• 제목/요약/키워드: Seong-Ho School

검색결과 1,503건 처리시간 0.034초

TEOS 와 TPAOH 출발물질을 이용한 나노 크기의 제올라이트 합성 (Synthesis of nanosized MFI zeolite using TEOS and TPAOH precursors)

  • 배혜진;최병호;조성훈;원수현;이보경;옥해렬
    • 한국기계가공학회지
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    • 제13권3호
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    • pp.22-27
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    • 2014
  • Nanosized zeolite was prepared in an autoclave at a hydrothermal temperature range of 100 to $170^{\circ}C$. In TEM and particle-size analyses, the size of the nanosized powders was found to be 10-300 nm, and its distribution is uniform and spherical, depending on the hydrothermal temperature. XRD confirms that the nanosized powder is MFI zeolite.

가역적인 뇌기능장애를 보인 MELAS 증후군 (Reversible Brain Dysfunction in MELAS Syndrome)

  • 정진성;이학승;박현영;장혁;김요식;조광호
    • Annals of Clinical Neurophysiology
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    • 제8권1호
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    • pp.84-87
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    • 2006
  • The MELAS (Mitochondrial Encephalomyopathy with Lactic Acidosis, and Stroke-like episodes) syndrome is one of the inherited mitochondrial disorder. We have experienced a 16-year-old girl with headaches and left hemianopsia. Diagnosis of MELAS syndrome with multiple brain parenchymal lesions was confirmed by gene study. The stroke-like lesion of MELAS syndrome showed significant improvement in radiological follow up study. Therefore, MRI findings in MELAS could be interpreted as metabolic cellular dysfunction rather than ischemic vasculopathy.

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Thickness Effects on Electrical Properties of PVDF-TrFE (51/49) Copolymer for Ferroelectric Thin Film Transistor

  • Kim, Joo-Nam;Jeon, Ho-Seung;Han, Hui-Seong;Im, Jong-Hyung;Park, Byung-Eun;Kim, Chul-Ju
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2007년도 추계학술대회 논문집
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    • pp.130-131
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    • 2007
  • In this study, polyvinylidene fluoride/trifluoroethylene (PVDF-TrFE) was investigated. For a metal-ferroelectic-metal (MFM) structure, We obtained that the 70 nm-thick film showed the maximum polarization of $8.24\;{\mu}C/cm^2$, 2Pr of $6\;{\mu}C/cm^2$ and the coercive voltage of ${\pm}3.1\;V$ at 12 V. The 140 nm-thick film showed higher performance. However, the thicker film required a higher voltage. The current density was $10^{-6}{\sim}10^{-7}\;A/cm^2$ under 15 V. We can expect from these results that the electrical properties of the devices particularly ferroelectric thin film transistor using PVDF-TrFE copolymer, be able to be on the trade-off relationship between the remanent polarization and the leakage current.

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사고 발생에 대비한 OBD2 차량 운행 정보 블랙박스 (OBD2 Vehicle Operation Information Black Box System for Accident Preparedness)

  • 김준영;김준희;오형성;최재형;고경호;류명춘
    • 한국컴퓨터정보학회:학술대회논문집
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    • 한국컴퓨터정보학회 2024년도 제69차 동계학술대회논문집 32권1호
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    • pp.279-280
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    • 2024
  • 본 논문에서는 주행 중 차량의 상태를 실시간으로 모니터링함과 동시에, 페달 조작 여부를 확인할 수 있는 영상 촬영 및 저장 시스템을 제안한다. 개발된 차량 운행 정보 블랙박스는 블루투스 OBD2 커넥터를 통해 차량의 PID 값을 식별하고 수집한다. 이 데이터는 비동기 방식으로 처리되며, 라즈베리파이와 7인치 터치 디스플레이를 이용해 운전자에게 한눈에 보일 수 있는 형태로 정보를 제공한다. 특히, 멀티스레드를 활용하여 ECU 정보를 페달 조작 여부 영상에 표시하는 동시에 녹화하고, CSV 파일로 SD 카드에 실시간으로 저장한다. 수집된 차량 데이터와 영상 데이터는 예기치 못한 사고 발생 시 운전자의 과실 비율 측정과 대처행동을 입증하는 데 중요한 역할을 할 것으로 기대되며, 차량 정비 시 참고 자료로 활용될 수 있다.

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조구등이 Glucose Oxidase로 손상된 대뇌신경세포에 미치는 효과 (Effect of Ramulus et uncus uncariae on Glucose Oxidase-Induced Toxicity in Cultured Cerebral Neurons)

  • 김형수;이용석;오석규;이강창;이건목;이정원;이상복;김종호;유준기;강영성;김성수;송호준;박승택
    • 동의생리병리학회지
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    • 제16권5호
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    • pp.1016-1019
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    • 2002
  • To examine the cytotoxic effect of glucose oxidase(GO) in cultured mouse cerebral neurons, cytotoxicity was measured by MTT assay after cultured nerve cells were incubated for 3 hours in the media containing 1 ~ 60mU/ml concentrations of GO. In addition, the neuroprotective effect of Ramulus et uncus uncariae(REUU) was determined by MTT assay in these cultrures. Cell viability was remarkably decreased in a dose- and time-dependent manner after cultured mouse cerebral neurons were exposed to 30mU/ml GO for 3 hours. In the neuroprotective effect of REUU on GO-induced toxicity, REUU blocked the GO-mediated neurotoxicity in these cultures. From above the results, it suggests that GO is toxic in cultured mouse cerebral neurons and selective herb extract such as REUU is effective in prevetion of the neurotoxicity induced by GO.

지구통계 기법을 활용한 토양 오염범위 산정 및 불확실성 평가 (Evaluation of Geostatistical Approaches for better Estimation of Polluted Soil Volume with Uncertainty Evaluation)

  • 김호림;김경호;윤성택;황상일;김형돈;이군택;김영주
    • 한국지하수토양환경학회지:지하수토양환경
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    • 제17권6호
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    • pp.69-81
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    • 2012
  • Diverse geostatistical tools such as kriging have been used to estimate the volume and spatial coverage of contaminated soil needed for remediation. However, many approaches frequently yield estimation errors, due to inherent geostatistical uncertainties. Such errors may yield over- or under-estimation of the amounts of polluted soils, which cause an over-estimation of remediation cost as well as an incomplete clean-up of a contaminated land. Therefore, it is very important to use a better estimation tool considering uncertainties arising from incomplete field investigation (i.e., contamination survey) and mathematical spatial estimation. In the current work, as better estimation tools we propose stochastic simulation approaches which allow the remediation volume to be assessed more accurately along with uncertainty estimation. To test the efficiency of proposed methods, heavy metals (esp., Pb) contaminated soil of a shooting range area was selected. In addition, we suggest a quantitative method to delineate the confident interval of estimated volume (and spatial extent) of polluted soil based on the spatial aspect of uncertainty. The methods proposed in this work can improve a better decision making on soil remediation.

Risk Factors for Pneumonia in Ventilated Trauma Patients with Multiple Rib Fractures

  • Park, Hyun Oh;Kang, Dong Hoon;Moon, Seong Ho;Yang, Jun Ho;Kim, Sung Hwan;Byun, Joung Hun
    • Journal of Chest Surgery
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    • 제50권5호
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    • pp.346-354
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    • 2017
  • Background: Ventilator-associated pneumonia (VAP) is a common disease that may contribute to morbidity and mortality among trauma patients in the intensive care unit (ICU). This study evaluated the associations between trauma factors and the development of VAP in ventilated patients with multiple rib fractures. Methods: We retrospectively and consecutively evaluated 101 patients with multiple rib fractures who were ventilated and managed at our hospital between January 2010 and December 2015, analyzing the associations between VAP and trauma factors in these patients. Trauma factors included sternal fracture, flail chest, diaphragm injury, traumatic aortic dissection, combined cardiac injury, pulmonary contusion, pneumothorax, hemothorax, hemopneumothorax, abbreviated injury scale score, thoracic trauma severity score, and injury severity score. Results: Forty-six patients (45.5%) had at least 1 episode of VAP, 10 (21.7%) of whom died in the ICU. Of the 55 (54.5%) patients who did not have pneumonia, 9 (16.4%) died in the ICU. Using logistic regression analysis, we found that VAP was associated with severe lung contusion (odds ratio, 3.07; 95% confidence interval, 1.12 to 8.39; p=0.029). Conclusion: Severe pulmonary contusion (pulmonary lung contusion score 6-12) is an independent risk factor for VAP in ventilated trauma patients with multiple rib fractures.

FDTD를 이용한 PBG 구조를 갖는 마이크로스트립 대역저지 여파기에 관한 분석 (Analysis of Microstrip Bandstop Filter Based on the Photonic Bandgap(PBG) Structure Using FDTD)

  • 호진기;윤영설;박상현;최영완;김형석;김호성
    • 정보통신설비학회논문지
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    • 제2권1호
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    • pp.52-62
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    • 2003
  • 본 논문에서는 그라운드 판에 주기적으로 에칭된 원으로 구성된 Photonic Bandgap(PBG) 여파기가 광대역 하모닉 성분을 제거할 수 있음을 보인다. FDTD법과 제작, 실험을 통해 얻은 결과를 이용하여 PBG 구조의 특성을 분석해 보았고, FDTD법은 다양한 3차원 구조를 시뮬레이션을 할 수 있고 광대역의 주파수 응답을 볼 수 있다. 분석 결과는 에칭된 원들을 2차원으로 배열한 경우와 일렬로 배열한 경우 모두 똑같은 결과가 나오는 것을 나타냈다. 그리고 에칭된 원과 원 사이의 공진기의 특성을 필드패턴을 통해서 알아 보았고, 에칭된 원들의 수 n, 에칭된 원의 반지름 r과 주기 a의 변화에 따른 주파수의 특성을 보았다.

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마이크로캡슐 잠열재 슬러리를 적용한 증기압축식 냉동기의 성능 모델링 (Simulation of Refrigeration System with MPCM Slurry as Secondary Fluid)

  • 최종민;김용찬;천덕우;강훈;윤준상;조한호;김영배;이호성;최광민;강용화;전종욱
    • 설비공학논문집
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    • 제18권6호
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    • pp.501-508
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    • 2006
  • MPCM (Microencapsulated Phase Change Material) slurries show several advantages over the sensible heat transportation system. In this study, a numerical model for a vapor compression refrigeration system using MPCM slurries as a secondary fluid through an evaporator was developed, and the system performance was compared with that using water. Generally, the MPCM system showed higher performance than the water system. The COP of the MPCM system was higher by 16.6 to 18.6% than that of the water system at all conditions. The MPCM slurry yields better performance in the aspect of heat transfer and heat transportation comparing to the sensible heat transfer medium such as water.

백굴채(白屈菜) 추출물의 피지생성 억제효과 (Inhibitory Effect of Extract of Chelidonii Harba on Sebum Synthesis)

  • 최두호;박시준;김호민;노성택;유일수;문연자;임규상;우원홍
    • 동의생리병리학회지
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    • 제20권6호
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    • pp.1561-1566
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    • 2006
  • Sebum is secreted due to the effect of androgen, which start to be secreted at puberty. Androgens have profound effects on the physiology of the sebaceous gland, Using the human sebocyte cell line SZ95, we investigated the inhibitory effect of Chelidonii Harba (CH) on the subum production. Our results showed that numerous cytoplasmic lipid droplets were examined by Oil red staining and lipid droplets were increased markedly by testosterone. Cell viability was dose-dependently decreased by CH as compared with untreated cells, while total lipid content and cholesterol slightly were increased by CH. Testosterone significantly stimulated the synthesis of total lipid and the synthesis of specific sebaceous lipids such as cholesterol and triglyceride. Combined treatment with CH and testosterone resulted in a lower lipid synthesis than with testosterone alone. Especially cholesteol content was reduced by combined treatment with CH and testosterone. These results indicate that CH inhibits the testosterone-induced lipid synthesis in SZ95 cells and acts antagonistically to androgen at the cellular level.