It is necessary to identify speckled regions in ultrasound images to control adaptive speckle suppression algorithms, for tissue characterisation, and to estimate the elevational separation of B-scans by speckle decorrelation. Previous authors have proposed classification techniques based on second order powers of the homodyned k-distribution, or lower order powers of the more limited k-distrib...

This report presents the results of a study, the main aim of which was proper prediction of sea clutter characteristics and modelling of sea clutter including both the temporal and spatial properties of the return signals. More detail has been given to the K-distribution as this model enables the simulation of clutter with a good level of approximation to the real data. APPROVED FOR PUBLIC RELE...

Accurate and efficient modeling of shock-layer radiative heat loads is critical for many spacecraft designs. A correlated-k distribution method has been developed for the most important atomic species (N and O), which provides great accuracy with high numerical efficiency for the evaluation of radiative transfer in a hot plasma. Challenges posed by typical nonequilibrium gas conditions and extr...

Given n independent random marked d-vectors Xi with a common density, define the measure νn = ∑ i ξi, where ξi is a measure (not necessarily a point measure) determined by the (suitably rescaled) set of points near Xi. Technically, this means here that ξi stabilizes with a suitable power-law decay of the tail of the radius of stabilization. For bounded test functions f on R, we give a central l...

In this contribution, an accurate description of the ocean backscatter from a probability density function is proposed. The Elfouhaily spectrum has been used to generate a realistic sea surface. The scattering field will be computed by using the Physical Optics (PO). The K distribution has been already used to characterize the Radar Cross Section (RCS) of the sea surface. However, the probabili...

Resonance trapping appears in open many-particle quantum systems at high level density when the coupling to the continuum of decay channels reaches a critical strength. Here a reorganization of the system takes place and a separation of different time scales appears. We investigate it under the influence of additional weakly coupled channels as well as by taking into account the real part of th...

The Cramer-Rao Lower Bound is widely used in statistical signal processing as a benchmark to evaluate unbiased estimators. However, for some random variables, the probability density function has no closed analytical form. Therefore, it is very hard or impossible to evaluate the Cramer-Rao Lower Bound directly. In these cases the characteristic function may still have a closed and even simple f...

ABSTRACT- Different soil potassium (K) pools including soluble, exchangeable and non-exchangeable in surface and subsurface soils may be totally used by canola roots at different growth stages under drought conditions. A field experiment was conducted for one growing season (2013-2014) to study K pools changes during growth stages of two rapeseed cultivars under drought. The experiment was arra...

We say that a distribution over {0, 1} is ( , k)-wise independent if its restriction to every k coordinates results in a distribution that is -close to the uniform distribution. A natural question regarding ( , k)-wise independent distributions is how close they are to some k-wise independent distribution. We show that there exists ( , k)-wise independent distribution whose statistical distance...

many commonly used statistical methods require that the population distribution be nearly normal. unfortunately, in some papers the one-sample kolmogorov-smirnov test has been used for testing normality while the assumptions of applying this test are not satisfied. to conduct this test, it is assumed that the population distribution is fully specified. in practical situation where the mean and ...