Characteristics of Hydrogen Storage Alloy p-GaN Ohmic Contacts for InGaN LEDs

Seung Wan Chae,June O Song,Mi Yang Kim,Suk Kil Yoon,성태연,김태근,곽준섭 한국물리학회 2006 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.49 No.3

We report the electrical and the optical properties of ZnNi/Au electrodes and compare them to those of Ni/Au electrodes. From the experiment and a systematic analysis using fabricated InGaN/GaN multiple-quantum-well (MQW) light-emitting diodes (LEDs) with ZnNi/Au (5 nm/5 nm) electrodes, the forward voltage with ZnNi/Au was compared with the values of 3.45 V and 22 mW, respectively for Ni/Au under the same conditions. We attribute this to both the reduced bar- rier height of p-type GaN and the enhanced mobility of Mg-doped GaN, due to hydrogen absorption by ZnNi

응급의료센터를 내원한 소아 환자 중 신경계 질환의 경향 분석

박승완(Seung Wan Park)ㆍ채수안(Soo Ahn Chae)ㆍ이재희(Jae Hee Lee)ㆍ이정주(Jung Ju Lee)ㆍ윤신원(Shin Won Yoon)ㆍ임인석(In Seok Lim)ㆍ최응상(Eung Sang Choi)ㆍ유병훈(Byoung Hoon Yoo) 대한소아신경학회 2010 대한소아신경학회지 Vol.18 No.1

목 적:소아 응급 환자, 특히 발작이나 의식의 변화 또는 소실을 주소로 내원하는 환자들을 조기에진단하고, 적절하게 응급 조치를 한다면 심각한 합병증과 후유증 또는 사망을 예방할 수 있다. 지금까지 국내에서 응급의료센터에 내원한 신경계 질환 환자들에 대한 검증은 거의 없는 실정이나 외국에서는이미 여러 나라에서 조사가 이루어졌다. 신경계 질 환은 나라마다, 지역마다 다른 분포를 보이므로 우리나라의 자료를 분석하는 일은 의미가 있다고 하겠다.방 법: 2005년 1월 1일부터 2008년 12월 31일까지 중앙대학교병원 응급의료센터에 내원하여소아청소년과 진료를 받은 18세 미만의 환자 총18,922명 중 신경계 질환으로 최종 진단된 환자1,058명(5.6%)을 대상으로 하였다. 각 례에 대해응급 의무 기록지와 입원 병록지를 참고하였고, 이를 근거로 연령별 질환군, 계절별 질환군을 분석하였으며, 주증상별 최종 진단명을 후향적으로 조사하였다.결 과:남녀비는 1.5:1이었고, 연령별 분포상 2세부터 5세 미만이 가장 많았고 평균 연령은 3세였 다. 연령에 따른 흔한 질병은, 영유아기에는 열성경련이, 학령기에는 뇌수막염이, 청소년기에는 간질과두통이 가장 흔하였다. 계절별 분포는 2005년부터2007년까지는 계절별 차이가 크지 않았으나, 2008년에는 여름철에 내원한 환자수가 가장 많았다. 여름에는 뇌수막염이 다른 계절에 비해 월등히 많았으나, 다른 질환은 계절별 차이가 크지 않았다. 주증상 별 분포는 발작, 열, 두통, 구토의 순으로 많았으며,최종 진단명별 분포로는 열성경련(51%), 간질(21%), 뇌수막염(18%) 순으로 많았다. 최종 진료 형태별 분포로는 입원(70.0%), 귀가(27.9%), 자의퇴원(1.5%), 전원(0.6%) 순이었다. 신경계 질환의입원율은 전체 환자의 입원율(22.8%)이나 다른 계통 질환의 입원율 보다 높았다.결 론 : 신경계 질환 환자의 수는 매년 증가하고있으며, 다른 계통 질환에 비해 입원율이 높은 특성을 가지고 있다. 이는 보호자들의 불안과 신경계 질 환의 중증도와 관련이 있으므로 신경계 증상을 보이는 환자들을 조기에 진단하고 적극적으로 치료하는것 뿐만 아니라, 보호자들에게 충분한 설명을 하고안심을 시키는 것도 중요할 것으로 생각된다. Purpose : Pediatric emergencies with seizure and decreased mental status or loss of consciouseness may cause severe complications without early proper management. Distribution of neurological disorders may differ according to various demographics, it would be valuable to evaluate recent data in Korea. Methods : Patients who had neurological problems and below 18 years old were defined as case. 1,058(5.6%) cases who visited the emergency department of Chung-Ang University Hospital from January 2005 to December 2008 were analyzed. The patients were also divided into four age groups: age 1 year or younger, preschool children(2-5 years), middle childhood group(6-10 years), and adolescent group(11-18 years). Results : The male to female ratio was 1.5:1. Most children were between 2 to 5 years old(mean age=3 years). Febrile convulsion is the most common neurological disorders among infant and preschooler, meningitis is the most common among middle childhood, epilepsy and headache is the most common among adolescent. Main initial presentations were seizure followed by fever, headache and vomiting. Febrile convulsion was the most common neurological disorders followed by epilepsy and meningitis. Final dispositions of patients were admission, discharge, against medical device, and transfer to other hospital. Admission rate of patients with neurological disorders was higher than those of total patients. Conclusion : Neurological disorders are increasing in pediatric emergencies and have highest admission rate, mostly because of the parent's anxiety and severity of disease itself. Therefore, not only detect and treat neurological disorder in early stage, but also reassuring parent is important.

텍스타일 디자인 분류 및 관심 영역 도출에 대한 연구

채승완(Seung Wan Chae),이병우(Byoung Woo Lee),이우창(Woo Chang Lee),이충권(Choong Kwon Lee) 한국스마트미디어학회 2021 스마트미디어저널 Vol.10 No.2

디자인에 있어서 유사한 디자인들을 그룹핑하여 분류하는 것은 관리적인 측면에서 효율성을 높여주고 사용적인 측면에서는 편의성을 제공한다. 본 연구는 인공지능 알고리즘을 이용하여 텍스타일 디자인을 도트, 꽃무늬, 줄무늬, 그리고 기하학으로 4개의 카테고리로 분류하고자 하였다. 특히, 인공지능의 관점에서 분류의 근거가 되는 관심 영역을 찾아내고 설명할 수 있는 지를 탐색하였다. 총 4,536개의 디자인을 8:2의 비율로 무작위 추출하여 학습용 데이터 3,629개와 테스트용 데이터 907개로 구성하였다. 분류에 사용된 모델은 VGG-16과 ResNet-34로 두 모델의 꽃무늬 디자인에 대한 정밀도는 각각 0.79%, 0.89%이며, 재현율은 0.95%, 0.38%로 우수한 분류 성과를 보였다. LIME(Local Interpretable Model-agnostic Explanation) 기법을 이용하여 분석한 결과에 따르면, 기하학과 꽃무늬 디자인의 경우 도형과 꽃잎 부분이 분류의 근거가 되는 관심 영역으로 도출되었다. Grouping and classifying similar designs in design increase efficiency in terms of management and provide convenience in terms of use. Using artificial intelligence algorithms, this study attempted to classify textile designs into four categories: dots, flower patterns, stripes, and geometry. In particular, we explored whether it is possible to find and explain the regions of interest underlying classification from the perspective of artificial intelligence. We randomly extracted a total of 4,536 designs at a ratio of 8:2, comprising 3,629 for training and 907 for testing. The models used in the classification were VGG-16 and ResNet-34, both of which showed excellent classification performance with precision on flower pattern designs of 0.79%, 0.89% and recall of 0.95% and 0.38%. Analysis using the Local Interpretable Model-agnostic Explanation (LIME) technique has shown that geometry and flower-patterned designs derived shapes and petals from the region of interest on which classification was based.

Poster Session:PS 0494 ; Nephrology : Effects of Acute Kidney Injury and Chronic Kidney Disease on Long-Term Mortality After Coronary Artery Bypass Grafting

( Seung Seok Han ),( Na Ra Shin ),( Seon Ha Baek ),( Shin Young Ahn ),( Dong Ki Kim ),( Se Joong Kim ),( Ho Jun Chin ),( Dong Wan Chae ),( Ki Young Na ) 대한내과학회 2014 대한내과학회 추계학술발표논문집 Vol.2014 No.1

Background: Both acute kidney injury (AKI) and chronic kidney disease (CKD) are important issues in patients undergoing coronary artery bypass grafting (CABG), particularly with regard to mortality. However, their synergistic or discrete effects on longterm mortality remain unresolved. Methods: A total of 1899 patients undergoing CABG were retrospectively analyzed. The adjusted hazard ratios (HRs) for all-cause mortality were calculated after stratifying the timeframes. To evaluate the synergistic effects between AKI and CKD, the relative excess risk due to interaction (RERI) was applied. Results: The presence of AKI, CKD, or both increased the HRs for mortality, compared with the absence of both: AKI alone, 1.84 (1.464-2.319); CKD alone, 2.46 (1.735-3.478); and AKI and CKD together, 3.21 (2.301-4.488) [figure 1]. However, the relationships with mortality were different between AKI and CKD, according to the timeframes: AKI primarily affected early mortality, particularly within 3 years, whereas CKD had a relatively constant effect on both the early and the late periods. When the parameters from the RERI were obtained, there was a synergistic effect on early mortality between AKI and CKD. Conclusions: The relationships with mortality following CABG were different between AKI and CKD. However, their effects were not exclusive but synergistic.

Alterations of gene expression in the hippocampus of 8-month wild-type and humanized APPsw transgenic mice

Seung Wan Jee,Byoung Guk Kim,Jin Hee Park,Dae Youn Hwang,Sun Bo Shim,Su Hae Lee,Ji Soon Sin,Chang Joon Bae,Byoung Chun Lee,Cheul Kyu Kim,Kab Ryong Chae 한국실험동물학회 2007 한국실험동물학회 학술발표대회 논문집 Vol.2007 No.-

Molecular Mechanisms of Neurologic Disorders(Neurobiology) : Gene expression profiles of nicotine-induced changes in the brain of transgenic mice

( Seung Wan Jee ),( Sun Bo Shim ),( Byoung Guk Kim ),( Dae Youn Hwang ),( Su Hae Lee ),( Ji Soon Sin ),( Chang Jun Bae ),( Cheul Kyu Kim ),( Jong Min Woo ),( Hye Young Oh ),( Kab Ryong Chae ) 생화학분자생물학회 2008 생화학분자생물학회 춘계학술발표논문집 Vol.2008 No.-

범혈구 감소와 혈구 탐식소견을 보인 쯔쯔가무시병 1예

채석래,박언섭,이종민,곽승민,강문원,양철우,신완식,방병기 대한감염학회 1992 감염 Vol.24 No.3

Benign hemophagocytic syndrome is usually associated with systemic viral infection and occasionally occurs with bacterial, fungal and protozoal infections. In our knowlege, hemophagocytic syndrome associated with scrub typhus has not been prevously reported. We experienced a case of rickttsia-asssociated pancytopenia and hemophagocytosis in a 22-year old man who admitted to our hospital for high fever, chill, myalgia, and abdominal pain. It was speculated that scrub typhus may be one of the causes of benign hemophagocytic syndrome.

Takayasu동맥염의 임상적고찰

채성철,강승완,우언조,전재은,박의현,김기식,김윤년,김권배 慶北大學校 醫科大學 1989 慶北醫大誌 Vol.30 No.4

경북대학교병원 및 계명대학교의과대학 부속병원에 입원하였던 28례의 Takayasu동맥염환자의 임상적관찰을 하여 다음과 같은 성적을 얻었다. 1) 대상환자 28례중 남자가 7례, 여자가 21례였고, 남자의 평균연령은 44세, 여자의 평균연령은 21세, 전체환자의 평균연령은 27세였다. 2) 내원당시의 28례의 증상으로는 운동성호흡곤란(11례), 현기증(7례), 두통(7례), 무맥(4례), 전신쇠약감(3례), 시력장애(3례), 이상감각(3례), 복통(3례), 심계항진(2례), 흉통(1례)등이 있었다. 초기증상을 알 수 있었던 16례에서의 초기증상은 전신쇠약감 또는 피로감(8례), 국소동통(4례), 관절통(3례), 야간발한(3례), 흉통(3례), 발열(2례), 체중감소(2례), 식욕부진(1례)등이었다. 이들에서의 잠복기(latent period)는 42일에서 10년이상까지 다양하였다. 동반된 질환으로는 결핵이 2례, 류마티양관절염, 당뇨병, Valsalve동의 동맥류, 위점막 병변 및 사구체신염이 각각 1례씩 있었다. 3) 내원당시의 주요 이학적소견으로는 무맥(25례), 고혈압(16례), 병변부위동맥의 잡음(bruit)(12례), 울혈성심부전(11례), 고혈압성망막증(10례), 하지의 파행(8례), 폐동맥고혈압(2례) 및 대동맥판폐쇄부전과 승모판폐쇄부전(2례) 등이었다. 4) 검사실소견으로는 빈혈(10례), 혈침속도증가(22례)가 있었고, 그외 비특이적으로 CRP양성(13례중 9례), RA factor양성(13례중 3례) 및 ANA, LE세포, VDRL양성(13례중 1례)등이 있었고, Man toux검사는 시행한 11례중 3례에서 양성반응을 보였다. 심전도소견으로는 재분극이상(12례), 좌심비대소견(7례), QT간격연장(4례), 좌심방이상소견(2례) 및 심방세동, 발작성심방빈맥과 흉부유도에서의 R파의 "poor progression"(각각 1례)등이었다. 5) 동맥조영술소견은 Lupi-Herrera등의 1형이 11례, 2형이 6례, 3형이 9례 및 4형이 2례였다. 6) 치료받은 19례가운데 내과적치료를 받은 17례중 11례에서 부신피질호르몬제를, 10례에서는 항응고제를 사용하였는데, 부신피질호르몬제를 투여받은 4례에서만 혈침속도의 감소가 있었다. 그리고 고혈압치료를 위하여 경피적신동맥확장술이 7례에서, 신절제술이 1례에서 시행되었다. 7) 15례에서 추적관찰이 가능하였고, 이가운데 4례는 사망하였으며, 생존하고 있는 11례의 평균 추적관찰기간은 7개월(1.5-24개월)이었다. 사망한 4례중 3례는 심부전으로, 1례는 농흉에 의한 패혈증으로 사망하였다. Clinical observation on 28 cases of Takayasu's arteritis from Departments of Internal Medicine of Kyungpook National University and Keimyung University revealed followings: 1) Age and sex distribution: Seven cases were male and twenty one cases were female. Mean ages of male and female cases were 44 and 21 years old, respectively (range 11-66 years old). 2) Chief complaints on first presentation were dyspnea on exertion (11 cases), dizziness (7 cases), headache (7 cases), absence of pulse (3 cases), abdominal pain (3 cases), palpitation (2 cases), and chest pain (1 case). Initial systemic symptoms of 16 cases which could be recalled were generalized weakness and fatigue (8 cases), localized pain (4 cases), arthralgia (3 cases), night wsweating (3 cases), chest pain (3 cases), fever (2 cases), weight loss (2 cases), and anorexia (1 case). Latent periods of these cases were ranged from forty-two days to over 10 years. Concomittant diseases were pulmonary tuberculosis (2 cases), rheumatoid arthritis (1 case), diabetes mellitus (1 case), aneurysm of sinus of Valsalva (1 case), gastric mucosal lesion (1 case), and glomerulonephritis (1 case). 3) Among the physical findings were absence of pulse (25 cases), hypertension (16 cases), bruits over affected arteries (12 cases), congestive heart failure (11 cases), hypertensive retinopathy (10 cases), claudication of lower extremities (8 cases), pulmonary hypertension (2 cases), and aortic and mitral regurgitations (2 cases). 4) There were no specific laboratory findings. Among nonspecific findings were anemia (10 cases), increased ESR (22 cases). C-reactive protein, RA factor were positive in nine and three cases, respectively, of 13 cases tested. Antinuclear antibody, LE cell and VDRLK were positive only in a case of 13 cases tested. Mantoux test was positive in three of 11 cases tested. Electrocardiogram revealed abnormal repolarization (12 cases), findings of left ventricular hypertrophy (7 cases), prolongation of QT interval (4 cases). 5) According to angiographic findings, 11, 6, 9 and 2 cases had type 1, type 2, type 3 and type 4 of Lupi-Herrera and associates, respectively. 6) In 19 cases who were treated, 17 cases were given medical treatment of corticosteroid (11 cases) and/or oral anticoagulant (10 cases). Four cases on corticosteroid showed decrease in ESR. Percutaneous angioplasty of renal artery was performed in seven cases with hypertension, and successful in 4 cases in which blood pressures were normalized. In another hypertensive case, nephrectomy normalized blood pressure. 7) Follow-up observations were possible in 15 cases, of which 4 cases died. Average follow-up duration was seven months (range 1.5-24 mopnths). Causes of death were congestive heart failure in three cases, and pyothorax related sepsis in a case.

Evaluation of the fracture resistance of all-ceramic zirconia posts by 3 different methods

Jeong, Seung-Mi,Chung, Chae-Heon,Kang, Dong-Wan,Ludwig, Klaus,Kern, Matthias,Huels, Alfons The Korean Academy of Prosthodonitics 2000 대한치과보철학회지 Vol.38 No.6

Statement of the problem. All-ceramic post-and-core restorations offer a number of advantages compared with systems that use metal build-ups. In certain clinical cases, however, fractures at the joint between the post and core build-up have been reported. Purpose. The objective, therefore, is to improve the joint between the post and the core build-up. Material and methods. Three different methods were used to prepare all-ceramic post-and-core restorations; pressing IPS Empress core build-ups to CosmoPost zirconia posts, cement-ing IPS Empress core build-ups to CosmoPost zirconia posts and Celay-milling of zirconia blanks. A series of ten restorations was prepared for each of the three methods. The post-and-core complexes were tested to failure with the load applied perpendicular to the post axis. The load and deflection at fracture were recorded. Results. The highest breaking load and highest deflection were recorded for the cementing technique with values of 25.3 N and $394{\mu}m$, respectively, The corresponding values for the pressed core build-ups and the milled zirconia core build-ups were 22 N and $301{\mu}m$, and 13 N and $160{\mu}m$, respectively. All the differences are statistically significant (p=0.05). Regarding the load-dependence of the deflection, the cemented core build-ups again demonstrated the highest value with $15.5{\mu}m/N$. The difference in the values of $13.6{\mu}m/N\;and\;13{\mu}m/N$ recorded for the pressed-on and milled core build-ups, respectively, were statistically insignificant. Conclusion. In regard to the high fracture resistance of zirconia post, adhesive cementing the core build-up to the post offers a viable alternative to the conventional pressing technique. The elastic bond between the rigid high-strength zirconia post and the core build-up presents an additional advantage.

Nutrigenomics Study on Antifatigue Effect of Cordyceps Mycelium Extract (Paecilomyces hepiali)

Soo-Wan Chae,Fusako Mitsunaga,Su-Jin Jung,Ki-Chan Ha,Hong-Sig Sin,Seung-Hwan Jang,Shin Nakamura 한국식품영양과학회 2014 한국식품영양과학회 학술대회발표집 Vol.2014 No.10