Science and Transport Progress Bulletin of Dnipropetrovsk National University of Railway Transport
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Published By Dnipropetrovsk National University Of Railway Transport

2307-6666, 2307-3489

Author(s):  
О. A Hodoskina ◽  
О. Y Moiseienkova

Purpose. Currently, the organization of sales at the enterprise is the main and continuous process that provides the enterprise with its economic efficiency and bringing the goods to the consumer. The purpose of this work is to analyze and compare modes of transport and its role in the marketing of products by an enterprise. Methodology. To build a model for the marketing activity of an enterprise, as well as when modeling the mechanism of functioning of its organizational, economic and production structure and the place of transport in the structure of an industrial enterprise, elements of economic and mathematical modeling were used. Analysis of the data obtained allows you to choose the best method of transportation, which is extremely important to ensure that the needs of the enterprise, as well as the needs of consumers, are met. Findings. Marketing and logistics services of the enterprise need, having studied all the advantages and disadvantages of all types of transport, to choose the most optimal mode of transport when transporting goods. For the sale of its products, the enterprise should take into account that over time, the costs of different types of transport may change, and the transportation schemes should be revised. The paper compares the modes of transport and the structure of freight turnover by mode of transport (as a percentage of the total). Originality. The use of a mathematical apparatus in the construction of functional dependencies that make up a general economic and mathematical model that characterizes the organization of the marketing activities of an enterprise will allow not only to identify «weak» points, but also to adjust the marketing policy of the enterprise accordingly, relying not on abstract conclusions, but on the obtained clear dependencies. Practical value. The result is, first of all, a reduction in costs in the marketing policy of the enterprise and an increase in competitiveness, an increase in profits and maximum satisfaction of consumer requirements.


Author(s):  
A. Y Kuzyshyn ◽  
S. A Kostritsia ◽  
Yu. H Sobolevska ◽  
А. V Batih

Purpose. Taking into account the production and commissioning of modern high-speed rolling stock, the authors are aimed to analyze the currently created mathematical models describing the dynamic behavior of the air spring, systematize them and consider the advantages and disadvantages of each model type. Methodology. For the analysis, a comparative chronological method was used, which makes it possible to trace the development of several points of view, concepts, theories. In accordance with the adopted decision equations, the existing models of air springs were divided into three groups: mechanical, thermodynamic and finite-elements. When analyzing mathematical models, the influence of a number of parameters on the dynamic behavior of the air spring, such as disturbing force frequency, heat transfer, nonlinear characteristics of materials, the shape of the membrane, etc., was considered. Findings. A feature of mechanical models is the determination of input parameters based on the analysis of experimental results, requires access to complex measuring equipment and must be performed for each new model of an air spring separately. Unlike mechanical models, which allow taking into account the damping effect of an air spring in the horizontal and vertical direction, thermodynamic models are mainly focused on studying the dynamic behavior of an air spring in the vertical direction. The use of the finite element method makes it possible to most accurately reproduce the dynamic behavior of an air spring, however, it requires significant expenditures of time and effort to create a finite element model and perform calculations. Originality. Mathematical models of the dynamic behavior of an air spring are systematized, and the importance of their study in conjunction with a spatial mathematical model of high-speed rolling stock is emphasized. Practical value. The analysis of the mathematical models of the dynamic behavior of the air spring shows the ways of their further improvement, indicates the possibility of their use in the spatial mathematical model of the rolling stock in accordance with the tasks set. It will allow, even at the design stage of high-speed rolling stock, to evaluate its dynamic characteristic and traffic safety indicators when interacting with a railway track.


Author(s):  
A. V Radkevych ◽  
M. I Netesa ◽  
A. M Netesa

Purpose. The urbanization development in the twenty-first century is characterized by increasing the share of multifunctional infrastructure complexes among the total volume of new and renovated construction. Projects with a developed stylobate part are characterized by significant demand, as well as placing parking lots in the space of underground floors. Such solutions make it possible to effectively use the underground space while minimizing the filling of 1–5 floors. The latter requirement is typical for the construction of historic centers, where urban restrictions regulate the maximum height of the building. The research is aimed at increasing the efficiency of works provided they are combined during the arrangement of underground phase of multifunctional complexes, which are built in the historic part of cities, in a densely built-up area and extremely limited space. Methodology. The authors reviewed the world experience in the installation of multifunctional complexes and introduced best practices in organizational and technological solutions during the development of design and technological documentation for the arrangement of underground phase of the object «New construction of a multifunctional complex with parking at 25 Volodymyra Vernadskoho Street, Dnipro.» The main construction processes of the underground phase arrangement in difficult conditions of compacted construction are considered and the critical elements during their design are determined. The technological sequence of performing related works by various contractors has been improved in order to create a time reserve and increase the reliability of the entire technological process. Findings. Organizational and technological solutions have been identified that allow combining construction and installation processes of underground phase of multifunctional complexes with a significant number of subcontractors under conditions of compacted construction, as well as under complex hydrogeological conditions or during construction in the historic buildings of the central part of cities. Originality. The authors for the first time conducted research in the field of underground phase arrangement given the location of construction equipment in the limited space of the construction site in the historic part of Dnipro and proposed a number of solutions to increase the reliability of the main construction process. Practical value. Based on the results obtained, one can correct the location of construction equipment and determine the rational sequence of construction and installation works, as well as predict the further development of construction technology. These studies can be useful during the study of disciplines «Technology of Construction Production», «Technology of special works», for the organization of scientific and practical seminars, refresher courses and more.


Author(s):  
N. O Dankevych ◽  
M. V Piatnytsia

Purpose. The authors aim to assess the reliability and technical diagnostics of the bridge structure, as well as to develop the methods for eliminating defects and restoring the serviceability of damaged building structures, as most accidents occur due to unsatisfactory technical condition of structures and their significant wear due to expiration of the standard service life. Methodology. An important role in the study is played by the formation of knowledge and skills of using a modern engineering approach to the survey of building structures in order to restore their serviceability. Inspections of construction sites are carried out in accordance with the rules set by the relevant regulations. Defects and damages are described in inspection materials with the indication of the possible reasons of their occurrence and forecasting their further influence on reliability and durability of construction. Findings. The analysis of scientific research and normative documents reflecting a problem of the operation safety increase of buildings and structures and estimation of a technical condition of structures is carried out in work. Methods of assessment of reliability and technical diagnostics of bridge constructions are applied. The results of the inspection are substantiated and recommendations are developed to ensure the serviceability and increase the service life of damaged structures of the object of study. Originality. Based on the design and technological documentation, normative base, scientific research, the model of competent systematization of the construction inspection data is obtained. Attention is paid to the timely major, as well as current medium repairs to improve the technical condition of the bridge elements, and in some cases the entire structure. Practical value. Application of the survey methods – visual and instrumental – allowed formulating the conclusions and recommendations aimed at widespread implementation in practice of assessing the reliability and technical condition of structures.


Author(s):  
Y. E Arutiunian

Purpose. The article is aimed to create scientific tools based on the analysis of modern innovative approaches and tools to improve the processes of construction organization in the conditions of dense urban development using logistics, which has modern concepts of improving the corresponding processes. Methodology. A systematic analysis of scientific works in terms of problems of organization of construction processes taking into account the conditions of dense development, which serves as a platform for the introduction of innovative tools based on the field of logistics knowledge. Findings. The expediency of using logistical approaches and concepts is substantiated, taking into account external factors and limitations that are caused by the environment and configuration of the site, causing difficulties for the internal organization of construction. Logistics tools (approach) allow more efficient use of scientific and practical potential in the further development of methods for improving organizational and technological solutions of construction production under conditions of the functional and planning infrastructure of cities. Principles of logistics will allow to balance construction production in the conditions of dense building; to use flexible tools as an opportunity to make changes in the schedule of material purchase, changes in terms of delivery of building materials, designs, details; minimize stocks of building materials. Originality. Based on scientific research, a model of optimization of organizational construction processes is presented, taking into account the conditions of dense urban development and functional and planning infrastructure of cities. A qualitatively new specialized scientific and practical sub-branch of knowledge, construction logistics, was created for complex conditions of urban development to perform organizational and technological processes of new construction. Practical value. The use of logistics approaches will improve and optimize the processes of construction organization, taking into account the essential factors of functional and planning infrastructure of the city, in which it is necessary to make rational management decisions. Flexibility, alternativeness of production and economic situations and transport networks during the complex organizational and technological processes of construction make it possible to reduce the cost of construction and installation works and help reduce the duration of construction.


Author(s):  
O. S Kuropiatnyk ◽  
B. M Yakovenko

Purpose.The main article purpose is to develop and implement the method for identifying the correspondence between the text and the program algorithm represented in the form of a flowchart. As part of the method work conversion of the input data in the graph representation is performed by means of constructive-synthesizing modelling. Methodology. To compare the program text and flowchart, we constructed a mathematical model for converting the program code into a graphical representation on the basis of control structures. To build the model, the apparatus of constructive-synthesizing modeling and its methods were used: specialization, concretization, interpretation and implementation. The graph representation of the text is created taking into account the control operators; the flowcharts are created using a json file containing the description of the diagram elements and their links. To compare the graphs we use the breadth-first search algorithm with the number of identical vertices being counted. To obtain the software implementation of the developed method and models we used the technology of object-oriented programming and CASE-technologies, which are based on the unified modeling language UML. Findings A method is proposed to present the text and the flowchart of the program in a uniform format of the directed graph (control graph) and to evaluate their correspondence by the number of identical vertices. For its formalization and automated usage, we developed constructive-synthesizing models of input data transformers. The program application was developed based on the models and the method. Originality. The methods of constructive-synthesizing modeling in the tasks of processing texts written in artificial languages were further developed. We developed the system of constructors, which transforms text program in C++ into a control graph. Practical value. The results are significant for solving such tasks as assembling program texts for borrowings detection, determining the correspondence of the program algorithms and their software implementations to improve coding skills. The graph representation produced by the developed system of constructors can be used for investigation of influence of optimization and code refactoring on the program complexity using McCabe's metrics.


Author(s):  
A. A Shuvaiev

Purpose. The main purpose of the work is to define and substantiate the principles, functional requirements and objectives of the implementation of information and analytical support for the management of waste streams of construction and wracking as secondary resources; development of the organizational and functional structure of the information-analytical management system, which would satisfy the conditions for the introduction of a logistical approach within the framework of integrated management of construction waste streams and became the basis for creating a single information platform. Methodology. As a methodological basis for the research of the process of managing the secondary resources streams and reversible streams in the construction industry, a logistic approach is used. It involves the analysis of factors influencing the system and study of its dynamic behavior as a complex adaptive system. The system approach in the development of information-analytical management systems involves solving the following tasks: development of a functional model of the management system of construction and wracking waste streams; construction of interaction matrices of automated processes and data routing processes; modeling the logical architecture of the data warehouses; development of a software and hardware set. Findings. The main tasks of developing information support for the logistics management system of construction and wracking waste streams are substantiated. The integration into the system of the following functional blocks is proposed: database formation; block for estimating the total economic costs of the process; environmental damage assessment blocks; information risk assessment; evaluation of alternative methods of waste stream management; optimal route formation block; visualization block. Based on the generalization of requirements and possibilities of the functionality analyzed information-analytical systems and requirements which would provide efficiency of construction waste streams management, the organizational-functional structure of the system of information-analytical management is proposed. Originality. The work gives reasons for the inclusion in the list of functional blocks of the organizational and functional structure of the information-analytical management system, which should be the basis for creating an information platform for the management of construction and wracking waste streams, environmental and information risk assessment. Practical value. Implementation within the information-analytical management of environmental damage assessment (as part of the efficiency assessment of the construction waste streams) and information risk assessment (as a tool of logistical approach) will provide the ability to predict key system indicators, make optimal decisions aimed at maximum inclusion of construction waste streams in the system as a potential secondary raw material, a sufficient level of economic and environmental efficiency with the optimal level of logistics costs.


Author(s):  
О. O Zhevaho

Purpose. This paper presents the findings of a review of the literature published in the twenty-first century in order to identify and analyze the current state of tools that track developer interactions with integrated development environments, as well as to recommend future research directions based on the actual state. Methodology. By systematically searching in five digital libraries we conducted a systematic review of the literature on data collection tools from integrated development environments published in the twenty-first century. Fifty-five papers were selected as primary studies. Findings. 55 articles were analyzed and the findings show that using an integrated development environment to collect usage data provides more insight into developer activities than it was previously possible. Usage data allows us to analyze how developers spend their time. With usage data, you can learn more about how developers create mental models, investigate code, conduct mini-experiments through trial and error, and what can help everyone improve performance. The research community continues to be highly active in developing tools to track developer activity. The findings indicate that more research is needed in this area to better understand and measure programmer behavior. Originality. For the first time, systematization and analysis of tools for tracking programmer's behavior in an integrated development environment have been carried out. Practical value. Our study contributes to a better understanding of the current state of research on programmer behavior in integrated development environments. An analysis of the study can help define a research agenda as a starting point for the creation of a novel practical tool.


Author(s):  
V. V Burchenkov

Purpose. The main purpose of the work is to determine and classify the heated cars’ boxes based on the probability of appearance of roller and cassette type boxes in the classes of heated and overheated boxes, as well as the laws of probability density distribution of the recognition signs of normally heated and overheated roller and cassette type boxes. Methodology. The operation features of freight cars with cassette type axle boxes with increased operating heating have been investigated. The methodology of assessing the probability of recognition errors was proposed, which takes into account the fact that sets of normally heated and overheated boxes consist of subsets of boxes with different types of bearings. A system of equations is obtained, the roots of which represent еру values that minimize the recognition probability of the errors of the heated boxes. Findings. It was found out that with some methods of determining the bearing type, for example, by the average value of the ranges of thermal image for each car, the probability of erroneous selection may depend on the probability density distribution of the sign for bearings of different types and the threshold value of this sign. The optimal thresholds for detecting the overheated roller boxes in comparison with the optimal thresholds for detecting overheated cassette boxes were determined. It has been established that the pass of an overheated cassette bearing, provided that the type of bearing is determined correctly, is less likely to lead to an accident than if the cassette box is classified as a roller box. The rejection criteria of axle boxes according to their heating temperature difference on one of the wheel set axis for three variants of settings of the alarm system according to an arrangement of multipurpose complexes of technical means (CTM) were formulated. The practical implementation of this method of adjusting the CTM settings for the Minsk branch of the Belarusian Railways was demonstrated. Originality. A system of equations is obtained, which allows finding the optimal values of temperature thresholds for the detection of overheated roller and cassette boxes under the assumption that the error probabilities in the selection of boxes by their types are known and constant. Practical value. The developed method of adjusting the alarm settings of CTM makes it possible to significantly reduce unjustified train delays and the number of car uncouplings.


Author(s):  
A. O Lovska ◽  
O. V Fomin ◽  
A. V Rybin

Purpose. The work aims to investigate dynamic loading of the supporting structure of a gondola car with an elastic-viscous filler in the center sill by means of mathematical modeling. Methodology. Mathematical modeling of the dynamic loading of the supporting structure of a gondola car with a closed center sill filled with a filler with elastic-viscous properties has been carried out. The case of the highest load on the supporting structure of the gondola car in operation is taken into account – a shunting collision, taking into account the action of a load of 3.5 MN on the rear stop of the automatic coupler. To determine the dynamic loading of a gondola car, a mathematical model formed by prof. G. I. Bohomaz was used. However, within the framework of this study, the model was refined by adapting it to the determination of the dynamic loading of a gondola car. It also takes into account the friction forces arising between the center plates of the body and the center pivots of the bogies, as well as the properties of the energy-absorbing material. The solution of the mathematical model was carried out in the MathCad software package. In this case, the differential equations of motion were reduced to the Cauchy normal form, and then integrated using the Runge-Kutta method. Initial displacements and speeds are taken equal to zero. The calculation was carried out on the example of a universal gondola car model 12-757 built by Kriukivskyi Carriage Works PJSC (Kremenchug) on standard bogies 18-100. Findings. Accelerations are obtained as components of a dynamic load acting on a gondola car with a closed center sill structure filled with an elastic-viscous filler. It was found that with the stiffness of the center sill filler of 82 kN/m, as well as the viscous resistance coefficient of -120 kN∙s/m, the maximum accelerations of the gondola car supporting structure is about 37 m/s2 (0.37g). Originality. A mathematical model is proposed for determining the dynamic loading of a gondola car with a closed structure of a center sill filled with an elastic-viscous filler. The model makes it possible to obtain accelerations as the components of the dynamic loading acting on the supporting structure of the gondola car, taking into account the improvement measures during a shunting collision. Practical value. The results of the research will help to reduce the damage to the supporting structures of gondola cars in operation, reduce the cost of their maintenance, create developments in the design of innovative structures of rolling stock, as well as increase the efficiency of its operation.  


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