177 results about "Equivalent transformation" patented technology

The invention discloses an unmanned aerial vehicle (UAV)-unmanned ground vehicle (UGV) combined formation cooperative control method, comprising the following steps: step 1, establishing nonlinear dynamical models of unmanned vehicles in UAV-UGV combined formation; step 2, processing the nonlinear dynamical models of a UAV and a UGV via equivalent transformation, and taking acceleration as a common control target quantity, obtaining a unified control model taking acceleration as a control input in the combined formation; step 3, establishing a ground-air combined formation structure based on a virtual pilot to obtain a stable control signal for the UAV-UGV combined formation and obtain an error model of the combined formation, wherein the control signal is acceleration obtained in step 2 as a common control target quantity; and step 4, designing a UAV-UGV combined formation controller by adopting a RBF (Radial Basis Function) network algorithm according to the control model, the error model and the acceleration serving as a control signal and a control target quantity at the same time, so that the combined formation is stable and reliable.

The present invention discloses face/iris combination optical imaging device. It contains visible light imaging light path system, near infrared light imaging light path system, face imaging light path system; said face/iris combination optical imaging device including above-mentioned imaging light path systematical optical equivalent transformation. The present invention also provides face/iris combination optical imaging method, which contains eye position tracking and positioning, and obtaining maximum quality iris texture image. Said invented device and method can rapid obtain maximum quality iris texture image, and easy to use.

The invention relates to a detection method for codes plagiarism, which collects the similar values of two codes to be detected on different aspects as the input vector of an NN and obtains a conclusion whether plagiarism exists according to the study of the NN. The detection method can eliminate the effects of the codes on the two aspects of distribution and grammar equivalent transformation, can identify the plagiarism means on the aspect of semantic analysis as possible and improve the detection tool of the original detection tool. The detection method has a high detection precision and a good effect, can detect more plagiarism means and is suitable to be popularized.

The invention discloses a neural network inversion control method for a flexible manipulator system. The neural network inversion control method comprises the following steps of establishing a dynamic model of a flexible manipulator servo system and performing equivalent transformation on the dynamic model, and initializing a system state, sampling time and a control parameter; introducing a virtual control variable into the design of each step by combining sliding-mode control and an inversion method, and finally deducing self-adapting controller input; calculating the tracking error, the integral sliding mode surface, the error variable and the differential of a control system. Meanwhile, by utilizing the approximation characteristic of a neural network, the complexity explosion problem brought by the inversion method and the approximation of model parameter uncertainty are avoided; the invention provides the neural network inversion control method capable of effectively improving the location tracking control performance of the flexible manipulator servo system, therefore the stable and rapid tracking of the system is realized.

The invention belongs to the field of power quality managing, and discloses a method for applying the partial least squares regression to power distribution network harmonic source positioning and detecting. According to a model for carrying out equivalent transformation on the electrical power system side and the distortion user side and a harmonic voltage and a harmonic current signal which are obtained through synchronous measurement at the common coupling joint, a regression coefficient is dissolved through the partial least squares regression algorithm, an aggregative variable with the best explanatory capability for a dependent variable is extracted in the manner of decomposing and screening data information in the system, and information and noise in the system are identified. The method integrates the basic functions of multiple linear regression, the canonical correlation analysis and the principal component analysis, the modeling predicting type data analysis method and non-model type data recognition are organically combined, regression modeling, data structure simplifying and variable correlation analyzing can be achieved at the same time, and the method can be widely applied to power quality analyzing, monitoring, evaluating and controlling fields.

The invention relates to a high-precision magnetic resonance and transient electromagnetic spatial constraint joint inversion method. The joint inversion method is based on a forward modeling method combining a continued fraction expansion numerical integration equivalent transformation method and a digital filtering method. The magnetic field calculation precision and speed are both taken into account, an original model and a simplest model are provided, a rotary coefficient matrix equation is designed, and exciting field distribution is simulated and detected when different slope dip angles appear and profile angles change. According to a forward modeling result obtained under the condition of changed dip angle parameters, the forward modeling result is combined with a hierarchical full collection data inversion method, a joint inversion objective function, an iterative equation and a three-dimensional ground model are constructed, a prior information constraint matrix, a roughness matrix, a layer thickness constraint matrix and other spatial constraint matrices are introduced to construct an inversion iterative equation set, based on a large scale matrix of a preconditioning conjugate gradient method, smooth and continuous constraint for the specific resistance, the layer thickness, the water content and the relaxation time is achieved, the problem of inversion non-uniqueness is solved, and the problem that optimization and calculation of a large-scale matrix for spatial constraint inversion involves mass data is solved.

The invention discloses a Chinese reading competence assessment method and system. The assessment method adopts a unified level reading competence assessment standard and mode, so that the problem oflarge competence estimation difference due to large difference of assessment standards is no longer the case; the method also adopts a Chinese language system and culture to realize corpus construction and question compiling, and is suitable for a domestic Chinese reading and evaluation system; through cooperation of an item response theory and equivalent transformation, measuring scale unification of all questions is realized, thereby solving the difference problem of comparison of capability values under different measuring scales, and improving flexibility of assessment groups; through computer adaptive assessment technology, competence assessment and section of scoring questions are realized, thereby greatly reducing the amount of questions required for obtaining reliable competence assessment, and meanwhile, greatly accelerating the score reporting process; and through multistage competence assessment, only reading competence of a test object is estimated, and larger application value is realized in the reading competence improving aspect. The assessment system realizes the same effects above.

The invention provides a thermo-acoustic process testing system and a thermo-acoustic process testing method. The testing system comprises an acoustic field modulation unit, a flow field measurement window, a temperature field measurement window, a micro-scale particle imaging speedometer, a thermal infrared imager and a time-space image mapping and superposing unit. The testing method comprises the following steps of: 1) generating temperature fields, and acoustic fields with stable frequencies, amplitudes and phase angles at the two ends of a thermo-acoustic core; 2) measuring flow field distribution in the thermo-acoustic core at a series of sampling time points tc; 3) measuring a temperature field distribution process along with time variation in the thermo-acoustic core; 4) equivalently converting the flow field distribution at each sample time point tc into the flow field distribution at a virtual sampling time point tc' in the same period T of an acoustic field according to a sampling time point serial number; and 5) acquiring the correspondence between the flow field distribution and the temperature field distribution along with time variation. By the system and the method, the temperature fields and the acoustic fields in the thermo-acoustic core can be synchronously measured, and a measurement result really reflects an actual thermo-acoustic process.

The invention discloses a distribution network fault line selection method based on a random matrix and a Hausdorff distance. Three-phase current sampling values of a feeder line before and after fault are selected, through blocking and translation processing, white Gaussian noise is added, a state data matrix is generated, a product matrix is obtained by using equivalent transformation of singular values of the random matrix, a standard matrix product is obtained by normalization, eigenvalue vectors are acquired, probability statistics is carried out, eigenvalue vectors with the probabilitiesP to be smaller than 10% are used as outliers to be filtered, a Hausdorff distance algorithm is adopted, the Hausdorff distances between the eigenvalue vector of a certain feeder line and the eigenvalue vectors of other feeder lines are calculated, the maximum value is removed, averaging is carried out to obtain an average Hausdorff distance of the feeder line, if the average distance is larger than a threshold, fault of the feeder line is judged, and if the average Hausdorff distance of each feeder line is smaller than the threshold, fault of a connected bus is judged. A fault feeder line and a fault bus can be judged accurately, the judgment does not rely on a distribution network model and is not influenced by a fault location, transition resistance, an initial phase angle and a line type, and the practicability is good.

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

The invention provides a simulation platform based on the IEEE802.1X secure protocol of EAP as well as a method thereof, wherein, a wireless_lan_mac module in the original wireless node of OPNET is improved, and extended authentication modules are added including an EAP authentication module and a port control module, and the added parts and the wireless_lan_mac module are converged to add the function of security authentication successfully. The EAP authentication module is provided with an authenticator and an applicant communicating mutually to complete the security authentication, so the authentication process is presented completely, meanwhile, the complexity is not high and the simulation efficiency is rather good. The port control module is acquired through the equivalent transformation by a finite state machine of IEEE802.1X, the design correctness of a protocol model state machine is ensured, and the disorder among model versions is avoided. The invention realizes the simulation scene for roaming and re-authentication in different BSS of the wireless node, and solves the authentication problem of roaming access. The invention can ensure the integrity, non-repudiation and confidentiality of WLAN data, and can test other various realized wireless secure protocols and multimode access among various protocols on that basis.

The invention discloses a generalized-point-set matching method based on distances from points to lines and the method is capable of realizing rapid and precise matching of point sets. Generalized point sets (p1, p2...pm) and (q1, q2...qn) are extracted respectively from a reference image and a target image, wherein the point sets are discrete and have directivity; when points corresponding to the generalized points sets are searched for, according to an index serial number and searching radius of a reference point, an index serial number of a target point in an adjacent domain of the reference point is determined for rapid query of a target point set; and at the same time, a variable-adjacent-domain nearest-point-searching method is combined and an angle threshold and a distance threshold are adopted to establish rapidly a corresponding relation between directed points; and then according to a point-line distance and point-point distance equivalent transformation method, transformation of a non-linear optimization problem and a linear optimization problem is realized so that a least square method is used to obtain a matching parameter and thus rapid and precise matching is realized and calculation efficiency is improved.

The invention discloses an internal-model-based sliding mode control method capable of inhibiting mismatching disturbance of a permanent magnet linear motor. The internal-model-based sliding mode control method includes the steps that a five-phase fault-tolerant permanent magnet cylindrical linear motor model with mismatching disturbance is set up; an internal model controller of an ideal system is designed by adopting an internal model control strategy; based on the motor second-order mathematic model, mismatching disturbance observers are designed to observe mismatching disturbance of a motor system; two kinds of mismatching-disturbance-based observers are designed, the sliding mode control rules (the symbol is shown in the description) of the system under the two methods are solved; the expression (the symbol is shown in the description) is equivalently transformed to contain system mismatching disturbance errors, the Lyapunov function is selected, and the obtained sliding mode control rules (the symbol is shown in the description), a d-axis voltage set value (the symbol is shown in the description), an x-axis voltage set value (the symbol is shown in the description) and a y-axis voltage set value (the symbol is shown in the description) are used for achieving high-performance operation of the internal-model-based sliding mode control system capable of inhibiting mismatching disturbance of the fault-tolerant permanent magnet cylindrical linear motor by means of a voltage source inverter through a CPWM modulation method, wherein the d-axis voltage set value, the x-axis voltage set value and the y-axis voltage set value are output by a PI current regulator.

The invention discloses an interference suppression method and device. The interference suppression method and device are used for solving the problem that a PMI cannot be precisely estimated and consequently an SLIC receiver or an ML receiver cannot be used for interference suppression. The method includes the steps of obtaining channel parameters which comprise a first channel matrix corresponding to a serving cell and a second channel matrix corresponding to an interfering cell; carrying out equivalent transformation on received signals to obtain an equation (please see the equation in the specification), wherein y stands for the received signals, x0 stands for first transmitted signals sent by the serving cell, xI stands for second transmitted signals sent by the interfering cell, n stands for noise signals, H0 stands for the product of pre-coding matrixes corresponding to the first channel matrix and the serving cell, HI stands for the second channel matrix, and PI stands for a pre-coding matrix corresponding to the interfering cell; making the product of the PI and the xI serve as an equivalent transmitted signal and conducting demodulation on the received signals after equivalent transformation to eliminate interference of the equivalent transmitted signal on the premise that the coefficient of the pre-coding matrix corresponding to the interfering cell is not obtained.

The invention discloses a nonlinear model transformation method of a track loop based on an observation compensation technology, and belongs to the technical field of navigation guidance and control of an unmanned aerial vehicle. A fixed-wing UAV track circuit motion model is decomposed into track declination and track dip motion model, a track velocity motion model and a lateral position and vertical position motion models, through introduction of an intermediate virtual control quantity and the equivalent transformation of the equation, items which are linearly independent of the virtual control quantity at the right end of the whole differential equation is regarded as the total interference to obtain the affine nonlinear form of the track loop motion model, the estimation of each trackmotion state and the total disturbance of the model based on the observation compensation technology of the linear extended state observer and perform compensation when the a track loop controller isdesigned. The method achieves model affine processing, the physical meaning of the processing process is clear, the parameter setting is convenient, and the engineering is easy to implement.

A single/double-circuit power-transmission-line whole-line high-precision fault range finding method is disclosed. Range finding precision of many existing range finding schemes of a general long-distance power transmission line middle section fault is not easy to control because the fault is far away from a measurement apparatus and there are a plurality of range finding influence factors. In the invention, through listing a two-end calculation voltage amplitude ratio under a fault line equivalence network, a proportion function of a distance from a fault point to a line end in a whole length of the line is derived so as to realize accurate range finding to the power transmission line fault. In addition, in order to widen an application scope of the fault range finding method, through considering electrical characteristic differences of a double-circuit line and a single-circuit line, according to a network structure characteristic of a double-circuit power transmission line, and from an aspect of equivalent transformation, a terminal voltage amplitude comparison range finding method adapting to the double-circuit power transmission line is provided. By using the method, range finding operation is simple; a range finding result is not influenced by a transition impedance; a whole line range finding precision is high and a suitable scope is wide. A problem that power transmission line middle section range finding precision is poor can be well solved.

The invention provides a redundancy mechanical arm repetitive motion planning method for suppressing periodic noise. The redundancy mechanical arm repetitive motion planning method includes the following steps that (1), inverse kinematics of a mechanical arm on an angular acceleration layer is analyzed by using quadratic optimization, minimum performance indexes can be a angular velocity norm anda torque norm, and a jacobian equation is constrained by angular acceleration with an angular velocity and a position feedback; (2), equivalent transformation of an angular velocity index and an angular acceleration index is carried out, and quadratic optimization of the step (1) is transformed into standard quadratic programming; (3), standard quadratic programming of the step (2) is solved through a network solver by using a periodic rhythm neural network; and (4), a solving result of the step (3) drives the mechanical arm to move. According to the redundancy mechanical arm repetitive motionplanning method for suppressing the periodic noise, repetitive motion planning of controlling redundancy manipulator is realized by using the periodic rhythm neural network based on quadratic programming, interference of the periodic noise is effectively prevented, the actual track of the manipulator coincides with the desired path, and repetitive motion planning of the manipulator can be achieved.

The invention provides a steady direction of arrival estimation method based on a sparse representation and covariance fitting. The steady direction of arrival estimation method based on the sparse representation and the covariance fitting mainly comprises the steps that a sparse spatial spectrum representation model is established according to antenna array receipt signals, a parameterization representation is carried out on model errors, and an optimization problem is established according to a covariance fitting criterion. The obtained problem is non convex optimization, therefore, the transformation and solution of the problem can be performed through equivalent transformation, parameter increase and step-by-step solution. Without considering the model errors at first, an original problem can be simplified as a convex optimization problem. The convex optimization problem is quickly solved by an existing method, and an initial solution is obtained. Iteration solving is carried out on the original problem, a model error parameter is estimated and an initial estimation is renewed. The steady direction of arrival estimation method based on the sparse representation and the covariance fitting can obtain a precise DOA estimation by low complexity.

The invention discloses an LDPC code quadratic programming decoding method based on degree decomposition and an alternating multiplier method. The LDPC code quadratic programming decoding method mainly solves the problems of slow decoding speed in the existing LDPC code mathematical programming decoding and error floors existing in information transmission decoding. The implementation scheme of the LDPC code quadratic programming decoding method comprises steps of: firstly, performing equivalent transformation on maximum likelihood decoding of an LDPC code into a linear integer programming model based on a decomposition verification equation; secondly, adding a penalty term to an objective function of linear integer programming, and slacking the equivalent linear integer programming modelinto a secondary programming model; and establishing an augmented Lagrange function according to the secondary programming model, and carrying out iterative solution on the augmented Lagrange functionby adopting an alternating direction multiplier method to obtain decoded codes. Compared with the existing decoding method based on mathematical programming, the LDPC code quadratic programming decoding method improves the decoding efficiency. Compared with the traditional BP decoding, the LDPC code quadratic programming decoding method reduces the error floors, and can be applied to magnetic storage, optical fiber communication and satellite digital video.

The invention discloses a power allocation method of a cognitive decode-and-forward relay system, and belongs to the technical field of wireless communication. The actual situation that channel state information between a secondary user and a primary user is difficult to accurately acquire is considered, and the interference power constraint conditions of a secondary user transmitter on the primary user determined according to statistical information between the secondary user and the primary user under the condition that the channel state is unknown and the interference power constraint conditions of a relay on the primary user determined according to statistical information between the relay and the primary user are introduced in the process of optimizing the power allocation scheme in the cognitive decode-and-forward relay system. Firstly equivalent transformation of statistics of the interference constraint conditions is performed and then an original optimization problem is converted into an equivalent convex optimization problem by introducing variables. With application of the method, relatively high system energy efficiency can be acquired under the condition of guaranteeing communication quality of the primary user.

The invention discloses a measuring method for mud-rock flow's impact force which adopts a concrete reinforcement structure contact fiber grating mud-rock flow monitoring device. In this method, first, the maximal arm (Lmax) of impact force is determined. Second, by experiments, a fitting equation F= f(Epsilon) is established between the impact force and the strain of aprimary strain fiber grating sensor under the maximal arm(Lmax) of impact force . The strain characteristics of the strain fiber grating sensor under an arbitrary impact force (FX)are determined again to further determine the arm (Lim) of impact force. Through lever arm equivalent transformation, the arbitrary impact force (FX) and the strain value Epsiloneq of the primary strain fiber grating sensor under the maximal arm (Lmax) of impact force can be obtained. Finally, the value of impact force FX can be solved through the fitting equation. According to the invention, the principle of the method is reliable; the computing process is scientific and convenient; the impact force of a highly disruptive mud-rock flow can be measured; and the magnitude of damage energy of the mud-rock flow to channels and houses can be reflected directly. The method is practicably suitable for field use and can be widely applied.

The invention belongs to the technical field of integrated circuits of data converters, and particularly relates to an input feedforward type Delta-Sigma modulator. The modulator comprises a system level part and a circuit level part, wherein in the system level part, the traditional modulator is used as a prototype of the modulator, and semi-cycle delay is separated from a loop filter through equivalent transformation and transferred to a direct input path and a feedback path, so that the semi-cycle delay on the direct input path shares a clock phase with feedforward simulation summation, quantization and dynamic element matching of a feedback loop, and sequence constraints are further loosened; in the circuit level part, an input network is established by a first integrator of the loop filter through an advance sampling capacitor, a re-sampling capacitor and switches, input signal sampling and the semi-cycle delay are achieved through voltage-doubling sampling / charge redistribution, and feedback is carried out through the re-sampling capacitor so that the feedback path is kept unchanged and quantizing noise is prevented from being folded. The modulator provided by the invention has the advantage that analog-digital conversion with low power consumption and high accuracy can be achieved.

The invention discloses a calculation method for harmonic current of a direct-current side of a hybrid bipolar direct-current transmission system. The calculation method includes the steps: (1) performing equivalent transformation to obtain an equivalent three-pulse voltage source corresponding to an LCC (line-commutated converter) and an equivalent passive circuit corresponding to an MMC (modular multilevel converter); (2) sectioning a direct-current transmission line and a ground wire thereof, and calculating an admittance matrix of each subsection to obtain an admittance matrix of the whole direct-current transmission line by a recurrence method; (3) building a systemic direct-current network according to the equivalent three-pulse voltage source, the equivalent passive circuit and the direct-current transmission line to obtain node voltage of the front end and the tail end of the direct-current transmission line according to the admittance matrixes; (4) acquiring node voltage of each subsection node of the direct-current transmission line by an inverse method according to the node voltage to obtain the harmonic current of the direct-current side. Calculation efficiency of a direct-current loop is remarkably improved on the premise of ensuring effectiveness.

The invention discloses a hardware implementation method for a floating-point type multi-view naked-eye three-dimensional synthetic image, and belongs to the field of 3D (three-dimensional) display. Firstly, equivalent transformation is performed for a pixel synthesis formula, original floating-point type variable complementation is transformed into constant complementation, and further constant complementation is transformed into arithmetic easily implemented by hardware by a comparator. Complexity of floating-point type multi-view naked-eye 3D image synthesis hardware is decreased, variable complementation not easily implemented by the hardware is transformed into arithmetic, and arithmetic speed is increased on the basis of ensuring calculation result accuracy. By changing corresponding parameters, the hardware implementation method is applicable to different types of grating or cylindrical lens structures, and compatible with integer and floating-point type parallax image synthesis methods.

The invention belongs to the technical field of wireless communication, and relates to a low-complexity detection method for an MIMO-SCMA system. The method mainly comprises the following steps: (1) carrying out ZF or MMSE detection on a received signal, and carrying out MPA detection on data of multiple users on antennas to get an initial solution; (2) converting a mathematical model of an MIMO-SCMA system into a mathematical model of an MIMO system through linear equivalent transformation; (3) if the ML value of the initial solution is less than a threshold value, directly outputting the initial solution; and (4) if the initial solution does not satisfy the threshold value, searching for neighboring solutions of the initial solution, and taking the first m optimal neighboring solutions as m initial solutions; and searching for neighboring solutions of the m solutions at the same time, retaining n optimal neighboring solutions for each current solution, retaining the first m different optimal solutions in m*n neighboring solutions as current solutions of next iteration, and carrying out cyclic iterative search until the termination condition is satisfied. The beneficial effect is that the method has obvious advantage in bit error rate performance, and has the advantage of low complexity.