228 results about "Newton's method" patented technology

A computerized system and method for large scale semi-supervised learning is provided. The training set comprises a mix of labeled and unlabeled examples. Linear classifiers based on support vector machine principles are built using these examples. One embodiment uses a fast design of a linear transductive support vector machine using multiple switching. In another embodiment, mean field annealing is used to form a very effective semi-supervised support vector machine. For both these embodiments, the finite Newton method is used as the base method for achieving fast training

A system and method for implementing a maximum likelihood estimator for making a joint estimation of range, range rate, and acceleration of a target utilizing a pulse doppler radar. The MLE of target motion parameters are determined by keystone processing a baseband signal, and generating a first estimate of the motion parameters based on the processed signal. The first estimate is utilized to set up sampling intervals for the performance of a coarse search. Then a fine search is performed using Newton's method to determine the MLE.

A computerized system and method for large scale semi-supervised learning is provided. The training set comprises a mix of labeled and unlabeled examples. Linear classifiers based on support vector machine principles are built using these examples. One embodiment uses a fast design of a linear transductive support vector machine using multiple switching. In another embodiment, mean field annealing is used to form a very effective semi-supervised support vector machine. For both these embodiments the finite Newton method is used as the base method for achieving fast training.

The invention relates to a longitudinal-transverse-vertical force cooperative control method of a distributed electrically driven vehicle. The method is implemented by a vehicle control system: 1) formulation of expected resultant force and moment; 2) optimal distribution of longitudinal, transverse and vertical forces of four wheels; 3) specific execution of the forces. The expected values of the resultant force and the moment of the whole vehicle are obtained by utilizing various information of the vehicle, an integrated tyre force optimization problem is formed by establishing a constraint condition and an objective function, and an optimization solution algorithm is designed for the problem, wherein the optimization algorithm comprises a constraint optimization method which adopts a barrier function method and a Newton method, and a feasible region planning method based on vehicle state continuity. The method does not need to implement different control strategies according to different work conditions of tyres, realizes unified optimal distribution and control of the longitudinal, transverse and vertical forces of the tyres, comprehensively improves the operation stability and the driving posture of the vehicle, and can be applied to driverless operation of vehicles in the future.

The invention relates to an inversion method of nuclear magnetic resonance two-dimensional spectrum. The method includes firstly, extracting and estimating noise, namely extracting noise in CPMG (Carr-Purcell-Meiboom-Gill) echo string of acquired data and estimating standard deviation of the noise; secondly, compressing data, namely generating an inversion kernel and performing truncated singular value decomposition and reconstruction by sequence of a nuclear matrix to complete data compression; and thirdly, fitting the data, namely subjecting fitting problem of the compressed data to regularization, performing iterative solution to regularization factors and inversion spectrum by newton method with non-exact one-dimensional search so as to obtain the inversion spectrum. Execution efficiency of two-dimensional inversion algorithm and resolution of two-dimensional spectrum are increased greatly, and the inversion method is well robust.

The invention discloses a power system short-term load forecasting method based on improving extreme learning machine (IELM) methods, which adopts an extreme learning machine (ELM) as the basic structure of a forecasting model and is an iteration-analysis learning algorithm which puts forward BFGS (Broyden, Fletcher, Goldfarb, Shanno) simulated Newton's method to give optimization, training and adjustment to network left metrics and analyze to get right metric parameters. The invention establishes the short-term load forecasting model based on improving extreme learning machine (IELM) method, puts forward extreme learning machine network reference hidden node concepts, trains the equidimensional extreme learning machine networks which have the same numbers of hidden nodes and samples, orderly clusters module values of equidimensional network right metrics vector, finds out a plurality of corresponding module value break points, and regards the break points as the reference hidden nodes of predicting networks. The method of the invention is also greatly improved in the aspect of prediction precision and speed.

The invention discloses a modeling and optimized dispatching method of an electrical series-parallel system on the basis of an energy center. The modeling and optimized dispatching method comprises the following steps: firstly, establishing an electrical network, a natural gas network and an energy hub model, and coupling the electrical network with the natural gas network through an energy hub to form the electrical series-parallel system; then, taking total energy cost as a target function, and considering various constraint conditions to establish an optimized dispatching mathematic model of the electrical series-parallel system; and carrying out solving by a primal-dual interior-point method, importing a slack variable and a barrier parameter in sequence in a solving process so as to change the model into a model which only contains an equality constraint, then, importing a Lagrange multiplier to obtain a Lagrange function, and solving a non-linear equation set formed by a KKT (Karush-Kuhn-Tucker) condition of the Lagrange function by a Newton method. A constructed example simulation result indicates that an optimization effect on the electrical series-parallel system by the modeling and optimized dispatching method is superior to an independent optimization effect.

The invention discloses a rectangular coordinate Newton method load flow calculation method with a changeable Jacobian matrix. The method includes the following steps that original data input and voltage initialization are conducted; a node admittance matrix is formed; power and voltage deviations are calculated, and the maximum amount of unbalance delta Wmax is obtained; the Jacobian matrix J is formed; a correction equation is solved and a real part e and an imaginary part f of voltage are corrected; node and circuit data are output. According to the rectangular coordinate Newton method load flow calculation method, a Jacobian matrix calculation method different from that used in the following iteration processes is adopted in the initial iteration process, and the convergence problem of rectangular coordinate Newton method load flow calculation in analyzing a system with a small-impedance branch circuit is solved. When misconvergence happens with conventional rectangular coordinate Newton method load flow calculation, the rectangular coordinate Newton method load flow calculation method with the changeable Jacobian matrix can achieve reliable convergence, and the number of iterations is fewer compared with the prior art. The rectangular coordinate Newton method load flow calculation method with the changeable Jacobian matrix can effectively solve the convergence problem of the conventional rectangular coordinate Newton method load flow calculation in analyzing the system with the small-impedance circuit branch, and meanwhile load flow calculation can be performed on normal systems, and adverse effects are avoided.

The invention discloses a method for calculating the probability power flow of a power system containing a wind farm. The method comprises the following steps of: 1, calculating the power of the wind farm and probability distribution of load power; 2, calculating deterministic power flow of the power system containing the wind farm by a Newton method, and solving a sensitivity matrix S0; 3, calculating the each-order cumulant of each node injection vector; 4, solving the each-order cumulant of a state variable according to the each-order cumulant of the injection vector; and 5, solving a probability density function and a cumulative distribution function according to Gram-Charlier series expansion. By the method, errors caused by solving through a cumulant method when the wind farm is processed as a simplified PQ model with a constant power factor can be effectively reduced.

Spinal modeling is based on a concept called spinal energy which assumes that the spine assumes a shape to minimize spinal energy. Spinal energy depends on parameters called stiffness coefficients. These parameters can be determined from human data which, by hypothesis, are universal for a large class of humans. The method adapts Newton's method to the manifold SO(3)<n >to find a solution of model of the human spine. Where basins of attraction are small in Newton's method, homotopy methods are introduced to move from known solutions to unknown solutions. By setting the gradient of the spinal energy to zero, Newton's method is used to solve the inverse problem of finding stiffness coefficients from human data. A new approach to improving deformed spines uses the modeling method based on spinal energy. This approach preserves maximally the range of motion of the spine. The technique used is vertebraplasty; i.e., adding and / or subtracting material surgically from various vertebral bodies without fusing or altering soft tissue. An interactive process is used to determine the surgery to be performed to improve spinal shape.

The invention discloses a quick algorithm for joint resource allocation in a heterogeneous wireless network parallel multi-access system. When the joint resource allocation is performed in the heterogeneous wireless network parallel multi-access system, the bandwidth and power allocations are separated and the resource allocation is performed in turn, wherein the bandwidth allocation under the condition of equal power allocation is firstly performed; in the bandwidth allocation process, the advantage of high convergence rate of a Newton method is fully taken, thereby reducing the arithmetic complexity and increasing the arithmetic rate; and then the power allocation is performed; and if a power allocation result is a negative value, the bandwidth and the power are allocated again, thereby more fully utilizing the bandwidth and power resources as well as increasing the arithmetic efficiency and rate. By utilizing the algorithm to perform the joint resource allocation in the heterogeneous wireless network parallel multi-access system, the purpose of approaching the acquired resource allocation optimal solution to the theoretical optimum solution is achieved. The algorithm can be used for quickly allocating the joint resource in the heterogeneous wireless network parallel multi-access system.

The invention discloses a load flow calculation method of a rectangular coordinate newton method. The load flow calculation method comprises the following steps: inputting original data and initializing a voltage; forming a node admittance matrix; calculating power and a voltage deviation; forming a jacobian matrix J; solving a modified equation and modifying a real part e and an imaginary part f of the voltage; and outputting nodes and branch data. The calculation formula of partial elements (i=j) of the jacobian matrix obtained in a manner of load flow calculation by utilizing the rectangular coordinate newton method is modified and improved, so that the problem of astringency of the load flow calculation of the rectangular coordinate newton method during the analysis of branch systems containing small impedance is solved. As compared with the fact that the astringency of the small impedance branch systems cannot be realized by adopting the load flow calculation of the conventional rectangular coordinate newton method, the reliable astringency of the small impedance branch systems can be realized by utilizing the load flow calculation disclosed by the invention; and the load flow calculation to normal systems can be carried out at the same time, so that harmful effects are avoided.

The invention provides a pseudo-range differential positioning method of a long base line. A plurality of satellites, a user terminal and a base station form a satellite navigation pseudo-range differential model. A pseudo-range single-different equation relative to one same satellite is constructed by using pseudo-range observation equations of the base station, the user terminal, and the satellites; with pseudo-range single-different equations of different satellites, a non-linear pseudo-range dual-difference equation group containing multiple satellites is constructed; and then a position of the user terminal is obtained by using the Newton's method and the method of least squares. According to the positioning method, errors of the pseudo-range differential positioning model under base lines with different lengths can be eliminated and thus the increase with increasing of the length of the base line is prevented, so that a small error range can be kept and thus a high-precision positioning requirement can be completely met.

The invention discloses a Newton method power flow calculation method which changes a Jacobi matrix with iteration and node types. A PQ node calculates a Jacobi matrix element by using an ai value and a bi value which are calculated by given values Pis and Qis in the first-time iteration. A PV node and all nodes in the subsequent iteration calculates the Jacobi matrix element by using a conventional method. The method solves a convergence problem of a rectangular coordinate Newton method power flow calculation method in the analysis of a power system containing a low impedance branch in such a way that the PQ node adopts the Jacobi matrix calculation method in the first iteration process and which is different from that in the subsequent iteration processes. The method of the invention can be reliably converged when he conventional rectangular coordinate Newton method are not convergent, is less than the number of iterations than the prior art. The Newton method power flow calculation method can not only solve the convergence problem of the rectangular coordinate Newton method power flow calculation method in the analysis of a power system containing a low impedance branch, but also can calculate the power flow of the normal power system without any adverse effect.

The invention discloses a distributed computation based voltage stability assessment method of sub-networks in an interconnected power network. The distributed computation based voltage stability assessment method comprises the following steps: firstly establishing a simplified external network model which only reserves a regional interconnection line on sub-networks in the interconnected power network; then calculating load margin by a continuation power flow (CPF) method in the main sub-network performing voltage stability assessment calculation, and then calculating by a Newton load flow method under coordination of the other neighboring sub-networks; and by means of voltage information exchange and coordination calculation of boundary nodes in outer loop, continuously correcting equivalent injection power of the boundary nodes outside the sub-networks so as to finally and locally obtain the sub-network load margin which is consistent with the result of whole network unified computation at the main sub-network. The voltage stability assessment method has the beneficial effects that by adopting the simplified external network model of the sub-networks, the Ward equivalent process is avoided so as to reduce the participation degree and calculated quantity of a coordination layer; the calculation mode is basically consistent with that in the current EMS (energy management system), and the independent calculation precision of each sub-network is higher; and voltage stability support and impact of an external power network on an internal power network can be better considered.

A method for analyzing limit pretension force of an angular contact ball bearing under fixed-position pretension of a high-speed electric spindle belongs to the technical field of bearing pretension. According to the method, firstly, parameters including a bearing type, a working condition, maximum permissible stress of a material and the like are determined; secondly, based on a Hertz contact theory, the influences of pretension force, centrifugal force and gyroscopic torque of the bearing are considered, and a kinetic model of the angular contact ball bearing under the fixed-position pretension is established, wherein the kinetic model includes a contact region model of the angular contact ball bearing, a pretension model of the angular contact ball bearing in a static state of the spindle, and a pretension model of the angular contact ball bearing in a rotating state of the spindle; thirdly, a relation between the pretension force and maximum contact stress of a bearing rolling body and bearing inner and outer rings under the condition of rated speed is solved with a Newton method; and finally, the pretension force, i.e., the limit pretension force, of the bearing under the permissible stress of the material is analyzed out.

The present invention provides a five-axis machining track contour error double closed-loop compensation method, belongs to the multi-axis numerical control process technology field, and relates to a contour error double closed-loop compensation method configured to improve the five-axis machining precision based on inner ring prediction compensation and outer ring feedback compensation of contour errors. Based on model prediction and feedback correction, the method estimates motion position of each physical axis at the next moment, employs tangential inversing and the Newton's method to calculate tip point contour errors and cutter axis direction contour errors of the next moment and the current moment, and the contour errors are subjected to prediction compensation at the inner ring and the contour errors are subjected to prediction compensation at the outer ring according to inversed Jacobian matrix so as to improve the five-axis machining track contour precision. The five-axis machining track contour error double closed-loop compensation method inhibits the residual errors caused by outside disturbance and model errors on the basis of realizing control of the five-axis machining contour errors in advance so as to have important meanings for improving the five-axis numerical control machining precision.

The invention discloses a rectangular coordinate Newton load flow calculation method; from the basic principle of rectangular coordinate Newton load flow calculation, the invention provides a composition method of Jacobimatrix calculated by rectangular coordinate Newton load flow calculation to improve the convergence of load flow calculation on the basis of analyzing the characteristics of basic modified equation. The method comprises the following steps: inputting original data and initializing voltage; forming nodal admittance matrix; forming Jacobimatrix J; solving the equation and correcting the real part e and the imaginary part f of voltage; and outputting nodal and subcircuit data. The invention corrects partial diagonal element calculation formula of Jacobimatrix J, solving the problem of convergency of rectangular coordinate Newton load flow calculation method when analyzing a subcircuit system containing low impedance; the iterations, possession of the amount of internal memory and arithmetic speed in the invention are all equivalent to conventional rectangular coordinate Newton load flow calculation method when treating system with no low impedance, so the calculated amount is not increased, but is slightly reduced on the contrary.

A stable and accurate reactor physics thermotechnical coupling calculating method can simultaneously obtain statuses of a neutronics field, a fluid field and a heat transfer field; all variables are simultaneously updated in an iteration process, so the method has better value stability when compared with a conventional coupling method; the method uses a simultaneous time-space neutron diffusion equation and a thermotechnical equation discrete equation to obtain a novel nonlinear equation group with larger scale; using a Newton iterative method to resolve values of the novel nonlinear equation group, wherein the Newton iterative method needs to calculate a Jacobian matrix of the equation group in each iteration step, so physics thermotechnical coupling calculation is difficult. The novel method builds a value relation between the diffusion equation and thermotechnical equation, and explicit calculation can provide the Jacobian matrix, so problems caused by approximation calculation f the Jacobian matrix can be prevented; in addition, the novel method inherits Newton method characteristics, and hopes to provide faster convergence speed.

The invention discloses a polar coordinate Newton method load flow calculation method based on a Matlab sparse matrix, adopting matrix operation and complex operation and using a sparse matrix technology provided by Matlab. The method is implemented on a Matlab platform, so that researchers are facilitated to use various tools and functions provided by Matlab to test and analyze a calculation method. The main part of the method adopts both the matrix operation and the complex operation, reduces program codes and simplifies a programming process, so that the program is clearer, and the researchers are facilitated to modify the program, debug the program, and improve and add new functions for the program. The method provided by the invention adopts the sparse matrix technology of Matlab, so that calculation speed is greatly improved, meanwhile the sparse matrix of Matlab is very convenient to use, elements of the sparse matrix can be directly used by using a column number like a full matrix, design of a sparse storage structure is not needed, and an excellent analysis tool is provided for scientific research of the researchers.

The embodiment of the invention provides a joint training method and device for a business model. In the process of multi-party joint training of a service model, in order to train a service model ata higher convergence speed by using a Newton method, when an inverse matrix of a Hessian matrix is determined, an auxiliary matrix generated by a trusted third party is introduced, products of the Hessian matrix and the auxiliary matrix are determined by all service parties of a joint training service model in a secret sharing mode, and corresponding shares are obtained respectively. And then, thecombination result of the product of the Hessian matrix and the auxiliary matrix is disclosed, so that each business party obtains the inverse matrix of the combination result, and the correspondingshare of the inverse matrix of the Hessian matrix is determined. According to the specific business party interaction mode setting, it is feasible to adjust model parameters by using a Newton method in multi-party security calculation on the premise of ensuring data privacy, so that the joint training efficiency of a business model is improved.

The invention provides an alternating-current and direct-current power distribution network system load flow computing method based on droop control. The method includes the following steps that firstly, initialization computing of a sagging curve is carried out; secondly, direct-current power of a direct-current power distribution system is updated through the Newton algorithm; thirdly, according to the updated direct-current power, a middle node voltage equation of an alternating-current power distribution system is solved, and droop characteristics are led into the alternating-current power distribution system; fourthly, whether alternating-current power flow and direct-current power flow converge or not is judged, if no, the second step continues for iterative computation till the alternating-current power flow and the direct-current power flow converge at the same time, and meanwhile a result is output. The invention provides the power flow mixing computing method suitable for a multi-terminal interconnection alternating-current and direct-current power distribution system adopting droop control, the gauss algorithm is adopted in the alternating-current power distribution system, and the Newton algorithm is adopted in the direct-current power distribution system. Meanwhile, the advantage that the gauss algorithm is little in calculation quantity and the advantage that the Newton algorithm is good in convergence are both taken into consideration, the problem that power flow does not converge is avoided, and the practicality level of power flow computing is improved.

The invention discloses a frequency selectivity MIMO (multiple input multiple output) system space-time blind equalizer method based on a MNM (modified Newton method). The method comprises the following steps that firstly, a multimode method and a soft decision guide method are combined for building a cost function; then, a batch processing mode is adopted, the training sequence length is selected, and the initial value of the blind equalizer is estimated from the known emitted data and the corresponding observing data by a least square method; a newly provided MNM is utilized for calculating the optimal equalizer from observing samples; and finally, the equalizer is utilized for evenly receiving signals, the interference among signals and the interference among codes are eliminated, and resources signals are recovered. The method overcomes the defects that when the exiting MNM is applied to a MIMO system, the calculation quantity is great, and the equalization precision of the existing blind equalization algorithm is low. Compared with the exiting method, the method has the advantages that MNM, MMA and SDD only need little training sample data, and the equalizer can be enabled to be correctly converged to the optimum MMSE (minimum mean square error) equalizer.

The present invention discloses a Matlab sparse matrix-based Cartesian coordinate Newton power flow calculation method. Matrix operation and complex operation are adopted, and a sparse matrix technique provided by the Matlab is used. The method of the invention is realized on the Matlab platform, so that scientific researchers can be facilitated to use various tools and functions provided by the Matlab to test and analyze calculation results; and the main part of the method of the invention adopts the matrix operation and complex operation, and therefore, program codes can be reduced, programming is simplified, a program is more clear, the scientific researchers can be facilitated to modify, debug and improve the program and add new features. The sparse matrix technique of the Matlab and the matrix operation are adopted, and therefore, calculation speed can be greatly improved; and the sparse matrix of the Matlab is very easy to use, and line and column numbers can be adopted to directly use the elements of the sparse matrix just as a full matrix, and an excellent analytical tool is provided for the scientific research work of the scientific researchers.

The invention discloses a low-speed impact locating method for a composite material cell structure, and belongs to the field of composite material structure engineering structure health monitoring. According to the method, an unconstrained optimization algorithm based on a Newton method is applied to solving the low-speed impact recognition problem of the composite material cell structure, and the low-speed impact fast recognition of the structure is achieved. Based on a sensor array technology, impact induction is applied to the structure to generate Lamb wave signals, and impact response signals of the composite material cell structure are collected. A certain sensor is used as the criterion, the wavelet analysis means is adopted, and the time differences of Lamb waves reaching the other sensors are extracted. The unconstrained optimization algorithm based on the Newton method is adopted to solve and locate a system of nonlinear equations, and therefore the position of an impact source is obtained. The impact source of the composite material cell structure can be recognized fast and effectively, recognition precision is high, and good engineering application value is achieved.

The invention, which belongs to an electric power system scheduling automation and electric power system simulation technology field, relates to a zero-injection-constraint electric power system state estimation method based on a modified Newton method. The method is characterized by: establishing a state estimation model; carrying out an iterative solution to the state estimation model accordingto the common Newton method; in the each iteration, correcting a state variable of a nonzero injection node according to a calculation result of the common Newton method; however, acquiring the statevariable of the zero injection node by using a relationship between the zero injection node state variable established by the zero injection equality constraint and the nonzero injection node state variable and not by taking the calculation result of the common Newton method. A whole calculating process of the invention is similar to a traditional state estimation calculating flow. Realization is convenient. Simultaneously, an injection power of the zero injection node can be guaranteed to be zero. The state estimation result strictly satisfies a trend equation.

The invention discloses a deep learning target detection method. The method comprises the following steps: inputting a picture, and extracting features of a target in the picture through a convolutional neural network backbone network; firstly, generating a plurality of sliding windows with different scales and length-width ratios through a regional candidate network, and then obtaining candidateboxes possibly containing targets through classification and frame regression operation; mapping to a feature layer of a target to be detected through the candidate box, and performing pooling operation on an interested target area to obtain a pooled feature map with the same dimension of the target area; respectively performing classification and frame regression operations on the feature layer of the target to be detected; and obtaining a final target detection box after non-maximum suppression. The method has the advantages that the problem that the target function of the detection networkcannot be optimized when the prediction frame and the real frame are not overlapped is avoided; a Newton method can be used to update network weight, and detection network training is faster. High target detection result accuracy is realized.

The invention provides a frequency domain visco-acoustic medium full waveform inversion method, which comprises the steps of using a truncated Newton method to perform a joint inversion on velocity and a Q value, and selecting an optimized hybrid interleaving difference format to discretize a wave equation. The method of the invention improves the artifact phenomenon and improves the effect and efficiency of the joint inversion.

The invention discloses an improving method of energy flow calculation of a natural gas system. The method comprises the following steps: firstly, inputting network parameters of the natural gas system to establish a natural gas system energy flow calculation model; optimizing the initial value of the natural gas system by means of a genetic algorithm; and finally, calculating the energy flow of the natural gas system by means of a Newton method. By combining global search of the genetic algorithm and local searching abilities of the Newton method, the problem of selecting the initial value of natural system energy flow calculation is effectively solved.