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Walter Link, Marisa Ferraz Figueira Pereira
CALIBRATION ANGLES AT THE LEVEL OF TENTH OF SECONDS

The main purpose of this paper is to show how to reach a high precision in calibration of angle measuring devices for industry. Actually, the demand for use of optical polygons is growing, manly for calibration of CNC machines, and so their own calibration. The article will deal with basic concept and the actual technology, giving information and testing results as well as the evaluation of the uncertainty using “CIRCLE CLOSURE”.

Valery A. Granovsky, Mikhail D. Kudryavtsev
THE PLANE ANGLE CONCEPT AND ITS UNIT IN THE CONTEXT OF TRACEABILITY PROBLEM

The features of traceability structure of plane angle unit are considered. It is shown that the structure is contradicted the legalized unit, radian. It is offered to remove the contradiction by institution of the full angle (revolution) as the unit. The set of the problems demanding decisions for realization of this offer is outlined.

Alessio Carullo, Franco Ferraris, Marco Parvis
TRACEABILITY ISSUES IN DISTRIBUTED MEASURING SYSTEMS

This paper deals with the traceability-assurance problems that are faced when a distributed measuring system is employed. These problems are highlighted for different distributed-system architecture, then a set of guidelines is provided in order to correctly manage such systems from a metrological point of view. The proposed solution is based on a network-assisted calibration procedure, which requires suitable travelling standards that are sent to the nodes of a distributed system under calibration and are remotely controlled through the Internet. Two prototypes of travelling standard are also described that have been designed in order to implement the proposed calibration procedure. The first prototype can be used for the calibration of system, which require tight temporal coherence, while the second one is able to calibrate measuring nodes that monitor the chemical pollution.

Carlos J. da Silva, L. Tauhata, R.A. Barbosa, C.N.M. da Silva, M.M.O. Ramos, A. Iwahara, E.S. Da Fonseca, J.U. Delgado, Margareth M. de Araújo
ORGANIZATION OF THE IONIZING RADIATION METROLOGY IN BRAZIL

In this work it is presented the historical of the implementation and evolution of the metrology of the ionizing radiations in the Instituto de Radioproteção and Dosimetria, the formation of its technical staff, its participations in the Key-comparisons and in the metrological traceability programs developed by its metrology laboratory. It is also presented the main commitments assumed, as the adhesion to the Mutual Recognition Arrangement, MRA, the implementation and improvement of a quality system based on the ISO/IEC 17025, and the results of some quality indicators as the participations in scientific events and imeko_proceedings.

A. Iwahara, C. J. da Silva, L. Tauhata, E. M. O. Bernardes, J. U. Delgado
RADIOACTIVITY LABORATORY OF LNMRI IN THE FRAMEWORK OF MRA

This work presents the experience of the National Laboratory for Ionizing Radiation Metrology (LNMRI) in the implementation of the requirements of the Mutual Recognition Arrangement (MRA) signed by 38 National Institutes of Metrology (NMI) in 1999. The degree of equivalence of activity reported by Bureau International des Poids et Mesures (BIPM) in the Key Comparison Data Base (KCDB), the main data of a specific radionuclide listed in the Calibration and Measurement Capabilities (CMC) and the implementation of a quality system are informed.

Sergey Muravyov
RANKINGS: ARE THEY USEFUL FOR MEASUREMENT PRACTITIONERS? ARE THEY IN THE SCOPE OF METROLOGY AND MEASUREMENT SCIENCE?

Rankings are sometimes considered to be non-empirical, non-objective, low-informative and, in principle, are not worthy to be titled measurement. In our opinion, a ranking is a result of measurement on ordinal scale and is useful to the same extent as any ordinal measurement.

Franco Pavese
SOME NOTES ON REPLICATED MEASUREMENTS IN METROLOGY AND TESTING: CLASSIFICATION INTO REPEATED OR NON-REPEATED MEASUREMENTS

Replication of measurements and the combination of observations are standard and essential practices in metrology. They are done with different methods to match distinct purposes.

Alan Steele
ANALYSIS OF MEASUREMENT COMPARISONS

Can we use the probabilistic interpretation of uncertainty budgets when analyzing measurement comparisons for consistency among the participants?
Can statistical data analysis help simplify our understanding of comparison results, including the notions of a reference value, agreement, and for MRA KC only, ‘degrees of equivalence’ among the participants?

Calin Ciufudean, Camelia Petrescu, Emil Petrescu
MEASURING BOTTLENECK TIMES IN PRODUCTION LINES WITH DISCRETE EVENT SYSTEMS FORMALISMS

This paper presents a theoretic approach to measurement of the bottleneck times in production lines. The mathematical formalism utilized is characteristic for Discrete Event Systems approaches, and is about the Markov chains. Using this approach, we introduce definitions of bottlenecks, and we discuss their implications for production automation and preventative maintenance. The bottleneck of a production line is a machine that impedes the system performance in the strongest manner. The size of the buffer between the two machines is assumed to be finite. The approach is based on the sensitivity of the system production rate to machine reliability parameters.

Alessandra Licursi Maia C.da Cunha,Roberta Lourenço Ziolli, Ricardo Queiroz Aucélio
MULTIVARIATE OPTIMIZATION AIMING THE DEVELOPMENT AND VALIDATION OF A SELECTIVE ROOM-TEMPERATURE PHOSPHORIMETRIC METHOD FOR THE DETERMINATION OF CHRYSENE

In this work, a factorial design was applied for the development and validation of a solid surface roomtemperature phosphorimetric method aiming the selective determination of chrysene. Data analysis was made using several strategies: statistical experimental analysis (testing the significance of the factors using the analysis of variation, F-test and t-test), graphic method (Pareto´s chart) and the evaluation of the interactions among all variables. This procedure aimed the achievement of high accuracy of results and minimization of the time spent for optimization. A statistical program was used as a supporting tool. As the result, the experimental conditions selected for the determination of chrysene were: use of silver (I) as the selective phosphorescence inducer (applied as single 5 µL spike of Ag+ solution in the concentration range between 0,03 and 0,05 mol L-1); Basic pH of the analyte solution (NaOH 0,002 mol L-1); use of SDS as the substrate surface modifier (employed as single 5 µL of a SDS (Sodium Dodecyl Sulphate) solution between 0,25 and 0,50 mol L-1). The optimized method is highly selective towards the presence of pyrene and allowing the detection of an effective mass of chrysene in the ng range (based on the absolute limit detection, ALOD).

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