Ni-ZnFerrite의 磁氣的 特性에 미치는 燒結온도의 영향

尹志洪,朴奎殷,金奎用 제주대학교 1982 논문집 Vol.14 No.-

Ni-Zn Ferrite는 1200℃이상의 온도에서는 소결성이 좋으며 Bi₂O₃를 첨가하여 소결한 것은 1250℃에서 최대투자율 2050을 얻었으며 보자력은 0.13 Oe로서 가장 낮은 값을 나타내었다. 그러나 주파수에 따른 초투자율은 높은 주파수 영역에서는 다른 조건에서 소결시킨 시료에 비하여 낮은 값을 가진 것으로 나타났다. 사용되는 주파수의 영역에 따라서 적절한 소결온도, 적절한 첨가물이 결정될 수 있을 것으로 예상된다. The magnetic properties of Ni-Zn ferrites with additive(Bi₂O₃;0.3wt%)and without additive have been measured. The maximum permeability is 2050, the initial permeability is 1538 at 1.55MHz and the coersive force is 0.130Oe.

특발성 자발성 신장 파열 1예

윤재철,김원,조규종,홍정석,이미우,장성은,오세현,임경수 대한응급의학회 2001 대한응급의학회지 Vol.12 No.4

Primary aldosteronism is a syndrome characterized by hypertension, hypokalemia, suppressed plasma renin activity, and elevated serum aldosterone levels. Conn first described it 1955 in association with adrenal cortical adenoma(Conn's syndrome). Today, it can be divided into at least six distinctive sub-groups. The diagnosis of primary aldosteronism is usually suspected when the patient presents with poorly controlled hypertension with hypokalemia. The main issues in the evaluation of primary aldosteronism are to differentiate an adenoma from hyperplasia and to localize the adenoma. Basic hormonal studies and computed tomographic(CT) scanning can be used effectively for that differentiation. An adenoma is one of a few potentially curable forms of hypertension, and it is best treated by removing the adrenal tumor. We experienced a case of a typical adrenal adenoma. The patient was a 37-year-old male who had experienced in both his legs over a period of several days a weakness due to hypokalemia. He was diagnosed using basic hormonal studies and adrenal CT scanning. After, he received laparoscopic adrenalectomy and was discharged with improved condition.

금속철 및 산화철의 K - 흡수단 미세구조에 관한 연구

박규은,박종윤 濟州大學校 師範大學 科學敎育硏究所 1984 科學敎育 Vol.1 No.-

The K-edge absorption spectra of Fe and FeO are measured by X-ray absorption spectroscope Comparisons to theory are made for both the Fe and FeO data. We attempt to interpret origins of the spectral near-edge structure. For themetal Fe, We find agreement between the data and one-electron calculations. Peaks of near edge structure of FeO can not explain with one-electron transition model. For explanation of these peak, we find that the core-exciton and many-body effects must be taken into account. From the extended X-ray absorpticn fine structure (EXAFS), we determined distance to the nearest neighbour. The results agree with the value from the X-ray diffraction experiment.

뇌파의 비선형적 분석을 위한 Tool 개발

최윤정,한운섭,최경규 이화여자대학교 의과대학 2003 EMJ (Ewha medical journal) Vol.26 No.2

연구목적 : 본 연구는 비선형 동역학 이론을 이용하여 뇌파를 시공간적으로 분석해 내고 이를 지능형 시스템에 도입함으로써 새로운 진단시스템을 개발하는 것을 목적으로 한다. 방법: 최대 64 채널가지의 모든 뇌파에 대해 적용이 가능한 시스템을 구성하여 가장 기본적인 형태의 뇌파 샘플을 적용, 측정된 뇌파를 불러오고 전처리 과정을 통해 신호를 분석에 용이하게 가공하고 분석법의 특성에 따라 알맞은 분석법을 선택하여 분석하고 분석된 데이터는 후처리과정을 통해 그 패턴을 분류하는 단계의 프로그램을 만들고 비선형 동역학 이론을 이용하여 단계별 프로그램을 구성하였다. 결과: 컴퓨터 시스템에 사용하는 프로그램을 다음과 같은 다양한 요소로 구성하였다. 신호 발생부에는 Lorenz sys-tem과 Rossler system을 포함하였다. 신호 전처리 부에는 정량화, 밴드 패스 필터링, 잡음 추가, 미분, sutto-gating 과정을 포함하였다. 신호 분석 부에는 스펙트럼분석, 위상공간 분석, 상관 분석, 모드 분석을 포함하였다. 신호 후처리 부에는 setting layer, Learning procce-ssing and Making weight file, Classifier start with Test file을 포함하였다. 부가기능으로서 Copy&paste, Print, Save 기능을 포함하였고 운영 환경은 Windows 95/98/2000 또는 Windows NT를 사용하고 데이터 형식은 뇌파 채널 최대 64채널까지 가능(Neural Network Processing의 경우 8채널) 하며 아스키 파일로 열(co-lumn)의 수는 채널을 의미하고 행(row)은 샘플링되어 저장된 데이터를 의미하는 것으로 하였다. 결론: 뇌에서 발생하는 전기학적 신호를 실시간으로 손쉽게 분석하여 실제 진단에 이용할 수 있는 기본적인 컴퓨터 프로그램을 개발하였으며 이를 토대로 더욱 정교하고 객관적인 뇌파 분석 결과를 얻을 수 있는 상용 프로그램의 개발에 이용할 수 있을 것으로 생각한다. Objectives : EEG is a record of electronic signals of brain. If there are effective methods for analysis of EEG signal it can be used as a diagnostic tool for diseases related to brain function. We developed a new a basic computer program which was designed to analysis of pattern of EEG. For nalysis of pattern, EEG signal was processed by variable experimental analytical methods and grouped by common pattern. Results : Program was composed of multiple systems. Signal generating system was composed of Lorenz signal generation and Rossler signal generation parts. EEG processing system was com-posed of Normalization, Band pass filtering, First Second difference, Add random noise and Sur-rogate making parts. EEG analyses system was composed of Spectral analyses, Phase space analyses, Correlation analyses and Mode analyses parts. Pattern recognition and grouping system was com-posed of data format, Power spectrum, Neural network process and Classification parts. Conclusion : We developed a basic computer program for systemic analysis of EEG by Nonlinear analysis methods.

장기입원환자 관리 방해요인

이경석,윤석만,권희,이호,김혜경,조미자,한규남,김명성 순천향의학연구소 2003 Journal of Soonchunhyang Medical Science Vol.9 No.1

Background: Recently the health insurance review agency tried to cut off the cost of unnecessary hospital stay. It is important to reduce the prolonged occupation of the hospital beds. However, there are some obstacles of the management for the prolonged bed occupation. We report our experiences and the problems of bed-control. Methods: To increase the rate of effective bed-usage, a task force was made. This team was consisted of 4 dctors, 2 nurses and 2 personnel of the administrative department. From December 20th 2001 to May 17th 2002, the task force analysed the rate, number and causes of the prolonged (more than 60 days, regardless of the disease entities) bed occupation. We announced and explained the necessity of bed-control and actively pressed to reduce the prolonged bed occupation. Results: The number of the prolonged bed occupation was 71 at the beginning of the management. It was reduced to 46 at best, then turned back to 65 at the end. It seems to be impossible to reduce the prolonged bed occupation until there are sufficient numbers of long-term care facilities. Aggressive bed control makes the sick patients to move every two or three months, it is never desirable. Conclusion: We cannot expect any Quality Improvements without improvement of the wrong system. Prior to the management for the prolonged bed occupation, it is necessary to build a sufficient number of long-term care facilities.

Kerr-Lens 모드-록킹되는 티타늄 사파이어 레이저의 대칭형 공진기의 설계와 안정성에 대한 분석

추한태,윤병운,김규욱,이태동 금오공과대학교 산업기술개발연구원 2001 産業技術開發硏究 Vol.17 No.-

Design and theoretical analysis for the spot size and the Kerr-lens mode-locking(KLM) strength can be represented as explicit function of the position in the cavity, the intracavity laser power, and the stability parameter for symmetrical Z-type laser cavity with a four-mirror. The results indicate that the KLM strength achieves its maximum value at the edge of the stability range. Self-amplitude modulation and group-velocity dispersion compensation can be established by using of the intraprism path length and the separation of a prism pair for beam path in the cavity. Also we have compared above theoretical results with the experimental data for our KLM Ti:sapphire laser system, and can obtain the pulse width of 25.7 fs with the FWHM of 33 nm and the repetition rate of 82 MHZ.

이층지반과 단일지반의 열전달 거동 특성 평가

윤석(Seok Yoon),박스칸(Skan Park),박현구(Hyun-Ku Park),고규현(GyuㅡHyun Go),이승래(Seung-Rae Lee) 한국지열·수열에너지학회 2011 한국지열에너지학회논문집 Vol.7 No.2

This paper presents how to analyze heat transfer characteristics of double-layered soils. Thermal response tests were conducted to measure the ground thermal conductivities of Joomunjm sand and douole layered soils filled in a steel box of which the size is 5m × 1m × 1m. Double-layered soils were composed of Joomunjm sand and Kaoline clay. Each Lhermal conductivity of Joomurym sand and Kaloine clay was measured by using Heat Flow Meter considering different void ratio. The ground thermal conductivity of doubleㅛlayered soils was 15% smaller than that of Joomunjin sand.

茶 침출조건에 따른 Catechin, 무기질 및 Vitamin C 함량 변화

이순재,김미지,윤연희,박규영,최원경,방진숙,부용출 대구효성가톨릭대학교 응용과학연구소 1994 응용과학연구논문집 Vol.3 No.-

본 연구에서는 실제 상용하고 있는 각 차음료가 온도, 시간 및 추출 횟수에 따른 성분의 함량의 차이를 관찰코져 시판되고 있는 한국산 녹차, 우롱차 및 홍차를 대상으로 추출방법을 달리한 후 茶浸出液중의 주요성분인 catechin, vitamin C 및 여러가지 무기질의 함량을 측정하여 다음과 같은 결과를 얻었다. 1. 차침출온도에 따른 침출액중의 catechin과 vitamin C 함량의 차이를 볼 때 온도가 높을수록 많이 추출되었다. 2. 같은 온도라는 침출시간에 따른 차이를 관찰한 결과 시간이 길수록 침출액중의 catechin과 vitamin C의 함량이 증가되었다. 3. 녹차는 우려낸 횟수에 따른 catechin의 함량 차이는 처음에 비하여 2회 추출시약 51%, 3회추출시는 71% 감소하였다. 4. 차의 각 무기원소에 따른 함량을 비교시 Mg은 우롱차가 가장 높고 K, Mn은 녹차가, Zn, Cu 그리고 Fe는 홍차가 가장 높게 나타났다. 5. 녹차, 우롱차의 경우 대체로 무기질의 침출정도가 온도가 높을수록 오히려 감소하는 경향을 나타내었고 홍차는 Mg, K을 제외하고 모두 증가하였다. 6. 각 침출액중의 대부분의 무기질 함량은 추출횟수가 증가할수록 감소하였다. 7. 시료로 사용한 녹차, 우롱차, 홍차의 vitamin C 함량은 녹차, 우롱차, 홍차의 순으로 높게 나타났다. 8. 녹차를 추출한 횟수에 따른 vitamin C 함량은 1회에 비해 2회 추출시 약 36%, 3회 추출시 약 62% 감소되었다. 9. 5g의 녹차를 80℃에서 2분간 침출한 액중에서는 catechin은 100ml당 0.34g, Mg은 2.229mg, Ca은 0.365mg, K은 39.77mg, Zn은 0.037mg, Cu은 0.010mg, Fe는 0.001mg, Mn은 0.581mg이며, vitamin C는 9.65mg이 함유되어 있었다. This study was to compare the ingredients which are contained in usual Korean teas in-depednence on leaching temperature, time and number. The main contents i.e. catechin, vi-tamin C and other minerals extracted from Korean commercial green tea, oolong tea and black tea were measured. The resluts are as follows; According to extracting temperature, the higher temperature made catechin and vitamin C extracted more. For the same leaching temperature, the longer time the more catechin and vitamin C. In case of extracting number, the contents of catechin was decreased a-bout 50% and 70% at second time and third, respectively in comparasion to the first time. For minerals from teas, management(Mg) was most in oolong tea, potassium(K)and manganease(Mn) and in green tea and iron(FEe) was in black tea respectively. Most min-erals from greentea and oolong tea were extracted less as leaching temperature was in-creased. But in black tea minerals other than Mg and K were more at increased tempera-ture. Most minerals in extractions were decreased as leaching number was increased. The content of vitamin C in the experimental samples(tea) was most in green tea, next in oo-long tea and third in black tea. In comparasion with the first extraction vitamin C was de-creased about 35% and 60% at 2nd and 3rd leach, respectively.

성인 급성 신부전의 원인 및 예후인자 분석

구영선,장윤경,양종오,강민규,황평주,김종학,나기량,이강욱,신영태 충남대학교 의과대학 지역사회의학연구소 1998 충남의대잡지 Vol.25 No.2

Acute renal failure is a frequent complication in hospitalized patients and is strongly related to the mortality. The Clinical outcome and prognostic factors of acute renal failure(ARF) have been analyzed by many authors. The present study describes the etiologic and clinical aspects, as well as other factors related to mortality. All the patients suffering from acute renal failure admitted during the period of January 1993 - August 1998 were included in the study. The average age of the patients was 52±17 years and mortality rate was 24%. The causes of acute renal failure were hemorrhagic fever with renal syndrome(HFRS), sepsis, renal hypoperfusion, urinary tract obstruction, acute tubular necrosis, etc. The etiology of ARF was a significant prognostic factor on mortality in ARF. Other significant prognostic factors were oliguria, organ failure, use of vasoconstrictors, hypotension, serum bicarbonate, premorbid conditions, sepsis, neurologic complications, gastrointestinal bleeding. On the other hands, operation, sex, anemia, thrombocytopenia, hypoalbuminemia, BUN, serum creatinine, and hyperkalemia were not significant factors for the mortality. We conclude that major prognostic factors of acute renal failure arc premorbid conditions, sepsis and multiorgan failure, and they are responsible for persistent high mortality of acute renal failure despite of advances of medical care.

한랭노출과 고혈압의 연관성

장태원,김윤규,윤동영,이창희,홍영습,신해림,정갑열,김준연 大韓産業醫學會 2001 대한직업환경의학회지 Vol.13 No.4

Objectives : This study was carried out to suggest preventive methods for hypertension in cold-exposed workers. Methods : In 11 refs·iteration industries, 68 workers working in refrigerated areas more than one time per day were selected as the exposed group, and 68 workers not exposed to cold were selected as the control group. We interviewed the subjects with a questionnaire covering occupational history, and conducted clinical and laboratory tests including measurements of blood pressure and core temperature. Results : The systolic blood pressure in the exposed group(130.0±13.3 mmHg) was significantly higher than that recorded In the control group(118.3±12.1 mmHg), as was the diastolic blood pressure in the exposed group(82.7±8.5 mmHg) versus the control group(77.4±8.7 mmHg). The core temperature in the exposed group(36.1±0.7℃) was significantly lower than that experienced in the control group (36.4±0.5℃). In logistic regression analysis, age, cold exposure severity and milk intake were significant variables, with odds ratios of 5.204(95 % CI 1.440∼18.812), 2.674(95 % CI 1.080∼6.618), and 0.364(95 % Cl 0.141∼0.942) , respectively. Conclusions : Our study suggests that cold-exposed workers have higher a higher risk of hypertension, and that their core temperature is lower. Risk factors affecting hyper-tension of cold-exposed workers include age, cold exposure severity and milk intake. For the prevention of hypertension, cold-exposed workers should minimize cold-exposure time as much as possible.