111results about How to "Eliminate random errors" patented technology

The invention discloses a method for detecting mutation information in a multiplex amplification sequencing product of a genome. The method comprises steps as follows: sequencing data are subjected to quality assessment and preprocessing; a recognizable sequencing sequence is selected for sequence assembling; the recognizable sequencing sequence or a sequence obtained through assembling is compared with a reference gene sequence, and preliminary variation information is obtained; fine calibration of sequence variation is performed according to different types of conditions; a calibrated sequencing fragment is obtained; the homozygosis or heterozygosis state of a target fragment is obtained according to the type of the sequencing fragment with the highest abundance; finally, the mutation information in the multiplex amplification sequencing product of the genome is obtained. By means of the method, the amplification product can be rapidly, efficiently and accurately recognized, and the calculation resources are saved; the sequence assembling process is compatible, and the problem of reduction of the quality value of basic groups produced in the sequencing process can be effectively solved; the homozygosis/heterozygosis state of variation information can be more effectively and stably judged, and random errors introduced in the PCR (polymerase chain reaction) process and the sequencing process are eliminated.

The invention discloses a method for detecting boll opening of cotton based on image detection. The method specifically comprises two stages, namely a training stage for counting the change rule of a cotton region in a cotton field image in a Lab color space through history image data, and a detection stage for detecting a real-time cotton field video image by using the change rule of cotton counted in the training stage in the Lab color space. The method comprises the following specific steps of: (1) detecting a single cotton image, detecting a candidate cotton region in the image according to a counting result and generating a binary result image; (2) marking and de-noising a communication domain, marking the binary result image and removing small noise interference by setting an area threshold value of the communication domain; (3) making a comprehensive judgment, voting each candidate region by using detection results at different moments of each day, selecting a stably existing region serving as the final cotton region detection result and further removing the interference of random noise; and (4) outputting a result image. By adopting the method, the influence of illumination is effectively overcome by using the Lab color characteristic of cotton and the continuity of images on the same day, and the presence of cotton in a cotton field image is detected correctly.

An embodiment of the invention relates to the technical field of automatic driving, and discloses a vehicle, and a method and a system for automatically calibrating zero offset of a steering wheel ofthe vehicle. The method includes judging whether the vehicle is in straight driving states in current sampling time intervals or not; determining that the current sampling time intervals are current calibration time intervals if the vehicle is in the straight driving states, and acquiring steering angles of the steering wheel of the vehicle when the vehicle is in the straight driving states; acquiring historical zero offset calibration results; calculating real-time zero offset calibration results of the steering wheel of the vehicle according to the historical zero offset calibration resultsand zero offset calibration results, which correspond to the current calibration time intervals, of the steering wheel of the vehicle. The steering angles are used as the zero offset calibration results, which correspond to the current calibration time intervals, of the steering wheel of the vehicle. The vehicle, the method and the system in the embodiment of the invention have the advantages thatthe zero offset of the steering wheel of the vehicle which is currently automatically driven can be automatically calibrated by the aid of the method and the system, and the zero offset measurement accuracy of the steering wheel of the vehicle can be improved.

A chaos impulse list ultrasonic distance test method and equipment belong to ultrasonic distance test technology field. (1) Create the breadth-modulating list of chaos impulse list. (2) Create and send the ultrasonic by excitation ultrasonic energy-exchanging implement to the breadth-modulating list of chaos impulse list, and save the breadth-modulating list of chaos impulse list. (3) Accept the echo signal of the need test object with the said ultrasonic energy-exchanging implement. (4) Operate the accepted echo signal with the former chaos impulse list to confirm the echo time and the distance to the object. The ultrasonic distance test by this method and implement has strong anti-jamming ability, better real time quality and high precision.

The invention discloses a device and a method for compensating for detection polarization fluctuation of rotation angles of linearly polarized light in an online manner. The device comprises an optical module and a measurement control module. The optical module comprises a reference light path and a signal detection light path and mainly comprises a laser device, a polarizer, a liquid crystal variable-phase retarder, a photoelastic modulator, a 1/4 wave plate, a to-be-measured atom gas chamber sample, polarization beam splitting prisms and the like; the measurement control module comprises balance differential detectors, a liquid crystal driver, a photoelastic controller, a phase lock amplifier and a data acquiring and processing unit. The device and the method have the advantages that error sources of various devices do not need to be differentiated for optical detection systems with the multiple complicated polarization devices, only characteristics of input ends and 'black box' type processing modes for signals of output ends need to be considered, accordingly, compensation and correction for eliminating detection random errors of the rotation angles of the light in real time can be implemented on the basis of photoelastic modulation, and the signals can be stably detected in a high-precision manner for a long time.

The invention belongs to the technical field of satellite navigation, and in particular relates to an apparatus for time synchronizing based on multi-satellite common view and a [alpha]-[beta] filtering and a method thereof. The apparatus includes connected time synchronous modules which are mounted inside two pseudo satellites, wherein the time synchronous module includes: a multi-channel receiver module, a communication module, an information processing and clock correcting module. The method includes: through collection data of the two pseudo satellites, obtaining the position of the satellite tested and pseudo ranges with respect to the pseudo satellites A and B, obtaining an elevation angle of the satellite through calculation, and conducting weighting and averaging with the sine value of the elevation angle as the weight, conducting the [alpha]-[beta] filtering in combination with the mathematical model for clock error, further correcting clock errors, eventually obtaining a more accurate clock error estimation value, correcting the clock error of the pseudo satellite which needs synchronization based on the clock error estimation value, and at last achieving the time synchronization between the two pseudo satellites. The embodiments of the invention can eliminate random error in observed quantity, increase precision of time synchronization, and have a stronger ability than single channel common-view time synchronization method in terms of anti-interference.

The invention discloses a method for measuring related parameters of sensitivity, linearity and dark noise of a charge coupled device (CCD) chip, and mainly solves the problems of low measurement precision and incomplete measurement parameters in the prior art. The method comprises the following steps of: selecting a wavelength eta corresponding to the moment that the quantum efficiency of the CCD chip is maximal, and setting a tunable wavelength monochromatic uniform light source system to generate monochromatic light with the wavelength eta; selecting a series of integration time, and controlling the CCD chip to shoot image information and upload the image information to a computer by taking the integration time as parameters; selecting needed images by using corresponding computer software, and calculating the mean gray value mu, the time domain variance sigma<2> of the images and a system gain K; and calculating a saturation level mup.sat, a signal-to-noise rate (SNR), an absolute sensitivity threshold value mup.min, a dynamic response range DR and a nonlinearity error LE by using the acquired parameters. The method for measuring the related parameters of the sensitivity, the linearity and the dark noise of the CCD chip has the advantages of high parameter measurement precision, high stability and complete measurement parameters.

Provided in the invention is a measurement apparatus and method of camera shutter delay time. A single-chip microcomputer, a display, and a camera shutter control line are arranged. The single-chip microcomputer I connected with the display and the camera shutter control line; and the display is arranged in a viewfinder range of the camera. The single-chip microcomputer executes the following flow: step one, starting a counter and outputting and displaying an accumulated result of the counter to the display; step two, carrying out delaying to wait for preparation of the camera; and step three, determining whether a preset number of times for measurement is reached; if so, finishing the work; and if not, resetting the counter and sending an exposure instruction to the camera by the shutter control line, thereby enabling the camera to shoot the display to obtain current shutter delay time of the camera; and returning to the step two until reaching the number of times for measurement. On the basis of the technical scheme, the delay time parameter of the camera shutter can be measured rapidly and accurately, thereby guaranteeing accuracy of subsequent image data processing.

The invention provides a mini-sized three-dimensional topography measurement system and a mini-sized three-dimensional topography measurement method based on LED microscopic fringe projection. A high contrast interference fringe can be generated by directly using a simple device, and weak coherent light (LED) is used as an illumination light source, and because a coherent length is short, interferences of scattered stray light of a light beam during a transmission process on a receiving screen are prevented, and therefore influences of coherent noises are inhibited, and vertical measurement precision of the system and the repeatability of the measurement are improved. A complicated optical path is not required for light beam compression, and the mini-sized three-dimensional topography can be measured directly. The fringe acquired by using LED shearing interferences has the high fringe contrast, and a price of an LED light source is cheap, and compared with a DLP projector, a cost of an optical measurement system is reduced, and then batch production is facilitated. The mini-sized three-dimensional topography measurement system and the mini-sized three-dimensional topography measurement method have advantages of simple optical path adjustment, cheap prices of adopted devices, easy popularization, and ability of acquiring high contrast fringe.

The invention discloses a calibration method for a digital multimeter. The measuring range is segmented, a corresponding calibration coefficient is worked out through a measured value and a standard value of a standard workpiece to be measured corresponding to N segmentation points Rn, and a zero offset value, a measured value of an unknown workpiece to be measured is modified through the calibration coefficient, and the applicable range of the calibration coefficient is determined according to the segmentation points Rn. Through the calibration method for the digital multimeter, the precision of the digital multimeter can be improved. Measured values in the region nearby the segmentation points of the applicable range of the calibration coefficient can be modified with the linear spline interpolation method, and the precision is further improved. Besides, the measured values can be processed in advance through average smoothing filtering, and therefore random errors are eliminated.

The invention discloses a method for measuring the CCD (Charge Coupled Device) chip dark current and double temperature constant. The method is realized by the following steps of: arranging a CCD chip in a dewar flask temperature control room, and configuring a reference temperature such that the CCD chip works at the reference temperature, wherein the temperature control room is sealed and light-proof; controlling the CCD chip to shoot an image through a control circuit, and uploading the information of the image to a computer; calculating an average gray value of the obtained image; drawing a fitting curve by utilizing the average gray value of the image and corresponding integration time to obtain a dark current; and finally calculating the double temperature constant by measuring the dark current at a plurality of different temperatures. The method disclosed by the invention has the advantages of high parameter measurement precision and good stability, and is suitable for precise measurement of the dark current and the double temperature constant of the CCD chip.

The invention provides a method for testing the total isotropic sensitivity (TIS) of a mobile terminal, which comprises the following steps of: obtaining a functional relation curve between antenna port input power (PInAnt) of a signal channel to be tested and a bit error rate (BER), wherein BER=f(PInAnt) or PInAnt=f-1(BER); carrying out phi polarization and theta polarization test according to the functional relation curve between the antenna port input power and the bit error rate to obtain equivalent isotropic sensitivities, i.e., EIS theta (theta i, phi j) and EIS phi (theta i, phi j) of a space position (theta i, phi j); and after testing the EIS theta (theta i, phi j) and the EIS phi (theta i, phi j) of all the space positions, calculating to obtain the TIS of the signal channel to be tested. According to the embodiment provided by the invention, the test speed of the TIS can be effectively increased on the premise of not losing the test accuracy, so that rapid and accurate TIS measurement is realized.

The invention provides a high-precision multi-rotor aircraft cooperative positioning method and system. The method comprises the steps: selecting a target needing to be located; acquiring informationdata by n unmanned aerial vehicles, the information data comprising parameter information of the unmanned aerial vehicles, target sight angle information and distance information between the unmannedaerial vehicles and a target; and processing the information data to obtain an estimated value of the target position. According to the method provided by the invention, multiple unmanned aerial vehicles are adopted to cooperatively acquire information, and the installation error between the photoelectric pod and the integrated navigation module is introduced into the least square model, so that high-precision positioning of a long-distance target in a short time is realized under the condition that the precision of an inertial navigation element is relatively low, the positioning precision ishigh, and the time is short.

The invention belongs to the technical field of optical and electronic devices and discloses a method for improving a measurement precision of an ellipsometer. The ellipsometer comprises a light source, a fixed polarizer, a rotary polarizer, a sample, an analyzer and a detector connected orderly, wherein the rotary polarizer and the analyzer rotate synchronously in a ratio of 1:2 at an angular velocity. The ellipsometer can acquire ellipsometry parameters by two self-consistent methods thereby acquiring various optical parameters of a test sample. Traditionally, ellipsometry parameters can be obtained by one of the two self-consistent methods, or ellipsometry parameters obtained by the two self-consistent methods are subjected to averaging. The method provided by the invention is a novel data processing method, realizes combination of the two self-consistent methods and can obviously improve a measurement precision.

The invention discloses a communication cable shielding layer remote grounding resistance measurement device and method. A sine wave signal generator module is configured to generate frequency-adjustable sine signals as a measurement signal source through a DDS technology; an adjustable power amplification module adjusts the size of transmission power of measurement signals according to actual needs; a current sampling module performs sampling and calculation on output current of the measurement signals, a current value of the measurement signals is finally obtained, and grounding resistance calculation is carried out; and a resistance calculation module uses an Ohm law to calculate and obtain the current resistance value through the obtained measurement current value and the power value.

The invention discloses an error correction method of a fluxgate sensor for cable positioning. The error correction method comprises the following steps of modeling a sensor error, simplifying a model, and changing the attitude of the fluxgate sensor to acquire magnetic field data, averaging the measurement data to obtain a total magnetic field reference value, solving an optimal parameter of an error model by combining the acquired magnetic field data and the total magnetic field reference value and using a multivariate function extremum solving method to obtain an error correction model of acertain sensor, and when the cable is positioned, inversing a real magnetic field value by combining the magnetic field value obtained by the sensor and the error correction model. According to the method, other sensors with higher precision do not need to give reference values, the error correction model and parameters of the same sensor do not need to be changed, and the universality of the model is good. The sensor error model obtained in an area without interference is used for data processing during cable detection, the error of the fluxgate sensor for cable positioning is reduced, and the measurement precision is improved.

The invention relates to a pressure gas leak detector for airtight containers, in particular to a pressure gas leak detector which maintains the detection pressure as a required detection pressure value constant during detection. A servo type constant pressure device is adopted to track pressure change, so the leak detector can keep the leak detection pressure unchanged, and can correctly meet the technical requirements of constant-pressure leak detection; and most importantly, the detection result is obtained through direct measurement, and the theoretical calculation is not adopted to replace direct measurement any more, thereby directly eliminating various difficultly controlled or measured theoretical errors, systematic errors and random errors. The precision is only affected by the self-precision of the servo type constant pressure device and a leak detection sensor. The self-precision of the sensor or the servo type constant pressure device is optional according to the design ofmeasured objects, is controlled to be less than 0.5 or 0.1 percent of required values, and can fully meet the using requirement of high-precision leak detection.

The embodiment of the invention provides an airborne distributed POS (position and orientation system) transfer alignment method and an airborne distributed POS transfer alignment device. By the airborne distributed POS transfer alignment method, measured values of deformation displacement and deflection angle, which are obtained by high-precision optical equipment, are introduced for establishingdirect constraint relationships between the two and a position error and a deflection angle in state variables respectively; based on the conventional matching of the orientation and the speed, matching of the position and the deflection angle is added to form new matching of the orientation, the speed, the position and the deflection angle so as to obtain a new measurement equation; through Kalman filtering, random errors of the measured values of the optical equipment are eliminated and more accurate estimation of the state variables of the position error and the deflection angle is achieved, so that the estimation accuracy of the position, the speed and the orientation of a subsystem is improved.

The invention discloses a method and a device for measuring an attitude dip angle of a moving carrier based on a floating point type DSP (digital signal processor). The method comprises the following steps: an IMU (inertial measurement unit) module is arranged on a tested moving carrier, the DSP obtains three types of attitude angle information through real-time collection, analysis and processing, and a virtual oscilloscope is used for recording, displaying and storing dynamic waveforms; the device comprises an IMU, a power supply circuit, a floating point type DSP circuit, an SCI-to-USB (serial communications interface to universal serial bus)communication circuit and an upper computer, wherein the IMU comprises a gyroscope and gyroscope processing circuit and an accelerator and accelerator processing circuit; the gyroscope and gyroscope processing circuit comprise a gyroscope, an ADC (analog-to-digital conversion) circuit, a digital filtering circuit and an IIC interface circuit with FIFO (first in, first out) that are connected with one another in sequence; and the accelerator and accelerator processing circuit comprise an accelerator, an ADC circuit, a digital filtering circuit and an IIC interface circuit with FIFO that are connected with one another in sequence. The method and the device provided by the invention have the advantages that the tracking effect on the dynamic attitude dip angle is good, the real-time performance is high, the accuracy is high, the representation scope is wide, and the data processing efficiency is high.

The invention provides a weight and slope calculation method of a pure electric commercial vehicle based on a three-axis accelerometer, which comprises the following steps of: establishing a control model by acquiring acceleration values of x, y and z axes of the three-axis accelerometer, estimating the mass and slope of the whole vehicle by a forgetting factor recursive least square method. A mass least square estimation model combining vehicle longitudinal dynamics and acceleration sensor signals is provided to accurately estimate the weight and slope of the whole vehicle.

The invention discloses a drop volume measuring device, particularly to a drop measuring device for automatically measuring liquid volume in petrochemical industry. A drop volume detecting device is mounted at a to-be-detected liquid outlet and includes a funnel, a funnel cover, a photoelectric sensor, a level bubble, a mirror and magnetic steel. The to-be-detected liquid outlet is inserted into the eccentric liquid intake opening of the funnel cover and contacted with the liquid collecting wall of the funnel so as to be fixed. The drop drips out of a dripping outlet and falls for a distance, and then the double-peak pulse width produced by drop is measured by the photoelectric sensor, as a result, the liquid volume is measured according to a certain proportional relation.

The invention relates to the field of electronic product production testing, and particularly relates to a dual-mode time service machine. The time service machine comprises a Beidou 2nd generation /GPS dual-mode receiver module, a power supply module, a counting module, a CPU control module and an output module. According to the invention, satellite signals are received by using a Beidou 2nd generation/GPS dual-mode receiver, dual-channel running of a Beidou 2nd satellite and a GPS satellite is ensured, the stability of a signal source is ensured, the counting module selects a constant temperature crystal oscillator module, a Beidou 1pps random error mathematic model is built, and a Beidou 1pps random error is corrected online, so that a random error of Beidou second pulse signals can be effectively eliminated, and the time precision is improved. Meanwhile, the power supply module of the dual-mode time service machine utilizes a photovoltaic effect of solar cells, thereby achieving effects of energy conservation, stable power supply and convenient installation.