Electricity: magnetically operated switches – magnets – and electr – Magnets and electromagnets – Magnet structure or material
Patent
1999-10-20
2000-10-31
Donovan, Lincoln
Electricity: magnetically operated switches, magnets, and electr
Magnets and electromagnets
Magnet structure or material
324319, G01V 300, H01F 500
Patent
active
061409006
ABSTRACT:
Asymmetric, compact superconducting magnets for magnetic resonance imaging are provided. The magnets have a homogeneous region (the "dsv") which can be located close to one end of the magnet so as to reduce the sensation of claustrophobia experienced by patients undergoing MRI procedures. The magnets can be designed using a hybrid process in which current density analysis is performed to obtain an initial coil configuration which is then refined using non-linear optimization techniques to obtain a final coil configuration. The hybrid method can incorporate various constraints, including, the location and size of the dsv, the uniformity and strength of the B.sub.0 field, stray field strengths outside of the superconducting magnet, and field strengths within the magnet's coils. The hybrid technique can also be used to design compact symmetric superconducting magnets.
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Crozier Stuart
Doddrell David M.
Zhao Huawei
Barrera Raymond
Donovan Lincoln
Klee Maurice M.
The University of Queensland
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