ROSSI G. B.

A general probabilistic model of the measurement process is discussed, showing how it can address both static and dynamic measurements. Emphasis is placed on the latter and two main kinds of dynamic measurements are considered: direct, where the goal is to monitor a phenomenon over time, and indirect, where an alternative representation is...

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The probabilistic modelling of measurement systems is discussed, showing how it provides a practical and effective way for addressing uncertainty evaluation, that does not require any commitment to specific philosophical schools, such as the frequentistic and the Bayesian ones. Firstly, different ways of modelling the same measuring device are...

The role of uncertainty in the acquisition and processing of experimental data has fundamental relevance, both theoretical and practical, for the metrological assessment of technology. The restitution procedures have been based, traditionally, on the 'error theory' and exploit a mainly statistical formulation in order to approach the 'true...

An interactive measurement procedure, used to perform the model identification of a multi-mass vibrating test rig, is discussed. The objective of this (secondary) observation chain is the collection of additional information on the test rig dynamic behaviour, in order to improve the accuracy of the measurements carried by the (principal)...

The need of technically assessing the properties of an increasing number of objects requires a considerable effort, for issuing the metrological standards, granting theoretical and practical traceability of both the ranking scales and the accuracy figures. The representational theory of measurements is deserving great interest since it provides...

An interactive computer program is described for use in the identification of vibrating mechanical systems. The expansion of the program to include an estimation process involving optimization by nonlinear programming is discussed and experiences in evaluating possible optimization strategies are briefly summarized. The program package has been...

The automatic restitution of measurement uncertainty with related current results is required for rationalising the specificity and for improving the effectiveness of the industrial instrumentation, used for standard quality engineering tasks. The paper introduces to a general probabilistic frame, based on the propagation of distribution...

Buoy networks aim at establishing near real-time data flow about the sea condition, with a possible direct interface with applications and services devoted to marine weather networks, with an expected significant impact on safety and efficiency. In this perspective, in the paper the estimation of directional wave spectra from buoys data is...

Systematic dynamic effects in linear measuring devices include possible amplification or attenuation, and phase shift of the spectral components of the indicated signal in respect to the original phenomenon. When this effect is non negligible, dynamic compensation should be applied. Yet in any case uncertainty on the modulus and the phase of...

An important task in biomechanics is human body articulations' internal torques measurement. This is known as a kinetic or inverse-dynamics problem. Its solution requires a combination of kinematic and dynamic measurements with a biomechanical model, involving subject-related anthropometric parameters. The uncertainty-evaluation thereof is here...

Biomechanical analysis of human movement is based on dynamic measurements of refer-ence points on the subject's body and orientation measurements of body segments. Collected data include positions' measurement, in a three-dimensional space. Signal enhancement by proper filtering is often recommended. Velocity and acceleration signal must be...

This paper deals with the spectral estimation of sea wave elevation time series by means of ARMA models. To start, the procedure to estimate the ARMA coefficients, based on the use of the Prony's method applied to the auto-covariance series, is presented. Afterwards, an analysis on how the parameters involved in the ARMA reconstruction...

The paper focuses on the tuning of Auto Regressive Moving Average (ARMA) models aimed at describing the spectral behaviour of sea wave elevation time series. The analysis considers mono-modal sea states, mainly due to the wind effect. The main problem related to the estimation of such models, starting from the wave elevation time series,...

The evaluation of the uncertainty due to systematic dynamic effects is addressed. When high dynamic performance is required, they should be compensated, by solving the associated inverse dynamic problem. When instead they are considered compatible with the target uncertainty, they may be simply included in the uncertainty budget. Furthermore,...

The approval of the European Measuring Instrument Directive on April 2004 renews completely the legal metrology sector, proposing a "new approach" aiming to technical normalization and harmonization and toward a "global approach" to evaluation and conformity. According to the principles of the "new approach" regulatory model, the Directive...