Transport
or transportation is the movement of people, animals and goods from one
location to another. Modes of transport include air, rail, road, water,cable,pipeline and space. The field can be divided into infrastructure,
vehicles and operations. Transport is important because it enables trade
between persons, which is essential for the development of civilizations.
Transport
infrastructure consists of the fixed installations including roads, railways,
airways, waterways, canals and pipelines and terminals such as airports,railway
stations, bus stations, warehouses, trucking terminals, refueling depots
(including fueling docks and fuel stations) and seaports. Terminals may be used
both for interchange of passengers and cargo and for maintenance.
Vehicles
traveling on these networks may include automobiles, bicycles, buses, trains,
trucks, people, helicopters, watercraft, spacecraft and aircraft. Operations
deal with the way the vehicles are operated, and the procedures set for this
purpose including financing, legalities and policies. In the transport
industry, operations and ownership of infrastructure can be either public or
private, depending on the country and mode.
Passenger
transport may be public, where operators provide scheduled services, or
private. Freight transport has become focused on containerization, althoughbulk
transport is used for large volumes of durable items. Transport plays an
important part in economic growth and globalization, but most types cause air
pollution and use large amounts of land. While it is heavily subsidized by
governments, good planning of transport is essential to make traffic flow and
restrainurban sprawl.
Mode
A
mode of transport is a solution that makes use of a particular type of vehicle,
infrastructure and operation. The transport of a person or of cargo may involve
one mode or several of the modes, with the latter case being called intermodal
or multimodal transport. Each mode has its own advantages and disadvantages,
and will be chosen for a trip on the basis of cost, capability, and route.
Human-powered
Human-powered
transportremains common in developing countries.
Human
powered transport, a form of sustainable transportation, is the transport of
people and/or goods using human muscle-power, in the form of walking, running
andswimming. Modern technology has allowed machines to enhance human power.
Human-powered transport remains popular for reasons of cost-saving, leisure,physical exercise, and environmentalism; it is sometimes the only type
available, especially in underdeveloped or inaccessible regions.
Although
humans are able to walk without infrastructure, the transport can be enhanced
through the use of roads, especially when using the human power with vehicles,
such as bicycles and inline skates. Human-powered vehicles have also been
developed for difficult environments, such as snow and water, by watercraft
rowing andskiing; even the air can be entered with human-powered aircraft.
Animal-powered
Animal-powered
transport is the use of working animals for the movement of people and
commodities. Humans may ride some of the animals directly, use them as pack
animals for carrying goods, or harness them, alone or in teams, to pull sleds
or wheeled vehicles.
Air
An
Air France Airbus A318 lands at London Heathrow Airport.
A
fixed-wing aircraft, commonly called airplane, is a heavier-than-air craft
where movement of the air in relation to the wings is used to generate lift.
The term is used to distinguish this from rotary-wing aircraft, where the
movement of the lift surfaces relative to the air generates lift. A gyroplane
is both fixed-wing and rotary-wing. Fixed-wing aircraft range from small
trainers and recreational aircraft to large airliners and military cargo
aircraft.
Two
things necessary for aircraft are air flow over the wings for lift and an area
for landing. The majority of aircraft also need an airport with the
infrastructure to receive maintenance, restocking, refueling and for the
loading and unloading of crew, cargo and passengers. While the vast majority of
aircraft land and take off on land, some are capable of take off and landing on
ice, snow and calm water.
The
aircraft is the second fastest method of transport, after the rocket.
Commercial jets can reach up to 955 kilometres per hour (593 mph), single-engine
aircraft 555 kilometres per hour (345 mph). Aviation is able to quickly
transport people and limited amounts of cargo over longer distances, but incur
high costs and energy use; for short distances or in inaccessible places
helicopters can be used.[1] As of April 28, 2009 The Guardian article notes
that, "the WHO estimates that up to 500,000 people are on planes at any
time.
Rail
The
New York City Subway is the world's largest rapid transit system by length of
routes and by number ofstations.
Rail
transport is where a train runs along a set of two parallel steel rails, known
as a railway or railroad. The rails are anchored perpendicular to ties (or
sleepers) of timber, concrete or steel, to maintain a consistent distance
apart, or gauge. The rails and perpendicular beams are placed on a foundation
made of concrete, or compressed earth and gravel in a bed of ballast.
Alternative methods include monorail and maglev.
A
train consists of one or more connected vehicles that operate on the rails.
Propulsion is commonly provided by a locomotive, that hauls a series of
unpowered cars, that can carry passengers or freight. The locomotive can be
powered by steam, diesel or by electricity supplied by trackside systems.
Alternatively, some or all the cars can be powered, known as a multiple unit.
Also, a train can be powered by horses, cables, gravity, pneumatics and gas
turbines. Railed vehicles move with much less friction than rubber tires on
paved roads, making trains more energy efficient, though not as efficient as
ships.
Intercity
trains are long-haul services connecting cities;[3] modern high-speed rail is
capable of speeds up to 350 km/h (220 mph), but this requires specially built
track. Regional and commuter trains feed cities from suburbs and surrounding
areas, while intra-urban transport is performed by high-capacity tramways and rapid
transits, often making up the backbone of a city's public transport. Freight
trains traditionally used box cars, requiring manual loading and unloading of
the cargo. Since the 1960s, container trains have become the dominant solution
for general freight, while large quantities of bulk are transported by
dedicated trains.
Road
The
Harbor Freeway is often heavily congested at rush hour in Downtown Los Angeles.
A
road is an identifiable route, way or path between two or more places. Roads
are typically smoothed, paved, or otherwise prepared to allow easy travel;though
they need not be, and historically many roads were simply recognizable routes
without any formal construction or maintenance. In urban areas, roads may pass
through a city or village and be named as streets, serving a dual function as
urban space easement and route
The
most common road vehicle is the automobile; a wheeled passenger vehicle that
carries its own motor. Other users of roads include buses, trucks,motorcycles,bicycles and pedestrians. As of 2010, there were 1.015 billion automobiles
worldwide. Road transport offers a complete freedom to road users to transfer
the vehicle from one lane to the other and from one road to another according
to the need and convenience. This flexibility of changes in location,
direction, speed, and timings of travel is not available to other modes of
transport. It is possible to provide door to door service only by road
transport.
Automobiles
provide high flexibility with low capacity, but require high energy and area
use, and are the main source of noise and air pollution in cities; buses allow
for more efficient travel at the cost of reduced flexibility.[8] Road transport
by truck is often the initial and final stage of freight transport.
Water
Built
by the Dutch to transport spices, now used by the local fishermen to get to the
sea, Negombo Dutch canal, Sri Lanka
Automobile
ferry in Croatia
Water
transport is movement by means of a watercraft—such as a barge, boat, ship or
sailboat—over a body of water, such as a sea, ocean, lake, canal or river. The
need for buoyancy is common to watercraft, making the hull a dominant aspect of
its construction, maintenance and appearance.
In
the 19th century the first steam ships were developed, using a steam engine to
drive a paddle wheel or propeller to move the ship. The steam was produced in a
boiler using wood or coal and fed through a steam external combustion engine.
Now most ships have an internal combustion engine using a slightly refined type
of petroleum called bunker fuel. Some ships, such as submarines, use nuclear
power to produce the steam. Recreational or educational craft still use wind
power, while some smaller craft use internal combustion engines to drive one or
more propellers, or in the case of jet boats, an inboard water jet. In shallow
draft areas, hovercraft are propelled by large pusher-prop fans.
Although
slow, modern sea transport is a highly efficient method of transporting large
quantities of goods. Commercial vessels, nearly 35,000 in number, carried 7.4
billion tons of cargo in 2007.Transport by water is significantly less costly
than air transport for transcontinental shipping; short sea shipping and
ferries remain viable in coastal areas.
Other modes
Trans-Alaska
Pipeline for crude oil
Pipeline
transport sends goods through a pipe; most commonly liquid and gases are sent,
but pneumatic tubes can also send solid capsules using compressed air. For
liquids/gases, any chemically stable liquid or gas can be sent through a
pipeline. Short-distance systems exist for sewage, slurry, water and beer,
while long-distance networks are used for petroleum and natural gas.
Cable
transport is a broad mode where vehicles are pulled by cables instead of an
internal power source. It is most commonly used at steep gradient. Typical
solutions include aerial tramway, elevators, escalator and ski lifts; some of
these are also categorized as conveyor transport.
Spaceflight
is transport out of Earth's atmosphere into outer space by means of a
spacecraft. While large amounts of research have gone into technology, it is
rarely used except to put satellites into orbit, and conduct scientific
experiments. However, man has landed on the moon, and probes have been sent to
all the planets of the Solar System.
Suborbital
spaceflight is the fastest of the existing and planned transport systems from a
place on Earth to a distant other place on Earth. Faster transport could be
achieved through part of a low Earth orbit, or following that trajectory even
faster using the propulsion of the rocket to steer it.
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