110results about How to "Verification accuracy" patented technology

The invention relates to a temperature measurement and calibration platform in space vacuum environment. The temperature measurement and calibration platform is favorable for realizing the simultaneous calibration of contact type temperature measurement and non-contact type temperature measurement, so the temperature measurement and calibration platform is served for heat vacuum and heat balance experiments of spacecrafts such as satellites, spaceship and the like. The temperature measurement and calibration platform comprises a constant temperature bath, wherein a double-sub-cavity vacuum cavity, the double-sub-cavity vacuum cavity comprises a first vacuum cavity body and a second vacuum cavity body, the first vacuum cavity body and the second vacuum cavity body are connected with a vacuum pumping device through a three-way valve, standard temperature indicator sensors are respectively arranged on the outer wall of the first vacuum cavity body and on the outer wall of the second vacuum cavity body, the standard temperature indicator sensors are connected with a temperature secondary meter, a laser light path reflecting device is arranged in the vacuum cavity of the first vacuum cavity body for calibrating a non-contact type temperature measuring system based on the tunable diode laser absorption spectrum technology, and the vacuum cavity of the second vacuum cavity body is used for accommodating a temperature sensor for calibrating a contact type temperature measuring system adopting the temperature sensor.

The invention belongs to the technical field of intelligent automobiles, specifically relates to a complex environment radar multi-target tracking and road driving environment prediction method, whichparticularly aims to solve the problems that the position relationship identification of a lane where a target vehicle locates is inaccurate and the robustness and precision of a target tracking algorithm are not high through determination based on a radar original target measurement value in the process that a vehicle having a self-adaptive control function drives in a curve or an intelligent vehicle having an autonomous valet parking function enters and exits from a curved ramp of an underground parking lot. The complex environment radar multi-target tracking and road driving environment prediction method is mainly implemented by present vehicle motion state estimation, millimeter wave radar signal conversion, time synchronization, target motion compensation, data rationality judgment,target measurement value noise reduction, road curvature estimation, target aggregation, target motion attribute and motion state identification, improved adaptive extended Kalman filtering algorithmtracking and data association, road driving environment prediction and key target generation.

The invention discloses a calibration device and method of a six-axis force / torque sensor. The calibration device comprises a calibration workbench, a rotating workbench, a force value loading device, a torque loading device, a calibration switching device and the like. The rotating workbench mounted on the calibration workbench achieves precise angle rotating of the six-axis force / torque sensor, a side pulley support fixed on a stand column can move vertically along with the different height of the sensor, and therefore a steel wire rope is kept in a horizontal state. The calibration device and method of the six-axis force / torque sensor have the advantages of being simple in operation, good in universality, capable of meeting the calibration requirement of the six-axis force / torque sensor in different measuring range, and capable of achieving torque calibration of the senor with a middle measuring range through the way of changing a calibration force arm.

The invention belongs to the technical field of soil detection, and discloses a soil moisture prediction method based on a machine learning algorithm. The method comprises the following steps: establishing a soil moisture data and prediction factor database; soil moisture simulation prediction and time-space characteristic detection: establishing a soil moisture prediction model in an R language environment by adopting a support vector machine, a random forest and a BP neural network algorithm; performing comprehensive evaluation and space-time characteristic analysis on the soil moisture by adopting a related statistical analysis method; analyzing the prediction model through cross validation and other methods, and evaluating the precision of the method through precision indexes; and determining the importance of the soil moisture predictor. According to the method, prediction factors of terrain, weather, soil, vegetation and the like are selected in combination with local actual conditions, and a novel algorithm-machine learning algorithm is introduced to construct a model to predict the soil moisture, so that accurate prediction of the local soil moisture is realized.

The invention provides a signal efficient sampling and reconstruction method based on FRI time-frequency domain comprehensive analysis and relates to the technical field of information and communication. The signal efficient sampling and reconstruction method based on FRI time-frequency domain comprehensive analysis aims to lower Nyquist sampling frequency of signals and improve the sampling accuracy of the signals. In a frequency domain, a frequency spectrum line is used for recording information of high-frequency components of the signals, and the frequency is subjected to logarithm taking and normalized, so that the frequency domain is further compressed. In a time domain, a line segment fitting method is proposed, and time-frequency signals with low frequency are compressed. Since the signals are sampled efficiently in the frequency domain and the time domain, the requirement for the signal sampling quantity is substantially lowered; the signals are processed and recovered in the time domain and the frequency domain according to the FRI theory; meanwhile, the types of the signals capable of being processed according to he FRI theory are expanded, so discrete Dirac flow and continuous signals with high frequency can be both processed according to the FRI theory. The signal efficient sampling and reconstruction method based on FRI time-frequency domain comprehensive analysis is applicable to the signal sampling and reconstruction process.

The invention discloses a method for measuring soil infiltration capability, which comprises the following steps of: S1, acquiring an earth surface image of each frame with a camera; S2, extracting an earth surface humid area in the image acquired by the S1; S3, calculating the area of the earth surface humid area extracted by the S2; S4, correcting the earth surface humid area acquired by the S3; and S5, calculating the soil infiltration capability through the corrected earth surface humid area. The method has the advantages of less water requirement and high precision in the process of measuring, and wide popularization and application value, and can provide an effective, time-saving, labor-saving and precise tool for research on the measurement of the soil infiltration capability, and research in the related aspects such as earth surface runoff formation and soil erosion and the like.

The invention discloses a structuring method of relation model of the resistivity and temperature and the unfrozen water of frozen earth. The method comprises, firstly, preparing experimental equipment; secondly, performing drying condition experiments to obtain the relation between positive-temperature earth sample resistivity and instant moisture content; thirdly, performing freezing condition experiments to obtain the relation between negative-temperature earth sample resistivity and temperature; fourthly, performing relation reasoning of frozen earth unfrozen water content of different initial moisture contents and temperature at negative temperatures; lastly, establishing a relation model of the resistivity and temperature and the unfrozen water of frozen earth. The structuring method of relation model of the resistivity and temperature and the unfrozen water of frozen earth is simple in process, convenient to implement, capable of simplifying detection of frozen earth water content, accurate in measuring results, high in practicality, good in application effects and easy to popularize.

The invention discloses a method for extracting wetland information based on combination of an NDVI and an LSWI, and relates to the technical field of wetland information extraction. In order to solve a problem that an existing method for extracting the wetland information is realized on the basis of focusing on wetland spectral features without taking variations in wetland information along with the season into consideration, thereby affecting extraction of the wetland information. The method specifically comprises the steps of processing original remote sensing and geographic base data; calculating the NDVI and the LSWI according to the remote sensing data; constructing a wetland information extracting model according to decision making of the model to realize extraction of the wetland information; and evaluating the precision of the wetland information extraction of the model disclosed by the invention through comparing the method with other information extraction methods. The method is maximally characterized by fully utilizing the NDVI and the LSWI, and capable of realizing extraction of the wetland information without being restricted by seasons. The method disclosed by the invention realizes extraction of the wetland information effectively, simply and conveniently, and the results can provide data support and scientific basis for effectively carrying out wetland drafting and monitoring and planning, protecting and managing the wetland ecological environment.

The invention provides an online detection method and device for cyclic fuel injection quantity of an engine under the variable working conditions. The specific values of instantaneous intake pressure and instantaneous exhaust pressure to cylinder pressure are calculated according to dynamic intake pressure, dynamic exhaust pressure and dynamic cylinder pressure, and in combination with the instantaneous flowing areas at an intake valve and an exhaust valve, the temperature of working media on the intake side and the temperature of working media on the exhaust side, the instantaneous flows of gas entering a cylinder and gas exhausted out of the cylinder are calculated; the instantaneous flows of gas entering the cylinder and gas exhausted out of the cylinder are subjected to integration, so that the quantity of accumulated gas in the cylinder is obtained when the intake valve is closed; and according to the quantity of accumulated gas in the cylinder when the intake valve is closed currently and the excess air coefficient, the cyclic fuel injection quantity is calculated. The problem that so far, the cyclic fuel injection quantity of the internal combustion engine is difficult to accurately detect online under the transient working conditions is solved, and the nuance of the air intake and fuel injection quantity of each cylinder can be detected accurately.

The invention discloses an aero-engine life prediction method based on a long-term and short-term memory network. The method comprises the steps of dividing the historical data of an engine into a training set, a test set and a verification set; adding a residual life label to each period of the aero-engine in the training set and carrying out preprocessing; designing and training an aero-engine residual life model based on a convolutional neural network and a long short-term memory network; putting the data of the test set into a trained model to obtain an MAE value and an MSE value of the test set in model training; comparing the residual life label obtained in the test set with a real residual life data set to obtain corresponding goodness of fit verification prediction accuracy and feasibility of the method; and packaging the model with the highest accuracy into a computing unit, and visualizing a prediction result. The neural network provided by the invention is high in portability, high in prediction speed and high in prediction precision, the prediction process and result can be completely visualized, and the operation is convenient and simple.

The invention discloses a system for detecting the content of unfrozen water in frozen soil based on soil mass resistivity variation. The system comprises a ground data transmission terminal, a computer and a temperature and resistivity detecting device which is placed in a soil mass, wherein the temperature and resistivity detecting device comprises one detecting unit or multiple detection units which are vertically stacked; the detection unit comprises a sleeve and a data acquisition circuit board; the data acquisition circuit board is integrated with a data acquisition and transmission circuit and a power line; the data acquisition and transmission circuit comprises a first microprocessor, a first data memory, a first wireless communication module, a temperature measurement probe and a resistivity measurement probe. The invention also discloses a method for detecting the content of the unfrozen water in the frozen soil based on the resistivity variation. According to the system and the method, disclosed by the invention, implementation is convenient, a complex problem of detecting the content of the unfrozen water in the frozen soil can be simplified, a measurement result is accurate, the instantaneity and the integrity are good, the practicability is high, the using effect is good, and popularization and use are convenient.

With respect to two or more NC data points among a group of dots together representing a tool locus, a curvature radius of the tool locus is determined. Then, the NC data point and its succession with other points is displayed in a display color determined according to the magnitude of the curvature radius. Alternatively, a movement direction of each minute segment relative to a specific axis selected from the three (XYZ) axes is determined as either positive, negative, or zero, and the minute segment or an end point thereof is display with the display property determined according to the movement direction. Still alternatively, after a specific axis is selected from the three (XYZ) axes, a region relative to the selected region is divided along the selected axis, for predetermined dividing width, first beginning with a predetermined reference point, and the resultant divided regions are given predetermined display properties. Then, a tool locus is displayed in the three-axial (XYZ) system according to the display properties given to the respective divided regions.

The invention provides a method for predicting internal and external temperatures of a power lithium battery, which comprises the following steps of: firstly, constructing a lithium ion battery electrothermal coupling model considering an environment temperature; recognizing parameters of the model through a forgetting factor least square method to obtain model parameters in different environments; then performing simulation level verification on the proposed lithium ion battery electrothermal coupling model established according to the parameter identification result according to dynamic working condition test data; and finally, constructing a state observer considering the environment temperature to verify the application level of the model. The method solves the problem that the state estimation error is large due to an inaccurate model caused by different environment temperatures, and plays an important role in the utilization efficiency and the service life of the power battery pack and the whole vehicle performance.

The invention provides a dynamic performance debugging method and system suitable for a servo system. The method comprises a step of debugging and confirming the property of matching between a servo controller and a motor and the correctness of three phases of the motor, a step of confirming the correctness and accuracy of a sensor, a step of confirming the property of matching between a three-phase current and a rotary encoder and an initial angle of the rotary encoder, a step of controlling a current loop, a step of confirming the correctness of a motor speed solver, a step of controlling aspeed loop, a step of controlling a position loop, a step of realizing control instruction, parameter binding and telemetry message protocol communication, a step of enabling the servo system to havethe predetermined dynamic response performance, and a step of enabling the load servo system to have the predetermined dynamic response performance. Debugging under a load condition can be carried outin a realest environment, so that a simulation link is reduced; a high-power electromagnetic environment can be included; various parameters of the system are most accurate; and at the moment, the optimal dynamic performance of the servo system can be obtained.

The invention discloses a linear calibration system based on a camera coordinate system and a method thereof. The system comprises a coordinate system construction module, an image point position offset estimation module, a focal length calculation module, a camera parameter calculation module and a target point position calculation module. And the coordinate system construction module and the image point position offset estimation module are used for obtaining a theoretical estimation of an imaging point position offset volume. An objective function is established based on an coordinate errorbetween imaging point actual coordinates and imaging point theoretical estimation coordinates. Partial derivatives of the objective function are solved about intrinsic parameters of the camera, and acamera intrinsic parameter linear algorithm is given out. According to the method, the problem of coupling between camera intrinsic parameter and external parameter calculation is solved, a camera calibration parameter calculation model is simplified, and the precision of a camera calibration result is improved.

The invention provides a method for measuring and calibrating the flow volume and velocity of a numerically controlled shot blasting machine. A shot collector is provided. The flow volume and velocity of blasted shots are calibrated by measuring the mass of shots blasted at different flow velocities at the same time. An effective and simple method for calibrating the flow volume and velocity of a numerically controlled shot blasting machine is provided. Through the method, the precision of flow volume and velocity of a numerically controlled shot blasting machine can be verified, and the influence of flow volume and velocity on the shot blasting intensity is controlled effectively. The method separates collecting from weighing. A collecting and weighing integrated device can also be designed to facilitate detection.

The invention discloses a method of estimating the lean meat percentage of a live pig and relates to the field of detection technique, which aims at solving the problems of detection technique for lean meat percentage of the live pig. The method of estimating the lean meat percentage of the live pig comprises steps as follows: 1) measuring the weight of the pig with empty stomach, and determining the sizes of back fat and eye muscles of the live pig by a B-typed ultrasound scanner; 2) substituting the weight, thickness of the back fat and size of the eye muscles into a regression equation of estimating the lean meat percentage of the live pig as follows: y is equal to 67.264 plus ax1 plus bx2 plus cx3; wherein, y refers to the estimated lean meat percentage, x1 the weight, x2 the thickness of the back fat and x3 the size of eye muscles; a represents a number between -0.067 and -0.059, b represents a number between -2.206 and -2.038, and c represents a number between 0.195 and 0.215; then finally gaining an estimated lean meat percentage of the detected pig. The method of estimating the lean meat percentage of the live pig has the advantages of high accuracy and measuring speed, and can determine the lean meat percentage of live pigs, without bringing any loss caused by the slaughtering.

The invention relates to a dynamic response modeling method for a primary frequency modulation system of a wind turbine generator based on propeller pitch control. The method comprises the following steps: solving a small signal increment Delta Pm of mechanical power Pm; establishing a state variable for describing a power control ring; establishing a reference pitch angle beta ref and a mathematic model of a propeller pitch servo actuator; establishing a small signal increment state equation set of a propeller pitch primary frequency modulation input and output control system related to the variable according to the above-mentioned steps; constructing a system state space model and solving a system input and output transfer function. The invention aims to provide a dynamic modeling method for the primary frequency modulation system of a double-fed wind turbine generator for describing the dynamic response of the primary frequency modulation system of similar synchronous generator prime motor-governor, so as to grasp a mathematic description method for the primary frequency modulation response of the wind turbine generator under the disturbance of power system frequency.

The invention discloses a device and a method for verifying insulation monitoring accuracy and leakage protection of a battery pack management system, which are used for verifying insulation monitoring accuracy of a detected battery pack (1) of the battery pack management system. The device comprises a first single-throw switch (K1), a second single-throw switch (K2), a double-throw switch (K3), a variable resistance box (2), an ammeter (3) and a fuse (4), wherein one end of the variable resistance box (2) is connected with the ammeter (3) in series, and the other end is connected with a movable end (c) of the double-throw switch (K3); a first fixed end (a) of the double-throw switch (K3) is connected with a positive electrode of the battery pack (1) through the first single-throw switch (K1) and the first wire harness (5) in sequence; a second fixed end (b) of the double-throw switch (K3) is connected with a negative electrode of the battery pack (1) through the second single-throw switch (K2) and a second wire harness (6) in sequence; and one end of the fuse (4) is connected with the ammeter (3) in series, and the other end is connected a shell body of the battery pack (1) through a third wire harness (7). The device and the method can be used for verifying accuracy of the battery pack management system, and the battery pack management system alarms when an insulation problem of the battery pack occurs, thereby protecting the battery pack, and standardizing the insulation testing method of the battery pack management system.

The invention relates to an automatic dependent surveillance-broadcast (ADS-B) test signal source which comprises a single chip micro-processor, a field programmable gata array (FPGA), a serial port and a control display unit. The FPGA is formed by a read only memory (ROM), a cyclic redundancy check (CRC) and a pulse position modulation (PPM) encoder. The ROM, the CRC and the PPM are connected in sequence in a one-way mode. The single chip micro-processor is connected with the control display unit in a two-way mode, the single chip micro-processor is connected with the FPGA in a one-way mode, a current pare register (CPR) encoder is connected with the ROM in a one-way mode, and the PPM encode, a signal source body, an ADS-B receiver and the control display unit are connected in sequence in a one-way mode. The ADS-B test signal source has the advantages of being used for verifying accuracy and reliability of the ADS-B receiver, good in effect, and high in reliability.

The invention provides a calibrator for calibrating a revolution meter of a diesel engine. A microprocessor is connected with a frequency converter via an RS485 interface circuit, the frequency converter is connected with an alternating-current motor, the alternating-current motor is in driving connection with a simulator of the diesel engine, a signal end of the simulator of the diesel engine is connected with the microprocessor, and the microprocessor is respectively connected with a display circuit and a keyboard circuit via interface circuits. The microprocessor is communicated with the frequency converter via the RS485 interface circuit so as to set the frequency of output revolution speed, accurate output of the frequency converter controls the alternating-current motor to generate stable revolution speed, the alternating-current motor drives oil spraying of the simulator of the diesel engine to generate a vibration signal on a wall of an oil spraying tube, the tested meter is clamped on the wall of the oil spraying tube so that the revolution speed of the meter is measured, and accuracy and reliability of the meter are checked.

The present invention provides a feature weighting filter method based on correlation and a Naive Bayes classification method. The weight value of each feature variable is directly defined as the difference of the correlation of the feature variable and the class variable and the average redundancy of the feature variable and other feature variables. The present invention also provides a feature weighting Naive Bayes classification method depending on the method mentioned above. One group of obtained weighting values is substituted into the Naive Bayes classification formula for final classification of the test example. The feature weighting filter method based on correlation and the Naive Bayes classification method consider the correlation of the feature variable and the class variable and the redundancy between feature variables and maintain the model calculation complexity and the simplicity so as to verify the validity and the accuracy of the feature weighting method and the classification method provided by the invention through lots of experiment researches.

The invention relates to a method for predicting and evaluating the residual life of key parts of a waste machine tool and belongs to the technical field of green remanufacturing systems. According tothe method for predicting and evaluating the residual life of the key part of the waste machine tool, a main failure form of the key part of the machine tool is considered to be fatigue fracture failure, and a continuous fatigue damage model based on fracture mechanics is adopted to predict the life of the waste part so that remanufacturability is determined. The research model better conforms tothe actual working condition so that the prediction and evaluation result is more accurate, precision of predicting and evaluating the main shaft key part model is ensured, residual life calculationaccuracy of the model is ensured, and precision of predicting and evaluating spindle key part models is ensured, meanwhile, data of the secondary load loading fatigue test are compared with the calculation result of the model, and accuracy, effectiveness and feasibility of the corrected model are verified; practice proves that prediction precision of the residual life prediction and evaluation method can meet the actual engineering requirement of waste part remanufacturability evaluation.

The invention discloses a robust optimization design method for a hot air reflow welding process, which comprises the following steps of: establishing a sensitivity analysis method of each noise factor and design variable to a target and a constraint condition by establishing an accurate reflow welding process temperature field simulation model and determining the target and the constraint condition; screening noise factors and design variables which have significant influence on the heating factor; sampling new design variables and noise factors to obtain sample points again, and constructingan agent model of a prediction target function and a constraint function; obtaining an optimal scheme determination solution based on response surface optimization, verifying the precision of the response surface constructed by the agent model, and carrying out robustness evaluation on the optimal solution; and finally, obtaining the most robust solution, substituting the most robust solution into the original simulation model to carry out reliability analysis, verifying robustness, and further carrying out process parameter optimization design according to a robustness target value to ensurethat a process result has robustness.

The invention relates to a device and a method for testing frictional angles of small-diameter particles. The device comprises a controller, a tested plate, a support, a bottom plate, a first rotating shaft, connecting structures as well as a driving device, a tilt angle sensor, a value display module and image capturing equipment which are connected with the controller, wherein the tested plate is detachably arranged on the bottom plate; the first rotating shaft is arranged on the support, a rotation shaft is arranged at the bottom of the support, one end of the bottom plate is rotationally connected with the support through the rotation shaft, the other end of the bottom plate is connected with the first rotating shaft through the connecting structures, and the driving device is used for driving the first rotating shaft to rotate; the tile angle sensor is arranged on the bottom plate and used for measuring an included angle between the bottom of the bottom plate and the horizontal plane, the value display module is used for displaying values of the tile angle sensor, and the image capturing equipment is used for capturing images of sliding conditions of the small-diameter particles on the tested plate. The device is simple in structure and convenient to operate, measured values of the frictional angles can be obtained directly, and the measurement precision is high.

The invention discloses an aircraft model driving system in a wind tunnel and a performance measurement method, and belongs to the technical field of wind tunnel aerodynamics and flight dynamics experiments and comprises a supporting rod device, a six-rod parallel mechanism and a linear guide rail, the supporting rod device is located on the rear part of an aircraft model, and the aircraft model is supported by a multi-component balance in the model; a rolling driving and measuring device is mounted in the supporting rod device; the six-rod parallel mechanism comprises six connecting rods, universal hinges are arranged at the two ends of each connecting rod, and the universal hinge at the front end is connected with the supporting rod device; the universal hinge at the rear end is connected with a sliding block of the linear guide rail; the linear guide rail is installed on the inner wall of the wind tunnel experiment section. Omnibearing, large-range and high-speed movement can be provided in the wind tunnel at the same time, enough rigidity and strength and low interference are achieved, and the method can be used for measuring aerodynamic force and virtual flight performance ofan aircraft with high maneuverability and agility in the high-speed wind tunnel.

The invention relates to a biomechanics modeling method for subcutaneous adipose tissues based on linear elasticity and superelasticity models. According to the biomechanics modeling method, the problems that an existing subcutaneous adipose tissue model is low in simulation accuracy and speed are solved. The biomechanics modeling method comprises the following steps: (1) establishing a geometric model, and dividing grids; (2) establishing a linear elasticity biomechanics model; (3) establishing a superelasticity biomechanics model; (4) carrying out finite element simulation on the superelasticity biomechanics model according to the step (1) and the step (2); (5) carrying out finite element calculation on the linear elasticity model; and (6) carrying out finite element simulation on a mixed linear elasticity and superelasticity model. By virtue of comparison on a simulation result and an experimental result, the accuracy of the biomechanics modeling method is verified. By virtue of comparison on simulation time of the single linear model and superelasticity model, high efficiency of a simulation algorithm of the mixed linear elasticity and superelasticity model is verified. The biomechanics modeling method is applied to the field of biomedical engineering.

The invention relates to a method for simulating rainfall flood of concave flyover, and the method comprises the following steps: S1, collecting data, building a database, and carrying out multi-source data fusion; S2, carrying out rainfall flood simulation on the dynamic change of the sub catchment area by utilizing a rainfall flood model, and carrying out staged simulation on the rainfall floodprocess of the concave bridge area; S3, verifying the simulation result of the step S2 by using an under-bridge digital elevation model. According to the invention, the problems of low simulation precision and lack of verification data in the existing urban rainfall flood simulation are solved; according to the method, the SWMM is adopted to construct the model for rainfall flood simulation, the change of the sub-catchment area in the rainfall flood process is considered, the spatial distribution difference of rainfall is also considered, the simulation precision is greatly improved, and meanwhile, the digital elevation model is adopted to perform back calculation verification on the simulation result, so the rainfall flood simulation precision can be further verified.

The invention provides a verification system of an autonomous orbit control algorithm. Through a simulation computer, a spaceborne computer, a navigational star simulator and a GPS receiver, an autonomous orbit control closed loop test system is established on the ground. The spaceborne computer carries out calculation according to current position information sent by the GPS receiver, and controls and determines whether the autonomous orbit control algorithm is effective according to a result of comparing current attitude data fed back by the simulation computer, current orbit data, preset attitude data and orbit data. The test system can be established on the ground, and effectiveness and accuracy of autonomous orbit control algorithm operation are verified.