• 멤브레인
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• 제19권2호
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• pp.129-135
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• 2009

바나듐 레독스-흐름 전지용 격막으로 사용하기 위해 폴리설폰(Psf)에 폴리페닐렌설파이드설폰(PPSS)을 블록 공중합 시킨 폴리머를 사용하여 양이온교환막을 제작하여, 막 특성을 평가하였다. 제작한 양이온교환막은 Nafion117보다 열적 안정성이 뛰어나다는 것을 TG분석을 통해 알 수 있었고, 1몰 황산용액에서의 막 저항은 3 cc의 CSA를 도입하였을 때 $0.96{\Omeg}{\cdot}cm^2$로 제일 작은 저항 값을 나타냈다. 제작한 양이온교환막의 바나듐 레독스-흐름 전지에서의 전기화학적 특성에 대해 평가하였다. 제작한 양이온교환막을 사용한 바나듐 레독스-흐름 전지의 100% 충전상태에서의 기전력은 바나듐 레독스-흐름 전지의 기전력 값인 1.4V를 나타냈으며, 각 충전상태에서의 충 방전 셀 저항은 Nafion117을 사용한 전지의 값보다 작은 값을 나타냈다.

• 천문학회지
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• 제55권2호
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• pp.37-57
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• 2022

Using I-band images of 35 nearby (z < 0.1) type 1 active galactic nuclei (AGNs) obtained with Hubble Space Telescope, selected from the 70-month Swift-BAT X-ray source catalog, we investigate the photometric properties of the host galaxies. With a careful treatment of the point-spread function (PSF) model and imaging decomposition, we robustly measure the I-band brightness and the effective radius of bulges in our sample. Along with black hole (BH) mass estimates from single-epoch spectroscopic data, we present the relation between BH mass and I-band bulge luminosity (M_BH-M_I,bul relation) of our sample AGNs. We find that our sample lies offset from the M_BH-M_I,bul relation of inactive galaxies by 0.4 dex, i.e., at a given bulge luminosity, the BH mass of our sample is systematically smaller than that of inactive galaxies. We also demonstrate that the zero point offset in the M_BH-M_I,bul relation with respect to inactive galaxies is correlated with the Eddington ratio. Based on the Kormendy relation, we find that the mean surface brightness of ellipticals and classical bulges in our sample is comparable to that of normal galaxies, revealing that bulge brightness is not enhanced in our sample. As a result, we conclude that the deviation in the M_BH-M_I,bul relation from inactive galaxies is possibly because the scaling factor in the virial BH mass estimator depends on the Eddington ratio.

• Current Optics and Photonics
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• 제6권2호
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• pp.171-182
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• 2022

A single-photon laser and mid-wave infrared (MWIR) common aperture optical system was designed and developed to detect and range a long-distance civil aviation aircraft. The secondary mirror of the Ritchey-Chretien (R-C) optical system was chosen as a dichroic lens to realize the design of a common aperture system for the laser and MWIR. Point spread function (PSF) ellipticity was introduced to evaluate the coupling efficiency of the laser receiving system. A small aperture stop and narrow filter were set in the secondary image plane and an afocal light path of the laser system, respectively, and the stray light suppression ability of the small aperture stop was verified by modeling and simulation. With high-precision manufacturing technology by single point diamond turning (SPDT) and a high-efficiency dichroic coating, the laser/MWIR common aperture optical system with a 𝜑300 mm aluminum alloy mirror obtained images of buildings at a distance of 5 km with great quality. A civil aviation aircraft detection experiment was conducted. The results show that the common aperture system could detect and track long-distance civil aviation aircraft effectively, and the coverage was more than 450 km (signal-to-noise ratio = 6.3). It satisfied the application requirements for earlier warning and ranging of long-range targets in the area of aviation, aerospace and ground detection systems.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2022년도 추계학술대회
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• pp.143-143
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• 2022

Plant defense systems against pathogens have been studied extensively and are currently a hot topic in plant science. Using a reverse genetics technique, this study looked into the involvement of the NO-downregulated NAD(P)-binding Rossmann-fold superfamily gene in plant growth and defense in Arabidopsis thaliana. For this purpose, the knockout and overexpressing plant of the candidate gene along with the relevant controls were exposed to control, oxidative and nitro-oxidative stresses. The results showed that candidate gene negatively regulates plants' root and shoot lengths. To investigate the role of the candidate gene in plant basal defense, R-gene-mediated resistance and systemic acquired resistance (SAR) plants were challenged with virulent or avirulent strains of Pseudomonas syringae pathovar tomato (Psf) DC3000. The results showed that the candidate gene negatively regulates plants' basal defense, R-gene-mediated resistance and SAR. Further characterization via GO analysis associated the candidate gene with metabolic and cellular processes and response to light stimulus, nucleotide binding and cellular location in the cytosol and nucleus. Protein structure analysis indicated the presence of a canonical Oxidoreductase family NAD (P)-binding Rossmann fold domain of 120 amino acids with a total of 121 plant homologs across 35 different plant species in the clad streptophyta. Arabidopsis eFP browser showed its expression in almost all the above-ground parts. Protein analysis indicated C225 and C359 as potential targets for S-Nitrosylation by NO. SMART analysis indicated possible interactions with mevalonate/galactokinase, galacturonic acid kinase, arabinose kinase, putative xylulose kinase, GroES-like zinc-binding alcohol dehydrogenase and various glyceraldehyde-3-phosphate dehydrogenases.

• 한국지구과학회지
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• 제36권7호
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• pp.661-673
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• 2015

우즈베키스탄 Maidanak 천문대 AZT-22 1.5 m 망원경(f/7.74)과 SITe $2000{\times}800$CCD를 사용하여 3개의 ${\delta}$ Cep 변광성 CEa Cas, CEb Cas 및 CF Cas가 있는 중년 산개성단 NGC 7790의 UBVI 측광 관측을 수행하였다. 관측자료는 IRAF/DAOPHOT를 이용하여 PSF 측광을 수행하였으며, V와 I 필터에서 모두 측광된 별의 수는 총 1008개이며, 측광의 한계등급은 $V{\approx}22$등급이다. 대기소광계수 및 측광영점을 결정하기 위하여 천구적도에 있는 여러 표준별과 청색 및 적색 표준별을 다양한 대기투과량에서 관측하였다. 표준별 측광을 통해 대기소광계수 및 측광영점을 결정하고, 성단의 측광자료는 Johnson-Cousins UBVI 표준계로 변환하였다. NGC 7790의 UBVI 색-등급도와 색-색도에서 이 성단의 B와 V 필터에서의 색초과량 [$E(B-V)=0.58{\pm}0.02$], B와 V 필터에서의 선택적 소광량 [$R_V{{\equiv}}A_V/E(B-V)=3.02{\pm}0.09$] 및 거리지수($V_0-M_V=12.65{\pm}0.10$)를 얻었다. H-R도에서 세페이드 변광성의 위치를 고려하여 나이를 결정하였다. 이 과정에서 Padova 연구집단(Bressan et al., 2012)의 등연령곡선(Z=0.019)과 Geneva 연구집단($Ekstr{\ddot{o}}m$ et al., 2012)의 등연령곡선(Z=0.014)을 모두 사용하였고, 그중에서 자전을 고려한 Geneva 연구집단의 진화모형이 관측자료와 잘 일치하여 NGC 7790의 나이로 log $age=8.05{\pm}0.05$ [yr]를 얻었다. 또 NGC 7790내 세페이드 변광성의 절대등급은 세페이드 변광성의 평균 주기-광도 관계에 비해 분산 범위 내에 있기는 하지만 주어진 주기에서 평균적으로 약 0.5등급 정도 밝음을 확인하였다.

• 한국안전학회지
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• 제35권1호
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• pp.87-96
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• 2020

The purpose of this paper is to develop a fire HRA (Human Reliability Analysis) procedure for full power operation of domestic NPPs (Nuclear Power Plants). For the development of fire HRA procedure, the recent research results of NUREG-1921 in an effort to meet the requirements of the ASME/ANS PRA Standard were reviewed. The K-HRA method, a standard method for HRA of a domestic level 1 PSA (Probabilistic Safety Assessment) and fire related procedures in domestic NPPs were reviewed. Based on the review, a procedure for the fire HRA required for a domestic fire PSA based on the K-HRA method was developed. To this end, HRA issues such as new operator actions required in the event of a fire and complexity of fire situations were considered. Based on the four kinds of HFE (Human Failure Event) developed for a fire HRA in this research, a qualitative analysis such as feasibility evaluation was suggested. And also a quantitative analysis process which consists of screening analysis and detailed analysis was proposed. For the qualitative analysis, a screening analysis by NUREG-1921 was used. In this research, the screening criteria for the screening analysis was modified to reduce vague description and to reflect recent experimental results. For a detailed analysis, the K-HRA method and scoping analysis by NUREG-1921 were adopted. To apply K-HRA to fire HRA for quantification, efforts to modify PSFs (Performance Shaping Factors) of K-HRA to reflect fire situation and effects were made. For example, an absence of STA (Shift Technical Advisor) to command a fire brigade at a fire area is considered and the absence time should be reflected for a HEP (Human Error Probability) quantification. Based on the fire HRA procedure developed in this paper, a case study for HEP quantification such as a screening analysis and detailed analysis with the modified K-HRA was performed. It is expected that the HRA procedure suggested in this paper will be utilized for fire PSA for domestic NPPs as it is the first attempt to establish an HRA process considering fire effects.

• 멤브레인
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• 제28권2호
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• pp.121-128
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• 2018

세 가지의 다른 화학 성분으로 구성된 터폴리머는 기체분리막에 거의 활용되지 못하였다. 본 연구에서는 poly(2-[3-(2H-Benzotriazol-2-yl)-4-hydroxyphenyl] ethylmethacrylate)(PBEM), poly(oxyethylene methacrylate)(POEM), methyl methacrylate (MMA)로 구성된 터폴리머를 자유라디칼 중합법으로 합성하였고, 이를 기반으로 하여 이산화탄소/질소 분리를 위한 복합막 제조 공정을 개발하였다. 합성된 PBEM-PMMA-POEM 용액을 다공성 폴리설폰 지지체위에 코팅하여 복합막을 제조하였다. 성공적인 중합, 특성 및 구조분석을 위하여 푸리에 변환 적외선 분광학, X-ray 회절분석법, 열중량 분석 및 전계방사 주사전자 현미경을 사용하였다. PBEM-PMMA-POEM 터폴리머 분리막의 기체 투과도 및 이산화탄소/질소 선택도를 $25^{\circ}C$에서 측정하였다. 최고의 이산화탄소/질소 선택도는 30.2에 도달하였으며, 이산화탄소 투과도는 57.4 GPU ($1GPU=10^{-6}cm^3$(STP)/($s\;cm^2\;cmHg$))이었다.

• 한국방사성폐기물학회:학술대회논문집
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• 한국방사성폐기물학회 2004년도 학술논문집
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• pp.97-104
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• 2004

원자력시설의 해체를 위한 표면오염도를 측정함에 있어 기존의 일반적인 단일층 함침 복합체의 단점을 개선한 치밀한 구조의 지지층 위에 활성층의 2차막을 도포 하여 제조된 이중 구조의 고분자 복합체를 제조하고 이들의 특성을 분석하였다. 세륨활성화된 이트리움실리케이트(Cerium-activated ytttrium silicate, CAYS)를 함침시킨 폴리설폰 이중구조 필름은 1차 지지층으로서 폴리설폰 (polysulfone, PSF)과 메틸렌클로라이드 (methylene chloride, MC)로 이루어진 2액용액을 유리판 위에 제막하고 증발을 통해 MC를 제거하여 고분자의 유리화(vitrification)를 통해 치밀한 구조로 고형화하도록 하였다. 고형화한 1차층 위에 CAYS 와 용매로 이루어진 2차 제막용액을 덧붙여 도포하고 물에 침지시키거나 대기방치를 통해 고형화시켰다. 이렇게 이루어진 2중 구조의 무기섬광체 함침 복합체 필름은 2차 제막층에 손가락 형태의 큰 기공이 생성되었으며, 1차층과 2차층이 완전히 결합되어 있어 우수한 기계적 물성을 나타냈다. 한편, 섬광체인 CAYS를 첨가하였을 때 필름에 생성되는 은 기공의 형성이 증대되는 특성을 보였으며, 용매의 증발에 의해 고형화 된 필름은 치밀한 구조의 형상을 보였다. 제조된 필름들은 방사성핵종의 탐지에 있어 신뢰할만한 탐지 결과를 보였다.

• 천문학회보
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• 제38권2호
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• pp.71.1-71.1
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• 2013

Among quadruples or higher multiplicity stars, only a few binary systems have been discovered. They are important targets to understand the formation and evolution of multiple stellar systems because we can obtain accurate stellar parameters from photometric and spectroscopic studies. We present the observational results of this kind of rare object 1SWASP J093010.78+533859.5, for which the doubly eclipsing feature had been detected previously from the SuperWASP photometric archive. Individual PSF photometry for two objects with a separation of about 1.9 arcsec was performed for the first time in this study. Our time-series photometric data show that the brighter object A is an Algol-type detached eclipsing binary with an orbital period of 1.3 days and the fainter B is a W UMa-type contact eclipsing binary with a period of 0.23 days. Using the high-resolution optical spectra, we obtained well-defined radial velocity variations of the system A. Furthermore, stationary spectral lines were detected and should have originated from the other stellar component, which was confirmed by the third object contribution from the light curve analysis. No spectral feature of the system B was detected, probably due to its faintness. We obtained the binary parameters and the absolute dimensions from each light curve synthesis. The primary and secondary components of the system A have a spectral type of K1 and K5 main sequences, respectively. Two components of system B have nearly the same type of K3 main sequence. Light variations at out of eclipses were appeared in both systems, interpreting as the effect of stellar spots on these late spectral type stars. We estimated the distances to the systems A and B individually. They may have similar distances of about 70 pc and seem to be gravitationally bound with a separation of about 130 AU. In conclusion, we suggest that 1SWASP J093010.78+533859.5 is a quintuple stellar system with a hierarchical structure of a triple system A(ab)c and a binary system B(ab).

• 한국안광학회지
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• 제21권3호
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• pp.281-288
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• 2016

목적: 중심장액성맥락망막병증을 치료 중인 눈과 완치된 눈의 광학적 질의 변화를 알아보았다. 방법: 총 68명 136안을 대상으로 중심장액성맥락망막병증을 치료 중인 눈 및 무증상 반대편 눈, 중심장액성맥락망막병증을 진단받은 후 완치된 눈 및 반대편 눈과 정상인 눈의 객관적 산란지수, 변조전달함수 값, 상의 집속률, 점상강도 분포함수 50%폭과 10% 폭 및 대비감도를 측정하여 분석하였다. 결과: 중심장액성맥락망막병증을 치료 중인 눈은 반대편 무증상 눈, 질환이 완치된 눈 및 정상 눈과 비교하여 모든 광학적 질 평가에서 통계적으로 유의하게 광학적 질의 저하가 나타났다. 중심장액성맥락망막병증을 치료 중인 반대편 무증상 눈과 완치된 눈의 경우는 통계적으로 유의하지는 않았지만 정상안보다 광학적 질의 저하 경향이 나타났다. 결론: 본 연구를 통하여 중심장액성맥락망막병증 치료 단계에 따라 광학적인 질에 차이가 있음을 밝혔으며, 중심장액성맥락망막병증의 완치 판정 및 예후 평가에서 광학적 질의 평가의 활용을 제안한다.