Abstract: A gallium nitride power device, including: a gallium nitride substrate; cathodes; a plurality of gallium nitride protruding structures arranged on the gallium nitride substrate and between the cathodes, a groove is formed between adjacent gallium nitride protruding structures; an electron transport layer, covering a top portion and side surfaces of each of the gallium nitride protruding structures; a gallium nitride layer, arranged on the electron transport layer and filling each of the grooves; a plurality of second conductivity type regions, where each of the second conductivity type regions extends downward from a top portion of the gallium nitride layer into one of the grooves, and the top portion of each of the gallium nitride protruding structures is higher than a bottom portion of each of the second conductivity type regions; and an anode, arranged on the gallium nitride layer and the second conductivity type regions.

Abstract: The present disclosure relates to a skywave large-scale MIMO communication method, model, and system. A skywave communication base station in a short waveband is constructed using a large-scale antenna array, wherein skywave large-scale MIMO communication is carried out between the skywave communication base station and a user terminal in a coverage area by ionospheric reflection. The skywave communication base station determines a spacing of the large-scale antenna array according to a maximum operating frequency, and communicates with the user terminal based on a TDD communication mode, wherein a skywave large-scale MIMO signal is transmitted based on an OFDM modulation mode or a power efficiency improvement modulation mode. The skywave communication base station selects a communication carrier frequency within a short waveband range according to a real-time ionospheric channel characteristic, and adaptively selects an OFDM modulation parameter and a signal frame structure.

Abstract: A virtual scene interactive rehabilitation training robot based on a lower limb connecting rod model and force sense information and a control method thereof are disclosed. The thigh, calf and foot of a leg of a human body are equated to a three-connecting rod series-connected mechanical arm. A human body leg gravity compensation model is constructed. The leg posture of a patient is detected by Kinect. An interaction force between a limb of the patient and a rehabilitation robot is detected by a force sensor on the rehabilitation robot. Then, a progressive rehabilitation training method is designed for the model. According to a set weight reduction ratio, the motion of the rehabilitation robot is controlled by judging plantar force data.

Abstract: A biomass-based long-chain alcohol ether oxygenated additive and a preparation method and application thereof are disclosed. The additive used agricultural and forestry wastes as raw materials, and has a general chemical formula of R—(O—C1-3)n—R—OH. The preparation method includes the following steps: step 1, performing drying pretreatment on biomass raw materials, performing rapid pyrolysis under an inert atmosphere to obtain a pyrolysis product containing water, gases, water-phase bio-oil and oil-phase bio-oil, separating out the water-phase bio-oil and performing catalytic hydrogenation on the water-phase bio-oil to obtain polyols; step 2, performing catalytic dehydration on the polyols obtained in step 1 under a basic catalyst system to obtain epoxyalkane; and step 3, making the epoxyalkane obtained in step 2 and methanol undergo a reaction under a molecular sieve catalyst and removing the solid catalyst by separation to obtain the long-chain alcohol ether oxygenated additive.

Abstract: A processing method for perennially and deeply polluted sludge containing oils and water, waste residues, or oil sands in natural oil mines, and a processing system thereof. In the method, a solid substance containing oils and water is in full contact with an organic liquid solvent with a low boiling point and a weak polarity or no polarity at room temperature under pressurized condition to extract oil and water from the solid substance to the liquid, the organic solvent with low boiling point and low latent heat is easily separated from oil and water in the liquid after solid-liquid separation by decompression or heating evaporation, the gas solvent is compressed and condensed for recycling, the extracted oil and water are subjected to oil-water separation, and the extracted oil may be used as fuel or used for refining.

Abstract: A laterally double-diffused metal oxide semiconductor device is provided, including: a drift region (3) having a first conductivity type; a first body region (10) disposed on the drift region (3) and having a second conductivity type, the first conductivity type and the second conductivity type being opposite conductivity types; a first conductivity type region (13) disposed in the first body region (10); a second body region (12) disposed in the first conductivity type region (13) and having the second conductivity type; a source region (11) disposed in the second body region (12) and having the first conductivity type; and a contact region (9) disposed in the first body region (10) and having the second conductivity type.

Abstract: Disclosed is a method for setting parameters of a load feedforward controller for superheated steam temperature control, which belongs to the technical field of thermal automatic control. This method adds a load feedforward controller to the conventional boiler superheated steam temperature spray desuperheating cascade control system. The application provides a structure of the load feedforward controller, and a method for designing the parameters of the load feedforward controller according to the dynamic characteristics of the superheated steam temperature related to feed coal flow disturbance, feedwater flow disturbance and desuperheating water spray disturbance. The method of the application could effectively reduce the superheated steam temperature deviation in the process of unit load rise or drop, and the design method is simple, effective and easy to realize in engineering.

Abstract: The present invention discloses a care robot controller, which includes: a controller body that includes slide rails, finger slot sliders and a joystick, wherein the finger slot sliders are movably arranged on the slide rails and configured to receive pressing, and the joystick is configured to control the care robot; a gesture parsing unit configured to parse three-dimensional gestures of the controller body, and control the care robot to perform corresponding actions when the three-dimensional gestures of the controller body are in line with preset gestures; and a tactile sensing unit configured to sense the pressing received by the finger slot sliders and initiate a user mode corresponding to the pressing information, so that the controller body provides corresponding vibration feedback. Thus the user can control the controller efficiently and conveniently, the control accuracy is improved, and effective man-machine interaction is realized.

Abstract: Disclosed is a method for estimating dense multipath parameters by means of multipolarized broadband extended array responses, which includes: first transmitting multiple different transmitted signal sequences via a multipolarized antenna array, and processing received data in multiple snapshots according to the known transmitted signals, to obtain channel responses of multipolarized antenna components at all frequency points in a frequency band; extending the obtained channel response matrixes of multiple frequency points in multiple snapshots into a large two-dimensional channel response matrix; then, acquiring a delay parameter regarding multipath propagation by using a reference array element, and estimating two-dimensional departure and arrival angles by using a channel matrix subjected to frequency domain smoothing and dimensionality reduction; and afterwards, pairing the estimated departure and arrival angles, and estimating parameters such as the cross-polarization ratios, the initial phases, and the

Abstract: The present invention discloses a high-precision and miniaturized on-orbit calibration device for a six-dimensional force sensor of a space station manipulator and a calibration method thereof, which include an inverted ? shape fixing bracket, three force applying devices, and a cubic stress block. Each force applying device includes a force applying head, a single axis force sensor, a force source part and a fastening part. The force source part includes an upper support plate, a second electrode plate, piezoelectric ceramic plates, a first electrode plate and a lower support plate, which are coaxially arranged sequentially from top to bottom. The single axis force sensor is mounted on the top of the upper support plate, and the hemispherical force applying head is mounted on the top of the single axis force sensor. The cubic stress block is mounted on the top of the six-dimensional force sensor.

Abstract: A low-loss feeding network comprises a vertical switching structure, a substrate integrated waveguide (SIW), a 2N-way power divider, coupling slots, matching metal vias and parallel-plane waveguides, wherein the energy provided by a standard waveguide is coupled to the SIW through the vertical switching structure, and the energy outputted by the SIW is evenly split into 2N parts by the 2N-way power divider; the energy of each way outputted by the 2N-way power divider is coupled to parallel-plane waveguides through the coupling slots and the matching metal vias, and the electric field at the junction of two adjacent parallel-plane waveguides is zero, so that an ideal virtual electric wall is formed, thus the structure of the feeding network is simplified, and the metal loss at the junction is reduced; finally, the energy provided by the low-loss feeding network is radiated in phase through the symmetrical slot antenna array.

Abstract: A whisker sensor includes an upper circuit board, a lower circuit board, a flexible whisker, and a magnet. The magnet is fixed to the flexible whisker through a central through hole, and the location of the magnet changes with the swinging of the whisker; the upper and lower circuit boards are identical in shape and size, and are connected through an upright column. A circular hole is formed at the center of the upper circuit board, four Hall sensors are symmetrically distributed on the edge of the circular hole, and the displacement of the whisker in X and Y directions can be obtained by detecting the change in magnetic field generated by the change in location of the magnet; a contact sensor is mounted on the lower circuit board, and is connected to the whisker through a connecting piece, to detect displacement of the whisker in the Z direction.

Abstract: The invention discloses a power network flexible controller topology shared by modules. Each single-phase topology comprises an AC/AC converter including N1 CHB modules, and an AC/DC module including N?N1 full-bridge rectifiers; the AC input terminals of N1 CHB modules are connected in series to form an AC port on one side of the AC/AC converter, the AC output terminals of N1 CHB modules are connected in series to form the AC port on the other side of the AC/AC converter, the AC input terminals of N?N1 full-bridge rectifiers are connected in series to form the AC port of the AC/DC module, the AC port on one side of the AC/AC converter is connected in series with the AC side port of the AC/DC module and then connected to a first AC network nd the AC port on the other side of the AC/AC converter is connected in series with the DC side port of the AC/DC module.

Abstract: The present invention discloses a biodetector based on an interference effect of a thin film with ordered porous nanostructures. The biodetector includes a detection cell, a sensing unit disposed in the detection cell, and an optical fiber spectrometer for detecting reflectometric interference spectra of the sensing unit, wherein the sensing unit is an ordered porous thin film provided with three-dimensional ordered nanopores, and diameters of the nanopores are 20 nm-500 nm. The present invention further discloses a method for using the biodetector to detect biomolecules.

Abstract: A method for preparing a porous nano-fiber heterostructure photocatalytic filter screen includes: preparing a noble metal nanostructure with tunable spectra and a heterostructure composite photocatalyst of a photocatalytic material; and preparing a large area and multilayer porous nano-fiber filter screen structure, while utilizing a scattering enhancement effect of metal nanoparticles in an porous optical fiber to realize repeated conduction of sunlight in the optical fiber and finally interact with the composite photocatalyst on a surface to improve photocatalytic efficiency.

Abstract: A converter parameterized constant admittance modeling method based on a cross initialization including the following steps: (1) performing parameterized modeling on a converter, wherein switches are modeled using a parametric historical current source constant admittance model and other components are modeled using a traditional electromagnetic transient simulation integral model in the converter; (2) detecting whether state switching occurs, performing cross initialization correction when occurring; (3) determining model parameters, and establishing an equivalent admittance matrix and an injection current source of a whole grid, to obtain an electromagnetic transient simulation equivalent model; (4) solving a network tide according to a basic solving equation I=YU to obtain an electromagnetic transient model simulation result of the converter at current time; and (5) calculating an equivalent admittance matrix and an injection current source at next time through a current network state quantity, and returni

Abstract: A compact dual-band triple-polarized antenna based on shielded mushroom structures includes a vertically-polarized radiator and a horizontally-polarized radiator. Two parts are fixedly connected in a disc-shaped structure. The vertically-polarized radiator and the horizontally-polarized radiator are both multilayer structures. Each multilayer structure includes a plurality of concentric circles, and the plurality of concentric circles include a plurality of dielectric substrates. The vertically-polarized radiator and horizontally-polarized radiator each include a plurality of shielded mushroom cell structures. Each shielded mushroom cell structure includes at least three metal layers and a metallic shorting pin, and the metallic shorting pin connects at least two of the at least three metal layers.

Abstract: A converter parameterized constant admittance modeling method based on a cross initialization including the following steps: (1) performing parameterized modeling on a converter, wherein switches are modeled using a parametric historical current source constant admittance model and other components are modeled using a traditional electromagnetic transient simulation integral model in the converter; (2) detecting whether state switching occurs, performing cross initialization correction when occurring; (3) determining model parameters, and establishing an equivalent admittance matrix and an injection current source of a whole grid, to obtain an electromagnetic transient simulation equivalent model; (4) solving a network tide according to a basic solving equation I=YU to obtain an electromagnetic transient model simulation result of the converter at current time; and (5) calculating an equivalent admittance matrix and an injection current source at next time through a current network state quantity, and returni

Abstract: A large-scale MIMO (Multiple-Input Multiple-Output) wireless transmission method for millimeter wave/Terahertz networks is provided. In order to reduce the interruption of propagation in the millimeter wave/Terahertz band, a plurality of cells are combined into a wireless transmission network, the base station in each cell is equipped with a large-scale antenna array, and a unitary transformation matrix is used to achieve large-scale beam coverage for user terminals in the entire network. Moreover, in order to reduce the influence of the multipath and Doppler effects on transmission performance, received signals are synchronized for time and frequency in each receiving beam of a user terminal. The method allocates power for signal transmission according to the statistic information of synchronized equivalent channels, and gives an optimal power allocation matrix by iterative solution based on the CCCP (concave-convex procedure) and the deterministic equivalent method.

Abstract: A natural human-computer interaction system based on multi-sensing data fusion comprises a MEMS anti tracking device, a visual tracking device, a force feedback device and a PC terminal. The MEMS arm tracking device is composed of three sets of independent MEMS sensors for collecting arm joint angle information and measuring an arm motion trajectory. The visual tracking device is composed of a binocular camera for collecting image information and measuring a finger motion trajectory. The force feedback device is mounted in a palm of an operator for providing a feedback force to the finger. The PC terminal comprises a data display module, an arm motion calculating module, an image processing module, a mechanics calculating module and a virtual scene rendering module. The system tracks the arm motion trajectory and the finger motion trajectory of the operator and provides force feedback interaction to the finger of the operator.