摘要：Signal drift and performance instability of brain-computer interface devices induced by the interface failure between rigid metal electrodes and soft human skin hinder the precise data acquisition of electroencephalogram(EEG).Thus,it is desirable to achieve a robust interface for brain-computer interface ***,a kind of polydopamine methacrylamide-polyacrylamide(PDMA-PAAM)hydrogel is *** improve the adhesion,dopamine is introduced into the polyacrylamide hydrogel,through the amino and catechol groups of dopamine in an organic-inorganic interface to build a covalent and non-covalent interaction.A strong attachment and an effective modulus transition system can be formed between the metal electrodes and human skin,so that the peeling force between the PDMAPAAM hydrogel and the porcine skin can reach 22 N m^(-1).In addition,the stable conductivity and long-term operating life of the PDMA-PAAM hydrogel for more than 60 days at room temperature are achieved by adding sodium chloride(NaCl)and glycerol,*** PDMA-PAAM hydrogel membrane fabricated in this work is integrated onto a flexible Au electrode applied in a brain-computer *** comparison,the collected EEG signal intensity and waveform are consistent with that of the commercial *** obviously,the flexible electrode with PDMA-PAAM hydrogel membrane is demonstrated to enable a more stable and userfriendly interface.

摘要：本文利用栅线投影测量方法研究了蜂窝夹层板、工字型及T型加筋板三种不同结构形式复合材料襟翼壁板在压缩载荷下的屈曲失稳行为,得到了不同形式结构件屈曲的全场离面位移分布规律,分析了各自的屈曲失稳模式。研究结果表明,栅线投影测量方法在大尺度复合材料结构失稳变形测试中具有可行性;在相同面板尺寸条件下,工字型加筋复合材料襟翼壁板屈曲临界载荷最大,承载能力最强。本文结果可为飞机复合材料结构设计提供实验依据。

摘要：监测轮轨力信号对于保障高速列车的安全运行、提高轨道线路的质量管理具有重要意义.然而,现有的轮轨力测试方法不能保证车轮在任意旋转角度下的测试精度与灵敏度,难以实现列车在高速行驶过程中轮轨力的实时连续测量.本文基于柔性电子技术设计了一款新型轮轨力传感器,在柔性衬底上设计环形应变栅结构,利用金属的压阻效应,获取环形区域内的整体变形随轮轨力变化的情况.垂向加载实验结果表明,柔性轮轨力传感器不仅具有良好的线性度,且在循环加载测试中表现出优异的稳定性和可重复性.更重要的是,该柔性轮轨力传感器能保证车轮在旋转任意角度情况下的测试精度与灵敏度.有限元仿真结果表明,在车轮内外两侧相对轴心等距离处布置柔性环形传感器,通过两侧传感器的输出信号可实现对轮轨横向力和垂向力的有效解耦.配合无线传感技术,柔性轮轨力传感器可实现高速列车轮轨力实时连续监测,对我国发展下一代智能高铁具有重要意义.