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Cytogenetic Analysis of Spotty Belly Greenling (Hexagrammos agrammus) and Greenling (H. otakii) (노래미 (Hexagrammos agrammus)와 쥐노래미 (H. otakii)의 세포유전학적 연구)

  • Sim Mi A;Noh Jae Koo;Nam Yoon Kwon;Kim Dong Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.35 no.6
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    • pp.682-685
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    • 2002
  • Cytogenetic analysis was conducted to obtaining informations for genetic improvement of spotty belly greenling (Hexagrmmos agrammus) and greenling (H. otakii) in aquaculture. Erythrocytes of spotty belly greenling were slightly larger than those of greenling (p<0.05). The nuclear volume of spotty belly greening erythrocytes averaged 15.14 $\pm$ 0.92 ${\mu}m^3$ while that of greening averaged 14.61 $\pm$ 0.15 $\mu$m^3 the difference was not significant (p>0.05). Consequently, genome size of spotty belly greenling was also slightly larger than those of greenling. DNA content per cell of spotty belly greenling and greenling were 2.15 pg and 2.10 pg, respectively. The modal chromosome number of both greenling species were same as 2n=48 and karyotypes were also identical as 2 metacentrics, 11 snbrnetacentrics and 11 acrocentric pairs $(W: 74), There was no evidence of polymorphism including aneuploidy or sex-related heterornorphisrn for all specimens examined. The nuclear organizer regions (NOR_s)$ were localized on a small acrocentric chromosome pair in both species, Spotty belly greenling showed large sizes of active rRNA coding regions in their chromosomes. However, greenling examined only small sizes of active rRNA coding regions with dimorphism.

Structural Capacity Evaluation of System Scaffolding using X-Type Advanced Guardrail (교차가새형 선행 안전난간을 적용한 시스템비계의 구조 성능 평가)

  • Park, J.D.;Lee, H.S.;Shin, W.S.;Kwon, Y.J.;Park, S.E.;Yang, S.S.;Jung, K.
    • Journal of the Korean Society of Safety
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    • v.35 no.5
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    • pp.49-58
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    • 2020
  • In domestic construction sites, when installing steel pipe scaffolding and system scaffolding, the guardrails are installed after the installation of the work platforms. This conventional guardrail system (CGS) is always exposed to the risk of falls because the safety railing is installed later. In order to prevent fall disasters during erecting and dismantling scaffolds, it is necessary to introduce the advanced guardrail system (AGS) which installs railings in advance of climbing onto a work platform. For the introduction of the AGS, the structural performance of the system scaffolding applying the CGS and the AGS was compared and evaluated. The structural analysis of the system scaffold (height: 31 m and width: 27.4 m) with AGS confirmed that structural safety was ensured because the maximum stress of each element of the system scaffolding satisfies the allowable stress of each element. As a result of performance comparison of CGS and AGS for each element, the combined stress ratio of vertical posts in AGS was 6.4% lower than that of CGS. In addition, in the case of ledger and transom, the combined stress ratios of AGS and CGS were almost the same. The compression test of the assembled system scaffolding (three-storied, 1 bay) showed that the AGS had better performance than the CGS by 9.7% (8.91 kN). The cross bracing exceeds the limit on slenderness ratio of codes for structural steel design. But the safety factor for the compressive load of the cross bracing was evaluated as meeting the design criteria by securing 3 or more. In actual experiments, it was confirmed that brace buckling did not occur even though the overall scaffold was buckled. Therefore, in the case of temporary structures, it was proposed to revise the standards for limiting on slenderness ratio of secondary or auxiliary elements to recommendations. This study can be used as basic data for the introduction of AGS for installing guardrails in advance at domestic construction sites.

Vacuum ultraviolet emission characteristics of binary and ternary gas mixtures with xenon concentration and gas pressure in AC-PDPs (AC-PDP에서 Ne-Xe의 2원 혼합기체와 He-Ne-Xe의 3원 혼합기체의 Xe 혼합비와 가스 압력에 따른 VUV 발광 특성)

  • Yoo, N.L.;Jung, K.B.;Lee, J.H.;Lee, S.B.;Han, Y.K.;Jeong, S.H.;Lee, H.J.;Son, C.G.;Lim, J.E.;Oh, P.Y.;Moon, M.W.;Jeoung, J.M.;Ko, B.D.;Cho, G.S.;Uhm, H.S.;Choi, E.H.
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 2005.05a
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    • pp.142-145
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    • 2005
  • AC-PDP에서 발광 휘도와 발광 효율의 개선은 매우 중요한 과제중의 하나이다. 높은 발광 휘도와 발광 효율을 위해선 VUV의 높은 발광 효율이 요구되어진다. 이 실험에서는 AC-PDP에서 Ne-Xe의 2원 혼합기체와 He-Ne-Xe의 3원 혼합기체의 VUV 발광 세기를 측정하였다. 기체 압력은 200 Torr, 300 Torr, 400 Torr, 500 Torr로 유지하였고, Xe 혼합비는 1%, 2%, 4%, 7%, 10%, 15%를 사용하였다. 진공자외선 발광 세기는 He-Ne-Xe의 3원 혼합기체가 Ne-Xe의 2원 혼합기체보다 발광 세기가 훨씬 높다는 것을 알 수 있었다. 그리고 Xe 함량이 증가함에 따라 공명선인 147 nm의 발광 세기는 Xe 혼합비가 약 10%까지는 증가하다가 10% 이후에는 포화되고, 반면 분자선인 173 nm은 Xe 함량과 가스 압력이 증가함에 따라 발광 세기가 증가하였다.

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Effects of Oryza sativa L. Aleurone Layer Extract on Bone Mineral Density and Bone-related Markers in the Ovariectomized Rat (흑미(Oryza sativa L.) 호분층 추출물이 난소절제 흰쥐의 골밀도 및 골대사 지표에 미치는 영향)

  • Nam, Song-Yee;Kim, Nam-Seok;Lee, Young-Min;Choi, Bong-Kyoum;Lee, Seon-Hye;Jang, Hwan-Hee;Kim, Jung-Bong;Lee, Hae-Jeung;Lee, Sung-Joon;Lee, Sung-Hyeon
    • Korean Journal of Pharmacognosy
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    • v.46 no.2
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    • pp.167-172
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    • 2015
  • Aleurone layer of Black rice (Oryza sativa L.) is enriched with anthocyanin that could increase bone density. This study was conducted to investigate the osteoporosis-preventing effects of the aleurone layer extract (BRE) on bone loss of ovariectomized (OVX) rats. OVX (or sham-operated) rats were assigned to three groups (n=8 per group): sham operated group (Sham); OVX control group (OVX); OVX-BRE group, OVX rats treated with BRE at 90 mg/kg B.W. The deionized water alone or deionized water with BRE was orally administrated to Sham, OVX or OVX-BRE groups, respectively for 12 weeks. High fat diet with 45 kcal% fat and water were fed to all rats ad libitum. Body weight was significantly decreased in the OVXBRE group compared to the OVX group (p<0.05). The bone mineral density and bone length of tibia were significantly higher in the OVX-BRE group compared to the OVX group and breaking force was significantly higher for the both tibia and femur bones. Serum estradiol concentration and calcium concentration of femur were higher in the OVX-BRE group than those of OVX group. However, serum alkaline phosphatase activity and parathyroid hormone concentration were decreased in the OVXBRE group compared to the OVX group. The results suggest that aleurone layer of Black rice is a potentially useful ingredient to protect against estrogen deficiency or menopause related osteoporosis.

CMOS 소자 응용을 위한 Plasma doping과 Silicide 형성

  • Choe, Jang-Hun;Do, Seung-U;Seo, Yeong-Ho;Lee, Yong-Hyeon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.456-456
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    • 2010
  • CMOS 소자가 서브마이크론($0.1\;{\mu}m$) 이하로 스케일다운 되면서 단채널 효과(short channel effect), 게이트 산화막(gate oxide)의 누설전류(leakage current)의 증가와 높은 직렬저항(series resistance) 등의 문제가 발생한다. CMOS 소자의 구동전류(drive current)를 높이고, 단채널 효과를 줄이기 위한 가장 효율적인 방법은 소스 및 드레인의 얕은 접합(shallow junction) 형성과 직렬 저항을 줄이는 것이다. 플라즈마 도핑 방법은 플라즈마 밀도 컨트롤, 주입 바이어스 전압 조절 등을 통해 저 에너지 이온주입법보다 기판 손상 및 표면 결함의 생성을 억제하면서 고농도로 얕은 접합을 형성할 수 있다. 그리고 얕은 접합을 형성하기 위해 주입된 불순물의 활성화와 확산을 위해 후속 열처리 공정은 높은 온도에서 짧은 시간 열처리하여 불순물 물질의 활성화를 높여주면서 열처리로 인한 접합 깊이를 얕게 해야 한다. 그러나 접합의 깊이가 줄어듦에 따라서 소스 및 드레인의 표면 저항(sheet resistance)과 접촉저항(contact resistance)이 급격하게 증가하는 문제점이 있다. 이러한 표면저항과 접촉저항을 줄이기 위한 방안으로 실리사이드 박막(silicide thin film)을 형성하는 방법이 사용되고 있다. 본 논문에서는 (100) p-type 웨이퍼 He(90 %) 가스로 희석된 $PH_3$(10 %) 가스를 사용하여 플라즈마 도핑을 실시하였다. 10 mTorr의 압력에서 200 W RF 파워를 인가하여 플라즈마를 생성하였고 도핑은 바이어스 전압 -1 kV에서 60 초 동안 실시하였다. 얕은 접합을 형성하기 위한 불순물의 활성화는 ArF(193 nm) excimer laser를 통해 $460\;mJ/cm^2$의 에니지로 열처리를 실시하였다. 그리고 낮은 접촉비저항과 표면저항을 얻기 위해 metal sputter를 통해 TiN/Ti를 $800/400\;{\AA}$ 증착하고 metal RTP를 사용하여 실리사이드 형성 온도를 $650{\sim}800^{\circ}C$까지 60 초 동안 열처리를 실시하여 $TiSi_2$ 박막을 형성하였다. 그리고 $TiSi_2$의 두께를 측정하기 위해 TEM(Transmission Electron Microscopy)을 측정하였다. 화학적 결합상태를 분석하기 위해 XPS(X-ray photoelectronic)와 XRD(X-ray diffraction)를 측정하였다. 접촉비저항, 접촉저항과 표면저항을 분석하기 위해 TLM(Transfer Length Method) 패턴을 제작하여 I-V 특성을 측정하였다. TEM 측정결과 $TiSi_2$의 두께는 약 $580{\AA}$ 정도이고 morphology는 안정적이고 실리사이드 집괴 현상은 발견되지 않았다. XPS와 XRD 분석결과 실리사이드 형성 온도가 $700^{\circ}C$에서 C54 형태의 $TiSi_2$ 박막이 형성되었고 가장 낮은 접촉비저항과 접촉저항 값을 가진다.

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고효율 태양전지를 위한 ICP-RIE기반 결정질 실리콘 표면 Texturing 공정연구

  • Lee, Myeong-Bok;Lee, Byeong-Chan;Park, Gwang-Muk;Jeong, Ji-Hui;Yun, Gyeong-Sik
    • Proceedings of the Korean Vacuum Society Conference
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    • 2010.02a
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    • pp.315-315
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    • 2010
  • 결정질 실리콘을 포함하는 태양전지의 광전효율은 표면에 입사되는 태양광의 반사를 제외하면 흡수된 광자에 의해 생성되는 전자-정공쌍의 상대적인 비율인 내부양자효율에 의존하게 된다. 실제 생성된 전자-정공쌍은 기판재료의 결정상태와 전기광학적 물성 등에 의해 일부가 재결합되어 2차적인 광자의 생성이나 열로서 작용하고 최종적으로 전자와 정공이 완전히 분리되고 전극에 포집되어 실질적인 유효전류로 작용한다. 16% 이상의 고효율 결정질 실리콘 태양전지양산이 요구되고 있는 현실에서 광전효율 개선 위해 가장 우선적으로 고려되어야 할 변수는 입력 태양광스펙트럼에 대한 결정질 실리콘 표면반사율을 최소화하여 광흡수를 극대화하는 것이라 할 수 있다. 이의 해결을 위하여 대기와 실리콘표면 사이의 굴절률차이가 크면 클수록 태양광스펙트럼에 대한 결정질 실리콘의 광반사는 증가하기 때문에 상대적으로 낮은 굴절률의 $SiO_x$$SiN_x$와 같은 반사방지막을 광입력 실리콘표면에 증착하여 광반사율 저감공정을 적용하고 있다. 이와 더불어 결정질 실리콘표면을 화학적으로 혹은 플라즈마이온으로 50-100nm 직경의 바늘형 피라미드형상으로 texturing 함으로 광자들의 다중반사 등에 기인하는 광흡수율의 증가를 기대할 수 있기 때문에 태양전지효율 개선에 긍정적인 영향을 미치는 것으로 이해된다. 본 실험에서도 고효율 다결정 실리콘 태양전지 양산공정에 적용 가능한 ICP-RIE기반 결정질 실리콘표면에 대한 texturing 공정기술을 연구하였다. Double Langmuir 플라즈마 진단시스템(DLP2000)을 적용하여 사용한 $SF_6$$O_2$ 개스유량과 챔버압력, 플라즈마 파워에 따른 이온밀도, 전자온도, 포화이온전류밀도, 플라즈마포텐셜의 공간분포를 모니터링하였고 texturing이 완료된 시료에 대하여 A1.5G 표준태양광스펙트럼의 300-1100nm 파장대역에서 반사율을 측정하여 그 변화를 관찰하였다. 본 연구에서 얻어진 결과를 간략히 정리하면 Si texturing에 가장 적합한 플라즈마파워는 100W, $SF_6/O_2$ 혼합비는 18:22, 챔버압력은 30mtorr 등이고 이에 상응하는 플라즈마의 이온밀도는 $2{\sim}3{\times}10^8\;ions/cm^3$, 전자온도는 14~15eV, 포화전류밀도는 $0.014{\sim}0.015mA/cm^2$, 플라즈마포텐셜은 38~39V 범위 등이었다. 현재까지 얻어진 최소 평균반사율은 14.2% 였으며 최적의 texturing패턴 플라즈마공정 조건은 이온에 의한 Si표면원자들의 스퍼터링과 화학반응에 의한 증착이 교차하는 플라즈마 에너지 및 밀도 상태인 것으로 해석된다.

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Rapid prenatal diagnosis of spinocerebellar ataxia type 3 by using fluorescent PCR

  • Kim, Do-Jin;Park, So-Yeon;Kim, Mi-Jin;Lee, Moon-Hee;Shim, Sung-Han;Ryu, Hyun-Mee
    • Journal of Genetic Medicine
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    • v.4 no.1
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    • pp.84-87
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    • 2007
  • Spinocerebellar Ataxia Type 3 (SCA 3) is a rare autosomal dominative disorder in which one of the neurodegenerative disorders is caused by a CAG repeat expansion on chromosome 14q32.1. The age at onset of disease is related to the size of the expanded CAG repeat. We present the prenatal diagnosis of SCA3 in a woman whose husband was known to carry an unstable CAG repeat expansion in the MJD gene. The diagnosis was made using PCR with a fluorescent probe for an expanded MJD allele. The normal ranges of (CAG)n of SCA3 are 14~38 repeats. The husband, who had a family history of SCA 3, has an expanded allele of 69 CAG repeats with a normal allele of 27 repeats. His wife had two normal alleles with 26 and 32 CAG repeats. The fetus had two normal alleles with 26 and 27 CAG repeats; consequently, the baby w as healthy. We report a case of prenatal diagnosis of SCA3 using a fluorescent PCR which is rapid and accurate.

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Studies of Annealing Effect on the Properties of the Rigid Polyurethane (열처리에 따른 경질 폴리우레탄의 물성 변화 연구)

  • Kang S. J.;Jung H. C.;Kim W. N.;Lee Y. B.;Choe K. H.;Hong S. H.;Kim S. B.
    • Journal of the Korean Institute of Gas
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    • v.2 no.4
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    • pp.18-24
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    • 1998
  • Polyurethane (PU) synthesized from 4,4'-diphenylmethane diisocyanate having high functionality (f=2.9) and polyester polyol have been investigated by differential scanning calorimeter (DSC), dynamic mechanical thermal analyzer (DMTA), and Fourier transform infrared spectroscope (FT-IR). From the DSC measurement of polyurethane, a single transition temperature ($T_g$) was observed. This result indicates that polyurethanes synthesized in this work have homogeneous network structure due to high functionality of diisocyanate. It was also found that the $T_g$ of polyurethane was increased as hard segment content was increased. The results from DMTA measurement are consistent with DSC results. In order to investigate the effect of thermal annealing on the $T_g$ of polyurethane, the samples were annealed at various annealing conditions. $T_gs$ of polyurethanes were found to increased with annealing temperature. From swelling experiment and FT-IR studies, it was found that the $T_g$ was increased as crosslinking density of polyurethane was increased.

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Basin modelling with a MATLAB-based program, BasinVis 2.0: A case study on the southern Vienna Basin, Austria (MATLAB 기반의 프로그램 BasinVis 2.0을 이용한 분지 모델링: 오스트리아 비엔나 분지의 남부 지역에 대한 사례 연구)

  • Lee, Eun Young;Wagreich, Michael
    • Journal of the Geological Society of Korea
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    • v.54 no.6
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    • pp.615-630
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    • 2018
  • Basin analysis is a research field to understand the formation and evolution of sedimentary basins. This task requires various geoscientific datasets as well as numerical and graphical modelling techniques to synthesize results dimensionally in time and space. For basin analysis and modelling in a comprehensive workflow, BasinVis 1.0 was released as a MATLAB-based program in 2016, and recently the software has been extended to BasinVis 2.0, with new functions and revised user-interface. As a case study, this work analyses the southern Vienna Basin and visualizes the sedimentation setting and subsidence evolution to introduce the basin modelling functions of BasinVis 2.0. This is a preliminary study for a basin-scale modelling of the Vienna Basin, together with our previous studies using BasinVis 1.0. In the study area, during the late Early Miocene, sedimentation and subsidence are significant along strike-slip and en-echelon listric normal faults. From the Middle Miocene onwards, however, subsidence decreases abruptly over the area and this situation continues until the Late Miocene. This is related to the development of the pull-apart system and corresponds to the episodic tectonic subsidence in strike-slip basins. The subsidence of the Middle Miocene is confined mainly to areas along the strike-slip faults, while, from the late Middle Miocene, the depocenter shifts to a depression along the N-S trending listric normal faults. This corresponds to the regional paleostress regime transitioning from NE-SW trending transtension to E-W trending extension. This study applies various functions and techniques to this case study, and the modelled results demonstrate that BasinVis 2.0 is effective and applicable to the basin modelling.

Development of Korea Ocean Satellite Center (KOSC): System Design on Reception, Processing and Distribution of Geostationary Ocean Color Imager (GOCI) Data (해양위성센터 구축: 통신해양기상위성 해색센서(GOCI) 자료의 수신, 처리, 배포 시스템 설계)

  • Yang, Chan-Su;Cho, Seong-Ick;Han, Hee-Jeong;Yoon, Sok;Kwak, Ki-Yong;Yhn, Yu-Whan
    • Korean Journal of Remote Sensing
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    • v.23 no.2
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    • pp.137-144
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    • 2007
  • In KORDI (Korea Ocean Research and Development Institute), the KOSC (Korea Ocean Satellite Center) construction project is being prepared for acquisition, processing and distribution of sensor data via L-band from GOCI (Geostationary Ocean Color Imager) instrument which is loaded on COMS (Communication, Ocean and Meteorological Satellite); it will be launched in 2008. Ansan (the headquarter of KORDI) has been selected for the location of KOSC between 5 proposed sites, because it has the best condition to receive radio wave. The data acquisition system is classified into antenna and RF. Antenna is designed to be $\phi$ 9m cassegrain antenna which has 19.35 G/T$(dB/^{\circ}K)$ at 1.67GHz. RF module is divided into LNA (low noise amplifier) and down converter, those are designed to send only horizontal polarization to modem. The existing building is re-designed and arranged for the KOSC operation concept; computing room, board of electricity, data processing room, operation room. Hardware and network facilities have been designed to adapt for efficiency of each functions. The distribution system which is one of the most important systems will be constructed mainly on the internet. and it is also being considered constructing outer data distribution system as a web hosting service for offering received data to user less than an hour.