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Automatic Identification System (AIS). Transponders on shipping vessels that rely
on radio signals to broadcast attributes such as position, ship number, heading, and
speed.
Average Vehicle Occupancy (AVO). The number of people traveling by p rivate
passenger vehicles divided by the number of vehicles used.
Average Vehicle Ridership (AVR). The ratio of all people traveling by any mode,
including cars, buses, trains and bicycles (or telecommuting),
in a given area
during a given time period to the number of cars on the road. A key measure of the
efficiency and effectiveness of a transportation network – the higher the AVR, the
lower the level of energy consumption and air pollution.
Double Stack. The movement of containers on articulated rail cars which enables
one container to be stacked on another for better ride quality and railcar utilization.
Downtime. A period during which a vehicle or a whole system is inoperative
because of repairs or maintenance.
Drayage. The movement of a container or trailer to or from the railroad intermodal
terminal to or from the customer’s facility for loading or unloading.
Dry bulk cargo. Cargo which may be loose, granular, free-flowing or solid, such
as grain, coal, and ore, and is shipped in bulk rather than in package form. Dry
bulk cargo is usually handled by specialized mechanical handling equipment at
specially designed dry bulk terminals.
Duopoly. A market that is dominated by two firms provides goods or services.
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