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The creation of a virtual laboratory stand that allows one to obtain reliable characteristics that can be proven as actual, taking into account errors and noises (which is the main distinguishing feature of a computational experiment from model studies) is one of the main problems of this work. It considers the following task: there is a rectangular waveguide in the single operating mode, on the wide wall of which a technological hole is cut, through which a sample for research is placed into the cavity of the transmission line. The recovery algorithm is as follows: the laboratory measures the network parameters (S₁₁ and/or S₂₁) in the transmission line with the sample. In the computer model of the laboratory stand, the sample geometry is reconstructed and an iterative process of optimization (or sweeping) of the electrophysical parameters is started, the mask of this process is the experimental data, and the stop criterion is the interpretive estimate of proximity (or residual). It is important to note that the developed computer model, along with its apparent simplicity, is initially ill-conditioned. To set up a computational experiment, the Comsol modeling environment is used. The results of the computational experiment with a good degree of accuracy coincided with the results of laboratory studies. Thus, experimental verification was carried out for several significant components, both the computer model in particular and the algorithm for restoring the target parameters in general. It is important to note that the computer model developed and described in this work may be effectively used for a computational experiment to restore the full dielectric parameters of a complex geometry target. Weak bianisotropy effects can also be detected, including chirality, gyrotropy, and material nonreciprocity. The resulting model is, by definition, incomplete, but its completeness is the highest of the considered options, while at the same time, the resulting model is well conditioned. Particular attention in this work is paid to the modeling of a coaxial-waveguide transition, it is shown that the use of a discrete-element approach is preferable to the direct modeling of the geometry of a microwave device.

This work provides a new approach for constructing high-precision routes based on data from transport detectors inside the SUMO traffic modeling package. Existing tools such as flowrouter and routeSampler have a number of disadvantages, such as the lack of interaction with the network in the process of building routes. Our rlRouter uses multi-agent reinforcement learning (MARL), where the agents are incoming lanes and the environment is the road network. By performing actions to launch vehicles, agents receive a reward for matching data from transport detectors. Parameter Sharing DQN with the LSTM backbone of the Q-function was used as an algorithm for multi-agent reinforcement learning.

Since the rlRouter is trained inside the SUMO simulation, it can restore routes better by taking into account the interaction of vehicles within the network with each other and with the network infrastructure. We have modeled diverse traffic situations on three different junctions in order to compare the performance of SUMO’s routers with the rlRouter. We used Mean Absoluter Error (MAE) as the measure of the deviation from both cumulative detectors and routes data. The rlRouter achieved the highest compliance with the data from the detectors. We also found that by maximizing the reward for matching detectors, the resulting routes also get closer to the real ones. Despite the fact that the routes recovered using rlRouter are superior to the routes obtained using SUMO tools, they do not fully correspond to the real ones, due to the natural limitations of induction-loop detectors. To achieve more plausible routes, it is necessary to equip junctions with other types of transport counters, for example, camera detectors.

Instrument of numerical-analytical modeling of characteristics of propagation of electromagnetic waves in chaotic space plasma with taking into account effects of gravitation is developed for interpretation of data of measurements of astrophysical precision instruments of new education. The task of propagation of waves in curved (Riemann’s) space is solved in Euclid’s space by introducing of the effective index of refraction of vacuum. The gravitational potential can be calculated for various model of distribution of mass of astrophysical objects and at solution of Poisson’s equation. As a result the effective index of refraction of vacuum can be evaluated. Approximate model of the effective index of refraction is suggested with condition that various objects additively contribute in total gravitational field. Calculation of the characteristics of electromagnetic waves in the gravitational field of astrophysical objects is performed by the approximation of geometrical optics with condition that spatial scales of index of refraction a lot more wavelength. Light differential equations in Euler’s form are formed the basis of numerical-analytical instrument of modeling of trajectory characteristic of waves. Chaotic inhomogeneities of space plasma are introduced by model of spatial correlation function of index of refraction. Calculations of refraction scattering of waves are performed by the approximation of geometrical optics. Integral equations for statistic moments of lateral deviations of beams in picture plane of observer are obtained. Integrals for moments are reduced to system of ordinary differential equations the firsts order with using analytical transformations for cooperative numerical calculation of arrange and meansquare deviations of light. Results of numerical-analytical modeling of trajectory picture of propagation of electromagnetic waves in interstellar space with taking into account impact of gravitational fields of space objects and refractive scattering of waves on inhomogeneities of index of refraction of surrounding plasma are shown. Based on the results of modeling quantitative estimation of conditions of stochastic blurring of the effect of gravitational lensing of electromagnetic waves at various frequency ranges is performed. It’s shown that operating frequencies of meter range of wavelengths represent conditional low-frequency limit for observational of the effect of gravitational lensing in stochastic space plasma. The offered instrument of numerical-analytical modeling can be used for analyze of structure of electromagnetic radiation of quasar propagating through group of galactic.

Hemostasis system is one of the key body’s defense systems, which is presented in all the liquid tissues and especially important in blood. Hemostatic response is triggered as a result of the vessel injury. The interaction between specialized cells and humoral systems leads to the formation of the initial hemostatic clot, which stops bleeding. After that the slow process of clot dissolution occurs. The formation of hemostatic plug is a unique physiological process, because during several minutes the hemostatic system generates complex structures on a scale ranging from microns for microvessel injury or damaged endothelial cell-cell contacts, to centimeters for damaged systemic arteries. Hemostatic response depends on the numerous coordinated processes, which include platelet adhesion and aggregation, granule secretion, platelet shape change, modification of the chemical composition of the lipid bilayer, clot contraction, and formation of the fibrin mesh due to activation of blood coagulation cascade. Computer modeling is a powerful tool, which is used to study this complex system at different levels of organization. This includes study of intracellular signaling in platelets, modelling humoral systems of blood coagulation and fibrinolysis, and development of the multiscale models of thrombus growth. There are two key issues of the computer modeling in biology: absence of the adequate physico-mathematical description of the existing experimental data due to the complexity of the biological processes, and high computational complexity of the models, which doesn’t allow to use them to test physiologically relevant scenarios. Here we discuss some key unresolved problems in the field, as well as the current progress in experimental research of hemostasis and thrombosis. New findings lead to reevaluation of the existing concepts and development of the novel computer models. We focus on the arterial thrombosis, venous thrombosis, thrombosis in microcirculation and the problems of fibrinolysis and thrombolysis. We also briefly discuss basic types of the existing mathematical models, their computational complexity, and principal issues in simulation of thrombus growth in arteries.

The paper considers the application of swarm intelligence technology to build agent-based simulation models. As an example, a minimal model is constructed illustrating the influence of information influences on the rules of behavior of agents in the simplest model of competition between two populations, whose agents perform the simplest task of transferring a resource from a mobile source to their territory. The algorithm for the movement of agents in the model space is implemented on the basis of the classical particle swarm algorithm. Agents have a life cycle, that is, the processes of birth and death are taken into account. The model takes into account information processes that determine the target functions of the behavior of newly appeared agents. These processes (training and poaching) are determined by information influences from populations. Under certain conditions, a third population arises in the agent system. Agents of such a population informatively influence agents of other populations in a certain radius around themselves, changing.

As a result of the conducted simulation experiments, it was shown that the following final states are realized in the system: displacement of a new population by others, coexistence of a new population and other populations and the absence of such a population. It has been shown that with an increase in the radius of influence of agents, the population with changed rules of behavior displaces all others. It is also shown that in the case of a hard-to-access resource, the strategy of luring agents of a competing population is more profitable.

As it stands in the contemporary world, compliance with regulations concerning data protection such as GDPR is central to organizations. Another important issue analysis identified is the fact that compliance is hampered by the fact that legal documents are often complex and that regulations are ever changing. This paper aims to describe the ways in which NLP aids in keeping GDPR compliance effortless through automated scanning for compliance, evaluating privacy policies, and increasing the level of transparency. The work does not only limit to exploring the application of NLP for dealing with the privacy policies and facilitate better understanding of the third-party data sharing but also proceed to perform the preliminary studies to evaluate the difference of several NLP models. They implement and execute the models to distinguish the one that performs the best based on the efficiency and speed at which it automates the process of compliance verification and analyzing the privacy policy. Moreover, some of the topics discussed in the research deal with the possibility of using automatic tools and data analysis to GDPR, for instance, generation of the machine readable models that assist in evaluation of compliance. Among the evaluated models from our studies, SBERT performed best at the policy level with an accuracy of 0.57, precision of 0.78, recall of 0.83, and F1-score of 0.80. BERT showed the highest performance at the sentence level, achieving an accuracy of 0.63, precision of 0.70, recall of 0.50, and F1-score of 0.55. Therefore, this paper emphasizes the importance of NLP to help organizations overcome the difficulties of GDPR compliance, create a roadmap to a more client-oriented data protection regime. In this regard, by comparing preliminary studies done in the test and showing the performance of the better model, it helps enhance the measures taken in compliance and fosters the defense of individual rights in the cyberspace.

An effective regional policy in order to stabilize production is impossible without an analysis of the dynamics of economic processes taking place. This article focuses on developing a mathematical model reflecting the interaction of several economic agents with regard to their interests. Developing such a model and its study can be considered as an important step in solving theoretical and practical problems of managing growth.

This paper is devoted to investigation of the swirl flows. Such flows are widely used in various industrial processes. Swirl flows can be accompanied by time-dependent effects, for example, precession of the vortex core. In turn, the large-scale fluctuations due to the precession of the vortex can cause damage of structures and reduce of equipment reliability. Thus, for engineering calculations approaches that sufficiently well described such flows are required. This paper presents the technique of swirl flows calculation, tested for CFD packages Fluent and SigmaFlow. A numerical simulation of several swirl flow test problems was carried out. Obtained results are compared with each other and with the experimental data.

A simple non-linear model allowing to calculate daily and monthly GPP and NPP of forests using parameters characterizing the light-use efficiencies for GPP and NPP, and integral values of absorbed photosynthetically active radiation, obtained using field measurements and remotes sensing data was suggested. Daily and monthly GPP, NPP of the forest ecosystems were derived from the field measurements of the net ecosystem exchange of CO₂ in the spruce and tropical rain forests using a process-based Mixfor-SVAT model.

Study of work of heating equipment is an actual issue because it allows determining optimal regimes to reach highest efficiency. At that it is very helpful to use computer simulation to predict how different heating modes influence the effectiveness of the heating process and wear of heating equipment. Computer simulation provides results whose accuracy is proven by many studies and requires costs and time less than real experiments. In terms of present research, computer simulation of heating of air tuyere of blast furnace was realized with the help of FEM software. Background studies revealed possibility to simulate it as a flat, axisymmetric problem and DEFORM-2D software was used for simulation. Geometry, necessary for simulation, was designed with the help of SolidWorks, saved in .dxf format. Then it was exported to DEFORM-2D pre-processor and positioned. Preliminary and boundary conditions were set up. Several modes of operating regimes were under analysis. In order to demonstrate influence of eah of the modes and for better visualization point tracking option of the DEFORM-2D post-processor was applied. Influence of thermal insulation box plugged into blow channel, with and without air gap, and thermal coating on air tuyere’s temperature field was investigated. Simulation data demonstrated significant effect of thermal insulation box on air tuyere’s temperature field. Designed model allowed to simulate tuyere’s burnout as a result of interaction with liquid iron. Conducted researches have demonstrated DEFORM-2D effectiveness while using it for simulation of heat transfer and heating processes. DEFORM-2D is about to be used in further studies dedicated to more complex process connected with temperature field of blast furnace’s air tuyere.