Hyperspectral Detection and Unmixing of Subpixel Target Using Iterative Constrained Sparse Representation

Background: This study is carried out targeting the problem of slow response time and performance degradation of imaging system caused by large data of medical ultrasonic imaging. In view of the advantages of CS, it is applied to medical ultrasonic imaging to solve the above problems. Objective: Under the condition of satisfying the speed of ultrasound imaging, the quality of imaging can be further improved to provide the basis for accurate medical diagnosis. Methods: According to CS theory and the characteristics of the array ultrasonic imaging system, block compressed sensing ultrasonic imaging algorithm is proposed based on wavelet sparse representation. Results: Three kinds of observation matrices have been designed on the basis of the proposed algorithm, which can be selected to reduce the number of the linear array channels and the complexity of the ultrasonic imaging system to some extent. Conclusion: The corresponding simulation program is designed, and the result shows that this algorithm can greatly reduce the total data amount required by imaging and the number of data channels required for linear array transducer to receive data. The imaging effect has been greatly improved compared with that of the spatial frequency domain sparse algorithm.

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Sparse Representation Based Dielectric Loss Angle Measurement

The Open Electrical & Electronic Engineering Journal ◽

10.2174/1874129001509010566 ◽

2015 ◽

Vol 9 (1) ◽

pp. 566-570

Author(s):

Zhang Ji ◽

Jianfeng Zheng

Keyword(s):

Dielectric Loss ◽

Power Systems ◽

Sparse Representation ◽

Precise Measurement ◽

Angle Measurement ◽

Measuring Error ◽

Loss Angle ◽

Analysis Method ◽

Electric Capacity ◽

Dielectric Loss Angle

Precise measurement of dielectric loss angle is very important for electric capacity equipment in recent power systems. When signal-to-noise is low and fundamental frequency is fluctuating, aiming at the measuring error of dielectric loss angle based on some recent Fourier transform and wavelet transform harmonics analysis method, we propose a novel algorithm based on sparse representation, and improved it to be more flexible for signal sampling. Comparison experiments describe the advantages of our method.

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Image Fusion Method Based on Multi-scale Directional Fast Guided Filter and Convolutional Sparse Representation

Recent Advances in Electrical & Electronic Engineering (Formerly Recent Patents on Electrical & Electronic Engineering) ◽

10.2174/2352096511666180607101743 ◽

2019 ◽

Vol 12 (3) ◽

pp. 263-269

Author(s):

Liu Xian-Hong ◽

Chen Zhi-Bin

Keyword(s):

Image Fusion ◽

Sparse Representation ◽

Filter Bank ◽

Guided Filter ◽

Fusion Method ◽

Edge Preserving ◽

Directional Information ◽

Multi Scale ◽

Directional Filter ◽

Image Fusion Method

Background: A multi-scale multidirectional image fusion method is proposed, which introduces the Nonsubsampled Directional Filter Bank (NSDFB) into the multi-scale edge-preserving decomposition based on the fast guided filter. Methods: The proposed method has the advantages of preserving edges and extracting directional information simultaneously. In order to get better-fused sub-bands coefficients, a Convolutional Sparse Representation (CSR) based approximation sub-bands fusion rule is introduced and a Pulse Coupled Neural Network (PCNN) based detail sub-bands fusion strategy with New Sum of Modified Laplacian (NSML) to be the external input is also presented simultaneously. Results: Experimental results have demonstrated the superiority of the proposed method over conventional methods in terms of visual effects and objective evaluations. Conclusion: In this paper, combining fast guided filter and nonsubsampled directional filter bank, a multi-scale directional edge-preserving filter image fusion method is proposed. The proposed method has the features of edge-preserving and extracting directional information.

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