• Journal of Magnetics
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• 제11권2호
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• pp.90-94
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• 2006

A finite-element method is used to analyze loss generation and electromagnetic noise absorption characteristics of a coplanar waveguide transmission line integrated with a magnetic thin film. Parameters used in the analysis are the electrical resistivity of the magnetic layer and the thickness of both magnetic and insulating layers. The results indicate that L-C resonance is the main loss mechanism of the electromagnetic noise absorption.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book I
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• pp.491-497
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• 2003

The use of both an Alpha Hydroxy Acid, Citric Acid, and a Skin Moisturizer, Glycereth-26, formulated into a hand dishwashing detergent have been shown to be synergistic in their effects on certain skin health parameters. Each ingredient was evaluated alone and together in a hand dishwashing detergent via a 9-week use test. Panelists washed dishes using the sponge method commonly used in Asian markets and a 1:7 dilution of the concentrated dish detergent. Panelist's hands were evaluated initially and at 3-week intervals for nine weeks. After nine weeks panelist's hands showed significant improvements in Moisture Absorption and Transepidermal Water Loss (TEWL). A synergistic effect on TEWL was found between the AHA and the Moisturizer. These effects, showing an improvement in the condition of the panelist's skin are impressive, particularly since they were observed from a dishwashing product that is highly diluted and at near neutral pH during the washing process.

• 대한화장품학회:학술대회논문집
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• 대한화장품학회 2003년도 IFSCC Conference Proceeding Book II
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• pp.417-423
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• 2003

The use of both an Alpha Hydroxy Acid, Citric Acid, and a Skin Moisturizer, Glycereth-26, formulated into a hand dishwashing detergent have been shown to be synergistic in their effects on certain skin health parameters. Each ingredient was evaluated alone and together in a hand dishwashing detergent via a 9-week use test. Panelists washed dishes using the sponge method commonly used in Asian markets and a 1:7 dilution of the concentrated dish detergent. Panelist's hands were evaluated initially and at 3-week intervals for nine weeks. After nine weeks panelist's hands showed significant improvements in Moisture Absorption and Transepidermal Water Loss (TEWL). A synergistic effect on TEWL was found between the AHA and the Moisturizer. These effects, showing an improvement in the condition of the panelist's skin are impressive, particularly since they were observed from a dishwashing product that is highly diluted and at near neutral pH during the washing process.

• ETRI Journal
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• 제42권4호
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• pp.575-584
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• 2020

Electromagnetic (EM) waves used to send signals under seawater are normally restricted to low frequencies (f) because of sudden exponential increases of attenuation (𝛼) at higher f. The mathematics of EM wave propagation in seawater demonstrate dependence on relative permeability (𝜇_r), relative permittivity (𝜀_r), conductivity (𝜎), and f of transmission. Estimation of 𝜀_r and 𝜎 based on the W. Ellison interpolation model was performed for averaged real-time data of temperature (T) and salinity (S) from 1955 to 2012 for all oceans with 41 088 latitude/longitude points and 101 depth points up to 5500 m. Estimation of parameters such as real and imaginary parts of 𝜀_r, 𝜀_r', 𝜀_r", 𝜎, loss tangent (tan 𝛿), propagation velocity (V_p), phase constant (𝛽), and α contributes to absorption loss (L_a) for seawater channels carried out by using normal distribution fit in the 3 GHz-40 GHz f range. We also estimated total path loss (L_PL) in seawater for given transmission power P_t and antenna (dipole) gain. MATLAB is the simulation tool used for analysis.

• 한국해양공학회지
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• 제2권2호
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• pp.130-137
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• 1988

This thesis introduced that character of a treatment technique for a mading synthetic resin Hifiow-Ring. The material system of packings make an experiment air$NH_{3}$/air$H_{2}SO_{4}$, $SO_{2}$-air/NaOH, $NH_{3}$-air/$/H_{2}SO_{4}$ under general conditions. Lattices packing compared with conventional packings was proved low pressure loss and high separation efficiency for high loading per trans unit. And an inflow materal tested for absorption and rectification, it made an experiment under a range regular temperature, low energy and small amount of money. That made possible in simple equation, volume material tranfer coefficient$\beta_{L}$ . a by absorption or $\beta_{V}$ .a calculated in all range loading. The peculiarity pressure loss $\Delta\;P/NUT_{ov}$ for Hiflow-ring contributed to a fall cost of energy, a grade number of a vacuum rectification and absorption calculation.

• 한국재료학회지
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• 제14권2호
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• pp.152-156
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• 2004

We have studied the effective optical absorption power of Si solar cell with $SiO_2$-antireflection layer based on a mathematical modelling of AM(air mass)1 spectrum and Si refractive index in the wavelength range(0.4 $\mu\textrm{m}\leq$λ$\leq$$0.97\mu\textrm{m}$). The effective optical absorption power obtained from the theoretical calculation was 450 and 520 W/$\m^2$ for the Si solar cells with $SiO_2$-antireflection layer of 500$\AA$ and 1000$\AA$, respectively. The optimum thickness of $SiO_2$-antireflection layer showing the minimum reflection loss was about 1000$\AA$ in the computer simulation. Two kinds of Si solar cells named EBS(500$\AA$) and EBS(l000$\AA$) were fabricated to evaluate the effect of $SiO_2$-antireflection layer thickness on the optical absorption. The epitaxial base Si cell with $SiO_2$-antireflection layer of 1000$\AA$ [EBS(l000$\AA$)] showed the output power improvement of about 15% upon the EBS(500$\AA$) cell due to larger absorption of effective optical power under illumination of AM1, 1 sun.

• 한국자기학회지
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• 제27권2호
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• pp.49-53
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• 2017

THz 대역 전파흡수체를 구현하기 위해 split cut wire(SCW)와 배면 도체로 구성되는 단위 셀 구조를 제안하였다. 배면이 금속으로 단락된 유전체 기판 상에 SCW가 배열된 메타소재에서 SCW의 길이와 폭을 조절하여 THz 대역에서 완전 전파흡수체(5.5~6.0 THz에서 반사손실 -20 dB 이하)의 구현이 가능하였고, 인덕턴스-커패시턴스 (L-C) 공진기 회로이론으로 이를 설명하였다. 길이가 서로 다른 두 개의 SCW를 하나의 단위 셀 안에 같이 배치함으로써 두 개의 흡수 피크를 얻을 수 있었다. SCW 간의 간격이 넓어짐에 따라 두 번째 공진주파수는 거의 변화가 없지만 첫 번째 공진주파수는 저주파로 이동하면서 반사손실 값이 현저히 감소하는 경향이 나타났다.

• 한국조명전기설비학회지:조명전기설비
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• 제7권6호
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• pp.42-50
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• 1993

본 논문에서는 플랜트 모델에 불확실성이 존재하는 경우에도 강인 안정도를 보장하는 제어기 설계 문제를 연구하였다. 먼저 강인 안정도 및 감도 특성을 특이치 한계를 이용하여 기술하고 이들 설계 조건을 만족하는 제어기 설계 기법을 Diophantine 방정식과 감도 평가 함수의 최소화에 의해 제시하였다. Diophantine 방정식의 해를 구하기 위해 칼만 필터의 설계와 필터의 주파수 역 특성을 조사하였고, 원하는 특이치 형성을 통해 저감도 특성을 만족하는 특성 다항식 행렬을 구하였다. 그리고 제어기에 설계 자유도를 주어 감도 평가 함수를 최소화하는 제어기 매개 변수 계산 방법을 Routh 배열을 이용하여 제시하였다.제안된 강인한 제어기 설계 기법을 모델에 적용하여 검토해 본 결과 만족스러운 결과를 얻을 수 있었다.

• 한국조명전기설비학회지:조명전기설비
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• 제7권2호
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• pp.51-56
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• 1993

Epoxy 복합재료의 충전제 및 수분함유의 유전특성에 대한 영향을 고찰한 결과를 요약하면 다음과 같다. 1) ${\varepsilon}_\tau$의 주파수 의존성은 시편1과 시편2의 경우에서 $140^{\circ}C$이하에서 직선적인 특성을 나타내고 있으며 수분의 함유시에도 직선적인 변화를 하고 있으므로 주파수나 습도 센서소자로서 개발이 가능하다. 2) 100[Hz]~3[kHz]의 범위에서 $tan{\delta}$ 주파수 의존성은 캐리어 이동에 의한 도전손실 보다 쌍극자완화에 의한 손실이 지배적이며 수분에 영향은 낮은 주파수에서 크게 받는다.

• Bulletin of the Korean Chemical Society
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• 제20권6호
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• pp.677-682
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• 1999

Conjugated polycarbosilanes with diacetylene and aromatic groups of thiophene or phenylene simultaneously present in the polymer backbone such as poly[[1,4-bis(thiophenyl)buta-1,3-diyne]-alt-(dimethylsilane)], poly[[1,4-bis(thiophenyl)buta-1,3-diyne]-alt-(diphenylsilane)], poly[[1,4-bis(phenyl)buta-1,3-diyne]-alt-(dimethylsilane)],and poly[[1,4-bis(phenyl)buta-1,3-diyne]-alt-(diphenylsilane)] have been prepared. The characteristic C=C stretching frequencies appear at 2177-2179㎝-1 in the IR spectra of the polymers. The molecular weights of these polymers were detemined by GPC. All of these materials are soluble in organic solvents such as THF and chloroform, and thermally stable up to 200℃ in general without any weight loss under nitrogen. The prepared materials in THF solvent show a maximum absorption peak in the range of 334-356 nm with a molar absorptivity of 10³∼10ⁿ(n=5)L/(cm·mol) in the UV-visible absorption spectra. A maximum emission peak in the range of 403-550 nm is also observed in the fluorescence emission spectra. Both absorption and emission spectra strongly indicate that the obtained polycarbosilanes contain the new conjugated systems along the polymer main chain.