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Numerical methods for vortex dynamics
Outrata, Ondřej ; Hron, Jaroslav (advisor) ; Šístek, Jakub (referee)
Two aspects of solving the incompressible Navier-Stokes equations are described in the thesis. The preconditioning of the algebraic systems arising from the Finite Element Method discretization of the Navier-Stokes equations is complex due to the saddle point structure of the resulting algebraic problems. The Pressure Convection Diffusion Reaction and the Least Squares Commutator preconditioners constitute two possible choices studied in the thesis. Solving the flow problems in time-dependent domains requires special numerical methods, such as the Fictitious Boundary method and the Arbitrary Lagrangian Eulerian formulation of Navier-Stokes equations which are used in the thesis. The problems examined in the thesis are simulations of experiments conducted in liquid Helium at low temperatures. These simulations can be used to establish a relationship between vorticity and new quantity pseudovorticity in an experiment-like setting.
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Projection method applied to modelling blood flow in cerebral aneurysm
Hrnčíř, Jakub ; Hron, Jaroslav (advisor) ; Knobloch, Petr (referee)
This thesis is motivated by a problem of cerebral aneurysms, which are abnormal bulges on the arteries which supply blood for our brain. These aneurysms can rupture and cause death or permanent neurological deficits. To study the evolution of aneurysms and assess the risk of rupture, mathematical modelling might be used to compute otherwise unobtainable information about blood flow inside the aneurysm. For this reason it is essential to be able to model blood flow in sufficiently high resolution. A goal of this thesis was to implement standard projection method for the solution of unsteady incompressible Navier-Stokes equations using the free finite element software FEniCS to create a working code adjusted to the need of this particular application. The incremental pressure correction scheme was chosen. Various shortcomings of this method are described and a proper choice of boundary conditions and other implementation issues are discussed. A comparison of computed important hemodynamic indicator wall shear stress using new and previously used solution approach are compared. A test of the new code for parallel efficiency and performance on finer meshes for a real medical case was conducted. Powered by TCPDF (www.tcpdf.org)
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Numerical methods for vortex dynamics
Outrata, Ondřej ; Hron, Jaroslav (advisor) ; Šístek, Jakub (referee)
Two aspects of solving the incompressible Navier-Stokes equations are described in the thesis. The preconditioning of the algebraic systems arising from the Finite Element Method discretization of the Navier-Stokes equations is complex due to the saddle point structure of the resulting algebraic problems. The Pressure Convection Diffusion Reaction and the Least Squares Commutator preconditioners constitute two possible choices studied in the thesis. Solving the flow problems in time-dependent domains requires special numerical methods, such as the Fictitious Boundary method and the Arbitrary Lagrangian Eulerian formulation of Navier-Stokes equations which are used in the thesis. The problems examined in the thesis are simulations of experiments conducted in liquid Helium at low temperatures. These simulations can be used to establish a relationship between vorticity and new quantity pseudovorticity in an experiment-like setting.
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Projection method applied to modelling blood flow in cerebral aneurysm
Hrnčíř, Jakub ; Hron, Jaroslav (advisor) ; Knobloch, Petr (referee)
This thesis is motivated by a problem of cerebral aneurysms, which are abnormal bulges on the arteries which supply blood for our brain. These aneurysms can rupture and cause death or permanent neurological deficits. To study the evolution of aneurysms and assess the risk of rupture, mathematical modelling might be used to compute otherwise unobtainable information about blood flow inside the aneurysm. For this reason it is essential to be able to model blood flow in sufficiently high resolution. A goal of this thesis was to implement standard projection method for the solution of unsteady incompressible Navier-Stokes equations using the free finite element software FEniCS to create a working code adjusted to the need of this particular application. The incremental pressure correction scheme was chosen. Various shortcomings of this method are described and a proper choice of boundary conditions and other implementation issues are discussed. A comparison of computed important hemodynamic indicator wall shear stress using new and previously used solution approach are compared. A test of the new code for parallel efficiency and performance on finer meshes for a real medical case was conducted. Powered by TCPDF (www.tcpdf.org)
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The emerging market of cosmetics for men: An investigation of consumer behavior in Czech republic
Orlichová, Zuzana ; Chytková, Zuzana (advisor) ; Stříteský, Václav (referee)
The aim of this study is to describe adoption barriers emerging on the cosmetics for men market through market research and consumer behaviour exploration. The relationship men have with the cosmetics is not easy to understand, so the purpose of this study is to explore on what is based their relationship to cosmetics market - why some are ready to use cosmetics while other reject. Regarding market of cosmetics for men, there are the barriers that prevent in adoption of cosmetics. The thesis would reveal what influence the social decision making, and would go deeper into what influence men; and what the relationships with products, brands, services, and environment they have. The conclusion will be the interpretation of the adoption barriers on cosmetics for men market.
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