46 results about "K matrix" patented technology

In a method and apparatus for calculating the sampling path of the k-matrix under given boundary conditions for the examination of a subject by means of a magnetic resonance tomography apparatus having a gradient amplifier with appertaining gradient coils, an input-display terminal, a sequence controller and a system computer as well as an analog-to-digital converter, boundary conditions are entered into the sequence controller or into the system computer via the input-display terminal, the sampling path of the k-matrix is calculated taking the boundary conditions into consideration by the sequence controller or the system computer, and the gradient current curves are determined by the sequence controller or the system computer that lead to a sampling along the previously calculated sampling path when applied to the corresponding gradient coils with utilization of the ADC.

The invention relates to a method for online detection of the concentration of electrolyte of an all vanadium redox flow battery. A divalent vanadium V (II) system, a trivalent vanadium V (III) system and a tetravalent vanadium V (IV) system are analyzed by the aid of ultraviolet and visible spectrophotometry, a divalent vanadium V (II) and trivalent vanadium V (III) mixed system and a trivalent vanadium V (III) and tetravalent vanadium V (IV) mixed system are analyzed by the aid of a K matrix method, and a curve equation of the concentration of the vanadium with various valence states and absorbance in the systems is deduced. The concentration of vanadium ions with various valence states in a test sample can be rapidly detected only by substituting absorbance data of the test sample with unknown concentration in the electrolyte of the vanadium battery into the absorbance-concentration curve equation measured and deduced by the method, and accuracy of the method is proved as compared with a national standard method. The method has a huge application prospect in terms of dynamically monitoring valence changes of the electrolyte of the vanadium ions and simultaneously, qualitatively and quantitatively checking the vanadium electrolyte with mixed valence states.

The invention discloses an interactive filtering method for satellite attitude determination, and aims to overcome the defect that constant gyro drifts cannot be estimated by utilizing the optimal-REQUEST algorithm and improve the algorithm applicability. The method comprises the following steps: step 1, acquiring sensor measurement data, including gyroscope data and star sensor data; step 2, building a state space model of a satellite attitude estimation system, as well as building an attitude K matrix; step 3, according to the state space model, the state estimate of the known moment k, and a gyro measurement value, estimating constant gyro drifts at the moment k+1 by utilizing the CKF algorithm and the optimal quaternion at the moment k, and then compensating the gyro measurement value; step 4, according to the compensated gyro measurement value, carrying out time update and measurement update by utilizing the optimal-REQUEST algorithm, so as to obtain the optimal K matrix at the moment k+1; the remaining steps of obtaining the optimal quaternion at the moment k+1. The interactive filtering method is beneficial to improvement of the estimation precision.

A method of registering and modeling a deformable shape in a digitized image is provided, comprising the steps of providing a measurement matrix W of N measurements of P points of a D-dimensional deformable shape, determining a basis number K for the N measurements, wherein K<N, and selecting K measurements of said measurement matrix W as a basis set, decomposing said measurement matrix W into a matrix product Mx∃B, wherein M is a proposed scaled rotation matrix and B is a proposed basis matrix, computing a matrix Q_k defined by $M_i{Q}_k{M}_j^T=\{\begin{array}{c}{I}_{D\times D},i=j=k\\ 0_{D\times D},\left(i,j\right)\in \Phi \end{array},$

where Φ stands for {(i, j)|i=1, . . . , K; j=1, . . . , N, iγk}, which represents an ambiguity matrix transforming the proposed scaled rotation matrix and the proposed basis matrix into a true scaled rotation matrix and a true basis matrix; decomposing the matrix Q_k into g_kg_k^T, for k=1, . . . , K, wherein g_k is a column of a D∃K % D∃K matrix G; and recovering the true scaled rotation matrix from Mx∃G and the true basis matrix from G⁻¹x∃B.

In a method for magnetic resonance imaging, by combined switching of radio-frequency excitation pulses, slice selection gradient pulses, phase-coding gradient pulses and readout gradient pulses, a matrix in the k-space is scanned row-by-row and transformed using a Fourier transformation into a matrix in the spatial domain, with the polarity of the slice selection gradient being inverted during the scanning of the k-matrix, allowing elimination of the ambiguity artifact.

In a method and apparatus for accelerated spiral-coded imaging in magnetic resonance tomography using spiral-shaped k-space sampling, the underlying k-matrix is under-sampled such that an additional spiral is obtained by point mirroring of the measured values at the center of the k-matrix. This additional spiral forms a complete data set of the k-matrix together with the first spiral for imaging the output information.

The invention discloses an image matching method based on a Zernike matrix. The method comprises the following steps: S1, establishing N layers of template pyramid images; S2, calculating K matrixes of each layer of template images in the N layers of template pyramid images, and establishing an RCS table; S3, establishing N layers of object pyramid images; S4, calculating K matrixes of each object sub-image of the L-th layer of the N layers of the object pyramid images through searching the RCS table; S5, calculating correlation coefficients of K matrixes of the L-th layer of the template pyramid images and the sub-image of each object pyramid image in the L-th layer, and obtaining a matching point position (x<L>,y<L>) of the L-th layer of the object pyramid images; and S6, determining whether L is equal to 1, if so, entering S8, and if not, L=L-1, and entering S7; S7, calculating K matrixes of each object sub-image in the L-th layer within a scope of N<L>*N<L> by taking a point with the coordinates (2 x<L>,2y<L>) as a center in the L-th layer, and returning to S5; S8, calculating the correlation coefficients within a scope of N<Buttom>*N<Buttom> by taking a matching point with the coordinates (x<Buttom>,y<Buttom>) in the first layer as a center point, and obtaining a sub-pixel matching position with the coordinates (x_{,y); and S9, at the sub-pixel matching position with the coordinates (x,y), according to phase, calculating an image rotation angle alpha<^>.}

The soil-water coupled analysis program of the invention computes a global L matrix and a modified global L matrix regarding a volume change rate of a soil skeleton over time, a global H matrix regarding a water permeability of soil, a global M matrix regarding a mass, and a global K matrix regarding a tangent stiffness of the soil skeleton, based on input settings of soils, such as clay, intermediate soil, and sand, to respective elements of a soil foundation, input settings of a solid soil model, and input settings of analysis conditions (steps S140 to S165). The soil-water coupled analysis program formulates a global tangent stiffness equation (simultaneous linear equations) using all these computed matrixes and determines an unknown ‘jerk field’ and a ‘pore water pressure field’ under given boundary conditions, for example, a given deformation condition and a given stress rate condition (step S170). This enables highly-accurate dynamic and static analyses in soil foundations of various soils from sand to intermediate soils and clay.

The invention discloses a method for constructing quasi-cyclic low-density check codes based on Euclidean geometry (EG). The method comprises the following steps of: I, selecting Euclidean geometry EG (m, ps) to construct K sparse matrixes; II, constructing a matrix H by taking K matrixes as sub-matrixes; III, constructing a sub-array H (gamma, rho) of an array H for given code parameters: rho is more than or equal to row weight 1 and less than or equal to K, and gamma is more than or equal to line weight 1 and less than or equal to ps; IV, performing random arrangement to obtain a sparse matrix, wherein T is less than an optional threshold (gamma !) (pho-1) and more than or equal to 104, performing random arrangement for T times to obtain T sparse matrixes, and calculating the quantity of loops 6 in a corresponding Tenna figure; and V, selecting a matrix of which the quantity of loops 6 is smallest for serving as a check matrix of LDPC (Low Density Parity Check) codes to finish the construction of codes. The obtained LDPC codes are (2550, 1553), (5100, 4103), (15345, 11286). In the method, QC-LDPC (Quasi-Cyclic-Low Density Parity Check) codes not containing loops 4 are constructed by using the structural characteristics of EG, and QC-LDPC codes with least loops 6, superior loop distribution and excellent error correcting performance can be selected; and the method is suitable for China digital sound broadcasting.

The invention discloses a nonlinear damage compensation method based on a VOLTERRA model in an OFDM-PON (orthogonal frequency division multiplexing-passive optical network) system. The method comprises the steps as follows: (1), similar sequences are stored to a database from a transmitting terminal and a receiving terminal; (2), information containing a pilot frequency sequence is transmitted and extracted at the receiving terminal; (3), a K matrix is established according to model characteristics; (4), a VOLTERRA model matrix form is established; (5), an initial value of an identification vector is resolved; (6), a constellation diagram is analyzed to establish a difference factor vector; and (7), a new weight vector is established continuously. With the adoption of the method, various types of nonlinear damage in the OFDM-PON system are identified according to the VOLTERRA model, the resolving complexity is reduced by adopting QR for decomposing matrix dimension, self-adaptive correction processing is performed on identification coefficient vectors, and nonlinear interference resistance and reliability of the system are improved.

In a method and apparatus for accelerated spiral-coded imaging (scanning k-space with a spiral trajectory) in magnetic resonance tomography, the user-defined sequence forming the basis of the spiral scanning is modified such that the k-matrix forming the basis of the sequence is scanned only in a sub-region, the sub-region being defined by a symmetrical shortening on both sides of the k-space matrix in a first direction as well as by a one-sided shortening of the k-space matrix in a second direction orthogonal to the first direction.

The embodiment of the invention provides a data processing method, device and system and a computer readable storage medium. The method comprises the steps that: a system parameter, a second matrix and a second encryption parameter are obtained, a matrix set composed of a k * k matrix composed of elements on a polynomial ring is determined, and a k-dimensional vector is composed of elements of which coefficients are valued according to binomial distribution in the polynomial ring; a secret vector and a noise vector are randomly selected from the k-dimensional vector, a first matrix is randomly selected from the matrix set, a first public key is generated according to the secret vector, the noise vector, the first matrix, the second matrix, the second encryption parameter, a target to-be-transmitted data identifier and the system parameter, and the secret vector is taken as a private key; the first public key is sent to a sending end, so that the sending end generates a second public key, and to-be-transmitted data is encrypted by using a lattice-based public key encryption algorithm and the public key; and the ciphertext corresponding to the target to-be-transmitted data identifier is decrypted by using an decryption algorithm and the private key, so that the security of accidental transmission of the data is improved.