loop carrier system
31SelTrac — is a digital signalling technology used to control the movements of rail vehicles originally developed by Alcatel. SelTrac is now sold by Thales. SelTrac Communications Based Train Control (CBTC) technology SelTrac is a family of three different… …
32Aeroponics — is the process of growing plants in an air or mist environment without the use of soil or an aggregate medium. Aeroponic culture differs from both hydroponics and in vitro (Plant tissue culture) growing. Unlike hydroponics, which uses water as a… …
33building construction — Techniques and industry involved in the assembly and erection of structures. Early humans built primarily for shelter, using simple methods. Building materials came from the land, and fabrication was dictated by the limits of the materials and… …
34GTD-5 EAX — The GTD 5 EAX (General Telephone Digital Number 5 Electronic Automatic Exchange) is the Class 5 telephone switch developed by GTE Automatic Electric Laboratories. This digital central office telephone circuit switching system is used in the… …
35Orion (spacecraft) — Infobox Spacecraft Name = Orion Caption = Orion logo designed by Michael Okuda Organization = NASA Major Contractors = Lockheed Martin Bus = Mission Type = Crew Exploration Vehicle Flyby Of = Satellite Of = Earth, Moon, Asteroid, Mars (possibly)… …
36Operation Strikeback — Part of Cold War (1953–1962) The GIUK Gap . Type NATO …
37Digital subscriber line access multiplexer — A Digital Subscriber Line Access Multiplexer (DSLAM, often pronounced dee slam ) allows telephone lines to make faster connections to the Internet. It is a network device, located in the telephony exchanges of the service providers, that connects …
38Telephone line — For the Electric Light Orchestra song, see Telephone Line (Electric Light Orchestra song). Phone pole with phone and mainly electric lines …
39Phantom circuit — In telecommunication and electrical engineering, a phantom circuit is an electrical circuit derived from suitably arranged wires with one or more conductive paths being a circuit in itself and at the same time acting as one conductor of another… …
40Repeater — This article is about the electronic device. For other uses, see Repeater (disambiguation). A wireless repeater. A repeater is an electronic device that receives a signal and retransmits it at a higher level and/or higher power, or onto the other …
