IMEKO Event Proceedings

Page 1 of 748 Results 1 - 10 of 7479

M. P. van der Beek, R. van den Brink
'GAS OIL PISTON PROVER', PRIMARY REFERENCE VALUES FOR (HIGH- PRESSURE) GAS-VOLUME, RESULTS

The paper describes the design, measurement results and uncertainty analyses of the hydraulic driven piston-prover system which is in operation at VSL since 2008. The 12 meter long, 0.6 m bore piston-prover is used for the realization of Reference Values for Gas-Volume at pressures between 1 and 65 bar(a) and ‘any’ type of Gas. The principle is based on the displacement of a piston acting as a Gas-Oil separator. The standard has a flow-rate range from 5 to 230 m3/h. The system is designed to calibrate reference meters. The Calibration and Measurement Capability (CMC) of the system is proven smaller than 0.1% (k = 2). The paper also explains the coherence between the Gas-Oil Piston-Prover and other traceability generators and ‘flow rate bootstrapper systems’.

G. Barbato, G. Brondino, M. Galetto, G. Vicario
'ZERO POINT' IN THE EVALUATION OF MARTENS HARDNESS UNCERTAINTY

The Instrumented Indentation Test is based on simultaneous recording of force and indentation depth, obtained during test cycle. The force-depth curve, describing the indentation pattern, is typically formed by two parts having the “zero-point” in common, i.e. the first contact point between the indenter and the surface of test piece. The zero-point determination is a crucial aspect for Martens Hardness evaluation, so that relevant ISO standard suggests to estimate it by extrapolation of polynomial fitted functions. In this paper a new model, based on a segmented function, is proposed. This approach implies the use of maximum likelihood estimator for parameters determination. The corresponding uncertainty is provided through the covariance matrix of the regression model.

Dilhermando Augusto de Mello, Luciana A. Almeida Carvalho
"IT IS NOT FORBIDDEN TO DREAM… NOR TO COUNT TALES" METROLOGY EDUCATION FOR THE YOUTH

XVIII IMEKO World Congress presents the paper METROLOGY EDUCATION FOR THE YOUTH. The work addresses among one forms playful to present the metrology fundamentals and the main scientists who contributed with their discoveries, research and measurements, throughout the evolution of the human being and the technology.

M. P. van der Beek, I. J. Landheer
"NMi TraSys", THE ULTIMATE CARRIER & MULTIPLIER FOR THE UNIT OF VOLUME FOR HIGH-PRESSURE NATURAL GAS

The paper describes the newly developed "NMi TraSys" - NMi Traceability System. This travelling carrier & multiplier of traceability has been realized to embody a significant part of the Dutch National traceability-chain for high-pressure gas-flow measurements. The number of contributions of uncertainty as well as their values, due to "copy-losses" and "installation-effects" during the traditional transfer of traceability from one facility to another, are decreased.
First results are presented about observed repeatability and reproducibility, uncertainties and consistency checks. The device will include in time, reference values of three different independently realized primary standards (viz. DDD - Dynamic Displacement Device, GOPP – Gas-Oil Piston-Prover and NMi TraSys itself). With internal harmonization processes at NMi VSL with "input" reference values from the three other primary standards, viz. DDD-conventional, DDD-extended pressure level and GOPP, the aim of 0,1% uncertainty at 4.000 m³ / h and p = 60 bar is within reach. This will improve the uncertainty as well as the stability of the Dutch National reference values considerably.
NMi TraSys will be used as a set of Travelling Reference Meters, creating an efficient availability of stable and validated Harmonized Reference Values for high-pressure gas-flow.

Iulian Ilies, Mihai Munteanu, Radu A. Munteanu
“Intelligent” Controller Algorithm for Load Distribution Enhancement of IEEE 802.11 INTER-WLAN Traffic

This paper analyses the possibility to have a dedicated signaling channel for triggering load balancing mechanism based on relevant specific traffic parameters analysis (e.g. throughput, EIRP, Antenna Gain). Compared to classic algorithms, the signaling channel brings the advantage of distributed “effort” between Access Points and Controllers. Experiments were performed with Matlab and the results show the network performance enhancement in terms of Load and Throughput. The proposed signaling channel shows effectiveness of the load distribution enhancing also the network performance.

Komyo Kariya, Shigeru Takayama
“MEASUREMENT SCIENCE” AND EDUCATION TO CULTIVATE SCIENTIFIC BASIC KNOWLEDGE OF PEOPLE

We had already expressed the importance of “Measurement Science” .on the education to rise up the scientific sense for the people live in the society carried on natural science, technique and information. It is the liberty to apply how “Science” to the Education, an answer is in this paper. And we had reported the contents by some papers. This paper suggests the usefulness of application of “Measurement Science” for the stage 1 and stage 2 education (Compulsory Education) and the stage 3 education (Semi-Compulsory Education), when classify National Education in 5 stages.

A. Sabatini, A. Moschitta, P. Carbone
ΣΔ-BASED REMOVAL OF UNWANTED SPECTRAL COMPONENTS FOR SINEWAVE SYNTHESIS

This paper addresses the generation of spectrally pure sinewaves by combining the feedback structure of a ΣΔ loop with digital cancellation of unwanted spectral components in the output signal. In particular, the non-linearities of the in-loop Digital to Analog Converter (DAC) are compensated by applying a digital pre-distortion to the DAC input, and the feedback architecture is used to enhance the performance of the all digital estimation and cancellation algorithm.

Elisa Bonacini, Davide Tanasi
#iziTRAVELSicilia: a participatory storytelling project

The aim of this paper is to present the participatory project "Sicilia Beni Culturali" on the izi.TRAVEL platform, launched in May 2016 and well known on social media as #iziTRAVELSicilia. Recognized as a facilitator of best practice digital promotion and valorization through storytelling and crowdsourcing culture, it has already involved thousands of people. With over 150 audio guides produced on the platform in just over a year, #iziTRAVELSicilia has become a real model of participation in co-creation of cultural values, by practicing the principles set out by the Faro Convention. In this paper we briefly present the project and the example of the Roman Villa of Durrueli and how this platform was and can be furtherused for the dissemination of existing 3D models and for new 3D models, such as those made by the USF - CVAST virtualization project in Sicily.

Torben R. Licht, Sven Erik Salboel
0 Hz AND LOW FREQUENCY CALIBRATION OF LOW FREQUENCY REFERENCE ACCELEROMETERS

During the last decade more and more interest has been found in making low frequency vibration measurements. One area that has driven this is the earthquake studies, but here accuracy is not a focus point. However when we start to look at large structures like wind turbines, large aircrafts with 60 to 80 m wingspan, bridges and 400 to 500 m towers the accuracy becomes vital. These large structures have vibration modes in the range 0.3 to 1 Hz.
The method for Primary vibration calibration by laser interferometry using quadrature outputs described in ISO 16063-11 can be extended down to 0.1 Hz today thus giving the foundation for accurate measurements in the low frequency (LF) range.
It is however desirable to link these results that are obtained at very low vibration levels and frequencies to measurements at 0 Hz with constant acceleration of about 9.8 m/s².
This method is basically described in ISO 5347-5 (to be revised as ISO16063-16) but a detailed description of uncertainty budgets is not given.
Recently the Danish Primary Laboratory of Acoustics (DPLA) participated in the first international comparison covering the LF range of vibration, and in that context we decided to make a 0 Hz calibration with relatively simple means but exploiting the fact that the local Gravity today can be determined by an uncertainty of about 10-8.
By using a transfer technique and without utilising the full potential we could make an uncertainty budget with an expanded uncertainty of about 0.04% on a servoaccelerometer calibration, where one of the main contributions turned out to be thermal drift.
The experience we got during this calibration and the uncertainty budget created will be presented.

Pier Paolo Capra, Flavio Galliana, Marco Lanzillotti
1 %Omega;–10 k%Omega; High Precision Resistance Setup to calibrate Multifunction Electrical instruments

A temperature controlled 1 %Omega;–10 k%Omega; Standard resistors setup was developed at National Institute of Metrological Research, (INRIM). The aim of this realization was the involvement of the setup resistors in the traceability transfer process to high accuracy multifunction electrical instruments used in Secondary Electrical Calibration Laboratories or even their use as primary Standards in high level Laboratories or Institutes. The 1 %Omega;–10 k%Omega; Standards are formed respectively by two 10 %Omega; and 100 k%Omega; parallel connected resistors nets inserted in a temperature controlled aluminium box. Construction details, temperature and power coefficients, stability data and preliminary mid-term use uncertainty budgets of the two setup Standards are given. Their first short time (2 h) stability were on the order of few parts of 10–8. A test to calibrate a multifunction calibrator gave satisfactory results.

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