• Title/Summary/Keyword: Adaptive estimation

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Development of Sound Source Localization System using Explicit Adaptive Time Delay Estimation

  • Kim, Doh-Hyoung;Park, Youngjin
    • 제어로봇시스템학회:학술대회논문집
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    • 2002.10a
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    • pp.80.2-80
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    • 2002
  • The problem of sound source localization is to determine the position of sound sources using the measurement of the acoustic signals received by microphones. To develop a good sound source localization system which is applicable to a mobile platform such as robots, a time delay estimator with low computational complexity and robustness to background noise or reverberations is necessary. In this paper, an explicit adaptive time delay estimation method for a sound source localization system is proposed. Proposed explicit adaptive time estimation algorithm employs direct adaptation of the delay parameter using a transform-based optimization technique, rather than...

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On-line Parameter Estimator Based on Takagi-Sugeno Fuzzy Models

  • Park, Chang-Woo;Hyun, Chang-Ho;Park, Mignon
    • Journal of the Korean Institute of Intelligent Systems
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    • v.12 no.5
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    • pp.481-486
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    • 2002
  • In this paper, a new on-line parameter estimation methodology for the general continuous time Takagi-Sugeno(T-5) fuzzy model whose parameters are poorly known or uncertain is presented. An estimator with an appropriate adaptive law for updating the parameters is designed and analyzed based on the Lyapunov theory. The adaptive law is designed so that the estimation model follows the plant parameterized model. By the proposed estimator, the parameters of the T-S fuzzy model can be estimated by observing the behavior of the system and it can be a basis for the indirect adaptive fuzzy control. Based on the derived design method, the parameter estimation for controllable canonical T-S fuzzy model is also Presented.

A Hybrid Estimation of Distribution Algorithm with Differential Evolution based on Self-adaptive Strategy

  • Fan, Debin;Lee, Jaewan
    • Journal of Internet Computing and Services
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    • v.22 no.1
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    • pp.1-11
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    • 2021
  • Estimation of distribution algorithm (EDA) is a popular stochastic metaheuristic algorithm. EDA has been widely utilized in various optimization problems. However, it has been shown that the diversity of the population gradually decreases during the iterations, which makes EDA easily lead to premature convergence. This article introduces a hybrid estimation of distribution algorithm (EDA) with differential evolution (DE) based on self-adaptive strategy, namely HEDADE-SA. Firstly, an alternative probability model is used in sampling to improve population diversity. Secondly, the proposed algorithm is combined with DE, and a self-adaptive strategy is adopted to improve the convergence speed of the algorithm. Finally, twenty-five benchmark problems are conducted to verify the performance of HEDADE-SA. Experimental results indicate that HEDADE-SA is a feasible and effective algorithm.

A Real-time Multiview Video Coding System using Fast Disparity Estimation

  • Bae, Kyung-Hoon;Woo, Byung-Kwang
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.22 no.7
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    • pp.37-42
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    • 2008
  • In this paper, a real-time multiview video coding system using fast disparity estimation is proposed. In the multiview encoder, adaptive disparity-motion estimation (DME) for an effective 3-dimensional (3D) processing are proposed. That is, by adaptively predicting the mutual correlation between stereo images in the key-frame using the proposed algorithm, the bandwidth of stereo input images can be compressed to the level of a conventional 2D image and a predicted image also can be effectively reconstructed using a reference image and adaptive disparity vectors. Also, in multiview decoder, intermediate view reconstruction (IVR) using adaptive disparity search algorithm (DSA) for real-time multiview video processing is proposed. The proposed IVR can reduce a processing time of disparity estimation by selecting adaptively disparity search range. Accordingly, the proposed multiview video coding system is able to increase the efficiency of the coding rate and improve the resolution.

Adaptive Current Control Scheme of PM Synchronous Motor with Estimation of Flux Linkage and Stator Resistance

  • Kim, Kyeoug-Hwa;Baik, In-Cheol;Chung, Se-Kyo;Youn, Myung-Joong
    • Proceedings of the KIPE Conference
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    • 1996.06a
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    • pp.17-20
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    • 1996
  • An adaptive current control scheme of a permanent magnet (PM) synchronous motor with the simultaneous estimation of the magnitude of the flux linkage and stator resistance is proposed. The adaptive parameter estimation is achieved by a model reference adaptive system (MRAS) technique. The adaptive laws are derived by the Popov's hyperstability theory and the positivity concept. The predictive control scheme is employed for the current controller with the estimated parameters. The robustness of the proposed current control scheme is compared with the conventional one through the computer simulations.

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Adaptive Robust Control for Robot Manipulator with the Uncertain Bound Estimation and Implementation (불확실성의 경계를 추정하는 로봇 매니퓰레이터의 적응견실제어기 설계 및 실험)

  • 한명철;하인철
    • Journal of Institute of Control, Robotics and Systems
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    • v.10 no.4
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    • pp.312-316
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    • 2004
  • In this paper, it is presented an adaptive robust control system to implement real-time control of a robot manipulator. There are Quantitative or qualitative differences between a real robot manipulator and a robot modeling. In order to compensate these differences, uncertain factors are added to a robot modeling. The uncertain factors come from imperfect knowledge of system parameters, payload change, friction, external disturbance, etc. Also, uncertainty is often nonlinear and time-varying. In the proceeding work, we proposed a class of robust control of a robot manipulator and provided the stability analysis. In the work, we propose a class of adaptive robust control of robot manipulator with bound estimation. Through experiments, the proposed adaptive robust control scheme is proved to be an efficient control technique for real-time control of a robot system using DSP.

Adaptive Flux Observer with On-line Inductance Estimation of an Interior PM Synchronous Machine Considering Magnetic Saturation

  • Jeong, Yu-Seok;Lee, Jun-Young
    • Journal of Power Electronics
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    • v.9 no.2
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    • pp.188-197
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    • 2009
  • This paper presents an adaptive flux observer to estimate stator flux linkage and stator inductances of an interior permanent-magnet synchronous machine considering magnetic saturation. The concept of static and dynamic inductances due to saturation is introduced in the machine model to describe the relationship between current and flux linkage and the relationship between their time derivatives. A flux observer designed in the stationary reference frame with constant inductance is analyzed in the rotor reference frame by a frequency-response characteristic. An adaptive algorithm for an on-line inductance estimation is proposed and a Lyapunov-based analysis is given to discuss its stability. The dynamic inductances are estimated by using Taylor approximation based on the static inductances estimated by the adaptive method. The simulation and experimental results show the feasibility and performance of the proposed technique.

SOC Estimation of Flooded Lead Acid Battery Using an Adaptive Unscented Kalman Filter (적응형 Unscented 칼만필터를 이용한 플러디드 납축전지의 SOC 추정)

  • Khan, Abdul Basit;Choi, Woojin
    • Proceedings of the KIPE Conference
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    • 2016.11a
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    • pp.59-60
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    • 2016
  • Flooded lead acid batteries are still very popular in the industry because of their low cost as compared to their counterparts. State of Charge (SOC) estimation is of great importance for a flooded lead acid battery to ensure its safe working and to prevent it from over-charging or over-discharging. Different types of Kalman Filters are widely used for SOC estimation of batteries. The values of process and measurement noise covariance of a filter are usually calculated by trial and error method and taken as constant throughout the estimation process. While in practical cases, these values can vary as well depending upon the dynamics of the system. Therefore an Adaptive Unscented Kalman Filter (AUKF) is introduced in which the values of the process and measurement noise covariance are updated in each iteration based on the residual system error. A comparison of traditional and Adaptive Unscented Kalman Filter is presented in the paper. The results show that SOC estimation error by the proposed method is further reduced by 3 % as compared to traditional Unscented Kalman Filter.

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Inverse active wind load inputs estimation of the multilayer shearing stress structure

  • Chen, Tsung-Chien;Lee, Ming-Hui
    • Wind and Structures
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    • v.11 no.1
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    • pp.19-33
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    • 2008
  • This research investigates the adaptive input estimation method applied to the multilayer shearing stress structure. This method is to estimate the values of wind load inputs by analyzing the active reaction of the system. The Kalman filter without the input term and the adaptive weighted recursive least square estimator are two main portions of this method. The innovation vector can be produced by the Kalman filter, and be applied to the adaptive weighted recursive least square estimator to estimate the wind load input over time. This combined method can effectively estimate the wind loads to the structure system to enhance the reliability of the system active performance analysis. The forms of the simulated inputs (loads) in this paper include the periodic sinusoidal wave, the decaying exponent, the random combination of the sinusoidal wave and the decaying exponent, etc. The active reaction computed plus the simulation error is regard as the simulated measurement and is applied to the input estimation algorithm to implement the numerical simulation of the inverse input estimation process. The availability and the precision of the input estimation method proposed in this research can be verified by comparing the actual value and the one obtained by numerical simulation.

Effective Reconstruction of Stereo Image through Regularized Adaptive Disparity Estimation Scheme (평활화된 적응적 변이추정 기법을 이용한 스테레오 영상의 효과적인 복원)

  • Kim, Yong-Ok;Bae, Kyung-Hoon;Kim, Eun-Soo
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.28 no.4C
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    • pp.424-432
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    • 2003
  • In this paper, an effective method of stereo image reconstruction through the regularized adaptive disparity estimation is proposed. Althougth the conventional adaptive disparity estimation method can sharply improve the PSNR of a reconstructed stereo image, but some problems of overlapping between the matching windows and disallocation of the matching windows can be occurred, because the matching window size changes adaptively in accordance with the magnitude of feature values. Accordingly, in thia paper, a new regularized adaptive disparity estimation technique is proposed. That is, by regularizing the estimated disparity vector with the neughboring disparity vectors, problems of the conventional adaptive disparity estimated scheme might be solved, and also the predicted stereo image can be more effectively reconstructed. From some experiments using the CCETT'S stereo image pairs of 'Man' and 'Claude', it is analyzed that the proposed disparity estimation scheme can improve PSNRs of the reconstructed images to 10.89dB, 6.13dB for 'Man' and 1.41dB, 0.81dB for 'Claude' by comparing with those of the conventional pixel-based and adaptive estimation method, respectively.