32 results about "Diffusion matrix" patented technology

The invention discloses a time-space adaptive processing method based on radar amplitude and Doppler frequency estimation. The approach is as follows: determining an airborne radar which emits pulse signals and receives radar echo signals in a detection scope, obtaining an N*M*L-dimensional radar echo signal matrix through calculation, calculating a D*L-dimensional radar echo signal matrix P of power values at D Doppler channels corresponding to L distance units in N array elements, obtaining K targets, accordingly, obtaining a diffusion distance unit scope corresponding to power spectra of the K targets, initializing K, calculating an M*delta1k*C-dimensional radar echo signal estimation matrix Tk corresponding to delta1K diffusion distance units in a diffusion matrix unit diffusion scope Lk of the power spectrum of the k-th target, accordingly, calculating a power spectrum diffusion estimation matrix Tk<^> of the k-th target, adding one to k until the power spectrum diffusion estimation matrix Tk<^> of the k-th target is obtained, and then according to a scope from the obtained power spectrum diffusion estimation matrix T1<^> of the first target to the power spectrum diffusion estimation matrix Tk<^> of the k-th target, calculating a training sample F for time-space adaptive processing of the airborne radar.

The invention provides an SAR image super-resolution method based on marginal information and deconvolution. The method achieves the aim that a low-resolution SAR image is reconstructed to be a high-resolution SAR image, and comprises the steps that the low-resolution SAR image is generated to be a result image on which super resolution is to be conducted; original SAR image pixel dot interlace evaluation is conducted; for each image pixel which is not evaluated, four image pixels are used for estimating the gray level distance, and calculating a standard deviation at the same time; the obtained gray level distance and the standard deviation are used for conducting estimation filling on the pixels which are not evaluated; the result image anticlockwise rotates by 45 degrees, and in the same way, the gray level distance is estimated, the standard deviation is calculated, and estimation filling is conducted on the pixels; then the result image anticlockwise rotates by 45 degrees, Gaussian point diffusion matrix deconvolution is conduced on the result image, and the super-resolution result image is obtained after Fourier transform is conducted on the image. According to the SAR image super-resolution method based on marginal information and deconvolution, marginal maximum a posteriori estimation is achieved, the integrality of the image content structure is ensured, fast Fourier transform deconvolution processing is adopted, and the blur caused by marginal interpolation is lowered.

A method of encrypting messages in clear with the aid of a secret key, the method of encryption implementing at least one substitution layer using a substitution table and a diffusion layer using a diffusion matrix, the substitution layer and/or the diffusion layer being configured in a dynamic manner by a control parameter obtained by combining the secret key with the output word from a counter and by performing a non-invertible transformation on the combination. The counter is incremented at least once between two successive plaintext messages. The configuration of the substitution layer is manifested by an identical permutation of bits of each element of the substitution table and the configuration of the diffusion layer is manifested by a permutation of the elements of the diffusion matrix.

The invention discloses a safety risk point identifying method for an integrated traffic transportation network, and the method comprises the following steps: 1), analyzing the correlation of the infrastructures of the integrated traffic transportation network; 2), determining an evaluation index for an event influence result; 3), determining an event influence diffusion matrix; 4), estimating therisk of the infrastructures of the integrated traffic transportation network; 5), determining a safety risk point of the integrated traffic transportation network. The invention aims at solving a problem of an existing integrated traffic transportation network for advanced prevention and control, and innovatively proposes the safety risk point identifying method for the integrated traffic transportation network. The method meets the demands of an integrated traffic transportation manager for the safety risk prevention and control, improves the natural disaster and emergency handling capability of the integrated traffic transportation network, improves the reliability of a traffic transportation system, and lays a foundation for the guaranteeing of the national transportation safety.

The embodiment of the invention provides a digital image encryption method and apparatus based on fractional order transformation, and belongs to the technical field of digital image encryption. The digital image encryption method based on fractional order transformation includes the steps: acquiring the gray value of each pixel of an original image and the image matrix corresponding to the original image; according to the image matrix corresponding to the original image and a preset first scrambling algorithm, determining a spatial domain scrambling image matrix; presetting first fractional order transformation for the spatial domain scrambling image matrix, and obtaining a transformation domain image matrix; according to the transformation domain image matrix, the line number value and the row number value of the image matrix corresponding to the original image, the gray value of each pixel and a preset first diffusion algorithm, determining a diffusion matrix; and according to the diffusion matrix, the transformation domain image matrix and the preset first scrambling algorithm, determining an encryption image matrix. The digital image encryption method based on fractional ordertransformation can improve the anti-noise and anti-loss performance of the cryptograph image during the practical transmission process, and can reduce the bandwidth cost generated during the image transmission process.

The invention provides an image saliency detection method and terminal based on multi-feature diffusion. When a seed node is selected, not all nodes at the edge of an image are defaulted to backgroundnodes. On the whole, three priori algorithms of background priori, color prior and position prior are fused as the high-level prior features of the image to select the seed node, so that not all saliency objects at the edge are detected as background. Finally, the multi-layer features of the image are extracted to construct different diffusion maps and diffusion matrices. The similarity of nodesis reflected from multiple angles, and corresponding saliency maps acquired from the middle and high-level features of the image are nonlinearly fused to acquire the final saliency map. Compared withsome classical saliency object detection algorithms in the prior art, the method and terminal, which are provided by the invention, have the advantages that the accuracy of image saliency detection isimproved in the aspect of a common data set, and the problems that saliency object detection is not prominent and the background area cannot be well restrained in the prior art are solved.

The invention discloses a quantitative evaluation method for stability of a power grid. The method includes steps of acquiring measurement data related to power grid safety and stability through calculation and analysis of a power system; performing modeling on the random dynamic power system; based on the measurement data, analyzing the stability of the power grid by utilizing a critical slowing-down theory. The method is quick in calculation. A large amount of time domain simulation numerical integration is not needed in semi-analytical method; the semi-analytical method is very suitable fora condition with small diffusion matrix strength in a random process.

The invention discloses a method for predicting ion diffusion coefficients of damaged cement based composite materials. According to the method, regarding the microcosmic structure of damaged cement based composite materials which are discretized into a series of cube three-dimensional space lattices with equal size, each pair of adjacent cube three-dimensional space lattices are used as a lattice diffusion unit, wherein ion diffusion ability exists between each pair of adjacent cube three-dimensional space lattices, all the lattice diffusion units combine together to form a three-dimensional lattice ion transmission network, and each lattice is used as a diffusion node. Damage cracks are processed as hole phases, an ion diffusion matrix equation is established by using diffusion matrix equations between every two adjacent diffusion nodes in the three-dimensional lattice ion transmission network and combining ion concentration boundary conditions, solution is carried out on the ion diffusion matrix equation to obtain ion concentration distribution under a steady state, and finally the ion diffusion coefficients of the damaged cement based composite materials is obtained. The method for predicting the ion diffusion coefficients of damaged cement based composite materials can accurately predict ion diffusion ability change rules of the damaged cement based composite materials under the influences of freeze thawing, loading, air shrinkage and other conditions.

The invention discloses a customer data screening method based on a small sample non-uniform diffusion algorithm, relates to the technical field of data analysis, and solves the technical problem of accurately positioning customers. The method comprises the following steps: firstly, selecting two fields from a client database as two diffusion direction vectors, and selecting one field as a diffusion variable factor; establishing a two-dimensional coordinate system according to the two diffusion direction vectors; carrying out diffusion on the client database by adopting a non-uniform diffusionalgorithm; selecting a section of sub-matrix meeting a screening condition from the diffusion matrix; obtaining a sample point set through aggregation, randomly selecting a plurality of records froma client database as a control point set, analyzing the sample point set by adopting a correlation estimation expectation formula, removing unqualified sample points according to a correlation estimation expectation value, and finally obtaining a screening result of client data. The method provided by the invention is particularly suitable for small and micro enterprises with less basic customerdata.

The invention discloses a simple and easy-to-use laser night vision device with a good heat dissipation effect. The laser night vision device comprises a night vision objective lens, a camera, two laser devices, a power supply device, a memory, a display device, a control keyboard and a control device; the camera is arranged behind the night vision objective lens, the top surface of the camera isprovided with a cooling device, the cooling device comprises a heat insulating cover, a protective mesh pad, a vortex tube assembly and a cold air guiding diffusion matrix, the protective mesh pad isarranged in the heat insulating cover, and the vortex tube assembly and the cold air guiding diffusion matrix are arranged below the protective mesh pad; the two laser devices are arranged on the front surface of the camera, each laser device includes a fixation base and an infrared laser arranged on the corresponding fixation base, the power supply device is arranged below the camera, the memoryis arranged on the side surface of the camera, the display device is arranged on the rear surface of the camera, and the control keyboard is arranged on the front surface of the display device.