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.

흰쥐 시상에서 Epidermal growth factor receptor면역반응 신경세포의 생후 발달에 관한 연구

박영란,정윤영,김종중,문정석,오재욱,정영욱,김주수 조선대학교 2003 The Medical Journal of Chosun University Vol.28 No.1

Background and Objectives : Epidermal growth factor receptor (EGFR), a 170-kDa transmembrane glycoprotein, appears to mediate epidermal growth factor (EGF) activity. Transforming growth factor-α and EGF produce their biological effects in numerous systems by stimulating the EGFR In this study, we examine the postnatal development of EGFR immunoreactivity in the different regions of the thalamus of the rat Materials and Methods : The present study is based on 28 postnatal cases of rat thalamus ranging from the day of birth, postnatal day 0 (P0) to 30 days (P3, P5, P10, P15, P20, P30), and these cases were compared with adult rat thalamus. Cryostat sections were processed free-floating with monoclonal antibody by immunohistochemistry Results : EGFR immunoreactivity in the thalamus of the rat showed very different patterns according to postnatal ages and thalamic areas. EGFR-immunoreactive cells appeared in the first two postnatal weeks, except the ventral posterior thalamic nuclei. In the early postnatal days, EGFR-immunoreactive cells appeared thalamic midline structures, increased progressively in the first two postnatal weeks, and followed mediolateral gradient. The mature patterns of EGFR-immunoreactive cells were achieved at P20 Conclusion : These data indicate that the maturation of EGFR-immunoreactive cells requires a relatively prolonged period of time to achieve an adult configuration. Many growth factors probably play protective or neurotrophic roles at EGFR-immunoreactive neurons of thalamus both young and adult rats In addition to difference in time of appearance in thalamic nuclei and developing pattern with mediolateral gradient suggest that EGFR-immunoreactivities are correlated with the appearance of the related functional.

노인에서 내피의존성 혈관반응에 대한 비타민 C의 효과에 대한 연구

온영근,김용석,오도연,최진호,황의석,김철호 대한노인병학회 2001 Annals of geriatric medicine and research Vol.5 No.1

Brassica 種들의 花뢰크기에 의한 小胞子 發育段階 및 胚發生 比較

장영석(Young Seok Jang),민경수(Kyung Soo Min),오용비(Yong Bee Oh),정동희(Dong Hee Chung) 한국육종학회 1997 한국육종학회지 Vol.29 No.4

The purpose of this study is to search for the identifing method that could separate buds with embryogenic potential from collected buds for increasing the efficiency of embryogenesis by microspore culture in Brassica species. It was investigated developmental stage of microspore by bud-size and ratio of petal/anther length and compared to amount of embryogenesis through isolated microspore culture from the buds with late-uninucleate stage. In Brasica napus, Lisandra of spring type showed bud-size of 3.2~4.1mm which belongs to late-uninucleate stage as embryogenic microspores and their range of petal/ anther length ratio were 1/2~3/4. Hallayuchae of winter type rapeseed showed bud-size of 3.1~3.6mm which belongs to late-uninucleate stage as embryogenic microspores and their range of petal/anther length ratio were 1/3~1/2. Two genotypes of B juncea had the same petal/anther length ratio as range of 1/2~3/4 with embryogenic microspores but their bud-size were some difference as bud-size of Young-sanpohwanggyeja were 2.9~4.0mm and bud-size of Hwanggyeja were 2.9~4.1mm. Also, two genotypes of B. campestris had the same petal/anther length ratio as range of 2/3~3/4 with embryogenic microspores but bud-sizes were some difference as bud-size of Hyakusai were 2.9~3.4mm and bud-size of Sosongchae were 2.9~3.2mm. In B. oleracea, the petal/anther length ratio with embryogenic microspores according to bud-size were showed range of 1/2~2/3 in all of two genotypes and bud-size of Broccoli were 2.4~3.2mm and bud-size of Cauliflower were 2.9~3.7mm. In the embryo yield per 100,000 microspores by isolated microspore culture from the buds with embryogenic microspores, Young-sanpohwanggyeja of B. juncea were 47 embryos and Hwanggyeja of B. juncea were 23 embryos, B. campestris of Hyakusai were 367 and Sosongchae were 123, B. oleracea of Broccoli were 678 and Cauliflower were 562. However in B. napus was showed much differences by the growth habit, the spring type of Lisandra were producted 7,047 embryos of which higher about 9.2 times than those of winter type Hallayuchae.

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.

섬유 보강 모래의 전단 강도 특성

吳英錫,朴鎔遠 명지대학교 공학기술연구소 1992 공학기술연구소 논문집 Vol.7 No.-

In this study, we have studied the shear strength and stress-strain characteristics of fiber reinforced sand through laboratory direct shear test. Among many factors affecting the reinforcing effect the stiffness, the interval and orientation of the nclusions are lighted in this study. In the tests, KS standard sand and poly-vinyl wire coating are used and the number of reinforcement and inclination angle to the expected shear plane are changed. From the test results, it is found that fiber reinforced sand has greater shear resistance and extensibility(ductility) as well and smaller loss of post peak strength compared to unreinforced sand. It is also observed that the initial orientation of the reinforcement affects the magnitude of the shear resistance increase in the composite. In this test, reinforcements oriented at 45˚ to shear plane produced the maximum increase in shear resistance. Further research and observations on full scale structures are required in order to develop a better understanding of the potential effect of reinforcement bending stiffness and on the behavior of fiber reinforced sand.

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.

조직 확장기를 이용한 안면부 재건

오 경,정영하,김정태,김석권 대한미용성형외과학회 1997 Archives of Aesthetic Plastic Surgery Vol.3 No.1

In the past years skin grafts, local flaps and free flaps have been used in reconstructing skin or sift tissue defects and deformities of the face where primary closure is not feasible. A number of local flaps have been used for reconstruction of facial defects and deformities, but the size of a defect that could be treated in such a way was restricted and the donor site deformity was another problem of local flaps. Introduction of the tissue expansion technique has made it possible to cover even wider defects with neighboring skin and advantageous in facial reconstruction in that such defects can be resurfaced with skin of similar color, texture and thickness, a match superior to that of skin obtained elsewhere. We used tissue expanders in reconstructing defects and deformities of the face(post-burn scar ; 17cases, post-traumatic scar ; 7cases, congenital nevus ; 3cases, total 27cases) from Mar. 1990 to Sep. 1996. We used or croissant type tissue expander for the reconstruction of small-sized scar on medial cheek and to use rectangular type expander for large-sized scar on lateral cheek. Ports are placed under the scar or scalp. Expansion period ranged from 28days to 97days (mean 7weeks) and overinflation (mean 170%) was done. And Various methods are used for prevention of complication. We have made anchoring sutures of the remained capsule to the underlying periosteum for prevention of ectropion. We have got satisfactory results from that aesthetically and functionally, so report the results with a review of the current literature.

동일한 혈관 내에 발생한 이식형 약제 주입기 카테터의 위치이상

오대석,김영재,김명훈,조광래,임세훈,이정한,이근무,정순호,신치만 仁濟大學校 白病院 2010 仁濟醫學 Vol.31 No.-

저자들은 56세 여성 환자의 왼쪽 쇄골 하 정맥에 시행한 이식형 약제주입기 카테터의 삽입 후 발생한 비정상 위치에 대한 증례를 보고하고자 한다. 카테터의 끝은 환자의 늘 어진 가슴, 체위, 신체의 움직임, 카테터의 유동성 등의 영향으로 천자된 정맥 내에서 견인되고 뒤쪽으로 이동하였다. 환자는 어떠한 증상도 호소하지 않았지만 비정상 위치의 카테터는 심각한 합병증을 유발할 수 있기 때문에 제거되었다. 따라서 시술자는 약제주입기 삽입 전에 환자의 신체 상태와 단순 흉부 촬영상을 확인하고 카테터의 비정상 위치가 발생할 수 있는 위험 징후를 알아차려야 하겠다.

地方政府의 環境行政機能 强化方案

오영석 동국대학교 경주대학 1995 東國論集 Vol.14 No.-

The full-scale autonomy of local governments in Korea in 1995 is considered as a chance to raise the capability of environmental administration of local governments for several reasons. This article aims to discuss four menas to increase the capability. The current system of environmental administration in Korea is described in terms of organizations and functions. The Korean system is highly centralized. The Korean Environmental Protection Agency and other related ministries possess almost all powers in planning and enforcement. It is recommended to turn over the centralized powers to local governments. Some criteria are suggested for the distribution between central and local governments. It includes efficiency, spill-over effect, technology, and level of hazard. The four means to raise the administrative ability of local governments are (1) to hire more public servants who have skills and knowledge in environmental managements, (2) to expand expenditures for environmental protection, (3) to adjust current environmental administration functions between central and local governments, and (4) to transfer some public functions to individuals and firms in private sectors.