bluuebunny/crossref_metadata_2025 huggingface dataset:
IgG and IgA Antibodies Post SARS-CoV-2 Vaccine in the Breast Milk and Sera of Breastfeeding Women
Authors: Scrimin Federica , Campisciano Giuseppina , Comar Manola , Ragazzon Chiara , Davanzo Riccardo , Quadrifoglio Mariachiara , Giangreco Manuela , Stabile Guglielmo , Ricci Giuseppe
Published: January 2022

The COVID-19 pandemic has carried massive global health and economic burden that is currently counteracted by a challenging anti-COVID-19 vaccination campaign. Indeed, mass vaccination against COVID-19 is expected to be the most efficacious intervention to mitigate the pandemic successfully. The primary objective of the present study is to test the presence of neutralizing anti-SARS-CoV-2 antibodies (IgA and IgG) in the breast milk and sera samples from vaccinated women at least 20 days after the complete vaccine cycle. A secondary aim is to compare the IgG antibodies level in maternal serum and breast milk. The third target is to evaluate the presence of the IgG antibodies in breast milk after several weeks from the vaccination. Finally, we collected information on the health status of infants in the days following maternal vaccination. Forty-two mothers were enrolled in the study. Thirty-six received the Pfizer/BioNTech vaccine, four the Astra Zeneca vaccine, one the Moderna vaccine and another woman Astra Zeneca in the first dose and Pfizer/BioNTech in the second dose. All 42 milk samples confirmed the presence of anti-SARS-CoV-2 IgG, and none showed IgA presence. Regarding the matched 42 sera samples, 41 samples detected IgG presence, with one sample testing negative and only one positive for seric IgA. None of the 42 infants had fever or changes in sleep or appetite in the seven days following the maternal vaccination. The level of IgG antibodies in milk was, on average, lower than that in maternal serum. According to our analysis, the absence of IgA could suggest a rapid decrease after vaccination even if frequent breastfeeding could favour its persistence. IgG were present in breast milk even 4 months after the second vaccine dose. Information on the immunological characteristics of breast milk could change mothers’ choices regarding breastfeeding.
European Mistletoe (Viscum album) Extract Is Cytotoxic to Canine High-Grade Astrocytoma Cells In Vitro and Has Additive Effects with Mebendazole
Authors: Wright Anna , Watanabe Rie , Koehler Jey W.
Published: January 2022

Malignant gliomas are associated with extremely poor clinical outcomes in both humans and dogs, and novel therapies are needed. Glioma-bearing canine patients may serve as promising preclinical models for human therapies, including complementary medicine. The objective of this study was to evaluate the effects of mistletoe extract (Viscum album) alone and in combination with mebendazole in an in vitro model of canine high-grade astrocytoma using the cell line SDT-3G. SDT-3G cells were exposed to a range of concentrations of mistletoe extract alone to obtain an IC50. In separate experiments, cells were exposed to mebendazole at a previously determined IC50 (0.03 µM) alone or in conjunction with varying concentrations of mistletoe extract to determine the additive effects. The IC50 for mistletoe alone was 5.644 ± 0.09 SD μg/mL. The addition of mistletoe at 5 μg/mL to mebendazole at 0.03 µM led to increased cell death compared to what would be expected for each drug separately. The cytotoxicity of mistletoe in vitro and its additive effect with mebendazole support future expanded in vitro and in vivo studies in dogs and supply early evidence that this may be a useful adjunct therapeutic agent for use in glioma-bearing dogs. To the authors’ knowledge, this is the first published report of Viscum album extract in canine glioma.
Application of Artificial Neural Networks for Mangrove Mapping Using Multi-Temporal and Multi-Source Remote Sensing Imagery
Authors: Ghorbanian Arsalan , Ahmadi Seyed Ali , Amani Meisam , Mohammadzadeh Ali , Jamali Sadegh
Published: January 2022

Mangroves, as unique coastal wetlands with numerous benefits, are endangered mainly due to the coupled effects of anthropogenic activities and climate change. Therefore, acquiring reliable and up-to-date information about these ecosystems is vital for their conservation and sustainable blue carbon development. In this regard, the joint use of remote sensing data and machine learning algorithms can assist in producing accurate mangrove ecosystem maps. This study investigated the potential of artificial neural networks (ANNs) with different topologies and specifications for mangrove classification in Iran. To this end, multi-temporal synthetic aperture radar (SAR) and multi-spectral remote sensing data from Sentinel-1 and Sentinel-2 were processed in the Google Earth Engine (GEE) cloud computing platform. Afterward, the ANN topologies and specifications considering the number of layers and neurons, learning algorithm, type of activation function, and learning rate were examined for mangrove ecosystem mapping. The results indicated that an ANN model with four hidden layers, 36 neurons in each layer, adaptive moment estimation (Adam) learning algorithm, rectified linear unit (Relu) activation function, and the learning rate of 0.001 produced the most accurate mangrove ecosystem map (F-score = 0.97). Further analysis revealed that although ANN models were subjected to accuracy decline when a limited number of training samples were used, they still resulted in satisfactory results. Additionally, it was observed that ANN models had a high resistance when training samples included wrong labels, and only the ANN model with the Adam learning algorithm produced an accurate mangrove ecosystem map when no data standardization was performed. Moreover, further investigations showed the higher potential of multi-temporal and multi-source remote sensing data compared to single-source and mono-temporal (e.g., single season) for accurate mangrove ecosystem mapping. Overall, the high potential of the proposed method, along with utilizing open-access satellite images and big-geo data processing platforms (i.e., GEE, Google Colab, and scikit-learn), made the proposed approach efficient and applicable over other study areas for all interested users.
Groundwater Nitrate Pollution Sources Assessment for Contaminated Wellfield
Authors: Šrajbek Marko , Kranjčević Lado , Kovač Ivan , Biondić Ranko
Published: January 2022

Nitrates are one of the most common groundwater contaminants and they come from different sources. The paper presents a study of groundwater quality at Varaždin wellfield in the north part of Croatia. The nitrate concentration at this location has been above the maximum allowed concentration for several decades, which has made the opening of new wellfields costly. Based on the previously developed groundwater flow model, a model that covers the narrow area of the wellfield is developed. The influential zone of the observed wellfield in working conditions is determined. Based on the developed model, the sources of nitrate pollution are located, which can be generally divided into non-point and point sources. Considering the time of groundwater retention in the horizontal flow, it is concluded that the water protection zones are marked following the applicable ordinance. Based on the developed groundwater flow model at the observed wellfield, a simulation of nitrate pollution propagation by advection and dispersion processes is performed. The simulation results point out the location of the poultry landfill as the largest source of nitrate pollution. However, poultry farms, which are located in the influence area of the wellfield, also contribute significantly to the nitrate concentration at the wellfield.
Review of a Semi-Empirical Modelling Approach for Cohesive Sediment Transport in River Systems
Authors: Krishnappan Bommanna
Published: January 2022

In this paper, a review of a semi-empirical modelling approach for cohesive sediment transport in river systems is presented. The mathematical modelling of cohesive sediment transport is a challenge because of the number of governing parameters controlling the various transport processes involved in cohesive sediment, and hence a semi-empirical approach is a viable option. A semi-empirical model of cohesive sediment called the RIVFLOC model developed by Krishnappan is reviewed and the model parameters that need to be determined using a rotating circular flume are highlighted. The parameters that were determined using a rotating circular flume during the application of the RIVFLOC model to different river systems include the critical shear stress for erosion of the cohesive sediment, critical shear stress for deposition according to the definition of Partheniades, critical shear stress for deposition according to the definition of Krone, the cohesion parameter governing the flocculation of cohesive sediment and a set of empirical parameters that define the density of the floc in terms of the size of the flocs. An examination of the variability of these parameters shows the need for testing site-specific sediments using a rotating circular flume to achieve a reliable prediction of the RIVFLOC model. Application of the model to various river systems has highlighted the need for including the entrapment process in a cohesive sediment transport model.
Implementation of innovative measures with a purpose improving the quality of nursing care
Authors:   SBHI «Samara Regional Clinical Cardiological Dispensary named after V.P. Polyakov», Glazkova Evgenia Ivanovna , Inozemtseva Svetlana Vladimirovna ,   SBHI «Samara Regional Clinical Cardiological Dispensary named after V.P. Polyakov»
Published: January 2022

The article presents the experience of optimizing the provision of nursing care and nursing care in a cardiological dispensary. The article considers the introduction into practice of the «effective contract», as one of the innovative methods of nursing staff management and improving the quality of management activities. The importance and expediency of using the criteria for assessing the quality of the work of nursing personnel for an adequate assessment of the work of each employee individually was emphasized.
Instrumental diagnosis of cholesterol polyps of the gallbladder
Authors:   Department of Hospital Surgery, FSBEI HE Moscow State University of Medicine and Dentistry named after A.I. Evdokimov of the Ministry of Health of Russia,  Surgical Department, Bakhrushin Brothers City Clinical Hospital of the Moscow Healthcare Department, Nikolaev Dmitriy Vladimirovich , Gavrilova Aleksandra Sergeevna ,   MMU «Reaviz», Grozina Elena Olegovna ,   MMU «Reaviz»
Published: January 2022

Gallbladder polyposis is a common pathology, the detection of which has increased significantly in recent years. The dominant form of this disease is cholesterol pseudopolyps, mainly found inwomen. Clinical manifestations of gallbladder cholesterol polyps are nonspecific,which presents certain difficulties in diagnosis.Ultrasonography is one of themost informative and accessible instrumental diagnostic methods.
January 26 — International Day «Let's Talk»
Authors:   SBHI RK Kerch City Children's Hospital, Rybachok Oksana Aleksandrovna
Published: January 2022

January marks the beginning of the new year and the middle of winter, therefore, the holidays this month are celebrated accordingly, for example, in Canada and the United States, Walrus Day is celebrated on January 1 with the organization of traditional swims in ice water, but on January 5, it was proposed to celebrate Fasting Day, obviously, with the purpose of saving the body tired from the festive feasts. On January 14, in some countries, it is customary to celebrate an unusual day — the Day of Combating Procrastination, which in psychology means «constantly putting things off for later», some experts have already dubbed this fairly common feature «the disease of the 21st century». January 16 isWorld SnowDay and January 21 is International Hug Day. Besides, on the last Wednesday of January, concerned people proposed to establish Let's Talk Day, dedicated to the problem of difficult relationships between healthy people and patients with mental disorders. Canada was the initiator of the celebration of this day. Experts suggest that ordinary people protect themselves from mental illness by leading an active lifestyle, but does it always help? Let's try to figure it out in this article.
Breed-specific SNP markers of beef productivity of cattle of Kazakh White-headed breed
Authors:   State Pedagogical University named after Maxim Tank, Republic of Belarus, Minsk, Belaya Belarusian E. V. , Kovalchuk A. M. ,   Nonprofit AO «Zhangir Khan West Kazakhstan Agrarian Technical University», Republic of Kazakhstan, Uralsk, Beishova I. S. ,   Nonprofit AO «Zhangir Khan West Kazakhstan Agrarian Technical University», Republic of Kazakhstan, Uralsk
Published: January 2022

One of the most promising modern methods used to identify loci that control quantitative traits of productivity in cattle is the method of Genome-wide association of (GWA), which makes it possible to establish a link between allelic variation in a certain region of the genome and the trait under study. The purpose of the research was to establish breed-specific SNP markers of beef productivity of cattle of Kazakh white-headed breed. The results of the search for breed-specific genetic markers of increased beef productivity for Kazakh White-headed breed based on the data of DNA typing of animals using the GGP Gene Search chip Cattle 150 thousand (Illumina Inc., USA) have been presented. Genotyping data processing for each SNP and each sample was performed using the PLINK 1.9 software package (http://zzz.bwh.harvard.edu/plink/). The search for unique regions of the genome has been carried out by using homozygosity rows (ROH). Homozygosity rows (ROH) have been evaluated for each animal using the QTL database of Cattle PLINK. Seven SNP markers of increased beef productivity have been identified in Kazakh White-headed cattle: allele C (rs109910863) in the histatherin gene (histatherin (HSTN)), allele C (rs110065568) in the myostatin gene (myostatin (MSTN)), allele g (rs110320975) in the histatherin gene (histatherin (HSTN)), allele C ( rs135748641) in the gene of a nucleolar protein interacting with the domain of risk factor MKI67 (nucleolar proteins interacting with FCA domain MKI67 (NIFK), allele g (rs136552787) in the gene of insulin-like factor 6 binding protein (protein, binding insulin-like growth factor 6 (IGFBP6-202)), allele A (rs137243785) in the histatherin gene (histaterin (HSTN-201)), allele A (rs522351439) in the myostatin gene (myostatin (MSTN)).
Economic analysis of the world export of educational services
Authors:   Department of the International and Foreign Trade of the Russian Federation, Russian Foreign Trade Academy of Ministry of Economic Development of the Russian Federation, Russia, Moscow, Rodigina Natalya Yurievna , Musikhin Vladislav Igorevich ,   Department of World and National Economy, Russian Foreign Trade Academy of Ministry of Economic Development of the Russian Federation; Transneft ElektrosetServis LLC, Russia,, Azarova Ofeliia Andranikovna ,   Department of English Language and Professional communication, Financial University under the Government of the Russian Federation, Russia, Moscow, Logina Maria Vladimirovna ,   Financial University under the government of the Russian Federation, Russia, Moscow
Published: January 2022

The research looks at the export of educational services as one of the promising spheres for the development of international economic relations. The study focuses on the experience of developed supplier and recipient countries. The theoretical basis of the study is formed by the typology of ways to export services proposed in the General Agreement on Tariffs and Trade. The importance of the issue under consideration is due, among other things, to the fact that, according to forecasts, the number of foreign students wishing to obtain higher education will increase to 150 million in 2025, and the volume of exports of higher education will reach $30 billion, which is 3 % of the total volume of trade in OECD services. Most prior research focuses on methodological aspects of education; however, the experience of foreign countries is presented in a limited scope. Using the example of the USA in the context of the management training program, it is shown that a fairly broad methodological system is used abroad, allowing specialists from all over the world to acquire the necessary skills and develop competencies. It is obvious that the pandemic has led to a sharp reduction in the number of foreign students in Germany, as in other exporting countries of educational services. Of particular interest is the EdTech market, which is attractive in terms of its size and growth rates. The key barriers to the global market of educational services are, among other things, increased competition, the presence of a larger number of exporters-providers of educational services, more active classes at mass open online courses, active use of mobile devices; the use of learning models that include personalized and blended learning methods; increasing the degree of confidentiality of data; active development of the institute of continuing education in conjunction with the active use of advanced training courses and vocational training. The research is expected to provide valuable information about the balance of powers on the global market of educational services and will serve as an information base for further scientific research in the field.
ALGORITHM FOR OPTIMIZING THE PARAMETERS OF OIL PIPELINES WHEN DESIGNING PETROCHEMICAL INDUSTRY EQUIPMENT
Authors: KHVOSTOV A.A. , ZHURAVLEV A.A. , TATARENKOV Е.А. , TKACHEV О.А.
Published: January 2022

The problem of technical and economic optimization of pipeline parameters for transportation of petroleum products exhibiting a viscosity anomaly is considered. The relations for determination of optimal pipeline diameter and pressure, providing pumping of the medium in the laminar, steady, isothermal regime on the pipeline from the condition of minimizing the total annual cost of its development and operation based on current prices and tariffs for the pipeline and energy topology of the pipeline, its working conditions, as well as anomalies of the viscosity of the transported medium.
TEMPERATURE-VISCOSITY WEDGE CONTROL IN A FLUID FRICTION BEARING BASED ON A DEEP REINFORCEMENT LEARNING ALGORITHM
Authors: KORNAEV A.V. , KORNAEVA E.P. , KAZAKOV Yu. N. , BABIN A.Yu.
Published: January 2022

. This paper discusses the possibility of using intelligent systems based on reinforcement learning and deep neural networks to control the lubrication system of a mechatronic fluid friction bearing. The training of the agent of the control system was carried out on a simulation model of a rotary machine, the purpose of training was to reduce energy losses for friction and reduce the level of vibrations under conditions of a random external force action of a periodic nature with a random frequency. The ability to switch modes has reduced the negative effect of the resonance phenomenon. The results of the training demonstrated the effectiveness of using such intelligent systems for the developed mechatronic bearing arrangement.
EXPERIMENTAL STUDY OF THE DEVELOPED COLOMETRIC SENSOR FOR MEASURING THE COLOR OF GLASS
Authors: AREFYEV A.V. , GULIYEV R.B. , DAGAEV A.V. , MAIOROV E.E. , PISAREVA E.A. , KHOKHLOVA M.V.
Published: January 2022

This article to the study of a colorimetric sensor for measuring the color parameters of transparent and diffusely reflecting objects is devoted. This paper a colorimetric sensor that uses a three-element RGB photodiode is presented. The block diagram and appearance of the developed sensor are shown. The operation of the colorimeter is described, and the spectral sensitivity of the RGB photodiode is obtained. Specially developed software for obtaining measurements in digital and graphical form is presented. The metrological capabilities of the colorimetric sensor by comparing the obtained measurement results with independent data were investigated. Optical color glasses of the following brands were used for calibration: KS-11; ZHZS-17; SS-2; ZS-4; ZHS-12; PS-7; OS-13, the color coordinates of which were located inside the color triangle. The results of calibration of the colorimeter and test measurements of the chromaticity coordinates of the samples on the color triangle were shown. In research, the developed colorimetric sensor measurement of the color parameters of transparent objects with a range of readings that characterizes a random error of no more than 0,3 % was provided.
DESIGN AND ANALYSIS OF PREDICTIVE MODELS OF DANGEROUS TECHNICAL STATE OF MACHINE-BUILDING PRODUCTS
Authors: OSIPOV K.N.
Published: January 2022

An approach to the design of adaptive empirical multidimensional mathematical predictive models based on the results of measurements used to assess the risk of transition of technically complex products to a dangerous technical condition during production (acceptance and control) tests is proposed. The issues of verification and evaluation of the speed of adaptation of the proposed models to changing conditions and test goals are considered. As an example, we consider the process of modeling and forecasting changes in the technical conditions of high-speed internal combustion engines with forced spark ignition.
STRESS-STRAIN STATE OF AN UNLOADED RIVET JOINT OBTAINED BY THE HOT METHOD
Authors: LEONTYEV V.V. , KONDRATOVA E.V. , KOLOMIYCHENKO V.P.
Published: January 2022

A method for creating a rivet connection using hot riveting is considered. A rivet heated to a temperature of 900 С is placed in a cylindrical hole in the plates at room temperature. When cooled to room temperature, the rivet is subjected to thermal compression and creates a tight fit. The elastic-plastic contact heat-strength problem for such a compound in the COMSOL MULTIPHYSICS software package was solved using the finite element method. The problem is solved in a three-dimensional statement. The first stage is the temperature distribution in the rivet-sheet system. The resulting temperature field is used as a parameter at the second stage when solving the strength problem. The fields of residual stresses in the connection parts are obtained. It is shown that the equivalent stresses are close to the ultimate strength of the material of these parts. The analysis of axial stresses confirms the possibility of creating a tight connection by hot riveting. Recommendations for calculating the strength of such compounds are given.
ANALYSIS OF COMPLEX DETAIL FINISHING TEMPORARY CHARACTERISTICS
Authors: NEMENKO A.V. , NIKITIN M.M.
Published: January 2022

Estimation of the time characteristics of the process of finishing a complex product is considered: the average time for an operation and the average time for reconfiguring according to the characteristics of their elements. For this, the work uses the mathematical apparatus of the theory of reliability. It is shown that the results obtained, based on the use of distribution functions, tend in the limit to the results of semi-Markov models using average values.
FORECAST EVALUATION OF A COMPLEX MECHANICAL SYSTEM TECHNICAL STATE
Authors: NEMENKO A.V. , NIKITIN M.M.
Published: January 2022

A method is proposed for estimating of a mechanical system technical state by its element that requires priority replacement at a selected future point in time, in the case of specifying quantitative indicators of reliability in the form of a time series. The method is applicable both for serial-parallel systems and for the general case of connecting elements along a complete graph, the special cases of which can be represented by all other methods of the reliability analysis scheme. To predict the state of each element, an approximation is used.
ACCURACY OF LINEAR DIMENSIONS IN SHEET METAL BENDING
Authors: SAFRONOV E.V. , NOSKO A.L. , BELENCHUK R.L.
Published: January 2022

The article is devoted to the problem of ensuring the accuracy of manufacturing parts by sheet metal V-bending. An example of using bending in the manufacture of a roller conveyor part is shown. Manufacturing inaccuracy occur due to the deviation of the sheet thickness from its nominal value. A method for determining the maximum inaccuracy of the linear dimensions of the bend depending on the maximum deviation in the thickness of the sheet, based on the difference in the length of the plain workpiece at the nominal and actual values of the sheet thickness, is given. The calculation of the inaccuracy of linear bending dimensions for cold-rolled sheets of normal accuracy BT and hot-rolled sheets of normal accuracy B with a width of 1 to 1.5 m and a thickness of 1 to 15 mm is given. It is shown that the accuracy of each bend for cold-rolled sheets is within ±0.18...±0.38 mm; the accuracy of hot-rolled sheets is ±0.35...+1.32/-0.58 mm.
THE MODERN LASER METHODS OF MACHINE AND TOOL PARTS HARDENING ANALYSIS
Authors: KOLOSOVSKIY A.M. , TRISTANOVA E.B. , CHERKASHINA E.F.
Published: January 2022

The article offers a retrospective analysis of the development of laser and combined lasers based on the use of laser radiation methods of hardening the responsible parts of machines and tools. It is shown that the combination of laser radiation and other advanced technological methods creates contact surface layers of machine with unique physical-mechanical and operational properties forming is the current and promising direction in an improving technologies for their application with high physical and mechanical properties of responsible parts.
NUMERICAL SIMULATION OF STEEL WIRE DRAWING
Authors: LEONTYEV V.V. , KOLOMIYCHENKO V.P.
Published: January 2022

Using the ANSYS program, the stress-strain state of steel wire in the drawing process is investigated by the finite element method. The problem of plastic flow of metal in a conical matrix-fiber is solved. The problem statement is axisymmetric for different positions of the wire relative to the matrix. The fields of radial stresses, axial stresses and equivalent plastic deformations are obtained. The results allow us to proceed to the study of the influence of various drawing parameters on the stress state of the wire. This will make it possible to optimize the drawing process and offer new drawing designs and lubrication methods that reduce wear and increase the service life of this tool.
DEVELOPMENT OF THE OPTIMAL LAYOUT OF THE EQUIPMENT IN THE DIVISIONS OF THE BODY-PROCESSING SHOP
Authors: CHEMAKINA T.L. , SEMENENKO S.A.
Published: January 2022

The issues of improving the technology of shipbuilding and ship repair production in order to increase the volume of products and improve their quality, depending on the level of the technical base of production, are presented.
APPLICATION OF THE DEFORM SOFTWARE FOR MODELING THE DRILLING PROCESS OF COMPOSITE MATERIALS BASED ON THE FINITE ELEMENT METHOD
Authors: PODVINTSEV A.V. , DUDAREV A.S.
Published: January 2022

This article shows the solution of a complex related problem of numerical simulation of the drilling process of polymer composite materials based on the finite element method (FEM), using the Deform engineering package. The subject of the study in setting the tasks was the functional characteristics of the drilling process: the components of the cutting force, the temperature in the cutting zone, depending on the different combination of controlled parameters of the processing mode and the geometric parameters of the drills, taking into account the specific properties of polymer composite materials. The value of the axial cutting force during drilling is important, since this value is used to calculate the drive power of technological equipment, check the strength of the cutting tool, and the cutting temperature can predict the quality of the shaped holes. The values of the power and thermal characteristics can be obtained by different methods, theoretical and practical, for example, in the course of a full-scale experiment. But for a full-scale experiment, serious preparation is necessary, the presence of a laboratory base. For a theoretical solution, it is necessary to know and apply the mathematical apparatus or use modern engineering packages. The latter is done in this work.
RESEARCH OF LIQUID RESPIRATION TECHNOLOGY BY THE METHOD OF IMMERSION/ASCENT OF A BIOLOGICAL OBJECT IN A HYDRAULIC CHAMBER WITH HIGH PRESSURE
Authors: POLIVTSEV V.P. , POLIVTSEV V.V.
Published: January 2022

The study of liquid respiration technology for the process of immersion/ascent of biological objects in the stand at depths of 500, 1000 and 1500 m is proposed. Safe modes and the depth of immersion/ascent of biological objects are studied. A hydraulic stand and a capsule for immersion/ascent of a biological object were developed and tested. The main characteristics of a hydraulic stand that simulates diving/surfacing to a depth of 1500 meters are given. Safe diving/surfacing modes and maximum diving depths on the spontaneous breathing of the dog are determined. The results of medical studies of the biological object on such basic parameters of ECG, EEG, ultrasound, X-ray, and other instrumental methods of research are presented.
OPTIMIZATION OF REGENERATION RATIO FOR CYCLES OF GAS TURBINE PLANTS WITH SHELL-TUBE REGENERATORS
Authors: DOLOGLONYAN A.V. , MATVIIENKO V.T.
Published: January 2022

The subject of consideration in the article is a mathematical model of the pressure recovery factors of gas turbine plants (GTP) regenerators, which takes into account the dependence of the hydraulic resistance of the heat exchanger on its surface area and the coefficient of compactness. Optimization of the GTP regenerative cycle and the cycle with a turbocompressor utilizer and regeneration was carried out in order to further increase their efficiency. It has been established that the use of the proposed model of the pressure recovery factors for the air and gas sides makes it possible to find the regeneration ratio that is optimal from a thermal engineering point of view. This model can be used for simplified and preliminary calculations of the GTP.
IMPROVING THE PROCESSES OF INCOMING CONTROL OF METAL POWDER COMPOSITION, SYNTHESIS AND HEAT TREATMENT OF THE Co-Cr-Mo ALLOY FOR USE IN GAS TURBINE ENGINE UNITS
Authors: POLYAKOV S.A. , FEDOROV N.V. , SHATULSKY A.A.
Published: January 2022

Measures were taken to improve the technology of manufacturing of parts of the combustion chamber of the gas turbine engine using additive technologies, including improving the efficiency of the incoming control of the metal powder composition, choosing the technological parameters of the synthesis of parts, assigning the mode of heat treatment and welding of synthesized and traditional materials, which allowed to meet the requirements for mechanical and operational properties.
TECHNOLOGY FOR OBTAINING NEW BIOLOGICALLY ACTIVE PECTIN MATERIALS MODIFIED WITH L-TRIPTOFAN
Authors: KUKOVINETS О.S. , MUDARISOVA R.KH. , VAKULSKAYA A.A. , ISAEVA A.R.
Published: January 2022

New polymer complexes of copper (II) were obtained on the basis of apple pectin modified with the amino acid L-tryptophan. The stoichiometry of the complexes formed was determined by spectrophotometric methods, and the stability constants and standard thermodynamic characteristics of the complexation process (Hº; Gº; Sº) were calculated. It was found that the interaction of pectin modified with an amino acid with Cu (II) cations leads to the formation of enthalpy - entropy stabilized metal complex compounds. The IR spectral method showed that the coordination interaction of copper (II) cations with tryptophan-modified pectin involves not only carboxyl groups, but also the hydroxyl functions of the polymer matrix. The obtained polymer metal complexes in the future can be proposed for the production of new generation drugs, which, in addition to the specific properties of the amino acid introduced into the polysaccharide, also have membranotropic, immunomolulatory properties and prolonged action.
SINGULARITIES OF OPERATION OF MAIN SHIPS ENGINES ON ECONOMICAL MODES
Authors: GOGOLEV G.V.
Published: January 2022

The article considers singularities for operation of main ships diesels in slow economical modes. The effectiveness of the methods for optimizing and safety operation of engines considered in the article is analyze. The advisable solutions is expand.
RISK ASSESSMENT OF EMERGENCY SITUATIONS DURING OPERATION OF INTERNAL COMBUSTION PISTON ENGINES
Authors: OSIPOV K.N.
Published: January 2022

A method for assessing the risk of transition of technically complex objects and systems to an emergency technical state is substantiated, which poses a danger to the operating personnel and material assets. As an illustrative example, the process of assessing the probability of transition to a faulty state of reciprocating internal combustion engines with forced ignition and external mixture formation 4 CH 7.5 / 8.5 based on the results of measuring their diagnostic parameters in real time is considered.
NUMERICAL ANALYSIS OF HYDRODYNAMIC LUBRICATION IN FRICTION PAIR FROM HARD MATERIALS OF A TOTAL HIP JOINT REPLACEMENT
Authors: PAKHALIUK V.I. , POLIAKOV A.M.
Published: January 2022

A numerical analysis of the hydrodynamic lubrication problem in a friction pair of a hip joint replacement with surfaces made of materials with a high modulus of elasticity, such as metal-metal or ceramic-ceramic, under steady-state walking conditions is presented. The Reynolds equation in spherical coordinates has been solved for the movements of the film with a three-dimensional change in the load and speed experienced in a friction pair of the hip joint during walking. It has been shown that a finite lubricating film thickness can be formed during the walking cycle due to the film squeezing. It has also been found that the design parameters of the spherical sliding pair, such as the radius of the femoral head and the radial clearance between the femoral head and the acetabular element, have a large influence on the predicted film thickness. It was concluded that there is a high likelihood that a continuous hydrodynamic lubricating film may be formed in hip replacement with a ceramic-to-ceramic pair and, possibly, for implants with some well-machined metal-to-metal pairs with a relatively small radial clearance that provides completely fluid friction.
ACTUATOR MADE OF MATERIAL WITH SHAPE MEMORY EFFECT FOR DEPLOYMENT OF TRANSFORMABLE SPACE STRUCTURE
Authors: ZIMIN V.N. , KRYLOV A.V. , KUVYRKIN G.N. , SHAKHVERDOV A.O.
Published: January 2022

Large-sized space structures are delivered into space orbits in a folded, tightly packed form allowing transformation of the structure from the transport position to the unfolded operating state. Deployment of the transformable structure is fulfilled by force drives which are usually various types of springs or electric motors. Designing such space structures, it is necessary to take into account dynamic impact loads that arise during the transformation. To avoid dynamic loads on the deploying structure elements, it is proposed to use actuators made of material with a shape memory effect. An active element made of titanium nickelide wire, which is heated during operation by the electric current passing through it, is used in the actuator. Experimental studies of the actuator active elements have proved that such actuators can be used for deployment of the transformable space structures.
REGISTRATION OF GEODYNAMIC PROCESSES BY THE PHASOMETRIC METHOD IN LOCAL GEOECOLOGICAL MONITORING SYSTEMS
Authors: SURZHIK D.I. , KUZICHKIN O.R. , VASILIEV G.S. , BAKNIN M.D. , PANKINA E.S.
Published: January 2022

The article discusses the principles of processing recorded signals in local geoecological monitoring systems for the formation of phase images of geodynamic processes. The importance of continuous monitoring and control over the influence of geodynamic processes on natural resources and infrastructure engineering and technical objects in the process of their interaction is noted. It is shown that an effective option for local geoecological monitoring of these processes is the use of modern systems based on the use of geoelectric control methods, which are highly sensitive to changes in the electrical properties of the monitored objects. Along with the advantages of these methods, their disadvantages in controlling the amplitudes were noted, in particular, the complexity of solving monitoring problems in the presence of regular interference influences, changes in climatic factors and variations in the parameters of a specific measuring installation, in connection with which it is shown that the application of the method based on phase control is promising. higher sensitivity and noise immunity. A mathematical description of the phase–measuring method is given, structural diagrams and functional models are developed, which can be used for the practical implementation of measuring paths of systems for local geoecological monitoring of various geodynamic processes. The proposed approach was successfully experimentally tested in the process of studying a model of a phase–measuring measuring system for monitoring geodynamic karst processes in the coastal zone of Lake Svyato, Nizhny Novgorod region, which showed its high sensitivity to recording changes in phase images for extremely small geodynamic processes of natural and artificial origin.
ALGORITHM FOR MODELING THE SPECTRAL TRANSPARENCY COEFFICIENT OF THE ATMOSPHERE IN THE INFRARED WAVELENGTH RANGE IN AERO OBSERVATION OF GROUND OBJECTS BASED ON INTERPOLATION OF EMPIRICAL DATA
Authors: GUSENITSA Ya.N. , SHIRYAMOV O.A. , BURYJ D.S.
Published: January 2022

The article presents an algorithm for modeling the spectral transparency of the atmosphere in the infrared wavelength range for aerial observation of ground objects based on the interpolation of empirical data. The proposed algorithm differs from the existing ones in that it combines analytical expressions and empirical data that can be used to interpolate the value of the absorption coefficient of infrared radiation by water vapor and carbon dioxide. The paper presents theoretical calculations of the absorption and scattering of infrared radiation by the atmosphere, on which the proposed algorithm is based. The results of testing the algorithm in the course of flight experimental work are presented.
DETECTION OF FATIGUE CRACKS EARLY STAGE IN ROTATING MACHINE PARTS
Authors: NEMENKO A.V. , NIKITIN M.M.
Published: January 2022

A method for early diagnosis of fatigue based on the peculiarities of the stress field emerging on the surface of the part is proposed. The method is based on the representation of the stress field in the form of a complex–valued function of coordinates and the calculation of the integral from it along the outer contour of the section of the part, on which these stresses can be physically measured using sensors. If there are no cracks in the section, this integral is equal to zero, if there is a crack inside the contour containing both its ends, the integral abruptly takes on a non–zero value regardless of the actual size of the crack.
RESULTS OF THE STUDY OF THE INFLUENCE OF OXIDATION PROCESSES ON THE VISCOSITY–TEMPERATURE CHARACTERISTICS OF PARTIALLY SYNTHETIC MOTOR OILS
Authors: EFREMOVA E.A. , KOVALSKY B.I. , BEZBORODOV YU.N. , OLEINIK V.Z.
Published: January 2022

Engine oil is an important element in the design of an internal combustion engine and can provide a given resource only if its properties correspond to the thermal, mechanical and chemical influences to which it is subjected in the lubrication system and on the surfaces of parts heated to high temperatures and in the friction zone. Based on the analysis of control methods and processes occurring in engine oils, the main indicators that characterize their quality are thermal–oxidative stability, temperature resistance, lubricating properties and viscosity, which determine the resource of the engine oil. However, these indicators are mainly used in the control of oil production and are not widely used in the operation of various equipment. In addition, the influence of oxidation products on the kinematic viscosity, viscosity index, anti–wear properties and service life of lubricating oils, and most importantly, the mechanism of formation of temperature control products, their structure and energy consumption, are not sufficiently studied. therefore, the purpose of these studies is to determine the potential service life of motor oils, as well as the influence of oxidative processes on the viscosity–temperature characteristics of motor oils and to justify the criteria for their evaluation. This paper presents the results of a study of the effect of oxidative processes on the viscosity–temperature characteristics of partially synthetic motor oils: Castrol Magnatec 10W–40 and Rosneft Maximum 10W–40 SL/CF. at temperature control temperatures of 180.170 and 160°C. The potential resource and the criterion of the viscosity–temperature characteristic determined by the product of the optical density and the viscosity index are proposed as an indicator for justifying the maximum permissible temperature of the working capacity of motor oils.
VARIABLE CLEARANCE SLIDING BEARING: SIMULATION OF A CONTROL SYSTEM
Authors: KORNAEV A.V. , SAVIN L.A. , KAZAKOV Yu.N.
Published: January 2022

The article discusses the development of a simulation model for a tapered bearing of fluid friction. The work includes the main stages of modeling a liquid film in a bearing assembly, modeling the dynamics of a rotor. A method for solid modeling of objects in the Simulink environment is presented. The results of the approximation of the solution of the Reynolds equation by artificial neural networks are presented. As the simulation results, the graphs of the rotor movement as well as the relationship between the friction torque and the axial displacement of the shaft are presented.
SYSTEM FOR SIMULATING THE OPERATION OF AN AUTOMATED WAREHOUSE IN DISCRETE PRODUCTION
Authors: CHENGAR O.V. , SHEVCHENKO V.I. , MALITSKAYA A.A. , SHEVCHENKO D.D.
Published: January 2022

The article discusses the functions of the warehouse subsystem of industrial production of a discrete type, describes the graph and simulation models of the functioning of an automated warehouse of a small–scale machine–building enterprise. The structure of the software implementation of the subsystem is proposed. As a result of a computer experiment, the adequacy of the presented models was verified. Variants of possible experimental studies of the modeling system to improve the efficiency of discrete production processes are proposed.
RESEARCH OF LIQUID BREATHING TECHNOLOGY FOR REMOVING NITROGEN FROM THE BIO–OBJECT BY MEASURING INFORMATION SYSTEM
Authors: POLIVTSEV V.P. , KRUGOVOY A.N. , KALININ M.I. , POLIVTSEV V.V.
Published: January 2022

Investigations of the technology of liquid respiration for the process of removing nitrogen from the body of biological objects before decompression are proposed. Safe decompression modes are being explored. A gas–liquid artificial lung ventilation apparatus has been developed and tested. The main characteristics of a pressure chamber are given, which provides respiration of a biological object under excessive increased air pressure and a rapid release of pressure to atmospheric pressure. The results of medical research of a biological object on such basic parameters as ECG, ultrasound, X–ray and other instrumental research methods are presented.
CRITERION ESTIMATOR OF THE CRACK ABSENCE IN A LOADED ROTATING OBJECT
Authors: NEMENKO A.V. , NIKITIN M.M.
Published: January 2022

We propose a classifier of the absence of cracks in a rotating part based on the analysis of the stress field as a function of complex coordinates. A sufficient condition for the crack absence in the existence of some finite limit composed of the power series coefficients of the function connecting shear stresses during torsion with complex coordinates in the section to be studied. We show that within an appropriate choice of the control point on the cross–sectional contour, the application of the method makes it possible to use only one stress sensor placed on it.
GENERALIZATION OF THE PRINCIPLE OF MOTIONS COMBINATION ON CIRCULAR MOTIONS
Authors: PAVLOV V.D.
Published: January 2022

The aim of the research is to generalize the principle of a combination of movements to circular movements. The relevance of the work is due to the fact that combined rotational movements are widespread in technical systems, and when designing it is important to represent the nature of the total movement. It has been established that when rotating in opposite directions, the trajectory of the total motion is an ellipse. All the standard characteristics of the ellipse are determined in relation to the case under consideration. The inclination of the elliptical trajectory is set. Just as the result of the superposition of two unaccelerated movements is also unaccelerated, i.e. uniform and rectilinear movement, with rotations in one direction, the trajectory of the total movement is a circle. The practical aspect of the study is determined by the fact that the formulas obtained can be directly used in CAD when performing design work.
SIMULATION OF THE CALCULATION PROCESS USING DEFORM–3D AND SOLIDWORKS SYSTEMS
Authors: SELEMENEV M.F. , FROLENKOVA L.YU. , TARAPANOV A.S. , PETRUKHIN A.V. , TITOV D.I.
Published: January 2022

The article is devoted to the use of tool nanocoatings for countersinking. It is shown that epilation is a rapidly developing direction for increasing the efficiency of the cutting tool operation. To study the effect of nanofilms on the process of heat generation and to establish changes in contact stresses, a comparison was made between epilamated and non–epilated tools under different processing modes. It was found that the use of epilam coatings under the same processing conditions can significantly reduce the maximum cutting temperature.
ROTOR TRAJECTORIES ON MAGNETORHEOLOGICAL FLUID–FILM BEARINGS
Authors: FETISOV A.S. , KAZAKOV Yu.N. , TOKMAKOV N.V.
Published: January 2022

The article presents the results of a computational experiment to simulate the dynamics of a rotor on plain bearings lubricated with a magnetorheological fluid. The results of calculating the dynamic coefficients are presented. A description of a rigid rotor model on fluid friction supports is given. The results of modeling the dynamics of a rigid rotor on magnetorheological sliding bearings are presented. The summary data on the value of the maximum amplitude of vibration displacements of the rotor are given.