bluuebunny/crossref_metadata_2025 huggingface dataset:
Calculated disturbances for evaluation of dynamical properties of freight cars
Authors: Ushkalov V. F. , Lapina L. G. , Mashchenko I. A.
Published: April 2015

Purpose. To form realizations of the calculated disturbances for studying the dynamic properties of railway vehicles. Methodology. Records of the track-test car for one of the typical track sections of the Pridneprovsk railroad are the basic data for building the disturbance components. To derive the true geometric parameters of the railway gauge the records of the track-test car using a double-point metering circuit are transformed considering the transfer function of the measuring system. A model of the calculated disturbances is presented as the four components: a symmetric vertical irregularity determined as a semi-sum of vertical irregularities of the right and left rails; an oblique-symmetric vertical irregularity of the track determined as a semi-difference of vertical irregularities of the right and left rails; horizontal irregularities of the right and left rails. Acceptability criterion of the constructed disturbances is a relationship between the values of the dynamical properties factors of cars and the corresponding experimental data. Findings. The three techniques for the calculated disturbances forming are proposed. The first technique uses records of the track-test car for the track with a sufficiently high amount for given track conditions as components of the calculated disturbances. In so doing symmetrical vertical components of disturbances resulting from records of settling are corrected with the mass and stiffness parameters of the car under consideration. The second technique uses building and applying the theoretical realizations of irregularities corresponding to a real track according to a spectral analysis. The third technique ensures a polyharmonic model of disturbances, the parameters of which are the values of the basic frequencies and amplitudes that are typical for irregularities of a railway track. A possibility of practical applying of the constructed models of disturbances are presented using an example for defining the standardized factors of the dynamical properties of empty and loaded open cars. Comparison of the calculated factors and experimental data demonstrated its assurance. Originality. The three models of the calculated disturbances that can be used for calculating estimation of the maximal values of the standardized dynamical factors of freight vehicles are proposed. Practical value. The research results ensure an acceptable predicted evaluation of the dynamical properties factors for the designed or refitted vehicles of railway rolling stock, refinement of the values of the certain system parameters at the stage of prototypes, reduction of the expenses for performance trials, etc.
Dynamic performance of freight cars on bogies model 18-1711
Authors: Bubnov V. M. , Myamlin S. V. , Mankevych N. B.
Published: April 2015

Purpose. To analyze the results of study of dynamic parameters of the tank-car model 15-1900 and gondola car model 12-1905, equipped with the bogies model 18-1711 with axle loading of 25 ton and unified according to major parts and joints with the cars of previous generation. According to results of the study to conclude about the possibility of using bogies model 18-1711 as the running parts of the freight rolling stock of the new generation of 1520 mm track with increased axle loading. Methodology. The dynamic performance of the rolling stock running parts directly affects the safety of railway traffic. Experimental studies of the car dynamic qualities are an important step in the modernization of existing bogie constructions and in the creation of the new ones. These tests allow one to confirm the results of theoretical studies and to check the correctness of the constructive solutions. Findings. Basic results of dynamic studies are presented as the graphs of dynamic performance dependencies on the motion speed of the experimental train. Results show that the freight cars on the bogies model 18-1711 have satisfactory dynamic properties meeting current regulatory requirements. Originality. The dynamic characteristics of freight cars on bogies model 18-1711, which give a complete view of the car loading allow us to estimate the dependency of the car dynamic performance on the bogie design parameters. Practical value. The bogie model 18-1711 with axle loading 25 ton can be used as a freight car undercarriages of the new generation of 1520 mm track.
Once again about determination of saving of energy for traction due to partial cut–off of traction engines of electric rolling stock
Authors: Getman G. K. , Vasiliev V. Ye.
Published: April 2015

Purpose. In general the well known methods for determination of energy saving due to the partial traction engines cut-off based on their comparison to efficiency coefficient or to the power of energy losses do not allow objective estimation of efficiency of these measures and in a number of cases result in erroneous results and errors. The search for new more advanced methods for determination of energy saving at the partial cut-off of the traction engines is needed. Methodology. The method of calculation determination of energy saving when partial cutting-off of the traction engines is offered. It is based on the use of rationality coefficient as the loading mode of the electric power consumption for the measuring instrument of transportation activity. Findings. Using the given mathematical expressions it is possible to determine the energy saving in both the relative and absolute values and set the terms (motion speed and route gradient), under which the energy saving will take place. Originality. The method of the task solving, which is based on the evaluation of energy consumption differences for the compared variants (not on the comparison of efficiency coefficient or differences of power of energy losses) is offered. Practical value. The given methodology allows obtaining more exact conclusions in relation to the electric power consumption, as the comparison of energy losses power or the efficiency coefficient does not determine precisely the electric power consumption for traction. Therefore the conclusions based on the comparison of power of energy losses or efficiency coefficient can appear inexact.
Modeling of the track and rolling stock interaction
Authors: Khalipova N. V.
Published: April 2015

Purpose. Interaction of system’s elements of "carriage–track" modelling requires consideration of various criteria, it also requires analysis of many uncertainty and randomness factors’ influence on the basic parameters to ensure optimal or rational parameters of the system. The researching of interactions’ process requires new theoretical approaches to formulation of objectives, based on a generalization of existing modeling approaches. The purpose of this work is development of interaction models between track and rolling stock based on multiple structures of objects. Methodology. Dedicated and formed the main evaluation criteria of dynamic interaction between track and rolling stock optimization - quality assurance and safety of transportation process, improving of their efficiency and reducing of prime cost’s. Based on vector optimization methods, proposed model of rolling stock and track’s elements interaction. For the synthesis of the model used mathematical machine of multiple objects structures. Findings. Generalized approaches to modeling in the interaction of rolling stock and track for different structural elements of the system under different exploitation conditions. This theoretical approach demonstrated on the examples of modeling of passenger and freight cars with track under different exploitation conditions. Originality. Proposed theoretical approach to the problem of track and rolling stock interaction, based on a synthesis of existing models by using of multiple objects structures. Practical value. Using of proposed model allows to structure key data and rational parameters of rolling stock and track interaction’s modeling and to formulate optimal and rational parameters of the system, to determine the effective exploitation parameters and measurement system for rational use of infrastructure.
Design improvement of the locomotive running gears
Authors: Myamlin S. V. , Neduzha L. O.
Published: April 2015

Purpose. To determine the dynamic qualities of the mainline freight locomotives characterizing the safe motion in tangent and curved track sections at all operational speeds, one needs a whole set of studies, which includes a selection of the design scheme, development of the corresponding mathematical model of the locomotive spatial fluctuations, construction of the computer calculation program, conducting of the theoretical and then experimental studies of the new designs. In this case, one should compare the results with existing designs. One of the necessary conditions for the qualitative improvement of the traction rolling stock is to define the parameters of its running gears. Among the issues related to this problem, an important place is occupied by the task of determining the locomotive dynamic properties on the stage of projection, taking into account the selected technical solutions in the running gear design. Methodology. The mathematical modeling studies are carried out by the numerical integration method of the dynamic loading for the mainline locomotive using the software package «Dynamics of Rail Vehicles » («DYNRAIL»). Findings. As a result of research for the improvement of locomotive running gear design it can be seen that the creation of the modern locomotive requires from engineers and scientists the realization of scientific and technical solutions. The solutions enhancing design speed with simultaneous improvement of the traction, braking and dynamic qualities to provide a simple and reliable design, especially the running gear, reducing the costs for maintenance and repair, low initial cost and operating costs for the whole service life, high traction force when starting, which is as close as possible to the ultimate force of adhesion, the ability to work in multiple traction mode and sufficient design speed. Practical Value. The generalization of theoretical, scientific and methodological, experimental studies aimed at further improvement of the running parts for the mainline locomotives of promising designs is urgent for improving the rolling stock design. The observed improvements of the design features of the running gear elements for some types of the modern mainline locomotives, providing the necessary dynamic parameters of the vehicle movement are relevant; they have the practical value and can be used for further developments.
Lightweight concretes with fly–ash of Prydniprovsk thermal power station
Authors: Netesa M. I. , Palanchuk D. V. , Netesa A. M.
Published: April 2015

Purpose. Determination of conformities to law of influence of expense of components of easy concretes, which turn out on the basis of local afterproducts of industry, on their basic properties under conditions of enhanceable efficiency of the use of cement. Methodology. Experimental studies on optimization of structures and properties of concrete were carried out with use of mathematical planning experiments methods. All experiments were carried out on orthogonal design with three variables. Cement, water and additives PLKP-2 consumption were taken as varied factors. Findings. Vast experimental studies on determination of rational compositions of concrete mixtures were conducted with the use as fillers of granulated slag from iron and steel plant named after Petrovskiy and Dnepr sand, as binding agent Krivoy Rog portland-cement II/B-Ш-400, as filler fly-ash of Pridneprovsk Thermal Power Station. Efficiency coefficient of cement use was adopted as basic criterion of concrete composition rationality, it is determined on the relation of the attained durability per unit weight of used cement. For greater efficiency coefficient of cement use regularity of rational grain composition of components previously obtained was adopted, it is provided at a ratio of a large fraction consumption to medium and small 52:23:25, and their sizes are approximately 100:10:1. Experimental studies with use of mathematical planning experiments method were carried out. By results of their processing isofields were constructed according to the strength and effectiveness of the use of cement ratio of the studied factors. Originality. By strength comparative tests of hardened concrete with various local secondary resources, modified with complex plasticizer PLKP-2 additive, it was found that lightweight concrete with the density of 1700…1800 kg/m3 and concrete compressive strength from 5 to 20 MPa on the basis of granulated slag from the iron and steel plant named after Petrovskiy filled with fly-ash of Pridneprovsk Thermal Power Station during ensuring of rational grain composition of components with a ratio of major components of the fractions to medium and small 52:23:25 are the most effective. Practical value. Compositions of lightweight fine grained mixture based on granulated slag from the iron and steel plant named after Petrovskiy filled with fly-ash of Pridneprovsk Thermal Power Station and modified with complex plasticizer PLKP-2 additive were determined. They provide required concrete compressive strength within 5…10 MPa at a reduced cement consumption by approximately 20% as compared to the traditionally used compositions for these purposes.
The influence of pre-heat treatment on white cast irons plasticity
Authors: Myronova T. M.
Published: April 2015

Purpose. The development of heat treatment modes of white cast irons for structure changes in their eutectic constituent, namely in disturbing the monolithic structure of ledeburite colonies cementite structure and eutectic net continuity. Also the mentioned heat treatment modes are targeted to the eutectic net shift for the most suitable position from the point of plastic deforming. Methodology. The hypoeutectic white cast irons with 2.92…3.35 % carbon content and additionally alloyed by 3.18 % vanadium have been used as the research materials. The mentioned alloys have been pre-heat treated and hot twist tested. Findings. The research results showed that the carbide net breaking by plastic deforming leads to cast irons mechanical properties increasing but has difficulties in implementation due to the white cast irons low plasticity. The influence of different pre-heat treatment modes on structure and plasticity of white hypoeutectic cast irons have been investigated. They include the isotherm soaking under the different temperatures as well as multiply soakings and thermo-cycling. The influence of eutectic level, as well as pre heat treatment modes on different composition white cast irons hot plasticity have been investigated. Originality. It was determined that the heat treatment, which leads to double α→γ recrystallization under 860 – 950 °С and reperlitization under 720-680 °С results in significant increase of plasticity, as well as in un-alloyed and alloyed by vanadium white cast irons. It takes place due to carbide matrix phase separation in ledeburite colonies by new phase boundaries forming especially due to carbide transformations under vanadium alloying. Practical value. The implementation of pre-heat treatment with phase recrystallization resulted in hypoeutectic white cast irons plasticity increasing. The obtained level of cast iron plasticity corresponds to the one of carbide class steels, which ensures the successful deformation by forging and rolling.
Technical approach to the efficiency determination of high-speed trains
Authors: Momot A. V.
Published: April 2015

Purpose. The aim of this article is to develop an approach and formulate arrangements concerning the definition of the economic appropriateness of high-speed movement implementation in Ukraine. Methodology. The economic feasibility for appropriateness of high-speed movement organization in Ukraine is an investment project, which involves step-by-step money investment into the construction. It will let get an annual profits from the passenger carriage. To solve such problems we use net present value, which UZ or newly created companies can get during the project realization and after its completion. Findings. Obtained studies can state the fact that the technical approach for full effectiveness definition of a construction and high-speed passenger trains service taking into account the cost of infrastructure, rolling stock, the impact of environmental factors, etc. was determined. Originality. We propose a scientific approach to determine the economic effectiveness of the construction and high-speed main lines service. It includes improved principles of defining the passenger traffic, the cost of high-speed rails construction, the number of rolling stock; optimizes income and expenditure calculations in the context of competitive advantages and the external factors impact on the company. A technical approach for the calculation of future traffic volumes along the high-speed line was improved. It differs essentially from the European one proposed by the French firm «SYSTRA», as it allows taking into account additional transit traffic through Ukraine. It helps to distribute the passengers on separate sections proportionally to the number of cities population, which are combined by high-speed main line, subject to the average population mobility, travel time and the coefficient that takes into account the frequency of additional passenger trips on a given section, depending on the purpose (business trip, transfer to a plane, recreation, etc). Practical value. The above mentioned factors records increase the validity of administrative decisions relating to ensuring the functioning of high-speed traffic effectiveness.
Diagnostics of the wheel thread of railway rolling stock
Authors: Buryak S. Yu.
Published: April 2015

Purpose. At present, the devastating impact of faulty wheels on rails on the move is a major problem of railway transport. This factor is one of the most important, which causes the shift from traditional manual methods of verification and external examination to the automated diagnostic system of rolling stock in operation. Methodology. To achieve this goal the main types of wheel damages and the way they appear are analyzed. The methods for defects and abnormalities of the wheel thread determining as well as their advantages and disadvantages were presented. Nowadays these methods are under usage in both the international practice and in the one of the CIS countries. Findings. The faulty wheel sound on the move was researched and analyzed. The necessity of using the automated system, enabling one to reduce significantly the human factor is substantiated. Originality. The method to determine the wheel thread damage on the basis of a sound diagnostic is proposed. Practical value. Automatic tracking system of the wheels condition allows performing their more qualitative diagnostics, detecting a fault at the early stage and forecasting the rate of its extension. Besides detecting the location of the faulty wheel in the rolling stock, it is also possible to trace the dynamics of the fault extension and to give the recommendations on how to eliminate it.
The efficiency of the use of chemical addivites for manifacture of concrete products
Authors: Pristinskaya V. V.
Published: April 2015

Purpose. To study various additives of a domestic production and to estimate expediency of their use for products of transport construction. Methodology. The study was conducted by introducing a superplasticizer and active mineral additives Findings. The complex additive should include effective superplasticizing admix, as well as additives which operate stiffening and hardening kinetics, air retaining substances and defoaming agents, dispersion and fine-dispersion mineral fillers. In recent years organo-mineral modifiers such as superplasticizer - an active mineral additive (microsilica, metakaolin, ash) obtained a wide circulation. Originality. The impact of various additives on the concrete quality is studied. It is found out that the complex additive PLKP deserves the special attention because it allows producing a concrete of very high durabilityand is recommended for use in railroad ties. Thus, the introduction of additives in the concrete can significantly increase the durability and reliability of concrete products. Practical value. Results of the research can be used to improve the reliability and durability of concrete structures. This calls for further researches on the selection of the concrete mixture with complex additive PLKP, as well as adding the active mineral components.
Determination of dynamic performance of freight cars taking into account technical condition of side bearers
Authors: Myamlin S. , Neduzha L. , Ten O. , Shvets A.
Published: April 2015

Purpose.  The railway transport plays an important role in social and economic life of the country and carries out the large containment of transportation activities. The transport industry should migrate towards innovation changes and increase its significance as an important transit subsystem on the way of renovation of both the infrastructure and the strategy of all transportation process components including the interaction with other transport modes. At present the life sets strategic challenges for the railway branch, and the basic goals among them are as follows: high-speed train traffic development, increase of the weight of freight trains, new rolling stock development etc. Due to the urgency of this subject, the researchers should cope with the task devoted to one of aspects of improving the freight transportation efficiency, namely to the study of effects of various factors and characteristics of technical conditions of the freight cars running gears (which are unavoidable to arise during operation) on their basic dynamic indices. The deviations of technical conditions of running gears from the normal state of the wedge system of bogie swing suspension also play an important role among them. The purpose of the paper is to investigate the influence of different factors of the technical conditions of freight car running gears (size deviation in both the bearers and the wedge system during operation) on their basic indices – coefficients of horizontal and vertical dynamics, vehicle body acceleration, frame strength, and derailment stability coefficient. Methodology. The study was conducted by numerical integration and mathematical modeling of the freight car dynamic loading using the software package “Dynamics of Rail Vehicles” (“DYNRAIL”). Findings. As a result of the research for freight car dynamic coefficients determination taking into account technical conditions of the side bearers, the dependencies of the basic freight cars dynamic coefficients on the parameters of side bearers (the clearances in the side bearers and the wedge system conditions of the bogie swing suspension) considering running speed in the tangent and curved track sections of minor and mean radii were obtained. Originality. The impact of the technical condition of the car running gears on the traffic safety factors is determined.Practical value. The theoretical research results in determination of freight car dynamic indices taking into consideration the technical conditions of the side bearers of freight cars allow for an adequate assessment of effect of the freight car bogies’ technical conditions, namely the bearers parameters, on the railway traffic safety factors (coefficients of horizontal and vertical dynamics, vehicle body acceleration, frame strength and derailment stability coefficient).
Tank head parameters assessment of influence on tank car boiler stress and strain state
Authors: Bespalko S. V. , Bogachev V. I.
Published: April 2015

Purpose. The purpose of the investigation is to estimate such value of a tank head depth wherein the maximum capacity of vehicle is provided and a tank vessel durability meets the requirements. Methodo-logy. The problem solution was carried out with using  the finite element analysis program NASTRAN. The finite element model is a tank shell of the railway eight-wheel tank car of model 15-1443. The load was presented as pressure. The value was accepted equal 0,4 MPa. The finite element model strain-stress state was analyzed. The tank head depth changed ranging from 0,2 m to 1,5 m. Findings. The rational tank head depth was 0,47 m from the tank vessel durability condition. This allows to improve the basic tank car parameters. It means to increase the tank vessel volume and to increase  the capacity at 0,7 ton. Authors has investigated that an additional increase of the tank vessel volume and the vehicle capacity can be achieved when the tank head sheets thickness as high as 13 mm. In this case it is necessary to recognize that the rational tank head depth is 0,4 m. Tank capacity can be increase at 1 ton. Originality. This paper presents the method of analysis of the tank car volume increase. The tank car volume increase and thus а capacity of vehicle increase allows to improve the car productiveness. Calculations results allow to give the dependence of the maximum equivalent stresses in a tank head which the depth of the one change. Practical value. It is shown that the tank head depth reduction will allow to improve parameters of the existing railway tank when the tank vessel durability meets the requirements. Investigation results can be used when new tank cars are designed.
Solution of the problems of system reliability by modeling the stress-strain state of rail track using the theory of elastic waves propagation
Authors: Bondarenko I. O. , Kurgan D. M.
Published: April 2015

Purpose:The analysis of opportunities of the current practical methods for the track strength calculation and their comparison with the proposed method of calculation using the theory of elastic waves propagation.Methodology. The analytical analysis of equations set–up and their solution of the stress state of the track elements by different techniques is applied. Simulation method is used to create a model of railway track.Findings.Initially, the equations describing a stress state of the track elements have differential components for the time and dynamic loading accounting. However, for the majority of problems solving, they are significantly simplified – the difficult dependences are replaced with the empirical coefficients, some parameters are simply neglected. The limits of calculation applicability, imposed on them by certain admissions are resulted. The possibilities of the track model construction based on the theory of elastic waves propagation are given as an alternative. Then time of stress effect, the involved masses and other indicators are subordinated to the front of the waves propagation, and the balance equations are based on dynamic presentation of the elasticity theory. Originality.The general principles of track model formation based on the theory of elastic waves propagation as an alternative to the equations with differential components for time and dynamic loads accounting are proved. Practical value. These developments can be used as a tool for solving the problems related to the railway track reliability.
Development of dynamic models of wagons on models 18-9810 and 18-9855 bogies taking into account wheel wear research
Authors: Saidova A. V. , Orlova A. M.
Published: April 2015

Purpose. Wear parameters clarification in wear simulation is an actual goal because of absence of corresponding data for freight cars in condition of using them on Russian railways. Research is devoted to development of dynamic models of wagons on three-peace two-axle models 18-9810 and 18-9855 bogies with maximum axle-loads 23,5 ts and 25 ts, and to choice of factors, with varying which parameters in the model of wheel wear can be identified. Methodology. The problem is solved by method of mathematic simulation in «MEDYNA» software. Wear calculation is based on abrasive wear theory (Archard’s theory). Findings. Clarification of wheels’ wear model may be done with varying of friction coefficient between wheel and rail for different wheel profile areas (flange and tread), wear coefficient in Archard’s model for mild and heavy wear and transition between them. Originality. Dynamic models of universal gondola on models 18-9810 and 18-9855 bogies are developed. It is established, that rail treads irregularities size effect wheel wear insignificantly, when car is running on circle track of constant radius. Practical value. Developed dynamic models of wagons on models 18-9810 and 18-9855 bogies may be used in wear simulation, determination of car running characteristics, interaction of car and rail of different type, construction, condition and etc. Research results of some factors influence on freight car wheel wear may be interesting for people, who study this problem.
Transport progress as a pledge of national economy development
Authors: Myamlin S. V.
Published: April 2015

Purpose. To determine the influence of transport branch development through the state order implementation for rolling stock and infrastructure projects in the basic economic branches. Methodology. On the basis of situation and content analyses the impact of particular science branches development on improvement of transport modes is analyzed. The role of engineering approach for both the problem solving of the stagnant technologies negotiation and new designs creation as well as solving the economic problems at a national level is observed. Findings. The impact of transport development on the national economy improvement is analyzed; during this the active role of scientific and technical progress of transport branch is investigated. The efficient means to increase the effectiveness of national economy are analyzed; one of these means is the state order for production of the basic industry branches. All the components of the production process while launching the innovational rolling stock manufacture, including the results of scientific, project and production organizations researches are taken into account. Practical value. It is proved that, provision of the state order for domestic enterprise production is the main way of national economics strengthening and the basic direction of the life quality improvement in the country. The state order for transport branch production will solve a number of social problems of regional and state level.
The method of the correlation and dispersion defining of the total power components in the electric transport devices
Authors: Nikitenko A. V. , Kostin M. O.
Published: April 2015

Purpose. Development and theoretical ground of the analytical method for the calculation of the active, reactive and total powers in the electric traction devices, taking into consideration the non-stationary character of the stochastic processes change of the voltage and current in the elements of these systems. Methodology. The mathematical methods of the random processes theory and the “discrete electrical engineering” methods are used for solving the main problem of this paper. Findings. The Method of the Correlation and Dispersion is developed for definition of the active power, the reactive power by Fryse and the total power of the devices in the elements of the electric traction system of the main-line railways. The method is based on the well-known concepts of auto- and inter-correlation functions of the random processes which govern the feeder voltages and the currents in the traction power supply subsystem as well as the currents and voltages of the electric rolling stock. The method developed in this paper allows estimating the powers of both stationary and non-stationary processes. This method can be used for the analysis of both the traction mode and the regenerative braking mode of the electric rolling stock. The total power components were calculated for the one of the feeder areas of the Prydniprovsk railway using this method. The results show the significant flow of the reactive power in the traction power supply system. This fact is also confirmed by the high values of the reactive power coefficient. Originality. Scientific novelty of the research is consisted in the following. Firstly, for defining the active and reactive powers in elements of the traction power supply system the new method (the Method of Correlation and Dispersion) is created and grounded. This method is different from other existing methods because it takes into consideration the varying non-stationary character of the chance processes of the feeder and substation voltages and currents. Secondly, in the DC traction power supply system the large values of the exchange reactive power by Fryze were created for the first time. Practical value.The method and its technique allow calculating the main energy coefficients for the traction power systems such are the reactive power coefficient, the main and additional active power losses in the power circuit of the electric rolling stockand the traction power supply system.
Developing measures to improve strength indices of supporting structures for head cars of diesel trains DR1A on the basis of experimental-and-theoretical works
Authors: Bondarev O. M. , Gorobets V. L. , Yagoda D. O. , Bondarev O. O.
Published: April 2015

Purpose. The objective is to determine the stress-strain state of supporting structures of the head car body and the traction transmission unit, which can be created in the operation of emergency situations, and to develop the measures aimed at improving the stress-strain state of these elements. Methodology. In order to achieve this objective, in performing the work an experimental determination of efforts and stress levels in the most loaded elements of supporting structures as well as the traction transmission units was conducted; design models for the theoretical determination of stress and effort levels were developed. Findings. Based on the analysis of the calculation results the best options for the upgrades, which have been put into the basis of proposals aimed at improving the strength indices, were revealed. Originality. Based on the experimental and theoretical studies, scientific monitoring of development works on modernization and improvement of strength indices of supporting structures of head cars of diesel trains DR1A was performed. Practical value. The technical solution to the measures, which are to be carried out beyond the limits of assigned operation lifetime for diesel train of the series specified was developed and transferred to the Ukrzaliznytsia experts to introduce the proposed measures on improving the strength indices.
COMPARATIVE ANALYSIS OF MODELS OF RAILWAY LOADS C14 AND LM71 FOR GIRDER BRIDGES
Authors: Artemov V. Ye. , Raspopov A. S.
Published: April 2015

Purpose. The article analyzes the railway load LM71 for the purpose of its application in national design projects of the railway girder bridges. Purpose of the article is harmonization of national design codes of enginnering structures with the European standards (Eurocodes). Methodology. Analytical calculation methods (influence lines), the matrix analysis and computer programming are used in the article. Findings. Deflected mode parameters of the railway bridges under the influence of loads C14 and LM71 have certain differences. The extent of these differences depends on length, material of drift structures and also on dynamic coefficients. These dependences should be considered in national design codes and in harmonized with Eurocodes standards. In the further researches relationships between load C14 and models SW, HSLM taking into account various dynamic effects and trains speedis planned to determine. Originality. The presented results, in particular deflected mode parameters (including loads with dynamic coefficients), obtained for the first time. Practical value. Results of research are used in National Annex to the National Standard of Ukraine NSTU-N B EN 1991-2:2010. Eurocode 1. Actions on structures. Part 2. Traffic loads on bridges (EN 1991-2:2003).
Methodology of determination of admissible speeds of train movement on difficult sections of railroad plan
Authors: Kurhan M. B. , Kurhan D. M. , Khmelevska N. P. , Baidak S. YU.
Published: April 2015

Purpose. Determination of improvement ways of admissible speeds of train movement on the difficult sections of а railroad plan. Methodology. Mathematical modeling of the train traffic is used to achieve the purpose of research. The average weighted speed and elevation of outer rail is predicted on this basis. Findings. The case analysis of the speeds determination in curved sections of track was carried out. The above mentioned track sections adversely affect the ride comfort and the intensity of the way disorder, as well as the reasons that contribute to the speed limits traffic on the railways of Ukraine. The technique of performing the calculations for determining the permissible train speeds was developed and tested on real curves of railways, were the accelerated movement of trains was introduced. Proposals on automate calculations in distances and services by way of determining the permissible speeds in curves were developed. Originality. Methodology of determining the permissible motion speeds and elevation of outer rails on the difficult sections of the railway plan was developed. This approach allows you to get a rational decisions on reorganization of plan based on local conditions. Practical value. The developed technique of definition of admissible speeds of motion in curves was implemented as a program DopShvid. The program was tested on real railway sections, where the accelerated train motion was introduced.
Influence of electric spark on hardness of carbon steel
Authors: Vakulenko I. O. , Proydak S. V. , Stradomski Z. , Diadko V. A.
Published: April 2015

Purpose. The purpose of work is an estimation of influence of an electric spark treatment on the state of mouldable superficial coverage of carbon steel. Methodology. The steel of fragment of railway wheel rim served as material for research with chemical composition 0.65% С, 0.67% Mn, 0.3% Si, 0.027% P, 0.028% S. Structural researches were conducted with the use of light microscopy and methods of quantitative metallography. The structural state of the probed steel corresponded to the state after hot plastic deformation. The analysis of hardness distribution in the micro volumes of cathode metal was carried out with the use of microhardness tester of type of PMT-3. An electric spark treatment of carbon steel surface was executed with the use of equipment type of EFI-25M. Findings. After electric spark treatment of specimen surface from carbon steel the forming of multi-layered coverage was observed. The analysis of microstructure found out the existence of high-quality distinctions in the internal structure of coverage metal, depending on the probed area. The results obtained in the process are confirmed by the well-known theses, that forming of superficial coverage according to technology of electric spark is determined by the terms of transfer and crystallization of metal. The gradient of structures on the coverage thickness largely depends on development of structural transformation processes similar to the thermal character influence. Originality. As a result of electric spark treatment on the condition of identical metal of anode and cathode, the first formed layer of coverage corresponds to the monophase state according to external signs. In the volume of coverage metal, the appearance of carbide phase particles is accompanied by the decrease of microhardness values. Practical value. Forming of multi-layered superficial coverage during electric spark treatment is accompanied by the origin of structure gradient on a thickness. The effect of the superficial work-hardening from a spark according to a level can be an alternative to majority of thermal and chemical-thermal technologies of treatment of metallic materials.
Modeling Of the Phytoplankton Dynamics Considering the Mechanisms of Ectocrine Regulation
Authors: Жданова О.Л. , Zhdanova O.L.
Published: April 2015

In the paper set of models that take into account various mechanisms for ectokrine regulation of phytoplankton growth are proposed and studied. The considered models are
following: with a nonlinear dependence of phytoplankton growth rate on the concentration of the metabolite in the environment; with a metabolite, which increases both
the growth rate and mortality of the phytoplankton; with two different metabolites, one of which increases the rate of growth of phytoplankton, and the second - is reduced.
These models are modifications of the classical space-time model of the dynamics of phytoplankton, linking change in its density and the concentration of nutrients
in space and time, which do not consider the mechanism of ectokrine growth regulation. By the means of the model it has been shown, that the metabolites secreted by algae
are able to stabilize the growth of phytoplankton in conditions of excessive nutrient availability.
Breeding Common Bean for Resistance to Common Blight: A Review
Authors: Singh Shree P. , Miklas Phillip N.
Published: April 2015

Common blight [caused by Xanthomonas campestris pv. phaseoli Smith (Dye)] is a major bacterial disease causing >40% seed yield and quality losses in common bean (Phaseolus vulgaris L.) worldwide. Use of resistant cultivars is crucial for its effective, economical, and environment friendly integrated management and control. Common blight resistant germplasm are found in the primary, secondary, and tertiary gene pools of the common bean. Substantial progress has been made in understanding the pathogenic variation, germplasm screening methods, identification of resistant germplasm, genetics of resistance, identifying and mapping molecular markers linked with resistance quantitative trait loci (QTL), introgressing resistance from the secondary and tertiary gene pools, transferring resistance from the Middle American common bean landraces to Andean cultivars and germplasm lines, and pyramiding or combining resistance from diverse germplasm sources into common bean. Backcross, pedigree, gamete, and recurrent selection methods or their modifications singularly or in combination have been used to introgress and pyramid resistance. Also, molecular markers with or without direct disease screening have been used for breeding for resistance. However, Andean and Middle American common bean cultivars with high levels of combined resistance to less‐aggressive and aggressive bacterial strains in all aerial plant parts are not available. We will review progress achieved in breeding for resistance, briefly describe problems faced, and discuss strategies for integrated genetic improvement for common blight resistance for cultivar development.
Variation for Grain Mineral Concentration in a Diversity Panel of Current and Historical Great Plains Hard Winter Wheat Germplasm
Authors: Guttieri Mary J. , Baenziger P. Stephen , Frels Katherine , Carver Brett , Arnall Brian , Waters Brian M.
Published: April 2015

Wheat (Triticum aestivum L.) grain mineral concentrations tend to decrease as yields increase, therefore, breeding for yield improvement may reduce wheat nutritional quality. The objectives of this study were to survey grain mineral concentration in Great Plains hard winter wheat to assess (i) the heritable variation for grain mineral concentrations in the germplasm pool, (ii) the effects of more than 50 yr of wheat breeding on mineral concentrations, and (iii) opportunities to exploit the underlying physiological relationship between grain protein concentration (GPC) and grain mineral concentration to improve nutritional quality. Grain mineral concentrations were measured in a panel of 299 winter wheat genotypes grown in 2012 and 2013 in Oklahoma and Nebraska. Cadmium and Li concentrations were most heritable across environments, and the low heritabilities of Fe and Zn concentrations will challenge direct breeding efforts, particularly within low‐yield environments that minimize genetic variance. Within the subset of cultivars released from 1960 to 2014, grain yield increased 0.58 to 1.25% yr−1, and Zn concentration decreased 0.15 to 0.26% yr−1, relative to the reference cultivar Scout 66. Grain concentrations of Fe, P, and S also trended lower over this time period. Significant genetic variation persists within contemporary germplasm. Among 93 cultivars released since 2000, Zn concentration max/min ratios ranged from 1.5 to 2.3, depending on environment. The positive interrelationship between GPC and grain Fe and Zn concentrations could be exploited in a yield‐neutral breeding strategy that selects genotypes based on positive grain protein deviation (GPD) in multiple environments.
Application of the Smith‐Hazel Selection Index for Improving Biomass Yield and Quality of Switchgrass
Authors: Jahufer M. Z. Z. , Casler M. D.
Published: April 2015

Apart from the importance of switchgrass (Panicum virgatum L.) as forage for livestock, it is useful as a high‐value cellulosic biofuel feedstock. Breeding for a biofuel crop is complicated by the existence of multiple platforms for conversion of biomass to energy. Our main objective was to investigate the relative merits of single‐trait selection, correlated response to selection, and Smith‐Hazel‐index‐based selection for the following traits: biomass dry matter yield (YLD), ethanol (ETOH), Klason lignin (KL), and high heating value (HHV). The genetic analysis was based on a 2‐yr data set generated from evaluation of 144 half‐sib (HS) families in sward‐plot trials at Arlington and Marshfield, WI. There was significant (P < 0.05) additive genetic variation among the families for all traits and for family × site interaction for the traits HHV and YLD. The estimates of narrow sense heritability on a HS family mean basis ranged from 0.37 for YLD to 0.51 for KL. Genetic correlation of YLD with ETOH, HHV, and KL were 0.38, 0.27, and 0.01, respectively. The index constructed to increase YLD and ETOH and reduce KL was most successful for a fermentation platform. This index enabled identification of families for enhancing ethanol production that would have been missed if selection was based solely on YLD. The index weighted to increase YLD and KL best suited a combustion platform. Both of these two indices had economic impacts superior to any other selection index evaluated.
Treatment of emulsified oils by electrocoagulation: pulsed voltage applications
Authors: Genc Ayten , Bakirci Busra
Published: April 2015

The effect of pulsed voltage application on energy consumption during electrocoagulation was investigated. Three voltage profiles having the same arithmetic average with respect to time were applied to the electrodes. The specific energy consumption for these profiles were evaluated and analyzed together with oil removal efficiencies. The effects of applied voltages, electrode materials, electrode configurations, and pH on oil removal efficiency were determined. Electrocoagulation experiments were performed by using synthetic and real wastewater samples. The pulsed voltages saved energy during the electrocoagulation process. In continuous operation, energy saving was as high as 48%. Aluminum electrodes used for the treatment of emulsified oils resulted in higher oil removal efficiencies in comparison with stainless steel and iron electrodes. When the electrodes gap was less than 1 cm, higher oil removal efficiencies were obtained. The highest oil removal efficiencies were 95% and 35% for the batch and continuous operating modes, respectively.