• 제목/요약/키워드: Adaptive scheme

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

  • ;전병우
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2019년도 추계학술대회
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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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로보트 매니퓰레이터의 비집중 적응제어에 관한 연구 (A study on decentralized adaptive control of robot manipulator)

  • 이상철;박성기;정찬수
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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    • pp.183-187
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    • 1989
  • This paper presents on approach to the position control of a robot manipulator by using a decentralized adaptive control scheme. The large scale system is regarded as the system which consists of many subsystems having interconnection. In each subsystem, a local control system is composed by feedforward and feedback component, one computes the nominal torque from the Newton-Euler equation, the other computes the perturbation equation which reduce the position error of the manipulator along the nominal trajectory. A computer simulation studies was conducted to evaluate and compare the performances of the proposed manipulator control scheme with those of the PD control and centralized control schemes.

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ADAPTIVE CHANGE OF CODE RATE IN DS-SSMA COMMUNICATION SYSTEMS

  • Youngkwon-Ryu;Jinsoo-Bae;Iickho-Song
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송공학회 1995년도 학술대회
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    • pp.59-61
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    • 1995
  • An adaptive code rate change scheme in DS-SSMA systems is proposed. In the proposed scheme, the error correcting code rate is changed according to the channel state, the effective number of users. The channel state is estimated based on retransmission requests. The criterion for the change of the code rate is to maximize the throughput under given error bound.

스위치드 릴럭턴스 전동기의 적응운전방식에 관한 연구 (An Adaptive Operation Scheme of Switched Reluctance Motor)

  • 이치우;오석규;이일천;황영문
    • 대한전기학회:학술대회논문집
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    • 대한전기학회 1997년도 하계학술대회 논문집 A
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    • pp.44-46
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    • 1997
  • The intrinsic simplicity, ruggedness, and simple power electronic drive requirement of a switched reluctance motor (SRM) make it a viable use for many commercial adjustable speed applications. However, higher torque ripple is one of the few disadvantages of the SRM drives. This paper describes the robust control scheme that permits the phase torque flatted by adaptive reference model.

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적응 뉴럴-퍼지 제어시스템의 설계에 관한 연구 (On Designing an Adaptive Neural-Fuzzy Control System)

  • 김성현;김용호;최영길;심귀보;전홍태
    • 전자공학회논문지A
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    • 제30A권4호
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    • pp.37-43
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    • 1993
  • As an approach to develope the intelligent control scheme, this paper will propose an adaptive neural-fuzzy control scheme. The proposed neural-fuzzy control system, which consists of the Fuzzy-Neural Controller(FNC) and Model Neural Network(MNN), has two important characteristics of adaptation and learning. The error back propagation algorithm has been adopted as a learning technique.

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일련의 상호연결된 연속시간 시스템에 대한 비집중적응 제어기의 설계 (Decentralized Adaptive Controller Design for a Class of Interconnected Continuous Systems)

  • 류준;김병연
    • 전자공학회논문지B
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    • 제29B권10호
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    • pp.53-58
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    • 1992
  • This paper presents a decentralized model reference adaptive control scheme for an interconnected linear system composed of a number of single-input single-output subsystems in which outgoing interactions pass through the measurement channel and are subjected to bounded external disturbances. The scheme can treat the unknown strength of interactions as well as uncertainties in subsystem dynamics, and allows for the case when the relative degree of each decoulped subsystem does not exceed two.

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Trellis Defection of Tamed FM with the DLMS and Convergence

  • Kang, Min-Goo;Lee, Yang-Won;Cho, Hyung-Rae;Kang, Sung-Chul
    • 한국정보통신학회논문지
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    • 제1권2호
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    • pp.199-207
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    • 1997
  • The Maximum Likelihood Sequence Estimation scheme is modified to improve the error performance of the correlative coding in the Tamed FM. To remove intersymbol interference, the Decision Feedback Equalization scheme with the delayed LMS algorithm and the Viterbi algorithm(10-symbol delay) in the delayed adaptive equalization are proposed for the performance of decision-directed adaptive equalization under the High Frequency channels, and the condition of convergence is analyzed.

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HEVC 영상압축을 위한 적응적 스칼라 양자화 (Adaptive Scalar Quantization for HEVC Video Coding)

  • ;전병우
    • 한국방송∙미디어공학회:학술대회논문집
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    • 한국방송∙미디어공학회 2019년도 하계학술대회
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    • pp.114-115
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    • 2019
  • This paper introduces an adaptive scalar quantization scheme for video coding technology. The method utilizes the property of the coefficient groups (CG) inside each transform block so that the dead-zone interval of the scalar quantizer is adaptively set up for different CGs. Its experimental results show that our proposed quantization scheme can achieve BDBR reduction of 4.75%, 5.93, and 5.16% for Y, Cb, and Cr channel respectively when encoding with HEVC.

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A Distributed Power Optimization Method for CDMA Cellular Mobile Systems Using an Adaptive Search Scheme

  • Lee, Young-Dae
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2003년도 ICCAS
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    • pp.1982-1985
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    • 2003
  • Future cellular networks will mainly be driven by, high quality channels, high band with utilization, low power consumption and efficient network management. For a given channel allocation, the capacity and quality of communication of cellular radio systems using CDMA(Code Division Multiple Access) can be increased by using a transmitter power control scheme to combat the near-far problem. Centralized power control schemes or distributed ones to maximize the minimum signal-to-interference in each user of CDMA wireless network have been investigated. This paper has proposed a distributed power control algorithm, which employs an adaptive search scheme, in order to solve quickly the linear systems of equations for power update in CDMA cellular radio systems. The simulation results show that the proposed scheme has faster convergence rate than the typical bang-bang type of distributed power control algorithm, which has been much used as a reference algorithm in IS-95A and W-CDMA communication network.

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A Novel Adaptive Routing Scheme for the QoS-Based Multimedia Services in Mobile Ad-Hoc Networks

  • 이창범;김영웅;소성렬;김영권
    • 전기전자학회논문지
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    • 제4권2호
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    • pp.281-287
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    • 2000
  • A mobile ad-hoc network is composed of only mobile nodes, which are distributed dynamically, without any wired backbone or centralized entities. Since the existing works on ad-hoc routing protocol are mostly biased toward a military application, we need a new routing scheme for a support of multimedia services in mobile ad-hoc networks. Therefore, we propose a novel scheme that can support a variety of traffic attributes and can be applicable to high-speed and multimedia data services in mobile ad-hoc networks by using adaptive transmission power level. As a result of simulation, the proposed scheme has better performance than conventional method, which is performed with uniform transmission power level, in view of route query delay time.

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