65results about How to "Small absolute error" patented technology

The invention discloses a simultaneous localization and mapping method based on vision and laser radar, and belongs to the field of SLAM. According to the method, the laser odometer and the visual odometer are operated at the same time, the visual odometer can assist the laser point cloud in better removing motion distortion, and meanwhile the point cloud with motion distortion removed can be projected to the image to serve as depth information for motion calculation of the next frame. After the laser odometer obtains a good initial value, the laser odometer is prevented from falling into a degradation scene due to the defects of a single sensor, and the odometer achieves higher positioning precision due to the addition of visual information. A loop detection and repositioning module is achieved through a visual word bag, and a complete visual laser SLAM system is formed; after loop is detected, the system performs pose graph optimization according to loop constraints, accumulated errors after long-time movement are eliminated to a certain extent, and high-precision positioning and point cloud map construction can be completed in a complex environment.

The invention provides a device and method for gradient materials additive manufacturing by using two-wire twin-electrode tungsten inert gas arc. A first partial tungsten electrode and a second partial tungsten electrode are installed below a two-tungsten-electrode argon arc additional material manufacturing gun of the device, and are vertically arranged above a base plate. A first wire guide nozzle and a second wire guide nozzle are arranged in front of the two-tungsten-electrode argon arc additional material manufacturing gun. In the deposition process, two metal wires of dissimilar compositions are conveyed to a melting bath at the same time, the composition and performance of a deposition bead are controlled by adjusting the feeding proportion of the metal wires, and thus manufacturingof the gradient material arc additional material is achieved. It is ensured that excellent forming can still be achieved in the deposition process with large current and high wire feeding speed, thecomposition of the prepared gradient material formed part can be continuously transited from the composition of one metal wire to the composition of the other metal wire without replacement of the welding wires, and the deposition efficiency is up to 330 cm<3> / h; and in addition, the deposition bead is more uniform in composition, and the relative error between the components of the deposition bead and target set compositions is smaller than 10%.

Disclosed are a method and system for measuring concentricity and the tip clearance of a rotor and a stator of an aero-engine. The method comprises the steps that the clearance amount of the rotor and the stator of the aero-engine at an initial measurement point is acquired; a clearance maximum jerk value FIR value, the phase of the clearance maximum jerk value FIR value, a maximum deviation IMP value between a sampling profile curve concave point and a mean profile, the phase of the maximum deviation IMP value, an eccentric distance ECC value, the phase of the eccentric distance ECC value, a maximum clearance value relative to the rotation center, the phase of the maximum clearance value, a minimum clearance value relative to the rotation center, the phase of the minimum clearance value, a maximum clearance value relative to the geometric center, the phase of the maximum clearance value, a minimum clearance value relative to the geometric center and the phase of the minimum clearance value are obtained; an angle-clearance distribution diagram is drawn; the clearance amount is corrected in the horizontal placement measurement process; a concentricity error value and the tip clearance of the rotor and the stator of the aero-engine are obtained. The system comprises a sampled data analysis module, a rotor and stator concentricity calculation module, a tip clearance analysis and calculation module and a horizontal-measurement deflection correction module. The method and system are suitable for measuring the concentricity and the tip clearance of the rotor and the stator of the aero-engine.

A method to get the current system time in the global interaction microwave access equipment, includes: sets the time server in the global interaction microwave access MiMAX equipment; the guest room end of the WiMAX equipment sends the information package with the time stamp to the time server; the WiMAX equipment get the current time according to the information package with the time stamp from the time server. The invention can get the more accurate current system time of the user's station and the base station of the WiMAX equipment.

The invention relates to the optical element parameter measurement, particularly relates to a fast and accurate method for testing eyeglass with ultra-high reflectivity. In order to solve the problem that the prior art of testing eyeglass with ultra-high reflectivity has low measurement precision and the debug takes time and labor. The invention includes the following steps: (1) constructing the optical cavity and the affiliated members; (2)coinciding the reference light source and the measuring light source in space; (3) adjusting the calibration moving plate; (4) accurately adjusting the optical path closure degree of the optical cavity; (5) fine adjusting the place of the matching lens, determining the fundamental transverse mode, and causing the laser light source fundamental transverse mode to match with the fundamental transverse mode of the tested optical cavity effectively; (6) fitting by the characteristic time I(t)=I0exp(-tcL / 2d) and obtaining the total loss L of the tested cavity. The invention introduces the visible light source as the reference light which greatly reduces the difficulty of adjusting of the cavity. The invention can measure and screen the optical lens with high quality in batch. The test precision of the method provided by the invention is higher than 5x10-7.

The invention discloses an urban traffic road section speed prediction method and a system based on multi-road-section space-time correlation. The method comprises the steps of acquiring the speeds ofthe latest p historical time points of all road sections in an optimal feature subset corresponding to a to-be-predicted road section; wherein p is a positive integer; and inputting the acquired speeds of the latest p historical time points into a pre-trained GRU neural network, and outputting the prediction speed of the (p + 1) th time point of the to-be-predicted road section. The prediction model quantitatively and dynamically considers space-time correlation among all road sections in a road network from the aspects of traffic parameters, road section connectivity, road grades and the like, and can select a road section subset which is beneficial to speed prediction of a road section to be predicted from the road network. The prediction model can realize accurate prediction of the speed of the urban traffic road section.

The invention relates to a method for estimating the position of the center of mass of a spacecraft, in particular to a method for quickly estimating the position of the center of mass of the spacecraft. The technical feature is that: based on attitude kinematics equations, the center of mass position estimation equation is established by using the least square method. Two accelerometers are installed in the three-axis direction of the spacecraft body, combined with the gyro information, the angular acceleration at each time is calculated, which avoids the calculation error caused by the direct differentiation of the angular velocity to obtain the angular acceleration, and greatly reduces the estimation algorithm. measurement accuracy requirements. The new method for estimating the center of mass of the spacecraft does not need to know the information of the moment of inertia and control moment of the spacecraft, and the algorithm is simple, which can ensure that the absolute error of the estimation of the center of mass of the spacecraft is less than 10 mm.

The invention relates to the technical field of level measurement and particularly provides a method for dynamically measuring fuel capacity of an irregular fuel tank of an aircraft; the method comprises: acquiring fuel volume characteristic data of each sensor, selecting a suitable function formula, fitting data of each sensor at all measurable angles, calculating maximum and relative errors , using the formula if an error index is satisfied, selecting other formulas or segmenting unsatisfactory index points if the index is not satisfactory until the index is satisfactory, receiving sensor data and aircraft attitude parameters, acquiring effective sensor formula fitting parameters, calculating fuel volume solved by each sensor to obtain fuel volume value of a single fuel tank, syncing aircraft fuel level angle and sensor height information under dynamic conditions according to test or trial data so as to obtain more accurate fuel volume of the fuel tank.

The invention relates to an arc light protection unit on-line test method, (1) installs the arc light sensor in the switch cabinet, and around the arc sensor fixed the simulation light source of which light intensity is adjustable; (2) under the electric system normal operation condition, through the change-over switch temporarily relieves the arc light protection unit and the electric system electrical connection, and connect with the test unit; (3) the test unit contrl the simulation fault current and simulation light intensity which brought to arc protection unit, the movement performance of test arc protection unit under the certain intensity light and current effect; (4) the test unit automatic logging the arc protection unit test result under the certain intensity light and current effect, judge the arc protection unit operating whether or not normal. The invention can on-line test and log the precise movement parameter of the arc protection unit under the different current and light intensity effect, and supplies a precise test means for guaranting the arc protection unit unitreliable movement.

The invention relates to a track data processing method and device, computer equipment and a storage medium. The method comprises the steps that track starting data and track ending data correspondingto a target object are acquired, wherein the track starting data and the track ending data are obtained according to positioning, or the track starting data and the track ending data are closed-looptrack data; a corresponding initial correction track data sequence is acquired according to the track starting data and the track ending data, wherein the initial correction track data sequence comprises multiple pieces of initial correction track data, and the initial correction track data is obtained by performing filtering according to measured motion data and predicted motion data corresponding to the target object; and each piece of initial correction track data in the initial correction track data sequence is adjusted according to the track starting data and the track ending data to obtain a target correction track data sequence, wherein the target correction track data sequence is used for determining a target track corresponding to the target object. Through the method, the accuracy of the track data of the target object can be improved.

An embodiment of the invention relates to an accurate positioning method for edgewise cleaning by an unmanned cleaning vehicle. The method comprises steps of: receiving IMU data, pulse data of a wheelspeed sensor, and laser positioning or GPS positioning data; monitoring a vehicle state according to the IMU data and the pulse data of the wheel speed sensor, and if the vehicle state meets a presetstatic condition, calculating an initial horizontal attitude angle of the vehicle and a power-on initial zero offset value of a three-axis gyroscope according to acceleration data output by an IMU, so as to complete initialization; then, updating attitude quaternion by using angle speed output by the IMU and updating speed and position by using acceleration data output by the IMU, establishing acorresponding filter model and completing prediction, when data of the wheel speed sensor, laser positioning or GPS positioning is received, filtering to obtain error correction amount and correctingcurrent quaternion, position and speed, so as to obtain accurate attitude information of the vehicle at the moment, performing dead reckoning by using the wheel speed sensor, so as to obtain a position and an attitude of the vehicle in a navigation coordinate system at present.

The invention discloses a calibration device and a method for carrying out calibration on a transfer function in a monitoring device. The method comprises the steps: setting m parameters of the transfer function as parameter values of first iteration; carrying out at least one iterative process; in a jth iterative process, if a calculated error evaluation value s is smaller than an evaluation target value according to AD1-ADn, Rxp1-Rxpn, and a parameter value of jth iteration, confirming the parameter value of the jth iteration as a calibration result; if not, adjusting the parameter value of the jth iteration according to a shrinkage algorithm, obtaining a parameter value of j+1th iteration, and continuing the next iterative process, wherein the Rxp1-Rxpn are n index values of a monitored object, and the AD1-ADn are n sampling values. Due to the fact that the shrinkage algorithm is adopted to carry out iterative calculation on the parameters of the transfer function, the process of missing solution of equations is avoided, the method can be applied to situations of a non-linear transfer function and a non-least-square error evaluation function, and accordingly the calibration method has wide application situations.

The invention discloses a machine tool thermal error test point optimizing and modeling method. The method includes the following steps that (1) thermosensitivity analysis is performed on a spindle, and quantitative analysis is preliminarily performed in combination with the actual size of the spindle; (2) cut points are arranged in a thermosensitive area according to the golden section method, thermal error synchronous tests are performed, and the optimum thermosensitive area is determined with the relevancy between thermal deformation at different temperatures; (3) points are evenly distributed in the thermosensitive area for tests, and sample data are superposed correspondingly according to a certain superposition rule, cumulative summation is performed, a regression equation is established, and parameters of a regression model are estimated. Through the method, the optimum point distribution area can be found fast and conveniently, and the problems that traditional point distribution according to experience is redundant in data, low in reliability and the like are solved; a cumulative regression algorithm is adopted for modeling, error items can be not directly processed, and thus the method has the advantages of being simple, visualized, convenient for a computer to implement and the like and has higher efficiency and precision than the least square method.

The invention discloses a flax-to-cotton blending ratio detecting method, which is characterized by the following: selecting the detected blending ration flax and cotton specimen; detecting the absorption value Aa of cotton solution, Ab of flax solution and A of known blending ratio solution; putting these absorption values in the Lazuli formula to count the ª‡ value of flax-to-cotton mixture; putting the sample mixture in the sulfuric solution; filtering and cooling the solution and to detect the absorption value A; calculating the blending ratio Fa of cotton fiber through Lazuli formula.

The invention discloses a method for rapidly detecting broken rice rate based on image recognition and belongs to the technical field of food detection. A rice appearance quality detection device provided by the invention is uniform in size specification of acquired images and relatively high in recognition rate and solves the problems that accuracy rate is low, subjectivity is strong, efficiencyis low, randomness is high and an error is big during manual detection. The method disclosed by the invention obtains an optimal threshold value 0.68 / 0.40 for determining broken rice and small brokenrice after threshold value optimization is performed on a detection system; and broken rice content of rice is determined at the threshold value, and compared with a manual process, an absolute errorof a determination result is less than 0.5%.

The invention discloses a weight calibration device for a large-mass comparator and relates to the field of measurement. The weight calibration device for the large-mass comparator comprises a base, wherein a weighing tray for weighing weights is arranged on the base, a supporting structure, wherein the supporting structure is arranged on the weighing tray and a supporting gap is arranged on the supporting structure and the width of the supporting gap is smaller than the diameter of the weight, a loading frame, wherein the loading frame is detachably connected to the base and the loading framecomprises a loading table for supporting the weight. When the loading frame is arranged on the base, the loading table is arranged in the supporting gap, and the distance between one side of the loading table which is far away from the base and the base is smaller than the distance between one side of the supporting structure which is far away from the base and the base. According to the weight calibration device for the large-mass comparator, the influence of the loading frame on the calibration process is reduced, namely, the possibility of absolute error generation is reduced, and the accuracy and stability of the comparator weight calibration are improved.

The invention discloses calculation method development for marking-off in the process of processing plate parts, which comprises the following steps of: (a) analyzing by using a draft, and determining a position relation among geometrical elements according to a drawing; (b) establishing a form coordinate system; (c) establishing a development coordinate system; (d) listing a development calculation formula; (e) calculating parameter values according to the calculation formula in the step (d); and (f) drawing a development drawing according to the parameter values calculated in the step (e). The calculation method development for marking-off in the process of processing plate parts has the advantages that: the regularity is high; the complicated middle drawing operation is avoided, the dependence on field, equipment and the like is reduced, and the development drawing can be drawn without gauge by rarely using a ruler, so the labor intensity of an operator is reduced; the calculation formula has universality; and the calculation method development has high adaptability, precision, feasibility and practicability.

The invention provides a modeling and fault early warning method and system for a dry-type reactor, and the method comprises the steps: building an electromagnetic-circuit two-dimensional analysis model of the dry-type reactor through Maxwell, enabling the model to comprise a finite element magnetic field model and a circuit model, and obtaining the packaging loss through the calculation of the model; calculating temperature field and flow field distribution of the reactor by taking the encapsulation loss as a heat source of a three-dimensional fluid-temperature field, and performing multi-physical field model fusion by adopting a loop iteration algorithm to establish a three-dimensional fluid-temperature field finite element model; carrying out order reduction on the three-dimensional fluid-temperature field finite element model by adopting a PSO-SVM fusion algorithm; and on the basis of the model establishment, various turn-to-turn short circuit fault simulation is carried out to realize fault identification and early warning discrimination. According to the modeling and fault early warning method, the early warning accuracy is improved, and the method can be widely applied to the field of design and early warning of dry-type reactor equipment.

The invention discloses a detection method of total content of fructo-oligosaccharide in formula milk / milk powder. The detection method realizes enzymolysis treatment of the fructo-oligosaccharide by utilizing an enzymolysis method, and moreover realizes detection of the total content of the fructo-oligosaccharide in the formula milk / milk powder by adopting a universal high performance liquid chromatography-evaporative photodetector by selecting a specific chromatographic condition. The detection method has the advantages that the trouble that a special ampere detector for ion chromatography impulse is required to be used in the existing national standard method GB5009.88-2016 is overcome; the equipment cost is low; the universality is high; and the generalization performance is high. Compared with a detection result of the special ampere detector for the ion chromatography impulse used by the method GB5009.88-2016, an error is less than 5%.

The invention relates to a marine diesel engine torsional vibration signal processing method. The method includes the following steps that: intensive resampling is performed on a marine diesel engine signals, and zero position detection is performed; and interpolation processing is performed on obtained signals, zero position detection is performed on sampling signals, a transformation point is searched, a zero-crossing time point is determined, and interpolation processing iteration is performed to obtain high-sampling marine diesel engine torsional vibration signals. According to the method of the invention, intensive resampling can be performed on obtained torsional vibration signals; a signal interpolation starting point is determined through the zero position detection, so that interpolation processing can be performed on the signals, and missing points existing in the signals are compensated; and the high-sampling marine diesel engine torsional vibration signals can be obtained through a plurality of times of signal zero position detection and interpolation processing, and the absolute error of the signal is smaller than 5%.

The invention discloses a system and a method for adjusting ink control information. The system comprises a printing ink control information observing and controlling driver, an image color data observing and controlling unit, an image color data converting unit and an ink control information adjusting and outputting unit. The printing ink control information observing and controlling driver is used for selecting an observing and controlling target; the image color data observing and controlling unit is used for observing and controlling the image color reflection information data of an advance sheet and a printed sheet and converting the data into image RGB color data; the image color data converting unit is used for converting the image RGB color data so as to obtain ink amount control information reference data and contrast data as well as obtaining the ink control information data by contrast calculation; and the ink control information adjusting and outputting unit is used for adjusting the ink control information data and transmitting the data after being adjusted to a printer server. The system and the method for adjusting ink control information solve the problem of hard color consistency between the advance sheet and the printed sheet during printing operation and leads the color deflection existing between the advance sheet and the printed sheet to be adjusted by users, thereby obtaining objective printing image color data and leading the colors of the printed sheet and the advance sheet to maintain a more consistent state.

The invention provides an oil reservoir automatic history fitting method based on a generative adversarial network, and the method comprises the steps: carrying out the collection of data, and forminga data set through permeability field data and production data; preprocessing the data set, and dividing the data set into a training set, a verification set and a test set; training a generative adversarial network model by using the training set data, and selecting an optimal model for storage by using the verification set data; reading the stored optimal model, inputting test set data, and generating a corresponding permeability field; performing numerical simulation on the permeability field data generated in the previous step to obtain production data b, comparing the production data b with production data B corresponding to a real permeability field in the test set, and performing result verification; and applying the model which is verified to be qualified through a result to actual oil well geological condition prediction. According to the method, an agent model or expert experience is not needed, the mapping relation between static parameters (permeability fields) and dynamicproduction data is found by training the generative adversarial network, and the geological condition is obtained through the oil well production data.

The invention discloses a spectrum online blood glucose analyzer and an insulin pump control method, and relates to an insulin pump therapeutic instrument for diabetic patients. The spectrum online blood glucose analyzer and the insulin pump control method are invented mainly for solving problems that an existing insulin pump can only reflect a blood glucose condition at the time of blood samplingand cannot continuously measure a blood glucose level. A blood glucose concentration in a human body is analyzed and measured on line in vitro by utilizing a spectrum on-line analysis technology, andan insulin infusion dosage is adjusted and a treatment scheme is optimized according to continuous detection and analysis data of an on-line analyzer in combination with artificial intelligence systems such as remote medical support and the like. The data are transmitted to a central module through a wireless data network, the central module controls a program controller PLC, and then the PLC regulates and controls operation of an insulin pump. The insulin pump, insulin storage bottles and the program controller PLC are integrated in a portable box body, and two or more insulin storage bottles are arranged in the box body, so that the invention has advantages that online switching of insulin types can be carried out at any time according to treatment requirements, and an optimal treatmenteffect is achieved.

The invention provides a frequency deviation estimation method and a device, and communication equipment. The frequency deviation estimation method comprises the following steps: acquiring at least three sections of received sampling data corresponding to a known channel estimation sequence; according to each section of received sampling data and the corresponding channel estimation sequence, obtaining a phase elimination sequence corresponding to each section of received sampling data; carrying out difference calculation on any two sections of phase elimination sequences to obtain a difference result corresponding to the two sections of phase elimination sequences, and obtaining a difference distance of the difference result according to a time interval between the two sections of phase elimination sequences; adding the differential results of all the same differential distances to obtain an accumulated differential item of each differential distance; performing weighted summation onall the accumulated differential items with different differential distances to obtain a mixed differential item; and estimating the frequency deviation between the data sender and the data receiver according to the mixed differential item. According to the method, the estimation accuracy of the frequency deviation can be improved under the condition of obtaining the same received data.

The invention discloses a mechanism and brain-like intelligence combined online soft measurement method for quality of coal as fired of a power plant.. The method comprises the steps of collecting monitoring data of 190 conventional monitoring points in real time; and extracting original principal component characteristics of the monitoring data, inputting the original principal component characteristics into a pre-established online soft measurement model of the coal as fired of the thermal power plant, and outputting soft measurement values of online element components and industrial components of the coal as fired. Under the condition of not adding any hardware facility, real-time and accurate online soft measurement of the quality components of the coal as fired can be realized, and areal-time online basis can be provided for combustion optimization, intelligent control and decision making of a thermal power plant; in addition, the method utilizes real-time data of conventional monitoring points of a thermal power plant to realize soft measurement of coal quality of as-fired coal and five element components and four industrial components at the same time; wherein the soft measurement absolute error of each component is less than 1%, and the soft measurement time is less than 1 second.

The invention relates to the technical field of tea withering degree detection methods, in particular to a nondestructive detection method for withering degree indexes of black tea. The nondestructivedetection method comprises the following steps of respectively placing tea leaves withered to different degrees under an industrial camera to shoot sample pictures, detecting withering degree indexes, preprocessing the shot sample pictures, establishing a convolutional neural network database by using withered leaf picture information and withering degree index data, classifying the withering degree indexes in the database, and establishing a black tea withering degree index quantitative prediction model according to confidence coefficients obtained by classifying the withering degree indexes. According to the nondestructive detection method, a black tea withering moisture quantitative prediction model based on the convolutional neural network confidence coefficient is established, and the model has excellent generalization performance and stability and can be used for rapid and nondestructive detection of black tea withering moisture.

The invention provides an aircraft engine cable intermittent fault detector and a detection method thereof, and the detector comprises: a case which is provided with a power interface, a detection interface, and a display device; a control module which is arranged in the case and is used for assisting and realizing a detection function; a detection probe accessory, wherein one end of the detectionprobe accessory is connected to the case, the other end of the detection probe accessory provides detection connection, and the detection probe accessory is matched with the control module to achievethe aircraft engine cable intermittent fault detection function. The detector is beneficial to accurately detecting various types of cable intermittent faults of the aircraft engine, and eliminates potential safety hazards of the engine.

The invention discloses a construction method of a boundary forest model, a multi-working-condition soft computing model updating method for a complex industrial process and an application thereof, belonging to the field of computer application. In order to solve the problem that prediction values are unreliable due to the fact that leaf nodes of a tree integration model easily generate blank areas in an output range, when a current training set under a certain working condition is known, the construction method comprises the steps: setting different leaf node minimum sample numbers, and establishing K tree integration models with different leaf node boundaries by using different leaf node minimum samples; predicting output values of all samples in the current training set by using a treeintegration model, and forming a prediction matrix by the predicted output values; according to the prediction output value of the prediction matrix, constructing a correlation matrix of the prediction output value and a real output value; and calculating a fusion weight vector, using the weight vector, and fusing the tree integration models with different boundaries into a boundary forest model,so that the leaf nodes of different tree models cover each other, and the blank area of a single tree on an output boundary is filled, and a reliable prediction value is generated.