852 results about "Mathematical model" patented technology

This invention provides a method and system for detecting impurities in flunarizine hydrochloride raw material. The detection method includes: acquiring the original chromatographic signal, performing empirical mode decomposition for denoising and baseline optimization to obtain a baseline-corrected and denoised chromatogram; determining the signal-to-noise ratio based on the energy relationship between noise and signal in preprocessing, determining the optimal analytical scale through a preset function, determining the number of chromatographic peak components by screening ridges through continuous wavelet transform, and extracting initial model parameters; establishing a mathematical model for the convolution of a standard Gaussian function and a modified Logistic distribution function for each component peak, using a trust-region reflection algorithm for nonlinear iterative fitting, with the objective function containing a least-squares residual term and a weighted regularization term; after the objective function converges, obtaining the optimal model parameters, and calculating the integral area of ​​each impurity component peak to determine its content.

This invention discloses a modeling method for a proxy model of a permanent magnet synchronous motor under eccentric conditions. First, a mathematical model of the eccentric motor proxy model is established, including the permanent magnet flux linkage and no-load back EMF, flux linkage model, voltage model, electromagnetic torque, and torque balance equations. Then, no-load back EMF, permanent magnet flux linkage, and dq-axis inductance data are obtained through finite element simulation, and harmonic fitting is performed on the permanent magnet flux linkage. Next, a multi-dimensional parameterized lookup table covering eccentricity type and degree, speed, torque, and rotor position angle is constructed. The lookup table and interpolation algorithm are integrated into the simulation platform to form a high-fidelity proxy model module that can be called in real time. Finally, the model accuracy is verified by comparison with finite element simulation and experimental data. This invention achieves high-precision and rapid mapping of the electromagnetic characteristics of eccentric motors, balancing modeling accuracy, efficiency, and versatility.

This application discloses a path planning method, apparatus, medium, and product for an aircraft traction system in confined spaces, relating to the field of aircraft path planning technology. The method includes: establishing a kinematic model of the aircraft traction system located in a hangar; constructing a path planning mathematical model based on the kinematic model; employing an improved hybrid algorithm to perform path search on the aircraft traction system based on the path planning mathematical model to obtain the target path of the aircraft traction system; the improved hybrid algorithm is derived from a hybrid algorithm, and the improvements include: using RS curves for bidirectional node expansion; setting the cost function to include the cumulative historical cost from the starting node to the current node and the heuristic cost from the current node to the target node; and establishing a closed table distinguishing between forward and backward directions. This application realizes path planning for an aircraft traction system in confined spaces.

The application provides a voltage imbalance treatment method and system for a micro-grid black start process under an unbalanced load, comprising the following steps: S1, determining that the focus point for treating voltage imbalance of a three-phase three-wire inverter is to eliminate negative sequence voltage; S2, introducing a mathematical model describing a two times power frequency oscillation disturbance signal characteristic generated by the negative sequence voltage into a control loop; and S3, using a proportional integral control method combined with a quasi-resonant controller to suppress the two times power frequency oscillation component in the control loop, so as to realize negative sequence voltage suppression and voltage imbalance treatment. The application analyzes the mechanism of voltage imbalance problems of the three-phase three-wire inverter under various unbalanced loads, and reveals that the focus point for treating voltage imbalance problems is to eliminate negative sequence voltage.

The application discloses a kind of offshore wind turbine pitch control methods based on predefined time adaptive dynamic programming, comprising: establishing single-pile offshore wind power generator full coupling mathematical model;The single-pile offshore wind power generator full coupling mathematical model includes the motion equation of system and the mathematical model of double-mass transmission system;Using the mathematical model of double-mass transmission system constructs rotor speed tracking error, adopts error adjustment method to process the non-affine characteristic of system, obtains the nonlinear affine model of single-pile offshore wind power generation system in combination with motion equation;The control strategy is constructed as the infinite time domain optimal performance index function of the change of pitch angle;Using predefined time nonlinear disturbance estimator estimates disturbance term in nonlinear affine model;To the equivalent form of Hamilton-Jacobi-Bellman equation of infinite time domain optimal performance index function, the approximate optimal control method based on only evaluation type neural network is used to solve equation to obtain optimal control strategy.

This disclosure relates to the field of petroleum exploration and development technology, and in particular to a method and system for determining bottom water intrusion characteristics. The method includes: determining the water permeability and the correlation coefficients between the matrix and fractures in a target block of a fractured sandstone gas reservoir; establishing and solving a mathematical model for cylindrical bottom water intrusion in a single well of the fractured sandstone gas reservoir based on the determined water permeability and the correlation coefficients between the matrix and fractures, obtaining a pressure function representing the difference between the original water pressure and the pressure at any point within the gas reservoir; using the obtained pressure function, determining the dimensionless bottom water intrusion volume; and determining the cylindrical bottom water intrusion characteristics of the dimensionless bottom water intrusion volume with respect to dimensionless time based on the determined dimensionless bottom water intrusion volume. By establishing a mathematical model of bottom water intrusion and calculating the cumulative water intrusion volume, the bottom water intrusion characteristics are determined, enabling an understanding of the entire dynamic process of bottom water intrusion in the reservoir.

This invention relates to a low-current harmonic direct torque control method for a dual three-phase permanent magnet synchronous motor (PMSM), belonging to the field of PMSM control technology. The method is as follows: S1: Establish mathematical models of the fundamental and harmonic subspaces of the dual three-phase PMSM under vector space decoupling, and clarify the voltage vector distribution characteristics of the two subspaces; S2: In the fundamental subspace, design a duty cycle modulation strategy based on the principle of minimizing the error vector, and an improved deadbeat flux linkage torque controller; S3: In the harmonic subspace, design an online learning harmonic canceller, using the least mean square algorithm to update the weight coefficients in real time; S4: Select the D1 vector set as the effective vector of the harmonic subspace and perform sector division; S5: Add the effective voltage vector action time of the fundamental and harmonic subspaces to generate the final switching sequence, which is output to the dual three-phase inverter to effectively suppress torque ripple and harmonic current of the dual three-phase PMSM.

The present application relates to a kind of fracturing fluid flowback period gas well productivity evaluation method, steps are as follows: obtaining gas component, and the relationship curve of pressure and gas density, gas viscosity is calculated to obtain;The ratio of water phase and gas phase relative permeability is calculated, and the relationship curve of pressure and gas phase relative permeability, water phase relative permeability is respectively interpolated to obtain;The relationship curve of pressure and pseudo pressure is obtained;Fracturing fluid flowback period water-gas ratio and bottom hole flowing pressure are calculated, and based on the relationship curve of pressure and pseudo pressure, pseudo pressure under gas reservoir pressure and bottom hole flowing pressure is respectively calculated by interpolation, and the total flow of gas and water is calculated, then the average of test point is calculated;Bottom hole flowing pressure and water-gas ratio are set, pseudo pressure under the set bottom hole flowing pressure is calculated, and combined with average, the open flow capacity of gas well is obtained.The present application establishes gas-water two-phase seepage under gas well productivity calculation mathematical model, realizes the accurate calculation of gas well productivity under gas-water two same production condition.

This invention relates to a method, apparatus, device, and medium for error compensation in a dual-drive feed system, belonging to the field of CNC equipment error measurement and compensation technology. The method includes: establishing a low-order volume array of the equipment to be modeled, equipped with a dual-drive feed system; obtaining an error transmission chain from the workpiece to the tool based on the low-order volume array; establishing a mathematical model of tool error and dual-axis error when the dual axes of the dual-drive feed system drive the tool; determining the homogeneous coordinate transformation matrix between any two volumes in the low-order volume array; establishing an error transmission matrix from the workpiece coordinate system to the tool coordinate system based on the error transmission chain, mathematical model, and homogeneous coordinate transformation matrix; establishing a comprehensive error model of the dual-drive feed system based on the error transmission matrix and the transmission matrix under ideal conditions; and performing error compensation on the dual-drive feed system based on the comprehensive error model, thereby improving the error compensation accuracy of the dual-drive feed system.

This invention discloses a method for calculating the flow rate of a single compressor in a continuous wind tunnel parallel compressor system, relating to the field of supersonic wind tunnel operation and commissioning. The invention uses the mass flow rate of the wind tunnel nozzle as a benchmark for the total flow rate; pre-determines the constant-speed total pressure ratio performance curves of each individual compressor and parameterizes them into a continuous constant-speed total pressure ratio performance mathematical model; during wind tunnel operation, the rotational speed and total pressure ratio of each compressor are measured in real time, and the reduced flow rate is obtained by solving inverse functions or using iterative methods. The initial mass flow rate of each compressor is calculated by combining the inlet total pressure and inlet total temperature; finally, corrections are made based on the deviation between the nozzle mass flow rate and the sum of the initial mass flow rates of each compressor to obtain the actual mass flow rate of each compressor. This achieves accurate determination of the flow rate of each individual compressor in parallel operation, providing a guarantee for the establishment of the target flow field and operational safety in the wind tunnel test section.

This invention relates to the field of unconventional oil and gas development technology, and to a device and method for quantitatively evaluating the permeability enhancement caused by oxidative thermal stress in shale oil. The former includes a triaxial core holder housed within a constant-temperature chamber, and confining pressure injection system, oxidation medium injection system, detection medium injection system, gas collector, upstream storage tank, downstream storage tank, chromatograph, and acoustic emission sensor spaced apart outside the chamber. This application provides a dynamic multi-field coupled physical simulation system capable of simulating real formation conditions. By collecting pressure, product composition, acoustic signals, and nuclear magnetic resonance relaxation data, it utilizes a mathematical model for dynamic inversion of porosity and permeability using the pressure pulse attenuation method. It integrates acoustic emission RA-AF source identification and nuclear magnetic resonance fractal evaluation to analyze the multi-field coupling effects of thermal, flow, force, and chemical fields generated during air injection, and quantitatively evaluates the degree of improvement in shale permeability and pore structure caused by oxidative expansion.

The application provides a unit quaternion-based error compensation calibration method, comprising the following steps: S11, establishing a calibration measurement system; S12, CCD camera calibration; S13, initial light plane calibration; S14, angle correlation establishment; S15, initial rotating shaft linear equation calibration; S16, assembly error compensation and rotating shaft optimization; and S17, dynamic light plane calibration. The application directly takes the rotating shaft of the motor of the galvanometer as a reference, calibrates the origin of the galvanometer linear laser three-dimensional measurement system on the rotating shaft of the motor of the galvanometer, does not need to add an additional coordinate system, reduces the conversion error of the coordinate system, does not need an additional work platform, can not consider the assembly error of the target plane and the workbench, and the calibration based on the unit quaternion can effectively reduce the complexity of the mathematical model and improve the calibration efficiency.

The application discloses a ship deployment and refueling joint optimization method considering multiple uncertainties. The method firstly constructs a nonlinear mixed integer programming deterministic model with the minimum total cost as the target, then introduces random oil prices and berthing times, constructs a robust optimization model containing an uncertainty set, and integrates the two to form a two-stage robust optimization model. The robust optimal ship deployment scheme and fuel injection strategy are obtained by iteratively solving the model through a Benders decomposition algorithm embedded with a branch and bound algorithm. The application constructs an integrated joint decision framework, simultaneously optimizes the ship deployment and fuel management in a unified mathematical model, captures and utilizes the internal relationship between different decisions, avoids the potential huge cost caused by separate decisions, fully considers the influence of the uncertainty of oil prices and port berthing times, makes the decisions have good risk hedging characteristics, fundamentally improves the scientificity and economy of the decisions, and effectively reduces the comprehensive cost of operation.

The application discloses a water heater constant temperature control method and device and a water heater, and relates to the technical field of water heaters, and in particular relates to a water heater constant temperature control method, a water heater constant temperature control device and a water heater. The method comprises the following steps: acquiring an operation parameter of the water heater; determining a real-time power theoretical value at a sampling time according to the operation parameter; establishing a water temperature control mathematical model based on the principle of energy conservation; determining a positional PID control model and a lag compensation model according to a water flow parameter and the water temperature control mathematical model; processing a temperature difference between a set temperature and an outlet water temperature based on the positional PID control model and the lag compensation model to obtain a power control output value; determining a target power value according to the power control output value and the real-time power theoretical value; and driving a heating module to perform heating according to the target power value. The application establishes a water temperature control mathematical model, deduces a PID control model and a lag compensation model, combines the PID control model and the lag compensation model with a real-time power theoretical value to obtain a target power value for heating, improves the stability and robustness of outlet water temperature, and shortens the response time.

The application provides a method and device for simulating a water delivery system of an impulse water turbine and electronic equipment, and the method comprises the following steps: establishing a mathematical model of the water delivery system of the impulse water turbine with variable step grids; dividing the water delivery pipe upstream of the distribution ring and the side pipe of the distribution ring into grids with the variable step grids; determining the boundary conditions of the inlet and outlet of the pipe based on the calculation working condition, and determining the initial flow and pressure values of each grid node according to the constant flow theory; combining the initial flow and pressure values of the grid nodes, iteratively calculating the corresponding flow and pressure values of each grid node at the current time, and determining the unit side parameters at the current time until the termination condition is met. Through the application, certain theoretical basis and technical support are provided for the safe and stable operation of the impulse unit, and the problem that the existing related technologies are difficult to balance the pipe calculation efficiency and the calculation accuracy is solved.

The present application relates to a kind of white plume removal energy-saving control method and system, belong to the device field of handling smoke and waste gas.By control module, the real-time change of air parameter is collected, using air saturation humidity database, air temperature-enthalpy / density calculation model, establish white plume removal system operating cost mathematical model.According to the constantly changing atmospheric conditions, slagging condition etc., with operating cost as optimization goal, determine the best exhaust point, the best operation combination, using numerical analysis to seek global optimal solution, make actual operation curve quickly approach optimal curve, to adjust air cooler fan frequency, then on the basis of not affecting white plume removal effect, maximize the energy consumption of white plume removal is reduced, and make actual operating cost minimum.

The invention discloses a field weakening trajectory tracking control method for permanent magnet synchronous motors based on enhanced model predictive current control, comprising: S1, establishing a mathematical model of the permanent magnet synchronous motor in a synchronous rotating coordinate system and determining the optimal operating trajectory in the field weakening region; S2, constructing an extended virtual voltage vector set synthesized from the basic voltage vector, and constructing a virtual voltage vector containing continuous components, excess components, and disturbance components as feedback quantities, which are adjusted by the field weakening current controller. d The shaft reference current limits the virtual voltage amplitude within the inverter output voltage limit; S3, a nonlinear extended state observer based on a nonlinear function is designed to estimate the current state and total disturbance in real time, and correct the current prediction model. The optimal voltage vector is selected through a cost function, and a switching pulse sequence is generated to drive the inverter. This invention can effectively reduce current ripple when motor parameters are mismatched and overcome the deviation of the field weakening trajectory when model parameters are mismatched.

This invention discloses a day-ahead scheduling optimization strategy for a microgrid system considering thermal and humidity load responses. The strategy includes: supplying energy to an air conditioning system via the microgrid system; the air conditioning system processing return air using reheat; obtaining the return air temperature and relative humidity by setting a range based on known indoor temperature and relative humidity; calculating the supply air temperature and relative humidity by establishing a thermal-humidity balance equation; obtaining the cooling capacity of the air conditioning system using the enthalpy difference between the return and supply air; and, based on the mathematical models of the main equipment in the microgrid system and the cooling capacity of the air conditioning system, minimizing the overall operating cost min C of the microgrid system by using a particle swarm optimization algorithm to obtain the optimal hourly output of the main equipment in the microgrid system. Compared to existing optimization strategies that only consider thermal load responses, this invention also incorporates humidity load responses, simultaneously implementing temperature and humidity control to improve load transfer capacity and system economic efficiency.

Systems and methods for mathematical modeling of the hardware and software stack of commodity computer platforms are provided, enabling provable guarantees on memory, device, and program execution. This approach addresses the technical problem of reliance on system agents that rely on implicit trust in the operating environment, which can be exploited by sophisticated attackers using complex threats such as memory access exploits and code / data integrity exploits. The solution provides a proactive, mathematically-backed security solution that eliminates entire classes of cyberattacks by design, ensuring realizable guarantees on commodity computer platforms running hardware and software stack elements at the lowest operating level. This approach has significant advantages over current reactive cybersecurity methods, including reduced complexity and overhead, and increased confidence in the integrity of the system. The solution's main uses include providing mathematically-backed security and availability guarantees for critical infrastructure, financial institutions, and other organizations vulnerable to cyberattacks.

The present application relates to the technical field of power system operation analysis and regulation, and specifically discloses a kind of VSC-HVDC system power flow regulation capability evaluation method, comprising the following steps: S1, the power flow regulation range mathematical model of establishing containing back-to-back flexible HVDC transmission system BTB;S2, establish new energy output uncertainty model;S3, construct power flow over-limit risk and risk adaptive power regulation mechanism;S4, generalized polynomial chaos matrix method is used to evaluate the two-way power flow regulation range;S5, output power flow regulation range evaluation results and visual index.The present application uses the above-mentioned VSC-HVDC system power flow regulation capability evaluation method, realizes the collaborative quantification of new energy randomness, operation risk and BTB regulation capacity, improves the accuracy and engineering practicability of the evaluation results, and provides a decision basis for power system planning and design, operation control.

In order to overcome the problem that the current technology is difficult to estimate and continuously correct the bridge twin model by obtaining a series of test and test data, the application provides a bridge twin dynamic model Fourier modeling method based on test data, which is only related to the parameters of the bridge according to the system matrix related to all nodes of the bridge and the observation coefficient matrix related to all nodes, and the first continuous test process of the bridge does not change greatly, and the first comprehensive detection of the bridge twin dynamic mathematical model and the subsequent each time of the bridge twin dynamic mathematical model comprehensive correction process is relatively short, according to the characteristics of the fast and slow change matrix, the slow change matrix is set as a constant matrix in the first continuous test, and the system matrix related to all nodes of the bridge and the observation coefficient matrix related to all nodes in the bridge twin model are established through a series of effective tests and optimal indexes, and the bridge twin model is continuously corrected in the whole life cycle of the bridge, so that the technical problem of estimating and improving the bridge vibration model by obtaining a series of test and test data is solved.

A design method for a multi-point flexible displacement sensor, characterized in that the method comprises the following steps: designing a multi-point flexible displacement sensor structure, establishing a displacement sensing mathematical model of the sensor, carrying out a sensor calibration test, applying the calibrated sensor to soil shear deformation measurement. Compared with the prior art, the beneficial effects of the invention are as follows: The multi-point flexible displacement sensor designed in the invention has a small size and low flexural rigidity. After being embedded in soil, it can deform coordinately with the soil, effectively avoiding disturbance to the soil. In combination with a distributed monitoring network, multi-point synchronous monitoring is realized.

This invention discloses a magnetotelluric denoising method and system based on a physics-driven and conditional diffusion model, belonging to the field of electromagnetic signal processing technology. This method integrates the advantages of neural networks and the physical characteristics of magnetotelluric signals, and proposes a physics-driven synthesis strategy based on statistical priors of measured source data and a curriculum-based dynamic physics-driven noise addition strategy based on training progress factors. Addressing the scarcity of high-quality, clean samples, a clean background field that highly approximates real physical characteristics is synthesized using a parametric mathematical model. The introduction of curriculum-based dynamic physics-driven noise addition (such as noise floor annealing, square wave incrementing, and morphological clustering pulses) accurately simulates natural background degradation and complex human interference, enabling the model to adapt to extremely complex time-frequency characteristics under different geological structural backgrounds. This completely overcomes the domain shift problem caused by static Gaussian white noise training, constructs a richer sample library, and lays the foundation for accurate denoising of conditional diffusion models.

This invention discloses a sensor-integrated multi-UAV beam trajectory design method for anti-UAV operations. First, a system model is constructed, defining the channel model, signal model, and power consumption model. Then, a mathematical model of the long-term Cramer-Rao bound (CRB) minimization problem is established, and the optimization problem is reconstructed, addressing uncertainties in the optimization objective. Next, the problem is broken down into three sub-problems: joint optimization of transmit and receive beams, joint optimization of user association and UAV scheduling, and UAV trajectory optimization. These sub-problems are solved using Lagrange relaxation, semi-definite relaxation, and penalized successive convex approximation methods, respectively. Finally, an alternating iterative strategy is used to coordinate the solutions to these sub-problems. This invention solves problems in existing technologies such as incomplete coverage, poor sensing performance, signal interference, and positional uncertainty caused by UAV maneuvers, improving cooperative sensing performance and meeting the dual requirements of flexible sensing and reliable positioning.

The application provides a KDP crystal surface micro-nano defect DPN water-soluble repair morphology evolution simulation method, and relates to the technical field of micro-nano manufacturing, and aims to solve the problem that there is no quantitative method to simulate the evolution process of the KDP crystal surface micro-nano defect DPN water-soluble repair morphology in the prior art. The method comprises the following steps: step one, constructing a defect local growth mathematical model; step two, performing dimension conversion on the defect depth information, and performing dimension reduction processing on the model; step three, converting the defect local growth mathematical model into a standard partial differential equation form; step four, obtaining the initial value of the defect local growth mathematical model, and setting the model boundary condition; step five, performing parameterization scanning on the undetermined coefficient, and determining the undetermined coefficient value; and step six, simulating the KDP crystal surface micro-nano defect DPN water-soluble repair morphology evolution process. Through dimension conversion, the dimension reduction processing of the model is realized, and finally the simulation of the KDP crystal surface micro-nano defect DPN water-soluble repair morphology evolution process is realized.

The application discloses a high-pressure rotary jet pile diameter monitoring data processing method based on resistivity testing, and aims at solving the technical problems of geometric distortion caused by probe eccentricity, signal distortion caused by dynamic multiphase flow environment, and contradiction between ideal mathematical model and real irregular shape in the prior art.The technical scheme is as follows: original resistivity sequence is subjected to statistical denoising, outlier bad points are removed, and characteristic true values are extracted; the characteristic true values are corrected to equivalent centered resistances and the equivalent radii are inversely calculated through iterative solution based on the eccentric electric field analytical relationship; the micro disturbance of the characteristic true values in the depth direction is analyzed to extract irregularity operators, the circumferential radius distribution of the reinforced body section is reconstructed based on the energy equivalent constraint, and the minimum effective envelope radius and the maximum diffusion envelope radius are determined.The application realizes accurate conversion from discrete electrical sampling to high-fidelity geometric profile, and effectively solves the industry pain point that necking defects are easily covered by eccentric effect.

The application discloses a reconfigurable metasurface-based antenna design method and device, equipment and a storage medium. The method comprises the following steps: constructing a mathematical model according to the relationship between antenna structure parameters and gain; solving the mathematical model to obtain initial antenna structure parameters when the system gain is maximum; and performing parameter scanning in the preset range of the initial antenna structure parameters through full-wave simulation to obtain optimized antenna structure parameters. According to the reconfigurable metasurface-based antenna design method provided in the application, the structure of the reconfigurable metasurface antenna can be quickly optimized, the time required for optimization is reduced, good performance is achieved, and the optimization effect is guaranteed.

This invention relates to the field of cooperative control technology, specifically to an adaptive event-triggered fixed-time consistency control method for multi-agent systems, comprising the following steps: S1, constructing a mathematical model of a nonlinear high-order multi-agent system with uncertain dynamics; S2, constructing a Lyapunov function containing a lower bound of uncertain parameters based on coordinate transformation; S3, designing an adaptive event-triggered controller with a positive bounded function using a backstepping control method, including a virtual controller, an adaptive law, and an event triggering mechanism; S4, proving through stability analysis that a high-order nonlinear multi-agent system with uncertain dynamics can achieve consistent output at a fixed time and avoid Zeno behavior. This invention's adaptive event-triggered fixed-time consistency control method for multi-agent systems solves the problem of consistent output at a fixed time for a class of high-order nonlinear multi-agent systems and extends existing results on consistent output at a fixed time.