摘要:
A low eddy current cryogen circuit for superconducting magnets including at least a first cooling coil made of an electrically conducting material and having at least one electrical isolator incorporated in the first cooling coil. The electrical isolator is located to inhibit induced eddy current loops due to inductive coupling of the first cooling coil with eddy current inducing field sources.
摘要:
A rotating machine comprising a superconductive coil and a temperature sensor operable to provide a signal representative of superconductive coil temperature. The rotating machine may comprise a control system communicatively coupled to the temperature sensor. The control system may be operable to reduce electric current in the superconductive coil when a signal representative of a defined superconducting coil temperature is received from the temperature sensor.
摘要:
A cryogen free superconducting magnet assembly having a high Tc superconducting magnet and a thermal reservoir in thermal contact with the high Tc superconducting magnet. A method of cooling a cryogen free superconducting magnet assembly and an MRI system having cryogen free superconducting magnet assemblies.
摘要:
A system and method for protecting a superconductor from a quench condition. A quench protection system is provided to protect the superconductor from damage due to a quench condition. The quench protection system comprises a voltage detector operable to detect voltage across the superconductor. The system also comprises a frequency filter coupled to the voltage detector. The frequency filter is operable to couple voltage signals to a control circuit that are representative of a rise in superconductor voltage caused by a quench condition and to block voltage signals that are not. The system is operable to detect whether a quench condition exists in the superconductor based on the voltage signal received via the frequency filter and to initiate a protective action in response.
摘要:
This Implant (1) includes, in a known manner, two pieces (2, 3) that are telescopically mobile relative to one another and elements (4) for positioning one piece (3) in a particular position relative to the other piece (2), the two pieces (2, 3) being made from a polymer material. At least one of the two pieces (2, 3) has a plurality of micro-cavities (15, 20, 32) over at least one wide portion of its peripheral wall (5); and the implant includes internal communications (16, 21, 33) in its wall(s) (5, 7, 31) including the micro-cavities (15, 20, 32), connecting all or some of the micro-cavities to one another.
摘要:
This Implant (1) includes, in a known manner, two pieces (2, 3) that are telescopically mobile relative to one another and elements (4) for positioning one piece (3) in a particular position relative to the other piece (2), the two pieces (2, 3) being made from a polymer material. At least one of the two pieces (2, 3) has a plurality of micro-cavities (15, 20, 32) over at least one wide portion of its peripheral wall (5); and the implant includes internal communications (16, 21, 33) in its wall(s) (5, 7, 31) including the micro-cavities (15, 20, 32), connecting all or some of the micro-cavities to one another.
摘要:
This system includes a retaining housing formed by a hole intended to receive the anchoring member and a retaining portion arranged on the anchoring member; said retaining housing is arranged in a part having a degree of elastic flexibility and is delimited by a continuous wall of this part; the retaining housing, on the side of a first axial end, forms a first collar forming a continuous circular projection capable of being elastically deformed by the retaining portion arranged on the anchoring member; the wall of said part delimiting the retaining housing also forms, on a second axial end, a second collar not able to be elastically deformed by said retaining portion.
摘要:
A system for connecting a spinal osteosynthesis rod and a crossbar include a passage for receiving the crossbar and hinge mounted jaws for clamping the rod. A locking device biases the crossbar against the jaws. A return spring pulls the jaws relatively close to one another independently of the crossbar such that the jaws may clamp the osteosynthesis rod to ensure a stable mounting of the connection system to the osteosynthesis rod.
摘要:
A discrete multitone stacked-carrier spread spectrum communication method is based on frequency domain spreading including multiplication of a baseband signal by a set of superimposed, or stacked, complex sinusoid carrier waves. In a preferred embodiment, the spreading involves energizing the bins of a large Fast Fourier transform (FFT). This provides a considerable savings in computational complexity for moderate output FFT sizes. Point-to-multipoint and multipoint-to-multipoint (nodeless) network topologies are possible. A code-nulling method is included for interference cancellation and enhanced signal separation by exploiting the spectral diversity of the various sources. The basic method may be extended to include multielement antenna array nulling methods for interference cancellation and enhanced signal separation using spatial separation. Such methods permit directive and retrodirective transmission systems that adapt or can be adapted to the radio environment. Such systems are compatible with bandwidth-on-demand and higher-order modulation formats and use advanced adaptation algorithms. In a specific embodiment the spectral and spatial components of the adaptive weights are calculated in a unified operation based on the mathematical analogy between the spectral and spatial descriptions of the airlink.