18 results about "Linear term" patented technology

The invention discloses a Tokamak plasma magnetic response model construction method, a Tokamak plasma magnetic response model construction system and a medium. Relates to the technical field of nuclear fusion plasma simulation. According to the scheme, improvement is carried out on the basis of the prior art, modeling is carried out on the magnetic response of the Tokamak plasma on the basis of basic data of the Tokamak plasma, and plasma behaviors are directly learned from experimental data; the simulator taking the plasma magnetic configuration evolution autoregression model as a carrier can process nonlinear terms and high-order terms, and is low in calculation cost, high in speed and capable of being applied in real time; according to the method, the behavior of the plasma under magnetic control can be well simulated, the plasma behavior is directly learned from experimental data without simplifying and assuming plasma properties, and the method can be used for off-line simulation and can also be used for control strategy optimization or fault detection in real time.

The invention discloses a circular inductosyn error prediction method and system based on a hybrid model, and relates to the technical field of precision measurement, and the method comprises the steps: obtaining target position-error data; constructing a circular inductosyn error prediction model according to a normalization principle, a first harmonic linear term, a radial basis function neural network term, a dynamic parameter optimization mechanism and a linear superposition principle; and inputting the target position-error data into the circular inductosyn error prediction model to obtain an error prediction value. The problems of positioning misalignment, poor real-time performance and weak generalization ability of a high-precision servo system caused by temperature drift and complex interference are solved, efficient and reliable embedded real-time correction of the circular inductosyn is realized, and the error prediction precision of the circular inductosyn is improved.

The present application belongs to the field of gear design, and particularly relates to a design method of a drum-shaped modification curve of gear tooth direction, comprising: 1) constructing a whole C 2 smoothly continuous double circular-arc spline drum-shaped modification curve; 2) obtaining the coordinates of the common tangent point F i of the i-th double circular-arc segment of the double circular-arc spline drum-shaped modification curve; 3) constructing a multi-element nonlinear equation set; 4) obtaining an initial solution by solving the linear term of the equation set, and iteratively calculating the accurate solution of the multi-element nonlinear equation set; and 5) obtaining the drum-shaped modification curve of the gear tooth direction according to the accurate value of the intermediate variable chord tangent angle of the i-th double circular-arc segment. The drum-shaped modification curve of the gear tooth direction obtained by the present application adopts segmented low-order interpolation, can avoid the "Runge" effect of high-order interpolation, and has good properties of the first and second order derivatives of the drum-shaped curve. The curve has high fitting accuracy, is continuous and smooth, reduces the impact and vibration in the gear transmission process, improves the tooth surface contact state, and improves the gear transmission performance.

The invention relates to the technical field of rock stress analysis, in particular to a rock stress distribution analysis method, device and equipment and a medium. The method comprises the following steps: calculating a linear term required for solving a rock stress function according to principal stress applied to rock and a direction angle of the principal stress, mapping a pore boundary into a unit circle boundary on a complex plane based on conformal transformation, and performing Cauchy integration based on the unit circle boundary to obtain a nonlinear term required for solving the rock stress function. And obtaining an expression of a stress function based on the linear term and the nonlinear term, and finally calculating stress distribution generated in the rock according to the expression of the stress function. According to the method, the complex and irregular pore boundary is mapped into the regular unit circle boundary by adopting conformal transformation so as to reduce the calculation amount required for solving the stress function, and the pore boundary in any shape can be mapped into the unit circle boundary through conformal transformation, so that the calculation amount is reduced; therefore, the stress analysis method is suitable for stress analysis of rocks with pores in any shape.

The invention discloses an arbitrary-dimension simplest memristor Hamilton conservative chaotic system and a construction method and application thereof, and belongs to the technical field of information security. According to the system, a voltage difference type three-terminal memristor model is firstly built, then an n-dimensional Hamilton conservative chaotic system general formula is built, the memristor model is introduced into the n-dimensional Hamilton conservative chaotic system general formula, the simplest system is obtained through the steps of element replacement, parameter setting and the like, and multi-scroll expansion can be achieved by introducing a nonlinear function. A system mathematical model is simple, the proportion of nonlinear terms is low, hardware is constructed based on an ARTIX-7 FPGA platform, a 36Q32 format fixed-point number is adopted, resource consumption is low, data throughput is high, and output sequence randomness is high. The system can be applied to the fields of artificial intelligence data enhancement and random signal generation, provides a new path for high-dimensional conservative chaotic system modeling, and is suitable for information security application of resource-limited scenes.

The application discloses a SAR motion parameter estimation method based on accurate measurement of time of arrival and direction of arrival, which comprises the following steps: reading N LFM direction of arrival alpha n and corresponding measurement value of time of arrival t n , performing cubic polynomial fitting on the line of sight angle alpha n by using a least square method to smooth measurement error; performing quadratic polynomial fitting on the time of arrival t n by using a least square method to obtain a linear term coefficient p1 and a quadratic term coefficient p2; obtaining a radar pulse repetition interval T by using a statistical pulse time of arrival difference; updating a detection pulse serial number n; solving a radar initial distance r0; and solving a radar flight speed v and a flight direction beta by using the initial distance r0, the direction of arrival alpha n and the time of arrival t n . The application has the characteristic that a signal waveform of a SAR emission is synthesized with an LFM pulse, accurate estimation of SAR motion parameters is realized, the variation rate parameter of the line of sight angle is avoided, and the robustness of the algorithm is improved and the requirement for the direction finding accuracy is reduced.

The invention belongs to the technical field of permanent magnet synchronous motor control, and discloses a sensorless control method and device for a permanent magnet synchronous motor, and the method comprises the steps: building a super-spiral sliding-mode observer, introducing an observation error linear term in the super-spiral sliding-mode observer, and constructing a second-order sliding-mode model; constructing a back electromotive force adaptive optimization module in the super-spiral sliding mode observer by adopting a complex coefficient filter; constructing a phase-locked loop by adopting a fourth-order active-disturbance-rejection algorithm, and estimating a rotor position error in real time by adopting a state expansion observer; a primary linear expansion state observer and a secondary linear expansion state observer are connected in series to form an improved linear active disturbance rejection controller. According to the method, buffeting of the sliding-mode observer can be suppressed, and the counter electromotive force estimation precision is improved; the dynamic response capability of the system under the working conditions of medium-high speed and sudden loading is enhanced, the method is more suitable for complex working conditions of high speed, variable load and the like, and the robustness and the control precision of the system are remarkably improved.

The invention discloses a high-dimensional feature screening method and device based on quantum annealing, relates to the technical field of quantum computing, and realizes accurate and efficient feature screening in a high-dimensional financial data scene. The method comprises the following steps: acquiring data of a target financial variable and data of a to-be-preliminarily screened characteristic factor; constructing an initial total prediction linear term based on a linear term of the secondary unconstrained binary optimization model, and obtaining a selected to-be-primarily-screened characteristic factor as a to-be-finely-screened characteristic factor; based on a linear term and a quadratic term of the quadratic unconstrained binary optimization model, constructing a total prediction linear term and a redundant quadratic term, and obtaining a selected to-be-finely screened characteristic factor as a to-be-optimized characteristic factor; the permutation importance of each to-be-optimized feature factor is calculated, a target feature factor is screened from the to-be-optimized feature factors according to the permutation importance, and the target feature factor is used for predicting a target financial variable.

The application relates to a Hammerstein dynamic hysteresis model based on an improved asymmetric generalized Prandtl-Ishlinskii model, relates to the technical field of servo control, and comprises the following steps: introducing a double exponential function of a deviation factor and adding a linear term in an envelope function; based on the double exponential function envelope with the deviation factor, an improved asymmetric generalized Prandtl-Ishlinskii model is constructed according to a formula; an ARX model structure is adopted to capture the dynamic linear characteristics of a system; the improved asymmetric generalized Prandtl-Ishlinskii model is taken as a static nonlinear part of a Hammerstein model, and an ARX dynamic model is taken as a dynamic linear part of the Hammerstein model; and the output of the Hammerstein dynamic hysteresis model is used to verify the results and application cases. The application improves the existing asymmetric generalized Prandtl-Ishlinskii model, introduces the double exponential function envelope with the deviation factor, and can more accurately describe the asymmetric hysteresis characteristics.

The invention relates to a fluid-structure interaction dynamics simulation test method and system for a canopy and an optimization method. The simulation test method comprises the following steps: dispersing the canopy into a mass-spring-damping grid model; defining an elastic force expression containing a linear term and a nonlinear term for the spring unit, and calibrating a key coefficient through a material test or an empirical formula; establishing a control equation containing nonlinear elastic force, damping force and aerodynamic force; and fluid-structure interaction numerical solution is carried out, and the whole-process dynamic behavior of the canopy from parachute opening to stable descending is simulated. The optimization method comprises the steps of comparing a simulation result with a design index, and adjusting a local design parameter based on a diagnosis result and performing iteration until a requirement is met. The simulation precision and reliability of large-deformation nonlinear response, aerodynamic performance and complex fluid-solid coupling phenomena of parachute canopy fabric are remarkably improved, and an effective numerical simulation tool is provided for design optimization of flexible structures such as supersonic parachutes.

This invention discloses a method and system for predicting circular induction synchronizer errors based on a hybrid model. The method relates to the field of precision measurement technology and includes obtaining target position-error data; constructing a circular induction synchronizer error prediction model based on the normalization principle, first harmonic linear terms, radial basis function neural network terms, dynamic parameter optimization mechanisms, and the principle of linear superposition; and inputting the target position-error data into the circular induction synchronizer error prediction model to obtain a predicted error value. This invention addresses the issues of positioning misalignment, poor real-time performance, and weak generalization capabilities in high-precision servo systems caused by temperature drift and complex interference. It achieves efficient and reliable embedded real-time correction of circular induction synchronizers, improving the accuracy of circular induction synchronizer error prediction.

The present application discloses transcendental function evaluation. In the described example, an apparatus 500 is arranged to generate a linear term, a quadratic term, and a constant term of a transcendental function in response to the least significant bit of an input operand 510 and in response to first, second, and third table 520 values, respectively, using first circuit 530, second circuit 550, and third circuit 580, respectively. The first, second, and third table 520 values are retrieved in response to first, second, and third indices, respectively, which are generated in response to the most significant bit of the input operand. The third circuit 580 is further arranged to generate a mantissa of an output operand in response to the sum of the linear term, the quadratic term, and the constant term.

The present invention discloses a forward solution algorithm for a parallel mechanical platform based on polynomial regression, comprising the following steps: Step 1: constructing a six-variable cubic polynomial as follows: #imgabs0# wherein: is the parameter to be solved, A is the cubic coupling term parameter of 1, B is the quadratic coupling term parameter of 1, C is the linear term parameter of 1, and D is a constant parameter; Step 2: kinematically inversely solving the known posture parameters to obtain the corresponding robotic arm length, and then eliminating the remaining unknowns except for the parameters A, B, C, and D in the above formula; Step 3: establishing a set of 259 linear equations for solving A, B, C, and D, solving the linear equations, and obtaining the values of A, B, C, and D. The present invention solves the problems of non-globality and poor real-time performance of Newton iteration in kinematic forward solution problems, and can be used in a multivariate polynomial regression forward solution algorithm for a parallel mechanical platform. The polynomial regression method can converge globally and has stronger real-time performance.

The invention discloses transcendental function evaluation. In described examples, an apparatus 500 is arranged to generate a linear term, a quadratic term, and a constant term of a transcendental function responsive to least significant bits of an input operand 510 and responsive to first, second, and third table 520 values, respectively, using first, second, and third circuits 530, 550, and 580, respectively, the first, second, and third table 520 values are retrieved in response to first, second, and third indices, respectively, generated in response to most significant bits of the input operand. The third circuit 580 is further arranged to generate a mantissa of the output operand in response to a sum of the linear term, the quadratic term and the constant term.

The present application provides a communication method and a communication apparatus. In the solution, a first device determines a polynomial exponential sequence, wherein the degree of the polynomial exponential sequence is greater than or equal to 2, and at least one of a quadratic term coefficient, a linear term coefficient, or a zero-term coefficient of the polynomial exponential sequence is associated with an index of an element of the polynomial exponential sequence. In this way, by designing the relationship between a coefficient of a polynomial exponential sequence and an index of an element, the interference between a plurality of polynomial exponential sequences can be reduced, so that a large-capacity and relatively low-interference non-orthogonal polynomial exponential sequence is provided.

The present invention belongs to the field of rapid calculation of multi-physical fields of power equipment, and discloses a rapid analysis and calculation method for magnetic fields under transformer short-circuit faults and related devices: the method comprises the following steps: calculating the vector magnetic potential of the first several time steps through a full-order calculation model of the transformer short-circuit magnetic field in a high-dimensional space; constructing a snapshot matrix of a solution vector and a snapshot matrix of nonlinear terms; obtaining a set of orthogonal bases based on an intrinsic orthogonal decomposition method and in combination with the snapshot matrix of the solution vector; constructing a reduced-order subspace using the orthogonal bases; projecting the full-order calculation model of the transformer short-circuit magnetic field into the reduced-order subspace; obtaining an interpolation matrix of the nonlinear terms based on a discrete empirical interpolation method and in combination with the snapshot matrix of the nonlinear terms; updating the nonlinear terms in the reduced-order calculation model of the transformer short-circuit magnetic field using the interpolation matrix, and then calculating the vector magnetic potential in the reduced-order subspace; reconstructing the vector magnetic potential back into the high-dimensional space, and calculating the magnetic field under the transformer short-circuit fault using the reconstructed vector magnetic potential.

The design method of the non-linear term offset moving coil magnetic single-acting vibrator meets the following conditions: (1) a moving coil magnetic single-acting vibrator body comprises an outer cylinder, a vibration transmission sheet, a stator assembly and a rotor assembly; (2) 2N magnetic domains D1, i and D2 which are designed in pairs are arranged in the moving-coil magnetic single-acting oscillator body, i and N are 1, 2, 3,..., 100, and i = 1, 2, 3,...; and (3), the mover assembly is subjected to electromagnetic acting force of pushing force and pulling force in pairs at the same time, the push-pull type structural characteristic is presented, the mover assembly is subjected to interaction of the pushing force and the pulling force, linear terms in component force of the mover assembly are overlapped and become large, and the linear terms in the component force of the mover assembly become large. And non-linear terms in the component force of the mover assembly are partially or completely counteracted and are reduced.