Typically, coke-oven gas is obtained from a battery comprising a number of narrow, vertical chambers, or ovens (0.5m wide, 5m high and 12m long) built of silica brick that are separated by heating ducts, such that heat is transmitted to the coal through both sides of the chamber walls.
ISO keyboard symbol for âControlâ. In computing, a Control key is a modifier key which, when pressed in conjunction with another key, performs a special operation (for example, +); similar to the Shift key, the Control key rarely performs any function when pressed by itself.
Just as the keys held on an ordinary real-world key chain or fob control access to the owner's home or car, the mechanisms in the key fob control access to network services and information. The key fob (and similar devices, such as smart cards) provide two-factor authentication.