The 'dream' of acoustic emission (AE) testing is to get the acoustic source characteristics from AE signals, especially when evaluating aging pressure vessels. In this paper, the wavelet transform was used to...The 'dream' of acoustic emission (AE) testing is to get the acoustic source characteristics from AE signals, especially when evaluating aging pressure vessels. In this paper, the wavelet transform was used to analyze different AE signals from cracks (surface and inner), pencil-lead-breakage and leakage. These acoustic sources were applied on an actual pressure vessel. While the vessel experienced hydraulic pressure, their AE signals were acquired by a digital AE testing system with a wide frequency band transducer and a high speed A/D converter. Then, the digital signals were analyzed using the wavelet transform method. Correlation coefficients of the transformed data show that the different acoustic sources can be easily identified.展开更多
目的研究非狭窄性斑块在不明原因栓塞性脑卒中(ESUS)发病机制中的作用。方法收集2018年1月1日~12月31日在上海市第一人民医院神经内科住院诊治并完成相关检查的59例ESUS患者影像学资料,通过Osirix软件对患者HRMRI图像序列进行3D重组,用V...目的研究非狭窄性斑块在不明原因栓塞性脑卒中(ESUS)发病机制中的作用。方法收集2018年1月1日~12月31日在上海市第一人民医院神经内科住院诊治并完成相关检查的59例ESUS患者影像学资料,通过Osirix软件对患者HRMRI图像序列进行3D重组,用Vessel MASS软件进行图像分析责任血管中责任斑块与病灶对侧非责任血管中非责任斑块的血管官腔面积、血管面积、斑块面积、斑块负荷、斑块内高信号、斑块表面规则性及血管重构指数和血管狭窄率。结果在59例ESUS患者颅内血管中发现责任斑块43处,非责任斑块41处。与非责任斑块比较,责任斑块面积更大(0.73±0.13mm 2 vs 0.04±0.02mm 2,P=0.000),斑块负荷更大(0.27±0.13PB vs 0.21±0.10PB,P=0.019),并且责任斑块内高信号比例更高(69.77%vs 46.34%,P=0.029)。另外与非责任血管比较,责任血管出现正向重构的比例更高(65.12%vs 41.46%,P=0.030)。结论ESUS患者中责任斑块与非责任斑块比较,具有斑块面积及斑块负荷更大、正向重构比例高、斑块内高信号及斑块表面不规则等斑块不稳定性特征,提示非狭窄性动脉粥样硬化斑块可能是ESUS患者发病机制中重要的栓子来源。展开更多
文摘The 'dream' of acoustic emission (AE) testing is to get the acoustic source characteristics from AE signals, especially when evaluating aging pressure vessels. In this paper, the wavelet transform was used to analyze different AE signals from cracks (surface and inner), pencil-lead-breakage and leakage. These acoustic sources were applied on an actual pressure vessel. While the vessel experienced hydraulic pressure, their AE signals were acquired by a digital AE testing system with a wide frequency band transducer and a high speed A/D converter. Then, the digital signals were analyzed using the wavelet transform method. Correlation coefficients of the transformed data show that the different acoustic sources can be easily identified.
文摘目的研究非狭窄性斑块在不明原因栓塞性脑卒中(ESUS)发病机制中的作用。方法收集2018年1月1日~12月31日在上海市第一人民医院神经内科住院诊治并完成相关检查的59例ESUS患者影像学资料,通过Osirix软件对患者HRMRI图像序列进行3D重组,用Vessel MASS软件进行图像分析责任血管中责任斑块与病灶对侧非责任血管中非责任斑块的血管官腔面积、血管面积、斑块面积、斑块负荷、斑块内高信号、斑块表面规则性及血管重构指数和血管狭窄率。结果在59例ESUS患者颅内血管中发现责任斑块43处,非责任斑块41处。与非责任斑块比较,责任斑块面积更大(0.73±0.13mm 2 vs 0.04±0.02mm 2,P=0.000),斑块负荷更大(0.27±0.13PB vs 0.21±0.10PB,P=0.019),并且责任斑块内高信号比例更高(69.77%vs 46.34%,P=0.029)。另外与非责任血管比较,责任血管出现正向重构的比例更高(65.12%vs 41.46%,P=0.030)。结论ESUS患者中责任斑块与非责任斑块比较,具有斑块面积及斑块负荷更大、正向重构比例高、斑块内高信号及斑块表面不规则等斑块不稳定性特征,提示非狭窄性动脉粥样硬化斑块可能是ESUS患者发病机制中重要的栓子来源。
