We describe a fast algorithm to compute the real structured stability radius with respect to the open left-half plane or the open unit disk. It is based on a recent formula proved by Qiu et al. (Automatica, vol. 31, pp. 879-890, 1995) and the well-known correspondence between the singular values of a transfer function matrix and the imaginary eigenvalues of a related Hamiltonian matrix. Numeric...

Various concepts of orthogonality on the real line are reviewed that arise in connection with quadrature rules. Orthogonality relative to a positive measure and Gauss-type quadrature rules are classical. More recent types of orthogonality include orthogonality relative to a sign-variable measure, which arises in connection with Gauss-Kronrod quadrature, and power (or implicit) orthogonality enc...

The stability radius of a matrix polynomial P (λ) relative to an open region Ω of the complex plane and its relation to the numerical range of P (λ) are investigated. Using an expression of the stability radius in terms of λ on the boundary of Ω and ‖P (λ)−1‖2, a lower bound is obtained. This bound for the stability radius involves the distances of Ω to the connected components of the numerical...

AIM To evaluate the reliability of pronator quadratus fat pad sign to detect distal radius fracture and to predict its severity. METHODS Retrospectively we identified 89 consecutive patients (41 female, mean age 49 ± 18 years) who had X-ray (CR) and computed tomography (CT) within 24 h following distal forearm trauma. Thickness of pronator quadratus fat pad complex (PQC) was measured using la...

Fluctuation Analysis (FA) and specially Detrended Fluctuation Analysis (DFA) are techniques commonly used to quantify correlations and scaling properties of complex time series such as the observable outputs of great variety of dynamical systems, from Economics to Physiology. Often, such correlated time series are analyzed using the magnitude and sign decomposition, i.e., by using FA or DFA to ...

Salmonella osteomyelitis of the radius in a healthy individual is very rare. We present such a case involving the distal radius of a healthy 23-year-old man without underlying disease or possible episode. He had right wrist pain for approximately 3 years, and osteolytic lesion was seen in the right distal radius. He underwent surgical treatment, and salmonella was isolated from pus in the lesio...

Let ‎X be an ‎‎n-‎‎‎‎‎‎square complex matrix with the ‎Cartesian decomposition ‎‎X = A + i ‎B‎‎‎‎‎, ‎where ‎‎A ‎and ‎‎B ‎are ‎‎‎n ‎‎times n‎ ‎Hermitian ‎matrices. ‎It ‎is ‎known ‎that ‎‎$Vert X Vert_p^2 ‎leq 2(Vert A Vert_p^2 + Vert B Vert_p^2)‎‎‎$, ‎where ‎‎$‎p ‎‎geq 2‎$‎ ‎and ‎‎$‎‎Vert . Vert_p$ ‎is ‎the ‎Schatten ‎‎‎‎p-norm.‎ ‎‎ ‎‎In this paper‎, this inequality and some of its improvements ...

We present a general theory of liquid crystals under inhomogeneous electric field in a Ginzburg-Landau scheme. The molecular orientation can be deformed by electric field when the dielectric tensor is orientation dependent. We then investigate the influence of a charged particle on the orientation order in a nematic state. The director is aligned either along or perpendicular to the local elect...