• 대한전기학회논문지:시스템및제어부문D
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• 제54권1호
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• pp.17-25
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• 2005

This paper provides sufficient conditions for the robustness of Affine linear TFM(Transfer Function Matrix) MIMO (Multi-Input Multi-Output) uncertain systems based on Rosenbrock's DNA (Direct Nyquist Array). The parametric uncertainty is modeled through a Affine TFM MIMO description, and the unstructured uncertainty through a bounded perturbation of Affine polynomials. Gershgorin's theorem and concepts of diagonal dominance and GB(Gershgorin Bands) are extended to include model uncertainty. For this type of parametric robust performance we show robustness of the Affine TFM systems using Nyquist diagram and GB, DNA(Direct Nyquist Array). Multiloop PI/PB controllers can be tuned by using a modified version of the Ziegler-Nickels (ZN) relations. Simulation examples show the performance and efficiency of the proposed multiloop design method.

• 한국경영과학회:학술대회논문집
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• 한국경영과학회 2004년도 추계학술대회 및 정기총회
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• pp.31-34
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• 2004

For solving multiresponse problems, a variety of loss function approaches have been proposed assuming that a cost matrix is known and fixed. However a cost matrix is also an important factor in loss function approaches, because the optimal solution is very sensitive to the cost matrix. In this paper. we propose a novel method for adjusting the cost matrix by considering the predictive ability of the estimated response models. Simulation results for the generated data set show that the proposed method is competitive with previously reported methods.

• 대한수학회지
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• 제61권3호
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• pp.427-444
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• 2024

The matrix completion problem is to predict missing entries of a data matrix using the low-rank approximation of the observed entries. Typical approaches to matrix completion problem often rely on thresholding the singular values of the data matrix. However, these approaches have some limitations. In particular, a discontinuity is present near the thresholding value, and the thresholding value must be manually selected. To overcome these difficulties, we propose a shrinkage and thresholding function that smoothly thresholds the singular values to obtain more accurate and robust estimation of the data matrix. Furthermore, the proposed function is differentiable so that the thresholding values can be adaptively calculated during the iterations using Stein unbiased risk estimate. The experimental results demonstrate that the proposed algorithm yields a more accurate estimation with a faster execution than other matrix completion algorithms in image inpainting problems.

• 전기학회논문지
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• 제61권10호
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• pp.1508-1512
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• 2012

This paper presents a relaxed stability condition for continuous-time affine fuzzy system using fuzzy Lyapunov function. In the previous studies, stability conditions for the affine fuzzy system based on quadratic Lyapunov function have a conservativeness. The stability condition is considered by using the fuzzy Lyapunov function, which has membership functions in the traditional Lyapunov function. Based on Lyapunov-stability theory, the stability condition for affine fuzzy system is derived and represented to linear matrix inequalities(LMIs). And slack matrix is added to stability condition for the relaxed stability condition. Finally, simulation example is given to illustrate the merits of the proposed method.

• 대한수학회보
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• 제59권5호
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• pp.1215-1235
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• 2022

In this paper we study Szegö kernel projections for Hardy spaces in quaternionic Clifford analysis. At first we introduce the matrix Szegö projection operator for the Hardy space of quaternionic Hermitean monogenic functions by the characterization of the matrix Hilbert transform in the quaternionic Clifford analysis. Then we establish the Kerzman-Stein formula which closely connects the matrix Szegö projection operator with the Hardy projection operator onto the Hardy space, and we get the matrix Szegö projection operator in terms of the Hardy projection operator and its adjoint. At last, we construct the explicit matrix Szegö kernel function for the Hardy space on the sphere as an example, and get the solution to a Diriclet boundary value problem for matrix functions.

• Journal of Advanced Marine Engineering and Technology
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• 제35권2호
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• pp.271-277
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• 2011

이 연구에서는 유전알고리즘을 이용하여 강봉의 감쇠행렬을 산출하는 방법을 제안하다. 감쇠행렬이 강성행렬과 비례한다는 가정을 전제로 각 요소강성행렬에 임의의 정수를 곱하여 감쇠행렬을 구성하여 주파수응답함수를 구성하고, 이를 실험 주파수응답함수와 비교한 값을 목적함수로 하여 목적함수가 가장 작은 정수의 감쇠행렬을 구한다. 비감쇠 해석의 경우보다 목적함수의 값이 약 1/60로 작아지는 것을 알 수 있었다. 이를 이용하면 큰 구조물의 감쇠가 큰 일부 부분구조물을 떼어내어 감쇠행렬을 구할 수 있어 구조물의 감쇠진동해석을 하는데 도움이 될 것으로 사료된다.

• 호남수학학술지
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• 제42권3호
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• pp.425-447
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• 2020

The family of q-Konhauser matrix polynomials have been extended to Konhauser matrix polynomials. The purpose of the present work is to show that an extension of the explicit forms, generating matrix functions, matrix recurrence relations and Rodrigues-type formula for these matrix polynomials are given, our desired results have been established and their applications are presented.

• 한국HCI학회:학술대회논문집
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• 한국HCI학회 2008년도 학술대회 2부
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• pp.310-316
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• 2008

국내외 기업들이 기업포탈(Enterprise Portal)에 대한 관심이 높아지연서 사용자 인터페이스(User Interface)에 대한 중요성이 인식되고 있다. 본 논문에서는 기업포탈(Enterprise Portal)에 대하여 살펴보고, 현행시스템에 대한 사용자의 개선요구사항을 조사, 분석하였다. 사용자 분석결과와 Checklist 평가를 통하여 UI Checklist Matrix 를 작성하였다. Matrix 의 가로축은 사용자 요구분석결과인 Layout, Navigation, Information, Function, Visibility, Interaction 6 가지 항목으로 구성된다. 세로축은 학습성, 효율성, 정확성, 접근성, 일관성, 즉시성, 통합성, 개인화, 기술, 표준화 10 가지 항목이 있다. 가로와 세로 항목이 만나는 곳에 중요도를 표시하고 세부항목을 정의한다. Matrix 가 반영된 가이드라인을 작성하고 가이드라인에 따라 업무화면을 설계하고 Matrix 로 평가한다. 본 연구는 보험사의 차세대 시스템 구축 프로젝트에서 진행된 내용으로 1 년여 기간 동안 업무담당자들과 업무정의에서부터 긴밀한 협조 하에 진행되었다.

• 시스템엔지니어링학술지
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• 제1권2호
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• pp.56-62
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• 2005

In this study, we first define user requirements to fulfill the reconnaissance and the search missions, by analyzing the system characteristics and operation environment. By investigating the design technology level, the development and procurement costs, the strong system design concepts and possible alternatives will be proposed. To analyze the system requirements, the Quality Function Deployment of the systems engineering approach will be implemented. The promising design alternatives that satisfy the user requirements are extracted by constructing the Morphological Matrix, then the best design concept will be obtained using the Pugh Concept Selection Matrix and the TOPSIS(Technique of Order Preference by Similarity to Ideal Solution).

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제25권3호
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• pp.107-116
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• 2021

We introduce optimization algorithms using Bregman Divergence for solving non-negative matrix factorization (NMF) problems. Bregman divergence is known a generalization of some divergences such as Frobenius norm and KL divergence and etc. Some algorithms can be applicable to not only NMF with Frobenius norm but also NMF with more general Bregman divergence. Matrix Factorization is a popular non-convex optimization problem, for which alternating minimization schemes are mostly used. We develop the Bregman proximal gradient method applicable for all NMF formulated in any Bregman divergences. In the derivation of NMF algorithm for Bregman divergence, we need to use majorization/minimization(MM) for a proper auxiliary function. We present algorithmic aspects of NMF for Bregman divergence by using MM of auxiliary function.