• International Journal of Control, Automation, and Systems
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• 제5권4호
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• pp.364-371
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• 2007

In this paper, we describe the synthesis of robust and non-fragile $H^{\infty}$ state feedback controllers for linear systems with affine parameter uncertainties, as well as a static state feedback controller with poly topic uncertainty. The sufficient condition of controller existence, the design method of robust and non-fragile $H^{\infty}$ static state feedback controller with fuzzy compensator, and the region of controllers that satisfies non-fragility are presented. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed loop system in spite of controller gain variations within a resulted polytopic region.

• International Journal of Control, Automation, and Systems
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• 제1권4호
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• pp.503-510
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• 2003

This paper describes the synthesis of robust and non-fragile $H^{i~}$state feedback controllers for linear varying systems with time delay and affine parameter uncertainties, as well as static state feedback controller with structural uncertainty. The sufficient condition of controller existence, the design method of robust and non-fragile $H^{i~}$static state feedback controller, and the region of controllers satisfying non-fragility are presented. Also, using some change of variables and Schur complements, the obtained conditions can be rewritten as parameterized Linear Matrix Inequalities (PLMIs), that is, LMIs whose coefficients are functions of a parameter confined to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed loop system in spite of time delay and controller gain variations within a resulted polytopic region.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2001년도 ICCAS
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• pp.75.1-75
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• 2001

In this paper, we provide the synthesis of non-fragile H$\infty$ output feedback controllers for linear systems with affine parameter uncertainties, and dynamic output feedback controller with structural uncertainty. The sufficient condition of controller existence, the design method of robust and non-fragile H$\infty$ output feedback controller, and the region of controllers which satisfies non-fragility are presented. Also using some change of variables and Schur complements, the obtained condition to a compact set. We show that the resulting controller guarantees the asymptotic stability and disturbance attenuation of the closed ...

• 전자공학회논문지CI
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• 제46권1호
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• pp.128-135
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• 2009

동영상에서 시공간상 일정한 위상을 갖는 윤곽선을 정합시켜 물리적 공간에서의 동일한 위치를 추적하는 방법은 명암이 일정한 윤곽선을 정합시키거나 일정한 명암을 전제로 추적하는 방법에 비해 정확성이 높고 조명조건에 대해 안정된 특성이 있다. 본 논문에서는 이러한 성질을 이용하여 조명변화와 노이즈에 강인하게 카메라의 움직임을 추정하는 기법을 소개한다. 우선, 가버 필터뱅크를 사용하여 공간적으로 여과된 연속영상으로부터 계산된 위상의 크기를 기반으로 필터의 방향과 수직인 곳의 광류를 구한 후, 최소제곱법을 적용하여 어파인 모델에 상응하는 카메라의 움직임 파라미터를 구한다. 실험을 통하여 이러한 방법은 조명조건의 변화를 야기하는 디스플레이 기기를 피사체로 하여 카메라의 위치변화를 추정하는 방식의 영상기반 포인팅 디바이스에도 적용될 수 있음을 보인다.

• 대한수학회지
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• 제54권6호
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• pp.1759-1786
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• 2017

We examine the moduli space of oriented locally homogeneous manifolds of Type ${\mathcal{A}}$ which have non-degenerate symmetric Ricci tensor both in the setting of manifolds with torsion and also in the torsion free setting where the dimension is at least 3. These exhibit phenomena that is very different than in the case of surfaces. In dimension 3, we determine all the possible symmetry groups in the torsion free setting.

• 대한수학회보
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• 제61권3호
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• pp.849-866
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• 2024

In this paper, we study the rectifying curves in multiplicative Euclidean space of dimension 3, i.e., those curves for which the position vector always lies in its rectifying plane. Since the definition of rectifying curve is affine and not metric, we are directly able to perform multiplicative differential-geometric concepts to investigate such curves. By several characterizations, we completely classify the multiplicative rectifying curves by means of the multiplicative spherical curves.

• 전자공학회논문지C
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• 제36C권7호
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• pp.56-64
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• 1999

본 논문에서는 연속 어핀 Takagi-Sugeno 퍼지 시스템의 안정도를 판정하는 새로운 방법을 제안한다. 제안된 방법은 최근 각광을 받고 있는 선형 행렬 부등식이라는 컨벡스 최적화 기법을 이용하여 쉽게 구현할 수 있다. 우선 어핀 Takagi-Sugeno 퍼지 시스템이 안정하도록 되는 조건을 유도하고 이를 선형 행렬 부등식의 형태로 변형하고 수치적 접근방식을 제안한다. 끝으로 컴퓨터 모의 실험을 통하여 제안한 방법의 타당성을 확인한다.

• 응용통계연구
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• 제24권1호
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• pp.83-92
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• 2011

주식은 그 자체로도 투자의 대상이며, 또한 옵션의 기초자산으로서 옵션의 가격을 평가하는 기본도구로 사용되고 있기에, 주식에 대한 정확한 예측값 도출은 매우 중요하다고 불 수 있다.주식의 가치평가를 위하여 기존 연구들은 대표적으로 GARCH 류의 모형과 SV(stochastic volatility, 확률변동성)류의 모형을 사용하였다. 본 연구에서는 SV 모형에 대해서 초점을 맞추어 KOSPI200 지수를 실증분석하였다. 특히 Durham (2008)의 방법론에 따라서 로그 SV 모델에 변동성지수(VKOSPI 지수)를 추가로 고려하여 모델의 정확도 향상을 기대하였다. VKOSPI 지수는 KOSPI200의 옵션으로부터 계산된 미래에 대한 기대 변동성으로, 주식과 옵션간의 유기적 관련성을 바탕으로 추정하기에 그 의미가 있다. 자료는 2003년 1월2일부터 2010년 9월 24일을 기간으로 사용하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 학술회의 논문집 정보 및 제어부문 A
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• pp.315-318
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• 2003

This paper proposes a switching control method applicable to any affine, 2nd order nonlinear system with single input. The key contribution is to develop a control design method which uses a piecewise continuous Lyapunov function non-increasing at every discontinuous point. The proposed design method requires no restrictions except full state availability. To obtain a non-increasing, piecewise continuous Lyapunov function, we change the sign of off-diagonal term s of the positive definite matrix composing the former Lyapunov function according to the sign of the Inter-connection term. And we use the solution of inequalities which guarantee each Lyapunov function is non-increasing at any discontinuous point.

• Korea-Australia Rheology Journal
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• 제16권2호
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• pp.91-99
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• 2004

For the Rouse chain composed of infinite number of beads (continuous limit), conformational changes during the creep and creep recovery processes was recently analyzed to reveal the interplay among all Rouse eigenmodes under the constant stress condition (Watanabe and Inoue, Rheol. Acta, 2004). For completeness of the analysis of the Rouse model, this paper analyzes the conformational changes of the discrete Rouse chain having a finite number of beads (N = 3 and 4). The analysis demonstrates that the chain of finite N exhibits the affine deformation on imposition/removal of the stress and this deformation gives the instantaneous component of the recoverable compliance, $J_{R}$(0) = 1/(N-l)v $k_{B}$T with v and $k_{B}$ being the chain number density and Boltzmann constant, respectively. (This component vanishes for N\longrightarrow$\infty$.) For N = 2, it is known that the chain has only one internal eigenmode so that the affinely deformed conformation at the onset of the creep process does not change with time t and $J_{R}$(t) coincides with $J_{R}$(0) at any t (no transient increase of $J_{R}$(t)). However, for N$\geq$3, the chain has N-l eigenmodes (N-l$\geq$2), and this coincidence vanishes. For this case, the chain conformation changes with t to the non-affine conformation under steady flow, and this change is governed by the interplay of the Rouse eigenmodes (under the constant stress condition). This conformational change gives the non-instantaneous increase of $J_{R}$(t) with t, as also noted in the continuous limit (N\longrightarrow$\infty$).X>).TEX>).X>).