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Košice, Slovakia

Hudak R.,Technical University of Kosice | Zivcak J.,Technical University of Kosice | Toth T.,Technical University of Kosice | Majernik J.,University in Kosice | Lisy M.,CEIT Biomedical Engineering
Studies in Computational Intelligence | Year: 2015

Development of additive technologies and biocompatible materials facilitated their use in the custom-made implants manufacture. Verification of custommade implants manufactured using the additive manufacturing technologies is the key task to be fulfilled prior to the clinical application of an implant. It consists of parameters verification within individual steps, from a software design, through manufacturing, surface finishing, up to finalization of a medical product. The article presents possible uses of a 3D printing and the computed tomography (Metrotom 1500, Carl Zeiss, Germany) for the verification of selected parameters of customized implants manufactured using the Direct Metal Laser Sintering (DMLS) technology with the EOSINTM280 equipment (EOS GmbH, Germany) from the biocompatible titanium alloy Ti-6Al-4V (Grade 5). The article describes the possibilities of the computed tomography use in the verification of implant shapes and external dimensions, as well as internal structure. The internal structure means the implant porosity assessment. © Springer International Publishing Switzerland 2016.

Torok C.,University in Kosice
Kybernetika | Year: 2013

Interpolating and approximating polynomials have been living separately more than two centuries. Our aim is to propose a general parametric regression model that incorporates both interpolation and approximation. The paper introduces first a new r-point transformation that yields a function with a simpler geometrical structure than the original function. It uses r ≥ 2 reference points and decreases the polynomial degree by r-1. Then a general representation of polynomials is proposed based on r ≥ 1 reference points. The two-part model, which is suited to piecewise approximation, consist of an ordinary least squares polynomial regression and a reparameterized one. The later is the central component where the key role is played by the reference points. It is constructed based on the proposed representation of polynomials that is derived using the r-point transformation Tr(x). The resulting polynomial passes through r reference points and the other points approximates. Appropriately chosen reference points ensure quasi smooth transition between the two components and decrease the dimension of the LS normal matrix. We show that the model provides estimates with such statistical properties as consistency and asymptotic normality.

Jurko J.,University in Kosice
Advanced Materials Research | Year: 2013

The basic hypothesis of this article focuses on the study changes in mechanical properties of stainless steels ELC X01Cr18Ni10Ti under surface finish when drilling. The problem of drilling holes with diameter D=3 to 10 mm resides in the fact that 30 to 40% of these holes do not comply with prescribed requested requirements1. This article presents the results of experiments focusing on the study of the damage process in helical drills with diameter d=6.0 mm when drilling into austenitic stainless steel ELC X01Cr18Ni10Ti. This study also includes an analysis of accompanying phenomena in the cutting zone by measuring some selected parameters. © (2013) Trans Tech Publications, Switzerland.

Sedlak V.,University in Kosice
International Journal of Mechanics | Year: 2015

The mining activity influence on the environment belongs to the most negative industrial influences. As a result of underground mining of the mineral deposits in the surface creates the subsidence trough, i.e. caving zone which could be dangerous for any movement of people in this zone. Character and size of the mining subsidence on the surface depends mainly on the geotectonic ratios of rock massif above the mined out area. Knowing the extent of the subsidence trough in mining areas is determining to prevent the entry of people into these dangerous zones. Conditioning factors to establish the extent of the movement of the earth's surface above the mined out area are a geodetic way surveyed deformation vectors which can be derived from the processing of measurements at monitoring stations based on these mining tangent territories. The limits of undermined regions in many cases equal to isolines connected so called break points occurred in the front of the subsidence borders. The theory for the estimation of polynomial break points in the case of subsidence analysis is presented. The theory was developed as a part of the kinematics analysis procedures for the evaluation of the magnesite deposit in the suburb of Kosice- Bankov on the northern outskirts of the city of Kosice in the eastern Slovakia. The subsurface abandoned mine Kosice-Bankov is located in the immediate vicinity of the recreational and tourist zone in the northern suburb of the city of Kosice. Some numerical and graphical results from the break points estimation in the magnesite deposit Kosice-Bankov are presented. The obtained results from the abandoned mining area Kosice-Bankov were transferred into GIS for the needs of the local governments in order to conduct the reclamation of this mining landscape. © 2015, North Atlantic University Union. All rights reserved.

Valko-Rokytovska M.,University in Kosice | Hubkova B.,University in Kosice | Birkova A.,University in Kosice | Marekova M.,University in Kosice
Spectroscopy Letters | Year: 2014

The fluorescent analysis of multicomponent biological materials is very difficult. To model a proper system to characterize their quality is therefore indispensable. Influence of mixture composition was studied in a mixture of three naturally occurring diagnostically important urine metabolites: indoxyl sulfate, 5-hydroxyindole-3-acetic acid, and 3-methoxy-4-hydroxymandelic acid. Relationships between these compounds were monitored by measurement of synchronous fluorescence spectrum matrix. The fluorescence emission of 3-methoxy-4-hydroxymandelic acid when combined with indoxyl sulfate, or even with 5-hydroxyindole-3-acetic acid, was utilized for the excitation of indoxyl sulfate or 5-hydroxyindole-3-acetic acid, resulting in an increase in their fluorescence and in a decrease in 3-methoxy-4-hydroxymandelic acid fluorescence intensity. © 2015 Taylor & Francis Group, LLC.

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