Abstract: A cutting stock method for a rectangular sheet with defects includes: acquiring information of the rectangular defective sheet, including dimension information of the rectangular sheet and target blocks, and location information of the defects; acquiring a cutting position discrete set of the rectangular sheet; cutting the rectangular sheet according to the cutting position discrete set into a plurality of target blocks; calculating a sum of values of the target blocks, and selecting an optimal cutting solution with the largest sum of values; and cutting the rectangular sheet according to the optimal cutting solution.

Abstract: A method for constructing a porous micro-nano structure, includes: thoroughly mixing glass powders and metal powders to obtain a mixture; coating the mixture on a surface of a substrate, and forming a coating on the surface, wherein a temperature of forming the coating and a melting point of the glass powders comply with the following formula: Tforming?Tglass?50° C.; and constructing a surface structure of the coating to obtain a porous micro-nano structure coating on the surface, such that a material with a porous micro-nano structure is obtained. The method is simple and has a low cost. The porous micro-nano structure coating prepared has excellent mechanical stability.

Abstract: A method for constructing a porous micro-nano structure, includes: thoroughly mixing glass powders and metal powders to obtain a mixture; coating the mixture on a surface of a substrate, and forming a coating on the surface, wherein a temperature of forming the coating and a melting point of the glass powders comply with the following formula: Tforming?Tglass?50° C.; and constructing a surface structure of the coating to obtain a porous micro-nano structure coating on the surface, such that a material with a porous micro-nano structure is obtained. The method is simple and has a low cost. The porous micro-nano structure coating prepared has excellent mechanical stability.

Abstract: A method for integrally forming a graphene film (GF) of a high specific surface area (SSA) by ultrafast ultraviolet (UV) laser processing, includes: selecting a carbon precursor material, where the carbon precursor material is one selected from the group consisting of a biomass/hydrogel composite and a heavy hydrocarbon compound; adding an activator solution to an inside of the carbon precursor material to obtain a composite with an activator uniformly loaded, and spreading the composite on a flexible substrate to form a carbon precursor material layer; heating and drying the carbon precursor material layer; in-situ processing with an ultrafast UV laser to obtain an activated GF of a high SSA; and cleaning and drying the activated GF. With the method of the present disclosure, a microporous activated GF of a high SSA can be directly processed in-situ on a flexible substrate.

Abstract: The present disclosure discloses a terahertz detector based on a Schottky contact grating structure. THz response frequency points are adjusted by adjusting parameters (a grating width, a grating length, a grating region area, a grating period, and a grating pattern form) of the Schottky contact grating structure (in the detector design stage, the grating structure parameters can be adjusted according to the actually required detection frequency points (single frequency point or multiple frequency points)), thereby realizing single-frequency detection or realizing that one detector supports the detection of multiple frequency points. The grating is introduced into the Schottky Barrier Diode, so that the grated Schottky contact resonates with the terahertz waves, the plasma resonance effect is enhanced, and the detection sensitivity is further improved.

Abstract: A three-dimensional measurement method comprises: converting a total number of levels of sawtooth fringes into a Gray code and acquiring a sawtooth slope coefficient; fusing the coefficient into a sawtooth fringe image to generate a target sawtooth fringe pattern; projecting each target sawtooth fringe pattern to a surface of a to-be-measured object through a projector, and collecting a deformed target sawtooth fringe pattern on the surface through a camera; solving a Gray code of each sawtooth fringe collection pattern at each pixel point according to a differential property of adjacent pixels in each sawtooth fringe collection pattern and solving a fringe level and a wrapped phase at each pixel point; calculating an absolute phase at each pixel point according to the fringe level and the wrapped phase at each pixel point, and reconstructing a three-dimensional point cloud through triangulation ranging to obtain a three-dimensional model of the to-be-measured object.

Abstract: A packing method for a defective sheet based on branch-and-cut algorithm, including: acquiring sheet information, where the sheet information includes size information of the defect sheet, size information of a target block and position information of a defect; based on actual cutting requirements, establishing constraints; and establishing a primal problem model according to the constraints; converting the primal problem model into a relaxed problem model; checking and verifying the obtained solution by x-check method to determine whether the obtained solution meets the constraints of the primal problem model; outputting the optimal solution to obtain an optimal cutting plan that meets the actual cutting requirements; and cutting the defective sheet according to the optimal cutting plan. A system for implement the packing method is also provided.

Abstract: A method for integrally forming a graphene film (GF) of a high specific surface area (SSA) by ultrafast ultraviolet (UV) laser processing, includes: selecting a carbon precursor material, where the carbon precursor material is one selected from the group consisting of a biomass/hydrogel composite and a heavy hydrocarbon compound; adding an activator solution to an inside of the carbon precursor material to obtain a composite with an activator uniformly loaded, and spreading the composite on a flexible substrate to form a carbon precursor material layer; heating and drying the carbon precursor material layer; in-situ processing with an ultrafast UV laser to obtain an activated GF of a high SSA; and cleaning and drying the activated GF. With the method of the present disclosure, a microporous activated GF of a high SSA can be directly processed in-situ on a flexible substrate.

Abstract: A method for generating millimeter wave noise with a flat RF (radio frequency) spectrum includes the following steps. A noise optical signal with an optical spectrum in Gaussian shape is output by a first optical emission module. The noise optical signal is transmitted to an optical coupler. n beams of noise optical signals with optical spectra in Gaussian shape is output by a second optical emission module. The noise optical signals is transmitted to the optical coupler. The noise light generated by the first optical emission module and the second optical emission module is coupled to the optical coupler. The coupled optical signals is transmitted to a photodetector. The beat frequency is performed by the photodetector to realize mapping transformation from the optical spectra to the RF spectra. The flat millimeter wave noise is output.

Abstract: A non-coherent long range (LoRa) communication system based on multiple-input multiple-output (MIMO) technology, including a transmitter and a receiver. The transmitter is configured to transmit signals to the receiver, and the receiver is configured to receive and demodulate the signals. The transmitter includes a bit-symbol converter, a space-time mapper, and a plurality of transmitting antennas. The space-time mapper is configured to select a transmit antenna for the signal in each transmission time slot and transmit a base Chirp signal x0 and the modulating signal xm to the receiver in different time slots. The receiver includes a plurality of receiving antennas. The receiving antenna is configured to preprocess the signal to obtain a first cache matrix and a second cache matrix. After Hadamard product operation is performed on the first and second cache matrixes, operation results of the receiving antennas are accumulated and demodulated to output demodulated information bits.

Abstract: A compliant mechanical system for Mini/Micro chip mass transfer and packaging comprises a flexure-based continuous ejector pin mechanism including a drive support plate, a mounting base, first thorn die attach drive devices, second thorn die attach drive devices, first flexible hinges, second flexible hinges, and a pricking pin. The first thorn die attach drive devices and the second thorn die attach drive devices are mounted on the drive support plate. A drive end of the first thorn die attach drive device horizontally passes rightward through the first flexible hinge at a corresponding position; a drive end of the second thorn die attach drive device horizontally passes leftward through the first flexible hinge at a corresponding position; and the mounting base is hinged to the drive ends of the two thorn die attach drive devices through the second flexible hinges.

Abstract: The present application relates to an N×M terahertz detector array imaging system based on a multi-frequency antenna structure, wherein a single-frequency-point terahertz antenna used for receiving terahertz signals in a traditional detector is replaced with a multi-frequency-point terahertz antenna, thereby realizing that one detector supports the detection of multiple arbitrary different frequency points. The traditional detector needs to replace detectors with different frequency points for detection of different frequency points. The present application can design a multi-frequency-point terahertz antenna with arbitrary different frequency points according to actual needs, so that one detector can support the detection of multiple arbitrary different frequency points without the replacement of the terahertz detector, effectively reducing the cost of terahertz detection and imaging.

Abstract: A glucose sensor electrode, a preparation method therefor and the use thereof are provided for the rapid and sensitive detection of glucose. The method involves: (1) performing an alkali heat treatment to form a nanoneedle-structured titanium dioxide on the surface of a titanium electrode; (2) forming micro-region grooves on a nanoneedle-structured titanium dioxide film layer to obtain a nanoneedle-structured titanium dioxide having a micropattern; (3) depositing a chlorine-doped polypyrrole in the grooves by using chronopotentiometry; (4) forming a nanocone-structured citric-acid-doped polypyrrole on the chlorine-doped polypyrrole by using chronopotentiometry; and (5) grafting an enzyme capable of detecting glucose to obtain the glucose sensor electrode. This simple and stable process is low in cost, efficiently grafts the enzyme capable of detecting glucose on the surface of the electrode, and provides a stable electrode with higher reliability for detecting glucose.

Abstract: A method for a multi-UAV formation to pass through a frame-shaped obstacle, includes: obtaining in real time distance between the frame-shaped obstacle and the UAV formation and displacement of the UAV formation during a flight process; constructing a relative position model between the frame-shaped obstacle and the UAV formation; constructing a UAV velocity control model; constructing a parameter model based on the distance, the displacement, and the relative position model; constructing a position estimation model of the frame-shaped obstacle and a relative position estimation model among the UAVs based on the parameter model; and designing, based on the constructed position estimation model, the relative position estimation model, and the UAV velocity control model, a controller for the UAV formation to pass through the obstacle, and controlling a flight velocity of the UAV formation through the controller to enable the UAV formation to pass through the frame-shaped obstacle.

Abstract: Disclosed is a bias circuit for a radio frequency power amplifier, including a resistor voltage divider network, a power amplifier coupled with the resistor voltage divider network and a bias voltage adjusting loop coupled to the resistor voltage divider network and including one voltage divider resistor and one transistor pair; one terminal of the voltage divider resistor is connected with a reference voltage, and an other terminal is coupled with a gate of the first metal oxide semiconductor transistor; the transistor pair includes a first metal oxide semiconductor transistor and a second metal oxide semiconductor transistor, where a gate of the second metal oxide semiconductor transistor is coupled to the gate of the first metal oxide semiconductor transistor.

Abstract: A laser cutting method for irregular parts based on machine vision includes: (A) obtaining and numbering vertices of all parts on the layout diagram; (B) planning a part vertex set and an empty cutting path vertex set; (C) obtaining a shortest empty cutting path and the empty cutting path vertex set with the shortest empty cutting path; (D) cutting the parts one by one according to an order obtained by the CPLEX algorithm. This application further provides a laser cutting system.

Abstract: A compliant mechanical system for Mini/Micro chip mass transfer and packaging comprises a flexure-based continuous ejector pin mechanism including a drive support plate, a mounting base, first thorn die attach drive devices, second thorn die attach drive devices, first flexible hinges, second flexible hinges, and a pricking pin. The first thorn die attach drive devices and the second thorn die attach drive devices are mounted on the drive support plate. A drive end of the first thorn die attach drive device horizontally passes rightward through the first flexible hinge at a corresponding position; a drive end of the second thorn die attach drive device horizontally passes leftward through the first flexible hinge at a corresponding position; and the mounting base is hinged to the drive ends of the two thorn die attach drive devices through the second flexible hinges.

Abstract: A pilot protection method includes: obtaining time-domain signals data of target element at a preset sampling frequency; fusing time-domain signals data of multiple first sampling periods to obtain first time-domain signals combination data; based on a machine learning model, determining whether a fault occurs in target element according to the first time-domain signals combination data; when it is determined that a fault occurs in target element according to the first time-domain signals combination data, based on the machine learning model, determining whether a fault occurs in target element in the second sampling period according to the second time-domain signals combination data. The second sampling period is the sampling period after determining a fault occurs; when it is determined that the same type of fault occurs in target element in multiple consecutive second sampling periods, the pilot protection system is controlled to perform the protection action on the target element.

Abstract: A method of fabricating a magnetically-controlled graphene-based micro-/nano-motor includes: (a) mixing FeCl3 crystal powder with deionized water to obtain a FeCl3 solution; (b) completely immersing a carbon-based microsphere in the FeCl3 solution; transferring the carbon-based microsphere from the FeCl3 solution followed by heating to allow crystallization of FeCl3 on the surface of the carbon-based microsphere to obtain a FeCl3-carbon-based microsphere; (c) heating the FeCl3-carbon-based microsphere in a vacuum chamber until there is no moisture in the vacuum chamber; continuously removing gas in the vacuum chamber and introducing oxygen; and treating the FeCl3-carbon-based microsphere with a laser in an oxygen-enriched environment to obtain the magnetically controlled graphene-based micro-/nano-motor. A magnetically-controlled graphene-based micro-/nano-motor is further provided.

Abstract: A structured light 3D measurement device and method based on defocus-degree-based unwrapping. Binary fringes varying in fringe width are projected onto an object, and a corresponding fringe image is collected by a camera, and then subjected to phase demodulation to calculate a wrapped phase. The defocus degree is calculated according to modulation degrees of the binary fringes. The defocus degree is plugged into the defocusing phase function to obtain a normalized reference phase. The wrapped phase is subjected to phase unwrapping based on the normalized reference phase to obtain an absolute phase to reconstruct a 3D point cloud.