用偏倚缩减法确定条件采样的门限  

Determination of thresholds of conditional sampling by bias reduction procedure

作　　者：陈桂英[1] 王振东[2] 姜楠[2] 

机构地区：[1]武警医学院物理学教研室,天津300162 [2]天津大学机械学院力学系

出　　处：《武警医学院学报》2000年第2期100-102,共3页Acta Academiae Medicinae CPAPF

基　　金：国家自然科学基金

摘　　要：目的 :确定条件采样法的客观门限。方法 :用偏倚缩减法计算湍流信号自相关函数。根据自相关函数的第二峰值对应的延迟时间与湍流的平均猝发周期的实验结果确定 MU-LEV-EL、 VITA法的门限。结果 :用偏倚缩减法确定的平均猝发周期比用其它三种方法最接近实际测量到的湍流平均猝发周期 ,据此 ,用统计的方法确定出的条件采样门限值更客观、更准确。结论 :用偏倚缩减法确定出条件采样 MU-LEVEL法、 VITA法的门限值较其它三种方法客观、准确。Objective:To determine the reasonable thresholds of conditional sampling scheme.Methods:Autocorrelation was calculated by bias reduction procedure,using the experimental results of the delay time corresponding to the second peak of autocorrelation to determine the thresholds of conditional sampling scheme for VITA and Mu leve.Results:The average bust period determined by bias reduction procedure was very close to the average bust period measured in comparison with other three methods.More reasonable thresholds of conditional sampling were thus obtained.Conclusion:More reasonable thresholds of conditional samples scheme for VITA and mu level may be determined by bias reduction procedure.

关 键 词：偏倚缩减法 相干结构 门限 湍流 

分 类 号：O357.5[理学—流体力学]