• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제40회 동계학술대회 초록집
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• pp.323-324
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• 2011

현재 많은 blue LED소자의 제작 공정과 소자 표면에 texturing하는 과정이 보고되어 있다. 그 중n층이 위로 올라오는 수직형 LED 구조로 인해 표면 texturing 기술은 빛의 발광 효율을 증가 시킬 수 있는 중요한 기술 중 하나가 되었다. 1 이 연구에서, 우리는 InGaN을 바탕으로 한 LED 소자의 표면 roughening을 건식과 습식 공정을 모두 거치는 과정을 통하여 소자의 발광 효율을 높이는 시도를 하였다. 최근 전도성 물질 기판 위에 증착 되어 있는 수직형 LED 소자 2,3,4는 과거의 사파이어 기판 위에 증착 되어 있는 형태의 LED 소자에 비해 우수한 소자 특성을 보인다. 이는 과거 사파이어 기판을 사용함으로써 낮은 열적 특성과 더불어 전기 정도성에 몇 가지 제약을 초래하게 되었기 때문이다. 반면, 전도성 기판은 LED 구조의 back side ohmic contact을 가능하게 하였고, 더 나은 확산 특성을 보여 주었고 작동 전압 또한 감소 하였다. N층이 위에 있는 수직형 LED 소자는 KrF pulsed excimer laser로 인해 실현 되었다. 이 laser 빛이 투명한 사파이어 기판을 통해 얇은 GaN층에 입사되면, 기판과 GaN가 분리된다. 이 레이저 기술은 laser lift-off(LLO)로 성장된 기판으로부터 LED 구조를 분리하는데 성공하게 하였다. 우리는 건식 식각 공정을 이용하여 n 층이 위에 올라와 있는 구조인 수직형 LED 소자에 roughening을 주고 다시 이 표면에 습식 식각 공정을 적용하여 거친 부분의 거칠기를 또 한번 증가시켰다. 그리고 이 거칠어진 표면은 이 공정이 진행 되기 전의 소자에 비해 빛의 발광 효율이 증가 되었다. 이 두 공정을 포함한 식각 공정은 두 가지 장점이 생겼는데, 한가지는 GaN에서 외부로 방출할 수 있는 표면 지역이 증가되었고, 다른 한가지는 가파른 거칠기 특성으로 인해 critical angle을 증가시킨 것이다.

• 한국농림기상학회지
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• 제22권3호
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• pp.152-163
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• 2020

실제적인 산사태 대응조치 단계 이전에 산사태위험지수를 통하여 산사태 발생 위험도를 모니터링하고 예측하기 위하여, LAMP의 고해상도 강우와 토양수분 예측 자료를 DB화 하고, 산사태 연구자들의 연구대상 지역에 적합한 지도 투영법과 공간해상도로 변환하는 절차를 ArcGIS를 이용하여 마련하였다. 이를 위하여 ERA5 재분석 강수와 농촌진흥청 10m 깊이 토양수분자료를 이용하여 LAMP 모델 강수 및 토양수분 자료를 정량적 그리고 정성적으로 평가하여 모델의 특성을 파악하였다. 또한, LAMP 강우, 토양수분, 증발산 등의 결과 자료를 10m 초고해상도 ArcGIS 포맷 자료로 변환하는 과정을 실무적으로 상세히 기술하여, 국내 지역에서 WRF 모델의 NetCDF 자료를 ArcGIS로 이용자들이 손쉽게 변환할 수 있도록 기술적 편의를 제공하였다.

• 공업화학
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• 제17권6호
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• pp.658-664
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• 2006

$\rho$, $\alpha$-dimethyl benzyl alcohol을 효과적으로 분할하기 위하여 2상 동적 속도론적 광학분할(biphasic dynamic kinetic resolution, DKR)반응을 실시하였다. 라세미화 반응을 위하여 촉매로 산성 제올라이트를 사용하였고 속도론적 광학분할(kinetic resolution, KR)을 위하여 고정화 효소를 촉매로 사용하였다. 유기용매와 물을 용매로 사용하는 이상 DKR 반응에서, acyl donor, 반응온도, 기질의 농도, 두 가지 촉매의 상대적 비율 및 교반속도 등의 공정변수를 변화시켜가면서 DKR반응의 전환율과 생성물의 광학순도에 미치는 영향을 조사하였다. 그 결과, $\rho$, $\alpha$-dimethyl benzyl alcohol의 DKR 반응에서 99% 이상의 광학순도를 가지는 생성물을 최대 88%의 높은 수율로 얻을 수 있었으며, 높은 TON에서도 반응의 효율성이 유지되었고 촉매의 재사용 시에도 지속적인 활성을 나타내었다.

• 보건교육건강증진학회지
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• 제24권2호
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• pp.15-28
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• 2007

Objectives: In this paper, the survey on internet usage patterns of health consumers was conducted and analyzed in order to determine internet health information assessment criteria for providing correct consumer health information on web-sites. Methods: By using a survey questionnaire with 16 questions on general information and 20 questions on internet health information, data were collected from September 16 to 25, 2005 from 476 participants through an internet web site, http://www.hp.go.kr. Frequency analysis, t-test, and multiple regression were used in order to analyze the difference in assessment criteria, factors influencing assessment criteria, factors influencing user satisfaction, etc. Results: General characteristics of the study population were: the persons over age 40 were the smallest age group; women were accounted for 74.2%; and the persons with average income were the largest income group; and the persons with average health status were the largest health group. Most widely used health information were: exercise, disease, and diet, in order. There was significant difference(p=.001) in importance of assessment criteria between the persons in medical institutions and the persons not in medical institutions. There was no significant difference in other assessment criteria. We also found that contents of websites and easy to use were more important factors than elucidation of information providers and information sources including speciality of information in quality assessment criteria of internet health information. Discussion and Conclusion: Results of this paper were compared with the previous studies from the literatures. Contrary to the previous studies in the literature, there was significant difference in importance of assessment criteria between the persons in medical institutions and the persons not in medical institutions. In order to apply the study results to develop health contents for consumer, there is a need for further upgrade the proposed assessment criteria based on expert opinion.

• 한국수소및신에너지학회논문집
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• 제13권3호
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• pp.169-180
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• 2002

Rayleigh scattering and laser induced predissociative fluorescence are used to obtain two-dimensional images of temperature and species concentration in a laminar non-premixed flame of a diluted hydrogen jet. Rayleigh scattering cross-sections are experimentally obtained at 248nm. Planar images of OH and $O_2$ with tunable KrF excimer laser which has a) $0.5cm^{-1}$ linewidth, b) 0.5nm tuning range, c) 150mJ pulse energy, and d) 20ns pulse width are obtained to determine spatial distributions of OH and $O_2$. The technique is based on planar laser induced predissociative fluorescence (PLIPF) in which collisional quenching is almost avoided because of the fast predissociation. Dispersed LIPF spectra of OH and $O_2$ are also measured in a flame in order to confirm the excitation of single vibronic state of OH and $O_2$. OH and $O_2$ are excited on the $P_2$(8) and $Q_1$(11) line of the $A^2{\Sigma}^{+}({\nu}^{'}=3)-X^{2}{\Pi}({\nu}^{''}=o)$ band and R(17) line of the Schumann-Runge band $B^{3}{\Sigma}_{u}{^-}(\nu^{'}=0)-X^{3}{\Sigma}_{g}{^-}({\nu}^{''}=6)$, respectively. Fluorescence spectra of OH and Hot $O_2$ are captured and two-dimensional images of the hydrogen flame field are successfully visualized.

• 가정과삶의질연구
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• 제32권5호
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• pp.15-30
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• 2014

This study aims to analyze what factors are associated with child care accreditation in Chungbuk province. This study examined three questions about which factors influence the accreditation of childcare centers: 1) if they passed the accreditation criteria, 2) the total score on the accreditation criteria, and 3) the domain scores for the six domains of environment, management, process, interaction and teaching, health and nutrition, and safety. The characteristics of 1,212 childcare centers, the independent variables, were commit management, type, specialized service, maximum capacity of children, registration ratio, target age groups of children, duration, and city size. The formal expert committee evaluated objective scores for 952 childcare centers. I derived the data for this study from the i-sarang Childcare Information Portal site (http://info.childcare. go.kr/). Frequency, descriptive statistics, binary logit model, and OLS model analysis were used to examine the accreditation and scores by factors of childcare centers. The findings of the present study are as follows. First, about 80% of the 1,212 childcare centers in Chungbuk province were accredited. Second, the accreditation of the child care center was affected by the specialized service, registration ratio, and duration. Finally, the total score of accredited childcare centers was associated with the maximum capacity of children, registration ratio, and duration. The factors of childcare centers influencing sub-area scores were different by environment, interaction and teaching, health and nutrition, and safety. The present study is important because it offers preliminary data identifying accreditation characteristics that can judge problems related to the quality of service of childcare centers and suggest childcare policy implications.

• KSBB Journal
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• 제20권3호
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• pp.244-249
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• 2005

Kromasil HR100-5CHI-TBB 칼럼을 사용하여 HPLC를 통한 비스테로이드 계통의 진통 및 소염제인 racemic ibuprofen의 분리특성을 연구하였다. 이동상의 조성비 변고에 따른 분리도 (resolution), 이론단수 (number o( theoretical plates), 이론단 높이 (HETP: Height Equivalent to a Theoretical Plate), 용량인자 (capacity factor)를 계산하고, 그 결과 정성분석 기준치 이상의 분리도를 갖고 분리시간을 단축할 수 있는 hexane /t-BME의 조성이 55 / 45일 때 $1\%$의 acetic acid를 첨가했을 때의 용매를 최적의 이동상으로 결정했다. 유속에 따른 칼럼의 효율을 비교하기 위한 실험을 통해 유속의 상승은 칼럼의 효율의 감소를 야기하고, 분리도를 감소시킴을 보였다. PIM (Pulsed Input Method)을 사용하여 분석한 결과 ibuprofen 의 농도가 증가할수록 Langmuir 등온흡착식을 따르는 비선형 거동을 보임을 증명하였고, 그 결과 등온흡착식을 결정하였다. 등온흡착식은 S-form과 R-form의 경우 각각 $C_{S,S}=\frac{1.178C_{M,S}}{1+0.019C_{M,S}},\;C_{S,R}=\frac{1.866C_{M,S}}{1+0.017C_{M,S}}$로 결정하였다.

• 가족자원경영과 정책
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• 제11권4호
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• pp.93-114
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• 2007

The purpose of this study was to analyze the educational program that is offered on the information menu in the homepage (Familynet) of the Healthy Family-Support Center (HFSC) and suggest developmental directions. For this purpose, first, it deduced that the managerial principles of the education program, from related theories, are included in the family-system, family-structure, family-structure analysis, family life-cycle and ecological system theories. Second, it analyzed the educational programs of 44 local centers that are connected to the homepage (familynet.or.kr) of HFSC. Finally, it suggested developmental directions for managerial improvements of educational programs. As a result, the most popular part in the educational program was parent education, especially the visiting-father education program. The number of couple-related education programs were fewer than those for parent education, because it is difficult for couples to be present at the same time. Family and Self-Cognition programs cover insufficient contents in the parent-education program. Though total program in familylife education is quite large, the number of programs in each separate part is far too small for such a wide subject. So, each part in the program should be made more sufficient. Finally, it suggested the development of an evaluation system and a coaching process as special services for families that are in different development stages and have different family experiences, resources, needs and goals.

• Genomics & Informatics
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• 제17권3호
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• pp.26.1-26.12
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• 2019

Identification of fusion gene is of prominent importance in cancer research field because of their potential as carcinogenic drivers. RNA sequencing (RNA-Seq) data have been the most useful source for identification of fusion transcripts. Although a number of algorithms have been developed thus far, most programs produce too many false-positives, thus making experimental confirmation almost impossible. We still lack a reliable program that achieves high precision with reasonable recall rate. Here, we present FusionScan, a highly optimized tool for predicting fusion transcripts from RNA-Seq data. We specifically search for split reads composed of intact exons at the fusion boundaries. Using 269 known fusion cases as the reference, we have implemented various mapping and filtering strategies to remove false-positives without discarding genuine fusions. In the performance test using three cell line datasets with validated fusion cases (NCI-H660, K562, and MCF-7), FusionScan outperformed other existing programs by a considerable margin, achieving the precision and recall rates of 60% and 79%, respectively. Simulation test also demonstrated that FusionScan recovered most of true positives without producing an overwhelming number of false-positives regardless of sequencing depth and read length. The computation time was comparable to other leading tools. We also provide several curative means to help users investigate the details of fusion candidates easily. We believe that FusionScan would be a reliable, efficient and convenient program for detecting fusion transcripts that meet the requirements in the clinical and experimental community. FusionScan is freely available at http://fusionscan.ewha.ac.kr/.

• 한국원자력학회:학술대회논문집
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• 한국원자력학회 1995년도 추계학술발표회논문집(2)
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• pp.707-712
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• 1995

Grain boundary diffusion plays significant role in the fission gas release, which is one of the crucial processes dominating nuclear fuel performance. Gaseous fission products such as Xe and Kr generated inside fuel pellet have to diffuse in the lattice and in the grain boundary before they reach open space in the fuel rod. In the mean time, the grains in the fuel pellet grow and shrink according to grain growth kinetics, especially at elevated temperature at which nuclear reactors are operating. Thus the boundary movement ascribed to the grain growth greatly influences the fission gas release rate by lengthening or shortening the lattice diffusion distance, which is the rate limiting step. Sweeping fission gases by the moving boundary contributes to the increment of the fission gas release as well. Lattice and grain boundary diffusion processes in the fission gas release can be studied by 'tracer diffusion' technique, by which grain boundary diffusion can be estimated and used directly for low burn-up fission gas release analysis. However, even for tracer diffusion analysis, taking both the intragranular grain growth and the diffusion processes simultaneously into consideration is not easy. Only a few models accounting for the both processes are available and mostly handle them numerically. Numerical solutions are limited in the practical use. Here in this paper, an approximate analytical solution of the lattice and stationary grain boundary diffusion in a polycrystalline solid is developed for the tracer diffusion techniques. This short closed-form solution is compared to available exact and numerical solutions and turns out to be acceptably accurate. It can be applied to the theoretical modeling and the experimental analysis, especially PIE (post irradiation examination), of low burn up fission. gas release.