Abstract: A method for synthesizing arbitrary distribution noise signal includes two parts. An upper computer fits H given distribution function ƒ(x) to obtain H pluralities of K pairs of means ?kh and variances ?kh, by using Expectation Maximization algorithm based on a weakened Gaussian Mixture Model. An FPGA stores H pluralities of K pairs of means ?kh and variances ?kh into RAM, function values that box-muller transformation needs into ROM 1 and ROM 2, then read out two function values and multiply them to obtain random number xn, means ?kh and variances ?kh are read out from RAM to synthesizing kth Gaussian noise signal yknh, after amplitude limitation and normalization, obtained analogy signal is amplified Amax?Amin times and set bias voltage to Amin to obtain analogy noise signal with amplitude interval. An arbitrary distribution noise signal with specific distribution is outputted.

Abstract: A fault diagnosis method for the RF front-end circuit of a MIMO system includes using a Synchronous Enhancement Extracting Transform (SEET) to pre-process the acquired fault signal to extract fault feature, creating a fault identification model fused by a complex field based asymmetric convolutional neural network and a complex field based multi-head attention module to assign fault feature weights, extract key feature and identify fault status. The SEET can extract fault feature components, and calculate its real field feature and imaginary field feature to obtain a real field two-dimensional matrix i and an imaginary field two-dimensional matrix q, thus an enhanced time-frequency feature is obtained. The fault identification model is used for a transform from a complex field feature space to a high dimensional space and realizing the assignment of fault feature weights, key features extraction and fault status identification.

Abstract: A random transient power test signal generator based on three-dimensional memristive discrete map, which utilizes a three-dimensional parallel bi-memristor Logistic map module to generate two pseudo-random sequences, and based on the sequences, uses two waveform output modules to generate transient voltage and transient current signals respectively, thus the random transient power testing signal is obtained. The map can significantly improve the complexity of chaos and greatly extend its range of chaos. In addition, a performance evaluation shows the map has more robust hyperchaotic behavior in much larger chaos range. Moreover, the random sequences generated by the map module combines with DDS, which can generate a transient power signal with completely random period, starting phase and ending phase.

Abstract: A method for high-precision true color three dimensional reconstruction of mechanical component. Firstly performs image acquisition: the left and right high-resolution grayscale cameras are fixed at same height and spaced at certain distance, an optical transmitter fixed between the two grayscale cameras, and low-resolution color camera fixed above optical transmitter, thus images of measured high-precision mechanical component are shot. Then performs image processing: all images are transmitted to a computer, which uses image processing to record surface information of measured high-precision mechanical component in the point cloud by high-precision true color three-dimensional reconstruction, which reflects color texture information of the surface, so as to realize the non-contact high-precision true color three dimensional reconstruction of high-precision mechanical component.

Abstract: The present invention provides a method for quantitatively identifying the defects of large-size composite material based on infrared image sequence, firstly obtaining the overlap area of an infrared splicing image, and dividing the infrared splicing image into three parts according to overlap area: overlap area, reference image area and registration image area, then extracting the defect areas from the infrared splicing image to obtain P defect areas, then obtaining the conversion coordinates of pixels of defect areas according to the three parts of the infrared splicing image, and further obtaining the transient thermal response curves of centroid coordinate and edge point coordinates, finding out the thermal diffusion points from the edge points of defect areas according to a created weight sequence and dynamic distance threshold ?ttr×dp_max, finally, based on the thermal diffusion points, the accurate identification of quantitative size of defects are completed.

Abstract: A method for high-precision true color three dimensional reconstruction of mechanical component. Firstly performs image acquisition: the left and right high-resolution grayscale cameras are fixed at same height and spaced at certain distance, an optical transmitter fixed between the two grayscale cameras, and low-resolution color camera fixed above optical transmitter, thus images of measured high-precision mechanical component are shot. Then performs image processing: all images are transmitted to a computer, which uses image processing to record surface information of measured high-precision mechanical component in the point cloud by high-precision true color three-dimensional reconstruction, which reflects color texture information of the surface, so as to realize the non-contact high-precision true color three dimensional reconstruction of high-precision mechanical component.

Abstract: The present invention provides a method for quantitatively identifying the defects of large-size composite material based on infrared image sequence, firstly obtaining the overlap area of an infrared splicing image, and dividing the infrared splicing image into three parts according to overlap area: overlap area, reference image area and registration image area, then extracting the defect areas from the infrared splicing image to obtain P defect areas, then obtaining the conversion coordinates of pixels of defect areas according to the three parts of the infrared splicing image, and further obtaining the transient thermal response curves of centroid coordinate and edge point coordinates, finding out the thermal diffusion points from the edge points of defect areas according to a created weight sequence and dynamic distance threshold ?ttr×dp_max, finally, based on the thermal diffusion points, the accurate identification of quantitative size of defects are completed.