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Full-Text Articles in Engineering

Evaluating Variability Of Urban Land Surface Temperatures Using Drone Observations, Joseph Naughton Jul 2019

Evaluating Variability Of Urban Land Surface Temperatures Using Drone Observations, Joseph Naughton

Master's Theses (2009 -)

Temperature represents one of the largest impairments for rivers and streams across the United States. In Wisconsin alone, over 17 miles of streams are impaired for temperature. This situation is projected to get worse as urban development and climate change accelerate thermal stress on aquatic environments. Management solutions require accurate and reliable models that represent rainfall-runoff temperature dynamics – particularly the characterization of land surface temperatures and how this translates to urban runoff. However, current models may not reflect the thermal profiles of real-world systems because they rely on in-situ equipment limited to point measurements. Limited studies have considered the variability ...


Design And Evaluation Of A Novel Ankle Joint For An Ankle Foot Orthosis For Individuals With Drop-Foot, Eileen Maya Baker Jul 2019

Design And Evaluation Of A Novel Ankle Joint For An Ankle Foot Orthosis For Individuals With Drop-Foot, Eileen Maya Baker

Master's Theses (2009 -)

Individuals who have had a stroke often ambulate with an ankle foot orthosis (AFO) to treat drop-foot, a common impairment preventing active ankle dorsiflexion. AFOs limit ankle plantarflexion or drop-foot, but also restrict ankle motion that introduces additional gait pathologies during ambulation. The goal of this study was to design a mechanical ankle joint for an articulated thermoplastic AFO to permit enhanced motion during stance. This novel ankle joint operated in two stages: 1) locked during swing to prevent drop-foot and 2) unlocked during stance to allow motion. This novel ankle joint was first tested with able-bodied subjects to ensure ...


Effect Of Low Reactivity Fuel On Reaction Wave Growth Of Dual-Fuel Stratified Mixtures In A Rapid Compression Machine, David J. Roulo Jul 2019

Effect Of Low Reactivity Fuel On Reaction Wave Growth Of Dual-Fuel Stratified Mixtures In A Rapid Compression Machine, David J. Roulo

Master's Theses (2009 -)

For over 40 years, researchers have been studying homogenous charge compression ignition (HCCI) as a combustion strategy to improve the efficiency and emissions of the internal combustion strategy. Although early results were promising, it has been since discovered that HCCI engines only operate to their potential over a narrow load band. To remedy this, introducing inhomogeneities has been suggested as a method of controlling HCCI combustion in such a way to improve its usefulness. One such inhomogeneity is referred to as fuel octane number stratification and consists of port injecting a low reactivity fuel, allowing it to become well mixed ...


Optimal Conditions For Measuring Ignition Quality In Non-Engine Tests, Ashley Hatzenbihler Jul 2019

Optimal Conditions For Measuring Ignition Quality In Non-Engine Tests, Ashley Hatzenbihler

Master's Theses (2009 -)

Experiments and simulation work were conducted to explore the conditions that influence ignition events in a constant volume environment. Experiments were conducted in a Fuel Ignition Tester, produced by CFR Engines, Inc., and in a prototype combustion chamber to observe the combustion of diesel fuels and primary reference fuels. These experiments attempted to isolate experimental conditions that would provide repeatable pressure measurements. These experiments showed that the fuel spray properties and the environmental conditions, such as initial temperature and initial pressure, are significantly influential in these results. Simulation work was conducted in Converge 2.2.0 to explore these conditions ...


Automated Shaped Charge Design: Applying Dakota Optimization To Cth Kinetic Energy Results, Sebastian Arcangelo Konewko Jul 2019

Automated Shaped Charge Design: Applying Dakota Optimization To Cth Kinetic Energy Results, Sebastian Arcangelo Konewko

Master's Theses (2009 -)

Advances in computational power present an opportunity to further optimize the design of an engineered energetic system. This work presents the application of a proposed optimization scheme which combines the shock-physics hydrocode CTH with the DAKOTA optimization package to automate shaped-charge jet design. The formation of an explosively driven hypervelocity jet is highly dependent on the original shaped charge liner geometry. By parameterizing this geometry, and by developing a characteristic objective function from CTH simulations, a process can be established where the Dakota code iteratively builds an optimal shaped charge. This work attempts to use this methodology to reproduce a ...


Effects Of Radiation And Egr On Pollutant Formation In High-Pressure Constant Volume Spray Combustion, Khaled Mosharraf Mosharraf Mukut Jul 2019

Effects Of Radiation And Egr On Pollutant Formation In High-Pressure Constant Volume Spray Combustion, Khaled Mosharraf Mosharraf Mukut

Master's Theses (2009 -)

Soot formation is a complex process and the actual soot formation methodology is still a mystery. Numerically modeling of soot requires successful coupling of turbulence, chemistry and radiation modeling. In the present study, a comprehensive sensitivity study is conducted to see the effect of radiation and exhaust gas recirculation (EGR) on soot and NOX formation in a high pressure spray combustion scenario. The spray-A case (n-dodecane as fuel) from Engine Combustion Network (ECN) is used as the target condition. Two different soot modeling approaches have been considered: a semi-empirical two-equation model and a method of moments with interpolative closure (MOMIC ...


Detecting Invasive Insects Using Unmanned Aerial Vehicles, Brian Stumph Jul 2019

Detecting Invasive Insects Using Unmanned Aerial Vehicles, Brian Stumph

Master's Theses (2009 -)

A key aspect to controlling and reducing the effects invasive insect specieshave on agriculture is to obtain knowledge about the migration patterns of thesespecies. Current state-of-the-art methods of studying these migration patternsinvolve a mark-release-recapture technique, in which insects are released afterbeing marked and researchers attempt to recapture them later. However, thisapproach involves a human researcher manually searching for these insects inlarge fields and results in very low recapture rates. This thesis proposes anautomated system for detecting released insects using an unmanned aerialvehicle. Our system utilizes ultraviolet lighting technology, digital cameras, andlightweight ...


Pedaling Asymmetry During Lower Limb Pedaling After Stroke, Benjamin Rappaport Jul 2019

Pedaling Asymmetry During Lower Limb Pedaling After Stroke, Benjamin Rappaport

Master's Theses (2009 -)

People with stroke pedal asymmetrically. There may be differences in their pedaling kinetics between their non-paretic and paretic lower limbs and compared to healthy age matched controls. Previous studies have measured pedaling related impairments and impairments with interlimb coordination using electromyography (EMG). These studies did not use torque as a measurement for pedaling related impairments and interlimb coordination impairments. Pedaling symmetry in the laboratory measuring the torque and work production will fill the gaps of the knowledge about motor compensation during lower limb pedaling. As well, pedaling symmetry has not been measured during fMRI because of the inability to measure ...


Analysis Of Bjt Colpitts Oscillators - Empirical And Mathematical Methods For Predicting Behavior, Nicholas Jon Stave Jul 2019

Analysis Of Bjt Colpitts Oscillators - Empirical And Mathematical Methods For Predicting Behavior, Nicholas Jon Stave

Master's Theses (2009 -)

Oscillator circuits perform two fundamental roles in wireless communication –the local oscillator for frequency shifting and the voltage-controlled oscillator formodulation and detection. The Colpitts oscillator is a common topology used for theseapplications. Because the oscillator must function as a component of a larger system, theability to predict and control its output characteristics is necessary. Textbooks treating thecircuit often omit analysis of output voltage amplitude and output resistance and theliterature on the topic often focuses on gigahertz-frequency chip-based applications.Without extensive component and parasitics information, it is often difficult to makesimulation software predictions agree with ...


Investigation Of Surface Topology Effects On Metal Flow Of Aluminum And Steel During Hot Compression, Andrew Richard Matcha Jul 2019

Investigation Of Surface Topology Effects On Metal Flow Of Aluminum And Steel During Hot Compression, Andrew Richard Matcha

Master's Theses (2009 -)

An investigation was conducted to study the effect of die surface roughness and lay on metal flow and the friction factor under lubricated hot compression. 6061-T6 aluminum and AISI 1018 steel rings and rectangular bar stock workpieces were compressed on H-13 tool steel platens of varying roughnesses ranging from Ra 0.25 – 6.1 µm (10 – 240 µin). Each platen was machined in such a way to ensure that the surface roughness would be unidirectional. Platen temperatures of 149 °C and 204 °C (300 °F and 400 °F) were used for all aluminum ring samples whereas platen temperatures ranging from ...


Local Density Parameters With Respect To Powder Metal Sintering Process, Jungu Kang Jul 2019

Local Density Parameters With Respect To Powder Metal Sintering Process, Jungu Kang

Master's Theses (2009 -)

Mapping of local density fractions and a mathematically approximated density fraction model of sintered powder metal were studied in this research. Specimens were studied utilizing an image analysis software, HCImage, and local density fraction maps were acquired for each sintering condition. A regression function of sintering temperature, sintering time, radius and depth was then derived from the local density fractions. The experimental procedures including specimen preparation, image analysis, and data analysis are demonstrated in detail within this research. Through the local density maps and the regression function, two objectives were sought as follow:1. Determination of the density fraction gradient ...


Computationally Efficient Optimization Of A Five-Phase Flux-Switching Pm Machine Under Different Operating Conditions, Hao Chen, Xiangdong Liu, Nabeel Demerdash, Ayman M. El-Refaie, Zhen Chen, Jiangbiao He May 2019

Computationally Efficient Optimization Of A Five-Phase Flux-Switching Pm Machine Under Different Operating Conditions, Hao Chen, Xiangdong Liu, Nabeel Demerdash, Ayman M. El-Refaie, Zhen Chen, Jiangbiao He

Electrical and Computer Engineering Faculty Research and Publications

This paper investigates the comparative design optimizations of a five-phase outer-rotor flux-switching permanent magnet (FSPM) machine for in-wheel traction applications. To improve the comprehensive performance of the motor, two kinds of large-scale design optimizations under different operating conditions are performed and compared, including the traditional optimization performed at the rated operating point and the optimization targeting the whole driving cycles. Three driving cycles are taken into account, namely, the urban dynamometer driving schedule (UDDS), the highway fuel economy driving schedule (HWFET), and the combined UDDS/HWFET, representing the city, highway, and combined city/highway driving, respectively. Meanwhile, the computationally efficient ...


Nematic Liquid Crystal Composite Materials For Dc And Rf Switching, Mohiuddin Munna, Farhana Anwar, Ronald A. Coutu Jr. Apr 2019

Nematic Liquid Crystal Composite Materials For Dc And Rf Switching, Mohiuddin Munna, Farhana Anwar, Ronald A. Coutu Jr.

Electrical and Computer Engineering Faculty Research and Publications

Liquid Crystals (LCs) are widely used in display devices, electro-optic modulators, and optical switches. A field-induced electrical conductivity modulation in pure liquid crystals is very low which makes it less preferable for direct current (DC) and radio-frequency (RF) switching applications. According to the literature, a conductivity enhancement is possible by nanoparticle doping. Considering this aspect, we reviewed published works focused on an electric field-induced conductivity modulation in carbon nanotube-doped liquid crystal composites (LC-CNT composites). A two to four order of magnitude switching in electrical conductivity is observed by several groups. Both in-plane and out-of-plane device configurations are used. In plane ...


Sensor Intrusion Detection In Control Systems Using Estimation Theory, Jiayi Su Apr 2019

Sensor Intrusion Detection In Control Systems Using Estimation Theory, Jiayi Su

Master's Theses (2009 -)

In this thesis, two different approaches to sensor intrusion detection are presented. In the first approach, an estimation algorithm using a bank of Kalman Filters is designed that is capable of estimating the intrusion signal when sensors are affected in control systems. The mathematical models of the control system will be estabilished and the system measurement will be shown and after that, various false signals, such as constant-type and ramp-type signal, will be selected as the intrusion signal to affect the system output mentioned above. The system measurement will be tested based on a bank of Kalman Filters. The probabilities ...


Detection And Characterization Of Actuator Attacks Using Kalman Filter Estimation, Yuqin Weng Apr 2019

Detection And Characterization Of Actuator Attacks Using Kalman Filter Estimation, Yuqin Weng

Master's Theses (2009 -)

In this thesis, two discrete-time control systems subject to noise, are modeled, analyzed and estimated. These systems are then subjected to attack by false signals such as constant and ramp signals. In order to find out how and when the control systems are being attacked by the false signals, several detection algorithms are applied to the systems. This work focuses on actuator attack detection. To detect the presence of false actuator signals, a bank of Kalman filters is set up which uses adaptive estimation and conditional probability density functions for detecting the false signals. The individual Kalman filters are each ...


Development Of A Quasi-Monte Carlo Method For Thermal Radiation, Joseph Farmer Apr 2019

Development Of A Quasi-Monte Carlo Method For Thermal Radiation, Joseph Farmer

Master's Theses (2009 -)

Radiative heat transfer in participating media is among the most challenging computational engineering problems due to the complex nonlinear, nonlocal nature of radiation transport. Many approximate methods have been developed in order to resolve radiative heat transfer in participating media; but approximate methods, by the nature of their approximations, suffer from various shortcomings both in terms of accuracy and robustness. The only methods that can resolve radiative transfer accurately in all configurations are the statistical Monte Carlo-based methods. While the Monte Carlo (MC) method is the most accurate method for resolving radiative heat transfer, it is also notoriously computationally prohibitive ...


Kinetic Analysis Of Biosolid Pyrolysis, William Regan Kreutter Apr 2019

Kinetic Analysis Of Biosolid Pyrolysis, William Regan Kreutter

Master's Theses (2009 -)

Waste reduction and energy recovery have been an environmental focus. Many of these solutions involve the thermal degradation of waste, such as household garbage or organic waste. To help reduce the negative environmental impact associated with processes like incineration, methods have been developed to utilize the carbonaceous material and energy contained in waste. Wastewater treatment plants are responsible for collecting and cleaning billions of gallons of sewage and stormwater each year. The water collected goes through multiple cleaning stages before being discharged into surface water. Sewage sludge, commonly referred to as biosolids, are produced during the process. Biosolids are carbon ...


The Characterization Of Char Particle Morphology And Its Effects On Combustion, Scott Jorgensen Apr 2019

The Characterization Of Char Particle Morphology And Its Effects On Combustion, Scott Jorgensen

Master's Theses (2009 -)

Char particle combustion typically occurs under internal diffusion control, which results in inter-particle reactant gradients. Reactant concentrations throughout the char’s carbon structure must be known in order to predict overall particle reaction rates. These concentrations can be predicted by analytical models; however, effects of char morphology are typically ignored within these simplified models. In order to incorporate these effects, the morphology of Illinois coal #6 was studied by visualizing their structure in three-dimensions through the use of micro-computed tomography. Morphological characteristics of macro-porosity, macro-porosity location, and wall thickness were then measured for the sampled char particles. The sampled char ...


Electrocoagulation-Electrooxidation For Mitigating Trace Organic Compounds In Model Source Waters, Donald R. Ryan Apr 2019

Electrocoagulation-Electrooxidation For Mitigating Trace Organic Compounds In Model Source Waters, Donald R. Ryan

Master's Theses (2009 -)

Conventional coagulation and oxidation are well suited for many drinking water operations to meet regulatory requirements for safe drinking water. However, these processes require auxiliary chemicals and materials that must be transported from off-site, which increases complexity of operations, and can pose difficulties for small treatment systems. Electrochemistry offers an innovative method to induce coagulation and oxidation processes for water treatment. Electrocoagulation (EC) together with electrooxidation (EO) is an attractive option for drinking water treatment systems because these processes generate iron coagulants using iron EC electrodes and oxidants (e.g., free chlorine and reactive oxygen species) using boron-doped diamond EO ...


Computational Characterization Of The Cellular Origins Of Electroencephalography, Shane Hesprich Apr 2019

Computational Characterization Of The Cellular Origins Of Electroencephalography, Shane Hesprich

Master's Theses (2009 -)

Electroencephalography (EEG) is a non-invasive technique used to measure brain activity. Despite its near ubiquitous presence in neuroscience, very little research has gone into connecting the electrical potentials it measures on the scalp to the underlying network activity which generates those signals. This results in most EEG analyses being more macroscopically focused (e.g. coherence and correlation analyses). Despite the many uses of macroscopically focuses analyses, limiting research to only these analyses neglects the insights which can be gained from studying network and microcircuit architecture. The ability to study these things through non-invasive techniques like EEG depends upon the ability ...


Impact Of Electrocoagulation Pretreatment On E. Coli Mitigation Using Electrooxidation, William Mcgregor Lynn Apr 2019

Impact Of Electrocoagulation Pretreatment On E. Coli Mitigation Using Electrooxidation, William Mcgregor Lynn

Master's Theses (2009 -)

Small drinking water systems serve approximately 20% of the US population, but they can struggle to comply with the Total Coliform Rule and the Disinfectant and Disinfection Byproduct Rule. Issues with insufficient funds to effectively treat the water and difficulties with the transportation of required chemicals can affect compliance. Electrochemical processes may offer an alternative approach for small water systems as they have demonstrated some advantages over traditional treatments, such as reduced handling and storage of chemicals and cost effectiveness. Sequential electrochemical processes have yet to be tested for the treatment of E. coli in drinking waters. In this study ...


Multi-Scale Traction Dynamics In Obliquely Impacted Polymer-Metal Targets, Peter Anthony Sable Apr 2019

Multi-Scale Traction Dynamics In Obliquely Impacted Polymer-Metal Targets, Peter Anthony Sable

Dissertations (2009 -)

The characterization of polymer behavior at high strain-rates is a criticalarea of research driven by their use as adhesives, structural components, or evenas binders for energetic systems. Current experimentation has been limited to eitherlow strain-rate mechanical testing or plane strain (uniaxial) impact testing.As such, more complicated loading conditions at high strain-rate have remainedunexplored. Particularly of interest include the rate dependencies of polymerstrength as well as interface traction behaviors like adhesion and dynamic frictionphenomena. To investigate these characteristics, fully dense, high durometer,polyurethane (PUR) and epoxy were subjected to combined pressure-shear loadingvia oblique ...


Advanced Silicon Carbide Based Fault-Tolerant Multilevel Converters, Ramin Katebi Apr 2019

Advanced Silicon Carbide Based Fault-Tolerant Multilevel Converters, Ramin Katebi

Dissertations (2009 -)

The number of safety-critical loads in electric power areas have been increasing drastically in the last two decades. These loads include the emerging more-electric aircraft (MEA), uninterruptible power supplies (UPS), high-power medical instruments, electric and hybrid electric vehicles (EV/HEV) and ships for military use, electric space rovers for space exploration and the like. This dissertation introduces two novel fault-tolerant three-level power converter topologies, named advanced three-level active neutral point clamped converter (A3L-ANPC) and advanced three-level active T-Type (A3L-ATT) converter. The goal of these converters is to increase the reliability of multilevel power converters used in safety-critical applications.These new ...


Improved Reliability Of Stormwater Detention Basin Performance Through Water Quality Data-Informed Real-Time Control, Sazzad Sharior Apr 2019

Improved Reliability Of Stormwater Detention Basin Performance Through Water Quality Data-Informed Real-Time Control, Sazzad Sharior

Master's Theses (2009 -)

The objective of stormwater detention basins is to capture stormwater runoff to reduce and delay peak flow and to improve the water quality. These objectives can be improved upon by actively controlling the outflow of the basins rather than traditional passive outflow structures. There are studies demonstrating the performance of the active controls that respond in real-time to basin hydraulics, detention time, and rainfall forecasts. We hypothesize that the performance of these active controls can be improved upon by incorporating real-time water quality data streams into the control algorithm. Furthermore, we hypothesize that performance of these active controls also depends ...


Shock Compaction Of Graphene Doped Yttria Stabilized Zirconia: An Experimental And Computational Study, Christopher Rueben Johnson Apr 2019

Shock Compaction Of Graphene Doped Yttria Stabilized Zirconia: An Experimental And Computational Study, Christopher Rueben Johnson

Master's Theses (2009 -)

Yttria stabilized zirconia (YSZ) is a broadly used ceramic due to its impeccable hardness and thermal stability. Limitations of the material, however, subsist within its fracture toughness. Literature indicates that shock consolidation may enable production of composite YSZ and graphene mixtures with improved fracture toughness and other material properties while maintaining the material’s nanostructure dimensionality. Therefore, investigation of the compaction phenomena at non-equilibrium states will provide informative results to be used in the fabrication of bulk graphene-YSZ composites. Computational molecular dynamics (MD) simulations and impact experiments are conducted to explore and characterize the dynamic response of the YSZ variants ...


Ergonomics Study Of A Helmet-Mounted Augmented Reality System For Coal Power Plant Workers, Ashley M. Toll Apr 2019

Ergonomics Study Of A Helmet-Mounted Augmented Reality System For Coal Power Plant Workers, Ashley M. Toll

Master's Theses (2009 -)

Augmented reality (AR) is a technology that combines real and virtual information presented to the user in an interactive way in real time. The Microsoft HoloLens and RealWear HMT-1 are two common types of head-mounted AR available to industrial field workers. These two AR systems were tested on how they affected indicators of eye strain and forces of the neck and shoulder muscles for electric utility power plant operators while they performed five routine inspection tasks using coal burning equipment. The inspection tasks were conducted under three conditions: HoloLens, HMT-1, and absence of AR (normal). The duration of the inspection ...


Correlations Between Shoulder Rotational Motion, Strength Measures And Throwing Biomechanics In Collegiate Baseball Pitchers, Austin William Higgins Apr 2019

Correlations Between Shoulder Rotational Motion, Strength Measures And Throwing Biomechanics In Collegiate Baseball Pitchers, Austin William Higgins

Master's Theses (2009 -)

Pitching involves high stresses to the arm that may alter soft tissue responsible for controlling biomechanics. It has been hypothesized that imbalances in strength and flexibility of the dominant shoulder lead to decreased performance and increased injury risk, but it is not fully known what specific pitching biomechanics are altered. There is a critical need to determine correlations between shoulder rotational strength, range of motion and pitching kinetics. Without such knowledge, identifying potential for injury from shoulder imbalances will likely remain difficult and invasive. The goal of this study was to determine correlations between shoulder rotational strength and range of ...


Liquid Flowmeter Using Thermal Measurement; Design And Application, Woojae Chung Apr 2019

Liquid Flowmeter Using Thermal Measurement; Design And Application, Woojae Chung

Master's Theses (2009 -)

This thesis presents flowmeter devices which can measure flowrate, pressure and temperature offlowing liquid samples using thermal measurement method. Typical thermal mass flowmeter usesthermal properties of materials to obtain flow features only for gases. We designed and fabricatedflowmeter devices with various functionalities such as: measuring properties of flowing liquid andidentifying the type of liquid samples.Thermal measurement methods using temperature sensor is a key of our flowmeter’s workingprinciple. The thermal mass flowmeter consists of a glass capillary, a tungsten wire heater, and aresistance temperature detector (RTD) sensor. The heater and sensors are integrated ...


Iron-Enhanced Mitigation Of Viruses In Drinking Water, Joseph Aiden Heffron Apr 2019

Iron-Enhanced Mitigation Of Viruses In Drinking Water, Joseph Aiden Heffron

Dissertations (2009 -)

Waterborne viruses are ubiquitous in the environment and present a global threat to public health. Previous research has suggested that iron-based water treatment has promise as a low-cost, non-toxic means of virus mitigation. In particular, zero-valent and ferrous iron have shown evidence of inactivating bacteria and viruses. The purpose of this research was to elucidate the relationship between iron oxidation and virus inactivation and determine if iron-based inactivation can enhance two water treatment processes, electrocoagulation and electrooxidation, for virus mitigation. This research first investigated bacteriophage inactivation due to ferrous oxidation in batch tests using ferrous chloride salt. Ferrous iron oxidation ...


Passive Compliance Control Of Redundant Serial Manipulators, Jacob J. Rice Apr 2019

Passive Compliance Control Of Redundant Serial Manipulators, Jacob J. Rice

Dissertations (2009 -)

Current industrial robotic manipulators, and even state of the art robotic manipulators, are slower and less reliable than humans at executing constrained manipulation tasks, tasks where motion is constrained in some direction (e.g., opening a door, turning a crank, polishing a surface, or assembling parts). Many constrained manipulation tasks are still performed by people because robots do not have the manipulation ability to reliably interact with a stiff environment, for which even small commanded position error yields very high contact forces in the constrained directions. Contact forces can be regulated using compliance control, in which the multi-directional elastic behavior ...