一个不能忘记的人:about the Maglev train in shanghai

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The world's first commercial application of a high-speed maglev line is the IOS (initial operating segment) demonstration line in Shanghai that transports people 30 km (18.6 miles) to the airport in just 7 minutes 20 seconds (top speed of 431 km/h or 268 mph, average speed 250 km/h or 150 mph). Other maglev applications worldwide are being investigated for feasibility.

maglev train

Maglev can also mean general magnetic levitation.

Transrapid at the Emsland test facility
Maglev in Shanghai
Inside the Shanghai maglevMagnetic levitation transport, or maglev, is a form of transportation that suspends, guides and propels vehicles via electromagnetic energy. This has advantages in terms of speed and ride comfort compared to wheeled mass transit systems - potentially, maglevs could reach velocities comparable to turboprop and jet aircraft (500 to 580 km/h) - but although the idea is decades old, technological and economic limitations have caused relatively few full-scale systems to be built. Maglev technology has minimal overlap with wheeled train technology and is not compatible with conventional railroad tracks.

Because they cannot share existing infrastructure, maglevs must be designed as complete transportation systems. The term "maglev" refers not only to the vehicles, but to the vehicle/guideway interaction; each being a unique design element specifically tailored to the other to create and precisely control magnetic levitation.

The various technological approaches to maglev can be very similar or very different, depending upon the manufacturer. World leader in maglev technology is Germany's Siemens and ThyssenKrupp with its Transrapid system.

Due to the lack of physical contact between the track and the vehicle, the only friction exerted is that between the vehicles and the air. Consequently maglevs can potentially travel at very high speeds with reasonable energy consumption and noise levels. Systems have been proposed that operate at up to 650 km/h (404 mph), which is far faster than is practical with conventional rail transport. The very high maximum speed potential of maglevs make them competitors to airline routes of 1,000 kilometers (600 miles) or less. The world's first commercial application of a high-speed maglev line is the IOS (initial operating segment) demonstration line in Shanghai that transports people 30 km (18.6 miles) to the airport in just 7 minutes 20 seconds (top speed of 431 km/h or 268 mph, average speed 250 km/h or 150 mph). Other maglev applications worldwide are being investigated for feasibility.

The futurist American writer, Allan Silliphant, has proposed a fundamental model of urban metro transit that addresses the problem of going from a central point such as a city center, or an airport, to various points on the periphery of a circle around that center. Using Los Angeles, as an example, it can take 2.5 hours to cross the city by auto. This is true of most very large world cities. A deeply constructed maglev radial system, below any existing structures or utilites, can be bored out in virgin bedrock or undisturbed sediment. With a depth of 200 to 300 feet it would be possible to go almost anywhere in most metro areas. A transfer point in the middle will reduce the number of trains needed. Non-stop, cross-metro tubes could also be constructed, next to the tube terminating in the center hub, avoiding a transfer. Present maglev speeds of even 200 miles/hour will greatly facilitate movement within an urban center. Surface maglev trains can continue the outbound movement to the next urban center where a similar "hub and spoke" maglev deep tube system can be established. This can save many billions in fossil fuel consumption, especially if very quick access can be provided at the stations to rental cars and timely connection to public transport on the surface.