year 2019

20190304-06
Simulation of the temperature distribution and modelling of molten pool parameters at electron beam drip melting of copper
Tsvetomira Tsonevska, Elena Koleva, Lilyana Koleva, Georgi Mladenov

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In this article quasi steady-state two-dimensional heat model is implemented for the simulation of the temperature distribution in the cast copper ingots through electron beam drip melting. Regression models are estimated ...  read more

20190304-05
Review of hardware-in-the-loop – a hundred years progress in the pseudo-real testing
Nikolay Brayanov, Anna Stoynova

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In the last two decades, the electronics and mechatronics systems became undividable part of human life. With increasing of the number of application fields and functionalities, they became more complex and a lot more efforts ...  read more

20190304-04
Simple PV battery charger without MPPT based on SEPIC converter
Hristo Antchev, Anton Andonov

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This article describes a specific implementation of a SEPIC converter for charging an accumulator battery from a photovoltaic panel and which is characterized by simple control without MPPT. Here are presented some basic mathematical ...  read more

20190304-03
Analysis of non-preemptive priority single-server queueing systems with peaked traffic flows
Seferin Mirtchev, Rossitza Goleva, Dimitar Atamian, Ivan Ganchev

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In this article, single-server priority queueing systems with a peaked arrival process, generally distributed service time and infinite waiting position is analyzed by using the Polya distribution to describe the peaked traffic ...  read more

20190304-02
Spectra of multilayer networks – mathematical foundations, metrics, spectral properties
Mircho J. Mirchev

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This article reviews a generalize approach of network models of complex systems and networks by introducing layers, thus defining multilayer networks. Having the multilayer property on the network model, it can better describe ...  read more

20190304-01
Comparative analysis of the possibilities of building a decentralized control plane of a Software Defined Networks
Jordan Raychev, Diyana Kinaneva, Georgi Hristov, Plamen Zahariev

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The objective of the current paper is to be conducted a comparative analysis of the available possibilities for building a decentralized controller plane of a Software Defined Network (SDN). The SDN networks are an emerging ...  read more

20190102-full
Issue 1-2, 2019

ELECTROTECHNICA & ELECTRONICA E+E

Vol. 54. No 1-2/2019
Monthly scientific and technical journal
Published by:
The Union of Electronics, Electrical Engineering and Telecommunications /CEEC/, BULGARIA

20190102-full

C O N T E N T S

TELECOMMUNICATIONS SCIENCE

Tsvetoslava Kyoseva
Definitions for disruptive innovation in telecommunication technologies 1

Mircho Mirchev
On the spectra of scale-free and small-world networks 9

Lilijana Docheva, Ivo Dochev, Maria Pavlova
Algorithm for software realization of video observation system by means of remote control 17

ELECTRICAL ENGINEERING

Plamen Tzvetkov, Krasimir Galabov, Ivan Kodjabashev


 ...  read more

20190102-06
Analysis of the risks imposed on UAVs in outer space missions
Vasil Vasilev, Emil Vladkov

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The article represents an overview of the different hazards for the operation of Unmanned Aerial Vehicles (UAV) in particular spacecrafts due to the environment in outer space. After a brief history overview of the human inventions ...  read more

20190102-05
Improved wind turbine control using maximum torque per ampere control strategy taking into account the magnetic saturation
Boris Demirkov

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This paper represents an approach for improving the maximum torque per ampere (MTPA) control strategy for permanent magnet synchronous generator (PMSG). The MTPA permits the optimization of the generator stator current for ...  read more

20190102-04
Some features for calibration of analyzers of electric power by power factor
Plamen Tzvetkov, Krasimir Galabov, Ivan Kodjabashev

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In relation to the calibration of analyzers of electric power, the mathematical model of the power factor is represented by its dependence on the phase angle of voltage and current of the first harmonic as well as on the general ...  read more