수필 : 고향에 다녀와서

한동희 평화문제연구소 1986 통일한국 Vol.34 No.-

돌발성 난청의 원인적 인자가 청력개선 예후에 미치는 영향

한동희,김형종 대한이비인후과학회 2002 대한이비인후과학회지 두경부외과학 Vol.45 No.10

Background and Objectives:There are lots of debates regarding the prognostic factors in sudden deafness patients. The aim of this study is to identify prognostic factors that might be asociated with the degre of hearing recovery from sudden deafness. Materials and Method:We reviewed the records of 110 patients who were admitted for treatment betwen 1999 and 2001 under the initial diagnosis of idiopathic sudden hearing loss. Patients were clasified into following subgroups based on the data of our own diagnostic protocol, including history taking, physical examination and laboratory tests:cardiovascular hematologic group, infectious group, metabolic group, imunologic group, cochlear neurologic group, and the other group. Results:Pa-patients. Patients with metabolic factors showed higher recovery rate than those with other factors. Conclusion:These results sugest that cardiovascular hematologic factors and cochlear neurologic factors might be most significantly related with prog-nosis in sudden deafness patients. (Korean J Otolaryngol 2002;45:936-41)

차량 주행상태를 고려한 차량 배출가스 산정 모형 구축

한동희,이영인,장현호 대한교통학회 2011 대한교통학회지 Vol.29 No.5

Traffic signal is one of the major factors that affect the amount of vehicle emissions on urban highway. The amount of vehicle emissions in urban area is highly affected by the vehicle’s cruising speeds heavily influenced by the traffic signal lighting conditions. It was attempted in this study to trace the changing patterns of the vehicle emissions by collecting the emission data from a set of simulation studies and by categorizing vehicle cruising conditions into four different groups: idling, acceleration, deceleration, and running at a constant speed. Authors propose a simple emission model prepared based on Kinematic theory. The validation test results showed that the amount of the emission estimated by the proposed model was relatively satisfactory compared to the one of the existing model employing the average speed data only as the determinant. 대기오염물질과 온실가스가 주는 폐해는 점차 심각한 수준으로 발전하고 있는 상황에서 자동차에 의한 배출가스가 대표적인 배출원의 하나로 손꼽히고 있다. 교통부문에 있어서는 교통운영전략 등에 의해 배출가스량을 억제 및 관리할 수 있는 방법론에 대한 연구가 필요한 상황이나 아직까지 차량의 운행행태 즉 가속, 감속, 정지 시 등에 따른 배출량을 산정할 수 있는 모형에 대한 연구는 미미한 수준이다. 본 연구에서는 신호교차로와 같은 도로를 주행하는 차량이 가속, 감속 정지 하면서 배출하는 배출가스량을 산정할 수 있는 모형을 구축하였으며 이를 위하여 차량 실험을 기반으로 배출량표를 작성하고 차량의 움직임을 운동학적 접근법으로 분석하여 모형을 구축하였다. 최종적으로는 미시적 시뮬레이터와 배출표를 이용하여 가장 현실적인 배출량 산정체계를 구축하여 모형을 검증, 평가하였다. 평가 결과 기존의 평균주행속도를 이용한 배출모형 보다 상대적으로 정확한 배출량을 산정하는 것으로 분석되었다.

Assessment of Coronary Artery Calcium Scoring for Statin Treatment Strategy according to ACC/AHA Guidelines in Asymptomatic Korean Adults

한동희,장혁재,Briain O Hartaigh,이지현,Asim Rizvi,박효은,최수연,성지동 연세대학교의과대학 2017 Yonsei medical journal Vol.58 No.1

Purpose: The 2013 American College of Cardiology (ACC)/American Heart Association (AHA) cholesterol management guidelinesadvocate the use of statin treatment for prevention of cardiovascular disease. We aimed to assess the usefulness of coronary artery calcium (CAC) for stratifying potential candidates of statin use among asymptomatic Korean individuals. Materials and Methods: A total of 31375 subjects who underwent CAC scoring as part of a general health examination were enrolledin the current study. Statin eligibility was categorized as statin recommended (SR), considered (SC), and not recommended(SN) according to ACC/AHA guidelines. Cox regression analysis was employed to estimate hazard ratios (HR) with 95% confidentialintervals (CI) after stratifying the subjects according to CAC scores of 0, 1–100, and >100. Number needed to treat (NNT) to prevent one mortality event during study follow up was calculated for each group. Results: Mean age was 54.4±7.5 years, and 76.3% were male. During a 5-year median follow-up (interquartile range; 3–7), there were 251 (0.8%) deaths from all-causes. A CAC >100 was independently associated with mortality across each statin group after adjusting for cardiac risk factors (e.g., SR: HR, 1.60; 95% CI, 1.07–2.38; SC: HR, 2.98; 95% CI, 1.09–8.13, and SN: HR, 3.14; 95% CI, 1.08–9.17). Notably, patients with CAC >100 displayed a lower NNT in comparison to the absence of CAC or CAC 1–100 in SC and SN groups. Conclusion: In Korean asymptomatic individuals, CAC scoring might prove useful for reclassifying patient eligibility for receiving statin therapy based on updated 2013 ACC/AHA guidelines.

송배전용 Composite Insulator의 개발동향 및 특성

한동희,황석중,박완기,이철호 한국전기전자재료학회 1998 전기전자재료 Vol.11 No.3

소형 감마카메라에서 확산형 조준기의 구멍 형태 및 배열에 따른 성능평가

한동희,원종훈,백철하 한국물리학회 2020 New Physics: Sae Mulli Vol.70 No.10

For overcoming the drawbacks of pinhole collimators, which are used to detect a wide field of view, compact diverging collimators using metal-based precision machining have recently been drawing attention in the 3D printer field. Thus, we evaluated the performances of diverging collimators among the square, circular and hexagonal holes, as well as the arrangements of the GAGG crystals. The GATE code and the STL file were used, as was a 99mTc point source. The total area and the height of the collimator were set at 25.8 × 25.8 mm2 and 15 mm respectively. While the spatial resolution for all holes was relatively constant within a low error, the sensitivity for the square holes was 37.3% better than that for circular boles and 52.2% better than that for hexagonal holes, Similar results were obtained when the source was moved to the X-axis. Also, if the arrangement of crystals matched the type of the holes in the collimator, the spatial resolution was slightly better, confirming that the higher the degree of matching the hole, the better the performance. 최근 3D 프린터에서 금속 재질의 정밀 가공기술을 이용한 소형 확산형 조준기에 대한 연구가 활발히진행되고 있다. 이에 본 연구에서는 확산형 조준기의 구멍 형태가 사각형, 원형, 육각형일 때와 섬광체의배열 형태에 따른 민감도와 공간분해능의 차이를 평가하고자 하였다. 이를 위해 몬테카를로 시뮬레이션도구인 GATE와 STL 파일을 이용하였고, 점선원 99mTc(140 keV)과 조준기의 전체 면적, 높이는 각각25.8 × 25.8 mm2, 15 mm로 동일하게 설계하였다. 모든 구멍에서 공간분해능은 작은 오차 내 범위로비교적 일정했던 반면 민감도는 사각형이 원형 대비 37.3%, 육각형 대비 52.2% 우수했으며, 이는 선원이가장자리로 이동했을 때도 유사하였다. 또한, 섬광체의 배열이 조준기의 구멍 형태와 일치했을 경우 공간분해능은 개선되었고, 이를 통해 조준기의 구멍과 일치되는 정도가 높을수록 성능이 개선됨을 확인하였다.

스티븐 히스의 ‘원근법적 시선’에 대하여

한동희 한국영화학회 2005 한국영화학회 학술발표대회 논문집 Vol.- No.-

실리콘계 절연재료

한동희,강동칠,박효열 한국전기전자재료학회 2000 전기전자재료 Vol.13 No.2

기업 이러닝 학습에서의 학습 성과에 영향을 미치는 학습 행태 요인분석 - 우수 학습자와 전체 학습자 로그 분석 비교를 중심으로

한동희,전병준 한국자료분석학회 2015 Journal of the Korean Data Analysis Society Vol.17 No.2

본 연구는 32개월 동안 직장인들의 이러닝 로그를 분석함으로써 이러닝 학습 성과에 영향을 미치는 요인으로서 학습 행태에 초점을 맞추고, 기업체(대기업, 외국계, 공기업)분석을 통하여 학습 행태 요인에 대한 기술 통계, 집단별 차이, 상관관계 등을 살펴보고자 한다. 이를 위해 국내 최대 이러닝 전문 위탁 기업인 C社의 학습자 중 전체 학습자 36,193명과 이 중 상위 1%에 해당하는 우수 학습자 300명(상위 1%는 361명이나 학습자 정보 공개가 불가능한 61명을 제외)을 선정하여 연구대상으로 선정하고, 학습한 시각에 대한 로그를 학습객체 단위로 시각별, 요일별로 분석하였으며 결과는 다음과 같다. 첫째, 학습자들이 집중적으로 학습에 참여하는 시간대가 존재하였다. 즉 출근 시간 전후(8~9시)의 접속률이 가장 높으며, 점심시간(12~13시), 퇴근시간 전후(17~18시)에도 접속 빈도가 높아지는 것을 발견하였다. 둘째, 기업 유형별로 학습 패턴 및 성취도의 차이가 나타났다. 즉 대기업, 공기업, 외국계 기업 세 집단 중 총 학습시간 및 접속 횟수에서 공기업이 가장 높았으며, 그만큼 학습 성취도(수료율, 성적) 또한 높은 것으로 나타났다. 셋째, 학습 참여도와 학습 성취도는 유의미한 상관관계가 없는 것으로 나타났다. This study focuses on learning behaviors as a factor affecting e-learning performance by analyzing office worker's e-learning log-ons for 32 months and looks into technical statistics, differences by group, correlation and etc. by analyzing companies (large companies, foreign companies, public companies). For this, a total of 36,193 learners and 300 outstanding learners (though the upper 1% is 361, 61 are excluded because their information is not available) of C company, which is the biggest e-learning contracting company, were selected as research subjects and each of their log-ons for learning was analyzed by hour and day, whose result is as follows. First, there exists the time zone in which they extensively join learning. That is, their log-on is the highest before and after they go to work (8~9) followed by lunch hours (12~13), and before and after they finish work (17~18). Second, there are differences by company type in learning pattern and accomplishment. That is, among the three groups of large, public and foreign companies, public companies have the highest number of log-ons and learning hours. And their learning accomplishment (graduation ratio and scores) is higher accordingly. Third, no significant correlation is found in learning participation and accomplishment level.

Development of a diverging collimator for environmental radiation monitoring in the industrial fields

한동희,이승재,김장오,권다은,이학재,백철하 한국원자력학회 2022 Nuclear Engineering and Technology Vol.54 No.12

Environmental radiation monitoring is required to protect from the effects of radiation in industrial fields such as nuclear power plant (NPP) monitoring, and various gamma camera systems are being developed. The purpose of this study is to optimize parameters of a diverging collimator composed of pure tungsten for compactness and lightness through Monte Carlo simulation. We conducted the performance evaluation based on spatial resolution and signal-to-noise ratio for point source and obtained gamma images and profiles. As a result, optimization was determined at a collimator height of 60.0 mm, a hole size of 1.5 mm, and a septal thickness of 1.0 mm. Also, the full-width-at-half-maximum was 3.5 mm and the signal-to-noise ratio was 53.5. This study proposes a compact 45 diverging collimator structure that can quickly and accurately identify the location of the source for radiation monitoring.