December 2005, Volume 5, Number 4

KOVÁČOVÁ, I., KAŇUCH, J., KOVÁČ, D.:
The EMC of Electrical Systems – Galvanic Coupling  (Part II.)

Jovanovic, Z., Dankovic, B., Antic, D.:
Reliability Estimation of the Discrete-Time Control Systems with Random Parameters

ROUBAL, J., AUGUSTA, P., HAVLENA, V.:
A Brief Introduction to Control Design Demonstrated on LaboratoryModel Servo DR300 - AMIRA

BOUZEBOUDJA, H., CHAKER, A., ALLALI, A., NAAMA, B.:
Economic Dispatch Solution Using a Real-Coded Genetic Algorithm

GREGA, M., ČOPJAN, Ľ., MARCHEVSKÝ, S., BENČO, S.:
Possibility of Using Network Simulator (NS-2) for Modeling Satellite Networks

JANOTA, A., ZAHRADNÍK, J., SPALEK, J.:
Attributes Selection for Licence Plate Recognition Based on Decision Trees

Matiaško, K., Zaitseva, E., Kovalik, Š.:
The Algorithm for Calculation of the Dynamic Reliability Indices in Multi-State Systems

Fedor, P., Perduková, D.:
A Simple Fuzzy Controller Structure

Bouri, S., Zeblah, A., Ghoraf, A., Hadjeri, S., Hamdaoui, H.:
Ant Colony Optimization to Shunt Capacitor Allocation in Radial Distribution Systems

SOBOTA, B.:
Modelling of Hand Surface in Virtual-Reality System

Summary:
KOVÁČOVÁ, I., KAŇUCH, J., KOVÁČ, D.:
The EMC of Electrical Systems – Galvanic Coupling  (Part II.) [full paper]

This papers deals with the analysis of the electromagnetic compatibility (EMC) – galvanic coupling problems focused on the area of the power electrical systems. The description of galvanic coupling problem is divided into two separate parts according to the length of common conductors or the working frequency. The first part (PART I.) deals with the galvanic coupling problem of concentrated parameter circuits, such with short common conductors or processed signals with low working frequency. The second one (PART II.) analyzes the same problem for circuits with distributed parameters, such that have long common conductors or processed signals with high working frequency. For detailed problem investigation a mathematical analysis, computer simulation method and verification measuring are used, too.


Jovanovic, Z., Dankovic, B., Antic, D.:
Reliability Estimation of the Discrete-Time Control Systems with Random Parameters [full paper]

This paper deals with a method for reliability estimation of the discrete-control systems with random parameters. The problem of probability stability and a method for probability stability estimation of the arbitrary order systems are also considered.


ROUBAL, J., AUGUSTA, P., HAVLENA, V.:
A Brief Introduction to Control Design Demonstrated on Laboratory Model Servo DR300 - AMIRA [full paper]

This paper is written as a motivation for the students who are beginning to study the control engineering. Therefore, the below mentioned references are introduced with regard to this fact. The paper shortly presents the procedure of the control design, including a description of a system, an identification of its parameters, a simple and an advanced controller design. The controller design procedures are illustrated on the laboratory model servomechanism DR300 – AMIRA, which is held in the laboratory of control theory K26, Department of Control Engineering, Faculty of Electrical Engineering, Czech Technical University in Prague áhttp://www.cvut.cz/ñ.


BOUZEBOUDJA, H., CHAKER, A., ALLALI, A., NAAMA, B.:
Economic Dispatch Solution Using a Real-Coded Genetic Algorithm [full paper]

In this paper, an efficient and practical real-coded genetic algorithms (RCGAs) has been proposed for solving the economic dispatch problem. The objective is to minimize the total generation fuel cost and keep the power flows within the security limits. 
For each problem of optimization in genetic algorithms(GAs) there are a large number of possible encodings. Although binary representation is usually applied to power optimisation problems, in this letter we use a RCGAs , witch is a modified GAs employing real valued vectors for representation of the chromosomes. The use of real valued representation in the GAs has a number of advantages in numerical function optimization over binary encoding [1]. The efficiency of the GAs is increased as there is no need to convert chromosomes to the binary type, less memory is required, there is no loss in precision by discretization to binary or other values, and there is greater freedom to use different genetic operators.
A non-uniform arithmetic crossover operator was introduced into the RCGAs [1][2].
We used a non-uniform arithmetic crossover operator produces a complimentary pair of linear combinations produced from random proportions of the parents.
The non-uniform mutation operator is used to inject new genetic material into the population and it is applied to each new structure individually[2]. A given mutation involves randomly altering each gene with a small probability.
The proposed technique improves the quality of the solution and speed of convergence of the algorithm. The RCGAs developed is compared with a binary-coded genetic algorithm (BCGAs) and classical optimisation technique of Quasi-Newton (Broyden-Fletcher-Goldfarb-Shanno) [3].
The proposed approach has been tested on the IEEE 25-bus system [4].


GREGA, M., ČOPJAN, Ľ., MARCHEVSKÝ, S., BENČO, S.:
Possibility of Using Network Simulator (NS-2) for Modeling Satellite Networks [full paper]

This paper answers to the question if is possible to simulate satellite networks in Network Simulator (NS-2). We describe its functionality such as types of nodes, kinds of satellite links and handoffs. Also are presented two real satellite networks, Iridium and Teledesic, compared their parameters and simulation results. Numerical and graphical outputs are presented to show how satellite networks work. 


JANOTA, A., ZAHRADNÍK, J., SPALEK, J.:
Attributes Selection for Licence Plate Recognition Based on Decision Trees [full paper]

The paper deals with an image-based recognition system, which captures, interprets, records, and processes the image of a license plate for use in a variety of ITS applications. Such a system can save money by collecting and processing vehicle data without human intervention. Motorists are then allowed to pass toll plazas or weigh stations without stopping, which can save their time and prevent occurrence of congestions. Helping control access to secured areas or assisting in law enforcement can also improve safety and security. In different references this technology is also referred as Automatic Vehicle Identification, Car Plate Recognition, Automatic Number Plate Recognition, Car Plate Reader or Optical Character Recognition for Cars. 
The paper discusses a concept of the Licence-Plate Recognition system consisting of several modules that are in different stages of development. It focuses on processing of images with only one vehicle captured. The system is based on decision trees created using inductive tree algorithms. After brief outline of the system the main attention is paid to selection and detailed description of attributes used to build a decision tree. The paper includes an algorithm used to find holes and arcs in the characters. Totally 32 principal attribute types are explained. Some of them are used several time in an analogical way, thus the final decision tree of the discussed system prototype contains 77 nodes. The system has been prototyped using C++ and designed for recognition of Slovak-style license plates. Some of introductory procedures (image input and selection of area with licence plate in the image) are still performed manually and in future can be fully automated.


Matiaško, K., Zaitseva, E., Kovalik, Š.:<
The Algorithm for Calculation of the Dynamic Reliability Indices in Multi-State Systems [full paper]

A lot of complex sytems (Operation Systems, Database systems, Distributed Systems, Information Systems, etc. ) is possible describe, form the point of view of reliability, like the Multi-State Systems. The Multi-State System is investigated in this paper as an object of reliability analysis. In this case system and its component may experience more than two states of reliability as opposed to the Binary System (the system and its components are allowed to have only two possible states: completed failure and perfect functioning). The mathematical model of the Multi-State System is improved. We examine the system to allow a different number of discrete states for the system and for each component and propose to apply Dynamic Reliability Indices for investigation of this system. These indices estimate influence upon the Multi-State System reliability a change of the system component state.


Fedor, P., Perduková, D.:
A Simple Fuzzy Controller Structure [full paper]

The paper deals with the development of a simple fuzzy controller structure. Compared to the common structure it does not require information on the derivation of the controlled system output variable because obtaining of information on derivation is often difficult or too costly. A possible fuzzy regulator structure only requires information about the output variable and its integrals for its operation. The properties of the proposed controller have been verified on two types of fuzzy controllers: Mandami fuzzy controller and Sugeno fuzzy controller. The presented controller shows dynamic properties suitable for all the fundamental electric drive control requirements. In view of speed control the presented controller has a PI character but from point of view of position control the presented controller has a PD charakter. Its properties are verified on the basic operational states of a drive with a separately excited DC motor by simulation with the MATLAB programming package. The methodology of its design can also be applied to other types of controlled systems.


Bouri, S., Zeblah, A., Ghoraf, A., Hadjeri, S., Hamdaoui, H.:
Ant Colony Optimization to Shunt Capacitor Allocation in Radial Distribution Systems [full paper]

This paper presents an ant colony approach optimization to shunt capacitor placement on distribution systems under capacitor switching constraints. The optimum capacitor allocation solution is found for the system of feeders fed through their transformer and not for any individual feeder. The main advantages due to capacitor installation, such as system capacity release and reduction of overall power and energy losses are considered. The capacitor allocation constraints due to capacitor-switching transients are taken into account. These constraints are extremely important if pole-mounted capacitors are used together with a station capacitor bank. An ant colony algorithm is used as an optimization tool. An illustrative example for Algerian network is presented.


SOBOTA, B.:
Modelling of Hand Surface in Virtual-Reality System [full paper]

This paper deals with the virtual-reality system and it is focused to kinematic and statokinetic and visualisation subsystems. Main stream of this paper describes a modelling of human hand surface. Model of human hand is based on skeleton model with using of complex geometric transformations a NURBS for surface representation. 
The paper is divided to three parts. First part describes skeleton model of human hand. Every finger is approximated with linear construction and every construction contains rotation nodes and edges with fixed length. Second part contains description of surface model. Surface is assigned for every edge (bone) of skeleton model. This surface has cylinder form and is constructed from two parts: upper and bottom part. Every part is defined by NURBS plane. One chapter describes association between edge (finger bone) of skeleton model and appropriate control points of NURBS plane. Thumb is solved separately. In the last part are described advantages, disadvantages and usage of this solution. This part contains the example of output from program implementation.


 

Publisher

    Faculty of Electrical Engineering and Informatics, Technical University of Košice, Slovak Republic

    Reg. No.: EV 2921/09,
    thematic group B1,
    ISSN 1335-8243
    The editorial board assumes no responsibility for damages suffered due to use of acts, methods, products, instructions for use or other ideas published by the article authors whatsoever.
EAN 9771335824005