• 대한전자공학회논문지SD
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• 제37권2호
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• pp.5-12
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• 2000

열전퇴의 고온 접합부가 Si/sub 3/N/sub 4//SiO/sub 2//Si/sub 3/N/sub 4/ 멤브레인에 의해 실리콘 기판으로부터 열차단되고, 열전퇴의 저온 접합부는 방열판 역할을 하는 실리콘 림(rim)에 의해 지지되는 멤브레인위에 놓여지며, Au-black이 적외선 흡수체로 사용되는 비냉각 금속 박막형 열전퇴 적외선 검지기를 제작하고, 적외선 검지기의 성능지수에 대해 논의하였다. 3∼14㎛의 파장범위에서 Au-black의 적외선 흡수도는 대개 90%정도였고, Au 증발시의 챔버압력 및 증착된 Au-black의 단위면적당 질량에 크게 의존하였다. 쵸핑 주파수가 5 Hz일 때 Bi-Sb 열전퇴 적외선 검지기의 전압 감응도, 잡음등가전력 및 비검지도는 실온의 공기중에서 각각 약 10.5V/W, 2.3 ㎻/㎐½, 및 1.9×10/sup 7/㎝·㎐½/w였다.

• 한국재료학회:학술대회논문집
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• 한국재료학회 2010년도 춘계학술발표대회
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• pp.12.1-12.1
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• 2010

We have developed a facile method to position different dyes (N719 and N749) sequentially in a mesoporous TiO2 layer through selective desorption and adsorption processes. Only upper part of the first adsorbed N719 dye was selectively removed by the desorption solution formulated with polypropylene glycol and tetrabutylammonium hydroxide without any damages of the dye. The desorption depth was controlled by the number of desorption process. Multi-dyed dye-sensitized solar cells (MDSSC) were fabricated by utilizing the method and their photovoltaic properties were investigated. From the incident photon-to-current conversion efficiency (IPCE) measurement, it was found that the MDSSC exhibited the extended spectral response for the solar spectrum while without decrease of maximum IPCE value compare to the DSSCs using one kind of dye (N719 or N749). The highest photocurrent density of 19.3 mA/cm2 was obtained from the MDSSC utilizing $15\;{\mu}m$ N719 / $14\;{\mu}m$ N749 bi-layered mesoporous TiO2 film. The photocurrent density was 25% and 8% higher than that of the DSSC using only N719 and N749 dye as a sensitizer, respectively. The power conversion efficiency of 9.8% was achieved from the MDSSC under the AM 1.5G one sun illumination.

• Archives of Metallurgy and Materials
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• 제64권2호
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• pp.591-595
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• 2019

In this study, an oxide reduction process and a reduction-sintering process were employed to synthesize a thermoelectric alloy from three thermoelectric composite oxide powders, and the thermoelectric properties were investigated as a function of the milling duration. Fine grain sizes were analyzed by via X-ray diffraction and scanning electron microscopy, to investigate the influence of the milling duration on the synthesized samples. It was found that microstructural changes, the Seebeck coefficient, and the electrical resistivity of the compounds were highly dependent on the sample milling duration. Additionally, the carrier concentration considerably increased in the samples milled for 6 h; this was attributed to the formation of antisite defects introduced by the accumulated thermal energy. Moreover, the highest value of ZT (=1.05) was achieved at 373K by the 6-h milled samples. The temperature at which the ZT value maximized varied according to the milling duration, which implies that the milling duration of the three thermoelectric composite oxide powders should be carefully optimized for their effective application.

• Parasites, Hosts and Diseases
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• 제48권4호
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• pp.297-301
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• 2010

Recently, emerging waterbome protozoa, such as microsporidia, Cyclospora, and Cryptosporidium, have become a challenge to human health worldwide. Rapid, simple, and economical detection methods for these major waterborne protozoa in environmental and clinical samples are necessary to control infection and improve public health. In the present study, we developed a multiplex PCR test that is able to detect all these 3 major waterborne protozoa at the same time. Detection limits of the multiplex PCR method ranged from $10^1$ to $10^2$ oocysts or spores. The primers for microsporidia or Cryptosporidium used in this study can detect both Enterocytozoon bieneusi and Encephalitozoon intestinalis, or both Cryptosporidium hominis and Cryptosporidium paNum, respectively. Restriction enzyme digestion of PCR products with BsaBI or BsiEI makes it possible to distinguish the 2 species of microsporidia or Cryptosporidium, respectively. This simple, rapid, and cost-effective multiplex PCR method will be useful for detecting outbreaks or sporadic cases of waterborne protozoa infections.

• 천문학회보
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• 제46권2호
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• pp.71.1-71.1
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• 2021

We perform disk-halo decomposition of the Large Magellanic Cloud (LMC) using a novel HI velocity field extraction method, aimed at better deriving its HI kinematics and thus mass distribution in the galaxy including both baryons and dark matter. We decompose all the line-of-sight velocity profiles of the combined HI data cube of the LMC, taken from the Australia Telescope Compact Array (ATCA) and Parkes radio telescopes with an optimal number of Gaussian components. For this, we use a novel tool, the so-called BAYGAUD which performs profile decomposition based on Bayesian MCMC techniques. From this, we disentangle turbulent non-ordered HI gas motions from the decomposed gas components, and produce an HI bulk velocity field which better follows the global circular rotation of the galaxy. From a 2D tilted-ring analysis of the HI bulk velocity field, we derive the rotation curve of the LMC after correcting for its transverse, nutation and precession motions. The dynamical contributions of baryons like stars and gaseous components which are derived using the Spitzer 3.6 micron image and the HI data are then subtracted from the total kinematics of the LMC. Here, we present the bulk HI rotation curve, the mass models of stars and gaseous components, and the resulting dark matter density profile of the LMC.

• 천문학회보
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• 제45권1호
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• pp.60.3-61
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• 2020

We perform disk-halo decomposition of the Large Magellanic Cloud (LMC) using a novel HI velocity field extraction method, aimed at better deriving its HI kinematics and thus the dark matter density profile. For this, we use two newly developed galaxy kinematic analysis tools, BAYGAUD and 2DBAT which have been used for the kinematic analysis of resolved galaxies from Australian Square Kilometre Array (ASKAP) observations like WALLABY which is an all-sky HI galaxy survey in southern sky. By applying BAYGAUD to the combined HI data cube of the LMC taken with the Australia Telescope Compact Array (ATCA) and Parkes radio telescopes, we decompose all the line-of-sight velocity profiles into an optimal number of Gaussian components based on Bayesian MCMC techniques. From this, we disentangle turbulent non-circular gas motions from the overall rotation of the galaxy. We then derive the rotation curve of the LMC by applying 2DBAT to the separated circular motions. The rotation curve reflecting the total kinematics of the LMC, dark and baryonic matters is then be combined with the mass models of baryons, mainly stellar and gaseous components in order to examine the dark matter distribution. Here, we present the analysis of the extracted HI gas maps, rotation curve, and J, H and K-band surface photometry of the LMC.

• 한국안광학회지
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• 제16권3호
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• pp.339-343
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• 2011

목적: 본 연구에서는 안경렌즈의 색상과 농도에 따른 사위도의 변화를 알아보았다. 방법: 20~40세까지의 남녀 대학생 39명을 대상으로 무착색, 적색, 회색, 갈색, 녹색렌즈 를 각각 20%, 50%, 80%로 농도를 달리하여 착용 후 원거리 사위도를 측정하였다. 사위측정은 완전교정상태에서 포롭터(VT-SE, Topcon, Japan)를 이용하여 프리즘 분리법(Vongraefe technique)으로 측정하였다. 결과: 전체 대상자를 정위군, 내사위군, 외사위군으로 나누어서 실험하였다. 정위군에서는 모든 색상과 농도에서 약간의 내사위가 발생하였다. 내사위군에서는 평균 2.07${\Delta}$,BO 이던 사위도가 모든 색상과 농도에서 증가함을 보였고 특히, 갈색렌즈에서 가장 큰 증가를 보였다. 외사위군에서는 평균 3.82${\Delta}$,BI이던 사위도가 모든 색상과 농도에서 다소 감소함을 보였고 특히, 녹색렌즈에서 평균 2.95${\Delta}$,BI로 가장 큰 감소를 보였다. 같은 색상에서 농도를 달리하여 측정한 값은 통계적 유의성이 없었다. 결론: 안경렌즈의 색상에 따라 사위도의 변화가 확인되므로 렌즈의 색상을 선택함에 있어 사위도를 고려해야하며 안위이상의 피로도를 줄일 수 있는 색상을 찾는 기준이 마련되어야 할 것이라 사료된다.

• 전자통신동향분석
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• 제38권1호
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• pp.17-25
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• 2023

Topological insulators (TIs) emerge as one of the most fascinating and amazing material in physics and electronics. TIs intrinsically possess both gapless conducting surface and insulating internal properties, instead of being only one property such as conducting, semiconducting, and insulating. The conducting surface state of TIs is the consequence of band inversion induced by strong spin-orbit coupling. Combined with broken inversion symmetry, the surface electronic band structure consists of spin helical Dirac cone, which allows spin of carriers governed by the direction of its momentum, and prohibits backscattering of the carriers. It is called by topological surface states (TSS). In this paper, we investigated the TIs materials and their unique properties and denoted the fabrication method of TIs such as deposition and exfoliation techniques. Since it is hard to observe the TSS, we introduced several specialized analysis tools such as angle-resolved photoemission spectroscopy, spin-momentum locking, and weak antilocalization. Finally, we reviewed the various fields to utilize the unique properties of TIs and summarized research trends of their applications.

• IMMUNE NETWORK
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• 제23권6호
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• pp.48.1-48.21
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• 2023

Mesenchymal stromal/stem cells (MSCs) possess immunoregulatory properties and their regulatory functions represent a potential therapy for acute lung injury (ALI). However, uncertainties remain with respect to defining MSCs-derived immunomodulatory pathways. Therefore, this study aimed to investigate the mechanism underlying the enhanced effect of human recombinant bone morphogenic protein-2 (rhBMP-2) primed ES-MSCs (MSC^BMP2) in promoting Tregs in ALI mice. MSC were preconditioned with 100 ng/ml rhBMP-2 for 24 h, and then administrated to mice by intravenous injection after intratracheal injection of 1 mg/kg LPS. Treating MSCs with rhBMP-2 significantly increased cellular proliferation and migration, and cytokines array reveled that cytokines release by MSC^BMP2 were associated with migration and growth. MSC^BMP2 ameliorated LPS induced lung injury and reduced myeloperoxidase activity and permeability in mice exposed to LPS. Levels of inducible nitric oxide synthase were decreased while levels of total glutathione and superoxide dismutase activity were further increased via inhibition of phosphorylated STAT1 in ALI mice treated with MSC^BMP2. MSC^BMP2 treatment increased the protein level of IDO1, indicating an increase in Treg cells, and Foxp3⁺CD25⁺ Treg of CD4⁺ cells were further increased in ALI mice treated with MSC^BMP2. In co-culture assays with MSCs and RAW264.7 cells, the protein level of IDO1 was further induced in MSC^BMP2. Additionally, cytokine release of IL-10 was enhanced while both IL-6 and TNF-α were further inhibited. In conclusion, these findings suggest that MSC^BMP2 has therapeutic potential to reduce massive inflammation of respiratory diseases by promoting Treg cells.

• 한국군사과학기술학회지
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• 제19권5호
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• pp.669-674
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• 2016

The purpose of this study is to demonstrate the suitability of hydrogen peroxide($H_2O_2$) vapor system for platform interior decontamination. Geobacillus stearothermophilus biological indicator(BI) strips and a field tent were used as a biological simulant and as a simulated platform, respectively. Decontamination was performed based on injection rates and tent sizes with exposure time 60 minutes. We standardized the conditions for the field tent decontamination : 8.0 g/min for $30m^3$($H_2O_2$ vapor concentration of 150~500 ppm, relative humidity of 50 %) and 12.0 g/min for $60m^3$($H_2O_2$ vapor concentration of 250~400 ppm, relative humidity of 55 %). Thus we suggest the system is one of the possible candidates for decontamination of platform interiors.