Digital Commons Network^™

Ac Direct Drive Led Lighting Using Low Cost Analog Components, Miles Head

Master's Theses

This project explores the rapidly expanding area of AC direct drive for LED lighting. AC LED driving does not use typical DC-DC converter-based driving but uses semiconductor switches and a linear regulator to activate a number of LEDs proportional to the input voltage at any given time. This allows bulky, expensive magnetics to be eliminated from the system. The goal of this project was to design a scaled-down physical AC LED direct drive system to validate the conclusions of methods for improving efficiency from a previous investigation that found minimizing voltage across the linear regulating MOSFET led to higher efficiency …

Macrobenthos Responses To Dam Removal And Habitat Restoration In The West River, Connecticut, Robert W. Sheridan

Master's Theses

Dam removal is being increasingly used nationwide to restore impaired rivers and streams. While dam removals are becoming more prevalent, little is known about whether these efforts create conditions for the enhancement and or establishment of desired biota.

Ongoing monitoring of these projects is an important step in the restoration process to ensure project goals are being met and the restoration has been successful.

This thesis focuses on the Pond Lily Dam removal and restoration which took place in October 2015 along the West River in New Haven Connecticut that removed an aging mill dam with the objective of restoring …

Benchmarking Oecd Countries’ Sustainable Development Performance: A Goal-Specific Pca Approach, Shyam Lamichhane

Master's Theses

In this thesis, the current status of the Organisation for Economic Co-operation and Development (OECD) countries’ sustainable development performance towards reaching the recently announced 2030 Agenda (17 UN Sustainable Development Goals (SDGs)) was investigated. Over 90 social, economic and environmental sustainability indicators were considered for the performance assessment of OECD countries towards reaching the targeted SDGs. The current weighted averaging approach used in the recent SDG Index and Dashboards Report was used as the benchmark and its limitations were discussed. To overcome the limitations, a novel Goal Specific Principal Component Analysis (GS-PCA) approach was proposed to create composite sustainability index …

The Impact Of Shod Versus Unshod Walking On Center Of Pressure Variability, Zachary Barrons

Master's Theses

The purpose of the present investigation was to examine the influence of footwear on walking stability. Twenty healthy women walked at 1.3 m/s on an instrumented treadmill. One hundred steps (50-right, 50-left) were analyzed from two walking conditions (shod, unshod). The variability of the center of pressure (COP) for each step was calculated for quadrants of the contact period. Significant differences in variability were seen between shod and unshod conditions in all quadrants as well as differences between left and right feet in quadrants one and four. Restricted foot motion while shod may explain the differences seen in COP variability. …

Comparative Thermal Ecology Of Coastal And Inland Pacific Rattlesnakes (Crotalus Oreganus), Hayley Layne Crowell

Master's Theses

Global biodiversity is declining as a direct result of anthropogenic climate change. Ectothermic species have become focal organisms for studying the ecological effects of altered climates due to the clear relationship between environmental temperatures and ectotherms’ basic physiological functions. Historically, examinations of these effects have focused heavily on heliothermic lizards, and most others have tended to focus on single populations or sympatric species within a single community. Addressing the longterm energetic implications of environmental temperature variation will provide valuable insight into the cascading physiological effects that certain populations or species may experience as a result of altered climates.

In this …

Exploring The Influence Of School-Based Sexuality Education Settings On Lgbtq+ Sexual Identity Development, Lauren Marie Guyer

Master's Theses

Previous research on sexual identity development demonstrates that there are five discernible, non-linear statuses in which individuals may pass through as they develop their sexual identity: compulsory heterosexuality, active exploration, diffusion, deepening and commitment, and synthesis (Dillon, Worthington, and Moradi 2011). Moreover, prior research on school-based sexuality education (SBSE) demonstrates that no matter its formal designation or political perspective, SBSE is exclusionary, inadequate, and habitually reproduces social inequalities (Bay-Cheng 2003; Elia and Eliason 2010b). SBSE programs within the United States are insufficient because they unvaryingly promote a heteronormative discourse and do not address the sexual health needs or experiences of …

Evaluating Alternate Management Strategies For Spotted Seatrout (Cynoscion Nebulosus) In The North-Central Gulf Of Mexico, Nathaniel Wallace Jermain

Master's Theses

Spotted Seatrout (Cynoscion nebulosus) receive considerable fishing pressure as the most popular saltwater target species in the north-central Gulf of Mexico. The potential for alternate management strategies, including stock enhancement and reducing discard mortality, to support the sustainability of the stocks and the desires of stakeholders is unknown. The purpose of this study was to provide an objective evaluation of the efficacy of alternate management strategies for Spotted Seatrout in Louisiana, Mississippi, and Alabama. I used a management strategy evaluation (MSE) to measure the performance of 18 alternate management scenarios relative to control scenarios. Scenarios with a high …

Geographical Analysis Of Offender Vulnerability: Modeling Coastal Hazards And Social Disorganization In Southern Mississippi, Ashleigh Nicole Price

Master's Theses

Hazards research continually examines how specific groups are affected by damaging events and how their unique sociodemographic characteristics contribute to variations in resilience and recovery. Studies have shown that underprivileged communities suffer more adversely and take longer to recover from hazard events. Probationers and parolees are uniquely disadvantaged regarding demographics and economic opportunity, both of which contribute to increased vulnerability and reduced resilience. Numerous legal restrictions and widespread discrimination towards former criminals means offenders are often relegated to underserved, criminogenic neighborhoods. Given such severe social and financial limitations, offenders have little capacity to prepare for or recover from disasters.

The …

Scl: A Lattice-Based Approach To Infer Three-Dimensional Chromosome Structures From Single-Cell Hi-C Data, Hao Zhu

Master's Theses

In contrast to population-based Hi-C data, single-cell Hi-C data are zero-inflated and do not indicate the frequency of proximate DNA segments. There are a limited number of computational tools that can model the three-dimensional structures of chromosomes based on single-cell Hi-C data.

We developed SCL (Single-Cell Lattice), a computational method to reconstruct three-dimensional (3D) structures of chromosomes based on single-cell Hi-C data. We designed a loss function and a 2D Gaussian function specifically for the characteristics of single-cell Hi-C data. A chromosome is represented as beads-on-a-string and stored in a 3D cubic lattice. Metropolis-Hastings simulation and simulated annealing are used …

Posture Affects Affordance Perception Of Reachability In Virtual Reality, Hannah Masoner

Master's Theses

Tasks such as standing and reaching require differing levels of postural stability. Postural equilibrium is necessary to perceive the location of objects (Lee, Pacheco, & Newell, 2018). Visual perception of whether an object is within reach was investigated while standing upright. Participants viewed a 3D virtual reality (VR) environment with a stimulus object (red ball) placed at different egocentric distances. Participants made affordance judgements while in a standard stance condition as well as two separate active balance conditions (yoga tree pose, and toe-to-heel pose). Feedback on accuracy was not provided, and participants were not allowed to attempt to reach. Response …

Gogo: An Improved Algorithm To Measure The Semantic Similarity Between Gene Ontology Terms, Chenguang Zhao

Master's Theses

Measuring the semantic similarity between Gene Ontology (GO) terms is an essential step in functional bioinformatics research. We implemented a software named GOGO for calculating the semantic similarity between GO terms. GOGO has the advantages of both information-content-based and hybrid methods, such as Resnik’s and Wang’s methods. Moreover, GOGO is relatively fast and does not need to calculate information content (IC) from a large gene annotation corpus but still has the advantage of using IC. This is achieved by considering the number of children nodes in the GO directed acyclic graphs when calculating the semantic contribution of an ancestor node …

Investigating Diel Periodicity In Export Flux In The Gulf Of Mexico Using A Particulate Imaging System, Justin Edward Blancher

Master's Theses

To estimate the diurnal periodicity in the biological pump, a floating array with a marine snow camera system at 150 m depth was used, and particles were imaged at a 40 second interval for a 24 to 30 hour period at five sites in the Gulf of Mexico in June 2017. Each image was processed to identify and size all the particles within the frame, which was then processed to determine diameter, an estimated volume, and settling speed for each particle. Using these parameters, particle mass was estimated using algebraically rearranged calculations for settling speed. Each hour during the deployment …

Detecting Coastal Marsh Change From Aerial Imagery Using Spectral And Textural Methods: Pascagoula River Estuary, Mississippi, 1955-2014, Margaret Claire Bell Waldron

Master's Theses

As sea level rise accelerates, coastal marsh ecosystems are increasingly vulnerable. Vertical accretion rates must exceed or keep pace with rates of sea level rise to prevent transition to open water or inland migration of marsh vegetation. While some marsh systems along the northern Gulf of Mexico coast have remained stable, others, e.g., the marshes of the Louisiana Gulf Coast, have experienced high rates of conversion to open water. This study examined the historical extent of intertidal marsh at the mouth of the Pascagoula River in Jackson County, Mississippi to determine whether marsh extent changed during the period 1955-2014 and …

Online Political Participation: Evaluation Of The Changing Effects Over Time, Gabriel Davis May

Master's Theses

The internet is a political participation medium that has been subject to constant changes. Just since 2008, there has been a significant increase in the amount of people who use the internet for political purposes. Building on the work of Brian Kruger and others I evaluate whether the internet brings new participants into the political process or if the internet only "reinforces" those who already participate. I utilize data from recent American National Election Studies to employ an ordinary least-squares regression model for recent presidential election years and assess whether the internet has brought new participants into the political fray …

A Machine Learning Approach To Network Intrusion Detection System Using K Nearest Neighbor And Random Forest, Ilemona S. Atawodi

Master's Theses

The evolving area of cybersecurity presents a dynamic battlefield for cyber criminals and security experts. Intrusions have now become a major concern in the cyberspace. Different methods are employed in tackling these threats, but there has been a need now more than ever to updating the traditional methods from rudimentary approaches such as manually updated blacklists and whitelists. Another method involves manually creating rules, this is usually one of the most common methods to date.

A lot of similar research that involves incorporating machine learning and artificial intelligence into both host and network-based intrusion systems recently. Doing this originally presented …

Attenuated Responses To Inflammatory Cytokines In Mouse Embryonic Stem Cells: Biological Implications And The Molecular Basis, Bohan Chen

Master's Theses

Embryonic stem cells (ESCs) have attracted intense interest due to their great potential for regenerative medicine. However, their immune property is an overlooked but a significant issue that needs to be thoroughly investigated not only to resolve the concern for therapeutic applications but also for further understanding the early stage of organismal development. Recent studies demonstrated that ESCs are deficient in innate immune responses to viral/bacterial infections and inflammatory cytokines. Inflammatory conditions generally inhibit cell proliferation, which could be detrimental to ESCs, since cell proliferation is their dedicated task during early embryogenesis. Thus, I hypothesize that the attenuated innate immunity …

A Framework To Analyze Energy Efficiency Of Multi-Band Spectrum Sensing Algorithms, Jay Bhadresh Patel

Master's Theses

Cognitive radio (CR) is a device which can detect wireless communication channels that are not in use and adapt its parameters intelligently. Networks with CRs use the available frequency bands much more efficiently and hence have higher data rates compare to traditional radios. Spectrum sensing is the class of techniques used by CRs to understand its wireless environment. Recent research on evaluating multi-band spectrum sensing algorithms is limited to only algorithm complexity and optimization; therefore, the primary goal of the study is to devise a novel framework that analyzes a multi-band spectrum sensing algorithm in terms of energy consumption and …

A Spatial Optimization Model For Resource Allocation For Wildfire Suppression And Resident Evacuation, Siqiong Zhou

Master's Theses

Wildland-urban interface wildfires have been a significant threat in many countries. This thesis presents an integer two-stage stochastic goal programming model for comprehensive, efficient response to wildfire including firefighting resource allocation and resident evacuation. In contrast to other natural disasters, the progression of wildfires depends on not only the probabilistic fire spread scenarios but also decisions made during firefighting. The proposed model optimizes the resource preparations before the fire starts and resource allocation decisions during the fire event. This model takes into account different wildfire spread scenarios and their impact on high-risk areas. The two objectives considered are minimizing the …

The Effect Of Porosity On Mechanical Properties Of Fused Deposition Manufactured Polymers And Composites, Eric Heartly Anderson

Master's Theses

Additive manufacturing has seen sustained growth in both consumer and industrial areas. fused deposition manufacturing (FDM), a specific additive manufacturing technology, has seen increased sales in consumer markets. In order to maintain growth, FDM will be increasingly used for load-bearing applications. However, the mechanical reliability of FDM polymers and composites is not well understood. This can be dangerous to property and safety. Presented in this paper are more than 16 distinct populations comprised of at least 23 unique tensile tests, a total of 506 tensile tests. Weibull statistics were used to quantify variance in physical properties of FDMed materials. It …

Pedagogies Of Play: An Ethnographic Analysis Of Activity-Based Learning In Two Elementary Classrooms, Chelsea Lynn Halliwell

Master's Theses

In this document I discuss the relationship between education standards for curriculum and structured play in the elementary classroom. I discuss the various forms of teacher-initiated structured play, and student-initiated informal play and resistance strategies - through participant observation, digital analysis, spatial analysis, semi-structured ethnographic interviews, and unstructured conversations - to understand the full range of learning strategies in elementary classroom settings. I analyze how these strategies relate to curricular standards, or how they might deviate from or transform those standards, which are partially shaped by federal and state education policy. I also outline and develop two hypotheses in an …

On-Demand Label Production, Robert A. Zimmerman

Master's Theses

The production and approval process for the various labels used in clinical trials wastes significant time and resources through the need to outsource label production or rely on large reams of pre-cut label stock for each revision throughout the process. An in-house, on-demand label printing and cutting system is a potential remedy to this waste. Previous work by Cheadle et al. resulted in a functional electomechanical prototype of the label cutting aspect of this research, capable of rudimentary linear cuts. In this continued research, emphasis was placed on improved label cutting capabilities and creating PC control software for label design. …

Effects Of Bio-Composites In Corrugated Sandwich Panels Under Edgewise Compression Loading, Jalen Christopher Mano

Master's Theses

Present day composite sandwich panels provide incredible strength. Their largest problem, however, is early bonding failure between the core and the skin. This is due to the low bonding surface area of present cores like honeycomb. Corrugated structures could provide a remedy for this with their much larger bonding surface area. Corrugated structures have extreme mechanical properties deeming them particularly useful in aerospace and automotive applications. However, previous research has shown that the stiffness of carbon fiber causes debonding and drastic failure when used as both a core and a skin. Bio-composites have properties that could strengthen the corrugated sandwich …

Comparison Of Lqr And Lqr-Mrac For Linear Tractor-Trailer Model, Kevin Richard Gasik

Master's Theses

The United States trucking industry is immense. Employing over three million drivers and traveling to every city in the country. Semi-Trucks travel millions of miles each week and encompass roads that civilians travel on. These vehicles should be safe and allow efficient travel for all. Autonomous vehicles have been discussed in controls for many decades. Now fleets of autonomous vehicles are beginning their integration into society. The ability to create an autonomous system requires domain and system specific knowledge. Approaches to implement a fully autonomous vehicle have been developed using different techniques in control systems such as Kalman Filters, Neural …

Ballet De La Nuit: Staging The Absolute Monarchy Of Louis Xiv, Sarah Curtis Lysgaard

Master's Theses

This thesis researches the ballet de cour spectacles of the seventeenth century French court, with a careful examination of the political and social importance of such spectacles in anticipation of reconstructing Louis XIV’s Ballet de la Nuit (Ballet of the Night), originally performed February 23, 1653 at the Louvre’s Salle de Petit Bourbon. This ballet de cour was a visual spectacle that combined music, dance, poetry, and allegory with elaborate staging and costumes. Such spectacles were first produced in France during the sixteenth century and involved the royal court not only as spectators but also as performers. The Ballet de …

The Effect Of Precipitation On Copy Number Of Nitrogenase Gene Nifh In Soil Bacteria In The Mojave Desert, Christy Armstrong

Master's Theses

Animals, plants, and microbes all rely on nitrogen to be readily available to build amino acids. The earth’s atmosphere is made of 78% nitrogen gas, but this molecule has a strong triple bond that prevents many species from utilizing it directly. Nitrogen fixation must occur in order for individuals to incorporate this nitrogen into their genome. The Mojave Desert is the most arid region in North America, averaging 3.5 inches of rain annually at its lowest elevation. Despite the extreme arid conditions, many species are supported in the region, all of which must rely on some form of nitrogen. This …

Green Stormwater Infrastructure Assessments In Santa Clara County, Ca: An In-Situ Analysis Of Select Bioretention Projects, Laura Bates

Master's Theses

Stormwater runoff, defined as rainwater that flows over impervious surfaces, is both an under-harnessed groundwater resource and the leading contributor to water body impairments due to the number of pollutants it can transport. One widely successful strategy to capture and treat stormwater runoff is to implement Green Stormwater Infrastructure (GSI): engineered green spaces to enhance the overall environmental quality of an urban landscape. GSI projects, particularly bioretention systems, capture and treat stormwater runoff through infiltration and plant absorption before it reaches receiving bodies of water. In order to operate efficiently, GSI systems require specific maintenance procedures. The purpose of this …

The Silicon Valley Approach To Poverty: Humanitarian Designers At Work In Financial Inclusion, Jeffrey Stephen Greger

Master's Theses

This thesis explores the application of ethnographic research and commercially-derived design approaches in support of financial inclusion, a global movement to bring affordable financial services to low-income and rural communities that have traditionally lacked access to these services. I collaborated with and interviewed designers and anthropologists working on financial inclusion projects that range from small, grassroots efforts to create payday loan alternatives in Silicon Valley and London, to more formal international development projects funded by large corporations and philanthropic organizations. Participants in this study shared a strong belief: ethnographic perspectives and design practices that incorporate marginalized voices into the decision-making …

Photovoltaic Waste Management And Implementing Extended Producer Responsibility In The Solar Industry In California, Lee-Tan Lu

Master's Theses

Electronic waste issues impact humans and the environment, primarily because most industrial designs have not considered the impact of products when they reach their end-of-life (EOL) stage. This study focuses on photovoltaic (PV) modules that are widely installed in California residential properties. While PV modules do not generate waste while operating, they will become waste at the end of their expected lifespan of 25 to 40 years. Thus, it is important to identify PV waste management strategies before the materials in the modules become a discard problem. In California, despite hazardous materials that are used in the production of PV …

Classification Of Hyperspectral Colon Cancer Images Using Convolutional Neural Networks, Sean Joseph Mobilia

Master's Theses

Hyperspectral images are 3-D images, which contain data in hundreds of spectral bands as opposed to 2-D images, which contain data in at most 3 bands (red, green, and blue). Hyperspectral imagery was initially developed for remote sensing; however, recently, researchers have started to see its potential in medical diagnosis and cancer detection. Hyperspectral images provide massive amounts of data about the objects they are studying, and this causes challenges during information processing. Machine learning tools, such as convolutional neural networks (CNNs), are known to be successful in extracting features and classifying traditional 2-D images. This thesis proposes CNN architectures …

Moderating Effect Of Trait Mindfulness On The Relationship Between Job Demands And Burnout Using The Job Demands-Resources Model, Anne O'Brien

Master's Theses

The Job Demands-Resources (JD-R) model was constructed to explain the antecedents, consequences, and relationships of burnout, and has provided evidence that personal resources moderate and weaken the relationship between job demands and burnout. Although much of the personal resource literature focuses on personality traits like optimism and self-esteem, the moderating effect of trait mindfulness on the relationship between job demands and job burnout has yet to be examined. The study hypothesized that mindfulness moderates the relationship between four job demands (role ambiguity, interpersonal conflict, work-life conflict, and cognitive demands) and three dimensions of burnout, such that those with higher levels …