Cybersecurity Risk Analysis of Industrial Automation Systems on the Basis of Cognitive Modeling Technology

The issues of procuring the cybersecurity of modern industrial systems and networks acquire special urgency because of imperfection of their protection tools and presence of vulnerabilities. International standards ISA/IEC 62443 offer the system risk-oriented approach to solve the tasks of providing the security of industrial control systems (ICS) at all stages of life cycle. But in view of high uncertainty and complexity of procedure of formalizing the factors affecting the final indices of system security, the problem of cybersecurity risk assessment remains open and requires applying new approaches based on the technology of data mining and cognitive modeling. Cognitive modeling of risk assessment using fuzzy grey cognitive maps (FGCM) allows us to take into account the uncertainty factor arising in the process of vulnerability probability assessment for each of security nodes. The interval estimates of FGCM connection weights can reflect the scatter of expert group opinions that allows us to take into account more completely the data available for risk analysis. The main stages of ICS security assessment with use of FGCM are analyzed in the chapter on the example of distributed industrial automation network. The recommendations concerning the choice of the necessary countermeasures improving the level of network security in the conditions of possible external and internal threats are considered

Boosting Heterogeneous Catalyst Discovery by Structurally Constrained Deep Learning Models

The discovery of new catalysts is one of the significant topics of computational chemistry as it has the potential to accelerate the adoption of renewable energy sources. Recently developed deep learning approaches such as graph neural networks (GNNs) open new opportunity to significantly extend scope for modelling novel high-performance catalysts. Nevertheless, the graph representation of particular crystal structure is not a straightforward task due to the ambiguous connectivity schemes and numerous embeddings of nodes and edges. Here we present embedding improvement for GNN that has been modified by Voronoi tesselation and is able to predict the energy of catalytic systems within Open Catalyst Project dataset. Enrichment of the graph was calculated via Voronoi tessellation and the corresponding contact solid angles and types (direct or indirect) were considered as features of edges and Voronoi volumes were used as node characteristics. The auxiliary approach was enriching node representation by intrinsic atomic properties (electronegativity, period and group position). Proposed modifications allowed us to improve the mean absolute error of the original model and the final error equals to 651 meV per atom on the Open Catalyst Project dataset and 6 meV per atom on the intermetallics dataset. Also, by consideration of additional dataset, we show that a sensible choice of data can decrease the error to values above physically-based 20 meV per atom threshold

The population history of northeastern Siberia since the Pleistocene.

Northeastern Siberia has been inhabited by humans for more than 40,000 years but its deep population history remains poorly understood. Here we investigate the late Pleistocene population history of northeastern Siberia through analyses of 34 newly recovered ancient genomes that date to between 31,000 and 600 years ago. We document complex population dynamics during this period, including at least three major migration events: an initial peopling by a previously unknown Palaeolithic population of 'Ancient North Siberians' who are distantly related to early West Eurasian hunter-gatherers; the arrival of East Asian-related peoples, which gave rise to 'Ancient Palaeo-Siberians' who are closely related to contemporary communities from far-northeastern Siberia (such as the Koryaks), as well as Native Americans; and a Holocene migration of other East Asian-related peoples, who we name 'Neo-Siberians', and from whom many contemporary Siberians are descended. Each of these population expansions largely replaced the earlier inhabitants, and ultimately generated the mosaic genetic make-up of contemporary peoples who inhabit a vast area across northern Eurasia and the Americas

Polarized blazar X-rays imply particle acceleration in shocks

Most of the light from blazars, active galactic nuclei with jets of magnetized plasma that point nearly along the line of sight, is produced by high-energy particles, up to around 1 TeV. Although the jets are known to be ultimately powered by a supermassive black hole, how the particles are accelerated to such high energies has been an unanswered question. The process must be related to the magnetic field, which can be probed by observations of the polarization of light from the jets. Measurements of the radio to optical polarization—the only range available until now—probe extended regions of the jet containing particles that left the acceleration site days to years earlier1,2,3, and hence do not directly explore the acceleration mechanism, as could X-ray measurements. Here we report the detection of X-ray polarization from the blazar Markarian 501 (Mrk 501). We measure an X-ray linear polarization degree ΠX of around 10%, which is a factor of around 2 higher than the value at optical wavelengths, with a polarization angle parallel to the radio jet. This points to a shock front as the source of particle acceleration and also implies that the plasma becomes increasingly turbulent with distance from the shock

Discovery of X-ray polarization angle rotation in active galaxy Mrk 421

The magnetic field conditions in astrophysical relativistic jets can be probed by multiwavelength polarimetry, which has been recently extended to X-rays. For example, one can track how the magnetic field changes in the flow of the radiating particles by observing rotations of the electric vector position angle $\Psi$. Here we report the discovery of a $\Psi_{\mathrm x}$ rotation in the X-ray band in the blazar Mrk 421 at an average flux state. Across the 5 days of Imaging X-ray Polarimetry Explorer (IXPE) observations of 4-6 and 7-9 June 2022, $\Psi_{\mathrm x}$ rotated in total by $\geq360^\circ$. Over the two respective date ranges, we find constant, within uncertainties, rotation rates ($80 \pm 9$ and $91 \pm 8 ^\circ/\rm day$) and polarization degrees ($\Pi_{\mathrm x}=10\%\pm1\%$). Simulations of a random walk of the polarization vector indicate that it is unlikely that such rotation(s) are produced by a stochastic process. The X-ray emitting site does not completely overlap the radio/infrared/optical emission sites, as no similar rotation of $\Psi$ was observed in quasi-simultaneous data at longer wavelengths. We propose that the observed rotation was caused by a helical magnetic structure in the jet, illuminated in the X-rays by a localized shock propagating along this helix. The optically emitting region likely lies in a sheath surrounding an inner spine where the X-ray radiation is released

X-ray Polarization Observations of BL Lacertae

Blazars are a class of jet-dominated active galactic nuclei with a typical double-humped spectral energy distribution. It is of common consensus the Synchrotron emission to be responsible for the low frequency peak, while the origin of the high frequency hump is still debated. The analysis of X-rays and their polarization can provide a valuable tool to understand the physical mechanisms responsible for the origin of high-energy emission of blazars. We report the first observations of BL Lacertae performed with the Imaging X-ray Polarimetry Explorer ({IXPE}), from which an upper limit to the polarization degree $\Pi_X<$12.6\% was found in the 2-8 keV band. We contemporaneously measured the polarization in radio, infrared, and optical wavelengths. Our multiwavelength polarization analysis disfavors a significant contribution of proton synchrotron radiation to the X-ray emission at these epochs. Instead, it supports a leptonic origin for the X-ray emission in BL Lac.Comment: 17 pages, 5 figures, accepted for publication in ApJ

New Type of Detachable Contact Joints for Aluminium Cell Busbar Arrangement

The new type of detachable contact joints (DJC) for the aluminium industry is offered. It is shown, that DJC with cylindrical split contact inserts allow to provide stability of electrotechnical characteristics of connection from -50 to + 40ºC

New Type of Detachable Contact Joints for Aluminium Cell Busbar Arrangement

The new type of detachable contact joints (DJC) for the aluminium industry is offered. It is shown, that DJC with cylindrical split contact inserts allow to provide stability of electrotechnical characteristics of connection from -50 to + 40ºC

Shok-free Dismounting of Cathode Assembly Lining of Aluminum Cells

Рассматривается технология демонтажа футеровки катодного устройства при капитальном ремонте алюминиевых электролизеров непосредственно в корпусах электролиза. Для ускорения процесса разрушения футеровки и снижения воздействия ударно-вибрационных нагрузок при выполнении демонтажных работ на соседние с ремонтируемым катодным устройством электролизеры, демонтаж выполняется с использованием гидропрессового оборудования для безударного разрушения материалов с применением инструментов алмазной резки и бурения. Ускорение процесса демонтажа достигается за счет использования гидропрессового оборудования, позволяющего создать в материале футеровки катодного устройства электролизера локально неоднородное распределение давления, обеспечивающего образование трещин, разрушающих целостность футеровки.The technology of dismantle of the cathodic device of electrolytic furnaces is considered. Lining destruction in the cathodic device of an electrolytic furnace is made by a special hydraulic press. In a lining material locally non-uniform loadings causing occurrence of cracks are created. The technology allows to exclude with great dispatch-vibrating influence on near electrolytic furnaces and to increase term of their operation