고주파 때려내기법에 의한 질화알루미늄 박막의 제작과 특성

정성훈,김영호,문동찬,김선태 ( Sung Hoon Chung,Young Ho Kim,Dong Chan Moon,Seon Tai Kim ) 한국전기전자재료학회 1997 전기전자재료학회논문지 Vol.10 No.7

HVPE 에 의해 성장된 Zn가 첨가된 GaN 의 특성

정성훈,김우람,홍필영,문동찬,김선태 ( Sung Hoon Chung,Woo Ram Kim,Pil Young Hong,Dong Chan Moon,Seon Tae Kim ) 한국전기전자재료학회 1997 한국전기전자재료학회 추계학술대회논문집 Vol.1997 No.1

HVPE 에 의한 불순물이 첨가된 GaN 박막의 제작

정성훈,송복식,문동찬,김선태 ( Sung Hoon Chung,Bok Sik Song,Dong Chan Moon,Sun Tae Kim ) 한국전기전자재료학회 1997 한국전기전자재료학회 춘계학술대회논문집 Vol.1997 No.0

소아 Kikuchi 병의 임상 양상

정성훈,박성신,이규하,송준혁,한미영,최용묵,차성호,박용구,Chung, Sunghoon,Park, Sungsin,Lee, Kyuha,Song, Junhyuk,Han, Miyoung,Choi, Yongmook,Cha, Sungho,Park, Yongkoo 대한소아감염학회 2007 Pediatric Infection and Vaccine Vol.14 No.2

목 적 : Kikuchi 병은 고열을 동반한 양성 림프절 비대를 특징으로 하는 아급성 괴사성 림프절염이다. 주로 젊은 여성에게 발생하며 소아에 있어 드물게 보고되고 있다. 병인으로는 바이러스와 연관성, 자가 면역기전 등이 제시되고 있으나 정확히 밝혀지지 않은 상태이다. 최근 저자들은 소아에서 발생한 괴사성 림프절염 5례를 경험하였기에 소아에 있어 Kikuchi 병의 임상적 고찰을 하였다. 방 법 : 2001년 1월부터 2006년 6월까지 경희대학교 소아과에 Kikuchi 병으로 진단 받은 환아 5명을 의무기록을 통해 발생 연령, 성별비, 계절별 발생빈도, 임상증상, 과거력, 검사 소견, 림프절의 발생 부위 및 크기, 방사선학적 소견 등을 조사하였다. 결 과 : 남아가 2명, 여아가 3명이었으며, 평균 연령은 9년 9개월(8년 2개월-12년 6개월)이었다. 주된 증상은 지속되는 발열과 림프선 비대로 병원을 방문하였다. 모든 환자는 항생제 치료를 받았으며, 2명의 환자에게서 발진이 발생하였다. 1례에서 초음파 검사상 Kikuchi 병이 의심되는 괴사성 변화가 관찰되었다. 3례에서 추가적으로 컴퓨터 단층촬영을 실시하였다. 입원 후 절제 생검할 때까지 소요된 시간은 10.2일(7-15일)이었다. 5례 모두 림프절 절제 생검 후 조직 검사상 괴사성 림프절염으로 확진하였다. 결 론 : Kikuchi 병은 진단 전에 불필요한 검사와 항생제 치료를 하며 이로 인해 입원 기간도 길어진다. 이에 저자들은 소아에 있어 Kikuchi 병의 임상 양상을 고찰하였다. Purpose : Kikuchi disease is a subacute necrotizing lymphadenitis characterized by fever, cervical lymphadenopathy and benign self-limiting course in young women especially, but rare in children. Their etiopathology is still unknown, but involved viruses and autoimmune mechanism were proposed. We investigated the clinical and laboratory characteristics of Kikuchi disease in children. Methods : Five patients were diagnosed of Kikuchi disease from January 2001 to June 2006 in Kyunghee University Hospital. We reviewed their medical records retrospectively and analyzed clinical and laboratory findings. Results : The mean age of 5 patients (male to female ratio; 2:3) was 9 yr 9 mon(range: 8 yr 2 mon-12 yr 6 mon). The chief complaints were sustained fever and cervical lymph node that was unilateral, tender and swollen. All patients were treated with antibiotics before diagnosis was made, and rash developed in 2 patients. One patient showed necrotic change in ultrasound with which we suspected Kikuchi disease. Three patients were examined by CT scan additionally. The interval between admission and cervical lymph node excisional biopsy ranged from 6 days to 15 days, and mean period was 9.6 days. All pathological findings were compatible to necrotizing lymphandenitis. Conclusion : Unnecessary laboratory and imaging studies, and treatment with antibiotics tend to be done before making diagnosis, and that caused prolonged hospitalization. Therefore we studied the clinical and laboratory characteristics of Kikuchi disease in children.

유리선량계를 이용한 투과선량 기반 환자선량 평가 시스템 개발을 위한 가능성 연구

정성훈,윤명근,김동욱,정원규,정미주,최상현,Jeong, Seonghoon,Yoon, Myonggeun,Kim, Dong Wook,Chung, Weon Kuu,Chung, Mijoo,Choi, Sang Hyoun 한국의학물리학회 2015 의학물리 Vol.26 No.4

방사선치료는 수술, 항암치료와 함께 암의 3대 치료방법으로써 많은 암환자들이 방사선치료를 받게 된다. 최대한 많은 방사선을 암에 집중시키고 최대한 적은 방사선을 주변 정상 조직에 가해주기 위해 치료 전 치료계획을 철저히 세우고 품질 관리를 시행하지만 방사선치료가 잘못 시행되어 의도치 않은 방사선이 환자에게 전달되는 의료사고가 발생하기도 한다. 이를 해결하기 위해 환자 내부의 선량을 검증하기 위한 방법을 투과선량 측정을 통한 환자 내부선량의 역추정 방법이 제시되고 있다. 본 연구에서 제시한 투과선량을 이용한 환자선량 계산 방법을 거리역자승법칙, 심부선량백분율, scatter factor를 이용한 방법으로써 실제 환자 선량 평가 가능성에 대해 균질한 물등가 팬텀을 이용한 연구이다. 투과선량에 대한 이온함과 유리선량계의 교정 결과 유리선량계의 신호값이 이온함으로 측정한 선량값에 비해 6 MV에서 0.824, 10 MV에서 0.736배인 것으로 나타났고 scatter factor는 평균적으로 1.4정도인 것으로 확인되었다. 심부선량백분율 데이터를 사용하기 위해 Mayneord F factor를 적용하였으며 위의 정보들을 이용하여 균질한 팬텀에서 알고리즘을 검증한 결과 최대 오차 약 1.65%로 계산이 정확하게 실시됨을 확인하였다. As radiation therapy is one of three major cancer treatment methods, many cancer patients get radiation therapy. To exposure as much radiation to cancer while normal tissues near tumor get little radiation, medical physicists make a radiotherapy plan treatment and perform quality assurance before patient treatment. Despite these efforts, unintended medical accidents can occur by some errors. In order to solve the problem, patient internal dose reconstruction methods by measuring transit dose are suggested. As feasibility study for development of patient dose verification system, inverse square law, percentage depth dose and scatter factor are used to calculate dose in the water-equivalent homogeneous phantom. As a calibration results of ionization chamber and glass dosimeter to transit radiation, signals of glass dosimeter are 0.824 times at 6 MV and 0.736 times at 10 MV compared to dose measured by ionization chamber. Average scatter factor is 1.4 and Mayneord F factor was used to apply percentage depth dose data. When we verified the algorithm using the water-equivalent homogeneous phantom, maximum error was 1.65%.

반복적인 폐구균 감염을 보인8세 남아와 친형에서의 범저감마글로불린혈증

정성훈,안용주,김수연,조병수,김성도,Chung, Sung-Hoon,Ahn, Yong-Joo,Kim, Su-Yeon,Cho, Byoung-Soo,Kim, Sung-Do 대한소아감염학회 2007 Pediatric Infection and Vaccine Vol.14 No.1

범저감마글로불린혈증은 X 염색체에 의해 유전되는 질환으로 주로 1세 이전에 진단이 가능하지만, 진단이 늦어질 경우 반복된 감염 및 중증 감염으로 인한 심각한 후유증을 남길 수 있으므로 조기 진단과 치료가 매우 중요하다. 증상이 다양하게 나타날 수 있으므로 진단을 위한 각별한 주의가 요구된다. 저자들은 반복적이고 심각한 감염의 병력에도 8세가 돼서야 범저감마글로불린혈증 진단을 받은 환아와 그로 인해 함께 진단 받은 친형의 사례를 경험하였기에 보고하는 바이다. Patients with primary immunodeficiencies often have symptoms of their disease for months or years before diagnosis and treatment. This is partly because these disorders are relatively uncommon and the infections typical of immunodeficienciey, for example otitis, sinusitis, and pneumonia, are common. We report a case of agammaglobulinemia in an 8-year-old boy with recurrent and severe infection. He was first seen in our hospital for bacterial meningitis in 2006. His immune status revealed panhypogammaglobulinemia and deficiency in mature B lymphocyte. His elder brother also showed deficiency in mature B lymphocyte but mild hypogammaglobulinemia. Some X-linked agammaglobulinemia (XLA) cases may remain undiagnosed because they only show mild hypogammaglobulinemia and they lack repeated infections in childhood.

악골에 발생한 양성 치성종양의 임상 및 병리조직학적 연구

정성훈(Sung Hoon Chung),이의웅(Eui Wung Lee) 대한구강악안면외과학회 1991 대한구강악안면외과학회지 Vol.17 No.2

The author studied and analyzed on the 56 cases of benign oodontogenic tumor in the jaws which had been diagnosed with biopsy for the period from Jan 1980 to June 1990. in the Deparment of Oral and Maxillofacial surgery, Yonsei Dental hospital. This study contained the clinicostatiscal analysis of the frequency in relation to sex, age, location, chief complaints, duration, radiographic findings, histopathilogic findings and treatment methods. the result of this study were as foollows : 1. Benign odontogenic tumors of 56 cases disclosed 43 cases(76%) of ameloblastomas(28 cases, 50%), odontomas(15 cases, 26%), and other 6 types lesions(13 cases, 24%). 2. Benign odontogenic tumors occured mainly in the first and second decades(61%), male to female ratio oof the study being 1m5:1. Also the majority of cases occured in the mandible than in the maxilla(3:1). 3. In ameloblastoma 1) total 28 cases(50 %) of ameloblastoma occured in the average age of 35.8 years and had a 3:1 male predominance, mainly in the first, second and third decades(19 cases, 68%). The majority of the cases occured in the mandible, especially 14 cases(50%) in the body ramus-angle and body-angle-r4amus-coronoid process. The most common complaint was the swelling without pain(13 cases, 46). As regards duration, 16 cases(57%) was less than 1 year. 2) Radiographically, the unilocular(15 cases, 54%) annd multilocular lesions(13 cases, 46%) were similar distribution, 18 cases(64%) showed the apparent root resorption. 3) histologically, plexiform type was predominantly(10 cases), most of plexiform type was found in the young ages, radiographically it was unilocular type. 4) Radical resection was performed in 12 cases(58%). 6 cases recurredc after surgery and matastasis was absent. 4. In odontoma 1) Total 15 case(26%) of odontoma occured in the less than 30 years of age, the average age was 15.3 years, and sex distribution was not remarkable. The incidence was similar between maxilla and mandible, but more common in the premaxilla, posterior mandible. The most common chief complaint was the delayed eruption of tooth(5 cases, 33%) and followed by the routine radiographic examination(4 cases, 27%). The 8 cases(53%) were of complex type and 7 cases(47%) were of compound type. 5. 6 types of other benign odontogenic tumor, occured in the first and second decades(10 cases, 77%) and shwed similar sexual distribution. Also the incidence was similar beteen maxilla and mandible, but AOT was presented only in the maxilla and odontogenic myxima in the mandible.

폐종괴에서 경피적 자동생검의 유용성

정성훈 ( Sung Hoon Chung ),김형진 ( Hyung Jin Kim ),황영실 ( Young Sil Hwang ),유진종 ( Jin Jong You ),김재수 ( Jae Soo Kim ) 대한결핵 및 호흡기학회 1997 Tuberculosis and Respiratory Diseases Vol.44 No.5

정보기술 혁신이 기업 가치에 미치는 영향: 정보기술 특허를 중심으로

정성훈 ( Sunghun Chung ),김기민 ( Kimin Kim ) 한국지식경영학회 2016 지식경영연구 Vol.17 No.3

The recent patent wars in the information technology (IT) industry demonstrate the strategic importance of IT patents in the industry. In this paper, we adopt the lens of real options to study the value of IT patents for IT firms. Specifically, we examine the relationship between IT patents and firms’ market performance. We also consider the moderating effect of the innovation orientation of firms’ patent portfolios (exploitative vs. explorative). Based on a large panel dataset consisting of 697 firms in US IT industries, our results suggest that the impact of IT patents on firm value (as measured by Tobin’s q) is positive and significant. Further, we find that this impact varies, depending on the innovation orientation of firms’ patent portfolios. IT patent portfolios with higher levels of an exploitative orientation are associated with higher firm value, compared to those with a lower exploitative orientation. This study highlights the value of employing real options theory as the underlying mechanism in understanding the impact of patents on firm valuation. Future researchers can adopt the real options lens to identify and empirically examine the role of other factors that may affect the value of patents and other investments exhibiting real option characteristics. While our paper answers some questions about the value of patents in the IT industry, it also raises a number of additional new questions. As such, we hope that it will generate more research on this important topic.

개선된 ESPRIT 알고리즘을 이용한 퍼진 신호의 신호도착방향 추정

정성훈(Sung-Hoon Chung),이동욱(Dong-Wook Lee) 대한전기학회 1999 대한전기학회 학술대회 논문집 Vol.1999 No.11