Digital Commons Network^™

Graph Neural Network-Based Uav Coverage Planning For Robust And Efficient 3d Environments, Gal Tsfaty

Theses and Dissertations

This thesis addresses the challenge of generating optimized UAV waypoints for complete coverage of complex 3D environments, utilizing graph-based computational techniques. The proposed framework replaces computationally intensive steps—triangulation and three-coloring—within the Vantage Waypoint Set Generation Algorithm (VWSGA) pipeline with Graph Neural Networks (GNNs). By learning structural patterns, the GNN achieves scalable and robust triangulation and node classification, enabling enhanced coverage planning in irregular geometries. A novel penalty mechanism ensures alignment with graph structure during adjacency prediction. Experimental results demonstrate the effectiveness of GNNs in balancing accuracy, computational efficiency, and adaptability, advancing UAV coverage optimization.

Immersive Virtual Reality Heavy Equipment Simulator Training Effectiveness And Participant Performance Comparison, Zachary E. Calderon

Theses and Dissertations

Immersive Virtual Reality (IVR) simulator training is an interactive form of computer-based training that can positively promote the transfer of skills from training to trainees. Even at a lower physical fidelity IVR simulators may more effectively train individuals on the operation of virtual heavy equipment compared to written, demonstrative, and oral computer-based training. IVR simulator training may also be beneficial for implementation of heavy equipment operation training as a means to promote familiarization of controls and foster self-efficacy and confidence in trainees. A multi-stage IVR simulator was created for this study that both trained participants on wheel loader operations and …

Visual Segmentation For Autonomous Aircraft Landing On Austere Runways, Alissa M. Owens

Theses and Dissertations

Autonomous aircraft must land without human intervention, but existing methods rely on GPS or marked runways, which may be unavailable in austere environments. This paper presents a vision-based approach using semantic segmentation to detect runways and estimate aircraft pose by comparing camera and satellite imagery. We detail the model’s training and demonstrate its effectiveness with simulated and real UAV data.

Class Imbalance: A Landscape Of Classification Models, Joshua L. Edmonds

Theses and Dissertations

Class imbalance poses significant challenges in machine learning classification. This study evaluates the performance of seven models (ANN, k-Means, kNN, LDA, LR, SVM, XGBoost) across multiple imbalance levels (10\%, 5\%, 1 \%, 0.5\%) and investigates the effectiveness of sampling techniques (Undersampling, SMOTE, SMOTE-ENN). ANOVA results confirm that model choice is the most critical factor, with XGBoost and SVM demonstrating superior robustness. SMOTE improves recall but reduces precision, while undersampling generally degrades overall performance. While significant, imbalance levels do not play a critical role in model effectiveness.

Improving Zero Shot Learning By Linking Multi-Label Cnns With Llms, Michael A. Wegner

Theses and Dissertations

Classifying previously unseen objects poses a significant challenge for traditional computer vision algorithms, which rely on extensive labeled training data. Zero-shot reasoning offers a way to overcome this limitation. This research explores a novel method for image recognition using the Animals with Attributes 2 (AWA2) dataset as a proof of concept. A multi-label ResNet50 model predicts core attributes like color, ear shape, or number of limbs. Those attributes then feed into ChatGPT which leverages its extensive knowledge base to classify the animal based on the provided attributes. This novel approach skips the need to train on every possible class. Instead, …

An Analysis Of Development Phase Nre/Rec Costs In Dod Acquisition Efforts, Jason Aristizabal

Theses and Dissertations

Estimating Nonrecurring Engineering (NRE) and Recurring Engineering (REC) costs in defense acquisition programs remains challenging, especially in development. While production costs are studied, NRE/REC ratios in development receive little attention. This study analyzes NRE/REC ratios across WBS elements, commodity types, and time periods using defense program data. Results show significant variability, challenging the assumed 1:1 ratio. System Level, PME, and ST&E elements follow distinct trends, highlighting shifting cost structures. These findings stress the need for adaptive methodologies, enabling cost analysts to refine estimates based on historical trends and program-specific factors for improved resource planning.

Commercial Satellite Payload Trends, Alexander B. Krawietz

Theses and Dissertations

This thesis examines the evolving trends in commercial satellite payloads with an emphasis on mass, operating power, and project duration overall and across different payload types, serving as a benchmark for Department of Defense (DoD) leaders to compare against private industry advancements. Utilizing a comprehensive dataset of open-source commercial satellite data, this study identifies significant trends that could influence cost estimation, schedule estimation, and satellite design. The analysis not only highlights the technological progression over several decades but also provides a comparative insight into how the United States and China are positioned in their race for space dominance. Beyond detecting …

Hypergame Models For Cyber Defense In A Purple Team Setting, Thomas N. Whitney

Theses and Dissertations

Hypergame theory and purple teaming are two fields that can support an increased cybersecurity posture. This research investigates a hypergame theory framework that incorporates fittingly into the purple team feedback loop. Additionally, this research integrates empirical data into the hypergames. The data and the hypergames are supported by the MITRE ATT&CK framework. This research also includes a review of available game theory and hypergame theory software, five different hypergame models, a comparison of the two hypergame formats, and an innovative analysis technique using a multi-stage hypergame to represent the cyber kill chain. One finding of this research is that a …

Reinforcement Learning For Aeromedical Evacuation In Nonstationary Combat Environments, Micah J. Kartchner

Theses and Dissertations

This research formulates the medical evacuation (MEDEVAC) dispatching problem as a sequential decision process and investigates the application of reinforcement learning under nonstationary conditions. We model the dynamic arrival rate of MEDEVAC requests using a nonstationary Hawkes process and design a Double Deep Q-Network algorithm that incorporates belief states to anticipate future requests. Through computational experimentation, we analyze the impact of belief formulation on decision quality and system performance. Results indicate that policies incorporating belief states significantly outperform myopic dispatching policies, reducing urgent casualty wait times by up to 49.68% and increasing on-time evacuations by up to 21.91%.

Evaluating Atmospheric Water Generation For The Indo-Pacific: Predictive Modeling, Energy Considerations, And Regional Viability, Jose I. De La Serna

Theses and Dissertations

Atmospheric Water Generator (AWG) technology presents a promising solution for extracting and harvesting water from ambient air through condensation methods. This innovative approach offers a viable alternative for water production in regions with limited or unreliable water sources. AWGs operate most effectively in hot and humid environments, typically at temperatures of 80°F and relative humidity levels of 80%. As of 2020, the Department of Defense (DoD) has identified the Indo-Pacific region as a strategic focus for addressing future greatpower competition. Within the framework of Agile Combat Employment, this study evaluates the feasibility and performance of AWG technology at pre-determined locations …

Material Classification With Spectropolarimetric Lidar, Alexander J. Watson

Theses and Dissertations

A method for characterizing unknown targets using a hyperspectral polarimetric light detection and ranging (LiDAR) system is presented. Light reflected from manmade objects tends to be more polarized than light reflected from objects in the natural world. As such, polarization measurements can be used in remote sensing applications to differentiate artificial and natural objects. Previous works have attempted to characterize objects through passive polarimetric imagery. Methods developed by Cain and Lemaster and Cunningham facilitate reconstruction of the Stokes Vector from returning light. Martin used multispectral polarimetry to classify targets when the angle of incidence (AOI) is close to 0º. Here, …

An Analysis Of Hardware Modification Cost: A Test Of A 1:1 Ratio Heuristic, Oluwasegun Faleye

Theses and Dissertations

Accurate cost estimation for Department of Defense (DoD) hardware modification programs remains a critical challenge due to the complexity of Group A and Group B modifications and their associated installation costs. This study evaluates the validity of a 1:1 ratio heuristic, which suggests that Group A modification kits combined with installation costs should equate to the costs of Group B modification kits. This study analyzes cost relationships across system types and modification categories using a dataset of 255 modification programs from the Air Force Life Cycle Management Center (AFLCMC). Statistical methods, including means tables and regression modeling, evaluate the validity …

Quantum Ghost Imaging Through An Atmospheric Turbulence Simulator, Mikaela R. Morris

Theses and Dissertations

The use of single photons and photon pairs has become a cornerstone for new developments in the sensing and imaging community for their ability to improve image resolution and signal to noise readings in low light environments and large standoff distances. Quantum imaging techniques have an ability to overcome the fundamental limits of classical imaging, like diffraction. Quantum ghost imaging, a specific type of quantum imaging, uses a bi-photon pair produced during the process of spontaneous parametric down conversion to produce an image. The pair is split using a beam splitter, the signal photon is transmitted through an aperture and …

Reflected Laser Light As A Diagnostic Insight For Femtosecond Laser-Plasma Coupling, David S. Stiles

Theses and Dissertations

High-energy laser technology is critical for military, scientific, and industrial applications, but traditional mixed-radiation facilities are hindered by cost, scheduling constraints, and lack of portability. A high-repetition-rate, cost-effective alternative is needed to meet evolving application needs and timelines. This study investigates changes in reflected laser intensity to diagnose coupling efficiency and optimize energetic particle generation in ultraintense laser-target interactions. Using an ultraintense 35 femtosecond, 9 - 12 mJ laser and a deuterated water target, reflected laser light was captured via high-resolution imaging, while energetic electron and X-ray data were collected using a custom spectrometer and ion chamber, respectively. Statistical analysis …

Implications Of Magnetic Evolution On Coronal Loop Thermal Variation Prior To Solar Flares, Kara L. Kniezewski

Theses and Dissertations

Solar flares are intense bursts of electromagnetic radiation, which occur due to a rapid destabilization and reconnection of the magnetic field. While flares are a magnetic phenomena, very little attention has been paid to thermal conditions in the corona prior to flare onset. This study serves as a follow-on to Kniezewski et al., 2024, where the EUV emission from coronal loops was observed to vary substantially and without any coherence between channels before 53 off-limb flares. These variations suggest multiple mechanisms within the coronal magnetic field are responsible for heating fluctuations. Here, the 3D magnetic field is modeled using a …

Universal Model Based Systems Engineering Rendezvous And Proximity Operations Mission Planner, Thomas J. Kelly

Theses and Dissertations

This thesis addresses the fragmentation and inefficiencies in current Rendezvous and Proximity Operations (RPO) mission planning by developing an integrated Model-Based Systems Engineering (MBSE) framework. The research explores the design and implementation of RPO missions using System Modeling Language (SysML) and Matlab-based physics simulation to improve mission planning processes. Key objectives include the standardization of mission requirement characterization, the development of evaluation criteria for mission plans, and the implementation of iterative design methods to refine RPO strategies. The study leverages the Hill-Clohessy-Wiltshire (HCW) equations for initial mission planning, incorporating rigid-body attitude control with properties generated from the physical description, and …

Heterogeneous Boid Swarm Performance Under Environmental And Neighbor Communication Link Variability, Jonathan C. Oxborrow

Theses and Dissertations

Artificial swarms are of growing interest in numerous fields and use cases. As their utilization increases drones and robots with different capabilities will be required to coordinate for task completion thus creating heterogeneous swarms. Swarm individuals generally communicate with all neighbors inside their sensor range generating a significant amount of message traffic. Previous research of a heterogeneous group in a non-physical environment has shown that restricting communication to only one neighbor of each different capability maintained performance. This work applies that finding to a heterogeneous boid swarm with the addition of varied environmental conditions. The swarm is comprised of three …

Improvement Of Microcracking And Mechanical Properties Of Tungsten Fabricated Via Laser Powder Bed Fusion Through Alloying With Reactive Secondary Constituents, William S. Mockel

Theses and Dissertations

Tungsten (W), a Group VI transition metal, possesses a number of advantageous properties, most notably its impressive mechanical performance at extreme temperatures. While tungsten's nature render traditional manufacturing methods difficult, additive manufacturing through laser powder bed fusion (LPBF) presents a promising avenue for fabricating tungsten components. However, the material’s high ductile-to-brittle transition temperature combined with the embrittling effect of impurities mean that the residual stresses imparted by LPBF result in microcracking in tungsten, degrading its usefulness. This study sought to improve the characteristics of LPBF-W through the removal of embrittling oxygen content via alloying with low concentrations of reactive elements, …

Two-Key Dependent Permutation (Tkdp) And Its Applications In Information Security, Arulmani K

Theses and Dissertations

Two-Key Dependent Permutation (TKDP) algorithm for generating permutation sequences of fixed sizes, TKDP based Symmetric Block Cipher (TKDPSBC) and TKDP Audio encryption are being proposed in this thesis. TKDP algorithm is capable of generating different sequences for different key pairs. This makes it suitable for constructing dynamic S-boxes and P-boxes that have more degree of randomness and non-linearity to resist cryptanalytic attacks. Rigorous statistical tests validate the efficacy of the generated permutation sequences, affirming their suitability for cryptographic applications in conjunction with Fiestel network-based block ciphers. TKDPSBC encrypts a plaintext block into a ciphertext block of the same size. TKDP …

Fatigue Behaviour Of Al 6063 Alloy In Heat Treated, Deep Cryogenic Treated And Equal Channel Angular Pressing (Ecap) Processed Conditions, Sreearravind M

Theses and Dissertations

This research focuses on improving the Low Cycle Fatigue (LCF) life of Al6063 using three different processing techniques – Heat Treatment (HT), Deep Cryogenic Treatment (DCT), and Equal Channel Angular Pressing (ECAP). Al 6063, widely used in structural applications, has limited fatigue performance, necessitating the exploration of advanced processing techniques to enhance its LCF life.

In HT phase, Al 6063 T5 samples were subjected to solid solution HT followed by air and water quenching. The air-quenched (T6A) and water-quenched (T6W) samples were subjected to precipitation hardening. The Ultimate Tensile Strength (UTS) of the T6A sample increased to 188 MPa from …

Numerical Analyses Of Construction Materials At Different Scales For Improved Resilience And Sustainability Of Civil Infrastructures, Chenchen Huang

Theses and Dissertations

The resilience and sustainability of civil infrastructure are fundamental to supporting modern society in the face of growing environmental challenges and resource limitations. This study aims to use multi-scale numerical tools to evaluate mechanical performance of different construction materials under various environmental and loading conditions. Firstly, we adopt the discrete element method (DEM) to evaluate the influence of freeze-thaw cycles (FTCs) action on the mechanical properties of rock from the micro perspective. A simplified plastic model is proposed to capture the residual deformation produced during FTCs. To further explore the deterioration of FTCs on rock, the water-contained grain-based model (GBM) …

Nature-Based Education As A Learning Tool: Unleashing The Power Of Nature-Based Education In Egyptian Primary Schools. "The Effects Of Outdoor Learning And Open-Air Classrooms On Primary School Students In Egypt.", Nermeen Bekhiet

Theses and Dissertations

When learning modalities are tailored to each student's preferences and needs, academic success follows. This effect is contingent upon both individual and surrounding factors. Many schools in Egypt and the Middle East do not concentrate on how exposure to nature and nature-based learning can affect how the learner perceives his or her learning area. Most schools in Egypt have no exposure to nature to allow students to explore the world in their way; there is no room for diverse students to excel. Therefore, this exploratory research aims to reestablish a connection between private primary school students and the natural world …

Filipino American Parents' Experiences With The United States Special Education System: A Qualitative Study, Greyagail Custodio Surio

Theses and Dissertations

While there have been studies on Asian American (AA) parents' experiences with the U.S. special education (SPED) system, there have been no studies on Filipino American (FA) parents' experiences with the SPED system. As FAs are the third largest Asian group in the United States., there is a need for special education research to be conducted with this population. Interpretative phenomenological analysis (IPA) interviews were conducted over Zoom with FA parents of children receiving SPED services. Participants resided in various states in the United States (n = 10). Participants reported varied and nuanced experiences related to advocacy, working with the …

Social Media’S Influence On Anti-Sexual Harassment Policies In Egypt (2014-2024)900, Yasmine Elleithy

Theses and Dissertations

The study examined the role of social media and women’s online activism in the development of anti-sexual harassment policies in Egypt, specifically from 2014 to 2024. Through employing a qualitative research method involving semi-structured, in-depth interviews, the study engaged different actors, including members of the parliament, the National Council for Women, female online activists, and women’s rights specialists. During this time frame, there has been a remarkable shift in the political, social, and legislative landscape, marked by significant restrictions on traditional activism and the enactment of laws addressing sexual harassment. Throughout this period of unprecedented changes, social media has emerged …

The Role Of Non-Coding Rnas As An Innovative Therapeutic Tool For Hepatocellular Carcinoma, Nabila Mohamed Hosni El Kramani

Theses and Dissertations

Hepatocellular carcinoma (HCC) is the second lethal cancer worldwide, with over 60 million new patients added annually. Hepatitis B infection and toxins, e.g., aflatoxin, contribute to the incidence of HCC. Egypt and China show the highest prevalence of viral hepatitis and HCC in the world.

Long non-coding RNAs (lncRNAs) are non-protein-coding transcripts larger than 200 nucleotides. These transcripts work at the transcriptional, post-transcriptional, and epigenetic levels to regulate gene expression by interacting with various biomolecules, such as RNA, DNA, and proteins. They serve essential functions in chromatin remodeling and cell survival, differentiation, and proliferation. The role and biological interactions of …

Locked Gates: Japan’S Immigration Quandary In The Face Of Economic And Demographic Realities, Merna Karam Emara

Theses and Dissertations

This study explores Japan's reluctance to accept labor immigrants in the post-World War II era through the analytical lenses of identity politics and historical institutionalism. It examines how Japan’s national identity, emphasizing ethnic homogeneity and cultural preservation, has shaped restrictive immigration policies despite its economic need. Historical institutionalism provides a framework for understanding the persistence of these policies, which are rooted in the institutional legacies of Japan's post-war reconstruction. The research investigates the interplay between identity-based motivations and the institutional structures that constrain policy changes, highlighting how these dynamics have led to the exclusion of foreign labor despite the country’s …

Incorporating Sustainability In Facility Layout Planning Algorithms And Assessing Hybridization Techniques On An Egyptian Case Study, Islam Atia

Theses and Dissertations

Due to the growing consequences faced as a result of global warming and climate change; humanity has come together to take an inclusive stance to combat this serious phenomena and work towards a more sustainable future. Large amounts of carbon dioxide emissions are a major contributor to global warming, and a vast proportion of this emission come from industrial and commercial facilities. Hence, if industrial facilities are built with a larger focus on carbon footprint, it will yield a significant reduction in global emissions throughout the lifetime of the facility and will constitute a huge milestone in the journey to …

“I Remember It...I Feel It” Place’S Intangible Identity: Explorations Through The Lens Of Micro-Phenomenology- Case Study Of Al-Sultan Hassan Complex, Sarah Mohamed El Zoheiry

Theses and Dissertations

In today’s contemporary architecture, the growing of anonymous and interchangeable spaces has diminished the distinctive character of the place, its individuality and experiential signification, fostering placelessness. This research argues that the framework of reconsidering place’s atmosphere offers a pathway to reconnect people with places through emotional, sensory, and embodied encounters. This research investigates the phenomenology of place, focusing on the atmosphere as an intangible identity that transcends physical attributes and engages people's senses and feelings. By exploring the Al-Sultan Hassan complex, the study deepens the understanding of the transcendental quality of the atmosphere, it’s unfolding over time, and it’s associated …

Like A Fish Outside The Sea: An Ethnographic Exploration Of Why And How Young Lebanese From El-Mina Migrate To Europe, Lea Farida Studer

Theses and Dissertations

Following the Thawra in 2019, Lebanon’s initial optimism for political change has given way to a harsh reality. The country, troubled by hyperinflation, deteriorating state services, and worsening living conditions, coupled with corruption and sectarianism, is seeing an increasing number of Lebanese seeking alternative futures abroad, including in Europe. Be it via regular or irregular pathways, young Lebanese adults have been leaving the country, their families, their friends – their homes.

This ethnographic Master’s thesis, which was conducted during the Summer of 2023 in El-Mina, a port city in northern Lebanon, delves into the aspirations and capabilities that drive young …

From Home To Abroad: The Intergenerational Impact Of Household Member Migration On Women’S Economic & Social Empowerment In Egypt, Menna Elgohary

Theses and Dissertations

This thesis investigates to what extent the migration of a household member to an Arab country leads to increased social and economic empowerment among Egyptian women of two age categories (15-35 and +35) over two waves. Determined through Principle Component Analysis (PCA) of panel data from Egypt Labor Market Panel Surveys in 2018 and 2023, composite indices of social and economic empowerment serve as dependent variables in an IV 2SLS regression model. The model assesses whether household member migration, proxied by migration prevalence on the district (qism) level as an IV, causes a significant increase in social and economic empowerment …