bluuebunny/crossref_metadata_2025 huggingface dataset:
Estrogen Receptor 1 (ESR1; ERα), not ESR2 (ERβ), Modulates Estrogen-Induced Sex Reversal in the American Alligator, a Species With Temperature-Dependent Sex Determination
Authors: Kohno Satomi , Bernhard Melissa C. , Katsu Yoshinao , Zhu Jianguo , Bryan Teresa A. , Doheny Brenna M. , Iguchi Taisen , Guillette Louis J.
Published: February 2015

All crocodilians and many turtles exhibit temperature-dependent sex determination where the temperature of the incubated egg, during a thermo-sensitive period (TSP), determines the sex of the offspring. Estrogens play a critical role in sex determination in crocodilians and turtles, as it likely does in most nonmammalian vertebrates. Indeed, administration of estrogens during the TSP induces male to female sex reversal at a male-producing temperature (MPT). However, it is not clear how estrogens override the influence of temperature during sex determination in these species. Most vertebrates have 2 forms of nuclear estrogen receptor (ESR): ESR1 (ERα) and ESR2 (ERβ). However, there is no direct evidence concerning which ESR is involved in sex determination, because a specific agonist or antagonist for each ESR has not been tested in nonmammalian species. We identified specific pharmaceutical agonists for each ESR using an in vitro transactivation assay employing American alligator ESR1 and ESR2; these were 4,4′,4′’-(4-propyl-[1H]-pyrazole-1,3,5-triyl)trisphenol (PPT) and 7-bromo-2-(4-hydroxyphenyl)-1,3-benzoxazol-5-ol (WAY 200070), respectively. Alligator eggs were exposed to PPT or WAY 200070 at a MPT just before the TSP, and their sex was examined at the last stage of embryonic development. Estradiol-17β and PPT, but not WAY 200070, induced sex reversal at a MPT. PPT-exposed embryos exposed to the highest dose (5.0 μg/g egg weight) exhibited enlargement and advanced differentiation of the Müllerian duct. These results indicate that ESR1 is likely the principal ESR involved in sex reversal as well as embryonic Müllerian duct survival and growth in American alligators.
Electrospray Ionization Mass Spectrometry of Non-Covalent Complexes Formed between N-Alkylimidazolium-Containing Zwitterionic Sulfonates and Protonated Bases
Authors: Podjava Anton , Kistkin Svjatoslav , Ausekle Elina , Priede Elina , Mekss Peteris , Zicmanis Andris
Published: February 2015

This paper describes non-covalent complexes between zwitterionic 3-(1-alkyl-3 N-imidazolio)-propane-1-sulfonates and different amines. Electrospray ionization (ESI) mass spectrometry and collision-induced dissociation were used to measure the stability of such complexes in solution and in the gas phase. Generally, zwitterionic sulfonates formed more abundant complexes with protonated 5-methylcytosine (5-MCH) than with aliphatic amines. The results show that the association constants and half-dissociation threshold energies of these complexes nonlinearly depend on the alkyl chain length of the zwitterion. It is shown that the complexes with the lowest stability exist in acetonitrile solution or in the gas phase. The factors responsible for this complicated behavior are discussed. The structure of the complexes was investigated by quantum chemical calculations using molecular mechanics and density functional theory. Hydrogen bonding is proposed as the main type of interaction responsible for the stability of ion–zwitterion complexes. In summary, the information obtained in this study could be used for the development of the new derivatization reagents for some compounds containing amidinium groups, like 5-MCH, to increase selectivity of ESI-based methods.
Dissociative Photoionization of β-Pinene: An Experimental and Theoretical Study
Authors: Cao Maoqi , Chen Jun , Fang Wenzheng , Li Yuquan , Ge Shaolin , Shan Xiaobin , Liu Fuyi , Zhao Yujie , Wang Zhenya , Sheng Liusi
Published: February 2015

We investigated the photoionization and dissociation photoionization of the β-pinene molecular using time-of-flight mass spectrometry with a tunable vacuum ultraviolet source in the region from 8.00 eV to 15.50 eV. The experimental ionization energy (IE) value is 8.60 eV using electron impact as the ionization source, which is not in good agreement with theoretical value (8.41 eV) with a G3MP2 method. We obtained the accurate IE of β-pinene (8.45 ± 0.03 eV) derived from the efficiency spectrum, which is in good agreement with the theoretical value (8.38 eV) of the CBS-QB3 method. We elucidated the dissociation pathways of primary fragment ions from the β-pinene cation on the basis of experimental observations in combination with theoretical calculations. Most of the dissociation pathways occur via a rearrangement reaction prior to dissociation. We also determined the structures of the transition states and intermediates for those isomerization processes.
Web Footprints of Firms: Using Online Isomorphism for Competitor Identification
Authors: Pant Gautam , Sheng Olivia R. L.
Published: February 2015

Competitive isomorphism refers to the phenomenon of competing firms becoming similar as they mimic each other under common market forces. With the growing presence of firms as well as their consumers and suppliers on the Web, we discover a parallel phenomenon of online isomorphism wherein the Web footprints of competing firms are found to overlap. We propose new online metrics based on the content, in-links, and out-links of firms' websites to measure the presence of online isomorphism as well as uncover its utility in predicting competitor relationships. Through rigorous analysis involving more than 2,600 firms, we find that predictive models for competitor identification based on online metrics are largely superior to those using offline data such as Standard Industrial Classification codes and market values of firms. In addition, combining online and offline metrics can boost the predictive performance. We also find that such models are valuable for identifying nuances of competitor relationships such as asymmetry and the role of industrial divisions. Furthermore, the suggested predictive models can effectively rank firms in an industrial division by their likelihood of being competitors to a focal firm as well as identify new future competitors, thus adding to a portfolio of evidence indicating their utility for managers and analysts.
Research roundup
Authors: Phillips Jane
Published: February 2015

Synopses of a selection of recently published research articles of relevance to palliative care.
The evidence base for early childhood education and care programme investment: what we know, what we don’t know
Authors: White Linda A , Prentice Susan , Perlman Michal
Published: February 2015

An expanding body of research demonstrates that high quality early childhood education and care (ECEC) programmes generate positive outcomes for children; in response, policy makers in a number of countries are making significant programme investments. No research consensus, however, has emerged around the specific types of policy intervention that are most effective. Much remains to be clarified in terms of specific policy interventions that flow from the evidence base. To respond to these important gaps in ECEC knowledge, we advance a call for a research agenda that will systematically examine the effects of early years policy instruments and settings.
Photometry and Multipolar Magnetic Field Modeling of Polars: BY Camelopardalis and FL Ceti
Authors: Mason P. A. , Zhilkin A. G. , Bisikalo D. V. , Gomez S. , Morales J. , Robinson E. L.
Published: February 2015

We present new broad band optical photometry of two magnetic cataclysmic variable stars, the asynchronous polar BY Camelopardalis and the short period polar FL Ceti. Observations were obtained at the 2.1-m Otto Struve Telescope of McDonald Observatory with 3s and 1s integration times respectively. In an attempt to understand the observed complex changes in accretion flow geometry observed in BY Cam, we performed full 3D MHD simulations assuming a variety of white dwarf magnetic field structures. We investigate fields with increasing complexity including both aligned and non-aligned dipole plus quadrupole field components. We compare model predictions with photometry at various phases of the beat cycle and find that synthetic light curves derived from a multipolar field structure are broadly consistent with optical photometry. FL Ceti is observed to have two very small accretion regions at the foot-points of the white dwarf’s magnetic field. Both accretion regions are visible at the same time in the high state and are about 100 degrees apart. MHD modeling using a dipole plus quadrupole field structure yields quite similar accretion regions as those observed in FL Ceti. We conclude that accretion flows calculated from MHD modeling of multi-polar magnetic fields produce synthetic light curves consistent with photometry of these magnetic cataclysmic variables.
Photometric and Spectroscopic Investigation of the Dwarf Nova HS 0218+3229: A Short Review
Authors: Katysheva N. , Shugarov S. , Borisov N. , Gabdeev M. , Golysheva P.
Published: February 2015

This paper is devoted to the study of the cataclysmic variable HS 0218+3229 using the photometric and spectroscopic observations.
New Insights from Inside-Out Doppler Tomography
Authors: Kotze E. J. , Potter S. B.
Published: February 2015

We present preliminary results from our investigation into using an “inside-out” velocity space for creating a Doppler tomogram. The aim is to transpose the inverted appearance of the Cartesian velocity space used in normal Doppler tomography. In a comparison between normal and inside-out Doppler tomograms of cataclysmic variables, we show that the inside-out velocity space has the potential to produce new insights into the accretion dynamics in these systems.
Application of Total Variation Minimization to Doppler Tomography
Authors: Uemura M. , Kato T. , Nogami D. , Mennickent R.
Published: February 2015

We have developed a new model of the Doppler tomography using total variation minimization (DTTVM). We demonstrated that this method can reconstruct localized and non-axisymmetric profiles possibly having sharp edges in the Doppler map. We apply this model to the real data of the dwarf nova, WZ Sge in superoutburst. DTTVM can reproduce the observed spectra with a high precision, while the previous models fail to reproduce localized sources.
SWSex Stars, Old Novae, and the Evolution of Cataclysmic Variables
Authors: Schmidtobreick L. , Tappert C.
Published: February 2015

The population of cataclysmic variables with orbital periods right above the period gap are dominated by systems with extremely high mass transfer rates, the so-called SW Sextantis stars. On the other hand, some old novae in this period range which are expected to show high mass transfer rate instead show photometric and/or spectroscopic resemblance to low mass transfer systems like dwarf novae. We discuss them as candidates for so-called hibernating systems, CVs that changed their mass transfer behaviour due to a previously experienced nova outburst. This paper is designed to provide input for further research and discussion as the results as such are still very preliminary.
Line Evolution of the Nova V5587 Sgr from Early to Nebula Phase
Authors: Kajikawa T. , Arai A. , Nagashima M. , Kawakita H. , Yamanaka M. , Kawabata K. , Kiyota S.
Published: February 2015

The spectral evolution of the nova V5587 Sgr has been monitored at Koyama Astronomical Observatory and Higashi-Hiroshima Observatory, Japan, from the early to nebula phase. The nova rebrightened several times. The spectra during the early phase showed emission lines of H α, H β, O I, He I, He II, N II, Fe II. Nova V5587 Sgr is classified into the Fe II type. The helium abundance of the nova is estimated as N(He)/N(H) = 0.134 ± 0.09. The light curve, the spectral evolution, and the helium abundance in V5587 Sgr are similar to those of the nova PW Vul.
Golden Era of Cataclysmic Variables and Related Objects II: Concluding Remarks
Authors: Hudec R.
Published: February 2015

The cataclysmic variables continue to represent important part of modern astrophysics, as demonstrated, already second time, by the productive and successful conference Golden Era of Cataclysmic Variables and Related Objects II held on Mondello (Palermo) in September 2013.
Disparities in overall and urothelial carcinoma specific mortality associated with healthcare insurance status
Authors: Siddiqui Mohummad Minhaj , M. Heney Niall , McDougal W. Scott , S. Feldman Adam
Published: February 2015

Objective: We investigated the association of insurance status with urothelial carcinoma (UC) mortality outcomes to further understand the relationship of socioeconomic status (SES) and UC disease outcomes.Materials and Methods: We performed an IRB approved, retrospective review of patients newly diagnosed with bladder UC in the years 2004 and 2005. Data were collected from January 2004 to September 2014 regarding insurance, demographics, operations, surgical pathology, and follow-up care. Insurance was characterized as lower SES and high SES based on election to utilize private vs. public sources as well as purchase of supplemental Medicare coverage.Results: A total of 213 patients were examined with a mean follow-up of 84 months. The high SES and lower SES insurance groups presented with similar disease stage (26% ≥ T2 in high SES insurance vs. 33%, P = 0.1) and grade (60% high-grade in high SES vs. 59%, P = 0.9). Significant differences were seen in one-year UC specific mortality (5% high SES insurance vs. 21%, P = 0.003) and five-year UC specific mortality (19% high SES insurance vs. 42%, P = 0.007). Upon multivariate analysis controlling for age, gender, Charlson comorbidity score, grade, stage, and metastatic disease on presentation, insurance type remained a significant risk factor for increased mortality from UC (HR = 2.6, P < 0.01). Kaplan-Meier analysis showed a persistence of lower survival with time.Conclusions: We found disparities in mortality from bladder cancer associated with source of insurance. This association persisted upon multivariate analysis as an independent risk factor for death from bladder UC.
The human β-amyloid precursor protein: biomolecular and epigenetic aspects
Authors: Nguyen Khue Vu
Published: February 2015

Beta-amyloid precursor protein (APP) is a membrane-spanning protein with a large extracellular domain and a much smaller intracellular domain. APP plays a central role in Alzheimer’s disease (AD) pathogenesis: APP processing generates β-amyloid (Aβ) peptides, which are deposited as amyloid plaques in the brains of AD individuals; point mutations and duplications ofAPPare causal for a subset of early-onset familial AD (FAD) (onset age <65 years old). However, these mutations in FAD represent a very small percentage of cases (∼1%). Approximately 99% of AD cases are nonfamilial and late-onset, i.e., sporadic AD (SAD) (onset age >65 years old), and the pathophysiology of this disorder is not yet fully understood. APP is an extremely complex molecule that may be functionally important in its full-length configuration, as well as the source of numerous fragments with varying effects on neural function, yet the normal function of APP remains largely unknown. This article provides an overview of our current understanding of APP, including its structure, expression patterns, proteolytic processing and putative functions. Importantly, and for the first time, my recent data concerning its epigenetic regulation, especially in alternative APP pre-mRNA splicing and in the control of genomic rearrangements of theAPPgene, are also reported. These findings may provide new directions for investigating the role of APP in neuropathology associated with a deficiency in the enzyme hypoxanthine-guanine phosphoribosyltransferase (HGprt) found in patients with Lesch-Nyhan syndrome (LNS) and its attenuated variants (LNVs). Also, these findings may be of significance for research in neurodevelopmental and neurodegenerative disorders in which the APP gene is involved in the pathogenesis of diseases such as autism, fragile X syndrome (FXS) and AD, with its diversity and complexity, SAD in particular. Accurate quantification of various APP-mRNA isoforms in brain tissues is needed, and antisense drugs are potential treatments.
Impact of Coil Geometry on Magnetohydrodynamic Flow in Liquid Aluminium and Its Relevance to Inclusion Separation by Electromagnetophoresis
Authors: Kennedy Mark William , Bakken Jon Arne , Aune Ragnhild Elizabeth
Published: February 2015

Magnetohydrodynamic (MHD) flow will be produced in liquid aluminium by gradients in the Lorentz forces created by the interactions of induced currents and the time-varying magnetic field of an induction coil. The magnitude of the velocity field is driven by the curl of the Lorentz forces. Practical coils are “Short” and produce magnetic fields having both lower flux densities and Lorentz forces than very “Long” or infinite coils. Unlike infinite coils, the magnetic fields of “Short” coils contain both axial and radial components, which vary with position and thereby produce powerful MHD mixing. When such a coil is used with the objective of achieving non-conductive particle migration in a liquid metal by electromagnetophoresis, the obtained mixing effects can be highly detrimental. In the present study different coil geometries and induced Lorentz forces with resulting MHD mixing are modelled (COMSOL®4.4), and the obtained Lorentz forces compared to analytical results.
Alsatian versus Standard German: Regional Language Bilingual Primary Education in Alsace
Authors: Harrison Michelle Anne
Published: February 2015

This article examines the current situation of regional language bilingual primary education in Alsace and contends that the regional language presents a special case in the context of France. The language comprises two varieties: Alsatian, which traditionally has been widely spoken, and Standard German, used as the language of reference and writing. The advantages of learning Standard German have been highlighted by language-in-education policy-makers: as well as being the written form of the regional language, German is promoted as the most widely spoken language in the European Union, the language of neighbouring countries, an asset in the search for employment and an aid to learning another powerful language in our increasingly globalized world, namely English. Nevertheless, Alsatian can be, and in some cases is being, employed in the classroom, although it remains in a minority position in comparison to Standard German. Based on original research undertaken in the region, the article aims to explore current classroom practices, which are sometimes found to be incongruous with official language-in-education policy. It analyses the language attitudes of parents and considers the effect of these attitudes on the promotion of Alsatian and Standard German. Practices and attitudes in city and small town locations are compared to evaluate the influence of urban and peri-urban settings. As the transmission of Alsatian is no longer guaranteed in the home, the article investigates whether the school can promote this traditional, non-standardized regional variety alongside the dominant standard languages, and whether parents wish for this to happen.
DEVELOPMENT OF CRITERIA OF CHARGE AND DISCHARGE EFFICIENCY OF SOLID STATE OF HEAT ACCUMULATOR
Authors: Belymenko S. S. , Ishchenko V. O.
Published: February 2015

Purpose. Development of similarity criteria for different modes of operation of the solid-state heat accumulator working due to accumulation of heat in the volume of the heat storage material without phase transition, and the creation of systematic criteria of heat accumulator efficiency for determination the weight / size parameters and operating modes at the design stage. Methodology. To achieve the objectives of the study the theory of similarity and dimensional analysis were used as well as planning and carrying out techniques of physical experiments. Findings. Based on the theory of similarity and dimensional analysis similarity criteria operation of solid-state heat accumulators, under given basic parameters were obtained. These are performance criteria for charge, discharge and full criterion. Three theorems of similarity theory in application to the solution of engineering problems were used. The criterion of efficiency of the heat accumulator charge characterizes the effectiveness of achieving the specified value of the specific amount of heat in the material of heat accumulator under charge, under received materials, geometrical ratios, and heat flow of the heat input. The efficiency criterion characterizes the discharge efficiency of the heat accumulator, at the accepted materials; mass of heat-retainer and the total accumulated amount of heat when the value of the heat flow and the time of discharge. Full coefficient of the heat accumulator performance characterizes the efficiency of the heat accumulators for a full cycle. Originality. Accordingly to the analysis the implementation of any system of solid-state heat accumulator is possible on the basis of structural schemes of this type of device. The similarity criteria of the efficiency of the charge, the efficiency of discharge and the full criterion of solid-state heat accumulators’ efficiency based on the solid storage material without phase transition were obtained. Practical value. Criteria presented in this work are of a comparative nature. In accordance with the obtained criteria we can compare designed and existing heat accumulators that are similar to structures. Feasibility analysis indicates that the proposed assessment methodology of solid-state heat accumulators’ efficiency in different modes of operation is effective, technically feasible and allows determining the weight / size parameters and modes of operation of the solid-state heat accumulator at the design stage.
FREQUENCY DETERMINATION OF HIGH-FREQUENCY LINK FOR PERCPECTIVE ELECTRIC ROLLING STOCK
Authors: Zabarylo D. O.
Published: February 2015

Purpose. Total mileage of Ukrainian electric railways is distributed approximately equally between the areas of direct and alternating current. A double system of electric rolling stock is used to pass jointing places of different current kinds without train’s stop. Therefore introduction of such rolling stock of a new concept that is using an asynchronous traction drive is prospective for Ukrainian railways. Apart from advantages a rolling stock of similar concept has significant disadvantages, it is pulse energy consumption from the power supply, and it can affect the reliability of track automatic devices, and consequently, the train traffic safety. In addition the specific power of traction transformer is considerably inferior to the power density of other traction elements. The promising schemes using an intermediary link of increased frequency, which consist of a transformer and inverter, have been proposed for disadvantages amendments. The main task for the further introduction of prospective circuit is to determine the operating frequency for high frequency link. Methodology. The method of thermal parameters calculation of semiconductor devices has been used for determination switching transistors of maximum operating frequency. To obtain analytical expressions curves of energy, released during the IGBT (insulated-gate bipolar transistor) switching from its current load approximation method is used. Findings. The permissible frequency of lowfrequency link is determinated by load current of intermediate transformer. Operating frequency range of a link depending on load current has been determined. A comparative analysis of the switching characteristics of 65 class IGBT production by companies Infineon and ABB has been performed. Originality. The further determination method of the maximum operating frequency of intermediate link for circuit with high-frequency transformer has been developed. Practical value. The established operating frequency range of the highlevel link will develop further research of tractive circuit with highfrequency transformer use for double feed electric rolling stock with asynchronous tractive drive. It will evaluate the introduction effectiveness of similar configuration circuits.
EFFICIENCY IMPROVEMENT OF TRANSPORT SERVICE BY TROLLEY BUSES BASED ON THE LEVELS OF THEIR POWER DEMAND
Authors: Aulin V. V. , Plokhov I. O. , Holub D. V.
Published: February 2015

Purpose. Use efficiency improvement of trolley buses in passenger traffic based on power levels of electric energy input and terms adjustment of their maintenance. Methodology. In order to achieve this goal conformance of electric energy input by trolleybus to the transported amount of passengers taking into account characteristics of the route is offered to establish. The major indicators of the trolleybus operation are: speed of a race on lines, number of tractive motor firing, voltage and amperage in the network that were taken with accountants from a dashboard. Research results were tabulated and recorded with DVR. Along with the study of power consumption of electric energy input by a trolleybus passenger count was carried out too. Findings. The directly proportional dependence between the level of energy consumption by a trolleybus and the number of passengers for constant performance route was determined. Originality. As the criteria for evaluating the effectiveness of the trolleybus operation on the route is proposed to use the ratio between electricity consumption and number of passengers for these characteristics of the route. This is confirmed experimentally. The obtained formulas give the possibility to balance the force work and consequently the volume of energy consumption during the trolleybus movement on the rise and the descent. Practical value. The proposed criterion can be used to adjust the terms of maintenance on the individual program, that means individual maintenance (IM). Type of work performed at the IM should be determined on the basis of diagnostic data of the vehicle (V). The principles of IM were formulated: 1) the primary task is planned and preventative strategy to identify and eliminate troubleshooting and technical actions; 2) operational control of the vehicle (V) technical condition on the basis of prediction of its state using the proposed criteria, that takes into account the dependence of power consumption to the number of passengers in the characteristics of the route; 3) individual approach to evaluate the technical condition of each specific vehicle (V); 4) individual prediction of the frequency of the maintenance and vehicle condition.
DIRECTIONS FOR THE DEVELOPMENT OF DOMESTIC TOURISM IN UKRAINE
Authors: Martseniuk L. V.
Published: February 2015

Purpose. Each country of the world pays great attention to the development of tourism in the country, since a significant part of revenues comprises the revenues from providing the tourist services. Ukraine faced the problem of a significant reduction in the volume of tourist flows, aging of capital fund, lack of investments for its renovation. Purpose of the article is to develop an optimal control mechanism of tourist flows, justifying the need for the development of inbound and domestic tourism. Methodology. A system analysis of the competitiveness problem of the tourism industry in the area of passenger rail transportations, theoretical principles of economics in the field of domestic tourism efficiency and management of tourist flows are the theoretical and methodological basis of the research. Findings. The authors developed an improved mechanism for managing tourist flows. It differs from the existing one by the expansion of services for tourists in the territory of Ukraine. The development analysis of inbound and domestic tourism, restoration narrow-gauge railways, as well as the creation of special tourist trains were proposed. As a result the following objectives should be achieved: 1) increase in the share of tourism and resorts in the structure of gross domestic product up to the level of developed countries; 2) the number of employees in tourism and resorts equal to the level of developed countries; 3) increase in total number of rooms in hotels and other certified accommodation facilities up to the level of developed countries; 4) creation of the effective system of monitoring the quality of tourist services; 5) creating an investment climate to attract the investments into development of the tourism, engineering, transport and communal infrastructure; 6) improvement of tourists safety, providing effective protection of their rights, legal interests and property. Originality. The author presented the theoretical generalization and new solution of the scientific problem. They lie in the development of theoretical and methodological approaches to justification of the organization of tourist rail transportations and activization of measures to realize the project to restore the effective functioning of the mountain railways with 750 mm width in the Carpathian region of Ukraine, with the possibility to incorporate them to the extensive international tourism network. Practical value. The rational measures according to the directions of tourism flows management proposed by the author will significantly increase the country revenues from tourism.
UPGRADING OF ECONOMIC SIMULATION METHODS FOR INCREASING EFFICIENCY OF INVESTMENTS
Authors: Myamlin S. V. , Zhyzhko K. V.
Published: February 2015

Purpose. Main aim of research is improving the investment`s efficiency of industrial`s enterprises and economic sectors. Methodology. Methodological approaches to estimation of investment`s efficiency are improved by means of insights and analysis methods as well as by the methods of mathematical and economic modeling. Findings. Efficient mechanism for estimation rational level of using of investments was created and tested. The approach allows defining rational dependence between basic components of investment process (increase of income, volume of involving investment and time of investment project realization). Originality. Authors developed new economic-mathematical approach with aim of rational using of financial resources during the period of capital deficit. Approach based on solving problem of multi-objective optimization by means of using of set function. Application of proposed approach is up-to-date because of unstable economic situation in Ukraine. Practical value. As a result of using the developed economic-mathematical approach the rational options of investment can be found. The approach provides an opportunity to analyze a large number of possible investment projects and reduce it to the most profitable for investor. Developed approach also can be used in forming process of principles of highly efficient national economy.
MODELING OF FINANCIAL AND ECONOMIC SECURITY OF TRANSPORT ENTERPRISES BASED ON FACTOR ANALYSIS
Authors: Novikov A. O. , Novikova M. M.
Published: February 2015

Purpose. Financial and economic security defines sustainable financial development of the enterprise, that is balanced and sustained, it justifies the necessity to achieve it through the effective use of all kinds of resources that are available at the enterprise. The purpose of the article is to improve the methodical estimation bases of the financial and economic security state at the transport enterprises, taking into account sector specificity for making the effective management decisions. Methodology. Theoretical and methodical basis of the research is in the systematic analysis of the process of assessing and modeling of the financial and economic security of enterprises in transport sector, theoretical principles of economic science in the sphere of financial efficiency evaluation of economic activities in a changing environment. Findings. The structure of the financial and economic security of the enterprises in transport industry was studied. The internal communication between the partial indicators of the investigated process for selection of necessary and sufficient quantities of the most indicative factors of influence were defined. Partial components of the financial and economic security based on the results of its modeling formation at the transport enterprises using factor analysis methods were systematized. Originality. Authors improved the methodological basis of quantitative evaluation of the financial and economic security level at the transport enterprises on the basis of the aggregate partial indicators, which was formed with industry specificity. This allows evaluating complex estimation of the degree of external and internal factors influence on the financial and economic security at the enterprises to ensure the effective management decisions making in order to achieve planned financial performance indicators of their activity. Practical value. Certain trends of forming ability of the transport companies to protect their financial interests are common for the studied objects. They explain 72% of the total variability of partial characteristics and reflect the modern process features of financial management and economic security. This justifies practical use expediency of the formed aggregate of the partial indicators of the financial and economic security as the basic parameters of the integrated assessment of its state at the transport industry enterprises for providing timely detection and prevention possible threats of company functioning in the financial environment.
THE IMPROVEMENT OF MAINTENANCE SERVICE FOR TRACTION NETWORKS EQUIPMENT ON THE BASE OF PROCESS APPROACH
Authors: Mironov D. V.
Published: February 2015

Purpose. The new methods development for improving the maintenance service for equipment of traction networks in order to increase its efficiency and quality. Methodology. In world practice of solving problems related to the quality of products and services is usually achieved by introducing quality management system in to the enterprises. The provisions of quality management system were used for solving the problem. The technologies of process engineering were used for describing the main stages of maintenance service. Findings. The development of high-speed movement and growth of its intensity, the use of electric rolling stock of a new generation require the introduction of new methods diagnostics of equipment technical state and improvement of the existing maintenance system and repair of power supply. Developing a model of business-processes, their optimization with using techniques of process engineering and system management is needed for the transition to the management system based on the process approach. From the standpoint of the process approach and in accordance with the requirements of the quality management system (ISO 9001-2009), the operation of the E (Department of electrification and power supply) infrastructure sector is represented as a scheme of business-processes in which the guaranteed supply with electricity of railway and third-party consumers is defined as the main business-process of management. Each of the sub-process of power supply for consumers is described in details. The use methods and main stages of process approach for sample management system reorganization were investigated. The methodology and the application method of PDCA (Plan-Do-Check-Act) closed loop to the equipment maintenance system were described. The monitoring process of traction networks maintenance using the process approach was divided into components after investigations. The technical documentation of maintenance service was investigated in details. Ways to improve business-processes of E (Department of electrification and power supply) management were described. Originality. Maintenance improvement ways for equipment of traction networks using process engineering technologies and quality of electric power supply were proposed. Practical value. Using the provisions of the quality management system to the process of maintenance equipment will let ensure the improvement of process quality by increasing the reliability indices of electric equipment, the service level of consumers and changes of production processes focused on the efficiency increase of the sector activity.
STUDY OF TIME DEPENDENCE AND SPECTRAL COMPOSITION OF THE SIGNAL IN CIRCUIT OF AC ELECTRIC POINT MOTORS
Authors: Buryak S. Yu. , Havriliuk V. I. , Hololobova O. O.
Published: February 2015

Purpose. The paper is aimed to establish the dependence of changes in the time domain and spectral components of the current in the circuit of the AC electric point motor on its technical condition, to identify the common features for the same type of damage. It is necessary using the analysis of the received signals to carry out the remote diagnosis and determination of faults and defects of electric point motors. In addition it suggested to accelerate the process of the failure, malfunction and damage search. Authors propose the automated approach to the service of remote floor automation equipment, which is located in the envelope of trains. Reduction of the threat to life and health of staff by reducing the residence time in the zone of train movement. Reduce the impact of human factors n the result of service. Methodology. The paper studies the structure, parameters and characteristics, the operation and maintenance characteristics of the AC electric point motors. Determination of the main types of possible faults in the process depending on the operating conditions. Presentation of the electric motor as an object of diagnosis. Findings. The time dependences of the current in the circuit of electric point motor for its various states was obtained. The connection between the technical condition of electric point motor and the performance of current curve in time and spectral domains was established. The revealed deviations from the reference signal were justified. According to the obtained results it was made the conclusion. Originality. A method for diagnosing the state of the AC electric point motor by the time dependence and the spectral composition of the current in its circuit was proposed. The connection diagram to the motor windings based on non-infringement of electric parameters of connection circuit in the actual operating conditions was applied. Practical value. The obtained results suggest the possibility and feasibility of further development of the principles of remote diagnosis based on the analysis of temporal and spectral domains of the current curve in the circuit of the AC electric point motor. The implementation and practical application in operation as a separate system for the collection, analysis, processing and data communication is also real and rational. The given system makes possible tracking the changes in key parameters and forming the proposals on impact measures on the existing situation, as well as the ability to predict the state of the objects on the basis of the dependency determination of the previous changes.
METHODOLOGY FOR DETERMINING THE VALUE OF COMPLEXITY PARAMETER FOR EMERGENCY SITUATION DURING DRIVING OF THE TRAIN
Authors: Horobchenko O. M.
Published: February 2015

Purpose. During development of intelligent control systems for locomotive there is a need in the evaluation of the current train situation in the terms of traffic safety. In order to estimate the probability of the development of various emergency situations in to the traffic accidents, it is necessary to determine their complexity. The purpose of this paper is to develop the methodology for determining the complexity of emergency situations during the locomotive operation. Methodology. To achieve this purpose the statistical material of traffic safety violations was accumulated. The causes of violations are divided into groups: technical factors, human factors and external influences. Using the theory of hybrid networks it was obtained a model that gives the output complexity parameter of the emergency situation. Network type: multilayer perceptron with hybrid neurons of the first layer and the sigmoid activation function. The methods of the probability theory were used for the analysis of the results. Findings. The approach to the formalization of manufacturing situations that can only be described linguistically was developed, that allowed to use them as input data to the model for emergency situation. It was established and proved that the exponent of complexity for emergency situation during driving the train is a random quantity and obeys to the normal distribution law. It was obtained the graph of the cumulative distribution function, which identified the areas for safe operation and an increased risk of accident. Originality. It was proposed theoretical basis for determining the complexity of emergency situations in the train work and received the maximum complexity value of emergency situations that can be admitted in the operating conditions. Practical value. Constant monitoring of this value allows not only respond to the threat of danger, but also getting it in numerical form and use it as one of the input parameters for the locomotive intelligent control system. The decision on further control actions will be based on it.
INFLUENCE OF PHYSICAL AND HEAT PROCESSES ON THE STRUCTURE AND PROPERTIES OF HIGH-CHROMIUM CAST IRON DURING MACHINING
Authors: Netrebko V. V.
Published: February 2015

Purpose. Analysis of changes of high-chromium cast irons' structure and properties under the influence of physical and heat factors during mechanical machining. Methodology. The methodology of evaluation of the cutting tool's force and heat influence on the machined material has been developed and applied. Cast specimens underwent preliminary turning to obtain the diameter of 25 mm. The microsection was made on the end surface of the specimen with the length of 50 mm. Standard plates with sizes 10×10 mm made of VK8 according to the State Standard 19051-80 were used in the turning process. Findings. Force influence on the specimens made of highchromium cast iron caused strain hardening during machining. Temperature influence on the structure and properties of high-chromium cast iron during machining caused increase of the plasticity characteristics of the metallic base in the cutting area, fragmentation of the carbide phase and elimination of the strain hardening. During turning with cutting depth 0.8 mm only force influence of the cutting tool on the specimen took place. Carbide inclusions in the surface layer didn't undergo sufficient changes; at the same time the metallic base was strain-hardened to 1 100 HV50. As it was drawn away from the turning surface, the microhardness of the metallic base was decreasing and equaled to 500…520 HV50 at the distance of 1.2 mm from the turning surface. Strain hardening was not observed at the depth of more than 3mm. Cutting depth increase up to 1.5 mm caused simultaneous influence of force and heat factors. The temperature influence revealed in increasing of metallic base plasticity in the specimen's surface layers. Strain hardening of heated surface layers didn't occur. While drawing away from the cutting surface, the influence of the temperature factor decreased, when the influence of force factor remained the same. Due to the base plasticity decrease the strain hardening occurred. The metallic base strain was hardened to 490…520 HV50. The overall heating of the specimen caused the decrease of strain hardening depth to 0.4 mm. Originality. The methodology of change evaluation of high-chromium cast iron structure and properties under the influence of physical and heat factors during mechanical machining has been elaborated. Practical value. This methodology allows developing the recommendations for choices of highchromium cast iron machining modes and conditions.
MATHEMATICAL MODEL DEVELOPMENT OF HEAT AND MASS EXCHANGE PROCESSES IN THE OUTDOOR SWIMMING POOL
Authors: Shaptala M. V. , Shaptala D. E.
Published: February 2015

Purpose. Currently exploitation of outdoor swimming pools is often not cost-effective and, despite of their relevance, such pools are closed in large quantities. At this time there is no the whole mathematical model which would allow assessing qualitatively the effect of energy-saving measures. The aim of this work is to develop a mathematical model of heat and mass exchange processes for calculating basic heat and mass losses that occur during its exploitation. Methodology. The method for determination of heat and mass loses based on the theory of similarity criteria equations is used. Findings. The main types of heat and mass losses of outdoor pool were analyzed. The most significant types were allocated and mathematically described. Namely: by evaporation of water from the surface of the pool, by natural and forced convection, by radiation to the environment, heat consumption for water heating. Originality. The mathematical model of heat and mass exchange process of the outdoor swimming pool was developed, which allows calculating the basic heat and mass loses that occur during its exploitation. Practical value. The method of determining heat and mass loses of outdoor swimming pool as a software system was developed and implemented. It is based on the mathematical model proposed by the authors. This method can be used for the conceptual design of energy-efficient structures of outdoor pools, to assess their use of energy-intensive and selecting the optimum energy-saving measures. A further step in research in this area is the experimental validation of the method of calculation of heat losses in outdoor swimming pools with its use as an example the pool of Dnipropetrovsk National University of Railway Transport named after Academician V. Lazaryan. The outdoor pool, with water heating-up from the boiler room of the university, is operated year-round.
DETERMINATION OF THE SAFETY FACTOR FOR THE FATIGUE STRENGTH OF THE BEARING STRUCTURES OF RAILROAD CAR BODIES DURING TRANSPORTATION BY RAILROAD FERRIES
Authors: Lovskaya A. A.
Published: February 2015

Purpose. To determine assurance coefficient by supporting structures fatigue of car bodies during transportation by the railway ferries. Methodology. The operating conditions of cars in international railway-water communication have been investigated in previous works for the solution of this problem. To solve the problem there were conducted researches of dynamic features of car bodies transporting by the railway ferries in conditions of the sea storm. A mathematical model of car bodies movement was made up and accelerations acting on them in placements on the decks were determined. During determination of accelerations the actual meteorological characteristics of the Black Sea during a storm were taken into account. The assurance coefficient fatigue by supporting structures of car bodies by the railway ferries was determined and it was found that under regular loading of the car body n ≈ 2,0 . It is higher than the admissible value. Findings. Comparison of obtained acceleration values with the accelerations acting on car bodies when operating on main-line routes showed that they have exceeded the acceleration specified in the regulations approximately on 40%. It proves the need of accounting the loads acting on car bodies during transportations by the railway ferries when designing new generation cars. Originality. There was proposed a mathematical model of car bodies movement by the railway ferries in the conditions of sea storm. It gives the possibility of determining the accelerations of car bodies placed on the decker rail ferries taking into account the hydrometeorology characteristics. Practical value. The results of researches can be used when designing new generation cars to provide their strength during the combination of railway and water transportation. It gives an opportunity to develop measures as to the adaptation of cars bodies to the interaction with the fastenings of railway ferries by means of equipping their bearing constructions with special fastening assembly units. Such technical solution will allow decreasing expenses for unscheduled repair of cars while transporting them by railway ferries and providing safety of combined transport traffic.