Naval Postgraduate School
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Faces of NPS: Lt. Col. Temesha Christensen, USAF
Get PDFFaces of NPS features interviews spotlighting the students, faculty, staff and alumni of our Nation's premier defense education and research institution
BEYOND THE DETERMINISTIC: A STOCHASTIC EXTENSION TO THE MARINE CORPS ADVANCED PRODUCTION PLAN MODEL (MCAPPM)
No full textIn March 2025, the Marine Corps Advanced Production Plan Model (MCAPPM)—a fixed inventory Markov model aimed at increasing the United States Marine Corps (USMC) production plan accuracy—was published as an NPS thesis by Captain Brian Riddle USMC. Riddle (2025) concluded the MCAPPM is deterministically more accurate than legacy production planning methods. This thesis introduces historically informed, stochastically varying state transition rates to conduct the Monte Carlo simulations required to validate MCAPPM accuracy. By comparing Fiscal Year 2018 historic planned production against MCAPPM 95% prediction intervals, this thesis concludes that historic and MCAPPM production values are different for 124 of 128 Military Occupational Specialties analyzed. MCAPPM is determined to be more accurate than historic planned production with mean absolute percentage error values of 17.4% and 30.1% respectively, indicating Markov attrition modeling may improve modeling accuracy in practice. MCAPPM forecasting is then introduced as a visual and analytical aid when comparing MCAPPM five-year forecasts against forecast inventory requirements set forth by HQMC. This thesis recommends additional research to determine the influence historic planned and executed production differences have on MCAPPM accuracy. Additionally, to fully validate the claimed accuracy of MCAPPM, Markov methods require comparison to legacy methods within current USMC modeling environments.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine CorpsNPS Naval Research ProgramThis project was funded in part by the NPS Naval Research Program
Method, System and Apparatus for Spacecraft Attitude Control Error Reduction in Trajectory Interpolation
No full textA method, apparatus and system for controlling an attitude of a spacecraft, the spacecraft including an attitude control system operatively associated with a ground-based spacecraft control system. According to an exemplary embodiment, the spacecraft attitude control system uses B-spline interpolator for commanding the spacecraft and a Kalman filtering process is used to estimate B-spline interpolator coefficients. The methods and systems disclosed herein can be implemented in, for example, executable machine code and/or integrated circuit hardware
Faces of NPS: Cmdr. Frode Mjelde, Royal Norwegian Navy
No full textFaces of NPS features interviews spotlighting the students, faculty, staff and alumni of our Nation's premier defense education and research institution
LOCAL RHEOLOGY OF DENSE GRANULAR FLOWS WITH MIXED GRANULAR TEMPERATURE GENERATION
No full textThis thesis investigates proposed constitutive laws for dense granular flows using particle-based simulations of planar shear under varying stress conditions. Granular materials are prevalent in both science and industry, yet a fully local relationship between stress and strain rate remains elusive. A widely used model links the stress ratio to a dimensionless shear rate, but it breaks down in slow-flowing regimes, predicting no motion where deformation persists. Nonlocal models incorporating a diffusive fluidity parameter can resolve this issue in certain geometries. Alternatively, local models grounded in kinetic theory that incorporate granular temperature—a measure of grain velocity fluctuations—also show promise.To evaluate these models, we simulate flows with stress gradients induced by gravity and mechanical vibration, producing granular temperature under mixed driving conditions. Our findings yield four primary conclusions. First, the fluidity-based model does not collapse well, particularly under mechanical vibration. Second, a granular temperature-based model more accurately reproduces flow behavior in both vibrated and mixed cases. Third, packing fraction, though often treated as fundamental, is not a controlling variable in these formulations. Finally, observed stress and temperature anisotropies suggest that modeling granular temperature through kinetic theory may be more complex than previously anticipated.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisCaptain, United States Arm
SHIP-CONFINED SYSTEM BLUEPRINT FOR ENHANCING NAVAL SUSTAINMENT THROUGH EMERGING MANUFACTURING CAPABILITIES.
No full textThis thesis explores the operational integration of additive manufacturing (AM) in support of Military Sealift Command (MSC) missions. It investigates the logistical and technical challenges that hinder effective AM use in afloat environments and identifies pathways to enhance resilience and material readiness. Drawing on qualitative methods, including direct operational experience aboard naval platforms, survey data from MSC AM users, and systems engineering tools, this research evaluates the current state and future potential of AM at sea. The findings support a hybrid implementation model that combines onboard AM personnel trained in production with a parts repository and access to shore-based design and engineering expertise, with the goal of ultimately establishing independent production facilities. This research aims to elicit problems associated with part replacement and to identify leverage points to reduce dependence on traditional supply chains, with the objective of extending the operational reach during contested or expeditionary missions. The conclusions and recommendations contribute to a broader understanding of how AM can be institutionalized, improve compatibility with current naval logistics architecture, and align with evolving concepts such as distributed maritime operations, contested logistics, and stand-in forces. This study offers a ship-confined system blueprint approach for enhancing naval sustainment through emerging manufacturing capabilities.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisMajor, United States Marine Corp
Faces of NPS: Lt. Cmdr. James Phan, USN
No full textFaces of NPS features interviews spotlighting the students, faculty, staff and alumni of our Nation's premier defense education and research institution
AI/DEEP LEARNING WAVEFRONT SENSING FOR HEL USING TARGET IMAGE TO SIMPLIFY ADAPTIVE OPTICS SYSTEMS
No full textAtmospheric turbulence significantly limits the performance of imaging and high-energy laser (HEL) systems by distorting the wavefront as it propagates through the atmosphere. Traditional correction methods use wavefront sensors with adaptive optics, which can be expensive, complex, and resource-intensive. This thesis was focused on using machine learning (ML) models to predict atmospheric turbulence parameters, to be used as another method to correct for distortion within the atmosphere. ML models could decrease the complexity normally required for systems with turbulence correction methods. This was done by conducting a transfer learning experiment with a convolutional neural network (CNN) specialized in image classification. It was modified to fit a regression problem of characterizing the Zernike polynomials corresponding to the turbulence. Large datasets of turbulent images were created, and multiple models were tested to find what parameters lead to better performance and a lower mean squared error (MSE). Ultimately, a combined turbulence model yielded superior performance at high turbulence. Also, new untested images were introduced to gauge the model’s success against unseen data. By improving on modern artificial intelligence (AI) techniques, the project aimed to enhance the Navy’s capabilities and provide a path for future turbulence correction innovation in other optics and laser systems.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisEnsign, United States Nav
MATERIAL SUBSTITUTES FOR THERMAL AND SONIC PROTECTION IN EXPERIMENTAL DIVING WETSUITS
Get PDFDiving applications within the United States Navy include, but are not limited to, wreckage salvage operations, underwater repairs, naval special warfare, and expeditionary warfare. While performing these tasks, divers are subjected to water temperatures and acoustic signals that could be incredibly harmful. However, using a silicone-based carrier polymer with embedded glass microspheres, composites were constructed and have shown improved thermal resistivity and acoustic protection when coupled with standard 3 mm neoprene wetsuits. Further modified composites were created with the use of embedded ceramic microspheres and were coupled with both the glass microspheres composite and the 3 mm neoprene wetsuits, resulting in better thermal resistivity. All previous research, however, was conducted using the same carrier polymer, Polymethylsiloxane. Therefore, we investigated both the thermal resistivity and acoustic properties of new composite materials that were fabricated with different carrier polymers with embedded glass microspheres, ceramic microspheres, and large ceramic ballistic beads, as well as combinations of all these additives. Through experimental thermal conductivity testing, a new composite material, Sylgard-527 with embedded K1 glass microspheres, demonstrated the best thermal insulation so far. Furthermore, acoustic testing indicated that the most sonically protective composite was Dowsil 3-4241 with embedded K1 glass microspheres.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
RUSSIAN AMPHIBIOUS CAPABILITIES IN THE RUSSO-UKRAINIAN WAR: AN EXAMINATION OF BLACK SEA FLEET CAPACITY AND OPERATIONAL FAILURES
No full textThe Russo-Ukrainian War has followed two distinct trajectories: maneuver-based offensives in eastern Ukraine and attritional battles along entrenched frontlines. While analysts have heavily scrutinized ground operations, naval activity in the Black Sea remains underexplored. This thesis addresses that gap by examining Russian amphibious capabilities and their limited application during the conflict. It asks: What lessons can the United States draw from the absence of significant Russian amphibious operations in the Black Sea?Using U.S. amphibious doctrine as a benchmark, this study assesses Russian doctrine and evaluates the Black Sea Fleet’s transport capacity and naval infantry organization. It analyzes operational data from February 24 to April 16, 2022 to identify constraints on amphibious action.Three key findings emerge. First, Russia failed to establish sea control in the northern Black Sea, precluding amphibious landings. Second, during the narrow window when such operations were possible, Russian naval infantry remained engaged in combat on land. Third, the Russian military demonstrated a systemic inability to conduct joint operations under wartime conditions.Future research should examine the Black Sea Fleet’s use of air assets during the early war period and compare Russian navy missile capabilities with those of the U.S. Aegis system to assess Russia’s capacity for sea control against a peer adversary.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine Corp