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In accordance to the Sustainable Development Goals efficiency in waste management is evaluated on the basis of resource saving and environmental protection. The article presents a study of polymer waste treatment at the enterprise "EcoResourcePovolzhye" in Togliatti, located in the Samara region of the Russian Federation. The technological process with a full cycle allows the company to produce secondary material resources from solid municipal waste. Monitoring of the technological line operation, equipment capacity, calculation of throughput capacity at technological areas of initial raw material processing was performed. Processes at the preparatory stage of primary processing of polymer waste have features. The technological scheme of processing consists of the following operations: sorting and separation of plastic wastes (machine+manual), crushing (shredding), agglomeration (plasticization) and pelletizing, ets. Material balance method of planning technological transitions of raw materials indicated insufficient capacity and technical imperfection of the technological crushing section. Researches have allowed choosing the most optimal technological installation for increase in volume of primary processing of polyethylene wastes. As a result of implementation of new technique the production losses were reduced, the productivity at the critical section was increased. This made it possible to increase the volume of plastic waste recycling as SMR and to state the technological efficiency of the works performed. The environmental effect of reducing the amount of waste disposal at the landfill was obtained. The economic effect in the form of additional profit was determined due to the increase in the scale of sales of demanded products. [ABSTRACT FROM AUTHOR]

The work is devoted to the review of the possibility of the use of aluminum matrix composites in the parts of electric rolling stock current collectors. The possibility of using composite materials in the parts and the units of current collectors operating in conditions of high current loads and at high speed is analyzed. The static analysis using a finite element method in SolidWorks Simulation is performed. The strength performance of the parts of the conventional pantograph head suspension and composite pantograph head suspension is compared. The multibody modeling using SolidWorks Motion has been performed to analyze the dynamic characteristics of the composite head suspension with an aluminum matrix and its effort on the dynamic characteristics of the pantograph. The obtained results evidence an improvement of the dynamic characteristics of the composite head suspension and its positive effect on the dynamic characteristics of the pantograph. [ABSTRACT FROM AUTHOR]

One of the important tasks of agriculture is to increase the milk productivity of cattle and improve the quality of the products obtained. The main factor in solving this problem is to provide the right balanced feed for animals, including silo, one of the succulent feeds. The prospects for the development of dairy cattle breeding largely depend on the provision of high-quality feed. Provision of own production feed, which has a positive effect on the economy, strengthening the forage base, the problem of preserving and improving the quality of feed and ensuring the safety of their nutrients remain one of the important urgent tasks of agriculture. Silo plays an important role in the organization of full-fledged feeding, because the lack of succulent feed in the diet leads to overspending of concentrated feed. The availability of high-quality raw materials, the use and observance of the silo harvesting technology can guarantee the receipt of the highest quality feed. The purpose of the research work is to study the technology of silo production on the farm, as well as to study the quality of harvested silo and its safety for animal health in Yakutia. To solve the purpose of the work, the following tasks were set to obtain and control the safety of the silo: to study the technology of harvesting silage; familiarize yourself with the methods for assessing the quality of silage; carry out a veterinary and sanitary assessment of silo samples. [ABSTRACT FROM AUTHOR]

One of the many construction problems at present is that large areas are composed of weak water-saturated soils and have complex behavior under seismic influences. During an earthquake, non-standard processes can occur at the base, including soil liquefaction, which negatively affects the dual work in the "base - foundation - structure" system. In such conditions, pile foundations are widely used due to several advantages. However, their behavior during the liquefaction of the surrounding soil has not yet been adequately studied. It is known that the reinforcement of the base with vertical elements, such as piles, is one of the most effective ways to increase the strength and deformation properties of weak soils. Reinforced massifs are also often used in seismic regions. However, the process is still poorly understood in the case of soil liquefaction due to the passage of seismic waves through the ground. Using the modern soil model - PM4Silt, which was developed in 2018, a geotechnical task is set in this paper, in which the behavior of the "base - foundation - structure" system during liquefaction of the upper soil layer, and also for two variants of foundations is considered. The foundation in the first variant is a classic pile foundation. In the second variant, a slab foundation is used on a base reinforced with vertical piles, the characteristics of which coincide with the piles in the first variant. The main goals of the calculations were to get the difference in the resulting deformations of the base, internal forces in the structures and understand whether the use of different types of foundations contributes to the picture of the liquefaction of the upper layer. The results show significant differences between the two foundation variants when using the PM4Silt model, as well as the dependence of the position of the soil liquefaction points on external factors. [ABSTRACT FROM AUTHOR]

A large number of power systems allow the construction of semi-Markov models. In the process of system operation, for which the semi-Markov model is built, there arise the tasks to correct the model, to estimate the characteristics of the system and to predict its states on the basis of information (vector of signals) obtained during the operation of the system. To solve these tasks, one can use the apparatus of the hidden Markov models theory. The paper considers a hidden Markov model built on the basis of a semi-Markov model of a duplicated system obtained as a result of stationary phase merging of a superposition of two alternating renewal processes. Various types of signals obtained during the operation of the system are considered, and an analysis of the influence of various types of signals on the estimation of the duplicated system characteristics is carried out. [ABSTRACT FROM AUTHOR]

Semi-Markov and hidden Markov models are a widespread tool for modeling stochastic systems. The state codes of the semi-Markov model contain important information necessary to describe the functioning of the system, but it is not always possible to obtain it completely. In particular, it is possible to obtain some signal (information) associated with a semi-Markov process. In this case, the states of the semi-Markov model are not observed (hidden). On practice, we are dealing with a certain vector of signals obtained as a result of the system operation. Consequently, there are problems of correcting the model, analyzing the dynamics of the modeled system and predicting its states on the basis of the received vector of signals. The problems described above can be solved using the apparatus of the theory of hidden Markov models. In this work, a hidden Markov model is built on the basis of a control system semi-Markov model for hidden failures of a technological cell. It is used to solve the problems of evaluating the characteristics of a semi-Markov model, analyzing its dynamics and predicting states based on the vector of signals obtained during the system operation. The constructed hidden Markov model makes it possible to expand the possibilities of semi-Markov model using, in the presence of variables in it that cannot be observed directly. [ABSTRACT FROM AUTHOR]

This paper investigates integrating model representation descriptions in the form of charts and specifications at the stage of automated systems infological modeling, developed in order to solve design tasks on the methodology for automating intellectual labor (MAIT). In the process of creating the automated system on the basis of MAIT there were developed the following model representations: initial, conceptual, infological and datalogical. The infological model representation is invariant to the software and hardware environment and implementation means. The description of infological model representation includes the following forms (specifications) and charts: for a static component – P1 and P2, the chart of infological structure; for a dynamic component – P3 and P4, the chart depicting a system of subject accesses; for a functional component – P5 and P6, the chart depicting a system of subject manipulations; P8 and the matrix chart showing the model as a whole, including static, functional and dynamic components coordination. The features of building diagrams and the formation of specifications when creating an infological structure are investigated, on the basis of which a method and technique for integrating descriptions of static components for model-projects of automated systems that perform computational tasks in the design of mechanical engineering objects are determined. The article provides the integration of descriptions in the form of diagrams and specifications for the static components of infological model views. [ABSTRACT FROM AUTHOR]

This article describes the results of a study of the accuracy of internal threads formed using the FDM technology and additionally machined with taps. For the study, a 3D model of the sample was created, containing internal threads, the geometric parameters of which correspond to ISO 68-1:1998/AMD 1:2020 and ISO 965-1:2013, ISO 965-3:1998 /Cor 1:2009. Based on this model, control programs were created for printing samples from ABS, PETG and PLA - plastics. The samples were printed using a MakerBot MethodX 3D printer. To study the profiles formed in the samples, internal threads, part of the material was cut from the samples along the axes of the threaded holes. The thread profiles in the cut samples were examined using a LIM-1 microscope. With this microscope, photographs of the thread profiles were taken at 50x magnification. [ABSTRACT FROM AUTHOR]

The article discusses the issue of modeling the driving cycle of a vehicle with a hybrid powerplant of a parallel flow type using the Simulink program. The results of modeling the movement of the UAZ-3153 vehicle with a hybrid power plant of a parallel type are presented on the example of the European driving cycle NEDC. Fuel economy is obtained when the vehicle is moving with a periodic transition from an internal combustion engine to an electric motor. At the initial moment of time (0 ... 60 s) there is a sharp jump in fuel consumption, because the vehicle is stationary with the internal combustion engine on. [ABSTRACT FROM AUTHOR]

Consideration is given to the setup and results of shock-wave experiments that recorded the longitudinal stress-wave profiles σxx in quartzite at the initial density ρ0 = 2.63 g/cm³. Profiles of the symmetric impact-induced stress waves were measured within 20–50 GPa by the method of the overtaking release wave in plane samples using manganin gauges built into quartzite. The objective of this effort is to measure experimentally the shock-wave properties of the rock, namely quartzite, as these results are needed to calibrate, further develop, and improve computer models of equations of state. This effort is of fundamental nature. Our task was to generate, with the help of low-resistance manganin gauges, profiles of longitudinal stresses σxx in quartzite sampled from the Pervouralsk deposit. Experiments were performed with the help of plane-wave generators and a two-stage light-gas gun. As a result, a series of experiments provided experimental “longitudinal stress – time” relations and the parameters of quartzite shock compression within 20–50 GPa, both being of great importance for the development of computer models. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the dynamic properties of a structural material, such as stainless steel made by additive fabrication (3D printing). In the study, the split Hopkinson pressure bar system is applied. This method allows us to test a wide range of materials and to study the dynamic diagrams of compression and strain within the strain rate range of ε˙ = 10²–10³ s−1. Specimens made of stainless steel (analogous to the 12Kh18N10T steel) are obtained by laser sintering of metal powder (Selective Laser Sintering) using an industrial 3D printer. Twelve experiments are conducted with the stainless steel specimens. The impactor velocities range from 7 to 14 m/s. The intrinsic strain rates of the specimens range from 0.75×10³ to 2.8×10³ 1/s. The study offers stress–strain and strain-rate –strain diagrams. The objective of the work is to study the properties of stainless steel specimens fabricated by additive techniques. The following tasks are to be solved: determining the strength characteristics of the specimens made of additive stainless steel in a set of experiments using the split Hopkins pressure bars technique; comparing the strength properties of additive stainless steel and its analogue, e.g. the conventional 12Kh18N10T steel. [ABSTRACT FROM AUTHOR]

The study was undertaken in order to obtain experimental data on shock compression of structural materials for the development and refining computational models of material and structure behavior under shock wave loading. Wave profiles of longitudinal stresses σxx in stainless steel of a specified grade were measured at the initial density ρ0 = 7.89 g/cm³. The stress wave profiles were measured using symmetric impact by the method of overtaking unloading wave in flat samples with the help of manganin sensors built in the metal or the buffer material. Sound velocities in shock-loaded stainless steel were determined using the obtained profiles σxx(t). Experimental data on sound velocities C(σ¹xx) vs. stress in a shock wave σ¹xx are provided. As a result of a series of experiments, experimental data on sound velocities in shock-loaded stainless steel of grade 12Cr18Ni10Ti were obtained in the range of initial values of shock compression of 10 ≤ σ¹xx≤88 GPa. [ABSTRACT FROM AUTHOR]

The study is undertaken in order to obtain experimental data on dynamic compression of structural materials for refining computational models that describe material behavior under dynamic loading. The task was to study the dynamic properties of a copper-tin alloy and copper M00K in the strain rate range ε = 10² − 104 s-1 [ABSTRACT FROM AUTHOR]

The current work is devoted to the study of fatty acid carboxylic group hydrogenation in order to obtain fatty alcohols which are the valuable products for fine chemistry. The catalysts based on the ruthenium impregnated into hypercrosslinked polystyrene (HPS) were used in the process. The influence of the type of the support and metal loading on the yield of hydrogenation products was evaluated. Three different types of HPS were used as the catalyst supports non-functionalized, modified with amino- and sulfonic groups. Ru embedded on the HPS modified with amino groups showed a high yield of stearyl alcohol (86.5%) at high substrate conversion (90%). The catalyst based on HPS modified with sulfonic groups showed good selectivity towards the formation of stearic aldehyde, however, was found to be unstable under the reaction conditions. The analysis of the results showed that Ru-containing catalysts can be concerned the permissive in the carboxylic group reduction of fatty acids. 1%Ru/MN100 showed was found to be the most effective catalyst remaining its activity at minimum 5 multiple reuses. [ABSTRACT FROM AUTHOR]

The experimental and theoretical research carried out in the past at the Institute of Applied Physics (IAP RAS) resulted in development of a new type of electron cyclotron resonance ion source (ECRIS) - the gasdynamic ECRIS. The gasdynamic ECRIS features a confinement mechanism in a magnetic trap that is different from Geller's classical ECRIS confinement i.e. the quasi-gasdynamic one similar to that in fusion mirror traps . Such ion source type has demonstrated good performance producing high current (100-300 mA) multi-charged ion beams with moderate average charge (Z=4-5 for argon) and especially high efficiency for low emittance hydrogen and deuterium beam formation (500 emA current, current density up to 700 emA/cm2 and RMS emittance below 0.07 π·mm·mrad). Experimental studies of gasdynamic ECRIS in a pulsed mode were performed at SMIS 37 facility.The obtained high-level results have stimulated a wide spectrum of research activities devoted to further extension of the gasdynamic ECR source principles to related fields of research and applications. The present report overviews recent investigations at the Ion Sources Laboratory connected with ECR plasma heating by powerful millimeter wave gyrotron radiation. Novel ideas such as using a magnetic field generated by a single coil for plasma quasigasdynamic confinement for proton beams production, applications of a dense ECR plasma for H- generation, development of a new CW gasdynamic ECR source with 28 GHz gyrotron heating among others are discussed. [ABSTRACT FROM AUTHOR]