• Journal of the Institute of Electronics Engineers of Korea CI
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• v.41 no.3
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• pp.79-90
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• 2004

Systematical robust stability analysis and design scheme for the feedback linearization control systems via fuzzy modeling are proposed. It is considered that uncertainty and disturbances are included in the Takagi-Sugeno fuzzy models representing the nonlinear plants. Robust stability of the closed system is analyzed by casting the systems into the diagonal norm bounded linear differential inclusions and by converting the analysis and design problems into the linear matrix inequality optimization, a numerical method for finding the maximum stable ranges of the fuzzy feedback linearization control gains is also proposed. To verify the effectiveness of the proposed scheme, the robust stability analysis and control design examples are given.

• Computational Structural Engineering
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• v.20 no.3
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• pp.25-32
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• 2007

CATIA V5 해석기능에 대하여 간략히 소개하고자 한다. 설계자용 해석뿐만 아니라 전문 해석 분야까지 CATIA V5 환경 내에서 완벽하게 통합을 이루어, 설계-해석 두 프로세스간에 피드백이 자연스럽게 이루어지는 등 설계-해석주기(Cycle)를 극소화시킴으로써, 궁극적으로 품질 개선을 이루고 전체 개발기간을 단축시킬 수 있게 한다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2011.11a
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• pp.8-9
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• 2011

본 논문에서는 수상 및 수중운동체의 안정성 및 안정화기법에 관해 고찰한다. 선박이 운동을 하게 되면 부가질량이 변하게 되고 대칭인 시스템행렬이 비대칭이 된다. 비대칭성에 따라 시스템의 안정성해석방법도 달라지는데 예를 들어 가속도 피드백을 통해 비대칭요소를 제거하여 대칭으로 변환시키는 것이 가장 대표적인 해석 및 안정화 기법이다. 시스템 모델자체는 어디까지나 모델이기 때문에 대상시스템을 명확하게 수식으로 표현할 수 없으므로 피드백에 의한 비대칭요소를 소거시키는 방법은 타당하지 못하다. 따라서 본 논문에서는 대칭행렬이 비대칭행렬로 변하는 제약에 구애받지 않는, 보다 일반성을 갖는 안정성해석법을 제안한다.

• The Journal of the Korea Contents Association
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• v.17 no.2
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• pp.687-695
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• 2017

This study tried to confirm the effective intervention to reduce drinking frequency and problem behaviors among the three interventions; school based, feedback, and behavior change. Meta-analysis was conducted targeting at 16 studies of randomized controlled trial in which alcohol intervention has been applied to adolescent. The drinking frequency and problem behaviors were analyzed by follow up period. There was a significant difference in the feedback intervention to reduce the frequency of drinking under 3 months of follow up period. Also, there was a significant difference in the feedback intervention to reduce the problematic behaviors of drinking between 4 and 12 months of follow up period(p<.05). The study confirmed that feedback intervention is effective in reducing the frequency of drinking during the follow up period under 3 months, and it is effective in reducing the problem behaviors of drinking during the 4~12 months of follow up period. Also, the study confirmed that school-based intervention and feedback intervention were useful in reducing and preventing harmful effects of drinking by adolescents.

• Journal of the Korean Institute of Intelligent Systems
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• v.13 no.5
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• pp.582-589
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• 2003

This paper presents the robust stability analysis and design methodology of the fuzzy feedback linearization control systems. Uncertainty and disturbances with known bounds are assumed to be included Un the Takagi-Sugeno (TS) fuzzy models representing the nonlinear plants. $L_2$ robust stability of the closed system is analyzed by casting the systems into the diagonal norm bounded linear differential inclusions (DNLDI) formulation. Based on the linear matrix inequality (LMI) optimization programming, a numerical method for finding the maximum stable ranges of the fuzzy feedback linearization control gains is also proposed. To verify the effectiveness of the proposed scheme, the robust stability analysis and control design examples are given.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.231-231
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• 2004

공학해석기반의 설계/제조 시스템에서의 설계는 설계평가와 설계 trade-offs로 구성되어 진다. 설계평가는 설계의 유용성을 평가하거나 CAD모델을 공학해석 모델로 변환하여 구조해석을 통하여 평가하기 위해 사용되며 이러한 평가결과를 근거로 성능치를 정의하고 CAD모델에서의 치수가 trade-offs 해석을 위한 설계변수로 정의되어 진다. 설길 trade-offs는 개선된 설계를 얻기 위한 목적으로 수행되는 데 설계변경은 CAD와 공학해석 모델로 피드백하게 된다.(중략)

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.5
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• pp.1399-1406
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• 2008

This study has been made to research effect of neurofeedback training on the Brain Quotient and baduk strength whose EEC data were obtained both before and after the neurofeedback training from 15th June, to 15th September in 2007. Brain waves were measured on the frontal lobes of subjects (30 baduk players - the experimental group 15 under neuroffedback training and the control group 15 subjects) and analyzed by calculating eight brain quotients characterizing behaviors of EEG rhythms effectively. The results of the analysis show that the experimental group has the higher indexes Attention Quotient(left) p=.041, (right)p=.007, Stress Quotient (left) p=.020, and Stress Quotient (right) p=.019 show statistically significant difference between two groups. The research data show that the experimental group have the higher average than the control group in Baduk strength examination p=.021 after the neuroffedback training. As the brain waves are adjusted by timeseries linear analysis, the brain function quotients can reflect the functional states of the brain.

• The Transactions of the Korean Institute of Power Electronics
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• v.3 no.1
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• pp.77-84
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• 1998

This paper describes a control system design for the transmission STATCOM by applying a no-linear state feedback, and the performance analysis of the control system by simulations and scaled-model experiments. A mathematical model for the STATCOM was derived using a 3-phase equivalent circuit and a perturbation state equation with respect to a typical operating point. A transfer function to describe the dynamics of STATCOM was derived by considering nonlinear state feedback. A controller design was completed by analyzing the feedback system stability with root locus method. The performance analysis of the conceived control system was verified by simulations with the EMTP and experiments with scaled model, assuming that the STATCOM is connected to an 154kV transmission system. The results show that the conceived control system has excellent performance to control the reactive power of the transmission system.

• Journal of the Korea Convergence Society
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• v.8 no.4
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• pp.111-122
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• 2017

The purpose of this study was to develop a computer-based cognitive bias modification program (CBM-I) and to test the efficacy of CBM-I for college students with social anxiety. Forty socially anxious individuals were randomly assigned to the CBM-I(n=21) or a waiting list condition(n=19). Both groups were assessed at the beginning and the end of the program with interpretation bias and social anxiety symptoms(e.g. B=FNE=Brief-Fear of Negative Evaluation Scale, LSAS=Liebowitz Social Anxiety Scale). The CBM-I modified interpretation by providing positive feedback when participants made benign interpretations and negative feedback in response to threat interpretations. Participants in CBM-I completed three computer sessions over three weeks. The CBM-I successfully decreased social anxiety symptoms compared to the control condition(t=2.35, p<.05; t=4.70, p<.001). This result suggests that interpretation modification may have clinical utility when applied as a multi-session intervention.

• Journal of the Earthquake Engineering Society of Korea
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• v.2 no.4
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• pp.95-102
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• 1998

본 연구의 목적은 능동질량 장치를 이용하여 지진하중을 받는 건물모델의 응답을 제어하는 것으로서 실험에 사용된 능동질량 장치는 교류형 서보 모터에 의해 관성력이 건물모델의 응답에 반작용하여 제어를 하게 되는 원리를 이용한 것이다 소형 진동대에 의한 외부하중 묘사 신호처리와 제어력 발생을 위한 장비들이 구축된 실험 모델로써 능동 질량 추진기가 1층 전단형 건물모델 상부에 설치된 해석 모델을 실현하였으며 제어력 산정을 위한 선형 2차 제어 알고리듬은 LabVIEW 프로그램을 사용해서 구현하였다. 건물의 응답과 제어력을 고려해서 제어성능을 검증하였으며 능동 질량 장치를 설치함으러써 공진하중과 지진하중에 대한 건물의 응답이 감소하고 또한 속도피드백 알고리듬이 그 외의 피드백 알고리듬 보다 제어력이 가장 적게 소용되면서 건물의 응답을 감소시키는 것을 실험적으로 파악하였다.