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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.

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.

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).

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.

Industrial dust is one of the most common harmful factors in the working environment. Because of it, equipment can fail. When inhaled, it has a negative effect on health and can lead to specific diseases. It reduces visibility in the production area. The aim of the study is to achieve the necessary environmental effect that ensures a decrease in the amount of harmful emissions in the working area, i.e. the ecological effect can be determined by the amount of pollutants, the spread of which is prevented as a result of the installation of highly efficient technological equipment specially designed for these purposes.

With the wrong use of antibiotics for agricultural poultry, the effectiveness of their effect on the body is noticeably reduced, since pathogenic and conditionally pathogenic microorganisms become resistant to them for a certain time, i.e., there is a process of “addiction“. Experience shows that enrichment of feed rations with enzyme preparations and vitamins improves the functioning of the stomach and intestines, increases the natural resistance of the body, as a result of which the mortality of poultry decreases, the absorption of feed is significantly increased and their costs per unit of production are reduced. We studied the effect of the new vitamin-enzyme complex Vitaferm on the organism of broilers against the background of the exclusion of antibacterial drugs from the antiepizootic measures scheme and compared its effect with the enzyme preparation Avizim 110. The studies carried out indicate the positive effect of Vitafarm and Avizim 110 on the poultry organism, which is manifested by an increase in average daily poultry gains, an increase in safety, and a decrease in feed costs per unit of production. These changes can be explained by the normalization of the gastrointestinal tract of broiler chickens and increased immunity. Antibiotics suppress the body’s immune system; upset the balance of the intestinal microflora. For the complete or partial exclusion of antibacterial drugs from the scheme of antiepizootic measures, it is proposed to apply to broiler chickens with feed the vitamin-enzyme complex of Vitaferm at the rate of 15.0 g / kg starting from day old for 10 days.

Modern global controversy can be characterized through a diversity of methods, tools, forms and instruments. Scientific community carries on research in this sphere. In contemporary discourse the notion of “political infantry” is widely used. The expediency and justification of the usage of this notion is analyzed in the following article.