• 한국연소학회:학술대회논문집
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• 한국연소학회 1999년도 제19회 KOSCO SYMPOSIUM 논문집
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• pp.93-104
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• 1999

NOx formation in turbulent flames is strongly coupled with temperature, superequilibrium concentration of O radical, and residence time. This implies that in order to accurately predict NO level, it is necessary to develop sophisticated models able to account for the complex turbulent combustion processes including turbulence/chemistry interaction and radiative heat transfer. The present study numerically investigates the turbulent nonpremixed hydrogen jet flames using the laminar flamelet model. Flamelet library is constructed by solving the modified Peters equations and the turbulent combustion model is extended to nonadiabatic flame by introducing the enthalpy defect. The effects of turbulent fluctuation are taken into account by the presumed joint PDFs for mixture fraction, scalar dissipation rate, and enthalpy defect. The predictive capability of the present model has been validated against the detailed experimental data. Effects of nonequilibrium chemistry and radiative heat loss on the thermal NO formation are discussed in detail.

• 한국연소학회지
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• 제14권2호
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• pp.32-41
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• 2009

The transported probability density function model combined with the consistent finite volume (FV) method has been applied to simulate the turbulent bluff-body reacting flows. To realistically account for the non-isotropic turbulence effects on the turbulent bluff-body reacting flows, the present PDF transport approach is based on the joint velocity- turbulent frequency-composition PDF formulation. The evolution of the fluctuating velocity of a particle is modeled by a simplified Langevin equation and the particle turbulence frequency is represented by the modified Jayesh - Pope model. Effects of molecular diffusion are represented by the interaction by exchange with the mean (IEM) mixing model. To validate this hybrid FV/PDF transport model, the numerical results are compared with experimental data for the turbulent bluff-body reacting flows.

• 보건의료산업학회지
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• 제7권4호
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• pp.49-63
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• 2013

This study attempted to examine what effect knowledge management factors have on cooperative organizational culture regarding knowledge sharing depending on workplace types and occupations in order to seek for solution to increase efficiency and effects of knowledge management in the hospital organization. Key findings are as follows: For members of the hospital organization, the higher their recognition was in relation to 'concern and support of chief executive officer for knowledge management', and 'problem solution by specialists or superior in the organization and acquisition on the task knowledge', the more they worked as factors exerting positive effects on 'cooperative organizational culture regarding knowledge sharing'. And influence factors were different depending on workplace types and occupation.

• 대한음성학회지:말소리
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• 제61호
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• pp.31-48
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• 2007

This study investigated the roles of name agreement and word frequency in the English-Korean word translation task. Using the low-frequency homonyms with low name agreement as stimuli, Experiment 1 revealed that the name agreement of materials is a determinant which could modulate times to translate English words into Korean equivalents. On the contrary, Experiment 2 showed that the name agreement of materials does not play a decisive role in the translation task, using the low-frequency homonyms having high name agreement as stimuli. In Experiment 3, we identified that the frequency effects observed from previous two experiments are indeed brought about during the lexical access. Our findings suggest that the word frequencies of materials have a strong influence on English-Korean word translation times, and homonyms are represented independently each other in the lexeme level.

• 한국동물학회지
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• 제20권1호
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• pp.19-28
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• 1977

In order to evaluate the mutagenic potential in animal for these pesticides which were proved to be mutagenic in the bacterial screening system with a metabolic activation in vitro, we have studied in vivo cytogenetic effects on mouse bone marrow by means of the micronucleus test. The clastogenic activity of the chemical is evaluated as the frequency of micronuclei in polychromatic erythrocytes. We have tested six pesticides, insecticides, DDVP and trichlorfon, fungicide, TMTD, herbicides, NIP and MO and growth regula색, maleic hydrazide. It was found that among the tested pesticides only TMTD exhibited minimal activity in inducing micronuclei. Organophosphorus insecticide DDVP that is the most broadly used and economically important chemical, did not increase the micronuclei frequencies in mouse bone marrow cells as with the all other pesticides tested.

• 한국정밀공학회지
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• 제22권6호
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• pp.159-167
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• 2005

This work focuses on the effects of crack free friction on Mode II stress intensity factors, $K_{II}$, for a vertical surface crack in a two-dimensional finite element model of TiN/steel subject to rolling contact. Results indicate that maximum $K_{II}$ values, which occur when the load is adjacent to the crack, may be significantly reduced in the presence of crack face friction. The reduction is more significant for thick coatings than for thin. Crack extension and increased layer thickness result in increased $K_{II}$ values. The effect of crack face friction on compressive $K_I$ values appears negligible. Comparative results are presented for $MoS_2/steel$ and diamond-like carbon(DLC)/Ti systems.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2010년도 춘계학술대회 초록집
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• pp.62.1-62.1
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• 2010

CIS(CuInSe2)계 화합물 태양전지는 높은 광흡수계수와 열적 안정성 및 조성 조절을 통한 밴드갭 조절이 용이해 고효율 박막 태양전지로 각광 받고 있다. 또한 CIGS 태양전지는 기존의 유리기판 대신 유연한 기판을 사용해 flexible 태양전지 제조가 가능하다. 이러한 유연기판은 보통 stainless steel과 같은 금속 기판이 많이 사용되는데 기존의 soda-lime glass 기판과는 달리 금속기판에는 Na이 첨가되어 있지 않아 별도의 Na첨가를 필요로 한다. Na은 CIGS 흡수층의 조성조절을 용이하게 하여 태양전지의 변환 효율을 향상시키는 역할을 한다. 본 연구에서 기판은 Na이 첨가되어있지 않은 corning glass를 사용 하였으며 NaF를 이용해 Mo가 증착된 기판에 NaF의 두께를 달리하며 증착해 CIGS 흡수층의 grain 사이즈를 비교 하였으며 그 후 태양전지 소자를 제조해 광전특성을 분석하였다. 후면 전극으로 약60nm 두께의 Mo를 DC Sputtering 방법을 이용해 증착 하였다. buffer층으로는 약 50nm의 CdS층을 CBD방법을 이용하여 제조 하였으며 TCO 층으로 약 50nm의 i-ZnO와 약 450nm의 Al-ZnO를 RF Sputtering방법으로 증착 하였다. 마지막으로 앞면 전극으로 약 $1{\mu}m$의 Al을 Thermal Evaporation방법으로 증착하였다. 태양전지 소자의 면적은 $0.49cm^2$로 효율을 비교 분석하였다.

• 농업생명과학연구
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• 제45권4호
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• pp.121-133
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• 2011

Effects of roasting on vitamin E content, color, microstructure and moisture of peanuts, and vitamin E content in peanut oils prepared from the roasted peanuts were investigated. Runner-type peanuts were roasted at 140, 150, and $160^{\circ}C$ for 10-20 min. As roasting temperature and time increased, the CIELAB $L^*$ value of peanuts decreased while $a^*$ and $b^*$ values increased, resulting in formation of the golden brown color of roasted peanuts. Moisture ratio (M/Mo) and color $b^*$ value of peanuts roasted at 140 to $160^{\circ}C$ showed a correlation of $b^*=21.61\;(M/Mo)^2-40.62\;(M/Mo)+34.12$ ($R^2=0.9123$). Overall changes in the tocopherol contents of peanuts and peanut oils were significantly affected by roasting temperature and time (p<0.05). Roasting at $140^{\circ}C$ caused a slight increase in the levels of tocopherols of peanuts over roasting time up to 20 min (p<0.05). There was no significant change in the tocopherol levels of peanuts during roasting at $150^{\circ}C$ for 20 min (p>0.05). At $160^{\circ}C$, the levels of tocopherols significantly decreased during the initial 10 min of roasting (p<0.05) while there was no extended loss after 10 min, resulting in about 5, 12, 20, and 10% losses of ${\alpha}$-, ${\beta}$-, ${\gamma}$- and ${\delta}$-T, respectively. After 20 min, total tocopherols decreased by 18%. However, tocopherol contents of pressed peanut oils significantly decreased at all roasting temperatures (p<0.05). After roasting peanuts at $160^{\circ}C$ for 20 min, about 84% of initial ${\alpha}$-T in peanut oils was retained. ${\alpha}$-T was the most stable to roasting while ${\gamma}$-T was the least. Swollen epidermal cells on the inner surface and broken cell walls of parenchyma tissue of peanut cotyledon were observed in peanuts after roasting at $160^{\circ}C$ for 15 min. Severe changes in microstructure of peanut by roasting would contribute to vitamin E stability because of exposure of oil droplets in peanuts to oxygen.

• 한국콘텐츠학회논문지
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• 제18권2호
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• pp.642-651
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• 2018

본 연구의 목적은 부모의 양육태도가 청소년의 공격성에 미치는 영향과 또래애착 매개효과를 검증하는 것이며, 이를 위해 한국아동 청소년패널조사 초4 7차 년도 데이터를 사용하였다. 연구결과는 다음과 같다. 첫째, 다중공선성 VIF 값을 사용하여 양육태도, 공격성, 또래애착 변인 간의 상관관계를 확인 하였다. 둘째, 부모의 양육태도가 청소년의 공격성에 유의하게 영향을 미치는 것으로 나타났다. 셋째, 부모의 양육태도가 청소년의 공격성에 미치는 영향에서 또래애착이 부분매개효과가 있은 것으로 나타났다. 또한 매개효과 유의성 검증을 위해 Sobel Test를 실시하였다. 본 연구의 결과는 경험적 근거로 의미를 가지며, 이를 토대로 부모를 대상으로는 부모교육프로그램과 청소년을 대상으로는 또래애착 강화 프로그램이 사회복지개입실천에서의 필요성을 제언하였다.

• 한국전자통신학회논문지
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• 제12권1호
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• pp.219-228
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• 2017

본 연구는 테블릿 pc 어플리케이션을 사용한 인지훈련이 인지 손상이 있는 아급성 뇌졸중 환자의 인지기능, 일상생활 및 만족감에 미치는 영향을 알고자 하였다. 인천에 소재한 I병원에 입원 중인 14명의 아급성 뇌졸중 환자들이 본 연구에 참여하였다. 14명의 대상자들은 실험군과 대조군으로 7명씩 무작위 배정되었다. 두 그룹의 대상자들은 모두 전통적인 인지치료를 4주간 주 5회, 1일 30분의 중재를 받았으며, 실험군은 테블릿 pc 어플리케이션을 사용한 인지훈련을 30분씩 추가적으로 실시하였다. 평가는 중재 전과 후에 한국판 간이 정신상태 검사, 한국판 몬트리올 인지평가, 수정된 바델 지수, 시각 상사 척도를 사용하여 인지기능, 일상생활, 만족감을 측정하였다. 연구 결과, 두 그룹은 중재 전과 후로 몬트리올 인지평가와 수정된 바델 지수에서 유의한 향상을 보였다(p<.05). 두 그룹 간 변화량 비교에서 실험군은 대조군보다 몬트리올 인지평가에서 유의한 향상을 보였다(p<.05). 두 그룹 간 만족감 비교에서 실험군과 대조군은 유의한 차이가 없었다(p>.05). 본 연구의 결과를 통하여 테블릿 pc 어플리케이션을 사용한 인지훈련은 아급성 뇌졸중 환자의 인지기능 향상에 긍정적인 효과를 기대할 수 있는 중재법으로 사료된다.