2019
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Item 1 (79) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item 2 (80) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item 3 (81) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item 4 (82) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item 5 (83) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item 6 (84) випуск. Наука та прогрес транспорту(Дніпровський національний університет залізничного транспорту ім. акад. В. Лазаряна, Дніпро, 2019)UK: У статтях наведені наукові дослідження, виконані авторами в Дніпропетровському національному університеті залізничного транспорту імені академіка В. Лазаряна та інших організаціях. Статті присвячені вирішенню актуальних питань залізничного транспорту по наступних напрямках: автоматизовані системи управління на транспорті, екологія на транспорті, експлуатація та ремонт засобів транспорту, матеріалознавство, залізнична колія, інформаційно-комунікаційні технології та математичне моделювання, нетрадиційні види транспорту, машини та механізми, транспортне будівництво, рухомий склад і тяга поїздів. Вісник становить інтерес для працівників науково-дослідних організацій, викладачів вищих навчальних закладів, докторантів, аспірантів, магістрантів та інженерно-технічних працівників.Item Analytical Determination of the Reduced Rotational Resistance Coefficient of the Construction Machine Slewing Gear(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Bondarenko, Leonid N.; Posmitiukha, Oleksandr P.; Hlavatskyi, Kazymyr Ts.EN: Purpose. Designing new models of construction machines is closely related to the development of slewing gear, and that, in turn, has a drive whose power and dimensions depend on the rotational resistance and the reduced fric-tion coefficient in the units. The absence of analytical dependencies for determining the reduced coefficient of friction for the rotation of construction machines, first, restricts the designer's ability to select materials, and secondly, does not allow the adoption of optimal design solutions. Therefore, the purpose of the article is to find analytical solutions to determine the rotational resistance in the slewing gear of construction machines, which allows project-ing more advanced gears and machines in general. Existing techniques are based on empirical dependencies and experimental coefficients that reduce the accuracy of calculations, increase the size and cost of work. It is proposed to improve the accuracy and simplify the process of determining the rotational resistance and the magnitude of the reduced rotational resistance coefficient of the building tower cranes. Methodology. The set objectives can be achieved by means of analytical dependencies for determination of rolling friction coefficients over linear and point contacts. This will enable to find the more accurate value of the resistance coefficient, and the constructor during the calculations to take targeted measures to reduce it, using the mechanical constants of materials of the units and their geometric parameters. The calculation is based on Hertz contact deformation theory and the body point plane mo-tion theory. Findings. The obtained dependencies will allow analytically to find the resistance of rolling resistance of rollers in construction machines with fixed and rotating pillars, with circular rotary devices, as well as in ball and roller slewing rings. The calculated values of the rotational resistance coefficients for some types of mechanisms give similar values with those recommended, while for others they significantly differ and require their refinement in reference values. Originality of the work consists in the use of analytical dependences for determining the reduced coefficient of the rotational resistance over linear and point contacts using Hertz contact deformation theory and Tabor partial analytic dependencies theory. Practical value. The obtained dependencies will allow to design new types of slewing gear units of the construction machines and to reveal the additional rotational resistances.Item Computer Modeling of Air Pollution in Case of Dust Cloud Movement in Open Pit Mine(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Berlov, Oleksandr V.; Gabrіnets, Volodymyr O.; Horiachkin, Vadym M.ENG: Purpose. Explosions in open pits lead to the formation of dust clouds. These clouds lead to intense air pollution. An important task is the development of methods for predicting the dynamics of atmospheric air pollution during ex-plosions in open pits. The purpose of this work is development of a numerical model to predict atmosphere pollution after explosion in open mine pit. The task is to develop a numerical model that would allow for the calculation to take into account the geometrical shape of the open pit mine, the parameters of the meteorological situation (wind speed, atmosphere), the shape of the dust cloud that is formed in the open pit mine at the site of the explosion. Methodology. Mathematical modeling of dust cloud dispersion during an explosion in an open pit mine is based on the use of fundamental equations of aerodynamics and mass transfer. The airflow velocity field in the open pit mine is modeled using the Laplace equation for the velocity potential. The formation of the concentration field of dust is mod-eled on the basis of the equation of convective-diffusion dispersion of an impurity. For numerical integration of model-ing equations, difference schemes are used. The Laplace equation for the velocity potential is numerically integrated using the Richardson method. For the numerical integration of the convective-diffusion dispersion equation for an im-purity, an implicit difference splitting scheme is used. Findings. A CFD model has been developed that allows you to calculate the formation of pollution zones during the movement of a dust cloud in the open pit mine. A feature of the developed model is the speed of calculation. For practical use of the developed model, standard input information is required. Originality. In contrast to the existing models in Ukraine, the developed numerical model allows taking into account the geometrical shape of the open pit mine and the geometrical shape of the dust cloud when making predictive calculations to assess the level of air pollution caused by explosions in open pits. Practical value. The developed nu-merical model can be implemented on computers of low and medium power. For practical use of the numerical model, standard information on meteorological conditions in open pit mine is required. The numerical model can be used for environmental assessment of the effect of explosions in open pit mine on environmental pollution and work areas.Item Computer Simulation of Dead-End Mine Working Ventilation(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Biliaieva, Viktoriia V.; Kirichenko, Pavlo S.; Gunko, Olena Y.; Bondarenko, Iryna O.; Mashykhina, Polina B.; Yakubovska, Zinaida M.ENG: Purpose. The important problem in the field of ecological safety and industrial safety is providing of normal microclimate in dead-end mine working. In these regions of the mine methane gas can be accumulated and as a result explosion may take place. So, to avoid these accidents it is important to ventilate appropriately dead-end mine working. The purpose of the work is development of quick computing mathematical model to obtain information about dead-end mine working ventilation process. Methodology. The process of dead-end mine working ventilation computing is separated in two stages. At the first stage the velocity flow field is computed in the dead-end mine working. We consider the situation when the suction tube is situated in this region. To solve this problem the fluid dynamics model of inviscid gas flow was used. At the second stage of the computational modeling the convective-diffusive equation of admixture transfer was used. The equation takes into account non-uniform flow field in the dead end mine workings. Findings. The developed numerical model was coded using FORTRAN language. The developed computer code allows to perform numerical experiment to assess the efficiency of suction tube imple-mentation to decrease methane gas concentration in dead-end mine working. Originality. The developed numerical model takes into account physical factors, which are not considered nowadays in the empirical models, which are used for solving the problems of dead-end mine working ventilation. It allows taking into account the geometrical form of the dead-end mine working. Practical value. The developed computer program allows to perform calculations to assess the efficiency of suction system used for the ventilation of the dead-end mine working.Item Determining Zones of Chemical Pollution in the Citiesand Assessment of Chronic Diseases Risks(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Biliaev, Mykola M; Rusakova, Tetiana I.EN: Purpose. The scientific paper is aimed at creating a methodology of chemical pollution zones in the territories of industrial cities and accounting the possibility of assessing the risks of chronic diseases. Methodology. The method of numerical calculation of nitrogen dioxide concentration in atmospheric air is based on the solution of three-dimensional impurity transfer equations, which directly comes from a permanently stationary source (industri-al enterprise) and a linearly distributed source (highway). The method takes into account the process of chemical transformation of impurities and photolysis in the atmosphere. The numerical model is based on the splitting of model equations and their solution using an implicit difference scheme. Findings. The created software allows con-ducting computational experiments to calculate the areas of atmospheric air pollution with nitrogen dioxide, taking into account the interaction of impurities coming from various types of pollution sources and meteorological para meters. On the basis of the obtained field of nitrogen dioxide concentration, an assessment of the change in the risk of chronic intoxication associated with atmospheric air pollution with nitrogen dioxide over 50 years was carried out. Originality. For the first time the regularities of changes in the level of atmospheric air pollution with nitrogen dioxide have been established with due regard to the mutual influence of emissions from the industrial enterprise and highway and their chemical transformation in the atmosphere. The risk of chronic intoxication has been calcu-lated and its changes have been analyzed with due regard to the interaction of emissions from the industrial enter-prise and highway, it leads up to 10% of risk increasing. Practical value. Authors developed a mathematical model and method of numerical calculation. Software created on their base allows obtaining quickly quantitative results necessary in developing the system for monitoring the man-made loaded regions of the city. The obtained patterns of impurities dispersion allow us to estimate the levels of pollution in urban areas of the city by emissions from in-dustrial enterprises and highways. Accounting of the mutual impact of emissions and the calculation of risks of in-toxication allows solving environmental problems arising in the development of transport strategy in cities.Item Impact of Cars with 25 TF/Axle Load on the Track Condition(Дніпровський національний університет залізничного транспорту ім. В. Лазаряна, Дніпро, 2019) Patlasov, Oleksandr M.; Fedorenko, Yelyzaveta M.EN: Purpose. The research is aimed at determining changes in the state of the geometrical parameters of the railway track, depending on the passing tonnage in dynamic interaction with the 25 tf/axle load rolling stock. Methodology. For data acquisition, the authors carried out a statistical analysis of the indicators of digital measure-ments of the track condition by KVL-P track-measuring cars. Using the program of calculating the meansquare deviation of the geometric parameters of the track, the deviation of the track parameters within the test sections was estimated. Findings. During the observation period it was found that on average the intensity of track strain accumulation increases. However, according to the results of the factor dispersion analysis with 0.95 probability, it is impossible to unequivocally state the impact of the factor of using the cars with an axial load of up to 25 tf/axle on the deterioration of the track condition parameters. Herewith it should be noted that the share of cargo carried in the cars with axial load of up to 25 tf/axle during the observation period was less than one per cent. According to the values of the meansquare deviation, the state of the geometrical parameters of the track and their predicted changes were estimated, which showed that the increased axial load will lead to decreased life of the rails, which are the most expensive elements of the track structure, shortened service life of the railroad switches and increased labor costs for workers involved in track repair and maintenance. The corresponding reduction of inter-repair periods, which corresponds to the standards, is projected. In order for heavy-duty wagons not to destroy the infrastructure, there must be at least two limitations: by the types of goods transported and by the speed of movement. Originality. The authors conducted a study to assess the impact of cars with 25 tf/axle load on the state of the geometric parameters of the railway track and proposed solutions to the issue of introducing the 25 tf/axle load rolling stock in Ukraine. Practical value. On the basis of the obtained results it is possible to estimate the impact of the axial load on the intensity of the track condition changes and to predict the reduction of inter-repair periods in connection with the track deterioration and in accordance with the train speed restriction.Item Influence of Loading from the Axle of a Gondola Car on its Dynamic Indicators and Railway Track(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Shvets, Anzhela O.; Bolotov, Oleksij O.EN: Purpose. Increasing the maximum loading from the car axle on the rails during transportation of goods and the speed of movement of railway vehicles will enhance the integration processes between the countries. In order to ensure safe and reliable traffic at the railways it is necessary to improve control, quantitative evaluation of the dy-namic loading of the rolling stock, which in the process of its operation is a relevant scientific and technical prob-lem. The purpose of this work is to study the influence of the axle loading increase in gondola cars, taking into ac-count the possible speed increase on their main dynamic indicators and indicators of interaction of rolling stock and track. Methodology. The study was carried out by the method of mathematical and computer simulation of the dy-namic loading of a gondola car using the model of spatial oscillations of the coupling of five cars and the software complex developed in the branch research laboratory of the dynamics and strength of rolling stock (BRL DSRS). The initial data for research are as follows: the movement of gondola car of the model 12-532 with typical bogies of 18-100 at the speeds ranging from 50 to 90 km/h in curves with radii of 350 and 600 m, with superelevation of 130 and 120 mm, respectively. Findings. The article analyzes the dynamic qualities of a rolling stock using the example of gondola cars, the calculations are performed using the package of applied programs with sufficient accuracy for practice. During the theoretical studies and simulation, taking into account the processes of freight car oscillation in case of increasing the axle loading, the dependences of the main dynamic parameters, taking into account the movement speed were obtained. Originality. Originality of the work results lies in the study of the influence of in-creasing the axle loading in gondola cars, taking into account the possible movement speed increase on the dynamic loading in order to solve the problem of forecasting the rolling stock dynamics. The results of theoretical studies, taking into account the movement speed in the curved track sections of small and medium radius were obtained for the first time. Practical value. The application of these results will contribute to improving the traffic safety of freight cars and will improve the technical and economic performance of railway transport.Item Intelligent Routing in the Network of Information and Telecommunication System of Railway Transport(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Pakhomova, Victoria M.; Skaballanovich, Tetiana I.; Bondareva, Valentyna S.ENG: Purpose. At the present stage, the strategy of informatization of railway transport of Ukraine envisages the tran-sition to a three-level management structure with the creation of a single information space, therefore one of the key tasks remains the organization of routing in the network of information and telecommunication system (ITS) of railway transport. In this regard, the purpose of the article is to develop a method for determining the routes in the network of information and telecommunication system of railway transport at the trunk level using neural network technology. Methodology. In order to determine the routes in the network of the information and telecommunica-tion system of railway transport, which at present is working based on the technologies of the Ethernet family, one should create a neural model 21-1-45-21, to the input of which an array of delays on routers is supplied; as a result vector – build tags of communication channels to the routes. Findings. The optimal variant is the neural network of configuration 21-1-45-21 with a sigmoid activation function in a hidden layer and a linear activation function in the resulting layer, which is trained according to the Levenberg-Marquardt algorithm. The most quickly the neural net-work is being trained in the samples of different lengths, it is less susceptible to retraining, reaches the value of the mean square error of 0.2, and in the control sample determines the optimal path with a probability of 0.9, while the length of the training sample of 100 examples is sufficient. Originality. There were constructed the dependencies of mean square error and training time (number of epochs) of the neural network on the number of hidden neurons ac-cording to different learning algorithms: Levenberg-Marquardt; Bayesian Regularization; Scaled Conjugate Gradi-ent on samples of different lengths. Practical value. The use of a multilayered neural model, to the entry of which the delay values of routers are supplied, will make it possible to determine the corresponding routes of transmission of control messages (minimum value graph) in the network of information and telecommunication system of railway transport at the trunk level in the real time.Item Investigation of the Influence of the Rolling Stock Dynamics on the Intensity of Using the Railway Track Elements(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Bondarenko, Iryna O.; Neduzha, Larysa O.ENG: Purpose. The main purpose of this work is to research deformability parameters of the railway track under various operating conditions as the initial data for the formation of forced oscillations of rolling stock and the trackform use intensity. Methodology. For the research, an original model of the trackform, described with using the basic concepts of the theory of elasticity and the propagation of elastic waves was developed. Findings. It has been established that the ratio between the intensity of work of elements and the trackform, as criteria for deformability, can be used as the estimated parameters of the functionally safe operation of the track. It can be the basis for the classification of critical track states under which it had to perform work to restore its working capacity in order to ensure the required level of efficiency of use construction during the service life. Originality. Trackform and parameters of the elements of the track superstructure and substructure can be described using the railway tracks deformability behaviour. In the future this conclusion will help to increase the efficiency of the dynamic properties of rolling stock when designing and maintain in readiness the infrastructure while in operation. Practical value. Changes in the regulatory framework of rail transport in recent years provide for the observance of its functional safety, therefore, the question of the need to assess the impact of rolling stock on the way to be regarded as a dynamic process with consideration to the deformability resistance track. This research provides a basis for record of the stiffness of deformation that allows creating the regulatory framework for the functional safety of the railway track in Ukraine.Item Justification of Criteria for Ropeways Energy Efficiency(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Raksha, Serhii V.; Kuropiatnyk, Oleksii S.; Krasnoshchok, Oleksandr L.ENG: Purpose. The article is aimed to form and justify the energy efficiency indicators of ropeways of traditional design and ropeways with self-propelled wagons based on the determination and comparison of their values. The substantiation of the energy efficiency criteria of ropeway wagons allows us to determine fully the direction of further research in the field of development of alternative transport mode. Methodology. To obtain initial data, the authors reviewed the world trends in the development of ropeway wagons, proposed analytical formulas for determining criteria for ropeways` energy efficiency used to compare traditional ropeways and ropeways with self-propelled wagons. Herewith, we took into account the influence of the loading degree and rated power on the electric motor efficiency. In order to take into account the energy dissipation in the haul rope through its elastic properties, the concept of the efficiency coefficient of the haul rope was introduced. Findings. The authors formed a methodology for calculating the efficiency of ropeways, developed formulas for determining energy efficiency. We assessed the influence of the ropeway characteristics on their calculated values; constructed dependence graphs of the self-propelled ropeway efficiency coefficient on the rated electric motor power and the efficiency coefficient on the ropeway drive loading, as well as compared general efficiency coefficients for ropeways with self-propelled wagons and for ropeways of traditional design. The results are based on the averaged values of the electric motors parameters at their different loads. Originality. The authors first proposed and justified the energy-efficiency criteria for ropeways that make it possible a comparative analysis of traditional ropeways and those with self-propelled wagons. We determined the dependence of these indicators on the ropeway parameters. Practical value. The results of the comparative analysis of traditional construction of ropeways and the ropeways with self-propelled wagons, based on the proposed energy efficiency indicators, can be used to substantiate the feasibility of using certain type of rope-ways for the implementation of individual transport processes. The construction diagram of a self-propelled wagon can be used in the development of energy efficient passenger ropeway projectsItem Minimization of the Chemical Pollution Level at the Working Zones in Open Areas Using Screens(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Shynkarenko, Viktor I.ENG: Purpose. The scientific work aims to develop a new method for assessing the level of chemical air pollution in working zones located in open areas near highways using screens of different heights. Methodology. The analytical method for calculating the airflow velocity field near protective screens is based on the mathematical apparatus of the theory of complex variable functions, which allows obtaining the value of the velocity potential and the flow function, to calculate the velocity value at any point of the plane with a screen of different height. The obtained velocity field is used to calculate the level of carbon monoxide concentration in the numerical solution of the two-dimensional mass transfer equation. Findings. The developed program of numerical calculation allows conducting computational experiments on the effectiveness of the use of protective screens, taking into account changes in their geometry and meteorological conditions. The developed method based on the obtained concentration field makes it possible to carry out an assessment of the risk of chronic intoxication for the employees of the take-out trade, who are within the zone of the emission source (highway) for a long time. Originality. The regularities of changes in the concentration of carbon monoxide are established depending on the distance to the emission source at a height of 2 m from the ground in the presence of a screen of a certain height and in its absence. A risk assessment of chronic carbon monoxide intoxication has been carried out for take-out trade workers near the highway. It is shown that the presence of the screen reduces the risk of chronic CO intoxication by 10% as compared to its absence. Increasing the screen height to 1.8 m reduces the risk of chronic intoxication by 6% relatively to the situation when the screen height is 1.2 m. Practical value. The developed numerical-analytical method for calculating the level of chemical pollution in working zones in open areas and the program «Screen» created on its basis allow us to carry out a prompt forecast of atmospheric air pollution level with carbon monoxide taking into account the effectiveness of the screens. Quantitative results are necessary at the planning stage of trading places near highways, during the architectural-planned reorganization of adjacent developments.Item Modeling the Optimization Process of Investments in Development of the Enterprise Taking Into Account Random Costs(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Gasanov, Z. M.EN: Purpose. The study aims at substantiating the method to determine the optimal volume of investments for improving basic economic indicators of the enterprise’s performance selected by the company management at random costs at each stage of its development. Methodology. The proposed methodology for determining the optimal investment volume is based on simulation modeling methods and optimal control theory, in particular, the dynamic programming procedure, since the controlled process of the enterprise`s development is a multi-step one. Using step-by-step planning with generation of costs for transitions and statistical processing of results, a solution to optimization problem was obtained, to which the methods of mathematical analysis cannot be applied. Findings. An algorithm has been developed for calculating the minimal volume of capital investments for improving selected economic indicators and constructing the optimal trajectory for the enterprise`s development from the initial economic state to the final desired state. This takes into account unforeseen intermediate costs in the process of enterprise development. Originality. It is shown that using the methods of the theory of optimal control and simulation modeling, it is possible to calculate the minimal amount of capital investments to improve the selected economic indicators that determine the efficiency of the enterprise performance, taking into account the random costs of intermediate transitions by the development stages. Such calculation does not depend on the specific content of economic indicators. Practical value. The proposed methodology for calculating the minimal volume of capital investments is quite simple, but at the same time it allows, on the one hand, determining the priority areas of the enterprise’s investment activities. On the other hand, it increases the manageability and transparency of the enterprise’s economic activity, and increases the manager’s confidence in the correctness of the decisions made.Item Numerical Modeling of Air Pollution From Dumps(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Biliaiev, Mykola M.; Rusakova, Tetiana I.; Kalashnikov, I. V.; Bondarenko, Iryna O.; Gunko, Elena Yu.ENG: Purpose. Rock dumps are long-term sources of air pollution. A significant amount of harmful substances enters the atmosphere. Particularly intense is the pollution of atmospheric air due to dusting dumps. An important task is the development of methods for predicting the dynamics of atmospheric air pollution during the emission of harmful impurities from dumps. When developing methods for predicting the dynamics of air pollution from dumps. It is very important to create a universal model that would allow on a single computing platform to calculate the process of atmospheric air pollution for various impurities that are released from dumps. Another important problem is the choice of the place for optimal placement of future dumps in order to minimize their negative impact on the environment. Methodology. Numerical modeling of the formation of atmospheric pollution zones near rock dumps is based on the application of the equation of turbulent dispersion of an impurity in the atmosphere. To solve the problem of choosing the rational location of the dumps, the conjugate equation is used. Numerical integration is carried out using an implicit difference scheme. Findings. Numerical models are developed. The first numerical model allows one to evaluate the effect of rock dumps on air pollution. The second numerical model allows, on the basis of a one-time calculation, to determine the rational location of the future dump from the point of view of its minimal impact on air pollution. Originality. Two numerical models are proposed that are based on the application of the turbulent diffusion equation and the conjugate equation. These models make it possible to quickly determine the effect of rock dumps on air pollution. The models take into account the convective transport of the pollutant, atmospheric turbulent diffusion, the intensity of the emission of impurities from the dump. Practical value. The developed numerical models are implemented in the form of program codes. These program codes can be used when performing serial calculations on computers of low and medium power, i.e. computer technology, which is available to organizations involved in environmental issues in technologically saturated regions. When carrying out calculations based on the constructed numerical models, typical initial data are used regarding the intensity of the emission of impurities from dumps, weather conditions characteristic of a specific region of the country.Item Optimal Route Definition in the Railway Information Network Using Neural-Fuzzy Models(Dnipro National University of Railway Transport named after Academician V. Lazaryan, 2019) Pakhomova, Victoria M.; Mandybura, Y. S.ENG: Purpose. Modern algorithms for choosing the shortest route, for example, the Bellman-Ford and Dijkstra algo-rithms, which are currently widely used in existing routing protocols (RIP, OSPF), do not always lead to an effective result. Therefore, there is a need to study the possibility of organizing routing in in the railway network of infor-mation and telecommunication system (ITS) using the methods of artificial intelligence. Methodology. On the basis of the simulation model created in the OPNET modeling system a fragment of the ITS railway network was considered and the following samples were formed: training, testing, and control one. For modeling a neural-fuzzy network (hybrid system) in the the MatLAB system the following parameters are input: packet length (three term sets), traffic intensity (five term sets), and the number of intermediate routers that make up the route (four term sets). As the resulting characteristic, the time spent by the packet in the routers along its route in the ITS network (four term sets) was taken. On the basis of a certain time of packet residence in the routers and queue delays on the routers making up different paths (with the same number of the routers) the optimal route was determined. Findings. For the railway ITS fragment under consideration, a forecast was made of the packet residence time in the routers along its route based on the neural-fuzzy network created in the MatLAB system. The authors conducted the study of the average error of the neural-fuzzy network`s training with various membership functions and according to the differ-ent methods of training optimization. It was found that the smallest value of the average learning error is provided by the neuro-fuzzy network configuration 3–12–60–60–1 when using the symmetric Gaussian membership function according to the hybrid optimization method. Originality. According to the RIP and OSPF scenarios, the following characteristics were obtained on the simulation model created in the OPNET simulation system: average server load, average packet processing time by the router, average waiting time for packets in the queue, average number of lost packets, and network convergence time. It was determined that the best results are achieved by the simulation net-work model according to the OSPF scenario. The proposed integrated routing system in the ITS network of railway transport, which is based on the neural-fuzzy networks created, determines the optimal route in the network faster than the existing OSPF routing protocol. Practical value. An integrated routing system in the ITS system of railway transport will make it possible to determine the optimal route in the network with the same number of the routers that make up the packet path in real time.Item Outlooks of Using DBN B.2.6-161:2017 «Wooden Structures» in Design Practice(Дніпровський національний університет залізничного транспорту імені академіка В. Лазаряна, Дніпро, 2019) Bannikov, Dmytro O.EN: Purpose. From 01.02.2018, the new state standards DBN B.2.6-161:2017 were introduced into the wooden structures design practice. They replace the recently prepared codes DBN B.2.6-161:2010, which, in turn, were elaborated to replace the SNiP II-25-80. The author of this publication would like to draw the attention of develop-ers and potential users of the codes DBN B.2.6-161:2017 to the points that are not entirely clear, which at first read-ing caused him certain difficulties in terms of their practical use. Methodology. The practical experience accumu-lated by the author in the use of normative literature in educational practice, as well as the available experience dur-ing laboratory studies with students, made it possible to estimate the recently introduced codes DBN B.2.6-161:2017 from a practical point of view. Findings. In general, the new codes, recently introduced into design practice, are progressive both in their content and in terms of their use in construction practice. However, the existing problem areas in these standards, which are considered in this publication, in our opinion, can significantly limit the possibil-ity of their wide practical application. Originality. The analysis of recently introduced new standard was carried out by the author of the publication not only in terms of assessing quality requirements and recommendations, but also in terms of the quantitative aspect of the issue. Practical value. The author’s experience in calculating simple ele-ments and basic types of connections according to the new codes DBN B.2.6-161:2017 indicates that the bearing capacity determined for various cases is lower on average by 1.5 – 3 times than according to the previous codes SNiP II-25-80. From a practical point of view, this revealed discrepancy means that the already constructed struc-tures may require some reinforcement or reconstruction, and new designed structures should have large bearing sec-tions of the elements and, accordingly, large bearing capacity and weight.
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