Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan

About: Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan is a education organization based out in Dnipro, Ukraine. It is known for research contribution in the topics: Track (rail transport) & Bogie. The organization has 736 authors who have published 655 publications receiving 1468 citations. The organization is also known as: Institute of Railway Transport Engineers.

The measurement methodology improvement of the horizontal irregularities in plan

Abstract: Purpose . Across the track superstructure (TSS) there are structures where standard approach to the decision on the future of their operation is not entirely correct or acceptable. In particular, it concerns the track sections which are sufficiently quickly change their geometric parameters: the radius of curvature, angle of rotation, and the like. As an example, such portions of TSS may include crossovers where their component is within the so-called connecting part, which at a sufficiently short length, substantially changes curvature. The estimation of the position in terms of a design on the basis of the existing technique (by the difference in the adjacent arrows bending) is virtually impossible. Therefore it is proposed to complement and improve the methodology for assessing the situation of the curve in plan upon difference in the adjacent versine. Methodology. The possible options for measuring horizontal curves in the plan were analyzed. The most adequate method, which does not contradict existing on the criterion of the possibility of using established standards was determined. The ease of measurement and calculation was took into account. Findings. Qualitative and quantitative verification of the proposed and existing methods showed very good agreement of the measurement results. This gives grounds to assert that this methodology can be recommended to the workers of track facilities in the assessment of horizontal irregularities in plan not only curves, but also within the connecting part of switch congresses. Originality. The existing method of valuation of the geometric position of the curves in the plan was improved. It does not create new regulations, and all results are evaluated by existing norms. Practical value . The proposed technique makes it possible, without creating a new regulatory framework, to be attached to existing one, and expanding the boundaries of its application. This method can be used not only for ordinary curves, but for very short sections, the curvature of which changes abruptly to its opposite value.

The Role of Libraries as Publishers in the Open Education Landscape: Reflecting Modern World Practice of Open Textbooks

Abstract: Objective . The study aims to analyse the experience of university libraries in different countries in working with the Open Textbook (OT) and to consider the prospects of creating a similar pilot project in Ukraine. Methods . The analysis covered the world publications (journals, books, conference proceedings, posts on social networks) in the field of Library and Information Science, devoted to the role of libraries in OT support, that have appeared since 2014. The author studied the aspects revealing that publication, namely OT, support services are areas with great potential for the future development of academic / university libraries. Results . Numerous evidence is presented that the topic of library as a publisher in OT support is most developed in the universities and colleges in economically developed countries, especially in the USA, Canada, Australia, and Great Britain. Library strategies for OT projects have been identified. The author clarified the nature of the initiatives and partnerships of libraries in supporting OT, as well as the basic services and roles of libraries in these projects. Conclusions . Today, the global practice of Scholarly Communication has enough evidence that the functions of the Library, lost in the course of evolution, as a Knowledge Publisher have returned under its “roof” and supplemented the existing function of Knowledge Managers. Digital Library Publishing (DLP) services in OT support help to change the learning environment and life of students (including persons with disabilities), pedagogical practices of teachers by means of free textbooks with an open license, as well as to receive reputation benefits for the university, improving the image of the latter. The possibility of eliminating systemic inequalities in access to academic resources increases the significance and changes the role of libraries in open education. The successes of Ukrainian librarians in supporting digital scholarly communication initiatives and the successful implementation of Open Access support projects (repositories, e-journals, e-conferences) give confidence that they can act as initiators and key partners in creating affordable textbooks.

Numerical prediction models for air pollution by motor vehicle emissions

Abstract: Цель . Научная работа предполагает: 1) разработку 3 D численных моделей, которые позволяют рассчитывать процесс загрязнения атмосферного воздуха выбросами автотранспорта; 2) создание моделей, которые давали бы возможность прогнозировать уровень загрязнения атмосферного воздуха в условиях городской застройки. Методика. Для решения задачи по оценке уровня загрязнения атмосферного воздуха выбросами автотранспорта используются фундаментальные уравнения аэродинамики и массопереноса. Для решения дифференциальных уравнений аэродинамики и массопереноса используются конечно-разностные методы. Для численного интегрирования уравнения потенциала скорости применяется метод условной аппроксимации. Уравнение для потенциала скорости, записанное в разностном виде, расщепляется на два уравнения, причем на каждом шаге расщепления неизвестное значение потенциала скорости определяется по явной схеме бегущего счета, при этом сама разностная схема – неявная. Для численного интегрирования уравнения рассеивания выбросов в атмосфере применяется неявная попеременно-треугольная разностная схема расщепления. Выбросы от автотрассы моделируются серией точечных источников заданной интенсивности. Разработанные численные модели составляют основу созданного пакета прикладных программ. Результаты. Разработаны 3 D численные модели, которые относятся к классу « diagnostic models ». Данные модели учитывают основные физические факторы, влияющие на процесс рассеивания вредных веществ в атмосфере при выбросах от автотранспорта в городе. На основе построенных численных моделей проведен вычислительный эксперимент по оценке уровня загрязнения воздушной среды на улице. Научная новизна. Авторами разработаны численные модели, которые позволяют рассчитать 3 D аэродинамику ветрового потока в условиях городской застройки и процесс массопереноса выбросов от автотрассы. Выполнены расчеты по определению зоны загрязнения, которая формируется возле зданий, расположенных вдоль автомагистрали. Практическая значимость. В работе рассмотрены эффективные численные модели, которые могут быть применены при разработке мероприятий по охране окружающей среды при эксплуатации автомобильного транспорта в городе. Разработанные модели позволяют оценить размеры, форму и интенсивность зоны загрязнения возле автомагистрали.

Devising a procedure for assessing the subgrade compaction degree based on the propagation rate of elastic waves

Abstract: This paper reports the analysis of the methods for estimating the technical condition of the subgrade underneath a constructed railroad track or road during its operation. The study results have proven that the issue related to monitoring and controlling high-quality compaction of a heterogeneous subgrade remains relevant and requires the construction of reliable experimental methods for assessing the subgrade degree of compaction. A procedure for determining the compaction of subgrade in the laboratory has been devised, based on inertial microcomputer technologies, which makes it possible to assess the degree of compaction of subgrade soils depending on the propagation rate of an impact's elastic waves. An experimental study has been performed into the propagation rate of elastic waves across a homogeneous subgrade made of coarse-grained sand and a heterogeneous subgrade made of coarse sand with a layer of clay in the middle of the prism. The study results established that the propagation rate of an elastic wave in a heterogeneous subgrade accepts a lower value than the rate of wave propagation in a homogeneous subgrade. Through the dynamic interpretation, by using a discriminant statistical analysis, the characteristic features have been defined in the distribution of accelerations in the body of the homogeneous and heterogeneous subgrade, depending on the degree of compaction, which would make it possible to monitor the state of the subgrade during operation. As the degree of the subgrade soil compaction affects the technical condition of roads

Inequalities research of the track at the railroad crossings

Abstract: Purpose. The intersection of highways and railways in one level – railway crossing, is a zone of increased danger for rail and road transport. Nearly half of all crossings are available on the main directions of passenger transportation. From this comes the problem of maintenance and service locations of intersection roads and railways. The purpose of this work is to evaluate the processes of emergence and development of inequalities in the area of railroad crossings and identify the factors that cause them. Methodology. The presence of derogation from the plan and profile within the railway crossing and approaches to it reduces evenness of riding and passenger comfort. Today, there are various possibilities for shooting natural geometry of a railway track. For research on a large number of areas during long service life, the tape of a track measuring car remains the most convenient. However, this tool is directed to assess the state of the railway line and does not determine the exact geometrical position. When trying to determine valid outlines of the track inequalities on track measuring tape, some difficulties arise . Findings . Performed statistical analysis showed a steady trend of growth of inequalities in the area of the railway crossings. Generally, the level of inequalities in the vertical plane increases in1.3 − 3.2 times and in 1.2 − 2.0 times in the horizontal plane (compared with areas that are outside crossing). During the deflection lines of action in the area of railroad crossing concrete slabs work as ribs that limit deflections of rail-tie grating. When placing the wheels of the bogie before (or after) and within crossing the calculated modulus of elasticity under the rail base, brought to the point of wheels contact can vary up to 3 times. Originality. Issues of the assessment and investigation of inequalities on track started to be developed. The resulting statistics on inequalities accumulation gauge in the zone of crossing were obtained. Analytical research changes in the characteristics of stress and deformation of the track at the site of the conclusion of the railway crossing were presented. Practical value. Obtained results will be useful for measures to improve the evenness riding of trains and increase the comfort level of passengers.