optical signature
61Liquid crystal — Schlieren texture of liquid crystal nematic phase Liquid crystals (LCs) are a state of matter that have properties between those of a conventional liquid and those of a solid crystal.[1] For instance, an LC may flow like a liquid, but its… …
62Second — This article is about the unit of time. For other uses, see Second (disambiguation). A light flashing approximately once per second. The second (SI unit symbol: s; informal abbreviation: sec) is a unit of measurement of time, and is the… …
63Identity document — National identity card redirects here. For cards referred to in the English language as national identity card , see National identity card (disambiguation). An identity document (also called a piece of identification or ID, or colloquially as… …
64Headlamp — Headlight redirects here. For other uses, see Headlight (disambiguation). High Beams redirects here. For the urban legend also known by that name, see Killer in the backseat. A motor scooter s front with an impractical number and variety of… …
65Ship gun fire-control system — Mk 37 Director c1944 with Mk 12 (rectangular antenna) and Mk 22 orange peel Ship gun fire control systems (GFCS) enable remote and automatic targeting of guns against ships, aircraft, and shore targets, with or without the aid of radar or optical …
66Gamma ray burst — [ GRB 990123 taken on January 23, 1999. The burst is seen as a bright dot denoted by a square on the left, with an enlarged cutout on the right. The object above it with the finger like filaments is the originating galaxy. This galaxy seems to be …
67Sign convention — In physics, a sign convention is a choice of the physical significance of signs (plus or minus) for a set of quantities, in a case where the choice of sign is arbitrary. Arbitrary here means that the same physical system can be correctly… …
68Quantum dot — Part of a series of articles on Nanomaterials Fullerenes …
69Glossary of military abbreviations — List of terms, acronyms, information, related to modern armour, artillery, infantry, weapons, and related military subject matter.* AA anti aircraft * AAA anti aircraft artillery Triple A * AAAV Advanced Amphibious Assault Vehicle * AAD Armoured… …
70motion picture, history of the — Introduction history of the medium from the 19th century to the present. Early years, 1830–1910 Origins The illusion of motion pictures is based on the optical phenomena known as persistence of vision and the phi phenomenon. The first …
