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 22 for “"surface evolution"”.
-
Modelling surface evolution coupled with tectonics
This study presents the development of 1D and 2D Surface Evolution Codes (SECs) and their coupling to any lithospheric-scale (thermo-)mechanical code with a quadrilateral structured surface mesh. Both SECs involve diffusion as approach for hillslope processes and the stream power law to reflect …
-
Multi-scale models for wafer surface evolution in chemical mechanical planarization
… better local and global planarization of wafer surface. However, CMP process is sensitive to the pattern structure variation across a chip. The material removal rates are different for the regions with different pattern structure. Therefore, CMP obtains local planarization but generates global …
-
Structure, Stress and Surface Evolution in Silicon Due to Ion Bombardment
… a new multiscale computational method to study surface evolution is developed. In the new method, called crater function method, an average response of the silicon surface to a single argon impact is computed using molecular dynamics simulations at 500eV beam energies. These average responses …
-
Validating surface evolution modeling on high temperature selective emitters : an investigation of the thermal stability of nano-scale surface structures for thermophotovoltaic systems
… over tine. One of the main contributors to surface evolution is surface diffusion. This investigation tested surface diffusion based simulation modeling, comparing computational results with experimental findings for high temperature annealed silicon, a cost effective material for testing …
-
The effects of capillarity on photonic crystal selective emitters
… of processes, with one of the most notable being surface evolution by capillary forces. By comprehensively simulating the morphological and optical effects of this phenomenon, in the form of surface diffusion, vapor transport, and grain boundary grooving, this thesis seeks to understand its …
-
Modeling the dynamics and depositional patterns of sandy rivers
… by these data, I develop a nonlinear stochastic surface evolution model for the topography of sandy rivers which captures the essence of bedform evolution in space and time. I then use a simplified kinematic model for bedform evolution to simulate the production of stratigraphy from migrating …
-
Simulation of axisymmetric stepped surfaces with a facet
… a small miscut from the plane of symmetry has a surface which consists of a series of atomic height steps separated by terraces. If the surface of this crystal is not in equilibrium with the surrounding medium, then its evolution is strongly mediated by the presence of these steps, which act as …
-
Registration of Images with Varying Topology using Embedded Maps
… proposed algorithm, 3D images are embedded as 4D surfaces in a Riemannian space. The registration is therefore conducted as a surface evolution, which is modeled by a diffusion process. Our algorithm differs from existing methods in the sense that it takes an a-priori estimation of areas with …
-
In situ studies of surface reactions affecting Li-ion battery failure
… regions, loss of active electrode material, gas evolution, electrolyte decomposition, and chemical reactions with packaging and current collectors. Particular side reactions dominating capacity fade vary with electrode and electrolyte chemistry. Many of the general trends and associated design …
-
Quantitative Analysis of River Profiles and Fluvial Landscapes
… rate only influences large-scale landscape evolution when it is varied at periods & 10 Ma. Thirdly, I build the naturalistic landscape simulation into an inverse scheme. Synthetic landscapes generated by known forcing are inverted as a function of regional uplift. Temporally varying forcing …
-
Contact and coalescence of viscous drops
When two fluid drops come into contact, surface tension quickly pulls the drops together into a single larger drop. This coalescence process is an example of a singular flow resulting from a topological transition, in this case between the disjoint and connected drops. In this thesis, we consider …
-
On the Rumpling Instability in Thermal Barrier Systems
… or progressive roughening of the BC surface in the BC-superalloy systems upon high temperature exposure. A combined experimental and analytical approach is taken to study the rumpling phenomenon. Thermal cycling and isothermal experiments are carried out in air and in vacuum to …
-
Development of a Multiscale Atomistic Code to Investigate Self-Organized Pattern Formation Induced by Ion Irradiation
… dependence of erosion and smoothening by surface diffusion. Recently, the development of the crater function theory has overturned this erosion-based paradigm to a redistribution-based paradigm. The theory has proved that erosion is irrelevant and negligible in the pattern formation at low …
-
Electronic structure and energetics of Fe-based superconductors: Effects of chemical and magnetic disorder in (Ba-X)(Fe-Y)2As2
… (DFT). For $Tm$ doping, we detail the Fermi-surface evolution and nesting that dictate instabilities to the observed spin-density wave (SDW) state. For Am doping we track topological changes in the Fermi surface and connect these to transitions between SC phases. For K-doping, dissolution of …
-
Linking morphology and reactivity: growth and ligand-assisted dissolution of cobalt oxyhydroxide.
… Identifying and quantifying the reactive surface area of these materials is vital to understanding the reactions in which they participate. The most basic effect of reactive surface area is governing the reaction rate at the surface but, in some cases, it is necessary to have a far more …
-
Generalized finite element methods for three-dimensional crack growth simulations
… element meshes that must fit the discontinuity surfaces while keeping the aspect ratio of the elements within acceptable bounds. Fully automatic generation of meshes in complex 3-D geometries satisfying these requirements is a daunting task. Partition-of-unity methods, such as the Generalized …
-
Use of molecular dynamics simulations to study the impact of weak to strong non-covalent chemical interactions
… on two fundamental processes, namely, gas-surface interactions and electrospray propulsion, respectively. For the gas-surface interaction work, we proved that conventionally used gas surface interaction models were not adequate in reproducing the lobular scattering behavior obtained from …
-
Modeling transient multiphase flow and mold top surface behavior in steel continuous casting
… flow physics in the mold region and mold top surface behavior during continuous casting of steel slabs. Each model can be used independently or combined together as a comprehensive system to gain insights into the inter-related multiphase fluid dynamics in the caster mold during both …
-
Fabrication of metal-oxide thin-films and features on dissimilar materials via ion-assisted codeposition
… optical, and electronic properties of the surface. One challenge in the fabrication of these dissimilar materials is that the heat often used to create oxide nanostructures results in the thermal decomposition of the polymer. This requires creative approaches to successfully merge these …
-
Development of accelerator based spatially resolved ion beam analysis techniques for the study of plasma materials interactions in magnetic fusion devices
… measurement of the modification to plasma-facing surfaces. Accelerated ~MeV ion beams are used to induce nuclear reactions or scattering, and by spectroscopic analysis of the resulting high energy particles (s', p, n, a, etc.), the material composition can be determined. PFCs can be analyzed to …
Page 1 of 2