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Wyszukujesz frazę "adaptive estimation" wg kryterium: Temat


Tytuł:
Adaptive trimmed likelihood estimation in regression
Autorzy:
Bednarski, Tadeusz
Clarke, Brenton
Schubert, Daniel
Powiązania:
https://bibliotekanauki.pl/articles/729910.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
trimmed likelihood estimator
adaptive estimation
regression
Opis:
In this paper we derive an asymptotic normality result for an adaptive trimmed likelihood estimator of regression starting from initial high breakdownpoint robust regression estimates. The approach leads to quickly and easily computed robust and efficient estimates for regression. A highlight of the method is that it tends automatically in one algorithm to expose the outliers and give least squares estimates with the outliers removed. The idea is to begin with a rapidly computed consistent robust estimator such as the least median of squares (LMS) or least trimmed squares (LTS) or for example the more recent MM estimators of Yohai. Such estimators are now standard in statistics computing packages, for example as in SPLUS or R. In addition to the asymptotics we provide data analyses supporting the new adaptive approach. This approach appears to work well on a number of data sets and is quicker than the related brute force adaptive regression approach described in Clarke (2000). This current approach builds on the work of Bednarski and Clarke (2002) which considered the asymptotics for the location estimator only.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2010, 30, 2; 203-219
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Some inferential questions in regard to analysing two-way Layouts and associated linear model theory and practice
Autorzy:
Clarke, Brenton
Monaco, Antony
Powiązania:
https://bibliotekanauki.pl/articles/729772.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Wydział Matematyki, Informatyki i Ekonometrii
Tematy:
outlier
two-way layout
adaptive estimation
heteroscedaticity
Opis:
In analysing a well known data set from the literature which can be thought of as a two-way layout it transpires that a robust adaptive regression approach for identifying outliers fails to be sensitive enough to detect the possible interchange of two observations. On the other hand if one takes the classical approach of diagnostic checking one may also stop too early and be satisfied with a model that falls short of a more detailed analysis that takes account of heteroscedasticity in the data. An exact F-test for heteroscedasticity in the two way layout is compared with various more general tests proposed by Shukla. In conclusion it is noted that when modelling the particular form of heteroscedasticity countenanced here, the estimated column effects are unchanged from those estimated from the model assuming homogeneous error variance structure. It is only the estimated variances of these column effects that changes.
Źródło:
Discussiones Mathematicae Probability and Statistics; 2004, 24, 2; 183-195
1509-9423
Pojawia się w:
Discussiones Mathematicae Probability and Statistics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Influence of Drift on Efficiency of Optimal Analog Adaptive Communication Systems with Feedback and Its Compensation
Autorzy:
Jędrzejewski, K.
Powiązania:
https://bibliotekanauki.pl/articles/227312.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
communication systems
feedback
drift compensation
optimal adaptive estimation
Opis:
Results of analysis of drift influence on operation and efficiency of optimal analog adaptive communication systems with feedback and a new approach to drift compensation in these systems are presented in the paper. The proposed approach is based on application of the extended multidimensional adaptive algorithm that estimates simultaneously the value of a transmitted sample and the value of an unknown drift rate. The knowledge of the drift rate enables drift compensation and improves transmission efficiency of systems suffering problems related to drifts.
Źródło:
International Journal of Electronics and Telecommunications; 2013, 59, 1; 51-58
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The look-up algorithm of monitoring an object described by non-linear ordinary differential equations
Autorzy:
Hawro, Przemysław
Kwater, Tadeusz
Bartman, Jacek
Kwiatkowski, Bogdan
Powiązania:
https://bibliotekanauki.pl/articles/2204529.pdf
Data publikacji:
2023
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adaptive estimation
polluted river
MATLAB
lookup algorithm
monitoring online
algorytm wyszukiwania
monitorowanie on-line
zanieczyszczenie rzeki
szacowanie adaptacyjne
Opis:
The article proposes an adaptive algorithm that generates all object signals, including those for which measurements are not performed due to the difficulties associated with on-line measurements. The algorithm is modeled on the idea of the Kalman filter using its equation, however, the selection of gains is optimized in a different way, i.e. the constant values depend on the adopted ranges of adaptation errors. Moreover, the knowledge of the statistics of all noise signals is not imposed and there is no linearity constraint. This approach allowed to reduce the complexity of calculations. This algorithm can be used in real-time systems to generate signals of objects described by non-linear differential equations and it is universal, which allows it to be used for various objects. In the conducted research, on the example of a biochemically contaminated river, only easily measurable signals were used to generated the object signals, and in addition, in the case of absence some measurements, the functioning of the algorithm did not destabilize.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2023, 71, 2; art. no. e144603
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Observer-based fault estimation for linear systems with distributed time delay
Autorzy:
Filasova, A.
Gontkovič, D.
Krokavec, D.
Powiązania:
https://bibliotekanauki.pl/articles/229173.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adaptive fault estimation
distributed time delay systems
Lyapunov-Krasovskii functional
integral partitioning technique
time delay segmentation
linear matrix inequalities
Opis:
The paper is engaged with the framework of designing adaptive fault estimation for linear continuous-time systems with distributed time delay. The Lyapunov-Krasovskii functional principle is enforced by imposing the integral partitioning method and a new equivalent delaydependent design condition for observer-based assessment of faults are established in terms of linear matrix inequalities. Asymptotic stability conditions are derived and regarded with respect to the incidence of structured matrix variables in the linear matrix inequality formulation. Simulation results illustrate the design approach, and demonstrates power and performance of the actuator fault assessment.
Źródło:
Archives of Control Sciences; 2013, 23, 2; 169-186
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On adaptive control of Markov chains using nonparametric estimation
Autorzy:
Drabik, Ewa
Stettner, Łukasz
Powiązania:
https://bibliotekanauki.pl/articles/1208175.pdf
Data publikacji:
2000
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
controlled Markov chain
estimation
adaptive control
Opis:
Two adaptive procedures for controlled Markov chains which are based on a nonparametric window estimation are shown.
Źródło:
Applicationes Mathematicae; 2000, 27, 2; 143-152
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Asymptotically stable estimators of location and scale parameters II. Estimation of scale parameter
Autorzy:
Rychlik, Tomasz
Powiązania:
https://bibliotekanauki.pl/articles/747721.pdf
Data publikacji:
1987
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Robustness and adaptive procedures
Point estimation
Opis:
.
Asymptotic robustness of estimators of scale parameter with respect to scale invariant bias oscillation function is studied for two types of disturbances. In the case of £-contamination, the most robust sequence of equivariant estimators for model distribution with a positive support and the most robust sequence of equivariant symmetric estimators for symmetric model distribution are constructed. In the case of Kolmogorov-Levy neighbourhoods, the solution is derived without any assumptions about the model distribution. As examples, the most bias-robust estimators for uniform, Pareto, Weibull, Laplace, normal, Cauchy and double-exponential distributions are presented.
Źródło:
Mathematica Applicanda; 1987, 16, 30
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The "jackknife" method
Autorzy:
Bieńkiewicz, Małgorzta
Powiązania:
https://bibliotekanauki.pl/articles/747860.pdf
Data publikacji:
1982
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Point estimation
Instructional exposition
Robustness and adaptive procedures
Opis:
.
A short review paper which explains the idea of jackknifing to those who have never heard about it.
Źródło:
Mathematica Applicanda; 1982, 10, 21
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The algorithm of adaptive determination of amplification of the PD filter estimating object state on the basis of signal measurable on-line
Autorzy:
Kwater, Tadeusz
Hawro, Przemysław
Bartman, Jacek
Mazur, Damian
Powiązania:
https://bibliotekanauki.pl/articles/1409165.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
estimation
Kalman filter
adaptive PD filter
filter amplification
Opis:
The article presents the algorithm that enables adaptive determination of the amplification coefficient in the filter equation provided by Kalman. The method makes use of an estimation error, which was defined for this purpose, and its derivative to determine the direction of correction changes of the gain vector. This eliminates the necessity to solve Riccati equation, which causes reduction of the method computational complexity. The experimental studies carried out using the proposed approach relate to the estimation of state coordinates describing river pollution using the BOD (biochemical oxygen demand) and DO (dissolved oxygen) indicators).The acquired results indicate that the suggested method does better estimations than the Kalman filter. Two indicators were used to measure the quality of estimates: the Root Mean Squared Error (RMSE) and the Mean Percentage Error (MPE).
Źródło:
Archives of Control Sciences; 2021, 31, 1; 129-143
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adaptive Control of Discrete Time-Varying LQGko
Autorzy:
Czornik, Adam
Powiązania:
https://bibliotekanauki.pl/articles/748156.pdf
Data publikacji:
1999
Wydawca:
Polskie Towarzystwo Matematyczne
Tematy:
Estimation and detection
Adaptive control
Discrete-time systems
Stochastic learning and adaptive control
Opis:
.
The adaptive version of the discrete time-varying linear quadratic control is considered under the assumption that the coefficients have limits as time tends to infinity sufficiently fast in certain sense and the limiting system is observable and stabilizable. It is proved that time invariant LS estimator can be used to estimate the limits of the coefficients and that it is strongly consistent under some conditions well known from the time invariant case. The estimator of the parameters is used to define an adaptive control law and it is shown that the control law is optimal.
Źródło:
Mathematica Applicanda; 1999, 27, 41
1730-2668
2299-4009
Pojawia się w:
Mathematica Applicanda
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Fuzzy adaptive Kalman filter for the drive system with an elastic coupling
Autorzy:
Serkies, P. J.
Szabat, K.
Powiązania:
https://bibliotekanauki.pl/articles/140962.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adaptive KF
two-mass drive
fuzzy logic
robust estimation
Opis:
In the paper issues related to the design of a robust adaptive fuzzy estimator for a drive system with a flexible joint is presented. The proposed estimator ensures variable Kalman gain (based on the Mahalanobis distance) as well as the estimation of the system parameters (based on the fuzzy system). The obtained value of the time constant of the load machine is used to change the values in the system state matrix and to retune the parameters of the state controller. The proposed control structure (fuzzy Kalman filter and adaptive state controller) is investigated in simulation and experimental tests.
Źródło:
Archives of Electrical Engineering; 2013, 62, 2; 251-265
1427-4221
2300-2506
Pojawia się w:
Archives of Electrical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Nonadaptive estimation of the rotor speed in an adaptive full order observer of induction machine
Autorzy:
Morawiec, M.
Kroplewski, P.
Powiązania:
https://bibliotekanauki.pl/articles/202062.pdf
Data publikacji:
2020
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
observers
induction machines
speed estimation
adaptive full order observer
Opis:
The article proposes a new method of reproducing the angular speed of the rotor of a cage induction machine designed for speed observers based on the adaptive method. In the proposed solution, the value of the angular speed of the rotor is not determined by the classical law of adaptation using the integrator only by an algebraic relationship. Theoretical considerations were confirmed by simulation and experimental tests.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2020, 68, 5; 973--981
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
GOP Structure Adaptable to the Location of Shot Cuts
Autorzy:
Krulikovská, L.
Polec, J.
Powiązania:
https://bibliotekanauki.pl/articles/227351.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
shot cut detection
Pearson correlation coefficient
motion estimation
adaptive threshold
video encoding
adaptive GOP structure
Opis:
In this paper we present a novel two stage algorithm for improving video coding efficiency. The proposed method combines video cut detection and adaptive GOP structure. At first, we have proposed a new technique of frames' comparison for the shot cut detection. The majority of existing methods compare pairs of successive frames. We compare actual frame with its motion estimated prediction. We also present adaptive threshold. The efficiency of novel technique for video cut detection was confirmed through experiment and compared to the commonly used ones in the terms of recall and precision. The next step is to situate I frames to the positions of detected cuts during the process of video encoding. Finally the proposed method is verified by simulations and the obtained results are compared with fixed GOP structures of sizes 4, 8, 12, 16, 32, 64, 128 and GOP structure with length of entire video. Proposed method achieved the gain in bit rate from 15,33% to 50,59%, while not degrading PSNR in comparison to simulated fixed GOP structures.
Źródło:
International Journal of Electronics and Telecommunications; 2012, 58, 2; 129-134
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
RADAR Signal Parameters Estimation in the MTD Tasks
Autorzy:
Prokopenko, I. G.
Omelchuk, I. P.
Chyrka, Y. D.
Powiązania:
https://bibliotekanauki.pl/articles/227274.pdf
Data publikacji:
2012
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
radar
detection
moving targets
frequency estimation
adaptive algorithms
Bayesian empirical approach
Opis:
The MTD method adaptive to current target speed, in which suboptimal iterative algorithms for the reflected signal parameters estimation are synthesized, is suggested. This method allows to detect a slowly moving targets with radial speed 3-4 times less, than for pulse-pair subtraction (PPS).
Źródło:
International Journal of Electronics and Telecommunications; 2012, 58, 2; 159-164
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Optimized grid structures for the characteristic diagram based estimation of thermo-elastic tool center point displacements in machine tools
Autorzy:
Putz, M.
Ihlenfeldt, S.
Naumann, C.
Glänzel, J.
Powiązania:
https://bibliotekanauki.pl/articles/100061.pdf
Data publikacji:
2017
Wydawca:
Wrocławska Rada Federacji Stowarzyszeń Naukowo-Technicznych
Tematy:
characteristic diagram
adaptive structured grids
thermoelastic deformation
grid optimization
thermal error estimation
Opis:
It is a well-known problem of milling machines, that waste heat from motors, friction effects on guides and also the milling process itself greatly affect the positioning accuracy and thus the production quality. An economic and energy-efficient method of correcting this thermo-elastic positioning error is to gather sensor data from the machine tool and the process and to use that information to predict and correct the resulting tool center point displacement using high dimensional characteristic diagrams. The size of these characteristic diagrams depends on the number of input variables (sensors) and the fineness of the discretization of the grid. While the number of sensors can usually not be reduced without affecting the quality of the prediction, it is often possible to minimize the size of characteristic diagrams through the use of adaptive grid refinement. This ensures that the finest grid sections correspond with the load cases that have the largest local gradients. Through such adaptive refinement, it is possible to reduce storage capacity and computation time without significant loss of precision. The aim of this article is to examine, test and compare different methods of adaptive grid refinement. For this, simulation data from a machine tool is used.
Źródło:
Journal of Machine Engineering; 2017, 17, 3; 36-50
1895-7595
2391-8071
Pojawia się w:
Journal of Machine Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Bayesian parameter estimation and adaptive control of Markov processes with time-averaged cost
Autorzy:
Borkar, V.
Associate, S.
Powiązania:
https://bibliotekanauki.pl/articles/1339007.pdf
Data publikacji:
1998
Wydawca:
Polska Akademia Nauk. Instytut Matematyczny PAN
Tematy:
time-averaged cost
adaptive control
asymptotic optimality
cost-biased estimate
Bayesian estimation
Opis:
This paper considers Bayesian parameter estimation and an associated adaptive control scheme for controlled Markov chains and diffusions with time-averaged cost. Asymptotic behaviour of the posterior law of the parameter given the observed trajectory is analyzed. This analysis suggests a "cost-biased" estimation scheme and associated self-tuning adaptive control. This is shown to be asymptotically optimal in the almost sure sense.
Źródło:
Applicationes Mathematicae; 1998-1999, 25, 3; 339-358
1233-7234
Pojawia się w:
Applicationes Mathematicae
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
PCA Assisted DTCWT Denoising for Improved DOA Estimation of Closely Spaced and Coherent Signals
Autorzy:
Ganage, Dharmendra
Ravinder, Yerram
Powiązania:
https://bibliotekanauki.pl/articles/226634.pdf
Data publikacji:
2019
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
DOA estimation
signal denoising
closely spaced
coherent signal
adaptive antenna array
antenna elements
Opis:
Performance of standard Direction of Arrival (DOA) estimation techniques degraded under real-time signal conditions. The classical algorithms are Multiple Signal Classification (MUSIC), and Estimation of Signal Parameters via Rotational Invariance Technique (ESPRIT). There are many signal conditions hamper on its performance, such as closely spaced and coherent signals caused due to the multipath propagations of signals results in a decrease of the signal to noise ratio (SNR) of the received signal. In this paper, a novel DOA estimation technique named CW-PCA MUSIC is proposed using Principal Component Analysis (PCA) to threshold the nearby correlated wavelet coefficients of Dual-Tree Complex Wavelet transform (DTCWT) for denoising the signals before applying to MUSIC algorithm. The proposed technique improves the detection performance under closely spaced, and coherent signals with relatively low SNR conditions. Also, this method requires fewer snapshots, and less antenna array elements compared with standard MUSIC and wavelet-based DOA estimation algorithms.
Źródło:
International Journal of Electronics and Telecommunications; 2019, 65, 1; 111-117
2300-1933
Pojawia się w:
International Journal of Electronics and Telecommunications
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Remaining useful life prediction of cylinder liner based on nonlinear degradation model
Autorzy:
Kang, Jianxiong
Lu, Yanjun
Zhao, Bin
Luo, Hongbo
Meng, Jiacheng
Zhang, Yongfang
Powiązania:
https://bibliotekanauki.pl/articles/2057982.pdf
Data publikacji:
2022
Wydawca:
Polska Akademia Nauk. Polskie Naukowo-Techniczne Towarzystwo Eksploatacyjne PAN
Tematy:
remaining useful life
cylinder liner wear
nonlinear degradation
maximum likelihood estimation
adaptive PDF
Opis:
In order to effectively monitor the wear and predict the life of cylinder liner, a nonlinear degradation model with multi-source uncertainty based on Wiener process is established to evaluate the remaining useful life (RUL) of cylinder liner wear. Due to complex service performance of cylinder liner, the uncertainty of operational environment and working conditions of cylinder liner wear are considered into the model by a random function. The probability density function (PDF) formula of RUL is derived, and the maximum likelihood estimation method is adopted to estimate the unknown parameters of PDF. Considering the evaluated parameters as the initial values, the model parameters are updated adaptively, and an adaptive PDF is obtained. Furthermore, the proposed model is compared with two classical degradation models. The results show that the proposed model has a good performance for predicting the life, and the error is within 5%. The method can provide a reference for condition monitoring of cylinder liner wear.
Źródło:
Eksploatacja i Niezawodność; 2022, 24, 1; 62--69
1507-2711
Pojawia się w:
Eksploatacja i Niezawodność
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Adaptive observer-based fault estimation for a class of Lipschitz nonlinear systems
Autorzy:
Oucief, N.
Tadjine, M.
Labiod, S.
Powiązania:
https://bibliotekanauki.pl/articles/229517.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
nonlinear adaptive observer
fault estimation
strictly positive real
Lipschitz systems
observer matching condition
LMI
Opis:
Fault input channels represent a major challenge for observer design for fault estimation. Most works in this field assume that faults enter in such a way that the transfer functions between these faults and a number of measured outputs are strictly positive real (SPR), that is, the observer matching condition is satisfied. This paper presents a systematic approach to adaptive observer design for joint estimation of the state and faults when the SPR requirement is not verified. The proposed method deals with a class of Lipschitz nonlinear systems subjected to piecewise constant multiplicative faults. The novelty of the proposed approach is that it uses a rank condition similar to the observer matching condition to construct the adaptation law used to obtain fault estimates. The problem of finding the adaptive observer matrices is formulated as a Linear Matrix Inequality (LMI) optimization problem. The proposed scheme is tested on the nonlinear model of a single link flexible joint robot system.
Źródło:
Archives of Control Sciences; 2016, 26, 2; 245-259
1230-2384
Pojawia się w:
Archives of Control Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A very-low-speed sensorless control induction motor drive with online rotor resistance tuning by using MRAS scheme
Autorzy:
Agrebi Zorgani, Y.
Jouili, M.
Koubaa, Y.
Boussak, M.
Powiązania:
https://bibliotekanauki.pl/articles/1193675.pdf
Data publikacji:
2018
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
induction motor
stator flux orientation model
model reference adaptive system
MRAS
rotor speed estimation
resistance estimation
programmable cascaded low-pass filters
PCLPF
Opis:
A sensorless indirect stator-flux-oriented control (ISFOC) induction motor drive at very low frequencies is presented herein. The model reference adaptive system (MRAS) scheme is used to estimate the speed and the rotor resistance simultaneously. However, the error between the reference and the adjustable models, which are developed in the stationary stator reference frame, is used to drive a suitable adaptation mechanism that generates the estimates of speed and the rotor resistance from the stator voltage and the machine current measurements. The stator flux components in the stationary reference frame are estimated through a pure integration of the back electro-motive force (EMF) of the machine. When the machine is operated at low speed, the pure integration of the back EMF introduces an error in flux estimation which affects the performance torque and speed control. To overcome this problem, pure integration is replaced with a programmable cascaded low-pass filter (PCLPF). The stability analysis method of the MRAS estimator is verified in order to show the robustness of the rotor resistance variations. Experimental results are presented to prove the effectiveness and validity of the proposed scheme of sensorless ISFOC induction motor drive.
Źródło:
Power Electronics and Drives; 2018, 3, 38; 171-186
2451-0262
2543-4292
Pojawia się w:
Power Electronics and Drives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A Very-Low-Speed Sensorless Control Induction Motor Drive with Online Rotor Resistance Tuning by Using MRAS Scheme
Autorzy:
Zorgani, Youssef Agrebi
Jouili, Mabrouk
Koubaa, Yassine
Boussak, Mohamed
Powiązania:
https://bibliotekanauki.pl/articles/1193692.pdf
Data publikacji:
2019
Wydawca:
Politechnika Wrocławska. Oficyna Wydawnicza Politechniki Wrocławskiej
Tematy:
induction motor
stator flux orientation model
model reference adaptive system
MRAS
rotor speed estimation
resistance estimation
programmable cascaded low-pass filters
PCLPF
Opis:
A sensorless indirect stator-flux-oriented control (ISFOC) induction motor drive at very low frequencies is presented herein. The model reference adaptive system (MRAS) scheme is used to estimate the speed and the rotor resistance simultaneously. However, the error between the reference and the adjustable models, which are developed in the stationary stator reference frame, is used to drive a suitable adaptation mechanism that generates the estimates of speed and the rotor resistance from the stator voltage and the machine current measurements. The stator flux components in the stationary reference frame are estimated through a pure integration of the back electro-motive force (EMF) of the machine. When the machine is operated at low speed, the pure integration of the back EMF introduces an error in flux estimation which affects the performance torque and speed control. To overcome this problem, pure integration is replaced with a programmable cascaded low-pass filter (PCLPF). The stability analysis method of the MRAS estimator is verified in order to show the robustness of the rotor resistance variations. Experimental results are presented to prove the effectiveness and validity of the proposed scheme of sensorless ISFOC induction motor drive.
Źródło:
Power Electronics and Drives; 2019, 4, 39; 125-140
2451-0262
2543-4292
Pojawia się w:
Power Electronics and Drives
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unified approach to the sliding-mode control and state estimation – application to the induction motor drive
Autorzy:
Orlowska-Kowalska, T.
Tarchala, G.
Powiązania:
https://bibliotekanauki.pl/articles/201791.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
induction motor
sliding mode control
motor torque control
chattering
state estimation
model reference adaptive system (MRAS)
Opis:
In this paper a generalized design procedure of the sliding mode systems is described. A unified approach is applied to control and state variables estimation algorithms. Selected solutions are then applied in the induction motor drive system. An identical design procedure is used to design the speed control and MRAS-type speed estimator. Presented algorithms are verified using experimental tests performed on the 3 kW laboratory setup.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2013, 61, 4; 837-846
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
SAMEE : the nonlinear adaptive method for predicting work effort of information systems development
SAMEE : nieliniowa adaptacyjna metoda predykcji pracochłonności wytworzenia systemów informatycznych
Autorzy:
Augustyn, D.
Warchal, L.
Powiązania:
https://bibliotekanauki.pl/articles/375691.pdf
Data publikacji:
2013
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
adaptive method for work effort prediction
polynomial estimation model
software analysis and design
Enterprise Architect add-in
Opis:
At the early stage of information system analysis and design one of the challenge is to estimate total work effort needed, when only small number of analysis artifacts is available. As a solution we propose new method called SAMEE – Simple Adaptive Method for Effort Estimation. It is based on the idea of polynomial regression and uses selected UML artifacts like use cases, actors, domain classes and references between them. In this paper we describe implementation of this method in Enterprise Architect CASE tool and show simple example how to use it in real information system analysis.
We wczesnych etapach tworzenia systemu informatycznego szczególnie trudnym zadaniem jest wstępne oszacowanie pracochłonności wytworzenia całego systemu, gdy pierwszy, wstępny, analityczny opis systemu jest znikomy, tzn. gdy dostępne są jednie uproszczone artefakty analityczne (w sensie dostępności tylko niektórych rodzajów artefaktów i niskiej szczegółowości ich opisu). W niniejszym artykule zaproponowano metodę SAMEE (ang. Simple Adaptive Method for Effort Estimation), tzn. prostą adaptacyjną metodę szacowania pracochłonności, opartą na UML-owych artefaktach analitycznych takich jak: cechy systemu, przypadki użycia aktorzy, klasy dziedzinowe, referencje pomiędzy klasami. Na podstawie znajomości danych historycznych dotyczących pracochłonności realizacji cech oraz związanych z tymi cechami artefaktami (przypadki użycia, aktorzy, klasy, referencje) metoda określa nieliniowy model estymacji pracochłonności wytworzenia cech. Wykorzystując regresję wielomianową, metoda pozwala na znalezienie jawnej zależności pomiędzy pracochłonnością wytworzenia cech systemu, a innymi, wymienionymi wcześniej artefaktami. W szczególności metoda pozwala na wskazanie, który typ artefaktu ma najistotniejszy wpływ na estymowane pracochłonności cech. Metoda ma charakter adaptacyjny i lokalny, tzn. uzyskany model wynikowy zależny jest ściśle od organizacji procesu wytwórczego, zespołu produkcyjnego, przyjętych narzędzi wytwórczych. Artykuł opisuje również prototypową implementację metody SAMEE w postaci tzw. programowej wtyczki (ang.plug-in) do popularnego narzędzia CASE – Enterprise Architect – wspomagającego analizę i projektowanie systemów informatycznych. Dodatkowo, dzięki mechanizmowy profi li UML, odpowiednie artefakty (np. cechy) zostały wzbogacone o atrybuty wymagane do obsługi zaproponowanej metody estymacji. Taka integracja z narzędziem CASE pozwala myśleć o praktycznym zastosowaniu narzędzia do szacowania pracochłonności metodą SAMEE. Przykład konkretnego użycia SAMEE w narzędziu Enterprise Architect został zamieszczony w opracowaniu. W artykule opisano również potencjalne kierunki rozwoju metody (np. zastosowanie szerszej bazy typów artefaktów analitycznych, czy wykorzystanie innego, bardziej złożonego, nieliniowego modelu estymacji).
Źródło:
Theoretical and Applied Informatics; 2013, 25, 1; 3-15
1896-5334
Pojawia się w:
Theoretical and Applied Informatics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An adaptive observer design approach for a class of discrete-time nonlinear systems
Autorzy:
Srinivasarengan, K.
Ragot, J.
Aubrun, C.
Maquin, D.
Powiązania:
https://bibliotekanauki.pl/articles/330844.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
adaptive observer
joint state estimation
parameter estimation
Takagi-Sugeno model
time-varying parameter estimation
sector nonlinearity transformation
discrete-time nonlinear systems
obserwator adaptacyjny
identyfikacja parametrów
model Takagi-Sugeno
transformacja nieliniowa
dyskretny układ nieliniowy
Opis:
We consider the problem of joint estimation of states and some constant parameters for a class of nonlinear discrete-time systems. This class contains systems that could be transformed into a quasi-LPV (linear parameter varying) polytopic model in the Takagi–Sugeno (T–S) form. Such systems could have unmeasured premise variables, a case usually overlooked in the observer design literature. We assert that, for such systems in discrete-time, the current literature lacks design strategies for joint state and parameter estimation. To this end, we adapt the existing literature on continuous-time linear systems for joint state and time-varying parameter estimation. We first develop the discrete-time version of this result for linear systems. A Lyapunov approach is used to illustrate stability, and bounds for the estimation error are obtained via the bounded real lemma. We use this result to achieve our objective for a design procedure for a class of nonlinear systems with constant parameters. This results in less conservative conditions and a simplified design procedure. A basic waste water treatment plant simulation example is discussed to illustrate the design procedure.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2018, 28, 1; 55-67
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On possibilities of the practical implementation of balance-based adaptive control methodology
Autorzy:
Czeczot, J.
Powiązania:
https://bibliotekanauki.pl/articles/1839191.pdf
Data publikacji:
2007
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
model-based adaptive control
practical implementation
bumpless switching
virtual controllers
programmable logic controller (PLC)
recursive least-squares estimation
Opis:
This paper deals with two approaches to the practical implementation of the Balance-Based Adaptive Controller(B-BAC): the low-level PLC-based approach of the explicit form of the B-BAC and the high-level PC-based one in the form of the general "virtual controller". In both cases, we discuss the details of meeting the general requirements of a particular practical implementation. We also consider the implementation aspects that are independent of the implementation, such as development of the front panel, saturation of a manipulated variable, on-line measurement and data acquisition, implementation of the on-line estimation procedure, bumpless switching between the automatic and manual mode, etc. Additionally, we present how to derive both the general form and the final explicit form of the B-BAC on the example of a biotechnological process and how to apply these forms in the particular practical implementation.
Źródło:
Control and Cybernetics; 2007, 36, 4; 967-984
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł

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