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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).

Akie K. Ávila, Renata M. H. Borges, Thiago de O. Araujo, Maria Cristina B. Quaresma, Fabio S. Bazilio, Lígia C. C. Oliveira
FIRST ROUND OF THE PROFICIENCY TEST SCHEME ON BRAZILIAN CACHAÇA

Cachaça is the Brazilian most popular spirit and the quality of analytical results is essential for protection of consumers and to expand the international acceptance of the product. The first round of the proficiency-testing scheme (interlaboratory study), Brazilian cachaça, was carried out between November 2004 and March 2005. The blended sample was prepared for this round containing several components, including copper, methanol and ethyl carbamate. The aim of this paper is to evaluate the laboratory performance on the determination of the copper concentration in Brazilian cachaça. Eleven laboratories reported results for copper; these results were compared to the reference value attributed by Inmetro in partnership with The Laboratory of the Government Chemist – LGC from the United Kingdom and with the consensus value. A comparison between these values was made to determine which approach could guarantee better reliability to the conclusions taken from the PT scheme. The samples used have shown good homogeneity and stability, the reference value attributed by Inmetro and LGC is SI traceable and showed to be more appropriate to be used as the conventional true value than the consensus value calculated with the participants’ results.

Kimmo Latva-Käyrä, Risto Ritala
OPTIMISING A MEASUREMENT SETUP FOR DECISION MAKING

Measurements are the key to rational decision making. Measurement information generates value, when it is applied in the decision making. An investment cost and maintenance costs are associated with each component of the measurement system. Clearly, there is – under a given set of scenarios – a measurement setup that is optimal in expected (discounted) utility. Contrary to process design, design of measurement and information systems has not been formulated as such an optimization problem, but rather been tackled intuitively. In this presentation we propose a framework for analyzing such an optimization problem. Our framework is based on that the basic mechanism of measurement is reduction of uncertainty about reality. Statistical decision theory serves as the basis for analyzing decision making. In this paper we apply the framework to a problem that is rather simple but of practical importance: how to arrange laboratory quality measurements optimally. In particular, we discuss a case in the paper making industry, in which the product quality is measured with automated quality analyzers and by laboratory measurements.

Jaime M. Ticona, Mauricio N. Frota
ECONOMIC IMPACT OF QUALITY CERTIFICATION OF INDUSTRIAL PRODUCTS ON THE BRAZILIAN DOMESTIC MARKET

Abstract: This work reviews the economics of standards, conformity assessment procedures and the trade of Brazilian industrial products. It also evaluates the associated economic impact resulted from their product certification based on international best practices. Four leading products were chosen: steel, bus coachwork, automotive tires and cement. The production time series of these products (made available by governmental agencies) were fitted by means of the multiple linear regression method. The method was successfully applied at a 5% level of significance (a probability value –p-value– lower than 0.05 guarantees the existence of non-zero polynomial coefficients).
The simulation investigated the combined economic impact of (i) the regionalization process that has led to the establishment of a common market in the South Cone (Mercosur); (ii) the exposure of the Brazilian market to international trade competition (the opening up of the Brazilian economy in the 1990’s); (iii) product certification and (iv) the monetary inflation in Brazil, in the period. Each individual impact was documented. The product certification proved to be beneficial as 15.1% growth in production of cement, 12.4 % in steel, 11% in automotive tires and 13.3 % in bus coachwork were observed.

I.Bal, W.Klonowski
APPLICATION OF NONLINEAR DYNAMICS METHODS FOR MEASURING CHARACTERISTICS OF BIOSIGNALS AND QUALITY OF MATERIALS’ SURFACES IN "SENSATION" PROJECT

We present FP6. Integrated Project SENSATION and works done by our Group on application of nonlinear dynamics for analysis of biosignals measured by new nanosensors for vigilance monitoring and for biomedical applications.

José Eduardo Manzoli, Paulo Roberto Rela, Juliana Silva Félix, Magali Monteiro
INITIAL CONCENTRATION PROFILE INFLUENCE ON MIGRATION MEASUREMENTS FROM PLASTIC PACKAGING: A SIMULATION STUDY

Migration of components from plastic packaging into foodstuffs or into medicines is a very important issue, concerning public health. Using experimental techniques, like gas chromatography-mass spectrometry, these essays measure total migration and specific migration of components from plastic packaging. This work presents an explanation and applications of a numerical technique tool for this measurement, allowing the comprehension of the diffusion process and the estimate of component migration in difficult or impractical measurements. As an application example, the non-uniform influence of initial concentration profile on the migration is presented, demonstrating the necessity of this profile determination for high quality considerations on involved metrology.

Page 836 of 907 Results 8351 - 8360 of 9067