Results 91 to 100 of about 4,538,824 (321)

Numerical radius inequalities

, 2022
We introduce some basic theory about numerical range and numerical radius. Basic inequalities for numerical radius which involve one operator and basic inequalities which involve product of two commutative operators are studied. We then introduce more complex numerical radius inequalities for one operator, finding some upper bounds for the nonnegative ...
openaire   +1 more source

Matricial Radius: A Relation of Numerical radius with Matricial Range

, 2019
It has been shown that if $T$ is a complex matrix, then {\small\begin{align*} (T)&=\frac{1}{n}\sup\left\{|\mathrm{Tr}\ X|;\ X\in W^n(T)\right\}\\ &=\frac{1}{n}\sup\left\{\|X\|_1;\ X\in W^n(T)\right\}\\ &= \sup\left\{ (X);\ X\in W^n(T)\right\} \end{align*} } where $n$ is a positive integer, $ (T)$ is the numerical radius and $W^n(T)$ is
Dehghani, Mahdi, Kian, Mohsen, Sattari, Mostafa   +2 more
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A Robust Adaptive One‐Sample‐Ahead Preview Super‐Twisting Sliding Mode Controller

International Journal of Adaptive Control and Signal Processing, EarlyView.
Block Diagram of the Robust Adaptive One‐Sample‐Ahead Preview Super‐Twisting Sliding Mode Controller. ABSTRACT This article introduces a discrete‐time robust adaptive one‐sample‐ahead preview super‐twisting sliding mode controller. A stability analysis of the controller by Lyapunov criteria is developed to demonstrate its robustness in handling both ...
Guilherme Vieira Hollweg, Paulo Jefferson Dias de Oliveira Evald, Shivam Chaturvedi, Hilton Abilio Gründling, Rodrigo Varella Tambara, Wencong Su   +5 more
wiley   +1 more source

Intermediate-mass-ratio black hole binaries: intertwining numerical and perturbative techniques

, 2010
We describe in detail full numerical and perturbative techniques to compute the gravitational radiation from intermediate-mass-ratio black-hole-binary inspirals and mergers.
Campanelli, Manuela, Lousto, Carlos O., Nakano, Hiroyuki, Zlochower, Yosef   +3 more
core   +1 more source

Upper Bounds for the Numerical Radius of Off-Diagonal 2 × 2 Operator Matrices

Mathematics
We establish multiple novel upper estimates for the numerical radius associated with off-diagonal operator matrices defined on a complex Hilbert space H.
Najla Altwaijry, Silvestru Sever Dragomir   +1 more
doaj   +1 more source

Revisiting Stability Criteria in Ball‐Milled High‐Entropy Alloys: Do Hume–Rothery and Thermodynamic Rules Equally Apply?

Advanced Engineering Materials, Volume 27, Issue 6, March 2025.
The stability criteria affecting the formation of high‐entropy alloys, particularly focusing in supersaturated solid solutions produced by mechanical alloying, are analyzed. Criteria based on Hume–Rothery rules are distinguished from those derived from thermodynamic relations. The formers are generally applicable to mechanically alloyed samples.
Javier S. Blázquez, Alejandro F. Manchón‐Gordón, Antonio Vidal‐Crespo, Rafael Caballero‐Flores, Jhon J. Ipus, Clara F. Conde   +5 more
wiley   +1 more source

New generalized numerical radius inequalities for Hilbert space operators

Journal of Inequalities and Applications
We define generalized real and imaginary parts of an operator, as well as the generalized w h , g ( ⋅ ) $w_{h,g}(\cdot )$ numerical radius, which reduces to the t-weighted numerical radius for suitable functions h , g $h,g$ .
Fuad Kittaneh, Vuk Stojiljković
doaj   +1 more source

Bistable Mechanisms 3D Printing for Mechanically Programmable Vibration Control

Advanced Engineering Materials, EarlyView.
This work introduces a 3D‐printed bistable mechanism integrated into tuned mass dampers (TMDs) for mechanically adaptive passive vibration suppression. Through optimized geometry, the bistable design provides adaptable vibration reduction across a broad range of scenarios, achieving effective vibration mitigation without complex controls or external ...
Ali Zolfagharian, Frédéric Demoly, Mohammad Lakhi, Bernard Rolfe, Mahdi Bodaghi   +4 more
wiley   +1 more source

Characterization of Defect Distribution in an Additively Manufactured AlSi10Mg as a Function of Processing Parameters and Correlations with Extreme Value Statistics

Advanced Engineering Materials, EarlyView.
Predicting extreme defects in additive manufacturing remains a key challenge limiting its structural reliability. This study proposes a statistical framework that integrates Extreme Value Theory with advanced process indicators to explore defect–process relationships and improve the estimation of critical defect sizes. The approach provides a basis for
Muhammad Muteeb Butt, Varma Kvvssn, Hossein Laieghi, Zia Uddin, Peyman Ansari, E. Kıvanç Sadak, Can Barış Toprak, Hüseyin Kızıl, Enrico Salvati   +8 more
wiley   +1 more source

Computing the numerical radius

Linear Algebra and its Applications, 1996
The paper deals with the numerical calculation of the numerical radius of a complex matrix. The derived methods consist mainly of matrix-vector multiplications, being based on the power method for calculating the largest eigenvalue (in modulus) of a Hermitian matrix. Computational tests are given to show the efficiency of the proposed algorithm.
openaire   +1 more source