滴头流量偏差系数测量过程中不确定度评定方法探讨

为了量化滴头流量偏差系数检测的误差水平、提高检测数据可靠性，提供滴头流量偏差系数的不确定度，该文根据室内滴头流量偏差系数实测数据，开展不确定度评定方法的比较分析，探讨基于2种用于对观测数据进行统计分析的A类评定方法的滴头流量偏差系数不确定度评定效果和适用性。结果表明，A类标准不确定度较之用不同于对观测数据进行统计分析的B类标准不确定度对合成标准不确定度的影响较大，A类最大熵法在95%概率下滴头流量偏差系数的扩展不确定度高出常规法6%左右，滴头流量偏差系数的分布密度函数最为接近实测数据，且相应的偏度系数也高于常规方法，但其要求的最低试验重复数据量则是常规方法的1倍以上。在产品检测结果的不确定度评定工作中，建议应尽量使用有利于提高不确定度评定准确性的A类最大熵法。

Discussion on uncertainty evaluation method for variation coefficient of drippers discharge in measurement

In order to give the scope of error and enhance the reliability of test data, it is necessary to the uncertainty for coefficient of variation of drippers discharge. The comparison analysis for coefficient of variation of drippers discharge uncertainty evaluation method is supported by test data, so the effect and adaptability of two A—type uncertainty evaluation methods which based on series of test data were discussed. The conclusion was that the proportion of A—type standard uncertainty was more than B—type standard uncertainty which doesn’t based on series of test data among the compound standard uncertainty, and the expanded uncertainty of maximum entropy was higher 4% than normal method in 95% probability for A—type evaluation, and the density distributing function of maximum entropy method matched the test data preferably, and also eccentricity coefficient of maximum entropy method was adaptability, but the quantity of test date of maximum entropy method was over 1 times than normal method. The maximum entropy method, which can improve the accurate of uncertainty evaluation.