encyclopedia

DUAL CONTROL SWITCH

Track switch controlled remotely or operated manually.

DUAL MODE BUS

1. A bus designed to operate both on city streets and on rails or other types of guideways; also known as a Dual-control Bus. 2. Sometimes used to refer to a trolleybus with a diesel or gasoline engine that operates…

DUAL-MODE TRANSIT SYSTEM

A broad category of systems wherein vehicles may be operated in both of two different types of operation or propulsion, for example, manually steered and guided, on highways and on guideways, or with diesel and electric traction. (TRB)

DUAL-MODE VEHICLE

A vehicle that operates both manually on public streets and automatically on an automated guideway. (TRB)

DUAL-POWERED LOCOMOTIVE

A locomotive that is capable of both diesel and electric operation. (TRB)

DUAL-POWERED TURBOELECTRIC

A commuter railroad car capable of either running on electric power from a third rail or overhead wire or self-propulsion by a generator driver by a gas turbine. (TRB)

DUMB TERMINAL

A display terminal without processing capability. Dumb terminals are dependent upon the main computer for processing. All entered data is accepted without further editing or validation.