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The spatial Bessel filters are analyzed for their ability to reduce ultrasonic speckle and increase the boundaries of regions of interest (ROI) in medical B-mode images and a new parameter is defined for measuring the edge visibility. The results have shown the use of Bessel spatial filters in providing speckle reduction along with the ability to increase the boundaries of regions of interest in B-mode images and the quantitative measures have supported the visual perception of contrast and enhanced edge visibility.

A multiparameter approach involving classification of breast masses in ultrasonic B-scan images is described and discussed.

The envelope of the backscattered echo from tissue is described by means of a compound probability density function (pdf).

Breast cancer diagnosis through ultrasound tissue characterization was studied using receiver operating characteristic (ROC) analysis of combinations of acoustic features, patient age, and radiological findings. A feature fusion method was devised that operates even if only partial diagnostic data are available. The ROC methodology uses ordinal dominance theory and bootstrap resampling to evaluate [A.sub.z] and confidence intervals in simple as well as paired data analyses. The combined diagnostic feature had an [A.sub.z] of 0.96 with a confidence interval of [0.93, 0.99] at a significance level of 0.05. The combined features show statistically significant improvement over prebiopsy radiological findings. These results indicate that ultrasound tissue characterization, in combination with patient record and clinical findings, may greatly reduce the need to perform biopsies of benign breast lesions. Index Terms--Bootstrap, breast ultrasonic imaging, ROC analysis, tissue characterization.

An approach to demonstrate flat fading in communication systems is presented here, wherein the basic concepts are reinforced by means of a series of MATLAB (Mathworks, Inc., Natick, MA 01760-2098 USA) simulations. Following a brief introduction to fading in general, models for flat fading are developed and simulated using MATLAB. The concept of outage is also demonstrated using MATLAB. The authors suggest that the use of MATLAB exercises will assist the students in gaining a better understanding of the various nuances of flat fading. Index Terms--Fading, MATLAB-based instruction, mobile communications, simulation of fading, wireless systems.

Chi‐square goodness of fit testing to examine whether or not it is reasonable to assume that a random sample of the data comes from a specific probability density was one of the topics covered in an undergraduate engineering probability course. In the absence of details on this topic in engineering probability books, a Matlab® demo was created to facilitate the link between theory and practice. The step‐by‐step procedure to determine the closest fit among a number of continuous densities has been demonstrated involving binning (fixed width and fixed population), parameter estimation, and computation of the test statistic, degrees of freedom and the P values. The cautionary aspects of the test regarding the variability in test results have been illustrated by choosing a smaller size data through permutation. The pedagogical aspects of procedure demonstrated suggest that it may be used to fill the gaps in textbooks devoted to probability and statistics. [ABSTRACT FROM AUTHOR]