France Pavlovcic, Janez Nastran, David Nedeljkovic
Measurements are nowadays permanent attendants of scientific research, health, medical care and treatment, industrial development, safety and even global economy. All of them depend on accurate measurements and tests, and many of these fields are under the legal metrology because of their severity. How the measurement is accurate, is expressed by uncertainty, which is obtained by multiplication of standard deviations by coverage factors to increase trustfulness in the measured results. These coverage factors depend on degree of freedom, which is the function of the number of implied...
XIX IMEKO World Congress
· TC21
· 2009
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Takeshi Mizuno, Yuji Ishino, Masaya Takasaki
This paper treats a relay-feedback mass measurement system that uses a relay with dead zone and feeds back the displacement of the object. The efficacy of the proposed method has been already confirmed experimentally. In actual measurement, however, the object to be measured was guided by a spring for avoiding rotation. The effect of stiffness produced by this spring on mass estimation has not been investigated analytically. In this paper, an estimating equation including this effect is derived. The derived equation indicates that the estimated mass is smaller than the actual one when the...
XIX IMEKO World Congress
· TC3
· 2009
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Álvaro Silva Ribeiro, Maria do Céu Almeida, João Palma
Technical requirements and economical impacts of flow measurements in sewer systems are a issue concern in today's system's management. Thus, the quality of the measurements is considered to be a critical issue. Considering the complex nature of the measurand and the metrological requirements of local installations, the best available level of accuracy in measurement results should be sought. Therefore, both the knowledge of the measurand estimates and measurement of uncertainties are required for achieving robust results. Within this context, the quality of measurement results depends on...
XIX IMEKO World Congress
· TC9
· 2009
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Ferran Reverter, Goran Horak, Vedran Bilas, Manel Gasulla
This paper proposes a low-cost technique to compensate for the temperature dependence of piezoresistive pressure sensors configured in a Wheatstone bridge. The sensor is treated as a resistive circuit and three equivalent resistances are measured by setting appropriately the bridge terminals. One of these equivalent resistances depends on temperature but not on pressure and, hence, it can be used to compensate for the temperature dependence of the output parameter. In such a way, neither data of a previous temperature calibration nor additional components are required to compensate for the...
XIX IMEKO World Congress
· TC16
· 2009
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Paul Clarkson, Paul Wright
The accurate measurement of many power quality parameters using digital sampling techniques relies on synchronisation between the sampling system and the signal under analysis. If synchronisation is not available measurement errors result due to the difference in frequency of the digitised signal and that expected and based on the sampling clock of the measurement system. A method is presented of correcting for this lack of synchronisation. This method relies on a time domain interpolation technique to modify the sampling rate of the captured signal in software. In order to find the correct...
XIX IMEKO World Congress
· TC4
· 2009
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Takashi Takuma, Shinji Yabushita, Takeshi Kawajiri, Kana Yanogawa, Takaki Harada, Kazuya Yamamoto, Ichirou Ishimaru
We proposed the imaging-type 2-D Fourier spectroscopy that is the phase-shift interferometry between the objective lights. The proposed method can measure the 2-D spectral image on the focal plane. We construct the proposed method by the infrared radiation optical system to try to apply for the noninvasive measurement of the blood glucose level. In this report, we discuss about the spectroscopy method to measure the vessel area of the proximal skin surface that is little affected by the diffusion cased by the biological membrane. The proposed method is constructed with Fourier spectroscopy...
XIX IMEKO World Congress
· TC13
· 2009
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Marek Zielinski, Marcin Kowalski, Dariusz Chaberski, Slawomir Grzelak
This paper describes the new method of time-interval-error (TIE) estimation and prediction. This method is very useful for standard clocks characterization and can be applied in high precision measurement and telecommunication systems with high resolution of the time-base. TIE can be easily and fast calculated using only two parameters obtained during calibration process. Moreover, it is very simple method for clocks comparison and can be applied in time-interval measuring systems (TIMS) for calibration or TIE calculation. This method allows to calculate an accumulated jitter and TIE as a...
XIX IMEKO World Congress
· TC4
· 2009
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Filip Dvorak, Jan Maschke, Cestmir Vlcek
This paper deals with the measurement of SOP (State of Polarization) of polarization preserving fiber and its time stability. Linear or circular polarized light was launched into the input of "bow-tie" and "Panda" fibers respectively and the resultant output intensity for different positions of output polarizer was measured. The resultant values have been interpreted on the Poincaré sphere by means of the MATLAB® environment. Typical curves of time fluctuation of ellipticity and ellipse azimuth of the output SOP are presented, too.
XIX IMEKO World Congress
· TC2
· 2009
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José Manzoli, Jorge Pirolla, Eduardo Moura, Carlos Zeituni, João Moura, Maria Elisa Chuery Martins Rostelatto
Radiation sealed sources have an emission that could be studied by theirs isodose surfaces. The intersection of a plan with such a surfaces is described by the dose rate contour curves. It is very common to assume that these surfaces have rotational symmetry around the longitudinal axis, and so, the contour curves have mirror symmetries. Here it is shown, by a computational simulation, that if the radioactive material inside de sealed vessel is not homogeneous, the uncertainty in dose rate measurements could achieve high values. This uncertainty value is exemplified in a iodine-125 seed...
XIX IMEKO World Congress
· TC13
· 2009
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Dragan Kovacevic, Jelena Lukic, Dragana Naumovic-Vukovic, Slobodan Skundric
Power transformers are the most complex, important and critical components of the transition and distribution power systems. Insulation system is the key component of life extension, better availability and higher reliability of a transformer. In order to achieve both decreasing operational cost and reliable service condition-based maintenance is needed. Monitoring and diagnostic methods and techniques, for insulation condition assessment of power transformers, are described. Data base and knowledge rules diagnostic management system, in internet oriented environment, is outlined.
XIX IMEKO World Congress
· TC10
· 2009
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