Velocity is an important parameter for fluid flow characteristics in profile logging. Particle tracking velocimetry (PTV) technology is often used to study the flow characteristics of oil wells with low flow velocity and high water cut, and the key to PTV technology is particle matching. The existing particle matching algorithms of PTV technology do not meet the matching demands of oil drops in the

This paper is focused on the nonlinear state estimation problem with finite-step correlated noises and packet loss. Firstly, by using the projection theorem repeatedly, the mean and covariance of process noise and measurement noise in the condition of measurements before the current epoch are calculated. Then, based on the Gaussian approximation recursive filter (GASF) and the prediction compensation

The paper presents a matrix approach to the propagation of uncertainties in the realization of the ITS-90 using Standard Platinum Resistance Thermometers (SPRT) calibrated at Defining Fixed Points (DFPs). The procedure allows correlations to be included between SPRT resistances measured during the calibration at the DFPs (i.e., the realization of the ITS-90) and the resistances measured during the

The article presents the modified structure of the two-level digital frequency synthesizer (TLDFS), which combines the properties of classical digital frequency synthesizers (DFS) and Poisson pulse sequence generators (PPSG). The analysis of the statistical characteristics of synthesizer output signal, obtained in computer modelling with the use of appropriate software, has been carried out, which

The aim of this paper is to determine inter-reliability, concurrent validity, and interchangeability of the SMS HG dynamometric system and a Jamar digital dynamometer for hand grip strength measurements performed in two relevant positions of the elbow joint, i.e. 90 ° flexion and 180 ° (full) extension. The sample in this research consisted of 61 participants and included 27 women and 34 men. Statistically

Lungs are used as an attractive possibility for administration of different therapeutic substances for a long time. An innovative method of such administration widely studied nowadays is the application of aerosolized magnetic particles as the carriers to the lungs in the external non-homogeneous magnetic field. For these reasons we have studied dynamics of such a system on a level of particle trajectory