• Title/Summary/Keyword: alternating method

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ALTERNATING RESOLVENT ALGORITHMS FOR FINDING A COMMON ZERO OF TWO ACCRETIVE OPERATORS IN BANACH SPACES

  • Kim, Jong Kyu;Truong, Minh Tuyen
    • Journal of the Korean Mathematical Society
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    • v.54 no.6
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    • pp.1905-1926
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    • 2017
  • In this paper we introduce a new iterative method by the combination of the prox-Tikhonov regularization and the alternating resolvents for finding a common zero of two accretive operators in Banach spaces. And we will give some applications and numerical examples. The results of this paper improve and extend the corresponding results announced by many others.

Fabrication of YBCO Superconducting Thick Film by Use of Lateral Shaky Field Assisted EPD Method (측면진동보조전계 전기영동 전착방식을 적용한 YBCO 초전도 후막의 제작)

  • 소대화;전용우
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.16 no.11
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    • pp.1041-1046
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    • 2003
  • In order to improve the surface uniformity and the conduction properties of the fabricated YBCO thick films, a system that applies alternating field vertically to the EPD field has been developed for the first time and applied to the electrophoretic deposition process. The applied alternating electric field, so called Shaky Alternating Assisted Field, caused a force to be exerted on each YBCO particle and resulted in a shaking of the particle in the direction of applied electric field, accomplishing a uniform particle orientation. The usual commercial electrical power was used for the vertically applied alternating voltage and the induced electric field was 25-120 V/cm at 60Hz. The thick film fabricated by the method developed in this paper showed better surface uniformity without crack and porosity and improved film characteristics such as critical temperature (Tc,zero = 90 K) and critical current density (2354 A/$\textrm{cm}^2$), Therefore, it is expected that the shaky-aligned electrophoretic deposition method can be used to fabricate superconductor films through a simpler process and at less expense.

Frequency Response Characteristics of Fluorescent OLED with Alternating Current Driving Method (교류구동방식에 의한 형광 OLED의 주파수 응답 특성)

  • Seo, Jung-Hyun;Ju, Sung-Hoo
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.32 no.1
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    • pp.40-46
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    • 2019
  • To study the frequency response characteristics of alternating-current-driven organic light-emitting diodes (OLEDs), we fabricated blue-fluorescent OLEDs and analyzed their electroluminescent characteristics according to the alternating current voltage and frequency. The luminance-frequency characteristics of alternating-current-driven OLED was similar to that of a low-pass filter, and the luminance of high-voltage OLED decreased at higher frequency than low-voltage OLED. The luminance characteristics of the OLED according to the frequency is due to the capacitive reactance in the OLED, generated during the alternating current driving. The frequency response characteristics of the OLED according to the voltage is due to the decrease in internal resistance of the organic layer. In addition, the negative voltage component of the alternating current did not affect the frequency response of the OLED. Therefore, the electroluminescent characteristics of OLED with an alternating current power of 60 Hz are not influenced by the frequency.

Examination and Improvement of Accuracy of Three-Dimensional Elastic Crack Solutions Obtained Using Finite Element Alternating Method (유한요소 교호법으로 구한 삼차원 균열 탄성해의 정확성 향상 및 검토)

  • Park, Jai-Hak;Nikishkov, G.P.
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.5
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    • pp.629-635
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    • 2010
  • An SGBEM (symmetric Galerkin boundary element method)-FEM alternating method has been proposed by Nikishkov, Park and Atluri. This method can be used to obtain mixed-mode stress intensity factors for planar and nonplanar three-dimensional cracks having an arbitrary shape. For field applications, however, it is necessary to verify the accuracy and consistency of this method. Therefore, in this study, we investigate the effects of several factors on the accuracy of the stress intensity factors obtained using the abovementioned alternating method. The obtained stress intensity factors are compared with the known values provided in handbooks, especially in the case of internal and external circumferential semi-elliptical surface cracks. The results show that the SGBEM-FEM alternating method yields accurate stress intensity factors for three-dimensional cracks, including internal and external circumferential surface cracks and that the method can be used as a robust crack analysis tool for solving field problems.

An Efficient Implementation of Optimal Power Flow using the Alternating Direction Method (Alternating Direction Method를 이용한 최적조류계산의 분산처리)

  • Kim, Ho-Woong;Park, Marn-Kuen;Kim, Bal-Ho
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.48 no.11
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    • pp.1424-1428
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    • 1999
  • This paper presents a mathematical decomposition coordination method to implementing the distributed optimal power flow (OPF), wherein a regional decomposition technique is adopted to parallelize the OPT. The proposed approach is based on the Alternating Direction Method (ADM), a variant of the conventional Augmented Lagrangian approach, and makes it possible the independent regional AC-OPF for each control area while the global optimum for the entire system is assured. This paper is an extension of our previous work based on the auxiliary problem principle (APP). The proposed approach in this paper is a completely new one, however, in that ADM is based on the Proximal Point Algorithm which has long been recognized as one of the attractive methods for convex programming and min-max-convex-concave programming. The proposed method was demonstrated with IEEE 50-Bus system.

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Analysis of an Isotropic Infinite Plate with Many Collinear Multiple Cracks by the Alternating Method (다수의 직선 다중균열이 존재하는 등방성 무한판의 교호법을 이용한 해석)

  • Park, Jai-Hak
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.20 no.12
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    • pp.3838-3846
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    • 1996
  • A method is proposed to obtain the stress intensity factors of multiple cracks lying on many straight llnes in an infinite isotropic plate. In this mehtod, analytical solutions for collinear multiple cracks subject to surface point forces are obrained and used as Green functions. For the multiple cracks lying onmany straight lines, the equivalent crack surface tractions are obtained by using the alternating method and the stress intensity factors are calculated. By using the proposed method several useful problems are solved and discussed.

TWO-LAYER MUTI-PARAMETERIZED SCHWARZ ALTERNATING METHOD FOR TWO-DIMENSIONAL PROBLEMS

  • Kim, Sang-Bae
    • Journal of applied mathematics & informatics
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    • v.30 no.3_4
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    • pp.477-488
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    • 2012
  • The convergence rate of a numerical procedure based on Schwarz Alternating Method(SAM) for solving elliptic boundary value problems depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It has been observed that the mixed interface condition, controlled by a parameter, can optimize SAM's convergence rate. In [8], one introduced the two-layer multi-parameterized SAM and determined the optimal values of the multi-parameters to produce the best convergence rate for one-dimensional elliptic boundary value problems. In this paper, we present a method which utilizes the one-dimensional result to get the optimal convergence rate for the two-dimensional problem.

TWO-DIMENSIONAL MUTI-PARAMETERIZED SCHWARZ ALTERNATING METHOD

  • Kim, Sang-Bae
    • Journal of applied mathematics & informatics
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    • v.29 no.1_2
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    • pp.161-171
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    • 2011
  • The convergence rate of a numerical procedure based on Schwarz Alternating Method(SAM) for solving elliptic boundary value problems depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It has been observed that the Robin condition (mixed interface condition), controlled by a parameter, can optimize SAM's convergence rate. In [7], one had formulated the multi-parameterized SAM and determined the optimal values of the multi-parameters to produce the best convergence rate for one-dimensional elliptic boundary value problems. However it was not successful for two-dimensional problem. In this paper, we present a new method which utilizes the one-dimensional result to get the optimal convergence rate for the two-dimensional problem.

The Three-Dimensional Partial Differential Equation with Constant Coefficients of Time-Delay of Alternating Direction Implicit Format

  • Chu, QianQian;Jin, Yuanfeng
    • Journal of Information Processing Systems
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    • v.14 no.5
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    • pp.1068-1074
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    • 2018
  • In this paper, we consider the delay partial differential equation of three dimensions with constant coefficients. We established the alternating direction difference scheme by the standard finite difference method, gave the order of convergence of the format and the expression of the difference scheme truncation errors.

TWO-LAYER MULTI-PARAMETERIZED SCHWARZ ALTERNATING METHOD FOR 3D-PROBLEM

  • KIM, SANG-BAE
    • Journal of applied mathematics & informatics
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    • v.34 no.5_6
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    • pp.383-395
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    • 2016
  • The convergence rate of a numerical procedure based on Schwarz Alternating Method (SAM) for solving elliptic boundary value problems depends on the selection of the interface conditions applied on the interior boundaries of the overlapping subdomains. It has been observed that the Robin condition (mixed interface condition), controlled by a parameter, can optimize SAM's convergence rate. In [8], one formulated the twolayer multi-parameterized SAM and determined the optimal values of the multi-parameters to produce the best convergence rate for one-dimensional elliptic boundary value problems. Two-dimensional implementation was presented in [10]. In this paper, we present an implementation for threedimensional problem.