This thesis deals with numerical analyses of electromagnetic fields on small aircraft with composite parts as an innovative way for assessment of their inherent protection against electromagnetic effects of outside environment in all development stages. It is concentrated for procedures of creation of geometrically and materially complex models for simulating calculations in the time as well as frequency domains, execution of the simulations itself and comparisons of results between the internal electromagnetic calculations and executed experimental tests. Achieved results were verified on a simplified reference model of aircraft's fuselage and two aircraft prototypes VUT100 and EV-55 of the company Evektor, spol. s r. o.

This master thesis deals with design and realization of multistage electromagnetic accelerating device (gun) and possibilities to increase its effectivity. This work contains a simulation of a magnetic circuit and designs of each components, inclusive of control circuits. Reached effectivity will be measured by appropriate methods.

This master thesis deals with the problem of the origin and expression of partial discharges in dielectric materials. In the thesis the theoretical foundations, types and parameters of partial discharges are described. In particular, it deals with UHF (ultra high freqeuncy) electromagnetic radiation using UHF method of partial discharge detection. It also deals with the partial discharge UHF signal simulation. The development of UHF sensor systems for partial discharges requires a dive that can simulate them as accurately as possible. Furthermore, a workplace was designed for simulation and detection of partial discharges and processing of their time and frequency characteristics.

The doctoral thesis deals with a non-destructive testing method (NDT) designed to evaluate the uniformity of distribution and determination of the concentration of steel fibres in steel fiber reinforced concrete (SFRC). At present, no non-destructive method is available in the field of diagnostics of building structures to assess the concentration and the homogeneity of SFRC. The Institute of Building Testing (SZK FAST BUT Brno) has several diagnostic devices, but their utility for the evaluation of selected parameters of SFRC has not proven during the research activity. This knowledge led to the design of a new measuring instrument in cooperation with the Institute of Theoretical and Experimental Electrical Engineering of the Faculty of Electrical Engineering and Communication (UTEE FEKT BUT in Brno) and the methodology for evaluation of these parameters. The proposed NDT method has been experimentally tested and verified for its utility for the evaluation of SFRC in building practice.

This work deals with a mobile signal propagation in electromagnetic wave form in a real environment of city microcell. The electromagnetic wave passing through the city environment is affected by many kinds of mechanism. It includes especially diffraction along vertical edges of buildings, diffraction across building roofs and buildings or ground refraction. These mechanisms are time variable. If we want to predicate them, we have to use sort of approached model. For an experimental part of this work, the Berg’s recursive model with a possibility of path loses or signal level prediction in a selected microcellular system is chosen. The software for a cellular network coverage is created on the basis of this fact. Its advantage is a possibility of up to five base stations placing and many kinds of settings, e.g. operating frequency, base station transmitting power, base and mobile station antennas height etc. There is a possibility of system GSM 900, GSM 1800 or UMTS choice. The Berg’s recursive model features are checked by simulations on experimental and real maps of build-up area.

This master thesis gives overview of non-destructive tests of concrete and provides detailed information concerning the acoustic and electromagnetic emission during monitoring of concrete failure. Conducted loading tests of plain concrete specimens are described in the thesis together with the performed numerical simulations of these tests in the software ATENA. The simulation results of concrete failure are analysed in detail and compared with the experimental results recording failure processes with the help of acoustic and electromagnetic emission. The majority of simulation results in software ATENA 3D show good agreement with the recorded data.

This thesis deals with modifications to the construction of vibration-to-electricity energy converter, which is one of possible solutions to problem of sustainable and stable energy source for wireless sensor supply. Upon the exploration of the present state of this problem, new construction of generator is proposed. The aim of this proposal is to enhance the existing generator properties with respect to retention of its dimensions and its weight. Results obtained by simulations of model with proposed parameters are presented and analysed.

Disertace popisuje současné problémy v certifikaci malých letadel, které by se měly v budoucnu řešit numerickým modelováním. Tento postup má zefektivnit návrh a zlevnit certifikaci letadel. Práce je úzce spjata s projektem HIRF-SE, který se problematikou certifikace letadel numerickými metodami zabývá. Podstatná část práce je věnována popisu dvou modulů pro platformu HIRF-SE: řešič BUTFE založený na metodě konečných prvků v časové oblasti a budicí nástroj BUTFE_EXC. Práce popisuje řešení pohlcujících okrajových podmínek, modelování disperzních a anizotropních materiálů a aproximaci tenkých drátů. Speciální pozornost je věnována řešení aproximace tenkých drátů s ostrými ohyby, jejíž současná formulace způsobuje překryvy mezi jednotlivými segmenty drátu.

The proposed dissertation thesis contains an analysis of conditions on the boundary between layers having varied electromagnetic properties. The research is performed using consistent theoretical derivation of analytical formulas, and the underlying problem is considered also in view of multiple boundaries including the effect of the propagation of electromagnetic waves having different instantaneous speed. The author presents a survey and formulation of the basic characteristics of methods used for electromagnetic wave propagation analysis; in this respect, special emphasis is placed on radial models. The processing of the topic involved the designing and verification (using a set of different, layered planar materials) of algorithms to analyze the electromagnetic field components. The algorithm was assembled to enable simple evaluation of all components of the electromagnetic field in relation to the speed of the wave propagation in a heterogeneous environment. The proposed algorithms are compared by means of different numerical methods for the modelling of electromagnetic waves on the boundary between materials; moreover, electromagnetic field components in common points of the model were also subject to comparison. When in conjunction with tools facilitating the analysis of material response to the source of a continuous signal, the algorithms constitute a supplementary instrument for the design of a layered material. Such design enables the realization of, for example, recoilless plane, recoilless transition between different types of environment, and filters for both optical and radio frequencies.

Using circuit breakers as devices for protecting the circuit, equipment, property, and not least the people is an important part of the generation, transmission and distribution of electricity. This puts high demands on the design of complex devices such as circuit breakers. To ensure proper function is one of many parts and that is the trip unit. Trip unit is used to evaluate the current flowing through the breaker and respond to undesirable overcurrent. For these reasons, this work deals with electromagnetic analysis - specifically thermal magnetic trip unit. The focus will be on improving the actual situation and finding more suitable design solutions.