Engineering Commons^™

Cooperative Remote Sensing And Actuation Using Networked Unmanned Vehicles, Haiyang Chao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on how to design and employ networked unmanned vehicles for remote sensing and distributed control purposes in the current information-rich world. The target scenarios are environmental or agricultural applications such as river/reservoir surveillance, wind profiling measurement, and monitoring/control of chemical leaks, etc. AggieAir, a small and low-cost unmanned aircraft system, is designed based on the remote sensing requirements from environmental monitoring missions. The state estimation problem and the advanced lateral flight controller design problem are further attacked focusing on the small unmanned aerial vehicle (UAV) platform. Then the UAV-based remote sensing problem is focused with further flight …

Multivariate Bayesian Machine Learning Regression For Operation And Management Of Multiple Reservoir, Irrigation Canal, And River Systems, Andres M. Ticlavilca

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The principal objective of this dissertation is to develop Bayesian machine learning models for multiple reservoir, irrigation canal, and river system operation and management. These types of models are derived from the emerging area of machine learning theory; they are characterized by their ability to capture the underlying physics of the system simply by examination of the measured system inputs and outputs. They can be used to provide probabilistic predictions of system behavior using only historical data. The models were developed in the form of a multivariate relevance vector machine (MVRVM) that is based on a sparse Bayesian learning machine …

Effects Of Static Stretching On Foot Velocity During The Instep Soccer Kick, Craig D. Workman

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to assess the acute effects of static stretching on foot velocity at impact with a soccer ball. Eighteen Division I female soccer athletes underwent two test conditions separated by 48 hr. Each condition was randomly assigned and began by placing four retro-reflective markers on bony landmarks of the ankle (total of eight markers, four on each ankle). One condition was the no-stretch condition, in which each participant performed a self-paced jog for 5 min as a warm-up, and then sat quietly for 6 min before performing three maximal instep kicks into a net. The …

Constraint Programming Techniques For Generating Efficient Hardware Architectures For Field Programmable Gate Arrays, Atul Kumar Shah

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This thesis presents an approach for modeling and generating efficient hardware architectures using constraint programming techniques, targeting field programmable gate arrays (FPGAs). The focus of this thesis is the derivation of optimal or near-optimal schedules for streaming applications from data flow graphs (DFGs). The resulting schedules are then used to facilitate the architecture generation process. Most streaming applications, like digital singal processing (DSP) algorithms, are repetitive in nature: the same computation is performed on different data items. This repetitive nature of streaming applications can be used to expose additional parallelism available across different iterations, by creating multiple instances of the …

Distributed Hydrological Modeling Using Soil Depth Estimated Based On Landscape Variables From Enhanced Terrain Analysis, Teklu K. Tesfa

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The spatial patterns of land surface and subsurface characteristics determine the spatial heterogeneity of hydrological processes. Soil depth is one of these characteristics and an important input parameter required by distributed hydrological models that explicitly represent spatial heterogeneity. Soil is related to topography and land cover due to the role played by topography and vegetation in affecting soil-forming processes. The research described in this dissertation addressed the development of statistical models that predict the soil depth pattern over the landscape; derivation of new topographic variables evaluated using both serial and parallel algorithms; and evaluation of the impacts of detailed soil …

Full-Scale Testing Of 40 Year Old Prestressed Aashto Girders That Have Been Retrofitted In Shear By Externally Applied Carbon Fiber Reinforced Polymer Wraps, David A. Petty

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Utah Department of Transportation (UDOT) is interested in the application of rehabilitation techniques to strengthen their AASTHO prestressed bridge girders for shear. Utah's bridges are exposed to deterioration from rain, snow, and the introduction of salt for ice removable. This requires innovative rehabilitation techniques to address the deteriorations of their highway bridges, especially the ends of bridge girders where water and salt are more common due to construction joints. Carbon Fiber Reinforced Polymers (CFRP) are becoming more prevalent as a tool in highway bridge rehabilitation.

This research investigates the application of various CFRP systems that can be used as …

Analysis Of Square-Root Kalman Filters For Angles-Only Orbital Navigation And The Effects Of Sensor Accuracy On State Observability, Jason Knudsen Schmidt

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Angles-only navigation is simple, robust, and well proven in many applications. However, it is sometimes ill-conditioned for orbital rendezvous and proximity operations because, without a direct range measurement, the distance to approaching satellites must be estimated by firing thrusters and observing the change in the target's bearing. Nevertheless, the simplicity of angles-only navigation gives it great appeal. The viability of this technique for relative navigation is examined by building a high-fidelity simulation and evaluating the sensitivity of the system to sensor errors. The relative performances of square-root filtering methods, including Potter, Carlson, and UD factorization filters, are compared to the …

Changes In Hybrid Poplar Endophytic Microbial Diversity In Response To Trichloroethylene Exposure, Jared S. Ervin

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Remediation of trichloroethylene (TCE) is a major priority for many contaminated sites all over the industrialized world including Hill Air Force Base, UT (HAFB). Phytoremediation as part of a cleanup strategy is an appealing option, and trees at HAFB have been studied to this end. Trees have also been used to delineate groundwater plumes because the passive uptake of organic contaminants by trees generally results in a direct relationship between tree and groundwater TCE concentrations if the trees are using the contaminated groundwater. However, the concentrations of plant-produced TCE metabolites can vary greatly. It was hypothesized that the endophytic microbial …

Transesterification And Recovery Of Intracellular Lipids Using A Single Step Reactive Extraction, Daniel R. Nelson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A single-step, extractive reaction for extraction of lipids such as biodiesel components, omega-3 fatty acids, or other triglycerides from microbial cells was examined. Conventional methods for lipid extraction use toxic solvents, and require multiple steps and long processing times. When the goal is to produce fatty acid methyl esters or FAMEs, the extracted lipids are subjected to a separate transesterification reaction with simple alcohols in the presence of an acid or base catalyst. A simplified, single-step reactive extraction method can be applied that combines the sequential extraction followed by transesterification using acidified alcohols - a process known as in situ …

Decentralized Coordination Of Multiple Autonomous Vehicles, Yongcan Cao

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

This dissertation focuses on the study of decentralized coordination algorithms of multiple autonomous vehicles. Here, the term decentralized coordination is used to refer to the behavior that a group of vehicles reaches the desired group behavior via local interaction. Research is conducted towards designing and analyzing distributed coordination algorithms to achieve desired group behavior in the presence of none, one, and multiple group reference states.

Decentralized coordination in the absence of any group reference state is a very active research topic in the systems and controls society. We first focus on studying decentralized coordination problems for both single-integrator kinematics and …

Accelerated Frame Data Relocation On Xilinx Field Programmable Gate Array, Ramachandra Kallam

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Emerging reconfiguration techniques that include partial dynamic reconfiguration and partial bitstream relocation have been addressed in the past in order to expose the flexibility of field programmable gate array at runtime. Partial bitstream relocation is a technique used to target a partial bitstream of a partial reconfigurable region (PRR) onto other identical reconfigurable regions inside an FPGA, while partial dynamic reconfiguration is used to target a single reconfigurable region. Prior works in this domain aim to minimize "relocation time" with the help of on-chip or on-line processing. In this thesis, a novel PRR-PRR relocation algorithm is proposed and implemented both …

In-Pile Thermal Conductivity Measurement Methods For Nuclear Fuels, Brandon S. Fox

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Measuring nuclear fuel thermal conductivity in-pile can provide much needed data for understanding fuel performance during irradiation and yield thermophysical property data needed for simulation codes and fuel databases. The objective of this research is to develop and compare two in-pile thermal conductivity methods in a laboratory setting using surrogate fuel materials.

A steady-state radial heat flow method was investigated to understand its viability as an in-pile steady-state thermal conductivity technique. By using Joule heating to simulate volumetric heat generation within a surrogate fuel rod, thermal conductivity was measured with two thermocouples at different radial positions within the rod. Examinations …

Neural Networks And The Natural Gradient, Michael R. Bastian

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Neural network training algorithms have always suffered from the problem of local minima. The advent of natural gradient algorithms promised to overcome this shortcoming by finding better local minima. However, they require additional training parameters and computational overhead. By using a new formulation for the natural gradient, an algorithm is described that uses less memory and processing time than previous algorithms with comparable performance.

Signal Processing On Waveform Data From The Eyesafe Ladar Testbed (Elt), K.D. Neilsen, Scott E. Budge, R.T. Pack

Electrical and Computer Engineering Faculty Publications

The Eyesafe Ladar Test-bed (ELT) is a raster scanning, single-beam, energy-detection ladar with the capability of digitizing and recording the return pulse waveform at 2 GHz in the field for off-line 3D point cloud formation research in the laboratory. The ELT serves as a prime tool in understanding the behavior of ladar waveforms. Signal processing techniques have been applied to the ELT waveform in an effort to exploit the signal with respect to noise reduction, range resolution improvement, and ability to discriminate between two surfaces of similar range. This paper presents a signal processing method used on the ELT waveform. …

Follow Up Nucleate Boiling On-Flight Experiment, Andrew Fassmann

Presentations

No abstract provided.

Evaluation Of Alternative Formulae For Calculation Of Surface Temperature In Snowmelt Models Using Frequency Analysis Of Temperature Observations, C. H. Luce, David G. Tarboton

Civil and Environmental Engineering Faculty Publications

The snow surface temperature is an important quantity in the snow energy balance, since it modulates the exchange of energy between the surface and the atmosphere as well as the conduction of energy into the snowpack. It is therefore important to correctly model snow surface temperatures in energy balance snowmelt models. This paper focuses on the relationship between snow surface temperature and conductive energy fluxes that drive the energy balance of a snowpack. Time series of snow temperature at the surface and through the snowpack were measured to examine energy conduction in a snowpack. Based on these measurements we calculated …

Smooth-Wall Boundary Conditions For Dissipation-Based Turbulence Models, W. F. Phillips, Doug F. Hunsaker, Robert E. Spall

Mechanical and Aerospace Engineering Faculty Publications

It is shown that the smooth-wall boundary conditions specified for commonly used dissipation-based turbulence models are mathematically incorrect. It is demonstrated that when these traditional wall boundary conditions are used, the resulting formulations allow an infinite number of solutions. Furthermore, these solutions do not enforce energy conservation and they do not properly enforce the no-slip condition at a smooth surface. This is true for all dissipation-based turbulence models, including the k-ε, k-ω, and k-ζ models. Physically correct wall boundary conditions must force both k and its gradient to zero at a smooth wall. Enforcing these two boundary conditions on k …

Spacecraft Coating-Induced Charging: A Materials And Modeling Study Of Environmental Extreme, Michelle M. Donegan, Jennifer L. Sample, John R. Dennison, R. Hoffman

All Physics Faculty Publications

As mankind reaches to explore extreme environments in space, the application of ceramics surface coatings is increasing. The 2005 mission concept for Solar Probe used a unique design to achieve the necessary thermal control for a very close approach to the solar corona, including the use of a highly refractory, electrically insulating ceramic coating over a carbon-carbon composite heat shield. The proposed trajectory takes the spacecraft from a Jovian fly-by to within 4 solar radii of the Sun, spanning 5 orders of magnitude in solar radiation and solar wind plasma density as well as spacecraft temperatures from <100 K to >2000 K. Using …

Funboe (Follow-Up Nucleate Boiling On-Flight Experiment), Getaway Special Team 2010

Education and Outreach

No abstract provided.

Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett

Education and Outreach

No abstract provided.

Gravitational Effects On Thin-Wire Subcooled Nucleate Boiling Dynamics, Justin Koeln, Andrew Fassmann, Troy Munro, Rob Barnett

Presentations

No abstract provided.

Hot Water, Dry Streams: A Tale Of Two Trout, Jack R. Tuholske

All In-stream Flows Material

Norman Maclean’s timeless memoir A River Runs Through It begins with the reflection that in his household “there was no clear line between religion and fly fishing.”¹ That zeal remains today; nearly 30 million Americans call themselves fishermen.² Anglers devoted an aggregate of 517 million user-days pursuing their passion in 2006 and spent billions of dollars to support it.³ Fishing in the western United States holds a special place in fishing lore the world over and for good reason. From the great trout waters of Montana, to the salmon-laden rivers of the west coast, to the sparkling …

A Comparative Guide To The Western States' Public Trust Doctrines: Public Values, Private Rights, And The Evolution Toward An Ecological Public Trust, Robin Kundis Craig

All In-stream Flows Material

In the arid West, balancing private needs for fresh water to consume against the public values-recreational, aesthetic, and ecological-served by leaving fresh water in situ has tended to favor the private use side. Evidence of this result is both massive and minor, ranging from California's multi-billion-dollar water transportation system,¹ to the routine de-watering of the Colorado River so that little to no water reaches the Sea of Cortez,² to water-related Endangered Species Act lawsuits in dozens of watersheds. ³

Design Assessment: Consumer Reports Style, Todd R. Kelley

Publications

The article analyzes a design assessment-based activity, in which students are asked to evaluate an existing technology through a Consumer Reports-style approach. According to H. Petroski, the exposure of students to several design examples is important to start learning the basic elements needed in the design process. It claims that the activity will enable students to sharpen their knowledge in several areas including identifying design constraints and criteria, training via study of open designs, and practicing engineering design methods for optimization. It suggests that these are important skills for creating the student's capacity to undertake bigger design activities.

The Gas Team And Nasa (Aka Boil, Boil, Toil And Trouble), Get Away Special Team 2010

Education and Outreach

No abstract provided.

Engineering Professional Development Design For Secondary School Teachers: A Multiple Case Study, Jenny L. Daugherty

Publications

The effectiveness of teachers has been regarded as crucial to the success of standards-based reform (Fishman, Marx, Best, & Tal, 2003). Research, particularly within science and mathematics, has underscored the need for professional development to help teachers understand (a) subject matter, (b) learners and learning, and (c) teaching methods (Loucks-Horsley, 1999). In addition to focusing on teacher professional development, national reform efforts have also emphasized science, technology, engineering, and mathematics (STEM) education (i.e., Rising Above the Gathering Storm, NRC, 2006). While substantial work has been conducted in mathematics and science, the efforts in technology and engineering education are much less …

Pltw And Epics‐High: Curriculum Comparisons To Support Problem Solving In The Context Of Engineering Design, Todd Kelley, Daniel C. Brenner, John T. Pieper

Reports of Center Studies

A comparative study was conducted to compare two approaches to engineering design curriculum between different schools (inter-school) and between two curricular approaches, Project Lead the Way (PLTW) and Engineering Projects in Community Service (EPIC High) (inter-curricular). The researchers collected curriculum materials, including handouts, lesson plans, guides, presentation files, design descriptions, problem statements, and support guides. The researchers conducted observations in the classrooms to collect qualitative indicators of engineering/technology reasoning, collect data on the nature of students‟ questions, how students define problems, and operate within the constraints of a design problem.

Observational studies were conducted with students participating in Project Lead …

Integrating Seasonal Climate Forecasts Into Institutional Decision-Making Processes, David Watkins

All ECSTATIC Materials

It is often challenging to integrate climate forecast use into actual decision-making processes, even when modeling demonstrates significant benefits from its use. Decision-making processes are guided by both formal policy frameworks, and the particular institutional structures under which decision-makers must operate. In addition, water is shared across multiple stakeholders, who are often represented by specific government or private sector agencies. These agencies face different costs depending upon the outcome of a forecast, and different preferences for risk. Depending upon the institutional and political arrangements for how decisions are made, these stakeholder interests may figure more or less strongly in water …

Xperts And Novices: Differences In Their Use Of Mental Representation And Metacognition In Engineering Design, Raymond Anthony Dixon

Dissertations

Research shows that mental representation such as analogical reasoning is a fundamental cognitive tool for design problem solving (Daugherty & Mentzer, 2008; Hey, Lensey, Agogino, & Wood, 2008; Lewis, 2008). Not much is known, however, about the way students and professional engineers actively generate and change their mental representation when solving a engineering design problem. There are very few studies that show how different types of mental representations; such as metaphors, propositions, and analogies; interplay with higher order cognitive processes; such as planning, monitoring, and evaluation; as engineering designers navigate their problem and solution spaces. This empirical study investigated the …

A Case Study: Teaching Engineering Concepts In Science, David R. Stricker

Reports of Center Studies

This study was conducted to describe a teacher developed high school engineering course, to identify teaching strategies used in the process of delivering math and science literacy through this course, to identify challenges and constraints that occurred during its development and delivery, and to describe the strategies that were used to overcome those obstacles.

A case study was conducted using semi-structured interviews with the engineering instructor at Benilde-St. Margaret's in St. Louis Park, Minnesota. In addition, the researcher conducted classroom observations and reviewed instructional materials, teacher lesson plans, and teacher journals.

Themes that developed regarding the strategies used to deliver …