• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.396-396
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• 2012

산업 분야에서 TiN, CrN, CrAl-N, TiAl-N과 같은 Hard 코팅들은 기계적 특성이 우수하여 절삭 공구, 기계 부품분야에서 많이 사용되고 있다. 최근 연구 동향을 살펴보면 기존에 하나 또는 두가지 합금상태의 Hard 코팅을 넘어서 제3원소, 제4원소를 첨가하여 미세 구조적 변화를 통해 기존의 우수한 특성에 고온안정성, 내식성, 내산화성 등 다양한 기능성을 부여하는 다기능성 연구가 활발히 진행 중이다. 본 연구에서는 마그네트론 스퍼터를 이용하여 고경도 코팅인 Ti-Al계열에 Si, Cu, Cr, B을 첨가함에 따른 내식특성을 확인해보았다. 성분이 균일한 코팅을 만들기 위해 Ti-Al, Ti-Al-Si, Ti-Al-Cu, Ti-Al-Cr, Ti-Al-B 단일합금타겟을 제조하여 실험을 진행하였다. 기본 물성을 확인하기 위해 경도 측정과 SEM XRD 등을 분석하였다. 내식성 평가는 동전위 테스트와 염수분무 테스트를 진행하였고 전해질은 염수와 동일한 5%-NaCl로 진행하였다. 그 결과 Ti-Al-Cr이 내식성에 강한 것으로 나타났고 염수분무 실험에서도 1200시간 이상 지속되는 성과를 보였다.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.1 s.149
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• pp.167-175
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• 2006

The purpose of this study is to clarify the expansion of functions of clothes by analyzing the characteristics of transformation, and to forecast future trends in fashion through systematization of the aforementioned analyses. Analysis of 20th century Modernism and Post-Modernism in a sociocultural sense confirms that transformation in clothes was formed by environmental, functional, deconstructive, and expressive factors. In this sense, the formative factors mentioned above conceptually include nomadic characteristics, usefulness, irregularity, and expressiveness. The nomadic characteristics found in clothes transformation signify the change of clothes into environmental nomadic everyday implements, used as tools for the body. Usefulness of clothes means that it is worn for variability, multipurpose multi-functionality, and combined multiple use. Irregularity means the clothes can change indefinitely, according to random manipulation on the wearer's part. Last of all, expressiveness conveys the designer's internal sensitivity and imagination onto an external object through the induction of various expressive factors.

• Proceedings of the Korean Fiber Society Conference
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• 2003.10b
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• pp.239-240
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• 2003

Recently, the works about antibacterial finishing have been actively investigated in textile industry because of increasing environmental pollution. Wool can easily be an medium for microorganisms growth under proper temperature and humid condition. These microorganisms can result in damages, skin irritations, and infections in wool products. For this reason, the wool materials must be protected against microorganisms in order to suppress their growth and dissemination as well as fiber damage. (omitted)

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.285-288
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• 2005

This paper is an experimental study on applicability of repairing mortar using multi-functional slag aggregate. In this study, automatic construction machinery system were adapted, and their performance were evaluated by the using of those systems. In order to verify the effect of multi-functional aggregate, two kinds of aggregate were used and compared of their physical properties. The results indicate that multi-functional aggregate appears good physical properties such as durability, permeability coefficient.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.281-284
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• 2005

This research is a study on development of section restoration mortar by multi-functional slag aggregate. Compressive strength, flexural strength and other physical properties on five standards are measured to obtain optimal addition rate (of multi-functional aggregate) and to investigate applicability of multi-functional aggregate in developing repair mortar. As the study result, the properties of repair mortar, such as compressive strength and flexural strength etc. are improved by addition of multi-functional aggregate and confirmed reduction effect of air content.

• Proceedings of the Korean Vacuum Society Conference
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• 2013.02a
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• pp.293-293
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• 2013

최근 디스플레이산업이 발달하면서 투명전도성 물질에 대한 산업의 요구도가 높아지고 있다. ITO투명전도성 박막은 낮은 비저항과 우수한 식각특성을 가지고 있어 평면표시소자, 광소자, 터치패널 그리고 가스 센서 등 다양한 분야에 응용되고 있으며 디스플레이 소자가 소형화 되어감에 따라 박막의 다기능화가 요구되고 있다. 본 실험에서는 전기적 특성과 친, 발수특성을 동시에 가지는 다기능성 ITO 박막을 연구하였다. RIE방식으로 식각을 통하여 Poly Si-wafer 표면에 미세구조를 만든 기판과 Slide Glass기판에 RF-magnetron sputtering 방법을 이용해 ITO박막을 증착하여 비교분석 하였다. ITO박막 증착시 $100{\sim}400^{\circ}C$ 열처리와 산소를 사용하지 않고 Ar 가스만을 사용하여 실험한 후 열처리온도에 따른 전기적 특성 및 접촉각에 대하여 조사하였다. 3 uL의 Di-water를 사용하여 접촉각을 측정한 결과 $400^{\circ}C$ 열처리가 된 Poly si-wafer 위에 증착된 ITO 박막에서 초-친수 특성을 나타냈으며, 그 위에 PTFE을 증착하였을 경우 12 uL의 Di-water를 사용하여 약 $150^{\circ}$ 이상의 초-발수 특성을 나타내었다. 전기적 특성은 $5.8{\times}10^{-4}$의 비 저항을 나타내었다. 이러한 전기적 특성과 친 발수 특성을 동시에 가지는 ITO 박막은 Anti-Fogging, self-Cleaning, Solar cell 및 디스플레이소자 등 다양한 산업에 이용 가능할 것으로 생각된다.

• Composites Research
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• v.24 no.1
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• pp.45-50
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• 2011

Transparent and conductive carbon nanotube on polyethylene terephthalate (PET) were prepared by dip-coating method for self-sensing multi-functional nanocomposites. The changes in the electrical and optical properties of CNT coating mainly depended on the number of dip-coating, concentration of CNT solution. Consequently, the surface resistance and transmittance of CNT coating were sensitively controlled by the processing parameters. Surface resistance of CNT coating was measured using four-point method, and surface resistance of coated CNT could be better calculated by using the dual configuration method. Optical transmittance of PET film with CNT coating was evaluated using UV spectrum. Surface properties of coated CNT investigated by wettability test via static and dynamic contact angle measurement were consistent with each other. As dip-coating number increased, surface resistance of coated CNT decreased seriously, whereas the transmittance exhibited little lower due to the thicker CNT networks layer. Interfacial microfailure properties were investigated for CNT and indium tin oxide (ITO) coatings on PET substrates by electrical resistance measurement under cyclic loading fatigue test. CNT with high aspect ratio exhibited no change in surface resistance up to 2000 cyclic loading, whereas ITO with brittle nature showed a linear increase of surface resistance up to 1000 cyclic loading and then exhibited the level-off due to reduced electrical contact points based on occurrence of many micro-cracks.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.3
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• pp.638-644
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• 2019

In this study, the fluid flow and heat transfer characteristics within sandwich panels are investigated using computational fluid dynamics. Within the sandwich panels having periodic cellular cores, air can freely move inside the core section so that the structure is able to perform multi-functional roles such as simultaneous load bearing and heat dissipation. Thus, there needs to examine the thermal and flow analysis with respect to design variables and various conditions. In this regard, ANSYS Fluent was utilized to explore the flow and heat transfer within the pyramidal truss sandwich structures by varying the truss angle and inlet velocity. Without the entry effect in the first unitcell, the constant rate of pressure and the constant rate of Nusselt number was observed. As a result, it was demonstrated that Nusselt number increases and friction factor decreases as the inlet velocity increases. Moreover, the rate of Nusselt number and friction factor was appreciable in the range of V=1-5m/s due to the transition from laminar to turbulent flow. Regarding the effect of design variable, the variation of truss angle did not significantly influence the characteristics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2009.06a
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• pp.175-175
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• 2009

최근 전자 소자의 소형화 집적화에 따른 대응 방안으로 한 개의 소자에 두가지 이상의 물리적 특성을 갖는 다기능성 소재의 개발에 많은 연구가 진행되고 있다. 다강체는 강유전성 (ferroelectricty ), 강자성 (ferromagnetism), 강탄성 (ferroelasticity) 중에서 두 개 이상의 현상을 나타내는 재료로, 이중에서도 특히 강유전성과 강자성을 동시에 나타내는 다강체가 학계 및 산업계로부터 집중적인 관심을 받으면서 최근 이 분야 연구가 국내 외적으로 매우 활발하게 이루어지고 있다. 이는 다강체를 이용하면 기존의 강유전 현상을 이용한 메모리소자인 FRAM이나 차세대 메모리소자로 주목을 받고 있는 MRAM을 결합한 새로운 방식의 메모리소자의 탄생이 가능할 수도 있기 때문이다. 즉, 일부 다강체가 나타내는 magnetoelectric (ME) 현상을 이용하면 자기적으로 신호를 인가하여 전기신호로 데이터를 저장하거나 또는 전기적으로 신호를 인가하여 자기적으로 데이터를 저장하는 것이 가능해지기 때문이다. 이 연구에서는 다강체 특성을 가지는 $Fe/BaTiO_3$ 이중박막을 IBSD(Ion Beam Sputter Deposition)을 이용하여 (111)Pt/Ti/$SiO_2/Si$ 기판에 증착을 하여 구조적, 전기적, 자기적 특성을 토론할 것이다.

• Journal of Sensor Science and Technology
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• v.13 no.5
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• pp.369-377
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• 2004

Recently, the "ride comfort" problem becomes increasingly important because of today's needs for train speedup. The concept of term "ride comfort" is equivocal. Generally it is defined as the vehicle vibration. There are many studies on evaluation method of ride comfort for railway. But each of them recommends the different assessment method and the different guidance. In general, the evaluation methods defined in the standards, such as ISO 2631 and UIC 513R, and Ride Index suggested by Sperling, have been used in the railroad. But, only one or two methods of these can be evaluated by using the commercial ride comfort measuring system. Therefore, it is necessary to develop the new ride comfort measuring system for railway with multi-function. In this paper, the generalization of "ride comfort" and the design and verification of new ride comfort measuring system for railway with multi-function have been described and the application examples has been introduced.