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Silvio B. Melo, Carlos C. Dantas, Emerson A. de O. Lima, Francisco P. M. Simões, Eric F. de Oliveira,Valdemir. A. dos Santos
RECONSTRUCTION OF RADIAL CATALYST CONCENTRATION DISTRIBUTION IN AN EXPERIMENTAL TYPE FCC RISER

A gamma ray tomographic reconstruction of catalyst concentration distribution in laboratory experiments is presented. The images are generated by gamma transition measurements in an experimental riser simulating flow experiments. The manual scanner is adequate for mapping radial catalyst concentration distribution under spatial resolution of 0.002 m and density resolution of 10 kg/m³.

Jose U. Delgado, Maria Cd. M. de Almeida, Roberto Poledna
PRECISE DETERMINATION OF GE DETECTOR EFFICIENCY CURVE FOR OBTAINING ACTIVITIES IN RADIONUCLIDES GAMMA-EMITTERS

An efficiency curve obtained in a gamma-ray spectrometric system using a high purity germanium detector and radioactive standards of 133Ba, 152Eu and 166mHo in an energy range of 50 to 1400 keV was established for metrological purposes. To do this, the efficiency response of the detector was used considering 29 different energies. This allowed calibrating various gammaemitter radioactive point sources, within of a 50 kBq to 550 MBq activity range, with expanded uncertainties below 2.5% at two-sigma confidence level (k=2). The obtained activity value for 22Na was validated by sum-peak coincidence method.

Karl H. Ruhm
MODELLING OF NON-IDEAL MEASURING PROCESSES – PREREQUISITE FOR ERROR AND UNCERTAINTY ANALYSIS

The determination of the uncertainty of measurement results is one of the most demanding but unpopular tasks in metrology. One of several reasons for this fact is the lack of well-structured models of non-ideal measurement processes on one hand and of qualification processes, which determine measurement uncertainties, on the other hand. Easily available and universally valid models would greatly help to improve measurement quality. But since process modelling is very laborious, practitioners are additionally confronted with cost-benefit questions. This paper starts with the most popular but rather incomplete error model and, on the basis of Signal and System Theory, derives a quantitative structure of the non-ideal measurement process. This structure is comprehensive and open for further and more challenging extensions.

Jean-Claude Krynicki
INTRODUCTION TO “SOFT” METROLOGY

Outside of the classical physical and chemical metrologies, there is a large field of measurement, which is called dimensionless or “soft “ metrology by analogy with hard and soft sciences.
The objective of this presentation is to provide an overview of this field, to analyze the methods used and their linkage to classical metrology.
The author will take 3 examples, an historical one, the measurement of human character, and two modern research fields, software usability and customer satisfaction.
He will also show the recent efforts from the European Commission, as part of the New Emerging Sciences and Technologies program (N.E.S.T.), to increase the objectivity of these measurements.

I. M. Barbosa, E. del Moral Hernandez, M. L. C. C. Reis, O. A. F. Mello
MEASUREMENT UNCERTAINTY CONTRIBUTION TO THE CALIBRATION CURVE FITTING OF AN AERODYNAMIC EXTERNAL BALANCE USING MLP ARTIFICIAL NEURAL NETWORK

The aim of this study is to fit a calibration curve to a multivariate system. The experimental data are generated from the calibration of the aerodynamic external balance of the subsonic wind n.º 2, the TA-2, of the Brazilian Aerospace Institute, IAE. Multilayer Perceptrons (MLPs) Artificial Neural Networks are employed. To fit the calibration curve, the MLPs are submitted to the learning process. The measurement uncertainties are taken into consideration, through the modification of the MLP learning algorithm, which in its classical approach, considers the data points free from error sources. The results of both methodologies, learning algorithm endowed or without uncertainties, are compared.

Andréa Cristina Konrath, Gustavo Daniel Donatelli , Daniel Hamburg-Piekar
THE APPLICATION OF MONTE CARLO SIMULATION TO EVALUATE THE UNCERTAINTY OF CONTROL CHART PERFORMANCE INDICES

This paper presents the preliminary results of a research aimed to evaluate the effect of the measurement process on the effectiveness of control charting. To achieve this goal, the authors propose propagating the uncertainty of measurement through the control charting process using the Monte Carlo simulation technique (MCS).
Results are shown, evidencing that measurement uncertainty affects significantly the effectiveness of control charts an that the influence is different depending on the nature of the uncertainty contribution.

Gilles Mauris
PROPAGATION OF MEASUREMENT UNCERTAINTY EXPRESSED BY A POSSIBILITY DISTRIBUTION WITH COVERAGE-INTERVAL-BASED SEMANTICS

The main purpose of this paper is to present a possibility theory-based generalization of conventional interval propagation to coverage intervals. Indeed, the whole set of coverage intervals for all the probability levels stacked on top of one another constitutes a possibility distribution. Thus by slight modifications of Zadeh’s extension principle, we will prove that it is possible to compute the coverage intervals of an indirect measurement from many other measurements (possibly dependent) by a known non decreasing relationship.

Edivaldo A. Bulba, ; Victor R. Svoll
ANOTHER ARGUMENT TO CONSIDER THE RELIABILITY OF THE UNCERTAINTY TYPE B SIMILAR TO TYPE A

The ISO-GUM express that the standard deviation of the experimental standard deviation of the mean q obtained for ratio σ[s(q)]/σ(q) has a not negligible value for practical values of n, and therefore that Type A evaluations of the standard uncertainty are not necessarily more reliable than Type B evaluations. Although this correct comparison either, the assertion based on the value of the σ(q) is the not best, in way that this work to consider other relation as argument for this comparison.

Oleh Velychko
ACTIVITY OF INTERNATIONAL AND REGIONAL ORGANIZATION FOR GLOBALIZATION OF THE WORLD ECONOMY

Paper considers the problems of globalisation of the world economy and the role of national metrological services, main directions activity of international and regional organizations in the field of metrology.

Patrizia Ciarlini, Umberto Maniscalco
MIXTURE OF SOFT SENSORS FOR MONITORING AIR AMBIENT PARAMETERS

Monitoring the physical or chemical conditions of the materials composing a monument can be achieved in a not invasive way by using trained neural networks. Soft sensors based on Elman neural networks have been developed to provide virtual measurements at locations of the monument surface using only the measurements acquired by an Air Ambient Monitor Station located nearby the monument. Here we improve the accuracy of the virtual measurements by using averaging techniques or mixture of such soft sensors. The accuracy of these virtual instruments is analyzed and compared from a metrological and statistical point of view.

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