175 results about "Electromechanical coupling" patented technology

Disclosed in the present invention is a physics-informed neural network-based thermo-mechanical coupling analysis method for an inertial microsystem, the method comprising: S1, configuring material parameters and boundary conditions of an inertial microsystem, and establishing a thermo-mechanical coupling analysis model; S2, performing electro-thermal coupling analysis to obtain a temperature distribution of the inertial microsystem; S3, performing thermo-mechanical coupling simulation analysis to obtain a thermal stress distribution of the microsystem; S4, predicting temperature fields of the microsystem by means of a physics-informed neural network; S5, using the temperature fields as boundary conditions for mechanical simulation of the microsystem, obtaining mechanical properties such as stress and strain of the microsystem; and S6, performing electromechanical coupling simulation analysis to analyze the impact of structural deformation on various parameters of electrical performance. The present invention improves the solution accuracy of the neural network by means of an improved adaptive weighting strategy, combines a complete polynomial basis function with the neural network, and introduces an expanded basis function to reduce the state dimensionality, thus reducing computational costs and time, achieving accurate prediction of temperature fields of microsystems at multiple moments, and allowing for computation of the performance of microsystems under electro-thermal-mechanical multi-physics coupling.

The invention discloses a micro-cantilever geometric structure parameter inversion system, method and device, and belongs to the technical field of micro-electro-mechanical systems. According to the system, a dynamic model containing geometry, material and electromechanical coupling nonlinearity is constructed, a PINNs network fused with physical constraints is designed, a staged training optimization strategy is adopted, and efficient inversion of micro-cantilever geometric parameters is achieved. The core of the method is that a nonlinear kinetic equation is used as a constraint to be embedded into a neural network for training, experimental data and physical residual errors are combined to construct a composite loss function, and the problems that a traditional method neglects a nonlinear effect, depends on finite element simulation and is low in inversion precision are solved. The average relative error of inversion of the system is lower than 1%, which is obviously superior to that of a traditional method, and the method can be widely applied to MEMS device design, online detection and closed-loop control scenes.

The invention relates to the technical field of electromechanical coupling damage diagnosis, and discloses a wind and light storage system electromechanical coupling damage diagnosis method and system.The wind and light storage system electromechanical coupling damage diagnosis method includes the steps that according to geometric data, material attributes and load data of a welding point area, a finite element mechanical model is constructed, and stress distribution data is calculated; according to the environment data and the electrochemical data, a corrosion kinetic model is constructed, and corrosion product parameters are obtained; according to the corrosion product parameters, an elastic modulus degradation model is established, and an inherent frequency degradation value and vibration mode displacement are obtained; performing vibration response analysis on the junction box according to the inherent frequency degradation value and the vibration mode displacement to obtain a stress concentration coefficient; and inputting the electrical parameter variation and the stress concentration coefficient into a damage failure evaluation model to obtain a damage failure evaluation result of the electrical connection point. Through the multi-dimensional coupling model and the dynamic parameter closed-loop feedback mechanism, the electromechanical coupling damage assessment accuracy is effectively improved, and the operation safety and the operation and maintenance efficiency of the wind and light storage system are improved.

The invention relates to the technical field of power grid stability analysis, in particular to a mechanical vibration micro-grid electromechanical coupling system stability analysis method, which comprises the following steps of: detecting a tooth surface contact radius, a relative speed and a Young modulus to generate a contact stiffness initial value, correcting nonlinear stiffness by interval difference, and calculating the stability of a micro-grid electromechanical coupling system. The method comprises the following steps: calculating a coupling response vector by combining rotor displacement and bearing clearance, inputting a Lyapunov exponent method to solve an exponent vector, constructing a model length ratio to detect derivative characteristics, extracting a multidimensional state vector in a positive value period and the coupling response vector to generate a compensation action, and constructing an FPGA simulation path injection disturbance execution error feedback back-transmission fuzzy control algorithm. According to the method, a contact stiffness dynamic correction and nonlinear difference method is introduced, six-degree-of-freedom displacement and bearing clearance parameters are combined, an electromechanical coupling model is established, a stability boundary is recognized through Lyapunov regression, a critical state is detected through derivative features, and multi-dimensional state vector fuzzy control compensation is fused. And the response and the immunity are optimized by combining FPGA simulation and a disturbance mechanism.

The invention belongs to the field of wind tunnel experiments in a hypersonic flow field environment, and discloses a multi-degree-of-freedom high-frequency motion simulation device for an aircraft dynamic stability test and a calculation method for realizing an actuation angle. According to the technical method, calculation is carried out on the basis of an electromechanical coupling equation, determined by electrical parameters and mechanical parameters, of a piezoelectric material. Modeling can be carried out according to a piezoelectric equation to obtain a calculation method between the voltage applied by the piezoelectric actuator and the pitching and yawing actuation angles of the device, so that the excitation effect of the device in the ground test process can be accurately controlled and predicted. The method is not only suitable for pitching and yawing two-degree-of-freedom actuation calculation, but also can be used for calculating the actuation angle of a three-axis degree-of-freedom experimental device added with rolling drive through coordinate transformation under the condition of adding parameters such as rolling angular velocity and the like in the face of the three-axis degree-of-freedom experimental device added with rolling drive. At present, according to a calculation method based on the device, calculation is carried out only by considering the degree of freedom of the pitching axis and the yawing axis.

The invention relates to the technical field of data processing, in particular to a gearbox service life evaluation method and system. The method comprises the following steps of collecting shaft current of a gearbox under an electromechanical coupling working condition, carrying out current characteristic association on each bearing, and generating a current characteristic sequence of each bearing; according to the current characteristic sequence of each bearing, judging the main circulation path and branch of the current between a gear meshing pair in the gear box, and carrying out electric corrosion damage evaluation to generate a bearing-tooth surface electric corrosion damage ratio; calculating a fatigue life reduction coefficient of the part according to the bearing-tooth surface electric corrosion damage ratio, and performing dynamic linear damage accumulation treatment to obtain a fatigue damage contribution value of each part in a period; evaluating the service life of the gearbox according to the fatigue damage contribution value of each part in the cycle, and generating the residual life percentage of the gearbox. According to the method, the residual life of the gearbox under the electromechanical coupling working condition is accurately predicted through collaborative evaluation of the electric corrosion damage and the vibration amplification effect.

The invention relates to the technical field of resonators, and discloses an MEMS resonator and a composite preparation method thereof.The composite preparation method of the MEMS resonator comprises the steps that a highly-doped first monocrystalline silicon layer is formed to serve as a supporting substrate; forming a piezoelectric material layer on the first monocrystalline silicon layer; forming a seed layer on the piezoelectric material layer at a first set rate, epitaxially forming a main body layer on the seed layer at a second set rate, and compounding the seed layer and the main body layer to form a highly doped second monocrystalline silicon layer; deep reactive ion etching is carried out on the laminated structure layer constructed based on the first monocrystalline silicon layer, the piezoelectric material layer and the second monocrystalline silicon layer, a resonator body, a connecting beam and an anchoring part are formed, and the resonator body is arranged in a suspended mode and connected with the anchoring part through the connecting beam. According to the invention, the electromechanical coupling efficiency and the quality factor of the MEMS resonator are improved, and the temperature stability of the MEMS resonator is ensured.

The invention discloses an acoustic wave filter based on an AlN / AlGaN superlattice structure and a preparation method of the acoustic wave filter, and relates to the technical field of filters, the acoustic wave filter comprises a superlattice main body, and is characterized in that the superlattice main body comprises a substrate and a piezoelectric superlattice layer located on one side of the substrate; wherein the substrate is a Si substrate, a sapphire substrate or a SiC substrate; the piezoelectric superlattice layer is a composite alternating layer of an AIN layer and an Al < x > Ga < 1-x > N layer, and x is a constant greater than 0. The invention has the effects of reducing strain, improving compatibility and reliability, being suitable for high-frequency operation and remarkably improving electromechanical coupling performance.

The invention discloses a mine electromechanical equipment operation safety situation assessment method and system, and relates to the technical field of mine electromechanical equipment safety monitoring and assessment, and the method comprises the following steps: building an electromechanical coupling time frequency observation layer, continuously obtaining the dynamic characteristics of tension data, displacement data, current data and torque data, generating a modal fingerprint baseline based on conjoint analysis; coherent decomposition is carried out under the support of the modal fingerprint baseline, the modal drift speed is calculated, and the risk window with the driving frequency gradually approaching is identified, so that the frequency evolution trend is revealed in advance. According to the method, an electromechanical coupling time-frequency observation system is constructed, a modal fingerprint baseline is extracted, the resonance risk is recognized in advance in combination with coherent decomposition and anti-fact playback, energy dissipation is achieved through peak shifting driving and structural damping, and finally, phase traction and a phonon band gap structure are used for rapid vibration extinguishing, so that a complete dynamic regulation and control closed-loop system is formed.

The invention relates to a filter integrating a fundamental wave resonator and a harmonic wave resonator and a manufacturing method of the filter, the fundamental wave resonator and the harmonic wave resonator are resonators in a thickness extension vibration mode, the fundamental wave resonator and the harmonic wave resonator are integrated on a single chip in a single crystal mode, the stack acoustic phase length hph of the fundamental wave resonator and the harmonic wave resonator is close to pi n, n is a harmonic order, and the acoustic phase lengths of the dielectric layers of the fundamental wave resonator and the harmonic wave resonator approach to pi (n-1). Dielectric layers with different thicknesses are arranged in a fundamental wave resonator area and a harmonic wave resonator area, the acoustic phase length of the dielectric layers of the fundamental wave resonator and the harmonic wave resonator is pi (n-1), the fundamental wave resonator and the harmonic wave resonator are integrated on a single chip, and therefore a wider frequency range and more suitable electromechanical coupling are achieved.

Techniques for improving acoustic resonators and resonator structures are disclosed, including filters, oscillators and systems that may include such devices. A bulk acoustic wave (BAW) resonator may comprise a substrate. The bulk acoustic wave (BAW) may further comprise a plurality of piezoelectric layers including first, second, third and fourth piezoelectric layers acoustically coupled with one another and arranged over the substrate. The first, second, third and fourth piezoelectric layers may have respective piezoelectric axis orientations. The first, second, third and fourth piezoelectric layers may have respective thicknesses. Electromechanical coupling of the bulk acoustic wave (BAW) resonator may, but need not be limited.

The present invention discloses a thermomechanical coupling analysis method for an inertial microsystem based on a physical information neural network, comprising: S1, setting the material parameters and boundary conditions of the inertial microsystem and establishing a thermomechanical coupling analysis model; S2, obtaining the temperature distribution of the inertial microsystem through electrothermal coupling analysis; S3, obtaining the thermal stress distribution of the microsystem through thermomechanical coupling simulation analysis; S4, predicting the temperature field of the microsystem through a physical information neural network; S5, using the temperature field as the boundary condition for the mechanical simulation of the microsystem to obtain the mechanical properties such as stress and strain of the microsystem; S6, performing electromechanical coupling simulation analysis to analyze the influence of structural deformation on various parameters in the electrical properties. The present invention improves the solving accuracy of the neural network through an improved adaptive weight strategy, combines the complete polynomial basis function with the neural network, introduces the expanded basis function to reduce the state dimension, reduces the computational cost and time, realizes the accurate prediction of the temperature field of the microsystem at multiple moments, and calculates the performance of the microsystem under the coupling of electrothermal and mechanical multi-physical fields.

The invention relates to the field of motor and gear transmission systems, in particular to a method for optimizing design parameters of a transmission gear in an electric drive system.The method includes the steps that firstly, a two-dimensional finite element model of a permanent magnet synchronous motor is established, rotor stepped skewed slots and material magnetic saturation characteristics are accurately simulated, and an external characteristic MAP is generated; then calculating electromagnetic force density based on a Maxwell stress tensor method, mapping the electromagnetic force density to a multi-body dynamic model to construct a transverse coupling model, extracting an ECE reduced-order model based on a permanent magnet synchronous motor two-dimensional finite element model, forming a torsional vibration model in combination with a control algorithm, integrating a rigid-flexible coupling mechanical system, and establishing an electromechanical-rigid-flexible coupling model; and finally, through sensitivity analysis and a response surface model, with vibration acceleration and torsion amplitude as targets and gear strength as constraints, a Pareto optimal solution is solved by adopting a genetic algorithm, electromechanical coupling simulation precision is greatly improved, system vibration is effectively reduced, gear transmission reliability is enhanced, and the method is suitable for design of a high-dynamic-performance electric drive system.

The invention relates to a prospective control method of a multi-axis linkage machine tool in the field of intelligent manufacturing, which comprises the following steps: by analyzing the time difference distribution of each axis in a compensation time sequence, establishing a dynamic compensation matrix of multi-axis linkage, the matrix comprising the advanced starting time and speed regulation coefficient of each axis in different motion stages, determining personalized motion control parameters of each axis; according to the updated delay characteristic data and the curvature radius information of the track corner, the position deviation trend of each axis in the corner machining process is predicted, whether the motion time sequence of each axis needs to be adjusted or not is judged by comparing the deviation degree of the predicted position and the theoretical track, and an optimized multi-axis cooperative motion instruction is obtained; and the optimized multi-axis cooperative motion instruction is input into a servo controller of each axis, an actual position feedback signal of each axis is monitored at the same time, and the response consistency of each axis is ensured by calculating the real-time deviation value of an actual track and a theoretical track and dynamically correcting compensation parameters in an electromechanical coupling delay model.

The invention belongs to the technical field of power distribution network hot-line work robots, and provides an electromechanical coupling system multi-parameter collaborative optimization method based on a GRPO reinforcement learning algorithm, and the method comprises the steps: obtaining multi-parameter operation data of an electromechanical coupling system in an operation process; carrying out preprocessing on the obtained operation data; constructing a state vector based on the preprocessed operation data; constructing a GRPO reinforcement learning collaborative optimization model based on a GRPO reinforcement learning algorithm; inputting the state vector into a GRPO reinforcement learning collaborative optimization model; and the GRPO reinforcement learning collaborative optimization model obtains an optimization strategy through interactive learning with the electromechanical coupling system. The method is based on a reinforcement learning framework, so that the optimization strategy can adapt to parameter drift caused by system operation condition change, environment interference and part aging in real time, and the robustness of the optimization effect is kept.

The invention relates to an electromechanical coupling characteristic-based electric drive system double-layer active torsional vibration suppression method, which belongs to the technical field of electric automobile motors and comprises the following steps of S1, establishing a permanent magnet synchronous motor mathematical model, an electric drive system helical gear pair kinetic model and a gear transmission lumped parameter model; s2, establishing an upper-layer state feedback control method based on pole assignment, including establishing a transmission system dynamic state space equation, a state observer and a state feedback controller; and S3, establishing a lower torsional vibration suppression method based on active-disturbance-rejection control. According to the invention, voltage deviation generated by nonlinearity of the inverter is compensated, and current harmonics and torque fluctuation are reduced; according to the invention, the damping ratio at the pole corresponding to the inherent frequency which easily causes resonance is improved, the low-frequency torsional vibration is reduced, and the time for reaching the steady state is shortened; according to the invention, current harmonics and torque ripples are reduced, and high-frequency torsional vibration of an electric drive system is reduced.

The invention discloses a high-performance dielectric elastomer film, a driver capable of being driven at low voltage and a preparation method of the driver. According to the preparation method of the high-performance dielectric elastomer film, customization and balance of mechanical properties and electrical properties of a dielectric elastomer are realized by regulating and controlling the proportion of a chemical cross-linking agent, a high-polarity physical cross-linking agent and a monomer; according to the preparation method of the driver capable of being driven at the low voltage, a dielectric elastomer film and a flexible electrode are stacked through an optimized dry stacking method, the dielectric elastomer driver of a multilayer structure is constructed, and the driver has excellent performance under the low driving voltage. The preparation method has the potential of large-batch and large-scale production, and the prepared dielectric elastomer film has low Young modulus and enhanced strain hardening effect, can avoid electromechanical coupling instability, has high dielectric constant, has large-area strain in a low electric field, and can be used for preparing a dielectric elastomer film. The resulting dielectric elastomer driver can have a blocking force of 0.8 N and an energy density of 80 J / kg at a voltage of 500 V.

System and methods for a hollow-disk radial-contour mode resonator structure. The hollow disk reduces the dynamic mass and stiffness of the structure. Since electromechanical coupling Cx / Co goes as the reciprocal of mass and stiffness, the hollow disk structure has a considerably stronger electromechanical coupling than a solid one at the same frequency, and thus raises Cx / Co without excessive gap-scaling. Several embodiments of hollow disk resonators are detailed, including asymmetric and symmetric disk configurations.

The application provides a detection system for interface peeling defects of a steel shell inner wall and concrete, which comprises a detection device, and the detection device comprises a signal generator, a signal amplifier, a plurality of piezoelectric material sheet assemblies, a signal acquisition assembly and a data analysis processor which are electrically connected in sequence; the plurality of piezoelectric material sheet assemblies are attached to the outer wall of the steel shell at intervals to form an electromechanical coupling system. The piezoelectric material sheet is arranged on the outer wall of the steel shell of the steel shell concrete component as a driver and a sensor at the same time, the electromechanical coupling impedance spectrum of the piezoelectric material is measured in a self-generating and self-receiving mode, the abnormal value of the electromechanical coupling impedance spectrum is analyzed, the RMSD of the electromechanical coupling impedance spectrum of the measuring point and the reference measuring point is calculated, the sensor position corresponding to the abnormal signal is screened out, and thus the accurate positioning and range estimation of the interface peeling defects are realized.

The invention discloses a fault detection method for an explosion-proof and intrinsic safety type hybrid electric appliance switch based on artificial intelligence, and relates to the technical field of intelligent operation and maintenance of power equipment, and the method comprises the following steps: S1, synchronously collecting multi-modal sensing data during the operation of the hybrid electric appliance switch through a plurality of intrinsic safety type sensors synchronously driven by a unified clock source; the multi-mode sensing data at least comprises electrical sensing data and mechanical vibration sensing data. According to the fault detection method for the flame-proof and intrinsic safety type hybrid electric appliance switch based on artificial intelligence, through a multi-mode synchronous acquisition and deep fusion architecture, the technical problem that fault feature acquisition is incomplete and asynchronous under strict explosion-proof constraints is effectively solved. Through a processing mechanism of edge calculation and cloud collaboration, accurate capture and intelligent screening of electromechanical coupling features are realized, the accuracy and reliability of fault diagnosis are improved by combining dual verification and a confidence fusion decision model, and effective technical support is provided for early fault early warning.

Mechanically and piezoelectrically anisotropic polymer fibers may be formed by spinning a polymer solution or gel that includes a high molecular weight crystallizable polymer and a liquid solvent. The solvent may be configured to interact with the polymer to facilitate chain alignment and, in some examples, create a higher crystalline content within the spun fibers. The polymer solution may also include a low molecular weight additive. The high and low molecular weight polymers may each be characterized by a bimodal molecular weight distribution where the molecular weight of the additive is less than the molecular weight of the crystallizable polymer. The polymer(s) and the additive(s) may be independently selected from vinylidene fluoride, trifluoroethylene, chlorotrifluoroethylene, hexafluoropropene, vinyl fluoride, etc. The spun fibers may be oriented, annealed, poled, and woven or laminated to form a polymer thin film having a high elastic modulus and a high electromechanical coupling factor.

The application discloses a dynamic reliability evaluation method for a permanent magnet planetary gear transmission system, and belongs to the technical field of reliability analysis of electromechanical coupling transmission systems. The method is characterized in that: firstly, the service process of the system is divided into stages, and a random variable model is established; based on the wear evolution relationship, parameters of each stage are obtained through parameter mapping; then, stage high-fidelity unified electromechanical dynamics solving is performed, and frequency-related characteristic indexes are extracted; a multi-failure mode limit state vector is constructed, and a stage failure event is defined; on this basis, a multi-response Gaussian process proxy model is used for fitting and iterative updating of the limit state function through stage-by-stage active learning; the U function is used for initial screening of candidate samples, EFF is calculated and sorted, and a new sample point is selected according to the Top-K criterion to update the proxy model, until the convergence criterion is met; finally, the dynamic failure probability of the system is calculated by using the updated proxy model. The application realizes efficient and accurate evaluation of the failure probability of multiple failure modes, reduces the calculation cost, and improves the engineering applicability.

The invention belongs to the technical field of functional materials, and particularly relates to a 1-3 type lead metaniobate piezoelectric composite material and a preparation method and application thereof. The composite material takes lead metaniobate ceramic with a tungsten bronze structure as a one-dimensional piezoelectric phase and takes epoxy resin as a three-dimensional polymer phase. The ratio [lambda] / T of the transverse periodic dimension ([lambda]) of the ceramic column to the thickness (T) of the composite material is 0.1-0.6. The preparation method is characterized in that the ceramic column array is formed through precise cutting, cutting parameters are controlled to achieve the lambda / T ratio, and then resin encapsulation, curing, polishing and electrode preparation are conducted. According to the invention, the electromechanical coupling performance and stability of the composite material at ultrahigh temperature are synergistically improved by selecting the lead metaniobate ceramic with high Curie temperature and combining specific lambda / T structural parameters. The obtained material can still keep good performance at 350 DEG C, the maximum thickness electromechanical coupling coefficient kt can reach 0.35, and the material is suitable for high-temperature acoustic logging and underwater acoustic receiving transducers.

The invention provides a double-drive synchronous control method and system for a gantry machine tool, and the method comprises the steps: S1, building a flexible multi-body dynamic model of the gantry machine tool through combining the part flexibility and connection flexibility of the gantry machine tool; s2, constructing a dual-drive electromechanical coupling model of the gantry machine tool by combining servo system characteristics of the gantry machine tool and traditional system dynamic characteristics on the basis of the flexible multi-body dynamic model; and S3, according to the double-drive electromechanical coupling model, a self-adaptive control algorithm combining cross coupling double-drive synchronous control and sliding mode control is adopted to complete synchronous control of a double-drive system. According to the gantry machine tool double-drive synchronous self-adaptive control algorithm based on cross coupling double-drive synchronous control and sliding mode control, a cross feedback item is introduced, so that information of two drivers is correlated, the problem of double-drive synchronous error accumulation faced by a traditional double-drive parallel control or master-slave control method of a gantry machine tool is solved, and the system reliability is improved. The synchronous control of the gantry machine tool servo double-drive system is realized.

This invention discloses a nonlinear dynamic modeling method for crack evolution in a helical gear transmission system for vehicles, which includes the following steps: (1) establishing a calculation formula for meshing stiffness of the helical gear pair under cracked conditions using the slice integration method and the potential energy method; (2) establishing an equivalent circuit model of the motor by combining the principles of circuit theory and magnetic circuit theory with coordinate transformation relationship; (3) building an electromechanical coupling model of the motor-gear system based on the mechanical relationship between the motor and the gear transmission system; (4) establishing a model of the electromechanical coupling helical gear transmission system for vehicles and solving the influence mechanism of crack evolution of helical gears on the dynamic characteristics of the electromechanical coupling helical gear transmission system for vehicles; the beneficial effect is that this invention establishes a nonlinear fault dynamic model of the electromechanical coupling transmission system for new energy vehicles, which is of great significance for the design, optimization and life prediction of the helical gear transmission system for new energy vehicles.

The invention discloses a large-tonnage insulating pull rod joint adhesive and a preparation method thereof, belongs to the technical field of high-voltage insulating materials, and aims to solve the technical problems that an existing large-tonnage insulating pull rod joint adhesive easily generates microcracks and interface layering under long-term electromechanical coupling stress and is difficult to early warn and self-repair. The preparation method comprises the following steps: firstly, synthesizing a polyurea microcapsule containing fluorescent dye tetraphenyl ethylene (TPE), and accurately controlling the wall thickness of the microcapsule through an interfacial polymerization technology to ensure that the microcapsule is broken under specified stress; then, the microcapsules are compounded with bisphenol A epoxy resin, nano montmorillonite and a silane coupling agent, and a curing agent is added to prepare an adhesive; when the adhesive joint is subjected to critical stress, the microcapsule is broken and the fluorescent dye is released, so that damage self-diagnosis is realized; the damage detection sensitivity, the mechanical property and the high temperature resistance of the adhesive are remarkably improved, and a reliable guarantee is provided for hot-line work of ultra-high voltage transmission lines.

Provided in the present application is an integrated device based on a third-generation semiconductor, and a manufacturing method therefor. The integrated device at least comprises an SiC substrate, a buffer layer, a GaN thin film layer and a piezoelectric material layer, wherein the SiC substrate comprises a first buffer layer stacked on a first SiC substrate and a second buffer layer stacked on a second SiC substrate; the GaN thin film layer at least comprises a first GaN thin film layer stacked on the first buffer layer and a second GaN thin film layer stacked on the second buffer layer; and the first SiC substrate, the first buffer layer, the first GaN thin film layer and the piezoelectric material layer which are stacked are used for forming a multilayer piezoelectric film, and the multilayer piezoelectric film is used for forming an SAW filter. The integrated device prepared by using the technical solution of the present application has a simple structure, greatly reduces the processing cost, can optimize the performance of SAW filters, significantly increases the use frequency of SAWs, and improves the electromechanical coupling coefficients of the SAW filters.

A ship diesel generating set single shafting torsional vibration analysis model and a modeling method thereof belong to the field of vibration and noise reduction of ship equipment, and comprise a diesel engine speed regulation system model, a diesel engine acting model, a diesel engine torque synthesis model and an electromechanical coupling analysis model established among flexible shafting models based on transmission shaft rotating speed signals; establishing a power grid coupling analysis model among the generator model, the excitation system model and the load system model based on voltage and current signals; all the models are coupled based on the electromechanical coupling analysis model and the power grid coupling analysis model, and a shaft system torsional vibration analysis model of the ship diesel generator set single-machine control system and shaft system torsional vibration is obtained. According to the application, the coupling effect analysis of the single-machine speed regulation control system, the generator excitation system, the power grid load system and the shaft system torsional vibration system of the ship diesel generating set in the island mode can be realized, the single-machine stable transient vibration characteristics of the ship diesel generating set can be conveniently researched, and support is provided for the design optimization of related system parameters.

Apparatus for near-field wireless energy transfer. A first layer provides or comprises a piezoelectric phase or a material with or adapted for electromechanical coupling; and a second layer provides or comprises a magnetostrictive phase or a material with or adapted for a magnetomechanical coupling. The second layer is mechanically and / or chemically coupled to the first layer to provide a composite structure.

The invention relates to the technical field of semiconductors, in particular to a surface acoustic wave resonance device, which comprises a substrate comprising a piezoelectric layer; the interdigital electrode is located on the piezoelectric layer, and the interdigital electrode sequentially comprises a first bus, a first gap part, an overlapping part, a second gap part and a second bus in the first direction; the piezoelectric layer sequentially comprises a first part, a first failure part, an effective part, a second failure part and a second part in the first direction, and the electromechanical coupling effect of the effective part is effective; the first bus is located on the first portion, the first gap portion is located on the first failure portion, the overlapping portion is located on the effective portion, the second gap portion is located on the second failure portion, and the second bus is located on the second portion. On the premise of not obviously influencing insertion loss, power tolerance and chip size, high-order nonlinearity, such as cubic nonlinearity, caused by electromechanical coupling outside a resonance area is effectively inhibited. In addition, the failure part extends to the bus, so that gap mode can be effectively inhibited.