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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.
201

Implementing Service Model Visualizations : Utilizing Hyperbolic Tree Structures for Visualizing Service Models in Telecommunication Networks

Lundgren, Andreas January 2009 (has links)
<p>This paper describes the design, implementation and evaluation of HyperSALmon, a Java™ open source prototype for visualizing service models in telecommunication networks. For efficient browsing and graphical monitoring of service models using SALmon, a service modeling language and a monitoring engine (Leijon et al., 2008), some kind of interactive GUI that implements a visualization of the service model is desired. This is what HyperSALmon is intended to do. The prototype has been designed in accordance with suggestions derived from a current research report of visualization techniques (Sehlstedt, 2008) appropriate for displaying service model data. In addition to these suggestions domain experts at Data Ductus Nord AB has expressed an urge for implementation of further features, some of their suggestions are deduced from research documents (Leijon et al., 2008; Wallin and Leijon, 2007, 2006), while others have been stated orally in direct relation to the prototype implementation work. The main visualization proposal is to use tree structures. Thus, both traditional tree structures and hyperbolic tree structures have been utilized, where the main navigation is set to occur in the hyperbolic tree view. In order to contribute further to this report I provide a discussion addressing problems related to the context of implementing a prototype for service model visualization using open source frameworks that meets the requirements set by the service model network architecture, the domain experts and the suggestions in the research report (Sehlstedt, 2008,page 51-52). Finally, I will present drawn conclusions of the attempted prototype implementation, illustrating potential strengths and weaknesses and consequently introduce suggestions for possible improvement and further development.</p>
202

On Poicarés Uniformization Theorem

Bartolini, Gabriel January 2006 (has links)
<p>A compact Riemann surface can be realized as a quotient space $\mathcal{U}/\Gamma$, where $\mathcal{U}$ is the sphere $\Sigma$, the euclidian plane $\mathbb{C}$ or the hyperbolic plane $\mathcal{H}$ and $\Gamma$ is a discrete group of automorphisms. This induces a covering $p:\mathcal{U}\rightarrow\mathcal{U}/\Gamma$.</p><p>For each $\Gamma$ acting on $\mathcal{H}$ we have a polygon $P$ such that $\mathcal{H}$ is tesselated by $P$ under the actions of the elements of $\Gamma$. On the other hand if $P$ is a hyperbolic polygon with a side pairing satisfying certain conditions, then the group $\Gamma$ generated by the side pairing is discrete and $P$ tesselates $\mathcal{H}$ under $\Gamma$.</p>
203

Impedance and power transformations by the isometric circle method and non-Euclidean geometry

January 1957 (has links)
E. Folke Bolinder. / "June 14, 1957." / Bibliography: p. 91-96. / Army Signal Corps Contract DA36-039-sc-64637. Dept. of the Army Task 3-99-06-108 and Project 3-99-00-100.
204

Growth Series and Random Walks on Some Hyperbolic Graphs

Laurent@math.berkeley.edu 26 September 2001 (has links)
No description available.
205

Exponential function of pseudo-differential operators

Galstian, Anahit, Yagdjian, Karen January 1997 (has links)
The paper is devoted to the construction of the exponential function of a matrix pseudo-differential operator which do not satisfy any of the known theorems (see, Sec.8 Ch.VIII and Sec.2 Ch.XI of [17]). The applications to the construction of the fundamental solution for the Cauchy problem for the hyperbolic operators with the characteristics of variable multiplicity are given, too.
206

Global exact boundary controllability of a class of quasilinear hyperbolic systems of conservation laws II

De-Xing, Kong, Hui, Yao January 2003 (has links)
In this paper, by a new constructive method, the authors reprove the global exact boundary controllability of a class of quasilinear hyperbolic systems of conservation laws with linearly degenerate fields. It is shown that the system with nonlinear boundary conditions is globally exactly boundary controllable in the class of piecewise C¹ functions. In particular, the authors give the optimal control time of the system. Finally, a new application is also given.
207

On Poicarés Uniformization Theorem

Bartolini, Gabriel January 2006 (has links)
A compact Riemann surface can be realized as a quotient space $\mathcal/\Gamma$, where $\mathcal$ is the sphere $\Sigma$, the euclidian plane $\mathbb$ or the hyperbolic plane $\mathcal$ and $\Gamma$ is a discrete group of automorphisms. This induces a covering $p:\mathcal\rightarrow\mathcal/\Gamma$. For each $\Gamma$ acting on $\mathcal$ we have a polygon $P$ such that $\mathcal$ is tesselated by $P$ under the actions of the elements of $\Gamma$. On the other hand if $P$ is a hyperbolic polygon with a side pairing satisfying certain conditions, then the group $\Gamma$ generated by the side pairing is discrete and $P$ tesselates $\mathcal$ under $\Gamma$.
208

Classical and quantum fields on Lorentzian manifolds

Bär, Christian, Ginoux, Nicolas January 2012 (has links)
We construct bosonic and fermionic locally covariant quantum fields theories on curved backgrounds for large classes of fields. We investigate the quantum field and n-point functions induced by suitable states.
209

Numerical Modelling of van der Waals Fluids

Odeyemi, Tinuade A. 19 March 2012 (has links)
Many problems in fluid mechanics and material sciences deal with liquid-vapour flows. In these flows, the ideal gas assumption is not accurate and the van der Waals equation of state is usually used. This equation of state is non-convex and causes the solution domain to have two hyperbolic regions separated by an elliptic region. Therefore, the governing equations of these flows have a mixed elliptic-hyperbolic nature. Numerical oscillations usually appear with standard finite-difference space discretization schemes, and they persist when the order of accuracy of the semi-discrete scheme is increased. In this study, we propose to use a Chebyshev pseudospectral method for solving the governing equations. A comparison of the results of this method with very high-order (up to tenth-order accurate) finite difference schemes is presented, which shows that the proposed method leads to a lower level of numerical oscillations than other high-order finite difference schemes, and also does not exhibit fast-traveling packages of short waves which are usually observed in high-order finite difference methods. The proposed method can thus successfully capture various complex regimes of waves and phase transitions in both elliptic and hyperbolic regimes
210

Numerical Modelling of van der Waals Fluids

Odeyemi, Tinuade A. 19 March 2012 (has links)
Many problems in fluid mechanics and material sciences deal with liquid-vapour flows. In these flows, the ideal gas assumption is not accurate and the van der Waals equation of state is usually used. This equation of state is non-convex and causes the solution domain to have two hyperbolic regions separated by an elliptic region. Therefore, the governing equations of these flows have a mixed elliptic-hyperbolic nature. Numerical oscillations usually appear with standard finite-difference space discretization schemes, and they persist when the order of accuracy of the semi-discrete scheme is increased. In this study, we propose to use a Chebyshev pseudospectral method for solving the governing equations. A comparison of the results of this method with very high-order (up to tenth-order accurate) finite difference schemes is presented, which shows that the proposed method leads to a lower level of numerical oscillations than other high-order finite difference schemes, and also does not exhibit fast-traveling packages of short waves which are usually observed in high-order finite difference methods. The proposed method can thus successfully capture various complex regimes of waves and phase transitions in both elliptic and hyperbolic regimes

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