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Modelling of damping devices in interaction with a structure
Kalina, Martin ; Lehký, David (referee) ; Frantík, Petr (advisor)
The aim of my master’s thesis was to create models of the damping device and observing their behavior in interaction with the structure. First was the construction separately modeled with Java application named FyDiK2D like a model with one degree of freedom. Model of construction takes form like a high, thin rod with full circular cross section. The lower part was restrained into the subsoil. The design was to verify the correct functionality of the model by comparing the analytical and numerical solutions. For capturing the precise behavior of the structure was converted to a multi-stage model. Then the pendulum damper was applied on this construction and found amplitude lies in highest point of multi-stage model. He was then replaced by tuned mass damper. By comparing these amplitudes from both dampers was found which kind of damper is efficient for multi-stage model.
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Stabilitní analýza ocelových konstrukcí s imperfekcemi
Kalina, Martin ; Krejsa, Martin (referee) ; Kala, Jiří (referee) ; Kala, Zdeněk (advisor)
The aim of this work is focused on soluti0on stability problem of planar bar structures. The calculation algorithms and methods used for analysis of behavior of these structures are described. The discrete computational model of steel of von Mises planar truss is presented. The structure deformation is evaluated by seeking the minimal potential energy. The effect of vertical displacement of top joint is determined by step-by-step method, and Newton iteration. Symmetric and asymmetric effects of initial shape of geometric imperfections of axes of struts are used in the model. The work is focused on another step in research of mapping of potential energy of elastic structures with aim at arch structures. For selected hinged arch loaded by displacement in the midpoint, the area of two concurrently existing postcritical statical equilibrium states is scanned using dynamical relaxation and applying of a set of designed mapping methods.
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Experimental measuring of model house lift
Kalina, Martin ; Feiler, Zdeněk (referee) ; Koláčný, Josef (advisor)
This work describes a model of a house elevator with an EC motor ( Electronically Commutated Motor) and a programme essential for controlling of the model and adjusting of the protective features for a safe operation. The work deals with experimental measurement based on the model, firstly while being at idle run, and then while being loaded. It is focused on the identification of influencing the EC motor input by usage of the counterweight. The aim of the work is to process the measured data, which are then used for mechanical adaptation of the model and the consequent confrontation between the measured data gained before and after the adaptation. Also an important part of the work is the simulation of the elevator using the 3D SolidWorks Programme.
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Floor systems based on secondary raw materials from power industry
Kalina, Martin ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the possibility of using secondary raw materials from the energy industry especially the solid residues of high temperature combustion of coal. These materials should be now seen as a material with wide usage especially in the construction industry. One possibility of their usage is a replacement of binding parts in floor systems. The aim is to find the optimal composition of the mixture, which fits all the technical requirements and at the same time reduces the cost of its production. An advanced methods of powder X-ray diffraction analysis, particle size laser diffraction analysis and X-ray fluorescence analysis were used to determine the raw materials. Based on these analysis the experiments were designed focusing on the mechanical properties, the observation of the evolution of hydration’s heat in prepared mixtures and their time of setting and hardening.
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The composites materials based on the solid residues of fluidized combustion
Kalina, Martin ; Koplík, Jan (referee) ; Opravil, Tomáš (advisor)
This bachelor thesis deals with a study of possible preparation of composite materials based on the solid residues of fluidized bed combustion. It focuses mainly on the strength properties of prepared materials and the phase composition of incurred hydration products. A powder X-ray diffraction analysis was used to determine the phase composition of prepared stiffened samples. Based on analysis of raw materials (fluid ash), various ingredients and additives were added to the mixtures in order to modify the composition or rheological properties of the fresh mixtures. After 28 days of maturation, the phase composition of prepared samples and the development of compressive and tensile strength in bending were monitored.
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Abolition of Super-Gross Wage in the Czech Republic through the lens of the Multiple Streams Framework
Kalina, Martin ; Ochrana, František (advisor) ; Kohoutek, Jan (referee)
In general, the changes in the area of taxation do not represent anything exceptional. But sometimes a change comes along that leaves a more significant mark on people's minds as the super-gross wage did. It came into being in 2008, as part of the reform of public finance of that time. Despite numerous attempts and efforts to cancel it, it lasted for 13 years. It was finally cancelled at the end of 2020 amid the COVID-19 epidemic. The final thesis, therefore, focuses on its definitive abolition. The aim of the diploma thesis is to examine the abolition of super-gross wage from the point of view of public policy and to understand the process of the abolition of super-gross wage in the Czech Republic with regard to both the policy stage of agenda setting and the policy stage of decision making. The thesis looks at the research problem through the lens of the multiple streams framework. It is conceived as a qualitative case study, where the data represent media outputs that are analysed using thematic analysis.
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Qatar and the Afghan Peace Talks
Kalina, Martin ; Koláček, Jakub (advisor) ; Ťupek, Pavel (referee)
The aim of the work is to introduce the peace negotiations between the United States of America and Taliban in the Qatari capital Doha during the second decade of the modern conflict in Afghanistan. In addition to describing the negotiations that took place, it approximates the nature of US efforts and interest in resolving the long-term war and also explains the complexity of the conflict in the context of other involved regional powers. Special attention is paid to Qatar as the host country for the peace negotiations which with the support of its own mineral resources and media power has taken via its current foreign policy important position in regional development.
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Experimental measuring of model house lift
Kalina, Martin ; Feiler, Zdeněk (referee) ; Koláčný, Josef (advisor)
This work describes a model of a house elevator with an EC motor ( Electronically Commutated Motor) and a programme essential for controlling of the model and adjusting of the protective features for a safe operation. The work deals with experimental measurement based on the model, firstly while being at idle run, and then while being loaded. It is focused on the identification of influencing the EC motor input by usage of the counterweight. The aim of the work is to process the measured data, which are then used for mechanical adaptation of the model and the consequent confrontation between the measured data gained before and after the adaptation. Also an important part of the work is the simulation of the elevator using the 3D SolidWorks Programme.
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Modelling of damping devices in interaction with a structure
Kalina, Martin ; Lehký, David (referee) ; Frantík, Petr (advisor)
The aim of my master’s thesis was to create models of the damping device and observing their behavior in interaction with the structure. First was the construction separately modeled with Java application named FyDiK2D like a model with one degree of freedom. Model of construction takes form like a high, thin rod with full circular cross section. The lower part was restrained into the subsoil. The design was to verify the correct functionality of the model by comparing the analytical and numerical solutions. For capturing the precise behavior of the structure was converted to a multi-stage model. Then the pendulum damper was applied on this construction and found amplitude lies in highest point of multi-stage model. He was then replaced by tuned mass damper. By comparing these amplitudes from both dampers was found which kind of damper is efficient for multi-stage model.
|
|
|
Floor systems based on secondary raw materials from power industry
Kalina, Martin ; Švec, Jiří (referee) ; Opravil, Tomáš (advisor)
This thesis deals with the possibility of using secondary raw materials from the energy industry especially the solid residues of high temperature combustion of coal. These materials should be now seen as a material with wide usage especially in the construction industry. One possibility of their usage is a replacement of binding parts in floor systems. The aim is to find the optimal composition of the mixture, which fits all the technical requirements and at the same time reduces the cost of its production. An advanced methods of powder X-ray diffraction analysis, particle size laser diffraction analysis and X-ray fluorescence analysis were used to determine the raw materials. Based on these analysis the experiments were designed focusing on the mechanical properties, the observation of the evolution of hydration’s heat in prepared mixtures and their time of setting and hardening.
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