• Journal of Power Electronics
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• v.15 no.4
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• pp.964-973
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• 2015

This paper presents a simple approach for the selective harmonic elimination (SHE) of multilevel inverter based on the transistor-clamped H-bridge (TCHB) family. The SHE modulation is derived from the sinusoidal voltage-angle equal criteria corresponding to the optimized switching angles. The switching angles are computed offline by solving transcendental non-linear equations characterizing the harmonic contents using the Newton-Raphson method to produce an optimum stepped output. Simulation and experimental tests are conducted for verification of the analytical solutions. An Altera DE2 field-programmable gate array (FPGA) board is used as the digital controller device in order to verify the proposed SHE modulation in real-time applications. An analysis of the voltage total harmonic distortion (THD) has been obtained for multiple output voltage cases. In terms of the THD, the results showed that the higher the number of output levels, the lower the THD due to an increase number of harmonic orders being eliminated.

• Journal of the Institute of Electronics Engineers of Korea SP
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• v.43 no.1 s.307
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• pp.1-8
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• 2006

This paper presents a fast full search algorithm for motion estimation applicable to multiple reference images. The proposed method is an extended version of the rate constrained successive elimination algorithm (RSEA) for multiple reference frame applications. We will show that motion estimation for the reference images temporally preceding the first reference image can be less intensive in computation compared with that for the first reference image. for computational reduction, we will drive a new condition to lead the smaller number of candidate blocks for the best matched block. Simulation results explain that our method reduces computation complexity although it has the same quality as RSEA.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.39 no.3
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• pp.263-272
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• 1990

In the variable speed driving system of a three phase induction motor controlled by a PWM inverter, the output terminal contains considerable amount of harmonic components of the voltage waveform due to the switching action of semiconductor devices, causing torque ripples, acoustic noise and oscillation of the motor. This paper describes a new algorithm which eliminates the harmonics and controls the fundamental voltage in three phase PWM inverter output waveform. The new algorithm utilizes the technique of particular harmonics elimination (PHE) by walsh series in three phase PWM inverter output waveform. A microprocessor (8086 CPU)-controlled three phase induction motor system is described to realize this algorithm. The system is designed for 3 phase output voltage in the 1-60Hz interval where 5th and 7th harmonics, and 5th, 7th, 11th, and 13th harmonics are eliminated. Also, the fundamental wave amplitude is designed to be proportional to the output frequency. The performance of the proposed method shows sufficient elimination of the harmonics and also reduction of computation time which determines switching pattern. The proposed PWM pattern by Walsh series, is effective not only to induction motors but also to other electromagetic equipments such as voltage regulators and UPS.

• Journal of Sensor Science and Technology
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• v.25 no.1
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• pp.13-19
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• 2016

Nowadays, most major automobile manufacturers are very interested, and actively involved, in developing driver alcohol detection system for safety (DADSS) that serves to prevent driving under the influence. DADSS measures the blood alcohol concentration (BAC) from the driver's breath and limits the ignition of the engine of the vehicle if the BAC exceeds the reference value. In this study, to optimize the sensor array of the DADSS, we selected sensors by using three different methods, configured the sensor arrays, and then compared their performance. The Wilks' lambda, stepwise elimination and filter method (using a principal component) were used as the sensor selection methods [2,3]. We compared the performance of the arrays, by using the selectivity and sensitivity as criteria, and Sammon mapping for the analysis of the cluster type of each gas. The sensor array configured by using the stepwise elimination method exhibited the highest sensitivity and selectivity and yielded the best visual result after Sammon mapping.

• Journal of Korean Medical classics
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• v.20 no.3
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• pp.67-77
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• 2007

Through the translation and comparative study of the enriching blood and nourishing vital essence(補陰血方劑) in "The Elimination & Supplement about the Famous Prescription Comments(刪補名醫方論)" of "The Golden Mirror of Medicine(醫宗金鑑)" with "The Famous Prescription Comments on Ancient and Modern Times(古今名醫方論)", we confirmed that about 50% of the sentences from "The Elimination & Supplement about the Famous Prescription Comments(刪補名醫方論)" were quoted in "The Famous Prescription Comments on Ancient and Modern Times(古今名醫方論)", and that many of the text were not quoted unchanged, but were revised and supplemented. In organization, the prescription with the fewer number of component drugs is given first, followed by that with more component drugs, and that with similar component drugs is explained subsequently to facilitate understanding. In the prescription notes, it is emphasized that when enriching blood, the invigorative method(補氣法) is very important and that cold or pungent herb should be very carefully used.

• Journal of IKEEE
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• v.28 no.3
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• pp.432-439
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• 2024

This paper introduces an enhanced Selective Harmonic Elimination (SHE) technique of a single-phase Cascaded H-Bridge (CHB) Multilevel Inverter (MLI) for improving the reliability and power quality of a second life battery energy storage system (ESS). The technique involves solving non-linear transcendental equations derived from Fourier series offline to determine the optimal switching angles for the proposed SHE-PWM implementation. These angles are then applied in real-time via a Look-Up Table (LUT). The Levenberg-Marquardt algorithm, an iterative method, is employed in MATLAB to solve the equations and obtain the switching angles. The effectiveness of the proposed method is validated using PLECS simulation software and is compared with other conventional PWM techniques for MLIs.

• Progress in Superconductivity
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• v.4 no.2
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• pp.114-120
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• 2003

We employed a method eliminating a temporally partial principal component (PC) of multichannel-recorded neuromagnetic fields for excluding spatially correlated noises from event-evoked signals. The noises in magnetoencephalography (MEG) are considered to be mainly spontaneous neuromagnetic fields which are spatially correlated. In conventional MEG experiments, the amplitude of the spontaneous neuromagnetic field is much lager than that of the evoked signal and the synchronized characteristics of the correlated rhythmic noise makes it possible for us to extract the correlation noises from the evoked signal by means of the general PC analysis. However, the whole-time PC of the fields still contains a little projection component of the evoked signal and the elimination of the PC results in the distortion of the evoked signal. Especially, the distortion will not be negligible when the amplitude of the evoked signal is relatively large or when the evoked signals have a spatially-asymmetrical distribution which does not cancel out the corresponding elements of the covariance matrix. In the period of prestimulus, there are only the spontaneous fields and we can find the pure noise PC that is not including the evoked signal. Besides that, we propose a method, called the extended temporal decorrelation method (ETDM), to suppress the distortion of the noise PC from remanent evoked signal components. In this study, we applied the Partial Principal component elimination method (PPCE) and ETDM to simulated signals and the auditory evoked signals that had been obtained with our homemade 37-channel magnetometer-based SQUID system. We demonstrate here that PPCE and ETDM reduce the number of epochs required in averaging to about half of that required in conventional averaging.

• 한국기계연구소 소보
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• s.15
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• pp.19-23
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• 1985

• Proceedings of the Korean Society for Bioinformatics Conference
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• 2005.09a
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• pp.272-277
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• 2005

We introduce a new approach to optimize the parameters in biological kinetic models by quantifier elimination (QE), in combination with numerical simulation methods. The optimization method was applied to a model for the inhibition kinetics of HIV proteinase with ten parameters and nine variables, and attained the goodness of fit to 300 points of observed data with the same magnitude as that obtained by the previous optimization methods, remarkably by using only one or two points of data. Furthermore, the utilization of QE demonstrated the feasibility of the present method for elucidating the behavior of the parameters in the analyzed model. The present symbolic-numeric method is therefore a powerful approach to reveal the fundamental mechanisms of kinetic models, in addition to being a computational engine.

• Journal of the Korean Magnetic Resonance Society
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• v.4 no.2
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• pp.103-115
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• 2000

Wavelet transforms are introduced as a new tool to distinguish real peaks from the noise contaminated NMR data in this paper. New algorithms of two wavelet transforms including Daubechies wavelet transform as a discrete and orthogonal wavelet transform (DWT) and Morlet wavelet transform as a continuous and nonorthogonal wavelet transform(CWT) were developed fer noise elimination. DWT and CWT method were successfully applied to the noise reduction in spectrum. The inevitable distortion of NMR spectral baseline and the imperfection in noise elimination were observed in DWT method while CWT method gives a better baseline ahape and a well noise suppressed spectrum.