Physical Medium: Physical Medium refers to the actual physical interfaces Several interfaces are defined including STS-1, STS-3c, STS-12c, STM-1, STM-4, DS1, E1, DS2, E3, DS3, E4, FDDI-based, Fiber Channel-based, and STP These range in speeds from 1 544Mbps through 622 08 Mbps
Preventive Maintenance is a series of tasks that either extend the life of an asset, or that detect that an asset has had critical wear and is going to fail or break down
Passing Mode A method used in Line-Transect surveys in which a sighting vessel does not approach the sighted whales, i e , the vessel continues to cruise on the trackline Experiments showed that the estimated school size (the number of whales in a sighted school) given by the PM is about 30% smaller than the true value Both the CM and the PM are now used in combination in the IWC sighting survey programs
(Post Mile) is the mileage measured in statute miles from a county line or the beginning of a route to another county line or the ending of the route Each post mile along a route in a county is a unique location on the State Highway System