Digital Commons Network^™

Drafting In Self-Timed Circuits, Christopher Lee Cowan

Dissertations and Theses

Intervals between data items propagating in self-timed circuits are controlled by handshake signals rather than by a clock. In many self-timed designs, a trailing data item will catch up with a leading item or token, even when it trails by thousands of gate delays. This effect, called "drafting," can be seen in many of the self-timed designs, e.g., GasP, Mousetrap, Click, and Micropipeline. The purpose of this dissertation is to reveal the circuit mechanism of drafting in self-timed circuits typically used in FIFO stages. Drafting is usually considered to be incidental to the operation of self-timed circuits since interval timing …

Discretization Of The Hellinger-Reissner Variational Form Of Linear Elasticity Equations, Kevin A. Sweet

REU Final Reports

This paper addresses the derivation of the Hellinger-Reissner Variational Form from the strong form of a system of linear elasticity equations that are used in relation to geological phenomena. The problem is discretized using finite element discretization. This allowed the creation of a program that was used to run tests on various domains. The resultant displacement vectors for tested domains are shown at the end of the paper.

Trefftz Finite Elements On Curvilinear Polygons, Akash Anand, Jeffrey S. Ovall, Samuel E. Reynolds, Steffen Weisser

Mathematics and Statistics Faculty Publications and Presentations

We present a Trefftz-type finite element method on meshes consisting of curvilinear polygons. Local basis functions are computed using integral equation techniques that allow for the efficient and accurate evaluation of quantities needed in the formation of local stiffness matrices. To define our local finite element spaces in the presence of curved edges, we must also properly define what it means for a function defined on a curved edge to be "polynomial" of a given degree on that edge. We consider two natural choices, before settling on the one that yields the inclusion of complete polynomial spaces in our local …

Family Math Night: Increasing Engagement In University Mathematics Courses For Prospective Teachers, Eva Thanheiser

Mathematics and Statistics Faculty Publications and Presentations

Prospective elementary school teachers (PSTs) often do not perceive mathematics activities as fun or engaging and perceive the mathematics tasks in their university content courses as inauthentic and irrelevant. Both these points were addressed by connecting the university classroom tasks to the K–5 environment via a Family Math Night (FMN). Survey results from 23 PSTs showed that PSTs were excited about the authenticity of the tasks, learned about children’s mathematical thinking, and reconceptualized mathematics learning as potentially enjoyable. In combination, these results may lead to PSTs’ increased engagement in the mathematics content course and, thus, result in their increased mathematics …

Toxic Chemical Governance Failure In The United States: Key Lessons And Paths Forward, Ariana M. Chiapella, Zbigniew Grabowski, Mary Ann Rozance, Ashlie D. Denton, Manar A. Alattar, Elise F. Granek

Environmental Science and Management Faculty Publications and Presentations

Over 40 years of regulations in the United States have failed to protect human and environmental health. We contend that these failures result from the flawed governance over the continued production, use, and disposal of toxic chemicals. To address this failure, we need to identify the broader social, political, and technological processes producing, knowing, and regulating toxic chemicals, collectively referred to as toxic chemical governance. To do so, we create a conceptual framework covering five key domains of governance: knowledge production, policy design, monitoring and enforcement, evaluation, and adjudication. Within each domain, social actors of varying power negotiate what constitutes …

The Fourier Spectrum Of A Singing Wine Glass, Reuben Leatherman, Justin Charles Dunlap, Ralf Widenhorn

Physics Faculty Publications and Presentations

The phenomenon of the singing wineglass is familiar to many. Most people have run a finger along the rim of a wine glass with the right speed and pressure to get it to whistle a tone or perhaps heard a glass harmonica being played. However, have you ever noticed and wondered why the vibrations caused by a finger on a glass produce a pulsating sound, rather than a steady, constant-amplitude vibration? Further exploration reveals that the sound and pulsations of a wine glass vary depending on the way the wine glass is stimulated. In this paper, we investigate and model …

Approximate Pattern Matching Using Hierarchical Graph Construction And Sparse Distributed Representation, Aakanksha Mathuria, Dan Hammerstrom

Electrical and Computer Engineering Faculty Publications and Presentations

With recent developments in deep networks, there have been significant advances in visual object detection and recognition. However, some of these networks are still easily fooled/hacked and have shown “bag of features” failures. Some of this is due to the fact that even deep networks make only marginal use of the complex structure that exists in real-world images, even after training on huge numbers of images. Biology appears to take advantage of such a structure, but how? In our research, we are studying approaches for robust pattern matching using still, 2D Blocks World images based on graphical representations of the …

Estimation Of Association Between A Longitudinal Marker And Interval-Censored Progression Times, Naghmeh Daneshi

Dissertations and Theses

In longitudinal studies, we observe the subjects who are likely to progress to a new state during the study time. For example, in clinical trials the stage of a progressing disease is recorded at each follow-up visit. The primary goal is to estimate the relationship between the attributes and the subject's progression state. In such studies, some subjects complete all their follow-up visits and their progression state are observed without any missingness. However, others miss their follow-up visits and when they come back, they learn that they have progressed to a new state. In this case, not only are their …

A Secure Anti-Counterfeiting System Using Near Field Communication, Public Key Cryptography, Blockchain, And Bayesian Games, Naif Saeed Alzahrani

Dissertations and Theses

Counterfeit products, especially in the pharmaceutical sector, have plagued the international community for decades. To combat this problem, many anti-counterfeiting approaches have been proposed. They use either Radio Frequency Identification (RFID) or Near Field Communication (NFC) physical tags affixed to the products. Current anti-counterfeiting approaches detect two counterfeiting attacks: (1) modifications to a product's tag details, such as changing the expiration date; and (2) cloning of a genuine product's details to reuse on counterfeit products. In addition, these anti-counterfeiting approaches track-and-trace the physical locations of products as the products flow through supply chains.

Existing approaches suffer from two main drawbacks. …

Versatile Binary-Level Concolic Testing, Bo Chen

Dissertations and Theses

Computing systems are experiencing an explosive growth, both in complexities and diversities, ushered in by the proliferation of cloud computing, mobile computing, and Internet of Things. This growth has also exposed the consequences of unsafe, insecure, and unreliable computing systems. These all point to the great needs of sophisticated system validation techniques. Recent advances in research on symbolic execution has shown great promises for automated software analysis, e.g., generating test cases, finding bugs, and detecting security vulnerabilities. However, symbolic execution is mostly adopted to analyze user applications, while modern computing systems in practice consist of many components shipped by various …

Design Of A Canine Inspired Quadruped Robot As A Platform For Synthetic Neural Network Control, Cody Warren Scharzenberger

Dissertations and Theses

Legged locomotion is a feat ubiquitous throughout the animal kingdom, but modern robots still fall far short of similar achievements. This paper presents the design of a canine-inspired quadruped robot named DoggyDeux as a platform for synthetic neural network (SNN) research that may be one avenue for robots to attain animal-like agility and adaptability. DoggyDeux features a fully 3D printed frame, 24 braided pneumatic actuators (BPAs) that drive four 3-DOF limbs in antagonistic extensor-flexor pairs, and an electrical system that allows it to respond to commands from a SNN comprised of central pattern generators (CPGs). Compared to the previous version …

Design And Experimental Evaluation Of Deepmarket: An Edge Computing Marketplace With Distributed Tensorflow Execution Capability, Soyoung Kim

Dissertations and Theses

There is a rise in demand among machine learning researchers for powerful computational resources to train complex machine learning models, e.g., deep learning models. In order to train these models in a reasonable amount of time, the training is often distributed among multiple machines; yet paying for such machines (either through renting them on cloud data centers or building a local infrastructure) is costly. DeepMarket attempts to reduce these costs by creating a marketplace that integrates multiple computational resources over a distributed TensorFlow framework. Instead of requiring users to rent expensive GPU/CPUs from a third-party cloud provider, DeepMarket allows users …

Are We Providing Preferred Floral Resources For Bees In Our Neighborhoods? : Assessing The Relationship Between Small Scale Vegetation Metrics And Bee Presence In Se Portland, Hailey Wallace

Dissertations and Theses

Bee pollinators can thrive in highly urbanized environments if their preferred floral resources and habitat types are available. Enhanced pollinator habitats are being created globally, with a large local effort in Portland, Oregon. This project determined if we were providing the most preferred floral resources at enhanced pollinator sites for bees, if floral resources were available throughout the season, and if differences in dietary preferences between native and honey bees would allow for the identification of "native bee floral resources" in South East Portland. Bee pollinators were monitored from June to August at three enhanced pollinator sites in South East …

Introducing Cornerstone Courses Into Electrical And Computer Engineering Curriculum, Branimir Pejcinovic

Electrical and Computer Engineering Faculty Publications and Presentations

Almost all engineering programs have some form of final, culminating design experience, which is typically taught as a senior year capstone design course. Due to ABET requirements these are team and project based. Many programs will also have projects interspersed among required and elective courses, but these tend to be overrepresented in freshman year. We have recently introduced a set of courses during sophomore year that mimic our approach to capstone courses and provide authentic engineering design experience. These so-called cornerstone courses provide scaffolding by introducing all of the components of teamwork and design process but in a less formal …

Regional Modeling Of The Glaciers Of The North Cascades Mountains, Washington, Usa, Christina Eileen Gray

Dissertations and Theses

Glaciers in the North Cascades store winter snowfall as ice and release it in late summer as melt, providing an important regional source of water and hydroelectric energy. The future of glaciers in the North Cascades, Washington, were evaluated using a regional glaciation model driven by the Community Climate System Model 4 global climate model. The climate model was coupled with three Representative Concentration Pathways (RCPs), 2.6, 4.5, and 8.5. These RCPs provide a business-as-usual scenario (RCP 8.5), which assumes society makes little to no efforts to reduce greenhouse gas emissions, a best-case scenario (RCP 2.6) with strong attempts to …

Psu Green Building Internship Final Report, 2019: Karl Miller Center Post-Occupancy Study, Everett Stilley, Junyoung Lee

Campus Sustainability Office Publications, Reports and Presentations

This study examined the effectiveness of the passive cooling strategies in the Karl Miller Center (KMC) at Portland State University. Due to the warm temperatures reached in Portland during the summer months and the absence of a mechanical cooling system on the Pavilion side of the KMC, classrooms can exceed thermal comfort preferences on a number of occasions. Previous studies have recommended taking certain classrooms “offline” after 12pm in the summer, where they are only available for morning classes. This study aimed to update the classroom prioritization as well as analyze the employed cooling strategies and begin a long term …

Data From: Microplastic Concentrations In Two Oregon Bivalve Species: Spatial, Temporal, And Species Variability, Britta Baechler, Elise F. Granek, Matthew V. Hunter, Kathleen E. Conn

Environmental Science and Management Datasets

Microplastics are an ecological stressor with implications for ecosystem and human health when present in seafood. We quantified microplastic types, concentrations, anatomical burdens, geographic distribution, and temporal differences in Pacific oysters (Crassostrea gigas) and Pacific razor clams (Siliqua patula) from 15 Oregon coast, U.S.A. sites. Organisms were chemically digested and visually analyzed for microplastics, and material type was determined using Fourier Transform Infrared Spectroscopy. Microplastics were present in organisms from all sites. On average, whole oysters and razor clams contained 10.95 ± 0.77 and 8.84 ± 0.45 microplastic pieces per individual, or 0.35 ± 0.04 and …

Rare, Threatened And Endangered Species Of Oregon (2019), Jimmy Kagan, Sue Vrilakas, Eleanor P. Gaines, Lindsey K. Wise, Michael Russell, Cayla Sigrah

Institute for Natural Resources Publications

The Oregon Biodiversity Information Center (ORBIC) is part of the Institute for Natural Resources (INR) located at Portland State University (PSU). ORBIC maintains extensive databases of Oregon biodiversity, concentrating on rare and endangered plants, animals and ecosystems. Since its creation in 1979 as the Oregon Natural Heritage Program, ORBIC has been part of the Natural Heritage network. ORBIC is a constituent member of NatureServe, a non-profit organization with a mission to provide the scientific basis for effective conservation action. NatureServe and Oregon manage data using standards and protocols used across the U.S., Canada, and much of Latin America.

ORBIC has …

Multiwavelength Digital Holographic Imaging And Phase Unwrapping Of Protozoa Using Custom Fiji Plug-Ins, David Cohoe, Iulia Hanczarek, J. Kent Wallace, Jay Nadeau

Physics Faculty Publications and Presentations

Multiwavelength digital holographic microscopy (DHM) has been used to improve phase reconstructions of digital holograms by reducing 2p phase ambiguities. However, most samples used as test images have been solid or adhered to a surface, making it easy to determine focal planes and correct for chromatic aberration. In this study we apply 3-wavelength off-axis DHM to swimming protozoa containing distinct spectral features such as chlorophyll and carotenoids. We reconstruct the holograms into amplitude and phase images using the angular spectrum method. Methods for noise subtraction, chromatic aberration correction, and image registration are presented for both amplitude and phase. Approaches to …

A Resource Constrained Shortest Paths Approach To Reducing Personal Pollution Exposure, Elling Payne

REU Final Reports

As wildfires surge in frequency and impact in the Pacific Northwest, in tandem with increasingly traffic-choked roads, personal exposure to harmful airborne pollutants is a rising concern. Particularly at risk are school-age children, especially those living in disadvantaged communities near major motorways and industrial centers. Many of these children must walk to school, and the choice of route can effect exposure. Route-planning applications and frameworks utilizing computational shortest paths methods have been proposed which consider personal exposure with reasonable success, but few have focused on pollution exposure, and all have been limited in scalability or geographic scope. This paper addresses …

Navigating Around Convex Sets, J. J. P. Veerman

Mathematics and Statistics Faculty Publications and Presentations

We review some basic results of convex analysis and geometry in Rn in the context of formulating a differential equation to track the distance between an observer flying outside a convex set K and K itself.

2019 Commencement Program, Israel Bayer, Doreen Dodgen-Magee, Yasuhisa Iida, Rick Miller, Nanette Reid

Commencement Archives 2010-19

The program for the Portland State University 2019 Commencement ceremonies, held June 14, 15, and 16, 2019.

Doreen Dodgen-Magee gave the commencement address to the Graduate School of Education ceremony on June 14, 2019.

Rick Miller, Yasuhisa "Yaz" Iida, and Nanette Reid delivered keynote addresses to the School of Business ceremonies on June 15, 2019.

Israel Bayer gave the commencement address and received an honorary doctorate during the Professional Schools ceremony on June 16, 2019.

Working Paper No. 26, Basic Tenets Of The Austrian School Of Economics, Vladislav Yurlov

Working Papers in Economics

The Austrian school of economic thought has offered many ideas throughout its more than century old history. Beginning with Carl Menger’s Principles of Economics, the focus of this school dealt with individuals acting in a society for the benefit of everyone. With liberalism at their core, thinkers such as Friedrich von Wieser, Ludwig von Mises, and Friedrich Hayek saw economics as a practical approach to living. This inquiry seeks to establish that the Austrian school of economics advanced basic tenets. Building off of, and often creating their own ideas, Austrian economists gave rise to the principles of marginalism, significance …

Working Paper No. 15, Jevons’ Selective Interpretation Of Bentham, Devin Bales

Working Papers in Economics

This inquiry seeks to establish that in The Theory of Political Economy, W. Stanley Jevons offers a selective interpretation of Jeremy Bentham’s notion of utility. Moreover, Jevons does so in a manner that generates enduring implications for Economics as a science. Special emphasis is placed upon Jevons’ use of Bentham’s understanding of the circumstances that direct pursuits of pleasure and avoidance of pain. Emphasized is that Jevons’ omission of ‘fecundity, purity, and extent’ as quantifiers of utility, creates enduring implications that emerged years after his book’s publication in 1871. What is finally considered are some of the difficulties associated …

Working Paper No. 17, William Petty And Political Economy, Clarissa Allen

Working Papers in Economics

This inquiry seeks to establish that during the first part of the 1600s, William Petty generated original contributions to political economy. Subsequent to the Irish rebellion and in the wake of the English occupation of Ireland, Petty led a team of surveyors for measuring out areas of Ireland. The survey that he led mapped selected territories and detailed numerous characteristics, thus employing an early, rudimentary, but highly insightful census method. Petty sought to describe his world objectively and quantitatively through the use of numbers, weights, and measures – rather than subjectively. Petty developed a method of calculation still famously known …

Working Paper No. 18, Thomas Piketty On Capital And Inequality, Max Randall

Working Papers in Economics

This inquiry seeks to establish that, in his Capital in the Twenty-First Century, Thomas Piketty advances ideas concerning the origins and implication of economic inequality. Piketty commences his inquiry by considering and detailing wage differences amongst distinct classes of society. This mechanism for the distribution of income is compared across selected nations, and the differing tendencies over time are examined in detail. Distinct from working wages, Piketty considers income effects associated with capital ownership. Adding to this, Piketty shows that effects of inheritance need be considered as capital is passed to successive generations, thereby allowing the accruing of monetary …

Working Paper No. 33, Behavioral Assumptions In Jevons And Menger, Yvan Saastamoinen

Working Papers in Economics

In their key works, W. Stanley Jevons (1835-1882) and Carl Menger (1840-1921) introduce crucial behavioral assumptions as these relate to individual and aggregate economic activity. The assumptions found in Jevons’ work primarily focus on the ‘Pain and Pleasure Principle’, originally established by Jeremy Bentham, and how the human characteristic of inevitable variability interacts with basic needs. Subsequently, Menger’s contribution is centered on the idea that the value of a good is inherently subjective and also dependent upon human variability. This inquiry, therefore, seeks to establish that Jevons’ and Menger’s behavioral assumptions led to their being classified as early ‘behavioral’ economists. …

Board 63: Work In Progress: Adapting Scrum Project Management To Ece Courses, Branimir Pejcinovic, Phillip Wong, Robert B. Bass

Electrical and Computer Engineering Faculty Publications and Presentations

Scrum is a popular form of Agile project management. Its applications now include diverse areas such as software development, engineering, urban planning, and law. Scrum has also been used in software engineering educational programs, but its use in other engineering education is lagging. Within our electrical and computer engineering program, we introduced Scrum to help students improve their teamwork efficacy in projects and courses. Earlier, we have presented some initial experiences and observations when implementing Scrum in ECE courses. In this paper we will elaborate on how Scrum is applied across different years and how we scaffold student learning. Scrum …

Impulsivity In Science: Students' Beliefs In Their Science Abilities With And Without Adhd Symptomology, Deza'rae M. Collins, Lisa Marriott

University Honors Theses

Impulsivity has been negatively associated with students’ beliefs in their abilities in science (e.g., science self-efficacy). Impulsivity and risk tasking are known to be characteristics of Attention Deficit Hyperactivity Disorder (ADHD), but it is unknown whether science self-efficacy is altered in students exhibiting ADHD symptomology. STEM beliefs (i.e. science, technology, engineering, and math) were hypothesized to be more challenging for impulsive and risky students who exhibited symptoms of ADHD, since that the fields require the practice of repetitive tasks and coordinated attention to task performance. Impulsivity, ADHD symptomology, and risk taking behavior were assessed in a cross-sectional sample of 612 …

Use Of Connectotyping On Task Fmri Data Reveals Dynamic Network Level Cross Talking During Task Performance, Valeria Vazquez-Trejo, Binyam Nardos Phd, Bradley Schlaggar Md, Phd, Damien Fair Pa-C, Phd, Oscar Miranda-Dominguez Phd

University Honors Theses

Task functional MRI (fMRI) has greatly impacted our understanding of brain functioning, enabling the identification of brain areas associated with particular tasks. Current methods of fMRI analysis only display regional differences in activation. We propose that there are also dynamic functional connectivity changes occurring between systems which support the performance of a task.

A recently developed method, termed connectotyping, is able to efficiently model functional brain connectivity and has the potential to track changes in brain dynamics in individuals. Our work aims to use connectotyping to reveal the progression of temporal brain connectivity patterns in task fMRI.

Twenty-four participants (12 …