how is superconductivity applied in magnetic suspension of trains and in high speed computers?

Magnetic levitation (maglev) suspends an object so that is free of any surface contact. This has the effect of providing a frictionless contact with the ground, making it particularly appropriate for high speed trains.

            Once the train is rised in air, by continually changing the polarity of alternate magnets along the track, a series of attractions and repulsions is generated that provides the force to overcome air resistance and accelerate the train along the guide way.

There are two types of Maglev trains:
The electromagnetic suspension system (Germany) uses conventional magnets under the train on structures that wrap around the guide way to provide the lift and to create the frictionless running surface. This system is unstable, because of the varying distance between the magnets and the guide way. The instability needs to be monitored closely and computers have provided the control to correct the instability. The lifting force is produced by arrays of electromagnets of like polarity in both the train and the guide way. The magnets repel each other to lift the train above the track.
The electrodynamic suspension System (Japan) uses superconducting magnets on the vehicle and electrically conductive strips or coils on the guide way to levitate the train. This doesn’t require the same amount of computer monitoring adjustment while travelling.

2) Superconductivity is applied to electronic devices such as computers. The shrinking of computer chips are limited by the generation of heat, due to the resistance of the electrical flow required to make them run, as well as by the speed with which signals can be conducted. Superconducting film, used as connecting conductors, result in more densely packed conductor chips. These could transmit information a lot faster.