Search results for "Estimation"
showing 10 items of 924 documents
Overview of Other Results and Open Problems
2014
This chapter presents an overview of results related to error control methods, which were not considered in previous chapters. In the first part, we discuss possible extensions of the theory exposed in Chaps. 3 and 4 to nonconforming approximations and certain classes of nonlinear problems. Also, we shortly discuss some results related to explicit evaluation of modeling errors. The remaining part of the chapter is devoted to a posteriori estimates of errors in iteration methods. Certainly, the overview is not complete. A posteriori error estimation methods are far from having been fully explored and this subject contains many unsolved problems and open questions, some of which we formulate …
Linear parameter estimation and predictive constrained control of wiener/hammerstein systems
2003
Abstract A new, analytical, orthonormal basis functions (OBF)-based design methodology for adaptive predictive constrained control of open-loop stable, possibly nonminimum phase, time-varying Wiener and Hammerstein systems is presented. A linear adaptive least-squares parameter estimation algorithm is applied both to a nonlinear static part and a linear dynamic, OBF-modeled factor of the Wiener/Hammerstein system. A notion of inverse systems is crucial for linear estimation of both Wiener and Hammerstein systems, with in verses of the nonlinear or linear parts respectively involved. The adaptive estimator is coupled with a simple but robust, predictive control strategy called Extended Horiz…
0.1-10 MeV Neutron Soft Error Rate in Accelerator and Atmospheric Environments
2021
Neutrons with energies between 0.1-10 MeV can significantly impact the Soft Error Rate (SER) in SRAMs manufactured in scaled technologies, with respect to high-energy neutrons. Their contribution is evaluated in accelerator, ground level and avionic (12 km of altitude) environments. Experimental cross sections were measured with monoenergetic neutrons from 144 keV to 17 MeV, and results benchmarked with Monte Carlo simulations. It was found that even 144 keV neutrons can induce upsets due to elastic scattering. Moreover, neutrons in the 0.1-10 MeV energy range can induce more than 60% of the overall upset rate in accelerator applications, while their contribution can exceed 18% in avionics.…
The Hu-Washizu variational principle for the identification of imperfections in beams
2008
This paper presents a procedure for the identification of imperfections of structural parameters based on displacement measurements by static tests. The proposed procedure is based on the well-known Hu–Washizu variational principle, suitably modified to account for the response measurements, which is able to provide closed-form solutions to some inverse problems for the identification of structural parameter imperfections in beams. Copyright © 2008 John Wiley & Sons, Ltd.
MUSIC-based modal channel estimation for wideband OFDM-OQAM
2008
Orthogonal frequency division multiplexing based on offset quadrature amplitude modulation (OFDM-OQAM) over wideband frequency selective multipath channels suffers from inter-symbol interference (ISI) and inter-carrier interference (ICI) that degrade its performance. Channel estimation and equalization are needed to combat these interferences. In this paper a novel channel estimator for passband OFDM-OQAM signaling over wideband multipath channels, which is based on multiple signal classification (MUSIC) with the Spatial Smoothing technique is presented. Numerical simulation results are presented in the low number of subcarriers, i.e. wideband, scenario.
Object Recognition and Modeling Using SIFT Features
2013
In this paper we present a technique for object recognition and modelling based on local image features matching. Given a complete set of views of an object the goal of our technique is the recognition of the same object in an image of a cluttered environment containing the object and an estimate of its pose. The method is based on visual modeling of objects from a multi-view representation of the object to recognize. The first step consists of creating object model, selecting a subset of the available views using SIFT descriptors to evaluate image similarity and relevance. The selected views are then assumed as the model of the object and we show that they can effectively be used to visual…
Sustainable Method Using Filtering Techniques for a Fermentation Process State Estimation
2020
Winemaking is concerned about sustainable energy availability that implies new methods for process monitoring and control. The aim of this paper is to realize a comparative analysis of the possibilities offered using estimation techniques, balances, and filtering techniques such as the Kalman filter (KF) and the extended Kalman filter (EKF), to obtain indirect information about the alcoholic fermentation process during winemaking. Thus, an estimation solution of the process variables in the exponential growing phase is proposed, using an extended observer. In addition, two estimation solutions of this process with the EKF and an estimation of the decay phase of the fermentation process are …
Effects of Interrater Reliability of Psychopathologic Assessment on Power and Sample Size Calculations in Clinical Trials
2002
Although rater training is increasingly used to improve the quality of the investigated outcome parameters, the reliability of assessments is not perfect. Thus, empirical reliability estimates should be used instead of theoretically assumed perfect reliability. Implications of the reliability of psychiatric assessments for sample size and power calculations in clinical trials are presented. The theoretical basis of sample size and power calculations using empirical reliability scores is delineated. Examples from contemporary research on schizophrenia and depression are used to illustrate several implications for study design and interpretation of results. The tremendous impact of the lack o…
Ontology mapping specification in description logics for cooperative systems
2006
Le developpement rapide du Web semantique est lie a la specification de plus en plus d'ontologies. Celles-ci permettent de modeliser des connaissances agreees par des communautes de personnes concernant des domaines ou des tâches specifiques. Le meme domaine decrit par deux communautes distinctes sera modelise de facon differente. Les systemes cooperatifs visent a rendre les informations provenant de differentes sources disponibles au-dela de leurs divergences. Pour cela, ils doivent aligner, fusionner ou integrer ces ontologies. La decouverte de mappings est un point cle dans la resolution efficace des heterogeneites entre ontologies. Nous developpons une architecture qui connecte des syst…
Adaptive design optimization: a mutual information-based approach to model discrimination in cognitive science.
2010
Discriminating among competing statistical models is a pressing issue for many experimentalists in the field of cognitive science. Resolving this issue begins with designing maximally informative experiments. To this end, the problem to be solved in adaptive design optimization is identifying experimental designs under which one can infer the underlying model in the fewest possible steps. When the models under consideration are nonlinear, as is often the case in cognitive science, this problem can be impossible to solve analytically without simplifying assumptions. However, as we show in this letter, a full solution can be found numerically with the help of a Bayesian computational trick d…