Abstract: A planetary gear actuator including a sun gear, a rotary internal gear being concentric with the sun gear, a fixed internal gear being concentric with the sun gear, compound planetary gears, and a carrier connected to each of the compound planetary gears so as to be rotatable relative to each of compound planetary gears may be provided, Each of the compound planetary gears may include a first planet gear engaged with the sun gear, a second planet gear at one side of the first planet gear, engaged with the rotary internal gear, and having a smaller number of teeth than the first planet gear, and a third planet gear at another side of the first planet gear, engaged with the fixed internal gear, and having a smaller number of teeth than the first planet gear. One compound planetary gear may overlap another compound planetary gear in a thickness direction.

Abstract: The present invention provides a method for forming a history of natural gas accumulation by using carbon isotopes by a pyrolysis experiment. The method includes: obtaining activation energy distribution and a frequency factor of light carbon methane; carrying out carbon isotope kinetics simulation of natural gas in a study area by using a spreadsheet function of Excel to obtain activation energy, a mass fraction and a frequency factor of heavy carbon methane; establishing a burial history and a thermal history of the study area based on geological data; and combining the activation energy distribution and frequency factor of the heavy carbon methane with the burial history and thermal history of the study area, and establishing an instantaneous curve, a cumulative curve and a stage cumulative curve of natural gas under geological conditions on a geologic time scale.

Abstract: A multi-arm robot for realizing conversion between sitting and lying posture of patients and carrying patients to different positions is disclosed. The complete robot includes a manipulator module, a trunk module, a chassis moving module and a control module. The manipulator module comprises at least three manipulators, which are connected with the trunk module by linear modules. The trunk module comprises a trunk body and four linear modules, which are connected with the chassis moving module by bolts. The chassis moving module comprises a plurality of omnidirectional wheels and a telescopic counterweight. The control module includes an actuator module, an operation module, an information acquisition module, a motion control module, a data processing module, a communication module and an early warning module.

Abstract: A binary neural network model training method and system includes constructing an online distillation-enhanced binary neural network training framework, wherein a teacher network in the online distillation-enhanced binary neural network training framework is an initial real-valued neural network model and an initial assistant neural network model, and a student network is an initial binary neural network model; and training the three network models using an online distillation method to improve the performance of a binary neural network. In addition, the binary neural network model is used for performing image classification on an image to be processed to improve the accuracy of the image classification.

Abstract: A separation and purification coupled process with a high helium yield and diversified products is provided. The process is as follows. Firstly, a low-concentration helium-containing gas after being pressurized and pre-treated enters a two-stage and two-section membrane separation unit to produce a helium product with a medium concentration by concentrating stage by stage through the membrane separation unit. A part of the helium with medium concentration enters an adsorption unit for further concentration to produce a helium product above grade A.

Abstract: Disclosed are a device and a method for measuring a fretting displacement in a power cycling of a press-pack insulated gate bipolar transistor (IGBT). The IGBT includes: a bracket; slide bars slidably mounted on the bracket and are arranged at least four along a circumferential direction of the bracket; sensors respectively slidably installed on the bracket and the slide bars; and a power cycling experiment device arranged inside the bracket.

Abstract: A real-time pose measurement method of a planar coding target for a vision system. The planar coding target includes a plurality of coding elements, a coding block, a coding template, a minimum identification unit pattern and a coding pattern. Each coding element has a unique coding value, and serial numbers of the coding elements are different from each other. The coding block includes four coding elements that are distributed in the same rectangle ABCD and do not overlap with each other. A center of the coding block is an intersection point O of two diagonals of the rectangle ABCD. A coding value of the coding block is associated with coding values of the four coding elements contained therein.

Abstract: Disclosed is a pressure balancing clamp for a press-pack insulated gate bipolar transistor (IGBT) module. The pressure balancing clamp for a press-pack IGBT module includes a bracket, where the bracket is provided with two longitudinally arranged pressure equalizing plates in a sliding way; the pressure equalizing plates are connected through pressure sensors; the upper and lower ends inside the bracket are respectively connected with the pressure equalizing plates through hydraulic devices and a displacement compensation device; opposite surfaces of the two pressure equalizing plates are respectively provided with heat dissipation and confluence devices. The pressure sensors are in one-to-one correspondence with the hydraulic devices and are electrically connected. The hydraulic devices adjust the pressure according to the readings of the pressure sensors in corresponding directions, so that the pressure of the press-pack IGBT module is balanced.

Abstract: A processing die and a preparation method for a fastener are provided. The processing die includes a punch and a die. The top of the punch and the bottom of the die are configured for being connected with a hydraulic press, the die includes a first half die and a second half die which are clamped to form an inlet channel, an expansion corner channel and a torsion channel, and an extrusion channel is included in the forming sliding block, the inlet channel, the expansion corner channel, the torsion channel and the extrusion channel are sequentially assembled to form a die channel cavity, and a billet to be processed is successively subjected to upsetting, shearing, torsion and extrusion in a single die under the pressure of the punch.

Abstract: An apparatus and a method for controlling motion of a vehicle to improve turning motion performance are provided. The processor determines a riding position of a user, receives information about a steering angle of the vehicle, and outputs a vehicle control signal with regard to turning motion performance according to at least one of a phase difference between a yaw rate and lateral acceleration or a lateral slip angle with respect to the riding position, based on the received steering angle. A controller controls the vehicle in accordance with the vehicle control signal. The apparatus provides a passenger of the vehicle with optimal turning motion performance.

Abstract: The invention provides a method for sequence controllable block copolymerization of a cyclic ester monomer and an epoxy monomer, including: in an inert atmosphere, adding the epoxy monomer and/or the cyclic ester monomer into a catalytic initiating system including an organic base and an alkyl borane for reaction, so as to obtain a sequence controllable polyether-polyester block copolymer of the cyclic ester monomer and the epoxy monomer, i.e. a polyester-b-polyether or a polyether-b-polyester. The invention can prepare various polyether-polyester block copolymers of which the molecular weights, block sequences, block ratios and pendant group combinations can be flexibly adjusted. The invention provides a method for continuously preparing an aliphatic polyester-polyether block copolymer by a one-pot method utilizing a catalytic system of a metal-free Lewis acid-base pair.

Abstract: A pressure measuring device for a scale model for elastic similar structure of a wing in a large transport plane adopts a bracket for pressure measuring steel pipes formed by 3D printing, shapes of an upper surface and an lower surface of the bracket are completely the same as local airfoile profiles of a skin at required pressure measuring positions, and the upper surface and the lower surface of the bracket are bonded to the skin and wing beams; a pressure measuring hose is connected with the pressure measuring steel pipe, and the pressure measuring steel pipe is embedded into the bracket and fixed to it; the upper surface and the lower surface of the bracket are provided with semi-cylindrical convex structures; and the pressure measuring steel pipe extends out of the pressure measuring hole in the surface of the skin for pressure measuring steel pipe in the bracket.

Abstract: A dynamic optimization method for procurement specifications of BEF raw materials includes: obtaining finished product data; obtaining an initial feasible raw material size set; mapping the initial feasible raw material size set in length and width directions to obtain a complete feasible raw material size set; filtering an unreasonable raw material size out of the complete feasible raw material size set to obtain a final feasible raw material size set; and determining whether a scale of the final feasible raw material size set is larger than a threshold, if not, building and solving an integer programming model, and outputting results; and if yes, batchwise processing the final feasible raw material size set to obtain multiple subsets, and building an integer programming model for each subset, and solving the integer programming model, and outputting results. A dynamic optimization system of BEF is further provided.

Abstract: The present invention belongs to the technical field of petroleum exploitation engineering, and discloses a 3D modeling method for cementing hydrate sediment based on a CT image. Indoor remolding rock cores or in situ site rock cores without hydrate can be scanned by CT; a sediment matrix image stack and a pore image stack are obtained by gray threshold segmentation; then, a series of cementing hydrate image stacks with different saturations are constructed through image morphological processing of the sediment matrix image stack such as dilation, erosion and image subtraction operation; and a series of digital rock core image stacks of the cementing hydrate sediment with different saturations are formed through image subtraction operation and splicing operation to provide a relatively real 3D model for the numerical simulation work of the basic physical properties of a reservoir of natural gas hydrate.

Abstract: A boss structure sealing experiment device for an IV type hydrogen storage cylinder. The device includes a high-pressure chamber, a sealing leakage structure, a cylinder mouth valve, and a low-pressure chamber, where the high-pressure chamber, the sealing leakage structure, and the low-pressure chamber are tightly connected to one another through flange bolts, and the cylinder mouth valve is tightly connected to the high-pressure chamber through threads. Further disclosed is a sealing experiment system. The system includes a boss structure sealing experiment device, a high-pressure gas supply device, and a leaked gas detection device. The high-pressure gas supply device consists of a hydrogen source, a compressor, a buffer tank, a valve, and a pressure gauge; and the leaked gas detection device consists of a gas mixing chamber, a carrier gas, and a gas leakage detector. Further disclosed is a test method for a boss structure sealing experiment.

Abstract: A speed control method for a permanent magnet synchronous motor considering current saturation and disturbance suppression aims to effectively ensure that a current of the motor is always within a given range to avoid the problem of control performance reduction caused by the fact that the current gets into a saturation state, ensure the safety of a system, do not need to use unavailable state variables such as motor acceleration and the like, effectively estimate and compensate disturbances including parameters uncertainty and unknown load torque disturbance existing in a permanent magnet synchronous motor system, and rapidly and accurately control a speed of the motor finally. There is no need to configure a plurality of sensors in practical industrial application, so system building costs can be reduced on the one hand, and the stability of the system can be improved on the other hand.

Abstract: The present invention discloses a lignin-based hierarchical porous carbon with high specific surface area and preparation method and application thereof. The present invention employs maleic anhydride, acrylic acid, and hypophosphorous acid to modify a lignin, then performs a cross-linking reaction with a glutaraldehyde-triethanolamine condensate to prepare a lignin graft-copolymerized by phosphino carboxylic acid copolymer, and then dropwise adding a soluble calcium salt solution and a soluble carbonate solution into the lignin graft-copolymerized by phosphino carboxylic acid copolymer dispersion successively, co-precipitates to prepare a lignin/nano CaCO3 complex, finally obtains a lignin-based hierarchical porous carbon with high specific surface area through carbonizing at a high temperature.

Abstract: The present disclosure provides a carbide blade grinding forming processing production line, relates to the field of blade processing in forming, and provides a production line for grinding forming processing of a carbide blade with inscribed circular holes, which has functions of blade grinding forming processing, blade cleaning and drying and detection of external dimension of a formed blade, and has an automatic loading and uninstalling function. In most processing course of the blade, the cutter head is taken as a carrier, and an overturning device is configured to overturn a whole cutter die box, such that integral end surface overturning of the cutter head in the cutter die box after single end surface grinding is realized, and blade filling processes in different processing links are reduced.

Abstract: A toolholder matched with the internal jet cooling spindle for cryogenic coolant is mainly composed of a hollow toolholder body, a high-performance thermal insulation structure and a bidirectional sealing structure. They can guide the cryogenic coolant from the spindle to the internal cooling channel of cutting tool and realize the cryogenic thermal insulation and dynamic sealing. The high-performance thermal insulation structure inside the toolholder employs the material with a low thermal conductivity and a low linear expansion coefficient to restrain the low temperature impact of cryogenic coolant on the toolholder and spindle, to ensure the dimensional accuracy and assembly accuracy of the toolholder. The bidirectional sealing structure in the toolholder uses the ultra-low temperature resistant seal rings to prevent the cryogenic coolant from leaking towards the spindle and the cutting tool, to ensure the stability of the coolant transport.

Abstract: Disclosed is a transient-state THz spectrometer applied to cells and biological macromolecules, including a femtosecond laser amplifier. A femtosecond laser output by the femtosecond laser amplifier is divided into two beams of pump light and probe light after passing through a beam splitter of which a transmission-reflection ratio is 7:3, the pump light is focused to irradiate a gap between electrodes of a nonlinear photoconductive antenna and emit a terahertz wave after successively passing through a half wave plate, a silver-plated reflector and a first lens, the terahertz wave forms a terahertz wave collineation after successively passing through a second lens, a slab waveguide, a third lens and an ITO film, the terahertz wave collineation and the probe light form a probe light collineation of wavefront tilt which is perpendicularly incident on a ZnTe crystal and detected and recorded by using a CCD camera.