bluuebunny/crossref_metadata_2025 huggingface dataset:
Sixth Graders’ Use of Technologies in Learning, Technology Attitudes and School Well-Being
Authors: Halonen Niina , Hietajärvi Lauri , Lonka Kirsti , Salmela-Aro Katariina
Published: December 2016

Using digital technologies (DT) in learning is expected to foster students' school engagement. International surveys, however, show that using of technologies for learning in Finnish schools is still far from optimal. This study was conducted as a part of Mind the Gap project. The aim was to examine how frequently students use technologies for learning, what kinds of attitudes they hold towards using technologies, and how these, compared to the students’ overall school experiences, explain academic well-being. Gender differences were also examined. The data was collected with a questionnaire in 2013 from 36 schools in Helsinki (n=735, 56% female, ~12-13 years) which assessed the students’ use of and attitudes to digital technologies in learning, perceptions of school, school value, school engagement and burnout. Gender differences were analysed with t-tests. Relationships between technology, school-perception measures and academic well-being were analysed with linear regression. DTs were reportedly used in school mostly for knowledge acquisition and mechanical tasks. However, most students reported wanting to use technology more and experienced it to foster school engagement. Regarding technology-related indicators, fear-of-failing and digital learning engagement were related to lower school value and also burnout symptoms. As DTs were used in learning infrequently, their contribution to school well-being was expectedly low. However, students’ attitudes for DTs were related to problems in school well-being. Thus, we propose a need for novel pedagogical practices for using DTs, while maintaining good student-teacher relationships and conditions. To conclude, how technologies are used, instead of how much, should be the key question.
Measurements to Assess and Programmes to Promote Socio-Emotional Competences in Children With Intellectual Disability
Authors: Faria Sónia Maria de Matos , Esgalhado Graça , Pereira Cristina Maria Gonçalves
Published: December 2016

Socio-emotional Competences (SEC) in children with Intellectual Disability (ID) are essential to their personal, social and academic success. It is important to identify measurements that have been effective in assessing SEC in children with ID, as well as programmes that have proven successful with this population. This theoretical perspective on the state of the art of measurements to assess and promote SEC led us to a wide range of instruments, although only a few have been used with children with ID. The Test of Emotion Comprehension (Pons, Harris, & Doudin, 2002) seems to be the most suitable to use with these children, presenting several advantages including a Portuguese version, its use with the population with ID, its user-friendliness and appealing material. Regarding intervention programmes, there is evidence of the use of some with this population, showing relevant outcomes. Nevertheless, all these programmes provide us a solid basis for allowing a construction and validation of a new one in order to overcome some gaps in the promotion of SEC in children with ID.
Racial Disparities in Medicaid Asthma Hospitalizations
Authors: Silber Jeffrey H. , Rosenbaum Paul R. , Calhoun Shawna R. , Reiter Joseph G. , Hill Alexander S. , Guevara James P. , Zorc Joseph J. , Even-Shoshan Orit
Published: December 2016

BACKGROUND AND OBJECTIVES:

Black children with asthma comprise one-third of all asthma patients in Medicaid. With increasing Medicaid coverage, it has become especially important to monitor Medicaid for differences in hospital practice and patient outcomes by race.

METHODS:

A multivariate matched cohort design, studying 11 079 matched pairs of children in Medicaid (black versus white matched pairs from inside the same state) admitted for asthma between January 1, 2009 and November 30, 2010 in 33 states contributing adequate Medicaid Analytic eXtract claims.

RESULTS:

Ten-day revisit rates were 3.8% in black patients versus 4.2% in white patients (P = .12); 30-day revisit and readmission rates were also not significantly different by race (10.5% in black patients versus 10.8% in white patients; P = .49). Length of stay (LOS) was also similar; both groups had a median stay of 2.0 days, with a slightly lower percentage of black patients exceeding their own state’s median LOS (30.2% in black patients versus 31.8% in white patients; P = .01). The mean paired difference in LOS was 0.00 days (95% confidence interval, –0.08 to 0.08). However, ICU use was higher in black patients than white patients (22.2% versus 17.5%; P < .001). After adjusting for multiple testing, only 4 states were found to differ significantly, but only in ICU use, where blacks had higher rates of use.

CONCLUSIONS:

For closely matched black and white patients, racial disparities concerning asthma admission outcomes and style of practice are small and generally nonsignificant, except for ICU use, where we observed higher rates in black patients.
Off-Label Use of Medical Devices in Children
Authors:   SECTION ON CARDIOLOGY AND CARDIAC SURGERY,   SECTION ON ORTHOPAEDICS, Jenkins Kathy J. , Beekman Robert H. , Vitale Michael G. , Hennrikus William L. , Minich L. LuAnn , Ackerman Michael J. , Berger Stuart , Jaquiss Robert Douglas Benjamin , Mahle William T. , Marino Bradley S. , Vincent Julie Anne , Morrow William R. , Otsuka Norman Y. , Abzug Joshua M. , Ganley Theodore John , Herman Martin Joseph , Hyman Joshua E. , Segal Lee S. , Shaw Brian Anthony , Schwend Richard M.
Published: December 2016

Despite widespread therapeutic needs, the majority of medical and surgical devices used in children do not have approval or clearance from the Food and Drug Administration (FDA) for use in pediatric populations. The clinical need for devices to diagnose and treat diseases or conditions occurring in children has led to the widespread and necessary practice in pediatric medicine and surgery of using approved devices for “off-label” or “physician-directed” applications that are not included in FDA-approved labeling. This practice is common and often appropriate, even with the highest-risk (class III) devices. The legal and regulatory framework used by the FDA for devices is complex, and economic or market barriers to medical and surgical device development for children are significant. Given the need for pediatric medical and surgical devices and the challenges to pediatric device development, off-label use is a necessary and appropriate part of care. In addition, because of the relatively uncommon nature of pediatric conditions, FDA clearance or approval often requires other regulatory pathways (eg, Humanitarian Device Exemption), which can cause confusion among pediatricians and payers about whether a specific use, even of an approved device, is considered experimental. This policy statement describes the appropriateness of off-label use of devices in children; the use of devices approved or cleared through the FDA regulatory processes, including through the Humanitarian Device Exemption; and the important need to increase pediatric device labeling information for all devices and especially those that pose the highest risk to children.
Risk factors associated with early childhood caries – a case control study
Authors: Lima Marina De Deus Moura , Brito-Neto Zacarias Soares , Amaral Heylane Oliveira , Lima Cacilda Castelo Branco , Moura Marcoeli Silva de , Moura Lúcia De Fátima Almeida de Deus
Published: December 2016

Objective: The aim of this study was to determine the risk factors associated with early childhood caries (ECC).Methods: It was an observational retrospective case-control study. The case group consisted of all patients diagnosed with ECC in the records of an active program of maternal and child care. The control group was composed of an equal number of children, matched for gender and age, who attended the program and did not have ECC. The process of data collection consisted of completing a pre-established schedule to analyse variables related to the mother/caregiver and child.Statisticalanalysis was performed using the chi-squared and odds ratio (OR), with alpha (α) = 0.05.Results: History of caries in the mother (OR=2.61; CI 95%=1.45-4.67) and father (OR=1.72; CI 95%=1.02-2.89) were key determinants in the child being diagnosed with ECC.Conclusions: The risk factors associated with ECC were the following: no oral hygiene acceptance, nocturnal feeding duration of more than 16 months, a daily intake of sugar greater than 4 times a day, a Baume type II maxillary arch, fewer than 3 consultations with the program, and a history of decay in the parents.
Assistance to people with mental disabilities: a discussion from the social integration
Authors: Almeida Tahyná Duda de , Santos Paula Mendes , Angelo Gabriela Lopes , Teixeira Suélen Alves , Oliveira Ana Cristina
Published: December 2016

Objective: While the process of social inclusion have promoted respect for the person with mental disability, the stigma against this individual is still very present in society, so that individual identified from their difference, now identified as being a weak, fragile and sometimes abnormal and identified as someone with a determination that can break barriers, even the difference. Considering that the social integration of individuals with disabilities still means a great challenge for society, this study sought to discuss issues related to targeted assistance to the population with mental disabilities within this integration process. The way society perceives and relates to people with disabilities is a repetition of the speech and behavior of its own professionals and programs involved in social integration and rehabilitation of these individuals.Conclusion: The educational institutions of human resources, and assistance programs aimed at the disabled, need to promote reflections on the densest kind of discourse and practices used in everyday life of these people and their families. They should not act based on rejudice.
Clinicopathological, histochemical and immunohistochemical aspects of angioleiomyoma of the cheek: a case report
Authors: Matheus Paula Daniele , Martins Manoela Domingues , Meurer Luise , Sant´Ana Lucas N. , Santa’Ana Filho Manoel
Published: December 2016

Introduction: Leiomyomas are benign smooth muscle neoplasms that preferably affect the genitals, skin, and gastrointestinal tract, being rarely seen in the oral cavity. They  re commonly classified into three microscopic patterns: solid leiomyoma, angioleiomyoma (ALM), and epithelioid leiomyoma. The most frequently reported sites of occurrence of oral ALM are the lip (48.6%), palate (21.1%), buccal mucosa and tongue (9.2%), and intraosseous lesions (8.3%).Case report: A 62 years old male presented a painless swelling in the left cheek. In this report histopathological and immunohistochemical analysis were made to confirm the diagnosis, since several lesions were possible. The treatment was local surgical excision of the tumor.
Determinants of gingival recessions in Portuguese adults
Authors: Lapa João , Veiga Nélio J. , Ribeiro Claudia , Marques Tiago , Santos Nuno Malta , De Sousa Manuel
Published: December 2016

Objectives: The objective of this study consisted in determining the prevalence of gingival recession and potential risk factors associated in a sample of patients that had a dental appointment in the University Clinic of the Portuguese Catholic University in Viseu, Portugal.Methods: We conducted an epidemiological observational cross-sectional study where a sample of 101 patients was assessed. The participants were subjected to a questionnaire and an intra-oral clinical examination was made in order to assess gingival recessions.Results: The prevalence of recession was 85.1%. The presence of habits and a high plaque index are associated with the onset of recessions and its severity. The aesthetic condition was influenced only in 14.0% of the cases and just 17.4% of the patients with gingival recession had tooth hipersensibility. There is a stronger association between the development of recessions and using a brushing technique based mostly on horizontal movements and brushes with harder bristles.Conclusion: Although further studies need to be applied in a more representative sample, we conclude that the majority of the analyzed sample has already suitable oral health behaviors, however, some need to be modified as the understanding of the need to change certain habits to prevent development of recessions.
The knowledge of children on tooth care: a qualitative and quantitative approach
Authors: Pacheco Karina Tonini dos Santos , Silva Junior Manoelito Ferreira , Arcieri Renato Moreira , Garbin Artênio José Isper , Garbin Cléa Adas Saliba
Published: December 2016

Objective: To assess the knowledge of children who participated in an Oral Health Educational Program (OHEP) on the subject "tooth care”.Methods: The study was conducted on children aged 6 to 9 years, participating in activities developed twice a week in an OHEP during one academic year. Data were collected by redactions and drawings. Drawings were analyzed according to the methodology proposed by Taylor, Roth and Mayberry. The redactions were analyzed according to the citation of hygiene items and the content presented, taking as theoretical reference the content analysis of Bardin.Results: All children mentioned the toothbrush and toothpaste as oral hygiene items. As a negative aspect to oral health, candies were mentioned by 74.4% of children, with greatest citations of confections, chewing gum and lollipop. All redactions mentioned aspects of toothbrushing, such as frequency, technique and/or quality. The consequences of “not caring” were also present, and were related to dental caries, edentulism, halitosis, pain, and personal relationship. The reason for caring was also mentioned, and was related to the importance of teeth for the individual, and “clean”, “healthy” and “bright” teeth.Conclusion: The children presented satisfactory understanding on tooth care, evidencing the importance of oral health education programs for this population.
Evaluation of the antimicrobial effect of calcium hydroxide combined to different vehicles
Authors: Piana Tatiana Dantas , Gesteira Maria de Fátima Malvar , Carvalho Erica Dos Santos , Matos Josilene Borges Torres Lima , Franca Monica , Araújo Leandro Miranda de , Da Silva Silvio José Albergaria
Published: December 2016

Objective: To evaluate the potentiating effect of different substances in antimicrobial action of calcium hydroxide.Methods: The agar diffusion method, was used with well technique, to analyze seven substances associated to calcium hydroxide to make some pastes, they are: chlorexidine, saline, anesthetic, malvatricin, propolis, hypochlorite, paramonochlorophenol.Results: The pastes with malvatricin and paramonochlorophenol presented greater inhibition zones against Enterococcus faecalis.Conclusion: There was potentialization in antimicrobial effect of calcium hydroxide when associated to paramonochlorophenol and to malvatricin especially against Enterococcus faecalis. Low increase of the antimicrobial capacity was observed when using chlorexidine as vehicle to calcium hydroxine paste.
The missing dimension of knowledge transfer from subsidiaries to headquarters: The case of Oil and Gas companies in CEE region
Authors: Velinov Emil , Gueldenberg Stefan
Published: December 2016

The paper identifies knowledge management determinants of knowledge transfer from subsidiaries to headquarters in the top Oil & Gas companies in Central and Eastern Europe as their level of innovations, internationalization and economic importance are emerging. The paper sheds a light not only on the process of knowledge transfer parent-subsidiary but via versa as it is critical in the 21st century for better adapting to specific business needs in certain geographical regions. Thus, this reversed knowledge from subsidiaries to headquarters is critical for the given business sector where the level of innovation and amount of R&D investments are enormous. The study argues that the reversed process of knowledge transfers from subsidiary to parent company is positively related to company performance and business diversification. Nowadays the knowledge formed in the subsidiaries of Multinational Corporations (MNCs) is transferred to headquarters by investing in R&D centres, building new exploration and testing sites abroad. In the reversed knowledge transfer process we can identify main challenges, which are very critical to analyse and determine the exact process.
New records of Aparasphenodon bokermanni (Pombal, 1993) from Santa Catarina, southern Brazil, and extension of genus range (Anura: Hylidae)
Authors: Zanette-Silva Larissa , Farias Douglas Lemos , Ghizoni-Jr Ivo Rohling
Published: December 2016

Aparasphenodon bokermanni is a poorly known casque-headed tree frog found in São Paulo and Santa Catarina, southern Brazil. Here we provide two new records, one from Joinville, northeastern Santa Catarina, and the first record from Santa Catarina Island, Brazil, which extends to the south the range of the genus by approximately 150 km.
UNA REFLEXION DE LA RELACIÓN: EDUCACIÓN, ECONOMÍA Y DESEQUILIBRIO AMBIENTAL
Authors: Celis Salazar Olga Lucia
Published: December 2016

Introducción: En el presente artículo se realiza una reflexión sobrecomo el ser humano ha usado ilimitadamente su pensamiento racionalpara producir ciencia y resolver problemas que le permitieron avanzarcientíficamente y distancio sus dimensiones estéticas, éticas, emocionales y de entorno generando consecuencias nefastas como planeta porejemplo con las plantas nucleares. Se teje una relación con el sistemaeducativo para pensar la educación desde una mirada ambiental y espiritual como lo están desarrollando científicos como Capra, Boff entremuchos otros que han venido estudiando el tema. En ese sentido, se hahecho necesario enmarcar la educación en un ambiente para la vida; enla tarea grande que involucre Educación para lograr que comunidadesaprendientes tengan un gran desarrollo social y político apoyado en elbienestar de todas las especies y la protección de Gaia, la gran Madre.
THE RESEARCH OF THE AMOUNT OF HEAVY METALS AND NITROSO COMPOUNDS IN CONCENTRATED TOMATO PRODUCTS
Authors: Shutyuk V.V.
Published: December 2016

The constant selling race results in need for improving the quality of nutrition products among in-house food and pharmaceutical processing industries, which is an all-important key to success on the consumer market. This requires constant improvement of the product producing technologies. The topical problem of quality is the presence of heavy metals and nitroso compounds in the products. The research aimed at studying the changes in the heavy metal concentration levels (including Zn, Cu, Pb) in tomato products at their thickening has been conducted at the national University of Food Technologies. On the basis of the received results the relationship between the lead, copper, zinc, nitrosocompounds and the solid substances’ amount has been established. The conducted research allowed us to ascertain the fact that the amount of heavy metals and nitroso compounds in raw materials for the concentrated tomato products to be ofhigh quality must not exceed the values of 18…35 % of the limiting concentration.
Development of formulation multicomponent protein-fat emulsion
Authors: Kotlyar Y. , Goncharenko Т. , Topchiy O.
Published: December 2016

The article is based on research of the protein components of different nature analysis. The possibility of their use as components of protein and fat emulsions for the purpose of modeling their optimal formulations for use in the composition of meat pates was proved. Rational individuals’ emulsification process parameters, which guarantee high-quality homogeneous emulsions, were found. The samples of protein and fat emulsions using protein drugs and partial replacement of animal fats fortified blend of vegetable oils, determined by their biological value, rheological, functional and technological properties were investigated. Organoleptic analysis model of meat pates masses were analyzed and recommended percentage of protein and fat emulsions on recipes meat pates are shown.
Technological characteristics of yeast-containing cakes production using waxy wheat flour
Authors: Iorgachova K. , Makarova O. , Khvostenko K.
Published: December 2016

This article shows the feasibility of using waxy wheat flour, the starch of which doesn`t contain amylose, in order to stabilize the quality of yeast-containing cakes. The influence of the waxy wheat flour mass fraction and the stage of its adding on the physical, chemical and organoleptic characteristics of the products are studied. According to the technological properties of a new type of wheat flour, two methods of its adding are proposed ‒ adding the maximum amount of waxy wheat flour at dough kneading stage or using the mixture of waxy and bakery wheat flours for kneading sourdough and dough. It is shown that the replacement of 60 % bakery wheat flour with waxy wheat flour in the recipe of yeast-containing cakes at the dough kneading stage contributes to the production of products with higher quality and organoleptic characteristics compared to both the control and cakes based on a mixture of different types of wheat flour. These samples are characterized by increased by 1.7 – 11.3 % specific volume, porosity – 2.6 – 5.5 % and the total deformation of the crumb – 6.5 – 41.4 %.
Зміна якісних характеристик пряників під час зберігання
Authors: Кравченко М.Ф. , Ярошенко Н. Ю
Published: December 2016

У статті наведено результати досліджень використання в пряниках нетрадиційних рецептурних компонентів: кедрового, кунжутного борошна та борошна з коріння гірчака зміїного. Проведено дослідження динаміки зміни фізико-хімічних, структурно-механічних, органолептичних показників пряників під час зберігання. Встановлено, що внесення рослинних добавок сприяє зниженню інтенсивності втрат вологи протягом досліджуваного терміну. Проведено дослідження залежності граничного напруження зсуву пряників від вмісту рослинних добавок. Побудовано профілі органолептичної оцінки якості пряників, де у вигляді фіксованої площі візуально підкреслено загальну величину кожного з органолептичних показників.
MODELING OF TEMPERATURE FIELDS IN A SOLID HEAT ACCUMULLATORS
Authors: Belimenko S. S. , Ishchenko V. O. , Gabrinets V. O.
Published: December 2016

Purpose. Currently, one of the priorities of energy conservation is a cost savings for heating in commercial and residential buildings by the stored thermal energy during the night and its return in the daytime. Economic effect is achieved due to the difference in tariffs for the cost of electricity in the daytime and at night. One of the most common types of devices that allow accumulating and giving the resulting heat are solid heat accumulators. The main purpose of the work: 1) software development for the calculation of the temperature field of a flat solid heat accumulator, working due to the heat energy accumulation in the volume of thermal storage material without phase transition; 2) determination the temperature distribution in its volumes at convective heat transfer. Methodology. To achieve the study objectives a heat transfer theory and Laplace integral transform were used. On its base the problems of determining the temperature fields in the channels of heat accumulators, having different cross-sectional shapes were solved. Findings. Authors have developed the method of calculation and obtained solutions for the determination of temperature fields in channels of the solid heat accumulator in conditions of convective heat transfer. Temperature fields over length and thickness of channels were investigated. Experimental studies on physical models and industrial equipment were conducted. Originality. For the first time the technique of calculating the temperature field in the channels of different cross-section for the solid heat accumulator in the charging and discharging modes was proposed. The calculation results are confirmed by experimental research. Practical value. The proposed technique is used in the design of solid heat accumulators of different power as well as full-scale production of them was organized.
CALCULATION OF CHARACTERISTICS OF STIFFNESS AND ELASTICITY OF RAIL THREADS WHEN TORSION UNDER COMBINED ACTION OF VERTICAL AND HORIZONTAL FORCES
Authors: Danilenko E. I.
Published: December 2016

Purpose. Reference data in technical literature about such characteristics as stiffness and elasticity of rail threads at torsion are rather contradictory. This is due to the absence of correct analytical solution of this task and because of complexity of experimental studies of this problem under combined action of vertical and horizontal lateral forces. The article presents the new method of solving the task of calculation the real values of stiffness and elasticity modules of rail thread when torsion under combined action of vertical and horizontal lateral forces. Methodology. The complex method of solving the problem was used in the paper. It includes the theoretical part and the results of the experiment. Using the experiment the characteristics of horizontal lateral stiffness of the rail threads of the head and bottom at different constructions of the modern rail fastenings was measured. The second task of determination of the real values of elasticity  and stiffness  modulus of the rail thread when torsion was solved by the theoretical methods. Findings. New values of stiffness characteristics and elasticity module of rail thread when torsion for the modern rail constrictions Р65, UIC60, Р50 and the rail fastenings of the types КПП, КБ, ДО, under combined action of vertical and horizontal forces and torsion were obtained. Originality. For the first time in domestic research it was carried out the experimental and theoretical solution of the task for determination of the real values of the stiffness and elasticity modulus of rail thread when torsion under combined action of vertical and horizontal forces of the wheel loadings. The solution is represented in the functional dependence on the correlation of vertical and horizontal forces ;  acting together. The solution is carried out for the modern designs of the rails of domestic standard P65, P50, P43 and international standard UIC60. Practical value. The obtained results make it possible to carry out calculations of the real acting strains and deformations in the rails of different types under the joint action of vertical and horizontal forces for railway track on concrete and wooden sleepers with different designs of rigid and elastic rail fastenings КБ, КПП, Д0 with higher accuracy as compared to the current calculation methodology.
INVESTIGATION OF AERODYNAMIC PRESSURE DURING THE HIGH-SPEED TRAIN PASSAGE
Authors: Djabbarov S. T.
Published: December 2016

Purpose. The scientific paper highlights research of aerodynamic pressure and distribution of airflow velocity field along the moving high-speed train. Methodology. The study of velocity field distribution around the moving high-speed train is produced by simulating its movement as axially symmetric body with the ogive-shaped head and tail parts in compressible (acoustic) environment. Findings. The values of the absolute velocity (theoretical) of air flow generated by the body movement is determined (for the case when the body moves at a constant speed (200, 250, 350, 400 km / h) at a certain height from the ground), for the points located at different distances from the axis of the moving body (high-speed train). The calculations results allowed building the graphs of the air flow velocity in the acoustic environment along the moving body at different distances from it. Using the Bernoulli law (pressure change dependences on the flow velocity), the values of the overpressure generated by the air stream from the moving body were determined. Originality. This is the first theoretical study of the aerodynamics of the high-speed train as axially symmetric body with the ogive-shaped head and tail parts in compressible (acoustic) environment, moving with steady speed. The research results allow us to establish the distribution of the excess air flow pressure generated along the moving high-speed train. Practical value. The obtained results allows determining of the following parameters: 1) requirements for physical-mechanical and strength characteristics of the individual elements of the railway infrastructure in the areas of high-speed train movement, subject to aerodynamic pressure; 2) minimum distance from the track safe for people location during high-speed train passage.
USE OF MICROCONTROLLER FOR MEASURING SHAFT SPEED OF DIESEL LOCOMOTIVE HYDRAULIC TRANSMISSION
Authors: Zhukovytskyy I. V. , Kliushnyk I. A.
Published: December 2016

Purpose. The article considers the process of development and improvement of tachometer data collectors for the data-measuring diesel locomotive hydraulic transmission test system, which will give the possibility of obtaining the source data to conduct further studies of the technical condition of diesel locomotive hydraulic transmission. It is supposed to provide a solution to the problem of development and improvement of tachometer data measuring tools of the previously created data-measuring diesel locomotive hydraulic transmission test system, starting out from the possibility of modification of the existing locomotive hydraulic transmission test-bench at the Dnepropetrovsk Diesel Locomotive Repair Plant «Promteplovoz». Methodology. The researchers proposed in the work a method of modifying the existing tachometer sensor of the automated microprocessor system for the locomotive hydraulic transmission test-bench in the conditions of a diesel locomotive repair plant. It is applicable by substantiating the choice of the required tachometer sensor measuring method, as well as by using the necessary hardware and software to accomplish the goal with the ability to integrate into the data-measuring system for diesel locomotive hydraulic transmission testing. Findings. The available equipment of the locomotive hydraulic transmission test-bench allowed for design of the optical type speed sensor based on the existing sensor D-2MMU-2. The factory testing with the use of a sensor prototype resulted in determination of the required and sufficient sampling time for sensor operating microcontroller. Originality. The available equipment of the locomotive hydraulic transmission test-bench allowed for design of the optical type speed sensor based on the existing sensor D-2MMU-2. We developed the operation algorithms for the microcontroller that processes the signals from this sensor. The sensor was factory-tested. According to the data sample obtained during the tests, we showed the possibility of reducing the sensor information retrieval frequency. Practical value. The designed sensor significantly reduces the cost of development of the diesel locomotive hydraulic transmission test-bench, besides it can be used when developing similar hydraulic transmission test-benches of other wheeled vehicles and the like. The designed sensor has a greater accuracy than that of D-2-2MMU and considerably lower production cost in comparison with current tachometer sensors. The measurement results are input data to perform further studies in order to determine the technical condition of UGP750-1200 hydraulic transmission during the factory post-repair testing.
THE BASIS OF MATHEMATICAL DESCRIPTION FOR WAVE MODEL OF STRESSES PROPAGATION IN RAILWAY TRACK
Authors: Kurhan D. M.
Published: December 2016

Purpose. Modern scientific research has repeatedly cited practical examples of the dynamic effects of railway track operation that go beyond the static calculation schemes. For the track sections where the train speed is approaching to the velocity of wave propagation in the slab track layers such issues are of particular relevance. An adequate tool for the study of such issues can be the use of the wave theory of stress propagation. The purpose of the article is the creation of a mathematical description of the basic principles of the stress propagation wave model in the railway track, which can be used as a basis for the practical development of the relevant calculation system. Methodology. The model of stress-strain states of the railway track on the basis of the stress wave propagation theory is to bring together the equations of the geometry of the outline of the space systems that is involved in the interaction at a given time, and the dynamic equilibrium equations of deformation. The solution is based on the use of the laws of the theory of elasticity. The wave front is described by an ellipsoid equation. When determining the variation in time of the surface position of the ellipsoid a vector approach is used. Findings. The geometry equations of the wave motion determine the volumes of material layers of the slab track involved in the interaction at a given time. The dynamic equilibrium determination of the deformed condition of the space bounded by the wave front makes it possible to calculate both the stresses and strains, and their changes during the time of the load perception. Thus, mathematical descriptions of the processes that occur in the perception of the load by the elements of railway track at high speeds were obtained. Originality. The simulation tasks of the track and rolling stock interaction, in particular taking into account the dynamic deflection of slab track were further developed. For the first time the article presents the basics of the mathematical description of the wave stress propagation model in the railroad track, which can be used to perform practical calculations. Practical value. The obtained data can be used to justify the track construction or establishing appropriate values of permissible speeds for the introduction of train motion with high speeds.
TERMS OF ENSURING QUALITY OF THE RAILWAY WHEELS BUILT UP BY WELDING
Authors: Haivoronskyi O. A.
Published: December 2016

Purpose. The paper assumes to set the basic laws in determining the structure and physical-mechanical properties of wheel steels during arc welding technology and to develop the recommendations for reconstruction of railway wheel wear surfaces that will improve the reliability and safety of traffic in terms of increasing operating loads. Methodology. To achieve this purpose the paper studied 1) the influence of operating loads on structural changes and properties of metal wheels; 2) the impact of arc welding on structural and phase composition and properties of the metal heat-affected zone, its resistance to brittle and slow fracture; 3) the impact of welded metal on the formation of the stress state of the welds and their resistance to formation cracks; 4) wear resistance of built up metal during friction-slip of the «wheel-rail» pair. Findings. The most intense zone of the rolling profile of freight railway wheels during operation is a place of transition from rolling surface to the ridge. Therefore, the wheel building up by welding requires first of all the increased resistance to brittle fracture of metal in this area. It is established that welding in the metal of the wheel heat-affected zone cause formation of the hardened bainite-martensite structures. The minimum metal cooling rate, at which the martensite start forming is 8°C / s (in the range of 600…500°C) when the content of carbon in steel is 0.58% and 2°C/s at 0.65% of carbon. It is shown that to increase resistance to cracking it is necessary to limit the cooling rate to 16.0°C/s when the carbon content is C < 0.60% and to 8.0°C / s when C = 0.60…0.65%. Under these conditions, the metal has rather high ability to mikroplastic deformation without cracking. It was founded that to improve the critical stress intensity factor К1С at brittle fracture it is necessary to provide conditions when welding would result in the built up structure that does not contain upper bainite and the martensite share does not exceed the number of lower bainite (ratio of M/Bn < 1). It is proved that exposure of wheels within 3.5-4.5 hours at 100°C after welding, during their slow cooling improves resistance to brittle fracture of metal heat-affected zone by 1.8-2.3 times. This is due to the removal of diffusion hydrogen from the metal and reduction of the ІІ type stress in the lath volume of bainite and martensite by 1.5. Originality. The author has developed the idea of the structural-phase changes that occur in the metal of railway wheels during arc welding. The relation between the carbon content in steel, cooling rate during welding and resistance to cracking and brittle fracture was found. The authors determined the influence of after-welding wheel cooling conditions on the metal properties. Practical value. Technological recommendations for railway freight wheel building up by welding were developed. Their application will improve quality of the railway wheels built up by welding, reliability and safety of traffic in conditions of growing operating loads.
PROBABILISTIC-PHYSICAL APPROACH TO DESCRIBE AND DETERMINE THE RELIABILITY OF CARS
Authors: Muradian L. A.
Published: December 2016

Purpose. The article aims to develop an algorithm and a sequence of description and determination of car reliability to predict certain quantitative indicators of the studied elements, parts and units, or a car as a whole on the basis of probabilistic-physical approach. Methodology. For the calculation of the indicators of reliability, durability and safety of cars the probabilistic-physical method was used, which takes into account the resources consumption inevitable in the operation of cars. The methodology of quantifying the reliability is based on the study of the physical-mechanical and physical-chemical properties and parameters of various elements, with the identification of principles of the aging processes of the elements or parts (with operating time) to determine the analytical dependencies of these processes from the indicators of cars reliability. Findings. On the basis of probabilistic-physical approach it was developed a model to describe and determine the reliability of the cars. At this the method of calculation based on probabilistic-physical model is fundamentally different from all known rigorous probabilistic methods by the fact that it considers a continuous set of states of the elements, parts and systems of the car during continuous time. If there exists or (if it possible to find) the information parameter about the resource consumption of the car element with evaluation of its change speed, and knowing its limit, based on the built car reliability model with the involvement of probabilistic-physical approach, one can predict all the necessary quantitative indicators of reliability of the studied elements, parts and units or a car as a whole. Originality. The methodology of the reliability construction with the use of probabilistic-physical model with DN-distribution was further developed in the article. The specific physical interpretation of the constants of DN-distribution of failures makes it possible to evaluate them according to the results of the study of certain parameters characterizing the technical condition of the car. On the basis of probabilistic-physical approach the algorithm and the sequence of description and determination of cars reliability to predict certain quantitative reliability indicators of the studied elements, parts and units, or a car as a whole were developed. Practical value. The results make it possible to calculate in practice the quantitative indicators of reliability of cars or their individual elements for further prediction of the overall reliability during operation.
FEATURES OF DRILLING-AND-BLASTING AT CONSTRUCTION OF BESKIDSKIY TUNNEL
Authors: Petrenko V. D. , Tiutkin O. L. , Proskurnia S. T.
Published: December 2016

Purpose. In this article it is necessary to analyze the possibility of developing technology and increasing its efficiency during the Beskidskiy tunnel construction in difficult engineering and geological conditions. Methodology. The authors have performed analysis of the technological level of mining and construction works, new technique, equipment and production. One of the important issues of blasting operation is to ensure the seismic safety, acting at a distance of 30 m in the axes of single-track tunnel, as the distance to it will be 20 m from the nearest charge in the laying tunnel. This problem was solved by applying the combined blasting of blast-hole charges with delay-action and long-delay ways. Herewith the total mass of charges in the stope was divided into three groups, in which the first group is exploded by short-delay firing with, and the second one is exploded by short-delay firing too with intervals of 200…400 ms, the third is exploded by long-delay blasting at intervals of 500…10000 ms. The combined blasting of short-delay charges and delay action ones let significantly reduce seismic action at a mass explosion of charges when driving of double-track railway tunnel of a large cross-section. Findings. The paper presents the developed technology model, describing dependence of the machines from engineering and geological conditions. The methodology of drilling and blasting works at the construction of the tunnel callote and stross as well as a technique of arrangement determination and intervals of shot-delay and delay blasting of blasthole explosive charges was developed. Maximum permissible concentration of gases and vapours at blasting was presented. The calculations showed that the maximum level of gas contamination of the working area in Beskidskiy tunnel is achieved at blast operations. In accordance with this ventilation of the tunnel when driving is carried out by independent systems with mechanical ventilation by blowing using mine fans of special mining enterprises. Originality. The developed seismically safety charge masses are based on the well-known state about antiseismic blasting regulations. Practical value. The authors proposed and grounded the efficient technology for reduction to practice of drilling and blasting works (with dividing of the tunnel cross-section into the calotte and stross during of the Beskydy high-mountain tunnel construction. The results of technological experiment are presented.
In Search of Lost Profiles: The Reliability of VKontakte Data and Its Importance for Educational Research
Authors: Smirnov Ivan , Sivak Elizaveta , Kozmina Yana
Published: December 2016

The potential of VKontakte as a data source is now acknowledged in educational research, but little is known about the reliability of data obtained from this social network and about its sampling bias. Our article investigates the reliability of VK data, using the examples of a secondary school (766 students) and a university (15,757 students). We describe the procedure of matching V K profiles to real students. A direct comparison permitted us to identify profiles of around 18% of students. A special technique introduced in the article increased this number up to 88% for school students and up to 93% for university students. We compare age, gender and GPA of identified students and those whomwe did not find on V K. We also compare the structure of social relationships, retrieved from VK data, to the expected structure of students’ social ties. We found that the structure of ‘virtual’ social relationships reproduces both the socio-demographic division of students into classes or majors andthe spatial division into different school buildings or university campuses. To our knowledge, it is the first study of this kind and scale based on VK data. It contributes to the understanding of how reliable data from this SNS is, how its accuracy can be improved, and how it can be used in educational research.
New Trends in School Education Development. Based on the Annual Monitoring Research Conducted by the Center of Economy of Continuous Education of the Presidential Academy of National Economy and Public Administration (RANEPA)
Authors: Avraamova Elena , Loginov Dmitry
Published: December 2016

We analyze results of the fourth wave of the annual monitoring of school effectiveness conducted by the Center of Economy of Continuous Education of the Presidential Academy of National Economy and Public Administration (RANEPA) since the academic year 2012/13. Based on a survey of school principals, teachers and parents, we build quite a holistic picture of school education evolution and changes to its components, such as staffing of school, teaching quality, as well as professionalism, salaries and social positions of teachers. The development of the school education system from the perspective of principals and teachers is compared to the parental requirements for school education. We also show the effects of the downturn economy on education, in particular the cuts to school funding. Teachers report a decrease in their salaries. Egalitarian distribution of incentive bonuses has given way to a higher differentiation in payment of teachers, which can be regarded as a positive effect of the efficient contract. The reduced effective demand for supplementary educational services entails a decline in extrabudgetary revenues. There has been a perceptible decrease in the territorial differentiation of payment of teachers, teacher engagement in advanced training programs, and the quality of education as such. At the same time, regional differentiation is growing. The chain of transformations launched by the remuneration reform has rejuvenated the staff composition of Russian schools, enhanced the quality of the teaching staff, and contributed to better interaction between teachers and other school education actors, but have not yet told on the quality of graduates.
The Structure of Students’ Motivation: Expectancies and Values in Taking Data Science Course
Authors: Ivaniushina Valeria , Alexandrov Daniil , Musabirov Ilya
Published: December 2016

In this paper we explore motivational structure of students taking a challenging university course. The participants were second-year undergraduate students majoring in Economics, Sociology, Management and Humanities, enrolled in the Data Science minor. Using expectancy-value theory as a framework, we aim (1) to analyze gender differences in motivation; (2) to identify the link between the components of motivation and academic achievement; (3) to estimate the role of the previous academic achievement and educational choices. Two alternativetheoretical models are proposed and tested on empirical data. Structural equation modeling (SEM) in M Plus 7.31 was used for analysis. We found that the course is more popular among males students, who also demonstrate higher level of expectancy for success. However, there is no gender difference in academic performance. Students majoring in Sociology and Economics perceive Data Science as more interesting and useful than Management and Humanities students. SEM analysis empirically validated the model in which expectancy of success directly influences academic achievement, and values influence is mediated by expectancies. The final model that includes motivation, gender, student’s major, and previous achievement explains 34% of variance in academic performance. We discuss the role of different components of student motivation and practical significance of our results.