고실 사구종과 혼동되었던 침샘 분리종 1예

임종현,김무건,김인식,박철원 대한이비인후과학회 2015 대한이비인후과학회지 두경부외과학 Vol.58 No.11

Salivary gland choristoma is defined as the architecturally normal salivary gland tissues found in abnormal locations. Middle ear salivary gland choristoma usually presents with conductive hearing loss. We present a case of middle ear mass with conductive hearing loss in a 6-year-old boy. A reddish mass was incidentally found behind the normal tympanic membrane. Magnetic resonance image showed the markedly enhancing lesion which was in accordance with glomus tympanicum. Preoperative angiography was performed, but supplying artery and mass was not identified. Surgical exploration was made and the mass was dissected easily without profuse bleeding. Final diagnosis was salivary gland choristoma by histopathology. We discuss the clinical features and management of middle ear salivary choristoma with the review of literature.

DFT calculations for role of non-aqueous electrolyte solvents in Li-O₂ batteries

임종현,( Mahesh Datt Bhatt ),이진용 한국공업화학회 2018 한국공업화학회 연구논문 초록집 Vol.2018 No.1

2010년~2021년 국내 메타버스와 가상세계를 활용한 교육 연구 동향 분석: LDA 기반 토픽 모델링과 시계열 회귀분석을 적용하여

임종현,홍진표,박정민,안미리 한국교육정보미디어학회 2022 교육정보미디어연구 Vol.28 No.2

Using LDA-based Topic Modeling and Time-Series Regression Analysis, this study analyzed educational research trends in domestic virtual environments (Metaverse, Virtual Worlds, and VR) and presented educational implications. The abstracts of 418 domestic academic papers (340 academic papers and 78-degree papers) were collected and analyzed in the Metaverse and Virtual Environment field between 2010 and 2021. LDA-based Topic Modeling Analysis extracted six topics: ‘Social Change and Educational Use in Cultural and Language Education,’ ‘Rehabilitation Training Treatment,’ ‘Disabled Students Intervention/Vocational Education,’ ‘Higher Education Practice Simulation,’ ‘Safety Education Training,’ and ‘School Class Application.’ The Time-Series Regression Analysis with the LDA Topic Modeling Analysis result revealed that all topics were statistically significant and appeared to be hot topics. As a result of the study, future research should consider instructional design, teaching and learning methods, and empirical research examining the essential aspects of the learning process for educational use of the virtual environment in response to social changes. Furthermore, it is necessary to research the learning process in a game-based Metaverse environment such as Roblox and Minecraft, where learners can freely create and change objects. It is expected that the results of this study will be used as primary data in research and related fields on education using virtual environments, including metaverse, in the future. 본 연구는 LDA 기반 토픽 모델링과 시계열 회귀분석을 적용하여 메타버스와 가상세계를 중심으로 국내 가상환경 활용 교육 연구 동향을 분석하여, 교육공학적 시사점을 제시하였다. 분석 데이터로 2010년 ~ 2021년 동안의 메타버스 및 가상세계를 활용한 교육 관련 국내 학술 논문 418편(학술지 논문 340편, 학위논문 78편)의 초록을 수집하여 분석하였다. LDA 기반 토픽 모델링 분석을 통해 ‘사회적 변화 및 문화․언어교육 활용’, ‘재활훈련치료’, ‘장애학생 중재/직업교육’, ‘고등교육실습 시뮬레이션’, ‘안전교육훈련’, ‘학교 수업 적용’으로 6개의 토픽을 추출하였다. LDA 토픽 모델링 분석 결과를 근거로 시계열 회귀분석을 실시하여 토픽별 추세를 파악하였다. 모든 토픽이 Hot 토픽으로 나타났고, ‘사회적 변화 및 문화․언어교육 활용’ 토픽이 가장 큰 증가 추세를 보였으며, 그 다음으로 ‘안전교육훈련’, ‘학교 수업 적용’ 등의 순으로 나타났다. 연구 결과, 가상환경 활용 교육 연구가 2017년부터 상당한 증가의 경향을 보이다가 2021년에 급격히 증가하였다. 향후 연구는 사회적 변화에 부응하는 가상환경 활용 교육을 위한 교수설계, 교수․학습 방법, 학습 과정의 본질적인 면을 살펴보는 실증적 연구 등의 방향성을 제안한다. 또한 학습 과정에서 학습자가 자유롭게 객체를 생성․변경할 수 있는 로블록스나 마인크래프트와 같은 게임 기반 메타버스 환경에서의 학습활동에 대한 연구 등이 필요하다. 본 연구의 결과가 향후 메타버스를 비롯한 가상환경 활용 교육에 대한 연구 및 관련 분야에 기초자료로 이용되기를 기대한다.

전기차 충돌안전성 확보를 위한 BATTERY LAY-OUT BENCHMARKING STUDY

임종현 한국자동차공학회 2015 한국자동차공학회 Workshop Vol.2015 No.10

인후두 역류증 환자에서 Reza Band 사용의 안전성 및 효과: 예비연구

임종현,유병준,이동원,송창면,지용배,태경 대한이비인후과학회 2018 대한이비인후과학회지 두경부외과학 Vol.61 No.8

Background and Objectives The main treatment of laryngopharyngeal reflux disease(LPRD) includes life style modification and proton pump inhibitor (PPI) medication. However,LPRD is sometimes refractory to PPI medication. The Reza band has been developed toexert external pressure on the upper esophageal sphincter thus preventing gastric acid refluxto the larynx and pharynx. The aim of this study was to evaluate safety and efficacy of usingthe Reza band in patients with LPRD. Subjects and Methods We prospectively enrolled 16 LPRD patients who were refractoryto PPI medication and who had agreed to wear the Reza band. Patients were treated with theReza band and PPI medication simultaneously or only the Reza band. We studied complicationsrelated to the Reza band, analyzed Reflux Symptom Index (RSI) and Reflux Finding Score(RFS) before and after the application of the band up to 12 weeks. Results The Reza band was endured by 15 patients except one patient. One patient (6.25%)ceased wearing the band due to pain and discomfort in the neck. No major complications occurred,except one patient who reported mild neck discomfort when the band was applied. The mean value of RSI before the application of the Reza band was 12.31±6.43, which significantlyimproved at 8 weeks and 12 weeks (9.17±5.08, p=0.005 and 8.20±5.59, p=0.007, respectively)post-treatment. The mean value of RFS before the application of the Reza band was13.50±2.97, which significantly improved at 2, 4, 8, and 12 weeks (p<0.05) post-treatment. Conclusion We conclude that the Reza band is safe and effective for the treatment of LPRDin properly selected patients.

자발성 소뇌출혈의 치료방법과 예후

임종현,윤일규,도재원,배학근,이경석,이인수 대한신경외과학회 1990 Journal of Korean neurosurgical society Vol.19 No.3

We analysed a series of 35 patients with primary cerebellar hemorrhage, diagnosed by computerized tomography scanning from 1985 to 1988. They constituted 6.6% of spontaneous intracerebral hemorrhages (35 out of 530) who were admitted during the same period. There were 13 men and 22 women. The site of hemorrhage was vermis in 15 patients and hemisphere in 20 patients. On admission, the Glasgow Coma Scale(GCS) value was less than 10 in 15 patients(42.3%) and not less than 10 in 20 patients(57.1%). Quadrigerminal cistern was normal in 11 patients(31.4%), partially obliterated in 15 patients(42.9%), and completely obliterated in 9 patients(25.7%). The largest diameter of the hematoma was less than 3cm in 15 patients(42.9%) and larger than 3cm in 20 patients( 57.2%). Hydrocephalic change was observed in 21 patients( 60%). The hematoma was removed via suboccipital craniectomy in 16 patients(45.7%) and managed conservatively in II patients(31.4%). In 8 patients(22.9%), external ventricular drainage was performed. The method of treatment was different according to the GCS value on admission, the status of the quadrigeminal cistern, the presence of hydrocephalic change, and the size of hematoma. Overall mortality rate was 22.9%. These results suggested that the conservative treatment can be done in patients with (1) high GCS value(not less than 10), (2) patent quadrigeminal cistern, (3) absent hydrocephalic change, and (4) small sized hematoma(less than 3cm). If not, surgical treatment should be considered.

Theoretical Approach to Investigate Photocatalytic Acitivity of TiO₂ Nanoparticles

임종현,남연식,이진용 한국공업화학회 2019 한국공업화학회 연구논문 초록집 Vol.2019 No.1

TiO₂ has been highlighted as eco-friendly energy source due to its photocatalytic activity. However wide band gap of TiO₂ lower photocatalytic performance. There have been a lot of efforts to enhance the activity by modifications such as nanostructuring, oxygen defects, chemical doping. Investigating effects of these modifications on light absorption and charge recombination by experimental method is limited due to inevitable presence of defect and ununiformed particles. In order to overcome this limit, theoretical approaches are needed. The density functional theory (DFT) methods and modeling for analyzing TiO₂ nanoparticles are discussed. Furthermore, chemical modification strategies such as band engineering by controlling structure of TiO₂ nanoparticles and introducing oxygen defects or chemical doping are also discussed. Finally, theoretical studies on excited state dynamics involving charge carrier separation, diffusion, and recombination are discussed.

Investigation of Morphology and Physical Properties of Segmented Polyurethaneureas

임종현,조남주 한국공업화학회 2005 한국공업화학회 연구논문 초록집 Vol.2005 No.-

Electrical properties of metal-ferroelectric-insulator-semiconductor structure with Lanthanum Dysprosium Oxide and SrBi_2Ta_2O_9

임종현,Kwi-Jung Kim,Gui-Zhe An,박병은 한국물리학회 2011 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.59 No.31

The metal-ferroelectric-insulator-semiconductor (MFIS) structure using SrBi_2Ta_2O_9 (SBT) film as a ferroelectric layer and lanthanum dysprosium oxide (LDO) film as an insulating buffer layer was prepared. The LDO thin film and SBT film were deposited by sol-gel method. The sol-gel derived LDO thin films on Si had very flat and smooth surface morphologies. The equivalent oxide thickness (EOT) values were about 10.1 nm, 12.5 nm, and 12.8 nm for 750 ˚C, 800 ˚C, and 850 ˚C, respectively. Also, the relative dielectric constant of 750 °C-annealed, 800 °C-annealed and 850 °C-annealed LDO films were about 15.4, 12.5, and 12.2, respectively. On the whole, the leakage current densities showed the good characteristics regardless of the annealing temperature variations. Especially, the leakage current property of the 850 °C-annealed LDO film was visibly superior to the others over 6V. The C-V characteristics of Au/SBT/LDO/Si structure showed clockwise hysteresis loops, and the memory window width increased as the bias voltage increased. Also, the leakage current density was lower than 5 ×10^(-7) A/cm^2

느타리버섯의 갓색 관련 laccase의 발현에 관한 연구

임종현,송민진,김경윤,손은숙,조영섭,조중호,이창수 한국버섯학회 2007 버섯 Vol.11 No.1

Laccase는 균류와 식물에서 광범위하게 알려진 효소로서 다양한 기질에 대하여 촉매반응을 나타낸다. 오래 전부터 펄프산업에서 리그닌의 제거와 섬유소의 표백작업, 그리고 오염 된 물과 토양의 복원 등의 여러 응용성에서 잠재적인 산업적 효소로서 주목을 받고 있다. 현재는 버섯의 자실체로부터 세포내 효소의 작용에 대한 연구가 시작되었으며, 최근에는 표고버섯의 자실체에서 laccase가 melanin의 생합성에 중요한 역할을 하고 있음이 보고된 바 있다. 이에 우리는 일정한 조건에서 특정한 색의 갓을 보이는 느타리버섯에서 흑색 및 갈색을 나타내는 색소인 melanin과의 연관성을 laccase의 효소활성으로 확인고자 하였다. 시료는 느타리버섯에서 분리한 흑색 및 백색의 갓 색 변이체를 사용하였으며, 생활 주기와 자실체의 부위별로 나누어 각각 효소활성을 측정하여 비교하였다. 버섯시료를 sodium phosphate 완충액에서 homogenizing한 후 원심분리하여, 그 상등액을 조효소액으로 사용하였다. Laccase 활성은 McIlvaine 완충액상에서 2,2'-azino-bis(3-ethylbenthiazoline-6-sulfonic acid) diammonium salt (ABTS)를 기질로 사용하여 효소와 반응시켰으며, ABTS의 산화에 의해 생성된 산화물을 ELISA를 통해서 측정하였다. 그 결과, laccase 효소활성은 갓 색 변이체(흑, 백색)의 자실체 중에서 흑색 자실체가 가장 높았으며, 생활주기별(균사체, 원기, 자실체, 포자)에서는 균사체가 가장 높았다. 또한, 느타리버섯의 자실체 부위별(갓, 갓껍질, 갓주름, 줄기)에서는 갓 껍질이 가장 높은 것으로 확인되었다.