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Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
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Showing 1 to 16 of 16 for “"continuation methods"”.
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The solution of variable-geometry truss problems using new homotopy continuation methods
… usually a Newton method or a variant. For such methods to yield a solution, a starting point sufficiently close to the actual solution must be supplied. For systems of the size of those encountered in VGT problems, this is a formidable task. On the other hand, recently developed methods in …
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On matrix-free pseudo-arclength continuation methods applied to a nonlocal partial differential equation in 1+1D with pseudo-spectral time-stepping
… conditions [5]. We apply pseudo-spectral methods to numerically integrate initial states of the populations given as small perturbations from a homogeneous steady state from which bifurcations and dynamics have been studied from a linear and weakly nonlinear analysis perspective [10, 11]. …
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A computer assisted approach to Hilbert's 16th problem
… fields. In Chapter 3, we introduce parameter continuation methods and applications to multiparameter vectors. In Chapter 4, we summarize recent studies of quadratic systems and address the most used methods, including the uniqueness theorems and classifications of Hopf bifurcations. In Chapter …
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Methods for Analysis of Nonlinear Thermoacoustic Systems
… of parameter space where limit cycles exist. Two methods of finding limit cycles in large thermoacoustic sytems are presented: matrix-free continuation methods and gradient methods. Continuation methods find limit cycles numerically in the time domain, with no additional assumptions other than …
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Improving shock-capturing robustness for higher-order finite element solvers
… Grid adaptation, along with shock-capturing methods such as artificial viscosity, can be used to resolve the shock by targeting the key flow features for grid refinement. This is a powerful tool, but cannot proceed without first converging on an initially coarse, unrefined mesh. These coarse …
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C++ software for computing and visualizing 2-D manifolds using Henderson's algorithm
… its algorithms are based on numerical continuation methods, rather than on subdivision techniques, which allows its practical application to the computation of two-dimensional manifolds in high-dimensional Euclidean spaces. The overall software provides a graphical user interface, …
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On the problem of parallelizing manifold covering algorithms
Continuation methods are numerical algorithms used to determine the solution space of systems of nonlinear equations with associated sets of parameters. Such methods have been very successful in computing solution manifolds of dimension one. For higher dimensional manifolds, different techniques …
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Optimal large angle spacecraft rotational maneuvers
… are considered. Three relaxation/analytic continuation methods are developed for iteratively solving the two-point-boundary value problem which results in the treatment of these problems. The solutions obtained are required to rigorously satisfy the necessary conditions derived from …
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Numerical Methods for the Wigner-Poisson Equations
This thesis applies modern numerical methods to solve the Wigner-Poisson equations for simulating quantum mechanical electron transport in nanoscale semiconductor devices, in particular, a resonant tunneling diode (RTD). The goal of this dissertation is to provide engineers with a simulation tool …
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Nonlinear Analysis and Control of Aeroelastic Systems
… its sensitivities are obtained using numerical continuation methods and harmonic balance methods. It is shown that the developed optimal controller eliminates any existing subcritical LCOs by converting them to supercritical LCOs.
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New Techniques for Polynomial System Solving
… basis techniques we focus on highly developed methods from several other areas like linear algebra, discrete optimization, numerical analysis and number theory. We study some techniques from combinatorial optimization to transform a polynomial system solving problem into a (sparse) linear …
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Automatic programming of arc welding robots
… of knowledge acquisition using statistical methods is proposed. It is shown that these procedures did little to capture the private knowledge of experts (heuristics), but helped in determining general dependencies, and trends. A need was established for building the knowledge-based system …
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A unified approach to structure and controller design optimizations
… utilizing sequential linear programming and continuation methods is proposed. The second part of this dissertation examines various ideas associated with both theory and practical issues arising in optimizing for eigenvalue sensitivity and stability robustness with respect to parameter …
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A high resolution gravity survey for the detection of Pleistocene aquifers underlying the Fort Berthold Indian Reservation, North Dakota
… gravity field necessitated the use of filtering methods. These methods included using published data, upward continuation, and wavelength filtering. The upward continuation and. wavelength filtering were performed using the computer program FFTFIL (Hildenbrand, 1983). Both the published data and …
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Nonsmooth Distillation Models Robust to Convergence Errors: Numerical Methods and Topological Aspects
… utilizing rigorous process optimization methods, which are both essential tasks in designing more energy-efficient and economically viable processes. In this thesis we address these challenges by developing nonsmooth (i.e., non-differentiable) distillation models and equation-solving …
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Modeling of three-dimensional viscoelastic flows with free surfaces using a finite element method
… number. The code is an extension of the parallel methods developed by Caola et al. from two- to three-dimensional flows, a restructured and improved version of the three-dimensional code of Phillips based on the subproblem formulation. The free surface motion used is an extension of the …