1725results about How to "Calculation method is simple" patented technology

The invention discloses a method for reconstructing a digital rock core and pore network model based on a random fractal theory. The method comprises the following steps of based on the multiple fractal features of a porous medium, performing fractal representing on a capillary pressure curve obtained by the conventional mercury intrusion method, inferring fractal expressions of random distribution density function, average value and variance by a random distribution theory, and combining the random theory and the multiple fractal theory to construct a digital rock core, so as to rapidly construct a three-dimensional micro-network model. The method has the advantages that the cost is low and is reduced; the capillary pressure curve is measured by the mercury intrusion method, the full-section rock core is used in experiment, and a micro-pore structure is fully displayed. According to the method, the computing method is simple and convenient, and the advanced method is adopted; the micro-pore structure of reservoir rock is complicated and irregular, and an extremely complicated system cannot be accurately described by the traditional classical theory, so after the method combines the multiple fractal theory and the random distribution theory, the micro-pore structure can be accurately represented, and the method is easily implemented by programming.

The invention relates to a brain vascular blood circulation dynamic analysis method and the apparatus thereof. According to the cerebral circulation vascular bed anatomical model, an equivalent network model which comprises 12 pipeline units simulating the brain circulation blood dynamics is built, and the relevant parameter calculation formulas are confirmed, by utilizing the formulas, the flow rate waveform and the value inside the cartid artery, the pressure waveform, the blood pressure of the body, the diameter of the blood vessel, the flow rate waveform and the valve of the vertebral artery and the front, the middle and the rear parts on two sides inside the skull, and the characteristic and the parameter of the cartid artery and each blood vessel section inside the skull can be determined, the apparatus designed by the invention can be performed, the detecting system comprises the vessel diameter detecting of the cartid artery outside the skull, the blood pressure detecting, theblood flow rate detecting of the cartid artery outside the skull, the pressure waveform detecting of the cartid artery outside the skull, and the blood flow rate detecting on the artery inside the skull; the control system comprises a control module and a power supply module; the calculation and analysis system comprises a host computer, a peripheral equipment, and an analog-digital converter, the invention can fully analyze the brain circulation dynamic characteristic, thereby having notable effect on the early stage and the ultra early stage diagnosis and therapy of the brain vascular illness.

The invention discloses an attitude control method. The attitude control method comprises the following procedures that the on-satellite time influencing the satellite attitude precision is aligned through a second pulse signal; a satellite sensor error used for satellite attitude measurement is corrected in real time; the gravity gradient disturbance torque of an oblique flying satellite is compensated through a dynamics coupling relationship; the satellite flexibility is restrained through an input forming control method in the attitude controlling process; the attitude control law of an angular velocity feedforward instruction is increased through position and speed double loops and a position correcting loop to achieve high-precision and high-stability attitude guidance control; and quick attitude maneuver of the large-inertia satellite is achieved through a saturated sliding mold structural control algorithm. The attitude control method has the advantages that the computing method is simple, control is flexible, the attitude control method can be applied to attitude control of the large-inertia large-flexible oblique flying satellite, the property of the satellite is greatly improved, and researching and manufacturing cost of satellite hardware is reduced.

The invention relates to a crop evapotranspiration model-based intelligent drop irrigation control system and a method thereof. The drop irrigation system is arranged in a greenhouse and is characterized by comprising a data acquisition module, multiple A/D conversion modules connected with the data acquisition module, a controller (3), a D/A conversion module, a driving circuit and an execution mechanism, wherein the data acquisition module is used for acquiring a corresponding input signal, the signal output terminal of the data acquisition module is connected with the signal input terminal of a corresponding A/D conversion module, the signal output terminal of the A/D conversion module is connected with the signal input terminal of the controller (3), the controller (3) controls an output driving circuit connected with the controller, and the execution mechanism is operated by virtue of the driving circuit to realize irrigation. In the invention, the evapotranspiration is calculated and is indirectly taken as irrigation volume to carry out irrigation on a crop, and moisture required by the crop is supplemented more accurately; and the structure is simple, and the cost is low, thus the system and the method provided by the invention have high promotional value.

The invention discloses a data assimilation method for monitoring soil moisture. The method provided by the invention at least comprises an assimilation cycle, and each assimilation cycle comprises the following steps: (1) an ecological process model serves as a dynamic model to stimulate the space distribution state of soil moisture every day, the initial value in the dynamic model is an initial parameter and an initial soil moisture data, and the dynamic model is operated to output simulative soil moisture data; remotely sensed data on the soil surface is performed with inversion to obtain surface layer soil moisture data; the simulative soil moisture data in the remotely sensed data corresponding date is combined with the surface layer soil moisture data obtained by remotely sensed data inversion for data assimilation so as to obtain an optimized ecological process model parameter; (2) the optimized parameter is substituted into the dynamic model in step (1) to operate the dynamic model so as to obtain simulative soil moisture data every day. The method provided by the invention can connect soil moisture variety with vegetable physiological response mechanism by water deficit and stress, which improves the precision of field soil moisture monitoring and drought evaluation and has important application prospect.

An input apparatus includes an input unit via which a user can point specific coordinates on a screen, and a display unit for displaying a graphical user interface (GUI). A menu for selecting an arbitrary item from a plurality of items is displayed on the GUI. When the user conducts manipulation to move a location of coordinates pointed by the user on the screen so as to draw a circle, center coordinates of a circle locus of the manipulation are presumed regardless of the location of the coordinates. An item selected in the menu is moved so as to be associated with a rotation angle of the manipulation with respect to the center coordinates. The user can conduct selection manipulation of consecutive menu items without depending upon the location of coordinates pointed by the user on the screen.

The invention provides a touch screen data processing method for inhibiting noise and a touch screen control device which applies the method. The method comprises the following steps: (1) receiving an analog signal of a touch screen, and sampling the analog signal of the touch screen to obtain a digital signal; (2) according to a sampling value, calculating a reference value corresponding to the sampling point; (3) comparing the sampling value and the corresponding reference value to obtain a deviation, and comparing the deviation with a preset threshold value; (4) if the deviation is smaller than the threshold value, keeping the sampling value, abandoning the sampling value if the deviation is greater than the threshold value, and replacing the sampling value with the corresponding reference value obtained by the calculation; and (5) applying the data obtained in the step (4) to touch information processing, and calculating a touch position. The method can effectively inhibit common-mode noise and improve the detection precision of a touch position. Compared with a traditional noise elimination method, the touch screen data processing method has the following outstanding advantages of being simple in calculation method, small in hardware resource occupation when a touch signal is realized and high in processing speed, is not affected by the length of a scanning signal and can calculate the signals of any length.

The invention discloses a PMSM rotary transformer zero position initial angle calibration method and calibration system. The PMSM rotary transformer zero position initial angle calibration method comprises steps of connecting an PMSM, on which a rotary transformer is installed, to a driving motor, enabling a motor stator of the PMSM to perform three-phase short circuit, using the driving motor to drive the PMSM to rotate forward and maintain at a preset rotation speed, using an electronic control unit to perform sampling on three phase current Ia, Ib and I c and a rotary transformer reading phi read at a same moment, using the rotary transformer reading phi read to perform Park conversion on three phase current Ia, Ib and Ic to obtain current vectors Is,p, calculating a vector angle theta p corresponding the current vector Is,p, using the driving motor to drive the PMSM to rotate backwards and maintaining the rotation at a preset rotation speed, using the electronic control unit to record a vector angle theta n corresponding to a current vector Is,n when the motor is rotated backwards, and calculating that a practical electric rotation angle theta 0 corresponding to the rotary transformer reading zero point angle is a zero position initial angle according to a formula theta 0=(thetap+thetan)/2-180 degree.

The invention provides a test device used for testing a three-dimensional strained condition. The device structurally comprises 12 strain gauges, wherein an arrangement mode of the 12 strain gauges is that two strain gauges are put into one group, the 12 strain gauges are respectively stuck on six edges of a regular tetrahedron, and the six edges are hinged to form a regular tetrahedron skeleton OABC. Meanwhile, the invention also provides a test method used for testing the three-dimensional strained condition. The test device used for testing the three-dimensional strained condition and the test method used for testing the three-dimensional strained condition provided by the invention have the effects that the device and the test method have the advantages of low price, simple computation method, reasonable construction and convenience in operation. A direct and effective means is provided for better understanding the strained condition and stress condition in a stressed body. A three-dimensional strained rosette is arranged in a material to be tested, and 12 strain values on six edges of the three-dimensional strained rosette are read. According to the measured strain values and a spatial position relationship between the three-dimensional strained rosette and the material to be tested, the magnitude and the direction of the main stress, the maximum shearing strain, the volumetric strain and the generalized shear strain of the object to be tested are calculated according to requirements. The invention fills up a blank in the measurement of the three-dimensional strained condition of an object.

The invention provides alternating-current phasor analysis method and small signal model modeling method suitable for dual-active bridge (dual active H bridges, dual three-level half bridges or a three-level half bridge on one side and an active H bridge on the other side and the like) direct-current converters in all phase-shifting controls. The alternating-current phasor analysis method and small signal model modeling method comprise the specific steps as follows: (1) an alternating current side of each active bridge is equivalent to two square-wave voltage sources through equivalence, and square-wave voltage is decomposed into superposition of sinusoidal voltage through Fourier series decomposition to obtain phasor expressions, as shown in the specification, of (2n+1)th component voltage and inductive current; (2) phasor diagrams of control characteristics and control ranges under different phase-shifting controls are obtained according to the phasor expressions in the step 1; (3) complex power, as shown in the specification, of the (2n+1)th component is obtained according to the phasor expressions in the step 1, and active and reactive power characteristics of the dual-active bridge direct-current converters under different phase-shifting controls are analyzed; and (4) time domain Fourier series and expressions of the voltage and the current are obtained according to the phasor expressions in the step 1, so as to obtain a unified signal model suitable for all phase-shifting control methods.

The invention discloses a spaceborne dual-channel angle tracking calibration system and a method. The system comprises an antenna device, a polarization duplexer, a synthesis network, a sum-path receiver, a difference-path receiver, a transmitter, a digital signal processor and a calibration device. Due to the calibration device, the system can realize real-time compensation for an angle error signal within each period, thereby improving the system precision; and meanwhile, the calibration device of the invention has the advantages of simplicity and easy implementation.

The invention relates to a fast calibration method of a single-phase electric energy meter. According to the fast calibration method, the gain initial value of a power gain correction register of a metering chip of a calibrated meter is preset so as to be fast positioned to a target error value, only a 100%Ib-point 0.5-induction error point is debugged; apparent power deviation and active power deviation are simultaneously obtained at the error point; 100%Ib-point 1.0-resistance gain correction is performed through utilizing the apparent power deviation; 100%Ib-point 0.5-induction phase correction is performed through utilizing the active power deviation; and a 100%Ib-point 0.5-induction error value which has been obtained through calculation is directly utilized to perform 5%Ib-point 1.0-resistance small signal correction, and therefore, too long debugging time of small signals can be avoided. The fast calibration method has the advantages of fast error target value positioning, high meter calibration efficiency and significantly-improved accuracy.

The invention provides a high-strength bolt strength calculating method of a wind generating set. The high-strength bolt strength calculating method provided by the invention comprises the following steps of: combining a VDI (Virtual Device Interface) 2230 standard and finite element analysis; modeling by using the finite element analysis; setting boundary conditions and obtaining stress increment of a bolt under the external loading effect by solving; and obtaining ultimate strength of the bolt after considering factors in two aspects of influence on the stress by a bolt pre-fastening force supplying manner through the VDI 2230 standard. A screw part is simulated by using a three-dimensional beam unit in a modeling process; and the stress condition is simulated by that a bolt thread part is engaged with a screw hole, and a bolt head and the screw part can be limited by multiple joints. The high-strength bolt strength calculating method is used for reasonably simulating the bolt by more completely considering a comprehensive stress condition of the bolt, can be widely applied to all high-strength bolt strength checks except a tower cylinder connection bolt in the wind generating set, and provides reliable proof for the design of the high-strength bolt.

The invention relates to a method for measuring a liquid phase diffusion coefficient, and an apparatus thereof, and belongs to a method for measuring a diffusion coefficient of a liquid by adopting yellow light LED as a light source based on a capillary imaging method. According to the present invention, a transparent capillary is adopted to construct a liquid phase diffusion cell; the specific refractive index spatial resolution measurement capability of the capillary imaging method is adopted to directly observe and record the diffusion regularity of the thin layers of the diffusion medium in the capability, wherein the thin layers of the diffusion medium have the same refractive index; the liquid phase diffusion coefficient is calculated based on the Fick second law. With the present invention, the diffusion coefficient between glycerol and purified water is measured at a room temperature of 25 DEG C, with comparing the diffusion coefficient 0.720*10<-5> cm<2>/s reported by the literature of the traditional holographic interferometry method with the diffusion coefficient 0.715*10<-5> cm<2>/s measured by the method of the present invention, the relative error is 0.69%; the capillary is adopted to construct the liquid phase diffusion cell, such that the amount of the required sample is less, the measurement speed is rapid, the anti-interference capability is strong and the system stability is good.

The invention relates to a correction method for an incomplete or deformed quadrangular image. The method comprises the five steps of edge point detection, abnormal edge point elimination, linear fitting, vertex calculation and image correction. The correction method for the incomplete or deformed quadrangular image is applied to an identification method identification system for certificates such as valuable documents, notes, identification cards and the like, and can be used for rapidly performing edge detection and tilt correction on defect and deformed valuable documents, notes or certificate images.

The invention discloses a double-feed wind power generator stator short circuit current calculating method under the condition of asymmetric faults. The method comprises the following steps: establishing a voltage equation and a flux linkage equation of a double-feed wind power generator, in the form of space vectors under a stator shaft system; establishing stator and rotor current expressions, and establishing a stator positive sequence flux linkage expression after the faults; establishing a rotor positive sequence flux linkage expression after the faults; establishing a stator positive sequence current expression of the double-feed wind power generator under the condition of an asymmetric fall of voltage at a machine end; establishing a stator negative sequence flux linkage expression after the asymmetric fall of the voltage at the machine end; establishing a rotor negative sequence flux linkage expression after the asymmetric fall of the voltage at the machine end; establishing a stator negative sequence current expression after the asymmetric fall of the voltage at the machine end; and finally obtaining a stator current expression after the asymmetric fall of the voltage at the machine end. According to the invention, the problems of affected relay protection and control accessed to a wind power field, affected safe and stable operation of a wind power generator set and the like, caused by lack of research on a simple and effective stator short-circuit current calculation method under the condition of the asymmetric faults in the prior art are solved.

The invention discloses a negative-damping low-frequency oscillation and forced power oscillation distinguishing method, relating to scheduling automation of a power system and safety operation of a power grid. The method comprises the following steps of: calculating energy flow direction factors of all generators and load branches based on data acquired by a power grid wide area measuring system (WAMS) when negative-damping low-frequency oscillation or forced power oscillation happens in the power grid; judging whether a definite external disturbance source exists in the power grid; if the definite external disturbance source exists, judging that a low-frequency oscillation mechanism is based on forced power oscillation; and if no external disturbance source exists, judging that the low-frequency oscillation mechanism is based on negative-damping low-frequency oscillation. The negative-damping low-frequency oscillation and forced power oscillation distinguishing method has the advantages that the basis is provided for the power dispatching department to take corresponding measures for rapidly inhibiting oscillation when the power grid has low-frequency oscillation; in addition, the calculating method is simple and feasible, high in calculating speed, capable of meeting the requirement of a real-time oscillation judgment mechanism of the power grid and strong in practicability.

The invention discloses a hard roof mine impact ground pressure hazard risk prediction analysis method. The hard roof mine impact ground pressure hazard risk prediction analysis method comprises substituting obtained mechanical parameters into an energy release equation based on an occurred impact ground pressure hazard to obtain the energy increase degree REC; performing the quantitative characterization on the energy absorption degree AEC according to six divided supporting schemes; dividing specific mine impact ground pressure hazard risk prediction analysis frameworks according to the degree of the influence on mining, wherein the formula of the impact ground pressure hazard potential RDP is as follow; calculating the impact ground pressure hazard potential produced in the mining process of the high press area in the process of the newly occurred hard roof breaking and performing comparison on the impact ground pressure hazard potential and the established impact ground pressure hazard risk prediction analysis frameworks to determine the hazard degree of the impact ground pressure. According to the hard roof mine impact ground pressure hazard risk prediction analysis method, the scientific quantification is performed on the impact ground pressure hazard potential induced by the hard roof breaking in a mine, the calculation method is simple, the required mechanical parameters are easy to obtain, and the impact ground pressure hazard risk of the hard roof mine is simply and conveniently determined.

The invention discloses a method for analyzing the depth of the crack of a thin plate based on ultrasonic lamb waves and a time-reversal theory. The method comprises the following steps: selecting a thin plate with a crack, and stimulating single-mode Lamb waves IA(t) in the excitation point A of the thin plate; carrying out a sectioning technology to obtain a multi-mode domain signal received by a reception point B, carrying out the time-reversal technology to obtain a reconstructed signal I'A(t) at the point A, and calculating the waveform damage index DI of the reconstructed signal I'A(t) and an excitation signal IA(t); selecting thin plates having different crack depths L, repeating above steps to obtain corresponding waveform damage indexes DI, and carrying out data fitting through a least square technology to obtain a relation between the crack depth L and the waveform damage index DI; and detecting a thin plate with the crack having an unknown depth to obtain the DI value in order to determine the crack depth L. The sectional calculation technology is adopted to effectively solve the problem of propagation of the Lamb waves in a sheet having defects; and the r time-reversal theory is adopted to reconstruct the signal waveform in order to solve the multi-mode problem and the unable identification problem of the reception point, caused by long distance transmission.

The invention discloses a device and a method for measuring the chirp parameter frequency response characteristics of an electro-optic intensity modulator, and relates to the technical fields of electronics. The device comprises a tunable laser, a polarization controller, a modulator for electro-optic intensity to be measured, a microwave signal source, a first optical connector, a second optical connector, a single mold optical fiber, an optical power meter, a photoelectric detector, a microwave power meter, a data collecting card and a computer, wherein the tunable laser, the polarization controller, the modulator for electro-optic intensity to be measured, the first optical connector, a dispersion optical fiber group, the second optical connector and the photoelectric detector are sequentially connected through optical paths, and the photoelectric detector, the microwave power meter, the data collecting card, the computer and the microwave signal source are sequentially connected through circuits. The device and the method have the advantages that the measurement precision is high, and the operation is convenient. The device and the method have important application prospects in aspects of optical fiber communication systems, electro-optic intensity modulator analysis and optical signal processing.

The invention discloses a method for controlling an anti-lock braking system of automobiles, which bases on least squares support vector machines (LS-SVM) and relates to the technical filed of the electronic control of the automobiles. The controlling method estimates automobile body deceleration according to the wheel velocity peak values of four wheels; the automobile body reference speed is calculated according to the automobile body deceleration and then the reference slip rate of the wheels is obtained by calculation; the angular deceleration of the wheels is calculated according to the angular speed of the wheels; the angular speed and reference slip rate of every wheel are respectively taken as input to construct a controller of the least squares support vector machines; the expected brake pressure of every wheel is calculated; according to the expected brake pressure, a pulse width modulation method is adopted to control the on/off time of an electromagnetic valve, thus controlling the brake pressure and realizing safety braking. The method is applicable to controlling the anti-lock braking system (ABS) of automobiles.