• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.85-88
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• 1996

We develop an efficient technique of controlling chaos using M-step ahead prediction with the OGY method. It has smaller transient time than the OGY method, and prevents burst phenomena that occur in noisy environment. This technique is very simple and needs small memory compared with targeting algorithms. Numerical examples show that the proposed algorithm has good performance, especially in noisy environment.

• 한국정보전자통신기술학회논문지
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• 제9권5호
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• pp.445-450
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• 2016

In this paper we study the effect of chaos in nonuniform instability with optical fiber based IoT networks. The transient response of optically controlled fiber has also described. Nonlinear optical fiber effects especially fiber scattering in networks has emerged as the essential means active optical devices. The paradigm instability in fiber Internet serves as a test for fundamental study of chaos and its suppression and exploitation in practical application in optical communication. This paper attempts to present a survey and some of our research findings on the nature of chaotic effect on Internet based optical communication. The transient response in optical fiber has been evaluated theoretically by calculating the variation of the scattering function. The lines has used under open ended termination containing optically induced region. The scattered optical waves in a fiber used in optic communications are temporally unstable above certain threshold intensity.

• 대한전기학회논문지:전력기술부문A
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• 제48권12호
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• pp.1486-1491
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• 1999

This paper presents a method of recognizing high impedance fault(HIF) of electrical power systems and classifying fault patterns based on chaos attractors. Two dimensional chaos attractors are reconstructed from neutral point current waveforms. Reliable features for HIF pattern classification are obtained from the chaos attractors. Radial basis function network, trained with two types of HIF data generated by the electromagnetic transient program and measured form actual faults. The RBFN successfully classifies normal and the three types of fault patterns according to the features generated from the chaos attractors.

• 대한전기학회논문지:전력기술부문A
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• 제48권3호
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• pp.197-202
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• 1999

Electric arc furnaces (EAFs) use bulk electrical energy to create heat in metal refining industries. The electric arc process is a main cause of the degradation of the electric power quality such as voltage flicker due to the interaction of the high demand currents of the load with the supply system impedance. The stochastic models have described the aperiodic physical phenomena of EAFs. An alternative approach is to include deterministic chaos in the characterization of the arc currents. In this parer, a chaotic approach to such modeling is described and justified. At the same time, a DLL(Dynamic Link Library) module, which is a FORTRAN interface with TACS (Transient Analysis of Control Systems), is developed to implement the chaotic load model in the Electromagnetic Transients Program (EMTP). The details of the module and the results of tests performed on the module to verify the model and to illustrate its capabilities are presented in this paper.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2004년도 추계학술대회 논문집 전기물성,응용부문
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• pp.141-143
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• 2004

In this present the transient control of SBS chaos induced instability in Brillouin-active fiber systems is described. The inherent optical feedback by the backscattered Stokes wave in optical fiber systems leads to instabilities in the form of optical chaos. At weak power, the nature of the Brillouin instability can occur at before threshold. At strong power, the temporal evolution above threshold is periodic and at higher intensity can become chaotic. Multistable periodic states, makes transition to logic 'on' or 'off'. It can make theoretically potential large memory capacity.

• 융합신호처리학회논문지
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• 제5권1호
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• pp.32-39
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• 2004

생체 뉴론은 일반적으로 지속적 또는 과도적인 카오틱 특성을 가지고 있다. 생체 뉴론의 카오틱 반응에 대한 분석적인 해석은 아직까지 이루어지지 않고 있다. 동적 카오틱 반응에 대한 카오틱 뉴런의 과도 카오틱 특성은 지역 수렴 문제를 극복하는데 도움이 되지만 일반적으로 지속적인 카오틱 응답은 최적화 문제에 악영향을 미치게 되므로 초기 카오틱 특성은 사라져야 한다. 패턴 인식, 확인, 예측, 그리고 제어에 사용되는 대부분의 신경회로망 응용에 있어서 필요한 최적화 문제를 해결하기 위해서는 뉴론은 한 개의 안정적인 고정점을 가지고 있어야 한다. 본 논문에서는 동적 카오틱 뉴런의 동적 특성과 카오틱 응답을 발생시키는 조건을 분석하고, 카오틱 뉴런의 수렴조건을 제안하였다.

• International Journal of Fuzzy Logic and Intelligent Systems
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• 제7권4호
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• pp.242-248
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• 2007

This paper analyzes on the chaos characteristics of the chaotic neural networks and presents the convergence condition. Although the transient chaos of neural network sould be beneficial to overcome the local minimum problem and speed up the learning, the permanent chaotic response gives adverse effect on optimization problems and makes neural network unstable in general. This paper investigates the dynamic characteristics of the chaotic neural networks with the chaotic dynamic neuron, and presents the convergence condition for stabilizing the chaotic neural networks.

• Journal of Electrical Engineering and Technology
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• 제1권4호
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• pp.546-549
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• 2006

In this paper the neuron operation based on Brillouin-active fiber in optical fiber is described. The inherent optical feedback by the backscattered stokes wave in optical fiber leads to instabilities in the form of optical chaos. Controlling of chaos induced transient instability in Brillouin-active fiber is implemented with Kerr nonlinearity having a non-instantaneous response in network systems. The controlling chaotic instabilities can lead to multistable periodic states; create optical logic 'on' or high level '1' or 'off', or low level '0'. It is theoretically possible to apply the multi-stability regimes as an optical memory device for encoding and decoding series and complex data transmission in optical systems.

• Steel and Composite Structures
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• 제22권6호
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• pp.1261-1280
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• 2016

We study chaotic motion in a nonlinear laminated composite plate under subsonic fluid flow and a simultaneous external load in this paper. We derive equations of motion of the plate using the von-$K{\acute{a}}rm{\acute{a}}n^{\prime}s$ hypothesis and the Hamilton's principle. Galerkin's approach is adopted as the solution method. We then conduct a divergence analysis to obtain critical velocities of the transient flow. Melnikov's integral approach is used to find the critical parameters in which chaos takes place. Effects of different parameters including the aspect ratio, plate material and the ply angle in laminates on the critical flow speed are investigated. In a parametric study, we show that how the linear and nonlinear stiffness of the plate and the load frequency and amplitude would influence the chaotic behavior of the plate.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2272-2274
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• 1998

This paper presents recognition and classification of high impedance fault(HIF) patterns in the electrical power systems based on chaotic features. Chaotic features are obtained from two dimensional chaos attractors reconstructed from fault current waveform. The RBFN is trained with the two types of HIF data generated by the electromagnetic transient program and measured from actual faults. The RBFN successfully classifies normal and the three types of fault patterns based on the binary chaotic features.