• 제목/요약/키워드: Least Squares Algorithm

검색결과 564건 처리시간 0.027초

ORTHOGONAL DISTANCE FITTING OF ELLIPSES

  • Kim, Ik-Sung
    • 대한수학회논문집
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    • 제17권1호
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    • pp.121-142
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    • 2002
  • We are interested in the curve fitting problems in such a way that the sum of the squares of the orthogonal distances to the given data points is minimized. Especially, the fitting an ellipse to the given data points is a problem that arises in many application areas, e.g. computer graphics, coordinate metrology, etc. In [1] the problem of fitting ellipses was considered and numerically solved with general purpose methods. In this paper we present another new ellipse fitting algorithm. Our algorithm if mainly based on the steepest descent procedure with the view of ensuring the convergence of the corresponding quadratic function Q(u) to a local minimum. Numerical examples are given.

정규화 혼합 Norm을 이용한 다중 채널 영상 복원 방식 (A Regularized Mixed Norm Multi-Channel Image Restoration Algorithm)

  • 홍민철;신요안;이원철
    • 한국통신학회논문지
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    • 제29권2C호
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    • pp.272-282
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    • 2004
  • 본 논문에서는 정규화 혼합 norm을 이용한 다중 채널 영상 복원 기법을 제안한다. 채널 영상 간 및 채널 영상내의 결정론적 정보를 이용한 다중 채널 영상 복원에 관한 문제를 고려한다. 제안 방식에서는 각 채널 영상에 대해 LMS (Least Mean Square) 및 LMF (Least Mean Fourth) 및 완화 함수를 결합시킨 부가 함수가 제안된다. 더불어, LMS 및 LMF의 상대적 기여도를 제한하기 위한 혼합 norm 매개 변수 및 완화 함수의 중요성을 제어하는 정규화 매개 변수는 반복 영상으로부터 예측된 각 채널의 노이즈 분포에 의해 결정되어 진다. 제안된 방식은 각 채널 영상의 첨부 노이즈 형태에 대한 사전 정보 없이 복원 과정이 가능하다는 점과 두 매개 변수를 반복 과정에서 부분적으로 복원된 영상으로부터 조절할 수 있는 특성을 갖고 있다.

An Innovative Application Method of Monthly Load Forecasting for Smart IEDs

  • Choi, Myeon-Song;Xiang, Ling;Lee, Seung-Jae;Kim, Tae-Wan
    • Journal of Electrical Engineering and Technology
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    • 제8권5호
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    • pp.984-990
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    • 2013
  • This paper develops a new Intelligent Electronic Device (IED), and then presents an application method of a monthly load forecasting algorithm on the smart IEDs. A Multiple Linear Regression (MLR) model implemented with Recursive Least Square (RLS) estimation is established in the algorithm. Case Study proves the accuracy and reliability of this algorithm and demonstrates the practical meanings through designed screens. The application method shows the general way to make use of IED's smart characteristics and thereby reveals a broad prospect of smart function realization in application.

DWMT 데이타 전송을 위한 효율적인 시간영역 등화기 설계 (Efficient time domain equalizer design for DWMT data transmission)

  • 홍훈희;박태윤;유승선;곽훈성;최재호
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 1999년도 하계종합학술대회 논문집
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    • pp.69-72
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    • 1999
  • In this paper, an efficient time domain equalization algorithm for discrete wavelet multitone(DWMT) data transmission is developed. In this algorithm, the time domain equalizer(TEQ) consists of two stages, i.e., the channel impulse response shortening equalizer(TEQ-S) in the first stage and the channel frequency flattening equalizer(TEQ-F) in the second stage. TEQ-S reduces the length of transmission channel impulse response to decrease intersymbol interference(ISI) followed by TEQ-F that enhances the channel frequency response characteristics to the level of an ideal channel, hence diminishes the bit error rate. TEQ-S is implemented using the least-squares(LS) method, while TEQ-F is designed by using the least mean-square(LMS) algorithm. Since DWMT system also requires of the frequency domain equalizer in order to further reduce ICI and ISI the hardware complexity is an another concern. However, by adopting an well designed and trained TEQ, the hardware complexity of the whole DWMT system can be greatly reduced.

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자율주행 버스의 종방향 제어를 위한 질량 및 종 경사 추정기 개발 (Vehicle Mass and Road Grade Estimation for Longitudinal Acceleration Controller of an Automated Bus)

  • 조아라;정용환;임형호;이경수
    • 자동차안전학회지
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    • 제12권2호
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    • pp.14-20
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    • 2020
  • This paper presents a vehicle mass and road grade estimator for developing an automated bus. To consider the dynamic characteristics of a bus varying with the number of passengers, the longitudinal controller needs the estimation of the vehicle's mass and road grade in real-time and utilizes the information to adjust the control gains. Discrete Kalman filter is applied to estimate the time-varying road grade, and the recursive least squares algorithm is adopted to account for the constant mass estimation. After being implemented in MATLAB/Simulink, the estimators are evaluated with the dynamic model and experimental data of the target bus. The proposed estimators will be applied to complement the algorithm of the longitudinal controller and proceed with algorithm verification.

Nonlinear structural system wind load input estimation using the extended inverse method

  • Lee, Ming-Hui
    • Wind and Structures
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    • 제17권4호
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    • pp.451-464
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    • 2013
  • This study develops an extended inverse input estimation algorithm with intelligent adaptive fuzzy weighting to effectively estimate the unknown input wind load of nonlinear structural systems. This algorithm combines the extended Kalman filter and recursive least squares estimator with intelligent adaptive fuzzy weighting. This study investigated the unknown input wind load applied on a tower structural system. Nonlinear characteristics will exist in various structural systems. The nonlinear characteristics are particularly more obvious when applying larger input wind load. Numerical simulation cases involving different input wind load types are studied in this paper. The simulation results verify the nonlinear characteristics of the structural system. This algorithm is effective in estimating unknown input wind loads.

적응 신호 처리를 위한 고속 선형 위상 FIR 필터 (Fast linear-phase FIR filter for adaptive signal processing)

  • 최승진;이철희;양홍석
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.172-177
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    • 1988
  • In this paper, a new fast algorithm of FIR least squares filter with linear phase is presented. The general unknown statistics case is considered, whereby only sample records of the data are available. Taking advantage of the near-to-Toeplitz+Hankel structure of the resulting normal equation, a fast algorithm which gurantees the linear phase constraint, is developed that recursively produces the filter coefficient of linear phase FIR filter for a single block of data.

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TWO DIMENSIONAL VERSION OF LEAST SQUARES METHOD FOR DEBLURRING PROBLEMS

  • Kwon, SunJoo;Oh, SeYoung
    • 충청수학회지
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    • 제24권4호
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    • pp.895-903
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    • 2011
  • A two dimensional version of LSQR iterative algorithm which takes advantages of working solely with the 2-dimensional arrays is developed and applied to the image deblurring problem. The efficiency of the method comparing to the Fourier-based LSQR method and the 2-D version CGLS algorithm methods proposed by Hanson ([4]) is analyzed.

A Robust Estimator in Multivariate Regression Using Least Quartile Difference

  • Jung Kang-Mo
    • Communications for Statistical Applications and Methods
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    • 제12권1호
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    • pp.39-46
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    • 2005
  • We propose an equivariant and robust estimator in multivariate regression model based on the least quartile difference (LQD) estimator in univariate regression. We call this estimator as the multivariate least quartile difference (MLQD) estimator. The MLQD estimator considers correlations among response variables and it can be shown that the proposed estimator has the appropriate equivariance properties defined in multivariate regressions. The MLQD estimator has high breakdown point as does the univariate LQD estimator. We develop an algorithm for MLQD estimate. Simulations are performed to compare the efficiencies of MLQD estimate with coordinatewise LQD estimate and the multivariate least trimmed squares estimate.

Identification of Fuzzy Inference Systems Using a Multi-objective Space Search Algorithm and Information Granulation

  • Huang, Wei;Oh, Sung-Kwun;Ding, Lixin;Kim, Hyun-Ki;Joo, Su-Chong
    • Journal of Electrical Engineering and Technology
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    • 제6권6호
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    • pp.853-866
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    • 2011
  • We propose a multi-objective space search algorithm (MSSA) and introduce the identification of fuzzy inference systems based on the MSSA and information granulation (IG). The MSSA is a multi-objective optimization algorithm whose search method is associated with the analysis of the solution space. The multi-objective mechanism of MSSA is realized using a non-dominated sorting-based multi-objective strategy. In the identification of the fuzzy inference system, the MSSA is exploited to carry out parametric optimization of the fuzzy model and to achieve its structural optimization. The granulation of information is attained using the C-Means clustering algorithm. The overall optimization of fuzzy inference systems comes in the form of two identification mechanisms: structure identification (such as the number of input variables to be used, a specific subset of input variables, the number of membership functions, and the polynomial type) and parameter identification (viz. the apexes of membership function). The structure identification is developed by the MSSA and C-Means, whereas the parameter identification is realized via the MSSA and least squares method. The evaluation of the performance of the proposed model was conducted using three representative numerical examples such as gas furnace, NOx emission process data, and Mackey-Glass time series. The proposed model was also compared with the quality of some "conventional" fuzzy models encountered in the literature.