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Simulation of sound wave propagation in closed space
Černý, Filip ; Kurc, David (referee) ; Orlovský, Kristián (advisor)
This thesis is dealing with problem and solution of simulation in room acoustics. At the beginning is introduction with sound as waves and his behavior in closed space. Following part of text is dealing with computional methods in room acoustics, statistics methods , ray-based methods, wave-based methods. Following are focused FDTD wave method, which serves as the basis for creating simulation algorithm.Last part of this work is practical sample of MATLAB aplication enviroment for simulation of sound waves in closed room by explicit sub-methods of method FDTD. The last section contains an example and discussion of the results of simulations.
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Geometry of isolated horizons
Flandera, Aleš ; Scholtz, Martin (advisor)
While the formalism of isolated horizons is known for some time, only quite recently the near horizon solution of Einstein's equations has been found in the Bondi-like coordinates by Krishnan in 2012. In this framework, the space-time is regarded as the characteristic initial value problem with the initial data given on the horizon and another null hypersurface. It is not clear, however, what ini- tial data reproduce the simplest physically relevant black hole solution, namely that of Kerr-Newman which describes stationary, axisymmetric black hole with charge. Moreover, Krishnan's construction employs the non-twisting null geodesic congruence and the tetrad which is parallelly propagated along this congruence. While the existence of such tetrad can be easily established in general, its explicit form can be very difficult to find and, in fact it has not been provided for the Kerr-Newman metric. The goal of this thesis was to fill this gap and provide a full description of the Kerr-Newman metric in the framework of isolated horizons. In the theoretical part of the thesis we review the spinor and Newman-Penrose formalism, basic geometry of isolated horizons and then present our results. Thesis is complemented by several appendices.
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Geometry of isolated horizons
Flandera, Aleš ; Scholtz, Martin (advisor)
While the formalism of isolated horizons is known for some time, only quite recently the near horizon solution of Einstein's equations has been found in the Bondi-like coordinates by Krishnan in 2012. In this framework, the space-time is regarded as the characteristic initial value problem with the initial data given on the horizon and another null hypersurface. It is not clear, however, what ini- tial data reproduce the simplest physically relevant black hole solution, namely that of Kerr-Newman which describes stationary, axisymmetric black hole with charge. Moreover, Krishnan's construction employs the non-twisting null geodesic congruence and the tetrad which is parallelly propagated along this congruence. While the existence of such tetrad can be easily established in general, its explicit form can be very difficult to find and, in fact it has not been provided for the Kerr-Newman metric. The goal of this thesis was to fill this gap and provide a full description of the Kerr-Newman metric in the framework of isolated horizons. In the theoretical part of the thesis we review the spinor and Newman-Penrose formalism, basic geometry of isolated horizons and then present our results. Thesis is complemented by several appendices.
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Geometry of isolated horizons
Flandera, Aleš ; Scholtz, Martin (advisor) ; Acquaviva, Giovanni (referee)
While the formalism of isolated horizons is known for some time, only quite recently the near horizon solution of Einstein's equations has been found in the Bondi-like coordinates by Krishnan in 2012. In this framework, the space-time is regarded as the characteristic initial value problem with the initial data given on the horizon and another null hypersurface. It is not clear, however, what ini- tial data reproduce the simplest physically relevant black hole solution, namely that of Kerr-Newman which describes stationary, axisymmetric black hole with charge. Moreover, Krishnan's construction employs the non-twisting null geodesic congruence and the tetrad which is parallelly propagated along this congruence. While the existence of such tetrad can be easily established in general, its explicit form can be very difficult to find and, in fact it has not been provided for the Kerr-Newman metric. The goal of this thesis was to fill this gap and provide a full description of the Kerr-Newman metric in the framework of isolated horizons. In the theoretical part of the thesis we review the spinor and Newman-Penrose formalism, basic geometry of isolated horizons and then present our results. Thesis is complemented by several appendices.
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Simulation of sound wave propagation in closed space
Černý, Filip ; Kurc, David (referee) ; Orlovský, Kristián (advisor)
This thesis is dealing with problem and solution of simulation in room acoustics. At the beginning is introduction with sound as waves and his behavior in closed space. Following part of text is dealing with computional methods in room acoustics, statistics methods , ray-based methods, wave-based methods. Following are focused FDTD wave method, which serves as the basis for creating simulation algorithm.Last part of this work is practical sample of MATLAB aplication enviroment for simulation of sound waves in closed room by explicit sub-methods of method FDTD. The last section contains an example and discussion of the results of simulations.
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