2,563 research outputs found
Estimating the polarization degree of polarimetric images in coherent illumination using maximum likelihood methods
This paper addresses the problem of estimating the polarization degree of polarimetric images in coherent illumination. It has been recently shown that the degree of polarization associated to polarimetric images can be estimated by the method of moments applied to two or four images assuming fully developed speckle. This paper shows that the estimation can also be conducted by using maximum likelihood methods. The maximum likelihood estimators of the
polarization degree are derived from the joint distribution of the image intensities. We show that the joint distribution of polarimetric images is a multivariate gamma distribution whose marginals are univariate, bivariate or trivariate gamma distributions. This property is used to derive maximum likelihood estimators of the polarization degree using two, three or four images. The proposed
estimators provide better performance that the estimators of
moments. These results are illustrated by estimations conducted on synthetic and real images
Why Can\u27t We Be Friends?: Why California Needs A Lifestyle Discrimination Statute to Protect Employees From Employment Actions Based on Their Off-Duty Behavior
This note explores the employment implications that social networking has on private employees and discusses the need for a lifestyle discrimination statute in California. The note begins with an overview of the increasing use of social networking, both within the employment context as well as within society as a whole. The note then analyzes current privacy protections under federal and California law and contrasts those protections with lifestyle discrimination statutes adopted in Colorado and New York. Ultimately, the note concludes that California should adopt a statute that would provide protection to employees who are terminated for off-duty, off-site behaviors which do not impact a legitimate business interest
Electromagnetic wave propagation and absorption in magnetised plasmas: variational formulations and domain decomposition
We consider a model for the propagation and absorption of electromagnetic
waves (in the time-harmonic regime) in a magnetised plasma. We present a
rigorous derivation of the model and several boundary conditions modelling wave
injection into the plasma. Then we propose several variational formulations,
mixed and non-mixed, and prove their well-posedness thanks to a theorem by
S\'ebelin et~al. Finally, we propose a non-overlapping domain decomposition
framework, show its well-posedness and equivalence with the one-domain
formulation. These results appear strongly linked to the spectral properties of
the plasma dielectric tensor
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