• Transactions on Control, Automation and Systems Engineering
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• v.2 no.2
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• pp.85-91
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• 2000

This paper proposes a novel method with pseudo-on-line scheme using the optimized look-up table based on the genetic algorithm which does not use the gradient and finds the global optimum of an un-constraint optimization problem. The technique is a pseudo-on-line method that optimally estimates the parameters of fuzzy PID(FPID) controller for systems with non-linearity, using the genetic algorithm. The proposed controller(GFPID) with the auto-tuning function is applied to the on-line and real-time control of speed at 3-phase induction motor, and its computer simulation is carried out. simulation results show that the proposed methodis more excellent that conventional FPID and PID controllers.

• Journal of Power Electronics
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• v.4 no.3
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• pp.127-137
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• 2004

This paper introduces a hybrid induction motor control using a genetically optimized pseudo-on-line method. Optimization results from the use of a look-up table based on genetic algorithms to find the global optimum of an unconstrained optimization problem. The approach to induction motor control includes a pseudo-on-line procedure that optimally estimates parameters of a fuzzy PID (FPID) controller. The proposed hybrid genetic fuzzy PID (GFPID) controller is applied to speed control of a 3-phase induction motor and its computer simulation is carried out. Simulation results show that the proposed controller performs better than conventional FPID and PID controllers. The contribution of this paper is the introduction of a high performance hybrid form of induction motor control that makes on-line and real-time control of the drive system possible.

• Proceedings of the KIEE Conference
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• 2000.07d
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• pp.2386-2388
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• 2000

This paper proposes a novel method with pseudo-on-line scheme using look-up table based on the genetic algorithm. The technique is a pseudo-on-line method that optimally estimate the parameters of fuzzy PID(FPID) controller for systems with non-linearity using the genetic algorithm which does not use the gradient and finds the global optimum of an un-constraint optimization problem. The proposed controller(GFPID) is applied to speed control of 3-phase induction motor and its computer simulation is carried out. Simulation results show that the proposed method is more excellent than conventional FPID and PID controllers.

• Proceedings of the KIEE Conference
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• 2002.07d
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• pp.2176-2179
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• 2002

This paper introduces a hybrid induction motor control using a genetically optimized pseudo-on-line method. Optimization results from the use of a look-up table based on genetic algorithms to find the global optimum of a un-constraint optimization problem. The approach to induction motor control includes a pseudo-on-line procedure that optimally estimates parameters of a fuzzy PID (FPID) controller. The proposed hybrid genetic fuzzy PID (GFPID) controller is applied to speed control of a 3-phase induction motor and its computer simulation is carried out. Simulation results show that the proposed controller is performs better than conventional FPID and PID controllers. The contribution of this paper is the introduction of a high performance hybrid form of induction motor control that makes on-line and real-time control of the drive system possible.

• Proceedings of the KSMRM Conference
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• 2002.11a
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• pp.76-76
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• 2002

Purpose： The purpose of this study is to optimize the configuration of body RF coil composed of 4 planar subcoils for low field open MRI. Method： Our low field RE coil is composed of 4 subcoils assumed to be located at both the bottom and top sides of permanent magnet. Each subcoils has 3 main strips. The coil system has mirror inversion symmetry. First, the currents on the strips are obtained by inductance calculation and circuit analysis, Second, all the strips are divided into line strip elements across the strips, the self Inductances of line strip elements and the mutual inductances among the line strip elements are calculated, and current distributions of strip are obtained by circuit analysis, where each strip is considered as parallel combination of line strip elements. Finally all the line strip elements are segmented, magnetic field has been calculated by pseudo electric dipole radiation method, where the current elements are regarded as pseudo electric dipole radiation sources. We have performed above procedures for various configurations of RE coil. The field homogeneity is calculated in the 25 cm DSV.

• Journal of the Korean Society for Precision Engineering
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• v.15 no.7
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• pp.91-97
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• 1998

The analysis model is the infinite body consisted of power law creep material containing a rigid inclusion with line crack shape subjected to the arbitrarily directional stress on an infinite boundary. The crack analysis is performed using the complex pseudo-stress function. The strain rate intensity factor is determined in the closed form as new fracture mechanics parmeter which represents the magnitudes of stress and strain rate near the tip in power law creep material.

• Journal of the Korean Institute of Landscape Architecture
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• v.26 no.2
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• pp.28-37
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• 1998

The purpose of this study was to develop a model of plant management based on Robinia pseudo-acacia forests structure in Bucheon city, Korea. For 38 plots were established in Robinia pseudo-acacia forest of Bucheon city. As a result, Robinia pseudo-acacia community was expected to the proceeded to Quercus spp. community. In addition, the diversity of Robinia pseudo-acacia-Quercus spp. community was analyzed higher than Robinia pseudo-acacia community. Based on the result of forest structure analysis, Quercus spp. community was selected as the goal stage of plant management for Bucheon forests and 22 species that were selected by the importance value analysis, classification and ordination analysis and the correlation analysis were chosen as the ecological approprite species. This study also suggested density control guide line for sucession promotion, which individuals numbers of Robinia pseudo-acacia might be reduced from 50 individuals to 23 individuals by selective cutting in order to keep 65% of total basal area.

• The Journal of the Acoustical Society of Korea
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• v.13 no.1E
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• pp.71-81
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• 1994

In this paper, we propose a pseudo-cepstral representation of line spectrum pair(LSP) frequencies and evaluate speech recognition performance with cepstral lift using the pseudo-cepstrum. The pseudo-cepstrum corresponding to LSP frequencies is derived by approxmating the relationship between LPC-cepstrum and LSP frequencies. Three cepstral liftering procedures are applied to the pseudo-cepstrum to improve the performance of speech recognition. They are the root-power-sums ligter, the general exponential lifter, and the bandpass lifter. Then, the liftered psedudo-cepstra are warped into a mel-frequency scale to obtain feature vectors for speech recognition. Among the three lifters, the general exponential lifter results in the best performance on speech recognition. When we use the proposed pseudo-cepstra feature vectors for recognizing noisy speech, the signal-to-noise ratio (SNR) improvement of about 5~10dB LSP is obtained.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.47 no.12
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• pp.31-38
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• 2010

This paper presents the design of a graphic memory for QVGA-scale LCD Driver IC (LDI). The graphic memory is designed based on the pseudo-SHAM for the purpose of small area, and the memory cell structure is designed using a bit line partitioning method to improve sensing characteristics and drivabilties in the line-read operation. Also, a collision protection circuit using C-gate is designed to control collisions between read/write operations and self-refresh/line-read operations effectively. The graphic memory circuit has been designed in transistor level using $0.18{\mu}m$ CMOS technology library and the operations of the graphic memory have been verified using Hspice. The results show that the bit-bitb line voltage difference, ${\Delta}V$ increases by 40%, the charge sharing time between bit and bitb voltages $T_{CHGSH}$ decreases by 30%, and the current during line-read decreases by 40%.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2017.10a
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• pp.674-677
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• 2017

The Hough transform is the most representative algorithm for a straight line detection based on edge pixels. It shows excellent performance in a simple linear image but requires a considerable amount of computation in a noisy or complex image and has a problem of detecting a pseudo straight line easily. In this paper, we propose a straight line detection algorithm to solve the problem of the conventional Hough transform. The proposed algorithm detects the straight line information of edge pixels by using principal component analysis (PCA) before performing Hough transform and performs the Hough transform of the limited slope area in the valid edge pixels based on the detected straight line information of edge pixels. Simulation results show that the proposed algorithm reduces the amount of computation as well as eliminates pseudo straight lines.