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Tytuł:
A new approach to robust finite-time H∞ control of continuous-time Markov jump systems
Autorzy:
Yan, S.
Shen, M.
Fei, S.
Zhang, G.
Powiązania:
https://bibliotekanauki.pl/articles/206785.pdf
Data publikacji:
2015
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
Markov jump systems
partly known transition probabilities
rob ust finite-time H∞control
Opis:
This paper studies the robust finite-time H∞ state feedback control problem of continuous-time Markov jump systems (MJSs) subject to norm bounded uncertainties. Transition probabilities are allowed to be known, uncertain with known bounds or unknown. Based on the continuous transition probability property and the developed slack variable technique, Lyapunov variables are separatek from unknown transition probabilities and system matrices. With these separations, a relaxed method for robust finite-time H∞ controller design is proposed in terms of linear matrix inequalities (LMIs). Numerical examples are given to illustrate the effectiveness of and the benefit from the proposed method.
Źródło:
Control and Cybernetics; 2015, 44, 2; 211-231
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A novel robust H1 fuzzy state-feedback control design on nonlinear Markovian jump systems with time-varyin delay
Autorzy:
Assawinchaichote, W.
Powiązania:
https://bibliotekanauki.pl/articles/205767.pdf
Data publikacji:
2014
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
H∞ fuzzy control
Takagi-Sugeno (TS) fuzzy model
linear matrix inequalities (LMIs)
Markovian jump parameters
time-varying delay
Opis:
This paper considers the problem of designing a robust H∞ fuzzy state-feedback controller for a class of nonlinear Markovian jump systems with time-varying delay. A novel design methodology has been proposed for designing a controller that guarantees the L2-gain of the mapping from the exogenous input noise to the regulated output to be less than some prescribed value. Solutions to the problem are provided in terms of linear matrix inequalities. To illustrate the effectiveness of the design developed in this paper, a numerical example is also provided.
Źródło:
Control and Cybernetics; 2014, 43, 2; 227-248
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A spectral method of the analysis of linear control systems
Autorzy:
Kurdyukov, Alexander P.
Boichenko, Victor A.
Powiązania:
https://bibliotekanauki.pl/articles/329786.pdf
Data publikacji:
2019
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
anisotropy based control theory
anisotropic norm
ℋ2-norm
H∞ norm
teoria sterowania
norma anizotropowa
norma H-nieskończoność
Opis:
A spectral method of the analysis of linear control systems is considered. Within the framework of this approach the σ-entropy of input signals and the σ-entropy norm of systems are introduced. The invariance of the introduced norm makes it possible to get invariant results of σ-entropy analysis.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2019, 29, 4; 667-679
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An investigation into vibration control of gear bearing systems
Autorzy:
Saghafi, Amin
Farshidianfar, Anooshirvan
Powiązania:
https://bibliotekanauki.pl/articles/1845021.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
gear bearing system
vibration control
H-infinity control
active control
system przekładni zębatych
kontrola wibracji
kontrola aktywna
Opis:
Considering the importance of gear systems as one of the important vibration and noise sources in power transmission systems, an active control for suppressing gear vibration is presented in this paper. A gear bearing model is developed and used to design an active control gear-bearing system. Two possible configurations of control system are designed based on active bearing and active gear-shaft torsional coupling to control and reduce the disturbance affecting system components. The controller for computing the actuation force is designed by using the H-infinity control approach. Simulation results indicate that the desired controller can efficiently be used for vibration control of gear bearing systems.
Źródło:
Archive of Mechanical Engineering; 2021, LXVIII, 4; 473-491
0004-0738
Pojawia się w:
Archive of Mechanical Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Automatic Control of Mechatronic Systems
Autorzy:
Schlacher, K.
Kugi, A.
Powiązania:
https://bibliotekanauki.pl/articles/908321.pdf
Data publikacji:
2001
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
mechatronika
geometria różniczkowa
sterowanie
mechatronic systems
differential geometry
nonlinear H_{infty}-control
passivity
input-output linearization
Opis:
This contribution deals with different concepts of nonlinear control for mechatronic systems. Since most physical systems are nonlinear in nature, it is quite obvious that an improvement in the performance of the closed loop can often be achieved only by means of control techniques that take the essential nonlinearities into consideration. Nevertheless, it can be observed that industry often hesitates to implement these nonlinear controllers, despite all advantages existing from the theoretical point of view. On the basis of three different applications, a PWM-controlled dc-to-dc converter, namely the Cuk-converter, the problem of hydraulic gap control in steel rolling, and the design of smart structures with piezolelectric sensor and actuator layers, we will demonstrate how one can overcome these problems by exploiting the physical structure of the mathematical models of the considered plants.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2001, 11, 1; 131-164
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Charakterystyka metod zapobiegania powstawaniu bromianów(V) w wodzie przeznaczonej do spożycia
Characteristics of bromate formation prevention methods in water intended for human consumption
Autorzy:
Olsińska, U.
Powiązania:
https://bibliotekanauki.pl/articles/236674.pdf
Data publikacji:
2017
Wydawca:
Polskie Zrzeszenie Inżynierów i Techników Sanitarnych
Tematy:
tap water
bromate formation control
bromide removal
ozonation optimization
water ammonification
H2O2 dosing
woda do spożycia
bromiany
zapobieganie
usuwanie bromków
optymalizacja ozonowania
amonizacja wody
dawkowanie H2O2
Opis:
Bromate content following ozonation of bromide-containing water may range from 0.4 to 60 mgBrO3–/m3. Based on toxicological studies, bromates are classified as potential human carcinogens and are subject to legal regulations in many countries. In Europe, since the 25th of December 2008 their maximum permissible content in water intended for human consumption must not exceed 10 mgBrO3–/m3. As bromates are stable compounds, difficult to remove using conventional water treatment technologies, novel techniques to control their formation in water need to be developed. Technologies meant to control the bromate content in water can be divided into two groups: (1) methods allowing limitation of bromate formation and (2) methods for bromate removal. Methods that may be applied to control the bromate formation in water intended for human consumption are briefly reviewed herein. Evaluation of progress in their development was performed as well as feasibility of their application in water treatment systems was assessed. The review outlines both the well-known methods (e.g. lowering of pH, water ammonification, bromide removal in conventional water treatment processes, operational parameter optimization, multi-stage ozonation, addition of OH radical scavengers, hydrogen peroxide dosing) and the novel ones (e.g. membrane processes for bromide removal, catalytic ozonation, strong oxidant dosing). Selection of an appropriate solution to the problem of increased bromate presence in water should always be preceded by pilot studies. The main reasons include a complex mechanism of bromate formation and simultaneous effect of various water quality indicators on the effectiveness of different bromate formation prevention methods.
Zawartość bromianów(V) po procesie ozonowania wody zawierającej bromki może sięgać od 0,4 mgBrO3–/m3 do 60 mgBrO3–/m3. Na podstawie wyników badań toksykologicznych bromiany(V) zostały zakwalifikowane do grupy potencjalnych kancerogenów i są przedmiotem regulacji prawnych w wielu krajach. W Europie, od 25 grudnia 2008 r., ich maksymalna dopuszczalna zawartość w wodzie przeznaczonej do spożycia nie może przekraczać 10 mgBrO3–/m3. Ponieważ bromiany(V) są związkami trwałymi i trudno usuwalnymi za pomocą konwencjonalnych procesów oczyszczania wody, dlatego niezbędne jest opracowanie nowych technik kontroli ich powstawania w wodzie. Technologie przydatne do kontroli zawartości bromianów(V) w wodzie można podzielić na dwie grupy: (1) metody umożliwiające ograniczenie powstawania bromianów(V), (2) metody usuwania bromianów(V). W pracy omówiono metody, które mogą być wykorzystane do kontroli powstawania bromianów(V) w wodzie przeznaczonej do spożycia przez ludzi. Dokonano także oceny postępu w ich opracowaniu, jak również możliwości ich stosowania w systemach oczyszczania wody. W rozważaniach uwzględniono zarówno metody dobrze znane (np. obniżenie wartości pH wody, amonizacja wody, usuwanie bromków w konwencjonalnych procesach oczyszczania wody, optymalizacja parametrów procesowych, ozonowanie wieloetapowe, dawkowanie akceptorów rodników OH, dawkowanie nadtlenku wodoru), jak i nowsze (zastosowanie technik membranowych do usuwania bromków, ozononowanie katalityczne oraz dawkowanie silnych utleniaczy). Wybór właściwego rozwiązania problemu zwiększonej obecności bromianów(V) w wodzie, ze względu na złożony mechanizm ich tworzenia i jednoczesny wpływ wielu wskaźników jakości wody na skuteczność poszczególnych metod zapobiegania ich powstawaniu, powinien być zawsze poprzedzony badaniami pilotowymi.
Źródło:
Ochrona Środowiska; 2017, 39, 2; 17-26
1230-6169
Pojawia się w:
Ochrona Środowiska
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Control Mechanisms in the Process of Preventing. Corruption in Public Administration Offices on the Example of Entities in the Podkarpackie Province
Autorzy:
Walenia, Alina
Powiązania:
https://bibliotekanauki.pl/articles/652685.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Łódzki. Wydawnictwo Uniwersytetu Łódzkiego
Tematy:
control
corruption
public administration
H70
M14
Opis:
A crucial element of the mechanism to prevent corruption in public administration is the explicit procedure of reacting to corruption events, regardless of whether it is based on ISO procedures or if it results from another system of legal solutions. The statutory anti-corruption solutions introduced in public institutions in the form of management control involve the staff abiding by ethical values, and they serve to improve the transparency, legal conduct, and ethics in the operations of a public administration office. The results of empirical research confirm that the implemented management control procedures form integral parts of the anti-corruption system in public entities.
Źródło:
Annales. Etyka w Życiu Gospodarczym; 2016, 19, 4
1899-2226
2353-4869
Pojawia się w:
Annales. Etyka w Życiu Gospodarczym
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Decentralized design of interconnected H infinity feedback control systems with quantized signals
Autorzy:
Zhai, G.
Chen, N.
Gui, W.
Powiązania:
https://bibliotekanauki.pl/articles/331266.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
interconnected systems
decentralized H infinity control
dynamic output feedback
quantizer
quantization
matrix inequality
LMI
sprzężenie zwrotne dynamiczne
kwantyzer
kwantowanie
nierówność macierzowa
metoda LMI
Opis:
In this paper, we consider the design of interconnected H infinity feedback control systems with quantized signals. We assume that a decentralized dynamic output feedback has been designed for an interconnected continuous-time LTI system so that the closed-loop system is stable and a desired H infinity disturbance attenuation level is achieved, and that the subsystem measurement outputs are quantized before they are passed to the local controllers. We propose a local-output-dependent strategy for updating the parameters of the quantizers, so that the overall closed-loop system is asymptotically stable and achieves the same H infinity disturbance attenuation level. Both the pre-designed controllers and the parameters of the quantizers are constructed in a decentralized manner, depending on local measurement outputs.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2013, 23, 2; 317-325
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Delay-dependent generalized H2 control for discrete T-S fuzzy large-scale stochastic systems with mixed delays
Autorzy:
Li, J.
Xia, Z.
Powiązania:
https://bibliotekanauki.pl/articles/930162.pdf
Data publikacji:
2011
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
system stochastyczny
opóźnienie zależne
liniowa nierówność macierzowa
fuzzy large scale stochastic system
delay-dependent
generalized H2 control
infinite distributed delays
linear matrix inequality
Opis:
This paper is concerned with the problem of stochastic stability and generalized H2 control for discrete-time fuzzy largescale stochastic systems with time-varying and infinite-distributed delays. Large-scale interconnected systems consist of a number of discrete-time interconnected Takagi-Sugeno (T-S) subsystems. First, a novel Delay-Dependent Piecewise Lyapunov-Krasovskii Functional (DDPLKF0 is proposed, in which both the upper and the lower bound of delays are considered. Then, two improved delay-dependent stability conditions are established based on this DDPLKF in terms of Linear Matrix Inequalities (LMIs). The merit of the proposed conditions lies in its reduced conservatism, which is achieved by circumventing the utilization of some bounding inequalities for cross products of two vectors and by considering the interactions among the fuzzy subsystems in each subregion. A decentralized generalized H2 state feedback fuzzy controller is designed for each subsystem. It is shown that the mean-square stability for discrete T-S fuzzy large-scale stochastic systems can be established if a DDPLKF can be constructed and a decentralized controller can be obtained by solving a set of LMIs. Finally, an illustrative example is provided to demonstrate the effectiveness of the proposed method.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2011, 21, 4; 585-603
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Experimental verification of H∞ control with examples of the movement of a wheeled robot
Autorzy:
Hendzel, Zenon
Penar, Paweł
Powiązania:
https://bibliotekanauki.pl/articles/2086871.pdf
Data publikacji:
2021
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
differential game
H∞ control
wheeled mobile robot
gry różniczkowe
sterowanie H∞
kołowy robot mobilny
Opis:
The paper presents the results of experimental verification on using a zero-sum differential game and H∞ control in the problems of tracking and stabilizing motion of a wheeled mobile robot (WMR). It is a new approach to the synthesis of input-output systems based on the theory of dissipative systems in the sense of the possibility of their practical application. This paper expands upon the problem of optimal control of a nonlinear, nonholonomic wheeled mobile robot by including the reduced impact of changing operating condtions and possible disturbances of the robot’s complex motion. The proposed approach is based on the H∞ control theory and the control is generated by the neural approximation solution to the Hamilton-Jacobi-Isaacs equation. Our verification experiments confirm that the H∞ condition is met for reduced impact of disturbances in the task of tracking and stabilizing the robot motion in the form of changing operating conditions and other disturbances, which made it possible to achieve high accuracy of motion.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2021, 69, 6; e139390, 1--12
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Finite-dimensional H∞ control of a parallel-flow heat exchange process
Autorzy:
Sano, H.
Powiązania:
https://bibliotekanauki.pl/articles/200376.pdf
Data publikacji:
2017
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
distributed parameter system H∞ control
residual mode filter
semigroup
parametr kontroli systemu H∞
półgrupa
RMF
Opis:
This paper is concerned with the H∞ control problem of a coupled transport-diffusion system with Neumann boundary condition, related to parallel-flow heat exchange process. It is shown that, by using the previous approach for a single diffusion system, the H∞ control problem can be solved by constructing a residual mode filter (RMF)-based controller which is of finite-dimension. A numerical simulation result is given to demonstrate the validity of the proposed method.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2017, 65, 1; 11-19
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Grypa psów - nowa, niebezpieczna choroba zakaźna?
Canine influenza - an emerging, threatening disease?
Autorzy:
Gliński, Zdzisław
Żmuda, Andrzej
Powiązania:
https://bibliotekanauki.pl/articles/22176863.pdf
Data publikacji:
2020
Wydawca:
Krajowa Izba Lekarsko-Weterynaryjna
Tematy:
psy
choroby wirusowe
wirus H3N2 CIV
epidemiologia
objawy kliniczne
zmiany anatomopatologiczne
zmiany histopatologiczne
diagnostyka
leczenie
profilaktyka
choroby zakaźne
grypa psów
źródła zakażenia
influenza
dog
H3N2 CIV
H3N8 CIV
clinical signs
lesions
control
Opis:
Here, an emerging, threatening disease, influenza in dogs, is presented. Like other mammalian influenza viruses, canine influenza virus (CIV), causes an acute respiratory infection. There is no season for this disease and infections can occur any time of the year. Dogs have acquired two influenza viruses since 1999. Canine influenza H3N8 virus is thought to develop from an equine H3N8 strain, whereas canine H3N2 influenza virus most likely arose through the direct transfer of an avian influenza virus from birds. The H3N8 CIV has only been reported in dogs, whereas the H3N2 CIV has caused clinical cases in dogs and cats in Asia, and antibodies to this virus have been found in both species. Almost all dogs exposed to canine influenza virus become infected, with approximately 80% developing clinical signs of disease. Some dogs have asymptomatic infections, while some have severe illness, however death cases due to CIV infection are rare. Fatal H3N8 cases in racing greyhounds were often characterized by hemorrhages in the lungs, mediastinum and pleural cavity. Severe hemorrhagic, cranio-ventral broncho-interstitial pneumonia was reported in most fatal cases of canine H3N2 influenza in naturally infected dogs from Asia. Experimentally infected dogs also had signs of pneumonia with multifocal to coalescing reddish consolidation, edema and hemorrhages in the lungs. No lesions were found outside the respiratory tract. The majority of infected dogs have the mild form of canine influenza. The approximately 20% of infected animals that do not exhibit clinical signs of disease can still shed the virus. The diagnosis is performed by serological methods, with hemagglutination inhibition (HI) as the test of choice, and by molecular methods as RT-PCR. Treatment is supportive, and often includes antibiotics to control secondary bacterial infections. Vaccines for canine influenza are available in some areas. Infection control measures include isolation of infected animals, cleaning and disinfection of cages, bowls and other fomites, and hygiene measures.
Źródło:
Życie Weterynaryjne; 2020, 95, 11; 697-700
0137-6810
Pojawia się w:
Życie Weterynaryjne
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Identification of matrix parameters in elliptic PDEs
Autorzy:
Deckelnick, K.
Hinze, M.
Powiązania:
https://bibliotekanauki.pl/articles/206153.pdf
Data publikacji:
2011
Wydawca:
Polska Akademia Nauk. Instytut Badań Systemowych PAN
Tematy:
parameter identification
elliptic optimal control problem
control constraints
H-convergence
variational discretization
Opis:
In the present work we treat the inverse problem of identifying the matrix-valued diffusion coefficient of an elliptic PDE from multiple interior measurements with the help of techniques from PDE constrained optimization. We prove existence of solutions using the concept of H-convergence and employ variational discretization for the discrete approximation of solutions. Using a discrete version of H-convergence we are able to establish the strong convergence of the discrete solutions. Finally we present some numerical results.
Źródło:
Control and Cybernetics; 2011, 40, 4; 957-969
0324-8569
Pojawia się w:
Control and Cybernetics
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Loop-shaping h∞ control of an aeropendulum model
Autorzy:
Breganon, Ricardo
Alves, Uiliam Nelson L. T.
De Almeida, João Paulo L.S.
Ribeiro, Fernando S. F.
Mendonça, Marcio
Palácios, Rodrigo H. C.
Montezuma, Marcio A. F.
Powiązania:
https://bibliotekanauki.pl/articles/2106458.pdf
Data publikacji:
2021
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
modelowanie dynamiczne
wahadło aerodynamiczne
sterowanie
dynamic system modeling
aeropendulum
H∞ control
Opis:
This work presents a mathematical model of an aeropendulum system with two sets of motors with propellers and the design and simulation of a loop-shaping h∞control for this system. In this plant, the objective is to control the angular position of the pendulum rod through the torque generated by the thrust of the motorized propellers at the end of the rod’s axis. The control design is obtained by first using feedback linearization and then designing the h∞ controller using the resulting linear system. For the control strategy validation, simulations were conducted in the Matlab/Simulink® environment, and the weighting functions for the h∞ controller were adjusted to obtain the desired performance and stability of the closed-loop system. The simulation results show the efficiency of the applied methodology.
Źródło:
International Journal of Applied Mechanics and Engineering; 2021, 26, 4; 1--16
1734-4492
2353-9003
Pojawia się w:
International Journal of Applied Mechanics and Engineering
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Model predictive control of multilevel cascaded converter with boosting capability – a simulation study
Autorzy:
Wiatr, P.
Kazmierkowski, M. P.
Powiązania:
https://bibliotekanauki.pl/articles/201916.pdf
Data publikacji:
2016
Wydawca:
Polska Akademia Nauk. Czytelnia Czasopism PAN
Tematy:
cascaded H-bridge
CHB
model predictive control
MPC
multilevel converters
sterowanie predykcyjne
konwenter wielopoziomowy
Opis:
This paper presents a multilevel cascaded H-bridge 5-level converter with boosting capability. The standard solution for boosting voltage in power electronic devices is based on a DC-DC converter with a bulky inductor. However, inductor is a problematic component of a power electronic converter because usually it has to be individually designed and produced for every device and also because its size and weight do not allow for compact construction. This paper presents model predictive control (MPC) method that gives boosting capability for the presented converter. A novel contribution of this paper is the development of a predictive model of the converter and cost function enabling output current control and capacitor voltage balancing.
Źródło:
Bulletin of the Polish Academy of Sciences. Technical Sciences; 2016, 64, 3; 581-590
0239-7528
Pojawia się w:
Bulletin of the Polish Academy of Sciences. Technical Sciences
Dostawca treści:
Biblioteka Nauki
Artykuł
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