• Proceedings of the KIEE Conference
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• 2004.07d
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• pp.2546-2549
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• 2004

For Reduction of Power-Loss, a new Lateral Information Propagation Networks(LIPN) has been proposed. Damaged insulator is reduced the rate of insulation extremely, and taken the results dirty and injured. It is necessary to be actions that detect the damaged insulator and exchange the new one. And thus, we have designed the LIPN to be detected that insulators by the real time computation method through the inter-node diffusion. In the network, a node corresponds to a state in the quantized input space. Each node is composed of a processing unit and fixed weights from its neighbor nodes as well as its input terminal. Information propagates among neighbor nodes laterally and inter-node interrelation is achieved. Through the results of simulation experiments, we difine the ability of real-time detecting the damaged insulators.

• Journal of Institute of Control, Robotics and Systems
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• v.4 no.4
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• pp.413-419
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• 1998

A novel order-reduction technique for model predictive control(MPC) is proposed based on the singular value decomposition(SVD) of a pulse response circulant matrix(PRCM) of a concerned system. It is first investigated that the PRCM (in the limit) contains a complete information of the frequency response of a system and its SVD decomposes the information into the respective principal directions at each frequency. This enables us to isolate the significant modes of the system and to devise the proposed order-reduction technique. Though the primary purpose of the proposed technique is to diminish the required computation in MPC, the clear frequency decomposition of the SVD of the PRCM also enables us to improve the robustness through selective excitation of frequency modes. Performance of the proposed technique is illustrated through two numerical examples.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.556-558
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• 1990

A method of model reduction for reducing a higher order Z-transfer function to its lower order model is developed based on the Block - pulse function. The approach is following : I. Block - pulse function can be applied for Z-transfer function of linear digital system described by high order. II. To determined both the coefficients of the denominator and numerator of reduced model. The proposed method is simple for computation, can preserve the dynamic characteristic of the original model satisfactorily.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.27 no.2
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• pp.276-284
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• 2003

The preconditioned conjugate gradient method is an efficient iterative solution scheme for large size finite element problems. As preconditioning method, we choose an incomplete Cholesky factorization which has efficiency and easiness in implementation in this paper. The incomplete Cholesky factorization mettled sometimes leads to breakdown of the computational procedure that means pivots in the matrix become minus during factorization. So, it is inevitable that a reduction process fur stabilizing and this process will guarantee robustness of the algorithm at the cost of a little computation. Recently incomplete factorization that enhances robustness through increasing diagonal dominancy instead of reduction process has been developed. This method has better efficiency for the problem that has rotational degree of freedom but is sensitive to parameters and the breakdown can be occurred occasionally. Therefore, this paper presents new method that guarantees robustness for this method. Numerical experiment shows that the present method guarantees robustness without further efficiency loss.

• Journal of the Korea Society of Computer and Information
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• v.4 no.4
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• pp.25-33
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• 1999

Exchanging parametric curves and surfaces between different geometric modeling systems often require degree reductions to approximate the curves and surfaces to the degree of supporting systems within the given tolerance. This paper is a research for approximate conversion of a degree reduction methods for Bezier curves in the data exchange between the different systems. Our approximate conversion is implemented that shows the experimental results with the others to reduce the degree from the given degree n to n-1 for the Bezier curves about the different degree reductions.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.31 no.11
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• pp.133-140
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• 1982

In recent years, a number of thyristor-controlled shunt compensators have been used in industrial and utility systems for phase balancing, power-factor correction and flicker reduction. This paper describes a simple and basic control scheme and circuits for shunt compensator with a fixed capacitor and thyristor-controlled reactor. Feedforward-control scheme is applied, and compensating currents are computed from the symmetrical components of the disturbed system. A 8 bit microprocessor is used for the computation of the compensating currents as well as for the measurements of the symmetric components. A 3-phase 1 KVA compensator is developed and a good reduction of the unbalance factor of the power source is achieved using it.

• Proceedings of the KIEE Conference
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• 1998.11a
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• pp.335-337
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• 1998

This paper presents a efficient algorithm for loss reduction of distribution system by automatic sectionalizing switch operation in distribution systems of radial type. Simulated Annealing can avoid escape from local minima by accepting improvements in cost, but the use of this algorithm is also responsible for an excessive computation time requirement. To overcome this major limitation of Simulated Annealing Algorithm, we may use advanced Simulated Annealing Algorithm. Numerical examples demonstrate the validity and effectiveness of the proposed methodology.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.1104-1111
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• 1994

Code Excited Linear Prediction(CELP) as a speech coder exhibits good performance at data rates below 4.8 kbps. The major drawback to CELP type coders is their large amount of computation. In this paper, we propose a new pitch search method that preserves the quality of the CELP vocoder with reduced complexity. The basic idea is to restrict the pitch searching range by estimating the preliminary pitches. Applying the proposed method to the CELP vocoder, we can get approximately 87% complexity reduction in the pitch search.

• Proceedings of the Acoustical Society of Korea Conference
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• 1994.06a
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• pp.904-911
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• 1994

Code Excited Linear Prediction (CELP) speech coders exhibit good performance at data rates below 4.8 kbps. The major drawback to CELP type coders is their many computation. In this paper, we propose a new pitch search method that preserves the quality of the CELP vocoder with reducing complexity. The basic idea is to apply the preprocessing technique beforehand grasping the autocorrelation property of speech waveform. By using the proposed method, we can get approximately 77% complexity reduction in the pitch search.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1999.10a
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• pp.244-250
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• 1999

Active vibration control method for the reduction of vibration of structures have been developed. For the application of real structures active control system that has robustness must be designed because the mathematical model incompletely described has intrinsically modeling error. In this research we propose LQG/LTR method in designing control system with robustness. A combination of acceleration feedback and model-order reduction technique is used for the application of real structures and the computation efficiency. In case of such structures as the building and the tower the inter-story relative displacements represent an important constraint in seismic design. Therefore selection method of design parameters is also proposed in order to reduce the inter-story relative displacements.