Abstract: Disclosed are method and apparatus for SAR image recognition based on multi-scale features and broad learning. A region of interest of an original SAR image is extracted by centroid localization, the image is rotated and added with noise for enhancing the data volume, the image is downsampled, LBP features and PPQ features are extracted, an LBP feature vector XLBP and an LPQ feature vector XLPQ are cascaded to achieve dimension reduction by principal component analysis to obtain a fusion feature data Xm, the fusion feature data Xm is input to a broad learning network for image recognition and a recognition result is output. By fusing the LBP features and the LPQ features, complementary information is fully utilized and redundant information is reduced. The broad learning network is used to improve the training speed and reduce the time cost. As a result, the recognition effect is more stable, robust and reliable.

Abstract: We describe a superconducting magnet system for generating a uniform magnetic field. The system has at least three magnets in two sets, a first of the sets comprising an oppositely disposed pair of superconducting magnets, a second of the sets comprising at least one further magnet. The further magnet is disposed such that there exists a 3D region in which a magnet field produced by the further magnet is substantially parallel to a magnetic field produced by the pair of superconducting magnets. One of the sets of magnets is configured to produce first, bulk component of the magnetic field in the 3D region and a second of the sets of magnets is configured to produce a correction to the bulk component of the magnetic field in the 3D region to reduce a non-uniformity of the bulk component of the magnetic field in the 3D region.

Abstract: We describe a superconducting magnet system for generating a uniform magnetic field. The system has at least three magnets in two sets, a first of the sets comprising an oppositely disposed pair of superconducting magnets, a second of the sets comprising at least one further magnet. The further magnet is disposed such that there exists a 3D region in which a magnet field produced by the further magnet is substantially parallel to a magnetic field produced by the pair of superconducting magnets. One of the sets of magnets is configured to produce first, bulk component of the magnetic field in the 3D region and a second of the sets of magnets is configured to produce a correction to the bulk component of the magnetic field in the 3D region to reduce a non-uniformity of the bulk component of the magnetic field in the 3D region.