Digital Commons Network^™

Analytical Results For The Three-Body Radiative Attachment Rate Coefficient, With Application To The Positive Antihydrogen Ion H̄+, Jack C. Straton

Physics Faculty Publications and Presentations

To overcome the numerical difficulties inherent in the Maxwell–Boltzmann integral of the velocity-weighted cross section that gives the radiative attachment rate coefficient αRA for producing the negative hydrogen ion H⁻ or its antimatter equivalent, the positive antihydrogen ion H¯⁺ , we found the analytic form for this integral. This procedure is useful for temperatures below 700 K, the region for which the production of H¯⁺ has potential use as an intermediate stage in the cooling of antihydrogen to ultra-cold (sub-mK) temperatures for spectroscopic studies and probing the gravitational interaction of the anti-atom. Our results, utilizing a 50-term …

A Numerical Investigation Of Microgravity Evaporation, Daniel Peter Ringle

Dissertations and Theses

Evaporation is important to myriad engineering processes such as cooling, distillation, thin film deposition, and others. In fact, NASA has renewed interest in using cabin air pressure evaporation as a means to recycle waste water in space. As one example, NASA recently conducted experiments aboard the International Space Station (ISS) to measure evaporation rates in microgravity and to determine the impacts of porous structure on the process. It has long been assumed that differences in evaporation rates between 1-g₀ and microgravity are small. However, discrepancies by as much as 40% have been observed in practice. The assumption now …

An Analysis Of The Reactivation Potential Of A Deep-Seated Landslide In The Oregon Coast Range Under Varying Hydrologic Conditions With Seismic Triggering, Emily E. Smoot

Anthós

Landslides can occur in many locations across the world and have the potential to be extremely destructive if failures occur near populated areas. Failures are most likely to occur on slopes that have already experienced numerous failures. This means they are a considerable hazard, and the risk involved with building in areas that have previously experienced landslides should be adequately understood. This study examines the reactivation potential of a deep-seated landslide located in the Oregon Coast Range. The analysis of this landslide included creating a map of the surface morphology and computing the factor of safety for the deposit using …

Amplifying Latinx Voice Through Interview Study: Highlighting Mathematics Identity As A Pathway To Student Self-Empowerment And Academic Agency, Brea Justine Cohen

Dissertations and Theses

Nationally, the percentage of high school students taking higher-level mathematics courses (beyond Algebra 2) has increased from the late 20th century to the present. However, as compared to White high school students enrolled in advanced math classes, the rate is lower among students of color, specifically students who identify as Latinx, African American, or Native American. My school district (a suburban district in the Northwestern United States) is working to address this problem by implementing several district-wide initiatives that focus on increasing students' engagement in mathematics, which focuses teacher pedagogy on leveraging mathematics communities to support collaborative mathematics dialogue. The …

Water 4.0, Arthur Preston

OHSU-PSU School of Public Health Annual Conference

A review of local drinking water quality/technologies, and strategies to improve water quality using emerging next generation technology.

Aggregated Water Heater System (Awhs) Optimization For Ancillary Services, Manasseh Obi

Dissertations and Theses

In this dissertation, I present a two-stage optimization routine that schedules an Aggregated Water Heater System (AWHS) to concurrently provide three utility ancillary services, namely, frequency regulation, frequency response, and peak demand mitigation.

Water heaters can be controlled to manage their energy take, the amount of energy a water heater can absorb upon command. The AWHS is a model aggregation of thousands of water heaters, the energy take and power characteristics of which are based on U.S Census household data and usage behavior patterns. The aggregate energy take available in the AWHS may be dispatched en masse for participation in …

Unpacking The Process And Outcomes Of Ethical Markets: A Focus On Certified B Corporations, Renée Bogin Curtis

Dissertations and Theses

The growth in conscious consumption presents an opportunity to 1) better understand the potential outcomes of ethical market practices as a community-advocacy tool and 2) to consider potential policy considerations. The marketplace has increasingly become an arena for social action. This leads to the question of how can markets facilitate ethical business practices and community benefits? The recent rise of social benefit corporations warrants an evaluation of the outcomes of ethically-driven markets. Using a comparative research design and qualitative interview methods, this study examines certified Benefit Corporations (B Corps) in two selected cities: Philadelphia and Portland. Through interviews with B …

A Hybrid Lipid Membrane Coating “Shape-Locks” Silver Nanoparticles To Prevent Surface Oxidation And Silver Ion Dissolution, Thomas J. Miesen, Arek M. Engstrom, Dane C. Frost, Ramya Ajjarapu, Rohan Ajjarapu, Citlali Nieves Lira, Marilyn R. Mackiewicz

Chemistry Faculty Publications and Presentations

The controlled synthesis of stable silver nanoparticles (AgNPs), that do not undergo surface oxidation and Ag⁺ ion dissolution, continues to be a major challenge. Here the synthesis of robust hybrid lipid-coated AgNPs, comprised of L-α-phosphatidylcholine (PC) membranes anchored by a stoichiometric amount of long-chained hydrophobic thiols and sodium oleate (SOA) as hydrophobic binding partners, that do not undergo surface oxidation and Ag+ ion dissolution, is described. UV-Visible (UV-Vis) spectroscopy, transmission electron microscopy (TEM), and inductively coupled plasma mass spectrometry (ICP-MS) demonstrate that in the presence of strong oxidants, such as potassium cyanide (KCN), the hybrid lipid-coated AgNPs are stable …

Connected Vehicle System Design For Signalized Arterials, Xianfeng Terry Yang, Mingyue Ji, Qinzheng Wang

TREC Final Reports

It can be expected that connected vehicles (CVs) systems will soon go beyond testbed and appear in real-world applications. To accommodate a large number of connected vehicles on the roads, traffic signal control systems on signalized arterials would require supports of various components such as roadside infrastructure, vehicle on-board devices, an effective communication network, and optimal control algorithms. In this project, we aim to establish a real-time and adaptive system for supporting the operations of CV-based traffic signal control functions. The proposed system will prioritize the communication needs of different types of CVs and best utilize the capacity of the …

How Long Can Neoliberalism Withstand Climate Crisis?, Julius Mcgee, Patrick Greiner

Urban Studies and Planning Faculty Publications and Presentations

The climate crisis is proving to be antithetical to the neoliberal machines that define current forms of social organization. On the one hand, reducing fossil fuel consumption, the largest contributor to climate change, requires collaborative efforts. These efforts must take into consideration the foundational role of fossil fuels in modern economies. We must acknowledge, for instance, that most peoples’ livelihoods are tethered to fossil fuels, which recent studies have demonstrated is not the result of random historical development but deliberate policy.1 Fossil fuels continue to be used as a form of social domination—a means to expropriate productive and reproductive …

Soil Nitrogen Cycling Over Two Decades Following Calcium Treatment In Hubbard Brook Experimental Forest, Nh, Angelina Uribe

Environmental Science and Management Professional Master's Project Reports

A watershed-scale calcium addition experiment at Hubbard Brook Experimental Forest, New Hampshire, was performed in 1999 to better understand how forest ecosystem function and biogeochemistry are affected by changes in pH. Significant increases in forest growth and acid neutralizing capacity of the soil and stream water were reported in the six years following the calcium addition, but the expected stimulation of the nitrogen cycle was not observed. The aims of this study were to 1) examine the 20-year dataset of soil nitrogen dynamics following the experimental calcium addition in the treated watershed and paired reference area to understand longer term …

Scanning Electron Microscopy (Sem) Investigation Of Morphology Changes In The Reduction Of Silica Nanoparticles To Elemental Silicon, Allison M. Cairns

University Honors Theses

The application of silicon nanoparticles varies from energy storage materials, to drug-delivery, and molecular recognition. Various chemical and physical properties of the Si nanoparticles arise from their morphology. This paper aims to reveal the morphology of Si nanoparticles following magnesiothermic reduction of silica (SiO₂) nanoparticles. Two sets of SiO₂ nanoparticles were used, commercially available NanoXact nanoparticles and laboratory-synthesized Stöber nanoparticles. A Zeiss Sigma VP FEG SEM was used to examine the morphology. Following the magnesiothermic reduction, the nanoparticles were etched with HF. Ten sets of images were taken of both Stöber and NanoXact nanoparticles: 1,2: the SiO …

Workflow Critical Path: A Data-Oriented Path Metric For Holistic Hpc Workflows, Daniel D. Nguyen

Dissertations and Theses

Optimizing scientific application performance in HPC environments is a complicated task which has motivated the development of many performance analysis tools over the past decades. These tools were designed to analyze the performance of a single parallel code using common approaches such as message passing (MPI), multithreading (OpenMP), acceleration (CUDA), or a hybrid approach. However, current trends in HPC such as the push to exascale, convergence with Big Data, and growing complexity of HPC applications and scientific workflows, have created gaps that these performance tools do not cover, particularly involving end-to-end data movement through an end-to-end HPC workflow comprising multiple …

Multiple Diagram Navigation, Hisham Benotman

Dissertations and Theses

Domain novices learning about a new subject can struggle to find their way in large collections. Typical searching and browsing tools are better utilized if users know what to search for or browse to. In this dissertation, we present Multiple Diagram Navigation (MDN) to assist domain novices by providing multiple overviews of the content matter using multiple diagrams. Rather than relying on specific types of visualizations, MDN superimposes any type of diagram or map over a collection of documents, allowing content providers to reveal interesting perspectives of their content. Domain novices can navigate through the content in an exploratory way …

Extensible Performance-Aware Runtime Integrity Measurement, Brian G. Delgado

Dissertations and Theses

Today's interconnected world consists of a broad set of online activities including banking, shopping, managing health records, and social media while relying heavily on servers to manage extensive sets of data. However, stealthy rootkit attacks on this infrastructure have placed these servers at risk. Security researchers have proposed using an existing x86 CPU mode called System Management Mode (SMM) to search for rootkits from a hardware-protected, isolated, and privileged location. SMM has broad visibility into operating system resources including memory regions and CPU registers. However, the use of SMM for runtime integrity measurement mechanisms (SMM-RIMMs) would significantly expand the amount …

Examining Integration And Sense Of Belonging Among Undergraduate Students Participating In Stem Support Programs, Mackenzie J. Gray

University Honors Theses

National calls have been made to strengthen our nation’s Science, Technology, Engineering, and Mathematics (STEM) workforce by improving student preparation and increasing retention rates. A sense of belonging in STEM fields is thought to be key for persistence in STEM, but many students face academic, social, and financial barriers that can impede this sense of belonging. These barriers can be more pronounced for students underrepresented in STEM. In response, many federal and non-governmental agencies have invested in the future STEM workforce by funding STEM support programs. Such programs aim to support student persistence by providing academic, social, and financial resources …

Tending The Fire: Wildfire Risk Management At The Interface, Cody R. Evers

Dissertations and Theses

Escalating loss from wildfire in the American West has made clear the need to rethink wildfire risk, including how such risks result from the unique interaction of social and natural dynamics within the wildland urban interface. Unfortunately, techniques for studying these interactions remain limited. The intent of this research is to address this gap. In each of four chapters, I examine different aspects of wildfire risk management through a coupled human-natural lens. I document how wildfire activity has shifted over three decades across forest and shrubland systems in the western US and connect these changes to the simultaneous growth in …

Working Paper No. 43, Towards A Veblenian Theory Of Instincts, Duane Murray

Working Papers in Economics

This inquiry seeks to establish that in his writings, Thorstein Veblen offers a comprehensive and insightful contribution towards an understanding of instincts. Instincts can be viewed self-regarding and thought to promote the survival of the individual. Other instincts can be classified as group-regarding and contribute towards the continuation of society. Instincts can lead to the formation of habits and to combine to create societal institutions that govern human behavior. With the passage of time, instincts, habits, and institutions are thought to contribute to economic and societal evolution.

Modeling And Visualizing Power Amplification In Fiber Optic Cables, Gil Parnon

University Honors Theses

Transverse mode instability in fiber optic cables causes power amplification to exhibit chaotic behavior. Due to this, numerical modeling of fiber optic power amplification is extremely computationally expensive. In this paper I work through modeling similar behavior in a simpler system. I also visualize the three-dimensional phase portrait of the system in order to better understand the behavior and hopefully relate it to more well-understood problems.

Absorptive Reflectionless Filters, Guy Barry Lemire

Dissertations and Theses

For many applications requiring some sort of signal filtering or signal conditioning, the filter requirements are usually approached with a single purpose in mind, which is to maximize both passband signal amplitude and stop band signal attenuation to the load with little to no thought given to what happens to the stop band signal energy. Many conventional filters have very poor impedance matching in the stopband resulting in reflected energy or large return loss (S₁₁). This reflected energy can then cause interactions with adjoining system components which do not in general respond well to spurious reflected energy and …

Multilevel Spectral Coarsening For Graph Laplacian Problems With Application To Reservoir Simulation, Andrew T. Barker, Stephen V. Gelever, Chak Shing Lee, Sarah Osborn, Panayot S. Vassilevski

Mathematics and Statistics Faculty Publications and Presentations

We extend previously developed two-level coarsening procedures for graph Laplacian problems written in a mixed saddle point form to the fully recursive multilevel case. The resulting hierarchy of discretizations gives rise to a hierarchy of upscaled models, in the sense that they provide approximation in the natural norms (in the mixed setting). This property enables us to utilize them in three applications: (i) as an accurate reduced model, (ii) as a tool in multilevel Monte Carlo simulations (in application to finite volume discretizations), and (iii) for providing a sequence of nonlinear operators in a full approximation scheme for solving nonlinear …

Detecting Geomorphic Change And Stream Channel Evolution On The Sandy River, Oregon, Using Lidar Following Dam Removal In 2007, Lowell Henry Anthony

Dissertations and Theses

Following the removal of Marmot Dam on the Sandy River, Oregon, several Lidar flights were flown over the area of the former reservoir. The resultant sequential DEMs permitted calculation of reach-scale volumetric erosion and aggradation following dam removal. This allows for change detection across the entire affected reach of the former impoundment rather than just at several cross sections. In the first year there was a net loss of blank sediment in the dewatered reach. Subsequent flights show continued degradation of 145,649 m³ as well as aggradation of 6,232 m³. Sediment transport reached quasi-equilibrium in 2012 with …

Balancing Security, Performance And Deployability In Encrypted Search, David Joel Pouliot

Dissertations and Theses

Encryption is an important tool for protecting data, especially data stored in the cloud. However, standard encryption techniques prevent efficient search. Searchable encryption attempts to solve this issue, protecting the data while still providing search functionality. Retaining the ability to search comes at a cost of security, performance and/or utility.

An important practical aspect of utility is compatibility with legacy systems. Unfortunately, the efficient searchable encryption constructions that are compatible with these systems have been proven vulnerable to attack, even against weaker adversary models.

The goal of this work is to address this security problem inherent with efficient, legacy compatible …

Interactions Between The Azoarcus Ribozyme And Manganese (Ii) Divalent Cations, Joshua Martwick

University Honors Theses

The RNA world hypothesis suggests that RNA systems were the first form of life on the planet, beginning to appear approximately 4 billion years ago. Group I introns are self-splicing RNA elements in extant organisms and use Mg²⁺ as the principle divalent cation to promote catalysis. The group I intron ribozyme from Azoarcus is frequently used in origin of life studies, partially due to its autocatalytic abilities - the Azoarcus ribozyme is able to be broken into fragments and reassemble itself into its fully functional ribozyme. Previous work identified metal binding sites on the Azoarcus ribozyme which use both …

Power Efficiency Enhancement And Linearization Techniques For Power Amplifiers In Wireless Communications, Haider Al-Kanan

Dissertations and Theses

Wireless communication systems require Power Amplifiers (PAs) for signal transmissions. The trade-off between power efficiency and nonlinear distortion in PAs degrades the communication performance. Thus, power efficiency and nonlinearity are two main concerns of operating PAs in communication systems. Nonlinear behavioral models are typically used to quantify and mitigate the distortion effects of PAs on communication systems. This dissertation presents an estimation approach for modeling and linearizing the PA Amplitude-to-Amplitude (AM/AM) nonlinearity using the design specifications of PAs, such as gain, the third-order intercept point, and 1dB compression point. Furthermore, an enhanced approach for modeling solid-state power amplifiers is developed …

Minimum Complexity Echo State Networks For Genome And Sequence Analysis, Christopher John Neighbor

Dissertations and Theses

Increasing viral illnesses threatens global human health and welfare. Due to the distribution of disease and the expense of diagnosis, it is of value to develop portable assays that can detect viral infections early. DNA molecular logic technology offers a portable detection method due to the versatility and stability of DNA and the potential of in situ computation.

Top-down engineering of these chemical logic networks can be difficult due to the difficulties of their implementation using DNA as a substrate. In this work echo state networks, a form of recurrent neural networks, were explored with the motivation that their implementation …

Improved Denoising Of Structural Vibration Data Employing Bilateral Filtering, Ning Liu, Thomas Schumacher

Civil and Environmental Engineering Faculty Publications and Presentations

With the continuous advancement of data acquisition and signal processing, sensors, and wireless communication, copious research work has been done using vibration response signals for structural damage detection. However, in actual projects, vibration signals are often subject to noise interference during acquisition and transmission, thereby reducing the accuracy of damage identification. In order to effectively remove the noise interference, bilateral filtering, a filtering method commonly used in the field of image processing for improving data signal-to-noise ratio was introduced. Based on the Gaussian filter, the method constructs a bilateral filtering kernel function by multiplying the spatial proximity Gaussian kernel function …

Oregon City School District Enrollment Forecasts 2020-21 To 2029-30, Portland State University. Population Research Center, Charles Rynerson, Joshua Ollinger

School District Enrollment Forecast Reports

This report presents a range of three scenarios of district-wide enrollment forecasts by grade level for the Oregon City School District (OCSD) for the 10 year period between 2020-21 and 2029-30. Each enrollment forecast scenario is related to population forecasts that incorporate different assumptions about growth within the District, with the primary differences being the contribution of net migration to the District’s population and age distribution. Individual school forecasts consistent with the middle series are also presented for the 10 year period.

Some New Results On Stochastic Comparisons Of Coherent Systems Using Signatures, Ebrahim Amini-Seresht, Baha-Eldin Khaledi, Subhash C. Kochar

Mathematics and Statistics Faculty Publications and Presentations

We consider coherent systems with independent and identically distributed components. While it is clear that the system’s life will be stochastically larger when the components are replaced with stochastically better components, we show that, in general, similar results may not hold for hazard rate, reverse hazard rate, and likelihood ratio orderings. We find sufficient conditions on the signature vector for these results to hold. These results are combined with other well-known results in the literature to get more general results for comparing two systems of the same size with different signature vectors and possibly with different independent and identically distributed …

Toxic Ketene Gas Forms On Vaping Vitamin E Acetate Prompting Interest In Its Possible Role In The Evali Outbreak, Robert Strongin

Chemistry Faculty Publications and Presentations

Recent efforts by the Centers for Disease Control and Prevention (CDC), the US Food and Drug Administration (FDA), and state authorities have led to the determination that vitamin E acetate (VEA) is strongly associated with e-cigarette or vaping product use-associated lung injury (EVALI) (1). VEA has been found in nearly all patient lung fluid samples analyzed and not observed in lung fluid from healthy cohorts. Despite strong evidence linking VEA to EVALI, its putative role as a causative agent has yet to be determined. To address the key issue of whether VEA is a just marker or a significant mediator …