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.

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

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.

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.

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.

Gibberellin 處理가 파인애플 果實肥大에 미치는 影響

吳現道,吳迎碩 濟州大學校 亞熱帶農業硏究所 1994 亞熱帶農業硏究 Vol.11 No.-

Pineapple은 施設栽培時 生長調節劑 Gibberellin의 效果를 究明하기 위하여 1992年 7月 3日에 Gibberellin (25, 50, 100, 200, 400ppm)을 처리하였을 경우 파인애플 과실비대에 미치는 효과를 요약하면 다음과 같다. 1. 葉長, 葉數, 抽苔期, 成熟期는 處理間에 有意性이 없었다. 2. 冠芽크기, 果梗長, 果徑, 果重은 處理間에 有意性이 認定되었다. 3. 果重에 있어서는 無處理區에 비해 25, 50, 100, 200ppm까지는 濃度가 높아짐에 따라 果重이 增加하였으나 400ppm 處理區에서는 200ppm 處理區보다 減少하여 200ppm 處理區에서 가장 良好한 結果를 보였다. 4. 果長과 葉長間에는 正의 相關關係를 보였고, 果重과 果徑間에는 高度의 相關關係가 認定되었으나 기타 형질에 있어서는 相關程度가 낮은 편이었다. This experiment was carried out in order to investigate the effects of gibberellin (25, 50, 100, 200, 400 ppm) treatment on growth of furit in Pineapple. Gibberellin was applied on july 3, 1992 to fruit 1. There were not significant differences among treatments for the length of leaves, number of leaves per plant, days to inflorescences emergence and days to maturity. 2. There were significant differences among treatments for crown size, peduncle length, furit diameter and fruit weigtht. 3. Fruit weigth increaseed as the concentration of gibberellin increased form 0 to 200ppm and decreased at 400ppm compared to 200ppm. 4. Fruit length was positively correlated with length of leaves and fruit weight was positively correlated with fruit diameter. However, there were no significant correlated among the other characters.

장거리달리기 생활체육 동호인의 10㎞ 달리기 구간기록과 체중의 관계에 대한 사례연구

오봉석,조영제 한국스포츠리서치 2003 한국 스포츠 리서치 Vol.14 No.6

This case study was carried out to elucidate whether body weight was affected by long distance run and to explore the relation body weight with the 10㎞ section records and to provide the prevention method of overweight and obesity and the elevation method of 10㎞ record to a lot of people interested in long distance run. The subject was thirty-nine years old male who has been taking part in 10㎞ run (1time/week) regularly for 6 months. And the section records of 10㎞ run were measured on 4㎞, 7㎞, 10㎞. The results were as followed: First, the body weight was significantly decreased after 10㎞ run, and the mean reduction extent was 1.02㎏. After six-month 10㎞ run(1time/week) the body weight was decreased about 3.39㎏(p<.001). Second, the relation of body weight with 10㎞ section records was significant(p<.01). Third, after six-month 10㎞ run(1time/week) the section records of 10㎞ were significantly shortened 1 minute 40 seconds in 4km, 2 minutes 10 seconds in 7㎞, 4 minutes 20 seconds in 10㎞(p<.001). Fourth, after 3 months of 10㎞ run(1time/week) the section record change modes of 10㎞ were continual. In summery, body weight was significantly reduced by 10㎞ run and has significant effect on the section records of 10㎞ run. And the accommodation period to 10㎞ run was about 3 months, so a person who interested in long distance run should put the first 3 months of long distance run to practical usage as an accommodation period and during this period he must more concentrate on running long distance than on shortening record.

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.

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.