Results 31 to 40 of about 77,145 (154)

A constructive presentation of rigged Hilbert spaces [PDF]

Journal of Physics: Conference Series, 2015
9 pages, 7th Int. Workshop DICE2014, Sept. 15-19, 2014, Castiglioncello (Italy)
E. Celeghini
openalex   +5 more sources

Resonances and the extension of dynamics to rigged Hilbert space

Computers & Mathematics with Applications, 1997
AbstractWe propose a unified operator theoretic formulation of resonances and resonance states in rigged Hilbert space. Our approach shows how resonances are the basis for the extension of dynamics for unstable systems, and in a synthesis and a generalization of the work of the Brussels/Austin groups directed by Prigogine with the work of Bohm and ...
I. Antoniou, L. Dmitrieva, Y. Kuperin, Y. Melnikov   +3 more
semanticscholar   +3 more sources

ON ULTRAPRODUCTS, THE SPECTRAL THEOREM AND RIGGED HILBERT SPACES

The Journal of Symbolic Logic
Abstract We start by showing how to approximate unitary and bounded self-adjoint operators by operators in finite dimensional spaces. Using ultraproducts we give a precise meaning for the approximation. In this process we see how the spectral measure is obtained as an ultralimit of counting measures that arise naturally from the finite dimensional ...
Åsa Hirvonen, Tapani Hyttinen
openalex   +4 more sources

Irreversible evolution of a wave packet in the rigged-Hilbert-space quantum mechanics [PDF]

, 2016
It is well known that a state with complex energy cannot be the eigenstate of a self-adjoint operator, such as the Hamiltonian. Resonances, i.e., states with exponentially decaying observables, are not vectors belonging to the conventional Hilbert space.
G. Marcucci, C. Conti
semanticscholar   +1 more source

A shape optimization algorithm based on directional derivatives for three‐dimensional contact problems

International Journal for Numerical Methods in Engineering, Volume 124, Issue 13, Page 2935-2964, 15 July 2023., 2023
Abstract This work deals with shape optimization for contact mechanics. More specifically, the linear elasticity model is considered under the small deformations hypothesis, and the elastic body is assumed to be in contact (sliding or with Tresca friction) with a rigid foundation.
Bastien Chaudet‐Dumas
wiley   +1 more source

Manipulation of stator current signature for rotor asymmetries fault diagnosis of wound rotor induction machine

IET Science, Measurement &Technology, Volume 16, Issue 9, Page 523-532, November 2022., 2022
Abstract In this paper, a new technique based on the manipulation of stator current signature for induction machines fault diagnosis is introduced. The goal of the proposed method is to demodulate the characteristic frequencies from supply frequency and preserve the information of the supply frequency and its harmonics.
Mohammad Hoseintabar Marzebali, Vahid Abolghasemi, Saideh Ferdowsi, Reza Bazghandi   +3 more
wiley   +1 more source

Data mining in predictive maintenance systems: A taxonomy and systematic review

WIREs Data Mining and Knowledge Discovery, Volume 12, Issue 5, September/October 2022., 2022
Predictive Maintenance from a Data Mining perspective: this review analyzes the most significant predictive maintenance (PdM) contributions in recent years from Data Mining (DM) perspective. An exhaustive study is carried out to determine the most used DM techniques for solving each specific PdM problem.
Aurora Esteban, Amelia Zafra, Sebastián Ventura   +2 more
wiley   +1 more source

Generalized boundary triples, II. Some applications of generalized boundary triples and form domain invariant Nevanlinna functions

Mathematische Nachrichten, Volume 295, Issue 6, Page 1113-1162, June 2022., 2022
Abstract The paper is a continuation of Part I and contains several further results on generalized boundary triples, the corresponding Weyl functions, and applications of this technique to ordinary and partial differential operators. We establish a connection between Post's theory of boundary pairs of closed nonnegative forms on the one hand and the ...
Volodymyr Derkach, Seppo Hassi, Mark Malamud   +2 more
wiley   +1 more source

An Improved Bearing Fault Diagnosis Model of Variational Mode Decomposition Based on Linked Extension Neural Network

Computational Intelligence and Neuroscience, Volume 2022, Issue 1, 2022., 2022
In bearing fault diagnosis, due to the insufficient obtained supervised data and the inevitable noise contained in the vibration signals, the problem of clustering bearing fault diagnosis with imbalanced data containing noise is caused. Thanks to the ability to quickly and fully learn boundary information in small samples, the extension neural network ...
Tichun Wang, Jiayun Wang, Huihua Chen
wiley   +1 more source

An Intelligent Fault Diagnosis Based on Adversarial Generating Module and Semi‐supervised Convolutional Neural Network

Computational Intelligence and Neuroscience, Volume 2022, Issue 1, 2022., 2022
Aiming at the existing problems in machinery monitoring data such as high cost of labeling and lack of typical failure samples, this paper launches a research on the semi‐supervised‐style intelligent fault diagnosis. Taking a great mount of unlabeled data and only a small quantity of labeled data as inputs, a novel fault diagnosis framework based on ...
Qing Ye, Changhua Liu, Rodolfo E. Haber
wiley   +1 more source