• 한국생물물리학회:학술대회논문집
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• 한국생물물리학회 1996년도 정기총회 및 학술발표회
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• pp.24-24
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• 1996

SecA protein of E. coli is essential for the translocation of various precursor proteins across the plasma membrane. Along with it, SecA protein interacts with precursor proteins, SecY/E, SecB and is an ATPase which has multiple ATP binding sites. There is little known about the regulation mechanism of the protein translocation machinery. (omitted)

• 한국콘텐츠학회:학술대회논문집
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• 한국콘텐츠학회 2005년도 춘계 종합학술대회 논문집
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• pp.156-164
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• 2005

Fin 수영 선수의 등속성 근 기능을 분석하여 선수 선발 및 트레이닝에 활용하기 위하여 fin 수영 선수군과 일반 수영 선수군의 족부, 요부 및 견감부의 등속성 근 기능을 비교 분석한 결과 다음과 같은 결론을 얻었다. 1) 족관절의 족저굴곡력은 좌 우측의 각 속도 $30^{\circ}/sec$와 $180^{\circ}/sec$에서는 두 집단간에 유의한 차이가 각각 나타났다. 그러나, 두 집단 모두 좌 우측간에는 유의한 차이를 보이지 않았다. 2) 족관절의 족배굴곡력은 우측의 각 속도 $30^{\circ}/sec$에서 두 집단간에 유의한 차이를 보였다. 3) 요부의 신전근력은 각 속도 $60^{\circ}/sec$에서 두 집단간에 유의한 차이를 보였다. 4) 견갑부의 굴곡근력은 우측의 각 속도 $60^{\circ}/sec$와 $180^{\circ}/sec$에서 두 집단간에 유의한 차이를 보였다. 또한, 수영집단의 굴곡근력은 각 속도 $60^{\circ}/sec$와 $180^{\circ}/sec$에서 좌 우측간에 유의한 차이를 보였다. 이러한 결과를 살펴볼 때 fin 수영군은 족부와 요부에 유의하게 높은 등속성 근 기능을 보이고 있어 선수 선발 및 이들 부위의 근 기능을 강화시킬 수 있는 트레이닝 방법을 적용한다면 경기력 향상에 긍정적인 영향을 미칠 것으로 사료된다.

• 한국운동역학회지
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• 제17권3호
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• pp.31-39
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• 2007

The purpose of this study was to observe the kinematic pattern of elite women 100m hurdler race from start to finish and analyze how the change of horizontal velocity makes an influence on the athletes' performance. The analysis was based on the performance of Korean elite 100m hurdler A and international elite hurdlers B and C. Following results were drawn from the analyzation of elite 100m hurdlers' technical characteristics; During the race, hurdler A made more than 8 m/s of horizontal velocity at the 3rd, 4th, 6th, and the 7th hurdle. The horizontal velocity peaked at the 4th hurdle with 8.23 m/s. On the other hand, hurdler B and hurdler C maintained more than 8 m/s of horizontal velocity from the 2nd hurdle through the 10th hurdle. Hurdler B's fastest horizontal velocity was 8.67 m/s from the 6th to the 7th hurdle and hurdler C's fastest horizontal velocity was 8.85 m/s from the 5th to the 8th hurdle. From the start line to the 3rd hurdle, the times achieved by hurdlers A, B, and C were 4.90 sec, 4.65 sec, and 4.52 sec. In the middle of the race, which is from the 4th hurdle to the 7th hurdle, hurdlers A, B, and C ran in 9.10 sec, 8.60 sec, and 8.38 sec. And the latter part of the race to the 10th hurdle, the times hurdlers A, B, and C hit were 12.32 sec, 11.66 sec, and 11.32 sec. To the finish line, it took 1.15 sec for hurdler A, 1.1 sec for B, and 1.06 sec for C. Hence, to set the record of sub-13 sec, hurdler A should improve her acceleration from the start line to the 1st hurdle with the speed more than 5.4 m/s and should maintain more than 8 m/s of horizontal velocity from the 2nd hurdle through the 10th hurdle. In addition, hurdler A should improve her speed endurance to minimize the deceleration of horizontal velocity from the 4th hurdle to the final hurdle. If hurdler A could shorten 0.05 sec of time in each hurdle section, she would be able to set the record under 13 seconds.

• 한국화재소방학회논문지
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• 제26권5호
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• pp.48-53
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• 2012

최소자연발화온도는 가연성액체의 안전한 취급을 위해서 중요한 지표가 된다. 본 연구에서는 ASTM E659 장치를 이용하여 가연성 혼합물인 n-Butanol+sec-Butanol 계의 최소자연발화온도와 발화지연시간을 측정하였다. 2성분계를 구성하는 순수물질인 n-Butanol과 sec-Butanol의 최소자연발화온도는 각 각 $340^{\circ}C$, $447^{\circ}C$로 측정되었다. 그리고 측정된 n-Butanol+sec-Butanol 계의 최소자연발화온도는 제시된 식에 의한 예측값과 적은 평균절대오차에서 일치하였다.

• 열처리공학회지
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• 제11권3호
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• pp.159-167
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• 1998

In this study, friction-wear test was carried out on the carburized layer depth of a mechanical structure steel SNCM carburized with RX and LPG for 7hrs at $930^{\circ}C$ and also the wear properties of wear loss, wear rate, coefficient of friction, friction force and friction temperature were investigated. The wear properties for carburized layer of SNCM were tested on dry condition at the room temperature by the thrust load of 49~245N range at sliding speed of 0.2m/sec and the sliding speed of 0.2~1.0m/sec range at thrust load of 98N. Wear loss on the depth of carburizing layer was increased with increasing of thrust load and sliding speed, and with decreasing of hardness. The condition of worn surfaces were showed mild wear at less than the thrust load of 98N and sliding speed of 0.6m/sec but were showed severe wear at more than 98N and 0.6m/sec. The friction load and temperature were increased with increasing of thrust load but with increasing sliding speed was appeared minimum at 0.6m/sec. With increasing thrust load the wear rate was increased and the coefficient of friction was decreased, but with increasing sliding speed the wear rate and the coefficient of friction were decreased in 0.2~0.6m/sec and increased in 0.6~1.0m/sec, therefore 0.6m/sec in this testing is a transition velocity.

• 한국가축번식학회지
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• 제14권2호
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• pp.133-140
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• 1990

This study was conducted to develop a simple and efficient technique for fusing 2-cell mouse embryos to obtain tertraploid embryos. Various concentration of PEG and exposure times were compared in order to determine the best condition for fusion and subsequent of fused embryos. The results obtained were follows ; 1. The incidence of fusion induction treated with 40% PEG(70.8%) and 45%(62.7%) for 60 sec. exposure were higher than those of 40% and 45% PEG for 30 sec., 90 sec., or 120 sec. exposure group. Also, the highest incidence of fusion induction(76.9%) was achieved with 120 sec. exposure at 50% PEG concentration. 2. Fused embryos after PEG treatment were cleavaged 2-to 4-cell, 8-cell, morula and blastocyst at 20-24 hr., 30-34., 44-52 hr., respectively, and were not different from those obtained fleshly. 3. The high proportions of the embryos developed to blastocysts after blastomere fusion with 40% PEG for 60 sec., 45% PEG for 60 sec. and 50% for 120 sec. were 66.7%(42/63), 69.0%(29/42) and 32.0%(16/50), respectively, this trend indicated that the fusion rate was similar to the incidence of fused embryos forming blastocysts. 4. The cell number of blastocyst developed from fused embryos(18.7 2.6) was samller than that of untreated embryos(48.9 1.69)

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2010년도 제34회 춘계학술대회논문집
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• pp.66-70
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• 2010

우주발사체용 75톤급 액체로켓엔진 연소기의 저압연소시험에서 얻은 데이터를 기본으로 75톤급 연소기의 연소특성속도 및 비추력을 예측하였다. 75톤급 연소기 저압연소시험에서 연소특성속도는 약 1750 m/sec, 비추력은 240 sec로 30톤급 연소기의 저압 성능보다 높은 값을 보여주었다. 30톤급 연소기의 연소시험에서 얻은 저압/고압 관계식을 통해 75톤급 연소기의 설계점에서 연소특성속도는 약 1770 m/sec, 비추력은 약 278 sec로 목표치를 상회하는 값을 예측하였다.

• Journal of Chest Surgery
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• 제30권9호
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• pp.914-919
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• 1997

1990년부터 1995년까지 신촌 세브란스 병원에서 만성 농흉으로 늑막박피술을 시행받은 환자중 수술전 후에 폐기능 검사를 시행한 33례와 폐관류스캔을 동시에 시행한 11례를 대상으로 분석하였다. 1. 수술후 FEV1은 술전 2.30 L/sec에서 2.65 L/sec로 유의하게 증가하였다(p=0.008). 2. 연령별 수술전 후 FEV1의 변화는 20세 미만에서만 통계적으로 유의하게 증가하였으며(p-0.001), 그 이상의 연령군에선 유의성이 얼었다. 3. 만성 농흉의 원인을 결핵성과 비결핵성으로 나누어 수술 전후의 FEV1을 비교시 결핵성 농흉 에서 통계적 으로 유의하게 증가하였(p=0.008). 4. 추적관찰 기간에 따른 FEVI의 변화는 24개월 이전에선 유의한 변화가 없었으나 24개월 이후에서 통계적 으로 유의하게 증가하였다0=0.013). 5. 늑막박피술을 시행받은 폐의 관류량은 술전 21.5.%에서 술후 26.9%(p=0.046), FEVI은 술전 0.56 L/sec에서 술후 0.78 L/sec(p=0.071) 증가하였으며, 반대측 폐의 관류량은 술전 78.4%에서 술후 72.9%(p=0.042), FEVi 은 술전 2.04 L/sec에서 수술후 2.03 L/sec로 감소하였다.

• BMB Reports
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• 제44권11호
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• pp.719-724
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• 2011

The $Sec61{\alpha}$ subunit is the core subunit of the protein conducting channel which is required for protein translocation in eukaryotes and prokaryotes. In this study, we cloned a $Sec61{\alpha}$ subunit from Penicillium ochrochloron ($PoSec61{\alpha}$). Sequence and 3D structural model analysis showed that $PoSec61{\alpha}$ conserved the typical characteristics of eukaryotic and prokaryotic $Sec61{\alpha}$ subunit homologues. The pore ring known as the constriction point of the channel is formed by seven hydrophobic amino acids. Two methionine residues from transmembrane ${\alpha}$-helice 7 (TM7) contribute to the pore ring formation and projected notably to the pore area and narrowed the pore compared with the superposed residues at the corresponding positions in the crystal structures or the 3D models of the $Sec61{\alpha}$ subunit homologues in archaea or other eukaryotes, respectively. Results reported herein indicate that the pore ring residues differ among $Sec61{\alpha}$ subunit homologues and two hydrophobic residues in the TM7 contribute to the pore ring formation.

• Korea-Australia Rheology Journal
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• 제17권3호
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• pp.125-130
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• 2005

Coalescence process of binary immiscible fluid mixtures having bimodal size distributions, prepared by mixing two pre-sheared samples at different shear rates, ${\gamma}_{pre1}\;and\;{\gamma}_{pre2}$, under shear flow at a final shear rate, ${\gamma}_f$, are examined by transient shear stress measurements and microscopic observations in comparison with the results for simply pre-sheared samples having narrow size distributions (unimodal distribution samples). Component fluids are a silicone oil (PDMS) and a hydrocarbon-formaldehyde resin (Genelite) and their viscosities are 14.1 and 21.0 $pa{\cdot}sec$ at room temperature $(ca.\;20^{\circ}C)$, respectively. The weight ratio of PDMS: Genelite was 7:3. Three cases, $({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;({\gamma}_{pre1}=0.8sec^{-1},\;{\gamma}_{pre2}=4.0sec^{-1}\;and\;{\gamma}_f=2.4sec^{-1}),\;and\;({\gamma}_{pre1}=7.2sec^{-1},\;{\gamma}_{pre2}=12.0^sec^{-1}\;and\;{\gamma}_f=7.2sec^{-1})$ the first case, transient shear stress did not show any significant difference but domains larger than the initial state are observed at short times. In the latter cases, there exist undershoot of shear stress, reflecting existence of deformed large domains, which is confirmed by the direct observation. It is concluded that coalescence between large and small domains more frequently occur than coalescence between the domains with similar size in the bimodal distribution samples.