• 한국의학물리학회:학술대회논문집
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• 한국의학물리학회 2006년도 제33회 추계학술대회 발표논문집
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• pp.107-107
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• 2006

• 전자공학회논문지D
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• 제34D권7호
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• pp.79-87
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• 1997

Untill now, the most well-known cofiguration for waveguide grating router(WGR) is composed of radiative star couplers and arrayed waveguide grating(AWG), which usually suffer form the rdiation loss of around 3dB or more. Therefore, te improved design of WGRs is needed to reduce the loss. In ths paper, we propose a novel WGR composed of multimode interference couplers which have good unifiormity, fabrication tolerance, and very low excess loss, and suggest the efficient algorithm to find the proper path length differences of AWG for given channel spacing and channel assignment to each output prot. The simulated spectral responses of the proposed WGR using the finite difference beam propagation method (BPM) show that the excess loss is less than 0.3dB and the crosstalk less than -25dB in case of 4x4 WGR, and the excess loss less than 0.4dB and the crosstalk less than -25dB in case of 8x8 WGR for all the channel wavelengths.

• Applied Microscopy
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• 제28권4호
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• pp.591-601
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• 1998

The neurotoxic effects of radiation have been studied in NSC-34 hybrid cells derived from embryonic mouse spinal cord cells. NSC-34 cells irradiated at 25Gy were decreased the cell viability in a time and dose dependent manner. The decrease in cell viability induced by the irradiation was blocked by catalase. Antagonists of the N-methyl-D-aspartate (NMDA) receptor, including D-2-amino-5-phosphonovaleric acid (APV) and chlorokynurenic acid (CKA), similarly blocked radiational induced in cell viability. We performed morphological analysis of light and electron microscope. NSC-34 cells irradiated at 25Gy were decreased the cell density and increased lysosomes and vacuoles in the cytoplasm. Especially chromatin modification was observed. These results indicated that radiation was involved in the oxidant-initiated neurotoxicity and the compounds catalase, APV and CKA were shown to be neuroprotective against radiation.

• 태양에너지
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• 제14권2호
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• pp.17-28
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• 1994

최근에 대체에너지사업 수행지역이 확대됨에 따라 월평균 수평면 전일사량을 예측하기 위한 경험적 상수의 산출이 절실히 요구되고 있다. 본 연구는 일사자료가 없는 지역에서 일조율이나 운량 등에 대한 상관관계를 유도하여 회귀모델을 도출하고, 이를 임의의 지역에 대한 일사량에 적용코자 하였다. 본 연구의 결과, 일조율에 의한 방법에 의하여 유도된 상관관계식은 연평균 오차가 $-4{\sim}+2%$ 범위로 나타나 실측치와 상당히 접한 값을 나타내었다.