• 대한의용생체공학회:학술대회논문집
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• 대한의용생체공학회 1998년도 추계학술대회
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• pp.177-178
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• 1998

This paper is a study on compensation for error in estimation of mean pressure according to the change of arterial pressure shape. Because arterial pressure shape affects the mean pressure and blood volume which are important factors for measurement of blood pressure(BP), change of arterial pressure shape cause BP measurement error. In order to solve this problem, we add the compensation function C($\alpha$), depending on arterial pressure shape, to mathematical oscillometric model. Consequently, we could accurately estimate the blood pressure by correcting of the error using compensation function.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.668-673
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• 2000

Spud angle( ${\alpha}$ ) and fuel injection angle ( ${\beta}$ ) have strong influence on spud type gas burner combustion. A wide range of flame stability is shown at ${\alpha}=60^{\circ}$, but at ${\alpha}=30^{\circ}$ is narrow. Optimum condition of flame stability swirl angle( ${\gamma}$ ) is $40^{\circ}$. At condition of ${\alpha}=30^{\circ}$ flame shape is relatively narrow and long, on the other hand, at ${\alpha}=60^{\circ}$ flame is wide and short. Regardless of spud angle, maximum flame temperature shows in the range of Z=200mm and R=0mm. Flame temperature, on the whole, is high at ${\alpha}=45^{\circ}$. At ${\alpha}=45^{\circ}$, NOx emission is higher than other conditions that may be concerned with flame temperature. At ${\beta}=60^{\circ}$ and ${\gamma}=40^{\circ}$, NOx emission is reduced due to fuel injection angle.

• 한국식품영양학회지
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• 제11권5호
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• pp.565-569
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• 1998

The strain BY-445 which produces new inhihitors of ${\alpha}$-amylase was isolated from a soil sample and identified. The aerial hyphae of this strain develope in the from of open spirals. The spore chain of BY-445 strain appears in spiral shape with spiny surface. Melanoid and soulble pigments were not observed. Gelatin was liquefied, and skin milk and starch was also hydrolyzed. The isolate contained LL-diaminopimelic acid in its cell wall hydrolysate. The content of fatty acid 16:iso, 15:0 anteiso and 16:0 was 25:30, 16.19 and 13.16%, respectively. BY-445 strain was closely related to Streptomyces violaceusinger but it was different from this strain in some cultural and physiological characteristics. This strain was, therefore, designated as Streptomyces sp. BY 445.

• 한국결정성장학회지
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• 제4권2호
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• pp.190-198
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• 1994

자체 제작한 EFG 장치를 이용하여 ${alpha}-Al_2O_3$ rod 형태의 단결정을 육성하였다. EFG법의 원리를 연구하여 성장 조건을 수립하였고 성장한 단결정의 결함 voids, striation, 균열, 과 냉각 현상을 광학현미경으로 분석하였다.

• 한국의류학회지
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• 제24권7호
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• pp.1015-1024
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• 2000

The purpose of this study is 1) to analyse the bending property of the fused fabric and each component of the fused fabrics. 2) to examine the effect of fusing temperature on the bending property of the fused interlining and fused fabrics. 3) to examine the changes of B/W, 2HB/W and TAV of the fused fabrics according to the types of face fabric, interlining, fusing temperature. Five types of wool fabric, four types of shingosen fabric and four types of interlining were used for this study. The fusing condition in this study were the three types of fusing temperature of 10$0^{\circ}C$, 12$0^{\circ}C$, 14$0^{\circ}C$, the pressure of 4 kgㆍf/$cm^2$, and pressing time of 12 seconds. The results obtained from this study were as follows. 1) The bending rigidities and hysteresis of fabrics after fusing were increased. The bending behavior of fused fabrics were governed by the bending behavior of face fabric and interlinings and $\alpha$$_{B}$ values. 2) The KES standardized basic values of B/W and 2HB/W were increased after fusing. The B/Ws of fused fabrics were mainly determined by the $\alpha$$_{B}$ values of interlinings. The 2HB/Ws of fused fabrics seemed to be controlled by the fusing temperature. 3) The changes of TAVs of wool fused fabrics differed from those of shingosen fused fabrics. As the $\alpha$$_{B}$ values of fabric were larger and fusing temperature were increased, the TAVs of wool fused fabrics were smaller though those of shingosen fused fabrics were larger. 4) The TAVs of fused fabrics were highly correlated with the B/Ws of fused fabrics. In the case of wool fused fabrics, the TAVs of fused fabrics were negativly correlated with the 2HB/Ws of wool fabrics and used interlinings.nings.

• 방사성폐기물학회지
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• 제6권2호
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• pp.111-117
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• 2008

배관 내부의 방사성 오염도를 측정하기 위한 ZnS(Ag)/플라스틱섬광체 조합의 알파/베타선 동시측정용 phoswich 검출기를 개발하였다. 알파/베타선 동시측정용 phoswich 검출기의 오염위치에 따른 검출 성능을 PSD (Pulse shape discrimination) 방법을 이용하여 평가하였다. 또한, 검출기를 방사성 오염물질로부터 보호하기 위한 오염방지용 필름에 대한 방사선 감쇄 정도를 실험적으로 평가하였다. PSD 방법으로 알파/베타선 분리 정도를 측정한 결과 충분히 알파와 베타선이 분리되었으며 오염방지용 필름의 적용 가능성을 확인하였다.

• 한국섬유공학회:학술대회논문집
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• 한국섬유공학회 2007년도 학술발표회 논문집
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• pp.467-468
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• 2007

• Applied Biological Chemistry
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• 제41권1호
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• pp.18-22
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• 1998

Bacillus licheniformis를 화학적 돌연변이를 시켜 내열성 ${\alpha}-amylase$ 고생산성 변이주 SK-5를 얻었다. 변이주는 모균에 비하여 약 50배 정도의 ${\alpha}-amylase$를 생산하였으며, 그 모양이 가늘고 길이가 길어졌고, 성장속도가 감소되었다. 이 효소의 유전적 변화를 분석하기 위하여 변이주 SK-5로부터 ${\alpha}-amylase$ 유전자 염기배열을 결정한 결과 구조유전자의 염기배열은 동일하였으나 promoter 지역에서 일부 변이가 일어난 것이 확인되어 이것이 부분적으로 효소생산성 증가에 영향을 미칠 것으로 여겨진다. SK-5의 ${\alpha}-amylase$ 생산성이 높기 때문에 이의 배양상층액으로부터 열처리와 황산암모늄 침전 후 한 단계의 hydroxyapatite 컬럼을 사용하여 순수하게 정제된 ${\alpha}-amylase$를 얻을 수 있었다. 변이에 따른 세포외 단백질분해효소의 영향을 검증하기 위하여 SK-5 배양액을 시간별로 준비하여 Western blot으로 분석한 결과 변이주에서 분비되는 ${\alpha}-amylase$의 구조에 변화가 없음을 확인하였다.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2006년도 제32회 KOSCO SYMPOSIUM 논문집
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• pp.96-104
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• 2006

In the present paper, the effects of combustion instability on flow structure and flame dynamic with the configurations of burner exit in a model gas turbine combustor are investigated using large eddy simulation(LES). A G-equation flamelet model is employed to simulate the unsteady flame behavior. As a result of mean flow field, the change of divergent half angle(${\alpha}$) at burner exit results in variations in the size and shape of the central toroidal recirculation(CTRZ) as well as flame length by changing corner recirculation zone(CRZ). The case of ${\alpha}=45^{\circ}$ show smaller size and upstream location of CTRZ than that of $90^{\circ}$ and $30^{\circ}$ by the development of higher swirl velocity. The flame length in the case of ${\alpha}=45^{\circ}$ is the most shortest, while that in the case of ${\alpha}=30^{\circ}$ is the longest by the decrease of effective reactive area with the absence of CRZ. Through the analysis of pressure fluctuation, it is identified that the case of ${\alpha}=45^{\circ}$ shows the most largest damping effect of pressure oscillation in all configurations and brings in the noise reduction of 2.97dB, comparing with that of ${\alpha}=30^{\circ}$ having the largest pressure oscillation. These reasons are discussed in detail through the analysis of unsteady phenomena about recirculation zone and flame surface. Finally the effects of flame-acoustic interaction are evaluated using local Rayleigh parameter.

• 한국주조공학회지
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• 제33권3호
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• pp.103-112
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• 2013

Effect of Fe and Mn contents on the tensile properties of Al-4 wt%Mg-0.9 wt%Si alloy system has been studied. Common phases of Al-4 wt%Mg-0.9 wt%Si alloy system were ${\alpha}$-Al, $Mg_2Si$, ${\alpha}-Al_{12}(Fe,Mn)_3Si$ and ${\beta}-Al_5FeSi$. As Fe content of Al-4 wt%Mg-0.9 wt%Si alloy system increased from 0.15 wt% to above 0.3 wt%, ${\beta}-Al_5FeSi$ compound appeared. When Mn content of the alloy increased from 0.3 wt% to 0.5 wt%, morphology of plate shaped ${\beta}-Al_5FeSi$ compound changed to chinese script ${\alpha}-Al_{12}(Fe,Mn)_3Si$. As Fe content of Al-4 wt%Mg-0.9 wt%Si-0.3 wt%Mn alloy increased from 0.15 wt% to 0.4 wt%, tensile strength of the as-cast alloy decreased from 191 MPa to 183 MPa and, elongation of the alloy also decreased from 8.0% to 6.2%. Decrease of these properties can be explained as the formation of plate shape, ${\beta}-Al_5FeSi$ phase with low Mn/Fe ratio of the alloy. However, when Mn content of Al-4 wt%Mg-0.9 wt%Si-0.3 wt%Fe alloy increased from 0.3 wt% to 0.5 wt%, tensile strength of as-cast alloy increased from 181 MPa to 194 MPa and, elongation of the alloy increased from 6.8% to 7.0%. These improvements attribute to the morphology change from ${\beta}-Al_5FeSi$ phase to chinese script, ${\alpha}-Al_{15}(Fe,Mn)_3Si_2$ phase shape-modified from with high Mn/Fe ratio of the alloy.