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• 1 Aspects of transport
• 2 Modes and categories
o 2.1 Air transport
o 2.2 Rail
o 2.3 Road transport
2.3.1 Automobile
2.3.2 See also
o 2.4 Water transport
2.4.1 Watercraft
2.4.2 Ship transport
2.4.2.1 See also
• 3 Transport and communications
• 4 Transport and land use
• 5 Transport in cities
o 5.1 See also
• 6 Transport, energy, and the environment
• 7 Research
•
Transport or transportation is the movement of people and goods from one place to another. The term is derived from the Latin trans ("across") and portare ("to carry"). Industries which have the business of providing equipment, actual transport, or goods and services used in transport of goods or people make up a large broad and important sector of most national economies, and are collectively refered to as transport industries.
Aspects of transport
The field of transport has several aspects: loosely they can be divided into a triad of infrastructure, vehicles, and operations. Infrastructure includes the transport networks (roads, railways, airways, waterways, canals, pipelines, etc.) that are used, as well as the nodes or terminals (such as airports, railway stations, bus stations and seaports). The vehicles generally ride on the networks, such as automobiles, bicycles, buses, trains, aircrafts. The operations deal with the way the vehicles are operated on the network and the procedures set for this purpose including the legal environment [(Laws, Codes, Regulations, etc.)]. Policies, such as how to finance the system (for example, the use of tolls or gasoline taxes) may be considered part of the operations.
Broadly speaking, the design of networks are the domain of civil engineering and urban planning, the design of vehicles of mechanical engineering and specialized subfields such as nautical engineering and aerospace engineering, and the operations are usually specialized, though might appropriately belong to operations research or systems engineering.
Modes and categories
Modes are combinations of networks, vehicles, and operations, and include walking, the road transport system, rail transport, ship transport and modern aviation.
Categories of transport
(Non-human) animal-powered transport is a broad category of the human use of non-human working animals (also known as "beasts of burden") for the movement of people and goods. Humans may ride some of the larger of these animals directly, use them as pack animals for carrying goods, or harness them, singly or in teams, to pull (or haul) sleds or wheeled vehicles.
Air transport
A fixed-wing aircraft, commonly called airplane or aeroplane, is a heavier-than-air craft where movement of the wings in relation to the aircraft is not used to generate lift. The term is used to distinguish from rotary-wing aircraft, where the movement of the lift surfaces relative to the aircraft generates lift. A more rare type of aircraft that is neither fixed-wing nor rotary-wing is an ornithopter. A heliplane is XXXX fixed-wing and rotary-wing.
A Cessna 177 propeller-driven general aviation aircraft
Fixed-wing aircraft include a large range of craft from small trainers and recreational aircraft to large airliners and military cargo aircraft. Some aircraft use fixed wings to provide lift only part of the time and may or may not be referred to as fixed-wing.
The current term also embraces aircraft with folding wings that are intended to fold when on the ground. This is usually to ease storage or facilitate transport on, for example, a vehicle trailer or the powered lift connecting the hangar deck of an aircraft carrier to its flight deck. It also embraces aircraft, such as the General Dynamics F-111, Grumman F-14 Tomcat and the Panavia Tornado, which can vary the sweep angle of their wings during flight. These aircraft are termed "variable geometry" aircraft. When the wings of these aircraft are fully swept, usually for high speed cruise, the trailing edges of their wings about the leading edges of their tailplanes, giving an impression of a single delta wing if viewed in plan. There are also rare examples of aircraft which can vary the angle of incidence of their wings in flight, such the F-8 Crusader, which are also considered to be "fixed-wing".
Two necessities for all fixed-wing aircraft (as well as rotary-wing aircraft) are air flow over the wings for lifting of the aircraft, and an open area for landing. The majority of aircraft, however, also need an airport with the infrastructure to receive maintenance, restocking, refueling and for the loading and unloading of crew, cargo and/or 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 jet aircraft can reach up to 875 km/h. Single-engined aircraft are capable of reaching 175 km/h or more at cruise speed. Supersonic aircraft (military, research and a few private aircraft) can reach speeds faster than sound. The record is currently held by the SR-71 with a speed of 3,529.56 km/h.
Rail
Rail transport is the transport of passengers and goods along railways or railroads. A typical railway (or railroad) track consists of two parallel steel (or in older networks, iron) rails, generally anchored perpendicular to beams (termed sleepers or ties) of timber, concrete, or steel to maintain a consistent distance apart, or gauge. The rails and perpendicular beams are usually then placed on a foundation made of concrete or compressed earth and gravel in a bed of ballast to prevent the track from buckling (bending out of its original configuration) as the ground settles over time beneath and under the weight of the vehicles passing above. The vehicles traveling on the rails are arranged in a train; a series of individual powered or unpowered vehicles linked together, displaying markers. These vehicles (referred to, in general, as cars, carriages or wagons) move with much less friction than on rubber tires on a paved road, and the locomotive that pulls the train tends to use energy far more efficiently as a result.
Road transport
An automobile is a wheeled passenger vehicle that carries its own motor. Different types of automobiles include cars, buses, trucks, and vans. Some include motorcycles in the category, but cars are the most typical automobiles. As of 2024 there were 590 million passenger cars worldwide (roughly one car for every ten people), of which 140 million in the U.S. (roughly one car for every two people) [1].
The automobile was thought of as an environmental improvement over horses when it was first introduced in the 1880s. Before its introduction, in New York City alone, more than 1,800 tons of manure had to be removed from the streets daily, although the manure was used as natural fertilizer for crops and to build top soil. In 2024, the automobile is recognized as one of the primary sources of world-wide air pollution and a cause of substantial noise pollution and adverse health effects.
Watercraft
A watercraft is a vehicle designed to float on and move across (or through) water for pleasure, physical exercise (in the case of many small boats), transporting people and/or goods, or military missions.
The common need for buoyancy unites all watercraft, and makes each one’s hull a dominant aspect of its construction, maintenance, and appearance.
Most watercraft would be described as either ships or boats; although nearly all ships are larger than nearly all boats, the distinction between those two categories is not one of size per se.
Another definition says a ship is any floating craft that transports cargo for the purpose of earning revenue; in that context, passenger ships transport "supercargo", another name for passengers or persons not working on board. However, neither fishing boats nor ferries are considered ships, though XXXX carry cargo (their catch of the day or passengers) (and for that matter lifeboats).
English seldom uses the term watercraft to describe any specific individual object (and probably then only as an affectation): rather the term serves to unify the category that ranges from small boats to the largest ships, and also includes the diverse watercraft for which some term even more specific than ship or boat (e.g., canoe, kayak, raft, barge, jet ski) comes to mind first. (Some of these would even be considered at best questionable as examples of boats.)
Ship transport
Ship transport is the process of moving people, goods, etc. by barge, boat, ship or sailboat over a sea, ocean, lake, canal or river. This is frequently undertaken for purposes of commerce, recreation or military objectives.
A hybrid of ship transport and road transport is the historic horse-drawn boat. Hybrids of ship transport and air transport are kite surfing and parasailing.
The first craft were probably types of canoes cut out from tree trunks. The colonization of Australia by Indigenous Australians provides indirect but conclusive evidence for the latest date for the invention of ocean-going craft; land bridges linked southeast Asia through most of the Malay Archipelago but a strait had to be crossed to arrive at New Guinea, which was then linked to Australia. Ocean-going craft were required for the colonization to happen.
Early sea transport was accomplished with ships that were either rowed or used the wind for propulsion, and often, in earlier times with smaller vessels, a combination of the two.
Also there have been horse-powered boats, with horses on the deck providing power [2].
Ship transport was frequently used as a mechanism for conducting warfare. Military use of the seas and waterways is covered in greater detail under navy.
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, such as the Everglades, some craft, such as the hovercraft, are propelled by large pusher-prop fans.
Although relatively slow, modern sea transport is a highly effective method of transporting large quantities of non-perishable goods. Transport by water is significantly less costly than transport by air for trans-continental shipping.
In the context of sea transport, a road is an anchorage.
Transport and communication are XXXX substitutes and complements. Though it might be possible that sufficiently advanced communication could substitute for transport, one could telegraph, telephone, fax, or email a customer rather than visiting them in person, it has been found that those modes of communication in fact generate more total interactions, including interpersonal interactions. The growth in transport would be impossible without communication, which is vital for advanced transportation systems, from railroads which want to run trains in two directions on a single track, to air traffic control which requires knowing the location of aircraft in the sky. Thus, it has been found that the increase of one generally leads to more of the other.
Transport and land use
There is a well-known relationship between the density of development, and types of transportation. Intensity of development is often measured by area of floor area ratio (FAR), the ratio of usable floorspace to area of land. As a rule of thumb, FARs of 1.5 or less are well suited to automobiles, those of six and above are well suited to trains. The range of densities from about two up to about four is not well served by conventional public or private transport. Many cities have grown into these densities, and are suffering traffic problems.
Land uses support activities. Those activities are spatially separated. People need transport to go from one to the other (from home to work to shop back to home for instance). Transport is a "derived demand," in that transport is unnecessary but for the activities pursued at the ends of trips. Good land use keeps common activities close (e.g. housing and food shopping), and places higher-density development closer to transportation lines and hubs. Poor land use concentrates activities (such as jobs) far from other destinations (such as housing and shopping).
There are economies of agglomeration. Beyond transportation some land uses are more efficient when clustered. Transportation facilities consume land, and in cities, pavement (devoted to streets and parking) can easily exceed 20 percent of the total land use. An efficient transport system can reduce land waste.
Transport in cities
Transport in cities, the ways that people and goods move through and serve the complex physical, economic and social XXXXbolism of these living organisms, presents a special case.
The city presents an unusual context for transport, mobility and policy choices because of the much higher densities of people and activities relative to the rest. This leads to a situation where environmental, economic, public health, social and quality of life considerations and constraints become at least equi-important to pure mobility objectives and requirements.
Traditionally, however, urban transport analysis, policies and the investments that follow have been lead by professional transport planners and traffic experts, who have by and large made use of the same forecasting and response tools that they have used to good effect in other transport sectors. The result of relying on these narrowly conceived, highly focused technical tools has led in most cities to a substantial overbuilding of the road and supporting infrastructure, which has purposely maximized throughput in terms of the numbers of vehicles and the speeds with which they pass through and move around in the built-up areas.
Too much infrastructure and too much smoothing of it for maximum vehicle throughput and speeds has created situations in which in many cities of the world there is not only too much traffic but also many – if not all – of the negative impacts that go with it. This is the dilemma of transport policy and practice in our cities today, with the negative results that can be clearly observed in all too many places.
It is only in recent years that these traditional practices have started to be questioned in many places, and as a result of new types of analysis which bring in a much broader range of skills than those traditionally relied on – spanning such areas as environmental impact analysis, public health, sociologists as well as economists who increasingly are questioning the viability of the old mobility solutions — we are today at a turn in the road as far as transport in cities is concerned. It is relevant to note that by and large European cities and local government are leading the way in this transition in process.
It is critically important that analytic procedures and practices in the sector are radically revised and rendered more appropriate for the emerging and very different circumstances presented by 21st century cities. First, because that’s where half of the earth’s population already is. Second because these are the areas with by far the highest growth rates. Third, most of this growth is now taking place in the Global South, whose cities are growing at rates out of control. And hand in had with this because the number of motor vehicles (including two wheeled vehicles and especially in the countries of the developing world) is exploding, leading to levels of traffic and problems which far exceed anything ever seen in the past.
Transport, energy, and the environment
Transport is a major use of energy, and transport burns most of the world’s petroleum. Hydrocarbon fuels produce carbon dioxide, a greenhouse gas widely thought to be the chief cause of global climate change, and petroleum-powered engines, especially inefficient ones, create air pollution, including nitrous oxides and particulates (soot). Although vehicles in developed countries have been getting cleaner because of environmental regulations, this has been offset by an increase in the number of vehicles and more use of each vehicle.
Other environmental impacts of transport systems include traffic congestion, toxic runoff from roads and parking lots that can pollute water supplies and aquatic ecosystems, and automobile-oriented urban sprawl, which can consume natural habitat and agricultural lands.
Low-pollution fuels can reduce pollution. Low pollution fuels may have a reduced carbon *******, and thereby contribute less in the way of carbon dioxide emissions, and generally have reduced sulfur, since sulfur exhaust is a cause of acid rain. The most popular low-pollution fuels at this time are liquefied natural gas and gasoline-ethanol blends. Hydrogen is an even lower-pollution fuel that produces no carbon dioxide, but producing and storing it economically is currently not feasible. Other alternative renewable energy sources such as biodiesel are being researched heavily.
Another strategy is to make vehicles more efficient, which reduces pollution and waste by reducing the energy use. Electric vehicles use efficient electric motors, but their range is limited by either the extent of the electric transmission system or by the storage capacity of batteries. Electrified public transport generally uses overhead wires or third rails to transmit electricity to vehicles, and is used for XXXX rail and bus transport. Battery electric vehicles store their electric fuel onboard in a battery pack. Another method is to generate energy using fuel cells, which may eventually be two to five times as efficient as the internal combustion engines currently used in most vehicles. Another effective method is to streamline ground vehicles, which spend up to 75% of their energy on air-resistance, and to reduce their weight. Regenerative braking is possible in all electric vehicles and recaptures the energy normally lost to braking, and is becoming common in rail vehicles. In internal combustion automobiles and buses, regenerative braking is not possible, unless electric vehicle components are also a part of the powertrain, these are called hybrid electric vehicles.
Shifting travel from automobiles to well-utilized public transport can reduce energy consumption and traffic congestion.
Walking and bicycling instead of traveling by motorized means also reduces the consumption of fossil fuels. While the use of these two modes generally declines as a given area becomes wealthier, there are some countries (including Denmark, Netherlands, Japan and parts of Germany, Finland and Belgium) where bicycling comprises a significant share of trips. Some cities with particularly high modal shares of cycling are Oulu (25%), Copenhagen (33%) and Groningen (50%). A number of other cities, including London, Paris, New York, Sydney, Bogotá, Chicago and San Francisco are creating networks of bicycle lanes and bicycle paths, but the value of such devices for utility cycling is highly controversial.
Research
Transport research facilities are mainly attached to universities or are steered by the state. In most countries (not in France and Spain) one can see now how laboratories are brought into PPP-operation, where industry takes over part of the share.
Some major research centres in Europe:
• CEDEX ES
• CERTU FR
• CRF IT
• Centre for Transport Studies Imperial College UK
• Delft University of Technology NL
• DLR DE
• Eidgenossische Technische Hochschule CH
• LCPC FR
• INRETS FR
• TNO NL
• Transport & Mobility Leuven BE
• Transport Research Laboratory TRL UK
• VTT FI
• Joint OECD-ECMT Transport Research Centre
• European Conference of Ministers of Transport
USA:
• https://www.its.berkeley.edu Institute of Transportation Studies, University of California, Berkeley
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