Reflection (mathematics)In mathematics, a reflection (also spelled reflexion) is a mapping from a Euclidean space to itself that is an isometry with a hyperplane as a set of fixed points; this set is called the axis (in dimension 2) or plane (in dimension 3) of reflection. The image of a figure by a reflection is its in the axis or plane of reflection. For example the mirror image of the small Latin letter p for a reflection with respect to a vertical axis (a vertical reflection) would look like q.
Signal reflectionIn telecommunications, signal reflection occurs when a signal is transmitted along a transmission medium, such as a copper cable or an optical fiber. Some of the signal power may be reflected back to its origin rather than being carried all the way along the cable to the far end. This happens because imperfections in the cable cause impedance mismatches and non-linear changes in the cable characteristics. These abrupt changes in characteristics cause some of the transmitted signal to be reflected.
Global workforceGlobal workforce refers to the international labor pool of workers, including those employed by multinational companies and connected through a global system of networking and production, foreign workers, transient migrant workers, remote workers, those in export-oriented employment, contingent workforce or other precarious work. As of 2012, the global labor pool consisted of approximately 3 billion workers, around 200 million unemployed.
Bains publicsvignette|Thermes romains conservés en état à Bath au Royaume-Uni. (Photomontage à partir de photographies prises en 2006.) Les bains publics sont des lieux d'hygiène corporelle accessibles à des personnes ne demeurant pas dans le même bâtiment. Le mot « publics » laisse entendre que ces lieux sont accessibles à tous. Cependant l'accès peut en être limité pour des raisons d'ethnie, de sexe, de religion ou de statut social. Les premiers remonteraient à la civilisation de l'Indus (« grand bain » de Mohenjo-daro).
Spa (établissement)Un spa ou centre d'hydrothérapie est un établissement de soins esthétiques ou de remise en forme à l'aide de l'hydrothérapie. Les méthodes utilisées peuvent comprendre le bain et la douche d'hydromassage, le bain de boue, le bain de vapeur, le sauna, la gymnastique aquatique. Le nom commun spa provient de celui de la ville de Spa en Belgique.
