XIX IMEKO World Congress Fundamental and Applied Metrology September 6−11, 2009, Lisbon, Portugal ESTIMATION OF POSITIVE PARAMETERS IN FORM AND ROUGHNESS ASSESSMENT

نویسندگان

  • Alistair B. Forbes
  • João A. Sousa
چکیده

− The assessment of the geometry of artefacts in length metrology is concerned with estimating dimension, form and roughness. While all three are positive quantities, the evaluation of form and roughness are problematic, mainly because the values of the parameters to be measured are often of the same order as the measurement uncertainty. Furthermore, random effects associated with a measurement system will in general bias the estimate of parameter. This paper discusses these issues, using a Bayesian approach in which prior distributions are used to ensure parameter estimates are physically meaningful.

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تاریخ انتشار 2009