bluuebunny/crossref_metadata_2025 huggingface dataset:
Biogenic Factor and Phosphogenesis: Legends and Realities
Authors: Georgievskiy A F , Bugina V M
Published: May 2021

The article discusses the role of organisms in industrial phosphorite formation. This question is not an idle one, because theoretical solutions and mineral research recommendations so important for the development of agriculture depend on its solution. Scientists have been dealing with this problem for more than a century, but they have not come to a common conclusion. No one doubts that biota, one way or another, takes part in phosphogenesis. Its role is interpreted in different ways: from indirect, to the main ores-forming. Now, after well-known experiments with the precipitation of phosphate by cyano-bacteria, the biogenic factor is again at its height. The material presented in this article shows that such a point of view is more based on emotions than on an impassive analysis of geological facts, such as the structure of stromatolite and oncolite Ediacaran phosphorites, as well as the results of geological exploration Russian and Mongolia deposits of the Okino-Khubsugul basin. These facts indicate a highly exaggerated role of cyano-bacteria in the formation of industrial phosphorites accumulations. So, the article concludes that the biogenic factor is an important, but not the main part of phosphogenesis. Most often, industrial phosphorite accumulations due to a combination of diagenesis processes with sediment rewashing, and early diagenetic phosphatization of precipitation becomes the ore-forming factor during the formation of structureless phosphorites. Finally, it is important to note that phosphogenesis is an extremely multifaceted natural phenomenon and it is counterproductive to put biogenic factor at the head.
Acoustic emission monitoring of composite specimens with impact damage during static compression test
Authors: Urbaha Margarita , Agafonovs Ivans , Turko Vladislav , Feščuks Jurijs , Korhs Juris
Published: May 2021

The standard specimens have been made by anisotropic carbon fiber plastic with an epoxy matrix. The specimens were subject to static load after its shock impact. During static compression loading, the parameters of acoustic emission (AE) signals were synchronously recorded: AE impulse amplitudes, its energy and the number of oscillations. According to the analysis of the acoustic emission signals the following events were observed: matrix cracking, fiber delamination and fiber destruction. The character of the AE signals change made it possible to determine the energy of the acoustic emission signals as a diagnostic witness of the onset of two moments of the specimen destruction. The first = near 70% of ultimate load’s (the destruction of matrix) and total destruction under ultimate static load.
Functionally Gradient Ti6Al4V-TiB Composite Produced by Spark Plasma Sintering
Authors: Liu Le , Ivanov Roman , Kumar Rahul , Minasyan Tatevik , Antonov Maksim , Hussainova Irina
Published: May 2021

Functionally gradient materials (FGM) are progressive materials, where the final characteristics are sequentially changing with dimensions. Direct fabrication of functionally gradient Ti6Al4V-TiB composite was performed by spark plasma sintering (SPS) technique. Powder mixtures of six different ratios of Ti-alloy and TiB2 were subjected to sintering at a temperature of 1350 °C and a pressure of 50 MPa with a dwelling time of 15 min to obtain a six-layer specimen. Scanning electron microscope images demonstrate smooth transition between layers. Vikers hardness (HV5) is 350 on the top side and 1038 on the bottom side, and a corresponding coefficient of friction (CoF) is 0.99 and 0.76, respectively, which demonstrates their different performance under sliding wear.
Towards Individualized Production with Flexible Shopfloor IT based on Distributed OPC UA Services
Authors: Wolff Tobias , Vick Axel
Published: May 2021

Nowadays, manufacturers face the problems to adjust their production according to the fast-changing global competition. Car manufacturers, for example, are in front of a new era of individual mobility. They need to switch from combustion engines to electric drives. In general, manufacturers have to develop production strategies to lower set up time and meet requirements faster. The classical production line is most effective if the product variety is low and the lot size is high but facing the rapid growing demand for individualized products and fast-changing requirements, manufacturers must discover new ways of manufacturing. One possibility is the flexible shopfloor. In this work, we will present our concept of a flexible shopfloor IT for controlling a robotic demonstrator. We use OPC UA over TSN as a platform for communication and CODESYS as Soft SPS for the control of sensors and actuators. In order to create valid data for ongoing discussions we use function point analysis and counting lines of sourcecode to measure software size. Our expectation is that the initial effort for implementing a flexible shopfloor IT is higher compared to the classic approach, but for all the following implementation it will take less time, because of the possibility of reuse already developed systems.
ROS middle-layer integration to Unity 3D as an interface option for propulsion drive simulations of autonomous vehicles
Authors: Kuts Vladimir , Rassõlkin Anton , Partyshev Andriy , Jegorov Sergei , Rjabtšikov Viktor
Published: May 2021

As autonomous vehicle development continues at growing speeds, so does the need for optimization, diagnosis, and testing of various autonomous systems elements, under different conditions. However, since such processes should be carried out in parallel, it may result in bottlenecks in development and increased complexity. The trend for Digital Twins brings a promising option for the diagnosis and testing to be carried out separately from the physical devices, incl. Autonomous vehicles, in the virtual world. The idea of intercommunication between virtual and physical twins provides possibilities to estimate risks, drawbacks, physical damages to the vehicle’s drive systems, and the physical one’s critical conditions. Although the problem of providing communications between these systems arises, at the speed that will be adequate to represent the physical vehicle in the virtual world correctly, it is still a trending topic. The paper aims to demonstrate a way to solve this problem-by using ROS as a middleware interface between two twining systems on the autonomous vehicle propulsion drive example. Data gathered from the physical and virtual world can be exchanged in the middle to allow continuous training and optimization of the propulsion drive model, leading to more efficient path planning and energy-efficient drive of the autonomous vehicle itself.
Adhesion of AlCrN coating deposited on TiB2/Ti composites sintered by SPS dedicated for high temperature tribological applications
Authors: Michalczewski R , Kalbarczyk M , Slomka Z , Hussainova I , Liu L , Antonov M.
Published: May 2021

The aim of the work was to investigate the adhesion of AlCrN coating deposited by PVD method on TiB2/Ti composites manufactured by Spark Plasma Sintering (SPS). The composites were produced from three kinds of mixtures of powders: (1) Ti and TiB2, (2) Ti6Al4V and TiB2 and (3) Ti and B. Each of the mixtures was prepared at 50/50 wt. % ratio of components. Before the coating deposition the specimens were polished to obtain the surface roughness typically required for machine parts. For each set of specimens an individual surface preparation procedure was developed. The coating adhesion was measured using a scratch tester. The process of scratching was carried out to observe the characteristic moments of adhesive and cohesive failures. The highest critical loads were obtained for the coating deposited on composites produced from the mixture of two powders containing pure Ti and TiB2.
User-centered design for Human-Robot Collaboration systems
Authors: Pizzagalli S L , Kuts V , Otto T
Published: May 2021

Autonomous robotic systems are one of the pillars of Industry 4.0, together with Digital Twin (DT) simulations and advanced Human Machine Interfaces (HMI). Customization requirements in modern manufacturing demand a closer collaboration between operators and automated technologies, leading to a novel Human-Robot Collaboration (HRC) and interaction paradigm aimed at the augmentation of human capabilities in the workplace. This scenario calls for a new definition of HRC standards and design for safety, programming, and an overall assessment of modern cyber-physical systems. A comprehensive design process aiming to formulate a common framework of requirements based on human, organizational and production needs is missing. A user-centered design approach described may be a solution to address the open challenges of future HRC. DT and Augmented and Virtual reality technologies (AR/VR) are implemented in elaborated model as the necessary tools to assign the operator a central position in the design, control, and assessment of modern industrial collaborative scenarios.
Modelling FGM materials. An accurate function approximation algorithms
Authors: Majak J , Mikola M , Pohlak M , Eerme M , Karunanidhi R
Published: May 2021

The study is focused on development of an accurate and cost effective function approximation techniques for modelling functionally graded materials. Different grading functions (exponential, power law) are expanded into Haar wavelet series based on higher order Haar wavelet approach. The proposed techniques can be utilized also for modelling load cases, complex boundary conditions, grading functions etc.
Benchmark Concept for Industrial Pick&Place Applications
Authors: Vick Axel , Rudorfer Martin , Vonasek Vojtech
Published: May 2021

Robotic grasping and manipulation is a highly active research field. Typical solutions are usually composed of several modules, e.g. object detection, grasp selection and motion planning. However, from an industrial point of view, it is not clear which solutions can be readily used and how individual components affect each other. Benchmarks used in research are often designed with simplified settings in a very specific scenario, disregarding the peculiarities of the industrial environment. Performance in real-world applications is therefore likely to differ from benchmark results. In this paper, we present a concept for the design of general Pick&Place benchmarks, which help practitioners to evaluate the system and its components for an industrial scenario. The user specifies the workspace (obstacles, movable objects), the robot (kinematics, etc.) and chooses from a set of methods to realize a desired task. Our proposed framework executes the workflow in a physics simulation to determine a range of system-level performance measures. Furthermore, it provides introspective insights for the performance of individual components.
The optimized electrochemical deposition of bismuth-bismuth telluride layered crystal structures
Authors: Bakavets Aliaksei , Aniskevich Yauhen , Ragoisha Genady , Tsyntsaru Natalia , Cesiulis Henrikas , Streltsov Eugene
Published: May 2021

Underpotential deposition, i.e. the cathodic deposition above reversible potential E(Men+/Me), produces an atomic layer of a metal on a semiconductor electrode, such as e.g. bismuth telluride. This phenomenon allows electrodeposition of superlattices formed of building blocks of a layered semiconductor structure joined by biatomic metal interlayer. This work outlines the optimized pulse potential controlled electrodeposition of (Bi2)m(Bi2Te3)n films produced under mentioned above technique. The influence on the morphology of the electrodeposited films of key-parameters as applied pulse frequency, duty cycle, a routine of sodium dodecyl sulfate introduction in the electrolyte is discussed. The optimized procedure comprises a short (about 10 s) cathodic pre-treatment at high overpotential of the cathodic reaction, the subsequent periodic switching for 120 min between potentials of electrodeposition and refinement at 0.1 Hz and 5% duty cycle with addition of surfactant 60 min after the start of the electrodeposition.
Assistance Method for the Application-Driven Design of Machine Learning Algorithms
Authors: Fono Adalbert , Thiele Gregor , Klein Max , Krüger Jörg
Published: May 2021

Machine learning (ML) offers a lot of potential for applications in Industry 4.0. By applying ML many processes can be improved. Possible benefits in production are a higher accuracy, an early detection of failures, a better resource efficiency or improvements in quantity control. The use of ML in industrial production systems is currently not widespread. There are several reasons for this, among others the different expertise of data scientists and automation engineers. There are no specific tools to apply ML to industrial facilities neither guidelines for setting up, tuning and validating ML implementations. In this paper we present a taxonomy structure and according method which assist the design of ML architectures and the tuning of involved parameters. As this is a very huge and complex field, we concentrate on a ML algorithm for time series forecast, as this can be used in many industrial applications. There are multiple possibilities to approach this problem ranging from basic feed-forward neural networks to recurrent networks and (temporal) convolutional networks. These different approaches will be discussed and basic guidelines regarding the model selection will be presented. The introduced assistance method will be validated on a industrial dataset.
Industry 4.0 readiness of manufacturing sector in the Baltic Region
Authors: Bazaz SM , Penttilä S , Ollikainen M , Ratava J , Varis J
Published: May 2021

The aim of the research is to provide a sample data and analysis to present the state of digitalization in the Baltic sea region. A matrix contains seven operation fields and ten services and technologies mapped available digital services in six countries like Denmark, Estonia, Finland, Latvia, Lithuania, and Poland. A comparison analysis describes the level of digitalization strength and weakness areas by country in Baltic sea region. Support structure analysis is a reference to select the suitable partner to enhance the level of digitalization in countries. The results show that there are differences in the strength and weakness areas in Baltic sea region. Further the strength areas of each country are compared to weakness areas of digitalization to develop a roadmap to improve the readiness to implement and use Industry 4.0 functionality and tools.
The method of tribotesting of PVD coated elements in oscillation motion at high temperature
Authors: Michalczewski R , Kalbarczyk M , Maldonado-Cortés D
Published: May 2021

The development of new types of coatings is realised by many scientific and technological centres in numerous countries. To evaluate new material solutions, researchers use various methods with wide range of tribotesters. Consequently, the obtained results are incomparable. The barrier of new technologies development, especially surface modifications dedicated to work at high temperatures, is a lack of worldwide recognised tribological test methods. This paper presents the method for tribological evaluation of tribosystems with PVD/CVD coated elements, in oscillatory motion and at high temperature (up to 900 °C). The method is realised by using SRV Optimol Instruments Prüftechnik GmbH (Germany) device. The realised verification tests proved the correctness of the elaborated methodology.
High-temperature abrasion resistance and wear mechanisms of chilled high-chromium cast irons
Authors: Widder Lukas , Rojacz Harald , Buscher Markus , Varga Markus
Published: May 2021

Hard and highly wear resistant chilled cast irons are of high interest in heavy industries like mining and steel production to achieve durable and sustainable wear protection. In this work a comprehensive view on abrasion mechanisms and the change in microstructure of these materials at elevated temperatures is targeted. Therefore, two different types of commercially available chilled high-chromium white cast irons were chosen. Detailed material characterization and hot hardness tests up to 1000°C were performed to get a first indication of temperature stability. For analysis of abrasive behaviour dry sand/steel wheel testing up to 700°C was conducted. A major part of the work was a thorough examination of the wear tracks and the influence on the microstructure. In the investigated materials chromium carbides Cr(Fe)7C3 and Mo-rich precipitations are present; the size and stoichiometry depend on the chemical composition. According to the differences in carbide size and type and the respective matrix composition, the hardness and abrasive behaviour changes, especially at higher temperatures. Incorporation of SiC abrasive in the wear zone leads to an in-situ wear protection, which was especially effective at 300°C increasing material’s wear resistance compared to room temperature (RT). At higher temperatures up to 700°C it was possible to compensate the hardness loss of the cast iron materials.
Thermal properties of calcium-aluminate based materials
Authors: Kulu P , Goljandin D , Traksmaa R , Kaljuvee T , Gregor A
Published: May 2021

Good cementing properties, fast setting and strong thermal performance make calcium-aluminate a valuable raw material for use in the production of different types of new refractory materials, e.g., heat conductive/storage materials. The main aim of the study was to determine thermal properties of novel Nb-slag based materials with different fillers, and to clarify optimal composition and technology. Process of preparation of studied materials was following: mixing of components, casting to moulds and hardening of materials. To estimate potential application areas, we studied the following thermal properties of CA-based materials: thermal behaviour, coefficient of thermal expansion (CTE) and conductivity. For this small cylindrical specimens were cut out from produced materials, and plates sized 300 × 300 mm were used for conductivity studies. Different compositions of CA-based materials, the hardening process, and the influence of mechanical activation on the strength were analyzed. Best thermal properties similar to the analogous reference material were obtained by quartz sand and granite sand as filler materials. The thermal conductivity of the novel CA-based material is 1.5 times higher and the bending strength is about 3 times higher compared to commercial thermoplates.
Nature inspired optimization of jerk limited feedrate profile for NURBS toolpaths in CNC machines
Authors: Erwinski Krystian , Szczepanski Rafal , Tarczewski Tomasz
Published: May 2021

In this paper a novel approach to solving the feedrate optimization problem in Computerized Numerically Controlled (CNC) machines for Non-Uniform Rational B-Spline (NURBS) toolpaths is presented. Particle Swarm Optimization (PSO) gradient-free algorithm is used to determine the optimal shape of the feedrate profile. The shape of the profile is optimized to achieve shortest travel time within the constraints imposed by the machine’s axes. Compared to more common approaches the profile is initialized with a quasi-optimal shape determined by a feedrate limit curve and then optimized to the final shape. Simulation results are presented that show the performance and computational effectiveness of the proposed method.
Safety Assessment and Simulation of Autonomous Vehicle in Urban Environments
Authors: Malayjerdi Mohsen , Baykara Bariş Cem , Sell Raivo , Malayjerdi Ehsan
Published: May 2021

The Autonomous Vehicle (AV) industry aims to design strategic plans to ensure the safety of the developed systems before their mass deployment. Real-road testing is shown to be impractical for validating these systems as it requires many years if not decades of testing in different environmental conditions. Therefore, this method must be complemented with simulation for a feasible solution. The primary goal of this research is to develop advanced techniques in the safety validation area by using immersive simulation technologies. This study led to a simulation approach for safety evaluation of an AV shuttle, ise Auto, currently operating at the TalTech campus. First, we create a virtual environment based on the specified path on the university campus including all relevant features. The environment is created by using geospatial data which is collected by a drone, then they are converted to a 3D map applicable for the LGSVL simulator. Next, the developed shuttle 3D model is imported to the simulation environment and with the aim of the LGSVL, sensor data are provided for the Autoware perception algorithms, which is the control software of the shuttle. This system enables us to evaluate AV’s decision-making performance and safety in different situations.
Variations of ice friction regimes in relation to surface topography and applied operating parameters
Authors: Velkavrh Igor , Voyer Joëel , Wright Thomas , Lungevičs Jänis , Jansons Ernests , Boiko Irina
Published: May 2021

To evaluate the effects of surface topography, ice and ambient conditions on the sliding behaviour of steel samples on ice, in the present study friction and velocity measurements were performed with steel samples having different surface roughness values and distinct surface structures. It was shown that the influence of surface roughness on friction and sliding velocity is strongly dependant on ice conditions and the applied experimental parameters due to the formation of different friction regimes.
Modern Robot Integrated Manufacturing Cell According to the Needs of Industry 4.0
Authors: Moor Madis , Vaher Kristo , Riives Jüri , Kangru Tavo , Otto Tauno
Published: May 2021

The continuous need to develop Industry 4.0 branches has led to a position, where highly sophisticated and multi-layer smart robotic systems are conducting the way in future manufacturing. This study aims to build a connectivity and system intelligent layer on top of a Co-bot integrated CNC-based Manufacturing cell. The connectivity layer is used to bypass all the data from machines to the upper intelligent layer vice versa. When raw data is arriving in the intelligent layer it is converted to information and again to knowledge for reflection back to the cell. Machine to Machine Communication and Digital Twin process for optimization is used for data conversions. This study is a down-scale example of the CPS for further development of existing robot cells.
Supply Chain Digitalization Framework for Service/Product Satisfaction
Authors: Murumaa Lea , Shevtshenko Eduard , Karaulova Tatjana , Mahmood Kashif , Popell Janek
Published: May 2021

It is essential for every enterprise existence to satisfy customer and consumer. The main idea of the current research is to apply customer satisfaction level Key Performance Indicators (KPIs) for supply chain reliability improvement. The Supply Chain Operations Reference (SCOR) model based KPI metrics enables to increase the quality of product/service by monitoring, visualization and further digitalization of directly involved processes. In the long run, the solution will ultimately help to reduce/eliminate the number of customer reclamations in the supply chain.

The paper includes a customer satisfaction improvement feasibility case study for the approval of findings, where the garment field business processes are connected to KPI-s of product and service models. In addition, this work suggests modelling tools for faster product/service and business process modelling and evaluation (assessment) based on the selected strategic goal for each management level. The authors defend that the current research helps to create new digital solutions to increase reliability by moving toward the customer satisfaction.

Nevertheless, the proposed approach is adaptable to other fields also, whereas the small and medium enterprise (SMEs) focal player or project owner defines the processes that have the biggest impact on the product/service reliability.
Quality of Photovoltaic Modules, Experimental Evaluation and Mathematical Modelling
Authors: Tšukrejev P , Karjust K , Majak J
Published: May 2021

Over the world rapid growth of demand for photovoltaic systems installations brings forward magnificent increase in production numbers in manufacturing facilities of PV systems. Production companies are facing challenges in providing the best quality simultaneously with rising manufacturing quantities. Due to technology behind not all the quality decisions can be done in real time. This study is focused on the development of experimental study and mathematical modelling of the PV modules quality control parameters, which could only be tested during chemical processes and could not be monitored constantly by operators at the production line.
Detection of cracks in green products of powder metallurgy by means of laser vibrometry
Authors: Tatarinov A , Kurtenoks V , Mironovs V
Published: May 2021

Cracking of green parts in powder metallurgy (PM) is a big concern in PM industry. Detection of cracks in green parts before sintering can prevent recycling of already sintered parts or production of defective ones. As opposed to sintered parts, where the presence of cracks is well revealed by impact spectroscopy, it is challenging for green parts. The reason is an extremely low mechanical quality factor of these parts composed of compacted but non-sintered metal powder particles. Low mechanical integrity of particles causes the absence of pronounced resonances of the parts. The aim of the study was to test a possibility to discerning healthy and cracked green parts using spectral characteristics of signals obtained by laser vibromery. Four similar green PM gear wheels made of steel powder were obtained from a PM manufacturing company, two of them were healthy and two with simulated cracks that appeared in the area of stress concentration between the hub and the disc. The experimental setup included a Polytec PSV-500 scanning laser vibrometer and a Bruel&Kjer vibration stand type 4824. Integrated spectrograms in the frequency range 50 – 3500 Hz were recorded upon a 95-point network on the gear surface at different vibration intensities proportionally graded in the range from 1 to 5. Comparison of the 3D (frequency-intensity-amplitude) vibration spectrograms showed that the defected specimens with cracks differed from the healthy ones in the following features: resonance frequency shift and/or splitting of resonances when the load changes. The study confirmed the principal possibility of cracks detection in green PM parts using laser vibrometry regardless the crack location in the part. The aim of further studies is to determine the sensitivity limit in terms of crack size.
The effect of UV-C radiation on the durability of 3D printed plastic parts in disinfectant devices
Authors: Tähemaa T , Sarkans M , Sarand I , Pohlak M , Niidas A , Saarna M
Published: May 2021

The usage of far or hard ultraviolet radiation in wavelength 200 – 280 nm or shortly UV-C disinfectors are becoming more and more popular due to their universal ability to fight against bacteria and viruses. It is well known that according to DIN 5031-7, both UV-A and UV-B radiation from sunlight have clear influence on the mechanical and visual properties of plastic parts, but the influence of intensive artificial UV-C is not so widely investigated. As the UV-C is in the shorter end of the UV radiation wavelength spectrum and is completely absorbed by the ozone layer and atmosphere, it is not possible to see the influence of it in everyday life. But in the equipment where the artificial UV-C radiation wavelength is used as a disinfectant, and probably in the open space, the influence of UV-C could be remarkable. Recently, there has been increasing interest in the food industry to avoid contamination in the food packing process. The global COVID-19 coronavirus pandemic has amplified this interest and has forced authors to run a set of tests with printed plastic parts. This paper analyses the outcome of those tests including two different printing directions and two different surface paints. The study shows that there is considerable influence of UV-C radiation on mechanical and aesthetic properties of 3D SLS printed PA12 parts. However, the influence can be diminished by use of appropriate paints.
Self-driving Shuttle Bus Use Case in City of Tallinn
Authors: Kalda K , Sell R , Soe R-M
Published: May 2021

Autonomous vehicles (AVs) are entering from test areas to the streets, which is one of the key components of smart cities and the future of mobility as a service (Maas). In 2020, two AV services were operated in Tallinn. This paper focuses on one of the services, including how it was set up. The route was set up in Ülemiste City, a tech park with 10,000 people daily working in the area. It connected the offices with the airport and a shopping centre. Autonomous shuttle ise Auto was used for the service (streets with heavy traffic, including some complex crossings). Our findings associated with the Ülemiste experiment in the context of legal requirements set upon autonomous vehicles to be street legal are pointed out. Events that took place during the operation (including an accident) are addressed. Summary of the feedback from clients is presented. Further studies should focus on the extended concept of smart cities with a roadmap for the nearest future.
Multi-layer cyber-physical low-level control solution for mobile robots
Authors: Pikner H , Karjust K
Published: May 2021

Self-driving vehicles and mobile robots are used more and more in public transportation and industrial companies. Multiple experimental platforms, which can be operated in an urban or industrial environment have been developed recently. The key development for robust and safe control of the robot’s operation is relying on the low-level cyber-physical system (CPS). CPS is composed of a collection of tightly integrated computational (cyber) units which are communicating with the physical world. CPS integrates computation and communication aspects with control and monitoring techniques. In this paper, the scientific goals underscore the analysis of the existing state of the art solutions to increase security, safety, and reliability of the multiple experimental platforms.
Effects of Boundary Conditions and Operating Parameters on Temperature Distribution during the Friction Stir Welding Process
Authors: Boukraa M. , Aissani M. , Lebaal N. , Bassir D. , Mataoui A. , Tal Ighil N. , Yue Hao
Published: May 2021

This work deals with a numerical simulation of the friction stir welding FSW process of alloy material AA2195-T8. A 3D transient thermal model for simulating the heat transfer phenomena in the welding phase is applied. In this model, the FSW tool is considered as a circular heat source moving in a rectangular plate having a cooling surface and subjected to non-uniform and non-homogeneous boundary conditions. The thermal problem is solved using the finite element method as part of a Lagrangian formulation. The obtained results allow us to determine the maximum value of the temperature in the Nugget zone of the welded joint. During this process, the thermal cycle and the temperature distribution were determined for different values of the welding process parameters. The obtained numerical results are in good agreement with the one available in the literature.
Analysis of the reciprocal wear testing of Aluminum AA1050 processed by a novel mechanical nanostructuring technique
Authors: Omranpour Babak , Kommel Lembit , Sergejev Fjodor , Ivanisenko Julia , Antonov Maksim , Hernandez-Rodriguez Marco A L , Garcia-Sanchez Edgar
Published: May 2021

This research aims to investigate the impact of a novel technique in mechanical nanostructuring on the wear resistance of materials. This technique with the name of High Pressure Torsion Extrusion (HPTE) can produce bulk nanostructured materials with enhanced mechanical properties. Results of microstructural analysis and microhardness testing showed significant enhancement in materials after HPTE. Microstructural characterization by using Electron Back-Scattered Diffraction (EBSD) method illustrated the presence of Ultra-Fine Grained (UFG) materials in the specimens Analysis of the wear by implementing reciprocal wear testing revealed that the amount of displaced volume markedly decreased after processing. This change in the wear behavior can be explained by referring to the hardness increase and the reduction of plasticity in materials which confined the plastic shearing and diminished the built-up edge around the wear track.
Electric current distribution in thin Ti-Cu base coatings
Authors: Urbaha M , Vorohobovs V , Savkovs K , Fescuks J , Feofanovs V. , Korhs J.
Published: May 2021

The electrical resistivity of thin layer (film, coating) about 5 microns’ thick has been measured by the classical four-point probes method. The layer includes titanium-copper alloy grains up to 5 microns in size. Unexpectedly we encountered a physical phenomenon that spoils the measurements: the fluctuation of measurement results, i.e. the error of measurement may exceed 1000%.. Under certain conditions such crystals may exert some long-range influence leading to tenfold fluctuations of results of measuring the electrical resistivity, despite of the fact that these crystals are evenly distributed and do not create large-size clusters It was found that the relative scatter of measurement results decreases along with the increase of the distance between the electrodes (probes) due to averaging of currents, however, the error decreasing occurs inversely proportional to the logarithm of the distance between the probes. That is why the scatter remains significant at distances between the applied probes thousands times bigger than crystal grains. It decreases much slower than it occurs in case of one dimensional long strip where the error of measurement is simply inversely proportional to the distance between the probes. It creates huge difficulties for measurement of surface resistance. To overcome these difficulties, the method for the statistical proceeding of the non-uniform results of multiple measurements of electrical resistivity in two-dimensional systems has been proposed, which enable to extract information about average surface resistance even from such confusing set of measurements. By help of such statistic the four probe method can be potentially used in industry, for example, for controlling the quality of metal film coatings, used for heating by electrical current for de-icing of aircrafts or wind turbines.

The Paper type: Research paper
Simulation based Feasibility Analysis of Autonomously Movable Robot Arm
Authors: Vaher Kristo , Mahmood Kashif , Otto Tauno , Riives Jyri
Published: May 2021

The use of industrial robots in production is rapidly growing. However, the vast use of industrial robots and implementation of new manufacturing technologies are mostly adopted by large industrial companies. It is due to the nature of the production volume, as robots have a lot of the same kind of work in one specific position in the production process. In smaller companies, where the robots often do not have enough workload in a single specific workplace, the process of robotization has not been so successful. SME-s need a solution where the robot can be moved from one workplace to another in order to utilize the resources like robot arm efficiently. This paper aims to analyse the feasibility for the usage of a robotic arm (a collaborative robot) to serve more than a single production cell intermittently. Production machines are located at particular distance and the movement of the robotic arm between the machines is carried out autonomously with the help of an autonomous mobile robot. Moreover, simulation and 3D visualization were used to conduct and analyse the two different scenarios. Utilization of production equipment assigns as a key performance indicator of the comparison.
Proper use of technical risk assessment tools as an element of the railway safety culture
Authors: Verevkina O I , Veprinyak I A
Published: May 2021

The work is aimed at developing ideas and improving the technical means of risk assessment – the risk matrix. A typical risk matrix defined by regulatory sources is considered. An original approach to evaluating the effectiveness of the risk matrix with associated scales is proposed. The definition of the risk matrix with minimum scale spacing is introduced and the existence of this matrix is proved. It is shown by example that a matrix with minimum scale spacing is a more accurate tool for determining the risk category compared to matrices with wider scale spacing. The problem of finding the parameters of such a matrix from the initial data in a mathematical statement is formulated. One of the branches of the developed simplified algorithm for constructing such a matrix is given.
Improving the electric power quality in the networks adjacent to the railroad traction substations
Authors: Bulatov Yu N , Kryukov A V , Cherepanov A V
Published: May 2021

A significant deterioration in the electric power quality indicators (EPQI) is observed in the 110-220 kV electrical networks, which are directly adjacent to the traction substations of the Trans-Siberian Railway. Such situations are typical of many regions of Siberia and the Far East. The article presents the results of research aimed at improving the electric power quality in the networks adjacent to the traction substations. The simulation algorithms used were based on application of phase coordinates and lattice equivalent circuits. Software tools Matlab and AnyLogic were used to model transition processes and evaluate the effectiveness of the concept of an intelligent electricity quality controlling system. On the basis of the results, technical solutions have been proposed to bring the electric power quality indicators to standard values. It is shown that a comprehensive approach, including the following segments, is needed to address the problem of reduced electric power quality: the use of technology to improve electric power quality indicators; reinforcing 110-220 kV networks that feed traction substations; technologies of smart customization and control of technical means.
Simulation of induced voltages created by the 25 kV traction network across the pipeline in ice melting mode
Authors: Kryukov A V , Cherepanov A V , Kryukov A E , Stepanov A D
Published: May 2021

Long metal structures and facilities can be located along the routes of electrified railways with 25 kV traction networks. A typical example of such facilities is pipelines designed to transport liquid or gaseous products. Due to the electromagnetic effects of electric traction networks, induced voltages can occur on structural parts, which are dangerous for the operating personnel. A set of special measures is needed to improve electrical safety and protect people from the influence of induced voltages. In the context of digitalization of the electric power industry, the choice of such measures requires the use of computer technologies, which can be implemented on the basis of methods and tools for simulation of railway power supply systems developed in Irkutsk State Transport University. The article presents the results of research aimed at the development of computer models designed to determine the electromagnetic effects of electric traction networks on the main ground-laid pipeline in the modes of ice melting.
Electromagnetic influences of autotransformer overvoltage traction networks on pipelines
Authors: Cherepanov A V , Kryukov A E , Kryukov A V
Published: May 2021

The article presents the results of the simulation of the electromagnetic effects of an advanced overvoltage traction network on a steel pipeline with a diameter of 250 mm, laid on the earth’s surface. Due to the electromagnetic imbalance of the traction network, at certain points of the structure, voltages with respect to the ground, dangerous for the maintenance personnel, may arise. In such situations, it is necessary to develop measures to improve electrical safety. In the conditions of digitalization of the electric power industry, the solution to this problem should be based on computer technologies that allow determining the induced stresses arising on the parts of pipelines due to the electromagnetic effect of the traction network. The simulation, performed with the help of the Fazonord software package, showed that at a distance of 100 meters from the railway route to the pipeline, the maximum induced voltage at individual points of the structure can reach 100 V, which is more than one and a half times the permissible value. This must be taken into account when designing advanced traction electric power supply systems in the areas where they are close to the main pipelines.
Tests to estimate the heat rate effect on the flexural durability of transport vehicle gear wheels
Authors: Skutelnik V V , Kolganov S V , Malomyzhev O L
Published: May 2021

The article presents the test results concerning the effect of thermal loads on the flexural durability of gear wheels of transport vehicle high-loaded transmissions. The tests were performed using a universal hydraulic pulsation machine and a thermal loader at five fixed temperature levels from twenty to two hundred degrees Celsius. As a result of the performed tests, a significant dependence of the flexural durability of gear wheels on their thermal state was established. In the expected maximum temperature area, corresponding to the temperature of the low tempering of the gear wheel material, it decreased sharply more than ten times.
The use of energy saving technologies in the service of a rolling stock
Authors: Milovanova E A , Egorova M A
Published: May 2021

The article deals with technical devices used at railway transportation for washing and cleaning of both rolling stock and its parts with a sufficiently large area of coverage of the product range which affect the treated objects or a jet of liquid with a detergent, or involve “bathing” of the object in the washing medium. At the same time the existing technology of cleaning and a design of washing machines do not allow to increase the efficiency of such devices, and the aggressive properties of liquids used in the process are not fully developed. The solution is seen in the intensification of technological processes of washing and cleaning of parts of the rolling stock by rational organization of the structure of the washing liquid flows to improve their performance. The article presents an assessment of the design features of traditional schemes of gas lift devices, the use of devices with forced gas supply for the implemen-tation of technological processes in industrial production.
Using train-passing techniques on the rail network to prevent flooding on rivers
Authors: Haltar L , Dmitrenko A V , Lesnykh E V , Becher S A , Buryanina N S
Published: May 2021

In order to prevent floods on rivers in the presence of a cascade of hydroelectric power plants, it is possible to use the methods of railway transport in the management of their operation, which ensure the prevention of prolonged congestion in the movement of trains due to the accumulation of an increased fleet of wagons on certain landfills. In railway transport, the most dangerous in operational activities are unloading points located mainly on the outskirts of the country or the continent of Eurasia. For railway transport, the most important point in management is the reception of trains during the overhaul of tracks on main lines, mainly located in the central geographic center of the country, located in Kuzbass in Russia. On rivers, in the event of electricity generation, the most dangerous place is the hydroelectric power station located in the middle of an extended river basin. However, the most important and effective points in managing their operation are the upper and lower hydroelectric power plants. The lower hydroelectric power plants provide a quick discharge of excess water, which helps prevent floods. Upper hydroelectric power plants allow one to raise the water level of the cascade of the entire extended river basin at a lower cost.
Diagnostics of tension in long rods with the help of traveling bending waves
Authors: Bardakov V M , Klimov N N , Ermakov A A , Pomerantsev D Yu
Published: May 2021

The article considers the possibility of measuring the tension of long thin structures by measuring the speed of traveling bending waves. Earlier, with the participation of the first two authors of the work, a theoretical consideration of the possibility of determining the stress of a continuous-welded railway track by measuring the velocity of bending waves was carried out. For verification, the velocity of propagation of bending waves was measured, presumably during the compression of a continuous-welded track. This is possible when the temperature of the rails is higher than the laying temperature of the continuous track. In the same consideration, it is taken into account that bending waves exist in an extended product of finite thickness without tension, and the results are presented for the case when the continuous track is in a tensioned state. This consideration takes into account the fact that in a long workpiece of finite thickness there are also bending waves without tension. These waves, unlike the dispersion-free waves of tension, possess dispersion. A method of measuring the speed of these waves is proposed.
Methodology for assessing the competitiveness of options for the direction of the projected railway using SWOT analysis
Authors: Bykov Yu A , Fadeeva V A
Published: May 2021

The article presents a method for assessing the competitiveness of options for the directions of the projected railway at the pre-project stage. The first stage of the method involves the formation of an initial set of alternatives to directions using graph theory. The proposed approach to the formation of options for directions guarantees the consideration of all possible options for connecting the reference points defined by the design assignment. The second stage deals with the formation of an acceptable set of these alternatives using the SWOT analysis, method the use of which allows both quantitatively and qualitatively to assess the impact of internal and external environmental factors on the design object, that is, to take into account the weaknesses and strengths of each direction option, opportunities and threats of the external environment. The fourth stage of the considered method involves the determination of the integrated indicators of economic efficiency recommended for further design options for the direction of the railway.
Considering various conditions during determination of railway curve superelevation
Authors: Beltiukov V P , Andreev A V
Published: May 2021

The calculation of the established railway curve superelevation, until recently, was carried out on the basis of two conditions: the condition of equal wear of both rails and the condition of passenger ride comfort. With the introduction of the Interim guideline on determining the railway curve superelevation and speeds limits in curves, this condition was abolished in favor of a more complex condition for ride comfort. Unfortunately, the condition of ride comfort does not take into account many factors that can influence the determination of the optimal railway curve superelevation. Among such factors are economic factors. In the URRAN methodology, for example, among others, the life cycle cost is considered. For track facilities, it is more relevant to consider the concept of overhaul cycle cost, since it is during the overhaul cycle that the curves are operated. The article proposes, along with the Interim guideline, in which safety factors are considered, to consider the definition of the railway curve superelevation, taking into account the life cycle cost.