two-level switch
31Elevator — For other uses, see Elevator (disambiguation). A set of lifts in the lower level of a London Underground station. The arrows indicate each elevator s position and direction of travel …
32Life Sciences — ▪ 2009 Introduction Zoology In 2008 several zoological studies provided new insights into how species life history traits (such as the timing of reproduction or the length of life of adult individuals) are derived in part as responses to… …
33Telephone exchange — A telephone operator manually connecting calls with cord pairs at a telephone switchboard. In the field of telecommunications, a telephone exchange or telephone switch is a system of electronic components that connects telephone calls. A central… …
34Thread (computer science) — This article is about the concurrency concept. For the multithreading in hardware, see Multithreading (computer architecture). For the form of code consisting entirely of subroutine calls, see Threaded code. For other uses, see Thread… …
35Glossary of contract bridge terms — These terms are used in Contract bridge[1][2] , or the earlier game Auction bridge, using duplicate or rubber scoring. Some of them are also used in Whist, Bid whist, and other trick taking games. This glossary supplements the Glossary of card… …
36Cricket — A bowler bowling to a batsman. The paler strip is the cricket pitch. The two sets of three wooden stumps on the pitch are the wickets. The two …
37Overhead lines — This article is about the transmission of electrical power to road and rail vehicles. For transmission of bulk electrical power to general consumers, see Electric power transmission. For powerlines mounted on pylons, see overhead power line.… …
38Train station — Rail transport Operations Track Maintenance High speed Gauge Stations …
39Number Five Crossbar Switching System — The Number Five Crossbar Switching System or 5XB switch, designed by Bell Labs and made by Western Electric, was in use in Bell System telephone exchanges from 1948 to the 1980s. Its principal use was as a Class 5 telephone switch, though… …
40Memory management unit — This 68451 MMU could be used with the Motorola 68010 A memory management unit (MMU), sometimes called paged memory management unit (PMMU), is a computer hardware component responsible for handling accesses to memory requested by the CPU. Its… …
