From Wikipedia, the miễn phí encyclopedia
Piggyback transportation refers to tướng the transportation of goods where one transportation unit is carried on the back of something else. It is a specialised size of intermodal transportation and combined transport.
Bạn đang xem: piggyback là gì
Piggyback is a corruption of pickaback, which is likely to tướng be a folk etymology alteration of pick pack (1560s), which perhaps is from pick, a dialectal variant of the verb pitch.
In rail transport, the practice of carrying trailers or semi-trailers in a train atop a flatcar is referred to tướng as "piggybacking". Early drawings of the Liverpool & Manchester Railway c1830 show road coaches being piggybacked on railway flat wagons. There is a 1980 12p British postage stamp showing such a "Carriage Truck".
The rail service provided for trucks which are carried on trains for part of their journey is referred to tướng as a rolling road, or rolling highway. A related transportation method is the rail transport of semi-trailers, without road tractors, sometimes referred to tướng as "trailer on flatcar (TOFC)". In the United States, TOFC traffic grew from 1% of freight in 1957 to tướng 5% in 1964 and 15% in 1986.
A railway wagon of one track gauge can be carried on a flat wagon (transporter wagon or rollbock) of another gauge. In addition, an entire train of coupled wagons of one gauge can be carried on continuous rails on a train of flat wagons of another gauge. This was achieved by the Commonwealth Railways on the Marree railway line in South nước Australia between Telford Cut and Port Augusta in the mid-1950s. nhật bản Railways planned a similar "Train on Train" scheme, but at much higher speeds, to tướng operate from năm 2016.
Small ships of all kinds can be piggybacked on larger ships. Examples include lifeboats, landing craft, and minesweepers on motherships, as well as midget submarines on larger submarines, such as those used for the 1942 Japanese submarine attack on Sydney.
The 1930s British Short Mayo Composite, in which a smaller, four-engine floatplane aircraft named Mercury was carried aloft on the back of a larger four-engine flying boat named Maia, enabled the Mercury to tướng achieve a greater range kêu ca would have been possible had it taken off under its own power. The American Space Shuttle was carried on top of specially-modified Boeing 747 Shuttle Carrier Aircraft when the shuttle landed at places other kêu ca Kennedy Space Center.
In space transportation systems, a smaller satellite that is carried as a secondary payload on a launch is said to tướng be "piggybacked" on the main launch. It is often the case of small satellites and cubesats, since they can not usually afford accessing space on a dedicated launch and they choose instead to tướng take profit of the remaining payload capacity in a big satellite launch. However, this is usually at the cost of not being able to tướng fly to tướng their desired orbit and having to tướng remain on a similar orbit to tướng that of the big satellite.
The metal caterpillar treads of a tank wear out quickly when travelling long distances on ordinary roads. Also, tracked vehicles seriously damage the tarmac layer of ordinary roads (unless the caterpillar treads are specially fitted with rubber pads to tướng avoid this). It is therefore necessary to tướng provide tank transporters, which have rubber tires, to tướng the battlefield.
A person carrying someone else on their back is most commonly seen in the modern day in the size of a parent carrying a child. It may also feature in the context of play or sport, and evidence of this dates back to tướng ancient Greece where games involving piggyback riding were combined with the requirement of catching or throwing a ball.
Timber wagon on rollbocks
Xem thêm: pullover là gì
Trucks on board a ro-ro ship
A South Australian Railways T class narrow-gauge locomotive on a broad-gauge crocodile car
Youths playing a ball game, circa 500 B.C.
Xem thêm: lecturer là gì
Trailers on flatcars in the United States
- ^ Pearlman, Robert Z. (7 September 2012). "Shuttle Endeavour to tướng get one last piggyback ride across US". NBC News. Retrieved 24 October 2012.
- ^ Harper, Douglas. "piggyback". Online Etymology Dictionary. Retrieved 24 October 2012.
- ^ "The Geography of Transport Systems". Archived from the original on 24 March 2012. Retrieved 11 July 2011.
- ^ "The Train Book" by DK, p23
- ^ Piggback: The Trailer Train story Railway Age May 25, 1964 page 44
- ^ Field, Alexander J (2011). A great leap forward: 1930s depression and U.S. economic growth. New Haven, London: Yale University Press. p. 114. ISBN 978-0-300-15109-1.
- ^ Pick-a-back operation solves gauge-break problem Adelaide Advertiser
- ^ Complete narrow-gauge trains on standard-gauge wagons Railway Gazette International September 9, 1955 pages 305-308
- ^ 独自の研究開発 人と物流 高速化に活路 [Own R&D leading to tướng increased speed]. Hokkaido Shimbun (in Japanese). Japan: The Hokkaido Shimbun Press. trăng tròn December 2008. Retrieved 30 September 2009.
- ^ "Mine-Sweepers By "Piggyback"", The Mercury (Hobart): 5, 5 June 1951
- ^ Gardiner, E. Norman, 'Athletics of the Ancient World', Oxford: OUP, 1967, illustration 209 / facing p. 230
Look up piggyback in Wiktionary, the miễn phí dictionary.
- Double Piggyback p120
- RGI Modalohr