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Medium and low voltage distribution network energy efficiency evaluation method based on accurate load measurement data
InactiveCN102208807AClear theoryGuaranteed uptimeElectrical testingSpecial data processing applicationsLow voltageSimulation
The invention relates to a medium and low voltage distribution network energy efficiency evaluation method based on accurate load measurement data. A complete set of whole-process comprehensive energy efficiency evaluation method for a static and dynamic distribution network is constructed in a distribution network energy efficiency evaluation system. Through the method, various attribute elements of the distribution network can be scientifically, integrally and comprehensively reflected. The system is clear in theory. Compared with the traditional energy-saving and loss-reduction modification measures only based on a quarter line loss method and a sweeping approach, the system has more scientificalness and pertinency and provides a brand new thinking and method for energy efficiency evaluation and energy-saving modification for the distribution network. The invention has a valuable reference to specific distribution network energy efficiency evaluation in various regions, makes pointed references to the distribution network planning and modification construction and also helps distribution network operating personnel master the operating condition of distribution network energy efficiency. Scientific and reasonable distribution network construction and modification projects can be instructed and arranged in actual evaluation and planning works, reliable and economic operation of the distribution network is ensured, and huge economic benefits are created.
Owner:CHINA ELECTRIC POWER RES INST +1
Double-shaft continuous rotation-based hybrid type platform inertial navigation system calibration method
ActiveCN108318052AReduce calibration timeFewer transposition stepsMeasurement devicesHybrid typeAccelerometer
The invention discloses a double-shaft continuous rotation-based hybrid type platform inertial navigation system calibration method. The method comprises the following steps: (1) performing coarse alignment to obtain a coarse initial attitude matrix; (2) controlling an outer ring shaft and a platform body shaft of a platform system to rotate at the same angular speed, enabling an inner ring shaftto be under a locked state, and acquiring gyroscope and accelerometer output in the rotating process; (3) resolving an error state equation and an observation equation and calibrating gyroscope scalefactor error, gyroscope mounting error and accelerometer equivalent zero offset; (4) controlling an outer ring frame angle, an inner ring frame angle and a platform body frame angle to lock in a zerostate, rotating the platform body shaft by 180 degrees and locking, and acquiring output data of the gyroscope; (5) controlling the outer ring frame angle, the inner ring frame angle and the platformbody frame angle to lock in the zero state, rotating the outer ring shaft by 180 degrees and locking, and acquiring output data of the gyroscope; and (6) calculating the constant drift of the gyroscope. By the method, the calibration time is effectively shortened and the calibration efficiency is improved.
Owner:BEIJING INST OF AEROSPACE CONTROL DEVICES
Charge-discharge-storage integrated station control method based on improved V2G and priority scheduling
ActiveCN107634532ARandom Load Fluctuation SuppressionFix security issuesFlexible AC transmissionAc network load balancingLower limitElectrical battery
Owner:SHANGHAI UNIVERSITY OF ELECTRIC POWER
Print file identification method based on print font library analysis
ActiveCN103810484AImprove accuracyClear theoryCharacter and pattern recognitionInformation retrievalDeep level
The invention relates to a print file identification method based on print font library analysis and belongs to the technical field of print file identification. The method mainly comprises the steps of extracting the characteristics of Chinese character images of various types of sample printers, through a learning process, training samples into a characteristic value library corresponding to the same Chinese character of various types of printers used by a system, and matching the characteristic value library with characteristic Chinese character libraries sequentially to complete rough classification of the Chinese character libraries; based on the step above, characterizing Chinese characters more deeply through HU-moment characteristic values until the characterized characteristic information can uniquely identify the Chinese characters in the images. The computer identification method for identifying character images of different types of the printers through commonly-used character libraries is clear in theory, simple in process, convenient to operate, rapid and accurate and is an effective and workable method. The method integrates various technologies and useful information to improve the identification accuracy and provides an automatic computer print file identification system for public security and physical evidence identification departments.
Owner:XIDIAN UNIV
Dynamic magnetic resistance based equivalent reactance transient state modeling method of magnetically controlled shunt reactor
ActiveCN101719185ANo truncation errorSolve problemsSpecial data processing applicationsShunt reactorMagnetic reluctance
The invention provides a practical decoupling electromagnetic transient state modeling method for describing the nonlinear magnetic saturation property of a super / extreme-high voltage magnetically controlled shunt reactor (MCSR), comprising the steps of: providing a transient equivalent reactance algorithm on the basis of a dynamic magnetic resistance idea under AC / DC mixed excitation; reflecting the real-time dynamic change property of the saturated equivalent reactance under the condition of the AC / DC mixed excitation; accurately describing the magnetizing and demagnetizing effect of network side AC current on a reversely series-wound DC excitation saturation magnetic circuit in two main magnetic circuits of the super / extreme-high voltage magnetically controlled shunt reactor (MCSR); describing nonlinear magnetic circuit property with arc hyperbolic functions; decoupling a coupling magnetic circuit equation; differencing transient equivalent reactance by an implicit trapezoid integration algorithm with damping; and establishing an electromagnetic transient state model. The invention not only accurately reflects the continuously smooth regulation property of the saturated magnetic circuit of the super / extreme-high voltage magnetically controlled shunt reactor (MCSR) and prevents the numerical oscillation of piecewise linearization algorithm, but also can meet the requirements of real-time / faster-than-real-time simulation computation under the condition of large-range continuous regulation.
Owner:CHINA ELECTRIC POWER RES INST +1
Frequency domain analysis method for ship autopilot system
The invention relates to a frequency domain analysis method for a ship autopilot system, which includes the following steps: building a math model of a controlled object of the ship autopilot system, and establishing an autopilot control system; confirming a closed loop predominant pole of the control system as per expected response overshoot and adjusting time of the closed loop system; confirming the zero pole of the controller based on a root locus diagram and a Bode diagram of the autopilot control system; designing a ship autopilot second-order ahead controller based on the frequency domain method; drawing a simulation block diagram of the helm autopilot control system; and verifying the effectiveness and feasibility through carrying out simulation comparison and analysis of the ship autopilot control system and the traditional PID control system. According to the method, good stability and fewer frequency in auto-steering are realized, helm blades are rotated in a reasonable range, abrasion and leakage of a steering engine system as well as thrust consumption during helm steering can be reduced, so that energy consumption is saved, the heading of the ship can be automatically kept or changed with high accuracy, safe shipping at ordinary times and collision prevention of ships under a severe environment can be guaranteed, and the method has reference value in the practical engineering application.
Owner:SHANGHAI UNIVERSITY OF ELECTRIC POWER
Bridge moving vehicle load identifying method based on Kaczmarz algebraic iterative reconstruction method
ActiveCN104598931AOvercoming Diversity RequirementsEasy inputCharacter and pattern recognitionAccelerometerAlgorithm
The invention discloses a bridge moving vehicle load identifying method based on a Kaczmarz algebraic iterative reconstruction method. The bridge moving vehicle load identifying method includes steps of uniformly arranging photoelectric sensors and accelerometers in bridge preset measuring points; (2) building a simple physical mechanics model of a bridge; solving qn(t) in a time domain by convolution integral to obtain system equation like Af=b, wherein A is a given system matrix, b is a given bridge deck response, and f is a solved moving vehicle load; (4) identifying the bridge deck moving vehicle load f by selecting proper iterative times k, namely the bridge acceleration response by the Kaczmarz algebraic iterative reconstruction method. The Kaczmarz algebraic iterative reconstruction method only needs simple iteration to identify moving load, the iterative formula does not contain other auxiliary vectors except linear equation set, and the bridge moving vehicle load identifying method is convenient to input, clear in theory, easy to popularize and very applicable to identify the moving load.
Owner:NORTH CHINA UNIV OF WATER RESOURCES & ELECTRIC POWER
Camera calibration method of three-dimensional laser imaging system
The invention discloses a camera calibration method of a three-dimensional laser imaging system. The method utilizes characteristics points to establish a camera coordinate system, then obtains six deviation parameters of the camera coordinate system and a carrier coordinate system through differential computing, completes the calibration of the camera coordinate system, and finally obtains the precise conversion matrix from the carrier coordinate system to the camera coordinate system. At present no corresponding method can process the camera calibration method of a three-dimensional laser imaging system. The method provided by the invention is simple and clear, the programming is easy to realize, and the precision of integration of point cloud data and pictures in a three-dimensional laser imaging system is improved.
Owner:BEIJING INST OF AEROSPACE CONTROL DEVICES
Point cloud model true color processing method of three-dimensional laser imaging system
ActiveCN103679647AClearly see the size, shape, position and even detailsClear theoryImage enhancementUsing optical meansColor processingWorkload
The invention discloses a point cloud model true color processing method of a three-dimensional laser imaging system. By a method of combining photos and point cloud, true color information of a scanned object is extracted through coordinate transformation to complete point cloud model true color processing. According to the invention, the trouble that true color processing of a three-dimensional stereoscopic model cannot be carried out at present is solved. Meanwhile, manual judgment is not required, there is no need to distinguish the shape of an object, and the point cloud is directly colored. The method provided by the invention has advantages of fast arithmetic speed, low time overhead and small workload. By the adoption of the method, true color effect of a three-dimensional stereoscopic model can be achieved well.
Owner:BEIJING INST OF AEROSPACE CONTROL DEVICES
Method for measuring static elasticity modulus of concrete
InactiveCN107449656AEasy loading controlHigh precisionStrength propertiesTest requirementsMiddle line
The invention discloses a method for measuring the static elasticity modulus of concrete. The method comprises the following steps: step 1, manufacturing concrete, with the elasticity modulus to be measured, into a standard cubic specimen, taking the specimen as a splitting tensile test specimen, and curing the specimen to a design age according to test requirements; step 2, preloading the specimen till the difference of two times of center line transversal deformation values meets the requirement; step 3, performing an official test on the specimen, and recording load and a center line transversal deformation value under the load when the loading speed is the same with preload and the loading stress reaches 50 percent of splitting tensile strength; step 4, taking the deformation value in the step 3 as transversal total deformation, and computing to obtain the elasticity modulus of concrete. The method is high in accuracy and simple to operate.
Owner:HOHAI UNIV
A setting method for factory-made pre-camber of a large-span underpass type steel truss girder bridge
PendingCN109583119AUniform design lineEasy to operateGeometric CADDesign optimisation/simulationFinite element methodEngineering
The invention discloses a method for setting the factory-made pre-camber of a large-span underpass type steel truss girder bridge, and relates to the technical field of setting of the pre-camber of the large-span steel truss girder bridge. The method comprises the following steps of: preparing a substrate; SS01, arch camber of the underpass type steel truss girder is carried out; the actual lengths of the longitudinal beams and the lower chord members of the underpass type steel truss beam are kept unchanged; The purpose of arching is achieved by stretching the length of the upper chord, the intersection point of the inclined rods and the upper chord is still intersected with the center of an upper chord node, and the structure of the lower bearing type steel truss girder is shown as SS02when the pre-camber is not set: when the pre-camber is not set, the design lengths of the upper chord and the lower chord are consistent. According to the invention, a finite element method is adopted; The method comprises the following steps: calculating theoretical relative pre-camber as an input load parameter, deducing a telescopic formula of rod piece prefabrication blanking, compiling the calculation formula into a MATLAB program, and making a contrast table, so as to quickly and accurately obtain a line shape which is consistent with the theoretical pre-camber, namely obtain the factorypre-camber, thereby guiding the prefabrication of the rod piece.
Owner:FOSHAN UNIVERSITY
Rod type longitudinal tunnel settlement measurement rod, equipment and system
InactiveCN105444732AReduce volumeEasy to installHeight/levelling measurementMeasurement deviceWireless data
The invention relates to a rod type longitudinal tunnel settlement measurement rod, equipment and system. The measurement equipment comprises multiple connecting rods which are sequentially connected, multiple elastic connectors used for connecting two adjacent connecting rods as well as at least one wireless transceiving module, wherein at least one connecting rod is provided with a tilt angle sensor, each elastic connector is fixed on a corresponding tunnel segment, and each wireless transceiving module is connected with the corresponding tilt angle sensor; each tilt angle sensor is used for measuring a tilt angle of the corresponding connecting rod, and the corresponding wireless transceiving module is used for transmitting first settlement data representing a relative settlement state of two adjacent tunnel segments. Compared with the prior art, the rod type longitudinal tunnel settlement measurement rod, equipment and system have the advantages that the relative longitudinal position between adjacent segments is obtained through tilt angle measurement of the connecting rods, the size is small, the installation is convenient, wireless data transceiving is adopted to realize long-term automatic all-weather wireless monitoring for the longitudinal tunnel settlement, the theory is clear, the structure is simple and clear, and the cost is low.
Owner:TONGJI UNIV
Image-based speed measurement method for rocket sled
ActiveCN106771320AOvercoming measurement inaccuraciesHigh measurement accuracyDevices using optical meansCritical positionRocket
The invention provides an image-based speed measurement method for a rocket sled. A high-speed camera is used for shooting an operation process of a sled body continuously; and after completion of a test, pitching and orientation information correction of the high-speed camera relative to a track, sled body feature point extraction, and operation speed calculation are carried out, thereby completing measurement of the operation speed of the sled body. The method has advantages of high speed measurement precision, simple and clear idea, and easy programming implementation. With the method, the speed measurement precision of the key position in the rocket sled test can be improved.
Owner:BEIJING INST OF AEROSPACE CONTROL DEVICES
Method for measuring actual temperature of flames by using all information of radiation spectrum and measuring system
ActiveCN103900723AHighly theoreticalImprove temperature measurement accuracySensing radiation from gases/flamesAction spectrumRadiance
The invention discloses a method for measuring actual temperature of flames by using all information of a radiation spectrum and a measuring system. More theorized data processing is carried out by applying energy level structure correction, and all the information of the radiation spectrum can be used. A keyboard input mode or a data transmission input mode is adopted to obtain energy level structure correction parameters, and finally more accurate actual temperature values of measured flames are obtained. According to the method for measuring the actual temperature of the flames by using all the information of the radiation spectrum and the measuring system, the defect that the actual temperature of the flames can be obtained only by carrying out radiance correction through data with large computational effort when people adopts a multi-spectrum temperature measuring method is overcome. At present, only a few pieces of monochrome radiating power information in the radiation spectrum can be used in the existing multi-spectrum temperature measuring method, and all the monochrome radiating power information, generally several thousand pieces of the monochrome radiating power information, in the radiation spectrum can be used in the method and the measuring system.
Owner:TIANJIN YITONG ELECTRIC TECH DEV
Control method based on output voltage linear control for linear zone
ActiveCN104485865ACalculation method is simpleCalculation method shortenedElectronic commutation motor controlVector control systemsLinear controlControl vector
The invention relates to an air conditioner control technology. Aiming at the problem that a vector control method is likely to cause control errors due to tremendous calculated quantity, the invention provides a control method based on output voltage linear control for a linear zone. The method comprises the following steps: firstly, a system calculates a duty ratio according to the fundamental current amplitude of reference voltage and a direct current bus voltage value; then, the system calculates three-phase voltage control time according to the duty ratio value and controls the running of a motor. Through rebuilding vector control, in particular linear zone modulating control and over-modulating control technology from a brand new angle, the zero vector action time calculation is not required, the calculation method is simplified, and the calculation time is shortened. The control method is suitable for over-modulating control of a variable frequency motor.
Owner:SICHUAN CHANGHONG ELECTRIC CO LTD
Calculation method of electromagnetic field response of dipole source at arbitrary position under layered geological conditions
InactiveCN110376655AImprove calculation accuracyClear theoryElectric/magnetic detectionAcoustic wave reradiationGround layerDipole source
The invention provides a numerical calculation method of an electromagnetic field response of a dipole source at an arbitrary position under layered geological conditions. The calculation method comprises the steps of: step S100, defining stratums according to the position of the dipole source in the layered stratums; step 200, performing orthogonal decomposition on the dipole source; step S300, deriving a Lorentz vector potential expression generated by the unit dipole source in each stratum; step S400, deriving an electromagnetic field expression in each stratum according to the Lorentz vector potential expression; step S500, calculating a Bessel functional integration in the electromagnetic field expression by adopting a Gaussian extrapolation method to obtain a numerical solution of the electromagnetic field; step S600, and acquiring the electromagnetic field response of the dipole source by multiplying the numerical solution by a dipole source moment. The calculation method utilizes the expressions that Lorentz vector potential between the adjacent stratums satisfy, utilizes the particular solution of the stratum where the dipole source locates for circulating recursion to obtain the Lorentz vector potential expressions of all stratums, and obtains the electromagnetic field expression by means of the Lorentz vector potential, finally calculates the Bessel functional integration in the electromagnetic field expression by adopting the Gaussian extrapolation method to obtain the electromagnetic field response of the dipole source, and has the advantages of clear theory and high calculation precision.
Owner:CENT SOUTH UNIV
Road cement concrete pavement strength index evaluation method
InactiveCN106769443AImprove accuracyThe influence of non-material factors is smallMaterial strength using tensile/compressive forcesMaterial strength using steady bending forcesRating systemTest sample
The invention discloses a road cement concrete pavement strength index evaluation method. During rating of a field pavement slab, test results of the flexural strength of a joist test sample, the splitting tensile strength of a molded cylindrical test sample and the splitting tensile strength of a core sample decide whether the strength of the field pavement slab meet a requirement or not. For a low-grade road, just whether the molding splitting tensile strength meets the standard or not needs to be verified. For a high-grade road, the concepts of the molded cylindrical test sample and the molding splitting tensile strength are introduced, a comparison test for the molding splitting tensile strength, the splitting strength of the core sample and the flexural strength is performed through an indoor test, a mutual relation expression of the flexural strength, the molding splitting tensile strength and the splitting strength of the core sample is established in a regression way, the conventional conversion relation expression of the flexural strength and the splitting strength of the core sample is updated, the molding splitting strength converted from the splitting strength of the core sample is taken as a supplement index during acceptance, and a comprehensive strength index rating system is established to be taken as a rating basis for engineering quality acceptance.
Owner:CHANGAN UNIV
High-precision real-time absolute orbit determination method
InactiveCN110988941AImprove reliabilityMeet the needs of high-precision real-time orbit determinationSatellite radio beaconingCarrier signalOrbit prediction
The invention relates to a high-precision real-time absolute orbit determination method. Under the application background of high-precision real-time orbit determination of a satellite-borne receiver,with a pseudo-range and a carrier phase are used as the observed quantity of a filtering equation, state parameters such as satellite operation positions and speeds are stably output with high precision by using extended Kalman filtering and combining a highly nonlinear kinetic model. While the high-precision carrier phase observed quantity is fully utilized, various ways are adopted to improve the operation efficiency, the requirements of high-precision real-time orbit determination of medium and low orbits are met, the orbit determination and speed measurement precision is greatly improved.In addition, the method also has orbit prediction and extrapolation capabilities, so that the reliability of on-orbit output of the navigation equipment is improved to a great extent. The low-orbit satellite scene simulation real-time orbit determination test is carried out on the receiver platform, the technical indexes that the real-time absolute orbit determination position precision is superior to 0.5 m and the speed measurement precision is superior to 0.5 mm / s can be realized; and compared with a conventional pseudo-range real-time single-point positioning method, the provided method enables the orbit determination speed measurement precision to be greatly improved.
Owner:BEIJING RES INST OF TELEMETRY +2
Free shear failure type antivibration and anti-falling lining building and build process thereof
InactiveCN101358466AImprove lodging resistancePrevents brittle shear failureShock proofingLintelBuilding process
A cut-damage-free antiseismic collapse resistant masonry building and a building method thereof belong to the antiseismic and disaster preventing technical field of civil construction structure. The invention is characterized in that a masonry wall provided with an isolation joint or an isolation hole is an antiseismic collapse resistant building of cut-damage-free type. An important antiseismic area bends ahead of a common antiseismic area. In building process, a vertical isolation seam is arranged between a window wall, a lintel wall and the masonry antiseismic wall near the hole. When the masonry wall of beeline-shaped section is cut up, the middle of the long side of the section is provided with a vertical stage slot or the isolation hole. The extra strong efficiency of antiseismic bearing capacity of the masonry wall is controlled to make the masonry wall bend in earthquake. Crisp cut and slide of the whole section is avoided. After bending, the bearing capacity and the rigidity have little retrogression and good tensibility. The building has highly efficient collapse resistant capability, can be used for new construction or antiseismic security and antiseismic reinforcement of the existing masonry building. The invention is especially applicable to masonry houses in highly seismic region and reconstruction after earthquake.
Owner:TAIYUAN UNIV OF TECH
Fractal recognition method for cross-well sand body connectivity on basis of injection and production quantity relation
The invention relates to the technical field of oil-gas field development and discloses a fractal recognition method for the cross-well sand body connectivity on the basis of the injection and production quantity relation. The injection and production quantities of a complex non-linear multi-phase-flow system composed of water injection wells, oil production wells and reservoirs between oil-waterwells are subjected to data recording. By obtaining the fractal dimension of the set of multi-variation injection and production quantity recorded data of the system, implied information of the connectivity of the reservoirs between the oil-water wells can be extracted, the method does not need complex mathematic models and geological static state model parameters, qualitative-quantitative explaining recognition can be achieved, and a new thought is developed for recognition of the connectivity of the inter-well reservoirs. The fractal recognition method has the beneficial effects that the cost is low, production dynamic data are utilized on the basis of the fractal theory, the complex mathematic models and geological static state model parameters are not needed, the theory is clear, the algorithm is simple, and qualitative-quantitative explaining recognition can be achieved.
Owner:ZHEJIANG OCEAN UNIV
HRTF dividing band linear regression method based on physiological parameters
ActiveCN109166592AClear theoryThe results of the linear regression regression are accurateSpeech analysisCharacter and pattern recognitionIntermediate frequencyPrincipal component analysis
The invention provides a HRTF frequency division band linear regression method based on physiological parameters. Firstly, HRTF of different subjects under the same azimuth in a CIPIC database is selected for principal component analysis to obtain principal component under the azimuth. Then, the correlation between principal components and physiological parameters of different subjects at different frequencies was calculated. The physiological parameters of low frequency, middle frequency and high frequency were obtained by statistical method. Finally, through the selected physiological parameters of low-frequency, intermediate-frequency and high-frequency linear fitting, phase reconstruction by the minimum phase method. The invention has different influence on different physiological parameters, The correlation analysis is applied to obtain physiological parameters affecting HRTF in different frequency bands, and linear regression is carried out by using the physiological parameters,so that the HRTF synthesized by the invention is clearer in theory and the results of linear regression are more accurate for each frequency band respectively.
Owner:NORTHWESTERN POLYTECHNICAL UNIV
Device and method for adjusting laser light spot size and positioning target material
The invention relates to a device and method for adjusting laser light spot size and positioning target materials. A clamp used for clamping a piece of photographic paper is placed on a lifting platform, the lifting platform is mounted on an X-Y motion workbench, the X-Y motion workbench is positioned at the base of a multi-threaded hole workbench, a servo motor is in driving connection with the X-Y motion workbench and the lifting platform, a light path system is arranged on the output optical path of an optical laser, the output end of the light path system is arranged directly facing the photographic paper clamped by the clamp, a photoelectric sensor used for receiving optical signals is further arranged at the optical path output end of the optical laser, the photoelectric sensor is connected to an industrial computer, and the industrial computer is in control connection with the servo motor. Dispersed spots are formed on the photographic paper by using the effect of laser shock waves, so that precision measurement is performed, and approximating to required light spot size is achieved step by step; a thin film is used for positioning target materials; dimensions of the dispersed spots measured are used for approximating the required spot sizes.
Owner:WENZHOU UNIVERSITY
Method and device for simulating boundary current influencing seepage flow
InactiveCN101308128AStable Boundary Flow ConditionsExpand the scope of researchMaterial analysisSoil massBoundary current
Disclosed is a method for simulating the influence on seepage by boundary water flow and a seepage apparatus thereof, which apply the axial symmetry characteristic of ring pillar soil sample seepage, combine the pipe flow theory and adopt a pipe flow mode to provide boundary water flow conditions for soil mass seepage on the basis of the traditional seepage theory, and can reappear the action of the boundary water flow process on seepage and reveal the action law and mechanism. Different pipe flow rates represent different boundary water flow conditions according to the flow rate distribution law and flow state change characteristic of pipe flow. The seepage size and boundary water flow conditions are all continuous and adjustable, and the influence on seepage by the boundary water flow can be researched quantitatively. The method and device have advantages of simple implementation and convenient operation.
Owner:TONGJI UNIV
Super-resolution image reconstruction method based on multiple out-of-focus images
ActiveCN107038685AHigh-resolutionHigh precisionGeometric image transformationDiffusion functionPoint spread function
The invention relates to a super-resolution image reconstruction method based on multiple out-of-focus images. The super-resolution image reconstruction method based on multiple out-of-focus images includes the steps: selecting one original resolution sharp image I and n original resolution out-of-focus images Gj; calculating the pre-estimated high solution image Xo of I; utilizing a particle swarm iteration algorithm to estimate the pre-estimated fuzzy radius Rj and the pre-estimated point spread function hj, and performing combined reconstruction on Xo by means of the compression perception technology and according to Gj so as to obtain the current high solution image Xt; taking Xt as the basis of the iterative computation high solution image X; taking Rj and hj as the initial values, and utilizing the particle swarm iteration algorithm to solve the fuzzy radius Rj and the point spread function hj; and performing combined reconstruction on the image X by combination with n images Gj by means of the compression perception technology and according to the point spread function hj, so as to obtain the super-resolution image M. The super-resolution image reconstruction method based on multiple out-of-focus images can perform blind reconstruction on the unknown point spread function, is simple in the algorithm and is high in the operation speed.
Owner:CHONGQING UNIV
Control method for overmodulation of variable frequency motor
ActiveCN104467593ACalculation method is simpleCalculation method shortenedElectronic commutation motor controlVector control systemsControl vectorLinear region
The invention relates to an air conditioner control technology, and provides a control method for overmodulation of a variable frequency motor, and the control method is used for solving the problems that a vector control method is quite high in calculated amount and control errors are prone to occurring. Firstly, the duty ratio is calculated out by a system according to the fundamental current amplitude of reference voltage and DC bus voltage values, secondly, the normalization value of control voltage on DC bus voltage is calculated out by the system according to the control voltage and the DC bus voltage, then, the correspondence of the duty ratio and the normalization value is set up by the system and stored, and finally, three-phase voltage control time is calculated out by the system to control operation of the motor according to the correspondence of the duty ratio and the normalization value. A vector control technical framework, especially a linear region modulation control and overmodulation control technical framework is rebuilt from a brand new angle, action time of the zero vector and the like does not need to be calculated, a calculating method is simplified, and calculating time is shortened. The control method is suitable for overmodulation control over the variable frequency motor.
Owner:SICHUAN CHANGHONG ELECTRIC CO LTD
DC side stability analysis method suitable for multi-terminal DC power transmission system
ActiveCN112510748ASimple designEasy to adjustElectric power transfer ac networkMathematical modelDc current
The invention discloses a DC side stability analysis method suitable for a multi-terminal DC power transmission system, and the method comprises the steps: S1, building a mathematic model, including aDC side system equation and a control equation, of the multi-terminal DC power transmission system under the action of droop control; S2, linearizing a steady-state operation point of the multi-terminal DC power transmission system to obtain a linearized stability analysis model of the mathematical model, and obtaining a transfer function between a direct-current variable quantity and a direct-current voltage variable quantity after the multi-terminal DC power transmission system is disturbed; S3, deriving a DC stability criterion of the multi-terminal DC power transmission system based on the transfer function; S4, judging whether a droop parameter set under the current electrical parameter is in a stable range of the multi-terminal direct-current power transmission system or not based on a stability criterion; if the droop parameter exceeds the stable range, adjusting a controller parameter and / or changing an operation point of the DC power transmission system; otherwise, requiringno processing. The method achieves the quick discrimination of the stability of a DC power grid, and facilitates the design or adjustment of the parameters of the controller by a power system operator.
Owner:HANGZHOU ELECTRIC EQUIP MFG +2
Rotary machinery fault prediction method and system based on health index and particle filtering
PendingCN114792046AClear theoryImplement miningDesign optimisation/simulationSpecial data processing applicationsHealth indexFeature evaluation
The invention discloses a rotating machine fault prediction method and system based on a health index and particle filtering. The method comprises the following steps: firstly, extracting an appropriate health index on the basis of multi-feature evaluation; then, mining an abnormal sample based on the abnormal change of the health index amplitude; based on the periodic characteristic of the rotating machine fault, the fast spectral kurtosis-multipoint optimal minimum entropy deconvolution is utilized to realize early fault characteristic enhancement, approach to an early fault occurrence node and determine a residual service life prediction starting point, and more samples with fault information are provided for subsequent residual service life prediction; and finally, based on a particle filtering method, realizing probability prediction of the residual service life of the rotating machine. The fault prediction method provided by the invention has the advantages of simple theory, relatively high feasibility, relatively high result confidence and the like, and can be suitable for fault prediction under the confidence interval of the rotating machinery.
Owner:NAT UNIV OF DEFENSE TECH
State space analysis method of power regulating system for nuclear power station pile
InactiveCN103020347AClear theorySimplify design stepsSpecial data processing applicationsAnti jammingState-space representation
The invention relates to a state space analysis method of a power regulating system for a nuclear power station pile. The method comprises the following steps of: establishing a mathematical model of the power regulating system for the nuclear power station pile, performing mathematical modeling on each part of the system, establishing a mathematical model of the regulating system, and establishing generalized controlled object mathematical model; converting a generalized transfer function equation in the generalized controlled object mathematical model into a state space model, judging the controllability of the system, configuring a closed loop system desired extreme point, and constructing a system state feedback matrix; and if a zero point occurs in the generalized controlled object mathematical model, adding a PID (Proportion Integration Differentiation) feedback loop on the basis of a state space model, and adopting a state feedback-PID composite control structure. The method has the advantages of effective suppression of the control quantity of a pile power system, high tracking regulating performance, high robustness, certain anti-jamming capability, general significance, wide application range and ideal control effect, and a novel thought is provided for the control specific to complex control objects with zero points.
Owner:SHANGHAI UNIVERSITY OF ELECTRIC POWER
Method for measuring actual temperature of flame by using all information of radiation spectrum and measurement system thereof
ActiveUS20170045398A1Strong anti-environmental interference abilitySimple divisionSensing radiation from gases/flamesRadianceData transmission
The present invention discloses a method for measuring an actual temperature of a flame by using all information of a radiation spectrum and a measurement system thereof. The method includes: conducting more theoretical data processing by using energy level structure correction, wherein all information of the radiation spectrum can be used; and by way of a keyboard input manner or a data transmission input manner, acquiring an energy level structure correction parameter, and finally acquiring a more accurate actual temperature value of a measured flame. The method effectively overcomes a defect that the true temperature of the flame can be obtained by only conducting radiance correction through data processing with great calculations when adpted multi-spectral temperature measurement method. In the existing multi-spectral temperature measurement method at present, only information of several monochromatic radiation capacities in the radiation spectrum can be used; and in the method, information of all the monochromatic radiation capacities, thousands of monochromatic radiation capacities in general, in the radiation spectrum can be used.
Owner:TIANJIN YITONG TRANSMISSION & DISTRIBUTION ELECTRIC TECH
Method for monitoring three-dimensional deformation of coal mining area by utilizing unmanned aerial vehicle image
ActiveCN112577438ACrack the dependency problemRealize 3D deformation monitoringCharacter and pattern recognitionHeight/levelling measurementCoal miningGeophysics
The invention discloses a method for monitoring three-dimensional deformation of a coal mining area by utilizing an unmanned aerial vehicle image. The method comprises the following steps: estimatinga coal mining ground surface influence area; registering the two time phase unmanned aerial vehicle images I1 and I2; after registration, extracting homonymy points from the unmanned aerial vehicle image corresponding to the coal mining surface influence area, and eliminating mismatching point pairs; according to the extracted homonymy points, determining horizontal movement of the earth surface between two times, and performing spatial interpolation to obtain continuous horizontal movement in an image space; calculating a surface subsidence value between two time phases according to the extracted horizontal movement in combination with a relationship between subsidence and horizontal movement in a coal mining subsidence model; reprojecting the horizontal movement to the direction paralleland perpendicular to the mining trend direction, and fusing the horizontal movement and the subsidence value to obtain the three-dimensional deformation value of the earth surface. According to the invention, three-dimensional deformation monitoring of the coal mine area is realized by using the multi-temporal unmanned aerial vehicle images, the problem of dependence of image-based mining area deformation monitoring on SAR images is solved, and the effect of monitoring three-dimensional deformation of the coal mine area is good.
Owner:CHINA UNIV OF MINING & TECH
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