Volume 60, Nº 5 (2017)

The data on the type SN Ia supernovae used to confirm the accelerated “expansion of the universe” in 1998–1999 are analyzed statistically. A substantial statistical anisotropy with respect to declination is found in these data. It is shown that an examination of the relationship between the red shift of SN Ia supernovae and the photometric distance based on these data is not the most plausible hypothesis. An example of the construction of an anisotropic cosmological distance scale is given.

A comparative analysis has been done on key provisions of the current edition of the Guide to the Expression of Uncertainty in Measurement and changes thereto caused by the planned revision based on the Bayesian approach. Some possible changes of the calculation of uncertainty in measurement that are the most significant ones for practice are examined in connection with the development and introduction of the new edition of this document.

The application of parametric criteria for testing the homogeneity of variances (Bartlett, Cochran, Fisher, Hartley, Levene, Neyman–Pearson, O’Brien, Link, Newman, Bliss–Cochran–Tukey, Cadwell–Leslie–Brown, the Overall–Woodward Z-test and modified Z-test) is examined, including under conditions such that the standard assumption of normality is violated. A comparative analysis is made of the power of the criteria. The permissible level of significance is estimated for the case in which the distributions of the statistics for the applied tests are unknown.

The properties of wide-range measuring devices with linear-fractional measurement equation and constructed on the basis of linear transducers are considered. A linear-fractional equation is realized without redundancy of the quantization error over the entire range of measurements. An expression for a criterion for the generalized estimator of a wide-range device as regards precision and measurement range is obtained. The position of a linear-fractional measurement equation in the classification of methods of direct measurements is specified.

The principles of the linearization of the positional characteristics of magneto-optical displacement transducers are examined. Mathematical modeling of the positional characteristics is conducted, and results of pilot studies of prototypes of displacement transducers are presented.

Heat transfer in the contact zone of a rail and thermocouple chromel electrode was investigated. The diameter of the contact spot and angle of sharpening the electrode for reducing the measurement error with consideration of the initial temperature of the thermocouple electrode were found.

The use of morphological filtering of the profile and 3D topography of surface roughness is examined in problems of investigating the effect of morphological characteristics of a surface on its functional properties. Simple and efficient algorithms are proposed for constructing the envelopes of the profile and topography for morphological analysis of the surface. The algorithms can be integrated into software for roughness measuring devices.

A multicriteria evaluation of the degree of uniformity of the energy density distribution of laser beams based on using three criteria is proposed. It is shown that such an evaluation has a higher sensitivity to nonuniformity of the energy density distribution.

Mathematical models are proposed for evaluating the functional accuracy of an information and measuring system and the measurement channel under the influence of destabilizing factors. A comprehensive method of increasing the accuracy of the system is created that makes it possible, with permissible error, to measure the parameters of the thermophysical properties of materials: the coefficients of thermal conductivity and thermal diffusivity.

A new method is proposed for determining the magnetic susceptibility and Curie constants of various colloidal solutions in sealed glass volumes (ferrofluid cells) with an error of no more than 1.0% even with a small thickness of the layer of solution. It is shown that intensive stirring of the solution is necessary for excluding changes in the Curie constants as the cell temperature increases.

Results are presented for pilot studies of the error in measuring atmospheric brightness temperature at frequencies 20.7 and 31.4 GHz in the vicinity of water vapor emission lines. The accuracy of atmospheric brightness temperature measurements was evaluated using the water vapor radiometer at the Zelenchukskaya observatory. Measurements were made using the PNShI200 wide-aperture low-temperature noise generator, a working standard for the unit of equivalent noise temperature. The requirements for radiophysical characteristics and accuracy of reproduction of a unit of noise temperature were formulated for prospective reference wide-aperture low-temperature noise generators.

We present an experimental sample from a special radiometric complex with a calorimeter. We provide the results of an investigation of the metrological characteristics of the complex for the rating of the ionizing-radiation sources (IRSs) on the basis of the radionuclides ⁶⁰Co, ¹³⁷Cs, ¹⁹²Ir, ⁷⁵Se, ¹⁵³Gd.