• 제목/요약/키워드: Adaptive algorithms

검색결과 1,194건 처리시간 0.028초

승산을 요하지 않는 적응 디지탈 필터 (Multiplication Free Adaptive Digital Filter)

  • 박태호;차일환;윤대희
    • 한국음향학회지
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    • 제6권2호
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    • pp.15-18
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    • 1987
  • 승산을 요하지 않는 적응 디지탈 필터링 알고리즘이 논의되었다. 제안된 알고리즘은 델타 변조 디지탈 필터를 사용하였으며 승산없이 적응 디지탈 필터를 실현하기 위하여 필터계수는 SIGN 알고리즘으로 새로이 재조정된다. 결과적으로, 제안된 알고리즘은 단순히 UP/DOWN 계수동작으로 실현될 수 있음을 보였다. 제안된 적응 디지탈 필터링 알고리즘과 다른 알고리즘을 시스템 Identification문제에 적용하여 수렴특성을 조사하였다.

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TCP/IP 네트워크에서 적응적 큐 관리 알고리즘 (Adaptive Queue Management in TCP/IP Networks)

  • 김창희
    • 디지털산업정보학회논문지
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    • 제6권2호
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    • pp.153-167
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    • 2010
  • Traffic conditions, in particular number of active TCP flows, change dramatically over time. The main goal of this paper is an adaptive queue management algorithm that can maintain network state of high-throughput and low-delay under changing traffic conditions In this paper, we devise Probability Adaptive RED(PARED) that combines the more effective elements of recent algorithms with a RED core. It automatically adjusts its adaptive marking function to account for changes in traffic load and to keep queue length within the desired target queue length. We simulate that PARED algorithm results in under changes in traffic load and mixed traffic load. The simulation test confirm this stability, and indicate that overall performances of PARED are substantially better than the RED and ARED algorithms.

A Fuzzy Variable Step Size LMS Algorithm for Adaptive Antennas in CDMA Systems

  • Su, Pham-Van;Tuan, Le-Minh;Kim, Jewoo;Giwan Yoon
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2002년도 춘계종합학술대회
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    • pp.518-522
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    • 2002
  • This paper proposes a new application of Fuzzy logic to Variable Step Size Least Mean Square (VS-LMS) adaptive beamforming algorithm in CDMA systems. The proposed algorithm adjusts the step size of the Least Mean Square (LMS) by using the application of Fuzzy logic in which the increase or decrease of step size depends on the fuzzy inference results of the Mean Square Error (MSE). Computer simulation results show that the proposed algorithm has a better capacity of tracking compared with the conventional LMS algorithms and other variable step size LMS algorithms.

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유전알고리즘에서 적응적 연산자들의 비교연구 (Comparison of Adaptive Operators in Genetic Algorithms)

  • Yun, Young-Su;Seo, Seoun-Lock
    • 지능정보연구
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    • 제8권2호
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    • pp.189-203
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    • 2002
  • 이 논문에서 우리는 유전알고리즘의 적응적 연산자에 대한 수행도를 비교한다. 이러한 적응적 연산자를 위해서, 유전알고리즘의 교차변이와 돌연변이 연산자가 고려되어 지며, 이 논문에서 개발된 하나의 퍼지로직 제어기와 기존연구에서 사용된 두개의 휴리스틱 기법이 제시되어진다. 이러한 퍼지로직 제어기와 두개의 기존 휴리스틱 기법들은 유전 탐색과정 동안에 그 연산자의 비율들을 적응적으로 조절한다. 이 논문에서 제시된 모든 알고리즘들은 수치예제에서 분석되어 지며, 결론적으로 이들 알고리즘 중에서 최적의 알고리즘이 추천된다.

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대규모 위상배열용 적응 빔 형성 알고리듬의 성능비교 (Performance comparisons of adaptive beamforming algorithms for a large distorted phased array)

  • 강봉순;박성균
    • 전자공학회논문지S
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    • 제35S권7호
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    • pp.46-52
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    • 1998
  • This paper presents an experimenal proof for criteria of selecting an optimum adaptive beamforming (ABF) algorithm for a large distorted phased array. A single point target embedded in clutter model is suggested to compare four well-known ABF algorithms. These algorithms are tested to low variance and high variance real data for self-calibrating a large distored phased array. It is shown that these algorithms require at least one dominant scatterer with large radar cross section (RCS) or multiple scatterers with moderate RCS in the field of view. Experimental results are provided to demonstrate the comparisons of the four algorithems in terms of gain loss and image correlaion coefficient, along with corresponding reconstructed cross-range images and range-azimuth images.

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LCD 결함 검출을 위한 머신 비전 알고리즘 연구 (Study on Machine Vision Algorithms for LCD Defects Detection)

  • 정민철
    • 반도체디스플레이기술학회지
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    • 제9권3호
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    • pp.59-63
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    • 2010
  • This paper proposes computer visual inspection algorithms for various LCD defects which are found in a manufacturing process. Modular vision processing steps are required in order to detect different types of LCD defects. Those key modules include RGB filtering for pixel defects, gray-scale morphological processing and Hough transform for line defects, and adaptive threshold for spot defects. The proposed algorithms can give users detailed information on the type of defects in the LCD panel, the size of defect, and its location. The machine vision inspection system is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiment results show that the proposed algorithms are quite successful.

A Least Squares Approach to Escalator Algorithms for Adaptive Filtering

  • Kim, Nam-Yong
    • ETRI Journal
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    • 제28권2호
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    • pp.155-161
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    • 2006
  • In this paper, we introduce an escalator (ESC) algorithm based on the least squares (LS) criterion. The proposed algorithm is relatively insensitive to the eigenvalue spread ratio (ESR) of an input signal and has a faster convergence speed than the conventional ESC algorithms. This algorithm exploits the fast adaptation ability of least squares methods and the orthogonalization property of the ESC structure. From the simulation results, the proposed algorithm shows superior convergence performance.

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RLS 알고리즘에 기반을 둔 블라인드 채널 추정 (Blind Channel Estimator based on the RLS algorithm)

  • 서우정;하판봉;윤태성
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 추계종합학술대회 논문집
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    • pp.655-658
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    • 1999
  • In this study, We derived Recursive Least Squares(RLS) algorithm with adaptive maximum -likelihood channel estimate for digital pulse amplitude modulated sequence in the presence of intersymbol interference and additive white Gaussian noise. RLS algorithms have better convergence characteristics than conventional algorithms, LMS Least Mean Squares) algorithms.

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블록 영상의 통계적 특성을 이용한 적응적 상황 검출 알고리즘 (An Adaptive Event Detection Algorithm Based on Statistics of Subblock Images)

  • 하영욱;김희태
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.875-878
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    • 1998
  • In this paper, an adaptive event detection algorithm is proposed, for which we use the statistics of subblock image and adaptive threshold levels. The adaptive threshold level for a parameter binarization is taken by averaging the corresponding paramerter obtained from several input images. As simulation results, it is shown that the proposed algorithm is much more adaptive to the input images and effective in event detection rate than the conventional difference based algorithms.

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적응요소분할법에 의한 평면곡선가공의 공구경로 결정 - 적응요소직선보간과 적응요소포물선보간 및 혼합보간법의 비교 - (The Tool Path Determination for Machining the Plane Curve by an Adaptive Mesh Generation Technique - Comparision among the Adaptive Linear Interpolation, Parabolic Interpolation & Linear-Parabolic Interpolation Method -)

  • 현창헌
    • 산업기술연구
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    • 제12권
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    • pp.69-76
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    • 1992
  • An attempt has been made to determination the NC milling machine's tool-path through the adaptive parabolic interpolation method & the adaptive linear-parabolic interpolation method in consideration of the economical machining time. The algorithms for the above-mentioned interpolation methods have been designed and the numerical experiments for these methods have been conducted with the existing adaptive linear interpolation methods for comparision.

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