• Journal of Ceramic Processing Research
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• 제19권6호
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• pp.450-454
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• 2018

In recent years, thermal insulation coating technology for automotive engine parts has received significant attention as a means of improving the thermal efficiency of automotive engines. One of the characteristics of thermal insulation coatings is their low thermal conductivity, and, materials such as YSZ (Yttria-stabilized zirconia), which have low thermal conductivity, are used for this purpose. This research presents a study of the changes in the microstructure and thermal conductivity of $8YSZ/SiO_2$ multi compositional thermal insulation coating for different compositions, and particle size distributions of suspension, when it is subjected to suspension plasma spraying. To obtain a porous coating structure, the mixing ratio of 8YSZ and $SiO_2$ particles and the particle sizes of the $SiO_2$ were changed. The microstructure, phase formation behavior, porosity and thermal conductivity of the coatings were analyzed. The porosities were found to be 1.2-32.1%, and the thermal conductivities of the coatings were 0.797-0.369 W/mK. The results of the study showed that the microstructures of the coatings were strongly influenced by the particle size distributions, and that the thermal conductivities of the coatings were greatly impacted by the microstructures of the coatings.

• Progress in Superconductivity
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• 제1권1호
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• pp.61-67
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• 1999

We evaluated the effect of alloying element additions to Ag sheath on mechanical, electrical and thermal properties of Bi-2223. Additions of Au, Pd and Mg to Ag sheath increased hardness and strength, while reduced elongation and electrical and thermal conductivity. In addition, microstructural investigation showed that the grain size of Ag significantly decreased with increasing content of alloying elements. The improvements in strength and hardness are believed to be due to the presence of alloying elements that lead to strengthen materials by combined effects of solid-solution, dispersion hardening and grain size hardening. Thermal conductivity of Ag and Ag alloys was evaluated in the temperature range from 77 K to 300 K, and com-pared to calculated value obtained by Wiedermann-Franz law. It was observed that the thermal conductivity decreased with increasing the content of alloying elements. Specifically, the thermal conductivity of $Ag_{0.92}Pd_{0.06}Mg_{0.02}$ alloy was measured to be $48.2W/(m{\cdot}K)$ at 77 K, which is about 6 times lower than that of $Ag(302.6W/(m{\cdot}K))$.

• 한국축산식품학회지
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• 제44권1호
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• pp.19-38
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• 2024

Meat contains high-value protein compounds that might degrade as a result of oxidation and microbial contamination. Additionally, various pathogenic and spoilage microorganisms can grow in meat. Moreover, contamination with pathogenic microorganisms above the infectious dose has caused foodborne illness outbreaks. To decrease the microbial population, traditional meat preservation methods such as thermal treatment and chemical disinfectants are used, but it may have limitations for the maintenance of meat quality or the consumers acceptance. Thus, non-thermal technologies (e.g., high-pressure processing, pulsed electric field, non-thermal plasma, pulsed light, supercritical carbon dioxide technology, ozone, irradiation, ultraviolet light, and ultrasound) have emerged to improve the shelf life and meat safety. Non-thermal technologies are becoming increasingly important because of their advantages in maintaining low temperature, meat nutrition, and short processing time. Especially, pulsed light and pulsed electric field treatment induce few sensory and physiological changes in high fat and protein meat products, making them suitable for the application. Many research results showed that these non-thermal technologies may keep meat fresh and maintain heat-sensitive elements in meat products.

• 한국지반신소재학회논문집
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• 제6권1호
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• pp.39-43
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• 2007

열융착법을 이용하여 보강과 배수기능을 가진 니들펀치 및 스펀본딩 부직포의 지오컴포지트를 제조하였다. 이 다층 부직포의 물성(인장, 인열 및 파영강도, 투수도 등)은 열융착법을 사용하여 제조될 경우 온도, 압력, 접착시간 등의 공정인자에 좌우된다. 따라서, 열융착법으로 제조된 지오컴포지트의 공정인자와 물성의 최적화는 매우 중요하다. 본 연구에서는 인공신경망(ANN)을 사용하여 지오컴포지트의 제조공정 최적화를 위한 알고리즘이 개발되었다. 지오컴포지트의 공정인자를 변화시켜 부직포 성능변화를 예측하기 위한 신경망 모사가 적용되었으며, 분석결과에 대한 제조방법의 효과를 조사하였다.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제9권1호
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• pp.1-8
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• 2020

열화상 장비는 빛이 없는 암흑 상태에서도 물체에서 발산하는 적외선을 탐지하여 이를 영상으로 제공하는 장비이다. 이러한 장점으로 기존 활용되던 군사 분야와 더불어 자동차 및 감시시스템 등 다양한 민수 분야로 활용분야가 넓어지고 있다. 본 논문에서는 상용 이미지 처리 프로세서를 이용한 열화상 이미지 처리 모듈을 제안한다. 제안한 모듈은 기존 FPGA 기반 열화상 이미지 모듈대비 약 10~20%의 성능향상을 보이며, 대기모드를 포함하면 최대 50%까지 성능향상을 보인다. 그리고 시스템 모듈화를 통한 높은 확장성을 보장한다. 뿐만 아니라 제안한 모듈은 기존의 FPGA 기반 모듈의 단점인 낮은 확장성과 재활용성을 보완함으로써 개발 기간 및 비용 단축, 다양한 응용이 가능하다. 따라서, 이러한 장점으로 다양한 고객의 요구사항 만족, 제품 설계 및 개발 일정 단축 등 다양한 이점을 얻을 것으로 기대한다.

• 한국식품영양과학회지
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• 제18권3호
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• pp.287-299
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• 1989

폭렬종 옥수수를 가열가공 처리하여 가열 처리과정중에 일어나는 단백질 및 지질의 열안정성을 검토한 결과 옥수수 가열 가공 처리에 따른 영양학적 평가의 기초자료를 얻을 수 있었다. 폭렬종 옥수수의 중성지지질은 93.5%에서 95.5%로 가열 처리 후 당지질 및 인지질의 상대적 함량이 감소하는 반면, 중성지질은 증가하였다. 전지질과 중성지질의 구성지방산은 가열처리 후 불포화 지방산이 상당히 증가하였고, 당지질과 인지질의 구성지방산은 가열처리 후 당지질의 경우 margaric acid가, 인지질의 경우 linoleic acid의 함량이 각각 증가하였다. 가열처리후 albumin분획은 lysine이 다소 증가하고, aspartic acid, arginine등은 급격히 감소하였으며, globuline분획도 이와 비슷하였다. zein분획은 glutamic acid, proline, leucine, alanine등을 적게 함유하였으며, 가열처리에 의해 함량변화가 거의 없었다. 한편, glutelin분획은 zein분획과 비교하여 lysine, histidine등을 많이 함유하는 반면, glutamic acid는 적었고, 가열처리에 의한 변화도 거의 없었다.

• The Korean Journal of Ceramics
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• 제2권4호
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• pp.246-250
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• 1996

The thermomechanical properties of materials from the system Al2O3-SiO2-TiO2(Tialite-Mullite) were investigated by correlating the thermal expansion anisotroypy, flexural strength and Young's modulus with grain size and atructural microcracking during cooling. Microcracking temperatures were determined by measuring the hysteresis of the thermal expansion anisotropy with dilatometry. Single phase Aluminium Titanate is a low strength material, while composites with more than 10 vol% mullite as second phase enhance the Young's modulus, thermal expansion coefficient and room temperature strength.

• 한국군사과학기술학회지
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• 제7권4호
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• pp.79-86
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• 2004

This paper has presented to the design results of the analog and digital signal processor for the 2nd generation thermal imaging system using $480\times6$ infrared focal plane array In order to correct non-uniformities of detector arrays, we have developed the 2-point correction method using the thermo electric cooler. Additionally, to enhance the image of low contrast and improve the detection capability, we developed the new technique of histogram processing being suitable for the characteristics of contrast distribution of thermal imagery. Through these image processing techniques, we obtained a high qualify thermal image and acquired good result.

• Preventive Nutrition and Food Science
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• 제21권2호
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• pp.160-164
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• 2016

Two onions (Sulfur-1 and Sulfur-4) cultivated with different sulfur applications were thermally processed to elucidate the effects of heat treatment on browning index and antioxidant activity. Sulfur-4 onion had higher sulfur content compared with the Sulfur-1 onion. After thermal processing, browning intensity was different between the two onions juices, with lower values observed for Sulfur-4 onion juice. This suggests that sulfur inhibits the Maillard browning reaction. The total reducing capacity of the juices increased at higher thermal processing temperatures; however, it was also lower in the Sulfur-4 onion juice. This suggests that the heat treatment of onions enhanced their antioxidant activity, but the effect was offset in the Sulfur-4 onion juice presumably due to higher sulfur content. This study indicates that sulfur, a core element for the functionality of onions, can decrease the antioxidant activity of thermally processed onions because of its potential as a Maillard reaction inhibitor.

• 한국공작기계학회논문집
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• 제18권1호
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• pp.68-75
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• 2009

A major disadvantage of thermal nanoimprint lithography(NIL) is the thermal cycle, that is, heating over glass transition temperature and then cooling below it, which requires a significant amount of processing time and limits the throughput. One of the methods to overcome this disadvantage is to make the processing temperature lower Accordingly, it is necessary to determine the effects on the processing parameters for thermal NIL at reduced temperatures and to optimize the parameters. This starts with a clear understanding of polymer material behavior during the NIL process. In this work, the squeezing and filling of thin polymer films into nanocavities during the low temperature thermal NIL have been investigated based upon a two-dimensional viscoelastic finite element analysis in order to understand how the process conditions affect a pattern quality; Pressure and initial polymer resist thickness dependency of cavity filling behaviors has been investigated.