September 2003, Volume 3, Number 3
SVAČINA, J. The Efficient Method of Ambient Signals Cancellation in EMC Interference Measurements 
KOCUR, D. — ČÍŽOVÁ, J. — MARCHEVSKÝ, S. NonLinear Microstatistic MultiUser Receiver 
MAYER, D. — KROPÍK, P. Theory of the Passive Compensation of a ThreePhase Nonlinear Load 
BOKR, J. — JÁNEŠ, V. Some Interesting Applications of the Karnaugh Map 
SZKUTNIK, J. Logistic Comperative Analysis of Reliability in Regions of a Distribution Company 
NOVITZKÁ, V. Mathematical Language in Programming 
GLADIŠOVÁ, I. — MIHALÍK, J. ContextBased Arithmetic Encoding of Binary Images 
KOVÁČOVÁ, I. — KOVÁČ, D. Safeguard Circuits of Power Semiconductor Parts 
TURÁN, J. — OVSENÍK, Ľ. Laboratory of Fiber Optic Refractometer 
VOKOROKOS, L. Interconnection Netware in Data Flow Architecture 
MACHOVÁ, K. Basic Principles of the Cognitive Algorithms 
Summary: 
Jiří SVAČINA The Efficient Method of Ambient Signals Cancellation in EMC Interference Measurements [full paper] The paper deals with some aspects of EMC interference signal measurements in the presence of undesired ambient signals that appear mainly by an open field test site measurement. The method for efficient ambients cancellation is described, and discussed in the article from theoretical, as from practical point of view. The method, which is in the form of special hardware/software utilities already implemented in some modern electromagnetic interference (EMI) receivers, is based on ambient signals storing in an internal receiver memory and then on their “subtracting” from actual measured signals. Results of this concept depend first of all on the character of actual ambients signals, and on their time and frequency stability. After the theoretical background of the concept is stated, its effectiveness was checked in series of EMI measurements by using the EMI Spectrum Receiver from the Seaward Ltd. in the frequency range from 9 kHz to 1000 MHz. By this, we have used various types of simulated as well as real existing ambient signals and various modes of EMI receiver. The cancellation of ambients was tested for continuous harmonic signal, for continuous square wave ambient signal, and for signal of broadband white noise character. The simultaneous treatment of these types of signals was also investigated. All tests were executed under the PeakDetection mode of the EMI receiver, some of their also by using the QuasiPeak detection mode. Our measurement demonstrated, that the “subtraction” effect is more effective in QuasiPeak mode measurement, as in Peak detector mode. Simultaneously, the accuracy of the cancellation increases with decreasing of the measuring frequency span. Thus, our practical experiences show, that by taking a proper measuring process, the obtained results are very good, and the cancellation of undesired ambients can be made very
effectively.

Dušan KOCUR  Jana ČÍŽOVÁ  Stanislav MARCHEVSKÝ NonLinear Microstatistic MultiUser Receiver [full paper] In this paper, the microstatistic multiuser detection receiver (MSFMUD) will be introduced. The output of the MSFMUD is taken as the sign of the multichannel nonlinear transformation of the output of a bank of matched filters (BMF). In the case of the MSFMUD, this transformation is done by multichannel conventional microstatistic filter (MCMF). Because the MCMF theory has not been available, a method of the timeinvariant MCMF design is developed in this paper, too.

Daniel MAYER  Petr KROPÍK Theory of the Passive Compensation of a ThreePhase Nonlinear Load [full paper] An algorithm is described for defining passive parameters of twopoles RLC, with whose help it is possible to compensate a threephase load. The method is valid for sinusoidal or nonsinusoidal, balanced or unbalanced threephase power system with linear or nonlinear load. The problem is formed as an optimisation problem for minimizing losses in line. Given calculation method is illustrated by three numerical problems. It is possible to modify this method even for solution of other power engineering problems, e.g. for design of filters enabling increased quality of transmitted electric energy by suppressing unwanted higher harmonics in network.

Josef BOKR  Vlastimil JÁNEŠ Some Interesting Applications of the Karnaugh Map [full paper] The article describes a construction of a Boolean (Zhegalkin) polynomial with respect to a given Boolean function, and vice versa. It also presents a simple way of writing symmetric Boolean functions that allow easy construction of minimal disjunctive normal
forms.

Jerzy SZKUTNIK Logistic Comperative Analysis of Reliability in Regions of a Distribution Company [full paper] In the report, I depicted the new outlook on the problem of reliability of the network. It is the logistic point of view, taking into consideration the form of the terrain and infrastructure of the communication network, which is crucial for the time needed for the emergency forces to get to the place of breakdown. The presented logistic ratios describing reliability can constitute an additional tool aimed at decreasing the time of shortage of energy supply. The report contains also analyses conducted on the basis of data of the chosen distribution company. The final part of the research is correlation analysis being a basis for presentation of general dependencies.

Valerie NOVITZKÁ Mathematical Language in Programming [full paper] In our paper we present a dealing with a mathematical language as a basis for formulating different kinds of specifications for a general problem solving by computers. We concentrate on the mathematical basis of data abstractions as program units with mathematically defined meanings and we concern with the development of programs from requirements to results.

Iveta GLADIŠOVÁ  Ján MIHALÍK ContextBased Arithmetic Encoding of Binary Images [full paper] This paper deals with an approach to the compression of binary images. Specifically, the approaach utilises a contextbased arithmetic encoding method. The coding and modeling aspects are treated separately. Model statistics are studied from stationary and stationary adaptive assumptions This efficient binary contextbased arithmetic code is relatively simple to implement because it avoids the multiplication operation. In the last part of the paper there are analyzes and investigation effeciency of the methods of contextbased arithmetic encoding for given images.

Irena KOVÁČOVÁ  Dobroslav KOVÁČ Safeguard Circuits of Power Semiconductor Parts [full paper] The paper deals with the most important electrical limitation parameters of power semiconductor parts. Some recomended safeguard circuits are described and also is given the review about possibilities of the extension of it‘s above mentioned maximum elektrical parameters.

Ján TURÁN  Ľuboš OVSENÍK Laboratory of Fiber Optic Refractometer [full paper] Using fiber optics and microoptics technologies was designed an innovative fiber optic index of refraction transducer that has unique properties. On the base of this transducer a laboratory equipment type fiber optic refractometer was developed for liquid index of refraction measurements. Such refractometer may be used for medical, pharmaceutical, industrial fluid, petrochemical, plastic, food, and beverage industry applications. For example, it may be used for measuring the concentrations of aqueous solutions: as the concentration or density of a solute increase, the refractive index increases proportionately. The paper describes development work related to design of laboratory type fiber optic refractometer and describes experiments to evaluation of its basic properties.

Liberios VOKOROKOS Interconnection Netware in Data Flow Architecture [full paper] Dataflow (DF) computer architectures are based on the DF computing model where program instructions are executed when corresponding operands (data) are enabled. From several DF computing models dynamic models belong to the most significant ones. The dynamic DF models enable parallel execution of some operators in dependence on the number of operands, which are available for the execution. The nodes of the corresponding DF graph, by means of which the computing process is represented, can be created dynamically during the execution.

Kristína MACHOVÁ Basic Principles of the Cognitive Algorithms [full paper] This paper focuses on basic principles of learning algorithm design. It presents various principles employed in known learning algorithms dealing with different representations of concept definitions. It discusses pros and cons of application of the presented basic principles in relation with classification task. The focus is also on systematization of algorithm election or design in several steps. First, a problem / learning task is analyzed. Next, those of basic principles are selected, witch match the given learning task requirements. Lastly, a general algorithm is designed in the form, which can be transformed into a selected programming language without difficulties.
