bluuebunny/crossref_metadata_2025 huggingface dataset:
Increasing of founding properties of secondary aluminium alloys
Authors: Lyutova O. V.
Published: April 2015

Purpose. To study the influence of metallurgical factors of production on casting properties of secondary aluminum alloy АК9М2. Methodology. For the experimental melts shaving amount in a charge, iron content and the quantity of modifier additive were chosen as independent variables. The components of modifier were being changed in the intervals of 25…40 % Na2CO3, 12…20 % SiC, 3…8 % Ti, the other – S. The microstructure of alloys was investigated under a light microscope, using the method of quantitative metallography. Influence analysis of certain parameters of alloys was conducted by mathematical statistics methods. The influence of shaving additions, iron and modifier amount on liquidity and porosity of the resulting alloys was studied. Findings. The paper shows that the increase of shaving content in the charge from 1 to 19 % and iron content in alloy from 0.66 to 2.34 % resulted in the decline of alloy liquidity on 30…35 %. Simultaneously the linear shrinkage reduction for 18…20 % and the porosity increase from 0.5 to 2.5 points were observed. The presented changes of alloy casting properties are conditioned by the amount of intermetallic phases of unfavorable form and its capacity for aeration. Increase of modifier additive from 0.02 to 0.15 % resulted in the liquidity increase on 10…15 %, the increase of linear shrinkage on 30…35 % and porosity decline from 2.5 to 0.5 points. At the same time a change of form of intermetallic phases and increase of their evenness were observed. Originality. The increase of iron concentration in silumin composition is accompanied by the decline of its liquidity. Thus, the rate of decline of alloy liquidity is proportional to the amount of dissolved iron. The character of iron influence is caused by formation of high temperature intermetallic compounds of the type Al3Fe, Al5SiFe, which promote the metal viscidity. Practical value. Practical use of the obtained scientific results would develop the technical solutions oriented to the quality indicator increase of silumin alloy.
Synthesis of optimal digital controller of flocculant dosing
Authors: Pismenskiy A. V.
Published: April 2015

Purpose. The task of automatic process control of the slime water thickening and flotation tailings clarification is the stabilization of thicken product density within the given range and keeping up the solids content in the overflow not above the permissible level with minimum use of the flocculants. In existing systems for automatic control the flocculant dosing is carried out according to the solids content in the device input (the principle of open-loop control). This leads to the excess consumption of the flocculants and increase the dispersion density of the overflow. To perform the synthesis of the optimal digital controller in order to minimize the deviations from the master control and ensure the specified quality of the transition process. Over controlling value should not exceed 5 %. To perform the system operation modeling in order to determine the quality of transient processes. Methodology. Synthesis of the optimal digital controller is based on the method of dynamic programming. Findings. A mathematical model of the object control is represented in the normal form of Cauchy and further in the form of differential equations. The optimum period of quantization as the function from specified error of control and the output coordinate change is calculated. The differential equation of Bellman is obtained and the condition for minimization of the quality functional. Bellman function is represented as a quadratic form from the variables of the system condition. In order to limit possible control, the weight coefficients of the functional are calculated based on maximum permitted values of the system condition variables and the control actions during the transient process. Practical value. Using the modeling of ACS of the flocculant dosing it was established that the over controlling amount is 3.5%, the transient process life 5.6 sec, the transient process is aperiodical, non-static control, which meets the requirements imposed on the ACS.
To the question of modeling of wheels and rails wear processes
Authors: Manashkin L. A. , Myamlin S. V.
Published: April 2015

Purpose. There is a need of wear process modeling in the wheel-rail system. This is related to the fact that the wear processes in this system are absolutely different in the initial and final stages. The profile change of rail and, especially, of the wheels caused by the wear significantly affects the rolling stock dynamics, traffic safety and the resource of the wheels and rails. Wear modeling and the traffic safety evaluation requires the accounting of the low frequency component forces (including the modeling of transitional areas) affecting the wheel on the side of the rail and carriage in motion of rolling stock, so the statistical analysis is not possible. Methodology. The method of mathematical modeling of the wheel set and the rail interaction was used during the research conducting. Findings. As a result of the modeling of the wheel set motion on the rail track, the mathematic model with 19 freedom degrees was obtained. This model takes into account the axle torque and studies wheels constructions as the components of the mechanical systems, consisting of a hub and tire. Originality. The mathematic model allows evaluating the wear degree of the wheels and rails when using on the rolling stock not only all-metal wheel sets, but also compound ones with the use of spring wheels and independent rotation of semi-axes with the wheels. Practical value. The development of the improved mathematical model of freight car wheel set motion with differential rotation of the wheels and compound axles allows studying the wear processes of wheels and rails.
Investigation of transient processes in tonal track circuits
Authors: Honcharov K. V.
Published: April 2015

Purpose.The purpose of investigation is the search for new analysis methods of tonal track circuits, the definition of signal waveform at the track receiver input. Methodology. The method of frequency characteristics was used for investigation of transient processes. Signal spectrum at the output of track generator was determined using fast Fourier transform. Signal spectrum at the input of track receiver was calculated after determining complex frequency characteristic of the tonal track circuit. To carry out such calculations the frequency characteristics of rail line parameters have been obtained resulting interpolation of reference data and the frequency characteristic of track receiver impedance has been calculated. To determine the signal time dependence at the input of track receiver the inverse fast Fourier transform was applied.Findings. The causes of signal distortion in the tonal track circuits have been clarified.Track filter and input filter of track receiver restrict upper and lower sidebands of the signal spectrum, which leads to prolonging the rise and fall of signal pulses.The rail line, cable lines, and the devices for protection and alignment do not affect the shape of signal pulses, and change only their amplitude. At influence of rise and fall of signal pulses in the connected RLC circuits of receiver arise free oscillations at the resonance frequencies. As a result of the interference of these oscillations occur beats and appears additional pulse. Originality. The method for the analysis of tonal track circuits has been improved that allows determining not only the level but also the time dependence of signal at the track receiver for any input action. Practical value. Obtained time dependence of signal at the track receiver input will be useful in the development of the new more perfect methods for determining the state of tonal track circuit. Proposed method of track circuit analysis may be used to search for new more informative form of signal current.
Problems of locomotive wheel wear in fleet replacement
Authors: Vaychunas G. , Gelumbitskas G. , Lingaytis L. P.
Published: April 2015

Purpose. To conduct a research and find out the causes of defects appearing on the wheel thread of freight locomotives 2М62 and SIEMENS ER20CF. Methodology. To find the ways to solve this problem comparing the locomotive designs and their operating conditions. Findings. After examining the nature of the wheel wear the main difference was found: in locomotives of the 2M62 line wears the wheel flange, and in the locomotives SIEMENS ER20CF – the tread surface. After installation on the 2M62 locomotive the lubrication system of flanges their wear rate significantly decreased. On the new freight locomotives SIEMENS ER20CF the flange lubrication systems of the wheel set have been already installed at the factory, however the wheel thread is wearing. As for locomotives 2M62, and on locomotives SIEMENS ER20CF most wear profile skating wheels of the first wheel set. On both locomotive lines the 2М62 and the SIEMENS ER20CF the tread profile of the first wheel set most of all is subject to the wear. After reaching the 170 000 km run, the tread surface of some wheels begins to crumble. There was a suspicion that the reason for crumb formation of the wheel surface may be insufficient or excessive wheel hardness or its chemical composition. In order to confirm or deny this suspicion the following studies were conducted: the examination of the rim surface, the study of the wheel metal hardness and the document analysis of the wheel production and their comparison with the results of wheel hardness measurement. Practical value. The technical condition of locomotives is one of the bases of safety and reliability of the rolling stock. The reduction of the wheel wear significantly reduces the operating costs of railway transport. After study completion it was found that there was no evidence to suggest that the ratio of the wheel-rail hardness could be the cause of the wheel surface crumbling.
Object-oriented model of railway stations operation
Authors: Kozachenko D. M.
Published: April 2015

Purpose. The purpose of this article is improvement of the railway stations functional model; it leads to time expenditure cut for formalization technological processes of their work through the use of standard elements of technology. Methodology. Some technological operations, executives and technology objects are considered as main elements of the railway station functioning. Queuing techniques were used as the methods of research, simulation, finite state machines and object-oriented analysis. Findings. Formal data structures were developed as the result of research that can allow simulating the operation of the railway station with any degree of detail. In accordance with the principles of object-oriented approach in the developed model, separate elements of station technology are presented jointly with a description of their behavior. The proposed model is implemented as a software package. Originality. Functional model of railway stations was improved through the application of object-oriented approach to data management. It allow to create libraries of elementary technological processes and reduce time expenditure for formalization the technology of stations work. Practical value. Using of software package that it was developed on the base of proposed model will reduce time expenditure of technologists in order to obtain technical and operational assessment of projected and existing rail stations.
Dynamic running test results of diesel train 630M of production A.S. PESA (Poland)
Authors: Blohin E. P. , Granovskiy R. B. , Dzichkovskiy E. M. , Krivchikov A. E. , Granovskaya N. I. , Tsiyupa A.
Published: April 2015

Purpose. Experimental definition of values of the dynamic parameters characterizing traffic safety of the rail autobus in tangent and curved track sections and switches, and conformity check to their demands of normative documents. Methodology. Test methods are based on comparison of experimentally determined dynamic qualities of the autobus with their admitted values. As the parameters defining traffic safety, the numerical value of which is resulted further, are used the following ones: the derailment stability coefficient; vertical dynamics coefficients in the first and second steps of spring suspension; the frame forces; smoothness of movement. Determination of the derailment stability coefficient is performed by a known technique. Vertical dynamics coefficients in the each step of spring suspension are defined as the relation of dynamic vertical bending flexures to magnitudes of their static values corresponding to the set occupancy of the autobus. Findings. Coefficient values of the vertical dynamics of train carriages in the first and second steps of spring suspension, as well as the value of frame forces and parameters of movement smoothness did not exceed the admissible standard values, and was higher than the minimum admissible value. Originality. Values of the parameters characterizing dynamic qualities of new type of the rail autobus are obtained, and possibility of its operation on the main ways of the railways of Ukraine is shown. Practical value. Admissible speeds of the rail autobus traffic on various railway track sections are defined.
Electric pulse treatment of welded joint of aluminum alloy
Authors: Vakulenko I. A. , Nadezhdin Yu. L. , Sokirko V. A. , Volchok I. P. , Mitiaev A. A.
Published: April 2015

Purpose. Explanation of the redistribution effect of residual strengthes after electric pulse treatment of ark welding seam of the aluminum alloy. Methodology. Alloy on the basis of aluminium of АК8М3 type served as the research material. As a result of mechanical treatment of the ingots after alloy crystallization the plates with 10 mm thickness were obtained. After edge preparation the elements, which are being connected were butt welded using the technology of semiautomatic argon arc welding by the electrode with a diameter of 3 mm of AK-5 alloy. Metal structure of the welded joint was examined under the light microscope at a magnification of 200 and under the scanning electronic microscope «JSM-6360 LA». The Rockwell hardness (HRF) was used as a strength characteristic of alloy. Hardness measuring of the phase constituents (microhardness) was carried out using the device PМТ-3, with the indenter loadings 5 and 10 g. The crystalline structure parameters of alloy (dislocation density, second kind of the crystalline grid distortion and the scale of coherent scattering regions) were determined using the methods of X-ray structural analysis. Electric pulse treatment (ET) was carried out on the special equipment in the conditions of the DS enterprise using two modes A and В. Findings. On the basis of researches the previously obtained microhardness redistribution effect in the area of welded connection after ET was confirmed. As a result of use of the indicated treatment it was determined not only the reduction of microhardness gradient but also the simultaneous hardening effect in the certain thermal affected areas near the welding seam. During study of chemical composition of phase constituents it was discovered, that the structural changes of alloy as a result of ET first of all are caused by the redistribution of chemical elements, which form the connections themselves. By the nature of the influence the indicated treatment can be comparable with the thermal softening technologies of metallic materials. Originality. The observed structural changes of alloy and related to them microhardness change in the areas near the welding seam after ET are conditioned by both the change of morphology of structural constituents and the redistribution of chemical elements. In case of invariability of chemical elements correlation in the phase constituents of alloy the reduction effect of gradient microhardness should be far less. Practical value. In practice, the negative effect of the wares embrittlement made using the casting technologies, excluding the pressure casting and quite difficult selection of chemical composition of alloy can be significantly reduced during the treatment of alloy with electric pulses.
Modified network simulation model with token method of bus access
Authors: Pakhomova V. N. , Stribulevich L. V.
Published: April 2015

Purpose. To study the characteristics of the local network with the marker method of access to the bus its modified simulation model was developed. Methodology. Defining characteristics of the network is carried out on the developed simulation model, which is based on the state diagram-layer network station with the mechanism of processing priorities, both in steady state and in the performance of control procedures: the initiation of a logical ring, the entrance and exit of the station network with a logical ring. Findings. A simulation model, on the basis of which can be obtained the dependencies of the application the maximum waiting time in the queue for different classes of access, and the reaction time usable bandwidth on the data rate, the number of network stations, the generation rate applications, the number of frames transmitted per token holding time, frame length was developed. Originality. The technique of network simulation reflecting its work in the steady condition and during the control procedures, the mechanism of priority ranking and handling was proposed. Practical value. Defining network characteristics in the real-time systems on railway transport based on the developed simulation model.
Use efficiency of dynamic stabilizer in the post-repair period of railways in Ukraine
Authors: Chernyshova O. S. , Umanov M. I. , Kovalev V. V. , Markov Y. S. , Gubar O. V.
Published: April 2015

Purpose. To analyze the interaction forces of the track and rolling stock at application of dynamic stabilizers, as well as the determination of the area, on which the track stabilization is necessary not only according to the technical indices but also according to the economic ones. Methodology.To achieve the research purpose the methods of analysis of material flows, peculiar to the places that need applications of dynamic stabilizers on railway transport tracks are used. Findings. Researches of relatively economic efficiency of dynamic stabilizers application, which were conducted by scientists during the last years, do not spread to comparison of cost of works on the track stabilizing and losses of railway for period of running. During the running period the trains move with a limited speed that causes corresponding financial losses. Speed limitation result in the both the motion time increase and in some occasions in the heavy consumption of fuel and energy resources. The more intensive track discord and expenses increase for its maintenance are observed in the sections of braking and acceleration immediately in front of and after the areas of limitation. The methodology relative to the estimation of economic efficiency of dynamic stabilizers application after completion of track repairs for the areas of Ukrainian railways with different operational conditions was developed. This methodology includes the losses calculation of railroad, which are predefined by extra motion time, heavy consumption of fuel and energy resources and charges for current maintenance. Originality. The methodology of cost effectiveness evaluating of the dynamic stabilizers application in the post-repair period was developed. Such an approach would allow one to take the rational decisions taking into account the features of the track sections, which were reconstructed. Practical value. The obtained results will rationally assign the works on the dynamic track alignment accounting the operational characteristics of the railway sections and the economic feasibility of the planned works completion.
Estimation of external factors influence on the organizational and resource support of engineering
Authors: Gusak Yu. V.
Published: April 2015

Purpose. The engineering industry is characterized by deep specialization and high co-operation, which suggests a high degree of interaction with other industries and the economy, highly sensitive to external factors. Effective regulation of the engineering industry’s organizational-resource support will ensure coherence of all the subsystems of the market economy, the competitive environment, a full course of the investment process and the success of the industry. Therefore there is a need for detailed estimation and analysis of the external factors’ influence on the formation and implementation indexes of the engineering industry’s organizational-resource support. Methodology. To establish the close connection between the set of external factors of formation and implementation indexes of the engineering industry organizational-resource support the correlation analysis was used, to calculate the amount of the formation and implementation indexes of the engineering industry organizational-resource support’s change under the influence of the external factors with malleability coefficient were applied. Findings. The external influence factors on the engineering industry organizational-resource support by the source of origin: industrial, economical, political, informational, and social were separated and grouped. The classification of the external factors influence on the engineering industry organizational-resource support, depending on their influence’s direction on the formation and implementation indexes of the engineering industry’s organizational-resource support was made. The connection closeness and the amount of the formation and implementation indexes of the engineering industry organizational-resource support change (the machinery index of and the sales volume machinery index) under the influence of the external factors with malleability coefficient were determined. Originality. The estimation of the external factors influence on the formation and implementation indexes of the engineering industry’s organizationalresource support was improved, which allows identifying the most influenced external factors and the amount of the formation’s and implementation’s indexes of the engineering industry’s organizational-resource support’s change. Practical value. The estimation of the external factors influence on the formation and implementation indexes of the engineering industry’s organizational-resource support allows detecting, developing and adjusting the necessary and effective levers of government regulation.
Basic principles of transport tourism development in Ukraine
Authors: Martsenyuk L. V.
Published: April 2015

Purpose. Undeveloped infrastructure and the system of public and tourist transport services prevent boom and spread of tourism glory of the country. Therefore, the development of tourist infrastructure and transport communication routes is a priority task. Methodology. Article methodology is based on the use of consequent methodological technique. Findings. Author analyzed the situation of tourism industry in Ukraine, set the basic principles for the tourism development and its priorities. The article contains the author's point of view on the fact that the tourism industry is of paramount importance to the state economics, and the development of this sector of public life should be a priority task for the near future. Originality. According to the author, the development of the inbound tourism is more reasonable, because it provides additional workplaces and exchange earnings. The author insists that the raise of quality level of domestic tourist services to the European standards would accelerate the development of Ukrainian tourism and would attract more holidaymakers from Ukraine and neighbouring countries. Practical value. The rational measures, which were taken regarding the proposed directions for the tourism development, can improve competitiveness of the Ukrainian tourist industry on the European tourist market.
Operational distribution of the train traffic volume on the sections of railway operating domain
Authors: Mozolevich G. Ya.
Published: April 2015

Purpose. The task of the operational distribution of train traffic volume on the sections of operating domain is the optimization one. It is solved in the operational conditions by the dispatch station. The article sets the problem of formalizing and finding the new ways to solve this urgent problem. Methodology. A new approach to solving the problem of operational distribution of train traffic volume on the sections of the rail network with a choice of routes for all train traffics was proposed. Findings. A study of possible routes for the train traffic handle on the operating domain used for mass freight transportations between Krivyi Rih and Donbas was carried out. The use of the proposed method allowed us to obtain a rational distribution of trains on the rail network sections. Originality. The method of train traffic volume distribution in the network under operational conditions was improved. The method, as opposed to the current one allows one to select the route of separate units handle (according to the criteria of the weighted average cost for 1 ton of cargo). Practical value. The use of the proposed technology of the operational distribution of train traffic volume will increase the efficiency of the railways in general and ensure the competitiveness of rail transportations. The methodology implementation involves the use of railway dispatch station for the automated workplaces with appropriate informational support.
The investigation of influence of laser radiation on the structure and mechanical properties of composite electrolytic nickel coating
Authors: Zabludovsky V. A. , Dudkina V. V. , Shtapenko E. Ph.
Published: April 2015

Purpose. Investigation of laser radiation effect on the structure and mechanical properties of electrodeposited nickel composite coatings containing ultrafine diamonds. Methodology. Electrodeposition of nickel films was carried out with the addition of a standard solution of ultrafine diamonds (UFD) on laser-electrolytic installation, built on the basis of the gas-discharge CO2 laser. Mechanical testing the durability of coatings were performed on a machine with reciprocating samples in conditions of dry friction against steel. The spectral microanalysis of the elemental composition of the film - substrate was performed on REMMA-102-02. Findings. Research of nickel coatings and modified ultrafine diamond electrodeposited under external stimulation laser demonstrated the dependence of the structure and mechanical properties of composite electrolytic coating (CEC), and the qualitative and quantitative distribution of nanodiamond coprecipitated from an electrodeposition method. Originality. The effect of laser light on the process of co-precipitation of the UFD, which increases the micro-hardness and wear resistance of electrolytic nickel coatings was determined. Practical value. The test method of laser-stimulated composite electrolytic nickel electrodeposition coating is an effective method of local increase in wear resistance of metal coatings, which provides durability save performance (functional) properties of the surface.
Development of coordination abilities of special medical groups students in physical education process
Authors: Dotsenko E. N.
Published: April 2015

Purpose. To analyze the problem of motor abilities development and health of students of special medical group in the process of physical education in technical universities. Determine the major factors, characteristics, and the relationship of physical development, physical fitness and coordination abilities of female students in special medical group. Establish regularities in precise movements mastering of different coordination structure and develop model characteristics of the relationship of coordination abilities and motor characteristics of students in special medical group. To substantiate and verify efficiency of coordination abilities development method of female students with regard to their functional status in the course of physical education in higher school. Methodology. Theoretical and methodological argument, characteristic of the experimental program in physical education teaching process of students in special medical group was shown. Findings. Research is to develop the training content in special medical groups with the use of coordinating elements and exercises to enhance the motor abilities of female students. Their influence on the level of physical development, functional training, as well as regularities in mastering and movement control of different coordinating structure at the female students of special medical group was studied. The comparative characteristic of female students athletic ability in the dynamics of the educational process, differentiated into groups according to nosology was presented. The criterion of spare capacities upgrade of the motor system in controlling the movements of different coordination structure was determined. Originality. The method of coordination abilities development of female students in special medical group, that aims on the formation and correction of motor control system of different coordination structure, a sense of body position and its individual parts in space, improving kinesthesia was introduced for the first time. The effect of the experimental program to the level of development and the relationship of coordination abilities and criteria of spare capacities in exact motions system control were determined. Practical value. To develop the content of training in special medical groups using the coordination exercises and elements to enhance the motor abilities of female students. Organizational and methodological aspects of holding trainings in special medical group with a load for students with different variations in health status were improved. The mathematical model describing the movements, including coordi nating students abilities in special medical group was developed. On the basis of developed indicators one can take into account the functional and physical fitness of students and form optimal regimes of motor activity for each nosologic group. It is especially important for the organization of educational process in universities physical education.
Definition of locomotive traction force with regard to uneven loading of wheel-motor block
Authors: Bodnar B. Ye. , Kapitsa M. I. , Kyslyi D. N.
Published: April 2015

Purpose. The article describes the most common methods for determining the locomotive traction force. Solving the tasks of traction calculations involves determination of the forces influencing the train at every point of the way. When choosing a rational trajectory of the train motion and the development of operational regulations of train driving it is necessary to determine the actual value of the locomotive traction force. Considering various factors, power value of traction electric motor of locomotive may have significant differences. Advancement of the operational definition system of the locomotive traction force during the calculations by electrical parameters of traction electric motor with regard to uneven load of wheel-motor block is the purpose of the article. Methodology. The method of determining the traction force of locomotives and diesel locomotives with electric transmission, which is based on primary data acquisition of traction electric engines of direct current behavior, was proposed. Sensors and their integration into the electrical circuitry of the locomotive in order to get the data in digital form and for operational calculation of the each traction motor mode and the definition of locomotive traction force are presented. Findings. The experimental investigation of the system of locomotive traction force determination with the electric traction motor ED-105 was offered. A comparison of electrical and mechanical power of the electric motor was conducted. Originality. The system of locomotives power operational definition, which takes into account the variable electro-mechanical factors of wheel and motor blocks and increases the accuracy of the calculations, was proposed. Practical value. The system is a part of an onboard complex in definition of energy-efficient regimes for trains movement and provides the definition of accelerating and decelerating forces.
Increasing of wear resistance of the graphitized steel
Authors: Akimov I. V.
Published: April 2015

Purpose. Graphitized steels are alloys, in which carbon is partly in form of graphite inclusions. Due to this such steels possess good antifriction properties, wear resistance, heat conductivity and a variety of other mechanical properties, which decently distinguish them from cast irons. However, such steels are not studied enough and practically are not used in mechanical engineering. Purpose of the work is the research of the possibility of wear resistance increase for graphitized steels in the conditions of metal-to-metal dry friction sliding to use them in the railway systems. Methodology. Graphitized hypoeutectoid, eutectoid and hypereutectoid steels have been used as a research material. Experimental alloys have been studied in the condition after thermal hardening. Hardness of alloys has been determined by the Vickers method. Wear resistance of steels has been studied in the conditions of metal-to-metal dry friction sliding with the use of МI-1 friction machine (disk to disk). Findings. Data, which allow assessing the wear resistance of experimental graphitized steels depending on carbon, silicon and copper content have been obtained in this work. The regression dependence obtained as a result of statistical processing of the experimental data allowed determining an optimal chemical content of the steel, which is characterized by high wear resistance. Originality. A dependence describing carbon, silicon and copper content on the specimen's weight loss during metal-to-metal dry friction tests has been obtained in the work. Practical value. The optimized content of the graphitized steel can be used for production of products working in the conditions of wear such as brake blocks of rolling stock, separators of high-speed bearings, dies and others.
Simulation and prediction of the process based on the general logistic mapping
Authors: Skalozub V. V. , Belozerov V. E. , Klimenko I. V. , Belyy B. B.
Published: April 2015

Purpose. The aim of the research is to build a model of the generalzed logistic mapping and assessment of the possibilities of its use for the formation of the mathematical description, as well as operational forecasts of parameters of complex dynamic processes described by the time series. Methodology. The research results are obtained on the basis of mathematical modeling and simulation of nonlinear systems using the tools of chaotic dynamics. Findings. A model of the generalized logistic mapping, which is used to interpret the characteristics of dynamic processes was proposed. We consider some examples of representations of processes based on enhanced logistic mapping varying the values of model parameters. The procedures of modeling and interpretation of the data on the investigated processes, represented by the time series, as well as the operational forecasting of parameters using the generalized model of logistic mapping were proposed. Originality. The paper proposes an improved mathematical model, generalized logistic mapping, designed for the study of nonlinear discrete dynamic processes. Practical value. The carried out research using the generalized logistic mapping of railway transport processes, in particular, according to assessment of the parameters of traffic volumes, indicate the great potential of its application in practice for solving problems of analysis, modeling and forecasting complex nonlinear discrete dynamical processes. The proposed model can be used, taking into account the conditions of uncertainty, irregularity, the manifestations of the chaotic nature of the technical, economic and other processes, including the railway ones.
Influence analysis of elastic deformations of the track cable on efforts in the hauling rope of aerial ropeway
Authors: Raksha S. V. , Goryachev Yu. K. , Kuropyatnik A. S.
Published: April 2015

Purpose. To estimate influence of elastic deformations of the track cable arising at movement of cars, on effort in a hauling rope of the aerial ropeway. Methodology. The method of consecutive approaches was used for research influence of elastic deformations of a track cable on effort in a hauling rope. Thus, definition of a tension of a track cable was carried out with use of the technique based on principles of modular configuration, the essence of which consists in formation of mathematical model by a combination of blocks of the formulas describing balance of the track cable on supports. Findings. The research has shown that influence of elastic deformations of a track cable on effort in a hauling rope was insignificant (less than 1 %). That points to possibility not to consider change of the track cable length, caused by its elastic properties, when modeling loading of elements of system «drive – traction rope – tension device». Also it has been found that use of the tension device of a track cable increased influence of its elastic properties on loading of rope system elements. At the same time the elastic component of the track cable tension in the test flight does not depend on a car position in the adjacent span, but only determines by the parameters of the rope system. Originality. The possibility of excluding the changes of track cable length caused by its elastic properties, when modeling loading of elements of system «drive – traction rope – tension device» was proved. Practical value. The use of these techniques and the results will simplify the mathematical model of loading of elements of the cable system and the system «drive – traction rope – tension device» as a whole.
Integration of Ukrainian industry scientific periodicals into world scientific information space: problems and solutions
Authors: Kolesnykova T. O.
Published: April 2015

Purpose. Problem of representation lack of scientists’ publications, including transport scientists, in the international scientometric databases is the urgent one for Ukrainian science. To solve the problem one should study the structure and quality of the information flow of scientific periodicals of railway universities in Ukraine and to determine the integration algorithm of scientific publications of Ukrainian scientists into the world scientific information space. Methodology. Applying the methods of scientific analysis, synthesis, analogy, comparison and prediction the author has investigated the problem of scientific knowledge distribution using formal communications. The readiness of Ukrainian railway periodicals to registration procedure in the international scientometric systems was analyzed. The level of representation of articles and authors of Ukrainian railway universities in scientometric database Scopus was studied. Findings. Monitoring of the portals of railway industry universities of Ukraine and the sites of their scientific periodicals and analysis of obtained data prove insufficient readiness of most scientific publications for submission to scientometric database. The ways providing sufficient "visibility" of industry periodicals of Ukrainian universities in the global scientific information space were proposed. Originality. The structure and quality of documentary flow of scientific periodicals in railway transport universities of Ukraine and its reflection in scientometric DB Scopus were first investigated. The basic directions of university activities to integrate the results of transport scientists research into the global scientific digital environment were outlined. It was determined the leading role of university libraries in the integration processes of scientific documentary resources of universities into the global scientific and information communicative space. Practical value. Implementation of the proposed activity algorithm of Ukrainian universities to integrate the scientific publications into the world digital environment will increase the importance of Ukrainian scientific periodicals, including the railway ones, affect the positive dynamics in the university rating, strengthen the authority Ukrainian science in the world and attract potential investors.
Assessment of accident rate at Lithuanian railways level crossings
Authors: Bureika Gintautas , Liudvinavichius Lionginas
Published: April 2015

Purpose. The most pressing problem facing the rail traffic safety experts is an accident rate at the railway level crossings. The purpose is to investigate the circumstances, which affect traffic safety at the level crossings, and to offer effective tools for experts to improve the safety the problems of these dangerous spaces of railway infrastructure. Methodology. This paper observes the logistic regression as a method to estimate the accident rate at level crossings in Lithuania. The authors have studied and evaluated the key factors affecting the safety of railway crossings. These factors are the intensity of trains and road transport means through the railway level crossing, the visibility of the approaching train from both sides of the traffic, the maximum permissible speed of the trains, the number of tracks (single track, double track, and multi-track), the level of installed alarm and automatic equipment, a density of population in this area, etc. Finally, only the factors, which might be described by mathematical expressions (numbers), were identified. Findings. By using logistic regression method, it was found that the most determinant factors at level crossings are the maximum speed of trains, poor visibility crossing (less than 1,000 m), intensity of the road traffic at crossings, and inappropriate implementation of roads crossing the rails. Based on the study results, the conclusions and recommendations were formulated which primary measures to prevent accidents at level crossing and on what level crossing should be taken urgently. Originality.Revealed trends and major causes of accidents at railway crossings of Lithuania for 2004-2011 year. The necessity of implementation of progressive technical measures for the prevention accidents on railway level crossing is proved. Practical value. About 50% of Lithuanian railway crossings do not meet the requirements of the level crossing legislation. This parameter is one of the key risk factors for traffic safety at level crossings. In order to eliminate the effect on accident due to poor visibility of moving train, it is proposed to use the "speed bumps". Question of the elimination of one level crossing is becoming more and more important due to the increased volume of traffic on the roads and railways, growing the speed of trains and the implementation of important large-scale road and rail projects.
Synthesis of digital locomotive receiver of automatic locomotive signaling
Authors: Goncharov K. V.
Published: April 2015

Purpose. Automatic locomotive signaling of continuous type with a numeric coding (ALSN) has several disadvantages: a small number of signal indications, low noise stability, high inertia and low functional flexibility. Search for new and more advanced methods of signal processing for automatic locomotive signaling, synthesis of the noise proof digital locomotive receiver are essential. Methodology. The proposed algorithm of detection and identification locomotive signaling codes is based on the definition of mutual correlations of received oscillation and reference signals. For selecting threshold levels of decision element the following criterion has been formulated: the locomotive receiver should maximum set the correct solution for a given probability of dangerous errors. Findings. It has been found that the random nature of the ALSN signal amplitude does not affect the detection algorithm. However, the distribution law and numeric characteristics of signal amplitude affect the probability of errors, and should be considered when selecting a threshold levels According to obtained algorithm of detection and identification ALSN signals the digital locomotive receiver has been synthesized. It contains band pass filter, peak limiter, normalizing amplifier with automatic gain control circuit, analog to digital converter and digital signal processor. Originality. The ALSN system is improved by the way of the transfer of technical means to modern microelectronic element base, more perfect methods of detection and identification codes of locomotive signaling are applied. Practical value. Use of digital technology in the construction of the locomotive receiver ALSN will expand its functionality, will increase the noise immunity and operation stability of the locomotive signal system in conditions of various destabilizing factors.
CFD-model of the mass transfer in the vertical settler
Authors: Nagornaya E. K.
Published: April 2015

Purpose. Nowadays the mathematical models of the secondary settlers are intensively developed. As a rule the engineers use the 0-D models or 1-D models to design settlers. But these models do not take into account the hydrodynamics process inside the settler and its geometrical form. That is why the CFD-models based on Navier - Stokes equations are not widely used in practice now. The use of CFD-models based on Navier - Stokes equations needs to incorporate very refine grid. It is very actually now to develop the CFD-models which permit to take into account the geometrical form of the settler, the most important physical processes and needs small computer time for calculation. That is why the development of the 2-D numerical model for the investigation of the waste waters transfer in the vertical settlers which permits to take into account the geometrical form and the constructive features of the settler is essential. Methodology. The finite - difference schemes are applied. Findings. The new 2-D-CFD-model was developed, which permits to perform the CFD investigation of the vertical settler. This model takes into account the geometrical form of the settler, the central pipe inside it and others peculiarities. The method of «porosity technique» is used to create the geometrical form of the settler in the numerical model. This technique permits to build any geometrical form of the settler for CFD investigation. Originality. Making of CFD-model which permits on the one hand to take into account the geometrical form of the settler, basic physical processes of mass transfer in construction and on the other hand requiring the low time cost in order to obtain results. Practical value. CFD-model is designed and code which is constructed on its basis allows at low cost of computer time and about the same as in the calculation of the 1-D model to solve complex multiparameter problems that arise during the design of vertical settlers with their shape and design features.