• 한국지반공학회논문집
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• 제22권8호
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• pp.25-31
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• 2006

압밀이 진행 중인 지반에 근입된 기초판으로 연결된 말뚝의 거동과 관련된 연구는 기초판으로 연결되지 않은 군말뚝의 거동에 관한 연구에 비하여 매우 부족한 실정이다. 본 논문에서는 일련의 3차원 수치해석을 통해서 압밀이 진행중인 지반에 근입된 군말뚝의 거동에 대한 연구를 수행하였다. 말뚝-지반 경계면에서의 항복(slip)을 고려하지 않은 탄성해석 및 slip을 고려한 탄-소성 해석을 실시하였다. 본 연구 결과, 기초판과 연결된 말뚝의 경우 인장력이 외곽부 말뚝 두부부근에서 발생하는 것으로 나타났고, 탄성이론에 의한 해석 및 slip을 고려하지 않은 해석은 이러한 인장력을 과대평가하는 것으로 해석되었다. 또한 외곽부 말뚝의 인장력 발생은 말뚝의 간격보다는 군말뚝 내의 말뚝개수에 더 큰 영향을 받는 것으로 나타났다. 향후 부마찰의 영향을 받는 말뚝의 설계시 말뚝-기초판 결합부의 파손을 방지하기 위해, 외곽부 말뚝에 작용하는 인장력을 고려해야 할 것으로 분석되었다.

• 한국화재소방학회논문지
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• 제23권5호
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• pp.110-116
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• 2009

본 연구는 Double Skin System의 화재 전파 위험성을 전산유체역학모델인 FDS를 이용하여 평가하였다. 화재모델링을 구현하기 위해 오피스 용도의 단위 구획공간을 화재지역으로 선정하였으며, 화재시나리오는 외창으로의 연소확대 위험 분석을 위하여 일반적으로 많이 설치되는 시스템조건들을 Case로 선정하여 분석하였다. 본 연구의 목적은 일반적으로 많이 사용되는 Double Skin System의 설치 간격에 따른 건물상층부로의 화재확대 위험성을 평가하고, 이에 따른 방화대책 등을 수립하는데 있다. 해석 결과, 더블스킨 중간층 간격이 넓을수록 상부층으로 연소확대 영향이 작은 것을 확인할 수 있었으며, 중간층 간격이 1m 미만인 경우는 발화층 상부 2개층으로 연소확대가 예상되므로 층간연소 확대 방지 시스템이 요구됨을 알 수 있다.

• KSBB Journal
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• 제21권5호
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• pp.394-400
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• 2006

이 연구의 최종 목표는 방향성 분자진화기술(directed molecular evolution)을 이용한 음이온에 안정한 papain의 개발이다. 음이온 안정성 papain 생산을 위한 유전자의 방향성 분자진화 방법 개발이 이루어졌으며 분자진화된 음이온 안정성 papain의 스크리닝 방법 개발됐다. 분자진화된 papain의 아미노산 서열 및 특성 분석과 분자진화된 재조합 papain의 생산방법 확립되었다. 분자진화된 재조합 papain의 formulation 및 제품 적용화 기술 개발이다. 연구 결과 Papain petidase IV 유전자의 확보 및 발현 균주 개발하였고 음이온 안정성 papain 유전자를 얻기 위한 분자진화의 방법 개발 및 조건 확립하였다. 분자진화 방법으로 error prone PCR 방법 확립, DNA shuffling을 통한 mutagenesis 방법 확립, staggered extension process 방법 확립 및 분자 진화된 음이온성 안정성 papain의 효율적 스크리닝 방법 개발하였다. Skim milk agar plate 이용, 활성 및 안정성이 뛰어난 개량형 papain을 Filter paper방법을 이용하여 screening 방법을 개발하였다.

• 패션비즈니스
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• 제11권6호
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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.

• 대한의생명과학회지
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• 제16권4호
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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.

• 대한두개안면성형외과학회지
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• 제18권2호
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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.

• 한국패션뷰티학회지
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• 제3권2호
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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..

• 국제초고층학회논문집
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• 제12권2호
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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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• 제17권4호
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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.

• 에너지공학
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• 제11권4호
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• pp.299-305
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• 2002

본 연구에서 실험과 수치해석 검증은 지름비 0.52인 동심환형관내에서 안쪽축이 회전하고 바깥쪽축이 고정된 유동장의 유동특성을 수행하였다. 압력손실과 마찰계수는 안쪽축이 0~600 rpm 회전시 물과 0.2% CMC 수용액을 완전히 발달된 유동장에서 측정하였다. 천이유동은 표면마찰계수(C$_{f}$ )에 대하여 로스비수(Ro)와 레이놀즈수(Re)관계를 나타내기 위하여 압력손실 측정에 의해 확인하였다. 천이발생은 레이놀즈수에 대하여 압력손실과 마찰계수의 구배변화에 의해 조사하였다. 회전으로 인한 마찰계수의 증가율은 천이영역에서 대하여 갑자기 감소함에 반하여 층류영역에서 균일하며, 난류영역에서는 점차적으로 감소함을 알 수 있었다.