Determination of the Coordinates of the Center of a Gaussian Beam by Means of a Matrix Photodetector Using a Weighting Method

A weighting algorithm to determine the coordinates of the center of a Gaussian laser beam projected onto a matrix photodetector is considered. The influence of the internal noise of the photodetector, the maximum brightness of the signal at the beam maximum, and the beam radius on the precision of the algorithm is investigated. Recommendations on image processing are presented.     

The adaptive approach to abnormal situations recognition using images from condition monitoring systems

Decision support in equipment condition monitoring systems with image processing is analyzed. Long-run accumulation of information about earlier made decisions is used to realize the adaptiveness of the proposed approach. It is shown that unlike conventional classification problems, the recognition of abnormalities uses training samples supplemented with reward estimates of earlier decisions and can be tackled using reinforcement learning algorithms. We consider the basic stages of contextual multi-armed bandit algorithms during which the probabilistic distributions of each state are evaluated to evaluate the current knowledge of the states, and the decision space is explored to increase the decision-making efficiency. We propose a new decision-making method, which uses the probabilistic neural network to classify abnormal situation and the softmax rule to explore the decision space. A modelling experiment in image processing was carried out to show that our approach allows a higher accuracy of abnormality detection than other known methods, especially for small-size initial training samples.     

Analytical review of methods of providing internet anonymity

The Internet community all over the world is showing growing interest in a subject of information security and anonymity on the Internet, especially after revelations of Edward Snowden, when it became known about mass spying by certain organizations (such as the US National Security Agency) on Internet users, companies, political organizations, etc. This led to the active development of various anonymous networks, VPN services, proxies, etc. The aim of this article is to review popular methods of providing Internet anonymity, compare them, and discover their benefits and disadvantages.     

Transport properties of LaSrNi1 − x ScxOy solid solutions

The formation of LaSrNiO₄-and LaSrScO₄-based solid solutions with the general stoichiometry LaSrNi_{1 ? x} Sc_xO₄ (0 < x < 1) has been studied in air at temperatures from 700 to 1300°C. According to x-ray diffraction results, the former solid solutions exist in the composition range 0 < x ≤ 0.2. Their lattice parameters have been determined, and their resistivity and thermoelectric power have been measured as functions of temperature. Oxygen release and absorption measurements at temperatures from 20 to 1000°C and oxygen partial pressures from 2 to 330 Pa suggest that the presence of scandium has a stabilizing effect on the oxygen sublattice of the solid solutions. The possible mechanisms of this effect are discussed.     

Studying magnetic stray field at the surface of elastostrained extensive object

Application of metal magnetic memory effect to revealing stress-concentration zones (SCZ) that occur in a specimen due to cyclic loads within the elastic deformation domain is considered. Experimental data are provided on the search for a correlational dependence between the magnetic stray field of a hot-rolled no. 6 channel bar and the stresses in the domains of elastic and plastic deformation.     

Estimation of the Phonetic Speech Quality Using the Information Theoretic Approach

The problem of estimation of the speech phonetic quality using a short fragment of the voice signal is formulated. The Kullback–Leibler minimum information discrimination principle is used to propose a novel criterion and develop an algorithm. The dynamic properties of the algorithm are analyzed. The algorithm is employed in the analysis of the functional state of speaker using the voice signal. It is demonstrated that the needed duration of the voice signal is several minutes only.     

Purification of undergound waters of manganese compounds using a natural sorbent-catalyst

Natural underground waters often contain manganese ions in such amount that the water becomes hazardous for human health. We have developed the technology of obtaining sorbent-catalyst based on oxide-carbonate ore of the Nikopol Deposit (Ukraine). We have also determined conditions for using the given material for purification of underground water with a high content of manganese.