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Yury Skripnik, Aleksandr Krasuk, Vyacheslav Manoylov, Sergey Peregudov, Aleksey Yanenko
INCREASED ACCURACY OF MEASUREMENT OF HIGH-SENSITIVITY MM-RANGE RADIOMETRIC EQUIPMENT INTENDED FOR MEDICAL-BIOLOGICAL APPLICATION

The paper considers the methods of improving the accuracy of measurements of low-intensity electro-magnetic radiation of the bio-objects in mm-range carried out with the use of high-sensitivity radiometric equipment with the reference noise generator included into its structure. The main sources of uncertainty of measurement are deter-mined. It is shown that with the help of a reference noise generator having the power comparable with radiation power of bio-objects, it is possible to decrease essentially the uncertainty of measurement and to register accurately the peculiarities of radiation spectrum of the living objects.

Vladik Kreinovich, Gennady N. Solopchenko, Scott A. Ferson, Lev Ginzburg, Richard Alo
PROBABILITIES, INTERVALS, WHAT NEXT? EXTENSION OF INTERVAL COMPUTATIONS TO SITUATIONS WITH PARTIAL INFORMATION ABOUT PROBABILITIES

In many real-life situations, we are interested in the value of a physical quantity y that is difficult or impossible to measure directly. To estimate y, we find some easier-to-measure quantities x1,..., xn which are related to y by a known relation y = f(x1,..., xn). Measurements are never 100% accurate; hence, the measured values xi,m are different from xi, and the resulting estimate ym = f(x1,m,..., xn,m) is different from the desired value y = f(x1,..., xn). How different?
Traditional engineering to error estimation in data processing assumes that we know the probabilities of different measurement error Δxi (def) = xi,m - xi.
In many practical situations, we only know the upper bound Δi for this error; hence, after the measurement, the only information that we have about xi is that it belongs to the interval xi (def) = [xi,m - Δi, xi,m + Δi]. In this case, it is important to find the range y of all possible values of y = f(x1,..., xn) when xi ∈ xn.
We start with a brief overview of the corresponding interval computation problems. We then discuss what to do when, in addition to the upper bounds Δi, we have some partial information about the probabilities of different values of Δxi.

A. S. Ribeiro, J. A. Sousa, M. P. Castro
SOME REMARKS ON THE USE OF U-SHAPE PROBABILITY DISTRIBUTION FUNCTIONS IN MONTE CARLO SIMULATION

Although Monte Carlo simulation (MCS) has been applied to the calculation of measurement uncertainties in metrology problems, its use has generally been restricted to cases where the distributions assigned to the pdf’s of the input quantities are the more common Gaussian, rectangular and triangular distributions. However, cases exist where the distributions of the input quantities are more complex, such as U-shape (e.g. electrical metrology), and combinations of this and the above and other distributions. This study will establish procedures for sampling from and using such distributions and develop appropriate algorithms.
In particular, this paper will concentrate on approaches that are free from the assumptions inherent in the GUM-based procedures that are conventionally used. Those procedures are at the moment “taken as read” by many laboratories when, in fact, the conditions for their application do not necessarily apply (e.g. normality of distributions involved, input quantities uncorrelated). Thus, simulations will be carried out based on a U-shape probability distribution function, to investigate the validity of the GUM approach using the MCS technique as the validation tool.

Maurice G. Cox, Annarita Lazzari
MODELLING AND UNCERTAINTY OF HIGH-ACCURACY ROUNDNESS MEASUREMENT

High-accuracy roundness measurements of a component made with an instrument having a precision rotary stage are considered. The measurements comprise a superimposition of the component form deviation and the instrument spindle deviation, the latter being a consequence of the imperfect but highly repeatable rotation of the sensor. These effects need to be separated in order to determine the departure from roundness of the component, and also of the spindle deviation. Separation is possible by using the rotary stage to take several sets of measurements, corresponding to different angular positions of the component with respect to the rotary stage, which introduces phase differences relative to these effects. The evaluation of the uncertainty associated with the departures from roundness is the main concern. When the measurements are uncorrelated, the evaluation provides specific formulae for the uncertainty. For the instrument of concern, the presence of serial correlations in the measurements means that the uncertainties so evaluated would be too small. An approach based on the use of bootstrap re-sampling is given that permits the correlation effects to be taken into account. Results are provided for comparison with those obtained based on the assumption that the measurements are uncorrelated.

Filippo Attivissimo, Nicola Giaquinto, Mario Savino
UNCERTAINTY EVALUATION IN DITHERED A/D CONVERTERS

In this paper formulae for evaluating the uncertainty of measurements (direct and indirect) performed by means of an ADC-based device are presented. The complex technique of dithering is used to reduce the effect of noise and to increase the ADC resolution. The authors discuss a way of writing and interpreting the uncertainty specifications of ADCs.

Edi Kulderknup
UNCERTAINTY OF OCCUPATIONAL HEALTH MEASUREMENTS

Occupational health measurements have considerable importance to safeguard the health of personnel in the working environment. Assurance of healthy conditions is prescribed in legal acts and if those requirements are not fulfilled can entrepreneur have considerable economical losses trough the authorities sanctions and charges for the damaged personnel. To have correct conformity estimation against legal limit values evaluator must have the reliable result of measurement and the truthful uncertainty estimation. Uncertainty estimation of occupational health measurements have some special particularities. Sound way to assure the best measurement capability is the interlaboratory comparison.

Jacek Nalepa
CORRECTION OF DYNAMIC ERROR BY THE ""BLIND” METHOD. A DIFFERENTIAL ALGORITHM SIMULATION STUDY

The „blind” method of correction algorithm uses the results of two parallel measurement channels and consists of two stages. The first stage is identification of the dynamic properties of the measurement channels, the second one is the correction itself. A differential algorithm of identification based on minimisation of the difference between the results of both measurement channels connected with correctors. The paper presents the results of the simulation study on the differential algorithm of the correction of the dynamic error for measurement channels modelled as first- and second-order system. A simulation study similar to that presented in the paper, can be an effective instrument to determine conditions for the practical applicability of the dynamic error correction by the „blind” method for a particular measurement channels.

Roberto Lojacono
THE CALIPER RULE AS A PARTICULAR CASE OF RESIDUE NUMBER SYSTEM ARITHMETIC

The caliper rule is generally considered as a particular tool, which renders a scale more readable. This paper shows that this rule can be viewed, from a theoretical point of view, as the way to realize a small “virtual unity”. This virtual unity can be used in determining the conversion between different units and can represent the basic unity of a particular measurement system, which gives the results of the measurements directly in RNS arithmetic.

Komyo Kariya, Shigeru Takayama
FOUR EXPRESSIONS OF FUNDAMENTAL STRUCTURE OF MEASUREMENT SCIENCE

This paper is a discussion of a simple structure of “MEASUREMENT SCIENCE” to use on education process to rise up the scientific knowledge of all people who live in science and technology and information oriented society. An act of measure is a fundamental act of a man and people take action to getting information and knowledge by the act, and the people live a life in society, perform the social activity and contribute to the development of society. At the age of science, technology and information oriented society, a science that all people able to learn at each education stage according to each level is wanted. When an act of measure is arranged systematically as the fundamental act of human action and discuss about its social role, “MEASUREMENT SCIENCE” becomes just very appropriate science. In this paper, a structure of MEASUREMENT SCIENCE is arranged by the four definition-functions.

Vadim G. Knorring
MEASUREMENT AS A COGNITIVE PROCESS

Two principles for arranging existing and possible theories of measurement into a system are proposed. The second (functional) principle seems to be more useful for engineering education.

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