• 제목/요약/키워드: adaptive method

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움직임 보상을 통한 움직임 기반의 De-interlacing 기법 (A Motion-Adaptive De-interlacing Method using Motion Compensated Interpolation)

  • 이성규;강석규;이동호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2001년도 제14회 신호처리 합동 학술대회 논문집
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    • pp.371-374
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    • 2001
  • 본 논문에서는 움직임 보상을 이용한 Motion-Adaptive De-interlacing Method를 제안 한다. 정확한 움직임 추정을 위해서 Pre-filter로서 EBMF(Edge Based Median Filter)를 사용하며 새로운 Block Matching Method를 제안한다. Temporal Filter로서 Motion Missing Error를 제거하기 위해 입력 영상의 움직임 영역에 따라 각각 다른 임계 값을 적용하는 AMPDF(Adaptive Minimum Pixel Difference Filter)를 적용하였으며 MMD(Maximum Motion Detection)와 SAD(Sum of Difference)를 이용하여 빠른 움직임 영역에서 화질을 향상시켰다. 최종적으로 잘못된 움직임 보상에 기인하는 화질의 열화를 방지하기 위한 Motion Correction Filter를 제안한다.

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퍼지 신경 회로망을 이용한 혼돈 비선형 시스템의 간접 적응 제어기 설계 (The Design of Indirect Adaptive Controller of Chaotic Nonlinear Systems using Fuzzy Neural Networks)

  • 류주훈;박진배최윤호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1998년도 추계종합학술대회 논문집
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    • pp.437-440
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    • 1998
  • In this paper, the design method of fuzzy neural network(FNN) controller using indirect adaptive control technique is presented for controlling chaotic nonlinear systems. Firstly, the fuzzy model identified with a FNN in off-line process. Secondly, the trained fuzzy model tunes adaptively the control rules of the FNN controller in on-line process. In order to evaluate the proposed control method, Indirect adaptive control method is applied to the representative continuous-time chaotic nonlinear systems, that is, the Duffing system and the Lorenz system. Simulations are done to verify the effectivencess of controller.

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Fault Detection by Using an Adaptive Observer

  • Inoue, A.;Deng, M.;Yoshinaga, S.
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 2005년도 ICCAS
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    • pp.710-713
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    • 2005
  • In this paper, a design method to detect faults in plants with uncertainties is proposed. When a plant has faults, the plant will be corrupted by an unknown fault signal. In addition, the plant also includes uncertainties, such as disturbances and plant parameter deviations. In this case, the proposed method estimates the fault signal by using an adaptive observer. Numerical examples are given to demonstrate the validity of the proposed method.

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선형시스템을 위한 개선된수렴속도를 갖는 기준모델 적응제어기- SYNTHESIS METHOD (Model Reference Adaptive Control for Linear System with Improved Convergence Rate -SIGNAL SYNTHESIS METHOD-)

  • Lim, Kye-Young
    • 대한전기학회논문지
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    • 제37권10호
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    • pp.733-739
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    • 1988
  • Adaptive controllers for linear system whose nominal values of coefficients only are known, that is corrupted by disturbance, are designed by signal synthesis model reference adaptive control (MRAC). This design is stemmed from the Lyapunov direct method. To reduce the model following error and to improve the conrergence rate of the design, an indirect suboptimal control law is de rived using the Hamilton Jacobi Beellman equation. Proper compensaton for the effects of time varying coefficients and plant disturbance are suggested. In the design procedure no complete identification of unknown coefficients are required.

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에너지 효율과 적응변조를 이용한 이동통신 시스템의 효율적인 데이터 전송방법 (Effective Transmission Method using Energy Efficient Adaptive Modulation)

  • 오의교
    • 디지털융복합연구
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    • 제10권9호
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    • pp.369-374
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    • 2012
  • 통신 시스템의 설계 전력 여유분을 이용하여 기존 시스템의 구성을 변경하지 않고 시스템의 전반적인 전송효율을 증진시킬 수 있는 적응변조방식의 변환은 주로 전송량에 대한 관점에서 다루었으나, 변조방식의 변환 시 소모되는 순간 에너지는 이동통신 단말과 같이 밧데리가 필요한 장치의 효율을 낮춘다. 따라서 전송효율만을 고려하던 기존방식에 순간 에너지소비의 관점을 도입하여 에너지 효율을 고려한 변환기법을 제안한다.

합, 차 빔 내에서 가섭 신호 동시 제거를 위한 적응 위상 모노펄스 (Adaptive phase monopulse for simultaneous interference cancellation in sum and difference beams)

  • 주경환;성하종;윤대희
    • 전자공학회논문지B
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    • 제33B권3호
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    • pp.142-150
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    • 1996
  • Monopulse technique has been widely used for a bearing estimation of a desired signal. This method can estimate the bearing of the signal with only one pulse, so computational load and complexity are low and its processes are simple. But if the desired signal incidents with interferences or multiple signals exist in the beams, the method fails to estimate correct signal angle. To solve this problem, the method to use adaptive array was proposed. In conventional adaptive array methods, sum beam was formed with fixed weights and ifference beam was formed with adaptive weights determined to minimize beamformer output power with one or more linear constraints, or an algorithm to minimize each sum beam and difference beams simultaneously using adaptively formed one basic beam. Theroretical analyses and simulation results show that the performance of the proposed method is superior to that of conventional algorithms.

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Adaptive Control of Strong Mutation Rate and Probability for Queen-bee Genetic Algorithms

  • Jung, Sung-Hoon
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제12권1호
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    • pp.29-35
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    • 2012
  • This paper introduces an adaptive control method of strong mutation rate and probability for queen-bee genetic algorithms. Although the queen-bee genetic algorithms have shown good performances, it had a critical problem that the strong mutation rate and probability should be selected by a trial and error method empirically. In order to solve this problem, we employed the measure of convergence and used it as a control parameter of those. Experimental results with four function optimization problems showed that our method was similar to or sometimes superior to the best result of empirical selections. This indicates that our method is very useful to practical optimization problems because it does not need time consuming trials.

Pupil Detection using Multistage Adaptive Thresholding and Circular Hough Transform

  • Navastara, Dini Adni;Park, Hyun-Jun;Cha, Eui-Young
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2013년도 추계학술대회
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    • pp.90-93
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    • 2013
  • This paper presents a multistage adaptive thresholding method and circular Hough transform for pupil detection. Multistage adaptive thresholding is a thresholding method that applies local image statistic within a neighborhood variable and the global thresholds. Therefore, the method can adopt the benefit of local thresholding and prevent an over segmentation at the same time because of the global image information. To detect a pupil, a circular Hough transform is applied to it in which the pupil pattern is considered as a circle shape. The experimental results show the reliability of our proposed method in detecting pupil properly.

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적응제어 기법을 적용한 ABS의 바퀴 슬립 제어 (Wheel Slip Control of ABS Using Adaptive Control Method)

  • 최종환
    • 한국기계가공학회지
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    • 제5권3호
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    • pp.71-79
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    • 2006
  • ABS is a safety device for preventing wheel locking in a sudden baking. Its control methods are classified into three types; deceleration control, wheel slip control and deceleration/acceleration control. The braking force takes the influence of the friction coefficient between road and tire, which in turn depends on the wheel slip as well as road conditions. In this paper, it has been proposed the wheel slip control system to apply the adaptive control method at the ABS. To maintain wheel slip to desired wheel slip, it have been done the linearization and designed the adaptive controller to apply gradient method based on the reference model. It is illustrated by computer simulations that the proposed control system gives good performances and adaptation to parameter variation.

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An Adaptive Frequency Hopping Method in the Bluetooth Baseband

  • Moon, San-Gook
    • 한국정보통신학회:학술대회논문집
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    • 한국해양정보통신학회 2005년도 춘계종합학술대회
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    • pp.785-787
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    • 2005
  • In the Bluetooth specification version 1.0, one specific frequency in one piconet was created depending upon the device clock and the Bluetooth native address at one specific time slot in the frequency hopping method. The basic hopping pattern was arranging the 79 ISM frequency band in pseudo-random fashion. Possible problem is the chance of collision of ownership of one specific frequency by more than 2 wireless devices when they are within the communication-active range. In this paper, we propose the adaptive frequency hopping method in order to resolve the possible problem so that more than 2 wireless devices communicates with their own client devices without being interfered. The proposed method was implemented with HDL later to be synthesized with an automatic EDA synthesizer and verified as well. The implemented adaptive frequency hopping circuit operated normally at 24MHz which will be the target clock frequency of the target Bluetooth device.

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