• 한국정보처리학회:학술대회논문집
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• 한국정보처리학회 2022년도 춘계학술발표대회
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• pp.31-31
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• 2022

• 한국레이저가공학회지
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• 제9권1호
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• pp.25-29
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• 2006

This study aimed to investigate the change of mechanical properties with the rolling direction and shielding condition during laser welding of AZ31 magnesium alloy. AZ31 magnesium alloy sheets of 1mm thickness were welded using a continuous wave Nd:YAG laser with and without Ar shielding gas. The effect of Ar shielding gas and rolling direction on the mechanical properties were investigated using Vickers hardness, transverse-weld tensile. Porosity in the weld metals was investigated using an optical microscope. The experimental results showed that mechanical properties of AZ31 magnesium alloy laser welds were upgraded compared to those of base metal. Mechanical properties of AZ31 magnesium alloy laser welds were not substantially changed when Ar shielding gas was supplied.

• Korean Journal of Mathematics
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• 제31권3호
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• pp.349-361
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• 2023

In this article, we construct lacunary ∆^m-statistical convergence for triple sequences within the context of intuitionistic fuzzy n-normed spaces (IFnNS). For lacunary ∆^m-statistical convergence of triple sequence in IFnNS, we demonstrate numerous results. For this innovative notion of convergence, we further built lacunary ∆^m-statistical Cauchy sequences and offered the Cauchy convergence criterion.

• 미생물학회지
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• 제53권4호
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• pp.273-285
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• 2017

본 연구에서는 프로바이오틱 유산균이 생산한 항균물질에 의한 바이오제닉 아민 생성균의 제어 효과와 박테리오신 및 유기산의 항균 활성에 영향을 미치는 배양 조건을 조사하였다. Lactobacillus plantarum FIL20 (64 AU/ml) 및 Lactobacillus paracasei FIL31 (128 AU/ml)의 박테리오신 용액은 Serratia marcescens CIH09과 Aeromonas hydrophilia RIH28에 각각 강한 항균 활성을 나타내었고 FIL20과 FIL31 균주로부터 얻은 배양 상등액 내에 유산 함유량은 각각 $107.3{\pm}2.7mM$과 $129.5{\pm}4.6mM$로 나타났다. 따라서 L. plantarum FIL20과 L. paracasei FIL31이 생산한 박테리오신 용액(200 AU/ml) 및 배양 상등액($200{\mu}l/ml$)의 처리에 의해 S. marcescens CIH09 및 A. hydrophilia RIH28의 균수 및 히스타민과 티라민의 생성량을 유의하게 감소시켰다(P < 0.05). 초기 pH (5.0)와 배양 온도($15^{\circ}C$)가 낮은 조건 하에서 CIH09 균주가 생산한 히스타민과 티라민의 생성량은 L. plantarum FIL20이 생산한 박테리오신 용액이나 배양 상등액 처리에 의해 유의하게 감소되었다. 또한 식염 5% 혹은 아질산 칼륨($200{\mu}g/g$)과 FIL20 유산균의 항균물질을 혼용한 경우 바이오제닉 아민을 생성하는 세균의 균수와 유해 아민 함량을 유의하게 감소시켰다(P < 0.05). 결론적으로 L. plantarum FIL20과 L. paracasei FIL31의 박테리오신 및 유기산 용액은 허들 테크놀로지에 적용하여 바이오제닉 아민 생성을 효과적으로 제어할 수 있는 생물학적 보존제로 이용될 수 있을 것이다.

• 한국광학회지
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• 제18권5호
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• pp.333-336
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• 2007

[ $-40^{\circ}C$ ]에서 $85^{\circ}C$의 온도에서 냉각장치 없이 동작하는 1.31 um 비냉각 DFB-LD가 유기 금속 화학 증착법에 의해 성장되었다. 높은 전광변환효율을 갖는 레이저의 제작은 스트레인이 인가된 다중양자우물 구조의 최적화를 통해 가능하며, 특히 스트레인의 양, 양자 우물의 두께, 전위장벽의 두께, 양자 우물의 수, 활성층의 폭에 주로 영향을 받는다. 본 연구에서 제작된 DFB-LD는 $25^{\circ}C$와 $85^{\circ}C$에서 전광변환효율은 0.38[mW/mA]와 0.26[mW/mA], 발진개시전류는 각각 7.1[mA]와 19.8[mA]의 값을 가졌다.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2009년도 추계학술대회 논문집
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• pp.285-288
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• 2009

The purpose of this study is to predict the forming limit diagram (FLD) of strain-rate sensitive materials on the basis of the Marciniak and Kuczynski (M-K) theory. The strain-rate effect is taken into consideration in such a way that the stress-strain curves for various strain-rates are inputted into the formulation as point data, not as curve-fitted models such as power function. Tensile tests and R-value tests were carried out at several levels of temperature and strain-rate from $25^{\circ}C$ to $300^{\circ}C$ and 0.16 to 0.00016/s, respectively to obtain the mechanical properties of AZ31B magnesium alloy sheet. The FLD of this material was experimentally obtained by limit dome height tests with the punch velocity of 0.1 and 1.0 mm/s at $250^{\circ}C$. The M-K theory-based FLD predicted using Yld2000-2d yield criterion was compared with the experimental results.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 춘계학술대회
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• pp.1326-1331
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• 2003

Thick PZT films are required for the cases of micro actuators and sensors with high driving force, high breakdown voltage and high sensitivity, and so on. In this work, thick PZT films were fabricated by Sol-Gel multi-coating method. Total 8 types of samples using thick PZT films with thicknesses, about $1{\mu}m$ and $2{\mu}m$, and Pt top electrodes shapes for measuring transverse piezoelectric coefficient ($e_{31,f}$) were fabricated using MEMS processes. They were characterized by fabricated e31,f measurement system before and after poling. $e_{31,f}$ values of samples after poling were higher than before poling. Those of $2{\mu}m$ thick PZT films were also higher than $1{\mu}m$ thick PZT films. And those with long electrodes as top electrodes were also higher than shorter.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2016년도 추계학술대회 논문집
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• pp.124.2-124.2
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• 2016

Corrosion resistance and adhesion of electro-paint (E-paint) with fluoride conversion coating (FCC) on AZ31 Mg alloy were studied. Corrosion resistance and adhesion were studied as a function of FCC-treatment time and concentration of FCC-bath. Aqueous hydrogen fluoride (HF) solutions, with concentrations ranging from 0.5 M to 5 M, were used to form FCC on chemically polished AZ31 Mg alloy samples for six different times; 10, 30, 60, 90, 120, and 180s. The results from salt spray test (SST) showed that corrosion resistance of E-paint appeared to decrease with increasing FCC treatment times in low concentration FCC baths. The number of blisters formed on the FCC-treated samples increased with increasing FCC treatment time of more than 1 min in low concentration (0.5 M to 1 M) solutions. On the other hand, samples treated in the 5 M HF solution for 120s showed no delamination or blistering even after 1200h of SST.

• 한국해양학회지:바다
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• 제8권3호
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• pp.237-242
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• 2003

실험실에서 황복을 부화 후 1일에서 63일까지 사육하면서 표본을 추출하여 황복의 초기성장과 이석의 미세구조 관찰하였다. 부화 당시 황복의 전장은 3.09$\pm$0.02 mm였으며, 부화 후 10일에 전장 4.96$\pm$0.24 mm, 20일에는 5.39$\pm$0.42 mm, 30일에는 9.13$\pm$0.59 mm로 성장하였고, 부화 후 34일에는 평균 10.78$\pm$0.96 mm로 성장하였으며, 부화 후 43일에는 16.40$\pm$2.31 mm, 부화 후 63일에는 30.49$\pm$1.53 mm로 성장하였다. 부화한 황복 이석의 평균 장반경은 14.20$\pm$1.21 $\mu\textrm{m}$였고, 부화 후 10일째는 31.06$\pm$2.31 $\mu\textrm{m}$, 20일째는 57.19$\pm$6.19 $\mu\textrm{m}$, 34일째는 127.13$\pm$13.13 $\mu\textrm{m}$, 43일째는 190.79$\pm$17.08 $\mu\textrm{m}$, 63일째는 281.85$\pm$23.81 $\mu\textrm{m}$로 부화 후 20일 이후의 이석의 크기변화는 체장의 성장 경향과 유사하였다 황복의 이석에는 다른 성장선들과 구별되는 부화정지선이 형성되어있으며, 부화정지선 형성이전에 2-3개의 미세성장선이 관찰되었다. 부화 후 20일부터 63일까지, 황복의 이석에 형성된 일일성장선의 수와 경과한 일수는 1차 비례관계를 보였으며, 하루에 한 개씩 형성되어지는 것이 확인되었다.

• 대한물리치료과학회지
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• 제9권2호
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• pp.67-75
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• 2002

The purpose of this study is to know the average of hip joint range of motion and difference according to the aging for the elderly. This study consisted of elder male(n=75) and elder female(n=109). The result of assessment and analysis in hip pint range of motion are as follows : 1) The average hip flexion(knee flexed) joint range of motion in 60-69(from sixty to sixty-nine)years old are $104.26^{\circ}$(Left-Male), $101.00^{\circ}$(Right-Male), $107.05^{\circ}$(Left-Female), $107.05^{\circ}$(Right-Female). 70-79years old are $104.59^{\circ}$(L-M), $102.05^{\circ}$(R-M), $105.73^{\circ}$(L-F), $108.75^{\circ}$(R-F). 80-89years old are $101.53^{\circ}$(L-M), $101.13^{\circ}$(R-M), $96.83^{\circ}$(L-F), $97.67^{\circ}$(R-F). There was significant difference in hip flexion(knee flexed) among female group(p<.01). The average hip flexion(knee extended) joint range of motion in 60-69(from sixty to sixty-nine)years old are $73.13^{\circ}$(Left-Male), $72.04^{\circ}$(Right-Male), $77.29^{\circ}$(Left-Female), $75.97^{\circ}$(Right-Female). 70-79years old are $74.95^{\circ}$(L-M), $72.19^{\circ}$(R-M), $76.73^{\circ}$(L-F), $76.65^{\circ}$(R-F). 80-89years old are $70.83^{\circ}$(L-M), $70.37^{\circ}$(R-M), $69.00^{\circ}$(L-F), $69.00^{\circ}$(R-F). There was significant difference in left hip flexion(knee extended) among female group(p<.05). 2) The average hip extension joint range of motion in 60-69years old are $13.09^{\circ}$(L-M), $12.78^{\circ}$(R-M), $10.97^{\circ}$(L-F), $10.68^{\circ}$(R-F). 70-79years old are $8.95^{\circ}$(L-M), $8.48^{\circ}$(R-M), $11.24^{\circ}$(L-F), $10.90^{\circ}$(R-F). 80-89 years old are $8.40^{\circ}$(L-M), $8.23^{\circ}$(R-M), $7.33^{\circ}$(L-F), $7.33^{\circ}$(R-F). There was significant difference in left(p<.01) and right(p<.05) hip extension among male group(p<.05). 3) The average hip abduction joint range of motion in 60-69 years old are $33.04^{\circ}$(L-M), $33.17^{\circ}$(R-M), $33.16^{\circ}$(L-F), $33.37^{\circ}$(R-F). 70-79 years old are $31.00^{\circ}$(L-M), $30.05^{\circ}$(R-M), $32.44^{\circ}$(L-F), $32.68^{\circ}$(R-F). 80-89 years old are $29.07^{\circ}$(L-M), $27.90^{\circ}$(R-M), $28.17^{\circ}$(L-F), $28.67^{\circ}$(R-F). There was no significant difference among group. 4) The average hip adduction pint range, of motion in 60-69years old are $29.57^{\circ}$(L-M), $29.35^{\circ}$(R-M), $31.87^{\circ}$(L-F), $31.89^{\circ}$(R-F). 70-79, years old are $27.41^{\circ}$(L-M), 27.00(R-M) $30.85^{\circ}$(L-F), $31.28^{\circ}$(R-F). 80-89 years old are $26.87^{\circ}$(L-M), $26.63^{\circ}$(R-M), $24.67^{\circ}$(L-F), $24.83^{\circ}$(R-F). There was significant difference in hip abduction among female group(p<01). 5) The average hip external rotation pint range of motion in 60-69years old are $32.26^{\circ}$(L-M), $31.17^{\circ}$(R-M), $33.53^{\circ}$(L-F), $34.42^{\circ}$(R-F). 70-79 years old are $31.64^{\circ}$(L-M), $28.62^{\circ}$(R-M) $31.29^{\circ}$(L-F), $31.45^{\circ}$(R-F). 80-89 years old are $26.40^{\circ}$(L-M), $26.07^{\circ}$(R-M), $24.77^{\circ}$(L-F), $24.27^{\circ}$(R-F). There was significant difference in left(male, female p<.01) and right(female p<.0l) hip external rotation among group. 6) The average hip internal rotation joint range of motion in 60-69years old are $30.30^{\circ}$(L-M), $28.13^{\circ}$(R-M), $34.27^{\circ}$(L-F), $36.03^{\circ}$(R-F). 70-79years old are $31.24^{\circ}$(L-M), $29.57^{\circ}$(R-M), $28.51^{\circ}$(L-F), $29.10^{\circ}$(R-F). 80-89 years old are $24.63^{\circ}$(L-M), $24.40^{\circ}$(R-M), $24.27^{\circ}$(L-F), $24.27^{\circ}$(R-F). There was significant difference in left(male p<.05, female p<.01) and right(female p<.01) hip internal rotation among group.