Engineering Commons^™

Evaluation Of A Novel Remote Displacement Sensor Prototype Using Video And Laser-Based Technology For Civil Infrastructure Applications, Nicholas J. Brown

Civil and Environmental Engineering Master's Project Reports

Deflection measurements on structures, especially with regards to long-term monitoring, continues to be a challenge with current sensor technologies. Material degradation and changes in the mechanical properties due to aging (for example, creep and shrinkage in concrete bridges) directly impact the deflections exhibited by a structure. In this article we introduce and discuss the evaluation of a novel laser and video-based displacement sensor prototype to monitor displacements and rotations in structures remotely. The sensor is both inexpensive, using off-the shelf components, but also accurate and practical for situations that do not allow the use of conventional displacement sensors, which require …

Flood Dynamics In The Portland Metropolitan Area, Past, Present, And Future, Lumas Terence Helaire

Dissertations and Theses

The Portland area has an extensive flood history since it was founded in 1845. In the late 19th century, the Portland area was prone to flooding from snowmelt freshets (3-6 months duration) and brief winter rain or rain-on-snow events. Since that time the magnitude of spring freshets has been curtailed by 45% due to climate change, flow diversions, and reservoir management. Along with changes in hydrology, the bathymetry of the Lower Columbia River has been altered by the dredging of the navigation channel, diking, and land reclamation. To understand how these changes in hydrology and bathymetry have affected tidal and …

An Application Of Deep Learning Models To Automate Food Waste Classification, Alejandro Zachary Espinoza

Dissertations and Theses

Food wastage is a problem that affects all demographics and regions of the world. Each year, approximately one-third of food produced for human consumption is thrown away. In an effort to track and reduce food waste in the commercial sector, some companies utilize third party devices which collect data to analyze individual contributions to the global problem. These devices track the type of food wasted (such as vegetables, fruit, boneless chicken, pasta) along with the weight. Some devices also allow the user to leave the food in a kitchen container while it is weighed, so the container weight must also …

The Optimized Synthesis Of Copper Nanowire For High-Quality And Fabrication Of Core-Shell Nanowire, Suhyun Lee

Dissertations and Theses

Flexible electronics are the promising technology for prospective application in foldable phones. Currently, indium tin oxide (ITO) has been widely used for electronic devices including flat-panel display. However, it is brittle and expensive. Metal nanowires are considered as alternative materials. Among various metal nanowires, copper nanowires are attractive because of its high electrical conductivity, better flexibility, and low cost compared with ITO. However, copper nanowires are very prone to oxidize, which causes subsequent degradation of electrical conductivity. Due to this oxidation issue, core-shell structure nanowires, which are formed silver shell having high conductivity and low resistivity on the surfaces of …

Hf Iq Mixer Vfo Temperature Compensation And Drive Level Optimization For Opposite Sideband Suppression, Katlin Anne-Rostomyan Dahn

Dissertations and Theses

An amateur radio 40m band temperature compensated variable frequency oscillator (VFO) with drive-level optimized for opposite sideband suppression for use as the local oscillator (LO) of a high frequency (HF) IQ image reject mixer is considered in this work. The first problem of this thesis was the discovery of the HF IQ mixer's opposite sideband suppression dependence on LO drive-level. As a solution to this problem, the author built a fixed drive-level VFO for the optimal opposite sideband suppression. This then led to the second problem of this thesis; the discovery by this author of the well-known problem of VFO …

Passive Separation Of Binary Fluid Mixtures In Microchannels Using Lattice Boltzmann Method, Mohanad Kamil Radhi

Dissertations and Theses

Fluid mixtures in real life exist in two forms: miscible and immiscible. Separation of these mixtures using chemical agents or thermal energy has both environmental and economic disadvantages. The high cost and the environmental damage caused by the traditional separation techniques have stimulated both academia and industry to seek alternatives. The emergence of microfluidics offers robust solutions for a broad span of transport problems due to the high surface to volume ratio and reduced length scales. Particularly, the separation efficiency increases significantly due to the aforementioned feature. However, there is still a pressing need of passive separations for the sake …

Optimizing On-Street Parking Supply With Analytical Models, Chawalit Tipagornwong

Dissertations and Theses

Commercial vehicles are crucial for the urban economy, but they generate negative impacts as well. This leads to restrictions such as a reduction in the number of loading zones. The result is that commercial drivers spend a significant amount of time searching for available loading zones. To avoid searching for parking, some commercial drivers double park, which causes traffic congestion. Therefore, the number of loading zones should be set properly. Since a curb is allocated between both loading zones and parking spaces, both parking types have to be considered. Many on-street parking management strategies have been implemented, including pricing meter …

Impact Of Titanium Dioxide Nanoparticles On Nutrient And Contaminant Reduction In Wastewater Treatment Wetlands, Madeline Hubbard

Civil and Environmental Engineering Master's Project Reports

Metallic nanoparticles are found in a variety of commercial products and industrial processes, and have become more common in the last few decades. As nanoparticles are toxic to biota and have the potential to spread other types of contamination, their increased use has become a concern. Research into the transport of nanoparticles in subsurface and surface waters shows a wide range in mobility, but that they are most likely to collect in systems with low linear velocities and high organic content. As a result, wetlands are the most vulnerable to nanoparticle contamination. Wetlands receiving and treating wastewater effluent have an …

Audio Beat Detection With Application To Robot Drumming, Michael James Engstrom

Dissertations and Theses

This Drumming Robot thesis demonstrates the design of a robot which can play drums in rhythm to an external audio source. The audio source can be either a pre-recorded .wav file or a live sample .wav file from a microphone. The dominant beats-per-minute (BPM) of the audio would be extracted and the robot would drum in time to the BPM. A Fourier Analysis-based BPM detection algorithm, developed by Eric Scheirer (Tempo and beat analysis of acoustical musical signals)ⁱ was adopted and implemented. In contrast to other popular algorithms, the main advantage of Scheirer's algorithm is it has …

Modeling And Control Of Magnetic Gear Dynamics In A Wind Turbine Drivetrain, Danielle Vournas

Dissertations and Theses

This thesis looks at the modeling and simulation of linear and nonlinear magnetic gear dynamics in a wind turbine drivetrain. The objective is to lay the groundwork for analysis, modeling and optimization of control structures focused on pole-slip prevention. A classical mechanical two-mass torsion spring model is used as the basis for developing the dynamic system equations and Simulink models. The wind turbine torque input to the low speed rotor is modeled as a disturbance input, the generator torque is modeled as a controlled input, and the high-speed rotor speed is the only measured output. The nonlinear dynamics are linearized; …

Tracking Center Of Mass With Limited Inertial Measurement Units, Connor Nathaniel Morrow

Dissertations and Theses

Wearable motion tracking systems pose an opportunity to study and correct human balance and posture during movement. Currently, these observations are either being conducted in laboratories with the use of camera systems and markers placed on the body, or through the use of suits containing large numbers (15-20) of inertial measurement units. However, to aid with rehabilitation of individuals with impaired balance, there needs to be an option to collect these observations outside of clinics and without incurring much cost from the user. I have focused on three inertial measurement units, one placed on each shank and one placed on …

Concrete Bridge Deck Performance Data And Metrics For The State Of Oregon, Jael Wettach-Glosser

Dissertations and Theses

Bridge decks are a critical element of a bridge that support and distribute vehicle loads to the superstructure. Because of the requirements of this role, bridge decks are exposed to severe conditions that typically lead to structural deficiency in bridges which is both costly and disruptive. Therefore, to keep bridges and highways in good repair, developing optimal preservation decisions for concrete bridge decks is key. In order to develop effective performance monitoring and preservation schedules, the parameters affecting bridge deck deterioration need to be better understood.

With guidance from the literature and Oregon Department of Transportation (ODOT) personnel, two datasets …

Non-Contact Distillation, Rawand Muzafar Rasheed

Dissertations and Theses

Leidenfrost phenomenon has been studied extensively for its role in applications ranging from nuclear reactor cooling, to metals manufacturing, combustion, and other fields. Herein, Leidenfrost phenomenon is pursued towards non-contact distillation processes with hopes of reducing or even eliminating contaminant fouling. In particular, the microgravity environment of a drop tower is exploited to demonstrate the facility with which droplets achieve and sustain the Leidenfrost state. Dynamic Leidenfrost impacts in microgravity are presented for impacts on hydrophilic and superhydrophobic planar substrates, macro-pillar arrays, confined passageways, and others. Nearly ideal elastic non-contact impacts and droplet oscillation modes are observed. Dynamic Leidenfrost impacts …

Water Quality Analysis Of Ecoroof Runoff In Portland, Pranoti P. Deshmukh

Civil and Environmental Engineering Master's Project Reports

Portland, Oregon is internationally recognized for its implementation of sustainable stormwater management technologies. Ecoroof is one of the sustainable solutions to reduce stormwater runoff which also provides multiple environmental benefits. However, very little is known about the impact of ecoroofs on water quality of roof runoff. Stormwater runoff carries a significant amount of pollutants, which, if it directly enters a stream or river, degrades water quality and severely harms aquatic life.

This study evaluates the trends in the long-term water quality data from ecoroofs and conventional roofs in the Portland area. Mann Kendall trend test was used to detect the …

Modeling Vertical Migration Of Cyanobacteria And Zooplankton, Corina Christina Mae Overman

Dissertations and Theses

Cyanobacteria, also known as blue-green algae, often cause harmful algal blooms and release toxic substances that can harm humans and other animals. Accurately modeling these phytoplankton is a step towards predicting, preventing, and controlling such blooms. Cyanobacteria and zooplankton species are known to migrate vertically in the water column on a daily cycle. Capturing this behavior is one aspect of correctly modeling their dynamics. Here, several models of cyanobacteria vertical movement were tested in proof-of-concept models before being applied to data from field studies. These models included both continuum and particle-tracking frameworks. Four continuum-framework models of cyanobacteria vertical migration were …

Evaluation Of Low And High Frequency Dynamic Response For Condition Assessment Of Reinforced Concrete Structures, Ali Hafiz

Dissertations and Theses

Concrete is widely used for civil infrastructure structures and they experience deterioration and degradation due to aging, increases in the traffic loads, harsher environmental conditions, use of deicing chemicals, etc. Therefore, evaluating the integrity of reinforced concrete structures has become of increasing interest for infrastructure owners and managers. A number of non-destructive testing (NDT) and structural health monitoring (SHM) methods have been developed in recent decades to aid in evaluating structures and provide input for asset management. One family of these methods uses the dynamic response of a structural member: stress waves (high frequency) and structural vibrations (low frequency). Both …

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 …

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 …

Large-Scale Der Aggregations Of Electric Water Heaters And Battery Inverter Systems, Kevin Marnell

Dissertations and Theses

Distributed energy resources like residential electric water heaters and residential battery inverter systems offer a small amount of change to the grid individually. When aggregated however, these assets can cause major effects to the electric grid. Aggregating these resources allows them to take on generator-like functions with the ability to increment power and decrement power.

The Western Energy Imbalance Market is an energy market offering 15 minute and 5 minute markets for energy transactions between balancing areas. Generation assets make increment and decrement bids. Traditionally the only entrants to this market have been large scale generators and large scale assets …

Travel Behaviors Of Persons With Intellectual And Developmental Disabilities, Joseph C. Totten

Civil and Environmental Engineering Master's Project Reports

People with intellectual and developmental disabilities live different lives than the general population. Often prohibited from driving, persons with intellectual disabilities cite transportation as top concern, limiting their independence and freedom to live, work or recreate where and when they choose. Improving services for persons with developmental disabilities requires that engineers and planners understand how persons with intellectual disabilities travel, and what types of transportation are available to them. This report hopes to identify the availability of transportation options to persons with developmental disabilities such that planners, engineers and advocates can determine how altering the transportation system might affect persons’ …

Test Setup Design And Cyclic Evaluation Of Rocking Clt Wall And Floor Restoring Force Lateral System, Aaron Davis Smith

Civil and Environmental Engineering Master's Project Reports

The introduction of the demand for mass timber buildings in areas with seismic hazards has called for new lateral systems. Lateral systems in mass timber building typically utilize a rocking shear wall with post-tensioned rods to provide system re-centering. These post-tensioned rods add axial load to the shear wall and potentially endure long term creep affects. Mass Timber buildings consist of cross laminated (clt) shear walls and floor slabs along with glulam beams. The flexural capacity of the CLT floor slabs along with dead load can provide an alternative source for the restoring force. This project developed a test setup …

The Gouda, The Bad, And The Ugly: Prioritizing Intersections For Pedestrian Safety In Tillamook, Or With Different Risk Estimation Methods, Kelly M. White

Civil and Environmental Engineering Master's Project Reports

The following report explores five different pedestrian risk estimation methods at urban intersections. Six study intersections in Tillamook, Oregon were chosen as a case study to analyze each risk estimation method and apply the values to a project prioritization process. Ultimately, risk factors of both exposure and infrastructure contribute to the highest amount of risk for pedestrians. The Oregon Department of Transportation's State Planning and Research Report 779 was identified as the most comprehensive risk estimation method.

Characterizing Tilt Effects On Wind Plants, Ryan Scott

Dissertations and Theses

Tilting the nacelle of a wind turbine modifies entrainment into the wind plant and impacts total efficiency. Extreme angles can produce flying and crashing wakes where the wake either disrupts entertainment from the undisturbed flow above or is decimated on the ground. The effect of tilt angle on downstream wake behavior was investigated in a series of wind tunnel experiments. Scale model turbines with a hub height and diameter of 12 cm were arranged in a Cartesian array comprised of four rows of three turbines each. Nacelle tilt was varied in the third row from -15° to 15° in chosen …

Infinite Photovoltaic Solar Arrays: Considering Flux Of Momentum And Heat Transfer, Andrew D. S. Glick

Dissertations and Theses

Large scale solar farms supply an increasing amount of the worlds electricity supply. However, in order to reach cost parity with fossil fuels, further reductions are necessary. Towards this end, photovoltaic (PV) panel cooling becomes increasingly important; high temperatures both decrease efficiency and panel lifetime. To better understand, characterize, and exploit the natural convective cooling of utility scale solar farms, a model solar farm was created. Using both thermal measurements and particle image velocimetry to characterize heat transfer and velocity fields, wind tunnel experiments were conducted using the model solar farm. Three parameters were examined for their effect on heat …

Aggregation Of Electric Water Heaters For Peak Shifting And Frequency Response Services, Thomas Leighton Clarke

Dissertations and Theses

The increased penetration of renewable energy sources poses new challenges for grid stability. The stochastic and uncontrollable generation of solar and wind power cannot be adjusted to match the load profile, and the transition away from traditional synchronous generators is reducing the grid capacity to arrest and recover from frequency disturbances.

Additionally, the distributed nature of many renewable energy sources makes centralized control of generation more complicated. The traditional power system paradigm balances the supply and demand of electricity on the grid by regulating generation. As this becomes more difficult, one alternative is to adjust the load instead. This is …

Physics-Based Signal Processing Methods For Terahertz Non-Destructive Evaluation Of Layered Media, Scott G. Schecklman

Dissertations and Theses

In recent years Terahertz (THz) time domain spectroscopy has emerged as a promising new technology with potential applications in a variety of fields, including industrial manufacturing, security screening and medical imaging. Pulsed THz systems are uniquely suited for non-destructive evaluation (NDE) of the sub-surface layers of dielectric packaging and coating materials, because they provide high dynamic range over a wide bandwidth in the far infrared portion of the electromagnetic spectrum. Often the dielectric materials of the packaging and/or surface coating layers exhibit relatively low loss and abrupt changes in the refractive index at the layer boundaries can be observed as …

Analytical And Numerical Modeling Of Long Term Changes To Tides, Storm Surge, And Total Water Level Due To Bathymetric Changes And Surge Characteristics, Ramin Familkhalili

Dissertations and Theses

Natural and local anthropogenic changes in estuaries (e.g., sea-level rise, navigation channel construction and loss of wetlands) interact with each other and produce non-linear effects. There is also a growing recognition that tides in estuaries are not stationary. These factors together are changing the estuarine water level regime, however the implications for extreme water levels remain largely unknown. Changes over the past century in many estuaries, such as channel deepening and streamlining for navigation have significantly altered the hydrodynamics of long waves, often resulting in amplified tides (a ~85% increase in Wilmington, NC since 1900) and storm surge in estuaries. …

Strength Tuned Steel Eccentric Braced Frames, Hosam Abdullah Al-Azzawi

Dissertations and Theses

The primary component in eccentrically braced frames (EBF) is the link as its plastic strength controls the design of the frame as well as the entire building within which it is installed. EBFs are the first part of building design and every other component is sized based on the forces developed in the link. Oversized link elements lead to the use of unnecessary materials and can increase construction costs. Additionally, the advantages of using a continuous member of the same depth for both the link and the controller beam (in terms of the cost and the time) motivates researchers to …

Uhf And Microwave Phase-Modulated Scattering Array, Nasr Nomas Hussein Alkhafaji

Dissertations and Theses

This dissertation investigates the use an array of active nonlinear elements, with particular emphasis on controlling distortion products generated by nonlinear elements in space rather than using conventional ways such as transmission lines, waveguides, and power dividers and combiners. The nonlinear elements are made of assemblies of antennas and electronic switches, called modulated scatterers (MSs). These so-called MSs elements are utilized in a wide variety of applications such as radio frequency identification (RFID) systems, microwave imaging, Internet-of-Things sensors, etc. However, no research work has been reported in the literature regarding exploiting and controlling several distortion products generated by MSs at …

Seismic Performance Of Substandard Reinforced Concrete Bridge Columns Under Subduction-Zone Ground Motions, Alvaro Francisco Lopez Ibaceta

Dissertations and Theses

A large magnitude, long duration subduction earthquake is impending in the Pacific Northwest, which lies near the Cascadia Subduction Zone (CSZ). Great subduction zone earthquakes are the largest earthquakes in the world and are the sole source zones that can produce earthquakes greater than M8.5. Additionally, the increased duration of a CSZ earthquake may result in more structural damage than expected. Given such seismic hazard, the assessment of reinforced concrete substructures has become crucial in order to prioritize the bridges that may need to be retrofitted and to maintain the highway network operable after a major seismic event. Recent long …