• Journal of the Korean Geotechnical Society
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• v.22 no.8
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• pp.25-31
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• 2006

Over the years the investigation of behaviour of piles in groups connected to a cap in consolidating soil has attracted far less attention than the study of isolated piles in groups. In this paper, a series of three-dimensional numerical simulations have been performed to study the behaviour of pile groups connected to a cap in consolidating ground. Both elastic no-slip and elasto-plastic slip analyses were considered. Based on the analysis results, when piles were connected to a cap, tensile forces were developed near the pile head at the outer piles. Elastic solution and no-slip analysis over-predicted the tensile force near the pile head for outer piles. Relatively speaking, the number of piles in a group is more important than the pile spacing in terms of the influence of negative skin friction on the pile behaviour. The issue on the development of tensile forces on the pile head at the outer piles is perhaps needed to be carefully considered in the pile design to prevent the damages of the pile-cap connection.

• Fire Science and Engineering
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• v.23 no.5
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• pp.110-116
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• 2009

This study is related with fire risk assessment for fire and smoke spread of double skin facade system by use of FDS (Fire Dynamics Simulator) which is a computational fluid dynamics (CFD) model of fire-driven fluid flow. For the study, fire scenario is intended to evaluate the impact of a fire spread for glazed office building. The major purpose of this study is to analyze the fire risk depending on the width of between inner skin and outer skin and to present fire prevention method regarding double skin facade system. The result of analysis presents fire spread more vertically as intermediate space becomes narrow. It is anticipated that fire can spread upper 2 stories above the fire floor if intermediate space with not more than 1m width. Therefore, prevention of vertical fire spread is required.

• KSBB Journal
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• v.21 no.5
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• pp.394-400
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• 2006

When the papain, which is a sort of Cystein protease, is applied to the outer skin, it decomposes the protein which forms the peeled outer skin and speeds up metabolism. Therefore, it is one of the most important cosmetics compositic which keeps the function of skin normal. When the papain is used in cosmetics with surfactant, the activity of papain is reduced rapidly. In this study, the modified papain with extreme stability negative ionic environment was developed by directed evolution

• Journal of Fashion Business
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• v.11 no.6
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• pp.35-51
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• 2007

This research was administered in order to know the effects of heels on the foot by comparing the foot environmental characteristics when common shoes and elevated shoes are worn. First, 157 male adults in their 20s through 40s living in Busan were the inquiry subjects to reveal the shoes-wearing reality of adult males. Second, 7 male adults in their early 20s became the subjects for the experiments of wearing common shoes and elevated shoes. 1. Inquiry Results of Shoes-Wearing Reality Common-shoes wearers were in the order: 20s (43.9%) > 30s (24.8%) > 40s (8.3%). Elevated-shoes wearers were mostly 20s (12.1%), followed by 30s (8.3%) and 40s (2.5%). Among the wearing effects of elevated shoes were 'looking taller' (66.7%), 'no height complex & more confidence' (30.6%), and 'higher work efficiency' (2.8%). In sum, 97.3% of the male subjects believed in great positive effects by wearing elevated shoes. 2. Shoes-Wearing Experiment Results In foot skin temperature, significant differences between the two groups were admitted in outer foot a (p<0.05) and other areas (p<0.001), except in the instep. Elevated-shoes group had bigger skin temperature, while the order of temperature was the instep, the big toe, inner foot a/b/c and outer foot a/b/c. Significant difference was accepted in total sweat rate (p<0.05) and local sweat rate (p<0.01). Elevated-shoes group appeared higher in both rates. Significant difference (p<0.001) between the two groups was recognized in fatigue degrees after wearing, whereas significance (p<0.05) in elevated-shoes group was approved in fatigue before and after exercise. So elevated-shoes group experienced more fatigue, especially after exercise.

• Biomedical Science Letters
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• v.16 no.4
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• pp.349-357
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• 2010

We have examined the histological changes of skin during hair follicle growth after depilation in C57BL/6N mice. We first studied on histological changes of number of mast cells and thickness of skin during hair follicle growth periods (telogen, 1 day, 3 day, 5 day, 10 day, 14 day, 17 day and 21 day after depilation) by toluidine blue, Giemsa and H&E staining methods. We second studied immunoreactive density of cytokines and Brdu labeled cells in skin during hair follicle growth periods after depilation in C57BL/6N mice by immunohistochemical methods. The histological changes on skin thickness was increased from telogen to 14 day. The number of mast cells was decreased in 3,5 and 10 day and increased in 14, 17 and 20 day after depilation. Immunoreactive density of cytokines [protein kinase C-${\alpha}$ (PKC-${\alpha}$), c-kit, and vascular endothelial growth factor (VEGF)] in 1, 3, 5, 10, and 14 day after depilation was mildly stained in bulge and cutaneous trunci m., but immunoreactive density of cytokines in 17 and 21 day was heavily stained in epidermis, bulge, outer root sheath (ORS), inner root sheath (IRS) and cutaneous trunci m.. Immunoreactive density of Brdu labeled cells in skin in 1 and 3 day was heavily stained in bulge, epidermis and connective tissue under the cutaneous trunci m.. In all periods, immunoreactive density of Brdu labeled cells in skin was heavily stained in bulge, subcutaneous tissue, cutaneous trunci m, ORS and IRS. These experiments suggest that histological changes related to hair follicle growth elevated mast cell counts, skin thickness and epidermis thickness and heavily stained immunoreactive density of cytokines and Brdu labeled cutaneous trunci m. and connective tissue under the cutaneous trunci m. after depilation in C57BL/6N mice.

• Archives of Craniofacial Surgery
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• v.18 no.2
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• pp.141-144
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• 2017

An odontogenic cutaneous fistula is a pathological communication between the outer skin surface of the face and the oral cavity. Facial cutaneous fistula is a complication of odontogenic infection that is often misdiagnosed with skin infection. We report a rare case, which was diagnosed as basal cell carcinoma based on the biopsy of skin lesions in the patient who had been diagnosed with odontogenic cutaneous fistula. A 64-year-old male patient presented with a cutaneous odontogenic fistula. The patient had undergone surgical extraction of fistula tract and loose tooth before dermatology or plastic surgery consultation. With the biopsy and computed tomography, it was confirmed that fistula and basal cell carcinoma. However, the connection between the fistula and skin cancer was not clear. Positron emission tomography-computed tomography scan was performed and was not detected as other local or distant metastasis. After that, wide excision of the skin lesion was performed. Although skin cancer is not commonly observed, it is necessary to rule out this disease entity by performing biopsy of skin lesions.

• Journal of the Korean Society of Fashion and Beauty
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• v.3 no.2 s.2
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• pp.12-17
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• 2005

Efficiency study of chamomile and Thyme essential oil about the basal layer & sebaceous gland in dry-skin induced by surfactant is as following : 1. Formal observation of outer skin layer and basal layer There was refreshing effects about Surfactant induction skin inflammation in Chamomile, Thyme essential oil processing group but effect in surface layer appeared by higher thing in Chamomile essential oil and it could know that thing which do not use Thyme essential oil in case Thyme essential oil is ultraviolet rays allergy at skin care because Melanocyte appear on the surface is bigger than Chamomile essential oil that it was usefully reaction in basal layer. 2. Formal observation result of sebaceous glands. There are few damages in all group but there is recuperative through excessive water damage by excessive a sebaceous gland made of mulberry bark secretion because Thyme essential oil application group cause chapped skin phenomenon after surface-active agent processing but is seen that difference does not exist greatly and Thyme essential oil that general skin is strong in permeation is effective, but Surfactant induction skin inflammation estimates that Chamomile essential oil is effective. Therefore, it was considered that use of Chamomile essential oil is effectiveness than Thyme essential oil by essential oil used for recovery after damage of inflammation etc..

• International Journal of High-Rise Buildings
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• v.12 no.2
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• pp.129-136
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• 2023

Natural ventilation has proven to be an effective passive strategy in improving energy efficiency and providing healthy environments. However, such a strategy has not been commonly adopted to tall office buildings that traditionally rely on single-skin façades (SSFs), due to the high wind pressure that creates excessive air velocities and occupant discomfort at upper floors. Double-skin façades (DSFs) can provide an opportunity to facilitate natural ventilation in tall office buildings, as the fundamental components such as the additional skin and openings create a buffer to regulate the direct impact of wind pressure and the airflow around the buildings. This study investigates the impact of modified multi-story type DSFs on indoor airflow in a 60-story, 780-foot (238 m) naturally ventilated tall office building under isothermal conditions. Thus, the performance of wind effect related components was assessed based on the criteria (e.g., air velocity and airflow distribution), particularly with respect to opening size. Computational fluid dynamics (CFD) was utilized to simulate outdoor airflow around the tall office building, and indoor airflow at multiple heights in case of various DSF opening configurations. The simulation results indicate that the outer skin opening is the more influential parameter than the inner skin opening on the indoor airflow behavior. On the other hand, the variations of inner skin opening size help improve the indoor airflow with respect to the desired air velocity and airflow distribution. Despite some vortexes observed in the indoor spaces, cross ventilation can occur as positive pressure on the windward side and negative pressure on the other sides generate productive pressure differential. The results also demonstrate that DSFs with smaller openings suitably reduce not only the impact of wind pressure, but also the concentration of high air velocity near the windows on the windward side, compared to SSFs. Further insight on indoor airflow behaviors depending on DSF opening configurations leads to a better understanding of the DSF design strategies for effective natural ventilation in tall office buildings.

• Journal of Mechanical Science and Technology
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• v.17 no.4
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• pp.562-570
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• 2003

This experimental study concerns the characteristics of vortex flow in a concentric annulus with a diameter ratio of 0.52, whose outer cylinder is stationary and inner one is rotating. Pressure losses and skin friction coefficients have been measured for fully developed flows of water and of 0.4% aqueous solution of sodium carboxymethyl cellulose (CMC), respectively, when the inner cylinder rotates at the speed of 0～600 rpm. Also, the visualization of vortex flows has been performed to observe the unstable waves. The results of present study reveal the relation of the bulk flow Reynolds number Re and Rossby number Ro with respect to the skin friction coefficients. In somehow, they show the existence of flow instability mechanism. The effect of rotation on the skin friction coefficient is significantly dependent on the flow regime. The change of skin friction coefficient corresponding to the variation of rotating speed is large for the laminar flow regime, whereas it becomes smaller as Re increases for the transitional flow regime and. then, it gradually approach to zero for the turbulent flow regime. Consequently, the critical (bulk flow) Reynolds number Re$\_$c/ decreases as the rotational speed increases. Thus, the rotation of the inner cylinder promotes the onset of transition due to the excitation of Taylor vortices.

• Journal of Energy Engineering
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• v.11 no.4
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• pp.299-305
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• 2002

The present experimental and numerical investigations are performed on the characteristics of transitional flow in a concentric annulus with a diameter ratio of 0.52, whose outer cylinder is stationary and inner one rotating. The pressure losses and skin-friction coefficients have been measured for the fully devel-oped flow of water and that of 0.2％ CMC-water solution at a inner cylinder rotational speed of 0∼600 rpm, respectively. The transitional flow has been examined by the measurement of pressure losses to reveal the relation of the Reynolds and Rossby numbers with the skin-friction coefficients. The occurrence of transition has been checked by the gradient changes of pressure losses and skin-friction coefficients with respect to the Reynolds numbers. The increasing rate of skin-friction coefficient due to the rotation is uniform for laminar flow regime, whereas it is suddenly reduced for transitional flow regime and, then, it is gradually decreased for turbulent flow regime.