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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.
81

Uživatelské měřicí moduly pro platformu cRIO / User-defined Measurement Modules for cRIO

Pivnička, Martin January 2015 (has links)
This thesis describes design and manufacture of measuring and communication modules for CompactRIO platform. In the first section is described platform from National Instrument suitable for measurement and control technology. There is written more fact about CompactRIO. The second part is focused on description of the hardware requirements needed to construct the module, communication and working modes. The third part describes information about support programs. At the end of third part is describes practical application of input digital card. Next section consists of practical proposal modules (input / output analog module, GPS modulu) and achievements.
82

Příprava a vlastnosti románského cementu / Preparation and Properties of Roman Cement

Opravil, Tomáš January 2009 (has links)
The Ph.D. thesis deals with the preparation of highly hydraulic binders based on roman cement. Roman cement (natural cement) is recently not available on the market due to uneconomic production of such a specific binder. On the other hand there is a big lack of information on this hydraulic binder. These results in failure in meeting the basic principle of modern approaches to restoration of historical buildings or monuments made of such kind of materials, which is such, that the materials used for restoration should be compatible with original material. Recognition of the processes of roman cement preparation based on progressive methods of study can provide substantial information for more efficient raw material selection or even for nontraditional utilization, for example for artworks. This work hence is aimed at studying and selection of traditional natural as well as nontraditional raw materials such as clay. This work also studies the preparation of highly hydraulic binders based on roman cement and the kinetics of burning and hydration processes
83

Kompaktní moduly nad nesingulárními okruhy / Compact modules over nonsingular rings

Kálnai, Peter January 2020 (has links)
This doctoral thesis provides several new results in which we leverage the inner structure of non-singular rings, in particular of self-injective von Neumann regular rings. First, we describe categorical and set-theoretical conditions under which all products of compact objects remain compact, where the notion of compactness is relativized with respect to a fixed subclass of objects. A special instance when such closure property holds are the classic module categories over rings of our interest. Moreover, we show that a potential counterexample for Köthe's Conjecture might be in the form of a countable local subring of a suitable simple self-injective von Neumann regular ring. 1
84

Aproximace statických modulů hornin z dynamických modulů stanovených akustickou karotáží pomocí T-matrix modelu / Approximation of static moduli of rocks from dynamic moduli determined by sonic well logging using T-matrix model

Chalupa, František January 2019 (has links)
(EN) Thesis deals with an approximation of static moduli in wells from dynamic moduli determined by acoustic well logging using T-matrix model. Proposed approach makes possible to determine moduli values, which are close to values of static moduli, which would be determined by loading tests. This approach is based on an idea, that an intact rock with sufficiently high compressional strength sc and sufficiently high value of static Young's modulus Es, manifests more or less linear elastic behaviour. In such case, the values of static and dynamic moduli are identical. This fact has been experimentally verified for rocks with values of sc and Es in order of higher tens of MPa and GPa respectively. In case of a rock damage presence in such rock, it's behaviour becomes nonlinearly elastic. The amount of nonlinearity is proportional to increasing amount of rock damage. This results in the difference between values of static and dynamic moduli. T-matrix model is used to quantify this difference. This model is based on an anisotropic rock matrix with ellipsoidal inclusions. These inclusions can affect each other. The result of this model calculation is a group of values of elastic constants, which we call effective moduli. These effective moduli include the effect of porosity in the rock as well and they...
85

Elasticitetsmodulen i en kalkstabiliserad vägterrass : en fältstudie / The elastic modulus in a lime stabilized subgrade : a study of the spatial variability

Olofsson Augustsson, Erik January 2010 (has links)
<p>Stabilization of subgrade is an internationally common technique to improve the characteristics of a soft soil. Improving the stiffness and bearing capacity of the subgrade enables the pavement to be designed with reduced depths of subbase and basecourse aggregates. This makes the stabilization technique both economically and environmentally interesting. Both natural and stabilized soils have high inherent property variability that should be considered when the characteristic value is derived. By analyzing the spatial variability in stabilized and natural subgrades it is possible get the parameters needed for reliability–based modeling of soil properties. I order to do so, three statistical parameters need to be evaluated, i.e. the mean, the variance and the scale of fluctuation, which is the distance within which soil properties show relatively strong correlation.</p><p>The objective of this thesis is to study different devises for determining the elastic modulus of subgrade and to study the spatial variability of the elastic modulus. With knowledge of this it is possible to optimize the testing. The different devises used in the field investigations was the light weight deflectometer (LWD), surface seismic and static plate loading. The different devices were used because they take measurements at different load- and strain levels.</p><p>Another aim was to investigate correlations between moduli determined by the different devices. This thesis is a part of a research project at Skanska about subgrade stabilization. The field studies were performed in Tygelsjö, south of Malmö, and the soil type was claytill. Two test areas, each 7x15 m, were stabilized with 6 % respective 4 % hydrated lime and two test areas, each 4x15 m, were left unstabilized. Totally 133 test points were investigated with the LWD and surface seismic and 11 static plate load tests were performed.</p><p>With geostatistical analyses of the experimental results the scale of fluctuation with respect to the elastic modulus has been evaluated to approximately 1,3 m. That means only points within 1,3 m reveal relative strong correlation. In practice this means that subsidence due to less stiffness in the stabilized subgrade will not be extensive in the surface. Therefore it’s not economically rational to design the pavement with respect to small areas with low stiffness in the subgrade.</p><p>Comparison between the LWD and the static plate load test showed that ____ is on average 2 times greater than ___. No correlations with the surface seismic were found. One influencing factor on the LWD measurements was the drop height. ____ decreased with increasing drop height but only on the unstabilized subgrade.</p><p>This thesis also shows how the characteristic value of the elastic modulus could be evaluated with statistical methods where the evaluation will depend on the number of measurements, the variability of the measurements and the variance reduction factor which in turn depends on the scale of fluctuation and the size of the mechanical system. This type of evaluation could be used as basis for reliability based design and design according to the observational method according to Eurocode 7.</p> / QC 20100706
86

Sensitivity studies with a surface and channel runoff module coupled to a mesoscale atmospheric model

Mölders, Nicole, Rühaak, Wolfram 06 December 2016 (has links) (PDF)
A module to investigate ground water recharge was developed, and implemented into the mesoscale meteorological model GESIMA (Geesthacht’s simulation model of the atmosphere) as well as coupled to a soil-vegetation scheme. Important features of the ground water module are the determination of surface and channel runoff. A comparison of the results provided by GESIMA with and without consideration of surface and channel runoff shows a remarkable impact of surface runoff on the soil moisture fluxes. Substituting water meadows by willow-forests demonstrates their importance for soil moisture fluxes. / Ein Modul zur Untersuchung von Grundwasserneubildung wurde entwickelt, in das mesoskalige meteorologische Modell GESIMA (Geesthachter Simulationsmodell der Atmosphäre) integriert und an ein Boden-Vegetationsmodell gekoppelt. Wesentliche Bestandteile des Grundwassermoduls sind die Berechnung des Oberflächen- und Gerinneabflusses. Ein Vergleich der Ergebnisse von GESIMA, die mit und ohne Oberflächen- und Gerinneabfluss erstellt wurden, belegt einen deutlichen Einfluss des Oberflächenabflusses auf die berechneten Feuchteflüsse im Boden. Untersuchungen zum Einfluss von Auenwäldern auf die Grundwasserneubildung belegen deren Bedeutung für die Wasserflüsse im Boden.
87

Přetvárné parametry brněnského téglu z malých deformací v trojosém přístroji / Stiffness anisotropy of Brno Tegel determined by continuous loading in triaxial tests

Mohyla, Tomáš January 2014 (has links)
This Thesis deals with the determination of Young's modulus and Poisson's ratio from the measurement of small strains (10-3 - 10-5 ) in triaxial tests on the overconsolidated Miocene clay from Moravia (Brno Tegel). The tests were performed in a hydraulic triaxial chamber, fitted with submersible local LVDT sensors, which were fixed directly on the sample. The tests were carried out on undisturbed samples of standard height and diameter (76x38 mm). There were three types of tests - isotropic loading probe, axial loading probe and shear test to the failure. The measured data were analyzed and the results were discussed. The research part of the Thesis briefly describes previous works on stiffness of Brno Tegel and also some works on stiffness of similar material to Brno Tegel - London Clay.
88

Moduly s minimální množinou generátorů / Moduly s minimální množinou generátorů

Hrbek, Michal January 2013 (has links)
Title: Modules with a minimal generating set Author: Michal Hrbek Department: Department of Algebra Supervisor: Mgr. Pavel Růžička, Ph.D., Department of Algebra Abstract: By a minimal generating set of a module we mean a subset which generates the module but any of its proper subsets does not. If the module is not finitely generated, an existence of a minimal generating set is not guaranteed. We say that a module is weakly based if it has a minimal generating set. In the presented thesis, we provide a characterization of weakly based modules over Dedekind domains. As an application of this, we show that the class of weakly based modules is not closed under extensions and the complement of this class is not closed under finite direct sums. Also, we show an example of an abelian group which is weakly based if and only if CH holds. Then we treat rings such that all modules are weakly based. We prove that a Baer regular ring has this property if and only if it is semisimple, and we show that any ℵ0-noetherian commutative semiartinian ring has this property. Final part of the text concerns the problem of Nashier and Nichols - does any generating set of any module over a perfect ring contain a minimal generating set? Keywords: module, minimal generating set, weak basis 1
89

Návrh a realizace aircraft interface device / Design and realization of aircraft interface device

Jankech, Tomáš January 2015 (has links)
The aim of this master’s thesis is a design and a realization of an interface device for various aircraft buses. The work shows the issue of Aircraft Interface Device and describes the most used types of avionics buses. It deals with the theoretical design of the PCI/104–Express module and is using modularity for maximum configurability of the device. The work also brings the selection of appropriate components and their use in design. The last part describes a firmware architecture.
90

Analýza personální práce / Possible applications of the personal module in enterprise information system

Valeš, Jaromír January 2010 (has links)
The goal of this thesis is to become familiar with the personal module within the framework of enterprise information system DIALOG 3000S and subsequent suggestion of measure and procedure when implementing its functions in operation. First of all, it concerns the functions linked with the organizational structure and professions within integrated. Theoretical part is focused on general introduction of enterprise processes widely, then the issues of personal information system are analyzed, especially its integration to the enterprise information system as a whole. The practical part features introduction of the company Romotop, ltd. and information system DIALOG 3000S, firstly its integrated personal module. Then the actual situation of the module is analyzed and thus the reflections which function should be putted in operation and the way of the procedure.

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