Naval Postgraduate School
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Self-Sealing Hose
No full textA self-sealing hose includes an inner rubber layer comprising a first rubber material; and an outer rubber layer comprising a second rubber material. The second rubber material has an ultimate strain of at least 100% and an elastic limit of at least about 7 MPa. The first rubber material has a modulus measured at 250% elongation of less than about 10 kPa
IMPROVED GRAPHENE-ALUMINUM MIXING FOR COLD-SPRAY APPLICATIONS
No full textGiven the heavy fiscal and operational costs posed to the United States Navy by corrosion, anticorrosive surface coatings have potential to greatly benefit the fleet. To develop such a coating, it is hoped that graphene, a hexagonal planar lattice of carbon atoms, may be leveraged for its high strength, chemical inertness, and hydrophobic characteristics. This could potentially be achieved through the cold spray application of an aluminum metal matrix composite using graphene as a filler. Unfortunately, the chemical inertness and hydrophobicity that make the material attractive also make the dispersion of graphene a major technical challenge. Since graphene does not dissolve in water, alternative solvents or tertiary surfactants must be used to create a homogenous distribution of graphene throughout the aluminum matrix. Additionally, graphene possesses a tendency to agglomerate due to interlayer van der Waals forces, which necessitate the exfoliation of agglomerations by applying shear force to the agglomerates throughout the suspension in order to prevent stress concentrators. A simple method to disperse graphene and aluminum was tested using a variety of different parameters and evaluated through electron microscopy in hope of establishing a reliable process for producing a composite graphene-aluminum powder that could act as a cold spray feed powder for anticorrosive surface protection in the marine environment.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
ASSESSMENT AND VALIDATION OF TESLA VALVE DESIGN FOR HYDRAULIC FLOWS
No full textThis thesis investigates the performance of various Tesla valve geometries as passive flow control devices for potential use in naval fluid systems. Tesla valves exhibit diodicity, directionally dependent resistance to fluid flow, without the need for moving parts, offering advantages in reliability and compactness. The U.S. Navy currently employs large, weighty flow-regulating devices such as the Cascade Orificial Restriction Device (CORD), which could benefit from miniaturized, additively manufactured alternatives. Motivated by the Navy’s growing interest in additive manufacturing, this study explores the feasibility of replacing traditional flow-regulating devices with Tesla valve configurations. A comprehensive review of literature highlighted the wide applicability of Tesla valves and the concept of diodicity, from microfluidic systems to passive cooling in nuclear reactors and hydrogen decompression. Both computational fluid dynamics (CFD) and experimental methods are used to evaluate diodicity across various Reynolds numbers and geometries. Validation and verification (V&V) principles are applied to analyze model fidelity. The goal was to determine whether Tesla valves could match or exceed the performance of existing flow-regulation technologies, while reducing size, weight, and manufacturing complexity, ultimately enhancing the Navy’s onboard fluid system capabilities and supporting future advances in passive flow control.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
CYBER ORCHESTRATION: AUTOMATING NETWORK DETECTION AND RESPONSE
Full text linkAs cyber threats grow in scale and sophistication, the ability to rapidly detect and respond to malicious activity across distributed networks is essential. This thesis introduces a centralized orchestration framework that automates defensive measures in response to real-time events, beginning with host-based alerts but designed to incorporate diverse data sources. The system builds on the Layer 4.5 orchestration framework to enable dynamic deployment of security modules and policy enforcement without interrupting host operations. Integrated with tools such as Ansible and iptables, the orchestrator can deploy countermeasures including kernel modules and host isolation scripts. By correlating alert patterns across multiple hosts, it enables timely, consistent, and scalable network-wide responses with minimal operator input. Experimental validation demonstrates how the orchestrator can contain attacks such as DNS floods and suspicious outbound connections by deploying tailored mitigation modules and verifying enforcement across network segments. Although this work references Cyber Protection Condition (CPCON) levels as a use case for structured escalation, the orchestrator’s flexible architecture supports broader applications in both military and civilian network environments. This research contributes a practical, extensible solution for accelerating cyber defense through automation, reducing human workload, and enhancing situational awareness at the operational edge.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant, United States Nav
Faces of NPS: Ying Zhao, PhD
No full textFaces of NPS features interviews spotlighting the students, faculty, staff and alumni of our Nation's premier defense education and research institution
Math Acceleration Lab at NPS Strengthens Calculus Foundations Through Personalized Mentorship
No full textOPEN-WORLD VIDEO STREAM FINGERPRINTING
No full textNetwork traffic fingerprinting threatens the security and privacy of streaming video on the web, but there are questions about its effectiveness that we aim to answer through more rigorous testing. We first collect a novel dataset to support both our own investigation and the work of future researchers. We then test the existing video stream fingerprinting approach in larger and more realistic open-world scenarios, followed by a variety of more advanced techniques drawn from the literature on open set recognition, out-of-distribution detection, and robustness to adversarial examples. Our contributions include the dataset and a number of findings. We find that: fingerprinting can pose a compelling threat even when users stream video over Tor; however, even with a modest open-world recall goal, the base rate problem would make the existing approach ineffective at the scale of the largest platforms hosting hundreds of millions or more videos; combinations of more advanced techniques can substantially reduce the open-world false positive rate compared to the baseline, but introducing two other dimensions of realism can greatly increase the false positive rate even when closed-world accuracy remains near perfect. Accordingly, we call for future work to focus primarily on large open-world scenarios, rather than small closed-world scenarios, building on our approach to measuring and reasoning about the effectiveness of fingerprinting at scale.Distribution Statement A. Approved for public release: Distribution is unlimited.Lieutenant Colonel, United States Arm
REBALANCING RETENTION: ORGANIZATIONAL SOLUTIONS FOR THE MARINE CORPS CAREER PLANNING PROGRAM
No full textThis thesis investigates the structural and organizational challenges facing Marine Corps Career Counselors and the Career Planning Program amid increasing enlisted retention demands following the publication of Talent Management 2030. Using a grounded analysis approach, the research analyzes data from 25 in-depth interviews conducted with active-duty Career Counselors across multiple billet types to identify key drivers of performance and systemic barriers within the Career Planning Program. This research informs the development of the Human Performance Drivers framework with two core dimensions: Workload Management and Resource Allocation, and a Systematic Approach to Retention. The analysis findings reveal a disconnect between growing performance expectations and available institutional support, including staffing, training, and administrative resources. To identify actionable recommendations, the thesis conducts a comparative case analysis of the Marine Corps’ recruiting and retention structures, highlighting transferable practices from Marine Corps Recruiting Command that may enhance the Career Planning Program.Distribution Statement A. Approved for public release: Distribution is unlimited.Gunnery Sergeant, United States Marine Corp
A FRAMEWORK FOR MODEL-BASED SYSTEM ENGINEERING AND COMPUTATIONAL FLUID DYNAMICS INTEGRATION: DATA EXCHANGE AND ONTOLOGY ALIGNMENT
Full text linkDigital Engineering (DE) has become a field of growing interest in order to help integrate various system engineering processes. The integration effort provides a central solution and repository that can help track multiple requirements, technical data, engineering design, or project management changes. However, in order to successfully integrate, there must be a framework or an ontology that helps provide the relationship between different entities from different disciplines. This thesis investigated the integration of MBSE with computer-aided engineering (CAE), specifically in a CFD environment, to build on an existing ontology framework that already incorporates CAD entities. This thesis used an extensive literature review to analyze, and researched various different ontologies that have been proposed to determine which ontology aligned best with CFD elements. Extensive research was also conducted to determine the most critical CFD elements. Research was able to determine major CFD elements, mapping of those elements to the proposed CFD Simulation Intent (CFD-SI) ontology, adding entities to the lifecycle modeling language conceptual data model (CDM), identified a neutral file exchange framework, and proposed a pathway for DoD implementation. MBSE and CAE users are able to use the developed framework to continue to improve concordance and interoperability between different disciplines to achieve an authoritative source of truth (ASoT).Distribution Statement A. Approved for public release: Distribution is unlimited.Civilian, Department of the Nav