56 results about "Main diagonal" patented technology

The invention relates to the technical field of electrical digital data processing, and discloses a lightweight-based multi-modal data enhancement method, which comprises the following steps: acquiring a multi-modal feature tensor; extracting a vector orthogonal projection scalar and determining the novelty; updating the global covariance matrix when the novelty is greater than a redundancy threshold, and maintaining the global covariance matrix in a register state when the novelty is not greater than the redundancy threshold; extracting a main diagonal variance component to determine a differential modulation coefficient; calculating a second-order moment manifold projection operator according to the global covariance matrix, and calibrating the operator by using a differential modulation coefficient; the calibrated operator is used for carrying out orthogonal projection on random noise to generate a structured disturbance vector, the structured disturbance vector is superposed to a multi-modal feature tensor to output enhanced features, a novelty judgment mechanism is used for restraining statistical deviation caused by steady-state redundant data, computing resource occupation is reduced, and it is ensured that semantic alignment between modals is maintained in enhanced feature distribution.

The invention discloses a method for generating an amplitude preparation circuit and a quantum state preparation method and device, and the method comprises the steps: setting a main diagonal element of a block matrix as a to-be-prepared amplitude, and setting other elements as 0, so that the block matrix is equivalent to a diagonal matrix, thereby facilitating the construction of a unitary matrix through employing the block matrix, and in the unitary matrix, the unitary matrix is not damaged; the to-be-prepared amplitude is arranged at the upper left corner of the unitary matrix, so that the amplitude preparation of the to-be-prepared quantum state can be carried out by utilizing a circuit corresponding to the unitary matrix, and the preparation of the to-be-prepared quantum state by utilizing a large-scale operator can also be understood, thereby being beneficial to more efficiently and accurately preparing the to-be-prepared quantum state.

The invention provides a confusion matrix scoring method and device based on entropy coding, and relates to the technical field of machine learning. The method comprises the following steps: acquiring an original confusion matrix; setting an element in a main diagonal line of the original confusion matrix to be zero to obtain an error matrix; binary entropy coding is carried out on terms of the error matrix in an entropy coding mode, and a coding matrix is obtained; calculating the code length of each code in the coding matrix according to the coding matrix to obtain a code length matrix; multiplying each item of the code length matrix by each item of the error matrix to obtain an average code length matrix; summing each item of the average code length matrix to obtain a total average code length; and the value of the total average code length is used as a scoring index. According to the invention, the error rate and the dispersity of error conditions can be reflected.

A method for compressing a plaintext matrix and a computing device, the plaintext matrix is obtained, the plaintext matrix is a Fourier transform matrix or an inverse Fourier transform matrix, the plaintext matrix is decomposed to obtain a plurality of sparse matrixes, the number of non-zero diagonals of each sparse matrix except a main diagonal is at most 2, and the product of the plurality of sparse matrixes is the plaintext matrix, dividing the plurality of sparse matrixes into n groups, aiming at any group of sparse matrixes, determining a product of the group of sparse matrixes as a combined matrix corresponding to the group of sparse matrixes, aiming at any combined matrix, determining an access period corresponding to the combined matrix, and respectively performing access on the combined matrix along each diagonal line according to the access period, the compression diagonals corresponding to the combined matrix are determined according to the access result, and the plaintext matrix can be compressed by utilizing the repetition rule of the diagonal elements of the combined matrix obtained after the plaintext matrix is decomposed and combined, so that the space required for storing the plaintext matrix can be reduced, and the efficiency of transmitting the plaintext matrix can be improved.

A computer-implemented method is for reducing computing time when determining an inverse matrix from a symmetrical input matrix comprising n rows and n columns. The method includes forming i blocks with mi rows and mi columns, with mi less than n and i being greater than or equal to 2. The i blocks are each formed from entries of main diagonals which are most strongly correlated and mi entries of secondary diagonals in the same rows and columns as the entries of the main diagonals. The method further includes generating a block diagonal matrix from the i blocks, and generating the inverse matrix to the input matrix by inverting the blocks in the block diagonal matrix.

Matrix multiplication operations can be implemented, at least in part, on one or more tensor cores of a parallel processing unit. An efficiency of the matrix multiplication operations can be improved in cases where one of the input operands or the output operand of the matrix multiplication operation is a square matrix having a triangular data pattern. In such cases, the number of computations performed by the tensor cores of the parallel processing unit can be reduced by dropping computations and / or masking out elements of the square matrix input operand on one side of the main diagonal of the square matrix. In other cases where the output operand exhibits the triangular data pattern, computations can be dropped or masked out for the invalid side of the main diagonal of the square matrix. In an embodiment, a library implementing the matrix multiplication operations is provided.

The application discloses a multiple wave prediction method and device, a computing device and a storage medium. The method comprises the following steps: acquiring frequency domain data of any shot point at any seismic trace; generating a seismic data matrix according to the frequency domain data, the seismic data matrix being an upper triangular matrix with a main diagonal line of 0, and any non-first column of the seismic data matrix containing frequency domain data of at least one seismic trace of the same shot point; constructing a multiple wave matrix, the multiple wave matrix being an upper triangular matrix with a main diagonal line of 0, and any non-first column of the multiple wave matrix containing a multiple wave model of at least one seismic trace of the same shot point; establishing a functional relationship between the multiple wave matrix and the seismic data matrix; and obtaining model frequency domain data corresponding to any multiple wave model in the multiple wave matrix according to the functional relationship. According to the scheme, the prediction efficiency of the multiple wave can be improved under the premise of ensuring the prediction accuracy of the multiple wave.

Disclosed is an operation method for executing an addition operation on quantized matrices. This operation method comprises the steps in which: an NPU matrix multiplication unit executes a matrix multiplication operation on a first matrix and a second matrix, wherein the first matrix has a size of R0*2C0 and is obtained by concatenating a first input tensor and a second input tensor, each of which is composed of quantized values and has a size of R0*C0, and the second matrix is obtained by concatenating a first diagonal matrix having a size of C0*C0 and having all main diagonal element values equal to integer N1 and a second diagonal matrix having a size of C0*C0 and having all main diagonal element values equal to integer N2; and an NPU vector processing unit calculates elements of a non-quantized tensor obtainable by adding the second input tensor to the first input tensor, by adding real number B to a product of real number R and a third matrix calculated by the matrix multiplication operation.

The invention provides an internal force calculation method and system for a door-shaped tower multi-nominal-height tower leg component for realizing a digital power grid, and relates to the technical field of digital power grids. According to the method, basic parameter information of the door-shaped tower is firstly obtained, then load influence factors under different non-uniform icing working conditions are considered, and the load design value at the line hanging point of the door-shaped tower is calculated. The load design value is used for solving the main material internal force and the inclined material internal force of the tower leg under each door-shaped tower subtower nominal height combination, and the most unfavorable internal force is determined; based on the most unfavorable internal force of the shortest and longest tower leg main diagonal members, the method further utilizes an interpolation method to calculate the main diagonal member internal force of each tower leg. Based on the method, the requirements of tower legs with different heights can be met, and the design flexibility and adaptability are improved. In addition, the method is beneficial to reducing potential safety hazards caused by improper design, reducing operation risks of a power grid system, promoting digital application of power grid design and promoting the power grid to develop in a more intelligent and safer direction.

The embodiment of the invention provides a multidirectional seismic attribute tensor fusion method and device, equipment and a medium, and relates to the technical field of oil-gas exploration and development. The method comprises the following steps: extracting seismic attribute data volumes in a plurality of observation orientations from five-dimensional seismic data, and respectively calculating a seismic attribute tensor corresponding to the seismic attribute data volume in each observation orientation, each seismic attribute tensor represents the change rate of the gradient of the seismic attribute in the corresponding observation orientation along three orthogonal directions of a three-dimensional space; adding the values of the elements with the same element positions in each seismic attribute tensor to obtain a multi-azimuth seismic attribute tensor fusion operator; and calculating the sum of main diagonal elements in the multidirectional seismic attribute tensor fusion operator to obtain a multidirectional seismic attribute tensor fusion result. Thus, according to the obtained fusion result, the influence of the included angle between the observation coordinate system and the constitutive coordinate system is eliminated, and effective fusion of multi-azimuth seismic attribute information is achieved.

A gridless coherent signal direction-of-arrival estimation method based on alternating projection according to the present invention is characterized in that: the patented method uses a hydrophone array installed on an underwater vehicle to receive signal data to construct a positive semi-definite matrix S0, and uses the projection method to alternately project S0 onto a rank-constrained set and a Toeplitz matrix with averaged main diagonal elements. Secondly, the convergence degree of S0 is judged, and then T i (u) is subjected to reduced-dimensional space smoothing-singular value decomposition. Finally, z is obtained by using the polynomial root-finding method, and the incident angle of the coherent signal is solved by using the corresponding mapping relationship. The patented method effectively realizes the angle estimation of coherent signals. Secondly, the polynomial root-finding method is used instead of spectral peak search, which effectively reduces the computational amount, improves the robustness and real-time performance of the algorithm, and has high estimation accuracy, having important engineering application value.

The present invention relates to the technical field of radar signal, and specifically provides a radar interference identification method, system, terminal and storage medium based on bispectrum phase angle, including: acquiring observation data received by a radar; calculating a bispectrum phase angle matrix of the observation data; converting the bispectrum phase angle matrix into a gray-level co-occurrence matrix, and extracting image texture features based on the gray-level co-occurrence matrix; extracting the numerical values of the main diagonal from the bispectrum phase angle matrix to obtain a diagonal sequence, and performing spectrum analysis and sequence trend feature analysis based on the diagonal sequence; performing principal component analysis based on the image texture features and sequence trend features, and inputting the features after principal component analysis into a preset classification model to obtain the result of identifying a true target or a false target. The present invention improves the reliability of identifying a true target and an interference signal, and solves the problem that it is difficult to distinguish a towed interference signal by traditional methods.

This invention belongs to the field of sparse matrix storage and distributed parallel computing technology. It discloses an adaptive storage and parallel computing method for sparse matrices based on vertex cutting and two-stage compression. The method includes: initializing a cross-linked list in memory for dynamic assembly of sparse matrix elements; reducing the dimensionality of the dynamically assembled cross-linked list data structure to a one-dimensional continuous compressed sparse row format using a two-stage traversal algorithm; constructing a heuristic diagnostic model based on row non-zero variance and diagonal occupancy to achieve adaptive matrix storage; extracting the pure graph topology after removing self-loop elements on the main diagonal of the sparse matrix, and performing multi-way recursive graph segmentation based on vertex cutting on the pure graph topology to generate a distributed mapping array; and constructing a communication scheduling table based on the distributed mapping array to achieve deep overlap between non-blocking data exchange and local matrix computation. This invention significantly improves the storage compression rate and parallel computing scalability of large sparse matrices.

This invention relates to the field of digital signal processing technology, and discloses a DSP multi-core parallel QR decomposition method and apparatus based on tile algorithm. The method includes: dividing the matrix to be decomposed into blocks in the horizontal direction according to the number of cores of the DSP processor and setting tile blocks; performing QR decomposition on the main diagonal tile blocks; and updating all tile blocks to the right of the main diagonal tile blocks in the horizontal direction; pairwise coupling of the main diagonal tile blocks with each tile block in the vertical direction of the same column; performing QR decomposition on the coupling matrix formed by each pair of couplings; and updating all coupling matrices to the right of the pair of coupling matrices in the horizontal direction; and cyclically executing the decomposition and horizontal update of the main diagonal tile blocks, the coupling decomposition of the tile blocks in the same column, and the update of the right coupling matrix until all main diagonal tile blocks in the matrix to be decomposed have been processed, resulting in an upper triangular matrix. This invention can fully utilize the parallel processing advantages of multi-core processors to achieve inter-core parallel data processing.

The invention relates to the technical field of radar signals, and particularly provides a radar interference identification method and system based on a bispectrum phase angle, a terminal and a storage medium, and the method comprises the steps: obtaining observation data received by a radar; calculating a bispectrum phase angle matrix of the observation data; converting the bispectrum phase angle matrix into a gray level co-occurrence matrix, and extracting image texture features based on the gray level co-occurrence matrix; extracting numerical values of main diagonals from the bispectrum phase angle matrix to obtain a diagonal sequence, and performing spectrum analysis and sequence trend characteristic analysis based on the diagonal sequence; and performing principal component analysis based on the image texture features and the sequence trend features, and inputting the features after the principal component analysis into a preset classification model to obtain a result of the identified real target or false target. According to the method, the reliability of identifying the real target and the interference signal is improved, and the problem that the dragging interference signal is difficult to distinguish by a traditional method is solved.

The application discloses a frequency coupling grid-connected inverter stability improvement method, which introduces the q-axis voltage and the q-axis current after the suppression link into the q-axis control in the form of positive feedback as the reference value of the q-axis current through the q-axis voltage loop compensation mode. The strategy can ingeniously utilize the sign difference of the frequency domain convolution itself in the positive sequence and the negative sequence, realize the increase of the amplitude of the main diagonal line subsystem in the admittance matrix of the grid-connected inverter, and greatly reduce the amplitude of the coupling subsystem, so that the coupling subsystem is negligible compared with the main diagonal line subsystem, and the frequency coupling oscillation is essentially suppressed and the stability of the system is improved.

The application discloses a running-in state identification method based on a friction signal threshold-free recursive analysis result, extracts nonlinear components of a friction signal time sequence output in a friction and wear process by collecting the friction signal time sequence; constructs a threshold-free recursive matrix by combining a sliding window and an avoidance embedding phase space reconstruction method and realizes visualization of the threshold-free recursive matrix in a two-dimensional plane; divides a lower triangular matrix of the threshold-free recursive matrix into several regions by a group of equidistant line segments parallel to a main diagonal line of the recursive matrix, extracts mean values of recursive elements in the regions, analyzes a change rate of element values of the threshold-free recursive matrix when the threshold-free recursive matrix transitions along the main diagonal line to edges and corners as a recursive measure, analyzes variation rules of the recursive measure along with a running-in and wear process, and further realizes running-in state online identification driven by the friction signal threshold-free recursive analysis result. The application optimizes a recursive characteristic representation and a measure extraction method of the friction signal time sequence, and realizes running-in state online identification from a perspective of dynamics-friction coupling.

The application discloses a multifunctional radar wave element extraction method and system based on a dot matrix model, and the method comprises the following steps: for a multifunctional radar (MFR) pulse sequence, a dot matrix (D) based on a pulse repetition interval (PRI) value, a pulse width (PW) value and a radio frequency (RF) value is respectively constructed according to the threshold values of the corresponding PRI value, PW value and RF value of the MFR pulse sequence; PRI ,D RF ,D PW ; the constructed dot matrix (D PRI ,D RF ,D PW is respectively subjected to image preprocessing, image hole filling and image closing operation; an L-shaped corner point on a main diagonal line of the preprocessed dot matrix is detected by using a Harris corner point detection operator, that is, a wave element starting point; and a union set of the detection results is obtained, that is, a wave element starting pulse set. The application does not depend on cluster parameter setting, can fully utilize the overall modulation law of the wave element, reduces the false alarm probability while improving the wave element detection probability, and still has good performance in the case that the pulse is lost or the parameter measurement error is large.

A remote sensing image encryption method based on two-dimensional discrete memristor hyperchaotic mapping includes (1) chaotic sequence generation; (2) main diagonal row-column diffusion; (3) pixel position scrambling operation; and (4) sub-diagonal row-column diffusion. This method employs a diffusion-scrambling-diffusion structure, using the obtained chaotic matrix to perform main diagonal row-column diffusion, pixel position scrambling, and sub-diagonal row-column diffusion operations on the plaintext image to obtain the ciphertext image. Experimental results show that this invention can resist differential attacks and brute-force attacks, making it difficult for attackers to obtain effective information from the ciphertext image. It not only has fast and efficient encryption capabilities but also high security performance, successfully ensuring the secure transmission of remote sensing images in the network.

Taking advantage of the strong robustness of the frequency-domain digital watermarking algorithm, the present invention discloses a blind watermarking method for color digital images based on Contourlet transform and Schur decomposition. According to the characteristics of multi-scale, multi-directionality, translational invariance of the Contourlet transform and low complexity of Schur decomposition, the present invention first performs hierarchical processing on the host image and conducts Contourlet transform on the hierarchical image. Then, the selected coefficient blocks are subjected to Schur decomposition to obtain an upper triangular matrix, and the embedding and blind extraction of the color digital watermark are completed by quantifying the first main diagonal element of the upper triangular matrix. The present invention belongs to the technical field of cyberspace security, not only has good watermark concealment, but also has the characteristics of strong robustness and high security, and is suitable for occasions where color image copyright protection is carried out quickly and efficiently.

The invention discloses a goodness vector calculation method for measuring modal filtering performance of a vertical linear array. The goodness vector calculation method comprises the following steps: (1) initializing marine environment parameters, line spectrum signal parameters emitted by a sound source and vertical receiving array parameters; (2) calculating each order normal wave mode function excited by a line spectrum signal emitted by a sound source and a receiving sound pressure value at each hydrophone depth of a vertical array by using a Kraken model, and establishing an array receiving sound pressure vector; (3) constructing a sampling mode function matrix, multiplying a pseudo-inverse matrix of the sampling mode function matrix by the sampling mode function matrix to obtain a mode filtering matrix, and calculating a relative attenuation coefficient of each order mode; (4) calculating to obtain a contribution degree matrix by using the modal filtering matrix and the relative attenuation coefficient of each order of modal, and taking out main diagonal element values of the contribution degree matrix to form a goodness vector; according to the method, the modal filtering performance can be quantitatively represented, and a quantitative analysis means is provided for measuring the modal filtering performance under the vertical linear array.

This invention provides an adaptive detection method, apparatus, and device for ship targets in remote sensing images. The method includes: constructing a main diagonal direction and a secondary diagonal direction strongly correlated with the geometric shape of the ship target based on reference points of the ship target, and generating main diagonal sampling points and secondary diagonal sampling points along these two directions. This allows the feature sampling area to be distributed along the possible slender structure of the ship target, overcoming the diffusion of traditional grid sampling strategies. By using a gating network to dynamically generate fusion weights based on the feature responses of the main diagonal direction and the secondary diagonal direction, the actual tilt direction of the ship's body can be adaptively determined, thereby enabling the aggregated sampling to accurately focus on the ship itself. This effectively solves the technical problem that the distribution of sampling points is difficult to fit the ship's contour when processing slender, tilted ship targets, improving the feature extraction accuracy of ship targets and ensuring the accuracy of ship target detection.

Disclosed is a neural network operation method using an NPU, the method comprising the steps of: inputting, by the NPU of a computing device, a matrix stored in a memory and a transposed matrix of the matrix to a matrix multiplication operator; generating, by the matrix multiplication operator, a first output matrix by performing a matrix multiplication operation on the transposed matrix and the matrix; and storing, by the NPU, main diagonal elements of the first output matrix in the memory as a first reduced array of the matrix. The first reduced array is an array including sums of squares of element values included in each column constituting the matrix.

The invention discloses a directed ring causal structure discrimination and estimation method for network intelligent operation and maintenance, relates to the technical field of network intelligent operation and maintenance, and provides a solution based on high-order cumulant matrix analysis for causal discovery and effect estimation requirements of a feedback loop in a network system. A unified cumulant matrix construction principle is established, so that cumulant total orders of main diagonal elements and auxiliary diagonal elements of the matrix are the same; on the basis, the system firstly utilizes rank conditions of a forward three-order cumulant matrix and a reverse three-order cumulant matrix to realize loop detection; and after the existence of the feedback loop is confirmed, constructing a mixed third-order cumulant matrix, constructing a solvable equation about a causal coefficient by utilizing determinant properties, directly completing loop effect estimation, and realizing integration of loop discrimination and effect estimation. According to the method, a complex intra-ring causal effect estimation problem is converted into an algebraic problem which can be solved directly, and accurate causal support is provided for network performance optimization, resource scheduling and safety protection.

The invention relates to a domestic DCU platform-oriented sparse diagonal matrix vector multiplication optimization method. The method comprises the following steps: firstly, preprocessing original matrix data generated by ship simulation, and finishing initial data structured conversion by adopting a COO format; on the basis of a variable threshold mechanism, matrix elements are divided into a main diagonal dense region and a main diagonal discrete region, and efficient storage is achieved by optimizing index mapping. And further performing secondary division on the main diagonal region by applying a multi-stage compactness evaluation model to generate a high-density part and a sparse part, and performing storage compression by adopting an autonomously designed VHCM mixed compression format. Transmitting the compressed and stored related data array from a host end to an equipment end, and performing DCU parallel SPMV operation in a manner that one thread block processes one sub-block and one thread processes one row; and finally, transmitting a thread operation result from the equipment end to the host end, and creating a result array at the host end to integrate and store the operation result.

The invention relates to the field of shoe soles, in particular to a design method of a bionic shoe sole with propelling performance, which comprises the following steps executed in sequence: S1, constructing a tetragonal insect-like foot lattice unit cell structure, s2, defining design parameters: defining a total deformation coefficient according to the side length of a foot lattice unit cell structure of the insect, the joint diameter of the insect-like structure, a main diagonal deformation coefficient and a secondary diagonal deformation coefficient, and S3, constructing topological structures of different structures according to a preset total deformation coefficient range, obtaining a topological structure database, and determining the design parameters according to the topological structure database. S4, acquiring or calculating the energy absorption efficiency and peak propulsive force of each topological structure in the topological structure database, and constructing a topological structure optimization function, and S5, calculating the optimization function of each topological structure in the topological structure database, selecting the topological structure for filling each region of the shoe sole according to requirements, and acquiring a 3D shoe sole printing scheme; the shoe sole is designed by adopting the insect-like foot dot matrix unit cell structure constructed by the invention, so that the exercise efficiency is improved.

A method for determining and an apparatus for determining the amplitudes of corner reflectors, the method comprising: converting a scattering matrix corresponding to each pulse of radar echoes into a Kennaugh matrix; pulse accumulation of a plurality of pulses to obtain an average Kennaugh matrix; decomposing the average Kennaugh matrix using a Yang decomposition method to obtain a Kennaugh matrix of a corner reflector; converting the Kennaugh matrix of the corner reflector into a coherence matrix, and converting the coherence matrix into a scattering matrix; and determining the amplitudes of odd-order scattering and even-order scattering in the corner reflector based on a main diagonal of the scattering matrix.

The invention provides a dynamic optimization method for strip matrix Cholesky decomposition. The dynamic optimization method comprises the following steps: firstly, generating a partitioning strategy according to hardware characteristics and matrix bandwidth, carrying out iterative computation along a main diagonal, decomposing a current diagonal block and updating in-band related sub-blocks in each iteration, and processing out-of-band data through a working area; secondly, fusing dot product, matrix-vector multiplication and vector scaling operations in diagonal block decomposition into a single kernel function, and dynamically allocating threads according to a current column calculation load; and finally, organizing the decomposition process into a fixed assembly line based on the strategy and the fusion kernel, and scheduling the corresponding kernel to execute along a diagonal sequence according to the block type until the decomposition is completed. The invention further provides a dynamic optimization system for the strip matrix Cholesky decomposition. Therefore, by means of the method, the kernel starting overhead is effectively reduced, the data locality and parallel efficiency are improved, and the calculation performance of strip matrix Cholesky decomposition on a heterogeneous platform is remarkably improved.

This application relates to a building frame reinforcement structure for building construction, comprising multiple mounting brackets for fixed installation on the exterior of the building frame; multiple horizontal frames for fixed installation on the exterior of the building frame are arranged between adjacent mounting brackets, the horizontal frames being arranged at intervals along the length of the mounting brackets; main diagonal braces are arranged at an incline between adjacent horizontal frames, and support members are provided between the horizontal frames and the mounting brackets; one end of each main diagonal brace is provided with a plug-in seat, and the other end of each main diagonal brace is provided with a positioning seat; the plug-in seat is plugged into and fixed to its corresponding support member; multiple sets of plug-in slots are provided on the horizontal frame at intervals, and the positioning seat is plugged into and fixed to its corresponding plug-in slot. This application has the effect of ensuring that the diagonal braces are installed in place, thereby reducing the installation difficulty of the diagonal braces and improving the overall installation efficiency.

The invention discloses a coding method and a storage system, and relates to the technical field of coding, and the coding method comprises the steps: carrying out the coding of a plurality of to-be-coded code words, obtaining a plurality of maximum distance separable codes, enabling the check bits of the maximum distance separable codes to comprise data blocks of system bits, it is ensured that when a storage node corresponding to a system bit fails, a data block of a check bit with a maximum distance and a separable code can be updated through data restoration of the storage node of the check bit and mutual carrying of symmetrical elements on the two sides of a main diagonal line of a permutation matrix; it is ensured that the failure of the storage nodes corresponding to the check bits can be repaired through the data of the storage nodes corresponding to other check bits, the data of the failure nodes can be repaired only by downloading part of data blocks in the k storage nodes in the repairing process, and the data of the failure nodes does not need to be repaired by downloading all the data blocks in the k storage nodes; and the number of data blocks required for repairing is greatly reduced, so that the repairing bandwidth is reduced.