• Title/Summary/Keyword: Rate-adaptive

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An Adaptive Block Truncation Coding Using Human Visual System (인간시각 체계를 이용한 적응 구획 절단 부호화)

  • 신용달;이봉락;이건일
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.30B no.12
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    • pp.67-72
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    • 1993
  • An adaptive block truncation coding(BTC) using human visual system(HVS) is proposed. To reduce visible blocking effect at sensitive area in HVS. a new category classification coefficient is proposed. The categroy classification coefficient was derived by combining the modified HVS and standard deviation. By computer simulations, we showed that the proposed method reduced blocking effect at low bit rate coding more than the conventional Hui's method.

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Frequency Adaptive Hard-Decision Quantization for Video Coding (영상 부호화를 위한 주파수 적응형 경판정 양자화)

  • Xu, Motong;Jeon, Byeungwoo
    • Proceedings of the Korean Society of Broadcast Engineers Conference
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    • 2019.11a
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    • pp.194-195
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    • 2019
  • In this paper, we propose a frequency location adaptive hard-decision quantization (HDQ) scheme for video coding. A threshold for zero quantized level is adaptively applied to unquantized transform coefficients based on its frequency location in the transform domain. The proposed method achieves an average of 1.13%, 1.57%, and 1.53% of bit-rate reduction in BDBR sense compared to the conventional HDQ scheme respectively in Y, Cb, and Cr under the all intra encoding configuration.

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Adaptive Control of Multiplexed Closed Circuit Anesthesia

  • Jee, Gyu-In;Roy, Rob
    • Proceedings of the KOSOMBE Conference
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    • v.1992 no.05
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    • pp.79-81
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    • 1992
  • This paper describes the design of an adaptive closed circuit anesthesia controller based on a multiplexed mass spectrometer system. The controller deals with measurement deterioration caused by measurement delay and rise time through a tong catheter as well as long sampling times due to the multiplexed measurements. Measurement data is extrapolated between sampling periods to increase the estimation convergence rate. A multiple-step-ahead predictive control algorithm is used to calculate intermediatc control inputs between sampling intervals. Simulations are used to validate the designed controller.

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Control of induction motors using adaptive fuzzy feedback linearization techniques (적응 퍼지 궤환선형화기법을 이용한 유도전동기의 제어)

  • 류지수;김정중;이기상
    • 제어로봇시스템학회:학술대회논문집
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    • 1996.10b
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    • pp.1253-1256
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    • 1996
  • In this paper, a new nonlinear feedback linearization control scheme for induction motors is developed. The control scheme employs a fuzzy nonlinear identification scheme based on fuzzy basis function expansion to adoptively compensate the parameter variations, i.e. rotor resistance, mutual and self inductance etc. An important feature of the proposed control scheme is to incorporate the sliding mode controller into the scheme to speed up convergence rate. Simulation tests show the robust behavior of the proposed controller in the presence of the parameter uncertainties of the machine.

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Comparison Error of Signal Interpolation Methods for Vibration Signal Analysis of Revolution Machine (회전체의 진동신호분석을 위한 신호보간의 오차분석)

  • Park Jun-Yong;Park Chong-Yeon
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.53 no.12
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    • pp.820-826
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    • 2004
  • In this paper, studied error of various signal interpolation methods in vibration signal analysis with digital order tracking. Because, interpolation errors are related with sampling rate and amount of calculation. Appled Signal interpolation methods are Lagrange, Newton and Cubic-spline. This paper proposed more proper interpolation method. Also, we suggest guideline for adaptive application of signal interpolation methods with Calculated results.

Optical Implementation of Single-Layer Adaptive Neural Network for Multicategory Classification. (다영상 분류를 위한 단층 적응 신경회로망의 광학적 구현)

  • 이상훈
    • Proceedings of the Optical Society of Korea Conference
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    • 1991.06a
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    • pp.23-28
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    • 1991
  • A single-layer neural network with 4$\times$4 input neurons and 4 output neurons is optically implemented. Holographic lenslet arrays are used for the e optical interconnection topology, a liquid crystal light valve(LCLV) is used for controlling optical interconection weights. Using a Perceptron learning rule, it classifics input patterns into 4 different categories. It is shown that the performance of the adaptive neural network depends on the learning rate, the correlation of input patterns, and the nonlinear characteristic properties of the liquid crystal light valve.

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A study on the application of directed adaptive control with plant augmentation to space station (우주 기지에 대한 플랜트 확장이 부가된 직접 적응제어에 관한 연구)

  • 양성현;이기서
    • 제어로봇시스템학회:학술대회논문집
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    • 1987.10b
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    • pp.550-555
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    • 1987
  • In this study, the construction process of a two-panel space station and its control problem are discussed. The appliability of direct model reference adaptive control technique with plant augmentation is investigated. Regulator control problem with high initial transient has been simulated Result show that high rate of convergence has been observed for all the simulation.

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On Predictive Coding of Speech Signals (음성신호의 예측부호화에 관하여)

  • 은종관
    • The Magazine of the IEIE
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    • v.12 no.5
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    • pp.23-35
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    • 1985
  • 본 논문은 디지털 음성통신에서 사용되는 예측부호화(predictive coding) 방식에 관하여 기술하고 있다. 특히 전송속도가 16∼48kbit/s 대역에서 많이 사용하고 있는 adaptive differential pulse code modulation(ADPCM)과 adaptive delta modulation(ADM)에 관하여 중점적으로 토의한다. 또한 variable-rate ADPCM과 ADM에 관해서 기술하고, 이들 시스템의 noisy channel에서의 효과 및 성능개선방법, 그리고 PCM과의 transcoding에서의 문제점 등을 통의한다. ADPCM은 최근 CCITT에서의 표준화 결과로 앞으로 PCM과 함께 많이 쓰여질 전망이며, ADM은 시스템이 간단하고 또한 channel error에 강한 이유로 특수통신에 많이 쓰여질 것이다.

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Adaptive On-line Optimization of Cellular Productivity of Continuous Methylotroph Culture (메타놀자화균의 연속배양에 의한 균체생산의 온-라인 적응최적화)

  • 이형춘;박정오
    • The Korean Journal of Food And Nutrition
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    • v.1 no.2
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    • pp.31-36
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    • 1988
  • An adaptive on-line optimization method has been applied to test the ability to maximize the cellular productivity of a continuous methylotroph culture system which was simulated by a variable yield Monod-type model. Optimum dilution rate and productivity were successively obtained and maintained at all times by the algorithm that utilizes steepest descent technique as optimization method and recursive least-square method with forgetting factor as dynamic model identification.

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