Abstract: In a method for designing a high-rigidity blade based on stochastic isogeometric analysis, the models of stochastic fields of the material property and the external load of the blade are established based on manufacturing conditions and service environment of the blade; an optimization model of the blade is established according to high-rigidity design requirements of the blade and a constraint condition of lift-drag ratio, which is then solved. In the solution procedure, a stochastic isogeometric analysis method is used to calculate the stochastic displacement of the blade under the influence of the randomness of the material property and the external load, and the maximum lift-drag ratio of the blade airfoil is also calculated, based on which the fitness values of individuals in the current population are calculated, so that the high-rigidity design of the blade is realized in the premise of ensuring the lift-drag ratio.

Abstract: Provided is an intersection deadlock identification method for a mixed flow of autonomous vehicles. This method considers the reality that the intersection traffic flow is composed of human driven vehicles and connected autonomous vehicles. Firstly, the two-dimensional coordinates, speed and front wheel steering angle information of all vehicles in the intersection are obtained, and the blockage graph of vehicles is constructed on the assumption that the front wheel steering angles of all vehicles are fixed. If there is no ring structure in the blockage graph, there is no deadlock; if there is a ring structure, the evasion distance propagation algorithm is used to calculate the evasion requirement distance of a vehicle in the ring. When the evasion requirement distance is greater than the permitted travelling distance of the vehicle itself, a weak traffic deadlock exists.

Abstract: A method for configuring and updating random access resources in a multi-antenna multiple-input multiple-output (MIMO) environment is provided, including: initializing a base station; broadcasting, by the base station, the available RACH resources using an SIB2; initiating, by users who have data to be sent in an uplink, random access processes on the RACH resources configured by the base station; and redefining an S state, an I state, and a C state. Configuration of the RACH resources may be gradually and dynamically optimized according to the quantity of antennas of the base station and a utilization rate threshold of the RACH resources, so that waste of random access RACH resources is reduced provided that an MIMO system meets a required user/service access success probability; a utilization of the resources is improved by fully utilizing spatial diversity characteristics of the MIMO system.

Abstract: A system for use in carbon negative emission methods, a nitrogen oxide ultra-low emission system, an air supply device and a flow control module. The system for use in carbon negative emission methods enables biomass to produce inorganic carbon and pyrolysis gas/gasification gas to realize negative emission of carbon. The nitrogen oxide ultra-low emission system enables fuel to be in mixed combustion with the pyrolysis gas/gasification gas to remove nitrogen oxides, which realizes ultra-low emission of the nitrogen oxides. The air supply device is in communication with a biomass pyrolysis coupling partial gasification and is in communication with the system for use in carbon negative emission methods and the nitrogen oxide ultra-low emission system. The pyrolysis gas/gasification gas enters the nitrogen oxide ultra-low emission system.

Abstract: A transfer impedance calibration device for transducers based on spatial frequency domain smoothing technology is provided. The calibration device comprises a signal transmitter, a power amplifier, a transducer pair, a measurement amplifier, a signal collector, a measurement processor and a current sampler. The device extracts acoustic channel information through the sound filed spatial information or measurement method to design a spatial domain smoothing filter, and then comprehensively processes the transmitted current signal and the received signal through the spatial frequency domain smoothing technology to obtain the transfer impedance of the transducer pair.

Abstract: A weakly paired image style transfer method based on a pose self-supervised generative adversarial network, relating to the field of image processing. The method is suitable for style transfer of weakly paired images, different styles of pictures having certain overlap are used to perform model training of an adversarial neural network, so that the model is insensitive to poses and focuses on style learning, and therefore, in an actual application process, a source style can be converted into a target style, but a pose is kept unchanged. In addition, in the model training process of the adversarial neural network, a differentiable pose solver capable of estimating a relative pose of any two images is introduced, a phase correlation algorithm is optimized to be differentiable, and the phase correlation algorithm is embedded into an end-to-end learning network framework to achieve pose estimation.

Abstract: The present disclosure relates to a searchable encrypted data sharing method and system based on blockchain and homomorphic encryption, which protects security of sensitive data on the blockchain and realizes searchable and homomorphic calculation of data ciphertext. According to the present disclosure, a data owner encrypts the generated sensitive data and the keywords extracted according to the data with his own key, and then sends the encrypted transaction information to the cloud server. The cloud server verifies the identity of the data owner. If the verification succeeds, the uploaded ciphertext data is stored on a local server, and a ciphertext index, keyword ciphertext and related evidences of the data storage are uploaded to an alliance chain. The alliance chain node verifies the consistency of the uploaded transaction information, and if the verification succeeds, the transaction information is recorded.

Abstract: A plant protein-based triboelectric nanogenerator (TENG), and a fabrication method and use thereof are provided. The TENG includes a triboelectric negative layer and a protein film, where the protein film and the triboelectric negative layer are stacked surface-to-surface; and an electrode is adhered to or plated on a back surface of each of the protein film and the triboelectric negative layer, or only a back surface of either of the protein film and the triboelectric negative layer is provided with a grounded electrode. A protein powder is dissolved in water or an ethanol aqueous solution, then a plasticizing agent is added, and the protein is denatured through thermal treatment to obtain an extended structure required for film formation; and the solvent is evaporated, and a resulting product is dried to obtain the protein film with uniform texture and excellent transparency and flexibility. The TENG is used in crop growth.

Abstract: The present disclosure discloses a self-packing three-arm thermal scanning probe for micro-nano manufacturing, comprising: a three-arm cantilever beam, metal contact pads, a nichrome heating electrode for printing, a nichrome heating electrode for transportation, and a polymer storage area. The present disclosure is manufactured by conventional micro-nano machining processes such as lithography and wet etching. In the present disclosure, a gradient density design of heating electrodes is used to generated continuous change of temperature gradients, thus realizing continuous transportation of a printing material from a storage area to a tip area, which realizes self-packing.

Abstract: The present invention discloses a sludge anaerobic fermentation treatment method with simultaneously enhanced acid production and phosphorus removal. The method includes steps of: (1) adding waste activated sludge into an anaerobic reaction system, with a concentration of a total suspended solid (TSS) of 10000-15000 mg/L; (2) maintaining a pH value of the waste activated sludge at 10±0.1; adding powdery magnetite of 0.3-0.9 g/gVS S. Compared with simple alkaline conditions, in the method of the present invention, an accumulation amount of short chain fatty acids (SCFAs) in a fermentation broth is increased by 20%, and a content of orthophosphoric acid is reduced by 10%. The method can further improve the enhancing effect by using sulfuric acid to modify the magnetite, the accumulation amount of SCFAs can be increased by 36.7% at most, and the content of phosphorus and refractory organic substances can be reduced by 32.4% and 40.4% at most, respectively.

Abstract: The present invention discloses a high step-down modular DC power supply, belonging to the field of power electronics technology, and the high step-down modular DC power supply includes an upper modular cascade circuit string, a lower modular cascade circuit string, a load, and an input source, where the upper modular cascade circuit string includes i upper sub-module circuits, and the lower modular cascade circuit string includes j lower sub-module circuits. A combination manner of module circuits includes: upper module string cascading, lower module string cascading, and hybrid cascading of the upper module string and the lower module string. The power supply is formed to be a high voltage step-down ratio power supply with high voltage direct current input and low voltage direct current output through modular cascading.

Abstract: Provided is a globally optimal robot visual positioning method and device based on point-line features. The method comprises the following steps: acquiring a priori three-dimensional map of a current scene constructed in advance; acquiring a current image of the robot and the inertial measurement data; calculating a pitch angle and a roll angle of the current robot pose according to the current inertial sensor data and the inertial sensor data in the priori map; matching the two-dimensional point-line features detected in the current image with three-dimensional point-line features in a priori map; separating the rotation and translation of the pose to be solved according to the matched feature pairs, solving the rotation and then solving the translation so as to complete the dimensionality reduction of the search space.

Abstract: The present disclosure provides a circuit and method for expanding the lock range of injection-locked oscillators. The circuit includes N injection-locked oscillators and a lock detector, where the lock detector includes an alignment monitor, a clock selector, and N self-samplers. A pulse reference signal is inputted into the N injection-locked oscillators, and the output of each injection-locked oscillator is connected to the clock selector and the corresponding self-sampler. The self-samplers sample the outputs of the N injection-locked oscillators and output the sampling results to the alignment monitor. The alignment monitor monitors the sampling results, determines the locking conditions of the injection-locked oscillators, and turns off the unlocked oscillators. The clock selector selects a locked oscillator and transmits the output of the locked oscillator as a system lock.

Abstract: A phase frequency detector-based high-precision feedback frequency measurement apparatus and method: a Field Programmable Gate Array (FGPA) roughly measures a frequency fx of a measured time-frequency pulse by an equal-precision frequency measurement method; a Direct Digital Synthesizer (DDS) automatically synthesizes a frequency fx? according to the fx roughly measured by the FPGA; the fx and the fx? are sent to a phase frequency detector for performing phase frequency detection and then sent to the FPGA after passing through a charge pump, a low-pass filter circuit, and an (Analogue-to-Digital) A/D converter; the FPGA processes a frequency difference obtained by the phase frequency detector and then transmits the processed frequency difference to the DDS to form a negative feedback frequency measurement system so that the DDS continuously adjusts the fx? according to a frequency difference measurement result until the output of the DDS is stable.

Abstract: The invention proposed a space vector pulse width modulation (SVPWM) method for any level cascaded H-bridge inverter. The multilevel space vector diagram is re-divided, and the coordinates of the nearest three vectors (NTVs) are directly obtained by judging the position of the reference vector. The duty cycles of the NTVs is calculated through additional vector which is equivalent to the reference vector. Then, the switching states are obtained by zero-sequence component and coordinate transformation, and the desired reference vector is synthesized for the SVPWM modulation. The invention realizes multilevel modulation in Cartesian coordinates without any iterative calculation, and the calculation is independent of the level number. Furthermore, the locating of the reference vector and the calculation of the duty cycles are simplified, and the calculation complexity is reduced.

Abstract: A sample to be measured is placed in a medium solution between two circular magnets to ensure that the sample to be measured is levitated in a set circular area between the two circular magnets, and a levitation position of the sample to be measured in the magnetic field is measured. The density of the sample is calculated according to formula (I): ? s = ? m + ? m - ? s g ? ? 0 ? ( B r ? ? B z ? r + B z ? ? B z ? z ) . Compared to the prior art, the method of the present disclosure provides a novel method for measuring a density of a substance, in which the involved device is easy to operate and has low cost, and the measurement results are easy to observe and have high accuracy.

Abstract: A patrol helmet and method for livestock and poultry farms is described herein. The patrol helmet is wirelessly connected to an online farm management system on a cloud platform. The patrol helmet includes a helmet body, a controller, an augmented reality (AR) display component, an infrared (IR) camera, and a visible light camera. The AR display component is secured at the bottom edge of the helmet body. Both the IR camera and the visible light camera are disposed on the helmet body. The IR camera, the visible light camera, and the AR display component each is electrically connected to the controller. The IR camera and the visible light camera are configured to photograph livestock or poultry in an area in front of a wearer to obtain a temperature and an image of the livestock or the poultry.

Abstract: An optimization method for capturing proteins by multi-column continuous chromatography (MCC), including the following steps: step 1, under the conditions of a set loading protein concentration and an arbitrary load residence time, performing a single time of protein breakthrough experiment to obtain a protein breakthrough curve; step 2, under a set breakthrough percentage for a target protein, integrating the breakthrough curve to obtain a single-column loading capacity and establishing a linear relationship between the interconnected load time and the load residence time; step 3, solving for the optimal number of operating columns for capturing proteins by MCC based on step 2; step 4, solving for the optimal load residence time for capturing proteins by MCC based on step 2, step 3; and step 5, solving for the maximum productivity of capturing proteins by MCC based on step 4.

Abstract: A tracer particle spreading device for a boundary layer flow visualization experiment based on a flat plate includes a tracer particle generator, a smoke storage box, and a wall-surface particle distribution box. Fume and oil are pressurized by a micro pump and flows into a heating pipe to be heated and vaporized, and then is ejected from a nozzle to form tracer particles. The tracer particles enter the smoke storage box via a smoke guiding tube. An axial flow fan is mounted on a wall surface of the smoke storage box. The tracer particles enter a cavity of the wall-surface particle distribution box via the smoke guiding tube, and the tracer particles are rectified by a rectifying plate and ejected from a spreading slit. An outlet of the spreading slit is at an angle of 15° with respect to an experiment flat plate.

Abstract: Provided is a supergravity directional solidification melting furnace equipment, including a supergravity test chamber and, mounted in the supergravity test chamber, a high-temperature heating subsystem, a crucible, and an air-cooling system. The supergravity test chamber is mounted with a wiring electrode and a cooling air valve device. The high-temperature heating subsystem is fixed in the supergravity test chamber. The crucible and the air cooling system are provided in the high-temperature heating subsystem. The high-temperature heating subsystem includes upper, middle, and lower furnaces, a mullite insulating layer, upper and lower heating cavity outer bodies, upper and lower heating furnace pipes, and a crucible support base. A high-temperature heating cavity is divided into upper and lower parts, is provided therein with a spiral groove, and is fitted with a heating element. The crucible support base is provided therein with a vent pipe channel into which a cooling air is introduced.