Abstract: An air purification includes a body portion, having a first installation space, a second installation space and a third installation space; a positive/negative ion module, removably mounted in the first installation space and controlled to generate positive ions and/or negative ions; a plasma module, removably mounted in the second installation space and controlled to generate plasmas; and a power supply module, removably mounted in the third installation space and configured to supply power for the positive/negative ion module and the plasma module.

Abstract: The present disclosure may provide a magnetic resonance (MR) system. The MR system may include a magnet assembly, a gradient coil assembly, and a shim assembly. The magnet assembly may be configured to generate a main magnetic field. The magnet assembly may include a magnet and a cryostat configured to cool the magnet located inside the cryostat. The cryostat may form a bore. The gradient coil assembly may be configured to generate a gradient magnetic field. The gradient coil assembly may be located inside the bore. The shim assembly may be configured to at least partially shield a stray field which is generated by the gradient coil assembly and to which the magnet is subjected. The shim assembly may be located outside the gradient coil assembly.

Abstract: Implementations of the present disclosure relate to visual programming for deep learning. A computer-implemented method comprises presenting a visual representation of an artificial neural network, the visual representation comprising graphical elements representing layers of the artificial neural network; in response to receiving a drag-and-drop operation on the graphical elements, modifying an intermediate representation of the artificial neural network, wherein the intermediate representation is independent of a deep learning framework and the drag-and-drop operation is configured to modify connections between the graphical elements; and modifying, based on the intermediate representation of the artificial neural network, code of the artificial neural network for a target deep learning framework.

Abstract: The invention discloses a durable roof structure with frost resistance and high ductility and a construction method thereof, belonging to the technical field of roofing, and comprises a base layer, a leveling layer, a flexible waterproof coating, a thermal insulation layer and a crack-resistant and frost-resistant surface layer arranged in sequence from bottom to top. The invention not only has lower requirements on construction conditions and simple operation, but also reduces the generation of large cracks, effectively improves the crack resistance and frost resistance of the roof, improves the roof structure, and is more suitable for the northern cold region.

Abstract: Embodiments of the present disclosure provides a shimming device, a magnetic assembly, and a magnetic resonance imaging (MRI) system, and a shimming method. The MRI system may include a magnet for generating a main magnetic field. The magnet may be provided with a mounting cavity. The shimming device may include a shimming structure configured to improve a magnetic field uniformity of the main magnetic field. The shimming structure may be disposed in the mounting cavity. When the MRI system replaces a gradient coil, i.e., the shimming operation may not be reperformed, which greatly reduces an operation complexity of the MRI system.

Abstract: Implementations of the present disclosure relate to visual programming for deep learning. A computer-implemented method comprises presenting a visual representation of an artificial neural network, the visual representation comprising graphical elements representing layers of the artificial neural network; in response to receiving a drag-and-drop operation on the graphical elements, modifying an intermediate representation of the artificial neural network, wherein the intermediate representation is independent of a deep learning framework and the drag-and-drop operation is configured to modify connections between the graphical elements; and modifying, based on the intermediate representation of the artificial neural network, code of the artificial neural network for a target deep learning framework.

Abstract: Magnetic resonance imaging (MRI) systems and compositions thereof are provided. The MRI systems may include a main magnet configured to generate a primary magnetic field, the primary magnet forming a bore. The MRI system may include a gradient coil arranged in the bore and configured to generate a gradient magnetic field that provides a magnetic field environment with the main magnetic field. The gradient coil may include a shielding gradient coil including two or more coil units. One of the two or more coil units may be wound along a first coil path. Another one of the two or more coil units may be wound along a second coil path. The MRI system may also include a shimming structure arranged between the gradient coil and the primary magnet and configured to homogenize the main magnetic field.

Abstract: A radiation therapy system may include a magnetic resonance imaging (MRI) device configured to acquire MRI data with respect to a region of interest (ROI). The MRI device may include a main magnet that is around a longitudinal axis and configured to generate a magnetic field. The MRI device may also include a radiation therapy device configured to perform a treatment on at least one portion of the ROI by delivering, based on the MRI data, therapeutic radiation to the at least one portion of the ROI. The radiation therapy device may be rotatable around the longitudinal axis. The MRI device may also include a first shielding structure configured to provide interference shielding for the MRI device or the radiation therapy device. The radiation therapy device may be rotatable relative to the first shielding structure around the longitudinal axis.

Abstract: The present disclosure relates to a shimming device. The shimming device may include at least one supporting component each of which is configured with a plurality of wire groove groups. Each of the plurality of wire groove groups may include a plurality of wire grooves. Each of the plurality of wire grooves may be in a closed shape. The closed shapes formed by the plurality of wire grooves may be nested. The shimming device may further include wires arranged in the wire grooves of the plurality of wire groove groups of the at least one supporting component.

Abstract: A device for testing temperature conduction and frost-heaving strain of a concrete lining canal comprises: a frost-heaving device comprising a lining canal body and a temperature control device, the temperature control device being configured to provide a predetermined temperature for the lining canal body; a detection device comprising a transverse deformation detection device, a vertical deformation detection device and a plurality of temperature sensors, the transverse deformation detection device being configured to detect a transverse frost-heaving strain parameter of the lining canal body, and the plurality of temperature sensors being arranged along an axial direction of the lining canal body, being embedded inside the lining canal body and being configured to detect temperature conduction performance of the lining canal body.

Abstract: The present invention provides a dynamic contact heat transfer simulation device for rolling heavy-load deformation zone. The device includes a control system, a data acquisition system, a pressure-adjustable fixed cold end, a rotating chuck, a temperature-adjustable heat-conducting rod and an speed-adjustable rotation hot end; the device utilizes the rotating chuck and the speed-adjustable rotating hot end to adjust the rotation speed in real time according to the actual rolling conditions, simulate the working conditions of the actual rolling heavy-load deformation zone, and accurately obtain the dynamic heat transfer coefficient of the rotating contact interface under variable load pressure conditions.

Abstract: The invention discloses an experimental apparatus and an experimental method for the negative bending moment zone of a continuous beam to bear load under chloride environment, relating to the technical field of engineering experiment, comprising a high-rigidity main frame, a loading system, an erosion system and a test beam; the test beam is detachably arranged on the high-rigidity main frame; the loading system is installed on the high-rigidity main frame and under the test beam, and is used to apply load to the test beam; the erosion system is arranged on the test beam with built-in chloride solution; the test beam is a continuous beam that meets the design requirements. The experimental apparatus provided by the invention is stable and reliable, easy to use, and can provide the experimental conditions for the wet-dry cycle and the load-bearing coupling reaction in chloride environment.

Abstract: The present disclosure relates to a shimming device. The shimming device may include at least one supporting component each of which is configured with a plurality of wire groove groups. Each of the plurality of wire groove groups may include a plurality of wire grooves. Each of the plurality of wire grooves may be in a closed shape. The closed shapes formed by the plurality of wire grooves may be nested. The shimming device may further include wires arranged in the wire grooves of the plurality of wire groove groups of the at least one supporting component.

Abstract: The invention discloses a durable roof structure with frost resistance and high ductility and a construction method thereof, belonging to the technical field of roofing, and comprises a base layer, a leveling layer, a flexible waterproof coating, a thermal insulation layer and a crack-resistant and frost-resistant surface layer arranged in sequence from bottom to top. The invention not only has lower requirements on construction conditions and simple operation, but also reduces the generation of large cracks, effectively improves the crack resistance and frost resistance of the roof, improves the roof structure, and is more suitable for the northern cold region.

Abstract: The present disclosure may provide a magnetic resonance (MR) system. The MR system may include a magnet assembly, a gradient coil assembly, and a shim assembly. The magnet assembly may be configured to generate a main magnetic field. The magnet assembly may include a magnet and a cryostat configured to cool the magnet located inside the cryostat. The cryostat may form a bore. The gradient coil assembly may be configured to generate a gradient magnetic field. The gradient coil assembly may be located inside the bore. The shim assembly may be configured to at least partially shield a stray field which is generated by the gradient coil assembly and to which the magnet is subjected. The shim assembly may be located outside the gradient coil assembly.

Abstract: The present disclosure relates to systems and methods for magnetic resonance imaging (MRI). The systems may include a gradient coil assembly configured to form a gradient magnetic field. The systems may also include a cryostat including a superconducting coil assembly and a magnetic field shielding apparatus arranged on/in a component of the cryostat. The superconducting coil assembly may be configured to form a main magnetic field. The magnetic field shielding apparatus may be configured to shield the superconducting coil assembly from a stray field of the gradient coil assembly. The magnetic field shielding apparatus may include a conductive shielding component, a shielding cylinder, or a combination thereof.

Abstract: The present disclosure relates to a shimming device. The shimming device may include at least one supporting component each of which is configured with a plurality of wire groove groups. Each of the plurality of wire groove groups may include a plurality of wire grooves. Each of the plurality of wire grooves may be in a closed shape. The closed shapes formed by the plurality of wire grooves may be nested. The shimming device may further include wires arranged in the wire grooves of the plurality of wire groove groups of the at least one supporting component.

Abstract: The present disclosure provides a method, an apparatus and a search node for warming up index files during a search service. The search service is provided by at least one search node in a search system. A first index file is stored in a disk in the search node, and a first group of pages from the first index file is stored in a cache in the search node. A second index file is stored into the disk in the search node. A plurality of queries is received during the search service. At least one warm-up query is determined from the plurality of queries. A warm-up search is performed based on the second index file in response to the at least one warm-up query. A second group of pages in the second index file is stored into the cache based on a result of the warm-up search.