The present work reports the length?weight relationships (LWR) for four ornamental fish species from the middle Negro River basin, Amazonas, Brazil. The r2 value ranged from 0.810 to 0.941 and values of b varied from 2.346 to 3.442. These results…

This paper uses dynamic general equilibrium and computational methods, inspired by the multi-sector growth model structure in Stephen Turnovsky's work, to develop a theory that unifies two of the traditional explanations of structural change: sector-biased technical change and non-homothetic preferences.…

Four-Wave Mixing (FWM) in semiconductor optical amplifiers is an attrative mechanism for wavelenght coversion in wavelenght-division multiplexed (WDM) systems since it provides modulation format and bit rate transparency over wide tuning ranges. A series of systems experiments evaluating several aspects…

In the past the reliability of the telecommunication systems was evaluated on the simple assumption of the independence of elements. Comuputation of steady - state series - system availability depends on specific assumptions made about the non failed items during…

The contribution deals with the use of computers in the technical subject teaching. It shows more common view on the possibilities of the computer use. It also shows that there is a lin to concrete conditions of the use of…

Energy saving effects connected with use of energy accumulator on board of tram vehicle instead of substation are presented. Differences in results regarding weak and strong power supply system when taking into account energy losses and energy recuperation are pointed…

The paper analyses features of traction transformer desing. Secondary windings of the transformer are utilized as a choke of an locomotive input filter at DC supplying system. Different ways of connections of the secondary windings coils are compared, reachable inductances…

The article states main principles of dimensioning of traction supply stations DC traction current system. it also provides detailed results of the traction rectifier substation Ostrava-Svinov load measurement. The measured valued are subsequently used for calculation of characteristic coefficients, whitch…

The paper present aspects of DC electric traction system influence on electric energetic system. Study is based on modeling and simulation of electrified railway line. After simulation, there was performed analysis of energy quality, whitch using results of simulation and…

This paper deals with a decentralised power active filter control based on the separated computation of reference current for each active filter operating under determinated harmonic frequency. The basic principle of such controlled active filter is explained. It is shown…