• KSBB Journal
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• v.17 no.4
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• pp.370-375
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• 2002

Isolation of a gene and determination of its expression pattern are essential in understanding its function. Among the genes localized in 12ql3, stSG3435 EST was chosen to study its expression pattern. The full-length CDNA was cloned by screening of human brain CDNA library and its sequence was determined by serial deletion followed by automated sequencing of the clones with overlapping fragments. The sequence analysis revealed that stSG 3435 CDNA displayed 100% identity to human MYGI and 86% identity to mouse melanocyte proliferation gene-1 (Gamm 1) originally identified from melanocyte, suggesting that MYGI determined by Northern blot analysis revealed the strongest expression in testes with ubiquitous expression in all the tissues tested. In order to investigate the cellular localization of its protein product, the green fluorescence protein gene was fused into the full-length coding sequence of MYGI, Transfection of the fusion construct followed by confocal microscopy resulted in the green fluorescence signal as a punctate state in cytoplasm indication that MYGI was localized in one of the cellular organelles.

• Electronics and Telecommunications Trends
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• v.9 no.3
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• pp.97-102
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• 1994

상호대화형 오디오비주얼 서비스는 텍스트, 도형, 사진, 오디오, 비디오 등과 같은 다양한 형태의 표현 요소로 구성되는 입출력 정보를 사용자의 단말이나 워크스테이션에 제공하는 서비스이다. 이러한 기능의 범위는 간단한 검색에서부터 상호대화적인 문의, 구성요소들의 재배치, 그들 요소들의 수정등의 서비스를 사용자에게 제공 할 수 있다. 이와 관련하여 ITU-T SG8/Q.11에서는 AVI 서비스를 위해 요구되는, 시스템, 데이터 교환형식, 그리고 프로토콜과 같은 일련의 기술적 사항을 표준화하는 작업을 하고 있다. 본고에서는 AVI 서비스의 기술적인 사항에 대하여 논하고, 현재 진행되고 있는 표준화 동향에 대하여 알아본다.

• Electronics and Telecommunications Trends
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• v.8 no.3
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• pp.33-38
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• 1993

본 고는 ITU의 130년 변천과정과 함께 그에 따른 전기통신분야의 발전과정을 살펴본다. 우리나라에서는 1952년 ITU 가입, 1989년 관리이사국 피선, 1993년 ITU-TS SG7 부의장 피선 등의 활동과정이 있었다. 본 고에서는 도한 ITU의 위원회 업무내용과 조직변화에 따른 우리의 대응변화를 제시코저 한다.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.13 no.10
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• pp.4598-4603
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• 2012

The purpose of this study is to compare and evaluate the balance and muscle activity after having performed balance exercise at different ground conditions. The subjects were divided into 3 groups; Sand Group(SG)(N=30) and Balance Form group(BFG)(N=30), Hard Ground Group(HGG)(N=30). The period of intervention was for six weeks. EMG for Tibialis anterior(TA), Soleus(So), Biceps femoris(BF) muscle activity, Air-balance system 3D were used as evaluation tools for this study. the change of balance ability and TA, So muscle activity was greater in the SG, BFG than HGG which may imply that sand can be used for the balance exercise like any other ground.

• Archives of Pharmacal Research
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• v.25 no.4
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• pp.428-432
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• 2002

Three new dammarane glycosides were isolated from the processed ginseng (SG; Sun Ginseng). Their structure were determined to be $3{\beta},{\;}12{\beta}-dihydroxydammar-20(21),24-diene-3-O-{\beta}-D-glucopyranosyl(1{\;}{\rightarrow}{\;}2)-{\beta}-D-glucopyranoside;{\;}3{\beta},{\;}12{\beta}-dihydroxydammar-20(21),24-diene-3-O-{\beta}-D-{\;}glucopyranoside{\;}and{\;}3{\beta},6{\alpha},12{\beta}-trihydroxydammar-20(21),24-diene-6-O-{\beta}-D-glucopyranoside$ based on spectroscopic evidences. The compounds were named as ginsenoside $Rk_1,{\;}Rk_2,{\;}and{\;}Rk_3$ respectively.

• Bulletin of the Korean Chemical Society
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• v.29 no.1
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• pp.177-180
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• 2008

Laser induced fluorescence studies of hydrogen atom using four wave mixing technique are reported for the photodissociation of CH4 and its isotopomers at Lya (121.6 nm). The source of dissociating and probe radiation is one and the same (delay time??20 nsec). The average translational energy of ejected hydrogen atoms (50 Kcal/mol) reveals that CH4 + hn??CH3 + H(2S) and CH4 + hn??CH2(a1A1) + H2(1Sg) are the main dissociation processes. The absolute quantum yield for CH4 and CD4 are the same, FH(CH4) = FD(CD4) = 0.31 0.05. If one divides the experimental H/D ratios from the isotopomers CH3D, CH2D2, CHD3 by the isotopic H/D ratios, a value 2 is obtained in all three cases. Overall, the heavier D atoms are more likely than the H atoms to remain attached to the carbon atom.

• Economic and Environmental Geology
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• v.31 no.2
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• pp.127-139
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• 1998

A new technique of simultaneous inversion for 3-D seismic velocity structure by using direct, reflected, and refracted waves is applied to the southeast part of the Korean Peninsula including Pohang Basin, Kyongsang Basin and Ryongnam Massif. Pg, Sg, PmP, SmS, Pn, and Sn arrival times of 44 events with 554 seismic rays are inverted for locations and crustal structure. $6{\times}6$ with $0.5^{\circ}$ and 8 layers (4 km each layer) model was inverted. 3-D seismic crustal velocity tomography including eight sections from surface to Moho, ten profiles along latitude and longitude are analyzed. The results are as follows: 1) the average velocity and thickness of sediment are 5.04 km/s and 3-4 km, and the velocity of basement is 6.11 km/s. The shape of velocity in shallower layer is agreement with Bouguer gravity anomaly (Cho et al., 1997). 2) the velocities fluctuate strongly in the upper crust. The velocity distribution of the lower crust under Conrad appears basically horizontal. 3) the average depth of Moho is 30.4 km, and velocity is 8.01 km/s. 4) from the velocity and depth of the sediment, the thickness, velocity and form of the upper crust, and the depth and form of Moho, we can find the obvious differences among Ryongnam Massif, Kyongsang Basin and Pohang Basin. 5) the deep faults (a Ulsan series faults) near Kyongju and Pohang areas can be found to be normal and/or thrust faults with detachment extended to the bottom of the upper crust.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.5
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• pp.665-671
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• 2013

In a Korean Generation IV prototype sodium-cooled fast reactor (SFR), various types of high-temperature heat exchangers such as IHX (intermediate heat exchanger), DHX (decay heat exchanger), AHX (air heat exchanger), FHX (finned-tube sodium-to-air heat exchanger), and SG (steam generator) are to be designed and installed. In this study, the high-temperature design and integrity evaluation of the sodium-to-air heat exchanger AHX in the STELLA-1 (sodium integral effect test loop for safety simulation and assessment) test loop already installed at KAERI (Korea Atomic Energy Research Institute) and FHX in the SEFLA (sodium thermal-hydraulic experiment loop for finned-tube sodium-to-air heat exchanger) test loop to be installed at KAERI have been performed. Evaluations of creep-fatigue damage based on full 3D finite element analyses were conducted for the two heat exchangers according to the high-temperature design codes, and the integrity of the high-temperature design of the two heat exchangers was confirmed.

• Speech Sciences
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• v.3
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• pp.71-82
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• 1998

Five sets of nonsense acoustical stimuli {$[sp{\varepsilon},st{\varepsilon},sk{\varepsilon}],\;[p{\varepsilon},t{\varepsilon},k{\varepsilon}],\;[sb{\varepsilon},sd{\varepsilon},sg{\varepsilon}],\;[b{\varepsilon},d{\varepsilon},g{\varepsilon}],\;['{\varepsilon}b{\varepsilon},'{\varepsilon}d{\varepsilon},'{\varepsilon}g{\varepsilon}]$} were presented for identification of English stops to native speakers of English, Chinese, and Korean. The English speakers perceived stops after /s/ as /p, t, k/; in other contexts as /b, d, g/. In the languages where other distinctions exist, however, the evaluation was different. The results suggest that in English the cue for stops after /s/ was syllable structure constraint: After initial /s/ always /p, t, k/ follow; the cue for the initial stops was aspiration. On the basis of the results, it was concluded that in English we should classify the unaspirated voiceless stops in initial /s/-stop clusters into the phoneme where [$p^{h},t^{h},k^{h}$] are in, and that perception is not only language specific but also context specific.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.311-311
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• 2016

최근 고성능 디스플레이 개발이 요구되면서 기존 비정질 실리콘(a-Si)을 대체할 산화물 반도체에 대한 연구 관심이 급증하고 있다. 여러 종류의 산화물 반도체 중 a-IGZO (amorphous indium-gallium-zinc oxide)가 높은 전계효과 이동도, 저온 공정, 넓은 밴드갭으로 인한 투명성 등의 장점을 가지며 가장 연구가 활발하게 보고되고 있다. 기존에는 SG(단일 게이트) TFT가 주로 제작 되었지만 본 연구에서는 DG(이중 게이트) 구조를 적용하여 고성능의 a-IGZO 기반 박막 트랜지스터(TFT)를 구현하였다. SG mode에서는 하나의 게이트가 채널 전체 영역을 제어하지만, double gate mode에서는 상, 하부 두 개의 게이트가 동시에 채널 영역을 제어하기 때문에 채널층의 형성이 빠르게 이루어지고, 이는 TFT 스위칭 속도를 향상시킨다. 또한, 상호 모듈레이션 효과로 인해 S.S(subthreshold swing)값이 낮아질 뿐만 아니라, 상(TG), 하부 게이트(BG) 절연막의 계면 산란 현상이 줄어들기 때문에 이동도가 향상되고 누설전류 감소 및 안정성이 향상되는 효과를 얻을 수 있다. Dual gate mode로 동작을 시키면, TG(BG)에는 일정한 positive(or negative)전압을 인가하면서 BG(TG)에 전압을 가해주게 된다. 이 때, 소자의 채널층은 depletion(or enhancement) mode로 동작하여 다른 전기적인 특성에는 영향을 미치지 않으면서 문턱 전압을 쉽게 조절 할 수 있는 장점도 있다. 제작된 소자는 p-type bulk silicon 위에 thermal SiO2 산화막이 100 nm 형성된 기판을 사용하였다. 표준 RCA 클리닝을 진행한 후 BG 형성을 위해 150 nm 두께의 ITO를 증착하고, BG 절연막으로 두께의 SiO2를 300 nm 증착하였다. 이 후, 채널층 형성을 위하여 50 nm 두께의 a-IGZO를 증착하였고, 소스/드레인(S/D) 전극은 BG와 동일한 조건으로 ITO 100 nm를 증착하였다. TG 절연막은 BG 절연막과 동일한 조건에서 SiO2를 50 nm 증착하였다. TG는 S/D 증착 조건과 동일한 조건에서, 150 nm 두께로 증착 하였다. 전극 물질과, 절연막 물질은 모두 RF magnetron sputter를 이용하여 증착되었고, 또한 모든 patterning 과정은 표준 photolithography, wet etching, lift-off 공정을 통하여 이루어졌다. 후속 열처리 공정으로 퍼니스에서 질소 가스 분위기, $300^{\circ}C$ 온도에서 30 분 동안 진행하였다. 결과적으로 $9.06cm2/V{\cdot}s$, 255.7 mV/dec, $1.8{\times}106$의 전계효과 이동도, S.S, on-off ratio값을 갖는 SG와 비교하여 double gate mode에서는 $51.3cm2/V{\cdot}s$, 110.7 mV/dec, $3.2{\times}108$의 값을 나타내며 훌륭한 전기적 특성을 보였고, dual gate mode에서는 약 5.22의 coupling ratio를 나타내었다. 따라서 산화물 반도체 a-IGZO TFT의 이중게이트 구조는 우수한 전기적 특성을 나타내며 차세대 디스플레이 시장에서 훌륭한 역할을 할 것으로 기대된다.