In this paper, proposed steganalytic method utilized for the detection of secret message is based on extraction of statistical fea-tures from cover and stego images in JPEG file format together with calibration technique. The steganalyzer concept uses Support Vector Machines (SVM) classification or Bayes classifier for training a model that is later used by the same steganalyzer in order to identify between a clean (cover) and stego image. The aim of the paper was to compare detection accuracy (ACR) of the trained models for two types of classifiers: Support Vector Machines and Bayes classifier. In this paper, five models created between cover and stego images (images obtained by nsF5, Model Based 1, Model Based 2, Modulo Histogram Fitting with Dead Zone and Per-tubed Quantization steganographic method) was tested.

In this paper, we will present a method for through-the-wall localisation of targets in 3D space by ultra-wideband (UWB) radar. The targets are moving or static uncooperative human beings and the localisation is based on the time-of-arrival (TOA) measurement. The presented method is based on the use of a specific antenna array layout, which simplifies the problem of the 3D multilateration method to the solution of two 2D localisation problems. Through-the-wall as well as the line-of-sight measurements were done for both static and moving person scenarios and the results of the selected scenarios are described in this paper.

The goal of this article is to analyse, design, implement and test different ways of evaluating and visualizing logs from intrusion detection system (IDS). For the main objective of this work it was necessary to study the ways in which it will be possible to carry out data visualization recorded in the IDS database. It was necessary to design and implement evaluation, imaging and visualization logs of intrusions recorded in a computer network security system. The work will therefore bring more comfortable option to read large amounts of technical messages to humans. Such a person does not have to have knowledge of the system, which used to display visualized data in depth – the person should just be able to interpret the visualization displayed on a computer screen.

Identification of initial commutation angle belongs to the basic routines at the commissioning of industrial drives with permanent magnet synchronous machine. This paper deals with problem of commutation angle offset determination. Two methods are described and simulated in detail. The first method is based on application of a DC voltage and the second one is based on the use of the current controllers. Both methods use rotor movement to reach defined position. Simulation and experimental results are included providing mutual comparison of these methods.

Insulation system is one of the most important part of electrical devices. This insulation system is usually composed by solid part and liquid part. Oil impregnated insulation paper is used in transformers for many years. There are a lot of factors which have significant influence on the insulation system during the life time of electrical devices. Temperature is one of the factors which has strong influence on condition of oil paper insulation. This paper is focused on measuring of electrophysical properties of oil paper as relative permittivity, AC breakdown voltage and polarization index of insulation before and after thermal ageing. Vegetable oil paper insulation and mineral oil paper insulation were investigated and analyzed.

The paper presents the brief overview of the design and implementation of visual programming tool for visual creation of data flow graph (DFG) and its automatic transformation to the program code for computer with the data flow computation control that is designed at the Department of Computers and Informatics of the Faculty of Electrical Engineering and Informatics, Technical University of Košice.

Mechanical forces impact three-phase line conducted by large currents. These forces cause higher safety requirements. This paper deals with possibilities of lowering these forces by shielding of the conductors. The numerical method of calculation of the time function of forces, when conductors are shielded by ferromagnetic jackets and conducted by symmetrical three-phase system currents, is stated. The calculation of eddy currents density induced into shielding jackets is stated further; eddy currents cause the heating of shielding jackets. An illustrative example shows that properly designed shielding is able to strongly reduce the magnitude of forces while the eddy current losses density is very low is the heating is subtle.

When two or more lines are running parallel to each other, mutual impedances between the lines influence the voltage and current profile measured by protective relays installed on each line. In this article the behavior of a distance relay on a double circuit transmission line is analyzed and simulated using Matlab/Simulink software. This article discusses about the influence of mutual impedance on impedance measured by distance protection and shows possibility of compensation these adverse effects using different compensation factors. Double-circuit 400 kV overhead lines supplied from two sides were used for this purpose. Phase-to-earth faults in different configurations of parallel lines in power systems were simulated on this network.

Besides cryptography, the great attention is paid to the steganography, which is considered not only the science but also the art of the concealed communication. In steganography, the information is hidden within another piece of information, called stegomedia. This paper presents a new data hiding technique based on steganographic algorithms that is hiding information into vector images. The paper briefly introduces this technique and evaluates the benefits and drawbacks of the proposed approach.

The paper deals with a new method of design of digital pulse generator, which is specially designed for multiphase converters. The advantage of this control method lies in its applicability to the microcontrollers. The generator is capable of generating the PWM pulses for a variable number of legs in the range of 1-10. In the article, the results from 6 legs connection are presented. By the utilization of the several legs, the generator can generate pulses with phase shift and frequency of 50 kHz. The size of the phase shift depends on the number of legs. The paper describes the functions of the individual parts of the generator, which are shown schematically. The simulations and experimental models were built and measured to verify the theoretical assumptions. The paper contains also the PCB design and practical construction notes.

This paper presents the speed control of 4 phase 8/6 Switched Reluctance Motor drive with PWM controller. The motor is fed from an Asymmetrical bridge converter, because of its fault tolerant capability and all the phases are independently excited. The Hall sensors provided in the motor provide signals corresponding to the position of the rotor. The speed is controlled by varying the duty ratio of the PWM controller. The pulses to the IGBT switches are generated using a Digital Signal Processor. The SRM drive with PWM controller is simulated in MATLAB/SIMULINK and also experimentally implemented at no load & partial load. The waveforms of the PWM signals and phase currents are captured by means of Digital storage oscilloscope and compared with the simulation results.