• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.05a
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• pp.6.2-8
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• 1996

The NO$_2$ GAS-detection characteristic of CuTBT (Copper-tetra-tert-butylphtha1ocyanine) LB films were investigated through a study of current-voltage (I-V) characteristics with a variation of number N of interdigital electrodes (N=1∼25). A concentration of 200ppm NO$_2$ gas was used. It was found that a conductance G increases monotonically as the number of interdigital electrode increases, and a sensitivity $\Delta$G ($\Delta$G=G$\_$gas//G$\_$air/) is at least higher than 50 and stable. As far as a sensitivity is concerned, the sensitivity when N=26 is greater than that when N=1 by 70 or so. It indicates that the number of interdigital electrodes affects the currents, sensitivity and stability.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.11a
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• pp.118-121
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• 1994

The NO$_2$ gas-detection characteristics were investigated using the functional organic Langmuir-Blodgett(LB) film of Copper-tetra-tert-butylphalocyanine(CUTBP). The optimum conditions for a film deposition were obtained through a study of $\pi$-A isotherm and the deposited film status was confirmed by ellipsometry measurements. In the NO$_2$ response experiments, first of all, the proper number of layer was obtained by a change of the electrical conductivities depending on the number of layer when the film is exposed to the gas. And response time, recovery time, and reproducibility were measured on it. On the other hand, how the NO$_2$ gas interacts to the LB film was studied by UV/visible absorption spectra.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.1074-1077
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• 2002

Biomechanical behavior of the human femur is very important in various clinical situations. In this study, the data of FE models based on DICOM file exported from Computed tomography(CT). We generated FE models(voxel model, tetra model) of human femur using CT slide image. We compared them with Yon Mises stress results derived from finite element analysis(FEA). Comparing the two models, we found a correlation of them. As a result, the tetra model based proposed marching cube algorithm is a valid and accurate method to predict parameters of the complex biomechanical behavior of human femur.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.342-342
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• 2011

방사광을 이용한 흡수스펙트럼으로부터 그래핀 표면 위 TCPP(Tetra(4-carboxyphenyl)porphine) 유기 분자의 흡착구조에 대하여 연구하였다. 순수한 그래핀 표면의 비활성도는 소자응용 분야에 있어 그 영역을 제한할 수 있는 하나의 걸림돌이 되고 있다. 이를 극복하기 위해 유기분자막의 초기 흡착을 이용한 다양한 방법이 시도되어왔다. 그 중 TCPP 분자막을 이용한 그래핀 표면의 기능성 및 그 우수성을 이미 보고한 바 있다. 그러나 그 분자의 흡착구조에 대해 밝혀진 바 없다. 그래핀 표면과 분자간의 흡착 메커니즘 및 분자 상호간의 역학관계는 그 흡착구조의 규명으로부터 얻어질 수 있는데, 본 연구에서는 C 1s K-edge에 대한 NEXAFS 스펙트럼을 이용하여 TCPP 분자가 그래핀과 평행한 방향으로 흡착됨을 알 수 있었다. 이는 또한 분자흡착량의 증가에 따른 AFM 이미지와 일관됨을 알 수 있었다.

• Proceedings of the Korean Information Science Society Conference
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• 2007.10d
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• pp.376-380
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• 2007

본 논문은 산업용으로 널리 사용되고 있는 DNP3.0(Distributed Network Protocol)과 국가 긴급 재난망으로 사용되고 있는 TETRA(Terrestrial Trunked Radio)간의 소프트웨어 및 하드웨어 인터페이스를 정의하였다. 전재 사용중인 DNP3.0의 전송 방식의 문제점을 살펴보고, 이에 대한 해결방안으로써 TETRA를 제안함으로써 좀 더 안정적인 데이터의 전송과 TETRA 망의 이용 극대화를 이룰 수 있다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1996.11a
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• pp.417-420
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• 1996

We have investigated air/200ppm NO$_2$ gas-detector characteristics of using CuTBP (Copper-tetra-tert-butylphthalocyanine) chemiresistor devices. The CuTBP films were made by Langmuir-Blodgett (LB) techniques. Sensitivity, response time, recovery time, and repoducibility of the devices were measured by current-voltage characteristics. To increase sensitivity, interdigital electrode was used. It was found that a conductance G increases monotonically as the number of interdigital electrode increases, and a Sensitivity, Reproducibility is stable. As far as a current is concerned, the current when N=25 is greater than that when N=1 by 70 or so. It indicates that the number of interdigital electrodes affects the current, sensitivity and stability We have also investigated applicability of the CuTBP chemiresistor device for a gas detector.

• The Journal of the Korea institute of electronic communication sciences
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• v.5 no.3
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• pp.294-303
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• 2010

Radiocommunication systems is very useful method to configure the unified command communication system in case of the disasters. Currently Korea's radiocommunication network against the disasters is operating with TETRA system. This system is very powerful with multifunction to apply in the disaster situation. However, Korea's disaster radiocommunication system is so important to keep and maintain survivability. Therefore this paper study on the alternate systems to TETRA system.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1994.05a
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• pp.79-82
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• 1994

We have manufacture Copper-tetra-tert-butylphalocyanine (CuTBP)Langmuir-Blodgett(LB) films, which is known be sensitive to NO$_2$ gab. A response of these films to the NO$_2$ gab was studied. A surface pleasure of 25mN/m was obtained as a proper one for a film deposition. A deposited film status was identified with Uv/visible absorption spectra, ellipsometry measurements, and current-voltage(I-Y) characteristics. The NO$_2$ gas response experiments under 200ppm conducentration show that there are increment of electrical conductivity by 12 times, 5 seconds of response time, and 5 seconds of response time, and 90 seconds of recovery time.

• Proceeding of EDISON Challenge
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• 2016.03a
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• pp.190-194
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• 2016

자연에서 안정적이고 경제성이 높은 구조로 벌집 구조가 많이 언급이 된다. 이러한 벌집 구조의 특징으로 인해 많은 공학자들이 그 구조를 모방하여 적용하고 있다. 벌집 구조에도 다양한 종류가 존재하지만 그 중 음의 푸아송 비(Poisson's ratio)를 갖는 Chiral Honeycomb 구조가 많이 연구되고 있다. 푸아송 비는 물질이나 구조의 고유한 물성치로 종, 횡 방향의 변형율로 나타내며 이 값으로 외부 조건으로부터의 변형을 예측 할 수 있게 된다. 흔히 푸아송 비는 양의 값을 가지지만 Chiral Honeycomb 구조는 음의 푸아송 비를 가져 기존의 구조와는 다른 기계적 성질을 가지게 된다. 이 논문에서는 Chiral Honeycomb 구조 중에서도 4개의 관절(ligament)를 가지는 Tetra Chiral Honeycomb 구조에 대해 EDISON용 CASADsovler 프로그램을 통해 유한 요소 해석을 수행하여 등가 물성치를 구해 보았으며 기존 실험의 값들과 비교를 통해 해석을 위해 필요한 적절한 대표 체적에 대해 확인해 보았다.

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.905-909
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• 1999

Reaction of tetrahomodioxa p-phenylcalix[4]arene with ethyl bromoacetate and potassium carbonate in ace-tone leads to the title tetra ester derivative, 7,13,21,27-tetra-phenyl-29,30,31,32 -tetrakis(ethoxycarbonyl)meth-oxy-2,3,16,17-tetrahomo-3,17-dioxacalix[4]arene, its structure was determined by NMR spectra as 1,4-alternate conformation. The molecular structure has been solved by X-ray diffraction methods. The molecule has a conformation with pseudo center of symmetry. The benzene ring A is up, ring C is down, B and D rings are flat with respect to the plane of the macrocyclic ring.