We give a brief account of the numerical radius of a linear bounded operator on a Hilbert space and some of its better-known properties. Both finiteand infinitedimensional aspects are discussed, as well as applications to stability theory of finite-difference approximations for hyperbolic initial-value problems. 1. DEFINITION, BOUNDS, AND EVALUATION Let H be a Hilbert space over the complex fie...

In this paper, we examine the behavior of internal Kelvin waves on an f-plane in finitedifference models using the Arakawa C-grid. The dependence of Kelvin wave phase speed on offshore grid resolution and propagation direction relative to the numerical grid is illustrated by numerical experiments for three different geometries: (1) Kelvin wave propagating along a straight coastline; (2) Kelvin ...

Recently, Uhlig [Numer. Algorithms, 52(3):335-353, 2009] proposed open questions about the ratios between the spectral norm, the numerical radius and the spectral radius of a square matrix. In this note, we provide some observations to answer these questions. Keywords—Spectral norm, Numerical radius, Spectral radius, Ratios

In this work, an improvement of Hölder–McCarty inequality is established. Based on that, several refinements the generalized mixed Schwarz are obtained. Consequently, some new numerical radius inequalities proved. New for $$n\times n$$ matrix Hilbert space operators proved as well. Some earlier results were in literature also given. presented refined and it shown to be better than literature.

An 18-year-old girl presented with an osteoid osteoma in the ulnar side of the cortex of the distal radius extending into the distal radioulnar joint. The osteoid osteoma was removed from the distal radius at surgery. The patient’s symptoms were dramatically improved the day after surgery. A high concentration of prostaglandin E2 (PGE2) was seen in the joint and surrounding soft tissues, and cy...

production and preparation of many parts of the aircraft body including wings with long length, smooth form, and large radius of curvature are amongst the most important challenges in this industry. in this paper, the effective factors in the rubber pad forming method on a pieces contain curvature radius have been investigated by finite element method. the effect of variables such as curvature ...