Directions of development and design for the unit of gravity acceleration, units of vertical and horizontal gravitational gradients, units for the plumb line deviation, and unit of gravitational potential are considered, based on the analysis of modern achievements in the design of gravimetry tools.

Methods for estimating the parameters of the formula for the optimal discretization of the range of variation in the probability density of a two-dimensional random variable are considered. The properties of the proposed methods are investigated and the conditions for their competence are defined.

Analytical expressions are derived for the assessment of the risks of the manufacturer and customer, when inspecting measuring instruments errors in one or more points. It is suggested that the conclusion oh these expressions should be included in the current normative documents.

Algorithms and technologies for replacing unmeasurable samples of the noise with their approximate equivalent values are proposed; the possibility of using them to increase the reliability of the results of spectral analysis of the noisy signal and to determine the estimates of the spectral characteristics of the noise in monitoring the beginning of changes in the technical condition of control objects is shown.

Distribution laws and confidence limits are determined for a compiex measurement channel (MC) with n simple mcs. calculations are made assuming that the error of every simpie mc has a uniform distribution in the section of [-d, +d]. It is shown that the values of calculated for the composite distribution of the error of a complex MC and for the normal distribution with the same value of dispersion are close to each other. With a confidence probability of P=0,95 the difference in the calculated values does not exceed 3 %.

The paper proposes a conceptual model of a data acquisition system based on distributed smart geosensor networks. The tasks that were to be accomplished through the development of a conceptual model: to provide easy scalability of the system; to provide a system performance sufficient for processing of the spatio-temporal data streams coming from the geosensor network in real time; to provide the possibility of component development of the system. The proposed conceptual model provides a high level of interoperability between the allocated logical blocks of the system (compatibility at both the semantic level and the process level), the possibility of implementing its logical blocks as separate components, and the ability to process spatio-temporal data streams of high intensity.

The reset automatic tool for contactless control of external thread based on optical spatial filtering method is described. The automatic tool allows to carry out the complex control of fine threads of boxy parts with soft coating.

А scheme for measuring phase noise using a РМ-fiber based Mach-Zehnder interferometer is proposed. Two interference signals from orthogonally polarized waves are formed in the scheme, which subsequently are separated by a poiarization demultiplexer. This allows to avoid the influence of external noise on the measurement result. An algorithm is described for calculating phase noise and the effect of temperature instability is estimated. In order to assess the operability of the scheme and the signal processing algorithm, the comparison is made of the calculated values of the phase noise and the values specified in the simulation.

The review of research results of frequency instability of the hydrogen frequency standard output signal is presented. The reasons for increasing instability in the measurement interval more then 1000 c are considered. Dependences on ambient temperature and geomagnetic field are investigated. The procedure of the frequency drift compensation by using a periodic correction is presented.

The density correction associated with the working liquid compressibility of laser interferometric oil manometer (LIMM) functioning as a component of State Primary Pressure Standard GET 101-2011 was defined by the use of specially developed interferometric low pressure liquid piezometer. It was shown that in the LIMM working conditions the compressibility effect almost completely compensates the working liquid density changes due to liquid outgassing measured in PTB, Germany. So the reliability of GET 101-2011 pressure measurements in the range of 10^-1-10³ Pa was confirmed.

The results of the theoretical and experimental investigations of the surface tension measurement method based on deformation of a tested liquid by a gas jet are presented. The choice of the parameters of the aerodynamic impingement and the predetermined value of the height of cavity on the liquid surface was made on the base of formulated criteria. Due to significant influence of liquid density on the results of measurement the method is recommended for the determination of the suface pressure of surface active agents.

Тhe possibility of the realization of tin fixed point of the International Temperature Scale 1990 in a miniature cell using together with handheld temperature calibrator has been investigated with the purpose of rise of operative calibration accuracy of small-size precision platinum resistance thermometer up to echelon of accuracy of second class reference resistance thermometers. It is shown that it is impossible to use the melting curves of tin with a purity of 99,999% in a miniature cell for this purpose. The decrease of the liquidus temperature of domestic commercial tin due to the impurities influence is determined. The optimal regimes of the reproducibility of tin freezing diagrams acceptable for developed calibration methods are detected and that diagram characteristics are studied.

Paper shows design of experimental software-hardware setup for measuring of electric resistance of metal conductors at high temperatures. The designs of separate elements, providing stable work and high accuracy of the measurements results are offered. Measurement of electrical resistance of iron ARMCO is conducted for testing purpose.

А hybrid frequency synthesizer is presented with images of the fundamental frequency of direct digital synthesizer used to improve noise characteristics. It is shown that the developed synthesizer has a simple architecture and can generate a wide range of output frequencies with a small step size adjustment. A mathematical modelling of noise characteristics of the synthesizer is carried out and a comparison with the phase noise level of heterodynes of modern spectrum analyzers is made.

The method of control and the algorithm of catalytic gas-sensitive sensor operation for decreasing measurement errors and an increasing sensor life were considered.