• 천문학회지
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• 제55권4호
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• pp.87-97
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• 2022

Polarimetric measurements of the lunar surface from lunar orbit soon will be available via Wide-Field Polarimetric Camera (PolCam) onboard the Korea Pathfinder Lunar Orbiter (KPLO), which is planned to be launched in mid 2022. To provide calibration data for the PolCam, we are conducting speckle polarimetric measurements of the nearside of the Moon from the Earth's ground. It appears that speckle imaging of the Moon for scientific purposes has not been attempted before, and there is need for a procedure to create a "lucky image" from a number of observed speckle images. As a first step of obtaining calibration data for the PolCam from the ground, we search for the best sharpness measure for lunar surfaces. We then calculate the minimum number of speckle images and the number of images to be shift-and-added for higher resolution (sharpness) and signal-to-noise ratio.

• Journal of Animal Science and Technology
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• 제46권3호
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• pp.307-314
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• 2004

돼지를 이용한 이종간 장기 이식은 차세대 장기 공급 부족 문제를 해결해 줄 수 있는 가능성을 제공해준다. 그러나 돼지 장기를 이용한 이종간 장기 이식은 면역학적인 문제 외에도 가축 유래 전염성 병원균에 대한 안전성 문제가 심각하게 고려되어지고 있다. 대부분의 외인성 병원균은 무균 사육환경을 통해 제어되는 반면 내인성 레트로 바이러스(Endogenous Retrovirus, PERVs)는 germ line을 통해 전파됨으로 사육 조건으로 해결할 수는 없다. 본 연구는 이종간 장기 이식용 무균 돼지 생산시 가장 문제가 되는 PERVs에 대한 분포를 알아보고자 국내 돼지(Landrace, Berkshire, Yorkshire, Duroc)의 genome 내 PERVs 분포와 유전자 염기 서열을 비교하였다. 모든 공시 돼지(20두)의 genomic DNA로부터 PCR을 이용하여 PERV A/B/C와 PERV-E의 존재를 확인하였다. pol 유전자 일부 염기 서열 분석 결과 같은 품종내 개체간 또는 품종간 상동성이 99.1과 98.8%로 매우 높게 나왔다. 본 연구의 결과 모든 국내 돼지 유전자내에 PERV A/B/C와 PERV E가 provirus 형태로 많이 존재하며 바이러스간의 높은 상동성은 바이러스 제어에 많은 잇점으로 작용하리라 사료되며 아직 밝혀지지 않은 내인성바이러스에 대한 연구가 요구되어진다. 그러므로 본 연구의 자료는 이종간 장기 이식용 무균돼지 생산 시 PERVs 를 제어하기 위한 기초 자료로 활용될 수 있을 것으로 사료된다.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2003년도 오염토양, 지하수 정화사례
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• pp.41-48
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• 2003

• 한국조사연구학회:학술대회논문집
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• 한국조사연구학회 2003년도 춘계학술발표대회
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• pp.216-229
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• 2003

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1994년도 춘계학술발표회 프로그램 및 초록
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• pp.87-88
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• 1994

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 1996년도 추계 학술발표회
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• pp.195-199
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• 1996

• 한국지능시스템학회:학술대회논문집
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• 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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• pp.591-594
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• 2003

In this paper, we propose a method to avoidance obstacle in which we assume that obstacle has an unstable limit cycle in the chaos trajectory surface. In order to avoid the obstacle, we assume that all obstacles in the chaos trajectory surface in which has an unstable limit cycle with Van der Pol equation. In this paper show also that computer simulation results are satisfy to avoid obstacle in the chaos trajectory with Chua's circuit equation of one or multi obstacle has an limit cycle with Van der Pol (VDP) efuation and compare to rate of cover in one robot which have random walk and Chua's equation.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2005년도 종합학술발표회 논문집 Vol.15 No.1
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• pp.143-148
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• 2005

The objective of this study is to estimate RF signal strength over sea and land surfaces. For this work we calculated scattering by land with DEM(Digital Elevation Model) and sea surface with RMS surface height. and we selected two area inland and sea shore as RX point. And for each area, we get VV-pol and HH-pol characteristic of scattering at 2.2GHz.

• Molecules and Cells
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• 제43권10호
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• pp.841-847
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• 2020

Histone acetylation and deacetylation play central roles in the regulation of chromatin structure and transcription by RNA polymerase II (RNA Pol II). Although Hda1 histone deacetylase complex (Hda1C) is known to selectively deacetylate histone H3 and H2B to repress transcription, previous studies have suggested its potential roles in histone H4 deacetylation. Recently, we have shown that Hda1C has two distinct functions in histone deacetylation and transcription. Histone H4-specific deacetylation at highly transcribed genes negatively regulates RNA Pol II elongation and H3 deacetylation at inactive genes fine-tunes the kinetics of gene induction upon environmental changes. Here, we review the recent understandings of transcriptional regulation via histone deacetylation by Hda1C. In addition, we discuss the potential mechanisms for histone substrate switching by Hda1C, depending on transcriptional frequency and activity.

• 미생물학회지
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• 제26권2호
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• pp.113-121
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• 1988

Ozone, an atmospheric pollutant, can damage similar UV and X-rays DNA and its components. It is possible then that the KNA damage produced by this gas are similar, to some extent, to those of radiations and that they could be repaired by the same DNA repair mechanisms. It has been observed in Escherichia coli that radiosensitive strains such as lex A, rec A and pol A, all deficient to some extent for DNA repair, are more sensitive to ozone than a wild type strain. We have thendetermined the ozone resistance and host-cell reactivation of ozone-damaged T3 phages for the E. coli double mutants pol A, lex A, uvr B, lex A, uvr A, rec A and rec A lox A. According to the results, the DNA polymerase 1 plays a key role in ozone resistance and Type 11 mechanism and/or shory patch excision repair are the most important for it. The interactions between the different DNA repair mechanisms are secondary. There is a strong correlation between ozone resistance and the capacity to reactivate T3 phages damaged by ozone.