• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.71-72
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• 2009

칼코게나이드(chalcogenide)계 비정질 반도체는 그들의 독특한 광학적, 전기적 특성 때문에 활발한 연구가 진행되고 있다. 비정질 Se는 유연한 원자구조로 인해 가장 먼저 광학적으로 상용화되었으며, 응용성이 매우 큰 반도체 재료중 하나로 Ge-Se와 같이 Se를 기본으로 한 칼코게나이드 유리 반도체가 주목받고 있다. 따라서 본 연구에서는 비정질 칼코게나이드 $Ge_xSe_{100-x}$(x=25,95) 조성에 대한 광학적 특성을 연구 하였다. 시료는 5N의 순도를 갖는 Ge, Se 물질을 준비하고 조성비에 맞추어서 석영관에 진공 봉입한 후 용융 혼합하여 $Ge_{25}Se_{75}$와 $Ge_{95}Se_5$조성의 두 가지 비정질 벌크를 제작하였다. 열증착 방법으로 유리 기판위에 박막을 제작하였고 UV-vis-NIR spectrophotometer를 사용하여 투과도를 측정하였다. 측정한 스펙트럼을 이용하여 Swanpoel method로 굴절률을 계산하고 특성을 분석하였다.

• Journal of the Korean Society of Systems Engineering
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• v.8 no.2
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• pp.1-10
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• 2012

This paper aims to analyze the result of SE Process Implementation on Light Rail Transit(LRT) Project. Currently the Light Rail Transit Project of Korea applies SE to the intermediate phase, that is, E&M phase which is a manufacturing and designing procedure. More seriously, the application effect of SE is not remarkable because it applies to some specific engineering fields like RAMS and it depends on superficial consulting of foreign companies with low SE support capability and investment capital. This study points out that the "Requirement Analysis" and "System Alternative Review" has not been conducted from the initial phase (basic plan and basic design) of the LRT projects. Several projects indicate that the amount of investments for SE activities through the Korea LRT project is relatively very small in comparison with the global capital which is about 10% of total project budget. Furthermore, Korea LRT projects have very few SE professionals and weak SE organization with no government directions and guide book for the efficient implementation of SE for the LRT projects.

• Proceedings of the KIEE Conference
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• 1999.11a
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• pp.10-12
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• 1999

Optical properties of $Zn_2AgGaSe_4$ and $Zn_2AgGaSe_4$:$Co^{2+}$ crystals are investigated in the visible and near-infrared regions at 298K. The direct band gap at 298K is 1.630eV for the $Zn_2AgGaSe_4$ and 1.567eV for the $Zn_2AgGaSe_4$:$Co^{2+}$ crystals, respectively. In the optical absorption and PAS spectrum of the $Zn_2AgGaSe_4$:$Co^{2+}$, we observed five impurity absorption peaks at $4220cm^{-1}$, $5952cm^{-1}$, $12422cm^{-1}$, $12987cm^{-1}$ and $14184cm^{-1}$. These impurity absorption peaks are attributed to the electronic transitions between the split energy levels of $Co^{2+}$ ions with Td symmetry of $Zn_2AgGaSe_4$ host lattice. The crystal field parameter Dq, the Racah parameter B and the spin-orbit coupling parameter $\lambda$ are given by $442cm^{-1}$, $425cm^{-1}$ and $440cm^{-1}$, respectively.

• Journal of the Korean Vacuum Society
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• v.21 no.6
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• pp.322-327
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• 2012

The strain effects of ZnSe epilayer on ZnSe/GaAs heterojunction structure grown by molecular beam epitaxy have been investigated by using electroreflectance (ER) spectroscopy. The ER measurements were performed as a function of modulation voltage, dc bias voltage, and temperature. From the room temperature ER spectrum, we observed a heavy-hole (HH: 2.609 eV) and light-hole (LH: 2.628 eV) transitions due to a compressive strain. With increasing the bias voltage, the amplitude of HH transition signal decreased and the amplitude of LH transition signal was almost the same. From the temperature dependence of ER spectra, we have studied the interaction between the strain and the thermal expansion coefficient.

• Solar Energy
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• v.10 no.2
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• pp.59-68
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• 1990

In this paper, photoconductive pure CdSe films and CdSe films doped with various impurities are fabricated by vaccum deposition and subsequent heat treatment in vaccum. The substrate is kept at $200^{\circ}C$ during deposition and temperature generally makes the films more photoconductive. The photocurrent of the films increase linearly with light illumination. Spectral response of photoconductivity is measured at the wave length range of 380nm to 850nm. The maximum response is found at 700nm in pure CdSe films, but it shifts to the longer wavelength in impurity-doped CdSe films. Photo-response of the pure CdSe films are more sensitive at lower temperature, while the impurity-doped films show the opposite trend.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.52 no.1
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• pp.1-5
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• 2003

Zn$_4$SnSe$_{6}$ and Zn$_4$SnSe$_{6}$ :Co$^{2+}$ single crystals were by the chemical transport reaction method. They crystallized in the monoclinic structure. The direct energy band gaps of the Zn$_4$SnSe$_{6}$ and Zn$_4$SnSe$_{6}$ :Co$^{2+}$single crystals at 289k were found to be 2.146eV and 2.042eV. Optical absorption due to impurity in the Zn$_4$SnSe$_{6}$ :Co$^{2+}$single crystal was observed and described as originating from the electron transition between energy levels of Co$^{2+}$ion sited at T$_{d}$ symmetry point.y point.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.52 no.2
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• pp.68-73
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• 2003

$Zn_4SnSe_6$ and $Zn_4SnSe_6:Co^{2+}$ single crystals were grown by the chemical transport reaction(CTR) method. They were crystallized in the monoclinic structure. These temperature dependence of the optical energy gap were closely investigated over the temperature range 10[K]~300[K]. The direct energy gaps of $Zn_4SnSe_6$ and $Zn_4SnSe_6$:$Co^{2+}$ single crystals were given by 2.146[eV] and 2.042[eV] at 300[K]. The temperature dependence of the optical energy gap is well presented by the Varshni equation.

• Korean Journal of Poultry Science
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• v.40 no.1
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• pp.75-81
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• 2013

This experiment was conducted to investigate the effects of bacteriophage SE supplementation on growth performance, nutrient digestibility, blood profiles, visceral organ weight, meat quality and excreta microflora in broilers. A total of 340 1-d-old ROSS 308 broilers (mixed gender) with an initial average body weight (BW) of $41.71{\pm}0.16$ g were randomly allotted to 4 treatments with 5 replicate pens per treatment and 17 broilers per pen for 31 days. Dietary treatments were: 1) CON, control diet, 2) SE05, CON+0.05% bacteriophage, SE 3) SE10, CON+0.10% bacteriophage SE, and 4) SE15, CON+0.15% bacteriophage SE. During d 15 to 31, broilers fed SE15 diet had a higher (P<0.05) body weight gain than broilers fed CON diet. Overall, body weight gain in SE10 and SE15 was greater (P<0.05) than that in CON. Apparent total tract nutrient digestibility and blood characteristics did not differ (P>0.05) among treatments. The water holding capacity was increased (P<0.05) in SE15 compared with CON. Other meat quality in terms of pH value, breast muscle color ($L^*$, $a^*$, $b^*$) and drip loss were unaffected by dietary supplementation with bacteriophage SE. The visceral weight of bursa of Fabricius was increased (P<0.05) in broilers fed the bacteriophage SE incorporated diets compared with those fed the CON diet. No difference (P>0.05) was observed in visceral weight of liver, spleen, breast muscle, abdominal fat, gizzard and excreta concentrations of Lactobacillus, Clostridium perfringens, Escherichia coli, and Salmonella. In conclusion, dietary supplementation with 0.10 and 0.15% bacteriophage SE could improve the growth performance, breast muscle water holding capacity and bursa of Fabricius visceral weight in broilers.

• Journal of the Korean Institute of Telematics and Electronics
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• v.15 no.1
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• pp.5-11
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• 1978

Si-ZnSe n-n heterojunction was made by growing ZnSe thin film on the Si single crystal (111) surface with Bash evaporating method in vacuum. This heterojunction was found to be a useful device for frequency meter in the visible wave-length from the measuring of the photovoltaic effect of the heterojunction.

• Proceedings of the Korean Information Science Society Conference
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• 2006.06a
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• pp.139-141
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• 2006

내장형 프로세서인 SE3208의 소프트웨어 모델을 개발하고 SimpleScalar 도구 모음에 추가하여 SE3208 프로세서를 위한 시뮬레이터를 개발하였다. 소프트웨어 모델은 Simplescalar 도구의 환경에 맞춰 함수를 재사용하는 방법으로 작성되었으며, 3단 단일 파이프라인을 갖는 SE3208을 cycle단위로 시뮬레이션 할 수 있도록 시뮬레이터를 변경하였다. 동일한 프로그램을 SE3208 소프트웨어 모델과 PC 상에서 각각 실행시켜 그 결과를 비교함으로써 개발된 시뮬레이터의 정확성을 검증하였으며. 다양한 방식과 모드의 시뮬레이션 기능을 검증하고 성능을 비교하였다.