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41results about How to "Avoid Calculation Bias" patented technology

Dynamic compensation method for ultrasonic flow meter

The invention discloses a dynamic compensation method for an ultrasonic flow meter. The dynamic compensation method comprises the step of measuring time dynamic period compensation and further comprises the step of conducting fluid density compensation, the step of conducting time difference temperature compensation of ultrasonic countercurrent spreading time and ultrasonic fair current spreading time, the step of looking up a calibration coefficient dynamically according to a calibration coefficient lookup table established in advance and the step of calculating the flow of multistage dynamic compensation, and therefore measuring time dynamic period compensation is conducted on the problem that ultrasonic spreading time measurement has deviation due to the water attack effect brought by instant opening and closing of a valve or residual bubbles in a pipeline; furthermore, compensation is conducted on the liquid density change caused by the temperature; temperature compensation is conducted on the time difference benchmark treating the influences of the temperature change of an element in a circuit box, the lookup table is established on the calibration coefficient without a constant value, and dynamic looking-up is conducted during flow calculation.
Owner:BEIJING INST OF CONTROL ENG

Bridge dynamic impact factor extraction method

The invention relates to the technical field of civil engineering and discloses a bridge dynamic impact factor extraction method to effectively solve the problem of determination of a maximum static value. The method can obtain a more accurate and reasonable bridge dynamic impact factor value, and provides reference for bridge design and management and maintenance and the like. The method comprises the following steps: obtaining dynamic response of a measurement point on a bridge; carrying out piecewise polynomial fitting on the quasi-static portion in the bridge dynamic response, and carrying out superposition fitting on the fluctuation portion in the bridge dynamic response through a series of sine curves; carrying out fitting calculation based on the least squares principle to obtain influence line information reflecting bridge static characteristics; determining a tire-road surface contact force distribution model and a corresponding contact force distribution function; and then, on the basis of the actual bridge inherent influence line information obtained through fitting, and with the contact force distribution function being combined, calculating maximum static response when a vehicle passes the bridge, and calculating the bridge dynamic impact factor.
Owner:CENT SOUTH UNIV

Method for dynamically estimating noise through radar echo and meteorological radar system

The invention discloses a method for dynamically estimating noise through radar echo and a meteorological radar system and solves a technical problem of non-high meteorological prediction accuracy existing in a meteorological radar system in the prior art which can not acquire dynamically-changed system noise in real time. The method comprises steps that a radar echo signal is converted into an IQ sequence signal, Fourier transform of the IQ sequence signal with the sampling number of N in a kth distance database is carried out, a power spectrum coefficient is calculated to acquire power spectrums sp, the k is a positive integer; the power spectrums sp are ordered in an ascending order, and the ordered power spectrums sp are marked as S; variables mc and b0 are set, during initiation, the mc is made to be equal to the N, and the b0 is made to be 0; when it is determined that the mc is greater than 2, and the b0 is smaller than 1, cycle calculation is carried out according to formulas described in the specification; after each cycle calculation, whether the b1 is not greater than 0 is determined, and the present mc is recorded; if the b1 is not greater than 0, the system noise is estimated by employing the present mc, and thereby the system noise of the kth distance database is acquired according to a formula described in the specification.
Owner:BEIJING METABTAR RADAR

Searching method and device in dialogue realization and computer readable storage medium

The invention discloses a search method and device in dialogue realization and a computer readable storage medium. The method comprises the following steps: obtaining a question statement requesting dialogue; retrieving the question sentences in inverted index information constructed by taking the words as granularity to obtain matched words; positioning a question under a knowledge point pointedby the positive index information through question identification information mapped by words matched with the question statements in the reverse index information; and according to the positioned question, obtaining an answer under the knowledge point as a question statement request from positive-row index information constructed by taking the knowledge point as granularity to perform conversation. In this way, the inverted index information is constructed by taking the words as the granularity, the problem statements are matched by taking the words as the granularity, and each word in the problem statements is matched in the inverted index information, so that the problem of calculation deviation in the matching of the problem statements is avoided, the difficulty of obtaining answers indialogue realization is effectively reduced, and the accuracy of the answers is improved.
Owner:TENCENT TECH (SHENZHEN) CO LTD

Acquisition methods of linear density coefficient curve and standard tuft curve

ActiveCN106769652AAvoid Calculation BiasEliminate the problem of larger position deviationSpecific gravity measurementOptical measurementsLinear density
According to the technical schemes, the invention provides an acquisition method of a linear density coefficient curve, a positioning method of a double-end tuft center line and an acquisition method of a standard tuft curve. The methods have the advantages that a calculation deviation of a Lambert-Beer optical algorithm is eliminated, and the problem that in existing optical measurement, the deviation of the position where the fiber density is higher is larger is solved; by means of the novel sampling, image measurement and signal analysis method, the problems that noise is generated in measurement signals, and a tuft start line is difficult to recognize can be avoided, the accurate position of the tuft start line and accurate information of the highest linear density are obtained, and the complete and accurate tuft curve and linear density curve are calculated.
Owner:DONGHUA UNIV

Method and device for optimizing instantaneous dynamic of LLC resonant converter load

The invention discloses a method and device for optimizing the instantaneous dynamic state of an LLC resonant converter load. Firstly, an actual test of a specific point is carried out on the LLC resonant converter; discrete points related to the LLC switching frequency, the input voltage, the output voltage and the output current are obtained; and fitting is carried out to obtain an optimal objective function of the LLC switching frequency, and then through dynamic load switching judgment, a final output PID result of the voltage loop controller linearly approaches an expected output value ofthe optimal objective function when a load suddenly changes. An effective LLC switching frequency target function is obtained through a simple fitting mode, and the PID output result of the voltage controller linearly approaches the expected value of the LLC switching frequency during dynamic load switching. According to the method, the calculation deviation and a large quantity of calculation caused by LLC small signal model modeling are avoided, and the change speed of the LLC switching frequency is increased, so that the dynamic response speed of the LLC is increased under the condition that the hardware cost of the system is not increased.
Owner:SHIJIAZHUANG TONHE ELECTRONICS TECH CO LTD

Genomic microsatellite wide-area length distribution estimation method considering tumor purity factors

The invention discloses a genomic microsatellite wide-area length distribution estimation method considering tumor purity factors. The method includes the steps of completing data feature extraction;finding out microsatellite candidate regions; using a clustering algorithm to filter ignored microsatellite candidate regions; traversing read segments of the regions and performing segmentation; estimating the tumor purity of a given sequencing sample; estimating the length distribution parameter of the tumor tissue microsatellite; using the average length distribution of the long microsatelliteto reflect its overall length distribution; estimating the average length of the microsatellite based on the coverage containing the microsatellite specified window, then iteratively estimating the coverage of the specified window using the updated microsatellite mean length, and completing the detection of the pure tumor sample long microsatellite; and determining the long tumor microsatellite state to complete the wide-area length distribution estimation. The invention solves the calculation deviation caused by the purity problem of the tumor sample of the input data, breaks the limitation of the sequencing read segment length on the length of the detectable genomic microsatellite, and realizes the wide-area length detection.
Owner:XI AN JIAOTONG UNIV

Frequency detection method and device, electronic equipment and storage medium

The invention provides a frequency detection method and device, electronic equipment and a storage medium, and relates to the technical field of sensors, a plurality of vibration signals are obtained through a plurality of sensors, a filter bank is adopted to filter the plurality of vibration signals, a plurality of filtered analog signals are obtained, analog-to-digital conversion is performed on the plurality of filtered analog signals, and a frequency detection result is obtained. The method comprises the following steps: acquiring a plurality of digital signals, respectively determining the maximum amplitude frequency corresponding to each digital signal in the plurality of digital signals, and determining a target frequency value based on the maximum amplitude frequency corresponding to each digital signal. Signals are acquired based on a plurality of sensors, and finally, a plurality of maximum amplitude frequencies are used for comprehensive calculation to determine a target frequency value, so that the signal acquisition error of a single sensor and the calculation deviation caused by different contact degrees of a to-be-detected object and the single sensor are avoided.
Owner:SHANGHAI ELECTRICGROUP CORP

Magnetic resonance coil position determination method and device, and magnetic resonance imaging system

The invention discloses a magnetic resonance coil position determination method and device, and a magnetic resonance imaging system. The method comprises the following steps of collecting magnetic resonance signals received by a coil in pre-scanning and determining projection data of the coil; determining an initial center of gravity position of the coil according to the projection data and a corresponding gradient distortion correction factor; calculating an offset of the initial center of gravity position relative to a physical center of gravity of the coil according to a physical structuralparameter of the coil and a coil channel receiving the magnetic resonance signals in the coil; and migrating the initial center of gravity position for the offset to obtain the physical center of gravity position of the coil. In the invention, a calculation speed is fast, and interferences of a marker on the magnetic resonance signals are avoided; and a calculation deviation caused by signal distortion losses and the like when the coil is at an imaging edge is solved, and accuracy of coil positioning is improved.
Owner:SHANGHAI NEUSOFT MEDICAL TECH LTD +1

Method and device for calculating fatigue life of suspension bridge sling

The invention provides a method and a device for calculating the fatigue life of a suspension bridge sling. The method comprises the following steps: collecting the vehicle load data of a suspension bridge within preset days to reconstruct the vehicle load flow of the suspension bridge sling every day; establishing a three-dimensional space finite element model of the suspension bridge, and basedon the three-dimensional space finite element model, calculating the internal force of the sling under the action of dead load and obtaining the continuous influence surface of the internal force of the sling; loading the reconstructed vehicle load flow of every day to the continuous influence surface of the internal force of the sling to obtain the internal force time travel curve of the sling every day generated by the vehicle load; and according to the internal force time travel curve and the internal force under the action of the dead load, obtaining the fatigue damage of the sling every day, and determining the fatigue life according to the fatigue damage of the sling every day within the preset days. With adoption of the method, the calculation deviation caused by the randomness of the vehicle load data within a short period is avoided.
Owner:BEIJING UNIV OF CIVIL ENG & ARCHITECTURE

Feature fitting-based visual inspection method for substation instrument and equipment inspection

The invention discloses a feature fitting-based visual inspection method for substation instrument and equipment inspection. With feature fitting-based instrument pointer positioning technology adopted, on the basis of the circular projection, edge statistics and fitting analysis of pointer edge features, two included sides of a pointer and the intersection point of the two included sides of the pointer are calculated; and during scale value calculation, linear interpolation is performed on two scales which are the closest to the pointer. With the method of the invention adopted, a current scale value can be the accurately estimated, and scale value calculation deviation caused by the positioning deviation of the center of an instrument or image tilt can be avoided.
Owner:杭州蓝雪科技有限公司

Method suitable for positioning transformer substation electrical apparatus partial discharge space

A method suitable for positioning a transformer substation electrical apparatus partial discharge space belongs to the high-voltage insulation measuring technology and application field. The aim of the invention is to adopt a method suitable for positioning a transformer substation electrical apparatus partial discharge space to process signals of ultra-high frequency electromagnetic wave with improved energy accumulation function so as to avoid calculation deviation due to iterative algorithm depending on initial values. The method of the invention comprises steps: after collecting the ultra-high frequency electromagnetic wave signals, using the improved energy accumulation function to process the signals; drawing a curve line of the improved energy accumulation function based on the improved energy accumulation function; confirming the signal collecting moment of sensors; using four sensors to receive UHF signals of partial discharge radiation and simultaneously record at the starting time; acquiring an equation based on coordinates of a partial discharge source and coordinates of the sensors; acquiring two independent linear equations of the partial discharge coordinates related to unknown numbers; and acquiring two groups of results. In these two groups of results, only one result meets the no-linear equations; and the values are the coordinates of the partial discharge source. By adopting the method provided herein, the calculation deviation due to iterative algorithm depending on the initial values is avoided.
Owner:NORTHEAST DIANLI UNIVERSITY +2

Abnormal sampling point processing method and device based on waveform amplitude calculation feedback analysis

PendingCN114089034ADoes not cause protection refusalImprove reliabilityFrequency analysisAlgorithmEngineering
The invention discloses an abnormal sampling point processing method and device based on waveform amplitude calculation feedback analysis. The method includes: based on an instantaneous value data window of an original sampling point of one cycle, calculating the waveform amplitude of the alternating quantity externally accessed by a protection device and feeding back the calculation result to a calculation module, so as to determine the threshold value of the abnormal point in the data window of the cycle according to the calculation result; comparing the instantaneous values of all original sampling points in the current cycle data window with the threshold value of theabnormal point, analyzing the matching reasonability between the two values, and if the instantaneous value of a certain sampling point exceeds the abnormal point threshold value, judging that the sampling point is an abnormal sampling point value; and if the number of the abnormal sampling points in the current cycle does not exceed the standard, correcting the abnormal point value, recalculating the waveform amplitude, and if the number of the abnormal sampling points exceeds the standard, judging that the calculation is invalid. According to the invention, protection maloperation caused by an instantaneous abnormal sampling point can be avoided, normal protection action during a fault is not influenced, and the reliability of the device is improved.
Owner:STATE GRID ZHEJIANG ELECTRIC POWER CO LTD HANGZHOU POWER SUPPLY CO +2

An Onboard Energy Scheduling Method Based on Energy Status for Remote Sensing Satellites

The invention discloses an onboard energy scheduling method based on energy states and applicable to remote sensing satellites. The method comprises steps that power supply state intervals are divided according to charge conditions of a storage cell set, onboard computer resources are utilized to acquire relevant parameters of an energy system in real time, for an injected satellite work mode, an energy system power supply state is calculated, and scheduling is carried out to determined whether the work mode can be performed. According to the method, power supply capacity and a load electricity load state of the onboard energy system are determined according to the remote measurement parameters in real time, calculation deviation caused by inaccurately-acquired ground budget parameters can be avoided, autonomous onboard energy state calculation under a multi-combination variable work mode is realized, an onboard energy utilization rate is substantially improved, and satellite business capability is improved; according to the autonomous onboard energy state calculation result, onboard energy scheduling can be timely carried out, excessive energy utilization under energy system fault and electricity load increase conditions can be avoided, and safety of the onboard energy system is improved.
Owner:BEIJING INST OF SPACECRAFT SYST ENG

News subject popularity calculation and sorting method and device, equipment and storage medium

The invention belongs to the technical field of data processing, and particularly relates to a news subject popularity calculation and sorting method and device, equipment and a storage medium. The method comprises the following steps: acquiring a main body set E, and calculating a basic news popularity ratio of any main body c in a current calculation period t; calculating a historical average news popularity ratio of each subject; after the subjects with the basic news popularity ratio larger than the historical average news popularity ratio are sorted in a preset sorting mode, taking the first N subjects; calculating basic transaction values for the first N main bodies respectively, and obtaining the transaction values after normalization processing is carried out on the basic transaction values; and performing descending sorting according to the transaction values, and outputting a sorting result. According to the method, the popularity and the popularity change rate of the subjects are considered, the subjects with high news popularity are prevented from being ranked in the front all the time, and the subjects with large news popularity change rate and extremely low news popularity value are also prevented from being ranked in the front.
Owner:数库(上海)科技有限公司

A Boundary Setting Method for Turbulent Kinetic Energy Entrance of Flow Around a Hypersonic Blunt Front

The invention discloses a method for setting the turbulent kinetic energy inlet boundary of a hypersonic obtuse leading edge flow, which includes the following steps: S1, calculating the basic flow field, and obtaining the steady basic flow field variable; S2, using a numerical simulation system to directly simulate the disturbance wave, Get unsteady flow field variables ϕ ; S3, analyze the flow field to get the disturbance field ϕ' , and obtain the distribution characteristics of the turbulent kinetic energy; S4, set the inlet boundary of the turbulent kinetic energy; S5, calculate the turbulent flow / transition, etc.; the present invention does not need to modify the turbulent kinetic energy equation in the turbulent flow model, and the turbulent kinetic energy can be avoided by setting the inlet boundary condition The calculation deviation of the equation in the downstream of the shock wave is based on the direct numerical simulation results to set a more accurate turbulent kinetic energy inlet boundary condition, which has the advantages of reasonable calculation results, high achievability, and high reliability, and can be extended to three-dimensional flow conditions, etc.
Owner:CALCULATION AERODYNAMICS INST CHINA AERODYNAMICS RES & DEV CENT

Insulation detection method and device for electric vehicle

The invention discloses an insulation detection method and device for an electric vehicle. The method comprises the steps that a first voltage parameter of a vehicle-mounted rechargeable energy storage system to an electric platform is collected; after a first resistor is connected between the vehicle-mounted rechargeable energy storage system and the point platform, a second voltage parameter of the vehicle-mounted rechargeable energy storage system to the point platform is collected; after the first resistor is disconnected, acquiring a third voltage parameter of the vehicle-mounted rechargeable energy storage system to the electric platform; according to the first voltage parameter, the second voltage parameter, the third voltage parameter and the first resistance, calculating an insulation resistance parameter of the vehicle-mounted rechargeable energy storage system to the electric platform; the third time of sampling is carried out after the first resistor is disconnected, and the insulation resistance parameter of the vehicle-mounted rechargeable energy storage system to the electric platform is calculated based on the voltage parameters sampled for three times, so that calculation deviation caused by insulation or voltage jump and insulation resistance jump in the detection process can be prevented, and the accuracy of insulation resistance measurement of the electric vehicle is improved.
Owner:华人运通(山东)科技有限公司

Method for evaluating low-speed impact damage residual strength of winding composite material structure

The invention relates to a method for evaluating low-speed impact damage residual strength of a winding composite material structure. Comprising the steps of 1, low-speed impact damage simulation calculation of the winding composite material structure; step 2, outputting and importing a unit damage state; a predefined field variable analysis method is adopted to achieve transmission of damage information between low-speed impact damage and residual strength simulation of the composite material structure; 3, establishing a low-speed impact damage residual strength model of the winding composite material structure containing the initial damage; step 4, calculating residual intensity; the winding composite material structure low-speed impact damage residual strength model established in the third step is obtained; the method can meet the requirement for predicting the residual strength of an existing winding composite material structure after low-speed impact damage, finite element simulation is applied to low-speed impact damage residual strength calculation of the winding composite material structure, and the damage state, obtained through low-speed impact simulation calculation, of a unit is imported into a finite element analysis model; therefore, the transmission of damage information is realized.
Owner:CHANGZHOU INST OF TECH

A method for dynamically estimating noise from radar echoes and a weather radar system

The invention discloses a method for dynamically estimating noise through radar echo and a meteorological radar system and solves a technical problem of non-high meteorological prediction accuracy existing in a meteorological radar system in the prior art which can not acquire dynamically-changed system noise in real time. The method comprises steps that a radar echo signal is converted into an IQ sequence signal, Fourier transform of the IQ sequence signal with the sampling number of N in a kth distance database is carried out, a power spectrum coefficient is calculated to acquire power spectrums sp, the k is a positive integer; the power spectrums sp are ordered in an ascending order, and the ordered power spectrums sp are marked as S; variables mc and b0 are set, during initiation, the mc is made to be equal to the N, and the b0 is made to be 0; when it is determined that the mc is greater than 2, and the b0 is smaller than 1, cycle calculation is carried out according to formulas described in the specification; after each cycle calculation, whether the b1 is not greater than 0 is determined, and the present mc is recorded; if the b1 is not greater than 0, the system noise is estimated by employing the present mc, and thereby the system noise of the kth distance database is acquired according to a formula described in the specification.
Owner:BEIJING METABTAR RADAR

Online monitoring method for hour-level carbon emission of thermal power plant

The invention discloses a thermal power plant hour-level carbon emission on-line monitoring method, which comprises the following steps: forming a unit output-carbon emission intensity characteristic curve by using historical data learning based on a generating capacity method, and calculating the carbon emission according to the real-time output of a unit; calculating to obtain power generation carbon emission intensity by using the material consumption of the previous day based on a material method, and then calculating the carbon emission according to the real-time output of a unit; and calculating the carbon emission by using the carbon dioxide concentration or the oxygen concentration in the CEMS system based on a flue gas method. And determining the final unit hour-level carbon emission according to whether the carbon emission curves calculated by the three methods are in the same group or not. According to the method, hour-level accurate online monitoring of the carbon emission of the thermal power plant can be realized, the defects of a single calculation method are overcome, calculation result deviation caused by errors of a certain calculation method is avoided, and support is provided for accurate monitoring of the hour-level carbon emission of the thermal power plant.
Owner:TECH INNOVATION CENT OF CHINA HUANENG GROUP +3

An electrochemical gas sensor for joint detection of exhaled nitric oxide and exhaled hydrogen sulfide

The invention discloses a four-electrode electrochemical gas sensor capable of measuring both nitric oxide and hydrogen sulfide in expiratory air. A four-electrode system is formed by two working electrodes, one auxiliary electrode, one reference electrode, one hydrogen sulfide filter and an electrolyte. The four-electrode electrochemical gas sensor is characterized in that the two working electrodes are located on the same horizontal plane and are further spatially relatively independent; the two working electrodes are made from the same electrode material; the hydrogen sulfide filter is located above one of the two working electrodes. The shapes of the working electrodes are semicircular; the electrode material is a gold-doped carbon nanotube, graphite or graphene. The gold-doped workingelectrodes are sensitive to the hydrogen sulfide, and can be used for obtaining a hybrid response signal of the nitric oxide and the hydrogen sulfide; however, a response signal of the nitric oxide can be only obtained on the working electrode provided with the hydrogen sulfide filter; in this way, through calculating a difference value, response signals of the nitric oxide and the hydrogen sulfide can be both obtained on the sensor, and the sensor can be used for realizing simultaneously detecting expiratory nitric oxide and expiratory hydrogen sulfide.
Owner:SUNVOU MEDICAL ELECTRONICS

Considering the power grid stability calculation data construction method below 220kv

The invention discloses a power grid stability calculation data construction method considering power supplies below 220kV. The method comprises the following steps that 1. statistics is performed on regional power grid negative load total active power (which is expressed in the specification); 2. statistics is performed on regional power grid grid-connected set total active power output (which is expressed in the specification); 3. percentage K of networking load of the i region is calculated; 4. regional power grid stability calculation data of which K is less than or equal to 16% are constructed; 5. regional power grid stability calculation data of which K is greater than 16% are constructed; and 6, partial stability calculation data in the power grid of the regions of which K is greater than 16% are constructed again. Percentage K of the networking load of each region is calculated to distinguish the detail level of power grid stability calculation data construction of each region of the power grid so that the power grid stability calculation data meeting the actual situation further are constructed and the dynamic characteristics of the grid-connected power supplies of the power grid below 220kV of the system after transient disturbance can be better described.
Owner:STATE GRID CORP OF CHINA +2

Bidirectional automatic synchronous tension dimension inspection process

The invention discloses bidirectional automatic synchronous tension dimension inspection equipment which comprises a working table plate, wherein a concave groove is formed in the surface of the upper end of the working table plate, a bidirectional threaded rod is rotationally connected into the concave groove through a bearing, a T-shaped threaded block is in threaded connection with the outer surface of the bidirectional threaded rod, a lap joint plate is fixedly connected to the upper end surface of the T-shaped threaded block, a U-shaped plate is fixedly connected to the upper end surface of the lap joint plate, and a hydraulic cylinder is fixedly mounted at the upper end of the U-shaped plate. Through employing a servo motor, the bidirectional threaded rod, the T-shaped threaded block and three gear discs, the whole equipment can realize a bidirectional automatic synchronization function when tension dimension inspection is carried out, so that certain automation is achieved, through arrangement of a fixing frame, a camera and a sliding sleeve, the whole equipment can be known through image analysis during reading, the overall reading is more accurate, and later calculation deviation caused by errors is avoided.
Owner:昆山联友昌电子有限公司

An Error Correction Algorithm for Recursive Calculation of Relay Protection Device

The invention discloses an error correction algorithm for recursive calculation of a relay protection device. The error correction algorithm is used for realizing recursive calculation of signal processing to A / D sampling data of voltage and current signals accessing the relay protection device and also comprises the following steps: carrying out one-time non-recursive calculation on every adjacent recursive calculation data windows, comparing a non-recursive calculation result with a recursive calculation result, if the results are the same, continuing to carry out next-time recursive calculation, if not, replacing the recursive calculation result with the non-recursive calculation result, and then carrying out next-time recursive calculation. The error correction algorithm disclosed by the invention has the advantages that not only can the high efficiency of recursive algorithm be achieved, but also the security of non-recursive algorithm is obtained, the memory effect of the recursive algorithm is eliminated, unrecoverable calculation deviation caused by accidental errors is prevented and the security and the reliability for relay protection are improved.
Owner:NR ELECTRIC CO LTD +1
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