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Analysis And Visualization Of Flow Fields Using Information-Theoretic Techniques And Graph-Based Representations, Jun Ma

Dissertations, Master's Theses and Master's Reports - Open

Three-dimensional flow visualization plays an essential role in many areas of science and engineering, such as aero- and hydro-dynamical systems which dominate various physical and natural phenomena. For popular methods such as the streamline visualization to be effective, they should capture the underlying flow features while facilitating user observation and understanding of the flow field in a clear manner.

My research mainly focuses on the analysis and visualization of flow fields using various techniques, e.g. information-theoretic techniques and graph-based representations. Since the streamline visualization is a popular technique in flow field visualization, how to select good streamlines to capture flow …

Computational Study Of Microstructure-Propertymechanism Relations In Ferroic Composites, Fengde D. Ma

Dissertations, Master's Theses and Master's Reports - Open

Ferroic materials, as notable members of smart materials, have been widely used in applications that perform sensing, actuation and control. The macroscopic property change of ferroic materials may become remarkably large during ferroic phase transition, leading to the fact that the macroscopic properties can be tuned by carefully applying a suitable external field (electric, magnetic, stress). To obtain an enhancement in physical and/or mechanical properties, different kinds of ferroic composites have been fabricated. The properties of a ferroic composite are determined not only by the properties and relative amounts of the constituent phases, but also by the microstructure of individual …

Spacecraft Attitude Control Using Magnetic Actuators, Karthik Mysore Srinivasa

Dissertations, Master's Theses and Master's Reports - Open

This report presents a study on the problem of spacecraft attitude control using magnetic actuators. Several existing approaches are reviewed and one control strategy is implemented and simulated. A time-varying feedback control law achieving inertial pointing for magnetically actuated spacecraft is implemented. The report explains the modeling of the spacecraft rigid body dynamics, kinematics and attitude control in detail.

Besides the fact that control laws have been established for stabilization around local equilibrium, this report presents the results of a control law that yields a generic, global solution for attitude stabilization of a magnetically actuated spacecraft. The report also involves …

Bias-Corrected Maximum Likelihood Estimation Of The Parameters Of The Weighted Lindley Distribution, Wentao Wang

Dissertations, Master's Theses and Master's Reports - Open

This report discusses the calculation of analytic second-order bias techniques for the maximum likelihood estimates (for short, MLEs) of the unknown parameters of the distribution in quality and reliability analysis. It is well-known that the MLEs are widely used to estimate the unknown parameters of the probability distributions due to their various desirable properties; for example, the MLEs are asymptotically unbiased, consistent, and asymptotically normal. However, many of these properties depend on an extremely large sample sizes. Those properties, such as unbiasedness, may not be valid for small or even moderate sample sizes, which are more practical in real data …

Double Vault Composting Latrines In Rural Paraguay : Feasible Construction And Optimal Use, Paul T. Pebler

Dissertations, Master's Theses and Master's Reports - Open

Water resource depletion and sanitation are growing problems around the world. A solution to both of these problems is the use of composting latrines, as it requires no water and has been recommended by the World Health Organization as an improved sanitation technology. However, little analysis has been done on the decomposition process occurring inside the latrine, including what temperatures are reached and what variables most affect the composting process. Having better knowledge of how outside variables affect composting latrines can aid development workers on the choice of implementing such technology, and to better educate the users on the appropriate …

Characterization Of Electrodeposited Polyaniline Biosensor Platform For Escherichia Coli O157:H7 Detection, Sterling Prince

Dissertations, Master's Theses and Master's Reports - Open

Amperometric electrodeposition has been used to obtain uniform, conductive, and repeatable polyaniline (PANi) thin films for use in nano scaled biochemical sensors. This report describes the characterization of these films. Techniques such as ellipsometry were used to test repeatability of the deposition and the uniformity of the deposited thin films. Raman spectroscopy was utilized to confirm the composition of the deposited PANi thin films. Fluorescence microscopy was used to determine the immobilization of antibodies to the PANi thin films using biotin-avidin interactions, as well as the density of active binding sites. Ellipsometry results demonstrated that biomolecules could be immobilized on …

Investigating Within-Canopy Variation Of Functional Traits And Cellular Structure Of Sugar Maple (Acer Saccharum) Leaves, Adam P. Coble

Dissertations, Master's Theses and Master's Reports - Open

Patterns of increasing leaf mass per area (LMA), area-based leaf nitrogen (N_area), and carbon isotope composition (δ13C) with increasing height in the canopy have been attributed to light gradients or hydraulic limitation in tall trees. Theoretical optimal distributions of LMA and N_area that scale with light maximize canopy photosynthesis; however, sub-optimal distributions are often observed due to hydraulic constraints on leaf development. Using observational, experimental, and modeling approaches, we investigated the response of leaf functional traits (LMA, density, thickness, and leaf nitrogen), leaf carbon isotope composition (δ13C), and cellular structure to light availability, height, and leaf water …

State Of Charge Balancing Droop Control, Rui Hu

Dissertations, Master's Theses and Master's Reports - Open

This thesis presents a load sharing method applied in a distributed micro grid system. The goal of this method is to balance the state-of-charge (SoC) of each parallel connected battery and make it possible to detect the average SoC of the system by measuring bus voltage for all connected modules. In this method the reference voltage for each battery converter is adjusted by adding a proportional SoC factor. Under such setting the battery with a higher SoC will output more power, whereas the one with lower SoC gives out less. Therefore the higher SoC battery will use its energy faster …

Building A Discourse: Bridging The Gap Between New Media's Convergence And Rhetoric And Composition's Multimodality, Katherine G. Aho

Dissertations, Master's Theses and Master's Reports - Open

My dissertation emphasizes the use of narrative structuralism and narrative theories about storytelling in order to build a discourse between the fields of New Media and Rhetoric and Composition. Propp's morphological analysis and the breaking down of stories into component pieces aides in the discussion of storytelling as it appears in and is mediated by digital and computer technologies. New Media and Rhetoric and Composition are aided by shared concerns for textual production and consumption.

In using the notion of "kairotic reading" (KR), I show the interconnectedness and interdisciplinarity required in the development of pedagogy utilized to teach students to …

Synthetic Oligodeoxynucleotide Purification Via Catching By Polymerization, Suntara Fueangfung

Dissertations, Master's Theses and Master's Reports - Open

Large quantities of pure synthetic oligodeoxynucleotides (ODNs) are important for preclinical research, drug development, and biological studies. These ODNs are synthesized on an automated synthesizer. It is inevitable that the crude ODN product contains failure sequences which are not easily removed because they have the same properties as the full length ODNs. Current ODN purification methods such as polyacrylamide gel electrophoresis (PAGE), reversed-phase high performance liquid chromatography (RP HPLC), anion exchange HPLC, and affinity purification can remove those impurities. However, they are not suitable for large scale purification due to the expensive aspects associated with instrumentation, solvent demand, and high …

Extraction Of Pictorial Energy Information From Campus Unmetered Buildings Using Image Processing Techniques, Yachen Tang

Dissertations, Master's Theses and Master's Reports - Open

In recent years, advanced metering infrastructure (AMI) has been the main research focus due to the traditional power grid has been restricted to meet development requirements. There has been an ongoing effort to increase the number of AMI devices that provide real-time data readings to improve system observability. Deployed AMI across distribution secondary networks provides load and consumption information for individual households which can improve grid management. Significant upgrade costs associated with retrofitting existing meters with network-capable sensing can be made more economical by using image processing methods to extract usage information from images of the existing meters. This thesis …

Evaluation Of Magnesium As A Hall Thruster Propellant, Mark A. Hopkins

Dissertations, Master's Theses and Master's Reports - Open

In this study, the use of magnesium as a Hall thruster propellant was evaluated. A xenon Hall thruster was modified such that magnesium propellant could be loaded into the anode and use waste heat from the thruster discharge to drive the propellant vaporization. A control scheme was developed, which allowed for precise control of the mass flow rate while still using plasma heating as the main mechanism for evaporation. The thruster anode, which also served as the propellant reservoir, was designed such that the open area was too low for sufficient vapor flow at normal operating temperatures (i.e. plasma heating …

Advanced Computational Modeling Of The Internal Structure Of Smart Wind-Turbine Blades, Sanket Seetaram Bhogle

Dissertations, Master's Theses and Master's Reports - Open

Implementation of stable aeroelastic models with the ability to capture the complex features of Multi concept smartblades is a prime step in reducing the uncertainties that come along with blade dynamics. The numerical simulations of fluid structure interaction can thus be used to test a realistic scenarios comprising of full-scale blades at a reasonably low computational cost.

A code which was a combination of two advanced numerical models was designed and was run with the help of paralell HPC supercomputer platform. The first model was based on a variation of dimensional reduction technique proposed by Hodges and Yu. This model …

Improving Flow Distribution In Small-Scale Water-Supply Systems Through The Use Of Flow-Reducing Discs And Methods For Analyzing The Effectiveness Of Solar Powered Pumping For A Drinking Water Supply In Rural Panama, Briana I. Drake

Dissertations, Master's Theses and Master's Reports - Open

As continued global funding and coordination are allocated toward the improvement of access to safe sources of drinking water, alternative solutions may be necessary to expand implementation to remote communities.

This report evaluates two technologies used in a small water distribution system in a mountainous region of Panama; solar powered pumping and flow-reducing discs. The two parts of the system function independently, but were both chosen for their ability to mitigate unique issues in the community. The design program NeatWork and flow-reducing discs were evaluated because they are tools taught to Peace Corps Volunteers in Panama.

Even when ample water …

Access Control Programming Library And Exploration System, Zhitao Qiu

Dissertations, Master's Theses and Master's Reports - Open

The high complexity of advanced security models in the modern trusted systems requires an effective formal education for students. Education access control tools have been promoted. Though they can benefit the learning through analyzing or visualizing access control policies, few of them are designed to teach development of access control policies.

In this report, we propose an access control programming library which can provide students hand-on experience with the effect of an access control policy on a running program. A student can write a policy and then run programs under the policy. The Programming Library provides a system call wrapper …

Mower : A New Design For Non-Blocking Misprediction Recovery, Zhaoxiang Jin

Dissertations, Master's Theses and Master's Reports - Open

Mower is a micro-architecture technique which targets branch misprediction penalties in superscalar processors. It speeds-up the misprediction recovery process by dynamically evicting stale instructions and fixing the RAT (Register Alias Table) using explicit branch dependency tracking. Tracking branch dependencies is accomplished by using simple bit matrices. This low-overhead technique allows overlapping of the recovery process with instruction fetching, renaming and scheduling from the correct path. Our evaluation of the mechanism indicates that it yields performance very close to ideal recovery and provides up to 5% speed-up and 2% reduction in power consumption compared to a traditional recovery mechanism using a …

Fossil Plants And Palynomorphs From The Late Paleozoic Cutler Formation, Eastern Paradox Basin, Kendall R. Grazul

Dissertations, Master's Theses and Master's Reports - Open

The late Paleozoic Cutler Formation, where exposed near the modern-day town of Gateway, Colorado, has traditionally been interpreted as the product of alluvial fan deposition within the easternmost portion of the Paradox Basin. The Paradox Basin formed between the western margin of the Uncompahgre Uplift segment of the Ancestral Rocky Mountains and the western paleoshoreline of the North American portion of Pangea. The Paradox Basin region is commonly thought to have experienced semi-arid to arid conditions and warm temperatures during the Pennsylvanian and Permian. Evidence described in this paper support prior interpretations regarding paleoclimate conditions and the inferred depositional environment …

Rate Of Convergence Of Maximum Likelihood Estimators Under Relaxed Smoothness Conditions On The Likelihood Function, Brent Halonen

Dissertations, Master's Theses and Master's Reports - Open

This report reviews literature on the rate of convergence of maximum likelihood estimators and establishes a Central Limit Theorem, which yields an O(1/sqrt(n)) rate of convergence of the maximum likelihood estimator under somewhat relaxed smoothness conditions. These conditions include the existence of a one-sided derivative in θ of the pdf, compared to up to three that are classically required. A verification through simulation is included in the end of the report.

The Influence Of Diet Composition, Plant Defensive Chemicals, And Winter Severity On The Nutritional Condition Of A Freeranging, Generalist Herbivore, Grace L. Parikh

Dissertations, Master's Theses and Master's Reports - Open

Herbivory requires animals to manage intake of toxic phytochemicals. Detoxification and excretion of these chemicals prevents toxicity, but is energetically expensive. I investigated the relationship between investment in detoxification and nutritional condition for moose on Isle Royale National Park (Alces alces) during winter, using urinary indices from urine samples collected in snow. The ratio of urinary urea nitrogen:creatinine is an indicator of nutritional condition, and the ratio of glucuronic acid:creatinine is an indicator of investment in detoxification. Nutritional condition declined with greater investment in detoxification. An alternative means of managing defensive chemical intake is to diversify the diet. Microhistological …

Women, Cycling, And The Public Sphere: How Discursive And Community Practices Affect Engagement, Elsa L. Roberts

Dissertations, Master's Theses and Master's Reports - Open

This thesis considers the impact that discursive and community practices have on women’s access to the public sphere by examining female cyclists and a cycling community in Miami, Florida via interviews and observation. In the interviews, female cyclists frequently reported fears for their safety, including concern over harassment, when riding in public space. I interviewed participants of the cycling community and observed Emerge Miami’s meetings and events, where publicly organized cycling excursions were a major component. Using the theoretical and methodological lenses of Feminist Critical Discourse Analysis and Communities of Practice, I examined the interviews to understand how participants discursively …

Bayesian Change-Point Analysis In Linear Regression Model With Scale Mixtures Of Normal Distributions, Shuaimin Kang

Dissertations, Master's Theses and Master's Reports - Open

In this thesis, we consider Bayesian inference on the detection of variance change-point models with scale mixtures of normal (for short SMN) distributions. This class of distributions is symmetric and thick-tailed and includes as special cases: Gaussian, Student-t, contaminated normal, and slash distributions. The proposed models provide greater flexibility to analyze a lot of practical data, which often show heavy-tail and may not satisfy the normal assumption.

As to the Bayesian analysis, we specify some prior distributions for the unknown parameters in the variance change-point models with the SMN distributions. Due to the complexity of the joint posterior …

Sorghum Yield And Zai Holes In Goundi, Burkina Faso, Justin Gelb

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this study was to determine if there was a difference in sorghum yield between the Mossi zai hole and the Gourounsi zai hole, specifically examining the effects of manure and soil water conservation. A study field was created with six different treatments: (1) control with traditional management (no zai holes), (2) traditional management with manure, (3) Mossi zai holes with no manure, (4) Mossi zai holes with manure, (5) Gourounsi zai holes with no manure, and (6) Gourounsi zai holes with manure. Soil moisture readings were taken after each rainstorm (about weekly), soil properties were analyzed before …

A Petrophysical Evaluation Of The Trenton-Black River Formation Of The Michigan Basin, Lu Yang

Dissertations, Master's Theses and Master's Reports - Open

This work is conducted to study the geological and petrophysical features of the Trenton- Black River limestone formation. Log curves, crossplots and mineral identification methods using well-log data are used to determine the components and analyze changes in lithology. Thirty-five wells from the Michigan Basin are used to define the mineralogy of Trenton-Black River limestone. Using the different responses of a few log curves, especially gamma-ray, resistivity and neutron porosity, the formation tops for the Utica shale, the Trenton limestone, the Black River limestone and the Prairie du Chien sandstone are identified to confirm earlier authors’ work and provide a …

A Market-Based Approach To 3d Printing For Economic Development In Ghana, Wade Aitken-Palmer

Dissertations, Master's Theses and Master's Reports - Open

The purpose of this report is to create the foundation for further study of a market-based approach to 3D printing as an instrument for economic development in Ghana. The delivery of improved products and services to the most underserved markets is needed to spur economic activity and improve standards of living. The relationship between economic development and the advancement of technology is considered within the context of Ghana. An opportunity for market entry exists within both the bottom of the economic pyramid and the mid-segment market. 3D printing (additive manufacturing) has proven to be a disruptive technology that has demonstrated …

Examining Policy Capacity Initiatives Within Climate Change Frameworks In Three Us And Canadian Sectors Using Nvivo Content Analysis, Mehjabeen Rahman

Dissertations, Master's Theses and Master's Reports - Open

The climate change narrative has changed from one of mitigation to one of adaptation. Governments around the world have created climate change frameworks which address how the country can better cope with the expected and unexpected changes due to global climate change. In an effort to do so, federal governments of Canada and the United States, as well as some provinces and states within these countries, have created detailed documents which outline what steps must be taken to adapt to these changes. However, not much is mentioned about how these steps will be translated in to policy, and how that …

Writing A Community Guidebook For Evaluating Low-Grade Geothermal Energy From Flooded Underground Mines For Heating And Cooling Buildings, Edward Peace Louie

Dissertations, Master's Theses and Master's Reports - Open

When underground mines close they often fill with water from ground and surface sources; each mine can contain millions to billions of gallons of water. This water, heated by the Earth’s geothermal energy, reaches temperatures ideal for heat pumps. The sheer scale of these flooded underground mines presents a unique opportunity for large scale geothermal heat pump setups which would not be as economically, socially, and environmentally feasible anywhere else. A literature search revealed approximately 30 instances of flooded underground mines being used to heat and cool buildings worldwide. With thousands of closed/abandoned underground mines in the U.S. and a …

Flood Risk Assessment Under Historical And Predicted Land Use Change Using Continuous Hydrologic Modeling, Jonathan T. Nelson

Dissertations, Master's Theses and Master's Reports - Open

Current procedures for flood risk estimation assume flood distributions are stationary over time, meaning annual maximum flood (AMF) series are not affected by climatic variation, land use/land cover (LULC) change, or management practices. Thus, changes in LULC and climate are generally not accounted for in policy and design related to flood risk/control, and historical flood events are deemed representative of future flood risk. These assumptions need to be re-evaluated, however, as climate change and anthropogenic activities have been observed to have large impacts on flood risk in many areas. In particular, understanding the effects of LULC change is essential to …

Criteria For Sustainable Product Design With 3d Printing In The Developing World, Benjamin L. Savonen

Dissertations, Master's Theses and Master's Reports - Open

The demand for consumer goods in the developing world continues to rise as populations and economies grow. As designers, manufacturers, and consumers look for ways to address this growing demand, many are considering the possibilities of 3D printing. Due to 3D printing’s flexibility and relative mobility, it is speculated that 3D printing could help to meet the growing demands of the developing world. While the merits and challenges of distributed manufacturing with 3D printing have been presented, little work has been done to determine the types of products that would be appropriate for such manufacturing.

Inspired by the author’s two …

Optical Access Engine Setup And Validation, Jiongxun (Justin) Zhang

Dissertations, Master's Theses and Master's Reports - Open

The optical access engine integrated with the diagnostic and optical measurement techniques is a great platform for engine research because it provides clear visual access to the combustion chamber inside the engines. An optical access engine customized based on a 4-cylinder spark ignited direct injection (SIDI) production engine is located in the Advanced Power Systems Laboratories (APS LABS) at Michigan Technological University. This optical access engine inside the test cell has been set up for different engine research.

In this report, two SAE papers in engine research utilizing the optical access engine are reviewed to gain basic understanding of the …

Interactive Effects Of Climate Change And Fungal Communities On The Decomposition Of Wood-Derived Carbon In Forest Soils, Samantha L. Mosier

Dissertations, Master's Theses and Master's Reports - Open

Soils are the largest sinks of carbon in terrestrial ecosystems. Soil organic carbon is important for ecosystem balance as it supplies plants with nutrients, maintains soil structure, and helps control the exchange of CO₂ with the atmosphere. The processes in which wood carbon is stabilized and destabilized in forest soils is still not understood completely. This study attempts to measure early wood decomposition by different fungal communities (inoculation with pure colonies of brown or white rot, or the original microbial community) under various interacting treatments: wood quality (wood from +CO₂, +CO₂+O₃, or ambient …