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Design and Measurement of Parameters of Acoustic Diffusors
Burda, Jan ; Vrba, Kamil (referee) ; Schimmel, Jiří (advisor)
This work focuses on the issue of acoustic diffusers. The introductory chapter describes the necessary theory of the sound distribution through enclosed space. Acoustic fields are also described. A description of the different diffusion element types and theirs design methods follows. It focuses mainly on design, which uses pseudo-random mathematical sequences. The aim of the work is to produce several types of acoustic diffusors and to verify their diffusion properties by means of measurements. The work uses the AFMG Reflex to simulate the diffusion properties of the proposed elements. Further, the thesis contains a description of the diffusion properties measurement process by the boundary plane method and the process of evaluating the measured data using the Matlab program.
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Design and Realization of Acoustic Solution for Listening Room
Burda, Jan ; Balík, Miroslav (referee) ; Schimmel, Jiří (advisor)
This work is focused on the problem of room acoustics and its analysis options. It describes the basic criteria of acoustic quality space, commonly used materials and acoustic tiles. It also deals with modeling and acoustic analysis of space using EASE. The third part of thesis is a detailed description of the design of acoustic elements based on resonance principle. The last part deals with the measurement of the reverberation time.
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Dendrochronological dating of catastrophic slope movements
Tumajer, Jan ; Treml, Václav (advisor) ; Burda, Jan (referee)
Mass-movements are one example of natural processes that can pose a serious risk for human beings and their possessions. Dendrochronology, a method capable of their reconstruction, can provide parameters of former events, which can be used for planning protective measures. The possibilities for the application of dendrochronological methods have been tested by means of meta-analysis of electronic and printed scientific articles and a case study focused on former avalanche activity in Schustler's avalanche path (Labský důl, Krkonoše Mts.). The main conclusion of the first one is the clear spatial disproportion of the recent dendrogeomorphological research activities - e.g. the dating of avalanches is typical for mountains of Montana (USA); the Alpine region (mainly Switzerland), on the other hand, absolutely dominates in the research of debris-flows. In the case study, the analysis of material with well-chosen indicators led to high accuracy results comparable with the results of scientific articles focused on avalanches, and made the identification of 14 years (in the period 1953-2007) with potential avalanche acitvity possible. Although methods of dendrogeomorphology are usually neglected in the research of avalanches in the Czech republic, their great potential for future applications is shown....
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Dynamics and spatial extension of recent landslides at the foot of Krušné Hory Mts. Regional study: Jezeří
Burda, Jan
Dynamika a rozšíření recentních svahových pohybů na úpatí Krušných hor | Abstrackt 1 ABSTRACT Recent mass movements currently comprise one of the main morphogenetic processes in the extensive anthropogenic relief of the foreground of the Krušné Hory Mountains in the Czech Republic. These mass movements result in several types of deep- seated slope failures, depending on the type of movement, lithological, structural, and geotechnical conditions and the water saturation of the landslide material. This thesis presents broad set of various methods of geomorphology, geophysics, engineering geology, dendrogeomorphology and geodesy in an attempt to fully understand the problem of slope failures in the Jezeří area located at the boundary between the Krušné Hory Mountains and the Most Basin (Czech Republic). An interdisciplinary approach has enabled an in-depth review of both the dynamics and development of recent slope failures as well as morphology and structure of slope failures. There are two sectors - Southeast and Southwest - with different types of slope failures. In the Southwest sector, mass movements occur in thick colluvial mantle and weathered Tertiary claystones. The main factors influencing their development include rainfall culminations, groundwater flowing from the valley of Šramnický Brook and...
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Design Of Acoustic Diffusers To Increase Room
Diffusion
Burda, Jan
This work focuses on design of acoustic diffusers and simulation of their influence on the acoustic field. The basic types are described in terms of their construction and scattering properties. The work also uses the AFMG Reflex simulation program. This makes it possible to verify the design for simple diffusers.
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Design and Measurement of Parameters of Acoustic Diffusors
Burda, Jan ; Vrba, Kamil (referee) ; Schimmel, Jiří (advisor)
This work focuses on the issue of acoustic diffusers. The introductory chapter describes the necessary theory of the sound distribution through enclosed space. Acoustic fields are also described. A description of the different diffusion element types and theirs design methods follows. It focuses mainly on design, which uses pseudo-random mathematical sequences. The aim of the work is to produce several types of acoustic diffusors and to verify their diffusion properties by means of measurements. The work uses the AFMG Reflex to simulate the diffusion properties of the proposed elements. Further, the thesis contains a description of the diffusion properties measurement process by the boundary plane method and the process of evaluating the measured data using the Matlab program.
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The dynamic of recent slope movements in the area of Jezeří in Krušné hory Mts.
Burda, Jan ; Vilímek, Vít (advisor) ; Klimeš, Jan (referee)
Diplomová práce: Hodnocení dynamiky recentních svahových pohybů v lokalitě Jezeří A B S T R A C T The object of this study is geomrphological research in natural hazardous area around Jezeří castle in Krušné hory Mts. This paper studies dynamics of mass movement in geologically and geomorphologically problematic area, where mining glaciate high up into the southeast-facing slope of the Krušné hory Mts. This paper presents results of dendrogeomorfological research. Trees reflect geomorphic processes in variety ways. Mass movemets often causes inclination of the tree trunk, this curvature is caused by the presure of reaction wood. We report results of 89 cores from 35 severely tilted trees (Fagus sylvatica). For reasons of sample depth, the analysis was limited to the period 1900-2006. In this period was accounted growth disturbances - excentricity of annual rings and sudden growth changes. This study presents results of correlation between growth disturbances and precipitations. The mass movemnts dynamic (creeping of quaternary sediments) is affected by precipitations. Significantly low mass movements "rates" can be observed during the 1940s and 1990s. In contrast, high mass movements "rates" were identified during the 1900s and the end of 1950s and during the 1970s. 4
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Analysis of the zone of recent deglaciation, Cordillera Blanca, Peru
Juřicová, Anna ; Vilímek, Vít (advisor) ; Burda, Jan (referee)
The master thesis is focused on analysis of the zone of recent deglaciation in the Cordillera Blanca, Peru. Geomorphological mapping that had been realized based on interpretation of the satellite data and field reconnaissance was used for interpretation of main geomorphological features and processes of the selected glacial valleys. Glaciofluvial processes and mass movements are the main processes that affected the relief in the recent period. Major differences in landforms presence and distribution have been found between the studied valleys. The main differences are between valleys located on the western side and eastern side of the mountains. Number of different sediments of different types have been identified on the western side, whereas no evidence of such sediments was found on the eastern side. These differences are probably caused by differences in geology and climatic conditions. Finally, a general sediment flux model on the information gained from the geomorfologic analysis has been created and shows space distribution of geomorphological features and processes. The analyses of the satellite data show different visual characteristics of the rocks, which has been confirmed during field works using Schmidt Hammer method. The results suggest that the rocks that have been exposed for longer time due...
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