bluuebunny/crossref_metadata_2025 huggingface dataset:
Rime ice growth characterized by surface acoustic wave
Authors: Yin Yining , Cheng Lina , Wang Wen , Zhang Yufeng , Liang Yong
Published: November 2021

We propose a new theoretical method and experimental investigation to characterize the growth process of rime ice through surface acoustic waves (SAWs). The Biot theory of dual-phase porous media was employed to construct a theoretical model to describe the acoustic wave propagation in porous rime ice; the transient changes in acoustic propagation attenuation and velocity were simulated; and the icing sensing mechanism of the acoustic wave propagation attenuation (∼18 dB) and the transient change in velocity (0.8 m/s) during the icing process was obtained. A 177.5 MHz waveguide type SAW micro–nano-device with an SU8/ST-90°X quartz multilayer composite film structure and a microfluidic cavity on the top of the acoustic device were designed and fabricated, and the transient attenuation in the growth of rime ice was evaluated experimentally. The experimental results indicated that the appearance of rime ice can be monitored accurately by utilizing the transient changes in acoustic wave velocity and attenuation. Therefore, the acoustic method can aid in the early warning of the development status of rime ice.
Near-field hyper-spectral imaging of resonant Mie modes in a dielectric island
Authors: Granchi Nicoletta , Montanari Michele , Ristori Andrea , Khoury Mario , Bouabdellaoui Mohammed , Barri Chiara , Fagiani Luca , Gurioli Massimo , Bollani Monica , Abbarchi Marco , Intonti Francesca
Published: November 2021

All-dielectric sub-micrometric particles have been successfully exploited for light management in a plethora of applications at visible and near-infrared frequencies. However, the investigation of the intricacies of the Mie resonances at the sub-wavelength scale has been hampered by the limitations of conventional near-field methods. In this paper, we address the spatial and spectral mapping of multipolar modes of a Si island by hyper-spectral imaging. The simultaneous detection of several resonant modes allows us to clarify the role of the substrate and the incidence angle of the impinging light, highlighting spectral splitting of the quadrupolar mode and resulting in different spatial features of the field intensity. We explore theoretically and experimentally such spatial features. Details as small as 200 nm can be detected and agree with simulations based on the finite difference time domain method. Our results are relevant to near-field imaging of dielectric structures, the comprehension of the resonant features of sub-micrometric Mie antennas, beam steering, and the resonant coupling with light emitters. Our analysis suggests a novel approach to control the absorption of a single emitter in the framework of surface enhanced absorption or stimulated emission applications.
Are we on the same page? Mental health literacy and access to care: a qualitative study in young Hazara refugees in Melbourne
Authors: Saberi Sahema , Wachtler Caroline , Lau Phyllis
Published: November 2021

Hazaras, mostly aged <30 years, constituted the greatest number of people resettled under Australia’s migration resettlement between 2009 and 2013. This group is at high risk of mental health issues due to pre- and post-forced migration experiences. This study explored the understanding of mental health and barriers to accessing primary mental health care in young Hazara refugees in Melbourne. Seventeen Hazaras aged 18–30 years were recruited for two sex-segregated focus groups; two individual semistructured interviews were also conducted (with one male and one female participant). Discussions were audiotaped, transcribed and analysed thematically. Participants had varied perspectives on mental health issues stemming from historical and current beliefs. Lack of knowledge and concerns over confidentiality within Hazaras were considered major barriers to seeking help. Community education through existing community groups and through the women could potentially help overcome barriers to mental health access by young Hazaras.
Synaptotagmin 1 oligomerization via the juxtamembrane linker regulates spontaneous and evoked neurotransmitter release
Authors: Courtney Kevin C. , Vevea Jason D. , Li Yueqi , Wu Zhenyong , Zhang Zhao , Chapman Edwin R.
Published: November 2021

Significance

Synaptotagmin 1 (syt1) is a synaptic vesicle (SV) protein that is rapidly activated by Ca
2+
influx into presynaptic nerve terminals, triggering SV exocytosis. Syt1 also inhibits exocytosis, prior to Ca
2+
influx, and thus helps synchronize evoked exocytosis upon Ca
2+
binding. Herein, we identified a cluster of lysine residues, in the oft-ignored juxtamembrane linker region of syt1, that governs homo-multimerization in an anionic lipid-dependent manner. Neutralization of this positively charged region abolished syt1 self-association on phospholipid bilayers in vitro. Subsequently, in neurons, we found mutations that disrupted syt1 self-association were correlated with defects in clamping spontaneous SV release and in triggering and synchronizing evoked exocytosis. Thus, syt1 regulates SV exocytosis as an oligomer via charged residues in the juxtamembrane linker.
Turn-taking in dialogue interpreting
Authors: Tiselius Elisabet , Dimitrova Birgitta Englund
Published: November 2021

This study addresses cognitive aspects of turn-taking and the role of experience in dialogue interpreting, by
investigating the temporal and textual properties of the coupled turn (i.e. the original utterance and its
interpretation). A comparison was made using a video-recorded scripted role-play between eight interpreters, with Swedish-French
or Swedish-Spanish as working languages and with different levels of experience. Cognitively challenging long stretches of talk
were introduced in both directions of the working languages and analyzed with a multi-modal approach. We identified a number of
quantitative measures, such as the number of coupled turns and the time used. Furthermore, we qualitatively analyzed the types of
renditions. The findings suggest that the mean length of time of the coupled turn, which we label processing
span, is a measure that is not primarily related to interpreting experience but rather reflects the constraints of the
interpreter’s working memory. A further finding is that the inexperienced interpreters have a higher percentage of reduced
renditions than the experienced interpreters, and this difference is statistically significant.
Investigating post-editing effort
Authors: Stasimioti Maria , Sosoni Vilelmini , Chatzitheodorou Konstantinos
Published: November 2021

The working environment of translators has changed significantly in recent decades, with post-editing (PE)
emerging as a new trend in the human translation workflow, particularly following the advent of neural machine translation (NMT)
and the improvement of the quality of the machine translation (MT) raw output especially at the level of fluency. In addition, the
directionality axiom is increasingly being questioned with translators working from and into their first language both in the
context of translation (Buchweitz and Alves 2006; Pavlović and Jensen 2009; Fonseca and Barbosa 2015; Hunziker Heeb 2015; Ferreira 2013, 2014; Ferreira et al. 2016; Feng 2017) and in the context of PE (Garcia 2011; Sánchez-Gijón and Torres-Hostench 2014; da Silva
et al. 2017; Toledo Báez 2018). In this study we employ product- and
process-oriented approaches to investigate directionality in PE in the English-Greek language pair. In particular, we compare the
cognitive, temporal, and technical effort expended by translators for the full PE of NMT output in L1 (Greek) with the effort
required for the full PE of NMT output in L2 (English), while we also analyze the quality of the final translation product. Our
findings reveal that PE in L2, i.e., inverse PE, is less demanding than PE in L1, i.e., direct PE, in terms of the time and
keystrokes required, and the cognitive load exerted on translators. Finally, our research shows that directionality does not imply
differences in quality.
Stress, cognitive, emotional and ergonomic demands in interpreting and translation
Authors: Gieshoff Anne Catherine , Lehr Caroline , Hunziker Heeb Andrea
Published: November 2021

The autonomic nervous system is responsible for modulating peripheral functions in the human body and consists of sympathetic and parasympathetic branches. Its activation affects, among other things, heart rate, respiratory rate, salivation, perspiration, pupillary dilation, and blink rate. For some years now, physiological measurements have found their way into interpreting and translation studies to investigate, in particular, cognitive, emotional and ergonomic demands and stress in translating, interpreting and post-editing. We conducted a meta-review of publications from 1990 until 2020 in order to investigate the relevance of (a) the four constructs of emotional, cognitive and ergonomic demands and physiological stress and of (b) physiological data for translation and interpreting research. With our selection of search terms, we identified 369 publications investigating one of the four constructs, of which 28 use physiological data. Analysis of the 28 studies shows a tendency towards triangulating physiological with other types of data, which reflects the complexity of the investigated tasks and constructs. Moreover, there seems to be an effort to increase sample size, which is an important step towards more robust results in quantitative research in the field.
Bridging the epistemological gap
Authors: García Álvaro Marín
Published: November 2021

Despite Cognitive Translation Studies’ (CTS) interest in didactic applications, the actual impact of research on training programs has been modest in comparison with the advances made in terms of methodology, theoretical sophistication and expansion of the object of study. It is argued that the modest impact of CTS on training originates, on the one hand, in an epistemological problem – one of mild incommensurability – and, on the other, on the difficulty of developing realistic cognitive task models. Adopting constructs and models in CTS and didactics that share an embodied, extended view on cognition may contribute to fitting empirical data and describing skill development. To that end, a sketch of a template to develop translation task models is presented for discussion.
Discourse markers in relation tonon-verbal behavior
Authors: Mlakar Izidor , Rojc Matej , Majhenič Simona , Verdonik Darinka
Published: November 2021

The research proposed in this paper focuses on pragmatic interlinks between discourse markers and non-verbal behavior. Although non-verbal behavior is recognized to add non-redundant information and social interaction is not merely recognized as the transmission of words and sentences, the evidence regarding grammatical/linguistic interlinks between verbal and non-verbal concepts are vague and limited to restricted domains. This is even more evident when non-verbal behavior acts in the foreground but contributes to the structure and organization of the discourse. This research focuses on investigating the multimodal nature of discourse markers by observing their linguistic and paralinguistic properties in informal discourse. We perform a quantitative analysis with case studies for representative cases. The results show that discourse markers and background non-verbal behavior tend to follow a similar functionality in interaction. Therefore, by examining them together, one gains more insight into their true intent despite the high multifunctionality of both non-verbal behavior and DMs.
Predatory Journals and Meetings in Forensic Sciences: What Every Expert Needs to Know about This “Parasitic” Publishing Model
Authors: Dinis-Oliveira Ricardo Jorge
Published: November 2021

The emergence of the Internet has transformed all areas of society. This includes the universe of scientific publications, with several publishers now exclusively focusing on the electronic format and open access model while expanding to a megajournal scope. In this context, the pandemic of predatory open access journals (POAJs) and meetings are of grave concern to the academic and research community. This new shift within academia produces a variety of new victims; namely, the authors themselves. In turn, scientific knowledge is often discredited, with the public placing less trust in science. Now more than ever, performing research with integrity and selecting a journal in which to publish requires close attention and expertise. The “predatory movement” has developed increasingly sophisticated techniques for misleading people into believing what seem to be credible professional layouts and legitimate invitations. Initiatives such as the Jeffrey Beall’s list, the Cabell’s Scholarly Analytics and Think.Check.Submit offer some guidance to uncover the “parasitic” intervention of predatory journals and meetings, but specific education in this field is sorely needed. This work aims to review the main characteristics of predatory journals and meetings and to analyze this topic in the context of forensic and legal medicine research.
Research on influence of mesh parameters modification on solution accuracy of finite element analysis
Authors: Handrik M , Majko J , Vaško M , Dorčiak F , Kopas P
Published: November 2021

The paper deals with the solution accuracy of the stress in the structure using the finite element analysis. In general, hexahedron elements are more accurate than tetrahedron elements and quadratic elements are more accurate than linear elements. The primary aim of the article is to perform comparison of the obtained results and calculation parameters (such as time and so on) for different types of elements and the elements size. Usage less accurate elements like linear tetrahedron under certain circumstances could lead to sufficiently accurate result of stress analysis.
Thermal specification of 3D printed injection moulds made from PA12GB
Authors: Raz K , Chval Z , Habrman M , Milsimerova A
Published: November 2021

This paper deals with the usage of the injection mould made from the plastic material. This technology is rapidly decreasing the time, necessary to the production of the prototype. This attribute takes nowadays a key role in the industry, especially in the automotive. Technology of using injection moulds from the plastic material (produced by additive technologies) has advantages in the decreasing of the time demands and cost reduction during the production of the prototype part. Unfortunately, plastic moulds have worse surface quality, lower lifetime of the mould (measured in number of produced parts) and more difficulties of moulding process regulation with respect to the metal moulds. This paper is focused on the injection process and it is describing the thermal distribution and specification of the comparable plastic specimen during injection into the metal and plastic mould. The results are the temperature and cycle-times comparisons. The effectivity of cooling is also compared in this work. It is obvious, that the plastic mould has worse results compared to the metal mould. However, this is clearly balanced by the speed of production and price of plastic mould. The prototype of the plastic mould was made from the material PA12GB with usage of 3D printer HP MJF4200
Design and FEM strength analysis of an innovative design of a front loader with an extension dedicated to the KUBOTA M5
Authors: Gierz Łukasz , Zwiachel Tomasz , Spadło Mikołaj , Olga Zharkevich , Kukesheva Aliya , Marx Ainash , Mataj Maciej
Published: November 2021

Most of the front loaders are compact structures that do not allow loading at greater heights. On the Polish and foreign market, there was a need to develop a front loader design that would allow to increase the loading height. As a result, the front loader was designed a front loader with the possibility of extending the arms for the Kubota M5 agricultural tractor. The system enables unloading and loading of cubes, straw and hay bales on higher piles. Before starting the design process, the available front loader solutions were analyzed and on this basis, three concepts of design solutions were proposed. These concepts were scored on the basis of the adopted criteria and the one with the highest number of points was selected. For the selected concept, strength analytical calculations and verification calculations using the FEM method were performed. The developed loader is innovative compared to other available designs and has a good chance of implementation.
Simulation model for evaluation of ergonomic load in the use of exoskeletons
Authors: Onofrejová D , Balážiková M
Published: November 2021

For the analysis of musculoskeletal workload and associated potential hazardous working conditions as well as musculoskeletal symptoms in worker populations among various occupations different approaches are taken, and extensive data collection studies are being accomplished. Questions are targeted on musculoskeletal workload and associated potentially hazardous working conditions can be categorized into seven indices (force, dynamic and static load, repetitive load, climatic factors, vibration and ergonomic environmental factors). Evaluation focus on standing, sitting, walking and uncomfortable postures, the indices constitute a brief overview of the main findings on musculoskeletal workload and associated potentially hazardous working conditions. The validity of the findings is fair when compared with an index of psychosocial working conditions and discomfort during exposure to physical loads. Worker groups with contrasting musculoskeletal loads can be differentiated on the basis of the indices and other factors. It appears that most indices and factors show significant associations with low back and/or neck-shoulder symptoms. This simulation model NIOSH analysis can be used as a simple and quick approach to identify worker groups in which a more thorough ergonomic analysis indicates possible improvements in load factor using particular exoskeletons at work.
Study vibration of worm gear boxes
Authors: Šmeringaiová A
Published: November 2021

The article describes the method of experimental analysis of transmission mechanisms. The test station enables to test different types of gears and to simulate their different operating conditions close to reality. The tests may be short-term and long-term. The course and results of the test operation of the screw reducer are described. Measured and evaluated were low-frequency and high-frequency vibration, temperature and wear functional parts of the teeth.
The use of digital filtration methods in AGV laser navigation systems
Authors: Dobrzanski P , Dobrzanska M
Published: November 2021

Recognition of the surroundings of automated guided vehicles (AGV) is one of the basic factors ensuring their proper movement in the field. The aim of the article is to present the use of a laser scanner to locate the position of objects in the vehicle's surroundings as well as to present the results of simulation of the analyzed methods of filtering the measurement results.
Modeling the damages of belt gears
Authors: Elżbieta Gawrońska , Grzegorz Domek , Piotr Krawiec , Andrzej Kołodziej
Published: November 2021

This paper looks into the problem of choosing a driving belt for a drive. The previously developed selection of algorithms was subjected to another evaluation that helped us recognize the need for changes indicated in developing new designs of drive belts. The new algorithm will be tested by simulating the operating conditions of the transmission, to which the right belt must be selected. Damage assessment after operation and belt selection allows for the identification of a new coupling model. By presenting the relationship between specific failure cases and the parameters of the coupling model, we can see the functionality of the selection algorithm. There may be multiple belt transmission damages. The feed may be broken; the surface may be damaged; the same applies to the edges. Furthermore, the wheels and bearings may be damaged too. The belt can have many additional functions that affect its operating parameters. Next to the drive function, the belt often performs conveyor and control functions. Thus, additional types of damage occur in belts with additional functions. The number of causes of their occurrence is also growing. For example, any damage to the sling in the passenger elevator can endanger the life of the passengers. Intensive research is being carried out on the real-mode damage monitoring systems. Specific failures are being monitored, and appropriate systems are being designed for them. Therefore, it is important to investigate the damages to belt transmissions, modeling their course of progression and causes.
Constructional design of the body shape of large gear wheels
Authors: Sivák S , Maláková S
Published: November 2021

The development of modern machines and means of production is characterized by ever-increasing performance parameters with decreasing equipment weight. When designing large gears, it is also necessary to consider the influence of the body shape of the gear wheel. The body shape of gear wheel must meet the basic requirements of stiffness and strength with the lightest possible construction of the gear wheel body. The work is focused on large gears, made with relief. Such gears can be forged, cast, or made by welding. The shape of the gear wheel body depends on several factors such as the size of the wheel, the material, the method of manufacture or use. The paper provides an overview of the body shapes used by large spur gears. These body shapes of spur gears will be the subject of further research, where suitability will be assessed based on stiffness of teeth and wheel weight.
Elastic modulus of defected graphene sheets
Authors: Bocko J , Lengvarský P
Published: November 2021

In this paper, the elastic modulus of single-layered graphene sheets (SLGSs) with and without defects is investigated using the finite element method. The SLGSs with two chiralities (armchair and zigzag) are modeled by beam elements. At first, the SLGSs without defects are investigated then the carbon atoms and corresponding beam elements are removed and the elastic modulus of SLGSs is determined. The increasing number of defects apparently decreased the elastic modulus of graphene sheets.
SMART Identification by Vision System
Authors: Demčák J , Husár J , Hladký V
Published: November 2021

The paper describes a machine vision system for SMART identification of objects. In the introduction, this system is analyzed from a theoretical point of view. Advantages and possibilities of its use are emphasized. The following section presents our research workplace, where the machine vision is located. It involves two identification stations, one of them with 3D measurement and the second is a 2D multi-spectrum with several types of lighting. One part of this section describes the workplace in 2D view and equipment of vision system situated in this laboratory. The third part examines the possibilities of character identification by this system. The novelty of the paper is presented experiment with different wavelengths of light (RGB, UV, AM, W, infrared, far-red). The result of experiment is the most suitable light for characters identification by vision system.
Multibody system simulation as a predictive tool for possible estimation of negative effects caused by vibrations of FDM device
Authors: Kaščak J , Kočiško M , Knapčíková L , Coranič T , Tôrôk J
Published: November 2021

The design of fused deposition modeling (FDM) devices in their current form is associated with many negative effects, which result mainly from their construction deficiency. Due to the constant effort to increase the accuracy and speed of these devices, we often encounter the emergence of various negative factors. One of the most significant factors is the presence of negative vibrations of the frame and individual components. These are directly linked to several shortcomings that FDM devices come with. Efforts to make the structures as simple as possible, their low weight or the use of filament extruders placed directly on the printheads and axis travels, are perceived as well-known shortcomings. These negative phenomena are subsequently manifested by the emergence of specific defects visible on the surface of the manufactured models. The article presents the possibility of predicting the occurrence of these negative phenomena, with the use of multibody simulation. This simulation analyzes the movements of a specific device at different print speeds. The article then presents the results of these simulations and analysis of the transmission of negative oscillations at specific critical points of the FDM device. Finally, the article examines the influence of possible regulation of devices acceleration rates caused by electrical motors in individual axes and their influence on the final surface quality of the manufactured model. The article points out the possibilities of using this type of simulation processes and analysis in the design process of new types of frames and translation mechanisms for FDM devices.
Virtual reality and its possible integration into the process of distance learning focused on technically oriented subjects
Authors: Franas E , Kočiško M , Kaščak J , Hlavatá S , Vodilka A
Published: November 2021

Individual digital technologies which are aimed at simulation of real world elements are currently one of the most promising areas of interest. The growing popularity of the augmented, virtual reality technologies, as well as the industries in which their application has an increasing impact, is causing a sharp growth in the number of specialized software. An increasingly popular sector in which virtual and augmented reality has promising prospects in the field of education. It was this area that created space for the application of various software solutions during a pandemic situation. The application focused on the distance form of educational process, training and mediation of interactive experiences, which subsequently mitigate the teaching process, has found application not only in technically oriented areas. This article presents the possibilities for usage of the virtual environment created in the Rinoceros software, which is used as a supporting tool for the teaching process of technically oriented subjects. The article describes how to apply and modify specialized software for a specific area of use. Particular type of VR/AR devices are used to mediate an interactive form of teaching, towards a specific group of students. Due to the intention of increased efficiency of this process, the article presents the possibilities of using the multiuser - host/guest functions, for full interactivity of more users. This solution allows the users to work with 2D, 3D models and CAD model assemblies in a virtual environment. It also presents the possibilities and promising areas of use which describe the other software features and their possible application in other areas, such as reverse engineering and intuitive modeling.
Influence of asymmetric airflow on the cooling performance of brake disc of railway vehicle
Authors: Pavelcik V , Fomina Y
Published: November 2021

The main objective of this article is to discuss the influence of asymmetric airflow on the cooling performance of the brake disc. This asymmetry might be caused by the air inlet pipe curvature of the UIC test bench for frictional components, whereas in reality this asymmetry might be caused by various factors. In the first part of the paper, a brief summary of effects of heat and temperature changes on the brake disc is presented. Additional information about UIC test bench is given with the focus on cooling effects of airflow on the disc. In the second part, a CFD simulation was made, and its settings and results are presented in detail. In the last part, temperature differences in various time points and positions on the brake disc are compared graphically in order to assess the influence of airflow from the inlet pipe and its curvature on the cooling performance of the brake disc.
The use of illite in function of filler applied in rubber blend
Authors: Pajtášová M , Pecušová B , Ďurišová S , Ondrušová D , Mičicová Z , Feriancová A , Brigantová S
Published: November 2021

The presented work was dealing with the study of the commercial filler influence change in rubber blend by an alternative filler based on the clay mineral - illite. The focus of the presented work was aimed at the study of selected curing characteristics of rubber blend with addition of clay mineral filler and physico-mechanical properties of prepared vulcanizates. Curing characteristics, the processing safety, minimum and maximum torque, optimal curing time and curing rate coefficient were determined during the curing experiment phase. Selected physico-mechanical properties were given by the determination of hardness, tensibility and tensile strength. The obtained results proved the possibility of partial commercial filler replacement by an alternative filler and the positive effect of clay mineral on resulting important properties in rubber industry.
Study of new elastomeric composite systems containing wood ash based alternative filler
Authors: Ondrušová D , Božeková S , Pajtášová M , Labaj I , Božek M , Vršková J , Skalková P
Published: November 2021

The presented paper deals with the preparation of the new types of elastomeric composite systems containing an alternative filler based on wood ash or fly ash. Wood ash (fly ash) is generated as the waste from the process of wood pellets burning in the pellet boilers. The results of the EDX analysis confirmed that CaO and SiO2 are the most represented components of wood ash, which contains commonly used white fillers, such as kaolin or silica. Therefore, wood ash was used as an alternative ecological filler in a function of a partial replacement for the commonly used carbon black filler in the elastomer systems. Rheological properties and cure characteristics of prepared elastomer composite systems and tensile properties of resulting vulcanizates have been studied. The prepared elastomeric systems were also subjected to a Payne effect study. The obtained results showed the degree of filler - filler interactions as well as the degree of mutual interactions between alternative filler particles and elastomeric matrix.
Curing characteristics and rheological properties of bentonite- filled rubber blends
Authors: Mičicová Z , Božeková S , Pajtášová M , Ondrušová D
Published: November 2021

The study deals with the examination of the rheological behaviour of rubber blends which were filled with bentonite. The filler - polymer as well as the filler - filler interactions were studied and determined from the frequency sweep and strain sweep rheological measurements. The used natural bentonite was extracted from the locality called Jelsovy Potok. The natural bentonite had a fine fraction with a particle size of 15μm a 45 μm and it was added into rubber blends as a partial replacement of commonly used filler. The rubber blends were characterised on the basis of curing characteristics (minimum torque ML, maximum torque MH, optimum time of cure t(c90), processing safety of blend ts,). Moreover, the complex viscosity and Payne effect were also specified. The required measurements were done by using PRPA 2000.
Component assembly for determination of elastomeric vulcanizate frictions
Authors: Labaj I. , Ondrušová D. , Vršková J. , Pajtášová M. , Feriancová A.
Published: November 2021

This article deals with the design and assembly of a component for determining the frictional properties of elastomeric vulcanizates. The component was design for a universal tensile machine, without needed of intervention to itself machine. The purpose of the work was designing a component in software SolidWorks and its subsequent assembly, as well as individual testing of frictional properties of selected specimens of elastomeric vulcanizates. Before of individual testing, the elastomer blends have to be vulcanised in the form of a block with a constant 16 mm height to ensure the same spring pressure on the specimens in the component. Then, by using rotary knife is from prepared vulcanizate cut a sample with 16 mm diameter. Result from friction properties measurement of samples is force needed to start of movement (shear) of sample over particular type of surface as well as graphical dependence of force (N) on movement of track (mm). From the graphical dependence, it is possible to determine the decrease or increase the force depending on the individual sections of the trajectory.
The influence of silane on the physico-mechanical properties of vulcanizates using bentonite fillers
Authors: Feriancová A , Dubec A , Pagáčová J , Labaj I , Pajtášová M
Published: November 2021

Layered phyllosilicate fillers have received attention in the polymer industry due to their unique nanoscale sheet-like structure. Adding a small amount of bentonite nanofiller gives rise to improved mechanical, thermal, and gas barrier properties of rubber mixtures. Depending on the application, natural bentonite is often modified by physical processes or by chemical processes (intercalation, cation exchange process, functionalization, pillaring, etc.). Chemical modification increases the size of the interlayer spaces and provides a hydrophobic environment. Functionalization (e.g., silanization), which encompasses the chemical grafting of thermally stable silane coupling agents onto the clay platelets, make inorganic bentonite and the organic polymer matrix compatible. In the introduced study, commercial bentonite P130 from Lieskovec deposit was modified by silane (3-aminopropyl trietoxysilane) treatment. Different techniques such as infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) were used to characterize modified and raw bentonite sample. Silanized P130s and raw product P130 were added to the natural rubber matrix to examine the influence of chemically functionalized bentonite on curing characteristic (M
H, M
L, t
s2, t
90, ΔM) and mechanical properties (TSb, Eb, hardness) of rubber vulcanizates. Organo-bentonite was mixed into a rubber blend in particular ratio of 5, 10, 15, 20 phr in various combination with silane (3-aminopropyl triethoxysilane), Perkasil and carbon black. The highest maximum torque values were obtained with the sample using 20 phr of silanized P130s. The tensile strength (TSb) values decreased with increasing P130 content, as well as non-silanized and silanized P130. However, when 20 phr P130s was used, value of TSb was higher. The most enhanced properties of rubber blends were found with the addition of 20 phr of silanized bentonite P130s.
Destructive and non-destructive testing of samples from PLA and PETG materials
Authors: Balint T , Živčák J , Hudák R , Tóth T , Kohan M , Lancoš S
Published: November 2021

This study deals with the properties of PLA and PETG materials, which are important for gaining knowledge in biomedical applications. The process of obtaining an ideal implant from a material with suitable mechanical and physical properties is a complex process considered to be one of the most difficult in tissue engineering. PLA and PETG material properties were determined based on performed non-destructive and destructive materials testing methods. Destructive testing was performed on Hegewald and Peschke equipment and non-destructive testing was performed on Carl Zeiss Metrotome 1500 (Germany). Commercial filaments from various companies were selected, from which type 5A dogbone samples were printed on a TRILAB printer. Subsequently, after carrying out the tests on dogbone samples, the results were evaluated and compared with the help of graphs and tables.
Modelling and optimization of energy intensity of an electrical discharge machine
Authors: Straka Ľ , Krenický T , Kuchta P
Published: November 2021

Nowadays, high fabrication productivity and high-quality products are a matter of course. However, it would not be possible without the use of highly sophisticated progressive technologies in the production process. But many of these modern production technologies are characterized by high consumption of energy. Given the current energy prices, this is not an insignificant amount of money. It is also necessary to point out, that in many cases the rule concerning the mutual interconnection of the energy intensity of production technologies with the resulting quality of the machined area applies. These reasons led us to the optimization of energy consumption in the context of the required quality of the machined surface in terms of selected indicators. The paper aims to describe the results of the performed experimental measurements in order to create mathematical models with subsequent optimization of electricity consumption of an electrical discharge machine. Unlike many types of research conducted in the field so far, the results of the solution were based on determining the relationships between the energy intensity of the electrical discharge machine and its controllable outputs in terms of the final roughness of the eroded surface. The performed optimization based on experimentally obtained results was directed so that its results could be applied in real conditions of technical practice.
System of Water Vehicle Power Plant Remote Condition Monitoring
Authors: Golovan A , Honcharuk I , Deli O , Kostenko O , Nykyforov Y
Published: November 2021

Remote condition monitoring of water vehicles plays an important role in preventing potentially very expensive marine incidents and ensuring maximum efficiency of a ship's operation and reliability with minimum maintenance downtime and repair costs. Concept of the condition-based approach to maintenance is today's best practise, and it is becoming increasingly important to move from planned maintenance to condition-based maintenance, to reduce the increasingly high cost of maintaining a modern fleet. Onboard and remote monitoring is now an essential part of condition-based maintenance process to obtain the good quality data, correct analysis, and effective counteractive actions necessary for such an approach, and article presents the water vehicle power plant monitoring model developed by authors. Considered approach, coupled with preventive maintenance, saves shipowners time and money through early diagnosis of component failure or excess wear. Power plant of water vehicle comprises far more than just an engine with its auxiliary equipment but also other main propulsion blocks – in particular, thrusters. The result was the development of the Water Vehicle Condition Monitoring (WVCM) system, which enables to closely examine water vehicle equipment performance. A WVCM system comprises the following installed onboard: accelerometers, pressure and temperature transmitters, oil, fuel and exhaust monitoring units and a torque measurement system.
Experimental verification tests of isokinetic equipment used in sport and rehabilitation
Authors: Harčarik G
Published: November 2021

Abstrakt

The paper deals with experimental verification of selected types of tests on isokinetic, diagnostic IsoForce2 training equipment. The isokinetic device provides accurate and immediate information about the developed strength in the exerciser's movement. The main criterion is its versatility when used in sport or rehabilitation. Therefore, it was necessary to create a portable adjustable structure that allows all the movements to be carried out and must meet other specific requirements. An important information is the amount of data collected, which is collected through the measurement system and then analyzed. The first test was elbow flexion, which was verified in arm-wrestling. The second test was knee flexion, which tested patients in rehabilitation after knee surgery to determine the difference in maximum strength between the lower limbs. The results of measurements are accurate, repeatable and provide athletes, patients, coaches and physiotherapists with immediate information about the level of strength abilities in a given type of test or movement.
Increase of Technical Condition Control Efficiency of Marine Railways
Authors: Honcharuk I , Golovan A , Voloshyn A , Kostenko O , Deli O
Published: November 2021

The paper presents the result of solving a relevant scientific and practical problem, which consists in the development of methods and diagnostic tools and improving the efficiency of monitoring the technical condition of transport equipment, in particular elements and units of marine railways, through the introduction of an automated system for diagnostics and monitoring of technical condition, which provides an increase in the reliability of diagnosis, reducing the time and cost of diagnostics. The analysis showed that the existing methods for determining the main parameters of the technical condition of elements and units of slips, which are the basis for reliable diagnostics of the technical condition, need to be improved. A method has been developed for monitoring the integrity of the main elements of marine railways based on the analysis of the temperature and natural vibration frequency of the main elements, which, in contrast to the existing methods, gives an error in measuring the signal frequency of less than 0.05%, which makes it possible to determine defects at early stages of their development.
The Concept of Implementation of Multifrequency RFID System Industrial Involvement in Laboratory Conditions
Authors: Husár J , Knapčíková L , Hrehová S
Published: November 2021

People have been dealing with the correct identification of objects for a long time. In industry, we cannot avoid this area, whether it is to identify people, semi-finished products or final products. Therefore, this article deals with the design of a multifrequency RFID system for industry 4.0. The idea of the article is to implement one type of identification technology for tracking objects using the radio frequency spectrum at different wavelengths. We have based our design on the built industrial-assembly line in the SmartTechLab laboratory, where we have implemented LF, HF and UHF systems connected by an industrial PLC into a complex system. In this article, we gradually focus on the selection of RFID systems, their cooperation and the design of connection to one portable box. Using an RFID box, we can monitor different types of objects and verify RFID reading using a single reading device or by creating portal RFID gateways. The implemented system consists of four middleware and four independent antennas that can cooperate. For proper operation, there is necessary implement not only hardware but also necessary software. The system can identify RFID tags in the range of 1 cm to several meters. Also, the advantage of the design is that it identifies all types of tags (industry, label, ceramic, laundry, paper). One of the main benefits of the design is modularity, mobility and the creation of a robust design that can be used for measurements in companies and also for educating students in laboratory conditions. The whole system is designed to meet the requirements of Industry 4.0 and improve the competitiveness of businesses.
Thermo-elastostatic analyzes of new dampers made of polymer springs with negative thermal expansion
Authors: Murín J , Goga V , Paulech J , Hrabovský J , Sedlár T , Kutiš V , Aminbaghai M
Published: November 2021

The article presents original results of research of the dampers with passive and semi-active damping using polymer springs (also artificial muscles or nylon springs) with negative thermal expansion. Passive damping can be ensured by the strong damping effects of polymer springs. Semi-active damping can be provided by heating the springs from an additional heat source. According to design such dampers, mathematical models for analytical elastostatic and thermoelastostatic analyzes of dampers for selected load cases are processed in the paper. The permissible values of mechanical and thermal load of the dampers are determined. The obtained results are verified by numerical analysis using the finite element method. The elastostatics of the passive damper and its damping functionality have been verified on a real model of the damper. The compiled mathematical models can be used in the design of polymer dampers as well as in their automatic control. Designed and analysed dampers can be used in smaller mobile or stationary systems such as scooters, small car kits and the like. The elastodynamic functionality of the dampers with passive and semiactive damping will be presented and discussed in our further paper.
Influence of the parameters of the extrusion process on the properties of PLA composites with the addition of graphite
Authors: Fiedurek K , Szroeder P , Macko M , Raszkowska-Kaczor A , Puszczykowska N
Published: November 2021

The main purpose of the work is to determine the influence of the screw diameter on the parameters of the single screw extrusion process, such as power consumption, torque, throughput, the actual temperature of the melt on the extruder die, as well as phase s with the use of a laboratory single-screw extruder.. The research was carried out with the use of various plasticizing systems. Two types of graphite: pre-expanded and normal grade with different grain sizes were used in the research. Flammability tests of the obtained composites were carried out using cone calorimeter.
The method of obtaining polymer masterbatches based on polylactide with carbon filler
Authors: Kaczor D , Bajer K , Domek G , Raszkowska-Kaczor A , Szroeder P
Published: November 2021

The method of obtaining polymer composites with a graphite filler using a kneading mixer was presented. The best mixing parameters (rotational speed and temperature) were determined, allowing to obtain composites with the best filler dispersion in the polymer matrix. A series of graphite/polylactide (PLA) masterbatches were made. The following composites tests were performed: scanning electron microscopy (SEM), infrared spectroscopy (FTIR-ATR), and differential scanning calorimetry (DSC). The value of the mass melt flow rate (MFR) was also determined. It was observed that the best homogenization were obtained for samples mixed at a speed of 40-50 rpm and at a temperature of 180-190°C.
Effective shaping of a bisymmetrical cross section of beams under shear stresses constraints
Authors: Magnucki K , Witkowski D
Published: November 2021

The subject of the studies is effective shaping of an analytically defined, bisymmetrical cross section of beams. The objective function concerns the maximum of the inertia moment and minimum of the area of the cross section. The constraint condition takes into account the maximum shear stresses. The effective shapes of the exemplary beams are derived. Results of the analytical study are presented in Tables and Figures.
Analysis of the usability of rolling resistance measurement methods to study the mechanisms of some wheelchairs
Authors: Warguła Ł , Kukla M , Yurchenko V , Kukesheva A
Published: November 2021

Reducing the driving force when propelling a wheelchair, e.g. through mechanical gears, is beneficial for people using wheelchairs. This makes it possible to overcome terrain obstacles that would be otherwise impassable with a classic drive system. However, the disadvantage of additional mechanisms supporting the propulsion of the wheelchair is usually the additional mass, ultimately increasing the rolling resistance. The article presents methods of measuring the rolling resistance – widely developed in the automotive industry – in terms of measuring the rolling resistance of wheelchairs. Innovative methods have been demonstrated to measure the rolling resistance on various surfaces and with the use of various drive mechanisms. The developed methods also enable the determination of the rolling resistance coefficient. The methods used are innovative and are subject to patent protection prepared by the authors in recent years. The results of the respondents allow to compare the measurement accuracy of the developed methods and show that the second method (being a simplification of the first method) is characterized by better accuracy.