Wyniki wyszukiwania - BazTech

1

Testing the SDC memristors in three phase systems

Garda Bartłomiej, Bednarz Karol

Przegląd Elektrotechniczny

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2025

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R. 101, nr 2

52--55

EN

The objective outlined in the paper is to conduct reliable measurement tests on memristor behavior in three-phase systems. Memristors, acting as nonlinear elements, exhibit intriguing phenomena within such systems. Various configurations, including Delta and Wye connections with three and four wires, have been tested. The collected data has been analyzed and presented, with additional frequency analysis using FFT and assessment of total harmonic distortion factors. The acquired data has been modelled using the MMS memristor model and compared with the actual data.

PL

W artykule przedstawiono wyniki testów pomiarowych opisujących zachowania memrystorów w systemach trójfazowych. Memrystory, jako nieliniowe elementy, wykazują˛ intrygujące zjawiska w takich systemach. Przetestowano różne konfiguracje, w tym połączenia w trójkąt, w gwiazdę z trzema i czterema przewodami. Zebrane dane zostały przeanalizowane i przedstawione. Dokonano analizy częstotliwościowej FFT oraz wyznaczono współczynniki całkowitego zniekształcenia harmonicznego THD. Następnie uzyskane wyniki pomiarowe zostały zamodelowane z wykorzystaniem modelu memrystora MMS i porównane z danymi rzeczywistymi.

2

Evaluation of computational performance of PUF implementation for IoT device authentication

Makowski Łukasz

Przegląd Elektrotechniczny

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2025

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R. 101, nr 3

229--232

EN

One of the major challenges in the Internet of Things (IoT) is effectively authenticating large numbers of active node devices without relying on information stored on them and without requiring technical knowledge from users. Physical Unclonable Functions (PUFs) offer a viable alternative by exploiting the unique physical properties of electrical circuits to securely and reliably generate device-specific signatures. This paper examines the computational efficiency of processing data streams from a nonlinear oscillator circuit used to generate identifiers on a microcontroller.

PL

Jednym z głównych wyzwań w Internecie Rzeczy (IoT) jest skuteczne uwierzytelnianie dużej liczby aktywnych urządzeń bez polegania na przechowywanych na nich informacjach i bez wymogu posiadania wiedzy technicznej przez użytkowników. Fizyczne funkcje nieklonowalne (PUF) oferują realną alternatywę, wykorzystując unikalne właściwości fizyczne obwodów elektrycznych do bezpiecznego i niezawodnego generowania sygnatur specyficznych dla urządzeń. Niniejsza praca bada efektywność obliczeniową przetwarzania strumieni danych z obwodu oscylatora nieliniowego do generowania identyfikatorów na mikrokontrolerze.

3

A computationally tractable stabilizing predictive controller with fuzzy cost functions for discrete-time nonlinear systems

Teniou Samir

Przegląd Elektrotechniczny

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2025

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R. 101, nr 11

309--317

EN

A novel stabilizing controller for discrete-time nonlinear systems that uses a fuzzy receding horizon feedback control law is presented. The control input and the state variables are both subject to constraints in this controller. The membership functions of the fuzzy goals and the fuzzy constraints in the fuzzy cost function handles those imposed constraints. We prove asymptotic stability of the infinite horizon fuzzy optimal control law that uses the product as an aggregation operator with respect to time. This result is essential for showing that the finite horizon’s closed-loop asymptotic stability can be guaranteed using just the standard final region constraint and, in this case, the switching to the local stabilizing controller will not be necessary inside this final region. The main contribution of the paper is a practical and computationally tractable suboptimal fuzzy receding horizon control scheme that is asymptotically stabilizing. The effectiveness of the proposed scheme is shown by simulations on a continuous stirred tank reactor (CSTR) model.

PL

Przedstawiono nowatorski regulator stabilizujący dla dyskretnych układów nieliniowych, który wykorzystuje prawo sterowania ze sprzężeniem zwrotnym z rozmytym horyzontem ustępującym. Zarówno sygnał wejściowy sterowania, jak i zmienne stanu podlegają ograniczeniom w tym regulatorze. Funkcje przynależności celów rozmytych i ograniczenia rozmyte w funkcji kosztu rozmytego uwzględniają te narzucone ograniczenia. Dowodzimy asymptotycznej stabilności prawa sterowania optymalnego rozmytego o nieskończonym horyzoncie, które wykorzystuje iloczyn jako operator agregacji względem czasu. Wynik ten jest kluczowy dla wykazania, że asymptotyczna stabilność zamkniętej pętli skończonego horyzontu może być zagwarantowana przy użyciu jedynie standardowego ograniczenia obszaru końcowego, a w tym przypadku przełączanie na lokalny regulator stabilizujący nie będzie konieczne wewnątrz tego obszaru końcowego. Głównym wkładem artykułu jest praktyczny i łatwy w obliczeniach suboptymalny schemat sterowania z rozmytym horyzontem ustępującym, który jest asymptotycznie stabilizujący. Skuteczność proponowanego schematu została wykazana za pomocą symulacji przeprowadzonych na modelu reaktora zbiornikowego z ciągłym mieszaniem.

4

Controllability of Impulsive Second-order System using Functional Analytic Approach

Badiyani Sanket, Chudasama Neeta, Vaghela Vimalkumar, Patel Khushi, Shah Vishant

Mathematica Applicanda

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2025

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Vol 53, no. 2

167--183

EN

This article examines the exact controllability of second-order nonlinear abstract impulsive systems. The controllability of linear impulsive systems is addressed through the application of operator theory, while the analysis of nonlinear systems leverages nonlinear functional analysis and the fixed point theorem. An illustrative example is provided to reinforce the theoretical findings, demonstrating the practical validity of the results.

PL

W niniejszym artykule analizowana jest dokładna sterowalność nieliniowych abstrakcyjnych układów impulsowych drugiego rzędu. Sterowalność liniowych układów impulsowych jest analizowana poprzez zastosowanie teorii operatorów, natomiast analiza układów nieliniowych wykorzystuje nieliniową analizę funkcjonalną i twierdzenie o punkcie stałym. W celu wzmocnienia ustaleń teoretycznych przedstawiono przykład ilustrujący praktyczną ważność wyników.

5

Observer-based linear state-dependent control for blood glucose regulation in type 1 diabetic patients with unknown delays

Castro-Gómez J., Targui B., Hernández-González O., Valencia-Palomo G., Guerrero-Sánchez M. E.

Biocybernetics and Biomedical Engineering

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2025

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Vol. 45, iss. 2

189--198

EN

This paper presents a control strategy for blood glucose regulation in the presence of a time-varying delayed input, where the delay is unknown. The proposed control scheme is based on an observer-based linear state-dependent (LSD) (a subclass of the general linear parameter varying (LPV) framework) control with 𝐻∞ criterion. This proposed control regulates glucose levels in response to meal intake. A novel LSD system representation is used to relax the inherent conservativeness of the nonlinear system. First, the observer achieves an estimate of the current state vector despite the delayed input, where the time-varying unknown delay can be relatively long. Thus, the control law will perform well in the presence of a long unknown delay. The observer-based control scheme is validated by considering different meal disturbances and unknown delay scenarios.

6

Analytical modeling of the harmonic distortion caused by squeeze film damping in MEMS-based acoustic transducers

Melnikov Anton, Schenk Hermann A.G., Wall Franziska

Vibrations in Physical Systems

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2024

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Vol. 35, nr 1

art. no. 2024106

EN

Miniaturized microelectromechanical system (MEMS) microspeakers are currently trending in the development of acoustic transducers. When a transducer is scaled down to fit on a microelectronic chip, its physics differ from the macroscopic world, and some common modeling assumptions become invalid. One of the effects observed in MEMS microspeakers is nonlinear squeeze film damping. Understanding this effect is crucial, as non-linearities in the speaker can result in perceptible harmonic distortions, which are undesirable in audio applications. In this study, we analyze the influence of squeeze film damping on harmonic distortions using a lumped parameter model of a MEMS microspeaker. This leads to a nonlinear ordinary differential equation, and an approximate analytical solution for moderate non-linearities is obtained using homotopy. We present our solution strategy, including the resulting closed-form expression, and verify our findings against numerical solutions.

7

Filtr Kalmana jako alternatywa dla rozszerzonego obserwatora stanu w algorytmie regulacji ADRC

Michalski Jacek, Mrotek Mikołaj, Kozierski Piotr

Pomiary Automatyka Robotyka

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2024

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R. 28, nr 1

31--39

PL

W artykule przedstawiono zmodyfikowany algorytm odpornej regulacji z aktywną kompensacją zaburzeń ADRC z wykorzystaniem filtru Kalmana KF do estymacji rozszerzonego wektora stanu. Filtrem Kalmana zastąpiono używany w podstawowej formie rozszerzony obserwator stanu ESO. Modyfikacja ta pozwoliła na poprawę odporności układu w warunkach działania pomiarowych zakłóceń stochastycznych. Przedstawiono sposób syntezy układu regulacji i doboru nastaw filtru Kalmana zapewniający skuteczność sterowania, a także pokazano ich wpływ na działanie układu. Eksperymenty zostały przeprowadzone na układzie laboratoryjnym z balansującą na stole kulą BBT. Jakość regulacji została oceniona na podstawie przebiegów czasowych oraz całkowych wskaźników jakości, dla różnych konfiguracji nastaw oraz poziomów zaszumienia. W wyniku badań wykazana została przewaga zastosowania filtru Kalmana nad obserwatorem pod kątem wrażliwości na szumy pomiarowe. Zastosowanie filtru Kalmana jako estymatora dla rozszerzonego stanu wykazało pozytywny wpływ na jakość regulacji i zdolność do odrzucania zakłóceń wewnętrznych również w układzie deterministycznym.

EN

The article presents a modified Active Disturbance Rejection Control (ADRC) algorithm that uses the Kalman Filter (KF) for the estimation of extended state vector. The Kalman filter replaced the Extended State Observer (ESO) used in its basic form. The purpose of this modification was to improve the system robustness under conditions of stochastic measurement disturbances. The method of the control system synthesis and the Kalman filter gains selection, ensuring control efficiency, as well as their impact on the system operation, were presented. The experiments were carried out on a laboratory setup - the Ball Balancing Table (BBT). Control quality was assessed based on time plots of signals and integral performance indices for various algorithm gains configurations and different noise levels. As a result of the conducted research, the advantage of using the Kalman filter over the ESO in terms of sensitivity to measurement noises was demonstrated. Implementation of the Kalman filter as the ESO determined a positive impact on control quality and the ability to reject internal disturbance also in a deterministic system.

8

Dynamic sliding mode control based on a full-order observer: Underactuated electro-mechanical system regulation

Ordaz Patricio, Romero-Trejo Hugo, Cuvas Carlos, Sandre Omar

International Journal of Applied Mathematics and Computer Science

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2024

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Vol. 34, no. 1

29--43

EN

This paper concerns the synthesis of a nonlinear robust output controller based on a full-order observer for a class of uncertain disturbed systems. The proposed method guarantees that, in finite time, the system trajectories go inside a minimal neighborhood ultimately bounded. To this end, the attractive ellipsoid method is enhanced by applying the dynamic sliding mode control performance properties. Furthermore, in order to guarantee the stability of the trajectory around the trivial solution in the uniform-ultimately bounded sense, the feasibility of a specific matrix inequality problem is provided. With this feasible set of matrix inequalities, the separation principle of the controller/observer scheme considered also holds. To achieve a system performance improvement, a numerical algorithm based on the small size ultimate bound is presented. Finally, to illustrate the theoretical performance of the designed controller/observer, a numerical example dealing with the stabilization of a disturbed electromechanical system with uncertain and unmodeled dynamics is presented.

9

Robust flat filtering control of a two degrees of freedom helicopter subject to tail rotor disturbances

Sánchez-Meza Victor-Gabriel, Lozano-Hernández Yair, Gutiérrez-Frías Octavio, Lozada-Castillo Norma, Luviano-Juárez Alberto

International Journal of Applied Mathematics and Computer Science

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2023

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Vol. 33, no. 4

521--535

EN

This article deals with modelling and a flatness-based robust trajectory tracking scheme for a two degrees of freedom helicopter, which is subject to four types of tail rotor disturbances to validate the control scheme robustness. A mathematical model of the system, its differential flatness and a differential parametrization are obtained. The flat filtering control is designed for the system control with a partially known model, assuming the non-modelled dynamics and the external disturbances (specially the tail rotor ones) to be rejected by means of an extended state model (ultra-local model). Numerical and experimental assessments are carried out on a characterized prototype whose yaw angle (ψ), given by the z axis, is in free form, while the pitch angle (θ), which results from rotation about the y axis, is mechanically restricted. The proposed controller performance is tested through a set of experiments in trajectory tracking tasks with different disturbances in the tail rotor, showing robust behaviour for the different disturbances. Besides, a comparison study against a widely used controller of LQR type is carried out, in which the proposed controller achieves better results, as illustrated by a performance index.

10

Global stability of discrete-time feedback nonlinear systems with descriptor positive linear parts and interval state matrices

Kaczorek Tadeusz, Ruszewski Andrzej

International Journal of Applied Mathematics and Computer Science

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2022

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Vol. 32, no. 1

5--10

EN

The global stability of discrete-time nonlinear systems with descriptor positive linear parts, positive scalar feedbacks and interval state matrices is addressed. Sufficient conditions for the global stability of this class of nonlinear systems are established. The effectiveness of these conditions is illustrated using numerical examples.

11

Fault-tolerant tracking control for a non-linear twin-rotor system under ellipsoidal bounding

Kukurowski Norbert, Mrugalski Marcin, Pazera Marcin, Witczak Marcin

International Journal of Applied Mathematics and Computer Science

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2022

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Vol. 32, no. 2

171--183

EN

A novel fault-tolerant tracking control scheme based on an adaptive robust observer for non-linear systems is proposed. Additionally, it is presumed that the non-linear system may be faulty, i.e., affected by actuator and sensor faults along with the disturbances, simultaneously. Accordingly, the stability of the robust observer as well as the fault-tolerant tracking controller is achieved by using the ℋ∞ approach. Furthermore, unknown actuator and sensor faults and states are bounded by the uncertainty intervals for estimation quality assessment as well as reliable fault diagnosis. This means that narrow intervals accompany better estimation quality. Thus, to cope with the above difficulty, it is assumed that the disturbances are over-bounded by an ellipsoid. Consequently, the performance and correctness of the proposed fault-tolerant tracking control scheme are verified by using a non-linear twin-rotor aerodynamical laboratory system.

12

A data driven fault isolation method based on reference faulty situations with application to a nonlinear chemical process

Ragot José, Mourot Gilles, Kallas Maya

International Journal of Applied Mathematics and Computer Science

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2022

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Vol. 32, no. 4

635--655

EN

The diagnosis of systems is one of the major steps in their control and its purpose is to determine the possible presence of dysfunctions, which affect the sensors and actuators associated with a system but also the internal components of the system itself. On the one hand, the diagnosis must therefore focus on the detection of a dysfunction and, on the other hand, on the physical localization of the dysfunction by specifying the component in a faulty situation, and then on its temporal localization. In this contribution, the emphasis is on the use of software redundancy applied to the detection of anomalies within the measurements collected in the system. The systems considered here are characterized by non-linear behaviours whose model is not known a priori. The proposed strategy therefore focuses on processing the data acquired on the system for which it is assumed that a healthy operating regime is known. Diagnostic procedures usually use this data corresponding to good operating regimes by comparing them with new situations that may contain faults. Our approach is fundamentally different in that the good functioning data allow us, by means of a non-linear prediction technique, to generate a lot of data that reflect all the faults under different excitation situations of the system. The database thus created characterizes the dysfunctions and then serves as a reference to be compared with real situations. This comparison, which then makes it possible to recognize the faulty situation, is based on a technique for evaluating the main angle between subspaces of system dysfunction situations. An important point of the discussion concerns the robustness and sensitivity of fault indicators. In particular, it is shown how, by non-linear combinations, it is possible to increase the size of these indicators in such a way as to facilitate the location of faults.

13

Highly nonlinear systems estimation using extended and unscented kalman filters

Laamari Yahia, Allaoui Samia, Chafaa Kheireddine, Bendaikha Abdelmalik

Przegląd Elektrotechniczny

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2021

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R. 97, nr 5

111--115

EN

The main idea of this study is to evaluate the estimation performance of extended and unscented Kalman filters (EKF and UKF). So, these latter are introduced to estimate the dynamic states of a similar model operating with identical covariance matrices in the same situation. The mean square error (MSE) criterion is used to quantify the estimation error between the actual and the estimated values. The simulation results obtained with Matlab/ Simulink software confirm the superiority and efficiency of UKF over EKF, especially when the system is highly non-linear under process and measurement noises, such is the case of the inverted double pendulum mounted on a cart (DIPC).

PL

Główną ideą tego badania jest ocena wydajności estymacji rozszerzonych filtrów Kalmana (EKF i UKF). Te ostatnie zostały wprowadzone w celu oszacowania stanów dynamicznych podobnego modelu działającego z identycznymi macierzami kowariancji. Kryterium błędu średniokwadratowego (MSE) służy do ilościowego określenia błędu oszacowania między wartościami rzeczywistymi i szacunkowymi. Wyniki symulacji uzyskane za pomocą oprogramowania Matlab i Simulink potwierdzają wyższość i wydajność UKF nad EKF, zwłaszcza gdy system jest wysoce nieliniowy

14

Global stability of positive discrete-time time-varying nonlinear feedback systems

Kaczorek Tadeusz, Sajewski Łukasz

Journal of Automation, Electronics and Electrical Engineering

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2021

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Vol. 3, No. 1

17--20

EN

The global stability of positive discrete-time time-varying nonlinear systems with time-varying scalar feedbacks is investigated. Sufficient conditions for the asymptotic stability of discrete-time positive time-varying linear systems are given. The new conditions are applied to discrete-time positive time-varying nonlinear systems with time-varying feedbacks. Sufficient conditions are established for the global stability of the discrete-time positive time-varying nonlinear systems with feedbacks.

15

Bandwidth selection for kernel generalized regression neural networks in identification of hammerstein systems

Lv Jiaqing, Pawlak Mirosław

Journal of Artificial Intelligence and Soft Computing Research

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2021

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Vol. 11, No. 3

181--194

EN

This paper addresses the issue of data-driven smoothing parameter (bandwidth) selection in the context of nonparametric system identification of dynamic systems. In particular, we examine the identification problem of the block-oriented Hammerstein cascade system. A class of kernel-type Generalized Regression Neural Networks (GRNN) is employed as the identification algorithm. The statistical accuracy of the kernel GRNN estimate is critically influenced by the choice of the bandwidth. Given the need of data-driven bandwidth specification we propose several automatic selection methods that are compared by means of simulation studies. Our experiments reveal that the method referred to as the partitioned cross-validation algorithm can be recommended as the practical procedure for the bandwidth choice for the kernel GRNN estimate in terms of its statistical accuracy and implementation aspects.

16

A computationally inexpensive algorithm for determining outer and inner enclosures of nonlinear mappings of ellipsoidal domains

Rauh Andreas, Jaulin Luc

International Journal of Applied Mathematics and Computer Science

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2021

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Vol. 31, no. 3

399--415

EN

A wide variety of approaches for set-valued simulation, parameter identification, state estimation as well as reachability, observability and stability analysis for nonlinear discrete-time systems involve the propagation of ellipsoids via nonlinear functions. It is well known that the corresponding image sets usually possess a complex shape and may even be nonconvex despite the convexity of the input data. For that reason, domain splitting procedures are often employed which help to reduce the phenomenon of overestimation that can be traced back to the well-known dependency and wrapping effects of interval analysis. In this paper, we propose a simple, yet efficient scheme for simultaneously determining outer and inner ellipsoidal range enclosures of the solution for the evaluation of multi-dimensional functions if the input domains are themselves described by ellipsoids. The Hausdorff distance between the computed enclosure and the exact solution set reduces at least linearly when decreasing the size of the input domains. In addition to algebraic function evaluations, the proposed technique is-for the first time, to our knowledge-employed for quantifying worst-case errors when extended Kalman filter-like, linearization-based techniques are used for forecasting confidence ellipsoids in a stochastic setting.

17

Memristive devices In three-phase systems

Zegarmistrz Piotr, Garda Bartłomiej

Przegląd Elektrotechniczny

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2020

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R. 96, nr 1

11--14

EN

The aim of the research presented in a paper was to provide trustworthy simulation results for symmetrical three-phase systems with memristive load. The memristors in the system are combined with linear resistors in order to limit the current in the element. Linear drift model of the memristorwasconsideredinMatlabsimulations. ItisbasedonStrukovmodelwithBiolekwindow. Highnonlinearityofmemristorresultsindeformation of most of the signals in the system. Since the voltage of the neutral point is highly non-sinusoidal it affects on other signals like phase voltage, phase currents, delta voltages. A Fast Fourier Transform (FFT) is applied to chosen signals in order to provide a frequency spectrum. On this basis a Total Harmonic Distortion (THD) parameter was calculated.

PL

W pracy zaprezentowano wyniki badań symulacyjnych nad układem trójfazowym symetrycznym z obciążeniem elementami memrystorowymi. Memrystory w obwodzie odbiornika są połączone szeregowo z rezystorami liniowymi w celu ograniczenia prądu. W obliczeniach symulacyjnych przyjęto model memrystora "linear drift", bazujący na modelu Strukova z oknem Biolka. Wysoka nieliniowość elementów memrystorowych skutkuje odkształceniem większości sygnałów w obwodzie. Skoro napięcie punktu neutralnego odbiornika wykazuje wysoką nieliniowość, to skutkuje to odkształceniem pozostałych sygnałów, t.j. napięć fazowych, prądów fazowych czy napięć przewodowych. Do wybranych sygnałów zastosowano Szybką Transformatę Fouriera (FTT) w celu zaprezentowania widma częstotliwościowego. Na tej podstawie obliczono Współczynnik Zawartości Harmonicznych.

18

A unique weak solution for a kind of coupled system of fractional Schrodinger equations

Abdolrazaghi Fatemeh, Razani Abdolrahman

Opuscula Mathematica

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2020

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Vol. 40, no. 3

313--322

EN

In this paper, we prove the existence of a unique weak solution for a class of fractional systems of Schrodinger equations by using the Minty-Browder theorem in the Cartesian space. To this aim, we need to impose some growth conditions to control the source functions with respect to dependent variables.

19

Global stability of nonlinear feedback systems with fractional positive linear parts

Kaczorek Tadeusz

International Journal of Applied Mathematics and Computer Science

|

2020

|

Vol. 30, no. 3

493--499

EN

The global (absolute) stability of nonlinear systems with fractional positive and not necessarily asymptotically stable linear parts and feedbacks is addressed. The characteristics u = f(e) of the nonlinear parts satisfy the condition k1e ≤ f(e) ≤ k2e for some positive k1 and k2. It is shown that the fractional nonlinear systems are globally asymptotically stable if the Nyquist plots of the fractional positive linear parts are located on the right-hand side of the circles (−1/k1,−1/k2).

20

Global stability of positive standard and fractional nonlinear feedback systems

Kaczorek T.

Bulletin of the Polish Academy of Sciences. Technical Sciences

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2020

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Vol. 68, nr 2

285--288

EN

The global stability of positive continuous-time standard and fractional order nonlinear feedback systems is investigated. New sufficient conditions for the global stability of these classes of of positive nonlinear systems are established. The effectiveness of these new stability conditions is demonstrated on simple examples of positive nonlinear systems.