• Journal of Advanced Marine Engineering and Technology
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• 제27권6호
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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.

• 대한기계학회논문집A
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• 제24권1호
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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.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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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.

• 대한임상독성학회지
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• 제7권2호
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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.)

• 한국정보시스템학회:학술대회논문집
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• 한국정보시스템학회 2002년도 추계학술대회
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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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• 제44권6호
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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.

• 대한산업공학회지
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• 제29권1호
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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.

• 전기학회논문지
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• 제56권7호
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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.

• 대한전기학회논문지
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• 제43권2호
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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.

• 대한전자공학회논문지SD
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• 제45권9호
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• pp.65-70
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• 2008

FIR 필터에서 곱셈기는 대부분의 면적을 차지한다. FIR 필터의 설계시 개별적인 곱셈기 대신 Common Subexpression Elimination(CSE) 알고리즘을 이용하여 덧셈만으로 곱셈기를 구현할 수 있다. CSE방식은 곱셈을 이용하지 않기 때문에 보다 작은 면적으로 필터를 구현할 수 있으나 덧셈에서 발생하는 캐리의 긴 전파 시간으로 인하여 필터 연산시간이 길어지는 단점이 있다. 특히 더해지는 항의 쉬프트가 클수록 부호 확장이 많아지며 부호확장에 의해 덧셈의 면적이 커지고 계산 시간이 길어진다. 본 논문에서는 CSE 알고리즘에서 부호 확장 부분을 제거하는 방법을 제안하며 제안한 알고리즘을 이용하여 주어진 예제를 삼성 0.35u 공정으로 설계하였을 때 기존 설계 방법 보다 면적, 속도, 파워소모에서 각각 17%, 31%, 12% 의 이득이 있음을 보인다.