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The vulnerability of Zigbee technology to noise in an electricity substation environment is assessed. Substation noise obtained from a measurement campaign is modelled as a Symmetric α-Stable process. The parameters of the model are estimated from the measurements and the resulting model is used to investigate the likely BER performance of Zigbee technology(More)
In this paper, we propose an original strategy for estimating and reconstructing monocomponent signals having a high nonstationarity and long-time duration. We locally apply to short-time duration intervals the strategy developed in our previous work about nonstationary short-time signals. This paper describes a nonsequential time segmentation that provides(More)
The aim of this paper is Bayesian estimation of the parameters of a polynomial phase signal. This problem , encountered i n r adar systems for example, is usually solved using a time-frequency analysis or phase-only algorithms, see [4] for a detailed introduction. A Bayesian approach using Markov chain Monte Carlo (MCMC) methods for estimating a posteriori(More)
— The problem of estimating nonstationary signals has been considered in many previous publications. In this paper we propose an alternative algorithm in order to accurately estimate AM/FM 1 signals. Only single component signals are considered. We perform local polynomial modeling on short time segments using a nonsequential strategy. The degree of(More)
We use reversible jump Markov c hain Monte Carlo MCMC methods to address the problem of order and parameters estimation of noisy polynomial-phase signals within a Bayesian framework. As posterior distributions of the parameters are not tractable, MCMC methods are used to simulate them. EEcient model jumping is achieved by proposing model space moves from(More)
We consider the modeling of non-stationary discrete signals whose amplitude and frequency are assumed to be nonlinearly modulated over very short-time duration. We investigate the case where both instantaneous amplitude and frequency can be approximated by orthonormal polynomials. Previous works dealing with polynomial approximations refer to orthonormal(More)
In previous published works [8, 3], we have studied the estimation of nonstationary monocomponent signals on short time-windows. Both of the instantaneous amplitude and frequency (IA/ IF) were modeled by polynomial functions. The maximization of the likelihood function was achieved by using a stochastic optimization technique: the Simulated Annealing (SA).(More)
OBJECTIVE To investigate whether the recurrence of infection by Plasmodium falciparum in patients from the Brazilian Amazon was caused by an inadequate exposure to quinine. METHODS A retrospective study was carried out using blood samples from patients with slide-confirmed infection by P. falciparum, classified according to the parasitological response(More)
One of the most widely used techniques for obtaining information on the health state of three-phase induction machines is based on the processing of stator current. In fact, in the case of steady state operations, anomalous current spectral components, that increase if a fault occurs, allow to diagnose the presence and, in some case, the type of fault. In(More)