Communications - Scientific Letters of the University of Zilina, 1999 (vol. 1), issue 1
Articles
The New Possibilities of Dynamic Compensation and Regeneration of Energy in Electric Traction
Branislav Dobrucky, Alena Otcenasova, Michal Pokorny, Rastislav Tabacek
Communications - Scientific Letters of the University of Zilina 1999, 1(1):5-12 | DOI: 10.26552/com.C.1999.1.5-12 
The paper presents dynamic compensation, harmonics filtration and regeneration of symmetrical non-harmonic / non-linear loads in energetic systems. The new original thought uses Clarke's orthogonal transform for creation of state-space vector of investigated quantities and its decomposition into real- and imaginary components. The acquisition and control circuitry of the filter can then handle fast dynamic changes of the load, due to six-side symmetry of state-space vector in the complex domain. The analysis and computation of the load's active power / current should be completed within one fourth of the period for single-phase system and one sixth...
Using Fuzzy Logic in the Critical Process Controlling
Juraj Spalek, Monika Molnarova
Communications - Scientific Letters of the University of Zilina 1999, 1(1):13-17 | DOI: 10.26552/com.C.1999.1.13-17
In this paper the advantages of fuzzy logic used for two - channel systems output comparison in safety - related critical applications have been presented. The paper deals with the design of the fuzzy logic - based comparator that compares the data of traction vehicle velocity in target braking process and its optimisation using the ANFIS method. Some failures of the system in Matlab - Simulink environment have been simulated. The result is the analysis of ailures consequences from the point of system safety.
A Method of Projecting of Electric Drive for the Traction Vehicle with wn Asynchronous Motor
Bernard Bednarik, Milan Pospisil, Jiri Drabek, Jan Valuska
Communications - Scientific Letters of the University of Zilina 1999, 1(1):18-30 | DOI: 10.26552/com.C.1999.1.18-30
This contribution describes a computing method of the continuous rating for the traction vehicle with induction traction motors. A method of specifying probable mechanical and electrical parameters and characteristics of the asynchronous motor as well as relationships and methods for calculation of probable traction characteristics of the vehicle will be shown.
Internal Combustion Engines at the Turn of Millennia
Jerzy Merkisz, Vladimir Hlavna
Communications - Scientific Letters of the University of Zilina 1999, 1(1):31-38 | DOI: 10.26552/com.C.1999.1.31-38
Trends in the development of piston internal combustion engines in a view of tightened ecological regulations (exhaust and noise emissions, fuel consumption) have been presented in this paper. Possibilities and ways of engine design adjustments, both gasoline and diesel type (light and heavy duty), that were undertaken to fulfil the present as well as the expected standards of exhaust toxicity have been discussed as well.
Experience in Railway Track Testing for Validation of Theoretical Dynamic Analysis
Milan Moravcik
Communications - Scientific Letters of the University of Zilina 1999, 1(1):39-51 | DOI: 10.26552/com.C.1999.1.39-51
The objective of this paper is to present some experimental approaches in dynamic testing of the railway track structure. The load - deflection track characteristics are particularly important in the design, in the evaluation of serviceability of concrete-sleepers tracks, and to improviding data for computer modelling of the track dynamic behaviour and the dynamic vehicle/track interaction analyses. Thus, results of theoretical dynamic analyses of the track structure must be verified and compared with obtained experimental results. The herein presented track testing for validation of dynamic analyses can give many useful indications concerning the...
Theoretical and Experimental Study of Composite Beams
Jan Bujnak, Monika Simalova
Communications - Scientific Letters of the University of Zilina 1999, 1(1):52-56 | DOI: 10.26552/com.C.1999.1.52-56
The paper discusses the traditional structural analysis of composite structures and actual limit-state design as well as the efficient elasto-plastic computer model. The results of the alternative analytical study are compared with test results on the composite beam specimens.
Pavements from the Point of View of Future Requirements of Road Transport
Jan Corej, Martin Decky
Communications - Scientific Letters of the University of Zilina 1999, 1(1):57-64 | DOI: 10.26552/com.C.1999.1.57-64
Pavement is a very important part of road construction. The authors of this paper deal with problems which are to be solved not only at present but also in the future. They are mainly the following questions: improvement of functional properties of pavement surface, suitable construction parts, computing methods and quality of different pavement layers.
Modernisation of Railway Junctions
Ivan Malicek
Communications - Scientific Letters of the University of Zilina 1999, 1(1):65-68 | DOI: 10.26552/com.C.1999.1.65-68
Modernisation of railway transport is not possible without complex modernisation of railway stations and junctions. This modernisation will actually mean their preparation for implementation of the main tasks of railway for the future. The paper presents some of the most necessary arrangements, without which the railway will not be able to compete with other modes of transport.
Quality Culture the Key to Quality Improvement
Jan Stefanik
Communications - Scientific Letters of the University of Zilina 1999, 1(1):69-72 | DOI: 10.26552/com.C.1999.1.69-72
Quality culture is the total of the collective or shared learning of quality-related values as the organization develops its capacity to survive in its external environment and to manage its own internal affairs.
Fast Way to Quality
Stanislav Kmet, Pavol Magner
Communications - Scientific Letters of the University of Zilina 1999, 1(1):73-77 | DOI: 10.26552/com.C.1999.1.73-77
Every age has its popular words - today, these are quality and information. Information systems are growing everywhere around us. These information activities bring profit to companies.Let's search for optimal information behaviour. The licensed software ISOxPERT accessible on our market is able to secure the information about the market, competitors, subsuppliers, products and services.
Work-Based Learning: Injection or Infection?
Neville R. Hunt, Shamim Z. Warwick
Communications - Scientific Letters of the University of Zilina 1999, 1(1):78-84 | DOI: 10.26552/com.C.1999.1.78-84
This paper considers the role that universities can play in supporting lifelong learning by the adaptation of teaching methods to provide in-company education directed at specific roles and tasks. It considers the ways work-based learning (WBL) as a teaching methodology can inject new theories, concepts and models directly into industry. It balances the positive benefits of WBL with a critical appraisal of its drawbacks, particularly with respect to the threat of relaxation of academic standards and the dangers of gradual infection of academic integrity across all delivery methods. It looks at the opportunities for WBL in the Slovak Republic and concludes...
Education of CA Technologies in Mechanical Engineering Study
Viera Poppeova, Nadezda Cubonova, Juraj Uricek
Communications - Scientific Letters of the University of Zilina 1999, 1(1):85-89 | DOI: 10.26552/com.C.1999.1.85-89
Process of education in study branch Production Systems Equipped with Robots and Manipulators is mainly oriented towards the areas of Numerically Controlled Machines and Computer Aided Technologies, Computer Aided Design and Computer Aided Manufacturing Systems in Mechanical Engineering.
Language as Means of Communication
Anna Hlavnova
Communications - Scientific Letters of the University of Zilina 1999, 1(1):90-93 | DOI: 10.26552/com.C.1999.1.90-93
The paper deals with the question of languages as means of communication. It analyses language instruction in institutions of higher learning. Areas of special interest are mentioned and some ways leading to the integration of all language skills into instruction are suggested.