Global ETD Search
Search theses and dissertations gathered from participating repositories worldwide. Every result links back to the library that holds it. No account is needed.
Results
Showing 1 to 13 of 13 for “"error growth"”.
-
Probabilistic state estimation in regimes of nonlinear error growth
… suitable for NWP are forced to assume that errors remain in regimes of linear error growth and retain distributions of Gaussian uncertainty, yet nonlinear systems like the atmosphere can readily allow regimes of nonlinear error growth and, in turn, produce distributions of non- Gaussian …
-
Improving numerical weather prediction: error growth at the convective scale and speed
Despite the continuous growth of the available computational power, it is undoubtedly beneficial, for both the research and operational communities, to increase the efficiency of Numerical Weather Prediction. Because parameterizations often occupy a significant portion of the total execution time …
-
The Effects of Ageing Error on Stock Assessment for Weakfish Cynoscion regalis
… of commercial and recreational fisheries. Error within ageing techniques, used to assess relative age frequencies within commercial and recreational harvest, has been cited as a potential source for uncertainty during assessments of the weakfish fishery. The implications for age-reading …
-
Canonical integration methods for Hamiltonian dynamical systems
… We show that for the two-body problem, the error growth in time for variable step size canonical methods is not in general quadratic. The error growth in time in the case of second-order integrators, canonical or non-canonical turns out to be approximately linear.
-
An investigation of thin film magnetic recording media
… media have been correlated to recording error and signal degradation measurements. Modified and adapted commercial Hi-8 video recorders have been used for sample generation whilst analytical techniques such as SXPS,IMS and SEM have been employed in the surface characterisation. The …
-
The Feasibility and Application of Observing Small LEO Satellites with Amateur Telescopes
… extended Kalman filtering, and temporal error growth in TLE-based orbit propagation. Further investigations include a preliminary optimization using MATLAB's fmincon function (informed by the previous analyses) to determine an optimal telescope size for performing LEO observations.</p>
-
Characterisation of local properties and prediction in chaotic dynamical systems
… predictability exist, as measured by FTLE. Growth of finite errors is calculated using ensembles. For small errors it is the same as that calculated with maximum-growth exponents. The worst-case error grows exponentially for small, according to a power law for large prediction times. The …
-
An Underwater Vehicle Navigation System Using Acoustic and Inertial Sensors
… of the INS is the “drift,” the unbounded error growth over time in the outputs. This thesis is aimed to study and test a combined UUV navigation system that fuses measurements from the INS, Doppler Velocity Log (DVL), and Short Baseline (SBL) acoustic positioning system to reduce the …
-
Mars entry navigation performance analysis using Monte Carlo techniques
… initial sensor activation altitude, and examines error sources and covariance trends for this entry and descent scenario. The results from the analysis show that large attitude uncertainty resulting from the LN200 IMU bias causes a breakdown of the filter algorithm dlue to nonlinearities. The …
-
Realising data-centric UAV autonomy through learning-based prediction and feedback integration
… transient and steady-tate behaviour and expose error structure. Under identical dataset splits and preprocessing, a companion LSTM baseline is trained for comparison; the NARX surrogate achieves higher accuracy on representative lateral and vertical manoeuvres and exhibits regular error growth …
-
Techniques to account for and reduce model inadequacy in ensemble-based filters
… for the accounting for parametric model error in the Ensemble Kalman Filter (EnKF) is investigated within the framework of Additive Error Approximation (AEA). The AEA needs an estimate of the model error covariance structure. The state-dependent model error structure is the sensitivity of …
-
Pole tip recession in linear tape systems
… Hence, PTR and subsequent which signal loss and error growth. The lower contact pressure of the LTO system comparing with the Travan5 system ensures that fewer and smaller three-body abrasive particles were swept across the poles and insulator regions. Hence, lower contact pressure, as well as …
-
An exact and consistent adjoint method for high-fidelity discretization of the compressible flow equations
… smaller scales will amplify any approximation errors made in the adjoint formulation. Formulating a practical exact adjoint that avoids such errors is especially challenging if it is to be compatible with state-of-the-art simulation methods used for the turbulent flow itself. Automatic …