Кафедра "Вища математика" ДІІТ (з 2022 року кафедра увійшла до складу факультету Будівництво, архітектура та інфраструктура)
Permanent URI for this community
ENG: Department "Higher Mathematics" DIIT (since 2022, the department moved to the warehouse of the faculty Budіvnitstvo, architecture and infrastructure)
Browse
Browsing Кафедра "Вища математика" ДІІТ (з 2022 року кафедра увійшла до складу факультету Будівництво, архітектура та інфраструктура) by Author "Bodnar, Borys Ye."
Now showing 1 - 5 of 5
Results Per Page
Sort Options
Item Choosing the System of Locomotive Maintenance in View of the Effect of Dependent Failures(Дніпропетровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2018) Bodnar, Borys Ye.; Ochkasov, Oleksandr B.; Hryshechkina, Tatiana S.; Bodnar, Yevhen B.ENG: Purpose. Improving the efficiency of the use of locomotives by choosing a rational maintenance system that takes into account the assessment of the effect of dependent failures on the cost of their life cycle is the main purpose of this paper. Methodology. The relevance of introducing LCC (life cycle cost) approaches in locomotive facilities is explained by the introduction of new locomotives with on-board control and diagnostic systems, as well as the development of the theory of traction rolling stock maintenance systems. The cost of a locomotive as a traction unit ceases to be the determining factor. This is because the locomotive maintenance and repair cost for the entire period of its operation is much higher than the initial cost of the locomotive. The paper analyses the existing approaches to managing the cost of the life cycle of locomotives at the stages of selecting, updating, upgrading and operating the traction rolling stock. The necessity of improving the methods for assessing the degree of influence of reliability indicators of locomotive assemblies on the choice of the maintenance system and the cost of the locomotive life cycle is substantiated. Findings. It is proposed to use the concept of «the effect of dependent failures» when calculating the cost of locomotive renewal after unscheduled repairs and its life cycle cost. We improved the methods for determining the cost of unscheduled repairs, taking into account dependent failures and the coefficient of assessment of the effect of dependent node failure on the locomotive maintenance system. The proposed coefficient will determine the nodes, the failure of which affects the renewal cost more than their nominal value. It will also help to take into account the probable losses due to node failure during the development and adjustment of the locomotive maintenance system. Originality. For the first time, it is proposed to use the concept of the effect of de-pendent failures to calculate the locomotive renewal cost when performing unscheduled repairs, as well as the loco-motive life cycle cost. Practical value. The improved calculation method for determining the cost of unplanned repairs with account taken of dependent failures can be used to compare and evaluate different variants of the locomotive maintenance system and to develop the locomotive diagnostic systems.Item Consideration of Dependent Failures Impact on Selecting the System of Locomotive Maintenance(Kaunas Univ. of Technology, Palanga, Lithuania, 2019) Bodnar, Borys Ye.; Ochkasov, Oleksandr B.; Bodnar, Yevhen B.; Hryshechkina, Tatiana S.; Skvireckas, R.ENG: Modern measures aimed at reducing the operating costs are closely related to such concepts as LCC and RAMS-approach. The article analyzes the existing standards that regulate their usage. The purpose of the research is to improve the methodology for determining the renewal costs of locomotive nodes with due regard to dependent failures. To describe the propagation of dependent failures in the system, the authors propose to use the wave approach. The dependent failures impact on the system is determined on the basis of information about the relationship between elements and data from a technological-economic map concerning the cost of locomotive nodes renewal. To take into account the probabilistic nature, the authors propose to use the methods of expert research for determining the probability of failure of dependent elements. The authors proposed a method for determining the probability of the locomotive nodes breakdown considering the dependent failures. The method of calculating the average cost of unscheduled repair, considering the dependent failures of interrelated elements was improved. For the first time, a recurrence relation on a set is deduced, by which the volume of damage is calculated at the dependent failures of elements in a complex system. The coefficient, which will allow assessing the impact of dependent failures on the maintenance system and the life cycle cost of a locomotive, is proposed. On the basis of the proposed method, the calculations for the electric equipment of electric locomotives, DE1 series were made. A comparison of the renewal cost of electrical equipment with considering the dependent failures of related elements was made.Item Determination of Integrated Indicator for Analysis of the Traffic Safety Condition for Traction Rolling Stock(Kaunas University of Technology, Kaunas, Lithuania, 2018) Bodnar, Borys Ye.; Bolzhelarskyi, Yaroslav V.; Ochkasov, Oleksandr B.; Hryshechkina, Tatyana S.ENG: Traffic safety is a major priority in railway transport operation. Locomotive facility is one of the responsible units in general system of railways. A complex and cumbersome system of indicators is used in locomotive facilities to analyze the operation. The existing system makes it difficult to analyze the general level of work organization in the locomotive facilities. Purpose of the study is to determine the methodology of forming a certain dimensionless indicator (or group of indicators) that will reflect the general level of safety in the locomotive facilities. As the research methodology it was chosen principal component analysis as the corresponding mathematical apparatus, which makes it possible to analyze the existing indicators characterizing the performed work and the traffic safety condition with the necessary degree of informativity. As a result, the main components and the degree of their influence on the general level of traffic safety in the locomotive facilities are set. The indicators that have the most influence on the technical and safety components of the integrated indicator of traffic safety condition are determined. Originality of the work is that it for the first time proposes the concept of index of traffic safety condition and the method of its determination using the principal component analysis. Practical value of the work lies in the fact that the ranking of technical and safety components according to the degree of their influence on the general traffic safety index has been performed. Also, the locomotive units which have the greatest influence on the traffic safety condition and reliability were determined.Item Safety Performance Analysis of the Movement and Operation of Locomotives(Kaunas University of Technology; Publishing House “Technologija“, Kaunas, Lithuania, 2018) Bodnar, Borys Ye.; Ochkasov, Oleksandr B.; Bodnar, Yevhen B.; Hryshechkina, Tatiana S.; Keršys, RobertasENG: To estimate the state of the locomotive facility and work, performed by the locomotives, a system of planned and calculated indicators is used. The state of traffic safety in a locomotive facility is estimated in most cases by comparing the absolute number of traffic incidents with previous periods. Accordingly to the existing system of traffic safety analysis, the volume of work performed in the locomotive facility is not taken into account. The purpose of the research is to determine the methodology for forming a certain dimensionless indicator (or group of indicators) that will reflect the overall level of safety in the locomotive facility, taking into account the volumes of work performed by locomotives. The authors suggest the usage of the relative indicators to estimate the state of traffic safety, factoring in the volumes of transportation. As a method of research, we chose the method of the main components as the appropriate mathematical apparatus, which allows analysing the proposed indicators, characterizing the performed work and the traffic safety state with the necessary degree of informativeness. As a result, the most informative indicators and the degree of their correlation with the general index of traffic safety state were determined. Originality of the study lies in the fact that the system of indicators for the traffic safety analysis was improved; the concept of the traffic safety state index and the method of its determination using the method of the main components were improved. The practical value of the work is that we propose to use the relative indicators for estimating the traffic safety, taking into account the volumes of transportation; the ranking of the proposed indicators accordingly to the degree of their impact on the overall level of traffic safety is performed.Item Simulation of Locomotive Repair Organization by the Methods of Queue Systems Theory(Дніпропетровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2018) Bodnar, Borys Ye.; Ochkasov, Oleksandr B.; Bodnar, Yevhen B.; Hryshechkina, Tetiana S.; Ocheretnyuk, Maksym V.ENG: Purpose. The article is aimed to evaluate the influence of locomotives` operation and reliability indicators on the system of locomotives repair organization in depot, using the methods of queue theory. Methodology. The article describes the locomotive repair workshop using the terms and concepts of the queue systems theory (QST). The tasks solved during simulation of the repair workshop operation are formulated, the list of initial data and simulation results is given. A graphical simulation environment Simulink was used as a software simulation tool. Findings. It was established that the main indicators of locomotive depot operation are affected by the volume of traffic, the reliability of locomotives, the rule used to select locomotives from the queue, the number of operating repair bays. The developed model of the depot repair workshop will make possible rational planning of the repair workshop`s equipment use, the human capital, the time of putting the locomotives into repair taking into account the workshop loading uniformity, as well as to improve the repair parts supply logistics. This model in a simplified form describes the repair process of the main diesel locomotive fleet, and can be supplemented depending on the repair type performed in the depot. Originality. The paper presents the locomotive repair depot as an object of the queue systems theory. The simulation model of the locomotive repair depot was developed. It allows analyzing the influence of various factors on the system of locomotives` repair organization in the depot. Practical value. The obtained results make it possible to determine the influence of locomotives` operation and reliability indicators on the organization of the locomotive repair depot operation. In further studies, the developed model can be used to improve the system of repair organization on the railway network when introducing new series of locomotives and changing the strategy of their maintenance.