一种膛内多普勒测速修正方法

针对复杂电磁环境下膛内测速的重复性和精度低的问题,提出了一种非接触式膛内高精度测速方法,该方法在对膛内多普勒信号进行提取并去噪的基础上,利用S变换时频分析对预处理后的信号进行处理,然后采用谱峰搜索的方法来获得信号的瞬时频率,用能量重心校正法来提高结果精确度,最后根据多普勒原理,完成速度的测量;实验部分采用模拟信号和实际信号两种方式来验证该方法的可实施性;结果表明,该方法测速精度能够达到0.043 2%,相对于极值法和STFT法具有更小的误差。     

A study of time over threshold (TOT) technique for plastic scintillator counter

A new charge measurement method, time over threshold (TOT), has been used in some gas detectors lately. Here TOT is studied for TOF system, made of plastic scintillator counter, which can simplify the electronics of the system. The signal characteristics are measured and analyzed with a high quality oscilloscope, including noise, pedestal, signal amplitude, total charge, rise time and the correlation between them. The TOT and charge are related and can be fitted by some empirical formula. The charge measurement resolution by TOT is given and this will help the design of TOF electronics.     

基于深度卷积神经网络的红外图像超分辨率重建技术

由于器件及工艺等技术限制，红外图像分辨率相对可见光图像较低，存在细节纹理特征模糊等不足。对此，本文提出一种基于深度卷积神经网络（convolutional neural network,CNN）的红外图像超分辨率重建方法。该方法改进残差模块，降低激活函数对信息流影响的同时加深网络，充分利用低分辨率红外图像的原始信息。结合高效通道注意力机制和通道-空间注意力模块，使重建过程中有选择性地捕获更多特征信息，有利于对红外图像高频细节更准确地进行重建。实验结果表明，本文方法重建红外图像峰值信噪比（peak signal to noise ratio,PSNR）优于传统的Bicubic插值法以及基于CNN的SRResNet、EDSR、RCAN模型。当尺度因子为×2和×4时，重建图像的平均PSNR值比传统Bicubic插值法分别提高了4.57 dB和3.37 dB。