Pillars in modern vehicles provide structural integrity by surrounding the windows and joining the roof with the frame. Although they protect the driver and passengers, A-pillars also create obstruction zones by limiting drivers' forward field of view leading to unforeseeable accidents or mishaps. We argue that providing a better pillar...
The neutron flux-energy spectral characterization of a Thermo Fisher MP320 deuterium-tritium neutron generator was performed for two shielding configurations, one with substantial moderator between the source and the sample and one without such moderator. The STAYSL PNNL spectral adjustment code was utilized in conjunction with MCNP modelled reference spectra and...
Natural uranium samples were irradiated in-core for 7 seconds using the pneumatic rabbit system within the TRIGA Mark II Reactor at Oregon State University, and then used to generate a gamma-ray spectrum with a high purity germanium (HPGe) detector. The irradiated sample was simulated in Monte Carlo N-Particle (MCNP), a...
The purpose of this work was to explore the feasibility of using the GOTHIC thermal hydraulics software package to model a pressurized conduction cooldown event in the High Temperature Test Facility. To achieve that aim, a model of the facility was constructed in the GOTHIC software and a selection of...
In this work, I developed a six degree of freedom flight simulator specific to liquid engine launch vehicles. This flight simulator improves upon available software by accounting for liquid engine specific phenomena such as tank pressurization, liquid engine performance, and center of gravity modeling. Additionally, I implemented methods for optimization...
Motion planning is a cornerstone of autonomous robots, enabling robots to safely and efficiently perform tasks such as package delivery, infrastructure inspection, and manipulation. However, as the field of robotics matures, robotic systems are being developed that (1) are challenging to analytically model, (2) require computationally expensive model-based controllers, and...
This dissertation presents novel, field-activated smart material systems for the actuation and control of autonomous robots. Smart materials, a type of material whose properties can be changed with an external stimuli, represent a promising direction to expand upon existing robotic control and actuation methods, particularly in the sub-fields of soft...
Radiological emergency plans ensure that protective actions can and will be taken in the event of an accident. Principle protective actions for the early phase of an emergency are evacuation and sheltering-in-place. While evacuations are generally safe, there are deterministic, long-term health consequences from prolonged displacement that outweigh the stochastic...
The Comprehensive Nuclear-Test-Ban Treaty (CTBT) prohibits the testing of nuclear weapons on the face of the earth. The detection of atmospheric radioxenon (131mXe, 133m/133Xe, and 135Xe) plays an important role in the identification of sub-surface clandestine nuclear weapon explosions. Since the radioxenon identified above decay via two radiation in coincidence,...
Faithful modeling of the expected gamma signals inside an electrochemical facility at various key measurement points is important for understanding what detection limits are available for the next generation of safeguards technologies. Gamma Detector Response and Analysis Software (GADRAS) and the Separation Safeguards Performance Model (SSPM) were used to build...
Ideally, dosimetric models for pine trees will accurately reflect the doses to its critical organs. However, existing models (e.g. that in ICRP 108) for the pine tree are over simplified or solely focused on estimating doses to one specific organ, and none of the existing models attempt dosimetry to the...
This is the investigation into The generation of high-fidelity multigroup multiband cross sections from Monte Carlo neutron transport simulations. Previous methods for generating multigroup multiband (MGMB) cross sections, and multigroup cross sections, assume an approximate shape for the scalar flux. This approximate flux shape is the product of an energy-dependent...
Though numerous drought metrics have been developed by the research community, adoption of these metrics by water managers has been limited. The reasons for this vary, but some include mismatches in time scales and spatial scales between the metric supplied and the operational decisions (e.g. water managers often work within...
During the past few decades, the U.S. Department of Energy (DOE) has made significant investments to improve nuclear data libraries, as the quality of this data impacts nearly all analyses of nuclear systems. Nuclear fission product yields are one component of these libraries, and are important for the analysis of...
This research seeks to identify how changes in temperature and oxygen concentration in the reaction zone affects liftoff heights for moderate or intense low-oxygen dilution (MILD) combustion of a jet fuel and a surrogate fuel. MILD combustion offers a method of burning fuels with reduced CO and NOx production by...
Instead of expensive and destructive chemical analysis, nondestructive assay (NDA) through radiography and tomography can be a faster, easier, and more appropriate method of analyzing spent nuclear fuel (SNF). As a preliminary study for the future design of a submersible SNF imaging system, this thesis demonstrates the ability of NDA...
Since the International Commission on Radiation Protection (ICRP) recommended a revision to the eye lens dose limits in ICRP Publication 118 (Stewart, 2012) the radiation protection community has conducted many new studies related to eye dosimetry. The recommended reduction of eye lens dose limits may result in the reduction of...
When the ICRP updated their recommended limits for eye dose, they ignited a renewed interest in eye dosimetry. Especially, how the updated eye dose estimates affect current regulations and what that would mean to a radiation worker. Radiation workers are commonly required to wear leaded eyeglasses to reduce their dose...
Medical Isotopes are a necessity in modern medicine for cancer treatments and medical imaging. In order to ensure that the needs and demands are met for the medical procedures, facilities are put in place to produce these isotopes. There are over 25 different isotopes of interest being produced by more...
Breast cancer is the leading cancer in women with an estimated 13% of women in the United States developing a form of invasive breast cancer in her lifetime. The survival rate is estimated to be 85%, but the American Cancer Society estimates that early detection of breast cancer in the...
Nanostructured material has been projected to be the next generation material for the detection of ionizing radiation due to the uniquely superior physical processes associated with charge creation and by virtue of their optoelectronic tunablility. Semiconducting Nanocrystal (NC) detectors, by nature of their low band gap material, low fabrication costs,...
Microtechnology was used to study the chemical reduction of dissolved carbon dioxide into useful products. A novel TiO₂ photocatalyst was used to activate the reaction under ultraviolet irradiation. CO₂ was dissolved in aqueous and 50% BMIM-BF₄ (ionic liquid) solutions. The introduction of an ionic liquid increased the solubility of CO₂...
As the negative impacts of a fossil fueled electricity market are becoming more prevalent and destructive, the necessity for alternative energy techniques increases as well. However, before commercial implementation is underway, these alternatives must be assessed from three important perspectives: environmentally, economically, and socially, which are known as the three...
This thesis describes calculations done to determine the radiation hazard of the current Prompt Gamma Neutron Activation Analysis (PGNAA) scattering chamber at the Oregon State TRIGA Reactor (OSTR) and compare it to the amount that would be given off by a new thin-walled chamber design. These calculations were completed with...
Detonation combustion is of great interest for propulsion devices because of its potential to increase thermodynamic efficiency, reduce the weight of current gas turbine engines, and rapidly accelerate to high Mach numbers. Detonation engines might also have the ability to decrease harmful exhaust products from traditional propulsion methods. In order...
Fingered robot hands are complicated systems made of three essential system components: its morphology, its actuation, and its software control. These system components are tightly coupled to each other. Due to this, it is hard to benchmark robot hand performance in a way to understand the contributions of the individual...
Fiber reinforced polymers have gained considerable attention due to their wide range of applications, leading to significative concerns for end-of-life recyclability and disposal. Natural fibers and recycled carbon fibers, coupled with thermoplastic matrices can provide a sustainable and environmentally friendly alternative to traditional materials.
This study focused on experimental materials...
This dissertation outlines the design and development of the first fully-soft, snake robot and its snake-inspired skin. Soft robotics takes advantage of soft materials to, among other things, improve robot interactions with complex, unstructured environments. Due to the interplay between the soft material and the environment, minor tweaks to the...
A Level 1 probabilistic risk assessment (PRA) is applied to a plutonium button-making process, but in regards to the risk of diversion (or theft) of special nuclear material (SNM) rather than the risk of mechanical failure. The main objective of the project was to identify the relative vulnerability of areas...
Ion therapy has long been investigated as a potential modality to improve cancer treatments beyond what is currently feasible with photon irradiations. Ions offer both a physical and biological advantage over photons. The physical advantages are well understood, ions deposit their maximum dose at defined penetration depths, allowing for minimal...
Adhesive use is becoming increasingly common in manufacturing processes. The advantage of adhesives are light weight components, non-destructive fastening techniques and distribution of loads over the applied bond region. Modeling the behavior of adhesive bond lines in fastening joints can help in the design process to make an optimized joint,...
Thin foil samples of special nuclear materials (SNMs) were irradiated for 60s using a Mark TRIGA II reactor, and their associated gamma emissions were recorded with a count time of 60s following irradiation. A rapid pneumatic transfer system was used to irradiate the samples in front of beam port #4....
Honeybees and honey combs are good indicators of environmental contamination and can be important for dose calculations. In the event of reactor accidents and nuclear weapon testing, the released radioactive materials are likely to be transported through various environmental pathways as well as by humans and animals, including bees. Due...
The Neutron radiography facility (NRF) at Oregon State University (OSU) has been modified to begin working on the non-destructive evaluation of concrete materials to study the early stages of shrinkage, cracking, and water transport of concrete during the curing process.
The objective of this work is to investigate the efficiency...
Chainsaws, an indispensable tool for modern forestry operations, rely on bar lubricant to prevent rapid wear of the chain and bar. Choice of bar lubricant must balance performance, cost, and biological impact. Many bar lubricants are available, but little published work exists that conclusively ranks the performance of these choices....
Numerous physical and chemical processes are required for successful ignition of a flammable mixture, many of which have been well characterized. However, one aspect of the ignition process that has received limited consideration is understanding the temperature of the spark kernel. A spark kernel is the volume of heated gas...
Formula SAE is a collegiate engineering competition that has participants from around the globe. Of the 1000 points available throughout the event, 100 (10%) are dedicated to the fuel efficiency of the student built race cars. Competition rules allow either gasoline or E85, a mix of 85% ethanol and 15%...
The recent reductions to the international dose limit recommendations for the lens
of the eye have renewed interest in radiation protection strategies in interventional
fluoroscopy, where eye-lens radiation exposure occurs frequently. Radiationshielding
eyewear can significantly reduce lens dose in these scenarios, but accurate
protection factors are elusive because they depend...
The International Commission on Radiological Protection (ICRP) has modeled twelve reference animal and plant (RAP) species using simple geometric shapes in Monte–Carlo (MCNP) based simulations. The focus has now shifted to creating voxel phantoms of each RAP to advance the understanding of radiation interactions in nonhuman biota. The work contained...
The objective of this thesis was to investigate the use of the Jacobian Free Newton Krylov Method (JFNK) with physics based preconditioning for solving coupled radiative transport and material energy balance. Modeling of these physics is important in inertial confinement fusion and other high energy density systems. In this thesis,...
One of the pervasive problems arising in our modern, digital world surrounds data breaches where an adversary, through zero-day exploitations, phishing, or old-fashioned social engineering attacks, gains access to a service’s data stores. Our society increasingly relies on these cloud-based services for everything from our taxes to personal communication. As...
Nickel (Ni)-based alloys with a high chromium (Cr) content are frequently employed in applications where elevated temperatures and/or corrosive environments are present due to their excellent corrosion resistance and mechanical properties. However, a gap exists around the formation, and kinetics of long-range order (LRO) Ni2Cr phase in both model binary...
The environmental impact of the nuclear industry has prompted the need for innovative remediation strategies and accurate radiological assessments. This paper synthesizes three studies that collectively explore the potential of endemic plant species for phytoremediation, the development of anatomically accurate phantoms for precise dosimetry calculations, and the critical evaluation of...
We present a method for deterministically solving the consistent temperature and frequency dependent phonon radiative transport problem. We use the single relaxation time (SRT) approximation in the Self-Adjoint Angular Flux (SAAF) form with discrete ordinates (S_N) angular discretization method and continuous finite element method (CFEM) for spatial discretization. Included are...
In this dissertation, we derive and implement a new transport-diffusion hybrid algorithm for solving thermal radiative transfer (TRT) problems. Using the method of nonlinear elimination (NLEM), the TRT system of equations can be written in terms of a transport equation with the absence of scattering and a diffusion equation. The...
Modern sensors are complex systems comprising multiple sub-systems such as transducers, analog and mixed-signal interface circuits, digital processing circuits, and packaging. Over the last few decades, innovations in these sub-systems combined with their increased integration in complementary metal-oxide semiconductor (CMOS) processes have led to the rapid growth in sensors for...
Cherenkov detectors have been developed and used in several fields since the discovery of Cherenkov radiation. They do have several advantages compared with other detector types, such as low noise due to the low-energy threshold of Cherenkov radiation, and short decay constant (on the order of picoseconds). However, the light...
Neutron radiography has been used to study cementitious materials. This thesis studies the impact of heavy water on both the rate of hydration and neutron radiography. The neutron attenuation coefficients of light and heavy water were measured. Cement pastes were made with both heavy and light water. The attenuation coefficients...
Emergence of highly accurate Convolutional Neural Networks (CNNs) with the capability to process large datasets, has led to their popularity in many applications, including safety/security-sensitive (e.g. disease recognition, self-driving cars). Despite the high accuracy of convolutional neural networks, they have been found to be susceptible to adversarial noise added to...
Breast cancer is the most common cancer among women as it accounts for about 25% of all female cancer cases. Studies have shown that early detection of breast cancer increases the chances of a positive prognosis amongst patients therefore it is crucial to provide accurate diagnosis tools in routine exams....