• 대한치과교정학회지
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• 제36권6호
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• pp.402-411
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• 2006

측두하악장애 환자 중 하악과두의 퇴행성 골 변화를 보이는 환자의 분포와 임상적 특징을 규명하고자 측두하악장애로 진단받은 6,070명의 환자들을 대상으로 연구를 시행하였다. 환자들의 초진 시 파노라마와 TMJ 파노라마 사진을 관찰하여 하악과두의 퇴행성 골 변화 유무를 기준으로 환자들을 퇴행성 골 변화를 보이는 군(DJD군)과 골 변화를 보이지 않는 군(non-DJD군)으로 나누고, 환자들의 초진 의무기록을 바탕으로 두 군 간의 특징을 비교, 분석하였으며, 각종 변수들이 DJD 발병에 미치는 상대적 위험성을 측정하기 위하여 로지스틱 회귀분석을 시행하였다. 연구결과 전체 환자 중 DJD군에 속한 환자는 31.7%였고, non-DJD군에 속하는 환자는 68.3%였다. DJD군은 성별에 따라 다른 분포를 보여 남자보다 여자의 이환율이 높았고, 10대와 20대에서 가장 높은 분포를 보였다. 환자의 내원 주소 중에서는 전치부 개방교합, 턱의 후퇴감, 안모 비대칭, 개구장애를 주소로 내원한 환자가 다른 주소로 내원한 환자들에 비해 DJD를 보일 위험성이 높았으며, 교정치료 경력이나 중심 위-중심교합위 변위 그리고 염발음을 보이는 환자도 DJD군에 속할 위험성이 큰 것으로 나타났다. 따라서 측두하악장애를 가진 환자 중 30세 이하의 여성이 위와 같은 임상적 특징을 보이는 경우, 교정치료를 계획할 때 DJD에 이환 되었을 가능성에 대하여 충분히 주의를 기울여야 할 것으로 생각된다.

• 한국콘텐츠학회논문지
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• 제8권10호
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• pp.54-63
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• 2008

모바일 환경에서 컴퓨터의 성능 향상으로 멀티미디어 플레이어에 대한 사용자 요구로 하나의 동영상 재생기(Media Player)에서 여러 개의 동영상을 동시에 실행시킬 수 있는 복수 동영상 재생기가 일반화 것으로 본다. 현재로는 단일 동영상 재생에서 사용한 방법을 그대로 사용한 복수 동영상 재생을 지원하는 제품이 나왔으나, 그로 인한 문제점은 해결하지 못하고 있다. 본 논문에서는 단일 동영상 재생에서 사용되어지는 방법들을 복수 동영상의 재생 시에 적용할 경우에 생기는 문제점들 즉, 복수 동영상 재생시의 깜빡임 현상, 재생 우선순위 처리 그리고 반투명 처리 문제와 여러 개의 동영상을 재생할 경우에 가장 큰 문제점으로 공간 연출 지원이 이루어지지 않는다는 점을 인식하고, 오버랩핑(overlapping)과 오버레이 (overlay)기법을 사용하는 복수 동영상의 공간 재생기를 설계 및 구현하였다.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.402.1-402.1
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• 2016

The performance of solid oxide fuel cells (SOFCs) is directly related to the electrocatalytic activity of composite electrodes in which triple phase boundaries (TPBs) of metallic catalyst, oxygen ion conducting support, and gas should be three-dimensionally maximized. The distribution morphology of catalytic nanoparticle dispersed on external surfaces is of key importance for maximized TPBs. Herein in situ grown nickel nanoparticle onto the surface of fluorite oxide is demonstrated employing gadolium-nickel co-doped ceria ($Gd0.2-xNixCe0.8O2-{\delta}$, GNDC) by reductive annealing. GNDC powders were synthesized via a Pechini-type sol-gel process while maximum doping ratio of Ni into the cerium oxide was defined by X-ray diffraction. Subsequently, NiO-GNDC composite were screen printed on the both sides of yttrium-stabilized zirconia (YSZ) pellet to fabricate the symmetrical half cells. Electrochemical impedance spectroscopy (EIS) showed that the polarization resistance was decreased when it was compared to conventional Ni-GDC anode and this effect became greater at lower temperature. Ex situ microstructural analysis using scanning electron microscopy after the reductive annealing exhibited the exsolution of Ni nanoparticles on the fluorite phases. The influence of Ni contents in GNDC on polarization characteristics of anodes were examined by EIS under H2/H2O atmosphere. Finally, the addition of optimized GNDC into the anode functional layer (AFL) dramatically enhanced cell performance of anode-supported coin cells.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 춘계학술대회 논문집 센서 박막재료 반도체재료 기술교육
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• pp.55-61
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• 2002

Ultra-fine particles of $SnO_{2}$ was synthersized by the sol-gel powder processing using tin(II) chloride dihydrate$(SnCl_{2}{\cdot}2H_{2}O)$ and ethanol$(C_{2}H_{5}OH)$ as raw materials. Gel powders can be obtained by drying of sol at $120^{\circ}C$ after aging 72hrs and 168hrs. The amount of $SnO_{2}$ phase was increased with temperature because of the evaporation of volatile components, and the creation of $SnO_{2}$ phase was almost done by the heat treatment at $700^{\circ}C/30min$ The grain sizes after firing are about 20-30nm, and it showed the narrow distribution of grain size. The specimens to measure electrical properties were fabricated by the thick film screen printing technique on the alumina substrates. The conductance of $SnO_{2}$ was increased with temperature up to $380^{\circ}C$ by the typical conduction mechanism of semiconducting ceramics. There was a region of constant conductance between about $200^{\circ}C$ and $380^{\circ}C$ due to the increment of electron concentration with temperature and the annihilation of conduction carriers by the absorption and electron trapped-ionization of oxygen on the surface of $SnO_{2}$, It was finally showed the intrinsic behaviors above $450^{\circ}C$. The sensing properties of response time, recovery, and sensitivity of CO were improved with aging time.

• 대한간호학회지
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• 제39권5호
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• pp.641-650
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• 2009

Purpose: This study was done to examine the difference in cancer screening with mammography and Papanicolaou smear according to Body Mass Index (BMI). Methods: The participants in this study were 5,912 women ages 40 to 69 yr, selected from the Korean Genomic Regional Cohort in Kangwon province. Mammography and Papanicolaou smear were assessed by questionnaire and body weight (kg) and height (m) measured to calculate BMI. Results: The distribution of BMI was as follows: low weight (1.5%), normal weight (31.1%), over weight (24.6%), mildly obese (36.4%) and severely obese (6.3%). After adjusting for age, education and monthly income, compared with normal weight women, overweight women (odds ratio [OR]=1.283, 95% confidence interval [CI]=1.089-1.513) and mildly obese women (OR=1.214, 95% CI=1.048-1.406) were less likely to have had mammography. In contrast to mammography, cancer screening with Papanicolaou smear was not significantly different by BMI. Conclusion: Obese women in rural areas are less likely to screen for breast cancer by using mammography than non obese women. To ensure regular screening for breast cancer, health care providers need to give scrupulous care to obese women and remove barriers originated from obesity. Also, educational and clinical implications are considered to increase the Papanicolaou smear rate.

• Nuclear Engineering and Technology
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• 제38권1호
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• pp.93-98
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• 2006

The radial uniformity of neutron irradiation in silicon ingots for neutron transmutation doping (NTD) at HANARO is examined by both calculations and measurements. HANARO has two NTD holes named NTD1 and NTD2. We have been using the NTD2 hole for 5 in. NTD commercial service, and we intend to use two holes for 6 in. NTD. The objective of this study is to predict the radial uniformity of 6 in. NTD at the two holes. The radial neutron flux distributions inside single crystal and noncrystal silicon loaded at the NTD2 hole are calculated by the VENTURE code. For NTD1, the radial distributions of the reaction rate for a 6 in. NTD with a neutron screen are calculated by MCNP, and measured by gold wire activation. The results of the measurements are compared with those of the calculations. From the VENTURE calculation, it is confirmed that the neutron flux distribution in the single crystal silicon is much flatter than that in the non-crystal silicon. The non-uniformities of the measurements for radial neutron irradiation are slightly larger than those of the calculations. However, excluding local dips in the measurements, the overall trends of the distributions are similar. The radial resistivity gradient (RRG) for a 5 in. silicon ingot is estimated to be about $1.5\%$. For a 6 in. ingot, the RRG of a silicon ingot irradiated at HANARO is predicted to be about $2.1\%$. Also, from the experimental results, we expect that the RRG would not be larger than $4.4\%$.

• 식물병연구
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• 제20권4호
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• pp.295-298
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• 2014

참나무 시들음병(병원균 Raffaelea quercus-mongolicae)은 2004년 국내에 처음 발견되어 그 피해가 증가하고 있는 추세이다. 이번 연구에서는 참나무 시들음병 방제를 위한 나무주사용 살균제를 선발하기 위해 실내시험과 포장시험을 실시하였다. 실내검정에서는 10종의 살균제와 1종의 항생제를 이용하여 국내균주 R. quercus-mongolicae와 일본균주 R. quercivora에 대한 생육억제효과를 조사하였다. 국내균주에 대해서는 chlorothalonil, benomyl, propiconazole 순으로 생육억제효과가 높게 나타났으며, 일본균주에 대해서는 propiconazole, benomyl, bitertanol 순으로 나타났다. 국내균주와 일본균주에 대하여 실내 항균효과가 우수하였던 약제 중 침투이행성이 우수한 propiconazole을 이용하여 약제방제 포장시험을 실시하였다. 그 결과 나무주사 처리 당해 연도 방제효과는 87.5%, 처리 다음 연도 방제효과는 66.7%까지 나타나 약제처리 효과는 적어도 1년 이상이었다.

• Journal of Animal Science and Technology
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• 제54권6호
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• pp.463-469
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• 2012

This study utilized a standardization and cluster analysis technique for the selection and classification of beneficial bacteria. A set of synthetic data consisting of 100 individual variables with three characteristics was created for analysis. The three characteristics assigned to each independent variable were designated to have different numeric scales, averages, and standard deviations. The variables were bacterial isolates at random, and the three characteristics were fermentation products, including cell yield, antioxidant activity of culture, and enzyme production. A standardization method utilizing a standard normal distribution equation to record fermentation yields of each isolate was employed to weight their different numeric scales and deviations. Following transformation, the data set was analyzed by cluster analysis. The Manhattan method for dissimilarity matrix construction along with complete linkage technique, an agglomerative method for hierarchical cluster analysis, was employed using statistical computing program R. A total of 100 isolates were classified into groups A, B, and C. In a comparison of the characteristics of each group, all characteristics in groups A and C were higher than those of group B. Isolates displaying higher cell yield were classified as group A, whereas those isolates showing high antioxidant activity and enzyme production were assigned to group C. The results of the cluster analysis can be useful for the classification of numerous isolates and the preparation of an isolation pool using numerical or statistical tools. The present study suggests that a simple technique can be applied to screen and select beneficial microbes using the freely downloadable statistical computing program R.

• 대한기계학회논문집B
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• 제26권11호
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• pp.1622-1629
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• 2002

To enhance isothermal characteristics of glass-farming surface, a rectangular parallelepiped heat pipes was fabricated, tested, and analyzed. The working fluid was sodium and the wall material was stainless steel 304. The dimension of the heat pipe was 210 (L) $\times$ 140(W) $\times$ 92(H)mm. A lattice structure covered with screen mesh was inserted to promote return of working fluid. The bottom side of heat pipe was heated electrically and the top side was cooled by liquid circulation. The temperature distribution at the bottom surface was of major concern and was monitored to determine isothermal characteristics. A frozen start-up of rectangular parallelepiped liquid metal heat pipe was tested. The operating mode of the sodium heat pipe was affected by the temperature of cooling zone, input heat flux, and the operating temperature of heat pipe. The heat pipe operated in a normal fashion as long as the heat flux was over 5.78W/cm$^2$, and the inside wall temperature of condenser part was above 95$^{\circ}C$ The maximum temperature difference at the bottom surface was observed to be 32$^{\circ}C$ when the operating temperature of the heat pipe was operating normally around 50$0^{\circ}C$. The result showed that a sodium heat pipe was very effective in reducing significantly the temperature difference in the glass-forming surface.

• 대기
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• 제23권4호
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• pp.413-424
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• 2013

Urban Heat Island (UHI) intensity is one of vital parameters in studying urban boundary layer meteorology as well as urban planning. Because the UHI intensity is defined as air temperature difference between urban and rural sites, an objective sites selection criterion is necessary for proper quantification of the spatial variations of the UHI intensity. This study quantified the UHI intensity and its spatial pattern, and then analyzed their connections with urban structure and metabolism in Seoul metropolitan area where many kinds of land use and land cover types coexist. In this study, screen-level temperature data in non-precipitation day conditions observed from 29 automatic weather stations (AWS) in Seoul were analyzed to delineate the characteristics of UHI. For quality control of the data, gap test, limit test, and step test based on guideline of World Meteorological Organization were conducted. After classifying all stations by their own local climatological properties, UHI intensity and diurnal temperature range (DTR) are calculated, and then their seasonal patterns are discussed. Maximum UHI intensity was $4.3^{\circ}C$ in autumn and minimum was $3.6^{\circ}C$ in spring. Maximum DTR appeared in autumn as $3.8^{\circ}C$, but minimum was $2.3^{\circ}C$ in summer. UHI intensity and DTR showed large variations with different local climate zones. Despite limited information on accuracy and exposure errors of the automatic weather stations, the observed data from AWS network represented theoretical UHI intensities with difference local climate zone in Seoul.