• 제목/요약/키워드: Iteration Method

검색결과 1,145건 처리시간 0.033초

Crack analysis of reinforced concrete members with and without crack queuing algorithm

  • Ng, P.L.;Ma, F.J.;Kwan, A.K.H.
    • Structural Engineering and Mechanics
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    • 제70권1호
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    • pp.43-54
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    • 2019
  • Due to various numerical problems, crack analysis of reinforced concrete members using the finite element method is confronting with substantial difficulties, rendering the prediction of crack patterns and crack widths a formidable task. The root cause is that the conventional analysis methods are not capable of tracking the crack sequence and accounting for the stress relief and re-distribution during cracking. To address this deficiency, the crack queuing algorithm has been proposed. Basically, at each load increment, iterations are carried out and within each iteration step, only the most critical concrete element is allowed to crack and the stress re-distribution is captured in subsequent iteration by re-formulating the cracked concrete element and re-analysing the whole concrete structure. To demonstrate the effectiveness of the crack queuing algorithm, crack analysis of concrete members tested in the literature is performed with and without the crack queuing algorithm incorporated.

Fast Iterative Image Restoration Algorithm

  • Moon, J.I.;Paik, J.K.
    • Journal of Electrical Engineering and information Science
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    • 제1권2호
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    • pp.67-76
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    • 1996
  • In the present paper we propose two new improved iterative restoration algorithms. One is to accelerate convergence of the steepest descent method using the improved search directions, while the other accelerates convergence by using preconditioners. It is also shown that the proposed preconditioned algorithm can accelerate iteration-adaptive iterative image restoration algorithm. The preconditioner in the proposed algorithm can be implemented by using the FIR filter structure, so it can be applied to practical application with manageable amount of computation. Experimental results of the proposed methods show good perfomance improvement in the sense of both convergence speed and quality of the restored image. Although the proposed methods cannot be directly included in spatially-adaptive restoration, they can be used as pre-processing for iteration-adaptive algorithms.

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OFDM 시스템에서 SPW(Sub-Block Phase Weighting) 기법을 이용한 개선된 PAPR 저감 기법 (An Improved PAPR Reduction Using Sub-block Phase Weighting (SPW) Method in OFDM Communication System)

  • 김선애;강영철;서재원;유흥균
    • 한국전자파학회논문지
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    • 제16권11호
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    • pp.1123-1130
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    • 2005
  • 본 논문에서는 PAPR 저감 기법인 SPW(Sub-block Phase Weighting) 기법에서 PAPR(Peak-to-Average Power Ratio)이 저감되도록 조절한 부가 정보를 처리하는 방법을 제안한다. SPW기법은 입력 데이터를 여러 개의 서브블록으로 나누고 위상 회전 벡터를 곱해주는 것으로 피크 전력을 줄여준다. SPW 기법은 부반송파 수와 변조방식, 서브 블록의 수가 PTS 기법과 같을 때 서로 유사한 점을 지니고 있지만, 오직 한 개의 IFFT(Inverse Fast Fourier Transform)를 사용한다는 점에서 기존의 PTS(Partial Transmit Sequence)나 SLM(Selected Mapping) 기법과는 다르다. SPW기법은 비록 PAPR을 효율적으로 줄일 수 있지만 계산 복잡도 문제는 여전히 존재한다. 본 논문에서는 위상 조절을 위 한 방법으로서 flipping 알고리즘과 full iteration 알고리즘을 사용하였다. 컴퓨터 시뮬레이션을 통하여 제안 방식의 특성을 분석하고 성능을 검토하였다.

반도체 레이저의 열적 특성 평가 (Thermal property evaluation of semiconductor laser)

  • 박경현
    • 한국광학회:학술대회논문집
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    • 한국광학회 1990년도 제5회 파동 및 레이저 학술발표회 5th Conference on Waves and lasers 논문집 - 한국광학회
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    • pp.79-81
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    • 1990
  • Temperature distribution of laser diode chip mounted on ideal heat kink was calculated by numerical analysis. In numerical analysis, infinite difference method and Gauss-Scidel iteration was adopted on the basis of two dimensional heat conduction phenomena. As a result, temperature increase of active medium of laser diode driven at 60mA was calculated to be 1.47$^{\circ}C$

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A HYBRID VOLTERRA-TYPE EQUATION WITH TWO TYPES OF IMPULSES

  • Belbas S.A.;Park Jong-Seo
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제13권2호
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    • pp.121-136
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    • 2006
  • We formulate and analyze a hybrid system model that involves Volterra integral operators with multiple integrals and two types of impulsive terms. We give a constructive proof, via an iteration method, of existence and uniqueness of solutions.

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On the ridge estimations with the correlated error structure

  • Won, Byung-Chool
    • 한국경영과학회:학술대회논문집
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    • 대한산업공학회/한국경영과학회 1990년도 춘계공동학술대회논문집; 한국과학기술원; 28 Apr. 1990
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    • pp.263-271
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    • 1990
  • In this paper, we shall construct a ridge estimator in a multiple linear model with the correlated error structure. The existence of the biasing parameter satisfying the Mean Squared Error Criterion is also proved. Furthermore, we shall determine the value of shrinkage factors by the iteration method.

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Adaptive Kernel Density Estimation

  • Faraway, Julian.;Jhun, Myoungshic
    • Communications for Statistical Applications and Methods
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    • 제2권1호
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    • pp.99-111
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    • 1995
  • It is shown that the adaptive kernel methods can potentially produce superior density estimates to the fixed one. In using the adaptive estimates, problems pertain to the initial choice of the estimate can be solved by iteration. Also, simultaneous recommended for variety of distributions. Some data-based method for the choice of the parameters are suggested based on simulation study.

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신경망에 의한 초성자음(ㄱ, ㄷ, ㅂ)의 인식방법 (The methods of recognition of consonants(voiced stops) by Neural Network)

  • 김석동
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1991년도 학술발표회 논문집
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    • pp.73-77
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    • 1991
  • As the basic analysis to solve the stop consonants in phoneme based speech recognition using Back Propagation learning algorithm, changes in hidden units, training set and iteration. Also we propose an efficient processing method of separation between consonants and vowels.

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On the Ridge Estimations with the Corrlated Error Structure

  • Won, Byung Chool;Kim, Hae Kyung
    • 호남수학학술지
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    • 제9권1호
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    • pp.99-111
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    • 1987
  • In this paper we shall construct a ridge estimator in a multiple linear model with the correlated error structure. The existence of the biasing parameter satisfying the Mean Squared Error Criterion is also proved. Furthermore, we shall determine the value of shrinkage factors by the iteration method.

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