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Improved Sensitivity Of Resonant Mass Sensor Based On Micro Tilting Plate And Micro Cantilever, Xiaoyu Song

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

Vapor sensors have been used for many years. Their applications range from detection of toxic gases and dangerous chemicals in industrial environments, the monitoring of landmines and other explosives, to the monitoring of atmospheric conditions. Microelectrical mechanical systems (MEMS) fabrication technologies provide a way to fabricate sensitive devices. One type of MEMS vapor sensors is based on mass changing detection and the sensors have a functional chemical coating for absorbing the chemical vapor of interest. The principle of the resonant mass sensor is that the resonant frequency will experience a large change due to a small mass of gas vapor …

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 …

An Energy Based Minimum-Time Optimal Control Of Dc-Dc Converters, Amir Zandnia

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

Time-optimal response is an important and sometimes necessary characteristic of dynamic systems for specific applications. Power converters are widely used in different electrical systems and their dynamic response will affect the whole system. In many electrical systems like microgrids or voltage regulators which supplies sensitive loads fast dynamic response is a must. Minimum time is the fastest converter to compensate the step output reference or load change. Boost converters as one of the wildly used power converters in the electrical systems are aimed to be controlled in optimal time in this study. Linear controllers are not able to provide the …

Water Use And System Reliability Under Dieselgenerator And Solar Photovoltaic Powered Pumping Systems: A Case Study Of Solla Togo, Alicia R. Sherrin

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

Access to improved potable water sources is recognized as one of the key factors in improving health and alleviating global poverty. In recently years, substantial investments have been made internationally in potable water infrastructure projects, allowing 2.3 billion people to gain access to potable water from 1990-2012. One such project was planned and installed in Solla, Togo, a rural village in the northern part of the country, from 2010-2012. Ethnographic studies revealed that, while the community has access to potable water, an estimated 45% of the village’s 1500 residents still rely on unprotected sources for drinking and cooking. Additionally, inequality …

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 …

A Naturalistic Computational Model Of Human Behavior In Navigation And Search Tasks, Brandon S. Perelman

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

Planning, navigation, and search are fundamental human cognitive abilities central to spatial problem solving in search and rescue, law enforcement, and military operations. Despite a wealth of literature concerning naturalistic spatial problem solving in animals, literature on naturalistic spatial problem solving in humans is comparatively lacking and generally conducted by separate camps among which there is little crosstalk. Addressing this deficiency will allow us to predict spatial decision making in operational environments, and understand the factors leading to those decisions. The present dissertation is comprised of two related efforts, (1) a set of empirical research studies intended to identify characteristics …

Instantaneous Photosynthetic Response To Temperature Of Mature Forest Canopies And Experimentally Warmed Seedlings, Alida C. Mau

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

Tropical trees have been shown to be more susceptible to warming compared to temperate species, and have shown growth and photosynthetic declines at elevated temperatures as little as 3oC above ambient. However, regional and global vegetation models lack the data needed to accurately represent physiological response to increased temperatures in tropical forests. We compared the instantaneous photosynthetic responses to elevated temperatures of four mature tropical rainforest tree species in Puerto Rico and the temperate broadleaf species sugar maple (Acer saccharum) in Michigan. Contrary to expectations, leaves in the upper canopy of both temperate and tropical forests had temperature …

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 …

The Hydrosocial Costs Of High-Volume Hydraulic Fracturing: A Tale Of Two Counties In Michigan, Amanda Kreuze

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

Although natural gas has been praised as a clean and abundant energy source, the varying impacts and uncertainties surrounding the process of extracting natural gas from unconventional sources, known as horizontal high-volume hydraulic fracturing (HVHF) or “fracking,” have raised important concerns. The practice of HVHF is expanding so quickly that the full impacts are not yet known. This thesis project, using a grounded theory methodological approach, explores the risks and benefits associated with HVHF as recognized by the residents of two Michigan counties, one that currently produces natural gas by HVHF (Crawford County) and one that does not (Barry County). …

Translocation And Telemetry Tracking Of Lake Sturgeon In The Menominee River, Mi / Wi, Jeremy G. Olach

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

The Menominee River is a Michigan-Wisconsin boundary water historically traversed by lake sturgeon (Acipenser fulvescens), but now contains fragmented populations between hydroelectric dams. Though fish passage is currently being implemented on the lower dams, it is unclear whether sturgeon given access to historic spawning grounds would use them. In 2012 and 2013, a total of 15 pre-spawning sturgeon were captured, implanted with sonic transmitters and translocated upstream over two hydroelectric dams to the stretch below the historic spawning site of Sturgeon Falls. Sturgeon were then tracked via five stationary receivers from April 2012 until August 2013, and with …

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 …

Molecular Modeling Of Epon 862-Detda / Carbon Composites, Cameron Hadden

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

The thermoset epoxy resin EPON 862, coupled with the DETDA hardening agent, are utilized as the polymer matrix component in many graphite (carbon fiber) composites. Because it is difficult to experimentally characterize the interfacial region, computational molecular modeling is a necessary tool for understanding the influence of the interfacial molecular structure on bulk-level material properties. The purpose of this research is to investigate the many possible variables that may influence the interfacial structure and the effect they will have on the mechanical behavior of the bulk level composite. Molecular models are established for EPON 862-DETDA polymer in the presence of …

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 …

The Fanned Flames Of Discontent: A Solidarity-Inspired History Of The Identity/Ideology, Cultural History, And Rhetorical Strategies Of The Wobblies During The 1916 Minnesota Iron Ore Strike, Gary Kaunonen

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

Rooted in critical scholarship this dissertation is an interdisciplinary study, which contends that having a history is a basic human right. Advocating a newly conceived and termed, Solidarity-inspired History framework/practice perspective, the dissertation argues for and then delivers a restorative voice to working-class historical actors during the 1916 Minnesota Iron Ore Strike. Utilizing an interdisciplinary methodological framework the dissertation combines research methods from the Humanities and the Social Sciences to form a working-class history that is a corrective to standardized studies of labor in the late 19th and early 20th centuries. Oftentimes class interests and power relationships determine the dominant …

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 …

The Dispersion And Selective Flocculation Of Hematite Ore, Howard James Haselhuhn Iii

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

Iron ore is one of the most important ores in the world. Over the past century, most mining of iron ore has been focused on magnetite (Fe3O4). As the name suggests, magnetite is magnetic in nature and is easily separated from gangue (unwanted) minerals through magnetic separation processes. Unfortunately, the magnetite ore bodies are diminishing. Because of this, there has been a recent drive to pursue technology that can economically separate hematite (Fe2O3) from its gangue minerals as hematite is a much more abundant source of iron. Most hematite ore has a very small liberation size that is frequently less …

Net Asset Valuation Of Whiting Petroleum’S Acquisition Of Kodiak Oil And Gas, Alexander M. Beeker

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

In July 2014, it was announced that Whiting Petroleum would acquire Kodiak Oil & Gas in an all-stock deal valued at $6 billion. Both companies are headquartered in Denver and operate primarily in the Bakken but in a deal of this size it is possible for executives to hold ulterior motives for mergers such as higher compensation and golden parachutes. Acceptable motivating factors for engaging in a merger include cost savings through synergies and economies of scale, increased market power, asset diversification, and price volatility. A net asset valuation was used to help determine if shareholders should vote in favor …

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 …

Mechanical Impedance Of Ankle As A Function Of Electromyography Signals Of Lower Leg Muscles Using Artificial Neural Network, Chen Jia

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

This paper reports on the feasibility of developing a model to describe the nonlinear relationship between the mechanical impedance of the human ankle within a specified range of frequency and the root mean square (RMS) value of the Electromyography (EMG) signals of the muscles of human ankle using Artificial Neural Network (ANN). A lower extremity rehabilitation robot — Anklebot was used to apply pseudo-random mechanical perturbations to the ankle and measure the angular displacement of the ankle to estimate the data of ankle mechanical impedance. Meanwhile, the surface EMG signals from the selected muscles were monitored and recorded using a …

Modeling And Analysis Of Reactivity Controlled Compression Ignition (Rcci) Combustion, Mohammadreza Nazemi

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

Homogeneous Charge Compression Ignition (HCCI) and Premixed Charge Compression Ignition (PCCI) combustion strategies are promising methods for achieving low engine-out NOx and soot emissions as well as high indicated efficiency. However, these combustion strategies have difficulties with controlling the rate of heat release and lack of an adequate combustion phasing control mechanism. A dual-fuel Reactivity Controlled Compression Ignition (RCCI) combustion strategy will address these issues due to the existence of precise means for controlling the heat release rate and combustion phasing. In the RCCI strategy two fuels with different reactivity (auto-ignition characteristics, e.g., gasoline and diesel) are blended inside the …

Low Impact Development (Lid) Opportunities In The District Of Lamúd, Perú: A Study Of Hydrology, Costs And Maintenance Of Appropriate Stormwater Best Management Practices (Bmps), Olga M. Cano

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

The study aims at identifying opportunities to implement Low Impact Development (LID) Best Management Practices (BMPs) for stormwater management, in the District of Lámud, Perú. Other studies have noted the importance of appropriate stormwater management as part of urban development in developing countries.

Environmental, economic and social aspects were analyzed to identify the most appropriate case. Stormwater Management Model (SWMM) 5.1, was used to obtain runoff results. Ten case scenarios were set up with LID BMP combinations of infiltration trenches, vegetated swales, and retention ponds. Water Environment Research Foundation (WERF) life cost models were used as a reference to calculate …

Engaging Metis: Exploring An African Woman's Negotiation Of Change, Ruby Pappoe

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

African women’s emerging visibility as social and political actors has received a lot of attention in the past two decades. Scholars have explored women’s political movements and sociocultural activism from various perspectives to expose their contributions to social change. Although this scholarship has expanded to incorporate multiple voices as well as expose the contemporary strategies of resistance women engage in to overcome difficult challenges, there seems to be little research on ordinary women as they also confront their daily challenges in hope of improving their situations. This research takes up this gap by exploring a Ghanaian woman’s resistance in the …

Pose Estimation And 3d Reconstruction Using Sensor Fusion, Anuj S. Potnis

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

A camera maps 3-dimensional (3D) world space to a 2-dimensional (2D) image space. In the process it loses the depth information, i.e., the distance from the camera focal point to the imaged objects. It is impossible to recover this information from a single image. However, by using two or more images from different viewing angles this information can be recovered, which in turn can be used to obtain the pose (position and orientation) of the camera. Using this pose, a 3D reconstruction of imaged objects in the world can be computed. Numerous algorithms have been proposed and implemented to solve …

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 …

Development And Validation Of A Radtherm Model To Predict Exhaust System Behavior For A Hybrid Xm1124 Hmmwv, Souman Haldar

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

Accurately predicting component temperatures, and the influence various subsystems have on each other prior to hardware development and testing is an important aspect of the vehicle development process. In this report, a 1-D thermal model is used for predicting the behavior of the exhaust system and underbody area of prototype Hybrid Electric HMMWV XM1124. This prototype vehicle is designed to be capable of exporting up to 15 kW of electrical power to a micro-grid or similar operation. However, in this project instead of exporting power to a micro-grid, 6.5 kW of power was used to charge the batteries and increase …

Structure And Agency In Organizational Contexts Of Women In Stem, Sidouane Patcha Lum

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

This research explores the extant literature on socio-cultural and institutional structures in STEM which accounts for women’s under-representation in these fields. It questions eight women in STEM’s awareness of these structures via interview sessions, and examines how they ‘negotiate’ their identities to thrive in ‘male-dominated’ fields. Participants’ awareness and shared experiences of these structures reflects an evolving society still ingrained in gender stereotypes that work to the detriment of women in STEM. In order to make meaning out this data, I apply standpoint theory to get into these women’s lives and explore the testable conclusions of traditional assumptions related to …

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 …

Electrochemical Processes In Microfluidics Systems Under Ac Electric Fields, Ran An

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

Alternating current (AC) electric signal has been widely applied in microfluidic systems to induce AC electrokinetic behavior. AC electrokinetic phenomena including AC electrophoresis, AC dielectrophoresis, AC electroosmosis flow and AC electrothermal flow are widely applied in (bio)particle sorting, separation and concentration and micropumps. However, numbers of non-ideal AC electrokinetic behaviors have been reported: human erythrocyte deformation in AC dielectrophoresis system has been observed; flow reversal in AC electroosmosis flow pumps has also been reported. In this dissertation, a systematic study on human erythrocyte crenation in AC dielectrophoresis system was firstly conducted. Multiple possible physical mechanisms inducing cell crenation including temperature, …