大截面光纤传像束及应用

介绍大截面光纤传像束的主要技术参数及其使用领域.  

基于BP神经网络的变速箱故障诊断方法研究

针对变速箱的工作时间不能真实反映实际健康状况的问题,通过提取变速箱的振动信号作为状态参数,建立了基于BP神经网络的变速箱故障诊断模型。该模型首先提取振动信号中对故障反映灵敏的成分作为特征值,获得BP神经网络的训练数据,并通过对比确定最优的隐含层节点数,确定BP神经网络的结构参数。模型训练结束后,以验证数据为例进行故障诊断研究,并对诊断结果进行评估。评估结果表明,该模型准确度高,具有较好的应用和推广价值。  

Switchable Dual－Wavelength Mode－Locked Er－Doped Fibre Laser Using a Bragg Grating in Polarization－Maintaining Fibre

A simple actively mode-locked fibre ring laser is proposed and successfully demonstrated to generate switchable dual-wavelength picosecond pulses using a Bragg grating in a polarization-maintaining fibre. The wavelength spacing specified by the grating is only 0.52nm. The proposed laser can be made to operate in stable dualwavelength or switch between wavelengths at room temperature, only by simple adjustment of a polarization controller.  

A Polarization Controlled Switchable Multiwavelength Erbium-Doped Fibre Laser

A polarization controlled switchable multiwavelength erbium-doped fibre laser with overlapping cavities is proposed. The wavelengths are specified by two Bragg gratings in polarization-maintaining PANDA fibre. The proposed laser can be designed to be operated in stable four-wavelength or wavelength switching modes only by