Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

Wyszukujesz frazę "system analysis" wg kryterium: Temat


Tytuł:
Local analysis of hybrid systems on polyhedral sets with state-dependent switching
Autorzy:
Leth, J.
Wisniewski, R.
Powiązania:
https://bibliotekanauki.pl/articles/330556.pdf
Data publikacji:
2014
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
inkluzja różniczkowa
badanie stabilności
układ hybrydowy
stability analysis
switched system
hybrid system
differential inclusion
Opis:
This paper deals with stability analysis of hybrid systems. Various stability concepts related to hybrid systems are introduced. The paper advocates a local analysis. It involves the equivalence relation generated by reset maps of a hybrid system. To establish a tangible method for stability analysis, we introduce the notion of a chart, which locally reduces the complexity of the hybrid system. In a chart, a hybrid system is particularly simple and can be analyzed with the use of methods borrowed from the theory of differential inclusions. Thus, the main contribution of this paper is to show how stability of a hybrid system can be reduced to a specialization of the well established stability theory of differential inclusions. A number of examples illustrate the concepts introduced in the paper.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2014, 24, 2; 341-355
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Stability analysis of interconnected discrete-time fractional-order LTI state-space systems
Autorzy:
Grzymkowski, Łukasz
Trofimowicz, Damian
Stefański, Tomasz P.
Powiązania:
https://bibliotekanauki.pl/articles/1838161.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
stability analysis
discrete time system
fractional order system
analiza stabilności
układ czasu dyskretnego
układ rzędu ułamkowego
Opis:
In this paper, a stability analysis of interconnected discrete-time fractional-order (FO) linear time-invariant (LTI) state-space systems is presented. A new system is formed by interconnecting given FO systems using cascade, feedback, parallel interconnections. The stability requirement for such a system is that all zeros of a non-polynomial characteristic equation must be within the unit circle on the complex z-plane. The obtained theoretical results lead to a numerical test for stability evaluation of interconnected FO systems. It is based on modern root-finding techniques on the complex plane employing triangulation of the unit circle and Cauchy’s argument principle. The developed numerical test is simple, intuitive and can be applied to a variety of systems. Furthermore, because it evaluates the function related to the characteristic equation on the complex plane, it does not require computation of state-matrix eigenvalues. The obtained numerical results confirm the efficiency of the developed test for the stability analysis of interconnected discrete-time FO LTI state-space systems.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2020, 30, 4; 649-658
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Mathematical methods of signal analysis applied in medical diagnostic
Autorzy:
Ciecierski, Konrad A.
Powiązania:
https://bibliotekanauki.pl/articles/331189.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
decision support system
signal filtering
data fusion
temporal analysis
system wspomagania decyzji
filtrowanie sygnału
fuzja danych
Opis:
Digital signal processing, such as filtering, information extraction, and fusion of various results, is currently an integral part of advanced medical therapies. It is especially important in neurosurgery during deep-brain stimulation procedures. In such procedures, the surgical target is accessed using special electrodes while not being directly visible. This requires very precise identification of brain structures in 3D space throughout the surgery. In the case of deep-brain stimulation surgery for Parkinson’s disease (PD), the target area—the subthalamic nucleus (STN)—is located deep within the brain. It is also very small (just a few millimetres across), which makes this procedure even more difficult. For this reason, various signals are acquired, filtered, and finally fused, to provide the neurosurgeon with the exact location of the target. These signals come from preoperative medical imaging (such as MRI and CT), and from recordings of brain activity carried out during surgery using special brain-implanted electrodes. Using the method described in this paper, it is possible to construct a decision-support system that, during surgery, analyses signals recorded within the patient’s brain and classifies them as recorded within the STN or not. The constructed classifier discriminates signals with a sensitivity of 0.97 and a specificity of 0.96. The described algorithm is currently used for deep-brain stimulation surgeries among PD patients.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2020, 30, 3; 449-462
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On-line wavelet estimation of Hammerstein system nonlinearity
Autorzy:
Śliwiński, P.
Powiązania:
https://bibliotekanauki.pl/articles/929599.pdf
Data publikacji:
2010
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
system Hammersteina
identyfikacja nieparametryczna
estymacja falkowa
analiza zbieżności
Hammerstein system
on-line nonparametric identification
wavelet estimates
convergence analysis
Opis:
A new algorithm for nonparametric wavelet estimation of Hammerstein system nonlinearity is proposed. The algorithm works in the on-line regime (viz., past measurements are not available) and offers a convenient uniform routine for nonlinearity estimation at an arbitrary point and at any moment of the identification process. The pointwise convergence of the estimate to locally bounded nonlinearities and the rate of this convergence are both established.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2010, 20, 3; 513-523
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Maintaining the feasibility of hard real-time systems with a reduced number of priority levels
Autorzy:
Qureshi, M. B.
Alrashed, S.
Min-Allah, N.
Kołodziej, J.
Arabas, P.
Powiązania:
https://bibliotekanauki.pl/articles/330305.pdf
Data publikacji:
2015
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
real time system
feasibility analysis
fixed priority scheduling
rate monotonic algorithm
online scheduling
system czasu rzeczywistego
analiza wykonalności
algorytm szeregowania
Opis:
When there is a mismatch between the cardinality of a periodic task set and the priority levels supported by the underlying hardware systems, multiple tasks are grouped into one class so as to maintain a specific level of confidence in their accuracy. However, such a transformation is achieved at the expense of the loss of schedulability of the original task set. We further investigate the aforementioned problem and report the following contributions: (i) a novel technique for mapping unlimited priority tasks into a reduced number of classes that do not violate the schedulability of the original task set and (ii) an efficient feasibility test that eliminates insufficient points during the feasibility analysis. The theoretical correctness of both contributions is checked through formal verifications. Moreover, the experimental results reveal the superiority of our work over the existing feasibility tests by reducing the number of scheduling points that are needed otherwise.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2015, 25, 4; 709-722
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A new sufficient schedulability analysis for hybrid scheduling
Autorzy:
Zhang, F.
Zhai, Y.
Liao, J.
Powiązania:
https://bibliotekanauki.pl/articles/330353.pdf
Data publikacji:
2016
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
scheduling algorithm
real time system
schedulability analysis
preemptive scheduling
earliest deadline first
fixed priority
algorytm szeregowania
system czasu rzeczywistego
analiza szeregowalności
Opis:
Earliest deadline first (EDF) and fixed priority (FP) are the most commonly used and studied scheduling algorithms for real-time systems. This paper focuses on combining the EDF and FP strategies in one system. We provide a new sufficient schedulability analysis for real-time hybrid task systems which are scheduled by EDF and FP. The proposed analysis has a polynomial time complexity and no restrictions on task parameters, where the relative deadline of each task could be less than, equal to, or greater than its period. By extensive experiments, we show that our proposed analysis significantly improves the acceptance ratio compared with the existing results of the sufficient schedulability test for hybrid scheduling systems.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2016, 26, 3; 683-692
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
An object-oriented approach to simulating human gait motion based on motion tracking
Autorzy:
Tändl, M.
Stark, T.
Erol, N. E.
Löer, F.
Kecskeméthy, A.
Powiązania:
https://bibliotekanauki.pl/articles/930125.pdf
Data publikacji:
2009
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
analiza ruchu
system mięśniowo-szkieletowy
symulacja wieloczłonowa
promieniowanie rentgenowskie
gait/motion analysis
muskuloskeletal system
multibody simulation
MRI
X-ray
motion tracking
Opis:
Accurate bone motion reconstruction from marker tracking is still an open and challenging issue in biomechanics. Presented in this paper is a novel approach to gait motion reconstruction based on kinematical loops and functional skeleton features extracted from segmented Magnetic Resonance Imaging (MRI) data. The method uses an alternative path for concatenating relative motion starting at the feet and closing at the hip joints. From the evaluation of discrepancies between predicted and geometrically identified functional data, such as hip joint centers, a cost function is generated with which the prediction model can be optimized. The method is based on the object-oriented multibody library [...], which has already been successfully applied to the development of industrial virtual design environments. The approach has been implemented in a general gait visualization environment termed Mobile Body.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2009, 19, 3; 469-483
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
A simple scheme for semi-recursive identification of Hammerstein system nonlinearity by Haar wavelets
Autorzy:
Śliwiński, P.
Hasiewicz, Z.
Wachel, P.
Powiązania:
https://bibliotekanauki.pl/articles/330481.pdf
Data publikacji:
2013
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
Hammerstein system
non parametric recursive identification
Haar orthogonal expansion
convergence analysis
numerical stability
system Hammersteina
identyfikacja rekurencyjna nieparametryczna
analiza zbieżności
stateczność numeryczna
Opis:
A simple semi-recursive routine for nonlinearity recovery in Hammerstein systems is proposed. The identification scheme is based on the Haar wavelet kernel and possesses a simple and compact form. The convergence of the algorithm is established and the asymptotic rate of convergence (independent of the input density smoothness) is shown for piecewise-Lipschitz nonlinearities. The numerical stability of the algorithm is verified. Simulation experiments for a small and moderate number of input-output data are presented and discussed to illustrate the applicability of the routine.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2013, 23, 3; 507-520
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Linear-wavelet networks
Autorzy:
Galvao, R. K. H.
Becerra, V. M.
Calado, J. M. F.
Silva, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/907399.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
sieć falkowa
model nieliniowy
analiza regresji
identyfikacja systemu
wavelet networks
nonlinear models
regression analysis
system identification
Opis:
This paper proposes a nonlinear regression structure comprising a wavelet network and a linear term. The introduction of the linear term is aimed at providing a more parsimonious interpolation in high-dimensional spaces when the modelling samples are sparse. A constructive procedure for building such structures, termed linear-wavelet networks, is described. For illustration, the proposed procedure is employed in the framework of dynamic system identification. In an example involving a simulated fermentation process, it is shown that a linear-wavelet network yields a smaller approximation error when compared with a wavelet network with the same number of regressors. The proposed technique is also applied to the identification of a pressure plant from experimental data. In this case, the results show that the introduction of wavelets considerably improves the prediction ability of a linear model. Standard errors on the estimated model coefficients are also calculated to assess the numerical conditioning of the identification process.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2004, 14, 2; 221-232
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Application of Sensitivity Theory to Fuzzy Logic Based Fdi
Autorzy:
Dalton, T.
Klotzek, P.
Frank, P. M.
Powiązania:
https://bibliotekanauki.pl/articles/908289.pdf
Data publikacji:
1999
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
system rozmyty
wyodrębnienie i wykrycie błędu
teoria wrażliwości
analiza reszt
fuzzy systems
fault detection and isolation
fuzzy inference
sensitivity theory
residual analysis
two-tank system
Opis:
This paper describes an application of sensitivity theory to the analysis of a certain class of fuzzy systems which can be used for fault detection and isolation (FDI). The work is divided into three main tasks. The first is the mathematical representation of some class of fuzzy systems. This is followed by an application of sensitivity theory to fuzzy systems based on the approach detailed in the first part. Finally, this method is applied to a fuzzy fault diagnosis scheme for the two-tank system, and the results compared with those achieved by the application of sensitivity theory to a non-fuzzy diagnosis scheme for the same system. Simulation results for the fuzzy and non-fuzzy fault diagnosis schemes are presented, which verify the results obtained via the application of sensitivity theory.
Źródło:
International Journal of Applied Mathematics and Computer Science; 1999, 9, 3; 619-636
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Generalized practical stability analysis of discontinuous dynamical systems
Autorzy:
Zhai, G.
Michel, A. N.
Powiązania:
https://bibliotekanauki.pl/articles/907305.pdf
Data publikacji:
2004
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
układ dynamiczny nieciągły
analiza ilościowa
funkcja Lyapunova
discontinuous dynamical system
quantitative analysis
generalized practical stability
Lyapunov-like function
Opis:
In practice, one is not only interested in the qualitative characterizations provided by the Lyapunov stability, but also in quantitative information concerning the system behavior, including estimates of trajectory bounds, possibly over finite time intervals. This type of information has been ascertained in the past in a systematic manner using the concept of practical stability. In the present paper, we give a new definition of generalized practical stability (abbreviated as GP-stability) and establish some sufficient conditions concerning GP-stability for a wide class of discontinuous dynamical systems. As in the classical Lyapunov theory, our results constitute a Direct Method, making use of auxiliary scalar-valued Lyapunov-like functions. These functions, however, have properties that differ significantly from the usual Lyapunov functions. We demonstrate the applicability of our results by means of several specific examples.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2004, 14, 1; 5-12
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The approximation function of bridge deck vibration derived from the measured eigenmodes
Autorzy:
Sokol, M.
Komorníková, M.
Bacigál, T.
Rodríguez, M. X.
Powiązania:
https://bibliotekanauki.pl/articles/329968.pdf
Data publikacji:
2017
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
eigenmode approximation
eigenmode derivatives
regression spline
spectral analysis
distributed parameter system
krzywa regresji
analiza spektralna
układ o parametrach rozłożonych
Opis:
This article deals with a method of how to acquire approximate displacement vibration functions. Input values are discrete, experimentally obtained mode shapes. A new improved approximation method based on the modal vibrations of the deck is derived using the least-squares method. An alternative approach to be employed in this paper is to approximate the displacement vibration function by a sum of sine functions whose periodicity is determined by spectral analysis adapted for non-uniformly sampled data and where the parameters of scale and phase are estimated as usual by the least-squares method. Moreover, this periodic component is supplemented by a cubic regression spline (fitted on its residuals) that captures individual displacements between piers. The statistical evaluation of the stiffness parameter is performed using more vertical modes obtained from experimental results. The previous method (Sokol and Flesch, 2005), which was derived for near the pier areas, has been enhanced to the whole length of the bridge. The experimental data describing the mode shapes are not appropriate for direct use. Especially the higher derivatives calculated from these data are very sensitive to data precision.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2017, 27, 4; 799-814
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Normalized finite fractional differences: Computational and accuracy breakthroughs
Autorzy:
Stanisławski, R.
Latawiec, K. J.
Powiązania:
https://bibliotekanauki.pl/articles/331334.pdf
Data publikacji:
2012
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
różnica ułamkowa
różnica Grünwalda-Letnikowa
analiza stabilności
system adaptacyjny
fractional difference
Grünwald-Letnikov difference
stability analysis
recursive computation
adaptive systems
Opis:
This paper presents a series of new results in finite and infinite-memory modeling of discrete-time fractional differences. The introduced normalized finite fractional difference is shown to properly approximate its fractional difference original, in particular in terms of the steady-state properties. A stability analysis is also presented and a recursive computation algorithm is offered for finite fractional differences. A thorough analysis of computational and accuracy aspects is culminated with the introduction of a perfect finite fractional difference and, in particular, a powerful adaptive finite fractional difference, whose excellent performance is illustrated in simulation examples.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2012, 22, 4; 907-919
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Health-aware and fault-tolerant control of an octorotor UAV system based on actuator reliability
Autorzy:
Salazar, Jean Carlo
Sanjuan, Adrián
Nejjari, Fatiha
Sarrate, Ramon
Powiązania:
https://bibliotekanauki.pl/articles/329705.pdf
Data publikacji:
2020
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
prognostics and health management
health aware control
fault-tolerant control
reliability analysis
octorotor
UAV system
zarządzanie zdrowiem
sterowanie tolerujące uszkodzenia
analiza niezawodności
Opis:
A major goal in modern flight control systems is the need for improving reliability. This work presents a health-aware and fault-tolerant control approach for an octorotor UAV that allows distributing the control effort among the available actuators based on their health information. However, it is worth mentioning that, in the case of actuator fault occurrence, a reliability improvement can come into conflict with UAV controllability. Therefore, system reliability sensitivity is redefined and modified to prevent uncontrollable situations during the UAV’s mission. The priority given to each actuator is related to its importance in system reliability. Moreover, the proposed approach can reconfigure the controller to compensate actuator faults and improve the overall system reliability or delay maintenance tasks.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2020, 30, 1; 47-59
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On-the-fly diagnosability analysis of bounded and unbounded labeled Petri nets using verifier nets
Autorzy:
Li, B.
Khlif-Bouassida, M.
Toguéyni, A.
Powiązania:
https://bibliotekanauki.pl/articles/330272.pdf
Data publikacji:
2018
Wydawca:
Uniwersytet Zielonogórski. Oficyna Wydawnicza
Tematy:
fault diagnosis
discrete event system
labeled Petri nets
on-the-fly diagnosability analysis
verifier nets
diagnostyka błędu
układ zdarzeń dyskretnych
sieci Petriego
Opis:
This paper considers the problem of diagnosability analysis of discrete event systems modeled by labeled Petri nets (LPNs). We assume that the LPN can be bounded or unbounded with no deadlock after firing any fault transition. Our approach is novel and presents the on-the-fly diagnosability analysis using verifier nets. For a given LPN model, the verifier net and its reachability graph (for a bounded LPN) or coverability graph (for an unbounded LPN) are built on-the-fly and in parallel for diagnosability analysis. As soon as a diagnosability decision is established, the construction is stopped. This approach achieves a compromise between computation limitations due to efficiency and combinatorial explosion and it is useful to implement an engineering approach to the diagnosability analysis of complex systems.
Źródło:
International Journal of Applied Mathematics and Computer Science; 2018, 28, 2; 269-281
1641-876X
2083-8492
Pojawia się w:
International Journal of Applied Mathematics and Computer Science
Dostawca treści:
Biblioteka Nauki
Artykuł

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies