bluuebunny/crossref_metadata_2025 huggingface dataset:
Theoretical analysis on the VSC instability caused by PLL in weak system
Authors: Li Baohong , Chen Shi , Liu Tianqi
Published: April 2020

The mechanism of voltage sourced converter's (VSC) instability caused by phase‐locked‐loop (PLL) in weak system is revealed in a simplified and efficient way. Based on the key‐variables small signals model, the PLL's impact to VSC stability is described by the defined low frequency torque and high frequency torque. The low frequency torque decides the characteristic of VSC in low frequency domain, and supplies synchronous ability and low frequency damping to VSC, while the high frequency torque decides VSC's high frequency characteristic and supply high frequency damping. The two torques impact factors are researched and their influences are revealed. It is found that to keep system stable, sufficient torques are needed. Because weakening system strength will decrease both torques, the mechanism of the instability caused by PLL in weak system is actually lack of sufficient torques. The simulation based on PSCAD software is implemented to validate the theory and matches well with the proposed theory.
Flexible power‐point‐tracking‐based frequency regulation strategy for PV system
Authors: Zhong Cheng , Zhou Yang , Zhang Xiao‐Ping , Yan Gangui
Published: April 2020

This study proposes a novel frequency regulation strategy based on a power reserve control method. Unlike existing strategies, irradiance information and complex model estimation are not required, except for the maximum power curve. The suboptimal power point at any irradiance and reserve ratio can be automatically converged with the proposed tracking method. Furthermore, an adaptive step‐size tracking method is proposed to improve the output power fluctuation around the suboptimal power point. The simulation results with several scenarios are used to verify that the proposed strategy can quickly and robustly track a given power reserve ratio under the irradiance and reserve ratio variation conditions. The proposed strategy can significantly improve the frequency response of power systems with photovoltaic (PV) generation.
Accretion and jets in a low-luminosity AGN: the nucleus of NGC 1052
Authors: Falocco S. , Larsson J. , Nandi S.
Published: April 2020

Aims. We aim to determine the properties of the central region of NGC 1052 using X-ray and radio data. NGC 1052 (z = 0.005) has been investigated for decades in different energy bands and shows radio lobes and a low-luminosity active galactic nucleus.

Methods. We used X-ray images from Chandra and radio images from Very Large Array to explore the morphology of the central area. We also studied the spectra of the nucleus and the surrounding region using observations from Chandra and XMM-Newton.

Results. We find diffuse soft X-ray radiation and hot-spots along the radio lobes. The spectrum of the circum-nuclear region is well described by a thermal plasma (T ∼ 0.6 keV) and a power law with photon index Γ ∼ 2.3. The nucleus shows a hard power law (Γ ∼ 1.4) modified by complex absorption. A narrow iron Kα line is also clearly detected in all observations, but there is no evidence for relativistic reflection.

Conclusions. The extended emission is consistent with originating from extended jets and from jet-triggered shocks in the surrounding medium. The hard power-law emission from the nucleus and the lack of relativistic reflection supports the scenario of inefficient accretion in an advection-dominated accretion flow.
Wind accretion in Cygnus X-1
Authors: Meyer-Hofmeister E. , Liu B. F. , Qiao E. , Taam R. E.
Published: April 2020

Context. Cygnus X-1 is a black hole X-ray binary system in which the black hole captures and accretes gas from the strong stellar wind emitted by its supergiant O9.7 companion star. The irradiation of the supergiant star essentially determines the flow properties of the stellar wind and the X-ray luminosity from the system. The results of three-dimensional hydrodynamical simulations of wind-fed X-ray binary systems reported in recent work reveal that the ionizing feedback of the X-ray irradiation leads to the existence of two stable states with either a soft or a hard spectrum.

Aims. We discuss the observed radiation of Cygnus X-1 in the soft and hard state in the context of mass flow in the corona and disk, as predicted by the recent application of a condensation model.

Methods. The rates of gas condensation from the corona to the disk for Cygnus X-1 are determined, and the spectra of the hard and soft radiation are computed. The theoretical results are compared with the MAXI observations of Cygnus X-1 from 2009 to 2018. In particular, we evaluate the hardness-intensity diagrams (HIDs) for its ten episodes of soft and hard states which show that Cygnus X-1 is distinct in its spectral changes as compared to those found in the HIDs of low-mass X-ray binaries.

Results. The theoretically derived values of photon counts and hardness are in approximate agreement with the observed data in the HID. However, the scatter in the diagram is not reproduced. Improved agreement could result from variations in the viscosity associated with clumping in the stellar wind and corresponding changes of the magnetic fields in the disk. The observed dipping events in the hard state may also contribute to the scatter and to a harder spectrum than predicted by the model.
Searching for the near-infrared counterpart of Proxima c using multi-epoch high-contrast SPHERE data at VLT
Authors: Gratton R. , Zurlo A. , Le Coroller H. , Damasso M. , Del Sordo F. , Langlois M. , Mesa D. , Milli J. , Chauvin G. , Desidera S. , Hagelberg J. , Lagadec E. , Vigan A. , Boccaletti A. , Bonnefoy M. , Brandner W. , Brown S. , Cantalloube F. , Delorme P. , D’Orazi V. , Feldt M. , Galicher R. , Henning T. , Janson M. , Kervella P. , Lagrange A.-M. , Lazzoni C. , Ligi R. , Maire A.-L. , Ménard F. , Meyer M. , Mugnier L. , Potier A. , Rickman E. L. , Rodet L. , Romero C. , Schmidt T. , Sissa E. , Sozzetti A. , Szulágyi J. , Wahhaj Z. , Antichi J. , Fusco T. , Stadler E. , Suarez M. , Wildi F.
Published: April 2020

Context. Proxima Centauri is the closest star to the Sun and it is known to host an Earth-like planet in its habitable zone; very recently a second candidate planet was proposed based on radial velocities. At quadrature, the expected projected separation of this new candidate is larger than 1 arcsec, making it a potentially interesting target for direct imaging.

Aims. While identification of the optical counterpart of this planet is expected to be very difficult, successful identification would allow for a detailed characterization of the closest planetary system.

Methods. We searched for a counterpart in SPHERE images acquired over four years through the SHINE survey. In order to account for the expected large orbital motion of the planet, we used a method that assumes the circular orbit obtained from radial velocities and exploits the sequence of observations acquired close to quadrature in the orbit. We checked this with a more general approach that considers Keplerian motion, called K-stacker.

Results. We did not obtain a clear detection. The best candidate has signal-to-noise ratio (S∕N) = 6.1 in the combined image. A statistical test suggests that the probability that this detection is due to random fluctuation of noise is <1%, but this result depends on the assumption that the distribution of noise is uniform over the image, a fact that is likely not true. The position of this candidate and the orientation of its orbital plane fit well with observations in the ALMA 12 m array image. However, the astrometric signal expected from the orbit of the candidate we detected is 3σ away from the astrometric motion of Proxima as measured from early Gaia data. This, together with the unexpectedly high flux associated with our direct imaging detection, means we cannot confirm that our candidate is indeed Proxima c.

Conclusions. On the other hand, if confirmed, this would be the first observation in imaging of a planet discovered from radial velocities and the second planet (after Fomalhaut b) of reflecting circumplanetary material. Further confirmation observations should be done as soon as possible.
Connection of supernovae 2002ap, 2003gd, 2013ej, and 2019krl in M 74 with atomic gas accretion and spiral structure
Authors: Michałowski Michał J. , Gotkiewicz Natalia , Hjorth Jens , Kamphuis Peter
Published: April 2020

Studying the nature of various types of supernovae (SNe) is important for our understanding of stellar evolution. Observations of atomic and molecular gas in the host galaxies of gamma-ray bursts (GRBs) and SNe have recently been used to learn about the nature of the explosions themselves and the star formation events during which their progenitors were born. Based on archival data for M 74, which previously has not been investigated in the context of SN positions, we report the gas properties in the environment of the broad-lined type Ic (Ic-BL) SN 2002ap and the type II SNe 2003gd, 2013ej, and 2019krl. The SN 2002ap is located at the end of an off-centre, asymmetric, 55 kpc-long HIextension containing 7.5% of the total atomic gas in M 74, interpreted as a signature of external gas accretion. It is the fourth known case of an explosion of a presumably massive star located close to a concentration of atomic gas (after GRBs 980425, 060505, and SN 2009bb). It is unlikely that all these associations are random (at a 3σsignificance), so the case of SN 2002ap adds to the evidence that the birth of the progenitors of type Ic-BL SNe and GRBs is connected with the accretion of atomic gas from the intergalactic medium. The HIextension could come from tidally disrupted companions of M 74, or be a remnant of a galaxy or a gas cloud that accreted entirely from the intragroup medium. The other (type II) SNe in M 74 are located at the outside edge of a spiral arm. This suggests that either their progenitors were born when gas was piling up there or that the SN progenitors moved away from the arm due to their orbital motions. These type II SNe do not seem to be related to gas accretion.
First observations and magnitude measurement of Starlink’s Darksat
Authors: Tregloan-Reed J. , Otarola A. , Ortiz E. , Molina V. , Anais J. , González R. , Colque J. P. , Unda-Sanzana E.
Published: April 2020

Aims. We measured the Sloan g′ magnitudes of the Starlink’s STARLINK-1130 (Darksat) and 1113 low Earth orbit (LEO) communication satellites to determine the effectiveness of the Darksat darkening treatment at 475.4 nm.

Methods. Two observations of the Starlink’s Darksat LEO communication satellite were conducted on 2020/02/08 and 2020/03/06 using Sloan r′ and g′ filters, respectively. A second satellite, STARLINK-1113, was observed on 2020/03/06 using a Sloan g′ filter. The initial observation on 2020/02/08 was a test observation conducted when Darksat was still in the process of manoeuvring to its nominal orbit and orientation. Based on the successful test observation, the first main observation took place on 2020/03/06, along with an observation of the second Starlink satellite.

Results. The calibration, image processing, and analysis of the Darksat Sloan g′ image gives an estimated Sloan g′ magnitude of 7.46 ± 0.04 at a range of 976.50 km. For STARLINK-1113, an estimated Sloan g′ magnitude of 6.59 ± 0.05 at a range of 941.62 km was found. When scaled to a range of 550 km and corrected for the solar and observer phase angles, a reduction by a factor of two is seen in the reflected solar flux between Darksat and STARLINK-1113.

Conclusions. The data and results presented in this work demonstrate that the special darkening coating used by Starlink for Darksat has darkened the Sloan g’ magnitude by 0.77 ± 0.05 mag when the range is equal to a nominal orbital height (550 km). This result will serve members of the astronomical community who are actively modelling the satellite mega-constellations to ascertain their actual impact on both amateur and professional astronomical observations. Both concurrent and subsequent observations are planned to cover the full optical and NIR spectrum using an ensemble of instruments, telescopes, and observatories.
Our sustainable coronavirus future
Authors: Semerikov Serhiy , Chukharev Serhii , Sakhno Serhiy , Striuk Andrii , Osadchyi Viacheslav , Solovieva Victoria , Vakaliuk Tetiana , Nechypurenko Pavlo , Bondarenko Olga , Danylchuk Hanna
Published: April 2020

This is an introductory text to a collection of papers from the ICSF 2020: The International Conference on Sustainable Futures: Environmental, Technological, Social, and Economic Matters, which held at Kryvyi Rih National University, Kryvyi Rih, Ukraine, on May 20-22, 2020. It consists of an introduction, conference topics review, and some observations about the event and its future.
Methodology for calculating the number of migratory birds in the territory of the wind farms of the Azov region using information and communication technology
Authors: Yeremieiev Volodymyr , Osadchyi Viacheslav , Siokhin Valerii , Gorlov Petro
Published: April 2020

A methodology has been developed for calculating the number of migratory birds in the territory of wind power farms and the StatBirds1 program for statistical analysis of bird monitoring results at the wind power farm “Prymorsk-1” on the coast of the Sea of Azov in the Zaporizhzhya Region. In the process of accounting, the type and number of birds, the direction and type of flight (transit, feeding, demonstration), the height and length of the flight, the time each bird was in the observation areas were recorded. Monitoring was carried out during 24 days in 2017 at three observation areas in the territory of the wind farm.
Monitoring of trace element content in tap water from Karachuny Reservoir, Kryvyi Rih city
Authors: Stoliarenko Viktoriia , Chernova Marina , Yakovchuk Olga
Published: April 2020

Control of the trace element content in tap water is particularly important for large industrial regions. The estimation of Cd, Pb, Cu, As, Ni, Zn, Mn, Hg, Se and Co concentration in the tap water of Kryvyi Rih city (Karachuny Reservoir) was accomplished using electrochemical methods, the most popular methods for determining the content of trace elements in natural objects and tap water. A simple and rapid method to determine trace elements in the tap water (Kryvyi Rih city) by inversion-voltammetry has been used. The concentration of trace elements was measured by voltammetricanalyzer AVA-2 device that implements the method of inversion voltammetry on a solid rotating electrode made of carbon material. The monitoring of the trace element content in the water of the Karachuny reservoir was carried out on a monthly basis between September 2018 and August 2019. The article presents the obtained voltamperograms of some trace elements, describes content of the trace element in tap water during the year (12 data for each trace element) and analyzes the compliance of drinking water in the city of Kryvyi Rih to the standards and normative indicators of drinking water quality.
Visual test determination of trace amounts of germanium in the form of an ionic associate of 12-molybdogermanate with astrafloxin
Authors: Selivanova Tetiana , Vishnikin Andrey , Tsiganok Lyudmila
Published: April 2020

Sorption-colorimetric and naked eye determination of germanium as ion associates of GeMo O 4– with triphenylmethane dyes is described. The sorption of the ionic associates (IA) of 12molybdogermanat with astrafloxin (AF) on filter paper was studied. The colored scales for naked eye detection and dependence of chromaticity coordinates from the germanium (IV) concentration were obtained. The methods were applied to the determination of germanium (IV) in coked coal, iron ore, and in waters in the concentration range from 4•10–8 to 1•10–6 mol•L–1. The developed test-systems for the determination of Germanium in natural and technological objects were tested in the course of training students of chemistry of Kryvyi Rih State Pedagogical University.
The use of new structural solutions of retaining walls to ensure the stable operation of the “base – engineering structure” system
Authors: Timchenko Radomir , Popov Stanislav , Nastich Oleg , Krishko Dmitry , Savenko Vladimir
Published: April 2020

During the design and operation practice, it is necessary to assess the possibility of deformation of structures located on foundations which are able to precipitate and subside. Only with reliable and accurate determination of the stress-strain state of structures of structures together with soil masses during modeling, it is possible to apply the finite element method in practice. The calculations using the PLAXIS and LIRA programs made it easier to analyze the stress-strain state of the soil mass and the stability of retaining walls: I option is corner retaining wall; II option is retaining wall with a structural surface. With the same soil base (layer geometry and physicomechanical properties), loads and boundary load conditions, it is obvious that for the II option the entire mass of soil is included in the work and the stresses are uniformly distributed over the front and foundation plates (over common stresses), uniform structural deformations are observed and soil base, which, in turn, ensures the stability of the retaining wall (according to the general picture of movements) The validity of the theoretical forecast of the behavior of engineering structures interacting with an unevenly deformed base cannot be obtained on the basis of the regulatory framework. This gap can be filled in when modeling the “base – engineering structure” system using modern calculation programs using the finite element method.
Study of rock structure properties during combined stopping and development headings
Authors: Golik Vladimir , Stas Galina , Morkun Vladimir , Morkun Natalia , Gaponenko Irina
Published: April 2020

The purpose of this study is to establish the mechanism of interaction between stresses and strains and their quantitative values at the intersection of stopping and development headings to optimize methods for controlling the behaviour of the rock massif. The research complex includes priority methods with experimental confirmation of the calculated parameters by geophysical studies, including stress calculation by a sensor system and surveying levelling to measure deformations using support frames. The properties of the massif and the role of faults and macro-cracks in the development of a field of a complex structure are systematized. A method for studying the stresses and deformations of rocks at the intersection of stopping and development headings is given. The patterns of the rock massif behaviour at the point of intersection are established. The article provides quantitative values of changes in the physical and mechanical properties and stability of rocks at the point of intersection. Massif was differentiated according to the magnitude of the effective stresses in different phases of the intersection. Stresses for specific conditions were calculated with the determination of the reliability of the mining site. The patterns of change in stresses and strains in time are noted.
The study of the lining layer abrasing wear in the semi-autogenous grinding mill
Authors: Sokur Mykola , Biletskyi Volodymyr , Fyk Mykhailo , Fyk Oleksandr , Zaselskiy Igor
Published: April 2020

In this work complex investigations of the abrasing wear of lining of self-grinding mills (semiautogenous grinding mills) are carried out with the obtaining of mathematical models of wear-abrasing of elevators in terms of height, weight, volume and worn-out area. In particular, according to the location and nature of the abrasing wear processes, the liner-lifters mill self-grinding are identified in three typical groups. During 1 year, in the conditions of Ingulets GOK, the monitoring of the abrasing wear of selected groups of lifters of self-grinding mills was performed. On the basis of the experimental data calculationed in the Microsoft Office Excel program, a set of mathematical models of lifter abrasing wear was obtained in terms of height, weight, volume and worn-out area. The obtained dependencies are recommended for prediction of abrasing wear of lining and necessary frequency of replacement of inserts-lifters. In addition, the research of wear of lining made of cast iron RF–4, showed a significant reduction in their abrasing wear compared with steel 110G13L. Thus, it has been shown that the selection of liner-lifters materials can reduce the inter–repair period by 3 times or more (replacement of worn-out lifters). A comparison of the actual picture of the abrasing wear of elevators and Simulation Statics simulated result (using SolidWorks) stresses shows the convergence of the arrangement of the zones of maximum stresses and the maximum abrasing wear of the lining. Investigation of the influence of the stressed state of lining plates on the intensity of their abrasing wear – a promising direction for further research.
Development of intelligent energy systems: the concept of smart grids in Uzbekistan
Authors: Khushiev Sirojiddin , Ishnazarov Oybek , Tursunov Obid , Khaliknazarov Urolboy , Safarov Bekhzod
Published: April 2020

In the process of energy reform, liberalization and deregulation of the electricity market, a number of features have been identified that are related to the fact that in the conditions of market relations, the economic benefit and the price of electricity for consumers become a priority. There is certain isolation of networks and power lines from generation facilities; attention is lost to such an important problem as the reliability and safety of power supply. In this situation, the load on the power elements of the electric network increases, there is a need to create appropriate reserves of generating capacities, to increase the throughput of electric networks. All this involves increasing the role of system operators and improving supervisory control systems. The strategic goal of this study was to analyze the development of the electric power complex by the creation of smart grid systems as a platform for market, managerial and technological innovations that provide a transition to a new level of development of the electric power industry in Uzbekistan.
PhotosynQ – cloud platform powered by IoT devices
Authors: Herts Andriy , Tsidylo Ivan , Herts Nataliia , Barna Ljubov , Mazur Stanislav-Ivan
Published: April 2020

This article describes how to connect to PhotosynQ and some of the features of a cloud service. The focus is on organizing communication between the web service and the Internet of Things. An example and procedure for integrating a number of digital encoders that are not included in the list supported by the default platform through modification of the open-source base firmware is given. It has been suggested that in the future, a number of tools can be designed in the future, including for environmental monitoring, using basic digital sensors included in the so-called Arduino UNO Kit kits and more. It is emphasized that the PhotosynQ web platform, which is related to the SaaS cloud computing model, is an environment for collecting, analyzing, deriving and discussing results where research protocols and calculation procedures are open access. Its primary focus is only on working with a specific list of dashboards, offset by the openness of the software itself, which provides communication with the platform.
Information and measurement system of weapon stabilization parameters based on precision piezoelectric sensitive element
Authors: Tkachuk Andrii , Bezvesilna Olena , Dobrzhanskyi Oleksandr , Ostapchuk Anna , Horodyskyi Mykola
Published: April 2020

The structure and principle of information and measurement system performance of weapon stabilization are described. Established, that the classical stabilization system consists of a stabilizing platform of the sensitive element (or block of sensitive elements), defining the absolute angle of platform α rotation, the sensing element output signal amplifier, engines and tachometers. The classical system of indirect stabilization is reviewed, its mathematical description is made. A new precision sensitive element for the information and measurement system of weapon stabilization is suggested, the principle of its performance is introduced. Constructive methods of measurement accuracy improvement in the new sensitive element are analyzed. A simulation of the new sensitive element performance influenced by the external disturbances is carried out.
Diagnostics and regulation of rheological characteristics for injection mortars by electromechanical sensors
Authors: Plugin Andrii , Trykoz Liudmyla , Donets Oleksandr , Nykytynskyj Andrii , Pluhin Anton
Published: April 2020

In the article the diagnostic and regulation problems are considered for the rheological characteristics of mortars which are used for pumping into the interpipe gaps or cracks during repairing the pipelines, tunnels, and other objects. It is important to obtain the necessary mortar viscosity which allows providing a complete hole filling. For this aim the experimental dependencies have been determined between the injection mortar viscosity, the water-cement ratio, and the additives quantity in the mortars. According to the Poiseuille’s flow law the theoretical dependencies have been obtained between the penetration depth of the injection mortar and viscosity under the different water-cement ratios. The said dependencies are a base during the development of the functioning algorithm the diagnostic and regulation system of the injection cement mortars rheological characteristics. The description of this functioning system is given. The mentioned system application allows increasing the cementation quality, corrosion resistance and durability of the repaired pipeline sections as well as decreasing of the work duration and labor costs.
Sustainable low-carbon binders and concretes
Authors: Sanytsky Myroslav , Kropyvnytska Tetiana , Fic Stanislav , Ivashchyshyn Hanna
Published: April 2020

Sustainable development depends on a consistency of interests, social, ecological and economic, and that the interests are evaluated in a balanced manner. In order to reduce CO2 emissions, the conception of decreasing clinker factor and increasing the role of supplementary cementitious materials (SCMs) in the cementitious materials has high economical and environmental efficiency. The performance of clinkerefficient blended cements with supplementary cementitious materials were examined. The influence of superfine zeolite with increased surface energy on the physical and chemical properties of low-carbon blended cements is shown. Increasing the dispersion of cementitious materials contributes to the growth of their strength activity index due to compaction of cement matrix and pozzolanic reactions in unclincker part. In consequence of the early structure formation and the directed formation of the microstructure of the cement matrix is solving the problem of obtaining clinker-efficient concretes. Shown that low-carbon blended cements with high volume of SCMs are suitable, in principle, for producing structural concretes.
Researching of physicochemical and structural-phase transformations in carbothermal titanomagnetite concentrates reduction for sustainable development of raw materials base of metallurgical enterprises
Authors: Baboshko Dmytro , Saithareiev Levan , Hubin Hennadiy , Vodennikova Oksana , Skidin Ihor
Published: April 2020

This study displays results of carbothermal reduction researches of titanоmagnetite concentrate obtained during complex apatite-titanomagnetite-ilmenite ore dressing. The mineral composition was analyzed and the structural and textural features of the titaniferous ore of Kropivensky deposit and the titanomagnetite concentrate obtained from it were revealed. The mechanism of solid-phase carbothermal the titanomagnetite concentrate reduction is investigated. Temperature-time parameters have been discovered to ensure the formation of both products with the maximum yields of iron and titania from metal and slag-phase during titanomagnetite concentrate reduction. One-stage resource-saving flow chart of titanomagnetite concentrate processing with mass fraction up to 25% TiO2 is developed.. It allows to obtain two marketable products: granular cast iron (92-96.5% Fe, 3.4-3.7% C, 0.5% V) in 57% yield and titaniferous slag (50-55% TiO2, up to 7.4% FeO) in 43% yield.
Formation of flash-concept for a resource-saving articulated hopper car to transport hot pellets and agglomerate
Authors: Fomin Oleksij , Vatulia Glib , Lovska Alyona
Published: April 2020

Higher operational efficiency of hopper cars can be achieved with the flash-concept for a resourcesaving structure. The characteristic feature such cars is the use of circular pipes as the carrying body elements. The engineering solution made it possible to decrease the tare weight of a hopper car in comparison with that of a prototype by 5%. A 20-9749 hopper car, manufactured by Panutinskiy Car Repair Plant (Ukraine), was taken as a prototype. On the basis of the suggested hopper car, an articulated car was designed. The dynamic loading of the articulated hopper car was defined with mathematical modelling. The study was conducted in plane coordinates. The acceleration values obtained were considered in the strength calculation for the carrying structure of the hopper car. The strength factors were defined in COSMOSWorks software environment. It was determined that the maximum equivalent stresses in elements of the carrying structure did not exceed the admissible values. The results of the research will promote designing innovative hopper cars for transporting hot pellets and agglomerate, thus enhancing higher efficiency of rail transportation.
Determination of forces in the elements of the brake rigging of bogies of freight cars
Authors: Elyazov İsrail , Ravlyuk Vasyl , Rybin Andriy , Hrebeniuk Vitalii
Published: April 2020

The article presents the results of studies the purpose of which was solving the problem of deceleration of abnormal wear of brake pads in freight cars of Ukrzaliznytsia JSC. In the studies, the design schemes of brake rigging during braking were considered theoretically. Particular attention was paid to the determination of force loads acting in the rods of the rigging and the contact area of the brake pads with the rolling surfaces of the wheels during braking. Design analysis was performed to determine rational solutions from the point of view of determined force load of the rigging elements of the bogies during braking, in particular, taking into account the action of harmful torque caused by the movement of the bogie on inequalities “track joints”. Based on the conducted studies, it was decided to create a 2D generalized model diagram to determine reliable information on the operation of triangle brake rigging.
Calculation of tube concrete elements with strengthened cores by numerical method
Authors: Palyvoda Oleksandr , Yermolenko Dmytro , Demchenko Oksana , Andriichuk Oleksandr , Nyzhnyk Oleksandr
Published: April 2020

The paper considers the features of formation of finite element models of tube confined concrete structural elements in the form of centrally compressed rod with strengthened cores. The prerequisites, which underlies the proposed approach to the formation of finite element models of tube confined concrete elements with strengthened cores, are given. Lengthwise the tube confined concrete elements have constant dimensions and a set of cross-sectional components. It is proved that the use of high-strength concrete allows performing calculations in the elastic stage of the work of materials. When modeling the work of rod reinforcement in tube confined concrete elements with strengthened cores, it can be represented as an imaginary cylinder with a cross-sectional area equal to the area of the rod reinforcement. The proposed prerequisites for the numerical simulation of the work of tube confined concrete elements with the strengthened cores of the studied types allowed to construct adequate finite element models. The difference in the value of the load-bearing capacity obtained from the results of physical and numerical experimental studies was 5,94…7,72 %.
Blended learning for sustainable education: Moodle-based English for Specific Purposes teaching at Kryvyi Rih National University
Authors: Holiver Nadiya , Kurbatova Tetiana , Bondar Iryna
Published: April 2020

The article deals with the experience of implementing Information Communication Technologies (ICT) into ESP (English for Specific Purposes) teaching and learning. Informatization and application of innovations in education has resulted in emergence of e-learning. While Moodle is one of the most popular Learning Management Systems (LMS) and it enables and facilitates the shift to the student-centered education, the article highlights its implementation and adjustment to the specific nature of teaching and learning languages for specific purposes at Kryvyi Rih National University. The article touches upon reasons for applying Moodle to language teaching/learning and its advantages as a complement to the traditional face-to-face, or classroom, mode, thus combining them into what is referred to as blended learning, or b-learning. Both the teachers and learners interviewed demonstrated positive attitudes to using the platform in their practices. Besides, the article touches upon Moodle-based opportunities of managing the content and monitoring students’ activities both in general and by individual courses. As Moodle is a web-based distance education platform not initially developed for language learning, the article invites discussion on advantages and disadvantages of its application to teaching/learning foreign languages and finding out which factors may allow language teachers and learners to boost its use and reach the set goals.
The use of digital learning tools in the teachers’ professional activities to ensure sustainable development and democratization of education in European countries
Authors: Ovcharuk Oksana , Ivaniuk Iryna , Soroko Nataliia , Gritsenchuk Olena , Kravchyna Oksana
Published: April 2020

The article deals with the revealing and analysis of the experience of the teachers’ use of the digital tools in their professional activities in the European countries (Germany, Italy, Netherland, Denmark, Estonia, Croatia, Sweden, Finland, Macedonia, Norway and others). The online recourses ensuring the creation of the sustainable environment for teachers and students including key competencies areas: entrepreneurship, citizenship, civic education and STEM are revealed in the article. The presented recourses allow to creative use of digital technologies, identify teachers’ and students’ needs and finding technological answers, solve technical problems, identifying gaps in digital competence. Using the analysed resources teachers become aware of the need to improve and update their digital competence; ability to support others in developing their digital competence; search for opportunities for self-development and awareness of digital evolution that is proclaimed by the UN ‘2030 Agenda for Sustainable Development’ adopted in 2015. The objective is to present the examples of the use of digital tools by European teachers, which are aimed at building the digital environment, developing the digital competence, and introducing innovations in the learning process. The critical use of presented experience in the comparative perspective can improve domestic teaching practice and teachers’ professional development.
Education individualization by means of artificial neural networks
Authors: Valko Nataliia , Osadchyi Viacheslav
Published: April 2020

This paper examines the issues related to the implementation of an educational process based on modern information technologies use. The main purpose of it is to achieve a significant level of individualization of the educational process, taking into account the individual characteristics and capabilities of each participant of the process. The implementation of the approach became possible at using elements of the theory of artificial neural networks in the educational process. Based on the network, it is possible to build a model of the educational process; it will significantly increase the control of the teacher on the educational process. Moreover, this network can adapt to a specific education task, the individual characteristics of the student and teacher. The mathematical model of the educational process using modern information technologies and neural networks is constructed. Their use is based on the developed criteria of successful execution of various stages of the educational process. Such criteria are designed for both the student and the teacher. The characteristic of participant’s activity of the educational process is considered in the work. A numerical interpretation of this concept is proposed.
Psycho-pedagogical training as a mean of forming the occupational stress resistance of future teachers
Authors: Meshko Halyna , Meshko Oleksandr , Drobyk Nadia , Mikheienko Oleksander
Published: April 2020

Peculiarities of psycho-pedagogical training, and its role in the preparation of the future teachers for the preservation and strengthening of occupational health, formation of their professional stress resistance, and harmonization of personality are revealed in the article. Activity of the training group was described, aimed at: formation of skills of productive interaction and constructive overcoming of professional difficulties, formation of strategies of protection against stress, teaching of methods and techniques of self-regulation, formation of sanogenic thinking. Dynamics of psychological indicators of the occupational health of future teachers, who took part in the work of psycho-pedagogical training, was checked. Quantitative and qualitative analysis of the results of diagnostics (research of responses, selfreports of participants of training about their state of health, change of way of life or thinking, ways of interaction with others) was carried out. The effectiveness of psychological and pedagogical training as a means of forming professional stress resistance of future teachers has been proved.
The peculiarities of using the computer complex HC-psychotests in the process of psychodiagnosis of the level of development of future specialists’ mental capacity
Authors: Varina Hanna , Shevchenko Svetlana
Published: April 2020

The IT revolution, which has embraced material production, social relations and the whole sphere of culture and education, is more and more contributing to solving the problem of automation of intellectual processes in science, technology and society, as well. This scientific article is devoted to the consideration of topical issues of introduction of the computer complex HC-psychotests in the process of psychological support of professional-personal development of the future specialist during the period of study in high school. The article also presents the analysis of the versatile possibilities of using the NSpsychotest in the paradigm of modern education. In this scientific article, the results of the screening study with the use of HC-psychotest in the process of psychodiagnosis of the level of development of mental capacity of future specialists are analyzed in detail. It is determined that the complex HC-psychotests allowed to give multilevel, multiparametric characteristics of the mental states of the respondents with the use of psychological, psychophysiological, physiological and social indicators. It has been proved that the introduction of computer psychodiagnostics has not only enriched the experimental base with appropriate methods that facilitate the implementation of various research strategies, but also combined empirical work into a single technological cycle.
The use of information and communication technologies in training ecology students
Authors: Barna Iryna , Hrytsak Lіudmyla , Henseruk Halyna
Published: April 2020

Increasing demand for experts capable of high-quality assessment of the impact of a particular planned activity on the environment involves a more effective use of information and communication technologies (ICT) in the educational process of training ecology students. The authors present a methodology for students to study the educational material of the “Environmental Impact Assessment” course by using ICT. The methodology and algorithm for using the Padlet interactive whiteboard, Mindomo mind maps, Easel infographics, Google Drive and Google Docs in lectures and practical lessons are described. Particular attention is paid to the preparation of a group project using ICT. Tested in the Ternopil Volodymyr Hnatiuk National Pedagogical University, the methodology allows to implement a number of tasks such as: promotion of intensification and effectiveness of teaching; acquisition of practical skills to quickly find the necessary information on various online resources for ecology students; simulation of the real procedure of environmental impact assessment in the classroom; development of the ability to professionally communicate with experts in other fields of knowledge or activity, etc. Examination of the results of using ICT to study the “Environmental Impact Assessment” course has shown a significant increase in informational literacy among ecology students and their individual professional growth.
Expert assessment systems to support decision-making for sustainable development of complex technological and socio-economic facilities
Authors: Lavrov Evgeniy , Paderno Pavel , Burkov Evgeniy , Volosiuk Aleksandr , Lung Vu Duc
Published: April 2020

In this paper, we investigate problems of decision making in management systems for the sustainable development of complex technological and socio-economic facilities. We show both the limitations of traditional expert systems and decision support systems, and the necessity of using expert evaluation technologies to find possible development strategies. Based on that we substantiate the need of creating a new class of systems, i.e. Automated eXpert Assessment Systems, and propose their organizational structure and design principles. We substantiate the level of automation of the work performed during the examinations and describe the composition of models and computer programs we recommend for creating effective automated expert assessment systems and corresponding technology. In the paper, we give examples of using the proposed method for various areas of human activity, in the management of urban infrastructure and e-learning at the universities, and show the effectiveness of the developed approach.
Modern processes of regional economic integration of Ukraine in the context of sustainable development
Authors: Babenko Vitalina , Perevozova Iryna , Kravchenko Maryna , Krutko Marharyta , Babenko Dariia
Published: April 2020

Ensuring economic sustainable development in difficult political and economic conditions is one of the priority tasks for Ukraine. It is forced to reorient the vector of foreign economic cooperation, in particular, the integration formations of the European Union. The aim of the article is to study the development of the processes of regional integration of Ukraine to ensure sustainable economic development, as well as determine the priority direction of its regional integration. The role of Ukraine in the processes of economic integration at the present stage of development is analyzed. Based on the analysis of the current state and development features of the EU and Ukraine, the prospects for the activation of its participation in integration processes, namely entry into the EU, are substantiated. By analysis, the domestic market of Ukraine, the general state of development and its place in the world market are investigated. As a result, the features and barriers of Ukraine’s European integration and ways to address them were identified, as well as an attempt was made to identify the main areas of cooperation and ways to improve economic relations between Ukraine and the EU.
Management of changes in the insurance industry in the conditions of climate crisis
Authors: Nagaichuk Nelia , Shabanova Olena , Tretiak Natalia , Marenych Anatoliy , Chepeliuk Hanna
Published: April 2020

The insurance industry is rather effective in overcoming consequences of natural disasters. Insurance companies play a key role in financing natural disasters consequences, at the same time they sustain record losses and are in difficult financial conditions. Taking into account the above said, the issues of management of insurers risks is up-today and is connected with climate change. In article the content of “climate risk” as risk is specified, the emergence of which is caused by human activity, which leads to pollution, resulting from industrial activity and other sources that greenhouse gases (carbon dioxide) which are capable to absorb a range of infrared radiation generate and, as a result, predetermine warming of the global atmosphere that brings to change of structure of the world atmosphere and adds natural climate instability during the certain periods of time. The most destructive dangers threatening to mankind owing to global warming are systematized. Types of risks and their sphere of manifestation in Ukraine are outlined. The directions of adaptation of the insurance industry to changes, caused by climatic crisis are defined. Due to results of the research, the theoretical generalization and author’s solutions of a scientific task are offered, which appear in the development of scientific and methodical approaches and justification of practical recommendations about modernization of activity of insurance companies and reinsurers in the conditions of risks, generated by global climate changes. Scientific novelty of the research: specifying the role of the insurance industry regarding the prevention of risks connected with global warming.
Geographic particulars of the world’s population food ration
Authors: Kholoshyn Ihor , Burman Liudmyla , Nazarenko Tetiana , Mantulenko Svitlana , Panteleeva Natalia
Published: April 2020

The research of a human food ration is caused by the great social significance in solving the problem of proper supply the population with food in the world countries. The food problem has a most evident geographic character. The world countries having at their disposal various agro-climatic conditions, demographic resources and population growth rates, socio-economic potential, specialization and labor productivity of agriculture production, are essentially distinguished by the food supply level of population and by structural characteristics of food ration. The formation particulars of the world countries population food ration were considered and characterized in the article. The key characteristics and factors of the world population’s food ration were analyzed there. The geographic differences of food ration, as well as the world countries typology by distinctive features of food consumption through their division into groups (nutrition types) according to the content and quantity of basic components in food ration were determined in it.