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Full-Text Articles in Physical Sciences and Mathematics

Modeling The Heterogeneous Temporal Dynamics Of Epidemics On Networks, Andrea Joan Allen Jan 2022

Modeling The Heterogeneous Temporal Dynamics Of Epidemics On Networks, Andrea Joan Allen

Graduate College Dissertations and Theses

Mathematical models of infectious disease are important tools for understanding large-scale patterns of how a disease spreads through a population. Predictions of trends from disease models help guide public health prevention and mitigation measures. Most simple disease models assume that the population is randomly mixed, but real-world populations exhibit heterogeneous patterns in the way people interact. These differences in population structure can be represented by networks. Networks can then be incorporated into disease models by using various interdisciplinary concepts and tools. Yet even network disease models often overlook that populations change over time. In this thesis, two models of infectious …


Design Of Green Stormwater Infrastructure In Cold Climates: Material Selection, Phosphorus Dynamics, And Road Salt Effects, Marcos Lucianus Kubow Jan 2022

Design Of Green Stormwater Infrastructure In Cold Climates: Material Selection, Phosphorus Dynamics, And Road Salt Effects, Marcos Lucianus Kubow

Graduate College Dissertations and Theses

Urbanization has led to increased impervious surface area in watersheds globally, contributing to increased stormwater discharge and nutrient loading to aquatic ecosystems. Freshwater ecosystems like Lake Champlain have been negatively impacted by harmful algal blooms driven by excess phosphorus (P) loading. Additionally, salinization from chloride (Cl-) in road salts used in developed areas is a growing concern for freshwater ecosystems in cold climates. Green stormwater infrastructure (GSI) is a best management practice (BMP) intended to mitigate increased runoff and nutrient loading. Many states require the incorporation of GSI in new development plans, but better guidance is needed for the materials …


Enhancing Zero-Shot And Few-Shot Text Classification Using Pre-Trained Language Models, Yanan Chen Jan 2022

Enhancing Zero-Shot And Few-Shot Text Classification Using Pre-Trained Language Models, Yanan Chen

Theses and Dissertations (Comprehensive)

In recent years, the community of natural language processing (NLP) has seen amazing progress in the development of pre-trained language models (PLMs). The novel paradigm of PLMs does not require labeled data, allowing us to experiment with increased training scale through employing freely available colossal online self-training corpus to push the limits. Language models (LMs), such as GPT, BERT and T5, have achieved high performance on a wide range of NLP tasks. Meanwhile, research on zero-shot and few-shot text classification has received increasing attention. As labelling can be costly and time-consuming, how to perform data augmentation (DA) and enhance the …


Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina Jan 2022

Unearthing The Effects Of European-American Settlement On A Northeast Ohio Kettle Lake Through Diatom Stratigraphy, Justine Paul A. Berina

Senior Independent Study Theses

Recently, wetland conservation has highlighted the necessity for assessing limnological changes following European-American settlement. A prior study at Brown's Lake (northeast Ohio) identified a stratigraphic sequence that shows an abrupt transition from organic-rich muds to several centimeters of a bright loess layer, then a recovery to organic-rich sediments near the top. Based on 210Pb dates, the loess deposition occurred before 1846 CE, when a growing population cleared trees and farmed intensively. Likewise, organics had recovered after 1950 CE, when people abandoned farmland and practiced conservation tillage. However, the effects of settlement on limnology are poorly known. Diatoms (microscopic algae; …


Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman Jan 2022

Model Of A Biotic Hard Substrate Community: Paleoecology Of Large Trepostome Bryozoans From The Upper Ordovician (Katian) Of The Cincinnati Region, Usa, Kate Runciman

Senior Independent Study Theses

The calcite skeletons of trepostome bryozoan colonies from the Upper Ordovician (Katian) of the Cincinnati region record the diverse interactions and growth responses these colonies experienced. Trepostome specimens from three Cincinnatian strata; the Bellevue Member, the Bull Fork Formation, and the Whitewater Formation, were studied within this project. These three strata were deposited in a shallow epicontinental sea environment that was located in the southern subtropics, approximately 20-23°S at the time of deposition. The focus of this project was the paleoecology of large trepostome bryozoans, which was studied by examining bryozoan growth patterns, trace fossils, and sedimentation. Microscopic examination of …


Framework For Sustainable Pastoral Management - Land Condition Version, R Fletcher Jan 2022

Framework For Sustainable Pastoral Management - Land Condition Version, R Fletcher

Natural resources published reports

This document outlines the revised edition of the Framework for sustainable pastoral management, with a particular emphasis on the land condition components, including the monitoring, assessment and compliance processes. These processes are now being used to guide the management of land condition on all pastoral leases and stations within Western Australia (WA), which cover 860,000 km2 and represents over 40% of WA’s extensive rangeland area.


Sediment Survey: Yr060823, Station 3917, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs Jan 2022

Sediment Survey: Yr060823, Station 3917, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs

Data

This dataset consists of sediment properties including grain size distribution, percent moisture, percent organic matter, sediment bed erodibility, as well as (in most cases) x-ray images of the sediment structure. Most samples were taken in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Sediment Survey: Yr070322, Station 3929, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs Jan 2022

Sediment Survey: Yr070322, Station 3929, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs

Data

This dataset consists of sediment properties including grain size distribution, percent moisture, percent organic matter, sediment bed erodibility, as well as (in most cases) x-ray images of the sediment structure. Most samples were taken in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Sediment Survey: Yr070323, Station 3930, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs Jan 2022

Sediment Survey: Yr070323, Station 3930, Clay Bank, York River Virginia, Grace M. Massey, Patrick J. Dickhudt, Carl T. Friedrichs

Data

This dataset consists of sediment properties including grain size distribution, percent moisture, percent organic matter, sediment bed erodibility, as well as (in most cases) x-ray images of the sediment structure. Most samples were taken in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Sediment Survey: Yr111212, Station S4985-S4988, Clay Bank, York River Virginia, Grace M. Massey, Kelsey A. Fall, Carl T. Friedrichs Jan 2022

Sediment Survey: Yr111212, Station S4985-S4988, Clay Bank, York River Virginia, Grace M. Massey, Kelsey A. Fall, Carl T. Friedrichs

Data

This dataset consists of sediment properties including grain size distribution, percent moisture, percent organic matter, sediment bed erodibility, as well as (in most cases) x-ray images of the sediment structure. Most samples were taken in support of an Acoustic Doppler Velocimeter (ADV) tripod deployed in nearby location.


Tower Deployment: Yr141125 To Yr150316, Adv, Clay Bank, York River Virginia, Grace M. Massey, Kelsey A. Fall, Carl T. Friedrichs Jan 2022

Tower Deployment: Yr141125 To Yr150316, Adv, Clay Bank, York River Virginia, Grace M. Massey, Kelsey A. Fall, Carl T. Friedrichs

Data

Dataset consists of data collected during a tower deployment of four Nortek Vector ADV sensors which were mounted at different depths in the water column to monitor suspended sediment concentrations and sizes. Conductivity and temperature were also monitored at corresponding depths.


The Atlantic Surfclam Fishery And Offshore Wind Energy Development: 1. Model Development And Verification, Daphne M. Munroe, Eric N. Powell, John M. Klinck, Andrew M. Scheld, Sarah Borsetti, Jennifer Beckensteiner, Eileen E. Hofmann Jan 2022

The Atlantic Surfclam Fishery And Offshore Wind Energy Development: 1. Model Development And Verification, Daphne M. Munroe, Eric N. Powell, John M. Klinck, Andrew M. Scheld, Sarah Borsetti, Jennifer Beckensteiner, Eileen E. Hofmann

CCPO Publications

Competing pressures imposed by climate-related warming and offshore development have created a need for quantitative approaches that anticipate fisheries responses to these challenges. This study used a spatially explicit, ecological-economic agent-based model integrating dynamics associated with Atlantic surfclam stock biology, decision-making behavior of fishing vessel captains, and fishing fleet behavior to simulate stock biomass, and fishing vessel catch, effort and landings. Simulations were implemented using contemporary Atlantic surfclam stock distributions and characteristics of the surfclam fishing fleet. Simulated distribution of fishable surfclam biomass was determined by a spatially varying mortality rate, fishing by the fleet was controlled by captain decisions …


(Re)Empowering The Community: A Case Study Of Namibia's Legal Evolution Of Wildlife Governance, Stefan Carpenter Jan 2022

(Re)Empowering The Community: A Case Study Of Namibia's Legal Evolution Of Wildlife Governance, Stefan Carpenter

William & Mary Environmental Law and Policy Review

This Article will introduce the theoretical foundation of the CBC [Community-Based Conservation] approach. It will then use Namibia as a case study to both: (a) illustrate the sort of historical, political, and economic drivers that motivate the adoption of CBC across the global south, and (b) highlight the existence of potential structural weaknesses present in even the most lauded CBC programs. Finally, this Article will present some of the common theoretical and results-based criticisms of CBC and discuss broader lessons that can be drawn from the Namibian experience. The analyses in this Article draw from academic literature, Namibia’s statutes and …


The Water Is On Fire: Current Circuit Approaches To Fee-Shifting In Citizen-Suits Under The Clean Water Act And The Need For Clearer And More Uniform Standards, Charles Kinley Jan 2022

The Water Is On Fire: Current Circuit Approaches To Fee-Shifting In Citizen-Suits Under The Clean Water Act And The Need For Clearer And More Uniform Standards, Charles Kinley

William & Mary Environmental Law and Policy Review

This Note will start by providing a short explanation of the origins of and congressional goals for the fee-shifting provision in the CWA [Clean Water Act]. It will then offer a brief summary of how Supreme Court precedent has both clarified and confused this issue. Then, it will dive into an examination of how the different circuits and their district courts have interpreted the CWA’s fee-shifting provision and how these interpretations have struggled with past Supreme Court decisions. Finally, this Note will explore the costs and benefits associated with these fee-shifting standards and offer a potential solution to this problem. …


Bounded-Degree Plane Geometric Spanners: Connecting The Dots Between Theory And Practice, Matthew Alexander Graham Jan 2022

Bounded-Degree Plane Geometric Spanners: Connecting The Dots Between Theory And Practice, Matthew Alexander Graham

UNF Graduate Theses and Dissertations

The construction of bounded-degree plane geometric spanners has been a focus of interest since 2002 when Bose, Gudmundsson, and Smid proposed the first algorithm to construct such spanners. To date, eleven algorithms have been designed with various trade-offs in degree and stretch factor. We have implemented these sophisticated algorithms in C++ using the CGAL library and experimented with them using large synthetic and real-world pointsets. Our experiments have revealed their practical behavior and real-world efficacy. We share the implementations via GitHub for broader uses and future research.

We present a simple practical algorithm, named AppxStretchFactor, that can estimate stretch factors …


An Audio Processing Pipeline For Acquiring Diagnostic Quality Heart Sounds Via Mobile Phone, Davoud Shariat Panah, Andrew Hines, Joseph Mckeever, Susan Mckeever Jan 2022

An Audio Processing Pipeline For Acquiring Diagnostic Quality Heart Sounds Via Mobile Phone, Davoud Shariat Panah, Andrew Hines, Joseph Mckeever, Susan Mckeever

Articles

Recently, heart sound signals captured using mobile phones have been employed to develop data-driven heart disease detection systems. Such signals are generally captured in person by trained clinicians who can determine if the recorded heart sounds are of diagnosable quality. However, mobile phones have the potential to support heart health diagnostics, even where access to trained medical professionals is limited. To adopt mobile phones as self-diagnostic tools for the masses, we would need to have a mechanism to automatically establish that heart sounds recorded by non-expert users in uncontrolled conditions have the required quality for diagnostic purposes. This paper proposes …


Drivers Of Environmental Degradation In Turkey: Designing An Sdg Framework Through Advanced Quantile Approaches, Tomiwa Sunday Adebayo, Ephraim Bonah Agyekum, Salah Kamel, Hossam Zawbaa, Mehmet Altuntaş Jan 2022

Drivers Of Environmental Degradation In Turkey: Designing An Sdg Framework Through Advanced Quantile Approaches, Tomiwa Sunday Adebayo, Ephraim Bonah Agyekum, Salah Kamel, Hossam Zawbaa, Mehmet Altuntaş

Articles

Turkey is a laggard in terms of the achievement of its Sustainable Development Goals (SDGs), and one of the primary issues it faces is environmental deterioration. Therefore, a policy-level reorientation may be needed to address this relevant issue. From this standpoint, this research assesses the impact of renewable energy (RE) use and financial development on the emissions of CO2 as well as the role of urbanization and agriculture, utilizing a dataset stretching between 1985 and 2019. By applying the innovative quantile-on-quantile regression (QQR) and non-parametric Granger causality in quantiles techniques, the study assesses the ways in which the quantiles of …


Interconnection And Damping Assignment Passivity-Based Non-Linear Observer Control For Efficiency Maximization Of Permanent Magnet Synchronous Motor, Youcef Belkhier, Abelyazid Achour, Miroslav Bures, Nasim Ullah, Mohit Bajaj, Hossam Zawbaa, Salah Kamel Jan 2022

Interconnection And Damping Assignment Passivity-Based Non-Linear Observer Control For Efficiency Maximization Of Permanent Magnet Synchronous Motor, Youcef Belkhier, Abelyazid Achour, Miroslav Bures, Nasim Ullah, Mohit Bajaj, Hossam Zawbaa, Salah Kamel

Articles

The permanent magnet synchronous motor (PMSM) has several advantages over the DC motor and is gradually replacing it in the industry. The dynamics of the PMSM are described by non-linear equations; it is sensitive to unknown external disturbances (load), and its characteristics vary over time. All of these restrictions complicate the control task. Non-linear controls are required to adjust for non-linearities and the drawbacks mentioned above. This paper investigates an interconnection and damping assignment (IDA) passivity-based control (PBC) combined with a non-linear observer approach for the PMSM using the model represented in the dq-frame. The IDA-PBC approach has the inherent …


Residential Demand Side Management Model, Optimization And Future Perspective: A Review, Subhasis Panda, Sarthak Mohanty, Pravat Kumar Rout, Binod Kumar Sahu, Mohit Bajaj, Dr Hossam Zawbaa, Salah Kamel Jan 2022

Residential Demand Side Management Model, Optimization And Future Perspective: A Review, Subhasis Panda, Sarthak Mohanty, Pravat Kumar Rout, Binod Kumar Sahu, Mohit Bajaj, Dr Hossam Zawbaa, Salah Kamel

Articles

The residential load sector plays a vital role in terms of its impact on overall power balance, stability, and efficient power management. However, the load dynamics of the energy demand of residential users are always nonlinear, uncontrollable, and inelastic concerning power grid regulation and management. The integration of distributed generations (DGs) and advancement of information and communication technology (ICT) even though handles the related issues and challenges up to some extent, till the flexibility, energy management and scheduling with better planning are necessary for the residential sector to achieve better grid stability and efficiency. To address these issues, it is …


An Improved Wild Horse Optimization Algorithm For Reliability Based Optimal Dg Planning Of Radial Distribution Networks, Mohammed Hamouda Ali, Salah Kamel, Mohamed H. Hassan, Marcos Tostado-Véliz, Hossam Zawbaa Jan 2022

An Improved Wild Horse Optimization Algorithm For Reliability Based Optimal Dg Planning Of Radial Distribution Networks, Mohammed Hamouda Ali, Salah Kamel, Mohamed H. Hassan, Marcos Tostado-Véliz, Hossam Zawbaa

Articles

This paper introduces a novel technique for optimal distribution system (DS) planning with distributed generation (DG) systems. It is being done to see how active and reactive power injections affect the system’s voltage profile and energy losses. DG penetration in the power systems is one approach that has several advantages such as peak savings, loss lessening, voltage profile amelioration. It also intends to increase system reliability, stability, and security. The main goal of optimal distributed generation (ODG) is a guarantee to achieve the benefits mentioned previously to increase the overall system efficiency. For extremely vast and complicated systems, analytical approaches …


Modeling And Sensitivity Analysis Of Grid-Connected Hybrid Green Microgrid System, Sumit Sharma, Yog Raj Sood, Naveen Kumar Sharma, Mohit Bajaj, Hossam Zawbaa, Rania A. Turky, Salah Kamel Jan 2022

Modeling And Sensitivity Analysis Of Grid-Connected Hybrid Green Microgrid System, Sumit Sharma, Yog Raj Sood, Naveen Kumar Sharma, Mohit Bajaj, Hossam Zawbaa, Rania A. Turky, Salah Kamel

Articles

The demonstrated research work analyses the technoeconomic modelling and sensitivity analysis of the available resources for the rural community in India. The various resources used in this study are solar, wind, hydro, battery and utility grid-connected system. The usefulness of the on-grid system in the rural sector is that excess amount of electricity produced through renewable energy sources (RES) could be sold back to the utility grid. A total of 12 possible configurations of various resources with and without a grid-connected system was analyzed for minimum Levelized Cost of Energy (LCOE) and Total Net Present Cost (TNPC). Further, sensitivity analysis …


Effect Of Cryogenic Treatment On Drill Tool For Enhancing Metal Cutting Operation Of Aluminium Alloy Is737.Gr19000, G. Navaneethakrishnan, B. Sureshkumar, R. Palanisamy, Mohit Bajaj, Hossam Zawbaa, Salah Kamel Jan 2022

Effect Of Cryogenic Treatment On Drill Tool For Enhancing Metal Cutting Operation Of Aluminium Alloy Is737.Gr19000, G. Navaneethakrishnan, B. Sureshkumar, R. Palanisamy, Mohit Bajaj, Hossam Zawbaa, Salah Kamel

Articles

Drilling is the hole making process on the component face with the aid of a twisted drillbit. Normal drill bits easily wear out through penetration of drill bit into the workpiece material due to force generated in the drilling operation. So this work tries to investigate the machining parameters with cryogenically treated drill bits on various responses. Cryogenic treatment is one of the thermal engineering processes, which is used to cool the material from the temperature of −150 °C to −273 °C. This research work utilizes cryogenically treated drill tools for investigating the drilling performance on aluminium alloy (IS737.Gr19000) workpiece …


Image-Based Malware Classification Hybrid Framework Based On Space-Filling Curves, Stephen O Shaughnessy, Stephen Sheridan Jan 2022

Image-Based Malware Classification Hybrid Framework Based On Space-Filling Curves, Stephen O Shaughnessy, Stephen Sheridan

Articles

There exists a never-ending “arms race” between malware analysts and adversarial malicious code developers as malevolent programs evolve and countermeasures are developed to detect and eradicate them. Malware has become more complex in its intent and capabilities over time, which has prompted the need for constant improvement in detection and defence methods. Of particular concern are the anti-analysis obfuscation techniques, such as packing and encryption, that are employed by malware developers to evade detection and thwart the analysis process. In such cases, malware is generally impervious to basic analysis methods and so analysts must use more invasive techniques to extract …


Towards An Inclusive Co-Design Toolkit: Perceptions And Experiences Of Co-Design Stakeholders, Eamon Aswad, Emma Murphy, Claudia Fernandez-Rivera, Sarah Boland Jan 2022

Towards An Inclusive Co-Design Toolkit: Perceptions And Experiences Of Co-Design Stakeholders, Eamon Aswad, Emma Murphy, Claudia Fernandez-Rivera, Sarah Boland

Articles

Participatory design holds great potential for the creation of inclusive technology but existing toolkits and resources to support co-design are not always accessible to designers and co-designers with disabilities. In this paper we present two studies to assist in facilitating the creation of a sustainable, accessible, inclusive co-design toolkit for individuals with intellectual disabilities i) exploration of the perceptions and experiences of lecturers (n =5) and students (n= 5) involved in co-design activities via individual interviews and ii) a protocol and initial findings from focus groups with men and women with intellectual disabilities to inform on best co-design practices (n=15). …


An Image Processing Based Classifier To Support Safe Dropping For Delivery-By-Drone, Assem A. Abdelhak, Alan Hicks, Dan Moss, Susan Mckeever Jan 2022

An Image Processing Based Classifier To Support Safe Dropping For Delivery-By-Drone, Assem A. Abdelhak, Alan Hicks, Dan Moss, Susan Mckeever

Articles

Autonomous delivery-by-drone of packages is an active area of research and commercial development. However, the assessment of safe dropping/ delivery zones has received limited attention. Ensuring that the dropping zone is a safe area for dropping, and continues to stay safe during the dropping process is key to safe delivery. This paper proposes a simple and fast classifier to assess the safety of a designated dropping zone before and during the dropping operation, using a single onboard camera. This classifier is, as far as we can tell, the first to address the problem of safety assessment at the point of …


The Value Of Peer Mentoring Networks For Developing Leaders And Inspiring Change, Chrystal D. Bruce, Patricia M. Flatt, Sarah R. Kirk, Elizabeth Roberts-Kirchhoff, Hala G. Schepmann Jan 2022

The Value Of Peer Mentoring Networks For Developing Leaders And Inspiring Change, Chrystal D. Bruce, Patricia M. Flatt, Sarah R. Kirk, Elizabeth Roberts-Kirchhoff, Hala G. Schepmann

2022 Faculty Bibliography

A peer-mentoring network, funded by the National Science Foundation ADVANCE program, profoundly impacted the career trajectory of five women chemistry faculty at predominantly undergraduate institutions. By providing each other support, encouragement, information, and accountability, we advanced our careers, became leaders in our own right, and implemented change at our institutions. To extend this benefit to more women STEM faculty, we have developed and implemented a model to support 74 faculty and administrators representing 51 institutions across the country.


How Adolescents In The Child Welfare System Seek Support For Their Sexual Risk Experiences Online, Taylor L. Moraguez Jan 2022

How Adolescents In The Child Welfare System Seek Support For Their Sexual Risk Experiences Online, Taylor L. Moraguez

Honors Undergraduate Theses

Youth in the foster care system experience unique and challenging situations online, such as higher risks of inappropriate messaging (e.g., sexting) and unwanted solicitations from strangers. As a vulnerable group of adolescents, foster youth often use online platforms as a resource to express themselves and seek support over their sexual experiences online. This thesis analyzes how foster youth seek support online for their sexual risk experiences, including sexual abuse, sexting, and sexuality. To understand how adolescents (ages 13-17) in the child welfare system seek support for these experiences, we conducted a thematic analysis of 541 individual posts made by 121 …


Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar Jan 2022

Investigation Of Dna Hybridization In Localized Systems In Close Proximity, Ashley M. Sewsankar

Honors Undergraduate Theses

Hybridization of two or more DNA or RNA strands is well documented for the process taking place with all strands free in solution or when one strand is immobilized on a substrate. This study contributes to the investigation of the hybridization process when two single DNA strands (ssDNA) are in close proximity. We took advantage of an X sensor in which hybridization of four DNA strands enables the formation of a DNA four-way junction (crossover or X) structure. We immobilized multiple layers of crossover structures to study its hybridization being triggered by short ssDNA coming from solution and further investigate …


Containing Compounding Container Congestion, Curtis Salinger Jan 2022

Containing Compounding Container Congestion, Curtis Salinger

CMC Senior Theses

The Covid-19 pandemic caused major disruptions throughout the container shipping supply chain. Professor Dongping Song of Liverpool University wrote a paper discussing the logistical vulnerabilities in the supply chain, including the issue of congestion in ports. This paper examines the Port of Los Angeles from 2018-2021 as it relates to Song’s paper to see how its operations were impacted during the Covid-19 timeframe. It is found that labor shortages, chassis shortages, and change in trade behavior each contributed to the congestion. Unfortunately, the implemented policies were insufficient to bolster the port against sustained challenges and congestion continues to worsen.


Topological Hierarchies And Decomposition: From Clustering To Persistence, Kyle A. Brown Jan 2022

Topological Hierarchies And Decomposition: From Clustering To Persistence, Kyle A. Brown

Browse all Theses and Dissertations

Hierarchical clustering is a class of algorithms commonly used in exploratory data analysis (EDA) and supervised learning. However, they suffer from some drawbacks, including the difficulty of interpreting the resulting dendrogram, arbitrariness in the choice of cut to obtain a flat clustering, and the lack of an obvious way of comparing individual clusters. In this dissertation, we develop the notion of a topological hierarchy on recursively-defined subsets of a metric space. We look to the field of topological data analysis (TDA) for the mathematical background to associate topological structures such as simplicial complexes and maps of covers to clusters in …