Digital Search Trees (DST) are one of the most popular data structures storing keys, usually represented by strings. The profile of a digital search tree is a parameter that counts the number of nodes at the same distance from the root. It is a function of the number of nodes and the distance from the root. Several, if not all, tree parameters such as height, size, depth, shortest path, and fil...

In this note we give sufficient conditions for the convergence of the iterative algorithm called weighted-average consensus in directed graphs. We study the discrete-time form of this algorithm. We use standard techniques from matrix theory to prove the main result. As a particular case one can obtain well-known results for non-weighted average consensus. We also give a corollary for undirected...

A psychophysical experiment was carried out to examine the relationship between image contrast and overall perceived brightness. A second phase of the experiment looked at the relationship between the perceived brightness of variegated backgrounds and the simultaneous contrast effect produced by such backgrounds. These results have important ramifications for procedures used to calculate adapti...