June 2004, Volume 4, Number 2
Summary: 
Ján TURÁN  Ľuboš OVSENÍK  Ján TURÁN, Jr. Invariant Pattern Recognition System Using RT and GMDH [full paper] The proposed paper gives the results of the development work related to design pattern recognition system based on Application of fast translation invariant Rapid Transform (RT) and GMDH. The system was implemented as a software package on PC and tested with identification of classes of real objects. Experimental results are given for applying the proposed invariant pattern recognition system to recognition of Nativity Symbols, Informative Symbols and Cuneiform Writings corrupted by noise.

Václav MENTLÍK The Aspects and Perspective Views of the Diagnostics of Electric Devices [full paper] The diagnostics is an indispensable part of all stages of electrical engineering industry. The diagnostics is a source of information, which also accompanies a product in the exploatation. This information influences on the construction based of the failure analysis regressively. The diagnostics with the results of running checks gives information about the diagnostic object's property and provides beddings for the predictive data. The ONLINE diagnostics, which monitors the object continuously during its work, is essential for important and expensive objects. It is necessary to construct the diagnostic systems (diagnostic tools) with respect to the deposition ability and the economic demand. The structural approach to the solved problems is very perspective, because it has bigger deposition ability and it provides more complex information than the current phenomenological approach.

Ľudmila MACEKOVÁ  Stanislav MARCHEVSKÝ A New Image and Video Quality Criterion [full paper] The well known quality criteria of images and video as MSE or MAE are not corresponding sufficiently with the quality perceived by human visual system (HVS). HVS is mostly sensitive to the structural character of images and to structural errors, too. The new criterion of quality respects this aspect and can also be considered universal, because of its value not exceeding one, which is the best quality (identity actually) and the others values represent the worse quality.

Zoran H. PERIC  Srdjan M. BOGOSAVLJEVIC Asymptotic Analysis of Optimal Unrestricted Polar Quantization [full paper] The motivation for this work is maintaining high accuracy of phase information that is required for some applications such as interferometry and polarimetry, polar quantization techniques as well as their applications in areas such as computer holography, discrete Fourier transform encoding, and image processing. In this paper the simple and complete asymptotically analysis is given for a nonuniform polar quantizer with respect to the meansquare error (MSE) i.e. granular distortion (Dg). Granular (support) region of a quantizer is considered as the interval where quantization errors are small, or at least bounded; that's why it is greater challenge to include the overload distortion in estimation procedure of a quantizer ([1]). The support region for scalar quantizers has been found in [1] by minimization of the total distortion D, which is a combination of granular (Dg) and overload (Do) distortions, D=Do + Dg. Swaszek and Ku [2] didn't consider the problem of finding the optimal maximal amplitude, socalled, support region. The goal of this paper is solving the quantization problem in case of nonuniform polar quantizer and finding the corresponding support region. We also gave the conditions for optimum of the polar quantizer and optimal compressor function. The equation for Dq (opt) is given in a closed form. The construction procedure is given for i.i.d Gaussian source.

Ján KOLLÁR Process Functional Properties and Aspect Language [full paper] In this paper we present essential characteristics of aspectoriented approach to programming as provided in aspect programming languages. Then we demodularize a programming structure of a process functional sample to a type definition module and the own definition module, using purely functional case. Adding environment variables to the type definition module we show that there are possible resources to the computational reflection using process functional paradigm in a welldefined variable environment. We also identify the weaknesses and possible directions in further development of objectoriented process functional language to extend it to an aspect oriented
language.

Miloš DRUTAROVSKÝ  Martin ŠIMKA Custom FPGA Cryptographic Blocks for Reconfigurable Embedded Nios Processor [full paper] This paper introduces two custom blocks for Nios reconfigurable embedded processor implemented on Altera Field Programmable Gate Arrays (FPGAs). When operations like modular multiplication and modular exponentiation of long integers or other complex algebraic functions are performed on a generalpurpose processor they usually consume a lot of processor resources and execution times are not satisfactory. A solution of this problem lies in development of custom coprocessors. The algebraic coprocessor for Montgomery Multiplication (MM) makes possible a fast execution of modular multiplication with large numbers that can be used in several public key cryptographic algorithms. A True Random Number Generator (TRNG) enhances an application of the Nios processor in cryptographic protocols. Until now only few implementations of TRNG on FPGA have been presented in literature. We describe a custom TRNG implementation based on a recently proposed method that reliably extracts intrinsic randomness from lowjitter clock signals synthesized by onchip FPGA analog PLLs. Both peripheral blocks are connected to the Nios processor through Altera Avalon bus that directly supports scalable connection and different sources of the clock signal. In this way we can optimally use the resources of Altera FPGAs and implement designs customisable with regard to available area resources and desired level of security or timing constraints. Proposed solutions significantly improve security and computational power of System on a Chip (SoC) embedded cryptographic applications based on the Nios processor.

Pavla HEJTMÁNKOVÁ  Jan ŠKORPIL Voltage in Electric Power System with High Photo Voltaic Cells Penetration [full paper] Small, distributed generation (DG) technologies such as microturbines, photovoltaic (PV) and fuel cells are gaining wide interest because of rapid advances in technologies. The deployment of these generation units on distribution networks could potentially lower the cost of power delivery by placing energy sources nearer to the demand centres. The capacity of the devices ranges from 1 kW to 2 MW in power level.

Jan CVEJN Effective Way of Overriding C++ Operators for Matrix Operations [full paper] The article describes an effective way how to create a library for manipulating matrices in a similar manner as if they were numbers in programming language C++. Although overriding arithmetic operators for manipulating classes such as vectors and matrices seems to be a standard procedure in C++, there occur serious problems when performance aspects are taken into account. The main disadvantage consists in frequent allocating and deallocating memory, which can significantly slow down evaluating arithmetic expressions. In the article an implementation is described that eliminates redundant memory allocations and enables using overridden operators for effective evaluating matrix expressions.

Miloslava TESAŘOVÁ Using VoltageDip Matrices for Counting of Voltage Dips in Power Systems [full paper] Voltage dips (sags), mainly caused by remote short circuits, are generally considered as the serious power quality problem. The most used calculation method for the prediction of the number of voltage dips in the power system is called the method of fault positions. The method is based on systematic calculation of shortcircuit faults spread through the power system. By using shortcircuit analysis algorithm the voltage dip matrices should be formed.

Matúš PLEVA  Jozef JUHÁR  Anton ČIŽMÁR About Development and Evaluation of Multilingual Database for Automatic Broadcast News Transcription Systems [full paper] This paper deals with the problem of broadcast news transcription, segmentation algorithms, training database, and related topics. The automatic transcription of broadcast news is an attractive application of speech technology. To support research in this domain LDC has created the Hub4 American Broadcast News corpus. As there are large differences between the American and European national broadcasts, institutions collaborating in the European action COST278 Spoken Language Interaction in Telecommunication joined together to compile an European Broadcast News Database.

Ondrej KARPIŠ Partial Suppressing of Disturbing Signals Using Modified Notch Filter [full paper] Classical notch filter with zeros on the unit circle completely eliminates disturbing signal component from frequency spectrum of input signal. Ideally it should be able to remove only that part of given frequency component which was not present in original (unimpaired) signal. Modified discrete notch filter which partially suppress disturbing harmonic signal is proposed in this work. Determination of notch depth is based on average power of disturbing signal and frequency components in its neighbourhood. Computer simulations confirm proper function of the designed filter. Filter is able to adapt notch depth to abrupt changes of disturbing signal amplitude.

Marek HIČÁR Crane Uplifting with Burden Weight Observer [full paper] Crane uplifting with burden weight observer is very useful to use in combination with uplift, crab and bridge motion with cooperated transfer of their parameters: burden weight, rope length and crab and bridge position.
