Ahmed Attia

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This paper presents some design approaches to hybrid control systems combining conventional control techniques with fuzzy logic and neural networks. Such a mixed implementation leads to a more effective control design with improved system performance and robustness. While conventional control allows different design objectives such as steady state and(More)
The optimal designs and statistical inference of accelerated life tests under type-I are studied for constant stress-accelerated life tests CSALTs. It is assumed that the lifetime at design stress has generalized logistic distribution. The scale parameter of the lifetime distribution at constant stress levels is assumed to be an inverse power law function(More)
This paper constructs an ensemble-based sampling smoother for four-dimensional data assimilation using a Hybrid/Hamiltonian Monte-Carlo approach. The smoother samples efficiently from the posterior probability density of the solution at the initial time. Unlike the well-known ensemble Kalman smoother, which is optimal only in the linear Gaussian case, the(More)
Hybrid Monte-Carlo (HMC) sampling smoother is a fully non-Gaussian four-dimensional data assimilation algorithm that works by directly sampling the posterior distribution formulated in the Bayesian framework. The smoother in its original formulation is computationally expensive due to the intrinsic requirement of running the forward and adjoint models(More)
The intent of this study was to evaluate relative and absolute reliability of the 20-s anaerobic test (WAnT20) versus the WAnT30 and to verify how far the various indices of the 30-s Wingate anaerobic test (WAnT30) could be predicted from the WAnT20 data in male athletes. The participants were Exercise Science majors (age: 21.5±1.6 yrs, stature: 0.183±0.08(More)
This descriptive study investigates in a rabbit model of atherosclerosis (i) the extent of atherogenesis induced by cyclosporine A (CsA) or hyperlipidemia alone or in combination and (ii) whether thymoquinone (TQ), a known herbal antioxidant, offers protection against these effects. New Zealand White female rabbits were assigned to five groups of six(More)
Accelerated life testing is a method for estimating the reliability of products at normal use conditions from the failure data obtained at the severe conditions. In this paper, constant-stress accelerated life testing is considered when the lifetime of a product follows a two-parameter Birnbaum-Saunders distribution. Based on type-II censoring. A certain(More)
This paper presents a fully non-Gaussian version of the Hamiltonian Monte Carlo (HMC) sampling filter. The Gaussian prior assumption in the original HMC filter is relaxed. Specifically , a clustering step is introduced after the forecast phase of the filter, and the prior density function is estimated by fitting a Gaussian Mixture Model (GMM) to the prior(More)