플라즈마 세정기술 현황

남기석 한국열처리공학회 2003 熱處理工學會誌 Vol.16 No.3

시간-주파수 해석법에 의한 CFRP의 파괴 거동

남기우,안석환,이상기,김현수,문창권 한국비파괴검사학회 2001 한국비파괴검사학회지 Vol.21 No.1

신호처리법으로 현재 많이 사용되고 있는 푸리에 변환은 신호의 주파수 성분이 사간에 따라 어떻게 변화하는지를 표현하지 못한다. 따라서 최근 이와 같은 푸리에 변환의 단점을 보완하여, 신호의 시간과 주파수에 대한 정보를 동시에 표현할 수 있는 시간-주파수 해석법들이 개발되었다. 본 연구에서는 음향방출을 이용하여 복합재료의 주요 발생원으로 알려져 있는 기지균열, 섬유분리, 섬유파괴 및 층간분리 등과 같은 파괴기구를 해석하였다. 각각의 파괴특성이 나타나도록 시험편을 제작하여 인장시험 시 검출된 음향방출신호의 시간-주파수 해석을 통해 전체 파괴기구의 특징을 분석하였다. Fourier transform has been one of the most common tools to study the frequency characteristics of signals. With the Fourier transform alone, however, it is difficult to tell whether signal's frequency contents evolve in time or not. Except for a few special cases, the frequency contents of most signals encountered in the real world change with time. Time-frequency analysis methods are developed recently to overcome the drawbacks of Fourier transform, which can represent the information of signals in time and frequency at the same time. In this study, damage process of cross-ply carbon fiber reinforced plastic (CFRP) under monotonic tensile loading was characterized by acoustic emission. Different kinds of CFRP specimens were used to determine the characteristics of AE signals. Time-frequency analysis methods were employed for the analysis of fracture mechanisms in CFRP such as matrix cracking, debonding, fiber fracture and delamination.

대기압 플라즈마기술 현황

남기석 한국열처리공학회 2003 熱處理工學會誌 Vol.16 No.4

3차 의료기관에 입원한 노숙환자에서 감염질환의 유병율

함세운,남기석,노혜진,홍경득,황래석,방지환,신형식 대한감염학회 2007 감염과 화학요법 Vol.39 No.4

목적 : 3차 의료기관에서 입원치료를 받았던 노숙자를 대상으로 감염성 질환의 유병율을 알아보고자 하였다. 재료 및 방법 : 2002년 1월부터 2004년 8월 사이에 국립의료원에서 입원 치료를 받았던 269명의 노숙자 환자들을 대상으로 의무기록을 조사하였다. 결과 : 연구 기간동안 입원치료를 받은 총 269명의 노숙자 환자 중 남자가 249명(92.9%), 여자가 19명(7.1%)이었다. 감염질환의 유병율은 B형 간염이 228명 중 15명(6.6%), C형 간염 113명 중 8명(7.1%), 결핵은 269명중 19명(7.1%), VDRL 양성인 경우는 234명 중 25명(10.7%), 항사람면역결핍바이러스항체 양성은 130명중 2명(1.5%)이었다. B형 간염표면항원에 대한 항체 형성자는 118명(51.7%), 항체 미형성자는 95명(41.7%)이었다. 결핵으로 진단된 19명 중 객담도말 및 배양검사와 조직검사로 확인된 경우가 14명, 균음성이나 임상적으로 의심되는 경우가 5명이었다. 간질환 및 관련된 합병증으로 입원한 환자 28명 중 B형 및 C형 간염바이러스에 관련된 경우는 5명(17.9%)에불과하였고 결핵은 19명중 13명(68.4%)이 폐결핵 및 림프절종대의 증상으로 입원치료를 받았다. 복합 감염의 경우는 총 9명이었는데 후천면역결핍증후군 환자였던 2명중 1명이 결핵에 이환되어 있으면서 VDRL 양성소견을 보였고 다른 1명이 HIV와 결핵의 동시감염이었다. 결론 : 노숙자 입원환자에서 결핵, C형 간염 및 매독의 유병율이 일반 인구에 비해 높았다. 노숙자환자를 담당하는 의료인력를 보호하고 환자의 감염질환 유무를 파악하기 위해 적절한 선별검사가 필요하며 감염질환의 확산을 방지하기 위한 정부의 적극적인 대책이 필요하다. Background : Despite the expected high prevalence of several infectious diseases among the homeless, a majority of them have not received screening test and early treatment. Materials and Methods : The subjects of this study were 269 homeless patients who had been hospitalized in the National Medical Center (Korea) between January 2002 and August 2004. Their medical histories and records were reviewed to analyze the prevalence and clinical characteristics of hepatitis B and C, syphilis, tuberculosis and HIV infection among them. Results : The entire 269 homeless patients being hospitalized during the period of this study consist of 249 male patients and 19 female patients. For the prevalence of infectious diseases, HBV was seen in 15 of 228 patients (6.6%); HCV in 8 of 113 patients (7.1%); VDRL positive in 25 of 234 patients (10.7 %); HIV antibody positive in 2 of 130 (1.5%); and tuberculosis in 19 of 269 (7.1%). The number of patients who had the antibody to hepatitis B was 118 (51.7%). Of 28 patients hospitalized with the chief complaints of liver diseases and/or their complications, the number of cases infected with hepatitis B and C viruses was only 5 (17.9%). On the other hand, for patients with tuberculosis, 13 of 19 cases (68.4%) were hospitalized with the chief complaints associated with symptoms of pulmonary tuberculosis or enlarged lymph nodes. The number of patients with multiple infectious diseases was 9 in total. Conclusion : As expected, the prevalence of some infectious diseases were higher among the homeless inpatients, than non-homeless population. Proper screening tests in order to determine the presence of any infectious diseases among the patients and protect involved medical staff are necessary. Further, the government should take proactive measures to prevent the spread of infectious diseases in the aspect of public health.

복어중독에 의한 가사 상태에서 소생한 1예

송승찬,신진호,강석우,박경남,최호순,박근태,문희식,기춘석,이성희,윤병철,노우균,조균석,이민호 大韓應急醫學會 1998 대한응급의학회지 Vol.9 No.3

Tetrodotoxin is a neurotoxin produced by about 90 species of puffer fish and causes paralysis of central nervous system and peripheral nerves by blocking the movement of all monovalent cation. Ingestion of tetrodotoxin produces clinical manifestations such as paresthesias(within 10-45 min), vomiting, lightheadedness, salivation, muscle twitching, dysphagia, difficulty in speaking, convulsion and death that expressed by cardiopulmonary arrest with loss of brain stem reflex sometimes. Tetrodotoxin prevents or delays ischemia induced neuronal death by way of following 3 mechanisms. Firstly, it reduces the energy demand of the brain tissues. Secondly, it delays or even prevents anoxic depolarization. Finally, it deminishes ischemia induced cell swelling and cerebral edema. We report a case of puffer fish poisoning which presented with cardiopulmonary arrest and loss of brain stem reflex, but completely recovered by aggressive cardiopulmonary resuscitation.

익수환아의 예후에 영향을 미치는 인자에 관한 연구

김용배,정대봉,조수형,조남수,박영봉,박상기,김춘호,양은석,문경래 大韓應急醫學會 1998 대한응급의학회지 Vol.9 No.3

Drowning is the second most common cause of accidental death of children in Korea. But the study of near-drowning is very rare in Korea. The purpose of our study is to determine the factors that may influence survival on the basis of submersion time, consciousness state upon admission to hospital, the kinds of water, laboratory findings and neurological outcomes. The survey was performed by a retrospective cohort study on 28 near-drowning victims of less than 15 years of age who were admitted to the emergency room in the Chosun University Hospital between May 1988 & May 1997. The results were as follows :1)Sex distribution was 22 males and 6 females. 2) Submersion time was <5 minutes in 9 cases, 5-9 minutes in 6 cases, 10-14 minutes in 5cases, 15-19 minutes in 3 cases, ≥20 minutes in 5cases. 3) Comatose patients upon arrival were 6/7 cases in the death group(86%) and 2/21 cases in the improved group(10%). They had unfavorable outcomes(P<0.05). 4) The first PH value was mean 7.02±0.12 in the death group and mean 7.31±0.13 in the improved group. There was a statistically significant difference between the death and the improved group(P<0.05) 5) The patients who gad increased blood glucose concentration were all 7 cases in the death group and 12/22 cases in the improved group(54%). The mean blood glucose concentration was mean 424.7235.6㎎/㎗ in the death group and mean 140.182.7㎎/㎗ in the improved group. There was a statistically significant difference between the death and the improved group(P<0.05). 6) The patients who had pulmonary edema upon arrival were all 7 cases in the death group and 1/21 cases in the improved group(46%). They had unfavorable outcomes(P<0.05). 7) The patients who had been submerged more than 15 minutes were all 7 cases in the death group and 6/21 cases in the improved group(5%). They had unfavorable outcomes(P<0.05). We conclude that pediatric victims of near-drowning can be assigned to high or low likelihoods of unfavorable our outcomes with the use of five variables ; comatose mentation upon arrival decreased initial blood pH, increased initial blood glucose concentration, pulmonary edema, and maximum submersion time estimated longer than fiften minutes. This prediction rule may be useful if it can be validated in another cohort.

부산지역 전복 종자방류사업의 경제적 효과 분석

곽석남(Seok-Nam KWAK),김성수(Sung-Soo KIM),김현승(Hyun Seung KIM),기희석(Hee Suk KEE),신상희(Sang Hee SHIN),남주희(Ju Hee NAM),한지성(Ji Sung HAN),이원세(Won SE LEE),김두호(Do Ho KIM),최종국(Jong-kuk CHOI),홍재범(Jae-Beum HONG),김도훈(D 한국수산해양교육학회 2023 水産海洋敎育硏究 Vol.35 No.6

플라즈마를 이용한 표면경화기술 현황

남기석(Kee Seok Nam),권식철(Sik Chol Kwon),김성완(Sung Wan Kim) 대한금속학회 1999 大韓金屬學會會報 Vol.12 No.6

IEC 61850 Ed 2 데이터 특성과 스키마 변경 분석 및 Ed 1-2 연계 엔지니어링 방안 고찰

김석곤(Seok-kon Kim),이남호(Nam-ho Lee),김남대(Nam-dae Kim),이유진(You-jin Lee),안용호(Yong-ho An),장병태(Byung-tae Jang),최종기(Jong-kee Choi),신성식(Seong-sik Shin),심현석(Hyun-seok Sim) 대한전기학회 2019 대한전기학회 학술대회 논문집 Vol.2019 No.7

Serum osteocalcin levels in overweight children

Seok Bin Oh,Won Young Lee,Hyo-Kyoung Nam,Young-Jun Rhie,Kee-Hyoung Lee 대한소아내분비학회 2019 Annals of Pediatirc Endocrinology & Metabolism Vol.24 No.2

Purpose: Bone plays a role in glucose metabolism through the release of uncarboxylated osteocalcin into the systemic circulation. The identified novel roles for osteocalcin include increasing insulin secretion and sensitivity, energy expenditure, reduction of fat mass, and mitochondrial proliferation and functional enhancement. This study aimed to determine serum osteocalcin levels in overweight children and to investigate the relationships of osteocalcin with glucose metabolism and insulin sensitivity. Methods: After overnight fasting, serum osteocalcin levels were measured in overweight (n=50) children between 6.0 and 12.9 years of age and nonoverweight controls (n=60). Height, weight, fasting serum glucose, insulin, alkaline phosphatase, total cholesterol, and 25 hydroxy vitamin D3 (25(OH)VitD3) were also measured in all subjects. Results: There were significant differences in serum osteocalcin levels between the overweight and control groups (64.00±20.44 vs. 89.56±28.63, P<0.001). Serum osteocalcin levels were inversely correlated with body mass index (BMI) (r=-0.283, P=0.003), weight standard deviation score (SDS) (r=-0.222, P=0.020), BMI SDS (r=0.297, P=0.002), insulin (r=-0.313, P=0.001), and homeostasis model assessment of insulin resistance (HOMA-IR) index (r=-0.268, P=0.005). In the subsequent multiple regression analyses, BMI, HOMA-IR, and age were determined to be independent predicting factors for serum osteocalcin. Conclusion: Our findings showed associations of serum osteocalcin with glucose metabolism and insulin sensitivity in overweight children, but we could not establish a causal relationship.