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33results about How to "Calculation stable" patented technology

Seven-degree-of-freedom mechanical arm inverse kinematics solving method, system and equipment based on numerical iteration

The invention discloses a seven-degree-of-freedom mechanical arm inverse kinematics solving method, system and device based on numerical iteration. The method comprises the steps that S1, a D-H kinematics model of a mechanical arm is established based on a joint configuration of the seven-degree-of-freedom mechanical arm; s2, calculating a Jacobian matrix according to the joint angle sequence; s3, introducing a weight matrix to suppress the joint speed at the edge of the joint range; s4, introducing a damping factor, and calculating to obtain an optimized Jacobian pseudo-inverse matrix; s5, the pose error between the expected tail end pose and the current tail end pose of the tail end actuator of the mechanical arm is calculated; s6, converting the pose error into a joint angle adjustment amount by using the optimized Jacobian pseudo-inverse matrix to obtain a joint angle iterative formula; and S7, based on the pose error, the joint angle of each rotating joint of the mechanical arm is determined through a numerical iteration method. According to the method, the problem of unstable solution of a traditional analytical method under the singular configuration can be avoided, and the calculation efficiency and the numerical stability are improved.
Owner:SOUTH CHINA UNIV OF TECH

Intelligent inflation algorithm applied to upper arm type upper air sphygmomanometer

The invention relates to an intelligent inflation algorithm applied to an upper arm type upper-air sphygmomanometer, which comprises the following steps of: 1, after the sphygmomanometer enters a measurement state, acquiring and processing a pressure value signal by a central processing unit; 2, eliminating the interference of the pulse wave signal on the inflation slope through a filtering algorithm; 3, after the central processing unit obtains data from the pressure sensor, the increasing slope of the pressure value in the cuff is calculated at fixed time intervals; 4, after the slope is obtained through calculation, the slope is compared with a set target slope, and the inflation rate of the inflator pump is adjusted according to the slope difference degree. The low-pass filter is strong in denoising capability, can effectively filter high-frequency noise and a part with rapid data change, enables signals to be clear and reliable, and can reduce the influence and ensure the stability of inflation slope calculation due to the fact that pulse waves are coupled with noise signals generated by an inflation pump in the inflation process.
Owner:HONSUN NANTONG

Overvoltage protection circuit of switching power supply and switching power supply

The invention discloses an overvoltage protection circuit of a switching power supply and the switching power supply. The switching power supply generates an output voltage according to an input voltage through periodic connection and disconnection of a main power tube. The overvoltage protection circuit comprises a voltage sampling unit which samples node voltage on a sampling node of the switching power supply to obtain node sampling voltage, and the node voltage is the sum of the product of output voltage and coefficient and input voltage; and the overvoltage control unit is used for performing overvoltage protection on the switching power supply according to the conduction duty ratio, the node sampling voltage and the characterization voltage of the overvoltage protection threshold. According to the overvoltage protection method, a proper sampling point is selected to enable the sampling voltage to be related to the output voltage and the input voltage at the same time, then the node voltage is sampled to calculate the output voltage, overvoltage protection is performed, sampling is simple, the calculated amount is small, errors are small, the overvoltage protection effect is good, an auxiliary winding is not needed, and the system cost is low.
Owner:JOULWATT TECH INC LTD

Method and system for improving seismic inversion resolution through reflection coefficient protection

The invention provides a method and system for improving seismic inversion resolution through reflection coefficient protection, and belongs to the technical field of oil-gas exploration. The method comprises the steps that seismic pure wave data, interval transit time, a density logging curve and target layer position data of a work area are acquired; building an earthquake model by utilizing the multi-well comprehensive wavelet extracted from the target work area and three adjacent earthquake channels of the earthquake pure wave data; inverting a reflection coefficient value by using a multi-task relevance vector machine Bayesian machine learning algorithm; establishing an impedance low-frequency model of a target layer by using a logging impedance curve of a target layer series of the target work area, and performing channel integration and low-frequency compensation on a reflection coefficient to obtain a high-resolution impedance inversion result; and thin dessert body tracking and reservoir quantitative depiction. According to the method, the signal-to-noise ratio of the inversion reflection coefficient is high, the weak reflection coefficient of the thin layer is well protected, particularly, the resolution ratio of the inversion result is far higher than that of an original earthquake, and the recognition effect on the shale oil thin dessert is good.
Owner:PETROCHINA CO LTD

Bezier curve calculation method and device, medium and program product

The invention relates to the technical field of algorithm calculation, in particular to a Bezier curve calculation method and device, a medium and a program product. The Bezier curve calculation method comprises the steps that an initial graph is provided, and a plurality of initial control points of a Bezier curve are obtained based on the outline of the initial graph; performing uniform processing on the initial control point to obtain a plurality of uniform target control points; performing recursive calculation on the target control point to obtain a new control point of the Bezier curve; and obtaining a target Bezier curve by taking the target control point and all new control points obtained in the recursive calculation process as final control points. The contour points of the Bezier curve are calculated through multi-thread cooperation, and the calculation efficiency is improved.
Owner:SHENZHEN JINGYUAN INFORMATION TECH CO LTD

A storm surge floodplain algorithm and device based on SCVT unstructured grid

A storm surge floodplain algorithm and device based on SCVT unstructured grid, the method performs grid division and numbering according to the SCVT unstructured grid; respectively determines the indexing strategy of the adjacent grid cells of the grid cell, the grid edge corresponding to the grid cell, and the two adjacent grid cells of the grid edge; defines the model physical variables and sets the corresponding marking positions; when the numerical mode is initialized, the grid cell and the grid edge are respectively marked for dry and wet states; the numerical mode is integrated according to the set time step, and after the integration is completed in one step, the dry and wet change state of the grid cell is judged and marked by the dry-to-wet strategy and the wet-to-dry strategy, and the numerical mode integration is circulated within the set simulation time until the simulation ends, and the final dry and wet state of the grid cells in the simulation area and the floodplain inundation depth and other information are output. The floodplain algorithm designed by the present invention is based on the SCVT grid, has a local encryption function, and the calculation is more stable, and is more suitable for storm surge floodplain simulation.
Owner:NAT MARINE ENVIRONMENTAL FORECASTING CENT

Earthquake landslide large deformation whole process simulation method based on grid isolation technology

ActiveCN122020818AAchieve real physical reproductionEliminate wave reflection interferenceGeometric CADDesign optimisation/simulationLandslideStructural engineering
The invention discloses an earthquake landslide large deformation whole process simulation method based on a grid isolation technology, and relates to the technical field of geotechnical engineering. According to the method, a separated background grid containing a safety isolation belt and a multi-medium model are constructed based on a second-order convective particle domain interpolation material point method, and dynamic analysis is performed on seismic landslide by using a strain-driven soft and hard coupling constitutive mechanism, so that flexible input of seismic waves at the isolation belt and drifting prevention of a substrate are realized; and the complete evolution process of the landslide from undrained shear crack initiation to large-deformation friction accumulation can be accurately simulated. According to the method, wave reflection interference of a dynamic boundary and numerical drift of long-lasting integral are effectively eliminated, and real physical reproduction of the whole process of seismic landslide from crack initiation to friction accumulation is realized; therefore, calculation of large deformation and permanent displacement of the side slope under the earthquake action is more accurate and stable, and a foundation is laid for prediction and evaluation of the whole evolution process of landslide disasters.
Owner:SOUTHWEST JIAOTONG UNIV

Electric power carbon emission flow looped network topology calculation method and system

The invention discloses an electric power carbon emission flow looped network topology calculation method and system. The method comprises the following steps: acquiring a data file; the content of the data file comprises a static archive data section, a topological information data section and an operation power data section; carrying out database storage on the data file; data integration is performed on the warehousing data, and two loop problems, namely a two-station multi-loop carbon flow route scene and a single-loop carbon flow route scene, are solved by comparing the integrated data; the endless loop in the carbon flow calculation process can be effectively avoided, and the stability and accuracy of the calculation process are ensured. And through loop processing, the carbon flow calculation does not have an endless loop.
Owner:DALIAN POWER SUPPLY COMPANY STATE GRID LIAONING ELECTRIC POWER

Ffr determination method and apparatus based on multi-modal medical image, device, and medium

PendingEP4403092A4improve accuracyCalculation stableImage enhancementImage analysis
The present invention provides an FFR determination method and apparatus based on multi-modal medical image, a device, and a medium. The method includes: obtaining an intravascular image comprising a blood vessel segment of interest; obtaining an extravascular image comprising a blood vessel segment to be detected, where the blood vessel segment to be detected at least partially coincides with the blood vessel segment of interest; performing registration on the intravascular image and the extravascular image to obtain a registration result; and determining a target fractional flow reserve based on multi-modal medical image by using the registration result on the basis of the intravascular image and the extravascular image. In the FFR determination method of the present invention, calculation of the fractional flow reserve is optimized by utilizing the registration result of the intravascular image and the extravascular image and integrating advantageous information of the intravascular image and the extravascular image, so as to obtain the fractional flow reserve which is based on multi-modal medical image and has both blood vessel segment integrity and local accuracy, thereby improving the accuracy and stability of fractional flow reserve calculation.
Owner:SUZHOU PULSE RONGYING MEDICAL TECH CO LTD

In-service material performance detection system based on indentation method

InactiveCN122084427AAchieving direct decouplingThe identification process is straightforward and universalDesign optimisation/simulationInvestigating material hardnessMicron scaleSite evaluation
The invention relates to the field of material mechanical property testing, and provides an in-service material property detection system based on an indentation method, comprising: an excitation module for applying a composite dynamic excitation load to a pressure head when the spherical pressure head is pressed into a to-be-detected material; the signal acquisition module is used for synchronously acquiring a dynamic load signal and a dynamic displacement signal in the pressing-in process of the pressing head; the data processing module is used for calculating an instantaneous phase difference according to the dynamic load signal and the dynamic displacement signal, constructing an evolution curve of the instantaneous phase difference along with the change of the pressure depth, and extracting a first characteristic depth, a second characteristic depth and a phase hardening index from the evolution curve; and the performance resolving module is used for calculating the elastic modulus and the yield strength of the to-be-tested material according to the first characteristic depth, the second characteristic depth, the phase hardening index and the mapping relation model. According to the method, the plastic hardening constitutive relation of the material does not need to be preset, rapid and micro-damage detection of the tensile property of the material can be achieved through single-time micron-order pressing-in, and the method is particularly suitable for field evaluation of in-service equipment.
Owner:XIAN THERMAL POWER RES INST CO LTD +1

A method for constructing monomial basis functions of discontinuous finite elements applicable to arbitrary meshes

ActiveCN118446056BCalculation stableMain diagonalEngineering
The present invention provides a method for constructing a discontinuous finite element monomial basis function applicable to any grid, belongs to the field of computer-aided engineering, and is used for hybrid grid calculations. The present invention divides the calculation area into a plurality of unstructured grids to maximize the filling of the calculation area. The expressions of the basis functions are consistent for different units and can be directly used for the discontinuous finite element method on the unstructured hybrid grid. The diagonal part of the mass matrix of the basis function space is 1, and the absolute value of the non-diagonal part is less than 1, which satisfies the main diagonal dominance and makes the calculation more stable; the basis function is defined in global coordinates, and when calculating the gradient, it is not necessary to use the Jacobian matrix of the unit isoparametric transformation, which is more direct and efficient.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA

Driving motor temperature calculation method based on temperature-fluid weak coupling technology

The invention discloses a driving motor temperature calculation method based on a temperature-fluid weak coupling technology. The problem of motor heat network calculation oscillation caused by transient rapid heat exchange between fluid and a motor winding and an iron core component is solved. According to the method, heat network capacitance matrix characteristics are deeply analyzed, the influence of the ratio of the maximum value and the minimum value of matrix elements on iterative calculation convergence is considered, and a certain short time period is considered, the motor cooling fluid is driven, the temperature change of the motor is small, and the internal heat transfer phenomenon is stable; according to the method, a weak coupling calculation method of a rapid change fluid field and a slow change motor internal temperature field is established, different calculation frequencies are adopted in the fluid field and the temperature field, the inherent defect that the ratio of the maximum value to the minimum value of a heat capacity matrix element is too large is overcome, and rapid and stable calculation of the temperature of the driving motor is achieved. The temperature calculation method is clear in thought and easy to operate, has the advantages of being easy to implement, rapid in calculation, universal and the like, and shows excellent performance.
Owner:SOUTHEAST UNIV

Transient accompanying-based radiator flow channel topological optimization method and system

The invention discloses a radiator flow channel topological optimization method and system based on transient accompanying, and the method comprises the steps: carrying out the optimization of an optimization problem of a radiator flow channel; constructing and solving a transient NS equation on the basis of an optimization column formula, solving the transient NS equation by taking design variable distribution, boundary conditions and initial conditions as inputs and taking a PIMPLE algorithm in OpenFOAM as a discrete method, and performing stepping on forward time to obtain physical fields under different time steps; solving an adjoint differential equation of the transient NS equation by using a PIMPILE algorithm to obtain adjoint variable information and sensitivity information under different time steps; performing optimization solution by applying a moving asymptote method MMA to obtain new design variable distribution and a target function; and carrying out residual calculation on the new design variable distribution and the target function and a previous calculation result, comparing with a convergence index to judge whether a convergence condition is reached, and if the convergence condition is reached, ending optimization.
Owner:XI AN JIAOTONG UNIV +1

Water diffusion-mechanical coupling calculation method based on particle DDA

The invention discloses a moisture diffusion-mechanical coupling calculation method based on particle DDA, and the method specifically comprises the steps: carrying out the discretization of a to-be-solved region through the particle DDA, and endowing a control parameter; contact retrieval is carried out between the particles and between the particles and the boundary, the action ranges of mechanics and moisture diffusion are determined, and a force chain and a virtual moisture diffusion channel are established between the action ranges; calculating the mechanical part of the DDA of the particles, and updating the position information of the particles; assembling a moisture diffusion equation set of the particle DDA, solving the equation set and updating particle moisture content information. According to the moisture diffusion-mechanical coupling calculation method based on the particle DDA, an implicit solution strategy is adopted, the time step is large, and calculation is stable; and the influence of cracks on the moisture diffusion process can be fully considered. Benefited from the improvement, the constructed water diffusion model not only improves the calculation efficiency and simplifies the material parameter assignment process, but also can more accurately describe the water migration behavior in the crack-containing structure.
Owner:ZHONG MEI (E ER DUO SI SHI) NENG YUAN KE JI YOU XIAN ZE REN GONG SI +2

Substation inspection robot motion control optimization method and system based on deep learning

The invention discloses a power transformation inspection robot motion control optimization method and system based on deep learning, and the method comprises the steps: carrying out the diagnosis of the ill-conditioned condition of a normal matrix N0 based on the condition number of the normal matrix N0 in a loss function, carrying out the correction of the normal matrix through a Tikhonov regularization method, adjusting three minimum values in the feature values of the normal matrix, and carrying out the optimization of the motion control of a power transformation inspection robot. Obtaining a corrected normal matrix; constructing a path planning method and a reward function optimization method based on the corrected normal matrix, and designing neural network input and output based on deep learning; and motion optimization control of the power transformation inspection robot is realized. According to the method, the inspection robot can realize all-collision-free inspection point traversal path planning with the optimal path, and detailed reward and punishment evaluation is carried out on substation inspection tasks, collision trend, trend of approaching a new detection point, collision, reaching the new detection point, crossing the detection point, bypassing, timeout and the like.
Owner:GLOBAL ENERGY INTERCONNECTION RES INST CO LTD +1

Full-ring unsteady efficient numerical simulation method and system for multistage axial flow compressor

The invention relates to the technical field of computational fluid mechanics, in particular to a multi-stage axial flow compressor full-ring unsteady efficient numerical simulation method and system, and the multi-stage axial flow compressor full-ring unsteady efficient numerical simulation method comprises the following steps: performing steady calculation on a whole-stage single-channel grid flow field to obtain single-channel data of each stage; periodically copying the ith-level single-channel data into a full ring to obtain ith-level full-ring data; combining the ith-level full-ring data with downstream single-channel data of other levels, and performing unsteady calculation to obtain ith-level full-ring data information; periodically copying the (i + 1) th-level single-channel data into a full ring to obtain (i + 1) th-level full-ring data; (i + 1) th-level full-ring data is combined with downstream single-channel data of other levels, ith-level outlet full-ring-current field data serves as an (i + 1) th-level full-ring inlet boundary, and (i + 1) th-level full-ring data information is obtained through unsteady calculation; and obtaining all-ring data information in the rest single-channel periods in sequence, and combining the all-ring data information to obtain whole-level all-ring unsteady data.
Owner:XI AN JIAOTONG UNIV

A method and system for device monitoring for oil chromatography detection

The application discloses a kind of equipment monitoring method and system for oil chromatography detection, it is related to power equipment state monitoring technical field, the oil dissolved gas concentration data in the historical operation time of target equipment is collected and the operation condition data of corresponding moment;The oil dissolved gas concentration data and operation condition data collected are cleaned and pretreated, and structured data set is constructed;Based on structured data set, for each oil dissolved gas, the threshold prediction model of fusion operation condition data is constructed;Real-time operation condition data and oil dissolved gas concentration data of target equipment are collected, and the concentration threshold of each oil dissolved gas is obtained according to threshold prediction model;The oil dissolved gas concentration of each real-time acquisition is compared with corresponding concentration threshold, and the abnormal condition of oil dissolved gas is judged;The operation state of target equipment is judged according to the abnormal condition of oil dissolved gas.
Owner:JIANGSU JIUCHUANG ELECTRICAL S T

Active suppression method and system for closing excitation inrush current of train traction transformer

ActiveCN118801311BCalculation stableSuppresses inrush currentSpeed controllerRailway vehiclesVoltage amplitudeTraction transformer
The present application provides a method and system for actively suppressing the magnetizing inrush current of the train traction transformer during closing, wherein the method includes: stabilizing the intermediate DC voltage of the intermediate DC circuit of the train traction system according to the train running condition; constructing a three-phase phase-locked method using a second-order generalized integral to obtain the grid voltage frequency, phase and voltage amplitude; detecting the grid voltage, and when the grid voltage passes through zero, simultaneously starting the four-quadrant rectifier module of the train traction system, and adjusting the output of the four-quadrant rectifier module according to the grid voltage frequency, phase and voltage amplitude and the intermediate DC voltage, so that the primary voltage of the traction transformer of the train traction system is consistent with the grid voltage; detecting the current secondary component of the four-quadrant rectifier module, and when the current secondary component reaches a set value, closing the circuit breaker of the train traction system. The present application can effectively suppress the magnetizing inrush current generated when the circuit breaker is closed.
Owner:CRRC ZHUZHOU ELECTRIC LOCOMOTIVE RESEARCH INSTITUTE CO LTD

Fully automatic polyurethane foam machine for on-site patching

This utility model relates to the field of on-site repair of insulated pipes, specifically a fully automatic polyurethane foaming machine for on-site repair. The inlet ends of the black and white material tanks are connected to the outlet ends of the black and white material barrels via pipes II and I, respectively. The outlet ends are connected to the inlet ends of the black and white material switching unit via pipes VI and III, respectively. The inlet ends of the black and white material cylinders are also connected to the outlet ends of the black and white material switching unit via pipes V and IV, respectively. The inlet end of the mixing nozzle is connected to the white material switching unit and the black material switching unit via pipes VII and VII, respectively. The outlet end of the hydraulic station is connected to the outlet end of the mixing nozzle via pipe IX, and its inlet end is first connected to the outlet end of the mixing nozzle via pipe X, providing power for opening and closing the mixing nozzle. This utility model solves the problems of high difficulty in operation, low efficiency, and difficulty in guaranteeing quality in existing manual foaming machines for repair.
Owner:DALIAN KAIYUAN PIPELINE

A sound source three-dimensional positioning system and method based on binocular acoustic camera

ActiveCN121325104Baccurate calculationCalculation stable
The application relates to the technical field of sound source positioning, and discloses a sound source three-dimensional positioning system and method based on a binocular acoustic camera, wherein the positioning system comprises a first acoustic camera and a second acoustic camera, which are used for shooting the same sound source from different positions to obtain an acoustic image; an information processing system is in communication connection with the first acoustic camera and the second acoustic camera, is used for receiving and processing acoustic image data collected by the two acoustic cameras, and calculates the position coordinates of a sound source in a three-dimensional space based on the relative position relationship of the first acoustic camera and the second acoustic camera, a horizontal pixel path, a vertical pixel path and pixel coordinates of the sound source in the acoustic image of the first acoustic camera and the second acoustic camera. The application breaks through the limitation that a traditional single acoustic camera can only be two-dimensionally positioned, the acoustic images are collected by the two cameras from different positions, the information processing system constructs complete logic of multi-source data fusion-three-dimensional coordinate calculation, and a basic solution scheme is provided for complex three-dimensional space sound source positioning.
Owner:BEIJING INST OF AEROSPACE TESTING TECH

A tunnel lining concrete cracking mechanism analysis method based on a phase field method

PendingCN122508879Aautomatically sproutAutomatic scalability
This invention discloses a method for analyzing the cracking mechanism of tunnel lining concrete based on the phase-field method, including step one: establishing the theoretical control equation of phase-field fracture of tunnel lining; step two: constructing a geometric model of the tunnel lining-surrounding rock system; step three: obtaining the evolution process of displacement field and phase-field variable field; step four: revealing the cracking mechanism and key influencing factors; and step five: model verification and parameter sensitivity analysis. This invention, by establishing a phase-field fracture control equation coupled with multiple physics fields, can automatically and naturally simulate the initiation, propagation, and convergence of any complex cracks in the lining. By introducing a geometric and material model reflecting the microscopic heterogeneity of concrete, it reveals the regulation mechanism of aggregate distribution and weak interface zones on macroscopic cracking behavior at the tunnel scale. Through the coupled analysis of multiple fields such as mechanics, seepage, and temperature, the simulation environment is made closer to engineering reality.
Owner:CHANGJIANG RIVER SCI RES INST CHANGJIANG WATER RESOURCES COMMISSION

Simulation method for flow field of gas compressor

The invention relates to the technical field of gas compressors, in particular to a simulation method for a flow field of a gas compressor, which is characterized in that on the basis of an AUSM + format, input three dimensions are projected to one dimension, output one dimension is reversely projected to three dimensions, the one-dimensional format is successfully popularized to a three-dimensional relative coordinate system, the cross section flux is solved, and the flow field of the gas compressor is simulated. And a simulation calculation result of the gas compressor is obtained through calculation. Through the method, the problem of inaccurate shock wave calculation of gas compressor flow field simulation in the prior art can be solved.
Owner:DONGFANG ELECTRIC CHENGDU INTELLIGENT TECH CO LTD +2

Main hoist residual life prediction method and device

The present application relates to a kind of main hoist remaining life prediction method and device, wherein, method includes: S1, the vibration time series data and working condition parameter time series data of the main hoist to be measured are acquired, and the measured vibration signal and measured working condition parameter signal of single operation are segmented, detection data group is constructed and time information is generated;S2, using detection data group to identify working condition, input the first self-encoding model corresponding to working condition, obtain the vibration signal after reconstruction and physical constraint residual, and the model is based on physical constraint dynamics equation to build;S3, total deviation is calculated according to reconstructed signal and physical constraint residual, and deviation sequence is obtained according to time sequence;S4, failure curve is generated based on deviation sequence, and then the remaining life is obtained.The present application can effectively separate working condition influence, fusion physical priori knowledge, realize accurate and reliable life prediction under the condition of variable working condition and variable load.
Owner:SHANGHAI MOONS AUTOMATION CONTROL CO LTD

Three-dimensional target detection system based on two-dimensional perception

The invention discloses a three-dimensional target detection system based on two-dimensional perception. The three-dimensional target detection system comprises a two-dimensional perception module, a three-dimensional coordinate acquisition module and a post-processing module, the two-dimensional sensing module is used for performing feature extraction and region detection on an input image based on a deep learning target detection and key point detection algorithm, and outputting a bounding box of a to-be-detected target and two-dimensional coordinates of a plurality of key points; the three-dimensional coordinate acquisition module is used for performing spatial mapping on the two-dimensional coordinates of the plurality of key points and depth data acquired by the depth sensor, and calculating the three-dimensional coordinates of the key points; and the post-processing module is used for performing space consistency optimization on the three-dimensional coordinates of the key points in combination with the structure prior of the to-be-detected target, and calculating the pose of the to-be-detected target. According to the method, the high-precision three-dimensional pose of the to-be-measured target can be directly calculated from the two-dimensional visual information and the depth data without depending on complex three-dimensional modeling, the calculation precision is improved while the calculation amount is greatly reduced, and the calculation process is more stable and reliable.
Owner:ZHEJIANG UNIV +1

A method for obtaining the radiation characteristics of divergent and suppressed particles

This invention belongs to the field of radiative heat transfer technology, specifically relating to a method for obtaining the radiation characteristics of divergent suppressed particles. The calculation results of the absorption factor and scattering factor obtained by this method are in good agreement with those obtained by traditional Mie scattering calculations. When the shape factor increases to the point that traditional Mie scattering calculations diverge, the proposed divergent suppressed particle radiation calculation method does not diverge, effectively solving the divergence problem that occurs in traditional Mie scattering calculations when the shape factor increases. By introducing the divergent suppressed Riccati-Bessel formula and stepwise recursive calculations, the stable calculation of the absorption factor Qa and scattering factor Qs is ensured, avoiding divergence and thus improving the reliability and accuracy of particle radiation characteristic calculations.
Owner:BEIJING AEROSPACE INST FOR METROLOGY & MEASUREMENT TECH

Online detection method and system for expansion ratio of expandable graphite

The invention relates to the technical field of material analysis, and discloses an on-line detection method and system for the expansion rate of expandable graphite, and the method comprises the following steps: applying instantaneous high-temperature stimulation to a powder sample to obtain an expanded graphite fluffy body; projecting a structured light field to the fluffy body and collecting a reflected light signal; decoding the optical signal, separating depth information and two-dimensional image information, and obtaining an effective three-dimensional data point set through space matching; performing triangulation processing based on the point set spatial topological relation, and constructing a triangular mesh; re-sampling the triangular mesh to obtain three-dimensional point cloud data, and respectively calculating a real-time accumulation volume and an original theoretical volume according to the three-dimensional point cloud data and the original mass and density of the powder sample; and finally, performing correlation analysis on the real-time accumulation volume and the original theoretical volume to obtain a real-time expansion rate value. According to the method, the accuracy of online detection of the expansion rate of the expandable graphite can be improved.
Owner:QINGDAO PINGYIHONG TECHNOLOGY CO LTD

A method for calculating implicit heat transfer of moving particles using a multi-time-layer difference scheme

A multi-time-layer differential scheme for implicit heat transfer calculation using moving particles is presented, with the following specific steps: 1. Before calculation, virtual particles are arranged at the boundary to implement boundary layout, using virtual particles to arrange the first, second, and third types of boundaries for heat transfer calculation, as well as symmetric and periodic geometric boundary conditions; 2. During heat transfer calculation, the physical and mathematical relationships between different particles are given according to the input boundary conditions; 3. The distances between particle i and its neighboring particle j from the boundary surface formed by the boundary particles are calculated, and boundary conditions are applied; 4. The particle properties are given according to the initial input temperature, and the calculation time step length is given according to the stability condition; 5. The coefficient matrix and source terms of the multi-time-layer scheme of the heat diffusion equations are combined to solve the energy equation for temperature; 6. A consistent solution is performed using relevant solving algorithms to solve for the next temperature and determine whether convergence has occurred; 7. After all MPS calculations for a single time step are completed, the next time step is initiated.
Owner:XI AN JIAOTONG UNIV

A CT image enhancement method and device based on global consistency optimization

PendingCN122089577Asuppress random noiseImprove peak signal-to-noise ratioImage enhancementMicro imagingRadiation Dosages
This invention discloses a CT image enhancement method and apparatus based on global consistency optimization, comprising: performing Gaussian fitting on the pixel intensity distribution of a low-dose CT image to obtain a fitting result containing multiple categories of Gaussian distribution components; calculating the probability of each pixel intensity belonging to each category of the Gaussian distribution component based on the fitting result, and assigning a pixel label to each pixel accordingly; constructing a global optimization objective function containing consistency constraints of adjacent pixel labels, and adjusting the pixel labels through iterative optimization to maximize the objective function, obtaining optimized pixel labels; and performing adaptive deviation reduction processing on the intensity value of each pixel by shrinking it towards the mean of the Gaussian distribution component corresponding to each optimized pixel label, thereby generating an enhanced CT image. This invention can simultaneously achieve noise suppression and detail preservation under low radiation dose conditions, and is applicable to scenarios such as industrial non-destructive testing, medical diagnosis, and high-resolution microscopic imaging.
Owner:SUN YAT SEN UNIV

A fractal dimension calculation method, device, equipment and storage medium

The present invention discloses a fractal dimension calculation method, device, equipment and storage medium, which relates to the field of fractal dimension technology, and includes the following steps: obtaining data to be analyzed, the data to be analyzed includes image data and data with fractal geometric features; performing feature extraction on the data to be analyzed to obtain a three-dimensional feature map, and converting the three-dimensional feature map into a feature matrix; performing outlier processing on the feature matrix to obtain an image matrix; inputting the image matrix into a box algorithm to obtain the fractal dimension of the data to be analyzed. The present invention first performs feature extraction on the data to be analyzed, which can more effectively capture the feature information of edges and details in the data to be analyzed, processes the outliers in the feature matrix, so that the analysis dimension calculated by the box algorithm is more accurate, and can stably perform fractal dimension calculation in a complex environment.
Owner:HAOFEI WEATHER (CHENGDU) TECHNOLOGY CO LTD

A delivery system planning assistance system

The application discloses a kind of delivery and distribution system planning auxiliary system, comprising: management and control center and database, data acquisition module, existing power grid analysis module, load prediction module, power grid planning module and evaluation module are connected with communication in management and control center, database is used to store the data generated by each module, wherein data acquisition module obtains historical power grid distribution map, original data and the basic information of power grid equipment by document scanner, existing power grid analysis module and load prediction module are based on the data collected by data acquisition module to analyze existing power grid and predict future annual load, power grid planning module is based on the analysis result of existing power grid and future annual load to optimize existing power grid planning scheme, and the reliability of new power grid planning scheme is calculated by power flow calculation method in evaluation module.The grid system of the application can be stable calculation and fault analysis, and does not involve the dynamic characteristics and transition process of system elements, improves the reliability of power grid planning.
Owner:GUIZHOU POWER GRID CO LTD