Index Catalog // ScholarsArchive@OSU

Modeling Flow and Transport at Pore Scale with Obstructions

Creator:: Umhoefer, Joseph G.
Abstract:: In this thesis we study mathematical and computational models for phenomena of flow and transport in porous media in the presence of changing pore scale geometries. The differential equations for the flow and transport models at Darcy scale involve the coefficients of permeability, porosity, and tortuosity which depend on the...
Resource Type:: Dissertation

Exploring Student and Expert Understanding of Thermodynamic Potentials, Legendre Transformations, and Independent Variables in Thermodynamics

Creator:: Vignal, Michael
Abstract:: Thermodynamic potentials are energies that can describe a thermodynamic system in terms of different mathematically independent variables. Some of these potentials describe particular thermodynamic systems or processes in particularly convenient ways. In this dissertation, I discuss the different ways that students and experts reason about quantities in thermodynamics within the...
Resource Type:: Dissertation

Student Evaluative Sensemaking on Homework in Intermediate Mechanics

Creator:: Hahn, Kelby T.
Abstract:: Physicists seek to understand the world and often use mathematics to aid in attaining that goal. Thus when doing mathematics they often interrogate their results in order to ensure that they align with their expectations and to gain new insight into how the world works. This seeking of coherence between...
Resource Type:: Masters Thesis

Amorphous TiO₂ : A Thin Film Synthesis Route to Stabilization of Metastable TiO₂ Brookite

Creator:: Haggerty, James E. S.
Abstract:: Structure-specific synthesis processes are of key importance to the growth of polymorphic functional compounds such as TiO₂, where material properties strongly depend on structure as well as chemistry. The robust growth of the brookite polymorph of TiO₂, a promising photocatalyst, has been difficult in both powder and thin-film forms due...
Resource Type:: Dissertation and Video

Experimental Investigation of the Transition to Natural Convection in HTGR Applications using the Oregon State SFSETF

Creator:: Fishler, Joshua D.
Abstract:: High Temperature Gas Reactors (HTGRs) are positioned to disrupt local and global markets via their unique ability to produce carbon-free process heat, high efficiency power generation, and passively safe operational features. However, significant impediments still exist to delay deployment of this particular technology, including a lack of experimental data, verified...
Resource Type:: Dissertation

Radial Velocity Profiles and Magnetic Field Probes for Hypervelocity Plasma Deflagration Jets

Creator:: Rodriguez, Jesse A.
Abstract:: The fundamental physics of turbulence in plasma is not well understood. Recent studies of the plasma deflagration accelerator in the High Temperature Gasdynamics Lab at Stanford University have demonstrated the presence of small scale instabilities that limit the lifetime of the jet/Z pinch and are not reproduced by coaxial plasma...
Resource Type:: Honors College Thesis

Study of the Effects of Chain Whip Length and Bar Length on the Characteristics of Chain Shot

Creator:: Shannon, Eric R.
Abstract:: Timber harvesters are high powered industrial grade rigs used to fell, delimb, and cut to size large trees. Hydraulic motors power sprockets that drive chains around a guide bar that get extended through logs during cuts. As technological advances allow for higher speeds a phenomenon called “chain shot” has...
Resource Type:: Masters Thesis
Date Created:

Evaluating the Impact of Live Programming on Collaborative Software Development

Creator:: Ghorashi, Seyed Soroush
Abstract:: Collaboration is tricky, but often beneficial in the context of numerous software related activities, from learning core concepts, to the design and implementation of large software products. The growth of online classes, from small structured seminars to massive open online courses (MOOCs), and the isolation and impoverished learning experience some...
Resource Type:: Dissertation

Local Accessibility of Objective, Classical Reality

Creator:: Kincaid, Joshua J.
Abstract:: The fact that measuring a quantum system reduces it to apparently classical behavior, eliminating the interference patterns that are a hallmark of quantumness, cries out for an explanation. That explanation has been provided by the recognition of decoherence,whereby the interference is destroyed by the very interaction that acquires information.We begin...
Resource Type:: Dissertation

Radiative Acceleration and Emission from Relativistic Outflows

Creator:: Chhotray, Atul
Abstract:: Outflowing streams of matter or jets are a common phenomenon in the observeduniverse. The most extreme and powerful jets are relativistic, i.e., they travel at speedscomparable to the of speed light. Gamma Ray-Bursts (GRBs) and Active Galactic Nuclei(AGNs) are two sources of these relativistic jets. In this work I will...
Resource Type:: Dissertation

Radiation Shielding for Space Nuclear Propulsion

Creator:: Caffrey, Jarvis
Abstract:: Nuclear thermal propulsion (NTP) is a viable technology for near-term interplanetary exploration. Of the candidate mission architectures that are currently available for a crewed Mars mission, NTP permits the greatest flexibility in launch window selection and provides the shortest possible trip time, thereby reducing risks associated with cosmic ray exposure,...
Resource Type:: Dissertation

Don't Fool Me : Detecting Adversarial Examples in Deep Networks

Creator:: Li, Xin
Abstract:: Deep learning has greatly improved visual recognition in recent years. However, recent research has shown that there exist many adversarial examples that can negatively impact the performance of such an architecture. Different from previous perspectives that focus on improving the classifiers to detect the adversarial examples, this work focuses on...
Resource Type:: Masters Thesis

Terahertz Induced Non-linear Electron Dynamics in Nanoantenna Coated Semiconductors at the Sub-picosecond Timescale

Creator:: Stickel, Andrew
Abstract:: This dissertation is an exploration of the material response to Terahertz (THz) radiation. Specifically we will explore the ultrafast electron dynamics in the nonperturbative regime in semiconductors that have been patterned with nanoantenna arrays using broadband, high intensity, THz radiation. Three main semiconductor materials will be studied in this work....
Resource Type:: Dissertation

Nonlinear Terahertz Spectroscopy and imaging of Carbon Nanomaterials

Creator:: Lee, Byounghwak
Abstract:: This dissertation presents nonlinear terahertz (THz) properties of carbon nanomaterials investigated by time-resolved high-field THz spectroscopy. In order to determine THz characteristics of nanomaterials, we performed THz power spectrum measurement, THz raster imaging, THz time-domain spectroscopy (THz-TDS) and time-resolved pump-probe experiment on two different types of single layer graphene and...
Resource Type:: Dissertation

Community Colleges Creating Academic Programming for Rural Areas

Creator:: Garcia-Chitwood, Jean
Abstract:: Community colleges serve various populations as part of their missions. Many community colleges serve the people who live in rural communities and are challenged with fewer financial resources. The term rural is not easily defined, and many variables need to be considered when creating academic programming for rural populations. There...
Resource Type:: Dissertation

Evaluation of Parallel Monte Carlo Tree Search Algorithms in Python

Creator:: Jothi, Shankar
Abstract:: Monte-Carlo Tree Search (MCTS) is an online-planning algorithm for decision-theoretic planning in domains with stochastic and combinatorial structure. The general applicability of MCTS makes it an ideal first choice to investigate when developing planners for complex applications requiring automated control and planning. The first contribution of this thesis is to...
Resource Type:: Masters Thesis

Tensor Field Design and Analysis for Applications in Computer Graphics and Scientific Visualization

Creator:: Palacios, Jonathan
Abstract:: Many applications in computer graphics and geometry processing rely on the ability to locally orient 2D and 3D entities on a surface, or inside a volume, such as the sinusoidal kernels in Gabor noise, the color and geometry textures in pattern synthesis, and the finite elements in remeshing. In these...
Resource Type:: Dissertation

Nonlinear terahertz spectroscopy of carbon nanomaterials and semiconductor nanostructures

Creator:: Paul, Michael Jason
Abstract:: This thesis will cover my work relating to the developing field of terahertz (THz) science and technology. It will present experimental and theoretical studies investigating the optical and electrical properties of various material systems using novel THz imaging and spectroscopy techniques. Due to its low photon energy, THz imaging and...
Resource Type:: Dissertation

Liquid-gated carbon nanotube transistor noise sources and sensitivity limits

Creator:: Sharf, Tal
Abstract:: Low-dimensional electronic materials offer a platform to observe biological processes with unprecedented spatial and temporal resolution. Carbon nanotubes (CNTs) are the closest physical analog to an ideal 1D system and can be scaled and integrated into multiplexed electronic circuitry. The molecular structure of a CNT is also biocompatible, making them...
Resource Type:: Dissertation

Scanning photocurrent microscopy study of photovoltaic and thermoelectric effects in individual single-walled carbon nanotubes

Creator:: DeBorde, Tristan
Abstract:: Carbon Nanotubes are a unique family of nanostructures that have shown remarkable promise for mechanical, electrical, and optical applications. Fundamentally similar to the earlier discovered Buckminsterfullerene (C₆₀), carbon nanotubes are hollow cylinders formed from a single sheet of carbon atoms. The research presented in this dissertation investigates several carbon nanotube...
Resource Type:: Dissertation

Optical, electronic, and thermodynamic properties of layered mixed anion compounds

Creator:: Vielma, Jason Michael
Abstract:: Mixed anion compounds that form ZrCuSiAs-type crystal structures exhibit remarkable properties such as superconductivity at low temperatures, hole conduction with optical transparency in the visible region, and exciton absorption at room temperature. In this thesis, properties of a selected group of materials out of the very large set of mixed...
Resource Type:: Dissertation

Temporal gamma-ray spectrometry to quantify relative fissile material content

Creator:: Williford, Russell S.
Abstract:: A new method for delayed gamma-ray spectrometry to quantify the relative content of fissile material is developed and demonstrated to support international efforts in bolstering non-destructive assay capabilities. Previous traditional delayed gamma-ray spectrometry techniques rely upon nuclear data that often carry very high uncertainty. The new method removes the requirement...
Resource Type:: Dissertation

Extending the clinical applications of commercially available optically stimulated luminescence (OSL) dosimeters

Creator:: Keller, James R.
Abstract:: We present the results of our experiments designed to extend the clinical applications of commercially available Optically Stimulated Luminescence (OSL) Dosimeters. Our initial experiments demonstrate the linear response of the OSL dosimeters for doses under 200 cGy and the non-linear response of the device after 200 cGy. Our experiments show...
Resource Type:: Dissertation

A motor-generator and supercapacitor based system for microgrid frequency stabilization

Creator:: Crispo, Richard F.
Abstract:: This research introduces an energy storage system to deliver microgrid frequency response. A doubly-fed induction generator (DFIG) and a squirrel cage induction machine (SCIM) are coupled together as a motor/generator set to deliver an immediate inertial response to a change of frequency, and an inverter and supercapacitors deliver short term...
Resource Type:: Masters Thesis

Preliminary framework for the run-ahead predictive simulation software (RAPSS)

Creator:: Makinson, Kevin A.
Abstract:: The Run-Ahead Predictive Simulation Software (RAPSS) is an architecture designed for faster-than-real-time decision support for operators of complex networks. To enable further development of the RAPSS methodology, the necessary proof of principle is illustrated in two applications: decision support for shift technical advisors in nuclear power plant control rooms (RAPSS-STA),...
Resource Type:: Dissertation

Optoelectronic properties of organic semiconductor materials : from bulk to single molecule

Creator:: Shepherd, Whitney E. B.
Abstract:: The behavior and application of organic semiconductor materials depend strongly on their molecular structure, and molecular interactions. Several studies of intermolecular interactions in functionalized polyacene materials are presented. The degree and onset of aggregation of a functionalized anthradithiophene derivative was studied as a function of concentration in two different host...
Resource Type:: Dissertation

Design, construction, and characterization of a neutron depth profiling facility at the Oregon State University TRIGA® reactor with an advanced digital spectroscopy system

Creator:: Robinson, Joshua A.
Abstract:: In this work, Neutron Depth Profiling (NDP) analysis capability has been added to the Oregon State University TRIGA® Reactor Prompt Gamma Neutron Activation Analysis Facility (PGNAA). This system has been implemented with an advanced digital spectroscopy system and is capable of rise time pulse shape analysis as well as coincidence...
Resource Type:: Dissertation

Discrete-time quantum walks via interchange framework and memory in quantum evolution

Creator:: Dimcovic, Zlatko
Abstract:: One of the newer and rapidly developing approaches in quantum computing is based on "quantum walks," which are quantum processes on discrete space that evolve in either discrete or continuous time and are characterized by mixing of components at each step. The idea emerged in analogy with the classical random...
Resource Type:: Dissertation

An Ising-like model to predict dielectric properties of the relaxor ferroelectric solid solution BaTiO3 - Bi(Zn1/2Ti1/2)O3, An Ising-like model to predict dielectric properties of the relaxor ferroelectric solid solution BaTiO₃ − Bi(Zn₁/₂Ti₁/₂)O₃

Creator:: Jackson, Dennis L.
Abstract:: We developed a model to investigate the dielectric properties of the BaTiO₃ − Bi(Zn₁/₂Ti₁/₂)O₃ (BT-BZT) solid solution, which is a relaxor ferroelectric and exhibits long range disorder. The model uses ab initio methods to determine all polarization states for every atomic configuration of 2 x 2 x 2 supercells of...
Resource Type:: Dissertation

Submerged jet impingement boiling thermal management

Creator:: Cardenas, Ruander
Abstract:: Technologies such as avionics and power electronics are driving the demand for thermal management schemes towards high heat fluxes and low surface temperatures. Typically, these applications require the dissipation of heat fluxes in the rage of 100-1000 W/cm² while maintaining surface temperatures lower than about 85 °C. Phase-change heat transfer...
Resource Type:: Dissertation

Investigation of a hybrid quasi-diffusion/Monte Carlo method for solving multigroup criticality problems in slab geometry

Creator:: Robinson, Bethany R.
Abstract:: A hybrid Quasi-diffusion/Monte Carlo Method for solving multigroup criticality problems in slab geometry was investigated. Analog Monte Carlo was used to calculate functionals (Eddington Factors) that were then used in solution of the quasi-diffusion equations. The hybrid method was shown to accurately and precisely predict the k-eigenvalue and fission source...
Resource Type:: Masters Thesis

Computational nanooptics in hyperbolic metamaterials and plasmonic structures

Creator:: Thongrattanasiri, Sukosin
Abstract:: This dissertation concerns several problems in the fields of light interaction with nanostructured media, metamaterials, and plasmonics. We present a technique capable of extending operational bandwidth of hyperbolic metamaterials based on interleaved highly-doped InGaAs and undoped AlInAs multilayer stacks. The experimental results confirm theoretical predictions, exhibiting broadband negative refraction response...
Resource Type:: Dissertation

A study of actinide de-excitation through neutron emission from the deuteron induced fission of ²³⁸U

Creator:: Sprunger, Peter Hayden
Abstract:: The process of de-excitation of the actinides is a very important question in both pure and applied science. In this dissertation the process was studied using the neutrons emitted in coincidence with fission induced by the bombardment of ²³⁸U with 14.85 MeV deuterons. Neutrons can be emitted at multiple stages...
Resource Type:: Dissertation

A thin codimension-one decomposition of the Hilbert Cube

Creator:: Phon-On, Aniruth
Abstract:: For cell-like upper semicontinuous(usc) decompositions G of finite dimensional manifolds M, the decomposition space M/G turns out to be an ANR provided M/G is finite dimensional ([Dav07], page 129 ). Furthermore, if M/G is finite dimensional and has the Disjoint Disks Property (DDP), then M/G is homeomorphic to M ([Dav07],...
Resource Type:: Dissertation

An extension of the quantum theory of scattering to the non-asymptotic regime using Bohmian trajectories

Creator:: Stenson, Jared R.
Abstract:: Quantum mechanics provides a conventional theory of scattering that is limited in at least two ways: it focuses exclusively on the asymptotic regime and, in a more general sense characteristic of all quantum descriptions, provides no concrete account of individual particle evolution in spacetime. This is particularly true during the...
Resource Type:: Dissertation

Condensing observation of locale and agents : a state representation

Creator:: Valenti, Brett A
Abstract:: Computing agents require state information to make coherent and useful decisions. A state representation is a numerical translation of the environment and conditions that are pertinent factors in an agent's decision making. Although many representations, when paired with clever learning algorithms, are able to coordinate and capture prey in specific...
Resource Type:: Masters Thesis

Search Constraints

Search Results

Limit your search