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, 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, trains, airplanes. The operations deal with the control of the system, such as traffic signals and ramp meters, railroad switches, air traffic control, etc, as well as policies, such as how to finance the system (for example, the use of tolls or gasoline taxes).
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 of transport
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
- Aviation
- Cable transport
- Conveyor transport
- Human-powered transport
- Hybrid transport
- Motorized road transport
- Pipeline transport
- Rail transport
- Ship transport
- Space transport
- Transport on other planets
- Proposed future transport
Transport and communications
Transport and communication are both 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, activities and land use
There is a well-known relationship between the density of development, and types of transportation. Density is defined as area of floorspace per area of land. As a rule of thumb, densities of 1.5 or less are well suited to automobiles. Densities 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. Personal rapid transit might fill this gap.
