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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.
221

Android aplikace pro doplňování zásob pojízdných kaváren / Android Application for Resupplying Coffee Bikes

Szakács, Tomáš January 2020 (has links)
My diploma thesis is focused on a comprehensive analysis of a selected company, its business environment and possible risks associated with the implementation of the proposed change in the supply process using a mobile application. My proposed solution includes a risk reduction method, a complex view of the processes in the application and its graphic design, along with the estimated costs of implementing the change.
222

Přístrojový transformátor napětí venkovního provedení. / Instrument voltage transformers of outdoor type

Velešík, Petr January 2008 (has links)
The function analysis of instrument voltage transformer with the aid of his equivalent diagram and his phasor diagrams is main part of my masters thesis. I solve the influence and errors of his equivalent diagram’s elements on this instrument voltage transformer. Than I talk about suitable magnetic materials using for instrument voltage transformers. There are 3D pictures which show lay-out of instrument voltage transformers’s windings and his magnetic circuit.
223

Optimalizace výrobního procesu / Optimization of production process

Nováková, Veronika January 2011 (has links)
The aims of this dissertation are to analyze the current state of process control, to identify the product range in selected organization and to design the process planning methodology to ensure an optimal implementation. Optimization is understood as costs minimization while keeping an acceptable continuity of supply. The dissertation contains a description of technological and non-manufacturing processes of brick products, as well as the summary and description of the basic tools of quality management.
224

Modulární informační systém pro publikování / Modular Information System for Publishing

Levinský, Stanislav January 2007 (has links)
This master thesis dives a brief introduction to the languages for creating web information systems and languages for creating web pages. It describes existing modular systems for publication (also known as content management systems, CSM), their advantages  and disavantages. Requirements for the Content Management System are specified and the  general scheme (ERD) for such a system is proposed. Presented system is realised in PHP and database system MySQL. Implemented user-friendly aplication running on the server communicates developed system that provides content management functions.
225

Analýza a návrh informačního systému řízení know-how v ICT společnosti / Analysis and Design of Know-How Management System in ICT Company

Pospíšil, Jiří January 2007 (has links)
The thesis deals with a problem of the design of information system. The design of system is provided with Rational Unifeid Process methodology. This thesis creates a list of requests to system. It makes an analysis and a design of current information system. It useses a RUP methodology to realize two first phases, inception phase and elaboration phase. Created elaboration phase of document is a base for creating programming prototype in Ruby on Rails environment using Ruby language with combination of HTML code.
226

Dispersion Characteristics of One-dimensional Photonic Band Gap Structures Composed of Metallic Inclusions

Khodami, Maryam 22 August 2012 (has links)
An innovative approach for characterization of one dimensional Photonic Band Gap structures comprised of metallic inclusions (i.e. subwavelength dipole elements or resonant ring elements) is presented. Through an efficient S- to T-parameters conversion technique, a detailed analysis has been performed to investigate the variation of the dispersion characteristics of 1-D PBG structures as a function of the cell element configuration. Also, for the first time, the angular sensitivity of the structure has been studied in order to obtain the projected band diagrams for both TE and TM polarizations. Polarization sensitivity of the subwavelength cell element is exploited to propose a novel combination of elements which allows achieving PBGs with simultaneous frequency and polarization selectivity. The proposed approach demonstrates that the dispersion characteristic of each orthogonal polarization can be independently adjusted with dipole elements parallel to that same polarization. Generally, the structure has potential applications in orthomode transducer, and generally whenever the polarization of the incoming signal is to be used as a means of separating it from another signal in the same frequency band that is of orthogonal polarization. The current distribution and the resonance behavior of the ring element is studied and the effect of resonance on dispersion characteristics of 1-D PBGs composed of rings is investigated for the first time, for both individual and coupled rings. Interestingly, it is observed that 1-D PBG composed of resonant elements consistently has a bandgap around the resonant frequency of the single layer structure.
227

Triangulações regulares e aplicações / Regular triangulations and applications

Pires, Fernando Bissi 27 June 2008 (has links)
A triangulação de Delaunay de um conjunto de pontos é uma importante entidade geométrica cujas aplicações abrangem diversas áreas da ciência. Triangulações regulares, que podem ser vistas como uma generalização da triangulação de Delaunay, onde pesos são associados aos vértices, também têm sido aplicadas em diversos problemas como reconstrução a partir de nuvens de pontos [5], geração de malha [12], modelagem molecular [7] e muitos outros. Apesar de ser muito utilizada, a fundamentação teórica referente à triangulação regular ainda não está tão desenvolvida quanto para triangulação de Delaunay. Por exemplo, pouco se sabe a respeito da dinâmica de uma triangulação regular [22] quando os pesos associados aos vértices mudam. Este trabalho tem como objetivo principal desenvolver um arcabouço teórico e computacional que permita representar uma triangulação qualquer como uma triangulação regular. Para isso, um estudo da dinâmica das operações de flip frente à variação de pesos nos vértices deve ser realizado. Este estudo tem como base o mapeamento da triangulação em um politopo que define os possíveis pesos para os vértices. Tal politopo pode ser obtido por meio de um sistema de inequações que gera um problema de programação linear cuja solução fornece os pesos adequados. A transformação de uma triangulação qualquer em triangulação regular permite o desenvolvimento de novas técnicas de morphing entre malhas e algoritmos para modelar níveis de detalhe, sendo este mais um objetivo deste trabalho / Delaunay triangulation of a set of points is an important geometrical entity whose applications encompass a range of scientfic fields. Regular triangulations, which can be seen as a generalization of Delaunay triangulation where weights are assigned to vertices, have also been widely employed in several problems, as for example mesh reconstruction from point clouds [5], mesh generation [12] and molecular modelling [7]. In spite of their applicability, the theoretical background of regular triangulations is not so developed as the theory of Delaunay triangulation. For example, the dynamic of regular triangulation is not completely known when the vertices weights change [22]. This work aims at developing a computational and theoretical framework that allow to represent a given triangulation as a regular triangulation. In this context, an investigation into the dynamic of edge ip operations regarding changes in the vertices weight must be accomplished. This investigation is based on mapping the triangulation in a polytope that defines the space of vertices weights. Such polytope can be built from an inequation system that can be associate to a linear program problem whose solution supplies the appropriated weights. By representing a triangulation as a regular triangulation one can conceive a new mesh morphing scheme and level of detail algorithm, being this another goal of this work
228

Application of Computational Thermodynamic and Solidification Kinetics to Cold Sprayable Powder Alloy Design

Belsito, Danielle L 14 January 2014 (has links)
Military aircraft that require high maneuverability, durability, ballistic protection, reparability, and energy efficiency require structural alloys with low density, high toughness, and high strength. Also, repairs to these aircraft demand a production process that has the flexibility to be relatively in-situ with the same high-performance output. Materials produced by the cold spray process, a thermo-mechanical powder consolidation technique, meet many of the requirements. In accordance with President Obama’s 2011 Materials Genome Initiative, the focus of this effort is to design customized aluminum alloy powders which exploit the unique behavior and properties of the materials created by the cold spray process. Analytical and computational models are used to customize microchemistry, thermal conditioning, and solidification behavior of the powders by predicting equilibrium and non-equilibrium microstructure and resulting materials properties and performance. Thermodynamic, kinetic, and solidification models are used, including commercial software packages Thermo-Calc, Pandat™, and JMatPro®, and TC-PRISMA. Predicted powder properties can be used as input into a cold spray process impact model to determine the consolidated materials’ properties. Mechanical properties of powder particles are predicted as a function of powder particle diameter and are compared to experimental results.
229

Effets de la deuxième orbitale dans les systèmes unidimensionnels de fermions alcalino-terreux ultrafroids / Study of cold fermionic alkaline earth atoms in one dimension

Bois, Valentin 28 March 2017 (has links)
La réalisation expérimentale de la condensation de Bose-Einstein (BEC) a ouvert un nouveau champ d'investigation très fertile dans l'étude des atomes froids. En particulier, la possibilité de synthétiser des gaz de fermions piégés dans des réseaux optiques représente un développement de la plus haute importance pour la physique de la matière condensée. Ceci ouvre notamment sur la perspective d'étudier des phases quantiques exotiques stabilisées dans des systèmes d'électrons fortement corrélés.Récemment, les gaz atomiques d'alcalino-terreux ou d'ytterbium ont suscité un vif intérêt et ont été refroidis jusqu'à la dégénérescence quantique. La structure atomique particulière de ces systèmes leur confère de très hauts degrés de symétrie, grâce au découplage entre le spin nucléaire et le moment angulaire électronique. Une physique exotique conduisant à de multiple applications peut résulter de ces systèmes de hautes symétries qui ne peut être sondée que par les solides bases de la matière condensée.Dans cette thèse, on se propose d'étudier les propriétés physiques de basse énergie d'un gaz de fermions de type alcalino-terreux, piégé dans un réseau optique à une dimension. À une dimension, il est possible d'analyser les effets des interactions de manière non-perturbative par des approches de théorie des champs comme la bosonisation ou la théorie des champs conformes, et numériquement par le groupe de renormalisation de la matrice densité (DMRG). L'ensemble de ces outils sera notamment utilisé pour déterminer le diagramme de phase des gaz de fermions d'alcalino-terreux ou d'ytterbium à une dimension. / Experimental realization of Bose-Einstein condensate (BEC) opened a new and rich field of investigation for the study of the cold atoms. In particular, the possibility of creating trapped fermionic gases in optical lattices represent one of the most important development for the condensed matter physics. This open the outlook of studying exotic and stabilized quantum phases in strongly correlated systems of electrons.Recently, alkline-earth or ytterbuim atomic gases have given rise to great interest and have been cooled down up to quantum degenaracy. The specific atomic structure of these systems confer them very high degrees of symetry, thanks to the decoupling beetwin the nuclear spin and the electronic angular momentum. An exotic physics which is only probe thanks to the strong fundament of the condensed matter.In this thesis, we propose to study the physical properties at low energy of a alkaline-earth-like fermionic gas, trapped in a one dimensional optical lattice. In one dimension, we are able to analyse effects of interactions in a non-pertubative way with conformal field theory or bosonization, and numerically with Density Matrix Renormalization Group (DMRG) approach. All of these tools will be used to provide the phase diagram of these alkaline-earth-like fermionic gases in one dimension.
230

Triangulações regulares e aplicações / Regular triangulations and applications

Fernando Bissi Pires 27 June 2008 (has links)
A triangulação de Delaunay de um conjunto de pontos é uma importante entidade geométrica cujas aplicações abrangem diversas áreas da ciência. Triangulações regulares, que podem ser vistas como uma generalização da triangulação de Delaunay, onde pesos são associados aos vértices, também têm sido aplicadas em diversos problemas como reconstrução a partir de nuvens de pontos [5], geração de malha [12], modelagem molecular [7] e muitos outros. Apesar de ser muito utilizada, a fundamentação teórica referente à triangulação regular ainda não está tão desenvolvida quanto para triangulação de Delaunay. Por exemplo, pouco se sabe a respeito da dinâmica de uma triangulação regular [22] quando os pesos associados aos vértices mudam. Este trabalho tem como objetivo principal desenvolver um arcabouço teórico e computacional que permita representar uma triangulação qualquer como uma triangulação regular. Para isso, um estudo da dinâmica das operações de flip frente à variação de pesos nos vértices deve ser realizado. Este estudo tem como base o mapeamento da triangulação em um politopo que define os possíveis pesos para os vértices. Tal politopo pode ser obtido por meio de um sistema de inequações que gera um problema de programação linear cuja solução fornece os pesos adequados. A transformação de uma triangulação qualquer em triangulação regular permite o desenvolvimento de novas técnicas de morphing entre malhas e algoritmos para modelar níveis de detalhe, sendo este mais um objetivo deste trabalho / Delaunay triangulation of a set of points is an important geometrical entity whose applications encompass a range of scientfic fields. Regular triangulations, which can be seen as a generalization of Delaunay triangulation where weights are assigned to vertices, have also been widely employed in several problems, as for example mesh reconstruction from point clouds [5], mesh generation [12] and molecular modelling [7]. In spite of their applicability, the theoretical background of regular triangulations is not so developed as the theory of Delaunay triangulation. For example, the dynamic of regular triangulation is not completely known when the vertices weights change [22]. This work aims at developing a computational and theoretical framework that allow to represent a given triangulation as a regular triangulation. In this context, an investigation into the dynamic of edge ip operations regarding changes in the vertices weight must be accomplished. This investigation is based on mapping the triangulation in a polytope that defines the space of vertices weights. Such polytope can be built from an inequation system that can be associate to a linear program problem whose solution supplies the appropriated weights. By representing a triangulation as a regular triangulation one can conceive a new mesh morphing scheme and level of detail algorithm, being this another goal of this work

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