bluuebunny/crossref_metadata_2025 huggingface dataset:
The Role of Effortful Control in Stuttering Severity in Children: Replication Study
Authors: Kraft Shelly Jo , Lowther Emily , Beilby Janet
Published: December 2018

Background

In 2014, Kraft et al. assessed the temperament, home environment, and significant life events of 69 North American children who stutter to examine the combined and compounded effects of these individualized factors on mediating overt stuttering severity. The temperament domain of effortful control was singularly found to be significantly predictive of stuttering severity.

Purpose

Because of the clinical significance of the initial study's findings, a replication study with a different, larger cohort of children who stutter was warranted to validate the reported outcomes.

Method

The current study assesses 98 children who stutter, ages 2;4 to 12;6 (years; months,
M
= 6;7), recruited from Perth, Australia.

Results

The results support the previous findings of
Kraft, Ambrose, and Chon (2014)
, with effortful control remaining the sole significant contributor to variability in stuttering severity, as rated by both parents and clinicians.

Conclusion

These cumulative and consistent outcomes support the need to develop targeted intervention strategies that specifically strengthen aspects of effortful control as a means to support positive therapeutic change in children who stutter.
Estimates of the Prevalence of Speech and Motor Speech Disorders in Youth With 22q11.2 Deletion Syndrome
Authors: Baylis Adriane L. , Shriberg Lawrence D.
Published: December 2018

Purpose

Speech sound disorders and velopharyngeal dysfunction are frequent features of 22q11.2 deletion syndrome (22q). We report the first estimate of the prevalence of motor speech disorders (MSDs) in youth with 22q.

Method

Seventeen children and adolescents with 22q completed an assessment protocol that included a conversational speech sample. Data reduction included phonetic transcription, perceptual speech ratings, prosody-voice coding, and acoustic analyses. Data analyses included 3 motor speech measures and a cross-classification analytic. Prevalence estimates of speech and MSDs in youth with 22q were compared with estimates in speakers with other complex neurodevelopmental disorders: Down syndrome, fragile X syndrome, and galactosemia.

Results

Results indicated that 58.8% of the participants with 22q met criteria for speech delay, and 82.4% of the participants met criteria for MSDs, including 29.4% with speech motor delay, 29.4% with childhood dysarthria, 11.8% with childhood apraxia of speech, and 11.8% with concurrent childhood dysarthria and childhood apraxia of speech. MSDs were not significantly associated with velopharyngeal dysfunction.

Conclusions

In summary, 82.4% of the participants with 22q met criteria for 1 of 4 MSDs, predominantly speech motor delay and childhood dysarthria. Cross-validation of the present findings would support viewing MSDs as a core phenotypic feature of 22q.
The Effects of Speech Compression Algorithms on the Intelligibility of Two Individuals With Dysarthric Speech
Authors: Utianski Rene L. , Sandoval Steven , Berisha Visar , Lansford Kaitlin L. , Liss Julie M.
Published: December 2018

Purpose

Telemedicine, used to offset disparities in access to speech-language therapy, relies on technology that utilizes compression algorithms to transmit signals efficiently. These algorithms have been thoroughly evaluated on healthy speech; however, the effects of compression algorithms on the intelligibility of disordered speech have not been adequately explored.

Method

This case study assessed acoustic and perceptual effects of resampling and speech compression (i.e., transcoding) on the speech of 2 individuals with dysarthria. Forced-choice vowel identification and transcription tasks were utilized, completed by 20 naive undergraduate listeners.

Results

Results showed relative improvements and decrements in intelligibility, on various measures, based on the speakers' acoustic profiles. The transcoding of the speech compression algorithm resulted in an enlarged vowel space area and associated improvements in vowel identification for 1 speaker and a smaller vowel space area and decreased vowel identification for the other speaker. Interestingly, there was an overall decrease in intelligibility in the transcription task in this condition for both speakers.

Conclusions

There is a complex interplay between dysarthria and compression algorithms that warrants further exploration. The findings suggest that it is critical to be mindful of apparent changes in intelligibility secondary to compression algorithms necessary for practicing telemedicine.

Supplemental Material

https://doi.org/10.23641/asha.7291940
An Eye-Tracking Study of Receptive Verb Knowledge in Toddlers
Authors: Valleau Matthew James , Konishi Haruka , Golinkoff Roberta Michnick , Hirsh-Pasek Kathy , Arunachalam Sudha
Published: December 2018

Purpose

We examined receptive verb knowledge in 22- to 24-month-old toddlers with a dynamic video eye-tracking test. The primary goal of the study was to examine the utility of eye-gaze measures that are commonly used to study noun knowledge for studying verb knowledge.

Method

Forty typically developing toddlers participated. They viewed 2 videos side by side (e.g., girl clapping, same girl stretching) and were asked to find one of them (e.g., “Where is she clapping?”). Their eye-gaze, recorded by a Tobii T60XL eye-tracking system, was analyzed as a measure of their knowledge of the verb meanings. Noun trials were included as controls. We examined correlations between eye-gaze measures and score on the MacArthur–Bates Communicative Development Inventories (CDI; Fenson et al., 1994), a standard parent report measure of expressive vocabulary to see how well various eye-gaze measures predicted CDI score.

Results

A common measure of knowledge—a 15% increase in looking time to the target video from a baseline phase to the test phase—did correlate with CDI score but operationalized differently for verbs than for nouns. A 2nd common measure, latency of 1st look to the target, correlated with CDI score for nouns, as in previous work, but did not for verbs. A 3rd measure, fixation density, correlated for both nouns and verbs, although the correlation went in different directions.

Conclusions

The dynamic nature of videos depicting verb knowledge results in differences in eye-gaze as compared to static images depicting nouns. An eye-tracking assessment of verb knowledge is worthwhile to develop. However, the particular dependent measures used may be different than those used for static images and nouns.
Language Skill Mediates the Relationship Between Language Load and Articulatory Variability in Children With Language and Speech Sound Disorders
Authors: Vuolo Janet , Goffman Lisa
Published: December 2018

Purpose

The aim of the study was to investigate the relationship between language load and articulatory variability in children with language and speech sound disorders, including childhood apraxia of speech.

Method

Forty-six children, ages 48–92 months, participated in the current study, including children with speech sound disorder, developmental language disorder (aka specific language impairment), childhood apraxia of speech, and typical development. Children imitated (low language load task) then retrieved (high language load task) agent + action phrases. Articulatory variability was quantified using speech kinematics. We assessed language status and speech status (typical vs. impaired) in relation to articulatory variability.

Results

All children showed increased articulatory variability in the retrieval task compared with the imitation task. However, only children with language impairment showed a disproportionate increase in articulatory variability in the retrieval task relative to peers with typical language skills.

Conclusion

Higher-level language processes affect lower-level speech motor control processes, and this relationship appears to be more strongly mediated by language than speech skill.
InAs‐based quantum cascade lasers emitting close to 25 µm
Authors: Loghmari Z. , Bahriz M. , Meguekam A. , Teissier R. , Baranov A.N.
Published: December 2018

Indium arsenide (InAs)‐based quantum cascade lasers (QCLs) operating close to 25 µm are reported. Thick n‐doped InAs cladding layers were used for optical confinement. Fabry–Perot lasers exhibited a threshold current density as low as 1.1 kA/cm2 in pulsed mode at 80 K. The lasers operated in this regime up to 240 K, where the threshold current density increased up to 1.7 kA/cm2. These are the lowest threshold current densities for QCLs operating above 20 µm.
Reweighted nuclear norm minimisation for DOA estimation with unknown mutual coupling
Authors: Meng Dandan , Wang Xianpeng , Huang Mengxing , Yin Yue , Shen Chong , Zhang Kun
Published: December 2018

A reweighted nuclear norm minimisation algorithm by considering the inherent rank sparsity of the submatrix block for direction‐of‐arrival (DOA) estimation with unknown mutual coupling in a uniform linear array (ULA) is proposed. A novel block overcomplete dictionary is first derived by parameterising the steering vector to avoid the unknown mutual coupling effect. Then, in order to take advantage of the inherent rank sparsity of the submatrix block, a reweighted nuclear norm minimisation algorithm is introduced, and the weighted matrix can be designed by the Capon spectrum for enhancing the sparsity of scheme. Finally, the DOA estimates can be obtained by the spatial spectrum of the reconstructed matrix. Simulation results verify that the proposed method has distinct advantages over state‐of‐the‐art methods.
Monopulse antenna‐pointing system modelling and simulation
Authors: Latifzade Mohammad Ali , Arvan Mohammad Reza , Mohseni Armaki Hosein
Published: December 2018

Mahdasht Satellite Receiving Station (MSRS) has been using 10 m reflector antenna to communicate with LEO satellite at S‐band (2.2–2.3 GHz) and X‐band (8–8.4 GHz). Presently, antenna pointing operates in program tracking. Pointing accuracy under program tracking conditions is in the neighbourhood of 0.2°. This is acceptable at S‐band, but not enough at X‐band. Due to the narrow beamwidth at X‐band, it is important to improve pointing accuracy significantly (0.05°). Monopulse antenna tracking is one approach that provides tracking accuracy at high‐frequency bands. This study presents mathematical model and simulation of monopulse pointing system using a novel analytic approach. Monopulse error signals are calculated using the proposed model while considering the kinematic equations with the assumption of the Gaussian radiation pattern for reflector antenna. The simulation results are verified by using a real (MSRS antenna) monopulse tracking system in X‐band frequency (8.2 GHz). The measurement and simulation results demonstrated the azimuth and elevation pointing errors are valid in 3 dB beamwidth.
Proposed 2D and 3D geometries intended for smart antenna applications, including direction finding and beamforming implementation
Authors: Poormohammad Sarah , Farzaneh Forouhar
Published: December 2018

Novel two‐dimensional (2D) and three‐dimensional (3D) antenna array geometries for smart antenna application are introduced. Minimum mean square error beamforming algorithm, using these arrays, in presence of signal, noise and interferences is implemented. Beamforming approach is used for every type of array assuming uniform and log‐normal distributions for the interference amplitudes. Equal volume cylindrical or prism type arrays with circular, hexagonal, triangular, square and star cross‐sections with equal number of elements are considered. Novel geometries consisting of rotated cross‐sections are studied as well. In each case, the relative signal‐to‐interference ratios (SIRs) are compared in these geometries, showing that the triangular and the star cross‐section prisms have a better performance with respect to other cylindrical geometries. Monte‐Carlo simulations show that the rotated geometries have better performance than the conventional 3D geometries both in terms of direction finding resolution and SIR values. Given the performance evaluation of these arrays in terms of direction finding resolution and beamforming precision, smart antenna realisation becomes plausible with these novel geometries for practical purposes.
Online monitoring of transformer through stream clustering of partial discharge signals
Authors: Firuzi Keyvan , Vakilian Mehdi , Phung B.Toan , Blackburn Trevor
Published: December 2018

The general method for identifying the partial discharge type in a power transformer is based on their fingerprints in the form of phase‐resolved discharge patterns. In the case of multiple defects, traditional clustering methods can be applied for separation of active sources. However, such an approach is impractical for online real‐time monitoring due to the very large data size. In this paper a new method using stream clustering is introduced. The method separates the active sources by processing the signal once it is captured, then only a synopsis of the discharge data is stored. Two stream clustering algorithms: Density Grids and DenStream are employed. Through measurements obtained from laboratory experimental setups (corona, surface discharge, transformer defect model) performance of the proposed algorithms are evaluated. It is shown that stream clustering method is able to separate the constituent components involved in the stream of a multi‐source discharge signal without the need to store a large amount of information. The performance of the Density Grids method depends on a limited number of features that it can accommodate. In comparison, the DenStream method can capture more features which enable better separation of active sources at the expense of longer processing time.
Analysis of load of a powered roof support’s hydraulic leg
Authors: Szurgacz Dawid , Brodny Jarosław
Published: December 2018

The main purpose of the powered roof support is to protect headings from the impact of the rock mass. The result of such impact is static and dynamic load impacting the support section, which is carried by its construction. The basic elements of the construction of the support are hydraulic legs, whose task is to ensure adequate strength of its setting. Particularly in the case of dynamic impact of the rock mass, these legs are exposed to a very unfavourable load condition. Therefore, it is necessary to conduct tests to determine the parameters of operation for this type of loads. The paper presents the results of tests on the hydraulic leg subjected to impact load with free falling impact mass. The purpose of the research was to determine the parameters of the leg's operation, i.e. the time periods of pressure in the space under the piston and other elements of the hydraulic system. The tests were conducted in compliance with designed methodology and included innovative registration system. The obtained results clearly indicate the correctness of the adopted assumptions. According to the authors, the results should be applied during selection and operation of a powered roof support.
The analysis of atmospheric factors affecting the value of vertical refraction angle with the assessment of the importance of introduction of the atmospheric amendment
Authors: Kaczor Paulina
Published: December 2018

The study of vertical displacements of hydrotechnical objects, slender constructions, opencast mines or flotation waste reservoirs often requires continuous geodetic monitoring, which in real time defines potential threats resulting from changes in the geometry of the object. In order to ensure high accuracy in determining vertical displacements, a precise robotic tacheometer is used as one of the monitoring sensors. In the case of trigonometric leveling, the quality of measurements is affected not only by the accuracy of the instrument, but also by the centre through which the laser beam emitted by it passes. The radius emitted by the tacheometer due to the layered structure of the atmosphere is deflected, and the angle that it creates with the theoretical course of rays is called the angle of vertical refraction. In order to eliminate the influence of this type of errors, so-called atmospheric correction is introduced to all tacheometric measurements. Currently, total stations automatically determine and introduce corrections for observation, usually using only air temperature and atmospheric pressure. However, the number of factors responsible for the change in atmosphere density, and thus the deflection of the laser beam is much greater. And its influence is also affected by the length of the target and roughness of the area over which the measurement is made. The paper presents the analysis of the significance of various atmospheric and terrain factors that may affect the value of the vertical refraction angle. By the multiple regression method, with the use of the analyzed factors, equations describing the phenomenon of vertical refraction for four seasons have been designated. The defined equation coefficients were used to determine the refraction angle for the observations recorded on the post-flotation waste tank. To confirm the rightness of introducing an additional atmospheric correction, analyses were performed showing the percentage of corrected results.
Insulation Failure Prediction Model of Power Cable in Fire
Authors: Li Jin-mei , Zhang Jia-qing , Li Qiang , Ren Shi-jing
Published: December 2018

With input parameters being determined, simplified physical model and heat conduction equation were adopted to establish a power cable insulation failure prediction model in fire, and the validation test was carried out. The internal structure of the cable was simplified to a one-dimensional physical model with three layers, to derive the calculation method of internal structure parameters of cable physical model. Differential equation of heat conduction, which could reflect the internal temperature of cable, was constructed based on basic assumptions, to establish a cable insulation cable failure prediction model with mixed layer heat diffusion coefficient, environment temperature change and insulation cable failure temperature as input parameters. The method to determine model input parameters was also proposed. ZR-YJV and SDR-1 cable thermal radiation furnace were selected in the experiments to obtain insulation failure temperature and time, as well as environmental temperature change of the cable. The experimental results showed that the constructed model had relative small error in predicting cable insulation failure time.
Selection of a Remote Phosphor Structure for Phosphor-converted White LEDs with High Luminous Efficacy
Authors: Ngoc Long Nguyen , Anh Nguyen Doan Quoc , Hong Nhu Nguyen , Zdralek Jaroslav , Voznak Miroslav
Published: December 2018

This study presents the influence of the distance between phosphor layers in the dual-layer and triplelayer remote package on luminous efficacy. During the simulation, it is recognized that an appropriate distance can produce higher luminous flux of the multi-chip white LED (WLEDs) through adjusting the distance between two and three phosphor layers. According to the research results, 0.1 mm is the outstanding distance between two phosphor layers so that the performance of MCW-LEDs can be accomplished the best optimal effect. In addition, the simulation results show that the dual-layer structure yielded higher optical properties than the triple – layer structure in relation to the distance.
Torque Analysis of Scotch Yoke Type Hydraulic Actuator
Authors: Kim Sedong , Song Hee-Geun , Lee Dae-Chul , Lee Kwang-Bae , Jeong Hyomin
Published: December 2018

At present, hydraulic actuators have been strongly highlighted in the shipbuilding industrial applications. The actuators are classified into three types according to their operation, such as scotch yoke, rack and pinion, rod and crank type. However, hydraulic actuators are more difficult than others electric motors because of nonlinear flow-pressure characteristics and many cases of torque between moving parts. In this paper, in order to obtain the data of the valve locking torque value of the scotch yoke, the pressure was applied at a pressure of 6~16 MPa and analysis by depending on cylinder diameter and yoke length using ANSYS tool. According to the results of generating torque value, it is understood that the torque increases as the cylinder diameter increases and the moment arm becomes longer. It can be also seen that the all average error rates of experimental values and program analysis values are only under the 3%.
The priority classification method of mobile users under direct power transaction
Authors: Lei Wang , Chuncheng Gao , Qian Zhang , Yong Dai
Published: December 2018

With the development of mobile internet technology, market-oriented electricity reform forms a new transaction mode that "Internet + power trading", which further promotes the liberalization of retail side market. A large number of mobile power users actively participate in the electricity market transaction. However, the current standards for mobile users who are accessed to the market are qualitative standards, lacking of quantitative analysis. The priority classification method of mobile users under direct power transaction is proposed in the paper. First, the priority evaluation index set of mobile users is established from four dimensions that credit condition, environmental condition, power consumption condition and load importance to achieve evaluation quantitatively. Secondly, Kmeans clustering algorithm based on SOM is used to cluster mobile users. Finally, the paper recognizes the various types of mobile users as a whole and estimates their priorities using the improved AHP(Analytic Hierarchy Process).The method realizes the specific division of mobile users from a point of quantitative view, and solves the problem of only qualitative standard currently, to optimize the development of direct power transaction and promote the marketization of power market.
Simultaneous Determination of Three Effective Components in Different Compatibility Proportion of the Couple of Sophora flavescens-Fructus Ligustri lucidi by HPLC
Authors: Chu Shuhan , Zhang Hongxu , Ding Lixin
Published: December 2018

Sophora flavescens - Ligustrum lucidum has the effect of increasing the anti-cancer effect of white blood cells and treating liver fibrosis. In order to determine the optimal compatibility ratio of this drug pair, the rationality of the drug pairs in different proportions was revealed. In this experiment, three active ingredients of the Sophora flavescens-Fructus Ligustri lucidi were extracted by reflux extraction, which were matrine, oxymatrine and specnuezhenide. A method for simultaneously determining the content of matrine, oxymatrine and specnuezhenide in a short time by HPLC was established. The method is simple, precise, and stable. Reproducibility can be used to determine the content of three active ingredients of matrine, oxymatrineand specnuezhenide. The analysis results was indicated that the different proportions of compatibility and different extraction solvents have significant effects on the content of active ingredients and dissolution rate of Sophora flavescens- Fructus Ligustri lucidi, after the combination of Sophora flavescens- Fructus Ligustri lucidi in different proportions, the content of matrine, oxymatrine and specnuezhenide is greater than the content of the active ingredients of each single herb. When the ratio of compatibility of Sophora flavescens-Ligustrum Ligustri lucidi is <1:1, it is beneficial to the dissolution of the three active ingredients. By determining the optimal compatibility ratio of this drug pair, provided a theoretical basis for the study of late pharmacodynamics and provide theoretical basis for clinicalapplication of traditional Chinese medicine.
Peculiarities of the use of siliceous raw materials of the Russian Far East in the integrated pipeline protection
Authors: Yatsenko Elena A. , Goltsman Boris M. , Ryabova Anna V. , Smoliy Victoria A.
Published: December 2018

Modern trends in the development of Russian oil and gas infrastructure are examined. The important role of the Far East in the transportation and export of oil is revealed. The main threats in the operation of pipelines are described. The integrated protection technology of pipeline surfaces is proposed. The structure and properties of local silicate raw material – diatomite – are studied. The technology of obtaining glass enamel coating is designed to protect the internal surface of the pipe. The phase composition, microstructure and properties of the coating are compared with analogues. The technology of foam glass production is designed to protect the external surface of the pipe. The foaming processes are studied; the properties and structure of the material are examined. The optimum ratio of raw materials is revealed. Recommendations on the application of the developed technology for integrated pipeline protection are given.
The role of cavitation in submicron aerosol dispersion
Authors: Kudryashova Olga , Muravlev Evgeny , Vorozhtsov Boris , Akhmadeev Igor
Published: December 2018

Here we discuss the problem of atomizing submicron aerosols by special design atomizers enabling the cavitation regime. The formation of submicron aerosol was studied using an impulse atomizer model powered by a high-energy material and an atomizer model with a special spray nozzle generating countercurrent flows. For these atomizers, the role played by cavitation in producing submicron liquid aerosols is demonstrated herein. A mathematical model is also suggested to describe the aerosol cloud genesis. The cavitation development critical pressure, outflow velocity, and the resulting droplet sizes were evaluated. The aerosol particle size and concentration were experimentally measured by optical methods. The measured disperse parameters of aerosols during the origination and propagation of the aerosol cloud resulted from the cavitation-assisted atomization of liquids are reported: the intrinsic particle diameter of water aerosol is 10…30 μm depending on the features of the atomizer designs and their operating regimes.
Combustion peculiarities of coal-methane-air mixtures in a recuperative burner
Authors: Minkov Leonid , Moiseeva Kseniya
Published: December 2018

Numerical modeling of the combustion of a lean methane-air mixture containing fine coal particles entering the “Swiss-roll” type recuperative burner is considered. The mathematical model is constructed under the following assumptions: the flow field is two-dimensional; the gas mixture is an ideal incompressible gas consisting of oxygen, methane, coal volatile substances, carbon monoxide, carbon dioxide, water vapor, hydrogen and nitrogen. In the gas phase four oxidation reactions, in which methane, volatile matter of coal, carbon monoxide, hydrogen participate and the reaction of carbon dioxide decomposition take place. On the surface of the coal particle, there are three oxidation reactions involving oxygen, carbon dioxide and water vapor, resulting in the formation of carbon monoxide. It is assumed that coal contains 8% of ash, 12.9% of volatile substances and 79.1% of carbon. It is shown that for a two percent methane-air mixture the reaction zone shifts toward the center of the burner as the feed rate of the mixture increases. An increase in the content of coal particles leads to a shift of the reaction zone into the inlet part of the burner, and the heat release in the burner increases.
Mathematical modeling of plastic deformation of a tube from dispersion-hardened aluminum alloy
Authors: Matvienko Oleg , Daneyko Olga , Kovalevskaya Tatyana
Published: December 2018

The influence of the internal and external pressure subjected to the tube from dispersion-hardened aluminium alloy was investigated. The approach which combines methods of crystal plasticity and mechanics of deformable solid was used to explore the limits of elastic and plastic resistance. The mathematical model of plastic deformation includes balance equations for deformation defects with regard to the generation and annihilation of shear dislocations, vacancy and interstitial prismatic dislocation loops, and dislocations in dipole configurations of vacancy and interstitial types and also equilibrium equation, geometrical and physical relations between the deformations, displacements and stresses. It has been established that as the temperature increases, the limits of the elastic and plastic resistance decrease. Results of investigation demonstrate that the hardening the alloy by nanoparticles significantly improves the strength characteristics of the material.
Al-Ti-B4C materials obtained by high-temperature synthesis and used as a master-alloy for aluminum
Authors: Zhukov Ilya , Promakhov Vladimir , Dubkova Yana , Matveev Alexey , Ziatdinov Mansur , Zhukov Alexander
Published: December 2018

The paper presents microstructure, composition, and burning rate of Al alloy produced by high-temperature synthesis (SHS) from powder mixture Al-Ti-B4C with different concentration of Al powder. It has been established that the phase composition of materials obtained at gas-free combustion includes TiB2, Al, and TiC. It is shown that Al content growth powder in initial Al-Ti- B4C mixture from 7.5 to 40 wt.% reduces the burning rate of the powder from 9*10-3to 1.8*10-3m/s. For the system consisting of 60 wt.% of (Ti + B4C) and 40 wt.% of Al there is the increase in the porosity of the compacted initial powder mixture from 30 to 51 and reduction in the burning rate from 1.8 * 10-3to 1 * 10-3m/s. The introduction of 0.2 wt.% of the obtained SHS materials into the melt of pure aluminum causes reduction of the grain size of the resulting alloy from 1200 to 410 μm.
Structure feature of ternary state diagrams of Cr-Ti-V and Cr-Mn-V systems
Authors: Klopotov Anatoliy , Kurzina Irina , Potekaev Alexander , Ustinov Artem , Dement Taras , Kazantseva Ludmila , Marchenko Ekaterina , Karakchieva Natalia
Published: December 2018

This paper presents the research results of features of structural and phase states in Cr-Ti-V and Cr-Mn-V systems based on analysis of crystal-geometric and crystal-chemical factors. The diagrams of isothermal sections of state diagrams of Cr-Ti-V and Cr-Mn-V systems were built in coordinates of the electron number (s+d) per atom with homogeneity regions of solid solutions and intermetallic compounds. It was shown that in the Cr-Ti-V system, addition of Mn atoms leads to substantial extension of the existence domain of the disordered solid solution based on the BCC lattice.
Powders of metal borides obtained by the SHS method and low-temperature plasma
Authors: Zhukov Ilya , Vorozhtsov Alexander , Promakhov Vladimir , Dubkova Yana , Zhukov Alexander , Khrustalev Anton
Published: December 2018

This paper introduces principle possibility of producing aluminum and titanium boride predetermined morphology using the SHS method and plasma processing. Thermal analysis data for synthesized boride powders in comparison with boron powder and nano-sized aluminum are presented It was found that the synthesized metal borides, according to the thermal analysis data, are promising as a fuel in high-energy materials: the oxidation state of AlB2 is ~ 80%, at a degree of boron oxidation ~ 20%, aluminum ~ 67%.
Comparison of the mechanical properties and microstructural evolution in the HAZ of HSLA DOMEX 700MC welded by gas metal arc welding and electron beam welding
Authors: Kopas Peter , Sága Milan , Jambor Michal , Nový František , Trško Libor , Jakubovičová Lenka
Published: December 2018

High strength low alloyed steels are nowadays an important group of engineering materials, with numerous industrial applications. Properly chosen chemical composition together with the thermomechanical processing allow to reach high mechanical properties, while the carbon content is maintained low. Resulting microstructure is therefore sensitive to the amount of the heat introduced to the metal during welding. During welding procedure, softening phenomenon can occur in the heat affected zones and it could lead to the degradation of the mechanical properties of the final joint. Nowadays, welding technologies based on the high energy electron beam are able to produce weld joints with very narrow heat affected zone. In this study, authors compare mechanical properties and the microstructural evolution in the heat affected zone of the GMAW and EB welded joint of the DOMEX 700MC HSLA steel. The carried out experiments showed that both evaluated technologies are able to produce joints with appropriate mechanical properties. Welded joints made by the EBW technique showed slightly better mechanical properties of the whole joint, as a result of the narrower HAZ.
Static analysis of transmission tower beam structure
Authors: Jakubovičová Lenka , Sapietová Alžbeta , Moravec Jan
Published: December 2018

The main topic of this paper is a static analysis of transmission tower beam structure fixed to the earth. It contains facts necessary for a need to create and apply tower beam structures. Beam elements were used to design a model and a static analysis was performed in finite element program Ansys Workbench. Three types of analyses were applied. The modal analysis was applied to verify the model compatibility. The static analysis was applied to find maximal deformations and the bending moment caused by overhead conductors and self-weight. Eigenvalue buckling was applied to state a loss of stability. Finally, stability and suitability of the whole construction was considered.
Possibilities of using interlayers during diffusion welding of Ti Gr2 and AISI 316L
Authors: Moravec Jaromir , Novakova Iva , Kik Tomasz
Published: December 2018

Joining of materials with different physical and mechanical properties is always very problematic. As one of the possibilities, there can be used method of joint creation in solid state - e.g. by the diffusion welding. With this method it is possible to joint very different materials - even metals with non-metals. Despite the unquestionable advantages of this method, there is necessary to take into account also its limits. Among of them, there is creation of brittle intermetallic phases on the boundary of materials. This occurs e.g. at creation heterogeneous joints between titanium and highly-alloyed austenitic steel. The major aim of this paper is to describe how it is possible to eliminate brittle intermetallic phases created on boundary between Ti Grade 2 and AISI 316L steel by using metal interlayers.
Impact study of single stage and multi stage abrasive machining on static strength of lap adhesive joints of mild steel
Authors: Rudawska Anna , Miturska Izabela
Published: December 2018

The article presents the results of research on the influence of one of the technological factors, which is preparation of C45 steel surface before bonding. Seven methods of surface preparation performed by mechanical abrasive grinding tools of different gradations: P40, P120, P320 and P500 in various combinations one-stage or multi stage and degreasing were analysed. The obtained results were subjected to a statistical one-way analysis of variance, which proved that the strength of the adhesive joints depends on the appropriate choice of tools used for abrasive processing, while preparing the surface of the joints before bonding.
Use of high-speed water flows for accelerated mechanical modelling of erosive wear of concrete surfaces
Authors: Sitek Libor , Hlaváček Petr , Bodnárová Lenka
Published: December 2018

The article deals with an unconventional way of simulating the erosion of concrete surfaces by means of high-speed water flows. The proposed method allows the use of short-term experiments to predict the future failure of concrete elements in specific concrete mixtures exposed in practice to the action of fast-flowing fluids, whether as regards sewers, overfalls of water reservoirs, inlet channels of retention reservoirs, etc. The article shows results of experiments on disintegration of the surface layer of model concrete test specimens of various physical-mechanical properties that were exposed to various types of high-speed water flows. It has been demonstrated that the application of high-speed water flows significantly accelerates the degradation process of the surface layers. This simulation of the real situation can considerably shorten the time needed for the development and testing of new erosion-resistant construction elements.
Studies of thin-walled parts deformation by gripping force during turning process on an example of bearing ring
Authors: Patalas Adam , Regus Michał , Peta Katarzyna
Published: December 2018

In this paper thin-walled part deformation during finishing turning process caused by gripping force of hydraulic lathe chuck was investigated. Bearing ring was taken as an example of thin-walled part undergo finishing turning operation. Finite Element Method (FEM) was used to define the deformation of examined part. The aim of presented research was to compare the deformation of bearing ring caused by gripping force of hydraulic 3-jaw chuck and 6-jaw chuck for different values of total gripping force. The data obtained from conducted simulations allowed to evaluate the influence of gripping force on machining part deformation which is directly related with its geometrical accuracy.
Engine with unconventional crank mechanism FIK1
Authors: Kukuča Pavol , Barta Dalibor , Labuda Robert , Gechev Tsvetomir
Published: December 2018

The geometry and kinematics of unconventional engine mechanism FIK1 are described in the paper. Transformation of the piston linear movement to rotational movement is done by a swinging board, a baseboard and a crankshaft. The paper describes the trajectory and acceleration of an observed point on the swinging board in all three planes as well as the kinematics of the piston movement. The principle of the unconventional mechanism FIK1 is protected by patents No. 283742 and No. 283743. A mathematical model of the mechanism and some significant results are presented.
Non-destructive testing of automotive heat exchangers
Authors: Peta Katarzyna , Żurek Jan , Patalas Adam
Published: December 2018

The paper presents the results of non-destructive testing to the final control of automotive heat exchangers, which must meet a number of technological and exploitative requirements resulting from their working conditions. For the observation of images of heat exchangers, verification of geometrical dimensions and identification of surface and volume defects, the used methods were: computed tomography (highresolution microtomograph Phoenix v|tome|x), three-dimensional optical scanning (3D GOM ATOS III optical scanner), coordinate measuring technique (coordinate measuring machine Hexagon Global Performance 122210). The effectiveness of nondestructive testing in industrial conditions was assessed and the directions of further research in this area were indicated.
Ensuring the aerodynamic stability of the long-span bridges through studies in the wind tunnel
Authors: Khrapunov Evgenii , Solovev Sergei
Published: December 2018

The main ideas of the aerodynamic studies of large bridges are presented in present paper. Main types of aero-elastic instability for bridges with spans over 100 meters are considered. A two-step modeling approach is presented. At the first stage, the aerodynamic characteristics of the span fragment are considered, at the second.stage the characteristics of the whole bridge. Methods for investigation of bridge oscillations in a special-purpose experimental facility – the Landscape Wind Tunnel – are described. Examples of tests with elastic similar models of bridges are given, and measurements to mitigate dangerous oscillations early in the bridge design process are described.
The temperature - insulative material that can work as the insulation and siding and decorative material
Authors: Aksenov Boris , Stepanov Oleg , Stefurak ludmila
Published: December 2018

The article analyzes the new temperature - insulative materials. It is motivated that the temperature - insulative material capable to work in the panel as a temperature insulative and facing-decorative material can be only composite type. The composition of the new material, the technology of its production, as well as the mathematical model of the mechanism of formation of strong crusts at its surfaces. The material that is used for the manufacture of roofing panels, panels BKU with an internal non-metallic layer. These panels allow you to break the bridges of cold in butt joints, which improves thermal performance, reliability and durability of the building as a whole. Based on the developed mathematical model, you can predict the properties of foam plastic.
Amorphous fiber based on the Fe-B-C molten system for bulk reinforcement of concrete
Authors: Cherkashin Artemiy , Begich Yasmin , Sherstobitova Polina , Tolochko Oleg
Published: December 2018

The article deals with the use of amorphous fiber of the Fe-B-C system, which was obtained by spinning the melt. Comparative tests of the samples made on the basis of the test material on the compressive strength and tensile strength of the traditional destructive method were made. The conductivity of the samples was also tested. Physical and mechanical characteristics of the material are obtained.
The phenomenon for the wood creep in the reinforced glued wooden structures
Authors: Roshchina Svetlana , Lukin Mikhail , Lisyatnikov Mikhail , Koscheev Artem
Published: December 2018

For the composite structures based on wood, that include reinforced wooden structures, allowance for the influence of wood specific features as a building material allows us to evaluate its structural design as accurately as possible and ensure the required reliability and durability. Creep that causes wood deformations evolving in time can be referred to the specific properties of wood to a greater extent affecting the operation of the reinforced wooden structures. Taking into account the state of the issue to determine the effect of the long-acting loads on the stress-strain state of the reinforced glued wooden structures, the article considers the application of the theory of elastic heredity as the most applicable to assess the deformability of wooden structures in time. The conducted experimental and theoretical investigations and the reinforced glued wooden structures observations during the operational process have shown that their stress-strain state changes significantly under the load over time. Glue compositions used to connect reinforcement with wood ensure their reliable joint operation, however, as the result of the wood creep where wood is the basic material, the redistribution of forces between the reinforcement and wood occurs there on and off. At the same time normal stresses in the reinforcement and the glue joint “reinforcement - wood” increase in the calculated cross sections while they decrease in the wood, which is caused by a change (decrease) in the wood elastic modulus. Allowance for the wood creep in the design of the reinforced wooden structures will allow to determine the stress - strain state of the structure in the design more precisely. Therefore, when developing the reinforced wooden structures design standards, this factor must be taken into account.
Explanatory investigation of the device for regulating the vertical position of a building
Authors: Petrakov Aleksandr , Bryzhata Ekateryna , Maslo Nikolay
Published: December 2018

The article is devoted to the study of the strain-stress distribution of the frame elements of a multi-storey building with the correction of the tilt using a device for control the vertical position. The construction of the device for adjusting the geometric position of the building, which undergoes deformation of the ground base, is considered. Quoted results of experimental researches of the developed device for correction the tilt of a building. The influence of the loading level, sand moisture, the height of the intersection of the slots and the sand composition on the efficiency of the tilt correction device is analyzed.A finite-element model of a multi-storey building with constructive measures of protection against the influence of above permitted standard tilts, taking into account the interaction of the structure with the deformable ground base and the construction of foundations with variable dimensions are developed.The schemes for the multi - stage correction of the tilt of the finite - element model of the building are investigated.
Usability of gaming environments in cybersport
Authors: Sergeev Sergey , Kaklauskas Arturas
Published: December 2018

The article is devoted to the issues of engineering and psychological evaluation of gaming interfaces and environments for eSports. The typical program interface of group computer games is analyzed from the point of view of their user properties (usability). The functions and structure of the game interface are discussed. Definitions are given and the main usability functions are considered as an application to the gaming systems used in eSports. The basic requirements for user properties are formulated, and definitions of usability are given in accordance with the requirements of the International Organization for Standardization (ISO). The basic concepts of usability testing are given.
Investigation of flow and heat transfer at the circular fins
Authors: Mityakov Vladimir , Gusakov Andrey , Seroshtanov Vladimir , Grekov Michail
Published: December 2018

For simultaneous investigation of heat transfer and hydraulic parameters of finned circular tube is proposed to connect PIV (Particle Image Velocimetry) method and thermal imaging with gradient heat flux measurement. In the first series of experiments, the hollow fin was investigated. The hollow fin was heated with saturated water steam and its isothermal surface simulated the ideal (isothermal) fin. The solid fin made of titanium alloy was investigated in similar regimes for comparison. In the second series, the influence of distance between fins on the heat transfer coefficients (HTC) at the circular fin, mounted on a circular cylinder was studied. The unique Gradient Heat Flux Sensors (GHFSs) were installed at different places of the fin surface. Comprehensive method including heat flux measurement, PIV and thermal imaging allows to study flow and heat transfer at the surface of the fin in real time. Possibility of complex study of flow and heat transfer for non-isothermal fins is shown.
The implementation of energy-service contracts in the Republic of Sakha (Yakutia) as a tool to reduce government spending: experience and prospects
Authors: Slobodchikov Egor , Baisheva Lidiya , Syromyatnikov Vladimir
Published: December 2018

The article analyses the results of implementation of the energy-service contracts in the Republic of Sakha (Yakutia). A review of the Russian energy service market has been completed. Real savings of energy carriers according to metering devices in public enterprises, indicating the effectiveness of the technologies used, have been achieved. The used energy-saving technologies and solutions that allow one to achieve economic effect are considered. It is established that the existing mechanism of energy service allows the renovation of buildings with high-quality engineering support and high thermal protection of the shell.
Experimental investigation of the heat exchange intensity
Authors: Davletbaev Vladimir , Rydalina Natalia , Antonova Elena
Published: December 2018

We study heat exchangers at the experimental setup aiming at the energy-saving. The feature of this heat exchange process is of the fact that the working medium is a porous metal. The pores are filled with freon and operation of the refrigeration unit condenser is studied. The scheme of the experimental setup and experiment methodology are given. The results of the experiment and its processing are also presented.