Search Results

You are looking at 1 - 10 of 16 items for :

  • Political Economics x
Clear All
Open access

Jelena M. Djoković, Dejan I. Tanikić, Ružica R. Nikolić and Saša M. Kalinović

, particle size, and duration of screening, International Journal of Mineral Processing, Vol. 52, No. 4, 1998, pp. 261 – 272. [7] CHEN, Y. H. - TONG, X.: Modelling screening efficiency with vibrational parameters based on DEM 3D simulation, Mining Science and Technology, Vol. 20, No. 4, 2010, pp. 615 – 620. [8] JIAO, H. G. - LI, J. R. - ZHAO, Y. M.: Test and research on optimum configuration of diameter of screen aperture and incline of screen deck, Coal Preparation Technology, Vol. 35, No. 2, 2007, pp. 1 – 4. [9] UMEHARA, S. - YAMAZAKI, T. - SUGAI, Y.: A

Open access

Maciej Major, Izabela Minda and Izabela Major

, Podręcznik użytkownika, 2014, http://docs.autodesk.com/RSAPRO/2014/PLK/index.html?url=filesROBOT (In Polish). [8] SCI P354: Design of Floors for Vibration: A New Approach The Steel Construction Institute (2007 Edition). [9] PN-EN 1991-1-4:2008, Eurocode 1: Actions on structures, Part 1-4: General actions – wind actions, PKN, Warszawa, 2008, (In Polish).

Open access

Mária Kúdelčíková and Eva Merčiaková

Abstract

In structural dynamics models of mechanical oscillator and vibration analysis are of great importance. In this article motion of mechanical oscillator is modelled using second order linear autonomous differential systems. Stability of such 1 DOF models is investigated with respect to the coefficients of systems. Phase portraits for various cases are displayed and the character of fixed points is described.

Open access

Ján Kortiš, Ľuboš Daniel, Milan Škarupa and Maroš Ďuratný

References [1] DEKÝŠ, V. - ŽMINDÁK, M. – SAPIETOVÁ, A.: The application of modal analysis and condition monitoring for sound and vibration reduction. In: MITECH 2009 - Material Science and Manufacturing Technology, International Scientific Conference, 25.-26. June, Prague, Czech Republic. ISBN 978-80-213-1931-8, p. 61 - 66. [2] NUNO M.M. MAIA, JÚLIO M.M. SILVA: Theoretical and Experimental Modal Analysis. Research Studies Press LTD, July 1998. ISBN 0863802087. [3] KOUROUSSIS, G. - DESCAMPS, T. - BEN FEKIH, L. - VERLINDEN, O.: Application of

Open access

Veronika Valašková and Jozef Vlček

References [1] VALAŠKOVÁ, V.: The comparisons of computational models of pavement due to the dynamic load act. DYN - WIND 2017, MATEC Web of conference, 2017, DOI:10.1051/matecconf/2017107000. [2] FRÝBA, L.: Vibration of Solids and Structures under Moving Loads. ACADEMIA, Praha, Nordhoff International Publishing, Groningen, 1972. [3] MARTINICKÁ, I.: Calculation of Natural Frequencies and Vibration Shapes its own Computational Models of Vehicles Land. Communications and Tracks. Vol. 6 (1 - 2), 2010, pp. 41 – 50 (in Slovak). [4] DANIEL, L

Open access

Ján Kortiš, Ľuboš Daniel, Matúš Farbák, Lukáš Maliar and Milan Škarupa

Abstract

Modern architecture leads to design subtle bridge structures that are more sensitive to increased dynamic loading than the massive ones. This phenomenon can be especially observed on lightweight steel structures such as suspended footbridges. As a result, it is necessary to know precisely its dynamic characteristics, such as natural frequencies, natural shapes and damping of construction. This information can be used for further analysis such as damage detection, system identification, health monitoring, etc. or also for the design of new types of construction. For this purpose, classical modal analysis using trigger load or harmonic vibration exciter in combination with acceleration sensors is used in practice. However, there are many situations where it is not possible to stop the traffic or operation of the bridge. The article presents an experimental measurement of the dynamic parameters of the structure at the operating load using the operational modal analysis.

Open access

Veronika Valašková and Jozef Vlček

References [1] FRÝBA, L.: Vibration of Solids and Structures under Moving Loads. ACADEMIA, Praha, Nordhoff International Publishing, Groningen, 1972. [2] MARTINICKÁ, I.: Calculation of Natural Frequencies and Vibration Shapes its own Computational Models of Vehicles. In: Land Communications and Tracks, 6 (1 - 2), 2010, p. 41 - 50. [3] DANIEL, L. - VALAŠKOVÁ, V. - KORTIŠ, J.: Numerical Simulation of Moving Vehicle across the Obstacle. In: Civil and Environmental Engineering, Vol. 10 (2), 2014, p. 108 - 112. [4] NOVOTNÝ, B. - HANUŠKA, A

Open access

Leonid Diachenko, Andrey Benin, Vladimir Smirnov and Anastasia Diachenko

Abstract

The aim of the work is to improve the methodology for the dynamic computation of simple beam spans during the impact of high-speed trains.

Mathematical simulation utilizing numerical and analytical methods of structural mechanics is used in the research.

The article analyses parameters of the effect of high-speed trains on simple beam spanning bridge structures and suggests a technique of determining of the dynamic index to the live load. Reliability of the proposed methodology is confirmed by results of numerical simulation of high-speed train passage over spans with different speeds. The proposed algorithm of dynamic computation is based on a connection between maximum acceleration of the span in the resonance mode of vibrations and the main factors of stress-strain state. The methodology allows determining maximum and also minimum values of the main efforts in the construction that makes possible to perform endurance tests. It is noted that dynamic additions for the components of the stress-strain state (bending moments, transverse force and vertical deflections) are different. This condition determines the necessity for differentiated approach to evaluation of dynamic coefficients performing design verification of I and II groups of limiting state. The practical importance: the methodology of determining the dynamic coefficients allows making dynamic calculation and determining the main efforts in split beam spans without numerical simulation and direct dynamic analysis that significantly reduces the labour costs for design.

Open access

Ľuboš Daniel, Veronika Valašková and Ján Kortiš

výpočtových modelov vozidiel, In: Pozemné komunikácie a dráhy. ISSN 1336-7501. Roč. 6, č. 1-2 , s. 41-50, 2010. [5] FRÝBA, L.: Vibration of Solids and Structures Under Moving Loads. ACADEMIA, Praha, Nordhoff International Publishing, Groningen, 1972. [6] BENČA, Š.: Výpočtové postupy MKP pri riešení lineárnych úloh mechaniky, Strojnícka fakulta STU v Bratislave, 2005.

Open access

Martin Decký, Matúš Kováč and Peter Kotek

-7100-4251. [4] PAPÁNOVÁ, Z. - PAPÁN, D. - KORTIŠ, J.: Microtremor vibrations in the soil experimental investigation and FEM simulation. In: Communications/Komunikácie. Volume 16, Issue 4, 2014, p. 41-47, ISSN 13354205. [5] MÚČKA, P.: Correlation among Road Unevenness Indicators and Vehicle Vibration Response. In: Journal of Transportation Engineering. Volume 139, issue 8, p. 771-786 DOI: 10.1061/(ASCE)TE.1943-5436.0000558, Published: AUG 1 2013. [6] LEITNER, B.: Fatigue Damage Analysis and Fatigue Life Prediction of Lorry Frame under Random