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In the paper, polycrystalline copper deformed by tension under different conditions of loading has been studied using electron backscatter diffraction. The microstructure of areas located on the longitudinal section of the specimens deformed until fracture was examined. The fragmentation of initial grains in case of deformation at room temperature was observed whereas at 400°С, considerable dynamic recovery and recrystallization significantly influenced the microstructure formation. A procedure for computer analysis of the orientation maps has been put forward, which allows separating recrystallized regions from the non-recrystallized ones and further analyzing the misorientation statistics of strain-induced boundaries. A scaling behavior of the strain-induced misorientation distributions was shown to take place. The mechanism of strain-induced boundary evolution was proved to remain unchanged for all studied deformation conditions, in spite of recovery and recrystallization occurring at elevated temperatures.

The recently observed helicity-sensitive response, occurring in graphene based field-effect transistors (FETs) is interpreted as a result of the intrinsic phase asymmetry of these devices and interference of plasmons in the FET channel. The graphene-based plasmonic interferometers presented in this work enable the room temperature detection of THz radiation as well as allows us to distinguish between the rotation direction of circular polarized waves. To illustrate the broadband nurture of the observed effects, similar measurements were carried out at both THz and mid-infrared frequencies. The precise control of the carriers type and their concentration throughout the channel length allows us to demonstrate the helicity-sensitive response over a wide range of the gate potentials (from negative to positive values). We experimentally show that the formation of p–n junction inside the graphene channel leads to additional scattering of excited plasma waves, resulting in the suppression of their interference and consequent reduction of the helicity-sensitive contribution.

The work highlights the results of a study into the dual wedge-shaped wear of composite brake pads for freight wagons. It has been found that the over-normative wear makes the area of a composite brake pad larger in the lower part up to a value directly proportional to the wagon mileage and smaller in the upper part. To assess the braking efficiency of a rail vehicle, a graphical analytical method has been developed; it allows determining the factor of dual wedge-shaped wear of pads depending on the wagon mileage. The results of calculation were verified by comparing two samplings obtained by mathematical and computer modelling. The results of calculation have proven that the hypothesis on the adequacy is not rejected. The results of the study conducted will allow more accurate assessment of the braking efficiency of freight rolling stock to be made, as well as contribute to improving the safety of train traffic.

Discrete chaotic maps are a mathematical basis for many useful applications. One of the most common is chaos-based pseudorandom number generators (PRNGs), which should be computationally cheap and controllable and possess necessary statistical properties, such as mixing and diffusion. However, chaotic PRNGs have several known shortcomings, e.g., being prone to chaos degeneration, falling in short periods, and having a relatively narrow parameter range. Therefore, it is reasonable to design novel simple chaotic maps to overcome these drawbacks. In this study, we propose a novel fractal chaotic tent map, which is a generalization of the well-known tent map with a fractal function introduced into the right-hand side. We construct and investigate a PRNG based on the proposed map, showing its high level of randomness by applying the NIST statistical test suite. The application of the proposed PRNG to the task of generating surrogate data and a surrogate testing procedure is shown. The experimental results demonstrate that our approach possesses superior accuracy in surrogate testing across three distinct signal types—linear, chaotic, and biological signals—compared to the MATLAB built-in randn() function and PRNGs based on the logistic map and the conventional tent map. Along with surrogate testing, the proposed fractal tent map can be efficiently used in chaos-based communications and data encryption tasks.

In this article, we consider designs of simple analog artificial neural networks based on adiabatic Josephson cells with a sigmoid activation function. A new approach based on the gradient descent method is developed to adjust the circuit parameters, allowing efficient signal transmission between the network layers. The proposed solution is demonstrated on the example of a system that implements XOR and OR logical operations.

Josephson junctions (JJs) are superconductor-based devices used to build highly sensitive magnetic flux sensors called superconducting quantum interference devices (SQUIDs). These sensors may vary in design, being the radio frequency (RF) SQUID, direct current (DC) SQUID, and hybrid, such as D-SQUID. In addition, recently many of JJ’s applications were found in spiking models of neurons exhibiting nearly biological behavior. In this study, we propose and investigate a new circuit model of a sensory neuron based on DC SQUID as part of the circuit. The dependence of the dynamics of the designed model on the external magnetic flux is demonstrated. The design of the circuit and derivation of the corresponding differential equations that describe the dynamics of the system are given. Numerical simulation is used for experimental evaluation. The experimental results confirm the applicability and good performance of the proposed magnetic-flux-sensitive neuron concept: the considered device can encode the magnetic flux in the form of neuronal dynamics with the linear section. Furthermore, some complex behavior was discovered in the model, namely the intermittent chaotic spiking and plateau bursting. The proposed design can be efficiently applied to developing the interfaces between circuitry and spiking neural networks. However, it should be noted that the proposed neuron design shares the main limitation of all the superconductor-based technologies, i.e., the need for a cryogenic and shielding system.

Abstract Figurative depictions in art first occur ca. 50,000 years ago in Europe, Africa, and Southeast Asia. Considered by most as an advanced form of symbolic behavior, they are restricted to our species. Here, we report a piece of ornament interpreted as a phallus-like representation. It was found in a 42,000 ca.-year-old Upper Paleolithic archaeological layer at the open-air archaeological site of Tolbor-21, in Mongolia. Mineralogical, microscopic, and rugosimetric analyses points toward the allochthonous origin of the pendant and a complex functional history. Three-dimensional phallic pendants are unknown in the Paleolithic record, and this discovery predates the earliest known sexed anthropomorphic representation. It attests that hunter-gatherer communities used sex anatomical attributes as symbols at a very early stage of their dispersal in the region. The pendant was produced during a period that overlaps with age estimates for early introgression events between Homo sapiens and Denisovans, and in a region where such encounters are plausible.

The progress in technologies of Internet of Things (IoT) and Artificial Intelligence (AI) lead to the digitalization in various domains of human activity. In this demo, we show a digital inspector that recognizes the physical human activity with sports training equipment (mechanical simulators). We experiment with outdoor simulators produced by the MB Barbell company and located on the shore of Lake Onega in the Petrozavodsk city for free use by citizens and guests. We implemented multi-camera video surveillance system (VSS) that statistically evaluates the states of the sports equipment use such as “the simulator is occupied by a person”, “the simulator is not correctly used”, “the simulator is occupied but not in use”, etc. The evaluation is based on well-known AI methods for image recognition, which are customized for real-time inspection. The evaluated statistics for the area with sports equipment is important for the municipality to understand the efficiency of the provided public resources for well-being and comfort life.

In the Russian Empire, subjects wrote letters to each other daily, in which they poured out their souls, shared their emotions and feelings, were indignant, worried. Separate letters represented samples of Russian literature. One of the most prolific writers was Anatoly Fedorovich Koni. He wrote daily up to 1015 letters. Much of this correspondence has been preserved. Thanks to the letters, we can reveal the psychological makeup of the famous lawyer, establish numerous personal connections in which he was involved and in which he played an important role. Koni was a politician, one of the leaders of the legalist (legal) movement in the late empire. We felt that identifying and analyzing these letters would allow us to better understand the motivations of the leaders of this movement. Accordingly, the subject of our study is the political worldview of the liberal lawyers of the Russian Empire based on the materials of Konis letters and letters to him. Considering the history of correspondence, we chose the chronological approach as the main method, trying to trace the evolution of the legalists views from moderate optimism to deep pessimism. This is the first time such a reconstruction has been carried out in relation to the legalist movement and contributes to our historical knowledge. A number of preliminary conclusions can be formulated. The letters are an important source on the history of the political sentiments of the empires liberal jurists. They not only reflected emotional reactions to the ongoing processes, but also proposed ideas for restructuring the state. Along with the criticism of the state, we fix the naive faith of the followers of B.N. Chicherin into the democratization of an authoritarian state, liberalization, into the Constitution, as a way to solve the main problems, into a God-bearing people, in which some creative forces are dormant. All these dreams are dispelled by the end of the XIX century, and only a deep spiritual decline remains, which means a crisis and collapse of the movement.

In the present study, we propose a new transparent thin-film ITO surface radio-frequency (RF) trap. Charged hybrid microstructures were localized in the developed ITO trap. We show, analytically and experimentally, that the position of the localization zones in the trapped hybrid structure are stable. The transfer of charged particles between localization zones was studied under the action of gravity-compensating laser radiation. We highlight the advantages of transparent thin-film ITO traps to investigate and manipulate charged particles.

The purpose of the study. To assess the relationship between Internet addictive behavior and clip thinking in schoolchildren Materials and methods. 59 students of both sexes of the 8th grade of secondary school № 84 of Krasnoyarsk took part in the study. A modified test based on the J.S. Bruner questionnaire was used to diagnose the clip type of thinking. The level of Internet addiction was assessed using the CIAS scale. Results. A pronounced and stable pattern of Internet addictive behavior on the CIAS scale was detected in 15,2% of the surveyed schoolchildren, among whom there were three times more girls compared to boys. The frequency of gambling addiction was higher in boys than in girls, while the frequency of dependence on social networks was 2 times higher among girls. The clip type of thinking was revealed in a third of the surveyed schoolchildren with the same frequency among both boys and girls. At the same time, persons with a theoretical type of thinking were more common among girls, and with a creative type of thinking – among boys. In Internet-addicted girls and boys, clip-type thinking was detected in half of the subjects in both groups. Conclusion. Among the identified students with the clip type of thinking, 50% belonged to people with Internet addictive behavior.

Many multi-camera systems organize video surveillance - a process designed to visually control a certain area and / or objects. The most modern systems organize smart video surveillance - the process of collecting and subsequent analysis of incoming information using modern technologies and designed to ensure security in those places where it is necessary. At the moment, there are a large number of algorithms and methods used in video analytics systems - a technology that uses computer vision methods for automated data acquisition based on the analysis of images from video cameras in real time. Such video analytics systems are mainly used in special services. In the case of commercial and public use, they are expensive or not available. The claimed system can be quite flexibly upgraded to suit the customer’s tasks, while having a low cost. At the moment, security systems in the field of video analytics are not widely used in the Republic of Karelia (RK). Video analytics is either completely absent or presented in the form of the most primitive recognition algorithms. Ensuring the digital security of the Republic of Karelia in public places and crowded places and the development of digital security support technologies in the region are among the highest priority areas of this work.

Robotic manipulators are widely employed in industry for automating repetitive tasks. A particular use case is sorting of waste materials. Movement of such a manipulator is subject for control since defects can occur during the operation. The assessment of operation quality can be also delegated from human to machine based on the progress in Artificial Intelligence (AI). In this demo, we consider video-based assessment as a promising approach for industrial robotics. We demonstrate our computer vision-based procedure for assessing the operation quality of a robotic manipulator. The experimental setup uses a single camera to detect successful and unsuccessful manipulations with objects, including the object loss during transmission in real time.

We present a simple and affordable method for making a surface electrodynamic trap for microparticles. The principles of electrodynamic trapping of charged particles are discussed and step-by-step instructions on how to make a surface trap are given. In addition to the electrodynamic trap implementation and operation process, options for its further use are proposed. The work may be of interest to physics teachers as a material for practical work, for the formation of students' skills in performing a physical experiment.

Computer simulation of continuous chaotic systems is usually performed using numerical methods. The discretization may introduce new properties into finite-difference models compared to their continuous prototypes and can therefore lead to new types of dynamical behavior exhibited by discrete chaotic systems. It is known that one can control the dynamics of a discrete system using a special class of integration methods. One of the applications of such a phenomenon is chaos-based communication systems, which have recently attracted attention due to their high covertness and broadband transmission capability. Proper modulation of chaotic carrier signals is one of the key problems in chaos-based communication system design. It is challenging to modulate and demodulate a chaotic signal in the same way as a conventional signal due to its noise-like shape and broadband characteristics. Therefore, the development of new modulation–demodulation techniques is of great interest in the field. One possible approach here is to use adaptive numerical integration, which allows control of the properties of the finite-difference chaotic model. In this study, we describe a novel modulation technique for chaos-based communication systems based on generalized explicit second-order Runge–Kutta methods. We use a specially designed test bench to evaluate the efficiency of the proposed modulation method and compare it with state-of-the-art solutions. Experimental results show that the proposed modulation technique outperforms the conventional parametric modulation method in both coverage and noise immunity. The obtained results can be efficiently applied to the design of advanced chaos-based communication systems as well as being used to improve existing architectures.