Vol 73, No 3 (2023)

A methodology is being developed for estimating the dynamic states of technical objects of transport or technological purpose under conditions of vibration loads. Mechanical oscillatory systems with concentrated parameters are used as calculation schemes. A structural approach is applied, within the framework of which structural schemes of dynamically equivalent automatic control systems are aligned with mechanical oscillatory systems. Within the framework of the developed concepts, it is shown that the sets of dynamic states of parametric families of mechanical oscillatory systems can be characterized by finite sets of dynamic invariants.

The article is devoted to further development of the topic of applying the extended Girsanov principle for heavy-tailed distributions. The extended Girsanov principle involves finding the conditional mathematical expectation of the ratio of prices of underlying assets of option contracts at the current time to prices of underlying assets at the previous time. To do this, it is necessary to choose an appropriate model that will best describe the dynamics of this price ratio. The linear return or logarithmic return is typically used as the modeling object. In the case of linear returns, the risk-neutral dynamics for the heavy-tailed distribution (Su Johnson) was obtained in [1]. In [2], the effectiveness of the found martingale measure was demonstrated in the example of option contract valuation. However, there may be a need to use logarithmic returns, which have several useful properties (non-negativity of underlying asset prices, symmetry with respect to price increases and decreases). This article derives the martingale measure for the case where the approximation of logarithmic returns is considered. In the simplest case, the approximation coincides with linear returns, and as the degree of approximation increases, it approaches logarithmic returns.

This paper proposes a modified version of the Viola-Jones algorithm to improve the accuracy of object localization in document images when searching for and locating a stamp. The modification involves expanding the feature space with square centrally symmetric features, resulting in a significant increase in accuracy. The effectiveness of this approach is demonstrated through its application to locating the official stamp on Russian Federation passports, and the paper provides quantitative estimates of the improvement achieved.

This article presents a formal description of the conceptual model of the 1st kind at the object and specific levels for the subject task, which represents documented technical knowledge, taking into account the varying degree of their formalization and stratification of the conceptual model into constant information.

Criteria have been selected in the form of ranges boundaries for ranking information storage devices by reliability based on their distribution by SMART parameters values presented in the public domain by Backblaze data centers over a long period. As a result, the following criteria were determined: 0 – for a point range of drives with zero values of reliability indicators; 1 – for another point range of drives with at least one reliability indicator having a value equal to one; 2-8 – for drives whose value of at least one reliability indicator is greater than one, but does not exceed eight, i.e. one track of write/read sectors; >8 – a semi-open range of drives with values of at least one reliability indicator exceeding eight units.

The purpose of the article is modeling the efficiency system assessment of network infrastructure subsystems development and identifying their natural monopoly properties. Methods and models of natural monopoly theory, nonlinear network transport projection and variation analysis are used. The spectrum of models for identifying the natural monopoly properties of the network transport infrastructure, corresponding to changes in the parameters of the total cost functions, has been researched. Applying to modeling the development of fragments of regional transport network, computational algorithms for efficiency system assessment have been elaborated. The influence of the effect of natural monopoly synergy as the sphere of positive values of the economy of scope based on subadditivity testing for cost function has been specified. The results of calculations are presented related both specifying the assessment methodology under diagnostics of natural monopoly properties (primarily using special extensions of algorithms for finding the optimal transportation technology), and with modifications of computational experiments and quantitative assessment with variations of the factors.

A mathematical model of the dynamics of the “parasite-host” system was studied, in which the duration of immunity maintenance is not fixed, but distributed and depends on the characteristics of a particular host organism. It is found that for a contact number greater than one, there exists a unique non-trivial stationary solution that is a global attractor. With regard to the COVID-19 pandemic, this means that if no new variants of the pathogen arise, then under constant conditions, the incidence will stabilize. The impact on the decay rate of small deviations in incidence for the “parasite-host” system with the presence of groups differing in the duration of immunity was studied. It was found that for values R0 corresponding to COVID-19, the solution has the form of a twisting spiral with a period of about a year.

The COVID-19 pandemic has moved into the stage of a dynamic confrontation between the pathogen mutating in the regions and accumulating (natural and vaccine) population immunity. Pandemic influenza strains in a similar collision faded after three waves. SARS-COV-2 has an amazing rate of renewal of several of its structural proteins at once, which leads to new oscillations in the number of infections and competition between the evolutionary branches of virus strains. The variety of strains and variability of virus antigens periodically increases, but then some strains go out of distribution, but the rest give rise to new branches. Dynamically, this is reflected in waves of the number of recorded infections, the frequency and amplitude of peaks of which vary significantly in the regions. This is how regional epidemic scenarios are formed, some of which are quite unusual. Classical damped oscillations have been observed in South Africa. In spring of 2023, the next 7th local COVID wave begins in Australia. For a phenomenological model description of the observed dynamics, we propose to use equations with delay is flexible tool for describing complex forms of oscillatory dynamics, where we proposed to include special threshold damping functions. It was possible to obtain solutions for both collapsing and damped oscillations with the possibility of new outbreak, which made it possible to describe the effect of single extreme wave that arose in early 2022 in New York and earlier in Brazil after an increase in the length of active infection chains, a sharp Λ-shaped peak with vibrational damping. The scenario differs significantly from both the primary outbreak and Japanese epidemic scenario – a series of successive short-term waves with increasing amplitude. Only slowing down the evolution of the virus can stop the pandemic, and heterogeneity of population immunity become an important factor, if antibodies are developed for the same epitopes, then changes in these protein regions trigger another wave. In august, earlier than the forecast, COVID-wave of the strain EG.5 "Eris" began.

The results of the study of the problem of ensuring the safe development of Russia in the XXI century in the context of the creation of a national ideology are presented. It is shown that in the conditions of Russia’s civilizational confrontation with the countries of the Western world and the unprecedented increase in geopolitical tensions, Russia’s security cannot be ensured at the proper level without creating a nationwide ideology capable of consolidating Russian society. We are talking about the very survival of Russia, the protection of our cultural and civilizational code.