Abstract: Provided is a system of generating multi-style learning tutorials based on learning preference evaluation. The system dynamically explores preferences of learners in a learning process from a time dimension through a proposed deep reinforcement learning model, so that a deep reinforcement learning agent can accurately express learning behavior features of learners and realize the personalized and accurate construction of course tutorials. At the same time, using an internal knowledge base and an external knowledge base as resource support, a multi-modal knowledge map with a plurality of definition relationships is designed to overcome the limitations of construction of a course tutorial method.

Abstract: A semiconductor apparatus and a method of manufacturing the same are provided. A semiconductor apparatus includes a first nitride semiconductor layer, a second nitride semiconductor layer, an electrode, a dielectric structure, a field plate, a plurality of height compensators, and a plurality of vias. The second nitride semiconductor layer is on the first nitride semiconductor layer and has a bandgap greater than that of the first nitride semiconductor layer. The electrode contacts the second nitride semiconductor layer. The dielectric structure is disposed on the second nitride semiconductor layer and covers the electrode. The field plate is in the dielectric structure. The height compensators are in the dielectric structure and are disposed on the electrode and the field plate, respectively. The vias extend into the dielectric structure and contact top surfaces of the height compensators, respectively.

Abstract: A scheduling method and system for the operation of reservoirs to recharge freshwater for repelling saltwater intrusion under changing conditions. Research data of a research area is collected, the research area is generalized, and the river network topology of the area is constructed; the research data acquire the seawater flow data of each station in the research area for N time periods, analyze the correlation between the flow of a predetermined station and the saltwater intrusion and build a seawater flow spatial-temporal evolution model; rainfall data and freshwater runoff of each station are acquired to analyze the variation trends of freshwater flow and hydrological regime of each station and a first ending point and build a freshwater flow spatial-temporal evolution model; and a scheduling model for recharging freshwater for repelling saltwater intrusion is built for simulation, a scheduling method is provided, and a scheduling scheme set is formed.

Abstract: The present invention provides a foldable bathtub tray, including a first support plate and a second support plate, where the first support plate and the second support plate are hinged by using a connection assembly; the connection assembly includes a first connection seat, a second connection seat, and a rotating shaft; the first connection seat includes a first sub-seat and a second sub-seat, and the first sub-seat extends to form a limiting flange in a direction of the second sub-seat; and a part of a side wall of the second connection seat fits with an inner wall of the limiting flange. The side wall of the second connection seat abuts against the inner wall of the limiting flange to implement self-locking.

Abstract: A coupling structure for a cart comprises a first connector, a second connector, and a third connector. The first connector is detachably connected to the second connector, and the second connector is detachably connected to the third connector. The first connector is located inside the second connector, and the second connector is located inside the third connector, such that the first connector, the second connector, and the third connector form a three-layer ring-shaped embedded structure. According to the embodiments of the present disclosure, the coupling structure is stable, and has a strong bearing capacity. The cart using the coupling structure can load more objects, and has a stronger bearing capacity.

Abstract: The invention provides an oligosaccharide debranching enzyme mutant and use thereof in a glucose mother liquor. The mutant is obtained by mutating valine at position 219 in SEQ ID NO: 1 into alanine. According to oligosaccharide debranching enzyme mutant V219A, a primary mother liquor, a secondary mother liquor, or a tail liquid after chromatographic separation is used as a substrate, the percentage contents of glucose in the products are 99.21% (primary mother liquor), 98.89% (secondary mother liquor) and 97.97% (tail liquid after chromatographic separation) respectively, which are 2.86%, 8.64%, and 28.67% higher than that of glucose obtained with the wild-type oligosaccharide debranching enzyme. Therefore, the mutant V219A obviously improves the percentage content of glucose in the glucose mother liquor, and the scope of application of the mother liquor can be expanded by the high product purity and substrate conversion rate, so the mutant V219A has higher industrial application value.

Abstract: An acoustic wave device comprises a piezoelectric substrate, interdigital transducer electrodes having an electrode pitch ?0, and first and second reflector gratings disposed on opposite respective sides of the interdigital transducer electrodes in a propagation direction of a main acoustic wave through the acoustic wave device, the first reflector grating having a reflector electrode pitch ?1 throughout an entirety of the first reflector grating that is different than a reflector electrode pitch ?2 throughout an entirety of the second reflector grating to suppress ripples in a conductance curve of the acoustic wave device.

Abstract: A semiconductor package comprises a lead frame, a chip, and a molding encapsulation. The lead frame comprises a top plate, a plurality of drain pads, a plurality of slanted sections, a gate pad, and a plurality of source pads. The top plate of the lead frame comprises a thicker region and a thinner region. Each slanted section of the plurality of slanted sections connects a respective drain pad of the plurality of drain pads to the top plate. A respective side surface of each drain pad of the plurality of drain pads is exposed from a side surface of the molding encapsulation. A respective bottom surface of each drain pad of the plurality of drain pads is exposed from a bottom surface of the molding encapsulation. A top surface of the thicker region is exposed from a top surface of the molding encapsulation.

Abstract: According to a non-isolated DCDC resonant conversion control circuit provided in embodiments of this application, an inductor and a capacitor that are resonant are connected in series, so that a current flowing through the inductor is a sine waveform. A waveform coefficient of the sine wave is small, and a conduction loss of the sine wave is low. Therefore, the circuit provided in embodiments of this application can significantly reduce a circuit loss. According to the non-isolated DCDC resonant conversion control method provided in embodiments of this application, not only a phase shift angle can be adjusted to enable a switching transistor to implement zero voltage switching (ZVS) on, but switching frequency can also be adjusted. Therefore, ranges in which a voltage and power of an output interface can be adjusted are large, so that non-isolated wide-range DCDC resonant conversion is implemented.

Abstract: A coupling structure for a cart comprises a first connector, a second connector, and a third connector. The first connector is detachably connected to the second connector, and the second connector is detachably connected to the third connector. The first connector is located inside the second connector, and the second connector is located inside the third connector, such that the first connector, the second connector, and the third connector form a three-layer ring-shaped embedded structure. According to the embodiments of the present disclosure, the coupling structure is stable, and has a strong bearing capacity. The cart using the coupling structure can load more objects, and has a stronger bearing capacity.

Abstract: Wire grid polarizer and manufacturing method thereof are provided, the wire grid polarizer includes: substrate; first wire grid formed on substrate, including first wire grid reflection strips arranged parallel to each other and at equal intervals; second wire grid formed at a side of first wire grid away from substrate, including second wire grid reflection strips arranged in parallel to each other and at equal intervals; second wire grid reflection strips are in one-to-one correspondence with first wire grid reflection strips; orthographic projections of second wire grid reflection strip onto substrate falls within orthographic projections of corresponding first wire grid reflection strip onto substrate; wire width of second wire grid reflection strip is less than that of first wire grid reflection strip; and wire spacing of second wire grid reflection strip is greater than that of the first wire grid reflection strip.

Abstract: A light-emitting diode substrate, a manufacturing method thereof, and a display device are disclosed. The manufacturing method of the light-emitting diode substrate includes: forming an epitaxial layer group of M light-emitting diode chips on a substrate; transferring N epitaxial layer groups on N substrates onto a transition carrier substrate, the N epitaxial layer groups on the N substrates being densely arranged on the transition carrier substrate; and transferring at least part of N*M light-emitting diode chips corresponding to the N epitaxial layer groups on the transition carrier substrate onto a driving substrate, an area of the transition carrier substrate is greater than or equal to a sum of areas of the N substrates, M is a positive integer greater than or equal to 2, and N is a positive integer greater than or equal to 2.

Abstract: Provided is a three-phase system V2O3/VN/Mo2C nanoelectrode material, and a preparation method and application thereof. The nanoelectrode material comprises V2O3 particles, VN particles, and Mo2C particles. The V2O3 particles, VN particles, and Mo2C particles are interlaced in lattice stripes and are uniformly distributed. The mass ratio of the V2O3, VN and Mo2C is (1 to 4):(10 to 40):(4 to 16). The above-mentioned three kinds of nanoparticles are intertwined to form more incoherent interface area. The increase in the area of the incoherent interface area will cause more defects, so that more active sites are provided, and the hydrogen production performance is improved.

Abstract: The present application provides an image processing method, an image processing device, a computer storage medium and a terminal, the image processing method includes: determining convolution kernels of at least two sizes for feature extraction; performing sparsity constraint for the determined convolution kernels of at least two sizes for feature extraction through a preset objective function; and performing feature extraction on an image based on the convolution kernels subjected to the sparsity constraint.