• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1997년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Fall 1997
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• pp.152-159
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• 1997

An analytical method is developed to study the propagation of surface waves across infilled trenches. The Green's function technique is used to estimate the reflection and transmission coefficients of Rayleigh waves across a semi-infinite plate inserted between two homogeneous quarter-spaces. After validating the method against experimental data, influence of the material contrast and the angle of incidence on the screening effectiveness of an infilled trench is examined.

• 한국지진공학회:학술대회논문집
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• 한국지진공학회 1998년도 춘계 학술발표회 논문집 Proceedings of EESK Conference-Spring 1998
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• pp.106-112
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• 1998

A numerical experiment is conduced to study the wave screening effectiveness of wave barriers which are constructed to reduce the ground-transmitted vibration. The finite element method is used for the simulation of the wave propagation behavior. In order to reduce the computational burden the absorbing boundary's one employed. Validity of the numerical model is checked by comparing the results with the published data. The screening effectiveness of the in filled trenches is then studied for different trench dimensions and material properties.

• 공업화학
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• 제10권8호
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• pp.1155-1160
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• 1999

본 스크리닝 방법론에서는 저장탱크 및 압력방출장치로부터 누출되는 기상흐름의 누출에 대한 대기분산 모델링 절차가 고려되었다. 본 연구는 화학장치 설비 중 염소 저장탱크의 누출유형에 따른 누출물의 물성자료들을 포함하는 누출원모델, 분산모델, 기상 및 지형자료들을 TSCREEN 모델에 입력시켜 염소가스의 풍하거리에 따른 1시간 평균 최대 지표면 농도를 산출함으로써 유해독성가스의 누출 예측 및 제어를 위한 스크리닝 방법론을 개발하기 위한 것이다. 연구결과로부터, 공기보다 무거운 가스의 분산유형은 누출물의 상태, 누출 조건, 누출물의 물리 화학적특성, 누출유형(연속 및 순간누출)에 영향을 받고 있으며, 특히 누출물의 초기(감압) 밀도 및 누출속도 뿐만 아니라 풍속에 커다란 영향을 받고 있음을 알 수 있다. 특히, 기상조건(대기안정도 및 풍속)에 따른 유해물질의 대기중 누출을 살펴보았다. 본 스크리닝 방법론은 보다 다종다양한 시나리오들을 선정하여 보편적으로 적용할 수 있는 Sliding Scale 방법론을 개발함으로써 정교한 해석 모델의 적용시 예비 가이드라인으로 활용될 수 있으리라 사료된다.

• 한국전기전자재료학회논문지
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• 제11권3호
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• pp.181-187
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• 1998

The ionization energy and degree of ionization for p-type $Si_{1-x}Ge_x$ with boron doping are calculated taking into account the screening and broadening effects. The drift and Hall mobilities are then calculated using the relaxation time approximation and compared with the previously reported measurement data for relaxed and strained $Si_{1-x}Ge_x$ alloys to estimate the alloy scattering potential. From a fit, the alloy scattering potential is found to be 0.5 eV. The in-plane drift mobility for p-type strained $Si_{1-x}Ge_x$ grown on (001) Si substrate is approximately 1+$10x^2$ times higher than that for bulk Si in the high doping range.

• Bulletin of the Korean Chemical Society
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• 제30권5호
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• pp.1177-1180
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• 2009

• 식품과학과 산업
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• 제45권3호
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• pp.15-22
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• 2012

• 대한화장품학회지
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• 제36권1호
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• pp.47-55
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• 2010

기존의 유기계 자외선차단제는 피부에 대한 자극과 투과의 문제, 무기계 자외선차단제는 백탁현상 등 몇 가지 문제점이 알려져 있다. 최근에 보다 효과적인 자외선차단제를 개발하기 위한 연구가 진행되고 있으며, 그 중의 하나가 유기/무기 복합구조의 자외선차단제에 대한 연구이다. 본 연구진은 새로운 자외선차단제인 메톡시선나마도프로필폴리설세스퀴옥산의 제조와 그 효과에 대해 보고한 바 있다. 특별히, 본 연구는 신규 자외선차단제의 화학적 구조에 대한 정성적인 분석과 향상된 자외선차단 효과 및 화장료 제형에 대한 적용성을 평가하였다. 자외선차단제의 구조분석은 TGA, solid state NMR, 원소분석을 이용하여 평가하였으며, 자외선차단지수는 5 wt%를 포함하는 제형을 평가하였을 때, 6.0 정도의 수치를 보였다. 또한 기존의 유기 및 무기 자외선차단제와 혼합적용 시, 자외선차단효과에 대한 우수한 시너지 효과를 나타내었으며 W/S 유형의 화장료 제형에서 우수한 적용성을 보였다.

• 한국미생물·생명공학회지
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• 제21권3호
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• pp.288-292
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• 1993

An agar medium(HY) was developed to detect the urease-producing lactic acid bacteria. HY medium was prepared with the addition of tryptone, glucose and tween 80 to the supernatant of autoclaved skim milk and yeast extract mixture. There was no difference in eumeration of lactic acid bacteria between the HY and commercial media, such as M17, MRS and BCP agar. The urease activity of Streptococcus salivarius subsp. thermophilus was detected on the HY agar medium contained urea by the color change of bromocresol purple as the pH indicator, but not on the commerical agar media. Furthermore, it was succeeded to screen the urease activity of bacteria in skim milk used as a raw material in dairy product manufacture. Therefore, HY medium was proved to be suitable for the screening of urease-producing lactic acid bacteria.

• Molecular & Cellular Toxicology
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• 제4권2호
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• pp.100-105
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• 2008

Biochips are a powerful emerging technology for biomedical, environmental applications. Especially, making use of bioseonors in the evaluation of toxicity becomes increasingly important. For biosensor as a toxicity detection, biomolecules like antibodies or aptamers have been developed to specifically capture the toxic target molecules. In addition, the development of optimal chip materials capable of maintaining the activity of embedded biomolecules such as proteins or aptamers has proven challenging. Here, using sol-gel materials, new chip material, whose ability for immobilizing the embedded aptamers and maintaining the ability of embedded aptamers is optimal, was searched. We used sol-gel formulation screening methods previously developed and found the best formulation which shows high sensitive and specific interactions of aptamers. This study results will support the technological advancement for diagnosis and environmental sensor.

• Geomechanics and Engineering
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• 제13권2호
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• pp.269-284
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• 2017

A new technique is proposed to obtain more effective screening efficiency against the ground vibration using intermittent geofoam (IF) in-filled trench. The numerical analysis is performed by employing two-dimensional finite element method under dynamic condition. Vertically oscillated strip foundation is considered as the vibration source. In presence of the ground vibration, the vertical displacements at different locations (pick-up points) along the ground surface are captured to determine the amplitude reduction factor (ARF), which helps to assess the efficiency of the vibration screening technique. The efficiency of IF over continuous geofoam (CF) in-filled vibration barriers is assessed by varying the geofoam density, the location of trench and the frequency of excitation. The results from this study indicate that a significant reduction in ARF can be achieved by using intermittent geofoam as compared to continuous geofoam. Further, it is noticed that the efficiency of IF increases with an increase in the frequency of the vibrating source. These encouraging results put forward the potential of utilising intermittent geofoam as a vibration screening material.