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.

간세포암과 감별이 어려웠던 악성중피종 치험 1예

김선문,허원석,채경훈,강윤세,정재훈,김연수,박기오,문희석,이엄석,김석현,성재규,이병석,이헌영,신경숙,조준식,송인상,강대영 충남대학교 의학연구소 2003 충남의대잡지 Vol.30 No.2

Malignant peritoneal mesothelioma is a rare neoplasm that arises from the mesothelium of a serosal cavity and is a rapidly fatal disease with a median survival of 4 to 12 months for untreated cases. Recently, we experienced a case with malignant peritoneal mesothelioma who was suspected hepatocelluar carcioma by abdominal CT scan and was confirmed by biopsy including immunohistochemical stain(calretinin) after surgery. We performed tumor excisions and wedge resection of the liver(segment Ⅷ)and inserted Tencoff catheter in abdominal cavity at 25th day of post-operation. We treated with intraperitoneal paclitaxel(25mg/m^(2)/day for 5 days) six courses monthly. She was well tolerable and is still living without any evidence of recurrence for 14th month of post-operation.

Neuropathic Pain의 동물모델에서 유발된 Thermal Hyperalgesia에 대한 Clonidine의 효과

윤석화,오세철,최세진 충남대학교 의과대학 지역사회의학연구소 1993 충남의대잡지 Vol.20 No.2

The effects of intraperitoneal injection(i.p.) of the alpha 2 adrenal receptive agonist, clonidine on the thermal hyperalgesia produced by unilateral patially tight ligation of the sciatic nerve was studied in rats. First in the preoperative and postoperative Mays, paw withdrawal latency of both hind paw(lesioned,unlesioned) with heat stimulant was tested. After that, each groups of rats injected saline, clonidine 10㎍/kg, or clonidine 50㎍/kg. I.p.10㎍/kg and 50㎍/kg clonidine, paw withdrawal latency of lesioned side significantly reduced than saline group. It is suggested systemical clonidine may be useful in treating neuropathic pain in humans.

하악골 골절 환자에 있어 수술후 합병증으로 발생한 골수염의 치험례

윤규호,전인성,신용길,박준호,허남오,방석준 大韓顎顔面成形再建外科學會 1996 Maxillofacial Plastic Reconstructive Surgery Vol.18 No.4

The term osteomyelitis literally means inflammation of bone marrow. It is described as an inflammatory condition of bone primarily engaging the medullary Following circulatory collapse and ischemia, the involved portions of the bone become necrotic. Cellulitis and osteomyelitis are the most frequent complications of fractures of the mandible and maxilla, because there is an abscessed tooth in the line of fracture. Since most fractures are compound fractures, infection may develop because of contact with oral secretions or outside air. The treatment of chronic osteomyelitis is still under debate. Some authors rely on antibiotics alone, while others advocate combination with surgery. But when infection occurs, establish proper drainage and administer antibiotics. Author treated a case of infected mandibular fracture with mandibular osteotomy, sequestrectomy, iliac bone graft and hyperbaric oxygen therapy, who had suffered suppurative osteomyelitis and mandibular nonunion following the open reduction of the mandibular fracture.

HPLC-MS/MS를 이용하여 혈장 중 레보티인정의 정량분석

채석,오형근,이상선,김형기,손동렬,염윤기,맹주양,권준택 순천향의학연구소 2008 Journal of Soonchunhyang Medical Science Vol.14 No.2

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해조류에서 추출한 SCH-T3의 elastase 억제

오경석,박영립,이종석,황규왕,염윤기 순천향의학연구소 2001 Journal of Soonchunhyang Medical Science Vol.7 No.1

Background & Objective: Upon UV irradiation of skin, matrix metalloproteinases are induced and then degrade collagen and elastin which provide the structural integrity of skin. The purpose of this study is to investigate the inhibition of elastase by SCH-T3 extracted from marine plants. Method: From gathered seaweeds, which are Laminariacea and Alariaceae in Phaeophyta, In Korea water, 21 materials were extracted. To determine the optimal condition for the extraction of SCH-T3, the yields of SCH-T3 was measured compared at various solvents, concentrations, and extraction time. Finally, the inhibitory effect of SCH-T3 on elastase was measured under various conentrations of SCH-T3. Results: Among 21 extracts, SCH-T3 had excellent elastase inhibitory effect. The yields of SCH-T3 was highest with the use of 60% and 70% ethanol as sovents, at 12 hours extraction, and with increasing temperature. Conclusion: These results suggest that SCH-T3, extracted from marine plants, has an inhibitory effect on elastase in vitro and may be used in prevention and treatment of photoaging in the future.

서울 지역 여자대학교 집단에서 월경전기 증후군 및 월경전 불쾌기분장애의 유병율

정범석,이철,이지현,서민경,한오수,김창윤 大韓神經精神醫學會 2001 신경정신의학 Vol.40 No.4

연구목적 : 가임기 여성의 75%가 하나 이상의 월경전기 증상을 경험하며, 일상생활에 지장을 주는 경우도 3∼8%에 이르지만 한국 여성을 대상으로 한 월경전기 증후군(Premenstrual syndrome : PMS)및 월경전 불쾌기분장애((Premenstrual dysphoric disorder : PMDD)에 대한 역학 조사는 부족한 실정이다. 따라서 본 자들은 한국에서의 유병율, 증상의 양태 및 삶에 미치는 정도 등의 역학 조사를 통해 월경전 불쾌기분장애에 대한 올바른 정보를 제공하고 관련 임상 연구의 기초자료로 활용하고자 본 연구르 시행하였다. 방 법 : 6개의 서울 소재 4년제 여자대학교에서 무작위 군집표본 추출로 선택된 4개 학교의1∼3학년 학생 중 무작위 군집표본추출을 통해 선택된 1419명을 대상으로 하였다. DSM-IV진단기준을 근거로 저자들이 제작한 6점 척도의 설문지가 사용되었으며, 난포기에 비해 황체기에 75%이상 악화된 경우 증상이 있다고 판정할 경우의 월경전 불쾌기분장애의 유병율을 조사하였다. 월경전 불쾌기분장애 집단과 증상은 있으나 진단기준에 부합되지 않는 월경전기 증후군 집단으로 나누어 증상 양태, 식습관 변화, 생활에 미치는 영향 정도 등을 비교하였다. 결 과 : 부적절한 자료 198명(13.9%), 주요 신체 혹은 정신질환을 앓은 경우 등 선정 배제 기준에 속하는 경우 348명(24.5%)을 제외한 873명이 최종 분석되었다. 873명 중 월경전 불쾌기분장애의 유병율은 5.0%이었으며, 월경전기 증후군의 유병율은 83.3%이었다. 가장 흔한 증상은 월경전기 증후군 집단의 경우 신체증상(54.6%)이었고, 월경전 불쾌기분장애 집단의 경우 '지속적으로 짜증난다'(95.5%)이었다. 월경전 불쾌기분장애 집단의 88.6%에서 증상 때문에 한 달에 1∼2회 이상 일이나 공부에 지장이 초래되었다. 결 론 : 한국 여자대학생 집단이 경험하는 월경전 불쾌기분장애의 유병율과 증상 양상은 외국과 비슷하다. 아울러 월경전 불쾌기분장애 집단은 월경전기 증후군 집단에 비해 기분 증상이 더 흔하고 심하는 점에서 월경전 불쾌기분장애는 월경전기 증후권과 구별되는 하나의 질환 상태임을 시사한다. Objects : More than 75% of women have been reported to experience premenstrual symptoms and three to eight percent of them suffer from premenstrual dysphoric disorder(PMDD). But little is known about prevalence of premenstrual syndrome(PMS) and PMDD and PMS in Korean women who sttended universities at the time of survey. Methods : One thousand four hundred and nineteen subjects were randomly selected with cluster sampling methods among four women's university in Seoul. We measured the severity of premenstrual symptoms using six-point rating scale developed by the authors on the basis of the research criteria for PMDD in DSM-IV. Premenstrual worsening of symptoms was defined as increase in symptom scores of more than 75% from follicular to luteal phase score. And also, we compared characteristic symptoms, eating behaviors, and functional impairments between PMS and PMDD. Results : After excluding inadequate data according to our exclusion criteria, 873 of 1419 subjects(61.5%) were included in the estimation of the prevalence of PMS and PMDD. Each prevalence rate of PMS and PMDD was found to be 83.3% and 5.0% on the basis of 75% change method respectively. The most frequent symptom was physical symptoms such as headache or breast tenderness(56.4%) in PMS and 'felt irritable'(9.5%) in PMDD. Of the 44 subjects with PMDD, 39(88.6%) reported to have experienced the impairment in work or school at least once per month because of premenstrual symptoms. Conclusions : Our results indicate that prevalence and symptoms of PMDD in Korean university women are similar to those in western culture. The finding that mood symptoms were more frequent and severe in PMDD than in PMS implies that the former may be a disordered condition to be distinguished from the latter physiologic one.

핸드스프링 몸펴 앞공중1회 비틀기 동작의 소요시간 및 각운동량 분석

권오석,윤양진,서국웅 한국운동역학회 2002 한국운동역학회지 Vol.12 No.2

남자 기계체조 국가대표 선수 3명과 대학선수 3명을 대상으로 핸드스프링 몸펴 앞공중1회 비틀기 동작을 구간 및 국면별로 분석하고 동작의 숙련도에 따라 역학적 변인이 집단 간 어떠한 차이를 보이는지를 구명하기 위하여 Kwon3D 프로그램을 활용하여 분석한 결과 다음과 같은 결론을 얻었다. 시간요인에서 보폭을 크게 딛는 것이 손을 빠르게 지지 할 수 있고, 핸드스프링 체공시간은 짧게 하여야 발구르기의 압력을 높여 비틀기동작에서 체공 소요 시간이 길어지므로 비틀기 수행의 완성도를 높일 수 있는 것으로 나타났다. 각운동량 요인에서 기술수행 시 전체적으로 좌우(X)축에 대한 각운동량이 전후(Y)축과 수직(Z)축에 대한 각운동량에 비해 더 큰 값을 보였다. 좌우 축 각운동량은 지면에서 이지되어 동작을 수행하는 핸드스프링회전과 앞공중1회 비틀기에서 숙련자가 상대적으로 더 큰 각운동량 보이는 것으로 나타났다. The purpose of this study were a two-fold: ⑴ to analyze event and phase of handspring salto forward stretched with turn; ⑵ to know the differences in the kinematic variables between two groups. A Kwon3D program served for the estimation of this study. The group was divided into three National representative and three well-trained calisthenics in this study. The results of this study revealed that ⑴ the forward somersault performance was increased when duration time in the air was long during the salto forward stretched that the duration time of Handspring is short, the pressure at takeoff is high, the stride is large, and hands are supporting on the ground quickly; ⑵ comparing the angular movement of anterior and posterior y axis and vertical z axis, the angular movement of right and left x axis was higher during the performance. As a result, the national representative players showed better performance in Handspring salto forward stretched with turn.

매트운동에서 핸드스프링 앞수완동작의 운동학적분석

권오석,윤양진 釜山大學校 附設 體育科學硏究所 2002 體育科學硏究所 論文集 Vol.18 No.1

In this study, 4 gymnasts who were students of B University at the same time was taken and their performance of forward Handspring salto with body stretched was looked at through 3 dimensional of the body, the tract of moving and its kinematic element. It is all to provide basis data for efficient training of gymnasts and the findings are as follows: 1. From the examination of the sequence of duration phase, it appeared that in phase 1, the superior group had longer duration with long strider in home step, in phase 2, they bent their upper body making big shoulder angle and changed the straight-line motion to circular motion. And it appeared to result in efficient circular motion while in flight phase of 4 and 5. 2. It appeared that in the event 2 in which the movement of support with hands took place, the Superior group had bigger shoulder angle so that the Handspring movement was faster in its rotation on the axis of hands supporting. In event 3 of jump in feet, the hips angle was big enough to produce with its weight sufficient pressure on feet to maximize the reaction of the floor. 3. For the speed in each phase, the Superior group spurred rapid speed with the hips angle curved a little bit in event 4 in which the body made vertical angle to the floor while in handspring salto forward piked movement of the body and in event 5, the hips angle extended rapidly producing good rotation speed. In summery of all the elements considered above, big strider with the body bent to produce decisive support on the hands seemed to result in increased rotation speed in handspring, bigger pressure on feet, and good speed in handspring salto forward stretched.

핸드스프링 무릎굽혀 앞공중돌기동작과 몸펴 앞공중돌기동작의 운동학적 비교분석

권오석,윤양진 부산대학교 사범대학 2002 교사교육연구 Vol.41 No.-

In this study, 4 gymnasts who were students of B University at that time were taken and their performance of handspring salto forward tucked and handspring salto forward stretched at through 3 dimensional movement analysis to tell the duration for each phase of the movement, the movement of the articulation of the body, the tract of moving center of the body, and its kinematic element. It is all to provide basic data for efficient training of gymnasts and the findings are as follows: 1. The time duration for phase 1 and 2 differed each other and faster landing on hands in forward handspring salto forward stretched than in forward salto with the body bent helped the straight-line movement change to circular movement giving the handspring a big circular movement, and forward jumping on feet with rapid upright of the upper body maximized the circular radius on the axis of the jaw, contributing to rapid backward circular movement of the lower part of the body. 2. In the observation of the position of the body center, the sway of the body center and the power dispersion was smaller in general in forward salto with the body stretched than in forward salto with the body bent. And in its forward and backward position, it showed lower position in handspring phase of 1 and 2, but higher in the salto of phase 3, 4 and all these contributed to bigger and more stable circular motion. 3. Articulation angle of the body in each phase of handspring forward salto with the body bent and in forward salto with the body stretched appeared to be different through 5 phases. It had more centripetal force in forward salto with the Elbows, shoulders, hips, knees having more curve. In forward salto with the body stretched, centrifugal force appeared to be strong with the elbows, shoulders, hips, knees all being extended. To summarize, Handspring forward salto with the body bent seems to have curved articulation and be slow, while in forward salto with the body stretched, its circular movement appeared be faster with speedy landing on hands, extended knees angle for good jump, and with accelerated hips articulation. Handspring forward salto with the body stretched appeared to enhance its technical performance with far-reaching circular motion. Therefore, forward salto with the body stretched is considered to produce more gracious and dynamic motion than forward salto with the body bent does.