encyclopedia

ABANDONMENT

In public transportation operations, a procedure whereby a carrier ceases operations on all or part of its lines and routes on permission from the appropriate regulatory authorities. 2. In “rights-of-way,” the relinquishment of the public interest in right-of-way or activity…

ABEND

An abnormal end to a computer job. An abend (a combining of two words, abnormal end, when operator messages were as short as possible) is an abnormal, rather than planned, end or termination of a computer program because of some…

ABOVE GROUND STATION

A station in which the tracks and platform are either located on an aerial structure or rest directly on grade.

ABSOLUTE PERMISSIVE BLOCK

A block within which the movement of trains on a desigated section of track or tracks is directed by signals automatically controlled and without train-order authority and without superiority of trains.

ABSTRACT CHOICE MODEL

A model based on the assumption that it is not necessary to identify travel choice variables by the name of their mode, destination, time of day, or other characteristic; instead, they are identified by their attributes, for example, variables describing…