Abstract: The present disclosure provides a method for preparing natural starch microspheres with a uniform particle size. The method includes the following steps: heating natural starch and water for gelatinization to form a water phase; controlling a temperature of a substance including a low-polarity solvent to form an oil phase; dispersing the water phase into the oil phase to obtain a mixed solution; treating the mixed solution under reduced pressure, and carrying out separation to obtain preliminarily solidified starch microspheres; and washing the preliminarily solidified starch microspheres to remove the residual oil phase on the surface, and drying to obtain the natural starch microspheres. Compared with the present technology, the method of the present disclosure can retain the molecular structure of the natural starch and has a high yield, and the prepared natural starch microspheres have a uniform particle size and can load water-soluble and fat-soluble loading objects.

Abstract: A mid-infrared gas sensor based on a tapered sub-wavelength grating slot waveguide comprises a lower cladding, a first tapered grating array and a second tapered grating array. The first tapered grating array and the second tapered grating array are disposed on an upper surface of the lower cladding. The first tapered grating array is located in front of the second tapered grating array. The first tapered grating array is formed by 5566 identical first core waveguides that are regularly distributed at intervals from left to right. The second tapered grating array is formed by 5566 identical second core waveguides that are regularly distributed at intervals from left to right. The first core waveguides and the second core waveguides are tapered waveguides. Upper sides and lower sides of the first core waveguides and the second core waveguides are isosceles trapezoids.

Abstract: A mid-infrared gas sensor based on a tapered sub-wavelength grating slot waveguide comprises a lower cladding, a first tapered grating array and a second tapered grating array. The first tapered grating array and the second tapered grating array are disposed on an upper surface of the lower cladding. The first tapered grating array is located in front of the second tapered grating array. The first tapered grating array is formed by 5566 identical first core waveguides that are regularly distributed at intervals from left to right. The second tapered grating array is formed by 5566 identical second core waveguides that are regularly distributed at intervals from left to right. The first core waveguides and the second core waveguides are tapered waveguides. Upper sides and lower sides of the first core waveguides and the second core waveguides are isosceles trapezoids.

Abstract: An antimycin compound and a preparation method and use thereof are provided. The preparation method comprises: fermenting a marine actinomycete (Steptomyces sp.4-7) with a preservation number CCTCCNO: M2020953 to obtain a fermented product and soaking and extracting the fermented product with ethyl acetate to obtain a crude extract; and carrying out separation and purification by normal-phase silica gel column chromatography, reversed-phase MPLC, and semi-preparative reversed-phase high-performance liquid chromatography. The antimycin compound has the advantages of resistance against Botrytis cinerea and Penicillium citrinum.

Abstract: Disclosed are a virtual parking space establishment system and a method. The virtual parking space establishment system includes a data acquiring module, a data processing module, a parking space control module, a wireless communication module and a client; the data acquiring module is used for acquiring traffic flow data; the data processing module is used for processing and analyzing the traffic flow data; the parking space control module is used for establishing or canceling virtual parking spaces according to analysis results of the traffic flow data; the wireless communication module is used for providing a wireless network link between the client and the parking space control module; the client is used for viewing virtual parking space information.

Abstract: A broadband panel array antenna includes a polarization layer, a radiating layer and a feed layer which are sequentially stacked from top to bottom. The feed layer is used for converting a single path of TE10 mode signals into a plurality of paths of same-power in-phase TE10 mode signals and transmitting the plurality of paths of TE10 mode signals to the radiating layer. The radiating layer is used for radiating the plurality of paths of TE10 mode signals from the feed layer to a free space. The polarization layer is used for rotating the polarization direction of an electric field generated by the radiating layer to reduce the side lobe in an E-plane direction diagram and an H-plane direction diagram. The broadband panel array antenna has the advantages of being low in side lobe, high in gain and efficiency, and low in machining cost.

Abstract: A method for preparing all-solid-state photonic crystal fiber preform by extrusion by aligning the center of the first jacking end of the first jacking rod with the center of the core outlet mold. The adverse effect on this part of extruded core glass by oxygen or other impurities in air during the extrusion out of the core outlets can be avoided. The defects on the core glass surface and the cladding glass surface can be effectively removed, and the purity and quality of the core component in the obtained fiber preform can be improved.

Abstract: A high-dimensional data nearest-neighbor query method based on variable-length hash codes is disclosed. Specifically, in this method, hash codes with the same code frequency are taken as a sub-data set, all the sub-data sets are ranked, a compression ratio is set for each sub-data set, the sub-data sets are compressed and trained according to the compression ratios, and hash codes and original codes corresponding to the trained sub-data sets are obtained; the hash code of each trained sub-data sets is copied to obtain multiple replicas, and the original codes and the corresponding replicas are strung to obtain strung hash codes which are integrated to form a final nearest-neighbor query table; and, a query code is obtained, and the nearest-neighbor query table is searched for a nearest-neighbor data set to complete query. The query efficiency and accuracy are greatly improved according to the invention.

Abstract: A reusable piezoelectric sensor for damage identification includes a piezoelectric ceramic plate and a metal box bonded to the surface of a test piece, where a wire through hole is formed in the center of a top plate of the metal box, and a side wall of the metal box extends vertically upwards to form a striking face for being struck to remove the metal box from the test piece; the piezoelectric ceramic plate arranged in the metal box is closely and fixedly bonded to a bottom plate of the metal box; and wires of the piezoelectric ceramic plate penetrate through the wire through hole to be connected to an external impedance analyzer. The reusable piezoelectric sensor for damage identification is easy to manufacture and convenient to operate and can effectively eliminate the testing error caused by the difference of the piezoelectric ceramic plate.

Abstract: A low-sidelobe plate array antenna includes a radiation layer and a feed layer. The radiation layer is superimposed on the feed layer and includes a first plate and a radiation array disposed on the first plate. The radiation array is formed by n2 radiation units which are distributed in 2(k-1) rows and 2(k-1) columns. Each radiation unit in the radiation layer is constituted by two first radiation assemblies and two second radiation assemblies. Each first radiation assembly comprises a first rectangular bar, a first rectangular cavity, a second rectangular cavity and a third rectangular cavity. The first rectangular cavity, the second rectangular cavity and the third rectangular cavity in the first radiation assembly are stacked in presence of an azimuth deviation to form a three-layer coupled structure, and the first rectangular bar located in the first rectangular cavity can better restrain cross polarization and reduce the sidelobe.

Abstract: The disclosure discloses a method for defending control flow attacks. When a data processor gives a response to an interrupt routine, a return address and a binary key are input to an encryption circuit to be encrypted to obtain an encrypted return address, and the obtained encrypted return address is synchronously written into a stack of the data processor and an built-in register bank; when the response given to the interrupt routine by the data processor is finished, the encrypted return address is read from the tack of the data processor and the built-in register bank; afterwards, the two encrypted return addresses are decrypted by first and second decryption circuits respectively to obtain two decrypted return addresses; and the two decrypted return addresses are compared to draw a conclusion whether the data process suffers from a control flow attack, and data processor determines to continue or terminate the routine accordingly.

Abstract: A broadband panel array antenna includes a polarization layer, a radiating layer and a feed layer which are sequentially stacked from top to bottom. The feed layer is used for converting a single path of TE10 mode signals into a plurality of paths of same-power in-phase TE10 mode signals and transmitting the plurality of paths of TE10 mode signals to the radiating layer. The radiating layer is used for radiating the plurality of paths of TE10 mode signals from the feed layer to a free space. The polarization layer is used for rotating the polarization direction of an electric field generated by the radiating layer to reduce the side lobe in an E-plane direction diagram and an H-plane direction diagram. The broadband panel array antenna has the advantages of being low in side lobe, high in gain and efficiency, and low in machining cost.

Abstract: A low-sidelobe plate array antenna includes a radiation layer and a feed layer. The radiation layer is superimposed on the feed layer and includes a first plate and a radiation array disposed on the first plate. The radiation array is formed by n2 radiation units which are distributed in 2(k-1) rows and 2(k-1) columns. Each radiation unit in the radiation layer is constituted by two first radiation assemblies and two second radiation assemblies. Each first radiation assembly comprises a first rectangular bar, a first rectangular cavity, a second rectangular cavity and a third rectangular cavity. The first rectangular cavity, the second rectangular cavity and the third rectangular cavity in the first radiation assembly are stacked in presence of an azimuth deviation to form a three-layer coupled structure, and the first rectangular bar located in the first rectangular cavity can better restrain cross polarization and reduce the sidelobe.

Abstract: A six-degree-of-freedom large-stroke uncoupling large hollow series-parallel piezoelectric micro-motion platform includes a base, a movable platform top, a second platform and a first platform, wherein a first guide unit, a second guide unit, a third guide unit, a fourth guide unit, a fifth guide unit and a sixth guide unit are respectively connected in sequence to the second platform and the first platform; the first guide unit is internally provided with a first drive unit, the second guide unit is internally provided with a second drive unit, and the third guide unit is internally provided with a third drive unit; and the base is provided with a fourth drive unit, a fifth drive unit, a sixth drive unit and a seventh drive unit, the fifth drive unit is provided below the second drive unit, and the sixth drive unit is provided below the third drive unit.

Abstract: The invention discloses a circuit aging detection sensor based on voltage comparison. A control circuit generates an aging voltage signal, a standard voltage signal and a reference voltage signal. The aging voltage signal passes through a first voltage-controlled oscillator to generate an aging frequency signal. The standard voltage signal passes through a second voltage-controlled oscillator to generate a standard frequency signal. The standard frequency signal and the aging frequency signal pass through an aging detection circuit to generate a frequency difference signal. A level signal generated by a serial data detector passes through a beat-frequency oscillator to generate a reset signal. A counter quantizes aging information, which is converted by a digital-analog converter into a quantized voltage signal. The quantized voltage signal is compared with the reference voltage signal by a voltage comparator, to generate a hopping signal at a voltage superposition node, and an aging signal is output.

Abstract: A domino full adder based on delayed gating positive feedback comprises a first PMOS transistor, a second PMOS transistor, a third PMOS transistor, a fourth PMOS transistor, a fifth PMOS transistor, a sixth PMOS transistor, a seventh PMOS transistor, an eighth PMOS transistor, a ninth PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a fifth NMOS transistor, a sixth NMOS transistor, a seventh NMOS transistor, an eighth NMOS transistor, a ninth NMOS transistor, a tenth NMOS transistor, an eleventh NMOS transistor, a first inverter, a second inverter, a third inverter and a fourth inverter.

Abstract: The disclosure discloses a lookup table-based circuit aging detection sensor, including a control circuit, two voltage controlled oscillators (VCOs), two shaping circuits, a phase comparator, a 3-digit voter, a beat-frequency oscillator, an 8-digit counter, a latch, a lookup table array and a digital-analogue converter. The control circuit respectively connects with the phase comparator, the 3-digit voter, the 8-digit counter, the first and the second VCOs. The first and second VCOs connect with the first and second shaping circuits respectively. The first and second shaping circuits connect with the phase comparator. The phase comparator connects with the 3-digit voter. The 3-digit voter connects with the beat-frequency oscillator. The beat-frequency oscillator respectively connects with the 8-digit counter and the latch. The 8-digit counter connects with the latch. The latch connects with the lookup table array. The lookup table array connects with the digital-analogue converter.

Abstract: A true random number generator based on a voltage-controlled oscillator includes a thermal noise generator, a ring oscillator, a voltage-controlled oscillator, a D flip-flop, and a post-processing circuit. The D flip-flop has a clock terminal, an input terminal, and an output terminal. An output terminal of the thermal noise generator is connected with an input terminal of the voltage-controlled oscillator. An output terminal of the voltage-controlled oscillator is connected with the clock terminal of the D flip-flop. An output terminal of the ring oscillator is connected with the input terminal of the D flip-flop. The output terminal of the D flip-flop is connected with an input terminal of the post-processing circuit. An input terminal of the thermal noise generator is connected with a reference level. The thermal noise generator includes a digital-analog converter, an operational amplifier, a first resistor, a second resistor, a third resistor, and a fourth resistor.

Abstract: A domino full adder based on delayed gating positive feedback comprises a first PMOS transistor, a second PMOS transistor, a third PMOS transistor, a fourth PMOS transistor, a fifth PMOS transistor, a sixth PMOS transistor, a seventh PMOS transistor, an eighth PMOS transistor, a ninth PMOS transistor, a first NMOS transistor, a second NMOS transistor, a third NMOS transistor, a fourth NMOS transistor, a fifth NMOS transistor, a sixth NMOS transistor, a seventh NMOS transistor, an eighth NMOS transistor, a ninth NMOS transistor, a tenth NMOS transistor, an eleventh NMOS transistor, a first inverter, a second inverter, a third inverter and a fourth inverter.

Abstract: The invention discloses a circuit aging detection sensor based on voltage comparison. A control circuit generates an aging voltage signal, a standard voltage signal and a reference voltage signal. The aging voltage signal passes through a first voltage-controlled oscillator to generate an aging frequency signal. The standard voltage signal passes through a second voltage-controlled oscillator to generate a standard frequency signal. The standard frequency signal and the aging frequency signal pass through an aging detection circuit to generate a frequency difference signal. A level signal generated by a serial data detector passes through a beat-frequency oscillator to generate a reset signal. A counter quantizes aging information, which is converted by a digital-analog converter into a quantized voltage signal. The quantized voltage signal is compared with the reference voltage signal by a voltage comparator, to generate a hopping signal at a voltage superposition node, and an aging signal is output.