This paper presents a theoretical derivation and computer simulation of an optimal speed controller for a brushless dc motor using feedback from a linear model running in parallel with the inverter-fed model. The intent of the feedback from the linear model is to eliminate torque ripples from the inverter drive. A nonlinear model of such a motor, transformed into a linear model by a local diphe...

frozen section and touch imprint cytology are important diagnostic procedures for surgeons during operation and must be accurate if the patient is to receive maximum benefit. to assess the accuracy of intraoperative pathologic consultation including frozen section and touch imprint cytology during a five year period (1995- 2000), a retrospective survey of 1000 consecutive cases of frozen sectio...

ultrasound images suffer of multiplicative noise named speckle. different de-speckling algorithms run either in spatial domain or in transformed domain. in this paper, an adaptive filter in spatial domain according to assume the nakagami distribution as the statistic of log-compressed ultrasound images is used. for de-speckling in transformed domain, the non-sub sampled shearlet transform is us...

The finite section method is a classical scheme to approximate the solution of an infinite system of linear equations. We present quantitative estimates for the rate of the convergence of the finite section method on weighted `-spaces. Our approach uses recent results from the theory of Banach algebras of matrices with off-diagonal decay. Furthermore, we demonstrate that Banach algebra theory p...

Quasidiagonal operators on a Hilbert space are a large and important class (containing all self-adjoint operators for instance). They are also perfectly suited for study via the finite section method (a particular Galerkin method). Indeed, the very definition of quasidiagonality yields finite sections with good convergence properties. Moreover, simple operator theory techniques yield estimates ...

Section 2 concerns the ways in which teaching and learning at a distance is being transformed in various international and practical contexts. Arguably, distance education has been characterised by transformation since its earliest correspondence days through to the integration of online media. Tony Bates pursues this latter theme in his opening chapter for the section where the range of new me...

A new method for exact quantization of general bound Hamiltonian systems is presented. It is the quantum analogue of the classical Poincaré Surface Of Section (SOS) reduction of classical dynamics. The quantum Poincaré mapping is shown to be the product of the two generalized (non-unitary but compact) on-shell scattering operators of the two scattering Hamiltonians which are obtained from the o...

Abstract In this work, the Mellin transform method was used to obtain solutions for the stress field components in two dimensional (2D) elasticity problems in terms of plane polar coordinates. the Mellin transformation was applied to the biharmonic stress compatibility equation expressed in terms of the Airy stress potential function, and the boundary value problem transformed to an algebraic  ...