Communications - Scientific Letters of the University of Zilina, 2017 (vol. 19), issue 2A
Articles
Smart Industry Requires Fast Response from Research to Innovation
Milan Gregor, Stefan Medvecky, Patrik Grznar, Tomas Gregor
Communications - Scientific Letters of the University of Zilina 2017, 19(11):3-9 | DOI: 10.26552/com.C.2017.2A.3-9 
Factories of the Future (FoF) gradually advance towards reality. The theoretical concepts leave research laboratories and quickly find their field in industry. This paper introduces Smart Factory issues. The authors in its first part summarized information from research and main trends in the area of advanced manufacturing systems. Second part of the paper shows the results from authors own research conducted in co-operation of Mechanical Engineering Faculty of the University of Zilina and its Spin Off, The Central European Institute of Technology - CEIT, a.s. The paper shows chosen results from implementation of research results in innovation of internal...
Adaptive Logistics Management and Optimization through Artificial Intelligence
Branislav Micieta, Jolanta Staszewska, Vladimira Binasova, Jozef Hercko
Communications - Scientific Letters of the University of Zilina 2017, 19(11):10-14 | DOI: 10.26552/com.C.2017.2A.10-14
Adaptive logistics management can be reached using artificial intelligence and optimization processes. The paper deals with adaptive logistics management in order to allow direct communication between logistics management systems and logistics facilities, machines, robots and mobile robot system using AI and adaptive behavior in logistics processes. In addition, the paper discusses development trends in adaptive logistics processes and new features such as holonic systems of autonomic logistics management.
Verification of Shrinkage Formation in Steel Ingots in Laboratory Conditions
Jan Moravec, Jan Langa, Pavel Solfronk
Communications - Scientific Letters of the University of Zilina 2017, 19(11):15-22 | DOI: 10.26552/com.C.2017.2A.15-22
The paper describes the process of ingot casting from a modelling material into a special ingot mould made for these tests. As a modelling material we chose stearin (tristearin, glycerol tristearate), which proved to be suitable for this kind of laboratory tests. Casting was done in two ways - using a vertical ingot mould and a horizontal one. Observation of the ingot after solidification confirmed the fact that the cavity filling took place in the laminar flow of the melt.
The Innovative Design of Rolling Stock Brake Elements
Juraj Gerlici, Mykola Gorbunov, Kateryna Kravchenko, Olga Prosvirova, Tomas Lack
Communications - Scientific Letters of the University of Zilina 2017, 19(11):23-28 | DOI: 10.26552/com.C.2017.2A.23-28
The paper deals with traffic safety in railway transport. The influence of the work of the braking system friction elements on braking performance is evaluated. The temperature in the pad-on-disc or pad-on-wheels contact has significant influence on the friction brake elements. Important factor in achieving maximum braking power is the control of the temperature in the contact. The analysis of methods and designs for heat dissipation from contact friction elements is carried out. The effect of ventilation channels of disc brakes on the vehicle running resistance is considered. The technical solutions for temperature control in friction elements during...
About Creation of Bogie of the Freight Car
Juraj Gerlici, Mykola Gorbunov, Olena Nozhenko, Vaclav Pistek, Sergiy Kara, Tomas Lack, Kostiantyn Kravchenko
Communications - Scientific Letters of the University of Zilina 2017, 19(11):29-35 | DOI: 10.26552/com.C.2017.2A.29-35
Analyses of the operating problems of freight car bogies are carried out, as well as the reasons resulting in deterioration of the dynamic characteristics of modern bogies are specified. The main directions of modernization of existing bogie structures and the creation of fundamentally new designs of the bogies are planned. It is reasonable to design a bogie based on hire and using the multifunctional modules and pre-stressed structures. It would allow to reduce the weight of bogies, improve their strength and dynamic properties, and increase the speed of movement. Design solutions for improving the strength and dynamic properties of bogies implementing...
The Issue of Balancing Internal Combustion Engines with Non-Conventional Crank Mechanism
Peter Baran, Pavol Kukuca, Dalibor Barta, Robert Labuda, Pawel Drozdiel, Saugirdas Pukalskas
Communications - Scientific Letters of the University of Zilina 2017, 19(11):36-41 | DOI: 10.26552/com.C.2017.2A.36-41
It is possible to use not only classical crank mechanisms, but also non-conventional mechanisms in design of combustion engines. Balancing these mechanisms is a fundamental prerequisite of their proper function and long life. The concept of measuring system for balancing analysis is applied to a special type of piston machines with wobble mechanism. First part of the paper deals with description of FIK nonconventional mechanism (named after the inventors Fitz, Istenik, Kukuca), main parts and its functionality. Second part deals with measuring system, which is designed to measure dynamic parameters of non-conventional piston mechanism. The measuring...
Simulation of Real Driving Cycles of Electric Cars in Laboratory Conditions
Lubos Kucera, Tomas Gajdosik, Igor Gajdac, Martin Mruzek, Maria Tomasikova
Communications - Scientific Letters of the University of Zilina 2017, 19(11):42-47 | DOI: 10.26552/com.C.2017.2A.42-47
This article is focused on the area of research and development of vehicles with electric drive. The paper presents the results of research based on real electric vehicle EDISON EV as the real traffic in laboratory conditions reflecting. The analysis of special driving style was created in order to increase electric vehicle range.
Simulation of Planetary Gearbox
Maria Tomasikova, Tomas Gajdosik, Michal Lukac, Frantisek Brumercik
Communications - Scientific Letters of the University of Zilina 2017, 19(11):48-53 | DOI: 10.26552/com.C.2017.2A.48-53
This article is about calculation of planetary gearbox. The gearbox consists of two planetary gears - input and output. The gearbox model is created in Simscape Driveline. The model contains Simscape blocks which represent a gear box, clutch, ideal torque source and many others blocks. At the end we compare our results of simulation with calculations.
Applications of Modern Technologies in the Production of Aircraft Propeller Prototype
Marek Bistak, Stefan Medvecky, Eva Gajdosova, Marian Dzimko, Stanislav Gramblicka, Robert Kohar, Marian Stopka, Jan Steininger, Slavomir Hrcek, Michal Tropp, Frantisek Brumercik
Communications - Scientific Letters of the University of Zilina 2017, 19(11):54-59 | DOI: 10.26552/com.C.2017.2A.54-59
In the field of engineering relatively new designs and manufacturing processes are constantly emerging. These changes are often seen in designing and manufacturing of prototypes or in single part production. We decided to analyse an aircraft propeller prototype using modern technologies. Existing aircraft blade design was converted to digital models which were analysed.
Modelling and Experimental Analysis of Noise Transmission through Wall of a Railway Vehicle
Peter Zvolensky, Juraj Grencik, Lubomir Kasiar, Peter Volna, Riccardo Licciardello
Communications - Scientific Letters of the University of Zilina 2017, 19(11):60-67 | DOI: 10.26552/com.C.2017.2A.60-67
The paper presents results of a grant research project dealing with acoustic properties of the walls and floor of a railway passenger coach investigated by means of the experimental analysis of noise produced during train runs and corresponding simulations. In the research, conditions and theoretical approaches for possible reconstructions of walls and floor of the railway passenger coach using new fibrous-microstructure acoustic materials were defined, with the aim of increasing the sound reduction index. The properties of the proposed materials were compared in terms of the acoustic energy transfer through the porous microstructure calculated by...
Approaches to the Computer Vision System Proposal on Purposes of Objects Recognition within the Human-Robot Shared Workspace Collaboration
Alexander Rengevic, Darina Kumicakova, Ivan Kuric, Vladimír Tlach, Pawel Drozdziel
Communications - Scientific Letters of the University of Zilina 2017, 19(11):68-73 | DOI: 10.26552/com.C.2017.2A.68-73
The article deals with the present topic of solution of the tasks of a safe cooperation between human and robot within industrial applications. The attention is aimed at the utilization of state-in-art devices of computer vision and related methods of object recognition within the monitored zone of the laboratory of automated assembly. The article presents some steps of the computer vision system design with focus on the suitable sensors selection and experimental verification of their parameters for demands of monitoring the specified safety zones. The designed computer vision system is one of the elements of the complex safety system that is in the...
Electrochemical Characteristics of Austenitic Stainless Steel in Mixed Chloride - Molybdate Solutions
Viera Zatkalikova, Lenka Markovicova, Anna Wrobel-Knysak
Communications - Scientific Letters of the University of Zilina 2017, 19(11):74-78 | DOI: 10.26552/com.C.2017.2A.74-78
The effect of molybdate addition to chloride solutions on resistance of AISI 316Ti stainless steel to pitting corrosion was studied. Potentiodynamic polarization tests were performed in 1 M and 0.1 M chloride acidified solutions with various additions of sodium molybdate at room temperature. The presented results compare the effect of molybdate anions on quality of passive film (expressed by the pitting potential) in both chloride solutions. The pitting potential increases with the increase of inhibitor concentration. The inhibitive effect of molybdate ions is stronger in chloride solution of lower aggressiveness (0.1M).
Monte Carlo Comparison of the Methods for Estimating the Weibull Distribution Parameters - Wind Speed Application
Ivana Pobocikova, Zuzana Sedliackova, Maria Michalkova, Florence George
Communications - Scientific Letters of the University of Zilina 2017, 19(11):79-86 | DOI: 10.26552/com.C.2017.2A.79-86
Wind energy is considered one of the most significant alternative energy sources for electrical energy production. The most important factor for modelling wind energy is the wind speed. The two-parameter Weibull distribution is commonly used for modelling wind speed. Its parameters play an important role in the wind energy applications and so it is important to choose the best method for the estimation of these parameters. In this paper we investigate and compare six different methods for estimating the Weibull distribution parameters. The methods we considered are the maximum likelihood method, the method of moments, the empirical method, the power...
Finite Element Modeling Piezoelectric Materials under Thermal Loads with Application for Quantum Dots
Milan Zmindak, Pavol Novak, Peter Bishay
Communications - Scientific Letters of the University of Zilina 2017, 19(11):87-93 | DOI: 10.26552/com.C.2017.2A.87-93
Significant research has been done in the analysis of properties of quantum dots over the previous decade. A 3D finite element model is developed to analyze quantum dots (QD) under static thermal loads. The lattice mismatch between the quantum dot and the piezoelectric matrix is created by different thermal properties of materials at enhanced temperature of this electronic structure. The fully coupled thermo-piezoelectricity is applied to the analysis of the problem. Commercial FEM software ANSYS was used for analysis. Finite element numerical results are given for the dot with a cubic shape. Numerical results for the InAs/GaAs QD nanostructure show...
The Impact of Bark Content in Wood Pellets on Emission Production During Combustion in Small Heat Source
Michal Holubcik, Jozef Jandacka, Matej Palacka, Nikola Kantova, Ewa Jachniak, Petr Pavlik
Communications - Scientific Letters of the University of Zilina 2017, 19(11):94-100 | DOI: 10.26552/com.C.2017.2A.94-100
The combustion of biomass is relatively complicated. To minimize the emission production it is necessary to ensure the optimal setting of combustion process. The article deals with the impact of bark content in wood biomass on performance and emission parameters of a small heat source. The increasing content of bark in wood biomass changes its chemical composition and parameters, namely its net calorific value, ash content, ash fusion temperature and others. During experiments samples of wood pellets made from spruce having 1, 2, 5 and 10 percent bark content together with a reference sample without any bark content were burned. The samples were burned...
Digital Radiography Corrosion Mapping on Gas Pipelines
Radoslav Konar, Milos Mician, Miroslav Bucha, Peter Vrzgula, Ivo Hlavaty
Communications - Scientific Letters of the University of Zilina 2017, 19(11):101-105 | DOI: 10.26552/com.C.2017.2A.101-105
Digital radiography (DR) is a powerful technique that can be used in non-destructive testing for identification of internal or external defects and corrosion mapping. New generation of digital flat panel detectors become more and more competitive to film detectors, however the transition from film to digital radiography is not always the best choice for every NDT organization especially from the point of view of investments. The paper introduces the application of digital corrosive radiography mapping on gas pipelines using a portable flat panel detector. The experimental part is focused on determining the residual thickness of the pipelines in service.
Application of Memetic Algorithms in Multi-Criteria Structural Optimization
Peter Pechac, Milan Saga, Peter Weis, Tomasz Domanski, Marcin Kubiak
Communications - Scientific Letters of the University of Zilina 2017, 19(11):106-111 | DOI: 10.26552/com.C.2017.2A.106-111
The goal of this paper is to present new innovative algorithms for discrete structural optimization of problems involving multi-criteria objective function, which contains stress, displacement and frequency constraints. The algorithm is tested on a shell finite element structure, whose optimization variables are geometrical parameters and shell thicknesses. Performance of memetic algorithm will be compared with genetic algorithm.
Investigation of Stress Status in the Micro-Space of Surface and Subsurface Layer
Andrej Czan, Michal Sajgalik, Lucia Zauskova, Robert Cep, Zdenka Rysava, Vitor Luiz Sordi
Communications - Scientific Letters of the University of Zilina 2017, 19(11):112-116 | DOI: 10.26552/com.C.2017.2A.112-116
One of main issues when evaluating or analysing quality and functional properties of work-piece is identification of status of residual stress. Every treatment or machining process generates residual stress in the surface and subsurface layers of the material structure. The residual stress has a large influence on the functional properties of the components. The article is focused on the method of triaxial measurement of residual stress after machining the surface of sample by high feed milling technology. Significance of triaxial measuring is the capability of measuring in different angles so it is possible to acquire stress tensor containing normal...
Intensification of Heat Transport from the Furnace to Heat Accumulator through a Phase Change
Milan Malcho, Stanislav Gavlas, Peter Hrabovsky, Roman Banovcan, Tomas Puchor, Lukasz Orman, Tadeas Ochodek
Communications - Scientific Letters of the University of Zilina 2017, 19(11):117-123 | DOI: 10.26552/com.C.2017.2A.117-123
In the article the authors analyse the process of heat transport from the furnace to a heat accumulator through a phase change of a heat carrier (working substance), design a construction and describe measurements done on experimental equipment. This type of heat transport is substantially more intense that the one in natural or forced convection and takes place without generating the working substance flow with a drive aggregate. Another advantage is heat accumulation control according to a pre-set temperature of an accumulator through an automatic flow control of the working substance in a condensation phase. The equipment consists of an autonomous...
Molybdenum Sheet Metal Test Device
Ronald Bastovansky, Michal Tropp, Michal Lukac, Frantisek Brumercik
Communications - Scientific Letters of the University of Zilina 2017, 19(11):124-127 | DOI: 10.26552/com.C.2017.2A.124-127
The paper presents the construction of a device that allows processing the Baosteel/Sanchez experiment. The experiment simulates the brake ribs by deep drawing of the molybdenum sheet metal.
Errata: Communications - Scientific Letters of the Zilina, vol. 19, No. 2, 2017, "Incorporating Bicycles into Urban Mobility: An Opportunity for Sustainable Development", pp. 68-73.
Carlos Lopez-Escolano, Angel Pueyo Campos, Sergio Valdivielso Pardos, Eva Nedeliakova, Vladimira Stefancova
Communications - Scientific Letters of the University of Zilina 2017, 19(11):128 | DOI: 10.26552/com.C.2017.2A.128
Errata: Communications - Scientific Letters of the Zilina, vol. 19, No. 2, 2017, "Incorporating Bicycles into Urban Mobility: An Opportunity for Sustainable Development", pp. 68-73. The proper quotations [12] and [19] should be referred to as follows: [12] PUEYO CAMPOS, A., LOPEZ-ESCOLANO, C., DIESTE HERNANDEZ, J.: Moving Towards Sustainable Mobility in Zaragoza (Spain): The Bicycle as a Mode of Urban Transport. Consensus, Paralysis and Conflicts in an Effervescent Model [L'Evolution de Saragosse vers la mobilite durable: Le elo comme mode de transport urbain. Consensus, paralysie et conflits d'un modele en effervescence]. Sud-Ouest Europeen, 40, 2015,...