Abstract: A screw pair including inner walls of screw holes in a working nut and a pre-tightening nut with sensor groups including a plurality of displacement sensors capable of measuring a value of a gap between an inner and outer wall of a screw in a diameter direction of the screw hole, the group includes four displacement sensors evenly distributed in a circumferential direction of the screw hole, every two displacement sensors are paired and symmetrical about a center axis, and projections of a plurality of sensor groups in an axial direction overlap the screw; and an adaptive excitation coil is mounted to each displacement sensor, which is capable of attracting the screw in a measurement direction of the adaptive displacement sensor, and a magnetic force of the coil attached is adjustable to change the value of the gap, so that axes of the screw, working nut, and pre-tightening nut coincide.

Abstract: A large-load unmanned aerial vehicle (UAV) for plant protection with adjustable spraying swath and pesticide application amount is provided, relating to the technical field of pesticide application of unmanned aerial vehicles. The large-load unmanned aerial vehicle for plant protection comprises a large-load unmanned aerial vehicle, a pesticide box, a variable pesticide application system, and adjustable spraying swath mechanisms, wherein the pesticide box is fixed to landing gears of the unmanned aerial vehicle and is positioned below a control platform of the unmanned aerial vehicle; the adjustable spraying swath mechanisms are arranged on the landing gears, the variable pesticide application system is connected with the pesticide box and the adjustable spraying swath mechanisms, the variable pesticide application system and the adjustable spraying swath mechanisms are electrically connected with the control platform, and the control platform is in communication connection with a remote control handle.

Abstract: Provided is a steam jet multifunctional aircraft deicing vehicle with steam jet, includes a vehicle body, where a steam generating assembly is arranged in the vehicle body, and the steam generating assembly is connected with a steam conveying assembly. A moving assembly is rotatably connected above the vehicle body, and the moving assembly is rotatably connected with an execution assembly. The execution assembly includes a first spray head assembly and a second spray head assembly. The steam conveying assembly includes a first supercharger and a second supercharger arranged side by side, where an air outlet end of the first supercharger is communicated with one end of a first air outlet pipe, and an other end of the first air outlet pipe is communicated with spray heads of the second spray head assembly through a first air pipeline.

Abstract: A wall-climbing robot system and method for rapid nondestructive inspection of hidden defects in culverts and sluices. The system includes: a robot vehicle body; navigation positioning system and moving system, both mounted on the robot vehicle body; automatic knock inspection system, mounted at the vehicle body front end; mobile ultrasonic rapid inspection system and corrosion inspection system, dual-power system, formed by a non-contact negative pressure adsorption apparatus and rotor booster apparatuses, the non-contact negative pressure adsorption apparatus mounted on the vehicle body bottom, the rotor booster apparatuses mounted on two sides of the vehicle body; and a master controller, communicating with the navigation positioning system, moving system, automatic knock inspection system, mobile ultrasonic rapid inspection system, corrosion inspection system, and dual-power system.

Abstract: A model predictive virtual synchronous generator inverter control method considering a frequency-movement direction includes: obtaining a current frequency absolute value based on fundamental frequency of an inverter and a steady-state absolute value based on the fundamental frequency of the inverter; determining a frequency-movement state by comparing the above two absolute values: in a state of deviating from the fundamental frequency or a state of regressing to the fundamental frequency; setting a corresponding prediction output horizon according to the frequency-movement state, and constructing a cost function considering the frequency-movement state; and calculating an optimal virtual power increment value based on the cost function, then calculating an optimal virtual power, inputting the optimal virtual power to a swing equation of a virtual synchronous generator, and performing frequency adjustment according to an output value.

Abstract: A power flow calculation and AC/DC hybrid power flow calculation method for a flexible DC transmission system, the method including: according to the flexible DC transmission system under different control strategies, constructing a unified power flow model with a unified structure; determining a current main converter station, a current control strategy and an initial value and a limit value thereof, and forming the power balance equations under the current control strategy according to the unified power flow model; updating the current DC node voltage according to the voltage variation obtained by solving the power balance equations, and, if the updated DC node voltage exceeds the limit value, switching the control strategy; and if the updated DC node voltage does not exceed the limit value and the iteration constraints are not satisfied, alternating the main converter station according to the priority until iteration is completed.

Abstract: Embodiments of the present disclosure relate to automated validation of medical data. Some embodiments of the present disclosure provide a method for medical data validation. The method comprises obtaining target medical data generated in a medical test and obtaining a machine learning model for validating medical data. The machine learning model represents an association between the medical data and validation results, the validation results indicating information about predetermined actions to be performed on the medical data. The method further comprises determining a target validation result for the target medical data by applying the target medical data to the machine learning model, the target validation result indicating information about a target action selected from the predetermined actions to be performed on the target medical data. Through the solution, it is possible to achieve automated medical data validation with high accuracy and efficiency as well as reduced manual efforts.

Abstract: An alumina-based ceramic tool material with low thermal expansion and a preparation process thereof, accordingly, the ceramic tool material may have both the high hardness of alumina ceramics after the hot pressing sintering, and reduces the thermal expansion coefficient of the overall ceramic material by adding the Sc2W3O12 as the negative thermal expansion phase, which improves the thermal shock resistance of ceramic tools in high-speed cutting engineering and meets the requirements of large temperature range during the machining of nickel-based superalloys. Moreover, the composite material does not use metal binder and has strong thermal stability even in the high-speed machining under extreme heat-force-chemistry coupling, so it has a high machining compatibility for nickel-based superalloys.

Abstract: An impact-resistant balanced hydro-cylinder with pressure relief and buffering protection comprises a cylinder body (11), a piston (13), a piston rod (14), and a first valve core (21) and a second valve core (51) slidable relative to the cylinder body (11). A closed first gas cavity (22) and a closed second gas cavity (52) are respectively formed between the two valve cores and inner walls of two opposite ends of the cylinder body (11). A closed first oil cavity (32) and a closed second oil cavity (42) are respectively formed between the two valve cores and two end faces of the piston (13). A through hole (33) for the first oil cavity and a through hole (43) for the second oil cavity are respectively provided in the positions on the cylinder body (11) corresponding to the first oil cavity (32) and the second oil cavity (42).

Abstract: A hydraulic actuator with no friction and zero leakage and its drive system are provided. The hydraulic actuator includes a thickened disc structure A and a thickened disc structure B. The second end face of the thickened disc structure A is connected with the first end face of the thickened disc structure B, and a control cavity is formed between the second end face of the thickened disc structure A and the first end face of the thickened disc structure B. The drive oil access hole is arranged on the thickened disc structure B, and the control cavity is connected with the drive oil access hole. The displacement output method based on elastic deformation is adopted, which completely avoids the nonlinear phenomena such as leakage and friction, and reduces the difficulty of high-precision control of the actuator.

Abstract: The present disclosure provides a grouting and water-plugging device for a fractured rock in a mine coupling state and a test method, and relates to the technical field of rock mechanics testing. The device includes a pressurizer, a reservoir, a test box, and a grouting pump. The reservoir includes a temperature sensor and a pressing-water plate. The pressing-water plate is connected to the pressurizer through a pressurizing rod. A pressure measuring pipe and a drainage pipe are installed on an outer side of the reservoir. The reservoir is connected to a water pump through a water injection pipe. The test box includes a rock, a transverse force exerting plate, a longitudinal force exerting plate, a stress sensor and the temperature sensor. The longitudinal force exerting plate is provided with multiple water through holes. A sliding box door is hinged to a front wall of the test box. The pressure measuring pipe and the drainage pipe are installed on a rear wall of the test box.

Abstract: The present disclosure discloses an abrasive water jet full-section cutting type cutter head and application devices. The cutter head includes a cutter head body and a rotor eccentrically arranged on a working surface of the cutter head body. The rotor revolves with the cutter head body and also rotates about its own axis. At least one first nozzle is arranged on an edge of a working surface of the rotor. At least one group of second nozzles and at least one third nozzle are arranged on the working surface of the cutter head body, and the second nozzles and the third nozzle cooperate during the rotation of the cutter head body and the rotor, then a material to be cut is cut into a plurality of concentric rings, and the first nozzle cuts off the ring material to form fragments.

Abstract: A preparation method of an expansive polymer grouting material for treating high-pressure large-flow-rate karst water inrush includes: 1) adding a crosslinking agent to acrylic acid; then adding a polymer water-absorbent resin comonomer and performing a polymerization reaction to obtain a precursor; 2) adding an initiator to the precursor obtained in step 1), heating the mixture, performing a reaction to obtain a hydrogel, and grinding the hydrogel to obtain a primary polymer water-absorbent resin; 3) spraying a surface crosslinking agent onto a surface of the primary polymer water-absorbent resin obtained in step 2), and drying the product; and 4) preparing a suspension from an inorganic water conducting agent, spraying the suspension onto the product obtained in step 3), and performing drying to obtain the expansive polymer grouting material.

Abstract: A method for judging freshness of cultured fish product based on eye image recognition is provided, which relates to the field of image processing and includes the following steps: obtaining eye area and eye center point of each cultured fish product; obtaining a first data category and a second data category of each gray scale change sequence according to each gray scale change sequence of each eye area; calculating a first mean value and a second mean value of each gray scale change sequence; obtaining the fish eye turbidity of each eye area according to the first mean value and the second mean value; obtaining the fish eye plumpness of each eye area according to the first data category and the second data category; and obtaining the freshness of each cultured fish product according to the fish eye turbidity and fish eye plumpness in each eye area.

Abstract: A wave detector integrated device includes a support, protective shell and mode converter. The protective shell is installed on the support and rotates by the mode converter, and has a hollow cylindrical structure. A seismic source hammer is suspended at a protective shell central axis position. Electromagnetic accelerators are installed in a bus direction of the protective shell, and the seismic source hammer is connected with the electromagnetic accelerators. A drill bit type wireless transmission wave detector or standby flat bottom type wave detector is connected above the protective shell through a second telescopic rod having a driving device therein and driving the drill bit type wave detector to rotate. A power supply is installed inside the protective shell, and is connected with a current controller and circuit protection device. The current controller is respectively connected with the electromagnetic accelerators, drill bit type wave detector, driving device and mode converter.

Abstract: A preparation process of atomically precise nine-nuclear silver nanoclusters (Ag9-NCs) fluorescent nanotube and its application in the detection of arginine (Arg), the fluorescent nanotube is formed by supramolecular self-assembly of Ag9-NCs and peptide (DD-5); the fluorescent nanotube prepared by the present invention has good luminescence performance due to its highly ordered structure, the quantum yield is 8.11%, and the fluorescence lifetime is 6.10 ?s; after adding Arg, the highly ordered structure is destroyed, resulting in fluorescent quenching; the preparation method of the Ag9-NCs fluorescent nanotube of this invention is simple, the cost is low; at the same time, the detection method is fast and easy to observe.

Abstract: The present disclosure relates to a hydraulic support with a quick response function for coal wall spalling, which includes a base, an upright post, a top beam, an extensible canopy, a face guard, and a vibration meter. The vibration meter is mounted on a hydraulic support, and detects a vibration signal of a coal wall in a non-contact mode. The face guard includes a primary face guard, a secondary face guard, and a tertiary face guard connected in sequence. One side, close to a coal wall, of the primary face guard is connected to a quick response device. The quick response device is in signal communication with the vibration meter. After receiving the vibration signal of the coal wall, the quick response device is abutted against the coal wall before the secondary face guard and the tertiary face guard fit the coal wall.

Abstract: A heat flux sensor, comprising: a ceramic heat sink; a sensitive element made of a single-crystal material and fixed to the ceramic heat sink through a thermally conductive and electrically insulative adhesive; a heat absorption layer arranged on an upper surface of the sensitive element; a first metal electrode and a second metal electrode arranged on the upper surface of the sensitive element; a third metal electrode arranged on the upper surface of the sensitive element; a fourth metal electrode arranged on a lower surface of the sensitive element; and a fifth metal electrode arranged on an upper surface of the ceramic heat sink; wherein a voltage signal between the first metal electrode and the second metal element is a transverse voltage Ux, and a voltage signal between the third metal electrode and the fourth metal electrode is a longitudinal voltage Uz.

Abstract: Disclosed are a compound impact-resistant device and an application thereof. The compound impact-resistant device includes an inner cylinder, a first pressure sensor and an outer cylinder; an inner cavity of the inner cylinder is connected to a magnetorheological damper, a spiral valve element, a floating piston and a spring from bottom to top; and the outer cylinder is connected to a piston rod, a bottom end of the piston rod penetrates a top of the inner cylinder, the spring and the floating piston to be connected to the spiral valve element, and a portion below the spiral valve element is filled with hydraulic oil. The compound impact-resistant device can provide specific initial support force and achieve active self-adaptation to dynamic impact, thus solving the problems that traditional hydraulic buffers cannot provide initial support force and traditional mechanical crushing members have difficulty in providing large support force.

Abstract: A TBM-mounted surrounding rock wear resistance testing system and method, the system including: a fixing module, arranged on a TBM, the module has a movable end for extending to the surrounding rock of a tunnel; a surrounding rock polishing module on the movable end, the module includes a polishing mechanism for test area; a surrounding rock wear resistance testing module on the movable end, follows the movable end moving the test area, and including a mechanism for testing the wear resistance of the polished test area and a drive mechanism thereof; and a central control module, configured to control the motion states and operations of the fixing module, the surrounding rock polishing module and surrounding rock wear resistance testing module, and determine the wear resistance of the surrounding rock according to the wear resistance test result. The system can polish tunnel surrounding rock during TBM excavation and test wear resistance.