• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 춘계학술발표회논문집(2)
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• pp.745-752
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• 1995

고연소도 액체금속로용 금속연료를 개발하고자 U-l0wt%Zr 합금중 Zr 원소 대신에 X(:Si, Ta, Nb, W, Mo) 원소를 첨가한 U-7wt%Zr-3wt%X(:Si, Ta, Nb, W, Mo) 합금을 제조하여 미세조직에 미치는 합금원소 첨가의 영향을 조사하였다. 그 결과 U-7 wt%Zr-3wt%Si 합금을 제외한 모든 U-7wt%Zr-3wt%X(:Ta, Nb, W, Mo) 합금은 Matrix에 있어서 Laminar Structure를 그대로 유지하였다. U-7wt%Zr-3wt%Si 함금을 제외한 모든 U-7wt%Zr-3wt%X(:Ta, Nb, W, Mo) 합금의 주요한 상은 U-l0wt% Zr 합금과 마찬가지로 $\alpha$-U 및 $\delta$-UZr$_2$ 상이었다. U-7wt%Zr-3wt%X(:Ta, Nb, W, Mo) 합금은 U-l0wt%Zr 합금에 비해 Lamina Thickness가 크게 감소되었다. 특히 U-7wt%Zr-3wt%Mo 합금의 경우에 있어서는 U-l0wt%Zr 합금에 비해 1/3배 정도까지 Lamina Thickness가 크게 감소하였다. 이와 같은 합금원소 첨가에 의한 Laminar Structure의 미세화는 액체금속로강 금속연료내 Fission Gas의 Inter-connected Path가 보다 더 잘 형성됨으로 인해 Fission Gas Bubble에 대한 방출속도를 크게 증가시켜서 궁극적으로는 Fission Gas Bubble에 의한 Swelling을 저감시킬 것으로 기대된다.

• 대한치과의사협회지
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• 제58권2호
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• pp.103-113
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• 2020

Background: Reduction malarplasty is one of the most popular facial contouring surgeries in east Asia for making patients' faces smaller. Currently in Korea, reduction malarplasty surgeries are performed mostly at plastic surgery clinics, but few cases are done at oral and maxillofacial surgery clinics. The reason might be because of post-operative complications after reduction malarplasty, such as undercorrection, overcorrection, asymmetry, cheek drooping, malunion, pain and noise. Those complications should be uneasy to be handled by oral and maxillofacial surgeons, however, they can be prevented by knowing the effective and safe reduction malarplasty techniques. Therefore, in this article the author as an oral and maxillofacial surgeon, would like to suggest safe and effective surgical methods for reduction malarplasty customized for Korean patients. Method: L- shape osteotomy of zygomatic body was performed with intraoral approach via vestibular incision, and the zygomatic arch was osteotomized with extraoral approach via sideburn incision. Then zygomatic complex was separated and rotated mesio-superiorly without removal of a bony strip and fixed with miniplates and microplates without making a bony gap. Conclusion: Surgical results were favorable and satisfied by the patients without cheek drooping, malunion, undercorrection and asymmetry.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1997년도 춘계학술발표회논문집(2)
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• pp.177-182
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• 1997

금속연료가 연소할 때 발생하는 Fission Gas는 주로 직경방향으로의 Swelling을 일으켜 낮은 연소도의 원인이 되어 왔다. 따라서 본 연구에서는 높은 연소도를 갖는 금속연료의 개발을 목적으로 Fission Gas가 Plenum으로 쉽게 방출하는 조직인 Laminar Structure를 갖는 합금의 설계를 연구하였다. 또한 조사 후의 조직안정성을 예측하기 위해 열처리 후의 미세조직의 변화를 관찰하여 조직안정성을 시험하였다. U-10wt.%Zr 합금 중 Zr 원소 대신에 2wt.% 및 3wt.%의 W 또는 Mo을 첨가한 합금을 제조하여 합금원소 첨가의 영향에 따른 미세조직의 변화를 조사하였다. 그 결과 모든 조성의 합금은 Matrix에 있어서 Laminar Structure를 나타내었다. 또한 U-10wt.%Zr에 비해 2wt.% 및 3wt.%W의 W 또는 Mo를 첨가한 합금의 lamina Thickness가 철면 미세해짐을 확인하였다. 특히 U-7wt.%Zr-3wt.%W의 경우는 U-10wt.Zr에 비해 Laminar Thickness가 1/2배까지 감소되었다. 합금원소(W, Mo) 첨가에 의한 Laminar Thickness의 감소는 Fission Gas의 Inter-connected Path가 보다 잘 형성되게 하여 Gas의 방출속도를 증가시켜 Swelling을 감소시킬 것으로 생각된다. 열처리한 금속연료의 미세조직을 비교한 결과를 보면 합금원소(W, Mo)를 첨가한 합금을 50$0^{\circ}C$에서 1000시간동안 열처리한 것을 U-Zr 2원계 합금을 열처리한 것과 비교했을 때 약 1/3배 정도의 Laminar Thickness를 유지하는 것으로 보아 합금원소를 첨가하면 조사 후의 조직안정성에도 크게 기여할 것으로 기대된다.

• 드라이브 ㆍ 컨트롤
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• 제20권3호
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• pp.25-34
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• 2023

In this study, we conducted a research on optimizing the spraying performance of agricultural drones and predicted the spraying performance in various flight conditions using the multi-layer perceptron (MLP). Data was collected using a test device for pesticide spraying performance according to the water sensitive paper (WSP) evaluation. MLP training involved supervised learning to achieve a coefficient of variation (CV), which indicates the degree of uniform spraying. The performance evaluation was conducted using R-squared (R²), the test samples showed an R² of 0.80. The results of this study showed that drone spraying performance can be predicted under various flight environments. In addition, the correlation analysis between flight conditions and predicted spraying performance will be useful for further research on optimizing the spraying performance of agricultural drones.

• 한국지리정보학회지
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• 제8권2호
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• pp.117-124
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• 2005

산불관리에 있어서 산불발생위험이 높은 지역을 사전에 예측하여 효율적인 예방대책을 수립하는 것도 중요하지만 산불이 발생한 다음 대형화되기 쉬운 지역을 미리 예측하여 진화자원을 효율적으로 운용하여 초동진화를 한다면 산불로 인한 피해를 저감할 수 있다. 따라서 본 연구에서는 산불관리의 효율성을 증대하기 위하여 GIS를 이용하여 기존에 지형, 임상 특성 등을 이용한 산불 발생위험지역을 예측한 것과 임상특성을 고려하여 산불이 대형화되는 지역을 구분한 결과를 바탕으로 산불 발생 및 대형화 위험성이 높은 지역을 구분하였다. 구분한 결과 전체면적 중 4%가 산불 발생 및 대형화 위험지역으로 구분되었다.

• Journal of Preventive Medicine and Public Health
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• 제34권3호
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• pp.200-210
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• 2001

Objective : To explore the status of cancer research in the Republic of Korea. Methods : Thirty-eight medical journals, published in Korea between 1990 and 1996, were reviewed for abstracts relating to cancer research. Of the 5,899 eligible abstracts related to cancer, 4,732 were collected and evaluated. Results : Including first author and first two co-authors, a total of 7,427 authors were identified. Those who published an average of one or more article per one year were defined as cancer researchers for this study. This group, however, accounted for a small proportion of the total (3.1%). Analysis of the selected abstracts showed that the study goals in more than half focused on pathophysiologic mechanisms. Studies that were designed to use causal relationships such as cohort studies and randomized controlled trials were rare. A greater number of analytic and experimental studies were found in abstracts published by the cancer researcher group. More advanced study designs that explored causal relationships and analytic procedures were found in abstracts published later than those abstracts published from 1990 to 1992. Conclusion : Our findings show that researchers who published more articles adopted more advanced study designs. This study provides primary data that can be used to compare the status of cancer research in future studies.

• 대한치과마취과학회지
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• 제3권2호
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• pp.98-102
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• 2003

Patients in end-stage renal disease (ESRD) and chronic renal failure present a number of challenges to the anesthesiologist. They may be chronically iii and debilitated and have the potential for multiorgan dysfunction. A 65-year-old male patient with ESRD was scheduled for oral cancer surgery under general anesthesia. He was in regular hemodialysis three times a week and secondary hypertension with left ventricular hypertrophy was accompanied. He also had chronic metabolic acidosis and hyperkalemia. The day after hemodialysis, general anesthesia was carried out. Uneventful anesthetic induction using thiopental and vecuronium and nasotracheal intubation were carried out. General anesthesia was maintained with isoflurane for 9 hours. During the anesthesia, he did not have any problem but persistently increasing serum potassium level. After anesthetic emergence, he was transferred to intensive care unit for mechanical ventilation. So we report this successful case of anesthetic management in a patient with ESRD for oral cancer surgery, which massive bleeding and long anesthetic time were inevitable in, from the preoperative preparation to anesthetic emergence.

• Journal of Preventive Medicine and Public Health
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• 제32권4호
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• pp.546-555
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• 1999

Objectives : To determine the prevalence, pattern. and out-of-pocket expenditure of complementary and alternative medicine (CAM) utilization in Korean adult population. Methods : We conducted a representative telephone survey of 2,042 persons aged 18 or older. Data about any health problem, details of their use of medical doctors(MDs) offices/hospitals/pharmacies services and CAM during the preceding 12 months were collected with structured questionnaire. Results : The utilization rate of CAM among Korean adults was 29% in one year. A total of 231 kinds of CAM was identified from this survey. Annual out-of-pocket expenditure associated with CAM use in 1998 amounted to ${\xi}{\S}1.88$ billion and was comparable to 40.8% of out-of-pocket expenditure paid for MDs offices/hospitals/pharmacies services. Among those(N=424) who paid for both MDs offices/hospitals/pharmacies services an d CAM, 35.8% paid more for CAM. CAM gave more satisfaction than western medicine to those who had experience of both types of therapy. About half of CAM users were willing to recommend CAM to others. Disclosure rate to physician among CAM users was not high(40.6%). Conclusion : CAM became a popular source of health care in Korea, Korean spent a substantial amount of out-of-pocket money on CAM without any public control. Because CAM use is likely to be increased rapidly through lay referral system, health policy makers and health professionals should pay more attention to CAM for making appropriate utilization of CAM.

• Journal of Preventive Medicine and Public Health
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• 제31권4호
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• pp.844-856
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• 1998

Globally, cancer research has been considered one of the most important field of biomedical researches. Recently, in Korea, there are increasing concerns about cancer research and the development of national cancer control programme. For the efficient investment in cancer research at the national level, strategic approach is needed based on the nationwide information about current status of research. However even the basic data on cancer research have not been systematically collected, and are not available when necessary. The aim of this study is to assess current status of cancer research. For this purpose, this study applied two round Delphi method in which fifteen experts in cancer research fields participated. They rated each items on the initial list at the first round, and modified their responses at the second round. Panels responded that pathogenesis of cancer, research & development of cancer drug, and oncogene, etc. are the most urgent and important research Holds. They assessed national level of cancer research as being 49.6% of the world highest level. Coefficient of variation tended to be lowered with the iteration. Predictive stability was evaluated to be lower in items of urgency than in items of importance and research level. Although this study shares the same limitations in the selection of the experts with many other Delphi studies, it provides a primary data that would be required to plan the national strategy of the cancer research.

• 방사성폐기물학회지
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• 제5권1호
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• pp.1-7
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• 2007

흑연음극을 이용하여 LiCl-KCl공융염내에서 금속우라늄의 전해정련을 수행하였다. Uraniurn-Graphite Intercalation Compound(U-GIC)의 형성에 의하여 우라늄 전착물의 sell-scraping이 일어나며 전해정련에서 stripping과정을 생략함으로서 전해효율을 높일 수 있다. 우라늄 전착물내의 희토류 원소 오염은 무시할 만 하였으나 약 300ppm정도의 탄소가 오염되어 있는 것으로 관찰되었다. 탄소 오염은 이트륨을 이용한 정제공정 등을 거칠 경우 제거 가능하리라 사료된다. 회수된 우라늄 전착물의 조직 특성을 분석하였으며, 스틸 음극에 의해 회수된 전착물과 비교하였다. 이 결과는 초기 실험결과 이며 보다 심층적 연구를 통하여 사용 후 금속핵연료의 전해정련 개념을 개선시킬 수 있을 것으로 판단된다.