in the last two decades, the trend in healthcare information technology has been towards digital and multimedia concepts. the next generation of healthcare information systems will consist of a vast network of heterogeneous, autonomous and distributed imaging scanners, hospital information systems (his), medical information from clinical departments such as radiology information systems (ris), ...

This article is a brief exposure of the process approach to a newly emerging area called "discrete event systems" in control theory and summarizes some of the recent developments in this area. Discrete event systems is an area of research that is developing within the interstices of computer, control and communication sciences. The basic direction of research addresses issues in the analysis an...

We investigate the use of ClawZ, a suite of tools for the verification of implementations of control laws, to construct formal models for control systems in the area of communications and signal-processing intensive applications. Whereas ClawZ has been successfully applied to verify control components in avionic systems, special requirements need to be identified and addressed to extend its use...

We present an overview of the field of anonymous communications, from its establishment in 1981 by David Chaum to today. Key systems are presented categorized according to their underlying principles: semitrusted relays, mix systems, remailers, robust & verifiable mixes, and onion routing systems. We include extended discussions of the threat models and usage models that different schemes provi...

The requirement for increased exibility in order to support the many di erent services in wireless communication has motivated the search for new, improved convolutional codes with a large number of di erent code rates. A new design criterion is introduced which results in codes with better performance on both AWGN channels and Rayleigh fading channels. These codes, called Optimum Distance Spec...

A fundamental challenge for present and future communication systems is the ability to transport multimedia content to a wide variety of terminals (TV, PC, PDA, cell phone), over a variety of networks (broadcast, Internet, GPRS, CDMA), at different channel conditions (congestion, high bit-error), different bitrates and different quality-of-service. This challenge leads to a number of technical ...