Superconducting MgB2 Wire Drawing Considering Anisotropic Hardening Behavior and Hydrostatic Effect

Young‑Seok Oh,Ho Won Lee,Kook‑Chae Chung,Duck‑Young Hwang,Seong‑Hoon Kang,Jeong Whan Yoon 대한금속·재료학회 2022 METALS AND MATERIALS International Vol.28 No.7

Numerical modeling was conducted to investigate the deformation behavior of powder mixture during multi-pass drawingprocesses for multi-filamentary MgB2wire. A modified Drucker-Prager Cap (DPC) model with an elliptical cap surface usingthe new material characterization method was developed to capture the anisotropic hardening behavior and hydrostatic effectof the powder mixture. A number of uniaxial die compaction, cold isostatic pressing, diametrical compression, and uniaxialcompression tests were conducted using different powder densities to characterize the modified DPC model. A commercialfinite element software ABAQUS with a user subroutine was used to simulate the drawing of the MgB2wire. The densityand area fraction of the powder mixture during the wire-drawing process were verified with experimental results. The differencein packing density at the inner and outer filaments of the MgB2wire was successfully captured by simulation. Inaddition, the effect of the initial packing density on the superconducting properties of MgB2wire was numerically studied. It is shown that the increase in the superconducting area, which results from a high initial packing density, should be moreeffective compared to the increase in the grain connectivity in enhancing the critical current properties for the MgB2wirewhen the final packing density is saturated after a number of drawing processes.

정신분열병에 대한 리스페리돈의 효과 및 안정성

이민수,김용구,김영훈,연병길,오병훈,윤도준,윤진상,이철,정희연,강병조,김광수,김동언,김명정,김상훈,김희철,나철,노승호,민경준,박기창,박두병,백기청,백인호,손봉기,손진욱,양병환,양창국,우행원,이정호,이종범,이홍식,임기영,전태연,정영조,정영철,정인과,정인원,지익성,채정호,한상익,한선호,한진희,서광윤 大韓神經精神醫學會 1998 신경정신의학 Vol.37 No.1

연구목적 : 본 시험의 목적은 임상시험 시작전에 연구자들을 대상으로 PANSS Workshop을 통하여 PANSS, ESRS에 대한 국내에서의 표준화 작업을 구축하고 새로운 정신병 치료제인 리스페리돈의 효과와 안정성을 재확인하여 리스페리돈 사용에 대한 적정화를 이루는데 있다. 연구방법 : 1996년 4월부터 1996년 9월까지 국내 39개 대학병원 정신과에 입원중인 혹은 증상이 악화되어 입원하는 정신분열병 환자 377명을 대상으로 다시설 개방 연구를 시행하였다. 1주일간의 약물 배설기간을 가진후, 리스페리돈을 8주간 투여하였고, 기준점, 1주, 2주, 4주, 그리고 8주후에 평가되었다. 용량은 제1일에는 리스페리돈 1mg씩 1일 2회, 제2일에는 2mg씩 1일 2회, 제3∼7일에는 3mg씩 1일 2회 투여하였다. 이후 환자의 임상상태에 따라 임의로 증량할 수 있으며, 최대 일일 16mg을 초과하지 않도록 하였다. 추체외로 증상을 조절하기 위한 투약을 허용하였다. 임상증상 및 부작용의 평가는 PANSS(Positive and Negative Syndrome Scale), CGI(Clinical Global Impression) 그리고 ESRS(Extrapyramidal Symptom Rating Scale)을 사용하였다. 연구결과 : 377명중 343명(91%)이 8주간의 연구를 완결하였다. 치료 종결시점인 8주후 PANSS 총점수가 20% 이상 호전된 경우를 약물 반응군으로 정의할때, 약물반응군은 81.3%였다. 리스페리돈에 반응하는 예측인자로는 발병연령, 이전의 입원 횟수, 유병기간이 관련 있었다. 리스페리돈은 1주후부터 PANSS양성, 음성, 및 일반정신병리 점수상에 유의한 호전을 보여 효과가 빨랐다. CGI의 경우도 기준점에 비해 1주후부터 유의한 감소를 나타내었다. ESRS의 경우, 파킨슨 평가점수는 기준점과 비교해 투여 1주, 2주, 4주후 유의하게 증가되었다가 8주후 기준점과 차이가 없었다. Dystonia 평가점수는 1주후만 유의한 증가를 보였으며, dyskinesia 평가점수는 유의한 차이가 없었다. 혈압, 맥박수의 생명징후 및 일반 혈액학 검사, 생화학적 검사, 심전도 검사에서 유의한 변화는 없었다. 결 론 : 이상의 다시설 개방 임상 연구를 통해 리스페리돈은 정신분열병 환자에서 양성증상뿐만 아니라 음성증상 및 전반적인 증상에도 효과적인 것으로 사료된다. 보다 명확한 평가를 위해서는 다른 항정신병약물과의 이중맹검 연구가 필요할 것으로 생각되며, 또한 장기적 치료에 대한 평가도 함께 이루어져야 하겠다. Objective : The purpose of this study was to investigate the efficacy and safety of risperidone in the treatment of Korean schizophrenic patients. Method : This multicenter open study included 377 schizophrenic patients drawn from 39 university hospitals. After a wash-out period of 1 week, the schizophrenic patients were treated with risperidone for 8 weeks and evaluated at 5 points ; at baseline, and 1, 2, 4 and 8 weeks of treatment. The dose was increased from 2mg/day(1mg twice daily) to 6mg/day(3mg twice daily) during the first week and adjusted to a maximum of 16mg/day over the next 7 weeks according to the patient's clinical response. Medication to control extrapyramidal symptoms was permitted. The psychiatric and neurological status of the patients was assessed by PANSS, CGI, and ESRS scales. Results : 343(91%) of 377 patients completed the 8-week trial period. Clinical improvement, as defined by a 20% or more reduction in total PANSS score at end point, was shown by 81.3% of patients. The predictors of response to risperidone were associated older age, shorter duration of illness, fewer previous hospitalization. Risperidone had rapid onset of action ; a significant decrease of the total PANSS and three PANSS factor(positive, negative, general), and CGI was already noticed at the end of first week. For the ESRS, parkinsonism rating scores were significantly increased until week 4 comparing with baseline. Dystonia rating scores were significantly increased until week 1, and dyskinesia rating scores were not significantly changed during the study. Laboratory parameters including vital sign, EKG, hematological, and biochemical values showed no significant changes during the trial. Conclusions : This study suggests that risperidone is generally safe and effective against both the positive and negative symptoms in our group of patients.

통풍성 관절염의 임상적 고찰

윤채중,정승문,김영학,김동규,허광식,김태원,배학연,정종훈,이승일,김평남 朝鮮大學校 附設 醫學硏究所 1997 The Medical Journal of Chosun University Vol.22 No.2

통풍은 Purine 대사의 이상으로 발생하는 질환으로, 고뇨산혈증인 사람의 전부가 통풍으로 발현되지 않고 증상의 출현 양상이 다양하여 진단과 치료에 주의가 필요하며, 조기에 적절한 조치를 한다면 충분히 조절이 가능한 질환이다. 본대학 내과학교실에서는 통풍으로 치료한 32명의 환자에서 임상양상, 병력과 검사소견을 분석하여 다음과 같음 결과를 얻었다. 1. 32명 모두 남자이며, 최초 발병 시기는 24세에서 72세로 평균 43.8±11.9세이었으며, 30대에서 40대까지가 19명(59.4%)으로 대부분을 차지하였다. 내원 당시 나이는 27세에서 75세까지로 평균 52.3±10.4세였으며, 내원시 까지 평균 유병기간은 8.5±6.8년으로 나타났다. 2. 동반 질환으로는 고지혈증 12례, 신장질환 10례, 고혈압 12례, 비만 8례, 당뇨 2례 등이었다. 3. 이환된 관절은 단관절 침범이 19례(59.4%), 다관절 침범이 13례 이었으며, 최초 이한된 관절은 족무지 중족골지골 관절로 19례(59.4%)로 가장 많았고, 통풍 결절은 20례(62.5%)에서 관찰되었으며, 유병기간이 10년 이상된 12례중 11례 (91.7%)에서 결절이 관찰되었다. 4. 평균 혈중 요산치는 9.17±1.75 ㎎/dl이었으며, 8.0 ㎎/dl에서 9.9 ㎎/dl 사이가 19명으로 전체의 59.4%를 차지하였다. Objective: The gout is a heterogeneous group of diseases resulting from tissue deposition of monosodium urate or uric acid crystals from extracellular fluids supersaturated with respect to this end product of human purine metabolism. The clinical manifestations are such as hyperuricemia, gouty arthritis, gouty nephropathy, uric acid nephrolithiasis. We analyze of clinical manifestations and associated factors in gout. Method: We have reviewed the medical records, radiologic findings and clinical results of thirty-two patients admitted at our department from April 1996 to July 1997. Result: 1) All patients were male. The mean age at initial attack was 43.8 years old, ranging from 24 to 72 years old. 2) The mean level of serum uric acid was 9.17mg/dl on admission. 3) The first metatarsopharyngeal joint was involved in 19 cases (59.4%). Tophus was observed in 20 cases (62.5%). 4) Hyperuricemia was associated with hypertension, obesity, nephrolithiasis and hyperlipidemia.

일부 산업장 근로자들의 직업성 피부질환 및 천식의 유병조사

윤지석,이영수,조영채,이동배 충남대학교 의과대학 지역사회의학연구소 1990 충남의대잡지 Vol.17 No.2

For the analysis of prevalence of occupational skin diseases and asthma in industrial workers, we studied the 1,274 workers who were engaged in manufacturing workers(direct exposured group to harzardous materials) and clerical workers (indirect exposured group to harzardous materials). The results were as follows: 1. The prevalence rate of occupational skin diseases and asthma in manufacturing workers(36.4%) was significantly higher than that in clerical workers(25.2%) (p<0.005). 2. The prevalence rates of skin diseases(p<0.005) and asthma(p<0.05) in male manufacturing workers were significantly higher than those in clerical workers, and the prevalence rate of asthma(p<0.005) in female manufacturing workers was significantly higher than that in clerical workers. 3. Of asthma in twenties(p<0.005), of skin diseases(p<0.005) and asthma(p<0.05) in thirties, the prevalance rate of manufaturing workers were higher than thoses of clerical workers, however no diffrence was in forties. 4. Of skin diseases(p<0.005) and asthma(p<0.05) in metal plating, of asthma(p<0.005) in cotton spinning, the prevalence rate of manufacturing workers were significantly higher than those of clerical workers. 5. The prevalence rate of skin diseases and asthma in dustness part were significantly higher than those of non-dustness part and poor ventilation part also were significantly higher than good ventilation part (p<0.005). 6. Frequency of involved skin sites, in descending order, were hand(32.1%), leg(24.3%), trunk(20.4%), face(12.1%) and arm(11.1%).

읽기 교육 연구의 방향 : 읽기 교육 연구자의 인식을 바탕으로

윤준채,이천희,김영란 한국초등국어교육학회 2009 한국초등국어교육 Vol.39 No.-

본 연구는 국내의 읽기 교육 분야에서 현재 활발하게 탐구되고 있는 연구 주제와 앞으로 활발하게 탐구되어야 할 연구 주제가 무엇인지를 추출하는 것을 목적으로 한다. 이를 위해, 국내 읽기 연구자를 대상으로 한 설문조사를 통해 자료를 수집하였다. 자료 분석 결과, 국내 읽기 연구자들은 ‘과정 중심 읽기 지도, 읽기 기능과 전략, 읽기 교육과정’과 관련된 주제가 현재 가장 활발하게 연구되고 있다고 반응했다. 현재에 주목을 받고 있지 않은 연구 주제로는 ‘읽기 교사 교육, 균형적인 읽기 지도, 연구 기반 읽기 지도, 교과 독서 지도, 읽기 부진아 지도’ 등을 꼽았으며, ‘교과 독서 지도, 읽기 부진아 지도’ 등을 앞으로 활발하게 연구해야 하는 주제로 인식했다. 마지막으로 분석 결과 및 연구 방법에 대하여 논의하였다. The purpose of this study was to investigate hot research topics for today and tomorrow in the area of reading education. For the study, 21 reading researchers participated in the survey. According to the results, the participants enumerated 'process-based reading instruction, reading skill and strategy, and reading curriculum' as today's hot topics in the area of reading education. As today's not-hot-topics, they picked up 'reading teacher development, balanced reading instruction, research-based reading instruction, and reading instruction for at-risk readers. For tomorrow's should-be-hot topics, they chose 'content area reading and reading instruction for at-risk readers'. Regarding such results, some issues were discussed.

經濟成長의 財政政策에 關한 硏究

尹永彩 全北大學校 商科大學 附設 産業開發硏究所 1976 상과대학論文集 Vol.6 No.-

보강재 길이에 따른 보강토 옹벽의 지진저항 특성 연구

채영수, 윤원섭 水原大學校 2012 論文集 Vol.26 No.-

ABSTRACT In order to understand evaluation of the seismic stability of a reinforced earth retaining, we made chambers of 1:10 (the ratio of the miniature), considering the law of similarity based on drawings of representative cross sections. And we measured an increase in acceleration, earth pressure, and displacement after applying Hachinohe wave(long period), Ofunato wave(short period), and artificial wave, complying with the domestic standards, in order to evaluate the external stability of a reinforced earth retaining wall during earthquake based on the measurements. As a result, a unreinforced earth retaining wall collapsed at 2g of seismic acceleration. But a reinforced earth retaining wall was evaluated to ensure proper stability as well, with respect to the earth pressure gauge, the increments of earth pressure tend to be raised significantly in the upper than the lower and found that the longer reinforcement length, the displacement of reinforcement earth retaining walls was decreased and the earth pressure was increased. 본 연구에서는 보강토 옹벽 구조물의 지진저항 특성을 파악하기 위하여 대표단면을 기초로 하여 축소모형의 비율에 해당하는 상사법칙을 고려하여 1:10의 상사비로 토조를 제작하였다. 그리고 국내 설계기준에 준하여 장주기인 Hachinohe파, 단주기인 Ofunato파, 인공지진파를 가진하여 실험 대상단면에 대해 가속도변화, 토압, 변위를 측정하고, 측정된 결과를 통하여 보강토 옹벽의 지진 시 외적안정성을 평가하였다. 실험결과 보강재를 설치하지 않은 옹벽구조물에서는 지진가속도 0.2g에서 붕괴되었으나 보강재를 설치한 보강토 옹벽에서는 안정성을 확보하는 것으로 평가되었다. 토압계 측정결과 하부보다 상부에서 지진에 의한 토압의 증가량이 크게 발생되었으며, 보강재 길이가 증가할수록 보강토 옹벽의 변위는 저감되고, 토압은 증가되는 결과를 보였다.

建築線 指定으로 발생된 건물 前面空間의 實態調査및 改善方案 : 新村지역을 중심으로

윤채규,주옥자,이상호,박영기 대한건축학회 2003 대한건축학회논문집 Vol.19 No.1

When new buildings are constructed at streetside, buildingline must be retreated by building regulations for improving street environment, consequently front spaces of building appear irregularly. This study presents a desirable improvement method in terms of design and institution regarding this space to make urban environment comfortable and rational.

일부 도시지역 주민들의 비만도와 관상동맥질환 위험인자와의 관련성

이영선,윤석화,조영채 충남대학교 의과대학 의학연구소 2002 충남의대잡지 Vol.29 No.2

The present study was intended to reveal the relationships between the severity of obesity and various risk factors for coronary heart disease. The studs subjects were 1.838 urban inhabitants (male: 962. female: 876) who went through a general health check-up during the period between January through December. 2001. The degree of obesity was estimated by BMI and its relation to coronary heart disease risk factors were investigated. With respect to the severity of obesity. the mean systolic and diastolic blood pressure. TC. LDL-C. TG and AI increased significantly. but HDL-C showed a reversed pattern. with a higher severity. On the other hand. no difference was found in FBS. The severity of obesity was directly correlated with SBP. DBP. TC. LDL-C. TG and AI. Multivariate logistic regression analysis showed that the risk factors relevant to the severity of obesity were sex. DBP and TG. The odds ratio was 2.3 times higher in women than in men. and DBP and TG were 3.8 and 1.8 times higher in the obesity group than in the normal weight group. respectively. In conclusion. blood pressure. TC. LDL-C. TG. and AI significantly increase. and HDL-C decreases in proportion to the severity of obesity. The maintenance of desirable body weight should be a target for intervention with the idea of coronary heart disease prevention.

담체의 표면거칠기와 전단응력이 미생물 부착에 미치는 영향

박영식,송승구,이채남,최윤찬 부산대학교 환경문제연구소 1995 環境硏究報 Vol.13 No.-

The propose of this paper was to examine the effect of surface roughness and shear stress of support medium on the development of biofilm in a rotating biological contactor. The surface roughness of PMMA as a support media was adjusted to 0.4, 0.8, 1.2, and 3㎛, respectively. Shear stress was varied with speed of rotating biological contactor. At low shear stress, bacterial attachment was not varied greatly with surface roughness. But at increased shear stress, bacterial attachment was changed sharply with surface roughness.