• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议> >Statistical limitations of the effective density based on the K-distribution ~echography
【24h】

Statistical limitations of the effective density based on the K-distribution ~echography

机译：基于K分布〜回波描记术的有效密度的统计局限性

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

In echography, the radiofrequency signal envelope which comes from non-periodic media with low density or clustered scatterers shows deviations from Rayleigh statistics, It has been shown recently that the K-distribution is then a good model. This model contains a parameter, /spl alpha/, from which an estimation of the effective density of scatterers in media can be made. In this work, some statistical properties of this estimator, i.e. its bias and variance versus the sample size, are studied. The bias and variance have been analytically calculated and compared with numerical simulation for media with scatterers densities ranging in a 1 to 20 ratio. The effects induced by attenuation and noise are also discussed. These results give the limits of the experimental conditions for which the bias and variance of /spl alpha/ estimation are acceptable. The effective density of 3 types of foams has been estimated and compared with other acoustical parameters.
机译：在回波描记术中，来自低密度非周期性介质或聚集散射体的射频信号包络显示出与瑞利统计量的偏差。最近证明，K分布是一个很好的模型。该模型包含一个参数/ spl alpha /，可以从中估算介质中散射体的有效密度。在这项工作中，研究了该估计量的一些统计属性，即其偏倚和方差与样本量之间的关系。已对斜率和方差进行了解析计算，并与散射密度为1到20的介质的数值模拟进行了比较。还讨论了由衰减和噪声引起的影响。这些结果给出了可以接受/ spl alpha /估计的偏差和方差的实验条件的限制。估计了三种泡沫的有效密度，并将其与其他声学参数进行了比较。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号