158results about How to "Strong engineering practical value" patented technology

The invention provides a satellite-borne multichannel aerial SAR data channel magnitude-phase error correction platform, wherein, ratio results of magnitude-phase characteristics of other channels and a magnitude-phase characteristic of a selected standard channel can be obtained after selection of the magnitude-phase characteristic of the channel as criterion and complex division operation of the magnitude-phase characteristics of the other channels and the magnitude-phase characteristic. When actual data is processed, that the magnitude-phase characteristics of the other channels except the standard channel is divided by the corresponding ratio results is only needed, thereby errors which are led in by a signal generator are avoided; in addition, though the magnitude-phase characteristic of the selected standard channel is not completely ideal, occurrence of false targets in the azimuth direction can be effectively prevented and an ideal azimuth direction image performance index can be obtained due to the fact that data of each channel is provided with the same magnitude-phase characteristics after magnitude-phase error correction. Simultaneously, error compensation effects are evaluated and adjusted by self adaptive means from the imaging angle, thereby satisfactory compensation effects are obtained.

The invention provides a secondary surveillance radar track extraction method for multimode polling and S-mold roll-calling interrogation. By using the method, false targets under an interference environment can be effectively removed and the accuracy and the real-time performance of the S-mode query are improved. The method is realized through the technical scheme that plot combination is conducted to S-mode plot data which is searched from the same sector of a secondary surveillance radar interrogator, the mean value and the variance of the plot data are calculated, and a real track is initiated after time-space registration; the combined plot data is divided according to the sector characteristic of radar and an associated sector window is created to enter a plot and track processing flow; firstly de-biased measurement conversion is conducted to the associated plot data, a CV (Constant Velocity) model, a CA (Constant Acceleration) model and a current statistical model are combined into a target multi-model, and the interactive input state estimation vector and the variance of each filter under an interactive effect are calculated; interference targets are removed by adopting interference target removing strategies; and unnecessary target files are removed through track management, tracking is ended and a correct target track extraction result of the secondary surveillance radar is given.

The invention discloses a measuring apparatus and a method for the flexibility line shape of a bridge structure. The measuring apparatus is not fixedly arranged on a bridge, the equipment is simple, the realization is easy, the cost performance is high, the operation is convenient, the flexibility line shape of the bridge can be rapidly, objectively, and intelligently sensed and reproduced, the flexibility of the bridge is measured, the overall flexibility change of the bridge can be reflected via the change of line shapes in different times, bridge management workers can be informed of the current flexibility line shape of the bridge in time, especially the flexibility change state, the health and safety condition of the bridge can be analyzed, the bearing ability of the bridge can be fully developed, load limit and the falling of the bridge are reduced, and the practical engineering value is very high.

The invention provides an experiment device and an experiment method for simulating thermal jet flow interference. The experiment device comprises a hypersonic wind tunnel, an experiment model, a bracket, a Laval internal nozzle, a model nozzle, a heater, an air storage tank, an air cylinder and a CF4/SF6 gas cylinder, wherein an air source is compressed and expanded through the hypersonic wind tunnel and then becomes hypersonic airflow to provide an experiment with external flow; a CF4/SF6 gas is mixed with air and then provides the experiment with internal jet flow; the specific heat ratio required by the experiment is obtained through controlling the molar mixing ratio and the temperature of the CF4/SF6 gas and air, so that the requirements on specific heat ratio simulation of the jet flow in the experiment are met; and simulation of a jet flow interference experiment of the specific heat ratio of the jet flow is achieved in a common wind tunnel. The experiment method has the advantages of being relatively long experiment time, free of pollution, low in thermal load and low in cost, and therefore, the experiment method can be used as an effective means for evaluating the performance of the spray pipe of a hypersonic aerocraft.

The present invention provides a pulse Doppler radar polarization anti-jamming method under a complicated interference environment. By utilizing the method of the present invention, the inhibition capability aiming at various interference, such as chaffs, active suppression, cheat, etc., can be improved substantially, and the targets can be detected effectively. The method is realized by the following technical scheme of inputting a radar dual polarization echo signal, determining whether the active suppression-type interference exists, when the suppression-type interference exists, carrying out the polarization cancellation; then calculating the target signal walking time between the front and back pulses, and carrying out the range walking correction on a pulse sequence; and then carrying out the phase-coherent accumulation on a dual polarization channel, shifting the zero to a frequency spectrum center in a frequency shift manner, identifying the channel number of a target in a Doppler-range two-dimensional matrix, setting a two dimensional tracking gate of the target, and carrying out the two dimensional constant false alarm detection in the tracking gate; finally, carrying out the target polarization ratio detection determination, and outputting a signal passing the detection determination as a target signal after the interference inhibition, thereby improving the correct detection probability of the target.

The invention provides a cross-media intelligence target element association analysis system and an association analysis method thereof. The invention can remarkably improve the analysis ability of the target object and the application value of the analysis result to the user. The invention is realized by the following technical scheme: the user interactive operation module selects a decision treemodel corresponding to the purpose of information analysis, a goal-centered model of target elements is established, the user requirement information is sent into an association expansion processingmodule, Reads the target element model of the initial retrieval intelligence set according to the index, obtains the structured data of the attribute items of the intelligence data input into the database module, uses the domain prior knowledge and element expansion rules provided by the external data support module to carry out element expansion, and obtains the new extended target element and element expansion intelligence; Retrieves all the information, and outputs the correlation results of the target events to the support service module, and outputs the target analysis results including the target correlation and the target activity law.

The invention provides a method for identifying a sea ship of an SAR (Synthetic Aperture Radar) image. By use of the method, detection and identification for a sea ship target of an SAR image under different sea clutter backgrounds can be implemented. The method is implemented by the following technical scheme: calculating a global segmentation threshold value of an input sea SAR image based on anaccumulative distribution histogram to obtain an index matrix of a target leakage pixel; for each pixel, self-adaptively selecting an optimal statistical model from a model dictionary through a KS (Kolmogorov-Smirnov) test for clutter modeling, and performing binary segmentation by use of a CFAR (Constant False Alarm Rate) method; removing isolated noise points by use of a local highlight densityon the basis of a binary segmentation result, extracting a connection region, removing the background and calculating corresponding characteristic parameters to obtain a candidate ship target; and constructing a ship target characteristic set by use of a training data set, and calculating the confidence degree of the ship target by a naive bayesian method.

The invention discloses a braking torque control method for a hydraulic hybrid vehicle, which belongs to a braking control method of a hybrid vehicle. A method for distributing the braking torque comprises the following steps: determining an expected drive torque of the entire vehicle under the current conditions according to the operation behavior of a driver on a braking pedal along with the speed condition and load state in the current state; judging the braking mode of the entire vehicle according to the downlink speed and acceleration of the braking pedal; reasonably distributing a braking torque proportional relationship among an engine, a hydraulic hybrid system and the conventional friction braking system; and determining an instruction signal of the friction braking system and a hydraulic regenerative braking system according to a hydraulic accumulator pressure signal and a rotation speed signal of a hydraulic pump motor. The braking torque control method reasonably coordinates the working relationship among the engine, the hydraulic hybrid system and the conventional braking system, and on the premise of ensuring safe braking, improves the recovery rate of the braking kinetic energy of the vehicle, and has relatively high reliability and high engineering practical value.

The invention discloses a diagnosis method for an active power filter switching device open-circuit fault based on model reference analysis. The diagnosis method includes the steps that on the basis of building an actual operation model of active power filter main circuits, a reference model is constructed; measurable active power filters in all sampling periods are used for outputting three-phase compensating currents, and voltage residual errors are generated according to reference analysis of the model; by setting a threshold value and two judgment flag bits, the residual errors are evaluated to detect whether the open-circuit fault happens on an APF switching device or not in real time; if the fault happens, the specific position where the open-circuit fault of the switching device happens is diagnosed according to the two judgment flag bits. The diagnosis method is effectively used for monitoring the active power filters on line and diagnosing faults, and electric, electronic and electric energy quality control devices such as the active power filters and reactive compensators operate reliably and safely.

The invention discloses a universal radar constant false alarm rate detector and a data sorting method thereof. The universal radar constant false alarm rate detector includes a data preprocessing module, a sorting processing module, an RAM control module, a parameter estimating module, a sifting processing module, a threshold generating module and an output logic processing module. According to the universal radar constant false alarm rate detector and the data sorting method thereof, the optimized constant false alarm schemes under multiple clutter environments are organically combined to construct the optimized constant false alarm rate detector in the current environment background, and the defects in an existing solution scheme are overcome. Meanwhile, the universal radar constant false alarm rate detector and the data sorting method thereof have the advantages of high reliability, high real-time performance, high engineering practicability and the like. According to the data sorting method of the universal radar constant false alarm rate detector, a sorting table updated along with data flow in real time is additionally arranged without breaking original data structural flow, the values of a reference unit under the selected sorting number can be obtained by inquiring the sorting table, and therefore real-time processing of data is completed.

The invention discloses a method for determining a high-speed wind tunnel large aircraft model scale and aims at solving the problems that an existing method for determining a large aircraft model scale is high in difficulty, high in costs and inaccurate. The method comprises the following steps of step 1, generating testing computational grids of different model elongations according to numerical simulation of a model; step 2, setting boundary conditions according to testing operating conditions; step 3, performing numerical simulation of testing conditions by utilizing a CFD (computational fluid dynamics ) calculation procedure and obtaining pressure distribution data of side walls; step 4, comparing the pressure distribution date with pressure distribution data of side walls of an empty wind tunnel, performing statistic analysis on the data and substituting the data into judgment criteria, determining the scale of the full elongation of the model and the width of a testing section to further obtain a proper model scale. The method for the high-speed wind tunnel large aircraft model scale determines the high-speed wind tunnel large aircraft model scale according to disturbance pressure distribution of the side walls of panels of the testing section and provides the basis for the formulation of a testing scheme and the design of a model.

The invention discloses a method for detecting the initial position of a rotor of a power robot. The method comprises the steps of firstly exerting three different voltage pulses on a motor by controlling a driving circuit, respectively detecting the phase current response peak values of the phase A/the phase B/the phase C, comparing the phase current peak values of the three phases, initially judging the section where the rotor is located, controlling an inverter to exert a voltage pulse relative to the section again according to the section where the rotor is located, meanwhile, detecting the current peak value of the phase, comparing the current peak value of the phase and the detected current peak value in the first step, selecting the three detection values in the four current peak value detecting processes for triangle function transformation, and finally determining the angle of the initial position of the rotor. The method for detecting the initial position of the rotor of a permanent magnet synchronous motor can detect the initial position of the rotor of the permanent magnet synchronous motor quite accurately, and achieve smooth starting of the motor, the implementation process is simple, any motor parameters are not required to be depended on, the measuring result is accurate, and the method has the high engineering practical value.

The invention provides a harmonic current compensating method based on fast Fourier transform. For an occasion that double-sequence current decoupling control is adopted for chain static synchronous compensator (STATCOM) inner loop circuit control, and harmonic current compensating precision is ensured by correcting a harmonic current instruction under the condition that inner loop control bandwidth is relatively low. The compensating method comprises the following steps of: firstly, respectively performing fast Fourier transform (FFT) analysis on load current and current converter output current; secondly, calculating the errors of a load current amplitude value, a current converter output current amplitude value, a load current phase and a current converter output current phase, and respectively correcting a harmonic current amplitude value and a phase instruction according to the errors; and finally, reconstructing the corrected amplitude values/phases to obtain the harmonic current instruction of a chain current converter. The influence of the bandwidth and delay of a controller on the harmonic current compensating precision is considered to keep the errors of the output current and the load harmonic current within hysteresis width, the harmonic current compensating precision is improved, and the practical engineering value is relatively high.

The invention discloses a method for detecting the initial position of a rotor of a wind turbine system. The method comprises the steps that firstly, the line current peak value is detected and according to the line current peak value, the initial position of the rotor is initially determined, and the polarity of a rotor magnetic pole is judged. According to the method for detecting the initial position of the rotor of the wind turbine system, the initial position of the rotor of a motor of a wind driven generator can be quietly accurately detected and the motor can be smoothly started; the implementation process is simple, any motor parameter is not needed, the measurement result is accurate, and the engineering practical value is quite high.

The invention discloses an INS/DR & GNSS loosely integrated navigation method based on an MEMS inertial component. The INS/DR & GNSS loosely integrated navigation method comprises the following steps:establishing a state differential equation by taking a position error, a misalignment angle and gyro zero offset of an INS/DR system and a scale factor of a speedometer as state vectors; establishingan observation equation according to the position information of the GNSS system and the position information of the INS/DR system; enabling the state differential equation and the observation equation to enter a Kalman filter iteration process to calculate a state vector of the INS/DR system; correcting the position, the speed, the attitude angle and the gyro zero offset error of the INS/DR system by using the state vector to obtain corrected position, speed and attitude information. According to the invention, the performance of a navigation-level device is achieved by adopting a consumption-level IMU, and the gyroscope thermally-induced zero offset estimation method can be used for autonomous learning and adaptive compensation in the system operation process without any offline calibration; the installation error estimation algorithm provided by the invention can be used for autonomous estimation, and strict requirements on assembly are not needed any more.

The invention discloses a decision-making method for electric system multi-objective optimization dispatching and based on evidence reasoning. The decision-making method includes the steps that priority analysis is performed on a plurality of dispatching objectives which electric system dispatching needs to consider, and important objective sets having great influences on dispatching operation are selected; multi-objective optimization is performed on the important objective sets to obtain a Pareto solution set, and the Pareto solution set serves as a candidate solution set to be selected by a dispatcher; multi-attribute analysis is performed on the candidate solution set, confidence coefficient estimation is performed, and the generated confidence coefficient estimation result is used as decision-making evidence; the decision-making evidence is fused according to an evidence inference method, and then confidence coefficient distribution of candidate solutions in different estimation grades can be obtained; the confidence coefficient distribution is mapped into utility values according to a utility function, average utility values of different candidate solutions are compared, and the candidate solution with the largest average utility value is used as a final dispatching scheme. According to the decision-making method, multi-objective operation evidence is effectively fused, the uncertainty of estimation by the dispatcher is considered, and therefore the decision-making method has remarkable engineering practical value and wide application prospect.

The invention discloses a multi-DC-feed AC grid fault calculating method taking DC control characteristics into consideration. The multi-DC-feed AC grid fault calculating method comprises the following steps of inputting system parameters, DC control strategies and fault parameters of an MODC (multi-outfeed direct current) system; forming an AC system sequence network chart through the system parameters and the fault parameters of an AC grid, establishing an AC constraint equation, and establishing a DC constraint equation between the DC voltage and the DC current of a DC side through the DC control characteristics; setting initial values for all variables; establishing converter switch function models SI and SU of every DC subsystem; according to the AC constraint equation, the DC constraint equation and voltage and current switch functions, solving the transient state parameters of the AC side and the DC side of the MODC system; performing iterative computation, and when variable errors meet computational requirements, outputting the computation results of the transient state parameters of the AC side and the DC side of the MODC system. The multi-DC-feed AC grid fault calculating method taking the DC control characteristics into consideration is high in computation speed, accuracy and adaptability and has high engineering practical value in the aspect of setting and cooperation of fault computation and relay protection of multi-DC-outfeed AC grids.

The present invention discloses a dual-polarized SAR image system which is low in target detection false alarm rate and high in detection rate. According to the technical scheme, a receiving and transmitting conversion module receives horizontal polarization signals of an H transmitting antenna and vertical polarization signals of a V polarization receiving antenna at the same time, the polarization form of the transmitting signals is changed, and a data acquisition board carries out digital down-conversion on acquired frequency mixing signal data and converts the frequency mixing signal datato a baseband; the H-channel pulse pressure module and the V-channel pulse pressure module are connected with a reference function module in parallel, the reference function module carries out Dopplerfrequency modulation, Doppler center estimation, distance bending correction, walking correction, parameter estimation and orientation matching filtering on data, and after a dual-polarization SAR image is obtained, determination fusion processing is carried out on the target to obtain a target detection result, and matrix singular value SVD decomposition is carried out on the covariance matrix corresponding to each pixel so as to obtain a characteristic value of the covariance matrix and a polarization entropy value of each SAR image pixel.

The invention discloses a method for measuring a target azimuth angle by using a vehicle-mounted radar and a vehicle-mounted radar. According to the method and the vehicle-mounted radar, spatial domain echo signals are obtained according to the received echo signals of a target; an original spectral peak position corresponding to the peak value of an original spatial spectrum obtained according tothe spatial domain echo signals is determined; a to-be-estimated spatial spectrum angle range interval is determined based on the original spectral peak position; a to-be-estimated spatial spectrum angle is set; a preset APES algorithm is adopted for the angle so as to obtain the estimation result of a target spatial spectrum; and the target azimuth angle of the target is estimated based on the estimated spectral peak position of the target spatial spectrum. According to the method, the to-be-estimated spatial spectrum angle range interval is obtained through fast Fourier transform, so that the value range of the original to-be-estimated spatial spectrum angle can be narrowed; a Q matrix in the preset APES algorithm is obtained only according to a sample correlation matrix, so that the Qmatrix does not transform along with the to-be-estimated spatial spectrum angle; and inversion operation needs to be performed on the Q matrix once, and therefore, the calculation of super-resolutionangle measurement can be realized in a short time.

The invention discloses a continuous electrolytic polishing device of alloy substrate used for coated conductor, which comprises a first anode tank, an electrolytic tank, a second anode tank, a substrate releasing disc, a substrate reeling disc as well as a first liquid storage box, a second liquid storage box and a third liquid storage box, wherein the first anode tank, the electrolytic tank and the second anode tank are sequentially arranged, and the left sides and the right sides of the first anode tank, the electrolytic tank and the second anode tank are all provided with through holes; the substrate releasing disc and the substrate reeling disc are used together with each other for continuously pulling the alloy substrate to be treated out of the inner parts of the first anode tank, the electrolytic tank and the second anode tank through the through holes after tightening the alloy substrate; and the first liquid storage box, the second liquid storage box and the third liquid storage box are respectively communicated with the first anode tank, the electrolytic tank and the second anode tank through circulating pumps. The invention also discloses a method for carrying out continuous electrolytic polishing on the alloy substrate used for coated conductor by using the device. The device has the advantages of simple structure, reasonable design and low manufacturing cost, and can realize continuous electrolytic polishing on hectometer-level alloy substrate. The root-mean-square roughness of the polished alloy substrate is less than 5nm by adopting the method for electrolytic polishing.

The invention particularly relates to a negative-sequence-current-based control method of conversion chain average direct voltage. The method comprises the following steps: comparing the average direct voltage of any two phases of three phases of conversion chain with the average value of direct current of all chain nodes to obtain average direct voltage deviation of the two phases of conversion chain, and processing by a PI (Proportional Integral) controller to obtain the active power deviation of the corresponding phase of conversion chain; combining the active power deviation and the effective value of alternating current side system voltage to obtain the negative-sequence current component instruction of the three phases of conversion chain through the negative-sequence current instruction calculation; transforming the of three-phase negative-sequence current component instruction into dq axis component of negative-sequence current instruction through Park Transform; obtaining the dq axis component of negative-sequence modulation wave voltage through negative-sequence current decoupling control; then carrying out inverse Park Transformation to obtain the reference value of the three-phase negative-sequence modulation wave voltage; and controlling the output of a converter to form a closed-loop control. The method can effectively solve the problem of conversion chain average direct voltage unbalance and has the characteristics of excellent control performance and wide application range.