Entity

Time filter

Source Type


Ruiz S.,Centra Espanol de Metrologia CEM | Medina N.,Centra Espanol de Metrologia CEM
PTB - Mitteilungen Forschen und Prufen | Year: 2011

A comparison between the results of an uncertainties assessment, using different approaches, of the calibration of pressure standards (mercury column, piston cylinder assemblies and static expansion system) is made. First a classical GUM analysis is performed using the Welch-Satterthwaite formula and supposing different degrees of freedom for the uncertainties components estimated by the type B method. These results are compared with the ones obtained by Monte Carlo simulation suggested in the GUM Supplement 1. In all cases the same mathematical model is used and the same assumptions for the different uncertainty components are made. The obtained results demonstrate the equivalence of both methods for all cases except in the characterization of the static expansion system where GUM method reached different values due to the fact that the mathematical model used is significantly nonlinear. Source


Herranz D.,Centra Espanol de Metrologia CEM | Medina N.,Centra Espanol de Metrologia CEM | Ruiz S.,Centra Espanol de Metrologia CEM | Torres-Guzman J.,Centra Nacional de Metrologia CENAM
PTB - Mitteilungen Forschen und Prufen | Year: 2011

The static expansion system of CEM has been validated by a comparison with a force-balanced piston gauge and the static expansion system of CENAM by using a capacitive diaphragm gauge (CDG 133.32 Pa) and a spinning rotor gauge (SRG) as transfer standards. This paper shows the results of this validation. Source

Discover hidden collaborations