• Bulletin of the Korean Chemical Society
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• 제35권12호
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• pp.3465-3474
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• 2014

Porous silica particles are the most prevailing raw material for stationary phases of liquid chromatography. During a long period of time, various methodologies for production of porous silica particles have been proposed, such as crashing and sieving of xerogel, traditional dry or wet process preparation of conventional spherical particles, preparation of hierarchical mesoporous particles by template-mediated pore formation, repeated formation of a thin layer of porous silica upon nonporous silica core (core-shell particles), and formation of specific silica monolith followed by grinding and calcination. Recent developments and applications of useful porous silica particles will be covered in this review. Discussion on sub-$3{\mu}m$ silica particles including nonporous silica particles, carbon or metal oxide clad silica particles, and molecularly imprinted silica particles, will also be included. Next, the individual preparation methods and their feasibilities will be collectively and critically compared and evaluated, being followed by conclusive remarks and future perspectives.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2001년도 추계학술대회 논문집
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• pp.343-349
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• 2001

In this study we examined the method to estimate numerically the amount of the regenerated power and the excess regenerated power produced in the DC electric power supply system for the urban light rail transit system. And their economic feasibilities are also studied. For this study DC electric power supply system is simulated and the numerical analysis of the regenerated power and the excess regenerated power are conducted. The study result on the sample system shows that the facility to consume the excess regenerated power or the inverting equipment to reuse the excess regenerated power in the electric substation is feasible economically.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2010년도 춘계학술대회 논문집
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• pp.437-441
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• 2010

The SOC project such as road and railway performs a preliminary feasibility study according to the priority of the individual projects after establishing the master plans. For a preliminary feasibility study, feasibility evaluation should be performed according to the transport demand estimation and economic analysis. The feasibility of individual project will be performed by focussing on the results of analyzing economic feasibility. In case that analysis of the traffic demand and the economic feasibility every phase is performed, a lot of time and expense will be required in the course of promoting projects. So this study could give help to determine the priority of the project by intuitive method only in the phase to establish the master plan and a preliminary feasibility study.

• 한국전자통신학회논문지
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• 제1권1호
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• pp.49-55
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• 2006

Applied by periodic Stimulating Currents in Bonhoeffer -Van der Pol(BVP) model, chaotic and periodic phenomena occured at specific conditions. The conditions of the chaotic motion in BVP comprised 0.7182< $A_1$ <0.792 and 1.09< $A_1$ <1.302 proved by the analysis of phase plane, bifurcation diagram, and lyapunov exponent. To control the chaotic motion, two methods were suggested by the first used the amplitude parameter A1, $A1={\varepsilon}((x-x_s)-(y-y_s))$ and the second used the temperature parameterc, $c=c(1+{\eta}cos{\Omega}t)$ which the values of ${\eta},{\Omega}$ varied respectlvly, and $x_s$, $y_s$ are the periodic signal. As a result of simulating these methods, the chaotic phenomena was controlled with the periodic motion of periodisity. The feasibilities of the chaotic and the periodic phenomena were analysed by phase plane Poincare map and lyapunov exponent.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1995년도 추계학술대회 논문집 학회본부
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• pp.154-156
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• 1995

The effect of a periodic and a chaotic' behaviour in the Bonhoeffer-Van der Pol(BVP) oscillation of the nerve membrane driven by a periodic stimulating current $A_1=cos\;{\omega}\;t$ are investigated by numeric analysis and hardware Implementation. To control the chaotic motion, we are suggested by temperature parameter c, $c=c(1+\eta\;cos\;{\Omega}\;t)$ which the values of $\eta,\;Omega$ varied respectively. The feasibilities of chaotic and periodic phenomena were analysed by phase plane and time series.

• 조명전기설비학회논문지
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• 제19권1호
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• pp.80-86
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• 2005

본 논문에서는 시간지연을 갖는 고차모델의 축소모델로부터 요구된 주파수 설계사양을 만족하는 PID 제어기 설계방법을 제안한다. 제안된 방식은 주파수 경계조건으로부터 얻어진 2차원 입력행렬과 출력벡터를 재배열하여 구성된 선형연립방정식에 의해서 PID 제어기의 파라미터 벡터를 식별하는 방법이다. 그리고 네 개의 예제가 제안된 방식의 유용성을 나타내기 위해서 주어진다.

• 한국군사과학기술학회지
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• 제14권4호
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• pp.700-709
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• 2011

In this paper, we propose a novel method which can detect ordnance firing events in IR images. The proposed algorithm is comprised of effective target detection and robust clutter rejection methods based on the temporalspatial cooperative filter. And additional clutter reduction is performed based on the proposed two features, NTFF (Number of Temporal Filter Frames) and SNS(Size-Normalized Signal). Experimental results show the effectiveness and feasibilities of our proposed algorithm.

• 소성∙가공
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• 제16권4호
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• pp.323-328
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• 2007

The residual stress in axial direction of the steel wires has been measured by using a method based on the combination of the focused ion beam(FIB) milling and digital image correlation(DIC) program. The residual stress is calculated from the measured displacement field before and after the introduction of a slot along the steel wires. The displacement is obtained by the digital correlation analysis of high-resolution scanning electron micrographs, while the slot is introduced by FIB milling with low energy beam. The experimental procedures are described and the feasibilities are demonstrated in steel wires fabricated with different conditions. It reveals that the tensile residual stress is formed in all steel wires and this is strongly influenced by the fabrication conditions.

• 한국산업융합학회 논문집
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• 제9권3호
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• pp.179-181
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• 2006

In this paper, we present a method of fuzzy controller design for the power plant superheater in the form of bilinear system. For the steam temperature control, the input variables are constructed by the area of difference between the profiles estimated from bilinear observer and reference profiles, and the time rate of change. We estimate the control rules by T. Takagi and M. Sugeno's fuzzy model. The feasibilities of the suggested method are illustrated via the computer simulation result.

• 한국염색가공학회지
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• 제18권2호
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• pp.24-30
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• 2006

The photosensitive spiroxazine compound and the electrosensitive viologen compound were prepared to examine their practical application feasibilities and behaviors. These dyes represent corresponding chromism effects related to their own characteristics of the dye molecules. Thus, the prepared dyes were characterized and their absorption spectra were also investigated. Besides, an interest on direct spiroxazine exhaustion to the polyamide substrates and its photochromic effects within the fiber molecules were determined. The photochromic reaction on the substrates was clearly observed and its reversible decoloration behaviors responded.