量值传递中绝对测量与相对测量转化实例的数理分析（一）

摘要

A measurement model for verifying the thermal resistance was analyzed by two kinds of verification methods specified in verification regulations .By substituting assumptive parameters under ideal conditions into measurement model , mathematical expression with clear , simple and visualized physical conceptions can be obtained .The analysis and results show that: striking difference of verification results of verified samples may be caused with a small difference of applied verification methods on a same standard verification device .This is caused by the change of value source of a parameter of the standard device , which inadvertently turns the verification process of relative measurement into an absolute measurement , so the measurement result deviation of measuring system is significantly increased .Therefore ,quantity transmission methods are of great importance in the process of verification .If improper methods are applied , expected purpose will not be realized even if the best equipment is used .%以检定热电阻的一个测量模型，按检定规程规定的两种检定方法进行分析。以假设的较理想条件下的参数代入测量模型，得到物理概念清晰、简单直观的数理表达式。从分析过程和结果可以看出：在同一个标准装置上检定，因采用的检定方法的一点不同，会导致被检样品检定结果误差的惊人差别。究其原因，是标准器一个参数的取值来源变化，把一个相对测量的检定过程不经意变成一次绝对测量，使测量系统测量结果的误差显著增大，差别之大超出想象。由此可见量值传递方法在检定工作中的重要性，如方法选用不当，使用再好的设备也达不到预期的目的。