection with Candida albicans and superimposed bacterial infection with Klebsiella pneumoniae were found on tissue culture. Extensive necrosis resulted in a defect of approximately 3/4 of the entire lower lip and a full-layer skin defect from the vermilion to the gingivobuccal sulcus at the right corner of the mouth. To correct drooling, incomplete lip sealing, and trismus, staged reconstruction was performed with consideration of cosmetic and functional features. The treatment process using staged reconstruction and antifungal treatment for an extensive lower lip defect caused by fungal stomatitis is described.

• Membrane and Water Treatment
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• v.5 no.3
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• pp.171-182
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• 2014

Organic compounds are adsorbed on RO/NF membranes, and the adsorption may influence the rejection of organic compounds by the membranes. Because almost RO/NF membranes are composite membranes, the results obtained by adsorption experiment with using membrane pieces are unable to avoid the influence by the support membrane. In this work, the interaction between membrane polymer and organic solutes was examined by an inverse HPLC methodology. Poly (m-phenylenetrimesoylate), the constituent of skin layer of RO/NF membranes, was coated on silica gel particles and used as a stationary phase for HPLC. When water was used as a mobile phase, almost hydrophilic aliphatic compounds were not effectively adsorbed on the stationary phase, although hydrophobic compounds were slightly adsorbed. The results indicated that the hydrophilic aliphatic compounds are useful probe solutes to examine the molecular sieving effect of a membrane. When water was used as a mobile phase, the aromatic compounds were strongly retained, and therefore $CH_3CN/H_2O$ (30/70) was used as a mobile phase. It was revealed that the adsorption of aromatic compounds was controlled by stacking between solute and polymer and was hindered by non-planar structure and substituents.