• 한국정보전자통신기술학회논문지
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• 제16권2호
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• pp.109-115
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• 2023

본 논문은 UV(ultraviolet) 처리된 자기 조립 단분자막(fluorinated self-assembled monolayers; FSAM)을 배향막으로 사용한 액정의 배향 특성을 분석하였다. 물리화학적 분석을 사용하여 UV 처리 전후의 ITO(indium-tin-oxide) 유리 기판의 FSAM 특성을 확인하였다. FSAM 표면은 UV 처리에 의해 소수성에서 친수성으로 변화하였다. LC(liquid crystal) 분자는 UV 처리된 FSAM 표면에서 수평방향으로 정렬되었고 선경사각도 90°에서 0°로 변화하였다. UV 처리된 FSAM을 배향막으로 사용하여 제작된 TN(twist nematic) 셀의 전기광학(electro optics; EO) 특성은 기존의 PI(polyimide) 배향막에 비해 응답 시간이 빠른 것을 확인하였다. 이는 UV 처리된 FSAM 이 LCD(liquid crystal display)의 기존 폴리이미드 배향막을 대체할 잠재적인 가능성을 가진다.

• 대한간호학회지
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• 제33권8호
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• pp.1153-1160
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• 2003

Purpose. 1) To identify the time taken from symptom onset to the arrival at the hospital (pre-hospital delay time) and time taken from the arrival at the hospital to the initiation of the major treatment (in-hospital delay time) 2) to examine whether rapid treatment results in lower mortality. 3) to examine whether the pre- and in-hospital delay time can independently predict in-hospital mortality. Methods. A retrospective study with 586 consecutive AMI patients was conducted. Results. Pre-hospital delay time was 5.25 (SD=10.36), and in-hospital delay time was 1.10 (SD=1.00) hours for the thrombolytic therapy and 50.24 (SD=121.18) hours for the percutaneous transluminal coronary angio-plasty (PTCA). In-hospital mortality was the highest when the patients were treated between 4 to 48 hours after symptom onset using PTCA (p=.02), and when treated between 30 minutes and one hour after hospital arrival using thrombolytics (p=.01). Using a hierarchical logistic regression model, the pre- and in-hospital delay times did not predict the in-hospital mortality. Conclusion. Pre- and in-hospital delay times need to be decreased to meet the desirable therapeutic time window. Thrombolytics should be given within 30 minutes after arrival at the hospital, and PTCA should be initiated within 4 hours after symptom onset to minimize in-hospital mortality of AMI patients.

• Food Science and Biotechnology
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• 제18권2호
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• pp.374-378
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• 2009

Three physical methods, photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance (ESR), have been applied to detect the irradiation treatment for the non- and steamed sesame seed samples. PSL successfully screened the irradiated samples from the non-irradiated control by comparing their photon counts (PCs) with the lower (less than 700 count/60 sec) and upper threshold values (higher than 5,000 count/60 sec). TL signals were still detected in all irradiated samples even after steaming, which was reconfirmed with TL ratios [integrated area of $TL_1$ (the first glow)/$TL_2$ (the second glow)] through re-irradiation step. ESR spectrometry showed that radiation-induced cellulose radicals were detected in all the irradiated samples irrespective of steaming treatment. Identification of the irradiated sesame seeds was possible even after steaming by analyzing PSL, TL, and ESR.

• 한국식품저장유통학회지
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• 제13권2호
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• pp.223-227
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• 2006

Anti-H pylori 항체를 함유한 면역우유를 $60^{\circ}C$에서 30분 열처리한 것과 열처리하지 않은 Anti-H. pylori 항체를 함유한 원유의 면역활성 비교시 99.99(100)%의 면역 활성을 나타내었으며, $75^{\circ}C$ 이상의 열처리에 의해서는 면역 활성이 급격하게 감소하여 약 50%이하로 감소하였다. 열처리 온도가 높을수록, 열처리 시간이 증가할수록 총균수의 감소율이 증가하였다. Coliform bacteria의 경우는 원유에서 $10^2\;CFU/mL$이 관찰되었으나 모든 열처리 구에서는 관찰되지 않았다. 면역우유를 $2^{\circ}C,\;4^{\circ}C$ 그리고 $10^{\circ}C$에서 21일 동안 저장한 결과 면역우유의 저장 중pH의 변화는 저장 21일 동안 $2^{\circ}C$와 $4^{\circ}C$에 저장한 경우 저장온도에 따른 뚜렷한 변화는 관찰할 수 없었으며, $10^{\circ}C$에 저장한 경우 저장 7일 이후 급격히 감소하였다. 총균수의 변화는 저장 초기 $10^3\;CFU/mL$에서 $2^{\circ}C$와 $4^{\circ}C$에 저장한 열처리 면역우유의 총균수는 저장 21일 동안 뚜렷한 증가현상을 관찰할 수 없었으며, $10^{\circ}C$에 저장하였을 경우 7일 이후 급격히 증가하여 저장 14일째 $10^8\;CFU/mL$로 부패현상을 나타내었다. 면역우유의 저장 중 면역 활성의 변화는 저장 온도에 관계없이 저장 14일까지는 저장초기의 활성에 비해 뚜렷한 차이는 나타나지 않았으나 14일 이후 급격히 감소하는 경향을 나타내었다.

• 열처리공학회지
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• 제32권6호
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• pp.256-262
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• 2019

The microstructural features and texture development by both hot rolling and hot forging in ${\gamma}-TiAl$ alloy were investigated. In addition, additional heat treatment after hot forging was conducted to recognize change of the microstructure and texture evolution. The obtained microstructural features through dynamic recrystallization after hot deformed ${\gamma}-TiAl$ were quite different because two kinds of formation process were occurred depending on deformation condition. However, analyzed texture tends to be random orientation due to intermediate annealing up to ${\alpha}+{\beta}$ region during the hot deformation process. After additional heat treatment, microstructure transformed into fully lamellar microstructure and randomly oriented texture was also observed due to the same reason as before. Tensile test at room temperature demonstrated that anisotropy of mechanical properties were not appeared and transgranular fracture was occurred between interface of ${\alpha}_2/{\gamma}$. As a result, it could be suggested that microstructural features influenced much more than texture development on mechanical properties at room temperature.

• 한국환경복원기술학회지
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• 제10권1호
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• pp.9-15
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• 2007

The study was conducted to find out the harvesting time, storage duration, cold treatment and sterilization on seed germination of Miscanthus sinensis. The optimum harvesting time of the Miscanthus seed in native to Jeju island was December. And the seed germination passible 3 years after harvesting. When the seeds had cold treatment, seed germination nate was 74% rather than 63% of non-treatment. For seed sterilization treatment, soaking in solution of Benomyl 7% during from 3 hours to 12 hours germinated 9% over. But the non-treatment on 24 hours treatment reduced the seed germination of Miscanthus sinensis.

• Journal of Welding and Joining
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• 제31권3호
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• pp.66-75
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• 2013

In this study, the effect of coating thickness($20{\mu}m$ and $30{\mu}m$) on microstructure and tensile properties in Yb:YAG disk laser welds of Al-Si-coated boron steel (1.2mmt) was investigated. In the case of as welds, the quantity of ferrite was found to be higher in base metal than that in HAZ (Heat Affected Zone) and fusion zone, indicating, fracture occurrs in base metal, and the fracture position is unrelated to the coating thickness. Furthermore, yield strength, tensile strength of base metal and welded specimens showed similar behavior whereas elongation was decreased. On the other hand, base metal and HAZ showed existence of martensite after heat treatment, the fusion zone indicated the presence of full ferrite or austenite and ferrite during heat treatment ($900^{\circ}C$, 5min), After water cooling, austenite was transformed to martensite, and the quantity of ferrite in fusion zone was higher as compared with in base metal, resulting in sharply decrease of yield strength, tensile strength and elongation, which leads to fracture occured at fusion zone. In particular, results showed that because the concentration of Al was higher in 30um coating layer specimen than that of 20um coating specimen, after heat treatment, producing a higher quantity of ferrite was higher after heat treatment in the fusion zone; howevers, it leads to a lower tensile property.

• 열처리공학회지
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• 제28권3호
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• pp.126-133
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• 2015

The aim of this study is to investigate the effect of solution treatment on the corrosion behavior of Mg-8%Al-(0-1)%Zn casting alloys in 1M NaCl aqueous solution. After the solution treatment, all alloys showed single ${\alpha}$-(Mg) phase microstructure by dissolution of ${\beta}(Mg_{17}Al_{12})$ phase into the ${\alpha}$-(Mg) matrix. The $H_2$ evolution volume decreased with an increase in Zn content, which indicates that the addition of Zn plays a beneficial role in decreasing corrosion rate of the Mg-Al-Zn alloy in solution-treated state. The microstructural evaluations on the corrosion products and corroded surfaces after the immersion test in 1 M NaCl solution revealed that the incorporation of more $Al_2O_3$ and ZnO into the corrosion product, by which the penetration of $Cl^-$ ions is impeded, are thought to be responsible for the better corrosion resistance in relation with the Zn addition.

• Journal of the Korean Wood Science and Technology
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• 제20권3호
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• pp.11-20
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• 1992

Steam explosion is one of the most effective pretreatment for fractionating wood. This leads to the total utilization of wood basic components; cellulose, hemicellulose and lignin. The amount of sugar and lignin extracted with the hot water method was very low. The lignin content of residues after extraction with using a sodium hydroxide treatment, increased delignification of carbohydrate as the concentration of alkali was increased. Oak, pretreated with steam exploded at 25kg/$cm^2$ for 6 min. then 1% alkali for 2hrs. showed a delignification rate up to 95%. A sodium chlorite treatment of steam exploded pine and oak also afforded a high deligninfication effect. Pine, treated 10% sodium chlorite for 2hrs. showed high delignification. However, by using a sodium hydroxide treatment, a 2% retreatment for Ihr. after a 2% for 2hrs. afforded remarkable delignification effect on exploded wood at 30kg/$cm^2$ for 9min. and at 35kg/$cm^2$ for 3-6min. In oak, an initial 2hrs. treatment of 2% sodium chlorite was followed by a second 2hrs. treatment at 10%. This showed a delignification rate of 96%.

• Journal of the Korean Wood Science and Technology
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• 제39권2호
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• pp.172-178
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• 2011

Three different finger-jointed lumbers which have different geometric features and adhesives were manufactured and studied in this study. Larch and pitch pine lumbers with and without preservative treatment were used. Bending MOE was measured as the preliminary investigation for grouping the specimen. After the finger, bending MOE of two wood species without preservative treatment shows over 97% property of the control group. The tensile modulus also shows almost same property after the finger joint. And it is found out that the preservative treatment induce little effect on bending and tensile MOE. Based on this result, high performance of examined finger-jointed lumber can be found out. However, tensile strength decreased around 20% which would be induced by the crack along the root of the finger which is formed near the edge during manufacturing stage. And finger-jointed lumber with preservative treatment even shows higher decrement of the tensile strength with higher wooden part failure mode.