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Unconventional Signals Oscillators
Hruboš, Zdeněk ; Galajda, Pavol (oponent) ; Štork, Milan (oponent) ; Petržela, Jiří (vedoucí práce)
The doctoral thesis deals with electronically adjustable oscillators suitable for signal generation, study of the nonlinear properties associated with the active elements used and, considering these, its capability to convert harmonic signal into chaotic waveform. Individual platforms for evolution of the strange attractors are discussed in detail. In the doctoral thesis, modeling of the real physical and biological systems exhibiting chaotic behavior by using analog electronic building blocks and modern functional devices (OTA, MO-OTA, CCII±, DVCC±, etc.) with experimental verification of proposed structures is presented. One part of theses deals with possibilities in the area of analog–digital synthesis of the nonlinear dynamical systems, the study of changes in the mathematical models and corresponding solutions. At the end is presented detailed analysis of the impact and influences of active elements parasitics in terms of qualitative changes in the global dynamic behavior of the individual systems and possibility of chaos destruction via parasitic properties of the used active devices.
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Dynamic model of nonlinear oscillator with piezoelectric layer
Sosna, Petr ; Lošák, Petr (oponent) ; Hadaš, Zdeněk (vedoucí práce)
This diploma thesis aims to analyze the behavior of a nonlinear magnetopiezoelastic vibrating beam. First, a~single-degree-of-freedom model of a real-world nonlinear energy harvester is developed. Numerical simulations of magnetic interaction provide a~basis for the mentioned stiffness nonlinearity. Qualitative and quantitative analyses of how the frequency response of such a~ system is affected by load resistance, amplitude of harmonic base excitation, and magnet separation distance are performed. Magnet separation distance acts as the main parameter that affects the level of nonlinearity and type of behavior. Therefore a significant portion of the work is dedicated to bifurcation diagrams, where the behavior and performance of the harvester are analyzed as a~function of magnet separation distance. These bifurcation diagrams also lead to performance maps, that could form the basis for efficient real-time tuning of the energy harvester. Important phenomena that can influence the harvested energy, when the system is excited by non-harmonic force, are also present. These include force impulses or noise-induced basin hopping.
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Stabilizace chaosu: metody a aplikace
Hůlka, Tomáš ; Dvořák, Jiří (oponent) ; Matoušek, Radomil (vedoucí práce)
Tato práce se zabývá deterministickým chaosem a vybranými možnostmi jeho stabilizace. Práce stručně přibližuje problematiku deterministického chaosu a uvádí běžně používané nástroje analýzy dynamických systémů vykazujících chaotické chování. Dále je uveden výčet nejčastěji studovaných chaotických systémů, následovaný popisem metod stabilizace chaosu a optimalizace těchto metod. Praktická část práce se věnuje stabilizaci dvou modelových systémů a jednoho reálného systému pomocí popsaných metod.
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Dynamic model of nonlinear oscillator with piezoelectric layer
Sosna, Petr ; Lošák, Petr (oponent) ; Hadaš, Zdeněk (vedoucí práce)
This diploma thesis aims to analyze the behavior of a nonlinear magnetopiezoelastic vibrating beam. First, a~single-degree-of-freedom model of a real-world nonlinear energy harvester is developed. Numerical simulations of magnetic interaction provide a~basis for the mentioned stiffness nonlinearity. Qualitative and quantitative analyses of how the frequency response of such a~ system is affected by load resistance, amplitude of harmonic base excitation, and magnet separation distance are performed. Magnet separation distance acts as the main parameter that affects the level of nonlinearity and type of behavior. Therefore a significant portion of the work is dedicated to bifurcation diagrams, where the behavior and performance of the harvester are analyzed as a~function of magnet separation distance. These bifurcation diagrams also lead to performance maps, that could form the basis for efficient real-time tuning of the energy harvester. Important phenomena that can influence the harvested energy, when the system is excited by non-harmonic force, are also present. These include force impulses or noise-induced basin hopping.
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Stabilizace chaosu: metody a aplikace
Hůlka, Tomáš ; Dvořák, Jiří (oponent) ; Matoušek, Radomil (vedoucí práce)
Tato práce se zabývá deterministickým chaosem a vybranými možnostmi jeho stabilizace. Práce stručně přibližuje problematiku deterministického chaosu a uvádí běžně používané nástroje analýzy dynamických systémů vykazujících chaotické chování. Dále je uveden výčet nejčastěji studovaných chaotických systémů, následovaný popisem metod stabilizace chaosu a optimalizace těchto metod. Praktická část práce se věnuje stabilizaci dvou modelových systémů a jednoho reálného systému pomocí popsaných metod.
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Unconventional Signals Oscillators
Hruboš, Zdeněk ; Galajda, Pavol (oponent) ; Štork, Milan (oponent) ; Petržela, Jiří (vedoucí práce)
The doctoral thesis deals with electronically adjustable oscillators suitable for signal generation, study of the nonlinear properties associated with the active elements used and, considering these, its capability to convert harmonic signal into chaotic waveform. Individual platforms for evolution of the strange attractors are discussed in detail. In the doctoral thesis, modeling of the real physical and biological systems exhibiting chaotic behavior by using analog electronic building blocks and modern functional devices (OTA, MO-OTA, CCII±, DVCC±, etc.) with experimental verification of proposed structures is presented. One part of theses deals with possibilities in the area of analog–digital synthesis of the nonlinear dynamical systems, the study of changes in the mathematical models and corresponding solutions. At the end is presented detailed analysis of the impact and influences of active elements parasitics in terms of qualitative changes in the global dynamic behavior of the individual systems and possibility of chaos destruction via parasitic properties of the used active devices.
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