Acta Mechanica Slovaca, 2015 (vol. 19), issue 3
Future of Automotive Materials, Technologies and Passenger's SafetyEditorial, Editorial article
Emil Evin
Acta Mechanica Slovaca 2015, 19(3):4
A Construction of H-antimagic Graphs
Mirka Miller, Andrea Semaničová-Feňovčíková
Acta Mechanica Slovaca 2015, 19(3):6-11 | DOI: 10.21496/ams.2015.017 
Let G = (V,E) be a finite simple graph with p vertices and q edges. An edge-covering of G is a family of subgraphs H1,H2,...,Ht such that each edge of E(G) belongs to at least one of the subgraphs Hi, i=1,2,...,t. If every subgraph Hi is isomorphic to a given graph H, then the graph G admits an H-covering. Such a graph G is called (a,d)-H-antimagic if there is a bijection f: VjEg{1,2,...,p+q} such that for all subgraphs H' of G isomorphic to H, the sum of the labels of all the edges and vertices belonging to H' constitutes an arithmetic progression with the initial term a and the common difference d. When f(V)={1,2,...,p}, then G is said to be super...
Experimental Investigation of Mode Shapes of Symmetric Structures
Róbert Huňady, Martin Hagara
Acta Mechanica Slovaca 2015, 19(3):12-17 | DOI: 10.21496/ams.2015.018
Paper deals with experimental determination of modal parameters of symmetric structures which have so-called coupled mode shapes of vibration. These modes usually have almost the same frequencies. This is why it could be difficult to identify them from frequency response functions where their peaks overlap. Main attention is focused on the using of Complex Mode Indicator Function (CMIF) that is able to separate coupled and also closely spaced modes by using singular value decomposition of multiple reference FRF matrix. In the paper there is described a theoretical background of CMIF and its application in spatial domain parameter estimation. Its functionality...
Research on Intensity of Cooling Continuously Cast Steel by Water Nozzles
Marek Velička, René Pyszko, Jiří Burda, Miroslav Příhoda
Acta Mechanica Slovaca 2015, 19(3):18-24 | DOI: 10.21496/ams.2015.019
The article describes heat removal from the hot surface by water. Method of cooling in a secondary zone of continuous casting of steel has a significant influence on a quality of continuously cast products mainly from the point of view of internal and surface defects. For this reason, a physical model of the secondary zone has been developed at the Department of Thermal Engineering, which enables testing of both water and water-air nozzles. During laboratory modelling cooling effects of a nozzle have been expressed by means of two parameters. Most commonly used parameter is spray intensity, infrequently heat transfer coefficient is determined. In comparison...
A Fragmentation Based Approach to the Free Form Surface Milling
Jozef Beňo, Peter Ižol, Miroslav Tomáš, Ján Varga
Acta Mechanica Slovaca 2015, 19(3):26-32 | DOI: 10.21496/ams.2015.020
In this paper, authors performs analysis of the free-form surface milling based on the fragmentation of the design elements which create active surfaces in tool making. Their analysis is based on fragmentation approach which makes the most of combining CAD, modelling and testing objects in tool making as well as selecting of the fragments with parts of free-form surfaces. Examples being introduced in this paper point out that it is volume based fragmentation of free form surfaces which allows to associate CAD design of tooling parts, their modelling and producing in chosen scale as well as testing different milling strategies. Results also showed that...
Experimental Investigation of Dynamic Error for Manipulator Output Link During Its Motion Path Tryout
Yulia Zubkova, Yury Turygin
Acta Mechanica Slovaca 2015, 19(3):34-37 | DOI: 10.21496/ams.2015.021
The paper considers the procedure of carrying out the experimental investigations of the dynamic component of the error for the manipulator output link based on empiric relations obtained experimentally. Results of experimental investigations are presented; they include the empiric relation of evaluating the dynamic characteristics of the manipulator during the tryout of the arbitrary spatial path.
The Stress State in the Three-layer Open Conical Shell During Stability Loss
Edward Tertel, Piotr Kuryło, Władysław Papacz
Acta Mechanica Slovaca 2015, 19(3):38-44 | DOI: 10.21496/ams.2015.022
The paper presents an analysis of the stress state in a sandwich open conical shells during of stability loss. The shells under consideration consist of a lightweight core layer and two face-layers which are load-carrying. The thickness of those faces is assumed to be equal, and the thickness of the core is about 80% of the whole shell thickness. The load carrying faces are made of isotropic, compressible, work-hardening materials. The core layer is assumed to be elastic, incompressible in the normal z direction and it resists transverse shear only. The shell under consideration is loaded by lateral pressure and longitudinal force. Deformation of the...
Magnetocaloric Effect in the Symmetric Spin-1/2 Diamond Chain with Different Landé g - factors of the Ising and Heisenberg Spins
Lucia Gálisová
Acta Mechanica Slovaca 2015, 19(3):46-53 | DOI: 10.21496/ams.2015.023
The symmetric spin-1/2 Ising-Heisenberg diamond chain with different Landé g-factors of the Ising and Heisenberg spins is exactly solved by combining the generalized decoration-iteration transformation and transfer-matrix method. The ground state of the system and the magnetocaloric effect during the adiabatic (de)magnetization are particularly examined. It is evidenced that the considered mixed-spin diamond chain exhibits the enhanced magnetocaloric effect during the adiabatic (de)magnetization in the vicinity of field-induced phase transitions as well as in the zero-field limit when the frustrated phase constitutes the zero-field ground state. The...
Review on Recent Development in Environmental-friendly EDM Techniques
Nishant Kumar Singh, K. K. Singh
Acta Mechanica Slovaca 2015, 19(3):54-66 | DOI: 10.21496/ams.2015.024
The electrical discharge machining (EDM) is unitary of the widely used unconventional machining because of its ability to cut very hard material engendering high dimensional accuracy as well. In thermo-electric process, control sparks generation between electrodes causes material removal; however, application of hydrocarbon oil based dielectric is an issuance of environmental disruption. To rectify this problem, replacement of dielectric is main concerns in EDM research. This paper highlights Dry-EDM, Near-Dry EDM and EDM in water, which is conceived as an environment amiable alteration in the oil EDM process. The work gives a thorough review of Dry,...