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Numerical Modeling of Periodical Structures
Nešpor, Dušan ; Bartušek, Karel (referee) ; Brančík, Lubomír (referee) ; Fiala, Pavel (advisor)
The thesis discusses the dynamic electromagnetic field on periodic structures. The author focuses on three principal types of resonant structures, considering their application possibilities. In general, these types can be individually defined as follows: materials exhibiting a negative refractive index of the incident electromagnetic wave; structures with gradual changes in impedance, characterised by their usability as reflectionless surfaces; and periodic structures able to conveniently shape the magnetic field distribution. Materials of the third group within the above-shown short list facilitate the fabrication of magnetoinductive lenses for nuclear magnetic resonance. The presented analysis of the properties of periodic resonant structures is mainly based on numerical models utilising the finite element method, and this approach is combined with both the derivation of the corresponding analytical relations and an experimental measurement of the non-radiating component of the electromagnetic field. The thesis includes a physical description of the basic elements of periodic resonant structures. Physical properties of the elements were examined in detail via numerical analysis. In the course of the research, the data acquired through this analysis and the related experimental measurement enabled the author to propose a method for optimising the most widely used resonant structures. Moreover, several new versions of resonant elements, structures, and fabrication techniques were also designed. The results obtained from the numerical analyses carried out to examine the central physical properties of the fabricated structure samples were all verified via the designed method for measuring the non-radiating component of the magnetic field.
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Design and Realization of Metamaterial
Kovaľová, Soňa ; Drexler, Petr (referee) ; Nešpor, Dušan (advisor)
The thesis discusses the design of periodic resonant structures, studying of their impact to surrounding electromagnetic field and realisation of magnetoinductive lens with potential application in nuclear magnetic resonance imaging. Frequency tuning of structure by variation of different parameters is described. The finite element method in Ansys HFSS was used to analyse the properties of designed structures.
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The Design and Realisation of Metamaterial
Kovaľová, Soňa
The work discusses periodic resonant structures with negative permeability (metamaterials) as an improvement of NMR tomograph resolution. The aim of work is to design and adjust magnetoinductive lens for application in nuclear magnetic resonance imaging. The software Ansys HFSS was used for finite element method analysis of designed structure.
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Design and Realization of Metamaterial
Kovaľová, Soňa ; Drexler, Petr (referee) ; Nešpor, Dušan (advisor)
The thesis discusses the design of periodic resonant structures, studying of their impact to surrounding electromagnetic field and realisation of magnetoinductive lens with potential application in nuclear magnetic resonance imaging. Frequency tuning of structure by variation of different parameters is described. The finite element method in Ansys HFSS was used to analyse the properties of designed structures.
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Numerical Modeling of Periodical Structures
Nešpor, Dušan ; Bartušek, Karel (referee) ; Brančík, Lubomír (referee) ; Fiala, Pavel (advisor)
The thesis discusses the dynamic electromagnetic field on periodic structures. The author focuses on three principal types of resonant structures, considering their application possibilities. In general, these types can be individually defined as follows: materials exhibiting a negative refractive index of the incident electromagnetic wave; structures with gradual changes in impedance, characterised by their usability as reflectionless surfaces; and periodic structures able to conveniently shape the magnetic field distribution. Materials of the third group within the above-shown short list facilitate the fabrication of magnetoinductive lenses for nuclear magnetic resonance. The presented analysis of the properties of periodic resonant structures is mainly based on numerical models utilising the finite element method, and this approach is combined with both the derivation of the corresponding analytical relations and an experimental measurement of the non-radiating component of the electromagnetic field. The thesis includes a physical description of the basic elements of periodic resonant structures. Physical properties of the elements were examined in detail via numerical analysis. In the course of the research, the data acquired through this analysis and the related experimental measurement enabled the author to propose a method for optimising the most widely used resonant structures. Moreover, several new versions of resonant elements, structures, and fabrication techniques were also designed. The results obtained from the numerical analyses carried out to examine the central physical properties of the fabricated structure samples were all verified via the designed method for measuring the non-radiating component of the magnetic field.
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