Product
Patsnap Eureka
For R&D, Patsnap Eureka makes reading and utilizing patents & technical documents easy.
Patsnap Eureka AIR
Designed for self-driven R&D workflows. Generate viable solutions, solve complex R&D challenges, empower your innovation with AI.
Patsnap Eureka Materials
Designed for material experts only. Revolutionize your material R&D, from search, analyze, to developing new materials.
Feature
TechResearch
Generate reliable direction feasibility study reports for your R&D in just a few steps.
TechSeek
Discover and master advanced knowledge NOW. Basics, ideas, possibilities, all at once.
TechMind
As an expert in R&D Theories, TechMind can generates customized viable solutions instantly.
TechRisk
Analyze your overall solution with one click, know your potential R&D risks in advance.
TechMonitor
Get weekly tech updates, stay abreast of the latest tech innovations and key insights.
Patents
Literature
Hiro is an intelligent assistant for R&D personnel, combined with Patent DNA, to facilitate innovative research.
1727results about How to "Calculation method is simple" patented technology
Efficacy Topic
Property
Owner
Technical Advancement
Application Domain
Technology Topic
Technology Field Word
Patent Country/Region
Patent Type
Patent Status
Application Year
Inventor
Method for reconstructing digital rock core and pore network model based on random fractal theory
ActiveCN104573198AEasy to set upHigh precisionSpecial data processing applications3D modellingRock coreCapillary pressure
The invention discloses a method for reconstructing a digital rock core and pore network model based on a random fractal theory. The method comprises the following steps of based on the multiple fractal features of a porous medium, performing fractal representing on a capillary pressure curve obtained by the conventional mercury intrusion method, inferring fractal expressions of random distribution density function, average value and variance by a random distribution theory, and combining the random theory and the multiple fractal theory to construct a digital rock core, so as to rapidly construct a three-dimensional micro-network model. The method has the advantages that the cost is low and is reduced; the capillary pressure curve is measured by the mercury intrusion method, the full-section rock core is used in experiment, and a micro-pore structure is fully displayed. According to the method, the computing method is simple and convenient, and the advanced method is adopted; the micro-pore structure of reservoir rock is complicated and irregular, and an extremely complicated system cannot be accurately described by the traditional classical theory, so after the method combines the multiple fractal theory and the random distribution theory, the micro-pore structure can be accurately represented, and the method is easily implemented by programming.
Owner:YANGTZE UNIVERSITY
Image generating method, apparatus and image composition equipment
ActiveCN101394485AGenerated in real timeCalculation method is simpleTelevision system detailsColor television detailsLightnessImage synthesis
The invention discloses a picture generating method, which comprises the following steps: generating at least two pictures with different exposure time; acquiring the pixel luminance values in the pictures with the different exposure time respectively; acquiring the pixel luminance reliability in the pictures with the different exposure time respectively; multiplying the corresponding pixel luminance values in the pictures with the different exposure times by the corresponding reliability respectively and adding up each multiplication result, and then acquiring the pixel luminance values in composite pictures to generate the composite pictures. By applying the technical proposal provided by the invention, the pictures with rich details can be generated in a real-time manner.
Owner:HUAWEI TECH CO LTD
System and method for detecting insulation of electric automobile DC charging pile
InactiveCN105004979AAccurately judge insulation faultsCompact structureTesting dielectric strengthResistance/reactance/impedenceElectrical resistance and conductanceCommunication unit
The invention discloses a system and a method for detecting insulation of an electric automobile DC charging pile, and belongs to the field of electric automobile charging piles. The system comprises a bridge-type impedance network, a voltage conditioning circuit, an isolation unit, an A / D sampling unit, a main control unit, a communication unit and a fault alarm unit, wherein the bridge-type impedance network is used for detecting voltage information of the DC charging pile, and the voltage information is processed sequentially through the voltage conditioning circuit, the isolation unit and the A / D sampling unit and then sent to the main control unit; the main control unit calculates the voltage information processed by the A / D sampling unit so as to acquire a positive bus ground insulation resistance value and a negative bus ground insulation resistance value of the DC charging pile, the main control unit controls the fault alarm unit to alarm on the one hand, and on the other hand, the main control unit sends a calculated resistance value to an electric automobile DC charging pile control system through the communication unit. The system and the method disclosed by the invention are simple in circuit structure, reliable, high in precision, high in anti-interference ability and capable of effectively carrying out insulation detection on the electric automobile DC charging pile.
Owner:JIANGSU WANBANG DEHE NEW ENERGY TECH CO LTD
Blood vessel of brain circulation kinetic analysis method and apparatus
InactiveCN101172042ACalculation method is simpleEasy to detectUltrasonic/sonic/infrasonic diagnosticsData processing applicationsNetwork modelAnalog-to-digital converter
The invention relates to a brain vascular blood circulation dynamic analysis method and the apparatus thereof. According to the cerebral circulation vascular bed anatomical model, an equivalent network model which comprises 12 pipeline units simulating the brain circulation blood dynamics is built, and the relevant parameter calculation formulas are confirmed, by utilizing the formulas, the flow rate waveform and the value inside the cartid artery, the pressure waveform, the blood pressure of the body, the diameter of the blood vessel, the flow rate waveform and the valve of the vertebral artery and the front, the middle and the rear parts on two sides inside the skull, and the characteristic and the parameter of the cartid artery and each blood vessel section inside the skull can be determined, the apparatus designed by the invention can be performed, the detecting system comprises the vessel diameter detecting of the cartid artery outside the skull, the blood pressure detecting, theblood flow rate detecting of the cartid artery outside the skull, the pressure waveform detecting of the cartid artery outside the skull, and the blood flow rate detecting on the artery inside the skull; the control system comprises a control module and a power supply module; the calculation and analysis system comprises a host computer, a peripheral equipment, and an analog-digital converter, the invention can fully analyze the brain circulation dynamic characteristic, thereby having notable effect on the early stage and the ultra early stage diagnosis and therapy of the brain vascular illness.
Owner:SHANGHAI KUANGFU MEDICAL EQUIP DEV
Attitude control method
ActiveCN106915477AImprove performanceReduce development costsCosmonautic vehiclesAttitude controlAttitude controlGuidance control
The invention discloses an attitude control method. The attitude control method comprises the following procedures that the on-satellite time influencing the satellite attitude precision is aligned through a second pulse signal; a satellite sensor error used for satellite attitude measurement is corrected in real time; the gravity gradient disturbance torque of an oblique flying satellite is compensated through a dynamics coupling relationship; the satellite flexibility is restrained through an input forming control method in the attitude controlling process; the attitude control law of an angular velocity feedforward instruction is increased through position and speed double loops and a position correcting loop to achieve high-precision and high-stability attitude guidance control; and quick attitude maneuver of the large-inertia satellite is achieved through a saturated sliding mold structural control algorithm. The attitude control method has the advantages that the computing method is simple, control is flexible, the attitude control method can be applied to attitude control of the large-inertia large-flexible oblique flying satellite, the property of the satellite is greatly improved, and researching and manufacturing cost of satellite hardware is reduced.
Owner:SHANGHAI AEROSPACE CONTROL TECH INST
Crop evapotranspiration model-based intelligent drop irrigation control system and method thereof
InactiveCN102160520AImprove economyHigh feasibilityClimate change adaptationWatering devicesDriver circuitCrop evapotranspiration
The invention relates to a crop evapotranspiration model-based intelligent drop irrigation control system and a method thereof. The drop irrigation system is arranged in a greenhouse and is characterized by comprising a data acquisition module, multiple A / D conversion modules connected with the data acquisition module, a controller (3), a D / A conversion module, a driving circuit and an execution mechanism, wherein the data acquisition module is used for acquiring a corresponding input signal, the signal output terminal of the data acquisition module is connected with the signal input terminal of a corresponding A / D conversion module, the signal output terminal of the A / D conversion module is connected with the signal input terminal of the controller (3), the controller (3) controls an output driving circuit connected with the controller, and the execution mechanism is operated by virtue of the driving circuit to realize irrigation. In the invention, the evapotranspiration is calculated and is indirectly taken as irrigation volume to carry out irrigation on a crop, and moisture required by the crop is supplemented more accurately; and the structure is simple, and the cost is low, thus the system and the method provided by the invention have high promotional value.
Owner:NANJING AGRICULTURAL UNIVERSITY
Direct error compensation technique for five-degree-of-freedom mixed-connected robot
ActiveCN106625573AExcellent error compensation effectCalculation method is simpleProgramme-controlled manipulatorDegrees of freedomComputer science
The invention discloses a direct error compensation technique for a five-degree-of-freedom mixed-connected robot. The direct error compensation technique comprises the following steps that a coordinate system is built, parallel mechanism pose error detecting and estimating are conducted, and series rotating head pose error detecting and estimating are conducted; and mixed-connected robot pose error estimating and compensating are conducted, and the pose error of the mixed-connected robot in a work space is detected till the precision meets the requirements. The direct error compensation technique for the five-degree-of-freedom mixed-connected robot combines the characteristics that the work space of a series robot is large and the acceleration and rigidity of a parallel robot are high, aims at high-speed and high-precision machining, has wide application prospects in the machining and manufacturing field under the large-scale non-structural environment and is suitable for robot error compensation.
Owner:洛阳天扬智能科技有限公司
Data assimilation method for monitoring soil moisture
InactiveCN101614651AOptimizing Ecological Process Model ParametersImprove predictive performanceMaterial analysis by optical meansElectromagnetic wave reradiationDynamic modelsModel parameters
The invention discloses a data assimilation method for monitoring soil moisture. The method provided by the invention at least comprises an assimilation cycle, and each assimilation cycle comprises the following steps: (1) an ecological process model serves as a dynamic model to stimulate the space distribution state of soil moisture every day, the initial value in the dynamic model is an initial parameter and an initial soil moisture data, and the dynamic model is operated to output simulative soil moisture data; remotely sensed data on the soil surface is performed with inversion to obtain surface layer soil moisture data; the simulative soil moisture data in the remotely sensed data corresponding date is combined with the surface layer soil moisture data obtained by remotely sensed data inversion for data assimilation so as to obtain an optimized ecological process model parameter; (2) the optimized parameter is substituted into the dynamic model in step (1) to operate the dynamic model so as to obtain simulative soil moisture data every day. The method provided by the invention can connect soil moisture variety with vegetable physiological response mechanism by water deficit and stress, which improves the precision of field soil moisture monitoring and drought evaluation and has important application prospect.
Owner:PEKING UNIV
Graphical User Interface Manipulation Method
InactiveUS20100083180A1Easy to identifyLight loadInput/output processes for data processingGraphicsGraphical user interface
An input apparatus includes an input unit via which a user can point specific coordinates on a screen, and a display unit for displaying a graphical user interface (GUI). A menu for selecting an arbitrary item from a plurality of items is displayed on the GUI. When the user conducts manipulation to move a location of coordinates pointed by the user on the screen so as to draw a circle, center coordinates of a circle locus of the manipulation are presumed regardless of the location of the coordinates. An item selected in the menu is moved so as to be associated with a rotation angle of the manipulation with respect to the center coordinates. The user can conduct selection manipulation of consecutive menu items without depending upon the location of coordinates pointed by the user on the screen.
Owner:HITACHI CONSUMER ELECTRONICS CORP
Sound source direction judging device and method as well as microphone directivity regulating system and method
ActiveCN106251857AEasy to receiveGuaranteed validitySpeech analysisMouthpiece/microphone attachmentsSound sourcesBeam direction
The invention discloses a sound source direction judging device, a sound source direction judging method as well as a microphone directivity regulating system and a microphone directivity regulating method. The sound source direction judging device comprises a noise filtering unit, a direction computing unit, and a microphone array composed of three pairs of microphones symmetrically distributed in the positive and negative directions of the X axis, the Y axis and the Z axis, wherein the microphone array is used for receiving sound wave signals of a sound source, and transmitting the sound wave signals to the noise filtering unit; the direction computing unit is used for calculating direction coordinates of the sound source according to the sound wave signals with noise signals filtered out, and judging the direction of the sound source according to the direction coordinates of the sound source. A directivity regulating unit of the microphone directivity regulating system obtains the direction coordinates of the sound source calculated by the sound source direction judging device, regulates the beam direction of the microphone array so that the beam direction is towards the direction coordinates of the sound source, and controls the microphone array to only receive sound waves emitted from the sound source direction, so that voice signals are well received, good voice enhancement and noise attenuation effects are realized, and the effectiveness and reliability of speech communication are realized.
Owner:QINGDAO GOERTEK
Cargo vehicle security state previous warning method based on braking distance
InactiveCN101983881AAccurate calculationHigh precisionPedestrian/occupant safety arrangementAnti-collision systemsSecure stateEngineering
The invention relates to a cargo vehicle security state early warning method based on braking distance, in particular to a determination method of the early warning threshold of the on-road vehicle. Aiming at the condition that the on-road vehicle is easy to have some potential dangers, the method of the invention uses the braking distance as the starting point to reflect the secure state of the vehicle. The real-time monitoring method of the on-road state of the vehicle comprises the following specific steps: extracting various factors of the vehicle such as the brake parameters, the current state factor and the outer road environment factor to perform information integration, using a braking distance model to calculate the required braking distance d1 of the current vehicle, comparing with a safe braking distance d0, calculating the degree of risk to determine the current danger condition of the vehicle, and using the range of the degree of risk as the early warning threshold of the vehicle to perform graded early warning. The invention has high instantaneity, precision and accuracy, does not require complicated calculation and design and provides a scientific and effective method for the determination of the danger condition threshold of the vehicle.
Owner:JILIN UNIV
Anti-noise method and device of touch screen
ActiveCN105045426ASuppression of common mode noiseCalculation method is simpleInput/output processes for data processingComputer visionData processing
The invention provides a touch screen data processing method for inhibiting noise and a touch screen control device which applies the method. The method comprises the following steps: (1) receiving an analog signal of a touch screen, and sampling the analog signal of the touch screen to obtain a digital signal; (2) according to a sampling value, calculating a reference value corresponding to the sampling point; (3) comparing the sampling value and the corresponding reference value to obtain a deviation, and comparing the deviation with a preset threshold value; (4) if the deviation is smaller than the threshold value, keeping the sampling value, abandoning the sampling value if the deviation is greater than the threshold value, and replacing the sampling value with the corresponding reference value obtained by the calculation; and (5) applying the data obtained in the step (4) to touch information processing, and calculating a touch position. The method can effectively inhibit common-mode noise and improve the detection precision of a touch position. Compared with a traditional noise elimination method, the touch screen data processing method has the following outstanding advantages of being simple in calculation method, small in hardware resource occupation when a touch signal is realized and high in processing speed, is not affected by the length of a scanning signal and can calculate the signals of any length.
Owner:CHIPONE TECH BEIJINGCO LTD
PMSM rotary transformer zero position initial angle calibration method and calibration system
ActiveCN107404272ACalibration is easy to operateCalculation method is simpleAC motor controlVector control systemsThree-phaseDrive motor
The invention discloses a PMSM rotary transformer zero position initial angle calibration method and calibration system. The PMSM rotary transformer zero position initial angle calibration method comprises steps of connecting an PMSM, on which a rotary transformer is installed, to a driving motor, enabling a motor stator of the PMSM to perform three-phase short circuit, using the driving motor to drive the PMSM to rotate forward and maintain at a preset rotation speed, using an electronic control unit to perform sampling on three phase current Ia, Ib and I c and a rotary transformer reading phi read at a same moment, using the rotary transformer reading phi read to perform Park conversion on three phase current Ia, Ib and Ic to obtain current vectors Is,p, calculating a vector angle theta p corresponding the current vector Is,p, using the driving motor to drive the PMSM to rotate backwards and maintaining the rotation at a preset rotation speed, using the electronic control unit to record a vector angle theta n corresponding to a current vector Is,n when the motor is rotated backwards, and calculating that a practical electric rotation angle theta 0 corresponding to the rotary transformer reading zero point angle is a zero position initial angle according to a formula theta 0=(thetap+thetan) / 2-180 degree.
Owner:GUANGZHOU AUTOMOBILE GROUP CO LTD
Test device and test method used for testing three-dimensional strained condition
The invention provides a test device used for testing a three-dimensional strained condition. The device structurally comprises 12 strain gauges, wherein an arrangement mode of the 12 strain gauges is that two strain gauges are put into one group, the 12 strain gauges are respectively stuck on six edges of a regular tetrahedron, and the six edges are hinged to form a regular tetrahedron skeleton OABC. Meanwhile, the invention also provides a test method used for testing the three-dimensional strained condition. The test device used for testing the three-dimensional strained condition and the test method used for testing the three-dimensional strained condition provided by the invention have the effects that the device and the test method have the advantages of low price, simple computation method, reasonable construction and convenience in operation. A direct and effective means is provided for better understanding the strained condition and stress condition in a stressed body. A three-dimensional strained rosette is arranged in a material to be tested, and 12 strain values on six edges of the three-dimensional strained rosette are read. According to the measured strain values and a spatial position relationship between the three-dimensional strained rosette and the material to be tested, the magnitude and the direction of the main stress, the maximum shearing strain, the volumetric strain and the generalized shear strain of the object to be tested are calculated according to requirements. The invention fills up a blank in the measurement of the three-dimensional strained condition of an object.
Owner:TIANJIN CHENGJIAN UNIV
Alternating-current phasor analysis method and modeling method for phase-shifting control dual active bridge direct-current converters
InactiveCN105099200ASimple calculationThe analysis result is accurateDc-dc conversionSpecial data processing applicationsThree levelDecomposition
The invention provides alternating-current phasor analysis method and small signal model modeling method suitable for dual-active bridge (dual active H bridges, dual three-level half bridges or a three-level half bridge on one side and an active H bridge on the other side and the like) direct-current converters in all phase-shifting controls. The alternating-current phasor analysis method and small signal model modeling method comprise the specific steps as follows: (1) an alternating current side of each active bridge is equivalent to two square-wave voltage sources through equivalence, and square-wave voltage is decomposed into superposition of sinusoidal voltage through Fourier series decomposition to obtain phasor expressions, as shown in the specification, of (2n+1)th component voltage and inductive current; (2) phasor diagrams of control characteristics and control ranges under different phase-shifting controls are obtained according to the phasor expressions in the step 1; (3) complex power, as shown in the specification, of the (2n+1)th component is obtained according to the phasor expressions in the step 1, and active and reactive power characteristics of the dual-active bridge direct-current converters under different phase-shifting controls are analyzed; and (4) time domain Fourier series and expressions of the voltage and the current are obtained according to the phasor expressions in the step 1, so as to obtain a unified signal model suitable for all phase-shifting control methods.
Owner:CHINA UNIV OF MINING & TECH (BEIJING)
Flexible protective shed-tunnel and method for designing same
InactiveCN102493328AImprove flexibilitySimple structureProtective constructionBridge structural detailsBridge deckDesign methods
Owner:INST OF MOUNTAIN HAZARDS & ENVIRONMENT CHINESE ACADEMY OF SCI
Method and apparatus of filtering GPS position drift points
ActiveCN106324626AThe basis for judgment is simple and reliableCalculation method is simpleSatellite radio beaconingCalculation methodsAcceleration Unit
The invention discloses a method and an apparatus of filtering GPS position drift points. The method comprises steps of extracting position data and positioning time of a GPS terminal at a position point; calculating the moving speed of the GPS terminal according to position data and positioning time of adjacent position points; calculating acceleration according to the moving speed and the positioning time of the GPS terminal at the adjacent position points; and determining a GPS position drift point according to the numerical relationship between the moving speed of the GPS terminal and a preset speed threshold, or determining a GPS position drift point according to the numerical relationship between the acceleration of the GPS terminal and a preset acceleration threshold. The invention determines the position drift point according to position data uploaded by the GPS terminal, and filters position points where the moving speed exceeds the threshold and the positive acceleration exceeds the threshold. The calculation method is simple and effective.
Owner:HANGZHOU HIKVISION DIGITAL TECH
Spaceborne dual-channel angle tracking calibration system and method
ActiveCN101923157AAccurately obtain error calibration signalsHigh measurement accuracyRadio wave reradiation/reflectionEngineeringTransmitter
The invention discloses a spaceborne dual-channel angle tracking calibration system and a method. The system comprises an antenna device, a polarization duplexer, a synthesis network, a sum-path receiver, a difference-path receiver, a transmitter, a digital signal processor and a calibration device. Due to the calibration device, the system can realize real-time compensation for an angle error signal within each period, thereby improving the system precision; and meanwhile, the calibration device of the invention has the advantages of simplicity and easy implementation.
Owner:XIAN INSTITUE OF SPACE RADIO TECH
Fast calibration method of single-phase electric energy meter
ActiveCN105242233AFast stabilizationReduce waiting timeElectrical measurementsPhase correctionSignal correction
The invention relates to a fast calibration method of a single-phase electric energy meter. According to the fast calibration method, the gain initial value of a power gain correction register of a metering chip of a calibrated meter is preset so as to be fast positioned to a target error value, only a 100%Ib-point 0.5-induction error point is debugged; apparent power deviation and active power deviation are simultaneously obtained at the error point; 100%Ib-point 1.0-resistance gain correction is performed through utilizing the apparent power deviation; 100%Ib-point 0.5-induction phase correction is performed through utilizing the active power deviation; and a 100%Ib-point 0.5-induction error value which has been obtained through calculation is directly utilized to perform 5%Ib-point 1.0-resistance small signal correction, and therefore, too long debugging time of small signals can be avoided. The fast calibration method has the advantages of fast error target value positioning, high meter calibration efficiency and significantly-improved accuracy.
Owner:NINGBO SANXING MEDICAL & ELECTRIC CO LTD
High-strength bolt strength calculating method of wind generating set
InactiveCN102930085ACalculation method is simpleImprove reliabilitySpecial data processing applicationsStress conditionsElement analysis
The invention provides a high-strength bolt strength calculating method of a wind generating set. The high-strength bolt strength calculating method provided by the invention comprises the following steps of: combining a VDI (Virtual Device Interface) 2230 standard and finite element analysis; modeling by using the finite element analysis; setting boundary conditions and obtaining stress increment of a bolt under the external loading effect by solving; and obtaining ultimate strength of the bolt after considering factors in two aspects of influence on the stress by a bolt pre-fastening force supplying manner through the VDI 2230 standard. A screw part is simulated by using a three-dimensional beam unit in a modeling process; and the stress condition is simulated by that a bolt thread part is engaged with a screw hole, and a bolt head and the screw part can be limited by multiple joints. The high-strength bolt strength calculating method is used for reasonably simulating the bolt by more completely considering a comprehensive stress condition of the bolt, can be widely applied to all high-strength bolt strength checks except a tower cylinder connection bolt in the wind generating set, and provides reliable proof for the design of the high-strength bolt.
Owner:CSR ZHUZHOU ELECTRIC LOCOMOTIVE RES INST
Time synchronization method and apparatus
ActiveCN101296048AHigh precisionCalculation method is simpleTime-division multiplexPropagation delayTransmission delay
The invention provides a time synchronization method and a device. The time synchronization method of the invention measures the propagation delay between proximal end equipment and distant end equipment when the distant end equipment is in the state of loop-back so as to realize time synchronization. According to the invention, the influence of the network traffic on the time synchronization result can be avoided.
Owner:NEW H3C TECH CO LTD
Method for measuring liquid phase diffusion coefficient, and apparatus thereof
InactiveCN102445406AAccurate calculation of diffusion coefficientHigh measurement accuracySurface/boundary effectPhase-affecting property measurementsFluid phaseRefractive index
The invention relates to a method for measuring a liquid phase diffusion coefficient, and an apparatus thereof, and belongs to a method for measuring a diffusion coefficient of a liquid by adopting yellow light LED as a light source based on a capillary imaging method. According to the present invention, a transparent capillary is adopted to construct a liquid phase diffusion cell; the specific refractive index spatial resolution measurement capability of the capillary imaging method is adopted to directly observe and record the diffusion regularity of the thin layers of the diffusion medium in the capability, wherein the thin layers of the diffusion medium have the same refractive index; the liquid phase diffusion coefficient is calculated based on the Fick second law. With the present invention, the diffusion coefficient between glycerol and purified water is measured at a room temperature of 25 DEG C, with comparing the diffusion coefficient 0.720*10<-5> cm<2> / s reported by the literature of the traditional holographic interferometry method with the diffusion coefficient 0.715*10<-5> cm<2> / s measured by the method of the present invention, the relative error is 0.69%; the capillary is adopted to construct the liquid phase diffusion cell, such that the amount of the required sample is less, the measurement speed is rapid, the anti-interference capability is strong and the system stability is good.
Owner:YUNNAN UNIV
Correction method for incomplete or deformed quadrangular image
InactiveCN103679638AShorten detection timeNarrow detection rangeImage enhancementImage analysisPattern recognitionImage correction
The invention relates to a correction method for an incomplete or deformed quadrangular image. The method comprises the five steps of edge point detection, abnormal edge point elimination, linear fitting, vertex calculation and image correction. The correction method for the incomplete or deformed quadrangular image is applied to an identification method identification system for certificates such as valuable documents, notes, identification cards and the like, and can be used for rapidly performing edge detection and tilt correction on defect and deformed valuable documents, notes or certificate images.
Owner:GRG BAKING EQUIP CO LTD
Double-feed wind power generator stator short circuit current calculating method under the condition of asymmetric faults
ActiveCN104836503ASolve the blockageCalculation method is simpleElectronic commutation motor controlVector control systemsTerminal voltageControl engineering
The invention discloses a double-feed wind power generator stator short circuit current calculating method under the condition of asymmetric faults. The method comprises the following steps: establishing a voltage equation and a flux linkage equation of a double-feed wind power generator, in the form of space vectors under a stator shaft system; establishing stator and rotor current expressions, and establishing a stator positive sequence flux linkage expression after the faults; establishing a rotor positive sequence flux linkage expression after the faults; establishing a stator positive sequence current expression of the double-feed wind power generator under the condition of an asymmetric fall of voltage at a machine end; establishing a stator negative sequence flux linkage expression after the asymmetric fall of the voltage at the machine end; establishing a rotor negative sequence flux linkage expression after the asymmetric fall of the voltage at the machine end; establishing a stator negative sequence current expression after the asymmetric fall of the voltage at the machine end; and finally obtaining a stator current expression after the asymmetric fall of the voltage at the machine end. According to the invention, the problems of affected relay protection and control accessed to a wind power field, affected safe and stable operation of a wind power generator set and the like, caused by lack of research on a simple and effective stator short-circuit current calculation method under the condition of the asymmetric faults in the prior art are solved.
Owner:ELECTRIC POWER SCHEDULING CONTROL CENT OF GUIZHOU POWER GRID CO LTD
Negative-damping low-frequency oscillation and forced power oscillation distinguishing method
ActiveCN102944798AOscillation suppressionAdapt to the requirements of real-time judgment of the oscillation mechanismElectrical testingWide areaPower grid
The invention discloses a negative-damping low-frequency oscillation and forced power oscillation distinguishing method, relating to scheduling automation of a power system and safety operation of a power grid. The method comprises the following steps of: calculating energy flow direction factors of all generators and load branches based on data acquired by a power grid wide area measuring system (WAMS) when negative-damping low-frequency oscillation or forced power oscillation happens in the power grid; judging whether a definite external disturbance source exists in the power grid; if the definite external disturbance source exists, judging that a low-frequency oscillation mechanism is based on forced power oscillation; and if no external disturbance source exists, judging that the low-frequency oscillation mechanism is based on negative-damping low-frequency oscillation. The negative-damping low-frequency oscillation and forced power oscillation distinguishing method has the advantages that the basis is provided for the power dispatching department to take corresponding measures for rapidly inhibiting oscillation when the power grid has low-frequency oscillation; in addition, the calculating method is simple and feasible, high in calculating speed, capable of meeting the requirement of a real-time oscillation judgment mechanism of the power grid and strong in practicability.
Owner:ECONOMIC & TECH RES INST OF HUBEI ELECTRIC POWER COMPANY SGCC +1
Hard roof mine impact ground pressure hazard risk prediction analysis method
ActiveCN104533443ASituations to Avoid DisastersCalculation method is simpleMining devicesUnderground chambersEnergy absorptionEngineering
The invention discloses a hard roof mine impact ground pressure hazard risk prediction analysis method. The hard roof mine impact ground pressure hazard risk prediction analysis method comprises substituting obtained mechanical parameters into an energy release equation based on an occurred impact ground pressure hazard to obtain the energy increase degree REC; performing the quantitative characterization on the energy absorption degree AEC according to six divided supporting schemes; dividing specific mine impact ground pressure hazard risk prediction analysis frameworks according to the degree of the influence on mining, wherein the formula of the impact ground pressure hazard potential RDP is as follow; calculating the impact ground pressure hazard potential produced in the mining process of the high press area in the process of the newly occurred hard roof breaking and performing comparison on the impact ground pressure hazard potential and the established impact ground pressure hazard risk prediction analysis frameworks to determine the hazard degree of the impact ground pressure. According to the hard roof mine impact ground pressure hazard risk prediction analysis method, the scientific quantification is performed on the impact ground pressure hazard potential induced by the hard roof breaking in a mine, the calculation method is simple, the required mechanical parameters are easy to obtain, and the impact ground pressure hazard risk of the hard roof mine is simply and conveniently determined.
Owner:SHANDONG UNIV OF SCI & TECH
Method for analyzing depth of crack of thin plate based on ultrasonic lamb waves and time-reversal theory
ActiveCN107045017ASolve multimodal problemsEasy to detectAnalysing solids using sonic/ultrasonic/infrasonic wavesProcessing detected response signalTime domainSonification
The invention discloses a method for analyzing the depth of the crack of a thin plate based on ultrasonic lamb waves and a time-reversal theory. The method comprises the following steps: selecting a thin plate with a crack, and stimulating single-mode Lamb waves IA(t) in the excitation point A of the thin plate; carrying out a sectioning technology to obtain a multi-mode domain signal received by a reception point B, carrying out the time-reversal technology to obtain a reconstructed signal I'A(t) at the point A, and calculating the waveform damage index DI of the reconstructed signal I'A(t) and an excitation signal IA(t); selecting thin plates having different crack depths L, repeating above steps to obtain corresponding waveform damage indexes DI, and carrying out data fitting through a least square technology to obtain a relation between the crack depth L and the waveform damage index DI; and detecting a thin plate with the crack having an unknown depth to obtain the DI value in order to determine the crack depth L. The sectional calculation technology is adopted to effectively solve the problem of propagation of the Lamb waves in a sheet having defects; and the r time-reversal theory is adopted to reconstruct the signal waveform in order to solve the multi-mode problem and the unable identification problem of the reception point, caused by long distance transmission.
Owner:中兴海陆工程有限公司
Device and method for measuring chirp parameter frequency response characteristics of electro-optic intensity modulator
ActiveCN103234735ASimple and fast operationHigh measurement accuracyTesting optical propertiesOptical power meterOpto electronic
The invention discloses a device and a method for measuring the chirp parameter frequency response characteristics of an electro-optic intensity modulator, and relates to the technical fields of electronics. The device comprises a tunable laser, a polarization controller, a modulator for electro-optic intensity to be measured, a microwave signal source, a first optical connector, a second optical connector, a single mold optical fiber, an optical power meter, a photoelectric detector, a microwave power meter, a data collecting card and a computer, wherein the tunable laser, the polarization controller, the modulator for electro-optic intensity to be measured, the first optical connector, a dispersion optical fiber group, the second optical connector and the photoelectric detector are sequentially connected through optical paths, and the photoelectric detector, the microwave power meter, the data collecting card, the computer and the microwave signal source are sequentially connected through circuits. The device and the method have the advantages that the measurement precision is high, and the operation is convenient. The device and the method have important application prospects in aspects of optical fiber communication systems, electro-optic intensity modulator analysis and optical signal processing.
Owner:UNIV OF ELECTRONICS SCI & TECH OF CHINA
Living face recognition method based on blink detection
The invention discloses a living face recognition method based on blink detection. According to the living face recognition method, through reading an image in a face video which is detected by a camera, and calculating a distance between a upper eyelid characteristic point and a lower eyelid characteristic point in each image frame, when the number of read frames reaches a frame number threshold, whether a face in the face video is living according to the fluctuation condition of the distance between the upper eyelid characteristic point and the lower eyelid characteristic point in the read image; and if yes, face recognition is performed on the face in the face image. Therefore the living face recognition method has advantages of simple calculation method, low requirement for the image, and effective improvement of accuracy and efficiency in living detection.
Owner:CHENGDU UNIV +1
Vehicle anti-lock brake control method based on least squares support vector machine
InactiveCN101311047AReduce development costsLow costAdaptive controlBraking systemsLeast squares support vector machinePeak value
The invention discloses a method for controlling an anti-lock braking system of automobiles, which bases on least squares support vector machines (LS-SVM) and relates to the technical filed of the electronic control of the automobiles. The controlling method estimates automobile body deceleration according to the wheel velocity peak values of four wheels; the automobile body reference speed is calculated according to the automobile body deceleration and then the reference slip rate of the wheels is obtained by calculation; the angular deceleration of the wheels is calculated according to the angular speed of the wheels; the angular speed and reference slip rate of every wheel are respectively taken as input to construct a controller of the least squares support vector machines; the expected brake pressure of every wheel is calculated; according to the expected brake pressure, a pulse width modulation method is adopted to control the on / off time of an electromagnetic valve, thus controlling the brake pressure and realizing safety braking. The method is applicable to controlling the anti-lock braking system (ABS) of automobiles.
Owner:CHONGQING UNIV OF POSTS & TELECOMM
Who we serve
- R&D Engineer
- R&D Manager
- IP Professional
Why Patsnap Eureka
- Industry Leading Data Capabilities
- Powerful AI technology
- Patent DNA Extraction
Social media
Patsnap Eureka Blog
Learn More Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic, Popular Technical Reports.
© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap|About US| Contact US: help@patsnap.com