• Korean Journal of Mathematics
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• 제24권1호
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• pp.1-13
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• 2016

This paper shows that the solutions to the perturbed functional dierential system $$y^{\prime}=f(t,y)+{\int_{t_0}^{t}}g(s,y(s),Ty(s))ds$$ have uniformly Lipschitz stability and asymptotic property. To sRhow these properties, we impose conditions on the perturbed part ${\int_{t_0}^{t}}g(s,y(s),Ty(s))ds$ and the fundamental matrix of the unperturbed system $y^{\prime}=f(t,y)$.

• 충청수학회지
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• 제29권3호
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• pp.429-442
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• 2016

In this paper we show that the solutions to the perturbed differential system $$y^{\prime}=f(t,y)+{\int}_{to}^{t}g(s,y(s),Ty(s))ds$$ have uniformly Lipschitz stability and asymptotic behavior by imposing conditions on the perturbed part $\int_{to}^{t}g(s,y(s),Ty(s))ds$ and the fundamental matrix of the unperturbed system y' = f(t, y).

• 대한가정학회지
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• 제33권5호
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• pp.187-196
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• 1995

This study was performed was performed to identify the predictability of maternal attitude from infant's temperament and mother's mental stability. It was focused on the comparison of the degree of predictability between infant's temperament and mother's mental stability. Data were collected from sixty-five mothers of infants. Mother's affective attitude was explained by both the maternal mental stability and the infant's temperament. After controlling the effect of mental stability, infant's temperament could explain the affective attitude. This result meant that infant's temperament showed the powerful effect on the maternal affective attitude. However, maternal controlling attitude was only explained by her mental stability but not by infant's temperament. This meant that infant's temperament could not explain mother's controlling behavior. However, interactive effect between infant's sex and temperament was found in the controlling attitude. Mothers showed more controlling attitude toward the difficult boys but not toward the difficult girls.

• 전기학회논문지
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• 제61권10호
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• pp.1387-1392
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• 2012

These days people use a lot of electric power, because industry advancement and a standard of living is elevated. So voltage stability analysis and control problems are very important in these days. U.S.A has already developed voltage stability analysis program, and use it on power transmission scheme such as generator overhaul, transmission line off and so on. So voltage stability analysis is more and more interested in Korea, too. In this paper, we introduce a standard theory of voltage stability analysis and real time voltage stability analysis program that use sPMU(Satellite Phasor Measurement Unit). And we also introduce the calculation result about voltage stability in Jeju power transmission system.

• 유기물자원화
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• 제14권2호
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• pp.63-70
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• 2006

본 연구에서는 폐기물매립지의 안정화 정도를 용이하게 평가하기 위하여 매립폐기물의 분해정도를 수치화 할 수 있는 매립지의 안정화 지수 개발을 목적으로 하였다. 안정화 지수를 개발하기 위하여 50개소의 사용종료 매립지를 대상으로 침출수 수질, 매립가스 조성, 매립폐기물의 물리화학적 특성 자료를 수집하여 이들의 매립연령별 환경특성을 고찰하였다. 그리고 이들 환경지표중 폐기물매립지의 안정화와 상관도가 높은세부 환경지표로서 침출수의 BOD/CODcr, 발생가스중의 $CH_4$농도, 매립폐기물의 C/N가 안정화 지표로 선정하였다. 각 지표에 대한 매립연령별 추세선을 이용하여 지수화한 결과 매립지 안정화 지수로 다음과 같은 식을 얻을 수 있었다. $$I_{LS}=S_L+S_G+S_W$$ $$S_L=-\{4.892+16.587{\cdot}ln[BOD/COD_{Cr]\}$$ $$S_G=53.872-12.782{\cdot}ln[CH_4]$$ $$S_W=79.382-20.013{\cdot}ln[C/N]$$ (단, $S_L$, $S_G$, and $S_W$는 각각 33.3점이 최대값이다.) 여기서, $I_{LS}$ : 매립지 안정화 지수 $S_L$ : 침출수의 안정화 점수 $S_G$ : 매립가스의 안정화 점수 $S_W$ : 폐기물의 안정화 점수.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.95.1-95
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• 2001

This paper is concerned with a novel S-stability (stochastic-stability) concept in linear time-invariant stochastic systems, where a stochastic mode in dynamics depends on both the external disturbance and the inner-parameter variations. This leads to an EAG (eigenstructure assignment gaussian) problem; that is, the problem of associating S-eigenvalues (stochastic-eigenvalues), S-eigenvectors (stochastic-eigenvectors), and their PDFs (probability density functions) with the stochastic information of the systems with the required stochastic specifications. These results explicitly characterize how S-eigenvalues, S-eigenvectors and their PDFs in the complex plane may impose S-stability on stochastic systems.

• 한국수학교육학회지시리즈B:순수및응용수학
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• 제23권1호
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• pp.1-12
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• 2016

This paper shows that the solutions to the perturbed differential system $y^{\prime}=f(t, y)+\int_{to}^{t}g(s,y(s),Ty(s))ds+h(t,y(t))$ have asymptotic property and uniform Lipschitz stability. To show these properties, we impose conditions on the perturbed part $\int_{to}^{t}g(s,y(s),Ty(s))ds+h(t,y(t))$, and on the fundamental matrix of the unperturbed system y' = f(t, y).

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1987년도 한국자동제어학술회의논문집(한일합동학술편); 한국과학기술대학, 충남; 16-17 Oct. 1987
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• pp.827-831
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• 1987

The analysis of a certian example and simulations given in the previous sections show that the modified FKA is more stable than the standard FKA without loss of the performance of it. The general analysis of modified FKA's numerical stability is the open problem with more simulations in order to prove the stability of it.

• 한국지능시스템학회논문지
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• 제7권3호
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• pp.72-80
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• 1997

A new design method for Takagi-Sugeno (T-S in short) fuzzy controller which guarantees global asymptotic stability and satisfies a desired performance is proposed in this paper. The method uses LMI(Linear Matrix Inequality) approach to find the common symmetric positive definite matrix P and feedback fains K/sub i/, i= 1, 2,..., r, numerically. The LMIs for stability criterion which treats P and K'/sub i/s as matrix variables is derived from Wang et al.'s stability criterion. Wang et al.'s stability criterion is nonlinear MIs since P and K'/sub i/s are coupled together. The desired performance is represented as $ LMIs which place the closed-loop poles of $ local subsystems within the desired region in s-plane. By solving the stability LMIs and pole placement constraint LMIs simultaneously, the feedback gains K'/sub i/s which gurarntee global asymptotic stability and satisfy the desired performance are determined. The design method is verified by designing a T-S fuzzy controller for an inverted pendulum with a cart using the proposed method.

• 대한수학회논문집
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• 제18권1호
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• pp.133-149
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• 2003

Local stability of steady states of an epidemic model is considered. An age structured S-I-R epidemic model with separable inter-cohort force of infection with external force is considered. Stability result for the nontrivial steady states is obtained.