We study the spectrum of a periodic self-adjoint operator on the axis perturbed by a small localized nonself-adjoint operator. It is shown that the continuous spectrum is independent of the perturbation, the residual spectrum is empty, and the point spectrum has no finite accumulation points. We address the existence of the embedded eigenvalues. We establish the necessary and sufficient conditi...

The dynamic characterization of a set of gold micro beams by electrostatic excitation in presence of residual stress gradient has been studied experimentally. A method to determine the micro-cantilever residual stress gradient by measuring the deflection and curvature and then identifying the residual stress model by means of frequency shift behaviour is presented. A comparison with different n...

BACKGROUND AND PURPOSE Although the spectrum of perinatal white matter injury (WMI) in preterm infants is shifting from cystic encephalomalacia to milder forms of WMI, the factors that contribute to this changing spectrum are unclear. We hypothesized that the variability in WMI quantified by immunohistochemical markers of inflammation could be correlated with the severity of impaired blood oxyg...

The purpose of this paper is threefold: first to mainly review several recent results concerning the fine spectrum of the operator ∆v over the sequence spaces c and lp, where 1 < p < ∞; second to provide some new results concerning the residual spectrum and the continuous spectrum of the operator ∆v over the sequence spaces c and lp; and third to modify the definition of the operator ∆v and to ...

Abstract Residual coherence is a graphical tool for selecting potential second-order interaction terms as functions of single time series and its lags. This paper extends the notion residual to account multiple series. Moreover, an alternative criterion, integrated spectrum, proposed facilitate this selection. A financial market application shows that new insights can be gained regarding implie...

there are many different ways to subdivide the spectrum of a bounded linear operator; some of them aremotivated by applications to physics (in particular, quantum mechanics). in this study, the relationship betweenthe subdivisions of spectrum which are not required to be disjoint and goldberg's classification are given.moreover, these subdivisions for some summability methods are studied.

In this note we consider Kotani eigenstates of one-dimensional Schrödinger operators with ergodic potential. We show that if the spectrum, restricted to an interval, has zero Lyapunov exponents and is a Cantor set, then for a residual subset of energies, Kotani eigenstates do not exist. In particular, we show that the quasi-periodic Schrödinger operators whose Schrödinger quasi-periodic cocycle...

The handsfree mode is convenient when using a mobile phone in a vehicle. This mode brings the microphone away from the talker’s mouth. As a consequence the speech signal picked up has low Signal to Noise Ratio. Thus, to improve the SNR a noise reduction method is employed. The proposed method is an improvement of the well-known spectral subtraction method which uses one SNR-dependent gain funct...

The acoustic data remotely measured by microphones are widely used to investigate monitoring and diagnose integrity of ball bearing in rotational machines. Early fault diagnosis is very difficult for acoustic emission. We propose a new method using a cross-correlation of frequency spectrum to classify various faults with fine grit. Principal component analysis (PCA) is used to separate the prim...

This paper describes an excitation model based on amplitude spectrum for hidden Markov model (HMM)-based speech synthesis system (HTS). Residual signal obtained from inverse filtering is decomposed into periodic and aperiodic spectrums in frequency domain. Amplitude spectrum of half pitch period length is reserved as periodic component in synthesis stage and zero-phase criterion and pitch synch...