This dissertation uses argon geochronology and cosmogenic nuclide surface exposure dating methods to address three research questions. The first question concerns a geomagnetic instability recorded in lava flows on the island of Floreana in the Galapagos Archipelago. Changes in the Earth’s magnetic field (intensity and orientation) occur frequently throughout geologic...
Branched covering spaces are a mathematical concept which originates from complex analysis and topology and has found applications in tensor field topology and geometry re-meshing. Given a manifold surface and an N-way rotational symmetry field, a branched covering space is a manifold surface that has an N-to-1 map to the...
This study computationally and experimentally examines the mechanisms of crack penetration, deflection and the transition between penetration and deflection. The finite element analysis based computational modeling work used strength-and-energy based cohesive-zone approach to study the effect of dimensionless parameters (e.g., interfacial incident angle, fracture-length scale, and normalized toughness) on penetration/deflection...
In the current education environment, many instructors make use of some type of software, such as Visual Studio or a software library like OpenGL, in the classroom. Incorrect setup and configuration on an individual’s own system is a common problem when using these software tools. This thesis explores the difficulty...
Debugging, an integral part of software development, is difficult for end-user programmers, especially in the case of complex programs. The process of isolating errors is time consuming without the help of debugging support provided by the tool. For example, the visual programming tool LondonTube supports creation of custom mobile-cloud-web applications,...
Optimization of reservoir operation is involves various competing objectives for a scarce resource (water). To find the optimal operation of reservoirs, it is essential to consider multiple objectives simultaneously. There are various sources of uncertainty associated with the reservoir operation problem that should be considered as well.
The overarching goal...
Modeling tire-snow interaction is important in designing effective snow tires, which directly affects road safety during wintry weather. Unfortunately, tires have complex tread designs and the physical properties of snow have not been characterized. We employ the Material Point Method (MPM) for simulating a material that mimics the fracturing and...
Large numbers of reinforced concrete (RC) bridges were built in the past that are now considered seismically deficient. The structural members most likely to be considered deficient are the supporting columns. Typical deficient columns contain inadequate transverse reinforcement and poorly detailed lap splice lengths above the foundation. Insufficient lap splice...
While individual portfolio diversity analysis is a well-studied problem in visualization, the visual analysis of individual or groups of portfolios, over time, has received little attention. Such analysis, however, is important to researchers who are interested in better understanding portfolio management behavior of experts as well as novices. We conducted...