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2024

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The Integration Of Neuromorphic Computing In Autonomous Robotic Systems, Md Abu Bakr Siddique Jan 2024

The Integration Of Neuromorphic Computing In Autonomous Robotic Systems, Md Abu Bakr Siddique

Dissertations, Master's Theses and Master's Reports

Deep Neural Networks (DNNs) have come a long way in many cognitive tasks by training on large, labeled datasets. However, this method has problems in places with limited data and energy, like when planetary robots are used or when edge computing is used [1]. In contrast to this data-heavy approach, animals demonstrate an innate ability to learn by communicating with their environment and forming associative memories among events and entities, a process known as associative learning [2-4]. For instance, rats in a T-maze learn to associate different stimuli with outcomes through exploration without needing labeled data [5]. This learning paradigm …


Exploring Usability In Exercise Interventions: From Conceptualization To Measurement And Application, Anne Inger Mørtvedt Jan 2024

Exploring Usability In Exercise Interventions: From Conceptualization To Measurement And Application, Anne Inger Mørtvedt

Dissertations, Master's Theses and Master's Reports

Exercise interventions hold promise for preventing and treating numerous conditions, diseases, and injuries. However, these interventions will only be effective if they are being used. Unfortunately, uptake and adherence to prescribed exercise and physical activity guidelines are insufficient. Some reasons for this include lack of knowledge, resources, flexibility, and enjoyment. Exercise program developers need to not only consider the effectiveness of the program during the development phase, but also involve end-users and receive feedback on program usability to determine likelihood of uptake and adoption. Usability testing can be used to detect barriers to use and implementation likelihood but has not …


Discontinuous Galerkin Methods For Compressible Miscible Displacements And Applications In Reservoir Simulation, Yue Kang Jan 2024

Discontinuous Galerkin Methods For Compressible Miscible Displacements And Applications In Reservoir Simulation, Yue Kang

Dissertations, Master's Theses and Master's Reports

This dissertation contains research on discontinuous Galerkin (DG) methods applied to the system of compressible miscible displacements, which is widely adopted to model surfactant flooding in enhanced oil recovery (EOR) techniques. In most scenarios, DG methods can effectively simulate problems in miscible displacements.
However, if the problem setting is complex, the oscillations in the numerical results can be detrimental, with severe overshoots leading to nonphysical numerical approximations. The first way to address this issue is to apply the bound-preserving
technique. Therefore, we adopt a bound-preserving Discontinuous Galerkin method
with a Second-order Implicit Pressure Explicit Concentration (SIPEC) time marching
method to …


Integrating Arcgis And Redux Using Middleware, Vishnu Vardhan Reddy Rapuru Jan 2024

Integrating Arcgis And Redux Using Middleware, Vishnu Vardhan Reddy Rapuru

Dissertations, Master's Theses and Master's Reports

The integration of ArcGIS with Redux through middleware presents a novel approach to managing state in geospatial applications. This report outlines the process and benefits of combining ArcGIS’s robust mapping and analytics capabilities with Redux’s predictable state container for JavaScript apps. It begins with an introduction to both technologies, followed by a detailed discussion on the architecture design, focusing on the role of middleware as the linchpin in this integration[1]. The paper highlights the benefits, such as improved state management and application performance, and addresses the challenges encountered during the integration process. Implementation details are provided, including the setup of …


Optimizing Php Api Calls With Pagination And Caching, Parsharam Reddy Sudda Jan 2024

Optimizing Php Api Calls With Pagination And Caching, Parsharam Reddy Sudda

Dissertations, Master's Theses and Master's Reports

The Keweenaw Time Traveler (KeTT) project is devoted to mapping the historical and social landscapes of the Keweenaw Peninsula. During the project, it was discovered that the server-side performance needed improvement. To address this issue, the "Optimizing PHP API Calls with Pagination and Caching" initiative was launched. This initiative focused on refining API calls, implementing server caching and pagination, and fortifying security against common vulnerabilities. The project successfully mitigated risks associated with SQL Injection and XSS through meticulous code enhancements while improving error handling. Additionally, the introduction of Scroll-Induced Pagination optimized data delivery, significantly reducing response times, and elevating the …


Gis-Based Landscape Prioritization To Guide Invasive Species Survey, Erin R. Mauk Jan 2024

Gis-Based Landscape Prioritization To Guide Invasive Species Survey, Erin R. Mauk

Dissertations, Master's Theses and Master's Reports

Utilizing prioritization models gives invasive species managers the capability to systematically target surveying and management toward priority areas, therefore maximizing limited financial resources by increasing the value that management can have on the landscape. In this report, Geographic Information System (GIS) techniques were utilized to produce an invasion risk model and a quality land model. Combining these two models produced a landscape-level prioritization model, which denoted the land quality and associated invasion risk across the study area. High-quality land was commonly distributed within Isle Royale National Park, along Lake Superior’s coastline, and within coastal wetlands and riparian habitats. Areas of …


Matrix Stiffness Sensing By Nascent Adhesions And The Role Of Riam In Adhesion Assembly, Nikhil Mittal Jan 2024

Matrix Stiffness Sensing By Nascent Adhesions And The Role Of Riam In Adhesion Assembly, Nikhil Mittal

Dissertations, Master's Theses and Master's Reports

Mechanical stiffness of the extracellular matrix (ECM) impacts many cellular functions such as proliferation, migration, and differentiation. ECM stiffness is sensed by a cell via integrin-based focal adhesions (FAs) by changing conformation and biochemical activities of molecules within FAs by the exchange of the force between the ECM and filamentous actin (F-actin). Cells in turn respond to this stiffness by generating traction force that plays an important role in many biological events such as tissue morphogenesis, stem cell differentiation, wound healing, and cancer cell metastasis. The stiffness of the extracellular matrix induces differential tension within integrin-based adhesions. Understanding stiffness sensing …


Anomaly Mapping Of Heavy And Light Rare Earth Elements In Central Upper Peninsula Of Michigan Using Geostatistics And Fractal Analysis, Sunday Joseph Jan 2024

Anomaly Mapping Of Heavy And Light Rare Earth Elements In Central Upper Peninsula Of Michigan Using Geostatistics And Fractal Analysis, Sunday Joseph

Dissertations, Master's Theses and Master's Reports

Rare earth elements (REEs) have gained significant global importance due to their critical role in supporting the transition towards reduced carbon emissions through industrial applications. REEs serve as essential raw materials for various critical components in modern infrastructure, defense systems, and technological advancements. Geochemical and geophysical data are pivotal in assessing the potential of REEs. Geochemical data provide direct insights into the elemental composition of rocks and soils, offering valuable information on the potential presence and dispersion of REEs. However, the complex geological processes that influence the distribution of REEs often exhibit intricate spatial patterns that may not be fully …


Study Of Particle Accelerators In The Universe With The Hawc Observatory, Rishi Babu Jan 2024

Study Of Particle Accelerators In The Universe With The Hawc Observatory, Rishi Babu

Dissertations, Master's Theses and Master's Reports

HESS J1809-193 is an unidentified TeV source discovered in 2007 by the High Energy Stereoscopic System(H.E.S.S.) Collaboration. The emission originates in a region that is rich in cosmic-ray accelerators, including several supernova remnants and pulsars, including SNR G11.1+0.1, SNR G11.0-0.0, and the young radio pulsar PSR J1809-1917. Originally classified as a pulsar wind nebula candidate, recent studies show the peak of the TeV region overlapping with a system of molecular clouds and revising the original classification for other scenarios, including a pure hadronic scenario. This dissertation presents the morphological and spectral study of HESS J1809-193 using 2139 days of data …


Developing Robust Autonomous Vehicles With Ros, Dylan J. Kangas Jan 2024

Developing Robust Autonomous Vehicles With Ros, Dylan J. Kangas

Dissertations, Master's Theses and Master's Reports

The demand for autonomous vehicles (AVs) is rising across both military and civilian sectors. These unmanned systems offer numerous advantages, such as improved efficiency, safety, and adaptability. Addressing this demand requires the development of resilient and versatile autonomous vehicles crucial for the transport and reconnaissance markets.

The sensory perception of autonomous vehicles of any kind is paramount to their ability to navigate and localize in their environment. Factors such as sensor noise, erroneous readings, and deliberate attacks should all be considered when developing a robust autonomous system. This work aims to quantify the degradation of sensor data which causes mapping …


Anaerobic Reductive Bioleaching Of Manganese Ores, Neha Sharma Jan 2024

Anaerobic Reductive Bioleaching Of Manganese Ores, Neha Sharma

Dissertations, Master's Theses and Master's Reports

Manganese extraction by biological methods is a green and economical way to produce manganese from low as well as high grade manganese ores. This is especially important for US ores, which are primarily either small in extent, low-grade with a high iron content, or both. They are therefore not suitable for conventional mining, which is very capital-intensive and requires a large up-front investment and are therefore imported at high costs. The goal is therefore to develop a process that can be applied at small scales, with minimal startup costs, and low equipment and labor requirements. It is also critical to …


Wave Energy Converter Wave Force Prediction Using A Neural Network, Morgan Kline Jan 2024

Wave Energy Converter Wave Force Prediction Using A Neural Network, Morgan Kline

Dissertations, Master's Theses and Master's Reports

Due to the unpredictable nature of large bodies of water, wave energy can be a difficult renewable resource to rely on. One way to make Wave Energy Converters (WECs) more efficient is to apply a control strategy. In many control solutions, it is assumed that the wave excitation force is known into the future. In many instances, especially with complex waveforms, this is simply not the case. Simulation studies have shown the promise of wave force prediction using neural networks. This study demonstrates this experimentally and aims to characterize the important factors when designing such a network. Several wave elevation …


Assessing The Nutritional Quality And Fate Of Saginaw Bay Dreissenid Mussel Veligers, Mitch R. Kehne Jan 2024

Assessing The Nutritional Quality And Fate Of Saginaw Bay Dreissenid Mussel Veligers, Mitch R. Kehne

Dissertations, Master's Theses and Master's Reports

The introduction and establishment of dreissenid species including zebra (Dreissena polymorpha) and quagga (D. bugensis) mussels into the Laurentian Great Lakes has resulted in significant biological and ecological change over the past 30 years. Much of the current research completed to date on understanding dreissenid mussel impacts in the Great Lakes has primarily focused on the adult life stages with less known about the larval veliger form. The goals of this thesis were to; i) investigate veliger energy densities and fatty acid profiles to compare and contrast these nutritional metrics against pelagic zooplankton and; ii) determine …


Assessing Tropical Mammal Diversity And Distribution Using Noninvasive Methods, Tiff L. Degroot Jan 2024

Assessing Tropical Mammal Diversity And Distribution Using Noninvasive Methods, Tiff L. Degroot

Dissertations, Master's Theses and Master's Reports

Central African tropical forests are rich in biodiversity and home to some of Earth’s most threatened mammals. However, mammals in the region are under increasing threat from habitat loss and degradation, coupled with an increased demand for wild meat. To conserve mammals, wildlife managers and community-led conservation efforts must understand the distribution and diversity of mammal communities. However, funding and logistical challenges make contemporary survey methods, e.g. ground surveys, difficult and expensive. Noninvasive methods allow efficient mammal diversity surveys with minimal field effort. Here, we use camera trapping and invertebrate-derived environmental DNA (“iDNA”) to assess mammal diversity and distribution in …


Epi- And Genomic Assessments Of Stamp Sand Toxicity And Population Structure Of Lake Superior Lake Trout (Salvelinus Namaycush) And Whitefish (Coregonus Clupeaformis), John C. Mccall Jan 2024

Epi- And Genomic Assessments Of Stamp Sand Toxicity And Population Structure Of Lake Superior Lake Trout (Salvelinus Namaycush) And Whitefish (Coregonus Clupeaformis), John C. Mccall

Dissertations, Master's Theses and Master's Reports

Native Lake Superior salmonid conservation is a notable success, as the only Great Lake with stable lake trout (LT) and whitefish fisheries (LWF). To quantify toxicity to LT and LWF from legacy pollution by mine tailings at Buffalo Reef in the Keweenaw Peninsula and assess their genetic structure across U.S. waters, I used reduced representation bisulfite sequencing and genotyped ~750 fishes from Buffalo Reef and Lake Superior. ~200-300 epigenetic marks in Buffalo Reef LT and LWF indicated dysregulation of pathways related to DNA damage, immune response, stress, and metabolism, relative to Lake Huron and Michigan outgroups. Population genomic analyses showed …


Modeling Of Inverter-Based Resources For Hardware In The Loop Testing Of Protection And Control Schemes, Md Aamir Rahmani Jan 2024

Modeling Of Inverter-Based Resources For Hardware In The Loop Testing Of Protection And Control Schemes, Md Aamir Rahmani

Dissertations, Master's Theses and Master's Reports

High penetration of inverter-based resources (IBR) may cause the misoperation of protective relays due to the dynamic nature of fault currents fed by the IBR during short-circuit faults. Misoperation may cause damage to power system equipment and affect the reliability of the power system. This dissertation presents an in-depth investigation into the modeling of IBR in the context of transmission line fault scenarios to understand and analyze the characteristics of fault currents fed by the IBR. The research objectives encompass the development of reliable IBR models capable of accurately replicating fault current behaviors, designing IBR operation control schemes, and implementing …


Recovering Access Control Via Disk Forensics On Low-Level Flash Memory, Caleb J. Rother Jan 2024

Recovering Access Control Via Disk Forensics On Low-Level Flash Memory, Caleb J. Rother

Dissertations, Master's Theses and Master's Reports

In the history of access control, nearly every system designed has relied on the operating system (OS) to enforce the access control protocols. However, if the OS (and specifically root access) is compromised, there are few if any solutions that can get users back into their system efficiently. In this work, we have proposed a novel approach that allows secure and efficient rollback of file access control after an adversary compromises the OS and corrupts the access control metadata. Our key observation is that the underlying flash memory typically performs out-of-place updates. Taking advantage of this unique feature, we can …


Novel Analytical Approaches For The Study Of Energy And Nutrient Flow In Streams, Michelle Catherine Kelly Jan 2024

Novel Analytical Approaches For The Study Of Energy And Nutrient Flow In Streams, Michelle Catherine Kelly

Dissertations, Master's Theses and Master's Reports

This dissertation applied novel modeling, experimental and statistical approaches to overcome the challenges of measuring and analyzing energy and nutrient cycling in streams through 3 studies: (1) determining the predictors of respiration and denitrification in streams across the United States, (2) simultaneous estimation of denitrification and nitrogen (N) fixation rates, and (3) the impact of C lability metrics on the interpretation of C degradation in DOM incubation experiments. In the first study, I used predictive modeling approaches to show that respiration and denitrification were positively correlated across the landscape but were predicted by factors at different spatial scales. Denitrification rates …


The Effects Of Experimental Warming On Root Respiration And The Fungal Community Of Tropical Forest Soil, Malik A. Sankofa Jan 2024

The Effects Of Experimental Warming On Root Respiration And The Fungal Community Of Tropical Forest Soil, Malik A. Sankofa

Dissertations, Master's Theses and Master's Reports

Climate induced changes in tropical forests fungal communities could impact diversity and abundance, forest health, and carbon release/sequestration. Under warmer soil temperatures and over time, we hypothesized that arbuscular mycorrhizal, pathogen, saprotroph diversity and abundance would increase, that ectomycorrhizal and overall fungal diversity and abundance would decrease, and that root respiration would be unaffected. Experimental warming (+2-3 ℃) was conducted on root ingrowth cores at the Tropical Responses to Altered Climate Experiment (TRACE) in Puerto Rico. ITS2 metabarcoding was used to analyze fungal diversity and abundance in control or warmed root/soil samples. We found that warming decreased arbuscular mycorrhizal diversity, …


New Method For Computing The Euclidean Condition Number With Rim-C, Cody Mccarthy Jan 2024

New Method For Computing The Euclidean Condition Number With Rim-C, Cody Mccarthy

Dissertations, Master's Theses and Master's Reports

The condition number, being critical to solving linear systems, has many impor-
tant applications. Specifically for robust control analysis, the Euclidean norm has
widespread use over the 1-norm and ∞-norm such as determining a control system’s
stability to uncertainty [1]. Much work has been done with estimating the Euclidean
condition number, but current algorithms for computing said condition number, with
large matrices, tend to run slow as well as requiring a large amount of computa-
tional resources. This report seeks to provide a more time efficient algorithm that
utilizes MATLAB’s eigs, svds, and normest commands as well as the recently …


Recognition, Subject Formation, And Agency: Marginalization And Agency In Feminist Dystopian Narratives, Samantha J. Quade Jan 2024

Recognition, Subject Formation, And Agency: Marginalization And Agency In Feminist Dystopian Narratives, Samantha J. Quade

Dissertations, Master's Theses and Master's Reports

Though more frequently discussed in regard to freedom and intersubjectivity, subject formation and recognition have significant potential in helping us understand the structures of power, domination, and resistance in our lived experiences. Through the portrayal of recognition within literature - particularly within feminist dystopian literature - we can see significant examples of not only recognition experiences between characters, but also the acknowledgement of or resistance against unjust and oppressive power structures through recognition. To explore this phenomena, I begin by assessing the experience of empathy – or moral imagination, according to Martha Nussbaum – in reading and in writing, along …


Programming By Voice, Sadia Nowrin Jan 2024

Programming By Voice, Sadia Nowrin

Dissertations, Master's Theses and Master's Reports

Programmers typically rely on a keyboard and mouse for input, which poses significant challenges for individuals with motor impairments, limiting their ability
to effectively input programs. Voice-based programming offers a promising alternative,
enabling a more inclusive and accessible programming environment. Insights from interviews with motor-impaired programmers revealed that memorizing unnatural commands in existing voice-based programming systems led to frustration. In this work, we explore how programmers naturally speak a single line of code and present a comprehensive methodology for a voice programming system aimed at making programming more accessible for diverse users. To achieve this, we adopted a two-step pipeline. …


Divergent Response To Anthropogenic Change Within The Songbird Taxon: Insights From The Range Expansion Of The Northern Cardinal And Mitigation Mechanisms For Migratory Bird-Building Collisions, Jenna Brewer Jan 2024

Divergent Response To Anthropogenic Change Within The Songbird Taxon: Insights From The Range Expansion Of The Northern Cardinal And Mitigation Mechanisms For Migratory Bird-Building Collisions, Jenna Brewer

Dissertations, Master's Theses and Master's Reports

Anthropogenic activities have impacted ecosystems across the globe. However, wildlife species have exhibited heterogenous responses to these novel changes, with some species experiencing population growth, and others succumbing to population decline. I studied examples of both within the songbird taxon, focusing on drivers of range expansion in the Northern Cardinal and acoustic mitigation mechanisms for migratory bird-building collisions, a source of decline for many songbird species. I found that the Northern Cardinal’s range was primarily a function of climatic stress, which was supported by the modulation of the molt process across latitudes. Specifically, Northern Cardinals exhibited faster feather growth rates …


A Virtual Time Driven Simulator For Devs Models, Ronald R. Stempien Jan 2024

A Virtual Time Driven Simulator For Devs Models, Ronald R. Stempien

Dissertations, Master's Theses and Master's Reports

When simulating a system that includes some software component, simulation authors are faced with the problem of how to appropriately model the software within the simulation. While many formal methods for modeling software exist, in some contexts these may not be appropriate or viable for a given simulation. Instead, simulation authors may model a computer within the simulation, and run the software in question “as is” on the modeled machine. In this work, we introduce a theoretical framework to allow for the use of hardware virtualization technologies as a hardware accelerator for CPU models in Discrete Event System Specification (DEVS) …


Dynamic Memory Management For Key-Value Store, Yuchen Wang Jan 2024

Dynamic Memory Management For Key-Value Store, Yuchen Wang

Dissertations, Master's Theses and Master's Reports

To minimize the latency of accessing back-end servers, modern web services often use in-memory key-value (k-v) stores at the front end to cache frequently accessed objects. Due to the limited memory capacity, these stores must be configured with a fixed amount of memory. Consequently, cache replacement is required when the footprint of the accessed objects exceeds the cache size.

This thesis presents a comprehensive exploration of advanced dynamic memory management techniques for k-v stores. The first study conducts a detailed analysis of K-LRU, a random sampling-based replacement policy, proposing a dynamic K configuration scheme to exploit the potential miss ratio …


Halide-Assisted Growth Of Transition Metal Dichalcogenides, Vinaayak Sivam Balasubramaniam Jan 2024

Halide-Assisted Growth Of Transition Metal Dichalcogenides, Vinaayak Sivam Balasubramaniam

Dissertations, Master's Theses and Master's Reports

Monolayers of transition metal dichalcogenides (TMDCs) have attracted significant attention as the rare two-dimensional (2D) semiconducting materials with a direct energy band gap. Chemical vapour deposition (CVD) is one of the scalable techniques to grow atomically thin TMDC monolayers in high quality, but it requires high growth temperature. Herein we report the growth of MoS2, WS2 and MoSe2 by a one-step halide-assisted CVD method using NaCl and KCl as the catalysts. These halides could reduce the growth temperature of TMDCS by reacting with the precursors (TMDC powders) to form volatile intermediate compounds as the growth species. We use optical microscopy, …


Continuous, Platform Purification Of Viral Products Using Aqueous Two-Phase Extraction, Natalie M. Nold Jan 2024

Continuous, Platform Purification Of Viral Products Using Aqueous Two-Phase Extraction, Natalie M. Nold

Dissertations, Master's Theses and Master's Reports

Cell and gene therapies, a ground-breaking class of drugs that can heal genetic diseases and cure cancer, often have treatment costs over $1 million. Most cell and gene therapies are delivered using virus-based delivery vectors, which are incredibly expensive to manufacture. Liquid chromatography is the favored method of viral vector purification since it is easily scalable and can be functionalized to purify by biospecificity, charge, hydrophobicity, or size. However, chromatography-based purification processes are highly expensive and usually only recover 20-50% of the viral vectors. There is currently no platform purification strategy for viral vectors due to differences in their surface …


Colombia´S National Mountain Peatland Map: Peatland Distribution, Condition And Carbon Stocks, Patrick Nicolas Skillings-Neira Jan 2024

Colombia´S National Mountain Peatland Map: Peatland Distribution, Condition And Carbon Stocks, Patrick Nicolas Skillings-Neira

Dissertations, Master's Theses and Master's Reports

In this research, I explore the distribution, condition, and carbon stocks of peatlands in the Colombian Andes. High mountain peatlands in Colombia, usually found within the páramos, face significant ecological challenges. Although Law 1930 (2018) mandates sustainable páramo management, it does not prohibit peatland disturbance. Undisturbed peatlands act as long-term carbon sinks, but their degradation can convert them into greenhouse gas sources. The lack of comprehensive national peatland mapping hampers effective environmental management and policy formulation. I aim to create a national-scale peatland map, assess peatland distribution, quantify degraded pasture peatlands, and report preliminary soil carbon stocks. Additionally, I compared …


Model Guided Memory Optimization For Key-Value Caches, Daniel Byrne Jan 2024

Model Guided Memory Optimization For Key-Value Caches, Daniel Byrne

Dissertations, Master's Theses and Master's Reports

Modern web services deploy key-value caches to store popular requests to backend systems. As such, how the cache stores data impacts both the cache miss ratio and throughput. Therefore, in this thesis, we introduce and apply cache modeling techniques to optimize the memory organization of a key-value cache to improve overall cache performance.

Specifically, we begin with a single-level key-value cache and use miss ratio curves to adjust the memory assigned to the residing applications dynamically. This leads to an improvement in miss ratio up to 25% over state-of-the-art techniques and an 8.8% improvement in cache throughput. We then consider …


Optimizing Diabetes Diagnostics: Electrophoretic Separation And Detection Of Hemoglobin A1c With Boronate, Rixlie Fozilova Jan 2024

Optimizing Diabetes Diagnostics: Electrophoretic Separation And Detection Of Hemoglobin A1c With Boronate, Rixlie Fozilova

Dissertations, Master's Theses and Master's Reports

Diabetes affects 537 million people worldwide, while 136 million Americans have diabetes or prediabetes; roughly 22.6% of individuals are undiagnosed. Diabetes is the inability to regulate blood sugar levels. Hemoglobin A1c (HbA1c) is glycosylated hemoglobin and indicates average blood sugar levels over the past three months.

We adapted the selective boronic acid binding to the HbA1c sugar moieties from boronate affinity chromatography and translated it into a portable microchip paper-based electrophoresis platform. We explored a range of boronate concentrations at a steady voltage and sample volume to determine the optimal HbA1c binding and subsequent electrophoretic separation. A pH above 11 …