General Science

  • noun a device at the centre of a Token-Ring network which provides a logical star topology in which nodes are connected to the concentrator. Inside the device is a physical ring circuit that connects all the nodes together.


  • noun a node which provides access for one or more stations to the network
  • noun the device at the centre of a star topology 10Base-T Ethernet network that receives signals from one port and regenerates them before sending them out to the other ports
  • noun a device in which all the cables from nodes are interconnected


  • A device, such as a multiplexer, which combines multiple communications channels or signals.
  • A device which provides a communications path that links many lower-speed channels to one or more higher-speed channels. A benefit of this arrangement is that it accommodates multiple-user connectivity with a reduced amount of circuit use.
  • A device which utilizes optical elements to increase the amount of light, especially sunlight, incident upon a photovoltaic cell or panel.