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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 …

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 …

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 …

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 …

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 …

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 …

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 …

Design And Development Of Bodipy-Based Fluorescent Probes For Sensing And Imaging Of Cyanide, Zn (Ii) Ions, Lysosomal Ph And Cancer Cells, Jingtuo Zhang

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

BODIPY (4,4-Difluoro-3a,4a-diaza-s-indacene) dyes have gained lots of attention in application of fluorescence sensing and imaging in recent years because they possess many distinctive and desirable properties such as high extinction coefficient, narrow absorption and emission bands, high quantum yield and low photobleaching effect. However, most of BODIPY-based fluorescent probes have very poor solubilities in aqueous solution, emit less than 650 nm fluorescence that can cause cell and tissue photodamages compared with bio-desirable near infrared (650-900 nm) light. These undesirable properties extremely limit the applications of BODIPY-based fluorescent probes in sensing and imaging applications. In order to overcome these drawbacks, we …

Barium Concentrations In Rock Salt By Laser Induced Breakdown Spectroscopy, Kiley J. Spirito

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

Time-REsolved Laser Induced Breakdown Spectroscopy (TRELIBS) was used to determine the elemental concentration of barium in Texas Dome rock salt. TRELIBS allows for an efficient and in situ concentration analysis technique that detects a wide range of elements with no sample preparation.

TRELIBS measurements were made in the 545nm to 594nm wavelength range. The proximity of a strong barium emission line (553.5481 nm) to the sodium doublet (588.9950 nm and 589.5924 nm) allowed for measurement within a single frame of the spectrograph.

This barium emission line was compared to the sodium doublet for relative intensity. A homemade calibration sample containing …

Understanding Farmers’ Perceptions And The Effects Of Shea Tree Vitellaria Paradoxa Distribution In Agroforestry Parklands Of The Upper West Region, Ghana, Fahimeh Baziari

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

Agroforestry parklands represent a vast majority of the agricultural landscape under subsistent-oriented farming in semi-arid West Africa. Parklands are characterized by the growth of well- maintained trees (e.g., shea) on cultivated fields as a result of both environmental and human influences. Shea (Vitellaria paradoxa) provides a cultural and economic benefit to the local people of Ghana, especially women. Periods between traditional fallow rotation systems have reduced recently due to agricultural development and a demand for higher production. As a result, shea trees, which regenerate during fallow periods, has decreased over the landscape. The aim of this study was …

Evaluating The Oil Sands Reclamation Process: Assessing Policy Capacity And Stakeholder Access For Government And Non-Governmental Organizations Operating In Alberta’S Oil Sands, Tyler Patterson

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

By employing interpretive policy analysis this thesis aims to assess, measure, and explain policy capacity for government and non-government organizations involved in reclaiming Alberta's oil sands. Using this type of analysis to assess policy capacity is a novel approach for understanding reclamation policy; and therefore, this research will provide a unique contribution to the literature surrounding reclamation policy. The oil sands region in northeast Alberta, Canada is an area of interest for a few reasons; primarily because of the vast reserves of bitumen and the environmental cost associated with developing this resource. An increase in global oil demand has established …

Multiscale Examination And Modeling Of Electron Transport In Nanoscale Materials And Devices, Douglas R. Banyai

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

For half a century the integrated circuits (ICs) that make up the heart of electronic devices have been steadily improving by shrinking at an exponential rate. However, as the current crop of ICs get smaller and the insulating layers involved become thinner, electrons leak through due to quantum mechanical tunneling. This is one of several issues which will bring an end to this incredible streak of exponential improvement of this type of transistor device, after which future improvements will have to come from employing fundamentally different transistor architecture rather than fine tuning and miniaturizing the metal-oxide-semiconductor field effect transistors (MOSFETs) …

Exploration Of The Mtsat2 Satellite Capabilities For Real Time Detection And Characterization Of Volcanic Emissions, Nicholas R. Stewart

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

In this report, we attempt to define the capabilities of the infrared satellite remote sensor, Multifunctional Transport Satellite-2 (MTSAT-2) (i.e. a geosynchronous instrument), in characterizing volcanic eruptive behavior in the highly active region of Indonesia. Sulfur dioxide data from NASA's Ozone Monitoring Instrument (OMI) (i.e. a polar orbiting instrument) are presented here for validation of the processes interpreted using the thermal infrared datasets. Data provided from two case studies are analyzed specifically for eruptive products producing large thermal anomalies (i.e. lava flows, lava domes, etc.), volcanic ash and SO₂ clouds; three distinctly characteristic and abundant volcanic emissions. Two primary …

Generating Plans In Concurrent, Probabilistic, Over-Subscribed Domains, Li Li

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

Planning in realistic domains typically involves reasoning under uncertainty, operating under time and resource constraints, and finding the optimal subset of goals to work on. Creating optimal plans that consider all of these features is a computationally complex, challenging problem. This dissertation develops an AO* search based planner named CPOAO* (Concurrent, Probabilistic, Over-subscription AO*) which incorporates durative actions, time and resource constraints, concurrent execution, over-subscribed goals, and probabilistic actions. To handle concurrent actions, action combinations rather than individual actions are taken as plan steps. Plan optimization is explored by adding two novel aspects to plans. First, parallel steps that serve …

Object-Based Classification Of Earthquake Damage From High-Resolution Optical Imagery Using Machine Learning, James Bialas

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

Object-based approaches to the segmentation and supervised classification of remotely-sensed images yield more promising results compared to traditional pixel-based approaches. However, the development of an object-based approach presents challenges in terms of algorithm selection and parameter tuning. Subjective methods and trial and error are often used, but time consuming and yield less than optimal results. Objective methods are warranted, especially for rapid deployment in time sensitive applications such as earthquake induced damage assessment.

Our research takes a systematic approach to evaluating object-based image segmentation and machine learning algorithms for the classification of earthquake damage in remotely-sensed imagery using Trimble’s eCognition …

Automated Scour Detection Arrays Using Bio-Inspired Magnetostrictive Flow Sensors, Baibhav Rajbhandari

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

Scour is the most common cause of catastrophic bridge failures worldwide. Approximately over 60% of bridge failures reported in the United States from 1966 to 2005 are scour related. To ensure the continued safe operation of bridges, monitoring bridge scour is of paramount importance. Most monitoring regimes that are widely used are based on expensive underwater instrumentation. This research focuses on scour detection using automated remote flow detection arrays based on bio-inspired flow sensors. This study employs an array of bio inspired flow sensors that are inexpensive and robust versions of buried-rod scour sensor arrays, coupled with low-power wireless sensor …

Understanding Electronic Structure And Transport Properties In Nanoscale Junctions, Kamal B. Dhungana

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

Understanding the electronic structure and the transport properties of nanoscale materials are pivotal for designing future nano-scale electronic devices. Nanoscale materials could be individual or groups of molecules, nanotubes, semiconducting quantum dots, and biomolecules. Among these several alternatives, organic molecules are very promising and the field of molecular electronics has progressed significantly over the past few decades. Despite these progresses, it has not yet been possible to achieve atomic level control at the metal-molecule interface during a conductance measurement, which hinders the progress in this field. The lack of atomic level information of the interface also makes it much harder …

Biogeochemical Cycling In Lake Superior Tributaries: Seasonality, Quantity And Quality Of Export, Ashley Anne Coble

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

Seasonal and spatial variability in environmental factors may affect dissolved organic matter composition and nutrient transformation and retention in streams. The objective of this research was to quantify and describe seasonality, quantity, and quality of nutrient processing and export of ammonium (NH₄), soluble reactive phosphate (SRP), and dissolved organic carbon (DOC) into Lake Superior through intensive study in a small 1st order watershed coupled with snapshot measurements across 12 tributaries that varied in size, location, and wetland coverage. Our results suggest biodegradable C is exported from a small headwater stream year-round and that DOC mineralization rates can be …

Evaluating The Potential For Passive Greywater Irrigation In Northern Ghana, Chelsea L. Fagan

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

Water scarcity, malaria, and malnutrition are all concerns facing the people of Chirifoyili and the Northern Region of Ghana. Greywater pooling outside of homes increases human exposure to pathogens and provides breeding grounds for disease carrying insects, especially malaria spreading mosquitoes. This project looks at draining this water away from the home and using it to irrigate vegetables, fruit trees and other beneficial plants.

The purpose of this study is to estimate the effects of greywater irrigation on the growth of plants commonly found in village home gardens. The field project consisted of constructing and managing household greywater irrigation systems …

Finite Volume Methods For Linear Partial Differential Equations With Delta-Singularities, Nattaporn Chuenjarern

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

In this work, we study hyperbolic conservation law in one space dimension with δ-singularities as the initial data. We use finite volume methods to find the sizes of pollution region. Firstly, we study finite volume method (FVM) with linear weights and weighted essentially non-oscillatory (WENO) scheme and apply both methods to linear partial differential equations without singularities to check the accuracy. Then we use both methods to find the numerical solutions and compute errors of linear equations with δ-singularities. Lastly, we use such results to find the size of pollution region of each method. These results show that …

A Case Study Of Data In The Management Of Water Resources In The Gunnison River Basin, Colorado, Rhianna L. Williams

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

In the American Southwest, a growing population combined with climate change induced weather pattern changes are creating growing conflict for uses of the over appropriated Colorado River System. Water managers use a variety of tools and data to make decisions at the local and regional level which will impact access for future users. The purpose of this study is to understand how water managers use data and knowledge to manage current and future access to water resources in a water scarce region. A case study of the Gunnison River Basin located within the larger Colorado River Basin was conducted over …

Study Of Non-Reciprocal Dichroism In Photonic Structures, Anindya Majumdar

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

Non-reciprocal phenomena are widely used in photonic devices. Important applications such as isolators and circulator waveguide structures depend on non-reciprocal effects. The basis of these phenomena is a difference in phase or refractive index for an electromagnetic wave of a given polarization as it travels through a medium in opposite directions. Generally this applies to the real part of the refractive index. The present report addresses a less studied phenomenon in non-reciprocal propagation, namely differences in optical absorption loss for a given polarization state in opposite propagation directions, a phenomenon we have termed non-reciprocal dichroism. Nonreciprocal dichroism can be defined …

Household Biosand Water Filters: Materials, Capacity, And Temperature Effects On Performance, Nathan B. Arnold

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

The household biosand filter (BSF) is one of the world’s most utilized point-of-use (POU) water treatment tools where drinking water is not reliably potable. The feasibility of using ferrocement for construction, the filter volume, and the effect of temperature on removal are unclear, however. The following field and laboratory research was carried out in Panama and at Michigan Technological University. Field testing of ferrocement biosand filters (FBSFs) in rural Panama yielded average coliform and E.coli removals that compared favorably to plastic and cement BSFs. Parallel testing of a larger-bodied FBSF and a conventionally-sized BSF revealed that the former is necessary …

Application Of A Hazard Rating System For Rock Slopes Along A Transportation Corridor Using Remote Sensing, Samantha M. Justice

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

Rockfall hazards are a significant and ongoing threat to infrastructure located within steep terrain. Assessing the relative hazard along a transportation corridor is important in determining the likely location and mode of rock slope failure. Understanding where to focus attention and funds is vital for the infrastructure agencies because of the high cost of implementing preventative measures for long lengths of infrastructure. Hazard analysis has historically relied upon experienced field engineers assessing each site, which is not time or cost effective. This study focuses on using remote sensing techniques to analyze rock slopes along transportation corridors. A case study from …