K-distribution

About: K-distribution is a research topic. Over the lifetime, 1281 publications have been published within this topic receiving 51774 citations.

Moments of nonidentical order statistics from burr xii distribution with gamma and normal outliers

Abstract: There are some distributions with no simple closed form for distribution functions such as the Normal and Gamma distributions. This will be the problem if we want to find moments of nonidentical order statistics in the presence of Gamma and Normal outliers observations. We used the idea of approximating Normal and Gamma distributions with Burr type XII distribution. We get single moments for order statistics from sample of independent nonidentically distributed Burr XII random variables that contains p-outlier from Normal or Gamma distributions. Approximating these distributions with Burr XII distribution and then we compared the results by previous method.

A comparison of the Homodyned K-distribution and the single distributions for RF ultrasonic speckle modeling

Abstract: For observing the parameters and the fitting performance, this paper compares the Homodyned K-distribution with the single distributions for RF ultrasonic speckle modeling. To implement different scatterer distributions representing a variable density of random scatterers with or without coherent component, A set of 3D scatterer models are built based on a three-dimensional Hilbert curve following Gamma distributions with different values of shape and scale parameters. The RF data are simulated by using the Field II software. Then the maximum likelihood estimation (MLE) for statistical histograms of the energy of the RF data is performed to obtain the values of log-likelihood and model parameters. In order to evaluate the fitting performance and parameter meaning of the HK distribution, the mean and standard deviation of these estimated values are compared with those based on the optimal fitting model chosen from commonly used single-distributions (OSD), the K, Rayleigh and Rician distributions. The results show the parameters of Homodyned K-distribution obtained by the MLE could independently represent the clustered, random or uniform characteristics for scatterer distribution. However, the fitting accuracy could only catch up with that based on the OSD joint model under the condition that the tissue contains the scatterers from medium to high effective-density, as well as deterministic or non-deterministic components. The OSD model is still a better choice in the case of the fitting performance emphasized in practice, especially the tissue with a wider range of scatterer densities and deterministic components.

On the distributions of the densities involving non-zero zeros

Abstract: In the present paper, we introduce the probability density functions involving non-zero zeros of the Bessel and Legendre functions. Then, we evaluate the distributions of the characteristic functions defined by these probability density functions and again obtain their related functions and polynomials. Finally, we prove the infinite divisibility of these probability density functions.

Distribution Identification, Analysis and Approximation via Mellin Transforms

Abstract: SYNOPTIC ABSTRACTThis paper exploits use of Mellin transforms in the study of product and quotient distributions by (a) identification of distributions (b) derivation of distributions (c) moment analysis of distributions (d) use of approximating functions (e) examples.