Results 81 to 90 of about 69,047 (280)
Characteristics of axisymmetric viscous incompressible flow passing a torus rotating about its centerline [PDF]
Songklanakarin Journal of Science and Technology (SJST), 2016 The present numerically investigates the axisymmetric flow past a rotating torus in a viscous incompressible fluid. The surface of the torus rotates with constant velocity around its centerline.
Pairin Suwannasri
doaj
Some Inequalities for (α,β)-Normal Operators in Hilbert Spaces
, 2007 An operator T is called (α,β)-normal (0 ≤ α ≤ 1 ≤ β) if α²T*T ≤ TT* ≤ β²T*T. In this paper, we establish various inequalities between the operator norm and its numerical radius of (α,β)-normal operators in Hilbert spaces.
Dragomir, Sever S +1 more
core
Maps preserving the joint numerical radius distance of operators
, 2012 Denote the joint numerical radius of an m-tuple of bounded operators A=(A1,…,Am) by w(A). We give a complete description of maps f satisfying w(A-B)=w(f(A)-f(B)) for any two m-tuples of operators A=(A1,…,Am) and B=(B1,…,Bm).
Li, Chi-Kwong, Poon, Edward
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Development of inequality and characterization of equality conditions for the numerical radius
, 2021 Let $A$ be a bounded linear operator on a complex Hilbert space and $\Re(A)$ ( $\Im(A)$ ) denote the real part (imaginary part) of A. Among other refinements of the lower bounds for the numerical radius of $A$, we prove that \begin{eqnarray*} w(A)&\geq &\
Paul, Kallol, Bhunia, Pintu
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Advanced Engineering Materials, EarlyView.This study demonstrates an efficient recycling route for out‐of‐spec AlSi10Mg atomized powders through compaction and arc remelting followed by suction casting. By correlating compaction load, cooling rate, and resulting microstructure, we show that intermediate pressures (50–80 kN) and rapid cooling refine dendrites, reduce porosity, and enhance ...
Mila Christy de Oliveira +4 more
wiley +1 more source
Scientific ReportsWhen roadways in strong mine pressure working faces traverse collapse columns, the complex stress redistribution frequently induces surrounding rock instability and support structure failure.
Hai Rong +4 more
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The numerical range of derivations
, 1989 Let p, q, n be integers satisfying 1 ≤ p ≤ q ≤ n. The (p, q)-numerical range of an n×n complex matrix A is defined by Wp,q(A) = {Ep((UAU*)[q]): U unitary}, where for an n×n complex matrix X, X[q] denotes its q×q leading principal submatrix and Ep(X[q ...
Li, Chi-Kwong +3 more
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A Compact Spin‐Coated Graphene UWB Antenna for Breast Tumor Detection
Advanced Engineering Materials, EarlyView.A compact, spin‐coated graphene ultra‐wideband patch antenna designed for breast tumor detection, capable of distinguishing between malignant and benign tumors. This innovative antenna can serve as an effective initial screening tool, particularly in resource‐limited settings such as rural areas, where access to advanced medical equipment like MRI and ...
Raja Rashidul Hasan +9 more
wiley +1 more source
A note on convexity of sections of quaternionic numerical range
, 2019 The quaternionic numerical range of matrices over the ring of quaternions is not necessarily convex. We prove Toeplitz-Hausdorff like theorem: for any given quaternionic matrix, every section of its quaternionic numerical range is convex. We provide some
P. Santhosh Kumar, Santhosh Kumar, P.
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, 2022 We employ tools and techniques from multivariable operator theory to obtain new proofs and extensions of well known inequalities regarding the norm and the numerical radius of elementary operators defined on the C⁎ role= presentation style= box-sizing:
Curto, Raul E. +2 more
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