• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.591-604
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• 2008

In this study, two design examples of drilled shafts on soft ground in Ho-Chi-Minh City, Vietnam are introduced. One is for a 27-story apartment and the other is for a Arch bridge over Saigon river. Unlikely the normal cases in Korea, all of the bored pile foundations are supposed to be placed on soil layers. Therefore, skin friction between pile and ground is the most crucial design parameter. Three methods using SPT N value of sandy soil -Korean Road Bridge Code(1996), Reese and Wright (1977), and O'Neill and Reese (1988)- were adopted to obtain an ultimate axial bearing capacity. In order to verify the calculated bearing capacity, 3 sets of static load test and a Osterberg Cell test were performed at an apartment site and a bridge site respectively. LRFD (Load Resistance Factored Design) method was compared with ASD (Allowable Stress Design) method. On application of ASD method, safety factor for skin friction was adopted as 2 or 3 while safety factor for end bearing was 3. The design bearing capacities from ASD method matched well with those from LRFD method when safety factor for skin friction was adopted as 2.

• 한국임상수의학회지
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• 제40권2호
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• pp.113-118
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• 2023

Skin and joint diseases are relatively common in dogs. Nutritional complementation is one of the various management strategies for these disorders. This study evaluated the safety and clinical efficacy of Kyungokgo-gamibang in dogs with skin and joint diseases. Thirty dogs with diseases were included and divided into three groups: control group (n = 15), skin group (n = 10), and joint group (n = 5). The skin and joint groups were fed skin and joint gums composed of Kyungokgo-gamibang extract with standard treatment for four weeks. The control group included dogs with skin diseases who were administered standard skin infection treatment for 4 weeks. The physical and laboratory results showed no remarkable adverse effects of Kyungokgo-gamibang extract after its administration in dogs. Clinical efficacy was evaluated using quality of life scale, and levels of cytokines, including interferon-γ, interleukin (IL)-2, IL-6, IL-8, IL-10, monocyte chemoattractant protein-1, and tumor necrosis factor-α, for 4 weeks in all groups. Dermatologic clinical scales were performed for 4 weeks in the control and skin groups. Both the control and skin groups had significantly decreased dermatologic clinical scales, including pruritus and erythema scales (p < 0.05). Among the cytokine levels, only IL-2 concentration was significantly decreased in the skin group after 4 weeks of administration of the Kyungokgo-gamibang extract (p = 0.032). There was no significant difference between the levels of cytokines on days 0 and 28 in the joint group. The quality of life scale was significantly increased after week 4 compared to week 0 in the skin (p = 0.008) and joint groups (p = 0.041). This study suggests that Kyungokgo-gamibang extract can be applied in managing dogs affected by skin and joint diseases without adverse effects.

• 한국환경성돌연변이발암원학회:학술대회논문집
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• 한국환경성돌연변이발암원학회 2002년도 Current Trends in Toxicological Sciences
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• pp.138-138
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• 2002

• Safety and Health at Work
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• 제7권3호
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• pp.208-212
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• 2016

Background: Outdoor workers are at risk of high ultraviolet radiation exposure, and may have difficulty using sun protection. The objectives were to determine the prevalence of sun protection behaviors in a sample of outdoor construction workers, and to assess which factors predict better sun protection practices. Methods: Participants were recruited via construction unions. Workers answered a questionnaire on demographics, skin cancer risk, sun protection behaviors, and job. Sun protection behavior scores (from questions on sunscreen use, sleeved shirt, hat, shade seeking, sunglasses) were calculated by converting Likert-scale answers to scores from 0 to 4, and taking the mean (separately for work and leisure). Determinants of sun protection behavior scores were examined for work and leisure using generalized linear models. Results: Seventy-seven workers had complete questionnaire data (participation 98%). Sun protection behaviors used most often were hats (79% often/always) and sleeved shirts (82% often/always); least prevalent were shade-seeking (8% often/always) and sunscreen (29% often/always). For both work and leisure scores, the strongest predictor was skin type, with fairer-skinned individuals having higher sun protection behavior scores. Workers had higher scores at work than on weekends. Workplaces that required hats and sleeved shirts for safety purposes had higher protection behavior scores. Conclusion: This high-participation rate cohort helps characterize sun protection behaviors among outdoor workers. Workers practiced better sun protection at work than on weekends, suggesting that workplace policies supportive of sun protection could be useful for skin cancer prevention in the construction industry.

• 한국가스학회지
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• 제22권6호
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• pp.1-7
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• 2018

최근 화학공장에서 사고가 빈번히 발생하여 화학공장의 위험성에 대한 논란이 다시 대두되고 있다. 화학공장에서 발생하는 사고유형은 대부분 화재, 폭발, 누출사고이다. 화재, 폭발사고의 경우는 사고발생 직후 사상자가 발생하지만 누출사고는 즉각적으로 대처하지 못해 사상자가 발생하는 경우가 많다. 특히 화학물질이 피부에 침투하는 경우는 즉시 물로 씻어주면 사망, 실명, 화상과 같은 비가역적인 건강장애를 예방할 수 있다. 이렇게 화학물질이 피부, 눈 등에 노출된 경우 씻을 수 있는 장소가 바로 세안 등의 설비(이하 safety shower)이다. 하지만 국내 화학공장은 대부분 1980년대에 건설되어 노후화, 관리미흡 등으로 safety shower가 비상상황 시 정상 작동하지 못하는 경우가 많다. 따라서 설치/관리기준을 통해 safety shower에 대한 성능을 확보하는 것이 필요하다. 이 논문에서는 safety shower의 설치 및 점검기준을 통해 safety shower의 신뢰도를 향상시키는 연구를 수행하였다.

• 한국식품영양과학회지
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• 제39권8호
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• pp.1213-1219
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• 2010

본 연구는 흑마늘을 기능성 화장품 소재로 활용하기 위하여 그 기능성을 in vitro에서 tyrosinase 및 elastase 저해 활성을 측정한 결과 피부노화에 관여하는 두 효소의 활성을 모두 저해하였다. 흑마늘 추출물을 hartley계 기니픽 수컷을 사용하여 피부 1차 자극 실험을 실시한 결과 1차 피부자극지수(P.I.I.)가 0.23으로 practically non-irritation(비자극성)에 해당하는 자극으로 피부 자극이 거의 없었음을 알 수 있었다. Maximization test법으로 피부 감작성을 확인한 결과 시험물질에 의한 홍반과 부종 등이 전혀 유발되지 않았다. 이상의 결과로부터 흑마늘 추출물에 대한 기니픽의 피부 감작율은 0%로, 피부에 대한 피부 감작성이 없는 것으로 확인되었다. 따라서 이러한 본 연구의 결과는 흑마늘 추출물이 기능성 화장품 소재로 피부노화를 억제하는 기능성과 안전성확보된 소재임을 추정할 수 있었다.

• Safety and Health at Work
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• 제6권3호
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• pp.256-262
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• 2015

Background: Heart attack is the most common cause of line-of-duty death in the fire service. Daily aspirin therapy is a preventative measure used to reduce the morbidity of heart attacks but may decrease the ability to dissipate heat by reducing skin blood flow. Methods: In this double-blind, placebo-controlled, crossover study, firefighters were randomized to receive 14 days of therapy (81-mg aspirin or placebo) before performing treadmill exercise in thermal-protective clothing in a hot room [$38.8{\pm}2.1^{\circ}C$, $24.9{\pm}9.1%$ relative humidity (RH)]. Three weeks without therapy was provided before crossing to the other arm. Firefighters completed a baseline skin blood-flow assessment via laser Doppler flowmetry; skin was heated to $44^{\circ}C$ to achieve maximal cutaneous vasodilation. Skin blood flow was measured before and after exercise in a hot room, and at 0 minutes, 10 minutes, 20 minutes, and 30 minutes of recovery under temperature conditions ($25.3{\pm}1.2^{\circ}C$, $40.3{\pm}13.7%\;RH$). Platelet clotting time was assessed before drug administration, and before and after exercise. Results: Fifteen firefighters completed the study. Aspirin increased clotting time before and after exercise compared with placebo (p = 0.003). There were no differences in absolute skin blood flow between groups (p = 0.35). Following exercise, cutaneous vascular conductance (CVC) was $85{\pm}42%$ of maximum in the aspirin and $76{\pm}37%$ in the placebo groups. The percentage of maximal CVC did not differ by treatment before or after recovery. Neither maximal core body temperature nor heart rate responses to exercise differed between trials. Conclusion: There were no differences in skin blood flow during uncompensable heat stress following exercise after aspirin or placebo therapy.

• International Journal of Aerospace System Engineering
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• 제6권1호
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• pp.1-7
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• 2019

In the present study, structural safety and stability on the main wing and tail planes of the 1.2 ton WIG(Wing in Ground Effect) flight vehicle, which will be a high speed maritime transportation system for the next generation, was performed. The carbon-epoxy composite material was used in design of wing structure. The skin-spar with skin-stressed structural type was adopted for improvement of lightness and structural stability. As a design procedure for this study, the design load was estimated with maximum flight load. From static strength analysis results using finite element method of the commercial codes. From the stress analysis results of the main wing, it was confirmed that the upper skin structure between the second rib and the third rib was unstable for the buckling load. Therefore in order to solve this problem, three stiffeners at the buckled region were added. After design modification, even though the weight of the wing was a little bit heavier than the target weight, the structural safety and stability was satisfied for design requirements.

• 농약과학회지
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• 제17권4호
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• pp.478-481
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• 2013

본 연구는 병해충 관리용 유기농업자재 허용물질로 지정된 식물추출물 중 님 추출물(미얀마산, 인도산)과 고삼추출물(중국산)의 독성 평가를 위해 피부자극성과 안점막자극성시험을 수행하였다. 시험결과, 원산지가 다른 님 추출물 2종은 모두 피부자극성과 안점막자극성이 없는 것으로 평가되었고, 고삼 추출물은 피부자극성은 없었고 안점막자극성이 강도로 나타났으나 시간이 경과함에 따라 자극이 경감하는 것으로 평가됐다. 따라서 안점막자극성이 강한 것으로 평가된 고삼 추출물을 유기농업자재로 사용할 때 농작업자에 대한 안전대책이 필요한 것으로 판단된다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 추계학술대회 논문집
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• pp.422-422
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• 2009

This paper describes the structural design of small wind turbine blade by using design of experiments. Blade structure consists of skin, spar and foam. The materials for skin and spar are a kind of Glass/Epoxy and form is polyurethane. It has 7 lay-ups with different ply angle. A factorial design is applied to design the ply angles considering manufacturing constraints and to investigate the safety factor which is calculated by structural analysis. In order to perform the structural analysis, the commercial software ABAQUS is used. Tsai-Wu failure criterion is chosen to compute safety factor. The determination of the significance of effects in the experiments is made through the analysis of variance. The results show that ply angle at skin affects the safety factor of wind turbine blade. And from this result, optimal ply angles of composite blade are achieved.