• Nuclear Engineering and Technology
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• 제52권10호
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• pp.2370-2378
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• 2020

Building materials contribute significantly to the indoor radon and thoron levels. Therefore, parameters that influence the exhalation rates of radon and thoron from building material need to be analyzed closely. As a preliminary study, the effects of humidity on exhalation rates were measured using a system with an accumulation chamber and RAD7 detector for Korean brick, Korean soil, and Indonesian brick. Resulting doses to a person who resides in a room constructed from the building materials were assessed by UNSCEAR method for different air exchange rates. The measurements have revealed that Korean brick exhaled the highest radon and thoron while Indonesian brick exhaled the lowest thoron. Results showed that for a typical low dense material, radon and thoron exhalation rate will increase until reached its maximum at a certain value of humidity and will remain saturated above it. Analysis on concentration and effective dose showed that radon is strongly affected by air exchange rate (ACH). This is showed by about 66 times decrease of radon dose from 0.00 h^-1 to those of 0.50 h^-1 ACH and decrease by a factor of 2 from 0.50 h^-1 to those of 0.80 h^-1. In case of thoron, the ACH doesn't have significant effects on effective dose.

• 한국진공학회지
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• 제7권4호
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• pp.374-380
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• 1998

글로벌 모델을 사용하여 $CF_4$ 플라즈마 내부에서의 각 중성 및 이온 라디칼 밀도를 계산하였다. 중성 입자로서는 플루오린 원자가 가장 많고, 높은 입력 전력 조건의 경우 CF 나 $CF^+$와 같은 저 분자 해리종이 주종을 이룬다. 압력이 증가 할수록 하전 입자의 밀도는 증가하나 전자 온도의 감소로 이온화율은 감소한다. 공급 가스인 $CF_4$의 해리율은 압력에 따 라 증가한후 다시 감소하는 양상을 보인다. 전자 온도 및 밀도는 입력유량에 대해서 거의 변화가 없다. $CF_4$의 해리율은 유량 증가에 따라 선형적으로 감소하며 이는 $CF_3$의 증가와 CF의 감소로 이어진다. 식각 실험 결과와의 비교를 통해 플루오로 카본 이온종 및 높은 C/F비를 갖는 중성 라디칼의 상대적 밀도 증가가 $SiO_2$/Si식각 선택도 향상에 주요함을 알 수 있다.

• Archives of Plastic Surgery
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• 제45권1호
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• pp.58-61
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• 2018

Background Venous anastomosis is an important component of digital replantation, but is not always feasible, as some cases require external bleeding to treat venous congestion in the replanted tissue. In the present study, we evaluated the relationship between the number of vein anastomoses and the survival rate of Tamai zone I replantations. Methods A retrospective review was performed of all patients who underwent replantation of a fingertip amputation between 2014 and 2016. Patient charts were reviewed for demographic information, the mechanism of injury, the number of venous anastomoses, and the use of anticoagulation, external bleeding, and/or leeches. The cohort was divided into 3 groups depending on the number of venous anastomoses: no veins (group 1), a single vein (group 2), and 2 or more veins (group 3). Survival rates and external bleeding rates were analyzed across the groups. Results The review identified 143 fingertip replantations among 134 patients. The overall survival rate was 94% (135 of 143). Failures were due equally to venous complications (n=4, 50%) and to arterial complications (n=4, 50%). Our analysis did not identify any correlation between the number of veins anastomosed and the replant survival rate (P=0.689). However, a greater number of anastomoses was associated with a significantly lower frequency of external bleeding (P=0.017). Conclusions The number of venous anastomoses was not correlated with the survival rate. However, a greater number of venous anastomoses was associated with a decreased need for external bleeding, corresponding to a significant decrease in the need for postoperative monitoring and leech therapy.

• 동의생리병리학회지
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• 제17권4호
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• pp.1031-1036
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• 2003

To certify the protective effect of herbal medicine against oxygen free radical-induced myocardiotoxicity, cytotoxicity was measured using TBARS assay and Beating rate in the presence of Tongryeong-san(TRS) extracts or single constituents of this prescription. Myocardial toxicity was evaluated in neonatal rat myocardiocytes in cultures. In the present study, xanthine oxidase/hypoxanthine (XO/HX) resulted in a increase in lipid peroxidation and decreases in beating rate in cultured myocardial cells. In the effect of TRS extract, it showed the prevention from the XO/HX-induced cardiotoxicity by the increases of beating rate as well as the decrease of lipid peroxidation, In the protective effect of Faeces Trogopterori(FT), Pollen Typhae(PT), Caulis Akebiae(CA) and Radix Paeoniae Rubra(PRR), all the extracts were significantly effective in the protection of XO/HX-induced cardiotoxocity in cultured myocardial cells by the increase of beating rate as well as th decrease of lipid peroxidation. From these results, they show that XO/HX is cardiotoxic in cultured myocardial cells derived from neonatal rat, and it suggests that TRS, FT, PT, CA and PRR extracts are positively effective in the blocking in XO/HX-induced cardiotoxicity.

• 한국엔터테인먼트산업학회논문지
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• 제14권8호
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• pp.197-202
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• 2020

본 연구에서는 20대 여성의 카페인 중독이 심장호흡기계 능력에 미치는 영향을 조사하였다. 본 연구의 대상자는 G 광역시 소재의 H 대학교 여학생 35명을 카페인 중독자(n=17)과 카페인 비중독자(n=18)가 참여하였다. 심장능력을 평가하기 위해 사이클 에르고미터를 사용하여 최대산소섭취량, 최대에너지소비량, METs를 측정하였으며, 호흡기계 능력은 파워브리드 K5를 사용하여 최대들숨압, 평균들숨압, 최대들숨유속, 평균들숨유속, 최대들숨량, 평균들숨량을 측정하였다. 본 연구의 결과는 심장능력에서 카페인 중독군은 카페인 비중독군에 비해 최대산소섭취량과 METs에서 통계학적으로 유의한 감소를 보였으며, 호흡기계 능력에서는 카페인 중독군이 비중독군에 비해 최대들숨압, 평균들숨압, 최대들숨유속, 평균들숨유속에서 통계학적으로 유의한 감소를 보였다. 본 연구의 결과를 종합하면, 카페인 중독은 20대 여성의 심장호흡기계 능력의 감소를 보였다. 따라서 본 연구의 결과는 20대 여성의 카페인 중독예방을 위한 기초자료로 활용할 수 있을 것이다.

• 대한토목학회논문집
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• 제28권2D호
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• pp.191-203
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• 2008

사업용 자동차 교통사고 특성 분석(도로교통안전관리공단, 2007)에 따르면, 사업용 차량의 1만대 당 교통사고 발생률과 사망률이 비사업용 차량에 비해 각각 6.7배와 5.3배 높은 것으로 나타났다. 또한 최근 10년 동안 전체 교통사고는 연평균 1.5% 감소한데 비하여, 사업용 차량의 교통사고는 연평균 2.0%씩 증가하는 추세를 보이고 있다. 최근 10년 동안 사업용 차량 중 버스와 화물트럭의 교통사고 발생건수는 꾸준히 감소하였다. 그러나 택시의 교통사고 발생건수만은 연평균 5.6%씩 꾸준히 증가하고 있다. 이와 같은 상황에서 심리성격 분석 기법인 Q분석을 통하여, 택시 운전자의 운전 성향별 특성을 파악하고, 운전 성향별 교통사고 저감대책을 마련하고자 하였다.

• Journal of Veterinary Science
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• 제24권6호
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• pp.81.1-81.12
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• 2023

Background: The incidence of colic and the outcomes of colic surgery have not been surveyed in racetracks in Korea. Objectives: This study examined the incidence, mortality, and case fatality of colic and investigated the effects of age and sex after an exploratory celiotomy on the long-term survival rate (return to racing), subsequent racing performance, and career longevity. Methods: The incidence, mortality, and case fatalities of colic were examined over an 11-year period. The records of 40 horses that had undergone a celiotomy, after participating in at least one race and 75 race-matched control horses were analyzed. The racing performance and career length of the horses that returned to racing post-surgery were compared with a control group. Results: The annual incidence, fatality rate of colic, and annual mortality rate at Seoul Racecourse were 6.5, 2.8 per 100 horse-years, and 0.2 deaths cases per 100 horse-years, respectively. Of the 40 horses that underwent colic surgery, 26 (65%) returned to racing. The likelihood of returning to racing decreased with increasing age of the horses, and geldings had a lower probability of returning. While the performance in the five preoperative races between the two groups was not significantly different, a significant decrease in racing performance was observed after the surgery date (p < 0.01). Horses that underwent colic surgery did not show a significant decrease in career length. Conclusions: Surgical treatment for colic at the age of three and four years had a negative impact on the racing performance. On the other hand, there was no significant difference in career longevity between the two groups.

• Tuberculosis and Respiratory Diseases
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• 제79권2호
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• pp.58-69
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• 2016

Lung cancer causes the most cancer deaths in Korea. Although the smoking rate has begun to decrease, the prevalence of lung cancer is still increasing. We reviewed the national lung cancer registry data and the data published about lung cancer in Korea. In 2012, the crude incidence rate of lung cancer was 43.9 per 100,000. The age-standardized mortality rate of lung cancer was 19.8 per 100,000. The 5-year relative survival rate for lung cancer was 11.3% from 1993 to 1995 and increased to 21.9% in the period from 2008 to 2012. Lung cancer occurring in never-smokers was estimated to increase in Korea. Adenocarcinoma is steadily increasing in both women and men and has replaced squamous cell carcinoma as the most common type of lung cancer in Korea. In patients with adenocarcinoma, the frequency of EGFR mutations was 43% (range, 20%-56%), while that of the EMK4-ALK gene was less than 5%.

• 산업기술연구
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• 제17권
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• pp.169-174
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• 1997

This investigation was carried out to study on the generation property, management and seperate collection rate of solid waste in the Gu-Gok Falls. Generation rate of solid waste was 80.785kg/day and unit waste generation rates was $65.55g/day{\cdot}tourist$ one person. Physical component of solid waste were garbage 46%, papers 20%, empty bottles 10%, respectively. A plan is required to decrease generation rate of garbage waste. As result to investigate separated garbage can, papers and can were separated more than 60%. But empty bottles and scrap iron were separated less than 50%. P.E.T, steel can, aluminum can and empty bottles were 20% of total generation rate, and profit of reuse is \700,800/year.

• 대한치과의사협회지
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• 제12권2호
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• pp.113-118
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• 1974

The importance of light and stress as factors in growth has not previously been clearly delineated. As the result of using experimental environments on growth rate of incisors in 24 young rats with body weight ranging 58 Gm to 62 Gm., the author obtained following conclusions. 1) The eruption rate of normal rats incisors was 0.421mm in upper incisors and 0.592mm in lower incisors per a day respectively. 2) In light environment, growth rate of incisors in rats and body weights were found to increase more rapidly during the 8-week experimental period in comparison with any environments. 3) In stress environment, growth rate of incisors in rats and body weight were found to decrease in comparison with amy environments during the 8-week experimental period.