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.

조혈모세포이식술이 골수기질세포의 기원 및 조골세포로의 증식 및 분화에 미치는 효과

강무일,조성원,오은숙,백기현,이원영,오기원,김혜수,한제호,윤건호,차봉연,이광우,손호영,강성구,김춘추 대한내분비학회 2000 Endocrinology and metabolism Vol.15 No.4·5

유성견에서 교정적 치아이동에 따른 치주조직 변화에 관한 연구

강남용,윤영주,김광원 대한치과교정학회 1997 대한치과교정학회지 Vol.27 No.4

교정력에 의한 치주조직의 변화를 알아보기 위해 성장중인 유성견에서 단기간의 교정력이 가해진 직후와 보정기간 동안 일어나는 치아와 골조직의 변화양상을 조직학적으로 관찰하였다. 본 연구에서는 생후 4-6개월된 유성견 3마리를 이용하여, 각 실험동물의 하악 좌측 견치와 제1대구치는 실험군으로, 우측 견치와 제1대구치는 대조군으로 하였다. 하악견치와 제1대구치에 치관사이에서 최초 교정력이 200mg이 되도록 0.018"X0.022" S.S closed coil spring(Dentarum Co)의 길이를 조절하여 치아에 결찰시키고 장치는 1주간 활성화기간을 갖는 후 14일, 28일의 보정기간을 거쳐 희생시켜 하악골을 절제하여 통법에 따라 H-E염색군, 연마표본군, ALP염색군, TRAP염색군등으로 나누어 염색을 시행하여 다음과 같은 결과를 얻었다. 1. 교정력을 종료한 직후 견인측 치주인대 폭경이 대조군보다 더 증가된 상을 보이고, 반대로 압박측은 폭경이 감소된 소견을 보이며 치주인대의 섬유들이 치축에 수직으로 압축되며 초자양 변성이 관찰되었다. 대조군에서 관찰되는 다수의 규칙적인 배열을 보였던 조골세포가 견인측에서는 간혹 관찰되었다. 2. 교정력 종료후 14일 보정기간 경과군 치주인대내 섬유아세포들이 증식되어 초자지질대가 회복되는 소견이 관찰되었고 견인측 치주인대의 폭경이 교정력을 종료한 직후군보다 감소하였으며, 소수의 ALP(+) 조골세포와 함께 신생골형성도 관찰되었다. 압박측 치주인대의 폭경은 교정력을 종료한 직후군보다 다소 증가하였으며 골흡수도 증가되었다. 3. 교정력 종료후 28일 보정기간 경과군 치주인대섬유는 정상적으로 회복되어 대조군과 유사한 양상을 보였고 견인측 치조골내 다수의 ALP(+)조골세포와 활발한 신생골형성이 관찰됨과 더불어 압박측 치조골은 다수의 TRAP(+)파골세포와 왕성한 골흡수양상을 보였다. 이상의 결과를 종합해 볼때 교정력을 7일간 가한 직후 유리질화가 관찰되었고 교정력을 종료후 28일 보정기간 경과군에서 압박측에서는 파골세포 견인측에서는 조골세포의 활성과 함께 각각에서 왕성한 골 흡수와 신생골형성이 관찰됨을 알 수 있다. For orthodontic tooth movement, optimal orthodontic force should be maintained without periodontal breakdown and alveolar bone should be remodeled physiologically. Therefore, To obtain proper occlusion through tooth movement within alveolar bone, we should know the biomechanics of teeth and supporting tissues. The present study was performed to observe histologic changes of periodontal tissue immediately after application of orthodontic force and during the retention period in growing young adult dogs. In this study, of same animal. The 0.18"X0.22" stainless steel closed coil spring(Dentaurum Co.) was ligated on the experimental teeth at initial 200gm-force from mandibular canine to 1st molar. The animals(4 to 6 months aged young adult dogs)were sacrificed on 0, 14, 28 days after the finish of appliance activation, and the tissue samples were divided into himatoxylin-eosin(HE) staining section, groud section, alkaline phosphatase(ALP) staining section, and tartrate-resistant acid phosphatase(TRAP) staining section. Thereafter, the proparations were examined under light microscopy. The following results were obtained: 1. Immediately after the finish of appliance activation, the periodontal space was increased in tension side, but decreased in pressure side compared to that of control. The hyalinized zone was also observed in the periodontium. 2. After the 14-day retention, peridontal space was decreased in tension side ans slightly increased in pressure side compared to that of immediately after the finish of appliance activation. The hyalinized zone was repaired and a few osteoblasts showing slightly new bone formation were seen. Osteoblasts were scarcely observed along the alveolar bone. 3. After the 28-day retention, peridontal fibers are normally repaired. A lot of TRAP(+) osteoclasts and increased alveolar bone resorption were observed in pressure side, and AP(+) osteoblast and increased new bone formation were observed in tension side.

Investigation of the April 2000 forest fire damage in Kang-won Province, Korea, using RADARSAT data

Kang, Sung Chul,Seo, Jin Won,Lee, Tae Hee,Park, Sang Eun,Hong, Suk Young,Moon, Wooil M. 대한원격탐사학회 2000 International Symposium on Remote Sensing Vol.16 No.1

The series of forest Fires in Kangwon Province in April, 2000, were one of the mast serious ones in the Kang-won Province in recent years. The fire damaged areas are extensive and this paper investigates the utility of the satellite image data, particularly the RADARSAT SAR data. One of the main objectives of this study included evaluation of potential usefulness of the C-band RADARSAT data in the detection of forest fires in mountainous areas. Among several fire damaged sites, the area near Samchuk (city) was selected as the main study area and mufti-temporal RADARSAT(raw) data were acquired and the processed results were comparatively investigated with the IRS-1c data acquired shortly after the fire. To identify the burnt area from the undamaged background in the optical imagery, supervised classification and NDVI processing were carried out and tested with the IRS-1C data. For this experiment, several sets of raw RADARSAT standard and Fine mode (S4, F3, ascending orbit) data were processed and the final image was formed. In addition to the final image, sigma nought (σ°) was catnputed and compared for the burnt area against the undamaged areas. Because of the steep slopes in the study area and subsequent deviation from the flat surface scattering models, the fire scars in the sigma nought (σ°) image were not apparent. However, fire scars are slightly detected in the difference and ratio images obtained from the signal intensity data acquired at different dates (bath before and after fire). Texture analysis of the image data including the burnt areas were carried out using the Multiplicative Markov Random-Field (MMRF) algorithm. The detection of the fire damaged area from both standard mode and fine mode RADARSAT was not as straightforward as in optical data. However, Previous studies with ERS-1 S_AR and RADARSAT data in Indonesia and in the North American Plains indicate that C-band SAR data provide us with an effective tool for studying the forest fire damages. However, the application of C-band SAR data to the analysis of the forest fire areas requires careful processing of the data with realistic scattering models.

Organic Complementary Circuits: Remarkable Enhancement of Hole Transport in Top‐Gated N‐Type Polymer Field‐Effect Transistors by a High‐k Dielectric for Ambipolar Electronic Circuits (Adv. Mater. 40/2012)

Baeg, Kang‐,Jun,Khim, Dongyoon,Jung, Soon‐,Won,Kang, Minji,You, In‐,Kyu,Kim, Dong‐,Yu,Facchetti, Antonio,Noh, Yong‐,Young WILEY‐VCH Verlag 2012 Advanced Materials Vol.24 No.40

<P>On page 5433, Yong‐Young Noh, Antonio Facchetti, Kang‐Jun Baeg, and co‐workers report that high performance ambipolar complementary inverters and ring oscillators are provided by a remarkable enhancement of both hole injection and transport for n‐channel dominant N2200 OFETs. The significant enhancement of hole mobility in N2200 OTFTs is attributed to the strong dipoles in fluorinated high‐k gate dielectric blend of P(VDF‐TrFE):PMMA. </P>

골수이식 후 골밀도 및 골대사의 변화 : 2년 추적관찰 2-Year Prospective Study

이원영,강무일,오은숙,오기원,한제호,손현식,윤건호,차봉연,이광우,손호영,강성구,신완식,민우성,김춘추 대한내분비학회 2000 Endocrinology and metabolism Vol.15 No.4·5

Multiple myeloma 환자에서 Bortezomib치료 후 발생한 마비성 장폐색증 1례

김준영,이원식,손창학,박성길,진한영,박석주,조영완,정은욱,강명주,박정하,주영돈 인제대학교 2006 仁濟醫學 Vol.27 No.-

Bortezomib is the first clinically available proteasome inhibitor that is clinically effective in the treatment of multiple myeloma. A proteasome inhibitor acts through multiple mechanisms to arrest tumor growth, tumor spread, and angiogenesis. The main adverse effects of bortezomib are gastrointestinal symptoms, cytopenia, fatigue, and peripheral neuropathy. To date, severe paralytic ileus has not been reported as a toxic effect of bortezomib treatment in multiple myeloma. Bortezomib is a novel agent that has only been used clinically for 30 months, so a need exists to further evaluate its toxicity. We report a case of grade Ⅲ (NCI CTCAE v3.0) or grade Ⅳ(SWOG toxicity criteria) paralytic ileus in a 65-year-old man with relapsed multiple myeloma who underwent one cycle of single-agent bortezomib treatment scheduled in a 21-day cycle (1.3 mg/㎥ as a single i.v. bolus on days 1, 4, 8, and 11).

다기관 기능부전을 초래한 치명적인 삼일열 말라리아 증례

박상원,김동우,박주원,이순일,신영학,김의종,오명돈,최강원 대한감염학회 2005 감염과 화학요법 Vol.37 No.2

삼일열 말라리아는 국내에서 재유행하고 있는 감염질환으로, 일반적으로 양성의 임상경과를 거친다. 저자들은 특이한 질병력이 없이 건강하였던 젊은 성인이 국내에서 삼일열 말라리아에 걸린 후 다기관기능부전과 폐출혈으로 사망한 증례를 경험하였다. 환자의 중증 임상경과를 설명할 만한 특이한 인자가 발견되지 않았다. Vivax malaria is a re-emerging infectious disease in Korea with cumulating 19,416 cases as of December 2003 since 1993. Vivax malaria is generally a benign disease with few severe complications. Even in the worldwide literature, there are only small number of case reports on severe complications. We experienced a fatal vivax malaria in a previously healthy young adult with severe multi-organ failure and fatal massive pulmonary hemorrhage. The patient presented with abdominal pain and shock. There were splenic hemorrhage, disseminated intravascular coagulation, oliguric acute renal failure requiring dialysis, and pulmonary hemorrhage leading the patient finally to death. The initial parasitemia was 2,046/μL. Thin smear and PCR revealed only Plasmodium Vivax. There was no explainable cause of death except for the only serological suggestion of Mycoplasma pneumoniae infection without correlating clinical evidence. This is a first case of fatal vivax malaria in Korea since its re-emergence in 1993. Further case monitoring is needed to define whether this is a index case or an isolated one.

Structures, Nanomechanics, and Disintegration of Single-Wall GaN Nanotubes: Atomistic Simulations

Jeong Won Kang,황호정,Jun-Ha Lee,Ki OH Song,Ki Ryang Byun,Oh-Keun Kwon,Won Young Choi 한국물리학회 2003 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.43 No.I

We have investigated the structural, mechanical, and thermal properties of single-walled GaN nanotubes by using atomistic simulations and a Tersoff-type potential. The Tersoff potential for GaN eectively describes the properties of GaN nanotubes. The nanomechanics of GaN nanotubes under tensile and compressive loadings have also been investigated, and Young's modulus has been calculated. The caloric curves of single-walled GaN nanotubes can be divided into three regions corresponding to nanotubes, the disintegrating range, and vapor. Since the stability or the stiness of a tube decreases with increasing curving sheet-to-tube strain energy, the disintegration temperatures of GaN nanotubes are closely related to the curving sheet-to-tube strain energy.

신부전이 동반된 당뇨병 환자에서 발생된 침습성 모균증 : 수술과 Liposomal amphotericin B 및 GM-CSF 병합 요법에 의한 성공적인 치험 1예

이원영,오기원,임국희,장재혁,이동건,최정현,강무일,신완식,차봉연,이광우,손호영,강성구 대한화학요법학회 1999 대한화학요법학회지 Vol.17 No.4

저자들은 신부전이 동반된 당뇨병 환자에서 발생된 부비동형 모균증에 대하여 수술과 함께 liposomal amphotericin B 및 GM-CSF의 복합치료를 하여 성공적으로 치료한 1예를 경험하였기에 문헌 고찰과 함께 보고하는 바이다. Mucormycosis (zygomycosis) primarily affects diabetic or immunocompromised patients and typically progresses rapidly, necessitating surgical excision and antifungal therapy with amphotericin B. Large doses of amphotericin B are needed for cure, but it has the risk of causing significant renal toxicity. The recent development of liposomal amphotericin B allows antifungal therapy to be administered with potentially improved efficacy and reduced nephrotoxicity. We have experienced a case of paranasal mucormycosis successfully treated with surgery, liposomal amphotericin B and GM-CSF. A 59-year-old male suffering from diabetes mellitus for 6 years was admitted with pain at left maxillary area. He was diagnosed as mucormycosis after cytologic exam on the necrotic nasal mucosa, which showed typical hyphae. He have had diabetic nephropathy with macroproteinuria and had rapidly rising serum creatinine levels with the amphotericin B treatment: creatinine levels reverted to basal level with the use of liposomal amphotericin B. Despite surgical excision and continued antifungal therapy, his infection was not effectively controlled. Therefore, GM-CSF was administered additionally to improve phagocytic activity of leukocytes. He was finally cured after receiving a combination of aggressive surgery, liposomal amphotericin B and GM-CSF. To our knowledge, this is the first detailed clinical description of the treatment of mucormycosis with liposomal amphotericin B in Korea.