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 20 of 31 for “"forward modelling"”.
-
Forward modelling and inversion of streaming potential for the interpretation of hydraulic conditions from self-potential data
… embankment dam model are studied using the forward modelling algorithm and measured electrical properties to assess the sensitivity of the self-potential method in detecting internal erosion. Maximum self-potential anomalies are shown to be linked to large localized hydraulic gradients that …
-
The geochemistry of the Gough Island basalts and their mantle source region
… were calculated for use in constrained forward modelling. The primary magma compositions were calculated by the addition of 14-28% clinopyroxene and equilibrium olivine, in equal proportions, back into the primitive lava compositions in 1 % increments until an Mg# of 69 was reached. …
-
APPROXIMATE VS. PURELY NUMERICAL APPROACHES FOR FULL WAVEFORM MODELLING OF GLOBAL EARTH STRUCTURE
This thesis focuses on the global seismic forward modelling of body and surface waveforms in realistic 3-D Earth models using approximate and purely numerical methods. Firstly, we investigate two techniques: (i) the Born approximation, which should be valid for media with weak heterogeneity; and, …
-
On the Viscoelastic Deformation of the Earth
… way, it is first necessary to have a method of forward modelling the processes, that is, calculating the deformation due to a given forcing and in an earth model with a given structure. Given this, a way of calculating derivatives of measurements of the deformation with respect to the parameters …
-
Integrated numerical modelling of a polyhistory basin, Southern Cantabrian Basin (Palaeozoic, NW-Spain)
… prior to 2D reverse basin and 2D stratigraphic forward modelling. This study investigates the Southern Cantabrian Basin, which is the Variscan foreland fold-and-thrust belt of NW Spain. Structural balancing offers approximations of predeformational, spatial relationships between measured …
-
Controlling factors of two Middle Triassic carbonate platforms: Latemar and Rosengarten (Dolomites, Northern Italy)
… basin reverse and sequence stratigraphic forward modelling constrained burial and subsidence histories of the Rosengarten and Latemar platforms. Vitrinite reflectance and apatite fission track data both argue for a shallow maximum burial. Present day topography was overlain by a maximum …
-
Applicability of rock physics models in conjunction with seismic inverted data to characterize a low poro-perm gas-bearing sandstone reservoir for well location optimization, Bredasdorp Basin, SA
… main processes was implemented: (1) rock physics modelling, (2) a simultaneous seismic inversion, and (3) seismic reservoir characterization techniques. First, a rock physics model was generated as a bridge between the seismic observables (density, Vp and Vs) and reservoir parameters such as fluid …
-
Hydraulic properties of subglacial sediment determined from the mechanical response of water-filled boreholes
… solutions, if parameters are correctly chosen. Forward modelling of pressure records from three 1992 boreholes and three from other years indicates that the till underlying Trapridge Glacier has a hydraulic conductivity of 1.3 x 10⁻⁹-1.35 x 10⁻⁸ ms⁻¹, in agreement with previous indirect …
-
Coexistence of Slow Magnetoacoustic Waves and Thermal Limit Cycles in a Coronal Bright Point
… and density. Based on phase relations and forward modelling, we find that oscillations with periods up to around 5 and 10 min are likely associated with slow magnetoacoustic waves and thermal limit cycles, respectively. Time–distance maps along an oscillation region reveal …
-
Improving the Interpretation of Magnetic Tensor Data Using Deep Learning
… U-Net to predict kimberlite pipe locations by forward modelling magnetic susceptibility models to corresponding magnetic tensor data. I examined the use of different neural network architectures and methods for calculating loss to determine the effect on prediction accuracy. The U-Net was …
-
Global investigation of large earthquakes using InSAR and long-period seismic data
… data and by simplified assumptions used in the modelling. Large discrepancies for five earthquakes with magnitudes Mw 6.0 -Mw 8.1 are investigated in detail by comparing seismic data with theoretical seismograms calculated using two forward modelling techniques and 1-D and 3-D Earth models. For …
-
Time-resolved spectroscopic investigation of N2/H2 nanosecond pulsed discharges and EUV-induced low-temperature plasmas
… by instrumental-function characterisation and forward modelling of spectra. The (\mathrm{N_2}) Second Positive (SPS) and (\mathrm{N_2^+}) First Negative (FNS) band systems, together with the (\mathrm{H_2}) Fulcher-(\alpha) system, are used as sensitive probes of excitation pathways and as …
-
Deep learning for image processing in optical super-resolution microscopy
… data can be treated as the inverse problem of a forward modelling process. This relies on an approximative image formation model that takes uncertainties and noise into account. By training a deep neural network to invert the forward modelled SIM data, a highly generalised reconstruction model …
-
Geophysical Characterisation and Evolutionary Model of the Quaternary sediments in the North Offaly region of Central Ireland
… Radar (GPR) and Very Low Frequency (VLF). Forward modelling with GPRSIM and RES2DMOD software and geophysical ground truth evaluation in three test sites aided in the selection of the most efficient data collection, processing and interpretation methods, evaluation of the potential and …
-
Instrument Trade Studies for Satellite Remote Sensing of Ammonia
… is a challenge. Advances in radiative transfer modelling and radiometric instrument sensitivity have allowed for satellite NH3 observations to be performed by instruments such as NASA’s Tropospheric Emission Spectrometer and NASA’s Cross-track Infrared Sounder, but these instruments, and others …
-
Primordial evolution of cosmological perturbations: Theory and computation
… be the seeds of large-scale structure, therefore modelling their initial conditions and evolution is key to understanding how structure forms. Recent tensions in the inferred values of cosmological parameters have raised interest in models that deviate from the currently accepted standard model of …
-
Approaches to Multiscale Inverse Problems
… is an ill-posed inverse problem meaning that any modelling errors, such as neglecting the small scale, which are not accounted for can render estimate useless. A typical way of reducing the computational cost is to simply neglect any behaviour at the smaller scales, enabling a coarse …
-
Vertical Motions at the Fringes of the Icelandic Plume
… at each station. Both inverse- and guided forward modelling techniques are employed, as well as a Bayesian, trans-dimensional algorithm. Moho depths thus obtained are combined with seismic wide-angle and deep reflection data to produce a comprehensive crustal thickness map of northwestern …
-
A high resolution gravity survey for the detection of Pleistocene aquifers underlying the Fort Berthold Indian Reservation, North Dakota
… removed. </p><p> A three-dimensional computer modelling program was written to simulate the observed gravity anomalies. Forward modelling was then performed by adjusting density contrast, depth and thickness parameters. Shallow water well data were used to establish initial model parameters. …
-
Connecting models and observations of disc evolution and planet formation
… on planetary embryos, to planet migration. Forward modelling the available data, I showed that, although dust disc fluxes and sizes from ALMA snapshot surveys in nearby star-formation regions, and mass accretion rates from complementary VLT/X-Shooter spectroscopic surveys, cannot tell these …
Page 1 of 2