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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.

André Luiz Meira de Oliveira, Carlos Alberto Schneider, Gustavo Andrade Maestri
THE REMOTE SERVICES LABORATORY AS A METROLOGY KNOWLEDGE MANAGEMENT INTEGRATOR AND ITS IMPACTS ON SOCIAL RESPONSIBILITY

The demands for qualified metrology consultancy and technical support are increasing exponentially due to the current market conditions. Consumers are more aware of quality issues than ever before, informed by the mass media and supported by organizations of consumer–right defense. Companies are investing in better testing and inspection facilities to bear the development of new products and processes, to maintain the processes operating on target with minimum variance and to segregate non-conforming products before they can reach the hands of the customer. In this scenery, there is a complete collection of free-lance professionals, technology centers and other companies and organizations that provide consultancy and metrology services pushed by the above-mentioned demand. Central LASAR is a remote laboratory that appeared as a channel to normalize these relations. The solution has been tested, showing that the approach is technically and economically feasible for the service suppliers as well as for their customers, including the increasing of social coresponsibility aspects between customers and suppliers.

H.L. Amos, R.J. Gunn, M. Buxton
ENSURING THE ADVANCEMENT OF METROLOGY IN AREAS SUPPORTING SUSTAINABLE DEVELOPMENT THROUGH IMPROVEMENTS IN THE BUDGET ALLOCATION PROCESS

Metrology is developing as a field, and in the United Kingdom (UK) this requires development of the budget allocation process to ensure funding is provided to all areas. A research project is being undertaken within the UK National Measurement System aimed at creating a more balanced approach to ensure funding is granted at the appropriate level in areas of metrology for which the justification is non-economic.

T. Sanponpute, V. Sanh, D. D. Nguyen, R. Kongkavitool
BILATERAL COMPARISON IN HRC BETWEEN NIMT AND VMI

This bilateral comparison in HRC was conducted in order to confirm the accuracy claimed by National Institute of Metrology (Thailand) or (NIMT) and Vietnam Metrology Institute (VMI). Also, this bilateral comparison compares the difference of measurement results between lever-type machine and deadweight-type machine of two NMIs, which are NIMT and VMI, respectively.

Ki-Bok Kim, Man-Soo Kim, Jeong-Gil Park, Sangdae Lee, Ghi-Seok Kim, Hyun-Mo Jung
DETERMINATION OF APPLE FIRMNESS BY ULTRASONIC MEASUREMENT

One of the most important quality indicators for fruit is the firmness which is highly correlated to the elastic modulus. This study was conducted to evaluate the potential use of ultrasonic parameters for determination of apple firmness. Ultrasonic transmission system consisted of ultrasonic pulser, two specially fabricated ultrasonic transmitting and receiving transducers for fruit, and digital storage oscilloscope. Ultrasonic parameters such as ultrasonic wave velocity, attenuation, and peak frequency were analyzed. Firmness of apple was measured by using compression test apparatus. A multiple linear regression model describing the relationship between firmness and ultrasonic parameters was proposed.

Page 843 of 912 Results 8421 - 8430 of 9113