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Comment on ``Force Balance at the Transition from Selective Withdrawal to Viscous Entrainment
Comment on paper by Blanchette and Zhang, Phys. Rev. Lett. 102, 144501
(2009)
Adaptive minimum symbol error rate beamforming assisted receiver for quadrature amplitude modulation systems
An adaptive beamforming assisted receiver is proposed for multiple antenna aided multiuser systems that employ bandwidth efficient quadrature amplitude modulation (QAM). A novel minimum symbol error rate (MSER) design is proposed for the beamforming assisted receiver, where the system’s symbol error rate is directly optimized. Hence the MSER approach provides a significant symbol error ratio performance enhancement over the classic minimum mean square error design. A sample-by-sample adaptive algorithm, referred to as the least symbol error rate (LBER) technique, is derived for allowing the adaptive implementation of the system to arrive from its initial beamforming weight solution to MSER beamforming solution
Fixed-domain asymptotic properties of tapered maximum likelihood estimators
When the spatial sample size is extremely large, which occurs in many
environmental and ecological studies, operations on the large covariance matrix
are a numerical challenge. Covariance tapering is a technique to alleviate the
numerical challenges. Under the assumption that data are collected along a line
in a bounded region, we investigate how the tapering affects the asymptotic
efficiency of the maximum likelihood estimator (MLE) for the microergodic
parameter in the Mat\'ern covariance function by establishing the fixed-domain
asymptotic distribution of the exact MLE and that of the tapered MLE. Our
results imply that, under some conditions on the taper, the tapered MLE is
asymptotically as efficient as the true MLE for the microergodic parameter in
the Mat\'ern model.Comment: Published in at http://dx.doi.org/10.1214/08-AOS676 the Annals of
Statistics (http://www.imstat.org/aos/) by the Institute of Mathematical
Statistics (http://www.imstat.org
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