The paper describes the concept of data security in a mobile environment. The objective is to develop Java software applications, MIDlets for mobile devices, which implement data protection at different levels. Existing and proposed solutions are described by defining security models and architectures. From the software development point of view, the paper describes two API’s, JSR 177 [1] and B...

“So, the whole reason the French people can’t really dance, is because they haven’t got the beat in their blood. And why don’t they live and feel the beat? It’s because their language has no tonic accent [. . . ] This is something about the energy you can find in music. I mean specifically African music. As I understand, it’s dynamic and bouncy because it’s driven by the beat. And it’s syncopat...

Elliptic Curve Cryptography (ECC) is based on cyclic groups, where group elements are represented as points in a finite plane. All ECC cryptosystems implicitly assume that only valid group elements will be processed by the different cryptographic algorithms. It is well-known that a check for group membership of given points in the plane should be performed before processing. However, in several...

The virus diffusion in a ventilated room with the droplets produced by coughing and breathing are presented Lagrangian model. When human body is located middle of two locations AC, front behind body, three angles Air Conditioning (AC) gate applied 0°, 30°, 60° to show droplet particle these cases. Three types velocity profiles were selected, real coughing, sinusoidal cough, cough jet one profil...