66 results about "Two point method" patented technology

The invention discloses a fixed-point method for a floating-point operation. The method comprises the steps that according to a preset numerical range and the calculation precision requirement, the exponents and significant bits of adjustable-precision floating-point data are adjusted, and the parameter data in a single-precision floating-point format are converted into adjustable-precision floating-point data; when calculating is carried out, the adjustable-precision floating-point data are converted into fixed-point data and used for calculation, and an intermediate result generated by calculation is converted into adjustable-precision floating-point data; a final result is generated after all calculation; and the final result is converted to data in the single-precision floating-point format. According to the invention, standard floating-point data can be represented with a 16-bit bit width or a smaller bit width to realize fixed-point conversion of the floating-point operation; the storage space is saved; the operation performance is improved; and the calculation precision is not influenced.

In a mobile device for moving a mobile body in mutually orthogonal two- or three-axis directions, a positional error of the mobile body with respect to a direction orthogonal to preset two-axis directions out of the above two- or three-axis directions is used to determine, by using a sequential two-point method, a straightness error curve representing a change status along one-axis direction out of the above two-axis directions; the straightness error curve determining is repeated for the other one-axis direction out of the above two-axis directions.

The invention discloses an online measurement system and a method for plane shape errors. The system comprises a sensor array, a data collection and analog-to-digital conversion module and a data processing and displaying module, wherein a modified least square successive two-point method plane shape error separation algorithm is used in processing software of the data processing and displaying module, and a data combining and fitting technique is introduced. The method is based on the modified least square successive two-point method plane shape error separation algorithm. The whole sampling data of a plane to be measured are subjected to partitioned processing, dimensionality reduction processing of the data array is achieved through an online partitioning algorithm, then the data processing speed is improved, the capacity of sampling points is increased, and the method mainly comprises processes such as data error separation and fitting. The data combining and fitting technique is used, so that the distribution density of sampling points is improved effectively, and the capability that a measurement system reflects the plane shape error of the plane to be measured is improved.

This invention relates to a method of detecting N-acetyl-beta-D-aminoglucosaccharase, and its stable solution. It characters: use its stable solution to automatically carry the detection of N-acetyl-beta-D-aminoglucosaccharase in human fluid by the fixing time two point method and detecting method continuously.

The invention relates to a voltage stability analyzing method and device, and in particular relates to a voltage stability analyzing method and device based on short circuit capacity. The main operating method comprises the following steps of: A, deriving the relation between the load busbar voltage and short circuit capacity by an analytic method according to a load node Thevenin's equivalent circuit; B, based on the relation between the load busbar voltage and short circuit capacity, deriving the minimum short circuit capacity keeping the load busbar voltage stable; C, solving the short circuit capacity provided by a system side by a two point method; and D, establishing a busbar voltage stability margin measuring index and a voltage safety criterion. Based on the load busbar short circuit capacity and by analyzing the voltage stability problem on the load side and the system side, the invention provides a new electric system voltage stability analyzing method which overcomes the defects of the continuation power flow full-grid load increasing mode, solves the problem of evaluating the voltage stability on the system side or the load side singly, and has good application value and popularization prospect.

The invention relates to a robust state estimation method based on an interior point method for an electrical power system, which belongs to the technical field of electrical power system operation and control. The method comprises the following steps: obtaining measurement data, performing topology analysis, and calculating power grid parameters; establishing an exponential function robust state estimation model; introducing a residual variable, and performing an equivalent transformation on the robust state estimation model, so as to specify the robust state estimation model to be in a form which is easy to solve by the interior point method; and solving the state estimation model after the equivalent transformation by virtue of the interior point method, and performing numerical approximation on a Hessian matrix. According to the method disclosed by the invention, due to the equivalent transformation for the state estimation model, the difficulty of robust state estimation for the electric power system is reduced; due to approximation for the Hessian matrix, the calculation efficiency of the robust state estimation for the electric power system is greatly increased; a state estimation result strictly meets a zero-injection equality constraint; and the calculation method is great in robustness.

The invention relates to an improved three-point method for turning error and roundness error measurement. The method includes the following steps that: three displacement sensors are distributed at different angular positions so as to measure the radial run-out of a detection bar, and a high-frequency data acquisition system is utilized to record the measurement results of the sensors, and a three-point error separation technology is utilized to calculate the Fourier coefficients of harmonic waves of roundness error; the second sensor and/or third sensor is re-installed at different angles, the three-point method is repeated to perform measurement for many times, so that each Fourier coefficient can obtain a plurality of estimated values; a Fourier coefficient which is calculated through a transfer matrix of which the determinant is maximum is a most accurate Fourier coefficient estimated value; and the roundness error can be calculated through composite calculation based on the most accurate Fourier coefficient estimated value. With the method of the invention adopted, the accuracy of the estimation of each harmonic wave can be improved, and therefore, the accuracy of whole roundness error measurement can be improved.

The invention provides a method for identifying stator resistance parameters, comprising the following steps: adopting the two point method on the basis of the ordinary direct current (DC) voltammetry to set two winding current target values; and injecting DC at twice and respectively recording the voltage value and current value of the DC and obtaining the stator resistance value by differentiation and integration. The voltage drop of an insulated gate bipolar translator (IGBT) and the voltage drop of a freewheel diode are cancelled out in computation, so that the identification precision is improved, dependency on devices is eliminated and the adaptability is very good.

The invention provides an active distribution network voltage drop simulation and evaluation method. The method comprises the steps that 1, the existing distribution network analysis software is used to build a model, and network flow is calculated; 2, through two-point method sampling, distribution network fault data and distributed power supply capacity data are produced, and a simulation scheme is determined; 3, simulation calculation is carried out, and expectation, variance, a three order central moment, a probability density function f(xi) and an SARFIx index of each node voltage drop are calculated; 4, a Monte Carlo method is used to calculate a probability density function f(xi) MC and an SARFI'x index of each node voltage drop amplitude; 5, the f(xi) and the f(xi) MC are compared, and the SARFIx index and the SARFI'x index are compared; and 6, if a comparing requirement is not met, returning to the step of 2 is carried out. Compared with the existing technology, the active distribution network voltage drop simulation and evaluation method provided by the invention has the advantages that various short circuit faults in a power distribution network are comprehensively considered; the method can adapt to power distribution networks of various wiring modes; and the calculation efficiency is high.

The invention discloses a thermal infrared imager inhomogeneous correction coefficient generation and control method. The thermal infrared imager inhomogeneous correction coefficient generation and control method comprises that 1.infrared focal plane response data when infrared focal plane is respectively in high temperature and in low temperature are collected. 2. A gain factor G of a two point correction method is calculated through an upper computer and the gain factor G is downloaded into a parallel flash. 3. A startup loads gain factor G into a static random access memory (SRAM) from the flash. 4. A deviation ratio O is received through one time one point correction coefficient motion. 5. An offset compensation correction coefficient generation is controlled by analyzing a detector work temperature. 6. Steps are that two points plus one point inhomogeneous correction is proceed and correction results are output and the like. The thermal infrared imager inhomogeneous correction coefficient generation and control method removes calculation and storage process of the two-point method coefficient and reduces a half of the flash memory capacity. The load process and the download process of the inhomogeneous coefficient are shortened. The thermal infrared imager inhomogeneous correction coefficient generation and control method quicken a read-write speed of the flash by utilizing the flash design. The efficiency of the circuit is improved greatly.

The invention discloses a four-point transformation based image adaptive-correction method, which is easy to implement and transplant, simple in operation, convenient to use and high in correction precision. The image correction method disclosed by the invention is implemented through acquiring double vision images, taking one of the double vision images as an original image, respectively acquiring four points on the original image and extracting an original image point; connecting the four points so as to form an arbitrary quadrilateral; through a mapping relation, obtaining corresponding four points, an original image point and an arbitrary quadrilateral on the other image and corresponding and traversing the image through double mice, thereby realizing the correction of the image, wherein in the process of building the arbitrary quadrilateral, a situation that no blind point or blind area occurs in areas outside the arbitrary quadrilateral is ensured by using an external expansion two-time method or an indentation two-point method, thereby realizing the adaptive correction, so that the image is corrected efficiently and accurately. The method disclosed by the invention can be applied to the field of image correction.

The method for making accurate restructure of difference measurement by using time domain is characterized by that according to the difference value obtained by measuring two different separation distances or shearing quanties of measured object, respectively using successive two-point method to evaluate two groups of different difference values, the number of evaluation curves obtained by every group is the ratio value of correspondent sensor separation distance or shearing quantity and sampling interval, then utilizing the interrelationship between two groups of the curves to calculate the influence of zero modulation error to the evaluation result so as to resolve the interrelationship between every curves in the two groups of curves, finally synthesizing these curves into an evaluation curve.

The invention provides a method and device for controlling the temperature of an SCR reactor. The method for controlling the temperature of the SCR reactor includes the steps that an SCR dynamic temperature model is established according to the experimental measurement temperature before the SCR reactor and a two-point method with a delay first-order inertia link fitting function; a Smith predictor is used for conducting calculation to obtain a compensation value according to the characteristics of the SCR dynamic temperature model; the compensation value can eliminate a lag link in the SCR dynamic temperature model; a difference value obtained by subtracting the sum of output of the SCR dynamic temperature model and the compensation value from the preset temperature of the SCR reactor is calculated; a feedback signal containing the difference value is received, the rear fuel injection quantity of an engine is calculated according to the difference value, a signal containing the rear fuel injection quantity of the engine is sent to the engine, and the engine is controlled to conduct rear injection according to the rear fuel injection quantity so as to control the temperature of the SCR reactor. According to the method, the stability of control over the temperature of the SCR reactor is improved.

The invention provides a single-phase voltage sag detection method and system based on an EEMD (ensemble empirical mode decomposition) method and a two-point method and application. According to the method, a sampling value is utilized to construct a data segment suitable for online calculation, the EEMD method is utilized to extract network voltage fundamental waves, harmonic interference is filtered out, the sage depth and phase jump angle of a current network voltage are calculated through the two-point method, and finally voltage sag online rapid detection is realized. Therefore, an original signal can be decomposed into IMF with different frequencies, and most harmonic components can be filtered out; and in combination with the EEMD method, the problem that the two-point method is notapplicable under the situation that harmonic distortion is contained is solved, and the advantages of rapidity and accuracy of the two-point method are reserved.

The invention discloses a direct earth capacitance gauge in a converting station power distribution system. The direct earth capacitance gauge comprises a signal acquisition device, a master controller, and an H-bridge inverter circuit, wherein the signal acquisition device is used for acquiring current signals and voltage signals in an arc suppression coil, the master controller has control, analysis, and operation functions, and the H-bridge inverter circuit is used for supplying converting signals for an electric network. The signal acquisition device, the master controller, and the H-bridge inverter circuit are successively connected, wherein an input end of the signal acquisition device and an output of the H-bridge inverter circuit are connected with a grounding device of the electric network arc suppression coil. Compared with a traditional single-phase metal grounding method, the method of the direct earth capacitance gauge is free of manufacturing fault intentionally, avoids system risk, and aims at that the arc suppression coil has a running mode added with damping resistance close to resonance point and a running mode without being added with the damping resistance far from the resonance point at present, and then two different measuring ways, namely a two-point method and a variable-frequency method, are respectively designed. Can not only precision of direct earth capacitance of the system be guaranteed, but also the direct earth capacitance gauge cannot bring negative influence to the system.

A determination method of the 1-deoxynojirimycin content in silkworm powder relates to silkworm powder. The method comprises the following steps: weighing two 1-deoxynojirimycin control samples used as control liquid 1 and 2; sucking the control liquid 1 and 2, injecting the samples; weighing silkworm powder to be determined, adding petroleum ether, performing heating reflux and extraction in water bath, filtering, removing the filtrate, volatilizing the petroleum ether to dryness to obtain a product A; adding methanol in A, performing ultrasonic extraction, filtering, concentrating the filtrate, adding in a neutral alumina column, performing elution, collecting the eluted solution, evaporate to dryness, dissolving by methanol and obtaining a constant volume so as to used the solution as a test solution; performing HPLC analysis of the test solution, calculating the 1-deoxynojirimycin content in the silkworm powder to be determined by an external standard two-point method according to a peak area value. The method has the advantages of high precision, good repeatability and stability, qualified sample recovery rate, simplicity and practicality, and the like, can be popularized in general laboratories, and is applicable to the quality control of 1-deoxynojirimycin in silkworm powder products.

The invention relates to a super-precise measuring method based on scanning of multiple sensors. The super-precise measuring method includes the following steps that two sets of sensors with difference intervals are constructed, a successive two-point method is adopted by the two sets of sensors to reconstruct two sets of linearity contours, and the interval between the two sets of linearity contours is determined, so that same sampling points can be found in the front set of curves and the rear set of curves; if a certain curve in one set of curves and a certain curve in the other set of curves at least share two identical sampling points, relative displacement amount and inclination amount between the two curves are calculated according to the two identical sampling points, so that the position relation between the two curves is determined; as the mutual position relations between the first set of curves and a certain curve in the second set of curves in the first set of curves are respectively determined, the mutual position relation of the first set of curves is determined and therefore, linearity contours of a detected surface are accurately reconstructed on all the sampling points. The super-precise measuring method based on scanning of multiple sensors is high in measuring precision, high in measuring speed, and capable of eliminating errors of a sensor system and linearity errors of a scanning platform.

The present invention relates to a determination method for content of active ingredients in a traditional Chinese medicine extract, particularly to a determination method for content of saccharide components in a mongolian milkvetch root extract. The method comprises the following steps: 1) preparing a saccharide component control solution; 2) dissolving a mongolian milkvetch root extract, adding the dissolved mongolian milkvetch root extract to a small solid-phase extraction column, carrying out water elution, and collecting eluent; 3) adopting a high performance liquid chromatography method to carry out sample determination, wherein a PrevailTM Carbohydrate ES chromatographic column is adopted, and a certain proportion of an organic solvent and water are adopted as a mobile phase to carry out elution; 4) adopting an ELSD detector to carry out detection; and 5) adopting an external standard two-point method logarithmic equation to respectively calculate fructose content and sucrose content. The determination method has characteristics of simple operation, rapidness, strong specificity, high separation, good accuracy and good precision, and is suitable for quality control of the mongolian milkvetch root extract.

A process for manufacturing a crosslinkable hot-melt adhesive compound for coating and/or laminating surface formations is described, wherein a crosslinking constituent is micro-encapsulated by a silanized polybutadiene.

In a self-calibration method of an angle detector, an angle interval between first and second scale reader heads are set, so that a single rotation is not equally divided into an integer number of potions by a value of the angle interval and that a plurality of rotations N are equally divided into M equal portions by the value of the angle interval. Readings by the scale reader heads during N rotations of the divided circle are obtained at a pre-set data sampling interval. From differences in readings by these scale reader heads, data of the sequential two-point method relating to an angle scale error of the divided circle are obtained at the data sampling interval. The scale error of the divided circle at the data sampling interval is calculated by synthesizing the data using the fact that an average of the data for the rotations N reaches approximately zero.

The invention discloses a prediction function control method for coking heating furnace oxygen content. The prediction function control method comprises steps of modeling for an industrial process through the substantial data collected during the industrial process, dividing the model into a linear part and a non-linear part, using a counterpropagation nerve network to perform modeling on the non-linear portion, using a traditional linear two-point method to perform modeling on the linear part, using the prediction function control method to perform rolling optimization on the established model, and returning the feedback of correction so as to determine the control variable outputted at the next moment. The invention uses the prediction function, which, compared with the traditional PID control, can more effectively improve the dynamic performance and stability of the system.

The invention discloses a detection method of 1-deoxynojirimycin (DNJ) in a mulberry leaf extract. The detection method comprises the following steps: adopting a reversed-phase high-performance liquid chromatography-evaporative light scattering detection method, selecting an amino column to separate the 1-deoxynojirimycin in the mulberry leaf extract, adopting an evaporative light-scattering detector for matched detection and calculating the content of the 1-deoxynojirimycin by adopting an external standard two-point method. The detection method disclosed by the invention is simple and convenient to operate and good in precision degree, reproducibility and stability; pre-column derivatization and marking are not required to be performed on the 1-deoxynojirimycin before use; a detection instrument is moderate in price, good in popularization and high in sample recovery rate; the detection method is used for the detection on the content of the 1-deoxynojirimycin in the mulberry leaf extract, so that the effective method is provided for quality control on the mulberry leaf extract.

The invention discloses a device and a method for measuring wave dissipation characteristics of an arc-plate structure. The device is characterized by comprising an upper structure, the arc-plate structure, a lower structure, a wave height meter, a wave height data acquisition system and a wave water tank; the arc-plate structure is fixed from the lower portion through a specially-made stainless steel thin column, and the disturbance effect of a fixed support on water can be effectively weakened; a reflection coefficient of the arc-plate structure is calculated by adopting a Goda two-point method according to the wave height meter arranged in the wave water tank so as to analyze the wave dissipation characteristics of the arc-plate structure; the device for measuring the wave dissipation characteristics of the arc-plate structure is simple in structure and easy to operate, and the wave dissipation characteristics of the arc-plate structure can be comprehensively analyzed according to the calculated transmission and reflection coefficients.