• Title/Summary/Keyword: Recursive Estimation

Search Result 330, Processing Time 0.025 seconds

Double Unit Root Tests Based on Recursive Mean Adjustment and Symmetric Estimation

  • Shin, Dong-Wan;Lee, Jong-Hyup
    • Journal of the Korean Statistical Society
    • /
    • v.30 no.2
    • /
    • pp.281-290
    • /
    • 2001
  • Symmetric estimation and recursive mean adjustment are considered to construct tests for the doble unit root hypothesis for both parametric and semiparametric time series models. It is shown that simultaneous application of symmetric estimation and recursive mean adjustment yields the most powerful test. Moreover, size property of the semiparametric test based on the simultaneous application is bet among all semiparametric tests.

  • PDF

Real-time Projectile Motion Trajectory Estimation Considering Air Resistance of Obliquely Thrown Object Using Recursive Least Squares Estimation (비스듬히 던진 물체의 공기저항을 고려한 재귀 최소 자승법 기반 실시간 포물선 운동 궤적 추정)

  • Jeong, Sangyoon;Chwa, Dongkyoung
    • The Transactions of The Korean Institute of Electrical Engineers
    • /
    • v.67 no.3
    • /
    • pp.427-432
    • /
    • 2018
  • This paper uses a recursive least squares method to estimate the projectile motion trajectory of an object in real time. The equations of motion of the object are obtained considering the air resistance which occurs in the actual experiment environment. Because these equations consider air resistance, parameter estimation of nonlinear terms is required. However, nonlinear recursive least squares estimation is not suitable for estimating trajectory of projectile in that it requires a lot of computation time. Therefore, parameter estimation for real-time trajectory prediction is performed by recursive least square estimation after using Taylor series expansion to approximate nonlinear terms to polynomials. The proposed method is verified through experiments by using VICON Bonita motion capture system which can get three dimensional coordinates of projectile. The results indicate that proposed method is more accurate than linear Kalman filter method based on the equations of motion of projectile that does not consider air resistance.

Recursive approximate overdetermined ARMA spectral estimation (순환 근사 과결정 ARMA 스펙트럼 추정)

  • 이철희;이석원;양흥석
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 1987.10b
    • /
    • pp.446-450
    • /
    • 1987
  • In this paper, overdetermined method is used for high resolution spectral estimation in case of short data record length. To reduce the computational effort and to obtain recursive form of estimation algorithm, we modify data matrix to have near-Toeplitz structure. Then, new recursive algorithm is derived in the form of fast Kalman algorithm. Two stage procedure is used for the estimation of ARMA parameters. First AR parameters are estimated by using overdetermined modified Yule-walker equation, and then MA parameters are implicitly estimated by estimating numerator spectral coefficients(NS).

  • PDF

Development of a Recursive Multinomial Probit Model and its Possible Application for Innovation Studies

  • Jeong, Gicheol
    • STI Policy Review
    • /
    • v.2 no.2
    • /
    • pp.45-54
    • /
    • 2011
  • This paper develops a recursive multinomial probit model and describes its estimation method. The recursive multinomial probit model is an extension of a recursive bivariate probit model. The main difference between the two models is that a single decision among two or more alternatives can be considered in each choice equation in the proposed model. The recursive multinomial probit model is developed based on a standard framework of the multinomial probit model and a Bayesian approach with a Gibbs sampling is adopted for the estimation. The simulation exercise with artificial data sets is showed that the model performed well. Since the recursive multinomial probit model can be applied to analyze the causal relationship between discrete dependent variables with more than two outcomes, the model can play an important role in extending the methodology of the causal relationship analysis in innovation research.

A New Recursive Least-Squares Algorithm based on Matrix Pseudo Inverses (ICCAS 2003)

  • Quan, Zhonghua;Han, Soo-Hee;Kwon, Wook-Hyun
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2003.10a
    • /
    • pp.927-931
    • /
    • 2003
  • In this paper, a new Recursive Least-Squares(RLS) algorithm based on matrix pseudo-inverses is presented. The aim is to use the proposed new RLS algorithm for not only the over-determined but also the under-determined estimation problem. Compared with previous results, e.g., Jie Zhou et al., the derivation of the proposed recursive form is much easier, and the recursion form is also much simpler. Furthermore, it is shown by simulations that the proposed RLS algorithm is more efficient and numerically stable than the existing algorithms.

  • PDF

Online Estimation of Rotational Inertia of an Excavator Based on Recursive Least Squares with Multiple Forgetting

  • Oh, Kwangseok;Yi, Kyong Su;Seo, Jaho;Kim, Yongrae;Lee, Geunho
    • Journal of Drive and Control
    • /
    • v.14 no.3
    • /
    • pp.40-49
    • /
    • 2017
  • This study presents an online estimation of an excavator's rotational inertia by using recursive least square with forgetting. It is difficult to measure rotational inertia in real systems. Against this background, online estimation of rotational inertia is essential for improving safety and automation of construction equipment such as excavators because changes in inertial parameter impact dynamic characteristics. Regarding an excavator, rotational inertia for swing motion may change significantly according to working posture and digging conditions. Hence, rotational inertia estimation by predicting swing motion is critical for enhancing working safety and automation. Swing velocity and damping coefficient were used for rotational inertia estimation in this study. Updating rules are proposed for enhancing convergence performance by using the damping coefficient and forgetting factors. The proposed estimation algorithm uses three forgetting factors to estimate time-varying rotational inertia, damping coefficient, and torque with different variation rates. Rotational inertia in a typical working scenario was considered for reasonable performance evaluation. Three simulations were conducted by considering several digging conditions. Presented estimation results reveal the proposed estimation scheme is effective for estimating varying rotational inertia of the excavator.

Recursive Parameter estimation algorithm of the Probability (확률밀도함수의 축차모수추정 방법)

  • 한영열;박진수
    • Proceedings of the Korean Institute of Communication Sciences Conference
    • /
    • 1984.04a
    • /
    • pp.42-45
    • /
    • 1984
  • we propose a new parameter estimation algorithm that converge with probability one and in mean square, If the mean is the function of parameter of the probability density function. This recursive algorithm is applicable also ever the parameters we estimate are multiparameter case. And the results are shown by the computer simulation.

  • PDF

Multiuser Channel Estimation Using Robust Recursive Filters for CDMA System

  • Kim, Jang-Sub;Shin, Ho-Jin;Shin, Dong-Ryeol
    • Journal of Communications and Networks
    • /
    • v.9 no.3
    • /
    • pp.219-228
    • /
    • 2007
  • In this paper, we present a novel blind adaptive multiuser detector structure and three robust recursive filters to improve the performance in CDMA environments: Sigma point kalman filter (SPKF), particle filter (PF), and Gaussian mixture sigma point particle filter (GMSPPF). Our proposed robust recursive filters have superior performance over a conventional extended Kalman filter (EKF). The proposed multiuser detector algorithms initially use Kalman prediction form to estimated channel parameters, and unknown data symbol be predicted. Second, based on this predicted data symbol, the robust recursive filters (e.g., GMSPPF) is a refined estimation of joint multipaths and time delays. With these estimated multipaths and time delays, data symbol detection is carried out (Kalman correction form). Computer simulations show that the proposed algorithms outperform the conventional blind multiuser detector with the EKF. Also we can see it provides a more viable means for tracking time-varying amplitudes and time delays in CDMA communication systems, compared to that of the EKF for near-far ratio of 20 dB. For this reason, it is believed that the proposed channel estimators can replace well-known filter such as the EKF.

Improvement of Ultrasound Images Using Motion Estimation and Recursive Filtering (Motion Estimation과 Recursive Filtering을 사용한 초음파 동화상의 개선)

  • Song, J.S.;Lee, J.K.;Yang, Y.J.;Choi, H.J.;Oh, C.H.
    • Proceedings of the KOSOMBE Conference
    • /
    • v.1995 no.05
    • /
    • pp.123-126
    • /
    • 1995
  • The purpose of this paper is to improve ultrasound images using motion estimation and recursive filtering. Although averaging without motion correction can make image blurring, the proposed estimation method improves image SNR without motion blurring by recursively averaging images with motion correction. Computer simulation on the proposed method has been performed to improve phantom and ultrasound fish images and the results show the utility of the proposed method.

  • PDF

Recursive Bayesian Filter based Strike Velocity Estimation for Small Caliber Projectile (재귀적 베이시안 필터를 적용한 소화기탄의 충돌속도 추정 연구)

  • Kim, Jong-Hwan;Jo, Seungsik
    • Journal of the Korea Institute of Military Science and Technology
    • /
    • v.19 no.2
    • /
    • pp.177-184
    • /
    • 2016
  • This paper presents a strike velocity estimation using the recursive Bayesian filter that operates both correction and prediction models to probabilistically remove noises of sensors and accurately estimate the strike velocity during the real-time experiments. Four different types of bullets such as 5.56 mm M193, 7.62 mm M80, 5.45 mm 7N10 and 7.62 mm MSC were used to validate the proposed method. Compared to the existing method, the proposed method statistically results in higher stability of the strike velocity estimation as well as its reliability for the ballistic limit velocity computation.