Abstract: A narrow pulse generation circuit used in a sequential equivalent sampling system. The circuit comprises a crystal oscillator, an edge sharpening circuit, an avalanche transistor single-tube amplifying circuit and a shaping network connected in sequence, wherein the edge sharpening circuit is used for carrying out edge sharpening on a square wave signal generated by the crystal oscillator; the avalanche transistor single-tube amplifying circuit is used for carrying out avalanche amplification on the sharpened square wave signal to generate a Gaussian pulse signal to adjust the amplitude of a pulse; and the RC shaping network is used for shaping the Gaussian pulse signal to adjust the pulse width at the bottom of the pulse to form a narrow pulse signal. The narrow pulse circuit has a simple structure and narrow pulse width at the bottom and facilitates increasing a signal-to-noise ratio of a whole sequential sampling system.

Abstract: A method for scaled-up synthesis of medium-entropy and high-entropy nanoparticles (NPs) including alloys and ceramics on various substrates such as carbon, metal and glass. The method requires only two steps to synthesize these NPs, including loading metal salt precursors with equal molar ratio onto a support and irradiating the support by highly intense laser pulses in liquid at ambient atmosphere. The method ensures multiple (3˜9) atoms to combine without segregation regardless of their mutual solubility. The method can easily tailor the particle size from nanometer to micrometer by controlling the parameters.

Abstract: The present disclosure relates to a road recognition method and system based on a seed point. The method includes: obtaining a remote sensing image; obtaining a grayscale image; inserting a seed point in the grayscale image; searching for four initial road boundary points using the seed point as a reference point; obtaining a smallest bounding rectangle search box formed by the four initial road boundary points; obtaining a plurality of candidate search boxes based on the obtained search boxes; determining whether a sum of squares of grayscale differences between the plurality of candidate search boxes and the obtained search box is greater than a preset threshold; and if yes, stopping searching and completing road recognition; or if not, selecting a new search box from the plurality of candidate search boxes, and retrieving a plurality of candidate search boxes based on the new search box.

Abstract: An adaptive steel structure cooling tower for resisting a severe typhoon includes a truss system, a hyperbolic enclosure plate system and a servo opening-closing system. The truss system includes a plurality of hoop trusses and a plurality of meridional trusses. The hyperbolic enclosure plate system includes a hyperbolic enclosure plate, a hyperbolic enclosure plate hoop bracket, a hyperbolic enclosure plate meridional bracket, a hyperbolic enclosure plate rotating pendant and a rotating motor. The servo opening-closing system includes a wind and rain sensor, and a controller. The hoop trusses and the meridional trusses are connected crisscross to form a force transfer structure of the whole steel structure cooling tower. The hyperbolic enclosure plate is mounted on the hoop truss, the servo opening-closing system is laid on the hoop truss, and a wind and rain sensor is installed on a hoop truss on the top of the tower body.

Abstract: Provided is a method for preparing a defect-free DDR molecular sieve membrane. Sigma-1 molecular sieve is used as an inducing seed crystal to prepare and obtain a continuous and compact DDR molecular sieve membrane on the surface of a porous ceramic support. An ozone atmosphere or an external field assisted technology is used to remove a template in the pores of the molecular sieve membrane at a low temperature. The invention avoids the formation of intercrystal defects and cracks, an activated DDR molecular sieve membrane has a good selectivity for separating CO2, and the membrane preparation time is significantly reduced.

Abstract: A method for enhancing the performance of pentacene organic field-effect transistor (OFET) using n-type semiconductor interlayer: an n-type semiconductor thin film was set between the insulating layer and the polymer electret in the OFET with the structure of gate-electrode/insulating layer/polymer/pentacene/source (drain) electrode. The thickness of n-type semiconductor layer is 1˜200 nm. The induced electrons at the interface of n-type semiconductor and polymer electret lead to the reduction of the height of the hole-barrier formed at the interface of polymer and pentacene, thus effectively reducing the programming/erasing (P/E) gate voltages of pentacene OFET, adjusting the height of hole barrier at the interface of polymer and pentacene to a reasonable scope by controlling the quantity of induced electrons in n-type semiconductor layer, thus improving the performance of pentacene OFET, such as the P/E speeds, P/E endurance and retention characteristics.

Abstract: Disclosed is a radial-axial air gap three-phase disc-type transverse flux permanent magnet motor. Each phase includes a stator consisting of shoe-shaped stator cores and shoe-shaped permanent magnets, and a radial-axial rotor. The permanent magnets are magnetized in the circumferential direction, and the magnetization directions of the two adjacent permanent magnets are opposite to each other. Armature windings are wound in the grooves formed by the alternately arranged stator cores and the permanent magnets. The radial-axial rotor includes radial teeth, axial teeth, and right-angled yokes. The radial teeth are connected to the axial teeth through the right-angled yokes. Adjacent radial/or axial teeth are spaced at a mechanical angle of 360/n degrees. Radial teeth and the adjacent axial teeth under the same pole pairs are spaced at a mechanical angle of 180/n degrees, where n is the number of pole pairs of the radial-axial air gap three-phase disc-type transverse flux permanent magnet motor.

Abstract: Provided is a Schizochytrium limacinum strain, a building method therefor and an application thereof. The strain disclosed is classified and named as Schizochytrium sp. HX-RS, and the preservation number is CCTCC NO: M2017046. An acyltransferase functional domain originating from Shewanella PKS enzyme is adopted instead of an acyltransferase functional domain originating from Schizochytrium sp. PKS enzyme, and the strain is obtained by performing flat panel screening and acclimation screening with a high rotation seed and a low temperature.

Abstract: The present disclosure provides a polarized Raman spectrum-based nano barcode smart label, including: a substrate and a nanoparticle coding layer that is provided on the substrate and can be coded by polarized Raman spectrum coding, wherein the nanoparticle coding layer that can be coded by polarized Raman spectrum coding is a mixed layer including a plurality of nanomaterials having different Raman characteristic peaks; under different polarization detection states, the Raman characteristic peaks can exhibit coding characteristics that are totally different from those under a non-polarization detection state and are distinguished from those of a conventional Raman peak position, so as to achieve spectral characteristics for multiple coding. During use of the smart label of the present disclosure, a corresponding nano barcode detection system is used to detect a brand label provided with the encoded nanoparticles to obtain coding information of the brand label.

Abstract: The present disclosure provides a four-dimensional imaging method for structural damage based on a time-invariant characteristic signal. The method first uses a probability statistical modeling method to describe the uncertainty distribution of the amplitude of each sampling point in the signal in the healthy state and the damaged state of the structure, respectively. Then the degree of difference between the two distributions at each point is measured to suppress the influence of the time-varying factor, highlight the influence of damage, and construct a time-invariant characteristic signal. Finally, the time-invariant characteristic signal of the pitch-catch channel is fused by using the guided wave imaging method to further enhance the influence of damage. Based on this, four-dimensional imaging is performed to achieve reliable and accurate location of structural damage.

Abstract: A wide-beam planar backfire and bidirectional circularly-polarized antenna. An entire planar sectorial magnetic dipole is of a semi-closed structure, the planar sectorial magnetic dipole comprises two identical sectorial patches and a vertical short-circuit wall, and the vertical short-circuit wall is connected with straight sides of the two sectorial patches along a radial direction of the planar sectorial magnetic dipole; two sets of concentric annular electric dipoles are respectively used as a top concentric annular radiating element and a bottom concentric annular radiating element, as well as a top concentric annular reflector and a bottom anti-concentric annular reflector; and the top concentric annular radiating element is connected with an upper surface of the planar sectorial magnetic dipole through a top connecting branch, and the bottom concentric annular radiating element is connected with a lower surface of the planar sectorial magnetic dipole through a bottom connecting branch.

Abstract: A method for enhancing the performance of pentacene organic field-effect transistor (OFET): an n-type semiconductor thin film was set as a buffer layer between pentacene and polymer electret in the OFET with the structure of gate-electrode/insulating layer/polymer/pentacene/source (drain) electrode. The thickness of n-type organic buffer layer is 1˜100 nm. The induced electrons at the interface lead to the reduction of the height of the hole-barrier formed at the interface, thus effectively reducing the programming/erasing (P/E) gate voltages of pentacene OFET. The widened distribution region of positive space charges caused by ionized donors in n-type organic buffer layer effectively restricts the back-transfer of holes from polymer to pentacene, thus improving the performance of pentacene OFET, such as the P/E speeds, P/E endurance and retention characteristics.

Abstract: Disclosed is an intelligent frequency-shift anti-interference autonomous communication method based on electromagnetic environment learning, applied to an intelligent frequency-shift anti-interference autonomous communication system based on electromagnetic environment learning. The method comprises a communication link establishing process and an intelligent frequency-shift anti-interference process in the communication process. In the communication link establishing process, a communication initiator initiates communication to a communication responder, and the communication initiator and the communication responder perform frequency point matching, and finally negotiate to establish a communication connection.

Abstract: The present invention discloses a three-dimensional diffraction tomography microscopy imaging method based on LED array coded illumination. Firstly, acquiring the raw intensity images, three sets of intensity image stacks are acquired at different out-of-focus positions by moving the stage or using electrically tunable lens. And then, after acquiring the intensity image stacks of the object to be measured at different out-of-focus positions, the three-dimensional phase transfer function of the microscopy imaging system with arbitrary shape illumination is derived. Further, the three-dimensional phase transfer function of the microscopic system under circular and annular illumination with different coherence coefficients is obtained as well, and the three-dimensional quantitative refractive index is reconstructed by inverse Fourier transform of the three-dimensional scattering potential function. The scattering potential function is converted into the refractive index distribution.

Abstract: An ultra-wideband ground penetrating radar control system, comprising a synchronous clock generating circuit, a GPS positioning module, a measuring wheel encoder module, a digitally controlled delay circuit for equivalent sampling, an analog-to-digital conversion (ADC) circuit, and a main controller. The synchronous clock generating circuit, the GPS positioning module, the measuring wheel encoder module, the digitally controlled delay circuit and the ADC circuit are all connected to the main controller. The synchronous clock generating circuit is further connected to an external ultra-wideband radar transmitter. The digitally controlled delay circuit is further connected to an external sampling pulse generation circuit for equivalent sampling. The ADC circuit is further connected to an external sampling gate for equivalent sampling. The main controller is further connected to an external server via Ethernet. The volume of an ultra-wideband ground penetrating radar control system is reduced.

Abstract: The invention discloses a deep learning-based temporal phase unwrapping method for fringe projection profilometry. First, four sets of three-step phase-shifting fringe patterns with different frequencies (including 1, 8, 32, and 64) are projected to the tested objects. The three-step phase-shifting fringe images acquired by the camera are processed to obtain the wrapped phase map using a three-step phase-shifting algorithm. Then, a multi-frequency temporal phase unwrapping (MF-TPU) algorithm is used to unwrap the wrapped phase map to obtain a fringe order map of the high-frequency phase with 64 periods. A residual convolutional neural network is built, and its input data are set to be the wrapped phase maps with frequencies of 1 and 64, and the output data are set to be the fringe order map of the high-frequency phase with 64 periods. Finally, the training dataset and the validation dataset are built to train and validate the network.

Abstract: A narrow pulse generation circuit used in a sequential equivalent sampling system. The circuit comprises a crystal oscillator, an edge sharpening circuit, an avalanche transistor single-tube amplifying circuit and a shaping network connected in sequence, wherein the edge sharpening circuit is used for carrying out edge sharpening on a square wave signal generated by the crystal oscillator; the avalanche transistor single-tube amplifying circuit is used for carrying out avalanche amplification on the sharpened square wave signal to generate a Gaussian pulse signal to adjust the amplitude of a pulse; and the RC shaping network is used for shaping the Gaussian pulse signal to adjust the pulse width at the bottom of the pulse to form a narrow pulse signal. The narrow pulse circuit has a simple structure and narrow pulse width at the bottom and facilitates increasing a signal-to-noise ratio of a whole sequential sampling system.

Abstract: The present disclosure provides a bandpass filter based on effective localized surface plasmons (ELSPs) and an operation method thereof. The bandpass filter includes a metal ground plane on a lower portion and a dielectric substrate in a middle as well as microstrips and dielectric resonators on an upper portion, where the microstrips at two terminals are symmetric with each other; each dielectric resonator includes a cuboid dielectric body and two metal strips, where the two metal strips each the same as the cuboid dielectric body in length are respectively located in a middle of an upper surface and lower surface of the dielectric body; and two microstrips are respectively connected to the metal strips on lower surfaces of two dielectric resonators, so as to be used as ports for feeding.

Abstract: A Quantum Digital Signature (QDS)-based mail system and a transceiving method are provided. The system is a three-layer structure formed by a physical layer, a key layer, and an application layer. The physical layer is a key generation terminal and is used to generate a key string for signature in real time; the key layer is used to store the key string generated by the physical layer and provide a required key to the upper layer, namely, the application layer when required; and the application layer is a transceiving software part in the mail system, and is used to extract keys generated by the physical layer from the key layer so as to encrypt information to be sent. The mail transceiving method comprises: a quantum key distribution (QKD) phase, a mail signature phase, and a signature verification phase.

Abstract: The patent discloses a differential phase contrast (DPC) quantitative phase microscopy method based on the optimal illumination pattern design. Firstly, the optimal illumination pattern corresponding to the isotropic phase transfer function of DPC quantitative phase imaging is derived, which is determined as a semi-annular illumination pattern with the illumination numerical aperture NAill equal to the numerical aperture NAobj of the objective lens. The illumination intensity distribution varies with the cosine of the illumination angle, and it can be expressed as S(?)=cos(?). This patent effectively compensates for the frequency loss of phase transfer, not only the high-frequency responses of PTF are enhanced, but also the transfer responses of low-frequency phase information is significantly improved.