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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
151

Kompaktní formy bydlení / Compact Forms of Housing

Májek, Jan Unknown Date (has links)
"The compact forms of housing" is a term with which the Czech interior design yet do not often occur. This concept densely built low-rise residential files yet carries a strong potential not only in matters of mere living, but also offers one of the progressive alternative ways of living environment in general. Examined form of residential buildings is becoming increasingly important especially in specific situations where conventional housing is failing and instead generates other social problems. This thesis is primarily seeking the maximum extent available to document the issue of a compact housing, describe its basic form and point out the historical roots of this typology. The acquired knowledge was then subjected to an in-depth analysis, the output of which is to be the most comprehensive characterization researched the topic and its inclusion in the context of the standard forms of housing. The result is a set of research information, assumptions and typological bases that determine the primary urban, architectural, or social limits of the residential category. This work attempts to take into account the specified topic in the broader context of housing as a basic human need. As a result of findings would be its contribution to the culture scene in our home and create a theoretical material that would become an essential information base for creating compact residential files. The conclusions of this research can be further developed, tested and refined in the educational process at the faculties of architecture or in the practice. The results of research could stimulate interest in this type of housing and contribute to the enrichment of Czech housing scene of a synthetic form, which will form the connecting link between the typological family house and an apartment building. Low-rise housing complexes with a high population density can also create an effective counterbalance to the typical suburban development of part-time family home and offer method, respectively one of the alternative ways to be with this dilapidated urban housing estate deal.
152

Šumová spektroskopie detektorů záření na bázi CdTe / The Noise Spectroscopy of Radiation Detectors Based on the CdTe

Zajaček, Jiří January 2009 (has links)
The main object of this work is noise spectroscopy of CdTe radiation detectors (-rays and X–rays) and CdTe samples. The study of stochastic phenomenon and tracing redundant low-frequency noise in semiconductor materials require long-term measurements in time domain and evaluate suitable power spectral densities (PSD) with logarithmic divided frequency axes. We have used the means of time-frequency analysis derived from the discrete wavelet transform (DWT) and we have designed the effective algorithm for PSD estimation, which is comparable with an original analog method. CdTe single crystal with Au contacts we can imagine as a series connection of two Schottky diodes with a resistor between them. The bulk resistance at constant temperature and other constant parameters changes due to the carrier concentration changing only. The p-type CdTe sample shows metal behavior with every temperature changes. Semiconductor properties of the sample begin to dominate just after some period of time. This behavior is caused by the hole mobility changing. The voltage noise spectral density of 1/f noise depends on the quantity of free carriers in the sample. All the studied samples have very high value of low frequency noise, much higher than it should have been according to Hooge’s formula. The excess value of low frequency noise is caused by the low carrier concentration within the depleted region.
153

Sídliště Lesná v kontextu času / Block housing estate Lesna in context of time

Guzdek, Adam Unknown Date (has links)
Brno Lesna is ranked among the most highly regarded housing estates in Czechoslovakia ever since it was built in the 1960s. Mainly due to its ideal location at southern slopes around natural ravine and timeless urban design. This settlement at the time also constituted the most perfect realization of the current method of construction in our country. It was fully functional and completely finished even before first residents moved in. However, cultivated expression of housing architecture was recently severely affected by inappropriate revitalization. Change of ownership after the events of November 1989 also opened the way for development companies desiring to open spaces to build new apartment buildings. Original inhabitants, though, fight against it and seek for protection of whole settlement as heritage.
154

Hodnocení stavu konstrukčního dřeva s užitím technologie odporového vrtání / Evaluation of the condition of structural timber using resistance drilling technology

Dziadková, Aneta January 2022 (has links)
The aim of this master thesis is to summarize the overview about characteristics and properties of timber and about diagnostic methods used for timber structures prospecting. Experimental part is focused on comparison of drill resistance measurement using Rinntech RESISTOGRAPH for samples at different moisture levels. This paper also includes building survey of roof truss of Litomyšl‘s library and structural report of rafter.
155

Elektronický šum piezokeramických snímačů akustické emise / Electronic Noise of Piezoceramic Sensors of Acoustic Emission

Majzner, Jiří January 2008 (has links)
In our work the analysis of electrical and noise characteristics of piezoceramic acoustic emission sensors is accomplished. The objective of our work is to analyze and optimize the signal-to-noise ratio. The starting point is the explanation of the noise origin in the acoustic emission sensors. The voltage fluctuation is caused by the dipole vibrations due to their interaction with phonons. The frequencies of dipoles vibrations have statistical distribution and the total energy of these vibrations is proportional to the temperature. The statistical distribution of vibration frequencies leads to the origination of the 1/f type noise spectral density. The interaction between the phonons and electric dipoles is characterized by the imaginary part of susceptibility which is related to the transformation of electric energy to the mechanical energy of vibrations. This process is irreversible and this forms important theoretical question whether the Callen-Welton fluctuation dissipation theorem could be used for the description of fluctuation processes in the acoustic emission sensors. In our work the influence of the real and imaginary part of the susceptibility on the noise and electrical characteristics is solved, the dissipation of electrical energy characterized by the imaginary part of susceptibility is described and the connection between the imaginary part of susceptibility and the noise power spectral density is discussed. Due to the fact that these processes originate in the interaction between electrical dipoles and phonons, we give account of the temperature dependencies of equivalent series resistance and power spectral density of noise voltage, respectively. Piezoceramics stiffness contribute significantly to the resonance creation hence the pressure influence on the sensor noise characteristics was studied. The signal-to-noise ration improvement requires the piezoceramic sample diameter increase for its constant thickness. The ratio of the noise spectral density and sensitivity is independent on the sample thickness. The noise voltage is proportional to the square root of spectral density and frequency bandwidth that is why for the high signal-to-noise ratio it is necessary to minimize the signal amplifier frequency bandwidth. The noise voltage power spectral density increases with the temperature while the activation energy is 20 meV for the temperature 300 K, and 80 meV for the temperature 400 K, respectively. The power spectral density of planar oscillations decreases with increasing pressure and simultaneously the resonant frequency increases. The bandwidth of the normalized spectral density increases with the pressure for the planar oscillations while is invariable for the thickness oscillations. For the examination of the influence of the piezoceramic electrical polarization on the electrical and noise characteristics the experimental study of these dependencies was accomplished for samples without polarization, and samples polarized by electric field EP = 500V/mm and 1000V/mm, respectively. The samples without polarization show the noise of 1/f type only which corresponds to the Callen-Welton fluctuation dissipation theorem. The polarization leads to the generation of planar and thickness oscillations and the power spectral density of voltage fluctuation on the electrodes is proportional to the temperature, and inversely proportional to the imaginary part of permittivity, to the sample area S, and the frequency f.
156

Dům krátké cesty / 5-Minutes Neighbourhood

Gregorová, Stanislava January 2016 (has links)
The specified area is located in the city district Brno - Židenice, near the railway station. The theme of the thesis is the architectural study of selected part of the multifunctional intense urban structure, which was solved in the pre-diploma project. Draft uses the building site intensively, provides high plot ratio and density of population, a wide range of functions in a relatively small area is related to the elimination of transportation. By using topography the proposal creates a permeable areas, buildings with relations to the surroundings and with quality public spaces and attractive housing. Pick-up railway cancels barrier and makes a space with landscaping. Readability is achieved by linking the territory from east to west by straight streets and from north to south by passages. The development creates three centers, the commercial center of the north, center of culture in the heart of the area and the center of relaxation and sport in the south. Basic grid of development has a checkerboard plan, which reflects the grid of surrounding structure. The new development varies in its scale, from large scale buildings in the parterre decays into smaller scale. Function division is horrizontal. There are underground parking, a parterre with shops and services, a floor with offices and work study open to the courtyard and housing on the upper floors. Thus formed structure provides enough light in the courtyards and flats. The segmentation is supported by materials, bricks in the parterre contrast with the monotone plaster on the upper floors.
157

Výpočtové modelování radiálních hydrodynamických ložisek pro vodní stroje / Computational modeling of radial hydrodynamic bearings for water machines

Pokorný, Jan January 2018 (has links)
The aim of this thesis is to calculate the stiffness and damping coefficients for radial hydrodynamic bearings. Cylindrical and lemon hydrodynamic bearings are considered. The solution to this problem mainly depends on the hydrodynamic pressure in the bearing. The numerical solution of the Reynolds equation is used to calculate the pressure. The effect of variable viscosity and density of the lubricant due to temperature changes is considered. The static equilibrium position of the journal centre is also solved. The stiffness and damping coefficients are determined using small amplitude journal motions about the equilibrium position. Three methods for determining these coefficients are presented. The outcome of this thesis is an algorithm for the calculation of stiffness and damping coefficients for cylindrical and lemon bearings. Results for lemon bearings are presented and comparison with the commercial software DynRot BR is made. The benefit of this thesis is the creation of an algorithm for the calculation of journal centre equilibrium position, a new way of incorporating the temperature changes in the viscosity and the density of the lubricant, and the modification of a method for calculating stiffness and damping coefficients based on experimental analogy.
158

Analýza reologických vlastností rostlinných olejů a jejich složek / Analysis of the rheological properties of vegetable oils and their components

Divílek, Petr January 2014 (has links)
This Master’s thesis is dealing with theoretical analysis of vegetable, mineral oils and synthetic fluids, and with measuring of density and viscosity of selected samples of electric insulating fluids. The main part of the thesis is focused on vegetable oils and their elements called fatty acids. Those are more detail described in separate capitols. In those capitols is described their utilization in engineering practice with focus on energetics, where vegetable oils are used in larger scale. In experimental part of the work is measurement of density and dynamic viscosity. Viscosity was measured on two different machines, first the Hoppler viscometer and on vibrating viscometer. Results of these measurement are evaluated in tables and graphs.
159

Praktické ukázky zpracování signálů / Practical examples of signal processing

Hanzálek, Pavel January 2019 (has links)
The thesis focuses on the issue of signal processing. Using practical examples, it tries to show the use of individual signal processing operations from a practical point of view. For each of the selected signal processing operations, an application is created in MATLAB, including a graphical interface for easier operation. The division of the thesis is such that each chapter is first analyzed from a theoretical point of view, then it is shown using a practical demonstration of what the operation is used in practice. Individual applications are described here, mainly in terms of how they are handled and their possible results. The results of the practical part are presented in the attachment of the thesis.

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