期刊文献+
共找到2篇文章
< 1 >
每页显示 20 50 100
树根桩的反射波法低应变测试
1
作者 赵彬 王大远 《盐城工学院学报(自然科学版)》 CAS 2003年第3期67-69,共3页
从树根桩特性入手,分析了树根桩反射法低应变测试过程中存在波速难确定、龄期短强度低、土层变化等因素对测试的影响,以及直径小敲击点控制难等方面的难点,结合自己的经验,提出了根据地区特点综合确定波速、提高敲击力度解决砂浆强度低... 从树根桩特性入手,分析了树根桩反射法低应变测试过程中存在波速难确定、龄期短强度低、土层变化等因素对测试的影响,以及直径小敲击点控制难等方面的难点,结合自己的经验,提出了根据地区特点综合确定波速、提高敲击力度解决砂浆强度低的问题、根据地质勘测报告。结合反射波理论综合分析,采取在桩头处理时增大敲击面积解决敲击点难控制等方法,从而顺利地进行树根桩低应变测试,并得出较精确的结果。综合工程图形实例,对以上问题进行比较,验证各种方法的可行性及准确性。 展开更多
关键词 树根桩 反射波法低应变测试 地质 敲击力度 砂浆 强度 建筑 桩基
下载PDF
An efficient method of addressing ectopic beats:new insight into data preprocessing of heart rate variability analysis 被引量:1
2
作者 Feng WEN Fang-tian HE 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2011年第12期976-982,共7页
Heart rate variability(HRV) analysis is affected by ectopic beats.An efficient method was proposed to deal with the ectopic beats.The method was based on trend correlation of the heart timing signal.Predictor of R-R i... Heart rate variability(HRV) analysis is affected by ectopic beats.An efficient method was proposed to deal with the ectopic beats.The method was based on trend correlation of the heart timing signal.Predictor of R-R interval(RRI) value at ectopic beat time was constructed by the weight calculation and the slope estimation of preceding normal RRI.The type of ectopic beat was detected and replaced by the predictor of RRI.The performance of the simulated signal after ectopic correction was tested by the standard value using power spectrum density(PSD) estimation,whereas the results of clinical data with ectopic beats were compared with the adjacent ectopic-free data.The result showed the frequency indexes after ectopy corrected had less error than other methods with the test of simulated signal and clinical data.It indicated our method could improve the PSD estimation in HRV analysis.The method had advantages of high accuracy and real time properties to recover the sinus node modulation. 展开更多
关键词 Frequency domain Ectopic beat Heart rate variability(HRV) Power spectrum density
原文传递
上一页 1 下一页 到第
使用帮助 返回顶部