Engineering Commons^™

A Pipeline For Enhanced Multimodal 2d Imaging Of Concrete Structures, Sina Mehdinia, Thomas Schumacher, Xubo Song, Eric A. Wan

Civil and Environmental Engineering Faculty Publications and Presentations

We present an imaging pipeline to achieve enhanced images of the interior of concrete from ground penetrating radar (GPR) and ultrasonic echo array (UEA) measurements. This work lays the foundation for an advanced yet practical imaging tool to assess concrete structures. Specifically, we propose an enhanced two-dimensional (2D) total focusing method (XTFM) to reconstruct images from raw GPR and UEA data. The proposed XTFM algorithm integrates total focusing method (TFM) and synthetic aperture focusing technique (SAFT) concepts to post-process large independent and interelement measurements from both modalities in a computationally efficient way. Furthermore, we introduce a novel 2D image fusion …

The Ejection Of Large Non-Oscillating Droplets From A Hydrophobic Wedge In Microgravity, Logan Torres, Mark M. Weislogel

Mechanical and Materials Engineering Faculty Publications and Presentations

When confined within containers or conduits, drops and bubbles migrate to regions of minimum energy by the combined effects of surface tension, surface wetting, system geometry, and initial conditions. Such capillary phenomena are exploited for passive phase separation operations in micro-fluidic devices on earth and macro-fluidic devices aboard spacecraft. Our study focuses on the migration and ejection of large inertial-capillary drops confined between tilted planar hydrophobic substrates (a.k.a., wedges). In our experiments, the brief nearly weightless environment of a 2.1 s drop tower allows for the study of such capillary dominated behavior for up to 10 mL water drops with …

Forecasting Technology Trends Through The Gap Between Science And Technology: The Ase Of Software As An E-Commerce Service, Tugrul Daim, Esraa Bukhari, Dana Bakry, James Vanhuis, Haydar Yalcin, Xiaoli Wang

Engineering and Technology Management Faculty Publications and Presentations

Identifying technology trends can be a key success factor for companies to be competitive and take advantage of technological trends before they occur. The companies always work to plan for future products and services. For that, it is important to turn to methods that are used for technology forecasting. These tools help the companies to define potential markets for innovative new products and services. This paper uses text mining techniques along with expert judgment to detect and analyze the near-term technology evolution trends in a Software as a Service (SaaS) case study. The longer-term technology development trend in this case …

Microstructure And Mechanical Properties Of Cast And Hot-Rolled Medium-Carbon Steels Under Isothermal Heat-Treatment Conditions, Byungsue Shin, Kwangyuk Kim, Sung Yi, Sanggyu Choi, Soongkeun Hyun

Mechanical and Materials Engineering Faculty Publications and Presentations

In this study, the changes in the microstructure and mechanical properties during isothermal heat treatment of cast steel before and after hot deformation were investigated using medium carbon steel with low alloy content. The microstructural characteristics of the cast and hot-rolled medium-carbon steel under isothermal heat-treatment conditions were examined using optical microscopy and scanning electron microscopy in conjunction with electron backscatter diffraction. The variation in the mechanical properties was evaluated using Rockwell hardness and tensile tests. After maintaining an austenitizing condition at 1200 ◦C for 30 min, an isothermal heat treatment was performed in the range 350–500 ◦C, followed by …

Characterization Of Coupling Between Inertial Particles And Turbulent Wakes From Porous Disk Generators, Kristin N. Travis, Sarah E. Smith, Laure Vignal, Henda Djeridi, Mickael Bourgoin, Raul Bayoan Cal, Martin Obligado

Mechanical and Materials Engineering Faculty Publications and Presentations

This study presents the findings of a wind tunnel experiment investigating the behaviour of micrometric inertial particles with Stokes numbers around unity in the turbulent wake of a stationary porous disk. Various concentrations Φv ∈ ([6 − 19] × 10−6) of poly-disperse water droplets (average diameter 40–50μm) are compared with sub-inertial tracer particles. Hot-wire anemometry, phase Doppler interferometry and particle image velocimetry were implemented in the near- and far-wake regions to study the complex dynamics of such particles. Quadrant analysis is used to explore the shear effects of the particle wake interaction. Turbulence statistics and particle size distributions reveal distinct …

Dual Multivector Model Predictive Control For The Power Converters Of A Floating Owc Wec, Marcos Blanco, Dionisio Ramirez, Mohammad Ebrahim Zarei, Mahima Gupta

Electrical and Computer Engineering Faculty Publications and Presentations

Oscillating Water Column (OWC) is one of the most well-known wave energy converter (WEC). Typically, OWCs are installed in rocky shores or in custom-built breakwaters. However, since the wave profile is more favorable in an open sea, it can also be installed in a point absorber in order to increase the energy extraction.

This paper presents the development of a new dual Multivector Model Predictive Control (MMPC) for the power converters of a floating OWC WEC. The fast dynamic response featured by the proposed MMPC has proven to be very suitable to deal with the highly variable torque and velocity …

The Draining Of Capillary Liquids From Containers With Interior Corners Aboard The Iss, Joshua Thomas Mccraney, Mark M. Weislogel, Paul Steen

Mechanical and Materials Engineering Faculty Publications and Presentations

In this work, we analyze liquid drains from containers in effective zero-g conditions aboard the International Space Station (ISS). The efficient draining of capillary fluids from conduits, containers, and media is critical in particular to high-value liquid samples such as minuscule biofluidics processing on earth and enormous cryogenic fuels management aboard spacecraft. The amount and rate of liquid drained can be of key concern. In the absence of strong gravitational effects, system geometry, and liquid wetting dominate capillary fluidic behavior. During the years 2010–2015, NASA conducted a series of handheld experiments aboard the ISS to observe “large” length scale capillary …

Novel Quantum Algorithms To Minimize Switching Functions Based On Graph Partitions, Peng Gao, Marek A. Perkowski, Yiwei Li, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

After Google reported its realization of quantum supremacy, Solving the classical problems with quantum computing is becoming a valuable research topic. Switching function minimization is an important problem in Electronic Design Automation (EDA) and logic synthesis, most of the solutions are based on heuristic algorithms with a classical computer, it is a good practice to solve this problem with a quantum processer. In this paper, we introduce a new hybrid classic quantum algorithm using Grover’s algorithm and symmetric functions to minimize small Disjoint Sum of Product (DSOP) and Sum of Product (SOP) for Boolean switching functions. Our method is based …

Effectiveness Assessment Of The Search-Based Statistical Structural Testing, Yang Shi, Xiaoyu Song, Marek A. Perkowski, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

Search-based statistical structural testing (SBSST) is a promising technique that uses automated search to construct input distributions for statistical structural testing. It has been proved that a simple search algorithm, for example, the hill-climber is able to optimize an input distribution. However, due to the noisy fitness estimation of the minimum triggering probability among all cover elements (Tri-Low-Bound), the existing approach does not show a satisfactory efficiency. Constructing input distributions to satisfy the Tri-Low-Bound criterion requires an extensive computation time. Tri-Low-Bound is considered a strong criterion, and it is demonstrated to sustain a high fault-detecting ability. This article tries to …

Concolic Execution Of Nmap Scripts For Honeyfarm Generation, Zhe Li, Bo Chen, Wu-Chang Feng, Fei Xie

Computer Science Faculty Publications and Presentations

Attackers rely upon a vast array of tools for automating attacksagainst vulnerable servers and services. It is often the case thatwhen vulnerabilities are disclosed, scripts for detecting and exploit-ing them in tools such asNmapandMetasploitare released soonafter, leading to the immediate identification and compromise ofvulnerable systems. Honeypots, honeynets, tarpits, and other decep-tive techniques can be used to slow attackers down, however, such approaches have difficulty keeping up with the sheer number of vulnerabilities being discovered and attacking scripts that are being released. To address this issue, this paper describes an approach for applying concolic execution on attacking scripts in Nmap in …

An Adjustable Stiffness Torsional Magnetic Spring With A Linear Stroke Length, Dawei Che, Jonathan Z. Bird, Alex Hagmüller, Md Emrad Hossain

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents the analysis, mechanical design, and proof-of-principle experimental testing of a new type of adjustable stiffness torsional magnetic spring for an ocean generator application. Unlike prior published designs the rotary magnetic spring is shown to have a highly linear adjustable stroke length. The presented torsional spring is experimentally shown to be able to create a ± 45° angular stroke range with a peak torque of ± 39.1 N·m. The stiffness is adjusted by using a stepper motor to axially adjust the axial magnet offset. The stepper motor contains a brake so that power is not expended when maintaining …

High-Entropy Alloys Properties Prediction Model By Using Artificial Neural Network Algorithm, Sanggyu Choi, Sung Yi, Junghan Kim, Byungsue Shin, Soongkeun Hyun

Mechanical and Materials Engineering Faculty Publications and Presentations

A new approach method has been studied for the efficient and accurate prediction of high-entropy alloys (HEAs) properties. The artificial neural network (ANN) algorithm was employed to predict the mechanical properties such as yield strength, microstructure, and elongation of the alloy by training from the mole fraction and post-process information that has an influence on the mechanical properties. The mean error rate of prediction for the yield strength was 19.6%. Microstructure predictions were consistent for all test data. On the other hand, the ANN model trained only with mole fraction data had a yield strength prediction error of 33.9%. Omission …

Fourth-Order Nonlinear Distortion To The Power Spectrum Of Rf Amplifiers, Xianzhen Yang, Shiyu Li, Fu Li

Electrical and Computer Engineering Faculty Publications and Presentations

Even-order intermodulation distortions are often considered easy to filter in narrowband radio frequency (RF) wireless systems because they are usually located far away from the desired passband and adjacent bands. However, even-order intermodulation distortions have recently attracted more interest with the increasing popularity of wideband RF appli- cations. The authors’ previous work was devoted to establishing the power spectrum model of second-order intermodulation distortion. Motivated by the latest efforts on RF power amplifier linearization with second-order and fourth-order intermodulation, our focus now is to establish a power spectrum model of fourth-order intermodulation distortion which can be used to discuss the …

Model Optimization For Resource Allocation In A Consulting Firm, Riad Alharithi, Karthik Manjunath, Sara Ferdousi, Vladislav Ruchin, Jennifer Lynn Zeitouni

Engineering and Technology Management Student Projects

Assigning employees with multiple skill sets to projects at the right time has long been a challenge in professional settings. Whether it is assigning a salesperson to a product, an employee to a task, or a company to a project, many variables affect such decisions and make them taxing for managers and owners. In this project, an optimization issue observed in a team member’s workplace is being addressed.. The aim is to efficiently allocate employees to different concurrent projects. The firm's organizational structure is similar to a Project Management Office (PMO) that has an employee pool with varying skill sets …

Autonomous Farming With Uavs, Pallavi Agrawal, Karthik Manjunath, Cherokee Rawls, Sujitha Raj Rajagopal, Riad Alharithi, Kamal Thapa

Engineering and Technology Management Student Projects

As the global need for food grows, agriculture is adapting autonomous farming techniques to scale in response. One of the most useful tools are UAVs (Unmanned Autonomous Vehicles), which are providing invaluable information and assistance to farmers. In some countries, UAVs are being rapidly embraced, while in others this progress is much slower. For a number of reasons, the United States has not broadly adopted this technology in assisting agricultural practices. In this article, we focus on the challenges companies and farmers are facing in making use of UAVs and what might be done to push this technology into widespread …

Tourism Route Optimization For Portland, Oregon, Duane Murray, Mohammed Thawab, Adnan Binmahfood, Mohammed Zaid, Colin Owens

Engineering and Technology Management Student Projects

The city of Portland, Oregon has experienced an unprecedented reduction in tourism due to the COVID-19 pandemic. This reduction in tourism has had a negative impact on all businesses in the area. This paper provides a methodology and tool that can be used to help local businesses potentially gain patrons, and at the same time help visitors in maximizing their time while minimizing costs. when visiting the city after the pandemic abates. To accomplish this, first, an itinerary of selected attractions are filtered by the visitor. Next, a linear programming method using a travelling salesman problem (TSP) algorithm is implemented …

Deep Learning Approach For Screening Autism Spectrum Disorder In Children With Facial Images And Analysis Of Ethnoracial Factors In Model Development And Application, Angelina Lu, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

Autism spectrum disorder (ASD) is a developmental disability that can cause significant social, communication, and behavioral challenges. Early intervention for children with ASD can help to improve their intellectual ability and reduces autistic symptoms. Multiple clinical researches have suggested that facial phenotypic differences exist between ASD children and typically developing (TD) children. In this research, we propose a practical ASD screening solution using facial images through applying VGG16 transfer learning-based deep learning to a unique ASD dataset of clinically diagnosed children that we collected. Our model produced a 95% classification accuracy and 0.95 F1-score. The only other reported study using …

An Automated Ar-Based Annotation Tool For Indoor Navigation For Visually Impaired People, Pei Du, Nirupama Bulusu

Computer Science Faculty Publications and Presentations

Low vision people face many daily encumbrances. Traditional visual enhancements do not suffice to navigate indoor environments, or recognize objects efficiently. In this paper, we explore how Augmented Reality (AR) can be leveraged to design mobile applications to improve visual experience and unburden low vision persons. Specifically, we propose a novel automated AR-based annotation tool for detecting and labeling salient objects for assisted indoor navigation applications like NearbyExplorer. NearbyExplorer, which issues audio descriptions of nearby objects to the users, relies on a database populated by large teams of volunteers and map-a-thons to manually annotate salient objects in the environment like …

Proximal Policy Optimization For Radiation Source Search, Philippe Erol Proctor, Christof Teuscher, Adam A. Hecht, Marek Osiński

Electrical and Computer Engineering Faculty Publications and Presentations

Rapid search and localization for nuclear sources can be an important aspect in preventing human harm from illicit material in dirty bombs or from contamination. In the case of a single mobile radiation detector, there are numerous challenges to overcome such as weak source intensity, multiple sources, background radiation, and the presence of obstructions, i.e., a non-convex environment. In this work, we investigate the sequential decision making capability of deep reinforcement learning in the nuclear source search context. A novel neural network architecture (RAD-A2C) based on the advantage actor critic (A2C) framework and a particle filter gated recurrent unit for …

Head-Wave Correlations In Layered Seabed: Theory And Modeling, Jie Li, Martin Siderius, Peter Gerstoft, Jun Fan, Lanfranco Muzi

Electrical and Computer Engineering Faculty Publications and Presentations

This paper derives travel times and arrival angles of head-wave correlations from ocean ambient noise in shallow water over a layered seabed. The upcoming and surface reflected head-wave noise signal received at two receivers from the same interface are correlated, and their travel time differences give the travel times of the head-wave correlations. The arrival angle of head-wave correlations from an interface depends on sound speeds in the layers above and just below. The predictions of head-wave correlations from a seabed with two layers and the corresponding inversion results are verified with simulations.

A 3d Crossbar Architecture For Both Pipeline And Parallel Computations, John M. Acken, Muayad J. Aljafar

Electrical and Computer Engineering Faculty Publications and Presentations

A 3D architecture made up of a CMOS layer combined with a 3D stack of bipolar memristor crossbar arrays provides an innovative approach to hardware support for utilizing the strength of CMOS combined with the strength of memristors. Memristors have been evaluated for implementing a broad spectrum of applications such as memory, computations, hardware-based security primitives, cryptography, etc., and numerous studies have shown that memristors are desirable candidates for such applications. This paper proposes a novel 3D memristive crossbar architecture (i.e., a stack of memristive crossbar arrays built on top of CMOS substrate) with a specific focus on the way …

Deep Learning-Based Penetration Depth Prediction In Al/Cu Laser Welding Using Spectrometer Signal And Ccd Image, Sanghoon Kang, Minjung Kang, Yong Hoon Jang, Cheolhee Kim

Mechanical and Materials Engineering Faculty Publications and Presentations

In the laser welding of thin Al/Cu sheets, proper penetration depth and wide interface bead width ensure stable joint strength and low electrical conductance. In this study, we proposed deep learning models to predict the penetration depth. The inputs for the prediction models were 500 Hz-sampled low-cost charge-coupled device (CCD) camera images and 100 Hz-sampled spectral signals. The output was the penetration depth estimated from the keyhole depth measured coaxially using optical coherence tomography. A unisensor model using a CCD image and a multisensor model using a CCD image and the spectrometer signal were proposed in this study. The input …

What’S Left Before Participatory Modeling Can Fully Support Real-World Environmental Planning Processes: A Case Study Review, Beatrice Hedelin, S. Gray, S. Woehlke, Todd K. Bendor, Alison Singer, R. Jordan, Moira Zellner, Philippe J. Giabbanelli, Pierre D. Glynn, Antoine J. Jetter, Multiple Additional Authors

Engineering and Technology Management Faculty Publications and Presentations

In environmental participatory modeling (PM), both computer and non-computer-based modeling techniques are used to aid participatory problem description, solution, and decision-making actions in environmental contexts. Although many PM case studies have been published, few efforts have sought to systematically describe and understand dominant PM processes or establish best practices for PM. As a first step, we have reviewed a random sample of environmental PM case study articles (n = 60) using a novel PM process evaluation instrument. We found that significant work likely remains for PM to fully support participatory and integrated planning processes. While PM reports systematically address knowledge …

Exploring How Antecedent Precipitation Amount And The Effects Of Covid-19 Affect Stormwater Runoff Quality Along Urban Gradients, Daniel Ramirez, Katherine Gelsey

REU Final Reports

Stormwater runoff quality is affected by a multitude of factors including surrounding land characteristics, human activities, and antecedent precipitation amounts. We explore how seasonal and variable precipitation affect E. Coli, total suspended solids, nitrogen-nitrate, orthophosphate, lead, and zinc concentrations in Portland, OR, USA. Correlation analysis was conducted between the pollutant concentrations and antecedent rainfall each sample site received for the previous 1, 3, 5, 7, and 30 days from when the sample was taken. We ran Mann-Whitney tests to determine if the levels of the pollutants were statistically different between the wet season and the dry season. We found that …

Modeling Renal Function During Pregnancy, Christina A. Valtierra

REU Final Reports

The main goal of this research project is to build a computational model that illustrates the main processes in renal function during pregnancy. The analysis of how pregnancy affects all the factors that take place within the kidney will allow for a better understanding of how pathologies like proteinuria, hypertension, and glomerular endotheliosis develop. This model is a small part of a more complex model that showcases the complete pathophysiology of preeclampsia.

E-Scooter Safety And How To Improve It, Eric Valentino

altREU Projects

In the last few years, electronic scooters have taken over cities as a means of personal transportation. Between 2017 and 2019 alone, over 30 million trips were recorded across over 100 cities in the US. These scooters pose a safety risk, as 20 in 100,000 trips will result in injury of the rider. On top of this, scooters can cause damage to property, injury pedestrians and motor vehicle drivers, as well as obstruct important infrastructure such as wheelchair ramps. For these reasons, it is important to develop an understanding of the factors that contribute to e-scooter related injuries in order …

Modeling The Effect Of The Covid-19 Pandemic On Azithromycin Prescription In General Practices Across The Uk, Oluwasegun Isaac Daramola

altREU Projects

In the early months of the COVID-19 pandemic, it was reported that some antibiotics were prescribed as a remedy for viral treatment and prophylaxis based on non-randomized, uncontrolled short clinical trials. A major antibiotic consulted being Azithromycin; a broad-spectrum macrolide selected based on its immunomodulatory effects in chronic inflammatory lung diseases, with a seasonal prescription increase of 21.5% in March 2020 compared to March 2019.

To analyze the effect and possible antimicrobial resistance impact of the pandemic on Azithromycin prescription across general practices in the United Kingdom (UK), this study uses a time series decomposition modeling method to compare a …

Developing A Strategy For Creating Affordable Student Housing Solutions, Juan D. Campolargo

altREU Projects

College is becoming more and more expensive, and students are graduating with more and more debt. In 2021, we have almost 1.6 trillion dollars of student loan debt. While students are in college, they need a place to live, and this project will be about how to develop a strategy for creating affordable student housing solutions.

Housing should not be another cause of concern to students or really anyone.

The way it’s done is that people get more loans to pay for housing, or they work as much as they can when they’re not studying to pay for rent. Affordable …

Digitally Reporting Trail Obstructions In Forest Park, Colton S. Maybee

REU Final Reports

The inclusion of technology on the trail can lead to better experiences for everyone involved in the hobby. Hikers can play a more prominent role in the maintenance of the trails by being able to provide better reports of obstructions while directly on the trail. This paper goes into the project of revamping the obstruction report system applied at Forest Park in Portland, Oregon. Most of my contributions to the project focus on mobile app development with some research into path planning algorithms related to the continuations of this project.

Agent-Based Activity Generation Of Runners For City Infrastructure Planning, Quang Le

REU Final Reports

Since the pandemic started, many gyms and indoor classes have been shut down to mitigate the spread of Coronavirus. Many people have been forced to get onto pavement streets to get some fresh air while running around and coping with the new reality. There are over 60 million runners in the U.S., and that number is growing rapidly during this time without any sign of stopping once life gets back to normal. In this project, an agent-based model has been developed to generate a set of routes that runners would take in their daily run in a neighborhood of Portland …