Abstract: The disclosure belongs to the technical field of additive manufacturing, and discloses a flexible piezoelectric sensor based on 4D printing. The sensor includes a magnetic part and a conductive part, wherein: the conductive part includes two substrates disposed opposite to each other and a spiral structure disposed between the two substrates. Both the two substrates and the spiral structure are made of conductive metal materials. The magnetic part has a flexible porous structure and is arranged between the two substrates to generate a magnetic field. When the two substrates are subjected to external pressure, the spiral structure and the magnetic part are compressed simultaneously, the magnetic flux passing through the spiral structure changes, and the voltage of the two substrates changes, by measuring the voltage change of the two substrates to reflect the change of external pressure, the pressure measuring process is achieved.

Abstract: Disclosed are an OTS-based dynamic storage structure and an operation method thereof. The OTS-based dynamic storage structure includes a plurality of storage units distributed in an array, and each storage unit includes an OTS gating transistor and a storage capacitor. The OTS gating transistor has two states, namely, high resistance state and low resistance state. When the voltage across the OTS gating transistor exceeds the threshold voltage Vth, the OTS gating transistor is switched from the high resistance state to the low resistance state. When the voltage across the OTS gating transistor in the low resistance state is lower than the holding voltage Vhold, the OTS gating transistor is switched from the low resistance state to the high resistance state.

Abstract: A magnetic-field-adjustable micromagnetic orthodontic accelerator includes a cheek side plate, a tongue side plate and a supporting plate to form a structure of teeth sleeves, cheek side magnets and tongue side magnets are arranged on the cheek side plate and the tongue side plate respectively, the cheek side magnets and the tongue side magnets form a micro magnetic field environment around roots of to-be-moved teeth receiving orthodontic treatment, physiological magnetic field loss caused by traction of the orthodontic accessory is effectively compensated, metabolism and reconstruction of periodontal tissue of the to-be-moved teeth are promoted, and the orthodontic teeth moving process is accelerated.

Abstract: The disclosure provides a frequency support method, device and wind farm for a wind farm and belongs to the technical field of new energy power generation and grid connection. In the frequency support method, a state that can reflect a frequency modulation capability of a wind turbine is designed, measured, and recorded as a consistency factor of frequency modulation. Each wind turbine is controlled to exchange the consistency factors with two adjacent wind turbines. Each wind turbine combines its own consistency factors with the consistency factors of two adjacent wind turbines to generate consistent added power through a PI link and adjusts real-time frequency modulation output based on the consistency added power. In this way, the states of the wind turbines in the wind farm are similar during the frequency support process, so that a reasonable distribution of frequency support power is achieved.

Abstract: Disclosed are a method and a system for correlating hydro-turbine governing system control parameters and oscillation characteristics, and the method includes the steps: calculating a eigenvalue, a zero point and a pole of a state matrix in a hydro-turbine governing system state space model, taking a pole which is the closest to the imaginary axis and has no zero point in a preset distance as a dominant eigenvalue; determining an oscillation characteristic region of the hydro-turbine governing system on the complex plane according to the dominant eigenvalue; obtaining a system control parameter stability domain according to a Hurwitz stability criterion; and calculating dominant eigenvalues corresponding to different control parameters, classifying the control parameters according to an oscillation characteristic region of a complex plane where the dominant eigenvalue is located, and dividing the oscillation characteristic region in a system control parameter stability domain.

Abstract: A high-speed and large-current adjustable pulse circuit, an operating circuit and an operating method of a phase-change memory are provided. The high-speed and large-current adjustable pulse circuit is provided with a clamping structure, a current mirror structure and a leakage current shutdown structure. The clamping structure including a clamping operational amplifier and a first MOS transistor is configured to generate a reference current. The current mirror structure is configured to generate an output current proportional to the reference current. The leakage current shutdown structure is configured to turn off the current mirror structure and reduce leakage current when pulse disappear. In this way, a device with an adjustable current and a reduced leakage current is realized.

Abstract: A nonlinear optical device includes two coupling systems. A coupling coefficient between the two coupling systems is regulated and controlled. During operation, the pump light input from a straight waveguide is coupled into the second coupling system through the first coupling system and obtains great resonance enhancement in the second coupling system, so it is ensured that the second coupling system is in a high energy state. For signal light input from the same end of the straight waveguide, the signal light enters a resonator of the second coupling system through the coupling between the first and second coupling systems. A nonlinear effect of the system mainly occurs in the resonator of the second coupling system because in the resonator of the second coupling system, the pump light is in a great resonance enhancement. The entire resonator is in a high energy state.

Abstract: A holographic wavefront printing system and method are provided. A two-dimension digital blazed grating is loaded on a phase hologram, and the emergent direction of active region diffracted light is adjusted to prevent overlapping with the dead region diffracted light after being Fourier transformed by a lens, and a phase spatial light modulator is inclined by a preset angle to change the emergent direction of the diffracted light, such that the dead region zeroth-order and first-order diffracted light on a focusing surface are symmetrical with respect to a main optical axis of a first lens, the frequency spectrum center of active region zeroth-order diffracted light is then loaded to the original frequency spectrum center without information change. In this way, the adverse effects of the dead region diffracted light and active region high-order diffracted light of the phase spatial light modulator on holographic wavefront printing are eliminated.

Abstract: The disclosure belongs to the technical field related to additive manufacturing model preprocessing, and discloses a field-based additive manufacturing digital model feature identification and extraction method and device, the method can convert the digital model represented by the facet into a signed distance field and introduce a simulated physical field of the forming/service simulation, the feature distance field after the frequency domain analysis filtering, and the geometric feature field obtained by the multi-precision convolution unit analysis according to the requirement of feature to be identified, then, multiple fields are combined to realize feature classification determination and labeling of features, and finally feature extraction is completed based on field data and isosurface and isoline reconstruction algorithms.

Abstract: Disclosed are a method for processing and recycling an ultrathin lithium foil and a product, which belongs to the field of lithium-ion batteries. According to the disclosure, a liquid-phase thinning agent is adopted to perform a contact reaction with a lithium metal, the fabricated ultrathin lithium foil has a thickness of 20 ?m or less, the surface is flat, the thickness can be randomly regulated, and the uniformity is good. The method of the disclosure can also recycle a lithium-containing byproduct generated in the preparation process. When the ultrathin metal lithium foil prepared by the disclosure is used as a metal lithium negative electrode of a lithium battery, the energy density of the battery can be improved, and the battery manufacturing cost is reduced. The ultrathin metal lithium foil can also be used to supplement lithium for other types of electrode materials, thereby a broad application prospect is achieved.

Abstract: The disclosure provides a frequency support method, device and wind farm for a wind farm and belongs to the technical field of new energy power generation and grid connection. In the frequency support method, a state that can reflect a frequency modulation capability of a wind turbine is designed, measured, and recorded as a consistency factor of frequency modulation. Each wind turbine is controlled to exchange the consistency factors with two adjacent wind turbines. Each wind turbine combines its own consistency factors with the consistency factors of two adjacent wind turbines to generate consistent added power through a PI link and adjusts real-time frequency modulation output based on the consistency added power. In this way, the states of the wind turbines in the wind farm are similar during the frequency support process, so that a reasonable distribution of frequency support power is achieved.

Abstract: The disclosure discloses a low-loss transmission line structure, which belongs to the field of radio frequency transmission lines and includes at least two metal layers stacked in a vertical manner. A dielectric layer is filled between the metal layers. The metal layers include a signal transmission strip in a middle portion. Ground strips are provided on both sides of the signal transmission strip. Through holes are evenly distributed on the dielectric layer, and the signal transmission strips on each of the metal layers are connected through the through holes to form a signal transmission line. The ground strips on each metal layer are connected through the through holes.

Abstract: A holographic wavefront printing system and method are provided. A two-dimension digital blazed grating is loaded on a phase hologram, and the emergent direction of active region diffracted light is adjusted to prevent overlapping with the dead region diffracted light after being Fourier transformed by a lens, and a phase spatial light modulator is inclined by a preset angle to change the emergent direction of the diffracted light, such that the dead region zeroth-order and first-order diffracted light on a focusing surface are symmetrical with respect to a main optical axis of a first lens, the frequency spectrum center of active region zeroth-order diffracted light is then loaded to the original frequency spectrum center without information change. In this way, the adverse effects of the dead region diffracted light and active region high-order diffracted light of the phase spatial light modulator on holographic wavefront printing are eliminated.

Abstract: Disclosed are a vectorial rotation velocity measurement method and device based on multi-core fiber, which belongs to the field of optical measurement. Input multiple lights are transmitted through a non-uniformly distributed space to form a structured non-uniform spatially-distributed scalar light field, wherein the scalar light field serves as a collimated probe light to illuminate rotationally moving particles, the rotationally moving particles reflect a signal light carrying motion information, the signal light is subjected to a Fourier analysis to obtain a Fourier amplitude spectrum and a Fourier phase spectrum, a velocity of the rotationally moving particles is calculated through a frequency peak in the Fourier amplitude spectrum, and a direction of the velocity of the rotationally moving particles is calculated using a relative phase difference value corresponding to the Fourier phase spectrum, thereby realizing a measurement of vectorial rotationally moving particles based on the multi-core fiber.

Abstract: The disclosure discloses a reconfigurable heterojunction memristor, a control method, a fabrication method, and an application thereof. The functional layer designed by the disclosure comprises a PN heterojunction of n-AgO and p-Ag2O or a PN heterojunction of n-CuO2 and p-CuO. In the analog type, multiple resistance state performance is exhibited based on charge trapping and releasing, and self-rectification characteristics are exhibited, without the need for a selector, which facilitates large-scale integration; in the digital type, the presence of Ag/Cu ions in the layer helps to form Ag/Cu conductive filaments, the switching threshold voltage is small, and the advantages of fast switching speed and low switching power consumption are provided. The disclosure realizes a PN heterojunction device of an N-type oxide layer and a P-type oxide layer through electrochemical principles, and is analog type-digital type reconfigurable between a self-rectifying analog type device and a digital type device.

Abstract: The disclosure provides a convolution operation accelerator and a convolution operation method and belongs to the field of microelectronic devices. Input data of each word line may be subjected to a multiply-accumulate operation together with two upper and lower layers of convolution kernel units, so that natural sliding of the convolution kernel units in a y direction in two-dimensional input is achieved. The oblique bit lines and multiple copies of a convolution kernel in each layer of a non-volatile memory array may enable a multiplication operation between one piece of input data and convolution kernel data at different positions in the same convolution kernel. In this way, the natural sliding of the convolution kernel units in an x direction in the two-dimensional input is achieved.

Abstract: The disclosure provides a method and system for trajectory tracking control of a vehicle-manipulator coupling system with finite time prescribed performance. Specifically, the trajectory tracking error of the vehicle-manipulator coupling system is obtained. A finite time performance function is designed to constrain the trajectory tracking error. In a case the constraint conditions corresponding to the finite time performance function are satisfied, the trajectory tracking error is converted to obtain a transformed error. The sliding mode surface is designed based on the transformed error to control the transformed error to converge in a finite time, and the external disturbance of the vehicle-manipulator coupling system is observed based on non-linear disturbance observer. The control input of the vehicle-manipulator coupling system is designed based on the sliding mode surface and the non-linear disturbance observer output.

Abstract: The disclosure provides a method and a system for calculating a stability margin domain of the control parameters of a hydraulic turbine regulating system, which belongs to the technical field of stability margin analysis of the hydraulic turbine regulating system. The method includes: determining a high-order state space model of the hydraulic turbine regulating system; determining a dominant eigenvalue and an interference eigenvalue of a state matrix of the high-order state space model; determining an associated state variable of the interference eigenvalue; determining the interference eigenvalues under different target control parameter conditions; determining whether a target control parameter meets a stability margin requirement; and determining the stability margin domain of the control parameter.

Abstract: The present disclosure provides a data storage system, including data cache module, data processing module, and a persistent memory. The data cache module includes an on-chip mapping data cache and an on-chip counter cache, where the mapping data cache is configured to cache mapping data, and when the free space of the mapping data cache is less than a preset threshold, the least recently used mapping data cache line will be evicted from the cache and written back to the persistent memory. The data processing module encrypts/decrypts persistent memory data by using their counters, and accesses the persistent memory blocks indicated by their corresponding mapping data. The persistent memory comprises the first and second storage regions for the latest checkpoint data and modified working data in the current checkpoint interval respectively.

Abstract: A method for forming a multi-material mechanical functional member in additive manufacturing. The method includes the following steps: S1: dividing an object to be formed into a plurality of portions, analyzing and measuring mechanical properties of each portion, and constructing a unit cell library; S2: forming a lattice structure by using a unit cell structure in the unit cell library to obtain the lattice structure corresponding to each portion; S3: selecting a raw material of the lattice structure, measuring and comparing mechanical properties of each lattice structure with the mechanical properties of each portion of the object to be formed, where when the mechanical properties of each portion are satisfied, the lattice structure is the required lattice structure, otherwise, step S2 is repeated; and S4: forming a three-dimensional model by a method of additive manufacturing to accordingly obtain the required object to be formed.