68 results about "Minimum principle" patented technology

The invention discloses a spectrum reconstruction method and system based on a multichannel imaging system, which are used for performing spectrum reconstruction according to the camera response values of a training sample to-be-selected set and a to-be-reconstructed sample set acquired by the multichannel imaging system. The method comprises the following steps: selecting training samples with most similar camera response values from the training sample to-be-selected set for each to-be-reconstructed sample in the to-be-reconstructed sample set respectively to obtain an initially-selected sample set; removing identical samples, and constructing a matrix by the spectral reflectivity information of all samples to perform PCA (Principal Component Analysis) analysis; computing the accumulating contribution rate of a characteristic value; screening the samples to obtain a training sample sub-set, performing spectrum reconstruction according to each training sample sub-set for each to-be-reconstructed sample, and selecting one reconstruction result according to a reconstruction error minimum principle for serving as the final spectral reflectivity value of each to-be-reconstructed sample. By adopting the spectrum reconstruction method and system, the chromaticity accuracy and spectrum accuracy of each reconstructed sample can be remarkably increased, and high-fidelity color reproduction can be performed. Meanwhile, the method and the system are easy and convenient to implement, and are suitable for popularization and application.

The invention discloses a block segmentation method for a triangular grid model. The method comprises the steps of reading the triangular grid model and establishing topological information; calculating a concave-convex signal of a vertex of the triangular grid model and performing global Laplace smooth denoising; calculating standardized concave-convex information to obtain a concave characteristic region of the grid model; calculating normalized concave-convex information and reducing the concave characteristic region; extracting a center line of the reduced concave characteristic region; constructing a closed segmentation line by adopting a sector probe ray algorithm; optimizing the segmentation line by adopting a three-dimensional snake method and performing fitting and smoothing on the segmentation line; and segmenting the triangular grid model by adopting a regional growth method. According to the method, the segmentation line meeting a minimum principle in the triangular grid model is extracted for efficiently and reliably segmenting the model into minimum rule sub-blocks meeting the visual requirements.

The present invention is a method for extracting electromagnetic parameters of artificial electromagnetic material based on support vector machine (SVM). The invention relates to a new method for researching electromagnetic parameter measurement, capable of testing shield-hand material and artificial electromagnetic material having a periodic structure, and the testing result precision is high andthe production of testing samples is simple. The support vector machine (SVM) method is based on a VC-dimension theory of a statistical learning theory and a structure risk minimum principle, seeks an optimum compromise between the complexity and the learning capacity of a model based on limited sample information so as to obtain best popularization capability, and is widely applied to statistical classification and regression analysis. According to the invention, transmission and reflection coefficients of material to be tested are calculated by numerical computation methods FEM and FDTD ofelectromagnetism, and the corresponding computed result is used as training sequences to train the the support vector machine. When the support vector machine is trained fully, it is capable of calculating equivalent dielectric constant and equivalent magnetic conductance of the material to be tested by inputting testing values of the transmission and reflection coefficients.

The invention discloses a method for extracting bearing fault characteristic frequency through information-entropy optimized VMD and application thereof. The method for extracting the bearing fault characteristic frequency through the information-entropy optimized VMD includes the steps that firstly, according to the information entropy minimum principle, the modal number of VMD is optimized, andthe optimized modal number is adopted to optimize the penalty factor of the VMD according to the information entropy minimum principle; then, the optimized modal number and penalty factor are adoptedto conduct VMD on bearing original vibration signals to obtain IMF components of the vested modal number, and through comparison, the IMF component where the information-entropy minimum is located canbe obtained and serve as a sensitive IMF component; finally, the selected IMF component is subjected to envelope demodulation analysis to extract the bearing fault characteristic frequency. By the adoption of the method for extracting the bearing fault characteristic frequency through the information-entropy optimized VMD, the bearing fault characteristic frequency can be effectively extracted; the method for extracting the bearing fault characteristic frequency through the information-entropy optimized VMD is applied to analyzing bearing simulation signals and actual bearing signals and hasrelatively broad practicability.

The invention relates to a method for segmenting a sulus region on the surface of a pallium of a three-dimensional cerebral magnetic resonance image. The technical characteristics lie in that firstly, the 3D cerebral nuclear magnetic resonance image is pretreated and the surface of the pallium is reconstructed, including removing a braincase and non-cerebral tissues; carrying out cerebral tissue segmenting on a cerebral image and reconstructing the surface of the pallium of geometrical accuracy and correct topological structure in the segmented cerebral image; the surface of the pallium is shown by a series of vertexes and triangles; secondly, the maximum principle curvature and the minimum principle curvature of each vertex on the surface of the pallium are estimated; and finally, sulus and gyrus regions are segmented on the surface of the pallium according to the maximum principle curvature and Hidden Markov Random Field expectation maximization framework and each sulus region is marked by connectivity analysis. Compared with other methods, the method has the advantages of simple and effective algorithm and high segmentation accuracy.

The invention discloses an actuator product acceleration factor determining method based on theoretical lifetime calculation. The method comprises the specific steps that (1) conducting main mechanism analysis, wherein actuator product weak links and main mechanisms corresponding to the actuator product weak links are determined; (2) selecting lifetime calculation models, wherein the corresponding lifetime calculation models are selected according to the types of the main mechanisms; (3) comprehensively determining acceleration factors, wherein the acceleration factors, corresponding to the product weak links, of the main mechanisms under different stress levels are calculated according to the determined stress types and ranges, the acceleration stress level is determined according to the acceleration factor standard deviation minimum principle, and the acceleration factors are determined according to the acceleration factor minimum principle. The actuator product acceleration factor determining method can be directly applied to products, the acceleration factors of the products are determined through the acceleration factors of the product weak links obtained through main mechanism analysis calculation, theoretical supports are provided for a product layer acceleration lifetime test method, and the actuator product acceleration factor determining method has the advantages of being clear in thought, high in operability and the like.

The invention discloses a driver-in-the-loop vehicle fuel economy control method. The method is characterized in that a vehicle is an intelligent network connection hybrid power vehicle, and the control method is a hierarchal control method in which driver random errors are considered; a superior control method in the hierarchal control method calculates an optimal target vehicle speed based on the driver random errors and state information obtained based on an intelligent network connection environment, wherein the state information comprises surrounding vehicle state information and trafficlight state information; a substratum control method in the hierarchal control method calculates the optimal energy distribution of the hybrid power vehicle based on a self-adaption equivalent fuel consumption minimum principle. According to the control method, a preset vehicle speed which is very approximate to an ideal condition can be obtained, and better fuel economy is obtained.

The invention discloses an optimal predicative direct power control method of a doubly fed induction generator. The method includes the steps that two effective voltage vectors and one zero vector are applied in each control period, one voltage vector is selected to obtain a switching list according to the predicted change conditions of active power and reactive power and the stator flux linkage positions when different control behaviors are applied, and the action time of the selected voltage vector is calculated according to the power tolerance minimum principle in the control periods; when the action time of the voltage vector obtained through calculation is negative, the voltage vectors are reselected to calculate the action time. Therefore, accuracy and effectiveness of the selected voltage vectors and the action time are guaranteed, and the active power and the reactive power of a doubly fed power generating system are independently and effectively controlled. By the adoption of the optimal predicative direct power control method, low-order current harmonics can be reduced, constant switching frequency is achieved without converting rotational coordinates and modulating the space vector pulse width, and rapid dynamic response and good steady-state performance are possessed.

The invention provides a single-center projection transformation method of a multi-lens and multi-detector aerial camera. The single-center projection transformation method comprises the following steps: 1) establishing a virtual image space coordinate system with uniform standards; 2) establishing a mathematical model for reflecting a related position relation between multi-lens cameras and a related position relation between a plurality of detectors; 3) solving combined position elements and distortion parameters of a plurality of lenses and the plurality of detectors through static geometric calibration; 4) establishing a mathematical mode for related position changes of images of the plurality of detectors in a dynamic flight process; 5) obtaining identical points of overlapped regions of the images of the plurality of detectors through rapid matching of short-baseline images; 6) establishing a self-calibration error equation according to an identical points coordinate error minimum principle; 7) carrying out a point-by-point method and finishing iterative solution according to a least squares adjustment principle, so as to obtain accurate related position element in the dynamic flight process. The method provided by the invention is universally applicable to generation of equivalent single-center projection virtual images of a multi-lens and multi-detector area array splicing type aerial mapping camera.

The invention discloses a hierarchical clustering method and system based on multistage layered sampling. The method includes: using randomly-sampled initial sample sets as seeds to build layered inquiry strategies, and distributing corresponding sample number to each layer of inquiry strategies on the basis of the estimate variance minimum principle of each layer; using the layered inquiry strategies to perform layered sampling on data sources to obtain the representative sample sets with high sample representativeness; clustering the samples in the representative sample sets, and performing secondary sampling on the data sources on the basis the boundary points of the clusters to obtain uncertainty sample sets with high sample uncertainty; clustering on the basis of the collection of the initial sample sets, representative sample sets and the uncertainty sample sets to estimate the clustering center of the data sources. The method has the advantages that high representativeness and uncertainty of the samples are guaranteed through multistage layered sampling, the problem that randomly-sampled samples are poor in representativeness is solved, and the accuracy of data source clustering is increased.

The invention provides an inverse kinematics solving method for a 6-DOF (degree of freedom) industrial robot. The method comprises the following steps: establishing a connecting rod coordinate system, wherein the connecting rod coordinate system comprises an X-Z axis plane, coordinate systems corresponding to six joints of the industrial robot and a coordinate system of an end effector of the industrial robot; on the basis of the connecting rod coordinate system, calculating an Euler angle transformation matrix according to structure geometric parameters among the six joints of the industrial robot; sequentially solving rotation shaft rotation angles of the six joints of the industrial robot through the Euler angle transformation matrix according to the preset sequence; and according to the eight solving results corresponding to the rotation shaft rotation angles of the six joints, disintegrating the sum of norms of difference values of the joint rotation shaft rotation angles corresponding to previous joint space places, and selecting an optimal solution according to a norm comprehensive minimum principle. The method has the advantages of being high in solving precision, fast in solving speed, easier to understand in the solving process, and small in calculation amount.

The invention discloses a wire single-phase earth fault single-end ranging method using a ranging scale minimum principle. The method includes: measuring fault-phase voltage, fault-phase current and fault-phase negative-sequence current and zero-sequence current at a transmission line protecting mounting position; selecting initial fault distance as 1x which is increased gradually by a step length delta 1, sequentially calculating ranging scale e (1x) of each point in the whole transmission line, and selecting the distance from the point with the smallest ranging scale e(1x) to the transmission line protecting mounting position as fault distance. Physical features of transmission line voltage and current transmission are described through distribution parameters, ranging precision is unaffected by transmission line ground capacitors, and the method is applicable to single-phase earth fault single-end ranging of transmission lines of optional voltage grades, especially applicable to single-phase earth fault single-end ranging for transmission lines with ultrahigh voltage.

The invention provides a non-restraint face identification method based on HOG characteristic sparse representation. According to the method, face database pictures are firstly inputted, and HOG characteristics of the inputted pictures are extracted; multiple pictures of each category of persons are selected for training, and other pictures are for tests; HOG characteristic column vectors of each training picture of each category of persons are utilized to construct a characteristic dictionary; a gradient projection sparse reconstruction algorithm is utilized to acquire HOG characteristic sparse representation coefficients of test samples; the sparse coefficients are sequentially kept according to categories, zero setting of the residual coefficients is carried out to acquire an approximate sparse coefficient, and the approximate sparse coefficient is multiplied by a dictionary to acquire a test sample estimate; a mean square error of the test sample and the estimate is calculated, a category of the test sample is determined according to the mean square error minimum principle. The method is advantaged in that influence of the non-restraint environment on face identification performance is effectively reduced, non-restraint face identification robustness is improved, a problem of slow operation speed caused by large dictionary dimensions existing in a traditional sparse representation classification algorithm is solved, and algorithm operation efficiency is effectively improved.

The invention discloses a method for rapidly extracting the crop planting area and the phenological information in a large range. The method comprises the following steps of S1, selecting the cultivated land sample lattice points, and extracting the LAI time sequence data of each sample lattice point based on a low spatial resolution remote sensing product; S2, carrying out filtering processing onthe LAI time sequence data of the sample lattice points to obtain a filtered LAI characteristic curve; S3, extracting the key phenological periods of the sample lattice points; S4, calculating the root mean square errors (RMSE) of the key phenological periods of the sample grid points extracted by crops in the research area under different filtering methods and the phenological observation valuesof the corresponding agricultural gas stations, and determining an optimal filtering method according to an RMSE minimum principle; and S5, filtering the LAI time sequence data of each cultivated land lattice point in the research area according to the optimal filtering method, extracting the key phenological period of each crop in the whole growth season by utilizing the method in the step S3, and identifying the corresponding planting range and area of each crop according to the key phenological period.

The invention discloses a multi-task mechanical arm posture detecting and error compensating method, and belongs to the technical field of industrial robots. A device used in the method comprises double cameras, a six-joint mechanical arm, an upper computer and a mechanical arm control cabinet. The two cameras are arranged on the two sides of the mechanical arm correspondingly and used for collecting and transmitting image information of the mechanical arm to the upper computer so that posture information of the mechanical arm can be obtained. The six-joint mechanical arm is used for finishing welding, component assembling and goods carrying work. The upper computer is used for conducting image calibrating and processing, task mode selecting and data calculating. The mechanical arm control cabinet is used for receiving instructions of the upper computer and achieving control over the mechanical arm. According to the optimization function minimum principle, the each-step newly-added error compensation amount is calculated, accordingly, the new error compensation amount is obtained, and next movement of the mechanical arm is controlled.

The invention discloses an application of low-thrust control in geostationary satellite orbit inclination maintenance. A simulation procedure includes the steps that an initial satellite status vectorand an estimated thruster work period are input, an objective function and a constraint function are written according to an inclination control objective and an optimal objective, numerical integration calculation is conducted, the optimal thruster work period is solved according to a parameter optimization method, and a post-control objective and an optimal control vector are output. The application is scientific and reasonable, use is safe and convenient, adaptability analysis is conducted through establishment of an inclination maintenance optimized mathematical model based on three methods of the minimum principle, phase plane control and parameter optimization, simulation verification is conducted on the parameter optimization method, a simulation result indicates that a low-thrustcontrol strategy meets an orbit inclination maintenance requirement, the low-thrust control strategy can be used as a reference in following satellite management, and the simulation result indicates that a low-thrust optimization control method is adaptable in geostationary satellite inclination maintenance.

The invention relates to a method for extracting and recognizing facial features. The invention refers to a method for extracting and recognizing a two-dimensional front facial image. The specific recognizing methods are as follows: (1) a method based on a feature face: projecting an original image to a feature space, obtaining a series of dimension-reducing images and taking a main element thereof to express a face; (2) a method based on a neural network: utilizing a system formed by linking a great mass of simple processing units; (3), a method based on a support vector machine: building an ability of precisely studying a specific training sample and correctly recognizing any samples on the basis of vapnik-chervonenkis (VC) dimensional theory of the statistical learning theory and the minimum principle of the structural risk. The method for extracting and recognizing facial features can effectively reduce the error rate of the feature face part analysis by adopting the method based on the feature face; the method based on the neutral network can get good effect by applying to the face detection and the front face recognition; and therefore, the problem of complex mode recognition and action control can be solved.

The invention discloses a power control method. The method includes that a center node of a wireless body area network updates an RSSI (received signal strength indicator) average value symbol 1 currently used for performing power control on a terminal node to obtain an updated RSSI average value symbol 2 according to an RSSI average value Pr of M currently-received consecutive data packets sent by the terminal node, wherein M is greater than or equal to 1; the center node compares the updated RSSI average value symbol 2 with a preset RSSI target value Ptarget to determine whether the terminal node needs to be subjected to power adjustment or not currently; when power adjustment is determined to be needed, the center node selects power adjustment step deltaP used for current power adjustment from a preset power adjustment step set according to that the minimum principles of a formula 1 and a formula 2 are satisfied by guarantee, and the terminal node is triggered to be subjected to power adjustment according to deltaP; the terminal node sends a next data packet by making use of adjusted transmitted power.

The invention belongs to the technical field of computer network safety, and discloses a dynamic window selection method based on the game theory, and a wireless network trust management system. The method comprises the steps: building a game model between a trust management system and an attacker; carrying out the systematic quantification of a strategy set of the attacker, and quantifying a strategy set according to the strategy set of the attacker; obtaining a payment matrix of the game theory through employing numerical simulation, and solving the game model through the maximum-minimum principle; and selecting the size of an optimal window according to a Nash equilibrium point. According to the invention, the method can achieve the dynamic selection of the size of the optimal window inthe trust calculation according to the behavior characteristics of the attacker and a network state, achieves the minimization of system loss, and achieves the detection of a malicious node with thedynamic behaviors.

The invention provides a deviation value control method for cold rolling hot galvanizing coating uniformity. The method comprises the steps of: 1) establishing an influence model of the knife lip opening degree on coating thickness; 2) establishing an influence efficiency function matrix determining the influence weight of each air knife lip servo motor adjustment amount on each coating; 3) solving a motor adjustment amount according to a quadratic error function minimum principle; and 4) considering the actual application features in terms of correcting the quadratic error function, when the galvanizing thickness measured value of a point deviates from most measuring points, in order to avoid the interference of an extreme value on the coating control of other areas, adding a filtering function in an error function, thus finally obtaining a needed air knife lip opening degree. The invention provides a new galvanized layer thickness calculation model suitable for industrial application, introduces the influence efficiency function matrix, enhances the coating uniformity control accuracy, and simultaneously adds the cost function and the filtering function to improve the coating error function accuracy, thereby enhancing the coating uniformity calculation accuracy, and improving the surface quality of a galvanized product.

The invention provides a dynamic updating method of a covariance matrix in cooperative multipoint joint transmission by taking a typical self-adaption codebook method as a basis to reoptimize a design. An equivalent system between the covariance matrix and a codebook is utilized; based on a mean square error minimum principle, and at a receiving end, the corresponding codebook and one parameter are utilized to simulate a difference value between a covariance matrix at the current moment and a covariance matrix at the last moment; and meanwhile, an index and a corresponding parameter of the codebook are fed back to an emission end. At the emission end, the corresponding codebook is searched according to an index number and the covariance matrix at the current moment is reconstructed by utilizing the feedback parameter and the covariance matrix (or an estimated value) at the last moment, so as to realize a dynamic updating process of the covariance matrix.

Aiming at the problem of minimum engine fuel consumption rate of an extended-range electric vehicle, an extended-range power generation system and a generator current change device are controlled to enable the output bus voltage to be stable, so that the actual rotating speed of an engine is changed along with the load change; and the actual rotating speed of the engine follows up the fuel consumption rate minimum principle to control real-time fuel injection quantity of the engine to realize electric energy needed by automatic system output and always minimum fuel consumption rate. The energy is saved; the emission is reduced; and the method is simple and feasible.

The invention relates to a high-efficiency engine and a control method. The high-efficiency engine and the control method aim at the control problem of main shaft rotating speed of an engine when theautomobile engine adopts the engine rotating speed to determine the opening degree of a throttle valve and oil injection according to the principle of minimum fuel consumption rate so as to improve the fuel efficiency of the engine. According to the high-efficiency engine, an oil cylinder is divided into two groups, namely group A and group B, each group is provided with an independent air inlet system, and the air quantity of the B group is controlled by a traditional accelerator pedal mode so as to achieve main shaft rotating speed control; and the group A adopts the rotation speed of the engine to determine the opening degree of a throttle valve and fuel injection quantity according to the minimum principle of the fuel consumption rate, so that the fuel consumption rate of the oil cylinder in the group A is always optimal, and the overall fuel efficiency of the engine is improved.

The invention provides a filter disk and a light filter device in an Archimedes spiral line shape and design methods thereof, belonging to the field of multi-band imaging. The invention provides a filter disk in an Archimedes spiral line shape, wherein a light filter area is marked out on the filter disk according to an Archimedes spiral line marked out at the center of a circle of a disk surface; the invention designs a light filter device in an Archimedes spiral line shape through the application of the filter disk, wherein a detector in a row-by-row read-out manner is allocated; further, the invention provides a design method of the filter disk in an Archimedes spiral line shape, wherein the shape of the Archimedes spiral line is firstly determined according to the size of the detector and the number of light splitting wave bands, and then the semi-diameter of the filter disk is determined according to minimum polar diameter principle and safety factor principle; and the invention also provides a design method of the light filter device in an Archimedes spiral line shape, wherein the concept of synchronous exposure error of the filter disk is provided, and the relative position where the detector is placed is determined by using the minimum principle of synchronous exposure error. According to the filter disk and the light filter device in an Archimedes spiral line shape and the design methods thereof, the light filter efficiency can be improved, and the filter device and the light filter device are suitable for optical light-dividing devices.

The invention discloses a determination method for a shape shifting robot attitude transformation optimal path. According to the determination method for the shape shifting robot attitude transformation optimal path, the graph theory is introduced on the attitude control of a shape lifting robot, an attitude transformation problem is converted into a graph theory related problem, accordingly, according to the attitude transformation complexity weight minimum principle, when the optimal attitude transformation path is obtained, a control system can send a corresponding driving order to a motor of each joint of the shape shifting robot, so that the shape shifting robot can transform the joint turning angles of the shape shifting robot in sequence according to the optimal attitude transformation path, the reasonable sequence transformation of the attitude of the shape shifting robot is achieved, the interconversion between different attitudes is achieved, for different environment conditions, the attitude transformation of the shape shifting robot can be achieved stably, efficiently and reasonably, and therefore the good environmental suitability is achieved.

The invention discloses a downlink precoding method for a multi-user distributed MIMO (Multiple Input Multiple Output) multi-antenna system. The method comprises the following steps of S1: deploying M remote antenna units in a community, wherein each remote antenna unit is connected to a central processing unit through an optical fiber, each remote antenna unit is configured with Nm transmitting antennae, m equals 1, 2, ..., M, K active users exist, each user is configured with Lk receiving antennae, and k equals 1, 2, ..., K; S2: adopting a coordinated multi-point transmission method in the community for the system, combining the remote antenna units for sending data to the users, and selecting the required remote antenna unit from all the remote antenna units according to an average path loss minimum principle by using a selective transmission policy to send the data to the users; and S3: adopting a signal-to-interference and noise ratio criterion-based receiving combination method for receiving the data at a receiving end.

The invention discloses a rapid coordination optimal control method used for the gear shifting process of a multi-gear blade electric vehicle. As for the contradiction of dynamic property and riding comfort index requirement aspects in the gear shifting process, considering saturation constraint of a motor and a clutch execution mechanism, the motor active cooperation issue within the limited gear shifting time is described as the issue of time domain diminishing coordination optimal control over output torque of the motor and a clutch, the necessary condition of an optimal solution is obtained through a minimum principle, the optimal Lagrangian operator is solved through a method of bisection, and accordingly the solution of the optimal control problem is obtained, that is, the optimal control input acts on a motor and transmission system of the blade electric vehicle, and control at the sampling moment is finished; and optimal solution circulation at the new sampling moment is started till the end moment of an inertial phase.