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G. Linß, S.C.N. Töpfer
NOVEL METHOD FOR INLINE ESTIMATION OF PROBING UNCERTAINTY IN OPTICAL MEASUREMENT

Typically measuring points in optical coordinate metrology are considered equally at the subsequent fitting of geometric elements, for example circle. Thereby it is assumed that the related probing uncertainty does neither vary locally nor between different measuring objects. This paper outlines a novel approach for the determination of quality measures as a measure for the related probing uncertainty. The quality measures are based on the quantitative evaluation of the intensity characteristic at the edge, whose position is to be measured. Thereby five different criteria such as slope, width, form, noise and uniqueness of the edge are utilised. The overall quality measure is calculated as a weighted sum of the individual quality measures. The proposed quality measures have been applied at a number of different measuring objects. The experimental data prove the soundness of the new approach. The utilisation of the proposed quality measures results in a decrease of measuring uncertainty.

Carlos C. Dantas, Silvio B. Melo, Valdemir A. dos Santos, Eric F. de Oliveira, Francisco P. M. Simões, M. Graça dos Santos, Artur R. de Aquino
A STUDY OF UNCERTAINTY EVALUATION IN TRANSMISSION MEASUREMENT IN GAMMA RAY TOMOGRAPHY

A study of uncertainty in gamma ray transmission measurement of single beam tomography is presented. The radial density distribution of the FCC (fluidized catalytic cracking) catalyst in experimental riser is shown in measured and calculated data. Discrete models are proposed to describe data and for a better understanding of density distribution measurements. Validation procedure for the measurement models and uncertainty evaluation were carried out.

Giulio Barbato, Stefano Farné, Gianfranco Genta
MANAGEMENT OF SUBJECTIVE EVALUATIONS REPRESENTED BY ORDINAL SCALES

Common statistical methods, like arithmetic average, are, in principle, not adequate for ordinal scale evaluations, but in practice are frequently used. Specific methods are necessary, more complicated and with limits due to coarse resolution. This paper indicates some ways for overcoming resolution problems, allowing to compare specific and common analysis results. Thereafter it was possible to consider chi-square and skewness as indicators of the possibility of safely using common methods on datasets produced by non-linear metrics.

Francesco Crenna, Matteo Panero, Giovanni Battista Rossi
MEASUREMENT OF PERCEIVED SOUND INTENSITY ACCOUNTING FOR INDIVIDUAL DIFFERENCES

The measurement of quantities expressing the human response to some external stimuli is of great interest for metrology. In this paper some aspects of scale construction and measurement procedures are discussed, presenting different approaches, both direct and indirect, and focusing on the design of the panel test in order to obtain useful information for setting up the measurement scale and for the evaluation of its uncertainty. The measurement of sound intensity is considered and a case study concerning the internal noise of container trucks operating in a port is presented. The following methods are considered: - magnitude estimation; - interval estimation; - master scaling; - indirect measurements according to A–weighted sound pressure level and Zwicker’s loudness. Preliminary experimental results show the differences and criticalities among the proposed approaches, mainly due to the inherent inter and intra individual variability related to the perception itself and to its dependence on contextual factors.

Ksenia Sapozhnikova, Roald Taymanov
MEASUREMENT OF THE EMOTIONS IN MUSI? FRAGMENTS

It is shown that expected emotional response to music fragments can be measured by non-linear conversion of acoustic oscillation spectrum, selection of infrasound signals-stimuli, and identification of signal ensembles that include the sequence of not fewer than three signals-stimuli.

Johannes Pulla, Marja Mettänen, Kimmo Konkarikoski, Risto Ritala
BAYESIAN NETWORK MODEL AS AN OVERALL IMAGE QUALITY MEASUREMENT SYSTEM

This paper discusses a measuring system for overall image quality with a jury assessment as reference. The problem of combining subjective assessments and objective measurements is studied within the framework of Bayesian statistical theory and the Bayes’ network. The ideas are demonstrated with a subjective assessment test case and simulations.

Christian Eugène
MEASUREMENT OF “TOTAL VISUAL APPEARANCE”: A CIE CHALLENGE OF SOFT METROLOGY

Presentation of the main ideas of the CIE 175:2006 Report suggesting a framework for and inviting the research community to explore new measuring methods for qualifying visual appearance of manufactured products.

William P. Fisher Jr.
NEW METROLOGICAL HORIZONS: INVARIANT REFERENCE STANDARDS FOR INSTRUMENTS MEASURING HUMAN, SOCIAL, AND NATURAL CAPITAL

Invariant, additive, and separable parameters for measures of human, social, and natural capital have repeatedly proven their value and utility globally over the last 50 years. Given growing demand for comparable living capital metrics, metrological organizations should position themselves to provide the needed calibration and traceability services.

Anne-Sophie Guerra, Maurice Pillet, Jean-Luc Maire
CONTROL OF VARIABILITY FOR MAN MEASUREMENT

In a visual control, the measurement system is human. Each appraiser must control the part and judge the conformity. Consequently, the subjectivity of measure is very present and the variability therefore high. The subjectivity of this inspection is generated by two aspects: the exploration i.e. the capacity to perceive the defect by the appraiser and the evaluation i.e. the capacity to evaluate correctly the defect. So, after to realize the exploration and after to have made the evaluation, the appraiser could with more of facilities to give a reponse and so a judgement on the acceptability of the defect. The inspection must be separated into two operations: the exploration and the evaluation.

Giovanni Battista Rossi
ON SOME KEY CONCEPTS AND TERMS IN MEASUREMENT HAVING A CROSS–DISCIPLINARY IMPACT

A discussion about some key concepts and terms in measurement is proposed for promoting a fruitful dialogue among scientists of different disciplines having an experimental basis. This revision of terms requires both the examination of their current use in the involved communities and an investigation on their role in scientific theories. In the present paper, this second aspect is mainly pursued and key terms such as (measure) value, measuring system, measurement value and measurement model are discussed. Two theories of measurement are considered, deterministic and probabilistic, the former is apt to describe an ideal measurement process, the latter is able to account for uncertainty. The meaning of the measure value in a probabilistic contest is elicited and a new taxonomy of uncertainty sources is proposed. Lastly, the role of modelling in measurement is discussed.

Page 786 of 936 Results 7851 - 7860 of 9356