(objet round) ball. une boule de cristal a crystal ball. roulÃ© en boule curled up in a ball. (pour jouer) bowl. jouer aux boules to play bowls. * se mettre en boule to fly off the handle, to blow one's top. perdre la boule to go off one's rocker *. boule de gomme. nf (=bonbon) gum.
Communications security is the discipline of preventing unauthorized interceptors from accessing telecommunications in an intelligible form, while still delivering content to the intended recipients. In the United States Department of Defense culture, it is often referred to by the abbreviation COMSEC. The field includes cryptographic security, transmission security, emissions security and physical security of COMSEC equipment and associated keying material. COMSEC is used to protect both classified and unclassified traffic on military communications networks, including voice, video, and data.
The matrix materials are usually the same, that is C, SiC, alumina and mullite. Generally, CMC names include a combination of type of fibre/type of matrix. For example, C/C stands for carbon-fibre-reinforced carbon (carbon/carbon), or C/SiC for carbon-fibre-reinforced silicon carbide.