Showing papers by "Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan published in 2018"

Modelling of the Return Traction Current Harmonics Distribution in Rails for AC Electric Railway System

Abstract: The problem of determination of the traction current harmonics distribution in rails generated by several trains that operated in AC feeder zone is considered. The investigations were caused by necessity to ensure electromagnetic compatibility of the new types of rolling stock equipped with electronic static converters with track circuits that are used in train movement control systems for detection of their positions. The great diversity of rolling stock, power supply and return current systems, and train detection systems installed in European countries leads to consideration of the electromagnetic compatibility problem taking into account the specific railway systems used in the each country. Investigation of the electromagnetic compatibility between different railway subsystems requires the use of simulation programs that help to reveal most critical conditions for electromagnetic compatibility at an early stage and also makes it possible to estimate electromagnetic interference from rolling stock in rails under the worst-case conditions, realization of which in the operating systems will require a lot of time and cost. This work consider evolved model for distribution of the traction current harmonics in rails from several trains. To illustrate the application of the considered model, the distribution of the traction current harmonics in rails was computed for25 kV AC direct feeding network depending on distance from electrical supply substation, the rail-to-earth conductance, and the number of trains in the feeder zone. The results of modeling of the harmonics distribution are in satisfactory agreement with the experimental data.

About Electromagnetic Compatibility of Track Circuits with the Traction Supply System of Railway

Abstract: Track circuits are of fundamental importance for the safety in railway systems. Thus, they must be immune from electromagnetic interference (EMI). To this aim they must be accurately characterized. The paper deals with the determination of spectrum composition of traction current with the electric traction. A method of measuring the parameters of track circuits (time and amplitude parameters of code current, flowing in rail lines, an input impedance of a track circuit, characteristic impedance and propagation constant) is considered Automated method of measurement of parameters of track circuits and harmonics of return traction current was elaborated by the car-laboratory. The harmonics coinciding with the code frequency are inadmissible for the track circuits.

A method for optimization of time intervals between rolling cuts on sorting humps

Abstract: Sorting humps are the main technical means providing the breaking- and making-up of freight trains. Automation of sorting process by implementing microprocessor control systems is the main direction of increasing hump yard capacity, enhancement of safety in trains breaking-up, improvement of working conditions on hump yards. However, for wider introduction of such systems at the humps, it is necessary to reduce their cost. One of the main tasks of hump control systems is the determination of the optimal cars exit speeds from the retarders. Its solution is significantly complicated because of the uncertainty of cars rolling resistance coefficient, wind velocity and direction, retarder control errors. The paper is aimed at solving the problem of searching for such cars exit speeds from the retarders that provide the longest time intervals between them at the switches. Implementation of this method will make it possible to improve the quality of sorting process as a whole by improving the software of microprocessor control systems for automatic humping, rather than by increasing their technical facilities, which as a result will reduce the cost of their construction and operation. The research results, when solving the problem of searching for cars exit speeds from the retarders, allow us to move from searching for the maximum of a nonlinear non-smooth function of two variables to solution of an equation with one variable, which significantly accelerates and simplifies the solution to the problem.

About Electromagnetic Compatibility of Rail Circuits With the Traction Supply System of Railway

Abstract: The paper deals with the determination of spectrum composition of traction current at the a. c. and d. c. traction. The most dangerous interferences are 50, 75 and 100 Hz harmonics for normal work of rail circuits at the d. c. traction. The harmonics, coinciding with the code frequency (25 Hz), are inadmissible for the rail circuits of railway section at the a. c. traction. The station rail circuits are protected from interference well enough.

Philosophical and sociocultural dimensions of personality psychological security

Abstract: Purpose. The dynamics and pace of social and economic transformations that are characteristic of modern society, lead to an increase in tension and the destruction of habitual stereotypes – ideals, values, norms, patterns of behaviour that unite people. These moments encourage us to rethink the understanding of "security" essence, in particular, psychological, which emphasizes the urgency of its study in the philosophical and sociocultural coordinates. Theoretical basis of the research is based on the philosophical methodology of K. Jaspers, E. Fromm and the A. Maslow’s psychological approach to understanding of a person. Originality . Psychological security is considered at different levels: first and foremost, society is a characteristic of social security, that is an analysis of how today’s social technologies, social changes affect the quality of life of the country’s population; secondly, the social environment – the family, the immediate environment, reference groups, training teams; thirdly, a person is an experience of his own security-insecurity, when it is possible to talk about the manifestations of psychological violence, when certain behavioral acts contribute to the violation of the security of the other or to self-destruction. It is found out that the knowledge of psychological security is closely connected with the socio-historical conditions of being, with the level of development of material and spiritual culture, with the interests and values prevailing in society, which determines its ontological, epistemological and axiological features. The presented issue is considered in the correlation of psychological security with types of scientific rationality – classical, nonclassical and post-nonclassical approaches, within the framework of which various perspectives, aspects, forms and types of psychological security are studied. Conclusions. The concept of security requires a systematic description of its manifestations, types, levels, concepts: security as the absence of dangers (based on the principle of dichotomy, that is, a certain whole consisting of two opposite parts, in this case, the whole is human existence); security as a certain activity to ensure or to prevent any threats or dangers (activity approach); security as a conscious necessity, the value of the individual. The study systematizes various ideas about psychological security in accordance with the logic of scientific knowledge: in the mainstream of classical, non-classical and post-nonclassical approaches.

Smart Home and Artificial Intelligence as Environment for the Implementation of New Technologies

Abstract: The technologies of a smart home and artificial intelligence (AI) are now inextricably linked. The perception and consideration of these technologies as a single system will make it possible to significantly simplify the approach to their study, design and implementation. The introduction of AI in managing the infrastructure of a smart home is a process of irreversible close future at the level with personal assistants and autopilots. It is extremely important to standardize, create and follow the typical models of information gathering and device management in a smart home, which should lead in the future to create a data analysis model and decision making through the software implementation of a specialized AI. AI techniques such as multi-agent systems, neural networks, fuzzy logic will form the basis for the functioning of a smart home in the future. The problems of diversity of data and models and the absence of centralized popular team decisions in this area significantly slow down further development. A big problem is a low percentage of open source data and code in the smart home and the AI when the research results are mostly unpublished and difficult to reproduce and implement independently. The proposed ways of finding solutions to models and standards can significantly accelerate the development of specialized AIs to manage a smart home and create an environment for the emergence of native innovative solutions based on analysis of data from sensors collected by monitoring systems of smart home. Particular attention should be paid to the search for resource savings and the profit from surpluses that will push for the development of these technologies and the transition from a level of prospect to technology exchange and the acquisition of benefits.

Problems of Providing International Railway Transport

Abstract: Due to its geographic location and developed transport infrastructure, Ukraine has a significant potential in the development of cargo transportation, primarily in international traffic, in particular as a transistor country in the logistics chain of trade between Asia and Europe. The possibilities of railway transport for the organization of transportation between the countries of the European Union and Ukraine are not used to the full extent, since there is a number of technical reasons of the transport systems incompatibility between Ukraine and European countries. In the course of the research, methods of analysis and synthesis were used to study prospects of the European and domestic system of international railway transportations, the experience of creating, operating and optimizing these systems. To compare the above mentioned options, the authors developed a model for predicting and assessing the efficiency of railway transport from the border of one state to the border of the other one.

Research of Safety Indicators of Diesel Train Movement with Two-Stage Spring Suspension

Abstract: The problem of the interaction of rolling stock with the rail track has been analyzed in the present paper. It has been established that in the process of transport science development a number of methods for determining the causes of wheel pairs derailment are developed, which, in a varying degree, take into account the peculiarities of their interaction. The problem of choosing the most accurate method for estimating the causes of rolling stock derailment becomes more complicated because of the lack of sufficient experimental data that would allow us to verify the adequacy of the models. The indicators of stability of the wheel against derailment, which are used on the railways of Ukraine and Europe, have been examined. Their dependences on the speed of movement were derived. It has been established that the increase of the speed of motion leads to the increase of the interaction power of the rolling stock with the rail track, which may, under certain operational parameters, provoke its derailment. As a result of the calculations, it has been shown that the use of norms for car design and calculation used on Ukrainian railways can lead to an inadequate estimation of traffic safety parameters, since it does not take into account the unevenness of the railway track. It has been established that the requirements of BS EN 14363: 2005 European norms are stricter in comparison with the norms for calculation and evaluation of the bearing elements strength and dynamic qualities of motor-vehicle rolling stock used on Ukrainian railways. A comparison of the experimentally and theoretically calculated values of the stability margin coefficient against wheel derailment of the first wheel pair of the diesel train car was carried out.

Resource-saving technologies of railway transportation of grain freights for export

Abstract: The research objective is to increase the efficiency of export railway transportation of grain freights in Ukraine by the introduction of consignor routing, a concentration of loading of grain on junction elevators and the organization of the movement of grain routes according to the schedule. According to the researchers in USA and EU, one of the effective directions for decreasing the expenses in a logistic chain of grain delivery to ports is consignor routing of railway transportation. Consignor routing of transportations of grain freights provides a concentration of their loading at junctions. The choice of junctions is proposed to be carried out on the basis of methods of the cluster analysis. For formation of regions for a concentration of grain loading the theory of sets and multicriteria optimization are used. As a result, on the basis of the modified simplex method are chosen 24 regions of possible concentration of grain loading that cover 70 stations on Ukrainian railways providing 7,5 million t consignor routing for grain in a year with minimal additional expenses. The assessment of the efficiency of railway transportation routing of grain freights is calculated with use of the developed simulation model. Researches showed that application of consignor routing allows to reduce a turnround cycle for grain wagon in a logistic chain of deliveries up to 27%, and application of the schedule for consignor routes allows to reduce a turn-round cycle up to 62%, in comparison with transportation by car loading. Thus, as showed the calculations executed for one of the directions of grain transportation for export, the necessary operation park of graincarrier wagons is reduced twice, thereby allowing to cut logistic expenses on a delivery of the Ukrainian grain through seaports to the world markets.

Theoretical and experimental research of strength properties of spine beam of freight cars

Abstract: Purpose . The purpose of this paper is to analyze the results of theoretical and experimental studies of the strength properties of rolling stock; search for design tools, modeling, selection, justification of the service life extension of freight cars and their elements. Methodology . The article is based on the finite element method (FEM). It makes possible to completely automate the calculation of mechanical systems, although, as a rule, it requires a much larger number of computational operations than the classical methods of mechanics. The modern level of development of computer technology opens wide opportunities for the introduction of FEM into engineering practice. FEM is implemented in many well-known and widely distributed software products that provide strength analysis of models of machines, mechanisms, structures, including the rolling stock of railways. Findings . The article presents an analysis of the theoretical and experimental studies of the strength properties of rolling stock elements on the example of the spine beam of freight cars; calculations were performed using a modern application program package. The presented example of use of the offered approach has shown its operation capacity and efficiency, as well as correctness of the research direction. The offered approach can be used when solving similar optimization tasks in research and developmental practice of transport mechanical engineering. Originality . The authors proposed me-thod of determining the reliability indicators and solving scientific and applied problem of calculating the elements of freight cars, taking into account the operation features and the loading mode impact. This allows determining their durability at the design stage. There were developed and investigated the models of the spine beam of a freight car, on the basis of which the dependences characterizing the stress-strain state of its elements were obtained. Scientifically substantiated results of the evaluation of strength properties of spine beams of freight cars were obtained depending on their design. The aspects related to the current state and development prospects of railway transport, the use of the software complex in the design and calculation of rolling stock in the railway industry are considered. Practical value . The theoretical and experimental studies of the strength properties of rolling stock elements were considered on the example of a spine beam in a freight car. Calculations were performed using a modern software package. The application of these results will contribute to increase the safety of freight cars and improve the technical and economic performance of railway transport.

Transformation of the Gender Dichotomy of Spirit and Body in Postmodern Philosophy and Culture

Abstract: Purpose. The signification of the theoretical grounds for the conceptual reconstruction of the dichotomy "spirit-body" in the field of postmodern notions in philosophy and culture, the identification of the location of the given dichotomy in the processes of the transition of philosophy from being classical to the postclassical one, simultaneously, culture – to the cultural forms of postmodernity. Theoretical basis. The changing systems of post paradigm relations, radically transforming human life in the postmodern world, represent the obvious transformations of the fundamental conceptual schemes. For postmodern philosophers, the dichotomy "spirit-body" does not mean better interpretation of separate substances any more, but the development of the relationship between mental and physical properties. Feminist philosophers assert that the "spirit-body" opposition occupies the special place among classical dichotomies, as it acquires the key meaning in the patriarchal concepts of masculinity and femininity. In the post modernity, the body and corporality become dominant themes not only in the philosophy and "high" culture, but also in mass culture; at the same time, the emphasis on their common narratives and intertexts testifies to the fundamental transformations that reflect the "condition" of postmodernity. Originality of this research lies in the expose of the specific transformation features of the dichotomy "spirit-body" as a philosophic opposition closely connected with postmodernism and realized in the practices of mass culture. This research is reflectedof the idea of the absoluteness and invariabilityof this duality as thebasicdichotomy of the classical philosophy in its correlation with cultural logic of the postmodernity at the end of the 20 – the beginning of the 21st centuries. Conclusions. With the reinterpretation of the "spirit-body" dichotomy, the body is theorized as a cognitive agent with desires independent of the mind. In postmodernism, the body is the source of charm, and aversion and destruction, and restoration. At the same time, with the growth of the visualization factor and the change in the status of "high" culture, the "turn" in the status of mass culture is created: today both the former and the letter have many common discourses, narratives and intertexts.

Proposals for improving the process of forming programs of reforming the railway transport industry

Abstract: Purpose. The purpose of the work is to develop proposals for improving the process of forming measures and programs for reforming the railway transport industry of Ukraine in the process of European integration based on research, comparison and generalization of information. Methodology. A study of the content and the main provisions of legal acts declaring the conditions for the reform of the railway transport was carried out using analysis and synthesis methods. Methods of the system approach, comparison and generalization of the obtained data allowed developing proposals for improving the process of the formation of activities and programs. Findings. The need for reforming Ukraine's railway transport has been under consideration since 2006, but for a long time reform was limited only to the development of reforming plans and programs. Not being implemented within the framework of one program, the measures were reflected in the next or parallel one, with the corresponding change in the terms. The carried out analysis of their implementation does not allow talking about inactivity or denying the existence of positive changes, however, given the duration of the period 2006-2017, they occur very slowly. This situation requires new approaches to the development of programs and activities, as well as assessing their implementation, one of which is proposed in the work. Originality. The work justifies the need to evaluate the implementation of measures and programs for reforming the railway transport industry by two criteria: legal and practical. The developed basic principles for the formation of programs for reforming and developing the railway transport industry provide an opportunity to receive timely and reliable information on the status of their implementation. Practical value. We obtained the possibilities of constant monitoring of the state of financial support for reforms and directions of use of funds, which will prevent their misuse and significantly accelerate the implementation of certain activities, and then increase their effectiveness.

Mathematical model of unsteady heat transfer of passenger car with heating system

Abstract: Purpose . The existing mathematical models of unsteady heat processes in a passenger car do not fully reflect the thermal processes, occurring in the car wits a heating system. In addition, unsteady heat processes are often studied in steady regime, when the heat fluxes and the parameters of the thermal circuit are constant and do not depend on time. In connection with the emergence of more effective technical solutions to the life support system there is a need for creating a new mathematical apparatus, which would allow taking into account these features and their influence on the course of unsteady heat processes throughout the travel time. The purpose of this work is to create a mathematical model of the heat regime of a passenger car with a heating system that takes into account the unsteady heat processes. Methodology . To achieve this task the author composed a system of differential equations, describing unsteady heat processes during the heating of a passenger car. For the solution of the composed system of equations, the author used the method of elementary balances. Findings . The paper presents the developed numerical algorithm and computer program for simulation of transitional heat processes in a locomotive traction passenger car, which allows taking into account the various constructive solutions of the life support system of passenger cars and to simulate unsteady heat processes at any stage of the trip. Originality . For the first time the author developed a mathematical model of heat processes in a car with a heating system, that unlike existing models, allows to investigate the unsteady heat engineering performance in the cabin of the car under different operating conditions and compare the work of various life support systems from the point of view their constructive solutions. Practical value . The work presented the developed mathematical model of the unsteady heat regime of the passenger car with a heating system to estimate the efficiency of unsteady, transitional temperature states in passenger cars, taking into account the design features of the heating system and the regulatory requirements. This allows the development and implementation of optimal technical characteristics of heating appliances and the construction of an algorithm for controlling their operation in accordance with operating conditions, taking into account the thermal inertia of the car in the transitional modes of heating, on the basis of mathematical modeling.

Water cleaning from residues of medicinal preparations

Abstract: Цель. Основная цель статьи – проанализировать наличие в воде Украины и мира остаточных количеств лекарственных препаратов, а также на основании мирового и собственного опыта предложить методы очистки вод от лекарств. Методика. Исследования выполнены на основании анализа научных источников и отчетных данных о наличии лекарств в воде Украины, европейских стран, США (1999–2017 гг.). Результаты. Проанализированные источники свидетельствуют, что основной экологической угрозой мирового масштаба является наличие лекарств в питьевой воде. Очистные сооружения не приспособлены для обнаружения и разложения лекарственных средств. Во всем мире не предусмотрена борьба с данными веществами. Авторы представляют результаты комплексного рассмотрения вопросов, связанных с определением наличия лекарств в различных водах, их концентраций и наиболее опасных лекарственных препаратов-токсикантов. Медикаменты могут накапливаться не только в организме людей и животных, но и в морской и речной рыбе и т. под. Воздействие даже следовых количеств некоторых лекарств (наркотики, гормональные средства) может оказывать негативное влияние на здоровье более уязвимых слоев населения, особенно детей. Установлено, что главным виновником гормонального загрязнения воды является сельское хозяйство, а именно животноводство. Научная новизна. В работе обобщены имеющиеся и представлены новые методы и технологии очистки воды, такие как: электрохимический, мембранный, адсорбция на основе активированного угля, ультразвуковая обработка в присутствии катализаторов, обработка вод ферментами и персульфатами. Как второй путь снижения количества лекарств в воде предложено создание экологически чистых лекарств. Практическая значимость. Водные проблемы являются главными во всем мире и в Украине в том числе. Нужно предусмотреть дополнительное финансирование для решения проблемы очистки воды от лекарственных препаратов не по остаточному принципу, а по основному финансированию, учитывая то, что вода – это основа жизни на земле, и от качества воды зависит здоровье и жизнь человечества.

Assessment of the railway influence on the heavy metal accumulation in soil

Abstract: Purpose. The scientific paper aims at analyzing the current state of the railway infrastructure soil contamination with heavy metals (HM), namely, the three stations of Prydniprovska railway: Kamianske-Pasazhyrske, Zaporizhzhia-Kamianske and Trytuzna. Methodology. The research object is the soil of the above mentioned railway stations, the research subject is the total content of HM. Sampling was carried out every 15 m between and outside both rails up to the end of railway ties. The total area of the investigated sites is 600 m 2 . The total form of Fe, Pb, Zn, Cu, Ni, Cd and Mn concentration was determined by the atomic absorption spectrometry method. The obtained data were compared with the background concentration of HM for Dnipropetrovsk oblast and the results of analyzing the reference control located at a distance of 250 m from the railway stations. Findings. It is found out that rail transport is a source of HM emission into soil. The findings indicate that the soil state of the Kamianske-Pasazhyrske station corresponds to a low ecological risk and a low degree of pollution, since the station is a passenger one only and pollution occurs mostly due to the friction of wheels and rails and that of the pantograph and overhead system, as well as the pesticide use. The soil contamination of the Zaporizhzhia-Kamianske station is characterized by a considerable potential environmental risk and a very high degree of pollution. This station is a cargo-passenger one, and this pollution level is mainly due to loading and unloading processes. The soil of the Trytuzna station is characterized by an average potential ecological risk and a moderate degree of pollution. Although this station is mainly used for the freight trains reformation, but due to the transportation of large volumes of bulk ore cargoes HM fall into soil. Besides, the station is not electrified. Recommendations for assessment of the soil pollution levels are given. Originality. For the first time the potential ecological risk of soil contamination was determined on the basis of the physical and chemical analysis of the HM content in the soil of the above-mentioned stations. Practical value. The results of the study can be used as a justification of the reasonability of introducing the environmental monitoring programs for the railway land, the environmental protection measures for the soil treatment from HM, correcting the railway exclusion zone, as well as protection of adjacent territories from the propagation and accumulation of the mentioned pollutants. The necessity and urgency of the constant control of the HM content in the railway soil and the relevance of the research continuation in this scientific direction are confirmed on the basis of the received data.

Sensitivity of stresses to the forces acting on the cast parts of freight-car bogie

Abstract: Purpose . To determine the effect of the force components acting in the axle box and the central spring suspension on the stresses occurring in the solebar of the three-piece bogie. Methodology. To assess the effect of the forces acting on the solebar on the stresses in it, we developed a finite element model of the solebar. After that, we carried out an assessment of its stress-strain state under loading conditions corresponding to the І and ІІІ design modes. According to the results obtained, we determined the stress concentration points in the construction, which are selected as check ones for further studies. Also, as checkpoints we took the points corresponding to the sensor locations when estimating the stresses in the solebar during the tests. At the next stage, we applied unit loads in sequence at the interaction points of the solebar with the boxes and the central spring group. To obtain a more accurate result, the unit forces were balanced by the corresponding forces and moments of inertia. With each loading variant, tensors of stresses arising from the action of unit loads were obtained at checkpoints. On the basis of the stress tensors obtained, we determined the corresponding equivalent stresses - the sensitivity coefficients. Findings. The paper determines the stress sensitivity coefficients in the three-piece bogie solebar to external loads acting on the solebar from the side of axle box and central spring group. Based on the results of the assessment of the coefficients obtained, we determined the forces having the greatest influence on individual sections of the solebar. We estimated the possibility of using the obtained results in optimizing the parameters of the bogie spring suspension to increase the strength and durability of the solebar. Originality. For the first time, the effect of individual components of the forces acting on the solebar on the stresses in it has been estimated. Practical value. The obtained result can be used in the design and optimization of three-piece bogies, to improve the solebar durability. The stress tensors obtained can be used to estimate the effect of complex loading on the solebar strength and durability.

Formation peculiarities of financial resources of pjsc «ukrainian railway»

Abstract: Purpose. The need for technological modernization of the railway industry in Ukraine, creation of favorable conditions for investment and introduction of innovations in the industry require significant financial resources. The purpose of the article is investigation of possible sources of attracting financial resources necessary for development of Ukrainian railway transport, in particular, during further organizational arrangements and procedures for the railway industry corporatization to search for ways to optimize them. Methodology. During research the methods of comparison, scientific search, analysis and synthesis were used to study the existing sources of financing for corporations abroad and at Ukrainian enterprises. Findings. Analysis of the existing and search for more efficient sources of financial resources necessary for financing Ukrainian railway transport modernization in the process of the railway industry corporatization is carried out. The growth of the financial results share in the amount of internal own resources is achieved by taking measures to increase profits. A significant part of the economic activities financing can be provided by issuing corporate bonds with the presence of positive effect of the financial leverage. Accounting of the financial leverage effect is an efficient tool for optimizing the structure of the share capital and determining the expediency of loan resources. In the process of corporatization, PJSC «Ukrzaliznytsia» should create an efficient system of financial resources that fully takes into account the specifics of its activities, motivates to increase labor productivity with the ultimate purpose of ensuring the external competitiveness of the Ukrainian railway industry. Originality. Based on the study of scientific and methodological sources, as well as the analysis of sources for financing the economic activities of railway transport, the ways of their optimization are proposed. Practical value. Introduction of the proposed approaches will make it possible to justify the economic feasibility and proportionality of internal and external sources of the railway transport financing under the conditions of corporatization.

Professional Competency of Modern Specialist: Means of Formation, Development and Improvement

Abstract: The modern scientific and methodical approaches to the study and analysis of professional competence that are in line with the state requirements for reforming education and the tendencies of introducing a competent approach as one of the key factors of today's vocational education are analyzed. The emphasis is placed on the fact that implementation of the competence approach should include the use of professional training of real professional tasks with the orientation of future professionals to analyze the results of their own professional activities and decisions. The basic principles of professional training of future managers of economic security are determined. It has been established that the professional training of future managers of economic security should be carried out on a modular basis.

Descartes about Anthropological Grounds of Philosophy in the "Early Writings"

Abstract: Purpose of this work is to find the key to understanding the paradox of Descartes’ way of philosophizing during the recourse to the text of "early writings". Realization of the set purpose involves the consistent solving of such tasks: by referring to the research literature, to outline the forms of transition to modern methodology; to explicate the main reasons for philosophy anthropologization by Descartes; to analyze the role of art as the main form of expressing Descartes’ worldview in the "early writings". Theoretical basis. Studies by Descartes experts and the phenomenological tradition. Originality . The analysis of the "early writings" allows to determine the origins of the main doctrine of Descartes’ philosophizing. Its role is manifested in the course of clarifying the main motives of the anthropological approach of the French philosopher. That entails their rootedness in the Copernican-based scientific revolution of the New Age. A prerequisite for the authentic comprehension of the radical change carried out by Descartes is the attention to the paradigmatic significance of art, which is most fully asserted in the "early writings". It is substantiated that the appeal of young Descartes to the experience of art influences his understanding of science, as well as the awareness of human presence in the development of the scientific picture of the world and the distinction of the main components of human nature – mind and will. Conclusions . During the analysis of the contemporary literature devoted to Descartes, there is outlined the tendency to go beyond the notions of naivety and simplicity of his position, one of the manifestations of which is the increased attention to anthropology. The main motives for its actualization are rooted in the scientific revolution of the New Age, which are the form of completion of the radical worldview change initiated by Copernicus. It is about the vision of man as the main component of the universe, attention thereto in the search for the source point and the decisive authority for the world development, reflection of the thinker’s desire to build his own ethical doctrine based on human nature. While comprehending the "early wri-tings", the author focuses on the interpretation by young Descartes of art as a form of expression of truth, which enables the authentic comprehension of human nature. These ideas became the basis for the further work of the thinker, and today they open up new perspectives of exploring the anthropological foundation for later works.

Constructive Model of the Natural Language

Abstract: The paper deals with the natural language model. Elements of the model (the language constructions) are images with such attributes as sounds, letters, morphemes, words and other lexical and syntactic components of the language. Based on the analysis of processes of the world perception, visual and associative thinking, the operations of formation and transformation of images are pointed out. The model can be applied in the semantic NLP.

Investigation of KPP-5 Rail Fastener Elastic Deformation

Abstract: R. Markul: ORCID 0000-0002-7630-8963; V. Kovalchuk: ORCID 0000-0003-4350-1756; Yu. Hnativ: ORCID: 0000-0001-8862-4202, N. Nastechik: ORCID 0000-0002-4178-6092

Properties of Modified Concrete for Special Purpose Structures

Abstract: Purpose. The paper is aimed at developing the scientific fundamentals of new-generation monolithic concrete technology for special purpose structures by controlling the processes of structure formation of a modified cement system under natural hardening conditions. Methodology. The kinetics of interaction between the cement system and aggregates was evaluated by microcalorimetry. The measurements were carried out continuously for 24 hours after preparation of the mixture. The differential and integral characteristics of the heat release of the solidifying system were recorded. Investigation of the rheological properties of concrete mixtures was carried out on the mixtures with 10...15 cm consistency. The microhardness of contact layers was investigated on concrete cubes with dimensions from 20×20×20 to 50×50×50 mm. When determining the structural characteristics, x-ray phase and differential-thermal analyzes of the concrete cement matrix were used. Infrared spectroscopy was used to determine the effect of physicochemical modification on the cement system. Tensile creep was studied over a wide load range from 0.2 R t to 0.8 R t . Findings. It is determined that the reason for changing the concrete properties of natural hardening is the change in its hygrometric and thermal state, as well as the harmonic fluctuations of these environmental factors. The hygrometry of concrete depends on the thermal moisture conditions of the environment, the type and composition of concrete, the massiveness of concrete elements. An analysis of these factors and experimental data made it possible to establish the exponential dependence of the change in the hygrometric state of monolithic natural hardening concrete. The change in the moisture state of concrete makes it possible to predict its volumetric deformations. Originality . For the first time, the features of the structure formation of a modified cement system are established, consisting in the fact that magnesium chloride hydrate crystals grow rapidly in the space between hydrated clinker minerals, and the resulting mechanical cohesion defines the development of initial strength and rigidity. Since the free growth of crystals is hampered by a lack of space, the crystals mutually intergrow, forming a dense structure, contributing to the growth of strength. The developed organo-mineral modifying complex provides disperse reinforcement of the cement matrix of concrete. Practical value . The obtained dependences of structural concrete stresses make it possible to analyze their effect on the structure of modified concrete: to determine the probability of formation around the filler particles of the plastic flow zone, the material microcrack formation zone, the crack initiation period, the microcrack onset conditions, and the change of elasticity modulus of the material caused by microcracks in its structure. Disperous modification of cement matrix allows to obtain durable concrete of special purpose with design operational properties. The developed binder disperse modification technology, the established features of the structure formation mechanism for the modified cement system, as well as the use of the principle of congruence of a complex of technological influences to the physico-chemical processes of hydration of clinker minerals allowed developing the scientific fundamentals for the special purpose concrete technology. This helps to expand the use of modified concrete in various types of construction.

Efficiency of modernization of wheel-motor blocks (wmb) using anti-friction traction motor support bearings (tmsb)

Abstract: Purpose . The use of anti-friction traction motor support bearings (TMSB) instead of plain friction traction motor support bearings is a priority direction of locomotive development both for newly constructed locomotives and for those in operation. The solution of the set tasks for introduction of wheel-motor blocks (WMB) with anti-friction bearings demanded the search for alternative variants and new technical solutions. The purpose of the article is to determine the feasibility of re-equipping the diesel locomotive wheel-motor blocks with anti-friction bearings through the life cycle calculation ( LCC) . Methodology. The procedure and criteria for assessing the economic efficiency of project (investment) proposals and investment projects approved by the Cabinet of Ministers of Ukraine envisage that the cost-effectiveness analysis of an investment project is carried out according to the following criteria: net present value, internal rate of return, discounted payback period and profitability index. The use of these criteria of economic efficiency fully corresponds to modern principles, theoretical-methodical approaches and world practice in evaluating the efficiency of investments. The evaluation of the technical and economic efficiency of the modernization of the diesel locomotive wheel-motor block is made on the basis of calculation and comparison of the following criteria: the net present value (NPV) of modernization, the internal rate of return (IRR), the profitability index (PI) and the discount payback period. Findings. The results of the calculations of the values of the main criteria show that the innovative project for the modernization of the locomotive provides a high level of economic efficiency. At the same time, the value of the discounted payback period of investments in modernization indicates that it is expedient to carry out this operation if the residual life of the upgraded locomotive of the M62 series is at least 15 months. Originality . Taking into account the specifics of the type of locomotive work in freight traffic, we developed a method to determine the individual components of the average annual economic effect of modernization of the diesel locomotive wheel-motor block, which includes saving of oil costs, repairing and servicing the diesel locomotive wheel-motor unit, as well as change of TMSB brass and saving fuel costs for traction. Practical value . The results of the work make it possible to determine the expediency of modernization of diesel locomotives taking into account the features and conditions of their operation and the specifics of modernization.

Analytical support of financial analysis at the railway transport

Abstract: Purpose . The work is dedicated to systematization of basic directions for financial analysis taking into account the specific features of railway industry. Methodology . In the course of the research there were used the methods of analysis and synthesis to study the content and basic provisions of scientific publications on the chosen topic. Findings . The railway industry has a specific system of financial relations. Knowing the objective development laws of the industry technological system, you can create an appropriate mechanism for managing it and its resources. The selection of the necessary method of analysis and system of indicators, which will provide a comprehensive study and representation of the enterprise activity, is fundamental for the adoption of management decisions. Financial analysis is an important element of analytical work for the needs of modern management. With the help of financial analysis it is possible to determine the place of the enterprise among other subjects of the industry; to assess the structure of capital and the dynamics of enterprise development. Consequently, the quality of the decisions taken completely depends on the analytical substantiation. Financial analysis is carried out according to certain groups of economic indicators, which give an overall assessment of the financial condition of the enterprise, the profitability of its activities and long-term solvency. The analysis of the financial and economic condition is an important part of effective management of the formation, placement and use of rail transport resources. The features of conducting and interpreting the analysis results of the financial condition at the structural units of PJSC «Ukrzaliznytsia» – regional branches, branch affiliates, production units (if they have a balance sheet), – are explained by the specifics of their economic activities. Originality . The obtained results allow us to consider financial reporting as an informational and analytical provision of financial analysis taking into account the specifics of the corporate railway industry relations. The method of financial analysis should be consistent with the strategic objectives of the business entity, which are determined by the system of strategic management and investment and financial planning of the railway industry. Practical value. The assessment of the financial condition of an enterprise can be objectively carried out using a system of indicators that take into account the technological specificity of the rail transport, comprehensively characterizing the results of its activities and reflect the competence of management through the quality of the decisions taken.

Usage of construction-oriented software scad for analysis of work of machine-building structures

Abstract: Мета. У випадку аналізу роботи машинобудівних конструкцій безпосереднє використання будівельно-орієнтованих програмних розробок є неможливим, оскільки ідеологія та методика рішення різноманітних задач у будівництві та машинобудуванні різняться. Тому при проведенні практичних розрахунків виникає необхідність у певному коригуванні закладених у програмні комплекси підходів та їх адаптації до машинобудівної галузі. Викладення авторського досвіду використання будівельно-орієнтованого програмного комплексу SCAD for Windows для аналізу роботи різноманітних машинобудівних конструкцій, їх вузлів та агрегатів і є безпосередньою метою публікації. Методика. На протязі значного терміну часу автор займався аналізом роботи будівельних, переважно тонкостінних, сталевих конструкцій за допомогою методу скінчених елементів (МСЕ) на базі програмного комплексу SCAD for Windows. Паралельно з цим було розглянуто значну кількість машинобудівних конструкцій, в тому числі одиниць рухомого складу залізниці. Більшість із таких задач переростали в науково-пошукову проблему, яку необхідно було всебічно дослідити та проаналізувати перед тим, як надавати конструкторські рекомендації. Результати. В публікації представлені більше десятка різноманітних задач, характерних для галузі машинобудування, з якими автору довелося мати справу. Серед них статична та квазістатична задачі, задача руху в часі, контактна задача, задача розвитку тріщин, фізична та геометрична нелінійності. Відповідно до кожної з цих задач наведені основні проблеми, особливості та практичні прийоми, напрацьовані під час дослідження, а також в якості ілюстрації представлені побудовані скінченно-елементні моделі. Наукова новизна. Узагальнено досвід використання будівельно-орієнтованого програмного продукту на базі методу скінчених елементів для аналізу роботи машинобудівних конструкцій. Викладено низку практичних прийомів та підходів до вирішення різноманітних задач у машинобудівній галузі. Практична значимість. Застосування наведеної інформації, методів та підходів дозволяє не тільки вирішити конкретні практичні задачі машинобудівної галузі, а й отримати коректні та практично прийнятні рішення.

Mathematical model of dpkr-2 dyzel train car

Abstract: Purpose . In order to study the dynamic phenomena arising when rolling stock moves along a rail track both in the straight and curved track sections, the article is aimed to construct a mathematical model of DPKr-2 diesel train car. It will be constructed on the basis of mechanical model of this car of Kryukiv Railway Car Building Works. Methodology . To construct a mathematical model a system of 38 differential equations of the diesel train movement is formed. When it is used a pneumatic spring in the core stage of spring suspension, its equivalent mechanical mo-del is presented as Kelvin-Voigt knot. It includes a parallel elastic element and an element of viscous friction. Rail track flexibility is taken into account by elastic and dissipative elements. During simulation it was assumed that the wheel pair and the track weight interacting with it were moving intact. Geometric inequalities of the left and right rails were accepted as disturbances when studying the forced vertical and horizontal oscillations. Findings . On the basis of the adopted mechanical model of the diesel train car we constructed the mathematical model consisting of 38 differential equations of motion . Originality . For the first time, for the DPKr-2 diesel train car we developed its spatial mathematical model taking into account the features of the interaction of individual elements of its construction and the possibilities of the rail track depression. When constructing the mathematical model, it was proposed to take into account the flexibility of the rail track by elastic and dissipative elements. Originality . The mathematical model of the diesel train car will be used for studying the dynamic phenomena and determining the dynamic loads of structural elements during operation. The study of these phenomena is necessary for optimal choice of the scheme and parameters of rolling stock equipment, in particular antivibration devices (spring suspension, horizontal, longitudinal and transverse joints of wheel pairs with the bogie frame, bogie with the body), as well as for reduction of dynamic forces acting on the elements of rolling stock construction and rail track.

Railway transport risk management and insurance

Abstract: The article considers and analyzes railway transport risks. The general risk classification related to the passenger traffic has also been improved. In addition, for more sophisticated study of risk management and insurance issue, the features of railway transport insurance have been identified; the rules of railway transport voluntary insurance of various insurance companies are analyzed. As the result, it was constructed an improved classification of factors influencing the efficiency of the passenger train plying and associated with risks for passenger traffic, based on the studies carried out. The need to take into account the main factors affecting the efficiency of passenger transportation along with railway transport risks were noted. This should ensure an increase in the efficiency of passenger transportations and their competitiveness in the transport market of the country.

Prediction of microclimate near small architectural constructions

Abstract: A mathematical model has been created for predicting the microclimate parameters in the work area located directly near the motorway in the presence of a «temporary building» and in its absence. A numerical model has been developed to determine the velocity field of the air flow in the area of employee's location, taking into account the location of the remote trading place, the “temporary building” without an eaver and with an eaver based on the Navier–Stokesequation. To predict the concentration level in the microzone, two-dimensional equation of impurity transport in atmospheric air is used. Numerical integration of the equation of hydrodynamics and mass transfer is carried out with the help of an implicit difference scheme. Three variants of the location of trading place in the zone of motorway influence are considered: the first option – the seller performs the trade of outbound goods without the presence of a “temporary building”; the second option is that the seller performs the trade of outbound goods at the“temporary building”, which does not have an eaver; the third option is that the seller carries out the trade of outbound goods at the“temporary building”, which has an eaver. The analysis of changes in airflow velocity and concentration of pollutant at the level of the head of employee (locally), depending on the location of the place of trade. The presence of a “temporary building” reduces the speed by 2 times and the concentration by 1.5 times, the presence of an eaver in the same structure reduces the speed by 5 times and the concentration by 1.75 times, relative to the situation when the eaver is absent. It has been revealed that the eaver influences the change in pollutant concentration, but plays more significant role in reducing the speed of the air flow, providing comfortable conditions for the microclimate in the work area. Long or systematic stay in such a work area will not affect the worker’s state of health, can ensure its high performance and comfort in the working area.

Optimal structural reservation of technical systems

Abstract: Purpose . The purpose of the article is to give designers of highly reliable technical systems that do not have special knowledge in the field of optimization and programming skills, a simple and accessible mathematical tool for choosing the optimal solution for structural redundancy of systems. Methodology. The article poses the problem of optimal structural redundancy of technical systems. Two typical redundancy schemes are considered: a) a separate "hot" backup scheme; b) a separate "cold" backup scheme. The computational models for estimating the reliability of redundant systems are formulated. We offer optimization models that allow us to find a rational option for reserving a system that is being designed, taking into account conflicting requirements for its reliability and cost. These models are numerically implemented in the operating environment of the Excel spreadsheet as applied to the main object, consisting of 7 elements. The optimal variants of reserving this object according to the "hot" and "cold" separate reservation schemes are given. Findings. Calculated models for estimating reliability, as well as models for optimizing the systems reserved for the "hot" and "cold" separate backup schemes, have been developed. With the use of the Excel spreadsheet, the optimal options for reserving 7 element objects are found for separate "hot" and "cold" backups. Originality . New computational models for estimating the reliability of redundant systems are proposed, as well as optimization models developed on the basis of these, which are formulated using the decomposition of unknown initial problem of structural redundancy into binary components. In this case, the obtained optimization models belong to the class of problems of non-linear mathematical programming with binary variables, for the numerical solution of which (even for a sufficiently large dimension) well-known packages of applied computer programs, in particular, the MS Excel spreadsheet, are well adapted. Thus, the process of solving the initially very complicated problem of optimal structural redundancy is much simpler and reduced to performing elementary actions in the corresponding software interfaces. Practical value. The proposed calculation models for estimating the reliability of redundant systems, models for optimal structural redundancy, and the methodology for their formation, in order to simplify further numerical implementation, can be useful in solving problems of ensuring the reliability of technical systems in the early stages of their design.

Territorial risk assesment after terrorist act: express model

Abstract: Purpose. The paper involves the development of a method to assess the territorial risk in the event of a terrorist attack using a chemical agent. Methodology. To describe the process of chemical agent scattering in the atmosphere, ejected in the event of a terrorist attack, the equation of mass transfer of an impurity in atmospheric air is used. The equation takes into account the velocity of the wind flow, atmospheric diffusion, the intensity of chemical agent emission, the presence of buildings near the site of the emission of a chemically hazardous substance. For numerical integration of the modeling equation, a finite difference method is used. A feature of the developed numerical model is the possibility of assessing the territorial risk in the event of a terrorist attack under different weather conditions and the presence of buildings. Findings. A specialized numerical model and software package has been developed that can be used to assess the territorial risk, both in the case of terrorist attacks, with the use of chemical agents, and in case of extreme situations at chemically hazardous facilities and transport. The method can be implemented on small and medium-sized computers, which allows it to be widely used for solving the problems of the class under consideration. The results of a computational experiment are presented that allow estimating possibilities of the proposed method for assessing the territorial risk in the event of a terrorist attack using a chemical agent. Originality. An effective method of assessing the territorial risk in the event of a terrorist attack using a chemically hazardous substance is proposed. The method can be used to assess the territorial risk in an urban environment, which allows you to obtain adequate data on possible damage areas. The method is based on the numerical integration of the fundamental mass transfer equation, which expresses the law of conservation of mass in a liquid medium. Practical value. The proposed method for assessing the territorial risk in the event of a terrorist attack using a chemical agent can be used to calculate the affected areas near administrative buildings, centers and other socially significant facilities.