• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.05a
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• pp.193-196
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• 2005

유기발광소자의 발광층의 두께에 따른 임피던스의 변화를 살펴보았다. 임피던스는 두께에 따라 저항의 변화에 따른 의존성을 보이며, 그에 따른 임피던스와 Cole-Cole 반원의 변화, 두께에 따른 $1/\tau$ 의 변화를 살펴보았다. 발광층의 두께는 각각 100, 200, 300 nm의 두께로 열증착하여 실험하였고, 소자의 구조는 $ITO/Alq_3/Al$의 구조로 측정 하였다. 유기발광소자의 발광층인 $Alq_3$의 두께가 증가함에 따라 임피던스의 크기가 증가하고, 위상각의 크기는 100nm의 경우 0V에서 용량성을 보이다가 6~10V까지 부성저항특성을 나타낸 후 약 22V에서 저항성을 나타내고, 200과 300 nm의 경우 12V까지 용량성을 나타내다 이후 22V 근방에서 $0^{\circ}$에 가까워지며 저항성을 나타내는 것을 알 수 있었다. 또한 두께에 따른 Cole-Cole 반원을 살펴보면 두께가 증가할수록 반원의 크기가 증가하는 것을 알 수 있으며, 이를 통해 간단한 등가회로를 예측할 수 있었다. 그리고 벌크내의 용량성$(C_p)$을 측정하여 두께의 증가에 따라 $C_p$ 값이 감소하는 것을 알 수 있었다.

• Coupled systems mechanics
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• v.3 no.1
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• pp.89-110
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• 2014

In this work we provide the theoretical formulation, discrete approximation and solution algorithm for instability problems combing geometric instability at large displacements and material instability due to softening under combined thermo-mechanical extreme loads. While the proposed approach and its implementation are sufficiently general to apply to vast majority of structural mechanics models, more detailed developments are provided for truss-bar model. Several numerical simulations are presented in order to illustrate a very satisfying performance of the proposed methodology.

• Bulletin of the Korean Chemical Society
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• v.23 no.3
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• pp.413-416
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• 2002

The dielectric responses of 10 and 40 wt% siloxane-epoxy copolymers were investigated in temperature range near the glass transition of polydimethylsiloxane at which the dielectric transitions were also observed. On the other hand, the pure epoxy did not show any dielectric transition in measurement temperature range -90 to 150 $^{\circ}C.$ The experimental data showed that for the copolymer investigated, the temperature-frequency super-position principle could be applied to the dielectric response. From the Cole-Cole equation, the dielectric relaxation of the 10 wt% siloxane near the glass transition temperature resulted in a broad distribution with ${\beta}=$ 0.19 and the relaxation time at -70 $^{\circ}C$ was 5.3 ${\times}$ $10^{-2}$s. The glass transition temperature, 188 K, was estimated by using WLF relation, which was consistent with the data presented in experiment.

• Journal of electromagnetic engineering and science
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• v.10 no.4
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• pp.231-236
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• 2010

This study proposes a temperature compensation method of the complex permittivities of biological tissues and organs. The method is based on the temperature dependence of the Debye model of water, which has been thoroughly investigated. This method was applied to measured data at room temperature for whole blood, kidney cortex, bile, liver, and heart muscle. It is shown that our method can compensate for the Cole-Cole model using measured data at 20 $^{\circ}C$, given the Cole-Cole model based on measured data at 35 $^{\circ}C$, with a root-mean-squared deviation of 3~11 % and 2~6 % for the real and imaginary parts of the complex permittivities, respectively, among the measured tissues.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.06a
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• pp.409-410
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• 2008

We studied dielectric properties of Organic Light-emitting Diodes(OLEDs) depending on applied voltage of AF(Amorphous Polytetrafluoroethylene), material of hole injection layer in structure of ITO/hole injection layer (AF)/Al. AF is deposited 5 [nm] as deposition rate of 0.1~0.2 [$\AA$/s] in high vacuum of $5\times10^{-6}$ [Torr]. In result of these studies, we can know dielectric properties of OLEDs. The impedance decreases as the applied voltage increases and the Cole-Cole plots of devices are decreases as the applied voltage increases.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2005.07a
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• pp.252-253
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• 2005

The dielectric relaxation properties of $^{60}Co$ gamma-ray irradiated Poly(vinylidene fluoride) (PVDF) containing various antioxidants have been investigated for radiation degradation. Cole-Cole's circular arcs were induced from the results of temperature and frequency dependency of dielectric properties with radiation dose. The magnitude of polarization of PVDF was decreased by adding antioxidants. The values of dielectric relaxation intensity calculated by using the Cole-Cole's circular arcs showed a certain tendency for radiation degradation.

• Journal of the Korean Physical Society
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• v.73 no.12
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• pp.1873-1878
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• 2018

We have investigated the ionic conductivity and dielectric relaxation in $Li_2B_4O_7$ (LBO) and $Li_2O-B_2O_3-Ta_2O_5$ (LBTO) glasses. The sample was synthesized by using the melt quenching method. The frequency dependence of the electrical data from the LBO and LBTO glasses has been analyzed in the frameworks of the impedance Cole-Cole formalism and the universal power-law representation driven by the modified fractional Rayleigh equation. The potential barriers in the LBO and the LBTO glasses turn out to be the same. Comparing with the dc and ac activation energies of the LBO glass, these energies of the LBTO glass decrease due to the increasing Coulomb interaction of inter-cationic interaction.

• Journal of Ceramic Processing Research
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• v.13 no.spc2
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• pp.163-165
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• 2012

Impedance spectroscopy informs electrical properties of materials as accumulated charges, contact status between electrode and organic materials. We carried out impedance spectroscopy of organic light-emitting diodes as ITO/Alq3(60 nm)/Al on temperatures from 10 K to 300 K. The result described Z'-Z" plot, cole-cole plot and dielectric relaxation time τ. Z'-Z" plot means that real and imaginary part of materials in organic and electrode by frequencies and temperature. Z' as real part of impedance by applied frequency depending on temperature shows the plateau in low frequency region as Rs+ Rp and over 100 kHz in high frequency region as Rs. Cole-cole plot shows resistance of materials in equivalent circuit of the device by temperatures. And equivalent circuit and dielectric relaxation could be accomplished by using the complex impedance analysis.

• Journal of the Korean Data and Information Science Society
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• v.26 no.4
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• pp.857-864
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• 2015

By Wikipedia, data mining is the computational process of discovering patterns in huge data sets involving methods at the intersection of association rule, decision tree, clustering, artificial intelligence, machine learning. Clustering or cluster analysis is the task of grouping a set of objects in such a way that objects in the same group are more similar to each other than to those in other groups. The similarity measures being used in the clustering may be classified into various types depending on the characteristics of data. In this paper, we computed bounds for similarity measures based on the probabilistic interestingness measure with partially marginal probability such as Peirce I, Peirce II, Cole I, Cole II, Loevinger, Park I, and Park II measure. We confirmed the absolute value of Loevinger measure wasthe upper limit of the absolute value of any other existing measures. Ordering of other measures is determined by the size of concurrence proportion, non-simultaneous occurrence proportion, and mismatch proportion.

• Korean Journal of Human Ecology
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• v.3 no.1
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• pp.1-14
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• 1994

This study is carried out to develope parent education methodology by analysing "${\acute{E}}cole$ des Parents" of France. To study this subject we approach by following three methodes. Firstly, we examined bibliographes to find out motivation of initiative caused from hystological and sociological circumstance. Secondly, to analyse chronological developement and modification of "${\acute{E}}cole$ des Parents" we interviewed with three periods of persons : founder, developer and actually working animators. In addition, we riviewed three hundred eighty volumes of $\underline{{\acute{E}}cole\;des\;Parents}$, from first jurnals to october, 1993. Thirdly, this study were approached by participant observation in actual activities, and by analyse statstical records and subject of articals. In results, we noticed following caractors working in french parent education system. All the regional "${\acute{E}}cole$ des Parents" are alined with "$F{\acute{E}}d{\acute{E}}ration$ Nationale des ${\acute{E}}cole$ des Parents et des ${\acute{E}}ducateurs$"(F.N.E.PE.) in educational polish but activities and methodes of education are independant with F.N.E.P.E., and in most different regional "${\acute{E}}cole$ des Parents" focussed the educational programes to the middle class families in economic point of view. these programes adjust very rapidly systematicaly to social requirment due to successed intensive research. Mordern programs tend to contain all members of family in stead of targeting only maternal members. Methodes of education by lectures and speechs only to deliver information also replaced by discussion, forum and groop animation to induce self-correction. We propose that the systems of FNEPE can be ideal models to solve many actual problems facing in Korean parent education systemes.