Publications (16)12.85 Total impact
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Article: Comparison EUROMET.EM-K8 of DC voltage ratio: results
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ABSTRACT: A regional key comparison of dc voltage ratio has been carried out in Europe. The method to evaluate the comparison reference value, the resulting degrees of equivalence for the voltage ratios 1000 V/10 V and 100 V/10 V and the link to the corresponding worldwide key comparison CCEM-K8 are reported.IEEE Transactions on Instrumentation and Measurement 05/2005; · 1.21 Impact Factor -
Article: The IEN CCC bridge to scale the quantized Hall resistance to 1-Ω standards
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ABSTRACT: A resistance bridge based on a cryogenic current comparator has been built at the Istituto Elettrotecnico Nazionale "G. Ferraris" (IEN). The use of this bridge simplifies the scaling down from the quantized Hall resistance to decadic standard resistors, at the same time reducing the measurement uncertainty. The bridge is described and the result of a comparison at the level of 100 Ω, with the traditional scaling method used at IEN is reported. The two methods agree well within their uncertainties, for which detailed uncertainty budgets are given.IEEE Transactions on Instrumentation and Measurement 05/2005; · 1.21 Impact Factor -
Article: Report on Key Comparison EUROMET.EM-K8.1 (DC voltage ratio)
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ABSTRACT: Comparison EUROMET.EM-K8.1 was a follow-up to comparison EUROMET.EM-K8 and was organized for those participants in EUROMET.EM-K8 willing to improve their results. It had the same pilot laboratory and the same protocol as the other K8 comparisons and its travelling standard was the same resistive divider already used in comparison CCEM-K8. On this divider the measurements of voltage ratios 1000 V/10 V and 100 V/10 V were mandatory; the measurements of other ratios were optional. Four laboratories, plus the pilot, participated, but one of them withdrew from the comparison before the Draft A report was released. The degrees of equivalence with respect to the Key Comparison Reference Value, which is the reference value of comparison CCEM-K8, were evaluated by using the results of the pilot laboratory to link the two comparisons. With the exception of one result, which is on the boundary of the 95% confidence interval, the agreement of the other results with the reference value is excellent. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the Mutual Recognition Arrangement (MRA).Metrologia 04/2005; 42(1A):01003. · 1.75 Impact Factor -
Article: Report on Key Comparison CCEM-K8.1 (DC voltage ratio)
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ABSTRACT: Comparison CCEM-K8.1 is a follow-up to comparison CCEM-K8 and was organized for those participants in CCEM-K8 willing to improve their results. The same travelling standard as in CCEM-K8, a Datron 4902S DC resistive divider, was used, but the trimmers of the divider were adjusted in order to change the deviation of the divider's ratios from nominal value. The comparison protocol was the same as for CCEM-K8 and requested the measurement of voltage ratios 1000 V/10 V and 100 V/10 V, the measurement of other ratios being optional. Two laboratories participated, but one of them withdrew before the draft A report was released. In the comparison's final report the results of the other laboratory, CEM from Spain, are linked to those of comparison CCEM-K8 through the measurements of IEN, which was the pilot laboratory of both comparisons. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the Mutual Recognition Arrangement (MRA).Metrologia 06/2004; 41(1A):01003. · 1.75 Impact Factor -
Article: Report on Key Comparison EUROMET.EM-K8 (DC voltage ratio)
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ABSTRACT: The purpose of the regional comparison EUROMET.EM-K8 was to compare the scaling capabilities up to 1000 V DC of the European national metrology institutes, thus extending to Europe the evaluation of equivalence of voltage ratio measurements obtained by the comparison CCEM-K8. Twenty laboratories participated, with the Istituto Elettrotecnico Nazionale Galileo Ferraris (Torino, Italy) acting as pilot laboratory. The circulation of the travelling standard, a resistive voltage divider, started in July 1998 and ended in January 2002. The technical protocol requested the measurement of voltage ratios 1000 V/10 V and 100 V/10 V, the measurement of other ratios being optional. Nineteen laboratories reported measurements of the mandatory ratios. For these ratios, the measurement methods used are described and the process to evaluate the comparison reference value and the degrees of equivalence is reported in detail. The relative uncertainty of the comparison, given by the combination of the uncertainty of the reference value and the instability of the transfer standard, was about 0.26×10-6 for ratio 1000 V/10 V and about 0.16×10-6 for ratio 100 V/10 V, at 95% level of confidence. The results for the optional ratios are reported in an appendix. With some exceptions, the agreement between the results is satisfactory. Main text. To reach the main text of this paper, click on Final Report. Note that this text is that which appears in Appendix B of the BIPM key comparison database kcdb.bipm.org/. The final report has been peer-reviewed and approved for publication by the CCEM, according to the provisions of the Mutual Recognition Arrangement (MRA).Metrologia 01/2004; 41(1A):01001. · 1.75 Impact Factor -
Conference Proceeding: Modular system for the calibration of capacitance standards based on the quantum Hall Effect
NCSL 2003 International Workshop and Symposium, Tampa, USA; 08/2003 -
Article: Comparison CCEM-K8 of DC voltage ratio: results
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ABSTRACT: Fifteen National Metrology Institutes have participated in DC voltage ratio comparison CCEM-K8. The method followed to normalize the participants' results, the calculation of the key comparison reference values and the comparison results are reported for the two mandatory ratios of the comparison, 1000 V/10 V and 100 V/10 V.IEEE Transactions on Instrumentation and Measurement 05/2003; · 1.21 Impact Factor -
Article: The European ACQHE project: modular system for the calibration of capacitance standards based on the quantum Hall effect
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ABSTRACT: A project funded by the European Commission which started in 1998 has been completed. The aim of this project was to establish a measurement system that allows the calibration of standard capacitors in terms of R<sub>K-90</sub>. The whole system comprises quantum Hall samples, an automated modular bridge system, and devices to calibrate and characterize the set-up. The uncertainty for the calibration of a 10-pF capacitor is about one part in 10<sup>7</sup>.IEEE Transactions on Instrumentation and Measurement 04/2003; 52(2):563 - 568. · 1.21 Impact Factor -
Article: Final report on key comparison CCEM-K8 (dc voltage ratio)
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ABSTRACT: The purpose of CIPM comparison CCEM-K8 was to compare the scaling capabilities up to 1000 V dc of national metrology institutes. Fifteen institutes participated, with the Istituto Elettrotecnico Nazionale Galileo Ferraris (Turin, Italy) acting as pilot laboratory. Circulation of the travelling standard, a resistive voltage divider, started in October 1998 and ended in June 2001. The technical protocol requested the measurement of voltage ratios 1000 V/10 V and 100 V/10 V, the measurement of other ratios being optional. For the mandatory ratios, the measurement methods used by the participants are described and the evaluation of the key comparison reference value and the degrees of equivalence is reported in detail. For these ratios, the relative uncertainty of the comparison, given by the combination of the uncertainty of the reference value and the instability of the transfer standard, was about 0.23×10-6 at 95% level of confidence. Results for the supplementary ratios are reported in an appendix. With certain exceptions, agreement between the results is satisfactory; in some cases the measurement uncertainty was underestimated.Metrologia 01/2003; 40(1A):01001. · 1.75 Impact Factor -
Conference Proceeding: Comparison CCEM-K8: final evaluation of the travelling standard
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ABSTRACT: Circulation of the travelling standard for international comparison CCEM-K8 on DC voltage ratio was completed in June 2001. Awaiting the conclusion of the process leading to the agreed final report, the final evaluation of the behavior of the standard is given.Precision Electromagnetic Measurements, 2002. Conference Digest 2002 Conference on; 02/2002 -
Article: Noise spectroscopy in the breakdown of the IQHE
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ABSTRACT: The noise spectrum of the magnetoresistivity in the breakdown of the Integral Quantum Hall Effect (IQHE) at high currents is studied in wide high-quality GaAs/AlGaAs heterostructures on thei=2 Hall plateau, in particular for values of current and/or magnetic field at which pronounced steps and striking temporal patterns showing switching between different levels are observed. The noise spectra obtained from data which display switching are compared with the spectra obtained in the absence of switching. By an analysis based on time series simulation, Lorentzian noise components are separated and found to have similar characteristics in both types of data.Il Nuovo Cimento D 10/1996; 18(11):1295-1306. -
Conference Proceeding: The representation of the ohm using the quantum Hall effect at IEN
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ABSTRACT: A method to measure the quantized Hall resistance (QHR) in terms of the Istituto Elettrotecnico Nazionale (IEN), Italy, reference standard is described. Measurements showing the independence of QHR from the experimental conditions are reported. A preliminary evaluation of the difference between Ω<sub>IEN</sub> and the new quantum-Hall-based standard is givenPrecision Electromagnetic Measurements, 1990. CPEM '90 Digest., Conference on; 07/1990 -
Article: Electrolytic conductivity: a reference system for aqueous solutions.
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ABSTRACT: To establish a system for the measurement of electrolytic conductivity in aqueous solutions with traceability to the SI, a cell has been developed with a removable central section providing an accurate determination of the geometrical constant. As the concentration unit mass/mass, based and referred to the amount of substance in the SI, is recommended by international organisations, 0.1 molal KCl samples have been prepared and analysed. Results over a temperature range from 20 degrees C to 35 degrees C are presented. The main sources of error have been estimated and relative uncertainty has been assessed to remain at the level of 0.6%. Satisfactory agreement is observed when the results are compared with the reference values available from literature.Annali di Chimica 91(7-8):409-14. · 0.99 Impact Factor -
Conference Proceeding: Feasibility study on an indirect quantum standard of the ampere
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ABSTRACT: An indirect quantum standard of current, based on the simultaneous use of the Josephson and quantum Hall effects, may help to achieve interesting results in fundamental experiments involving the determination of the elementary electrical charge e and of the Josephson and von Klitzing constants. A feasibility study of such a measuring system is proposedPrecision Electromagnetic Measurements, 1994. Digest., 1994 Conference on; -
Conference Proceeding: Analysis of the breakdown of the IQHE in wide GaAs/AlGaAsheterostructures
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ABSTRACT: The breakdown of the integral quantum Hall effect (IQHE) at high current is studied in wide high quality GaAs/AlGaAs heterostructures on the i=2 and i=4 Hall plateaux. Pronounced steps in the longitudinal resistance are observed with rich time structures, which are analyzed with different techniquesPrecision Electromagnetic Measurements, 1994. Digest., 1994 Conference on; -
Article: Comparison CCEM-K8 of DC voltage ratio: results
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ABSTRACT: Copyright: 2003 IEEE This article discusses the outcome of DC voltage ratio comparison CCEM-K8 that was participated by fifteen National Metrology Institutes. The need for a key comparison of DC voltage ratio was recognized by the Comite’ International d’electricite’ et Magnetisme (CCEM) at its 20th meeting in June 1995. Its purpose was to compare the scaling capabilities in DC voltage of the National Metrology Institutes (NMI) up to 1000v. After preliminary studies carried out at IEN [1], a Daltron 4902s voltage divider(s/n20.335) as the traveling standard was adopted to normalize the participants’ results, the calculation of the key comparison reference values and the comparison results were reported for the two mandatory ratios of the comparison, 1000v/10v and 100v/ 10v. More detailed informational and the results for the optional measurement can be found in the comparison final report [3].
