• Title/Summary/Keyword: Recursive least squares

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SOx Process Simulation, Monitoring, and Pattern Classification in a Power Plant (발전소에서의 SOx 공정 모사, 모니터링 및 패턴 분류)

  • 최상욱;유창규;이인범
    • Journal of Institute of Control, Robotics and Systems
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    • v.8 no.10
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    • pp.827-832
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    • 2002
  • We propose a prediction method of the pollutant and a synchronous classification of the current state of SOx emission in the power plant. We use the auto-regressive with exogeneous (ARX) model as a predictor of SOx emission and use a radial basis function network (RBFN) as a pattem classifier. The ARX modeling scheme is implemented using recursive least squares (RLS) method to update the model parameters adaptively. The capability of SOx emission monitoring is utilized with the application of the RBFN classifier. Experimental results show that the ARX model can predict the SOx emission concentration well and ARX modeling parameters can be a good feature for the state monitoring. in addition, its validity has been verified through the power spectrum analysis. Consequently, the RBFN classifier in combination with ARX model is shown to be quite adequate for monitoring the state of SOx emission.

Autonomous Adaptive Digital Over Current Relay (계통변화를 고려한 자율 적응형 과전류 계전기)

  • 윤준석;최면송;이승재;현승호
    • The Transactions of the Korean Institute of Electrical Engineers A
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    • v.52 no.8
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    • pp.444-449
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    • 2003
  • In this paper present Autonomous Adaptive Digital Over Current Relay for distribution networks which acts autonomous setting using the short circuit impedance measured by relay of power systems. Automation of relay setting is one of the basic requirements for distribution automation, although manual relay setting is used at present. The short circuit impedance from a power source in distribution networks essential for the Autonomous Relay Setting changes frequently in distribution networks. In this paper the short circuit impedance is calculated with voltage and current measured in real time operation of digital relay using the Recursive Least Squares. A new method of digital relay setting is introduced using the the short circuit impedance and load current.

Residual Synchronization Error Elimination in OFDM Baseband Receivers

  • Hu, Xingbo;Huang, Yumei;Hong, Zhiliang
    • ETRI Journal
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    • v.29 no.5
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    • pp.596-606
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    • 2007
  • It is well known that an OFDM receiver is vulnerable to synchronization errors. Despite fine estimations used in the initial acquisition, there are still residual synchronization errors. Though these errors are very small, they severely degrade the bit error rate (BER) performance. In this paper, we propose a residual error elimination scheme for the digital OFDM baseband receiver aiming to improve the overall BER performance. Three improvements on existing schemes are made: a pilot-aided recursive algorithm for joint estimation of the residual carrier frequency and sampling time offsets; a delay-based timing error correction technique, which smoothly adjusts the incoming data stream without resampling disturbance; and a decision-directed channel gain update algorithm based on recursive least-squares criterion, which offers faster convergence and smaller error than the least-mean-squares algorithms. Simulation results show that the proposed scheme works well in the multipath channel, and its performance is close to that of an OFDM system with perfect synchronization parameters.

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Power Amplifier Linearization using the Polynomial Type Predistorter (다항식형 전치왜곡기를 이용한 전력증폭기 선형화)

  • 민이규;이상설
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.7
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    • pp.1102-1109
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    • 2001
  • This paper presents the new architecture of an adaptive predistortion linearizer using the polynomial type predistorter. In the proposed linearizer, most of the processes, including the predistortion, are performed with a digital signal processor(DSP). The recursive least squares(RLS) algorithm is employed for the optimization process to minimize the errors between the predistorter and postdistorter output signals. Simulation results demonstrate that the adjacent channel power ratio(ACPR) is improved by greater than 40 dB at the band edge with linearization. The convergence and reconvergence performance of the linearizer is also satisfactory.

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New approach method of finite difference formulas for control algorithm (제어 알고리즘 구현을 위한 새로운 미분값 유도 방법)

  • Kim, Tae-Yeop
    • Journal of IKEEE
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    • v.23 no.3
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    • pp.817-825
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    • 2019
  • Difference equation is useful for control algorithm in the microprocessor. To approximate a derivative values from sampled data, it is used the methods of forward, backward and central differences. The key of computing discrete derivative values is the finite difference coefficient. The focus of this paper is a new approach method of finite difference formula. And we apply the proposed method to the recursive least squares(RLS) algorithm.

$H_{\infty}$ Self-Tuning Control of a Flexible Link Robot with Unknown Payload (미지 부하 질량을 갖는 유연 링크 로봇의 $H_{\infty}$ 자기 동조 제어)

  • Han, Ki-Bong;Lee, Shi-Bok
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.2
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    • pp.160-168
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    • 1997
  • A $H_{\infty}$self-tuning control scheme for the tip position of a flexible link robot handling unknown loads is presented here. The scheme essentially comprises a recursive least-squares identification algorithm and $H_{\infty}$self-tunning controller. The $H_{\infty}$control low is designed to be robust to uncertain parameters and the self-tunning action provides adaption to unknown parameters. Through numerical study, the performance comparison of the $H_{\infty}$self-tuning controller with a constant gain $H_{\infty}$controller as well as a LQG self-tuning controller clearly shows its superior ability in handling load changes in quiescent states.nt states.

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Development of Speed and Precision in the Mass Measurement of Moving Object (이송 물체의 질령 측정 속도 및 정밀도 향상 모사 연구)

  • Lee, Woo Gab;Chung, Jin Wan;Kim, Kwang Pyo
    • Journal of the Korean Society for Precision Engineering
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    • v.11 no.6
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    • pp.136-142
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    • 1994
  • This study presents an algorithm and related techniques which could satisfy the important properties of check weighers and conveyor scales. The algorithm of Recursive Least Squares Regression is described for te weighing system simulated as a dynamic model of the second order. Using the model and the algorithm, model parameters and then the mass being weighed can be determined from the step input. The performance of the algorithm is illustrated in digital simulation. Discussions are extended to the development of fast converging algorithm. It turns out that the algorithm shows several desirable features suitable for microcomputer assisted real-time signal processing, which are high precision and stability in noisy environment.

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Comparison Study of Channel Estimation Algorithm for 4S Maritime Communications (4S 해상 통신을 위한 채널 추정 알고리즘 비교 연구)

  • Choi, Myeong Soo;Lee, Seong Ro
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.3
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    • pp.288-295
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    • 2013
  • In this paper, we compare the existing channel estimation technique for 4S (Ship to Ship, Ship to Shore) maritime communications under AWGN channel model, Rician fading channel model, and Rayleigh fading channel model respectively. In general, the received signal is corrupted by multipath and ISI (Inter Symbol Interference). The estimation of a time-varying multipath fading channel is a difficult task for the receiver. Its performance can be improved if an appropriate channel estimation filter is used. The simulation is performed in MATLAB. In this simulation, we use the popular estimation algorithms, LMS (Least Mean Square) and RLS (Recursive Least-Squares) are compared with respect to AWGN, Rician and Rayleigh channels.

A RLS-based Convergent Algorithm for Driving Characteristic Classification for Personalized Autonomous Driving (자율주행 개인화를 위한 순환 최소자승 기반 융합형 주행특성 구분 알고리즘)

  • Oh, Kwang-Seok
    • Journal of the Korea Convergence Society
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    • v.8 no.9
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    • pp.285-292
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    • 2017
  • This paper describes a recursive least-squares based convergent algorithm for driving characteristic classification for personalized autonomous driving. Recently, various researches on autonomous driving technology have been conducted for level 4 fully autonomous driving. In order for commercialization of the autonomous vehicle, personalized autonomous driving is required to minimize passenger's insecureness to the autonomous vehicle. To address this problem. this study proposes mathematical model that represents driving characteristics and recursive least-squares based algorithm that can estimate the defined characteristics. The actual data of two drivers has been used to derive driving characteristics and the hypothesis testing method has been used to classify two drivers. It is shown that the proposed algorithms can derive driving characteristics and classify two drivers reasonably.

An Accurate Estimation of a Modal System with Initial Conditions (ICCAS 2004)

  • Seo, In-Yong;Pearson, Allan E.
    • 제어로봇시스템학회:학술대회논문집
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    • 2004.08a
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    • pp.1694-1700
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    • 2004
  • In this paper, we propose the AWLS/MFT (Adaptive Weighed Least Squares/ Modulation Function Technique) devised by A. E. Pearson et al. for the transfer function estimation of a modal system and investigate the performance of several algorithms, the Gram matrix method, a Luenberger Observer (LO), Least Squares (LS), and Recursive Least Squares (RLS), for the estimation of initial conditions. With the benefit of the Modulation Function Technique (MFT), we can separate the estimation problem into two phases: the transfer function parameters are estimated in the first phase, and the initial conditions are estimated in the second phase. The LO method produces excellent IC estimates in the noise free case, but the other three methods show better performance in the noisy case. Finally, we compared our result with the Prony based method. In the noisy case, the AWLS and one of the three methods - Gram matrix, LS, and RLS- show better performance in the output Signal to Error Ratio (SER) aspect than the Prony based method under the same simulation conditions.

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