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Abstract Research into new composites utilizing cubic boron nitride (PcBN) shows promise for enhancing cutting tool performance. The unique properties of these materials stem from the addition of microfibers made of refractory compounds to their structure. This study looks at developing two-layer composites based on cBN group BL, reinforced with SiCw and Al2O3w microfibers. The goal is to improve tool stability when cutting hardened steels with impact loads. PcBN composite samples were made by sintering a mixture of cBN powder with bundles and microfibers under 7.7 GPa pressure. Bond material selection was based on analyzing the relationship between Poisson's ratio (η) and plasticity parameter (G/B). The density, Young's modulus, Poisson's ratio, and hardness of the composites were determined, and the microstructure of samples with TiCN bond was studied. Tool-life tests were conducted on two-layer cutting inserts made of PcBN reinforced with SiCw and Al2O3w microfibers during the machining of hardened KhVG steel (HRC 55) under impact loads at cutting speeds of 100 and 200 m/min.

Purpose: of the article is to develop a model of the value system of Russian youth, which can form the basis for the formation of the orientations of young people necessary for the state, contributing to the sustainable development of the Russian Federation. Methods: the article used both traditional methods of scientifi c analysis and methods of Bayesian intelligent measurement methodology used in conditions of uncertainty, inaccuracy and incompleteness of data characteristic of social and socio-economic systems. Results: in the presented study, the extensible hierarchical information model of the value system of Russian youth has been developed. The methodology for processing questionnaire data has been developed, the results of which are presented on numerical and linguistic scales, which makes it possible to take into account the uncertainty of the information received. According to the results of the survey of university students of 10 subjects of the Russian Federation aged 17 to 30 years, a total of 1816 people obtained the values of factors characterizing the value world of Russian youth, which allowed her to form her portrait. Some value factors of young people of the Tula region are evaluated and analyzed. Conclusions and Relevance: the proposed model and methodology for processing personal data allows us to create the adequate holistic portrait of Russian youth in modern economic conditions. The formation of two groups of young people characterized by unfavorable and favorable value attitudes towards Russian society has been revealed, which in the future may lead to a confl ict of social and economic interests, thereby negatively aff ecting the pace of economic growth and sustainable development of the state. In order to reduce internal tension between youth groups and the formation of values inherent in Russian society, measures at the federal and regional levels are proposed.

The paper discusses the results of the experimental investigation of the performance of several grades of PcBN cutting composites in conditions of the interrupted machining of hardened steel. Both BH and BL types of PcBN indexable inserts with additions of Si3N4, TiC, and TiCN were tested, and cutting speed varied to assess the possibility of applying these cutting tools in different conditions. It has been shown that BL PcBN can be utilized for turning with shock loads in case of high cutting speed and low depth of cut (0,2 mm). While in the range of comparatively low cutting speeds BL cutting tools are actually inoperable, and because of microchipping of polycrystalline fragments and brittle destruction of the cutting edge, an increase of the cutting speed to 210 m/min changes wear pattern and formation of the wear land. As well as this, measurement of the form and values of the cutting forces impulses revealed the effect of their peak growth by up to 40%. The danger of shock impulses was analyzed by FEM modeling, and it was demonstrated that during impacts, the maximal value of the third Principal stress exceeds the average level of compressive stresses during continuous cutting by 1.6 times, which can cause damage to the cutting tool. The data on the estimation of tool fracture probability depending on loading conditions are presented, and the possibility of reducing such probability is shown.

Analog-to-feature (A2F) conversion based on non-uniform wavelet sampling (NUWS) has demonstrated the ability to reduce energy consumption in wireless sensors while employed for electrocardiogram (ECG) anomaly detection. The technique involves extracting only relevant features for a given task directly from analog signals and conducting classification in the digital domain. Building on this approach, we extended the application of the proposed generic A2F converter to address a human activity recognition (HAR) task. The performed simulations include the training and evaluation of neural network (NN) classifiers built for each application. The corresponding results enabled the definition of valuable features and the hardware specifications for the ongoing complete circuit design. One of the principal elements constituting the developed converter, the integrator brought from the state-of-the-art design, was modified and simulated at the circuit level to meet our requirements. The revised value of its power consumption served to estimate the energy spent by the communication chain with the A2F converter. It consumes at least 20 and 5 times less than the chain employing the Nyquist approach in arrhythmia detection and HAR tasks, respectively. This fact highlights the potential of A2F conversion with NUWS in achieving flexible and energy-efficient sensor systems for diverse applications.

Introduction. The article discusses the harmful factors of foundry production. The authors analyze and evaluate the workplace of the operator of the shot blasting chamber and offer technical solutions to improve working conditions and reduce the development of occupational diseases.Problem Statement. The objective of this study is to assess the impact of noise and dust pollution on the production sites of the foundry.Theoretical Part. In the course of the study, the most polluted areas were identified with the exceeding permissible values of the considered indicators of noise level and dust content. These are the areas of shake-out grids and casting cleaning. Measures to improve the situation were proposed, such as: organization of acoustics taking into account the characteristics of the production room (acoustic screens, soundproof partitions), a suitable sound absorption area of the premises, the improvement of sound absorption by upgrading the body of the shot blasting chamber.Conclusions. The results of the analysis indicate a sufficiently high level of influence of harmful production factors on the operators of the shot blasting section of the foundry and the need to strengthen labor protection in this area.

Introduction. In order to determine the height of the rise of the polluted substances above the source of the pollution, it is important to know the exact distribution of the gas plume.Problem Statement. The determination of the dust concentration in the working area of asphalt concrete plants should take into account the assessment of the concentration of harmful substances in the working area of the asphalt concrete plant. The study is the analysis of methods for determining the effective height of the pipe, taking into account the dispersion of emissions in the working area.Theoretical Part. The paper considers the dependences of the estimation of the initial rise of the gas jet, proposed by Berland, Holland, Briggs, and the specialists of the Tennessee Valley. The value of the initial rise of the impurity jet depends on the moment of the amount of gas movement, the thermal power of the wind speed carrying the jet, and the conditions of thermophoresis. The paper presents the comparative graphs of the calculation of the level of the initial rise of the gas jet at different rates of gas exit from the pipe and constant wind speed.Conclusion. The method of taking into account the initial rise of the heated gas jet gives us better convergence in the calculations of the maximum surface concentrations of harmful substances and in the estimation of distances to them.

This article presents a clinical case of treatment of a patient with concomitant trauma. The increase in intra-abdominal pressure (IAP), as a predictor of the development of pancreatitis, was controlled by the developed method of radiation diagnostics. A method for assessing an increase in IAP, as a predictor of acute pancreatitis, is to quantify the volumetric blood flow in the superior mesenteric artery (SMA) and superior mesenteric vein (SMV) by Doppler ultrasound.

In this paper, we explore the optimization of virtual power plants (VPP), consisting of a portfolio of biogas power plants and a battery whose goal is to balance a wind park while maximizing their revenues. We operate under price and wind production uncertainty and in order to handle it, methods of machine learning are employed. For price modeling, we take into account the latest trends in the field and the most up-to-date events affecting the day-ahead and intra-day prices. The performance of our price models is demonstrated by both statistical methods and improvements in the profits of the virtual power plant. Optimization methods will take price and imbalance forecasts as input and conduct parallelization, decomposition, and splitting methods in order to handle sufficiently large numbers of assets in a VPP. The main focus is on the speed of computing optimal solutions of large-scale mixed-integer linear programming problems, and the best speed-up is in two orders of magnitude enabled by our method which we called Gradual Increase.

Nanostructured coatings based on amorphous carbon and carbon-doped with gold, silver, and nitrogen were obtained by the pulsed vacuum-arc method. Carbon coatings have been annealed in a vacuum as well as treated with argon ions. The alloying of carbon coatings with elements that do not form chemical bonds with the carbon matrix (Ag, Au) leads to the formation of gold or silver nanocrystallites with sizes of 2 ‑ 20 nm in the matrix of amorphous carbon, whose density depends on the concentration of the doping element. Annealing of silver-doped carbon coatings leads to the formation of islands on the surface with the size of the order of micrometers. This is due to the silver diffusion and coalescence of small islands into larger ones. The HRTEM method discovered the effect of twinning in carbon nanocrystallites after vacuum annealing as well as silver and gold in the initial state (the formation of single-crystal regions with an altered orientation of the crystal structure) in the amorphous carbon matrix. Analysis of Raman spectra of pure carbon coating and silver-doped showed that the addition of silver leads to a decrease in sp3-phase in the carbon matrix. This effect is particularly evident in the nature of changes in the spectra after vacuum annealing at 600 ºC. The addition of nitrogen in the carbon coating leads to an increase in the sp2 ‑ phase fraction, and additional annealing leads to a significant increase in the D - peak intensity and formation of clusters of the order of 5 ‑ 15 nm, which are not localized but fill the entire space. Analysis of the coating a-C: Au irradiation with argon ions shows that the number of nanopitches decreased after ion irradiation, simultaneously decreased surface roughness degree, besides, decreased electrical conductivity of the coating as a result of decreased gold content. It was found that the conditions of nanostructured coatings and their subsequent processing allow controlling the properties of nanocoatings (structure, size of nanoparticles, surface topography, and electrical conductivity).

Objective: to assess quality-of-life (QoL) dynamics in patients with rheumatoid arthritis (RA) when initiating therapy with biological agents (BAs) in real clinical practice.Patients and methods. The investigation enrolled patients with RA from the patient cohort participating in the TERMINAL-II multicenter Russian study, who newly initiated BA therapy. In the self-assessment terminal, the patient completed HAQ, EQ-5D, and RAPID-3 questionnaires. DAS28, SDAI, CDAI, and RAPID-3 were used to determine disease activity. The patient's functional status and QoL were assessed using the HAQ index and the EQ-5D questionnaire, respectively. The efficiency of the therapy was analyzed 6 months after the start of the study according to the standard procedures.Results and discussion. The investigation enrolled 156 RA patients: 79.6% females; mean age, 45.8±13.2 years; disease duration, 7.6±5.6 years. The patients had high RA activity (a mean DAS28 of 5.2±1.2, a mean SDAI of 39.5±16.4, a mean CDAI of 27.5±10.4, and a mean RAPID-3 of 15.1±3.6) and previous inefficacy of synthetic disease-modifying antirheumatic drugs (DMARDs) after at least 6 months of therapy. Only 1.2% of patients had a good functional status comparable to the population-based control (HAQ 40.5). 70% of patients needed to take non-steroidal anti-inflammatory drugs (NSAIDs). The first BA was chosen in accordance with the recommendations for administration of BAs and in terms of their availability in a specific region of the Russian Federation. The first prescribed BA was tumor necrosis factor-a (TNF-a) inhibitors in 112 (71.8%)patients, anti-B-cell therapy in 14 (9.0%), an interleukin-6 receptor inhibitor in 16 (10.3%), and a leukocyte costimulatory inhibitor in 14 (9.0%). Comparison of the patients receiving newly initiated therapy with TNF-a inhibitors and drugs with other mechanisms of action showed that the patients who had abatacept received higher doses of methotrexate (MTX), but lower doses of glucocorticoids (GCs) than those who were prescribed rituximab and tocilizumab. A statistically significant decrease in DAS28, SDAI, CDAI, and RAPID-3 scores was achieved after 6 months of therapy. Improvements of functional status and QoL in patients were also noted (p

This paper provides a comparative analysis of results of estimating specific efficacy that characterizes the amount of gross regional product depending on expenditure on technological innovations, the fixed capital and the average annual number of persons employed. This approach includes comparison of actual data with normative values calculated for three types of models: linear, logarithmic, and power multiplicative. The particular performance indicator is determined as a relation between actual and normative values for the Russian Federation’s Central District’s regions. The investigation’s information base was statistical data on the regions of the RF CFD for 2007–2016. The issues under discussion are differences in results of evaluation obtained in using the first, second and third type models.