Search results for "Control system"
showing 10 items of 971 documents
Non-fragile fuzzy control design for nonlinear time-delay systems
2013
In this paper, a non-fragile fuzzy control design is proposed for a class of nonlinear systems with mixed discrete and distributed time delays. The Takagi and Sugeno (T-S) fuzzy set approach is applied to the modelling of the nonlinear dynamics, and a T-S fuzzy model is constructed, which can represent the nonlinear system. Then, based on the fuzzy linear model, a fuzzy linear controller is developed to stabilize the nonlinear system. The control law is obtained to ensure stochastically exponentially stability in the mean square. The sufficient conditions for the existence of such a control are proposed in terms of certain linear matrix inequalities.
Stabilization for a class of nonlinear networked control systems via polynomial fuzzy model approach
2014
This article is concerned with the stabilization problem for nonlinear networked control systems which are represented by polynomial fuzzy models. Two communication features including signal transmission delays and data missing are taken into account in a network environment. To solve the network-induced communication problems, a novel sampled-data fuzzy controller is designed to guarantee that the closed-loop system is asymptotically stable. The stability and stabilization conditions are presented in terms of sum of squares SOS, which can be numerically solved via SOSTOOLS. Finally, a simulation example is provided to demonstrate the feasibility of the proposed method. © 2014 Wiley Periodi…
Observer-based finite-time control for discrete fuzzy jump nonlinear systems with time delays
2013
This paper investigates the problem of observer-based finite-time H∞ control for a family of discrete jump nonlinear systems with time delays represented by Takagi-Sugeno (T-S) model. The main contribution of this paper is to design an observer-based finite-time H∞ controller such that the resulting closed-loop system is stochastic finite-time bounded and satisfies a prescribed H∞ disturbance attenuation level over the given finite-time interval. Sufficient criteria on stochastic finite-time H∞ stabilization via observer-based fuzzy state feedback are provided for the solvability of the problem, which can be tackled by a feasibility problem in terms of linear matrix inequalities. A simulati…
Finite-time stabilization for discrete fuzzy jump nonlinear systems with time delays
2013
This paper is concerned with the problem of finite-time H∞ control for a class of discrete-time Markovian jump nonlinear systems with time delays represented by Takagi-Sugeno (T-S) model. First, by using fuzzy stochastic Lyapunov-Krasovskii functional approach, sufficient conditions are derived such that the resulting close-loop system is stochastic finite-time bounded and satisfies a prescribed H∞ disturbance attenuation level in a given finite-time interval. Second, sufficient criteria on stochastic finite-time H∞ stabilization via fuzzy state feedback are provided, and the fuzzy state feedback controller is designed by solving an optimization problem in terms of linear matrix inequalitie…
Shell-model calculation of isospin-symmetry breaking correction to superallowed Fermi beta-decay
2016
We investigate the radial-overlap part of the isospin-symmetry breaking correction to superallowed $0^+\to 0^+$-decay using the shell-model approach similar to that of Refs. [1, 2]. The 8 sd-shell emitters with masses between $A=22$ and $A=38$ have been re-examined. The Fermi matrix element is evaluated with realistic spherical single-particle wave functions, obtained from spherical Woods-Saxon (WS) or Hartree-Fock (HF) potentials, fine-tuned to reproduce the experimental data on charge radii and separation energies for nuclei of interest. The elaborated adjustment procedure removes any sensitivity of the correction to a specific parametrisation of the WS potential or to various versions of…
Testing microscopically derived descriptions of nuclear collectivity: Coulomb excitation of Mg-22
2018
Many-body nuclear theory utilizing microscopic or chiral potentials has developed to the point that collectivity might be dealt with in an {\it ab initio} framework without the use of effective charges; for example with the proper evolution of operators, or alternatively, through the use of an appropriate and manageable subset of particle-hole excitations. We present a precise determination of $E2$ strength in $^{22}$Mg and its mirror $^{22}$Ne by Coulomb excitation, allowing for rigorous comparisons with theory. No-core symplectic shell-model calculations were performed and agree with the new $B(E2)$ values while in-medium similarity-renormalization-group calculations consistently underpre…
Methodologies for the Statistical Analysis of Memory Response to Radiation
2016
International audience; Methodologies are proposed for in-depth statistical analysis of Single Event Upset data. The motivation for using these methodologies is to obtain precise information on the intrinsic defects and weaknesses of the tested devices, and to gain insight on their failure mechanisms, at no additional cost. The case study is a 65 nm SRAM irradiated with neutrons, protons and heavy ions. This publication is an extended version of a previous study.
Performance of the AX-PET Demonstrator
2011
The goal of the AX-PET project is to build and test a demonstrator for a high resolution, high sensitivity PET scanner, based on a novel geometrical concept of long axially oriented crystals. The demonstrator comprises two PET modules used in coincidence. The two modules have been constructed and characterized (both individually and in coincidence) in dedicated test setups, with point-like sources. Good performance in terms of energy, spatial and timing resolution have been demonstrated. First measurements with extended phantoms filled with FDG-radiotracers have been recently performed.
Collisional ionization as a sensitive detection scheme in collinear laser-fast-beam spectroscopy
1986
Abstract State-selective collisional ionization of fast atomic beams is used to detect optical pumping. Counting of these ions is superior in sensitivity by several orders of magnitude to the conventional fluorescence detection, provided that the energy levels involved in the optical pumping process are sufficiently well separated. A straightforward application is envisaged in the collinear laser-fast-beam spectroscopy of rare-gas isotopes far from stability of which only very weak beams are available from on-line isotope separators.
Adding pseudo-observables to the four-lepton experimentalist’s toolbox
2018
The "golden" channel, in which the newly-discovered Higgs boson decays to four leptons by means of intermediate vector bosons, is important for determining the properties of the Higgs boson and for searching for subtle new physics effects. Different approaches exist for parametrizing the relevant Higgs couplings in this channel; here we relate the use of pseudo-observables to methods based on specifying the most general amplitude or Lagrangian terms for the $HVV$ interactions. We also provide projections for sensitivity in this channel in several novel scenarios, illustrating the use of pseudo-observables, and analyze the role of kinematic distributions and (ratios of) rates in such $H\to4\…