The publication of the Guide to Expression Uncertainty in Measurement (GUM), and later its Supplement 1, can be considered landmarks field metrology. second these documents recommends a general Monte Carlo method for numerically constructing probability distribution measurand given distributions input quantities. output used estimate fixed value calculate limits an interval wherein that is expected found with probability. approach 1 not restricted linear or linearized models (as GUM) but it...

The 'Guide to the Expression of Uncertainty in Measurement' (GUM) has been use for more than 20 years, serving its purposes worldwide at all levels metrology, from scientific industrial and commercial applications. However, GUM presents some inconsistencies, both internally with respect two later Supplements. For this reason, Joint Committee Guides Metrology, which is responsible these documents, decided that a major revision needed. This will be done by following principles Bayesian...

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Measurement data subject only to random effects can be evaluated within the frameworks of conventional as well Bayesian statistical theory. In this paper, both viewpoints are presented and examples including Gaussian, uniform Poisson statistics discussed. The cases produced by different observers, quantities expressed measurement models involving systematic effects, also briefly touched upon. It is shown that, although in most practical uncertainty intervals obtained from repeated...

Two methods to measure the diffusion coefficient of a species in liquid by optical interferometry were compared. The tested on 1.75 M NaCl aqueous solution diffusing into water at 26 °C. Results D = 1.587 × 10−9 m2 s−1 with first method and 1.602 second method. Monte Carlo simulation was used assess possible dispersion these results. standard uncertainties found be order 0.05 both methods. We that value obtained either is very sensitive magnification system, if slow measurement time does not...

In this paper we review and extend the state of art in algorithms that have been developed to tomographically reconstruct 1-D 2-D refractive-index fields presence significant refraction. A perturbation approach two iterative procedures were tested compared numerical simulation holographic interferometry experiments. Due nonlinearity problem, it is very difficult draw general conclusions with respect behavior algorithms, which divergent examples presented here. contrast, technique, easiest...

Evaluating the Measurement Uncertainty is a book written for anyone who makes and reports measurements. It attempts to fill gaps in ISO Guide Expression of Measurement, or GUM, does pretty thorough job. The GUM was with intent being applicable by all metrologists, from shop floor National Metrology Institute laboratory; however, has often been criticized its lack user-friendliness because it primarily filled statements, but little explanation. gives lots explanations. well use many good...

Bayesian analysis is used to evaluate the standard uncertainty and coverage probability corresponding a measurand Z modelled as sum of two quantities X Y. It assumed that information about cast in form Gaussian or rectangular density functions, whereas Y consists series independently measured values. Prior also taken into account. Results are compared with those obtained using procedure recommended ISO Guide Expression Uncertainty Measurement. shown application Bayes' theorem leads an...

The analysis of key comparison data is at the focus metrology-related research and many papers have been published on this issue in recent years. Typically, approaches make use quoted combined uncertainties. We propose an approach which based more detailed uncertainty information. assume that each participating laboratories has knowledge about precision its measurements and, addition, provides a probability density function (PDF) encodes assessment size bias. Only case single stable...

Since the type A evaluation of standard uncertainty according to rules given in ISO Guide Expression Uncertainty Measurement does not take into account that arises from limited resolution indicating devices, we show this design note treatment problem calls for a quantity about which no statistical information is available; therefore, its has be derived B evaluation.

The most widely used procedure for finding the value of a quantity from data obtained interlaboratory comparisons involves calculating inverse-variance weighted mean laboratories' estimates. This method produces adequate results if are consistent. However, sometimes consistency test reveals possible existence outliers that nevertheless have to be included in evaluation task. In this paper Bayesian understanding probability is derive three methods may applied case when appear inconsistent....

In some situations measurement results are stated without correcting for known systematic effects. It is shown here that this can be done as long the uncertainty associated with uncorrected result properly evaluated. Since procedure produces an enlarged uncertainty, it strongly advised corrected always stated.

When constructing a coverage interval from the probability density function that describes state of knowledge about measurand, it seems reasonable to expect long-run success rate will be equal stipulated probability. Through specific example, validity this criterion is examined.

Current recommendations for evaluating uncertainty of measurement are based on the Bayesian interpretation probability distributions as encoding state knowledge about quantities to which those refer. Given a model that relates an output quantity one or more input quantities, distribution former is obtained by propagating latter according axioms calculus and also, if data available, applying Bayes' theorem.

In industrial practice, the decision to accept or reject an inspected item is usually made on basis of measurement information. Since this information rarely complete, it not possible in general be absolutely certain about value measurand. As a consequence, incorrect decisions may made. paper, formulae for probabilities improperly accepting rejecting are derived. Bayesian statistics provides theoretical framework, and use Principle Maximum Entropy. Applications inspection workpieces...

Quantities that lie within inexactly prescribed intervals arise frequently. A formula for the maximum entropy probability density function (PDF) describes state of knowledge such a quantity is given in Supplement 1 to Guide Expression Uncertainty Measurement. However, this applies only case which limits interval are known subintervals equal lengths centred on best estimates limits. In paper, PDF derived not so restricted.

If you search the web for `measurement uncertainty', will obtain a list of some 14500 items. This confirms, if necessary, pervasiveness this concept. Curiously, I am not aware scientific book specifically devoted to evaluation measurement uncertainty. Therefore, certainly deserves careful consideration. go through it, quickly realize that it is multi-faceted book. It an introduction metrology, especially in chapter 1, due T J Quinn, FRS, Director Bureau International des Poids et Mesures....