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Portland State University

2021

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Articles 91 - 115 of 115

Full-Text Articles in Engineering

The Critical Energy Infrastructure (Cei) Hub: A Look Into The Seismic Fragility Of Oregon’S Fuel, Annecy Bal Apr 2021

The Critical Energy Infrastructure (Cei) Hub: A Look Into The Seismic Fragility Of Oregon’S Fuel, Annecy Bal

Civil and Environmental Engineering Undergraduate Honors Theses

This research evaluates the seismic vulnerability of the Critical Energy Infrastructure (CEI) Hub and the associated fuel repercussions for the expected 9.0 magnitude earthquake along the Cascadia Subduction Zone. The tanks in the CEI hub are analyzed based on size and content. The owners and secondary containment areas are discussed using the same parameters. Various analysis techniques are reviewed to determine the most appropriate seismic fragility estimate for the site. The seismic vulnerability is analyzed using fragility curves by Hazus, American Lifeline Alliance, and D'Amico. The fragility curves are applied to the CEI Hub to determine expected damage and the …


The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, Stefan A. Talke, Ramin Familkhalili, David A. Jay Apr 2021

The Influence Of Channel Deepening On Tides, River Discharge Effects, And Storm Surge, Stefan A. Talke, Ramin Familkhalili, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

We combine archival research, semi-analytical models, and numerical simulations to address the following question: how do changes to channel geometry alter tidal properties and flood dynamics in a hyposynchronous, strongly frictional estuary with a landward decay in tidal amplitudes? Records in the Saint Johns River Estuary since the 1890s show that tidal range has doubled in Jacksonville, Florida. Near the estuary inlet, tidal discharge approximately doubled but tidal amplitudes increased only ~6%. Modeling shows that increased shipping channel depths from 5-6 to ~13m drove the observed changes, with other factors like channel shortening and width reduction producing comparatively minor effects. …


A Comparison Of Particulate Matter Deposition Onto Green Roof Species And White Roof In Portland, Oregon, Amelia Drake Apr 2021

A Comparison Of Particulate Matter Deposition Onto Green Roof Species And White Roof In Portland, Oregon, Amelia Drake

University Honors Theses

This study explores the following question: how do different green roof vegetation species contribute to particulate matter deposition relative to a white roof in Portland, Oregon? To answer this question, rinse water from two species of vegetation and rinse water from a white roof were filtered to measure the mass of particles found on these leaves. Leaf area was then determined in order to calculate the density of particles found on each surface. The resulting conclusions from this process clearly indicate that a larger density of particles collected on vegetative surfaces as opposed to the surface of the white roof. …


On Ip2 Impact To Nonlinear Distortion Of Rf Amplifiers, Xianzhen Yang, Shiyu Li, Siyuan Yan, Fu Li Mar 2021

On Ip2 Impact To Nonlinear Distortion Of Rf Amplifiers, Xianzhen Yang, Shiyu Li, Siyuan Yan, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

The second-order distortion, often using second-order intercept point (IP2) as an indicator, has been considered easy to be filtered in narrowband radio frequency (RF) communications because it is located far away from the passband of transmitted signals. However, with rapidly increased applications in wideband RF communications, the secondorder intermodulation (IM) might become important, partially evidenced by the increased appearances of IP2 in the amplifier datasheets in recent years. In this article, a power spectrum model of the second-order IM is derived to quantify the second-order distortion using the IP2. This model could be used to determine under what conditions, in …


An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb Mar 2021

An Analysis Of Suspended Sediment Dynamics In A Partially Mixed Estuary, Riyadh Hamad Muttaleb

Dissertations and Theses

The purpose of this work is to investigate via data analysis and numerical modeling the SPM (suspended particulate matter) dynamics of a heavily contaminated partially urban estuary, the Lower Passaic River estuary (LPR), NJ. Accordingly, I investigate the quantity and mechanics of variation of fine and coarse SPM in the LPR via data analysis. Data analysis focuses on the parameters that affect SPM dynamics at six moored stations occupied during the Fall and Spring seasons, from near the estuary mouth to tidal freshwater. A 3D hydrodynamic model (Delft3D-FM) is used to analyze the effects of estuary topography on the dynamic …


Memristor Crossbar Array Testing Using Sneak Paths, Rasika Dhananjay Joshi Mar 2021

Memristor Crossbar Array Testing Using Sneak Paths, Rasika Dhananjay Joshi

Dissertations and Theses

Moore's law decline has paved the way to shift to new technologies at architectural and device levels. CMOS based technologies are facing many challenges with the growing demand for miniaturization. The growing heat dissipation is the major limitation for performance, energy efficiency and reliability with the increasing transistor count in integrated circuits. Manufacturing costs and process/memory performance gap have also grown steadily over the last several decades with the scaling down of the CMOS feature size. Memristor, a nanoscale device, has the potential to address the CMOS limitations because of its non-volatility, high density, low power operation, low cost per …


Evolving Tides Aggravate Nuisance Flooding Along The U.S. Coastline., Sida Li, Thomas Wahl, Stefan A. Talke, David A. Jay, Philip M. Orton, Xinghui Liang, Guocheng Wang, Lintao Liu Mar 2021

Evolving Tides Aggravate Nuisance Flooding Along The U.S. Coastline., Sida Li, Thomas Wahl, Stefan A. Talke, David A. Jay, Philip M. Orton, Xinghui Liang, Guocheng Wang, Lintao Liu

Civil and Environmental Engineering Faculty Publications and Presentations

Nuisance flooding (NF) is defined as minor, nondestructive flooding that causes substantial, accumulating socioeconomic impacts to coastal communities. While sea-level rise is the main driver for the observed increase in NF events in the United States, we show here that secular changes in tides also contribute. An analysis of 40 tidal gauge records from U.S. coasts finds that, at 18 locations, NF increased due to tidal amplification, while decreases in tidal range suppressed NF at 11 locations. Estuaries show the largest changes in NF attributable to tide changes, and these can often be traced to anthropogenic alterations. Limited long-term measurements …


The Corrosion Of Stainless Steel Made By Additive Manufacturing: A Review, Gyeongbin Ko, Wooseok Kim, Kyungjung Kwon, Tae-Kyu Lee Mar 2021

The Corrosion Of Stainless Steel Made By Additive Manufacturing: A Review, Gyeongbin Ko, Wooseok Kim, Kyungjung Kwon, Tae-Kyu Lee

Mechanical and Materials Engineering Faculty Publications and Presentations

The advantages of additive manufacturing (AM) of metals over traditional manufacturing methods have triggered many relevant studies comparing the mechanical properties, corrosion behavior, and microstructure of metals produced by AM or traditional manufacturing methods. This review focuses exclusively on the corrosion property of AM-fabricated stainless steel by comprehensively analyzing the relevant literature. The principles of various AM processes, which have been adopted in the corrosion study of stainless steel, and the corrosion behaviors of stainless steel depending on the AM process, the stainless steel type, and the corrosion environment are summarized. In this comprehensive analysis of relevant literature, we extract …


Power Distribution System Tools For Analyzing Impacts Of Projected Electric Vehicle Load Growth Using Gridlab-D, Shahad Alomani Feb 2021

Power Distribution System Tools For Analyzing Impacts Of Projected Electric Vehicle Load Growth Using Gridlab-D, Shahad Alomani

Dissertations and Theses

The increased penetration of Electric Vehicle (EV) will provide substantial benefits to the environment. However, each EV will present a significant additional load to electric power distribution infrastructure, especially to radial distribution feeders. The additional load may cause transformers to operate beyond their thermal limits, unacceptable voltage drops along distribution lines, and primary conductor overloads. It is now, more than ever, vital to understand the limitations of existing infrastructure in light of an accelerating push for greener alternatives with insight that stems from modeling, simulation, and proper analysis as the backbone to a well-informed response.

The objective of this work …


The Hot Cracking Susceptibility Subjected The Laser Beam Oscillation Welding On 6xxx Aluminum Alloy With A Partial Penetration Joint, Minjung Kang, Jason Cheon, Dong Hyuck Kam, Cheolhee Kim Feb 2021

The Hot Cracking Susceptibility Subjected The Laser Beam Oscillation Welding On 6xxx Aluminum Alloy With A Partial Penetration Joint, Minjung Kang, Jason Cheon, Dong Hyuck Kam, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

A laser beam oscillation method using Galvano mirrors, which allows wide weld beads and controls thermal stress distribution, was suggested to suppress the formation of solidification cracks in laser welds. In order to understand the solidification cracking behavior in relation to the bead shape, laser beam oscillation welding was performed under various oscillation widths and frequency conditions. To evaluate the effect of the oscillation parameter on solidification cracking susceptibility, a regression analysis based on the shape of the bead was performed. Stress distribution generated during the laser beam oscillation welding process was also analyzed using finite element modeling simulation. From …


Modeling The Effectiveness Of Cooling Trenches For Stormwater Temperature Mitigation, Scott A. Wells Jan 2021

Modeling The Effectiveness Of Cooling Trenches For Stormwater Temperature Mitigation, Scott A. Wells

Civil and Environmental Engineering Faculty Publications and Presentations

Due to elevated runoff stormwater temperatures from impervious areas, one management strategy to reduce stormwater temperature is the use of underground flow through rock media termed a cooling trench. This paper examines the governing equations for the liquid phase and media phases for modeling the temperature leaving a cooling trench assuming that changes in temperature occurred longitudinally through the cooling trench. This model is dependent on parameters such as the media type, porosity, media initial temperature, inflow rate, and inflow temperature. Several approaches were explored mathematically for evaluating the change in temperature of the water and the cooling trench media. …


Automated Test Generation For Validating Systemc Designs, Bin Lin Jan 2021

Automated Test Generation For Validating Systemc Designs, Bin Lin

Dissertations and Theses

Modern system design involves integration of all components of a system on a single chip, namely System-on-a-Chip (SoC). The ever-increasing complexity of SoCs and rapidly decreasing time-to-market have pushed the design abstraction to the electronic system level (ESL), in order to increase design productivity. SystemC is a widely used ESL modeling language that plays a central role in modern SoCs design process. ESL SystemC designs usually serve as executable specifications for the subsequent SoCs design flow. Therefore, undetected bugs in ESL SystemC designs may propagate to low-level implementations or even final silicon products. In addition, modern SoCs design often involves …


Accuracy Assessment Of Global Internal-Tide Models Using Satellite Altimetry, Loren Carrere, Brian K. Arbic, Brian Dushaw, Gary D. Egbert, Svetlana Erofeeva, Florent Lyard, Richard D. Ray, Clément Ubelmann, Edward Zaron, Zhongxiang Zhao, Jay F. Shriver, Maarten C. Buijsman, Nicolas Picot Jan 2021

Accuracy Assessment Of Global Internal-Tide Models Using Satellite Altimetry, Loren Carrere, Brian K. Arbic, Brian Dushaw, Gary D. Egbert, Svetlana Erofeeva, Florent Lyard, Richard D. Ray, Clément Ubelmann, Edward Zaron, Zhongxiang Zhao, Jay F. Shriver, Maarten C. Buijsman, Nicolas Picot

Civil and Environmental Engineering Faculty Publications and Presentations

Altimeter measurements are corrected for several geophysical parameters in order to access ocean signals of interest, like mesoscale or sub-mesoscale variability. The ocean tide is one of the most critical corrections due to the amplitude of the tidal elevations and to the aliasing phenomena of high-frequency signals into the lower-frequency band, but the internal-tide signatures at the ocean surface are not yet corrected globally.

Internal tides can have a signature of several centimeters at the surface with wavelengths of about 50–250 km for the first mode and even smaller scales for higher-order modes. The goals of the upcoming Surface Water …


Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young Jan 2021

Mit-S1 Constitutive Model Calibration For A Portland-Area Soil, Steven Ryan Young

Dissertations and Theses

Soils that are intermediate to sands and clays are a challenge for geotechnical engineers since most methods for interpreting soil properties or soil behaviors are based on sands or clays and do not address behaviors of intermediate soils. This is a particular challenge for engineers in the Portland-area where many of the major soil units are composed of intermediate soils. Analysis of intermediate soils is further challenged since many standard constitutive models are based on sandy or clay-like soils. However, the MIT-S1 constitutive model is capable of capturing intermediate soil behavior. A calibration of the MIT-S1 constitutive model for Portland-area …


Methods For Object Tracking With Machine Vision, Zachary Simon Stamler Jan 2021

Methods For Object Tracking With Machine Vision, Zachary Simon Stamler

Dissertations and Theses

As machine learning and deep learning systems continue to find applications in science and engineering, the problem of providing these systems with high-quality data continues to increase in importance. Many of these systems utilize machine vision as their primary source of information, and in order to maximally leverage their abilities it is important to be able to provide them with high quality, accurate data. Unfortunately, many sets of tracking data extracted from video suffer from the problem of missing frames, which can arise from a multitude of causes depending on the system. These missing frames can result in confusion between …


Implementation Of A Novel Inertial Mass System And Comparison To Existing Mass-Rig Systems For Shake Table Experiments, Alvaro Lopez, Peter Dusicka Jan 2021

Implementation Of A Novel Inertial Mass System And Comparison To Existing Mass-Rig Systems For Shake Table Experiments, Alvaro Lopez, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

Shake table testing is one of the more effective experimental approaches used to study and evaluate seismic performance of structures. Reduced-scale models can still result in large-scale specimens where incorporating the required inertial mass effectively and safely can be challenging. This study proposes a new system of arranging the mass in the experiments that combines the realism of mass participation during earthquake excitation when supported by the shake table with laboratory practicality considerations of the mass positioned off the specimen. The characteristics and dynamic motion equations for the proposed system are described and applied to shake table experiments involving large-scale …


Development Of Graphene Synthesis And Characterization Techniques Toward Cmos Applications And Beyond, Otto Kno Zietz Jan 2021

Development Of Graphene Synthesis And Characterization Techniques Toward Cmos Applications And Beyond, Otto Kno Zietz

Dissertations and Theses

Graphene exhibits mechanical and electrical properties which, coupled with its two dimensional (2D) morphology, make it an attractive material component for inclusion in a wide range of industries. Since the discovery of graphene in 2004, industry adoption has been limited due to the demanding synthesis requirements for high quality and connected graphene as well as the difficulties associated with direct incorporation. Chemical vapor deposition (CVD) has emerged as the most cost efficient method for producing high quality graphene at scales suitable for mass production. However, the 1000°C temperatures and micrometer thick catalysts required for this process preclude direct inclusion in …


Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman Jan 2021

Numerical Simulation Of Continuous Cone Penetration And Interpretation Of Cptu Dissipation Tests, Andrew Phillip Eugene Huffman

Dissertations and Theses

The piezocone penetration test (CPTu) is a commonly used method of geotechnical site investigation. The CPTu is especially useful because it provides a nearly continuous data profile of in-situ soil behavior, which can be correlated to useful engineering parameters. However, limitations exist for interpretation of geotechnical properties from CPTu data and for numerical analysis of cone penetration problems. The research presented in this thesis examines interpretation of coefficient of consolidation from CPTu dissipation test data and implementation of an algorithm to advance numerical simulation of cone penetration problems. This thesis presents analysis of CPTu dissipation responses from field-measured and numerically …


Best Used-Car Selling Service In Us, Sirisha Pola, Jennifer Wagner, Fenny Jin, Pallavi Gusain, Alfonso Herrero Jan 2021

Best Used-Car Selling Service In Us, Sirisha Pola, Jennifer Wagner, Fenny Jin, Pallavi Gusain, Alfonso Herrero

Engineering and Technology Management Student Projects

During the Covid-19 pandemic, a shift in the way people do things has been seen across many different industries, the automobile industry is not the exception, new car production and distribution has decreased based on the restrictions placed by many countries to ensure the safety of its citizens, this has made it quite difficult on the new car dealerships, in addition, people are seeing that the need for a car has gone down significantly since working from home has become a more and more common. However, there is a sector of the automotive industry that is having a boom, used …


Small Scale Plasma Gasification Of Municipal Solid Waste, Keith Male Jan 2021

Small Scale Plasma Gasification Of Municipal Solid Waste, Keith Male

Civil and Environmental Engineering Master's Project Reports

The goal of this project was to develop a prototype plasma gasification system to treat municipal solid waste (MSW) with minimal regulated emissions in a footprint small enough to be transported for a wide range of applicability. This project started with a review of current MSW treatment methods and of the emissions produced from thermal breakdown of MSW. A review of air quality regulations and emission control technologies was then used to select the emission control systems to be used for a small-scale plasma gasification system.

This plasma gasification system began with a plasma torch and cooling system being designed, …


High-Temperature Performance Of Ambient-Cured Alkali- Activated Binder Concrete, Kruthi Kiran Ramagiri, Darshan Chauhan, Shashank Gupta, Arkamitra Kar, Dibyendu Adak, Abhijit Mukherjee Jan 2021

High-Temperature Performance Of Ambient-Cured Alkali- Activated Binder Concrete, Kruthi Kiran Ramagiri, Darshan Chauhan, Shashank Gupta, Arkamitra Kar, Dibyendu Adak, Abhijit Mukherjee

Civil and Environmental Engineering Faculty Publications and Presentations

Owing to their lower carbon footprint and efficient performance compared to portland cement (PC), alkali-activated binders (AAB) show promising potential as an alternative to PC. The present paper investigates the high-temperature performance of AAB concrete through compressive and bond strength tests. Four different AAB concrete mixes with varying proportions of fly ash: slag (100:0, 70:30, 60:40, and 50:50) cured under ambient conditions are exposed to elevated temperatures. The mechanical performance of AAB concrete is corroborated with microstructural changes. The results show that AAB concrete with fly ash: slag ratio of 70:30 exhibits the best mechanical performance after exposure to elevated …


Spatial Accessibility And Equity Analysis Of Amazon Parcel Lockers Facilities, Jaclyn S. Schaefer, Miguel Figliozzi Jan 2021

Spatial Accessibility And Equity Analysis Of Amazon Parcel Lockers Facilities, Jaclyn S. Schaefer, Miguel Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

The onset of the COVID-19 pandemic has accelerated the growth of e-commerce and home 32 deliveries. Automated parcel lockers are a way to improve delivery efficiency, but despite their 33 rapid growth, little is known about their accessibility and equity impacts. Among e-commerce 34 players in the U.S., Amazon stands out by its large market share. This research studies the 35 location of Amazon lockers in Portland, Oregon utilizing highway, land use, employment, and 36 sociodemographic datasets. Geographical tools and cluster analysis are utilized to estimate 37 accessibility and equity metrics. Lockers tend to be located in mixed-use areas and …


On The (Im)Practicality Of Adversarial Perturbation For Image Privacy, Arezoo Rajabi, Rakesh B. Bobba, Mike Rosulek, Charles Wright, Wu-Chi Feng Jan 2021

On The (Im)Practicality Of Adversarial Perturbation For Image Privacy, Arezoo Rajabi, Rakesh B. Bobba, Mike Rosulek, Charles Wright, Wu-Chi Feng

Computer Science Faculty Publications and Presentations

Image hosting platforms are a popular way to store and share images with family members and friends. However, such platforms typically have full access to images raising privacy concerns. These concerns are further exacerbated with the advent of Convolutional Neural Networks (CNNs) that can be trained on available images to automatically detect and recognize faces with high accuracy.

Recently, adversarial perturbations have been proposed as a potential defense against automated recognition and classification of images by CNNs. In this paper, we explore the practicality of adversarial perturbation based approaches as a privacy defense against automated face recognition. Specifically, we first …


'Menthol-Plus’: A Major Category Of Cigarette Found Among ‘Concept’ Descriptor Cigarettes From Mexico, James F. Pankow, Wentai Luo, Kevin J. Mcwhirter, Samantha M. Gillette, Joanna E. Cohen Jan 2021

'Menthol-Plus’: A Major Category Of Cigarette Found Among ‘Concept’ Descriptor Cigarettes From Mexico, James F. Pankow, Wentai Luo, Kevin J. Mcwhirter, Samantha M. Gillette, Joanna E. Cohen

Civil and Environmental Engineering Faculty Publications and Presentations

Background Tobacco companies are offering cigarettes with ‘concept’ descriptor names that suggest sensation and/or flavour properties (eg, Marlboro ‘Velvet Fusion’). Little has been known about the identities and levels of flavour chemicals in such cigarettes.

Methods Thirty-three filter cigarette variants from 27 packs (including two sampler packs with four variations each) from Canada and Mexico were analysed (rod + filter) for 177 flavour chemicals plus triacetin, a filter plasticiser and possible flavourant. Five brands of US mentholated filter cigarettes were also analysed.

Results Twenty-seven of the 33 cigarettes (all were Mexican variants) were categorised as ‘menthol-plus’: significant menthol (3.0–11.9 mg/cigarette), …


Exploring The Impact Of Socio-Demographic Characteristics, Health Concerns, And Product Type On Home Delivery Rates And Expenditures During A Strict Covid-19 Lockdown Period: A Case Study From Portland, Or, Miguel Figliozzi, Avinash Unnikrishnan Jan 2021

Exploring The Impact Of Socio-Demographic Characteristics, Health Concerns, And Product Type On Home Delivery Rates And Expenditures During A Strict Covid-19 Lockdown Period: A Case Study From Portland, Or, Miguel Figliozzi, Avinash Unnikrishnan

Civil and Environmental Engineering Faculty Publications and Presentations

E-commerce volumes and home deliveries have experienced steady growth in the last two decades. Strict COVID-19 lockdowns made home delivery an essential service and a lifeline for many households that, for travel restrictions or health concerns, were not able to utilize traditional shopping methods. This research studies the impact of socio-demographic variables and e-commerce attitudes on household deliveries for seven product categories (groceries, meals, electronics, household and office goods, recreational items, and fashion, beauty and personal care products, and medicine/health-related products) during the lockdown period in the greater Portland metropolitan region. To understand these impacts, exploratory factor analysis and …