• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 215
  • 48
  • Tagged with
  • 263
  • 263
  • 259
  • 258
  • 107
  • 106
  • 92
  • 79
  • 79
  • 53
  • 50
  • 36
  • 36
  • 28
  • 27
  • 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.
1

New methods for movement technique development in cross-country skiing using mathematical models and simulation

Lund Ohlsson, Marie January 2009 (has links)
This Licentiate Thesis is devoted to the presentation and discussion of some new contributions in applied mathematics directed towards scientific computing in sports engineering. It considers inverse problems of biomechanical simulations with rigid body musculoskeletal systems especially in cross-country skiing. This is a contrast to the main research on cross-country skiing biomechanics, which is based mainly on experimental testing alone. The thesis consists of an introduction and five papers. The introduction motivates the context of the papers and puts them into a more general framework. Two papers (D and E) consider studies of real questions in cross-country skiing, which are modelled and simulated. The results give some interesting indications, concerning these challenging questions, which can be used as a basis for further research. However, the measurements are not accurate enough to give the final answers. Paper C is a simulation study which is more extensive than paper D and E, and is compared to electromyography measurements in the literature. Validation in biomechanical simulations is difficult and reducing mathematical errors is one way of reaching closer to more realistic results. Paper A examines well-posedness for forward dynamics with full muscle dynamics. Moreover, paper B is a technical report which describes the problem formulation and mathematical models and simulation from paper A in more detail. Our new modelling together with the simulations enable new possibilities. This is similar to simulations of applications in other engineering fields, and need in the same way be handled with care in order to achieve reliable results. The results in this thesis indicate that it can be very useful to use mathematical modelling and numerical simulations when describing cross-country skiing biomechanics. Hence, this thesis contributes to the possibility of beginning to use and develop such modelling and simulation techniques also in this context.
2

Using Beta as an Investment Strategy (A study of the Swedish Equity Market)

Ojeabulu, Godspower, Okoye, Chukwuemeka January 2010 (has links)
<p>This study investigates the effect of using the different benchmarks stated above to calculate the beta of some Swedish stocks and to form a high risk stock vis-a-vis a low risk stock. The stocks will be combined in different forms (scenarios) i.e. High beta stocks, low beta stocks and a mixture of both high and low beta stocks to form a portfolio of stocks and tested to see the performance level of the individual scenarios.<strong></strong></p>
3

New methods for movement technique development in cross-country skiing using mathematical models and simulation

Lund Ohlsson, Marie January 2009 (has links)
<p>This Licentiate Thesis is devoted to the presentation and discussion of some new contributions in applied mathematics directed towards scientific computing in sports engineering. It considers inverse problems of biomechanical simulations with rigid body musculoskeletal systems especially in cross-country skiing. This is a contrast to the main research on cross-country skiing biomechanics, which is based mainly on experimental testing alone. The thesis consists of an introduction and five papers. The introduction motivates the context of the papers and puts them into a more general framework. Two papers (D and E) consider studies of real questions in cross-country skiing, which are modelled and simulated. The results give some interesting indications, concerning these challenging questions, which can be used as a basis for further research. However, the measurements are not accurate enough to give the final answers. Paper C is a simulation study which is more extensive than paper D and E, and is compared to electromyography measurements in the literature. Validation in biomechanical simulations is difficult and reducing mathematical errors is one way of reaching closer to more realistic results. Paper A examines well-posedness for forward dynamics with full muscle dynamics. Moreover, paper B is a technical report which describes the problem formulation and mathematical models and simulation from paper A in more detail. Our new modelling together with the simulations enable new possibilities. This is similar to simulations of applications in other engineering fields, and need in the same way be handled with care in order to achieve reliable results. The results in this thesis indicate that it can be very useful to use mathematical modelling and numerical simulations when describing cross-country skiing biomechanics. Hence, this thesis contributes to the possibility of beginning to use and develop such modelling and simulation techniques also in this context.</p>
4

On the Branch Loci of Moduli Spaces of Riemann Surfaces of Low Genera

Bartolini, Gabriel January 2009 (has links)
<p>Compact Riemann surfaces of genus greater than 1 can be realized as quotient spaces of the hyperbolic plane by the action of Fuchsian groups. The Teichmüller space is the set of all complex structures of Riemann surfaces and the moduli space the set of conformal equivalence classes of Riemann surfaces. For genus greater than two the branch locus of the covering of the moduli space by the Teichmüller space can be identified wi the set of Riemann surfaces admitting non-trivial automorphisms. Here we give the orbifold structure of the branch locus of surfaces of genus 5 by studying the equisymmetric stratification of the branch locus. This gives the orbifold structure of the moduli space.</p><p>We also show that the strata corresponding to surfaces with automorphisms of order 2 and 3 belong to the same connected component for every genus. Further we show that the branch locus is connected with the exception of one isolated point for genera 5 and 6, it is connected for genus 7 and it is connected with the exception of two isolated points for genus 8.</p>
5

FEM-modelling of SSRT for Corrosion Tests

Lundquist, Tomas January 2010 (has links)
<p>This thesis discusses the mathematical formulation and computational treatment of slow strain rate corrosion tests based on nonlinear finite elements methods. The theory is illustrated by a description of classical small strain elastoplasticity theory as implemented in the Comsol Multiphysics 3.2 software package. The possible extension of the theory to finite strain is briefly addressed. Practical simulations and results regarding the evolution of stresses, strains and geometric deformation are also presented and discussed. Experimental data used in simulation where reported by Onchi, Takeo et al. and published in Journal of Nuclear Science and Technology in May 2006.</p>
6

FEM-modelling of SSRT for Corrosion Tests

Lundquist, Tomas January 2010 (has links)
This thesis discusses the mathematical formulation and computational treatment of slow strain rate corrosion tests based on nonlinear finite elements methods. The theory is illustrated by a description of classical small strain elastoplasticity theory as implemented in the Comsol Multiphysics 3.2 software package. The possible extension of the theory to finite strain is briefly addressed. Practical simulations and results regarding the evolution of stresses, strains and geometric deformation are also presented and discussed. Experimental data used in simulation where reported by Onchi, Takeo et al. and published in Journal of Nuclear Science and Technology in May 2006.
7

Convergence of Option Rewards

Lundgren, Robin January 2010 (has links)
This thesis consists of an introduction and five articles devoted to optimal stopping problems of American type options. In article A, we get general convergence results for the American option rewards for multivariate Markov price processes. These results are used to prove convergence of tree approximations presented in papers A, B, C and E.In article B, we study the problem of optimal reselling for European options. The problem can be transformed to the problem of exercising an American option with two underlying assets. An approximative binomial-trinomial tree algorithm for the reselling model is constructed. In article C, we continue our study of optimal reselling of European options and give the complete solution of the approximation problem. In the article D, we consider general knockout options of American type. A Monte-Carlo method is used to study structure of optimal stopping domains generated by combinations of different pay-off functions and knockout domains.In article E the American option with knock out domains is considered. In order to show convergence of the reward functional the problem is reformulated in such a way that the convergence results in paper A can be applied.
8

Movement of a prawn: a Hidden Markov Model approach

Alneberg, Johannes January 2011 (has links)
No description available.
9

Temperature effects on ant activity : Analysis of a mathematical model

Hallgren, Christoffer January 2012 (has links)
No description available.
10

Nonlinear phenomena and resource exploitation in group living organisms

Jamal, Muhammad January 2011 (has links)
No description available.

Page generated in 0.0993 seconds