To protect mobile phone from tracking by third parties, mobile telephony systems rely on periodically changing pseudonyms. We experimentally and formally analyse the mechanism adopted to update these pseudonyms and point out design and implementation weaknesses that defeat its purpose by allowing the identification and/or tracking of mobile telephony users. In particular, the experiments show t...

Photonic crystal design procedure for negative refraction has so far been based on trial and error. In this paper, for the first time, a novel and systematic design procedure based on physical and mathematical properties of photonic crystals is proposed to design crystal equi-frequency contours (EFCs) to produce negative refraction. The EFC design is performed by the help of rectangular stair-c...

Tesla turbine rotor, a special case of the flow between two corotating disks, has been studied in past analytically and performance is discussed both qualitatively quantitatively. However, there no systematic design criteria/process given to rotor expander peer-reviewed literature. Such procedure, presented this article, allows researchers engineers optimise for fluid condition (Power, rotation...