• Journal of Advanced Marine Engineering and Technology
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• v.27 no.6
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• pp.767-775
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• 2003

This paper considers the method of elimination harmonics in AC/DC converters, There are few practical methods to reduce the harmonics in AC/DC converters, particularly in filter design and control strategy. In this paper, a harmonic elimination methods are proposed, which includes hybrid PWM control strategy. These methods achieve precise output control along with the optimum performance simultaneously. The control method in this paper is developed to eliminate a fixed number of harmonics in AC to DC converter. The higher order harmonics can be easily eliminated by using filter proposed in this paper. The validity of these methods is confirmed experimentally.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.24 no.1 s.173
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• pp.240-249
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• 2000

An improved global optimization algorithm is developed by extending the domain elimination method. The concept of triangular patch consists of two or more trajectories of local minimizations is introduced to widen the attraction region of the domain elimination method. Using the an-]c between each of three vertices of the patch and a design point, we measure the proximity, between the design point and the patch. With the Gram-Schimidt orthonormalization, this method can be extended to general n-dimensional problems. We code the original domain elimination algorithm and a patch-based algorithm. Then we compare the performance of two algorithms. Through the well-known example problems. the algorithm using patch is shown to be superior to the original domain elimination algorithm in view of computational efficiency.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.613-615
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• 1996

Harmonic elimination method of using coupling transformer in twelve pulse inverter is presented for high power application. This method is using coupling transformer and PWM(pulse width modulation) switching and voltage source inverter. The object of proposed harmonic elimination method is obtained inverter output of low THD(Total Harmonic Distortion). The simulation results confirm the proposed harmonic elimination method.

• Journal of The Korean Society of Clinical Toxicology
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• v.7 no.2
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• pp.150-155
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• 2009

Purpose: Extracorporeal elimination of drugs is a critical part of managing poisonings, although the indications and optimal method remain a matter of debate. The aim of this study is to report our clinical experiences with continuous renal replacement therapy (CRRT), as performed by emergency room physicians, as method of extracorporeal drug elimination in patients with poisoning. Methods: This study was a retrospective study of the consecutive patients who underwent CRRT, as performed by an emergency room physician, for acute poisoning. The patient characteristics, the kinds of drugs and the method of extracorporeal elimination were analyzed by reviewing the patients' charts. Results: During eleven months, 26 patients with acute poisoning underwent extracorporeal elimination (2 patients; intermittent hemodialysis, 24 patients; CRRT). The mean time from the decision to performing extracorporeal elimination was $206.0{\pm}36.8$ minutes for intermittent hemodialysis, $62.9{\pm}8.5$ minutes for continuous venoveno-hemodiafiltration (CVVHDF) and $56.6{\pm}6.8$ minutes for charcoal hemoperfusion. For the patients with CRRT, CVVHDF was conducted in 10 patients (3 patients; valproic acid, 2 patients; Lithium, 1 patient; salicylates, 1 patient; methanol) and charcoal hemoperfusion by using CRRT was done in 14 patients (13 patients; paraquat, 1 patient; dapsone). For the 12 patients who required hemodialysis due to severe poisoning, 7 patients underwent CRRT because of their unstable vital signs. Conclusion: CRRT was an effective method of extracorporeal drug elimination in patients with acute poisoning, and especially for the cases with unstable vital sign and for those patients who required an early start of extracorporeal elimination according to the characteristics of the drug. (ED note: the writing of the abstract was not clear. Check it carefully.)

• Proceedings of the Korea Association of Information Systems Conference
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• 2002.11a
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• pp.289-312
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• 2002

This study suggests the Link weight analysis approach to choose input variables and an integrated model to make more accurate bankruptcy prediction model. the Link weight analysis approach is a method to choose input variables to analyze each input node's link weight which is the absolute value of link weight between an input nodes and a hidden layer. There are the weak-linked neurons elimination method, the strong-linked neurons selection method in the link weight analysis approach. The Integrated Model is a combined type adapting Bagging method that uses the average value of the four models, the optimal weak-linked-neurons elimination method, optimal strong-linked neurons selection method, decision-making tree model, and MDA. As a result, the methods suggested in this study - the optimal strong-linked neurons selection method, the optimal weak-linked neurons elimination method, and the integrated model - show much higher accuracy than MDA and decision making tree model. Especially the integrated model shows much higher accuracy than MDA and decision making tree model and shows slightly higher accuracy than the optimal weak-linked neurons elimination method and the optimal strong-linked neurons selection method.

• Journal of Ginseng Research
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• v.44 no.6
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• pp.784-789
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• 2020

Background: The separation of isomeric compounds from a mixture is a recurring problem in chemistry and phytochemistry research. The purification of pharmacologically active ginsenoside Rb₃ from ginseng extracts is limited by the co-existence of its isomer Rb₂. The aim of the present study was to develop an enzymatic elimination-combined purification method to obtain pure Rb₃ from a mixture of isomers. Methods: To isolate Rb₃ from the isomeric mixture, a simple enzymatic selective elimination method was used. A ginsenoside-transforming glycoside hydrolase (Bgp2) was employed to selectively hydrolyze Rb₂ into ginsenoside Rd. Ginsenoside Rb₃ was then efficiently separated from the mixture using a traditional chromatographic method. Results: Chromatographic purification of Rb₃ was achieved using this novel enzymatic elimination-combined method, with 58.6-times higher yield and 13.1% less time than those of the traditional chromatographic method, with a lower minimum column length for purification. The novelty of this study was the use of a recombinant glycosidase for the selective elimination of the isomer. The isolated ginsenoside Rb₃ can be used in further pharmaceutical studies. Conclusions: Herein, we demonstrated a novel enzymatic elimination-combined purification method for the chromatographic purification of ginsenoside Rb₃. This method can also be applied to purify other isomeric glycoconjugates in mixtures.

• Journal of Korean Institute of Industrial Engineers
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• v.29 no.1
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• pp.78-89
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• 2003

Ordering is performed to reduce the amount of fill-ins of the Cholesky factor of a symmetric positive definite matrix. This paper proposes a new ordering algorithm that reduces the fill-ins of the Cholesky factor iteratively by elimination tree rotations and clique separators. Elimination tree rotations have been used mainly to reorder the rows of the permuted matrix for the efficiency of storage space management or parallel processing, etc. In the proposed algorithm, however, they are repeatedly performed to reduce the fill-ins of the Cholesky factor. In addition, we presents a simple method for finding a minimal node separator between arbitrary two nodes of a chordal graph. The proposed reordering procedure using clique separators enables us to obtain another order of rows of which the number of till-ins decreases strictly.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.56 no.7
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• pp.1331-1338
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• 2007

A new method for detecting and eliminating the Electrocardiogram(ECG) artifact from the scalp Electroencephalogram(EEG) is proposed. Based on the single channel EEG, the proposed method consists of 4 procedures: emphasizing the R-wave of ECG artifact from EEG using the least squares acceleration(LSA) filter, detecting the R-wave from the LSA filtered EEG using the phase space method and R-R interval, generating the delayed impulse synchronized to the R-wave and elimination of the ECG artifacts based on the adaptive digital filter using the impulse and raw EEG. The performance of the proposed method was evaluated in the two separating parts of R-wave detection and, ECG estimation and elimination from EEG. In the R-wave detection, the proposed method showed the mean error rate of 6.285(%). In the ECG estimation and elimination using simulated and/or real EEG recordings, we found that the ECG artifacts were successfully estimated and eliminated in comparison with the conventional multi-channel techniques, in which independent component analysis and ensemble average method are used. From this we can conclude that the proposed method is useful for the detecting and eliminating the ECG artifact from single channel EEG and simple for ambulatory/portable EEG monitoring system.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.43 no.2
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• pp.189-196
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• 1994

This paper describes a parallel computing algorithm in Gauss elimination of Jacobian matrix to large-scale power system. The structure of Jacobian matrix becomes different according to ordering method of buses. In sequential computation buses are ordered to minimize the number of fill-in in the triangulation of the Jacobian matrix. The proposed method develops the parallelism in the Gauss elimination by using ND(nested dissection) ordering. In this procedure the level structure of the power system network is transformed to be long and narrow by using end buses which results in balance of computing load among processes and maximization of parallel computation. Each processor uses the sequential computation method to preserve the sqarsity of matrix.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.45 no.9
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• pp.65-70
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• 2008

In FIR filter design, multipliers occupy most of the area. To efficiently reduce the area occupied by multipliers, Common Subexpression Elimination (CSE) algorithm can be used instead of separate multipliers. However, the filter computation time can be increased due to the long carry propagation in CSE circuits. More specifically, when the difference of weights between the two inputs to an adder in CSE circuits is large, long carry propagation time is required due to large sign extension. In this paper, we propose a sign-extension reduction method in common subexpression elimination circuit. By Synopsys simulation using Samsung 0.35um library, it is shown that the proposed method leads to 17%, 31% and 12% reduction in the area, time delay and power consumption, respectively, compared with conventional method.