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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 20 of 86 for “"Error estimation"”.
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Application of Improved Truncation Error Estimation Techniques to Adjoint Based Error Estimation and Grid Adaptation
… Dynamics (CFD) are subject to discretization error, which is locally generated by truncation error. The discretization error is extremely difficult to properly estimate and this in turn leads to uncertainty over the quality of the numerical solutions obtained via CFD methods and the …
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Adjoint Error Estimation for Elastohydrodynamic Lubrication
In this thesis, adjoint error estimation techniques are applied to complex elastohydrodynamic lubrication (EHL) problems. A functional is introduced, namely the friction, and justification is provided as to why this quantity, and hence its accuracy, is important. An iterative approach has been …
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Error estimation and adaptivity in deformable solid dynamics
In this dissertation we study the error due to the temporal discretization in numerical simulations of deformable solid dynamics . For that, we start from the semidiscrete equations of motion and analyze the conditions that an estimator must satisfy to compute accurate results. With them, two …
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Residual-Based Discretization Error Estimation for Unsteady Flows
… to have rigorous techniques to estimate the error produced when using CFD. This thesis develops techniques to estimate discretization error for unsteady flows using the unsteady error transport equation (ETE) as well as defect correction. A framework to obtain exact truncation error and …
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Adaptive error estimation in linearized ocean general circulation models
… The statistics of the model and measurement errors need to be specified a priori. In this study we address the problem of estimating model and measurement error statistics from observations. We start by testing the Myers and Tapley (1976, MT) method of adaptive error estimation with …
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Error estimation for single-image human body mesh reconstruction
Human pose and shape estimation methods continue to suffer in situations where one or more parts of the body are occluded. More importantly, these methods cannot express when their predicted pose is incorrect. This has serious consequences when these methods are used in human-robot interaction …
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Adaptive error estimation in linearized ocean general circulation models
… The statistics of the model and measurement errors need to be specified a priori. In this study we address the problem of estimating model and measurement error statistics from observations. We start by testing the Myers and Tapley (1976, MT) method of adaptive error estimation with …
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Residual-based Discretization Error Estimation for Computational Fluid Dynamics
… and most difficult numerical approximation error to estimate is discretization error. Residual-based discretization error estimation methods are a category of error estimators that use an estimate of the source of discretization error and information about the specific application to …
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Subject-Generated Verbalized Strategy and Error Estimation During Skill Acquisition
1 PDF file (81 leaves)
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Reduced basis approximation and error estimation of parametrized partial differential equations
The student, Peter Sentz, submitted this Dissertation for approval on 2022-07-11 at 14:00.
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A variational multiscale a-posteriori error estimation method for nearly incompressible elasticity
This work presents an error estimation framework for a mixed displacement-pressure finite element method for nearly incompressible elasticity that is based on variational multiscale concepts. The displacement field is decomposed into coarse scales captured by the finite element mesh and fine scales …
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Error estimation in whole bone microstrain measurement when using digital volume correlation
… uncertainty in strain was quantified as strain error (SE), measured by analyzing repeated micro-CT scans of an uncompressed bone. The Minimum SE quantified was 180-225 microstrains in accuracy (mean), with a 1100-2100 microstrain precision (standard deviation) in rats; 10-150 microstrains in …
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Reduced-basis approximation a posteriori error estimation for parabolic partial differential equations
… in parameter-time space; (ii) a posteriori error estimation - relaxations of the error-residual equation that provide rigorous and sharp bounds for the error in specific outputs of interest: the error estimates serve a priori to construct our samples and a posteriori to confirm fidelity; and …
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Discretization Error Estimation Using the Error Transport Equations for Computational Fluid Dynamics Simulations
… methods, and finite-element methods. Error introduced in the discretization process is called discretization error and defined as the difference between the exact solution to the discrete equations and the exact solution to the partial differential or integral equations. For most CFD …
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Calibration of and Attitude Error Estimation for a Spaceborne Scatterometer using Measurements Over Land
… calibration and the host spacecraft's attitude error. The attitude references reported by the attitude control system on-board ADEOS are deemed erroneous. Results of this expanded technique, applied under varying assumptions, are presented for consideration. A summary and suggestions for future …
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Discretization Error Estimation and Exact Solution Generation Using the 2D Method of Nearby Problems
… solutions the MNP can be extended for use as an error estimator. The nearby problem can be solved numerically on the same grid as the original problem. The nearby problem discretization error is calculated as the difference between its numerical solution and exact solution (curve fit). This is an …
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Reduced basis approximation and a posteriori error estimation for non-coercive elliptic problems : applications to acoustics
… in parameter-time space; (ii) a posteriori error estimation - relaxations of the error-residual equation that provide rigorous and sharp bounds for the error in specific outputs of interest; and (iii) offline-online computational procedures - in the offline stage the reduced basis …
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On Numerical Error Estimation for the Finite-Volume Method with an Application to Computational Fluid Dynamics
… each CFD result inherently contains numerical errors that can significantly degrade the accuracy of a simulation. Discretization error is typically the largest contributor to the overall numerical error in a given simulation. Discretization error can be very difficult to estimate since the …
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Operator-adapted finite element wavelets : theory and applications to a posteriori error estimation and adaptive computational modeling
… a simple and unified approach for a posteriori error estimation and adaptive mesh refinement in finite element analysis using multiresolution signal processing principles. Given a sequence of nested discretizations of a domain we begin by constructing approximation spaces at each level of …
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