Naval Postgraduate School
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JAPAN: THE SIXTH EYE?
Get PDFAs China and North Korea aggressively assert their growing capabilities and destabilize the Indo-Pacific region, Japan and other like-minded nations are considering various options to confront the growing threat. Thus, Japan has recently begun to strengthen its military cooperation with the United States, the United Kingdom, Australia, New Zealand, and Canada, all of which are members of the Five Eyes (FVEY) intelligence-sharing group. Extensive intelligence cooperation, however, has continued to lag between Japan and the FVEY members.This thesis therefore examines the factors that have prevented Japan from pursuing a deeper intelligence-sharing relationship with FVEY and whether they remain as obstacles to Japan’s formal ascension to the most extensive and exclusive intelligence-sharing group as a Sixth Eye. The research suggests that three independent variables affect Japan’s intelligence-sharing relationships: 1) increased threat perception, 2) strengthened intelligence institutions, and 3) increased trust with its security partners. Further analysis of these variables reveals that they all affect intelligence sharing differently across time periods. Changes in certain independent variables may not produce noticeable increases in intelligence sharing until decades later. As such, research has shown that Japan’s lack of sufficient institutional protections regarding state secrets remains the primary obstacle to its ascension to FVEY as a sixth member.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisMajor, United States Marine Corp
HIGH SCHOOL PRIORITY PREDICTIVE ANALYSIS FOR MARINE RECRUITER PROSPECTING ACTIVITIES
Get PDFPublic high schools across the nation play a pivotal role in the Marine Corps’ recruitment strategy. Recruiting station (RS) commanders are responsible for ensuring that recruiters have equitable access to a range of high-priority schools for their prospecting efforts. In the context of recruiting, “priority” denotes the level of time and resources a recruiter allocates to a particular school in comparison to the others in his or her area of responsibility. Because the variance in the number of annual contracts achieved in a high school is highly dependent on the effort made by the recruiter assigned to that high school, all initial efforts should be made to identify the most significant factors that contribute to contract generation, not including recruiter effort. Regression and classification modeling are potential models that may identify significant predictor variables in determining the number of contracts a high school can produce. Combined with the actual prioritization data of high schools as pulled from the Marine Corps Recruiting Information Support System (MCRISS), measuring accuracy of high school priority through classification using predictors variables can give RS commanders two products: 1) a baseline prioritization of high schools from a pure data perspective, and; 2) a comparison of predicted priority to selected priority for Fiscal Year 2023. The outcome is an optimized application of recruiter effort to the most productive schools.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine Corp
DESIGN, CONSTRUCTION, AND FLOW SIMULATION OF A MACH 5+ HYPERSONIC WIND TUNNEL
Get PDFWith substantial interest in the development of hypersonic weapon systems and reentry vehicles, wind tunnels are a crucial asset when validating computer simulations and iterating designs in a cost-effective manner. The significance of a wind tunnel is shown in this paper by testing a reentry vehicle at hypersonic speeds, simulating the body re-entering atmosphere. The wind tunnel could be used to validate computer simulations that determine the shock behavior and where significant aerodynamic pressures occur. This thesis focuses on the design and construction of a Mach 5+ hypersonic wind tunnel in Naval Postgraduate School’s Gas Dynamics Lab. The paper first covers the wind tunnel’s test section design process and predicts metrics using existing wind tunnel components through computational fluid dynamic simulations. The structural strength of the design is also evaluated using a finite element analysis simulation. The design of each test section component is also detailed, along with the tunnel construction process. The process for coding a PID controller for the air supply valve is described, along with the instructions for operation. The process of validating a prototype reentry vehicle’s computational fluid dynamic simulation using the current Mach 4.0 is then discussed. Finally, the project status is detailed with future work that can continue Naval Postgraduate School’s efforts to have a Mach 5+ hypersonic wind tunnel.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
LIMITATIONS OF SYNTHETIC APERTURE RADAR RECONSTRUCTION OF FALSE TARGETS VIA DECEPTIVE JAMMING SIGNALS
Get PDFThis research employs MATLAB to explore the limitations of deceptive electromagnetic warfare (EW) operations for injecting false targets against synthetic aperture radar (SAR) systems. Military SAR systems utilizing spotlight mode are an effective way of determining location and identification of targets; thus, the demand for jamming SAR by electronic attack (EA) is high. Deceiving a SAR system by convolving false target’s data with intercepted signals through digital radio frequency memory (DRFM) in near real-time has been studied and simulated with an assumption of perfect knowledge of a target system. However, the accurate estimation of intrinsic parameters is difficult because intercepted waveforms include little clue of intrinsic parameters; therefore, we establish restricted environment simulations to clarify the conditions of successful reconstruction of false targets and to determine the key intrinsic parameters for the SAR image formation via the range stack algorithm featuring error-free truncation, approximation, and non-interpolation. The results show that the preconfigured size of the target scene and synthetic aperture parameters are critical. Furthermore, deceptive jamming can be challenging due to the difficulty of estimating intrinsic parameters, and unique noise shapes reconstructed by corrupted false targets may alert adversaries under jammed conditions. Further studies by other algorithms and investigations of processed signals in the system are deferred.Distribution Statement A. Approved for public release: Distribution is unlimited.Outstanding ThesisSantö Kaisa, Japan Maritime Self-Defense Forc
THE IMPACT OF ATHLETIC PROGRAMS ON THE ATTRIBUTES OF NAVAL ACADEMY GRADUATES
Get PDFEvery Midshipman's experience at the United States Naval Academy (USNA) is unique but they all share the common goal of graduating and commissioning. Along with that goal, it is implied they will be good leaders of Sailors or Marines. In the USNA Strategic Plan for 2030, the Naval Academy identifies ten core attributes the school seeks in graduates. According to the 2030 Plan, these attributes include selfless, professional, inclusive, resilient, adaptable, learned, courageous, honorable, articulate, and innovative. Complementing these leadership attributes, Midshipmen are expected to develop broader leadership competencies, skills, and abilities to exercise during their service in the Navy or Marine Corps. Each Midshipman works toward cultivating these leadership attributes and leadership competencies in a different way, one of which can be participation in varsity sports. This study examined the difference in self-perceived levels of performance on the USNA leadership attributes and competencies between varsity athletes and non-varsity athletes. Results indicate there is a statistically significant difference when pairing varsity and club athletes together and comparing their data to non-varsity and non-club athletes. Based on these results, the authors provide actionable insight into the influence of varsity athlete status on the cultivation of leadership attributes among midshipmen.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine CorpsCaptain, United States Marine Corp
DEEP LEARNING METHODS FOR DECENTRALIZED DECISION-MAKING IN COUNTERSWARM ENGAGEMENTS
Get PDFThe adoption of unmanned technologies has spurred multidisciplinary research into robotic swarm systems, especially in military contexts. Inspired by biological swarms' problem-solving abilities, these systems offer the advantage of global behavior emerging from local interactions, reducing reliance on centralized control. Traditional approaches to creating emergent behavior in robotic swarms require predictable and controllable swarms with well-defined local rules and complete knowledge of all agents. In counter-swarm engagements, swarm systems need a global strategy that is robust and adaptable to dynamic environments with minimal reliance on complete knowledge. This research investigates an inverse problem: designing local rules to approximate emergent behavior typically based on perfect knowledge and communication by each drone. The objective is to create decentralized regions where a defender drone utilizes a neural network model trained extensively on simulation data. The data, extracted from engagements involving three attackers and one defender, was organized into various input sets representing different features. Post-training regression analysis identified the feature set that generated optimal defender heading angles compared to an oracle algorithm. The results demonstrated that the neural network model optimizes for shorter engagements more effectively than the oracle, validating the feasibility of employing trained networks in lieu of traditional algorithms.Distribution Statement A. Approved for public release: Distribution is unlimited.Captain, United States Marine Corp
IMPROVED PATH AND ROUTE FILTERING TO OPTIMIZE EABO CONNECTOR EMPLOYMENT
Get PDFThe United States Marine Corps requires time-efficient, accurate modeling tools to inform decision makers on how to meet logistical requirements while conducting Expeditionary Advanced Base Operations. This concept relies heavily on small, independent forces that can conduct maritime operations, command and control, and littoral combat operations within contested environments. The Marine Corps currently utilizes a heuristic model known as the Strategic Marine Analytical Solving Heuristic (SMASH) as well as the Path and Route Mixed Integer Program (PRE-MIP) optimization model, which is a reformulation of the previously used Path Enumeration Mixed Integer Program (PE-MIP), to configure solutions while analyzing logistic networks. The PRE-MIP model works by selecting a path for each piece of cargo to transit the network, and a route for each vessel to take. While each of these models are capable of producing solutions, the SMASH model produces unreliable solutions due to its heuristic nature and the PRE-MIP model cannot reach an optimal solution within a reasonable amount of time for large instances. This thesis aims to reduce computation time by first solving the linear program relaxation of PRE-MIP, then discarding those paths and routes that were not heavily utilized in the linear program. This results in a filtered path and route instance, which is much easier to solve as a mixed integer program.Distribution Statement A. Approved for public release: Distribution is unlimited.Captain, United States Marine CorpsNPS Naval Research ProgramThis project was funded in part by the NPS Naval Research Program
IMPACTS OF RIVER MIGRATION ON BEACH ELEVATION GROWTH
Get PDFCarmel River State Beach is a dynamic littoral system intermittently connecting the Carmel River and Carmel Lagoon to Carmel Bay by means of environmental forcing. When precipitation falls, lagoon water levels rise and link the river to the bay through breaching. As precipitation rates decrease and lagoon water levels fall, ocean waves push sediment onto the beach and cause a closure event which seals the river off from the bay. Usually, these breaching and closure events occur on the southern end of the beach. However, in 2023, the closure of the river mouth occurred on the north end of the beach. This presents an opportunity to understand how an anomaly like this will affect future breaching and closure events, rates of beach growth, and impacts to coastal erosion. This work hypothesizes that beach berm growth can be predicted by an empirical model relating to berm height and wave runup. It is further hypothesized that closure during seasonal dry periods evolves more slowly than during intermittent breach/closure events. GPS survey data is used to quantify the change in beach morphology using a dataset from 2020 to present with a focus on the anomalous northern closure event of the Carmel River in 2023. It was found that the empirical model can be calibrated with root-mean-square errors of 25 cm, but that calibration constants must be periodically adjusted. Better quantifying beach recovery to breaching events is essential to ensure success for ship-to-shore operations.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav
JAPAN’S MILITARY REAWAKENING: TOKYO’S DEFENSE MODERNIZATION DURING 2006–2023
Get PDFThis thesis seeks to answer a key question: What are the core drivers of Japan’s military modernization from 2006–2023? This thesis analyzes defense policy documents, economic data, and domestic public opinion towards military modernization efforts over the past two decades. It finds three main drivers: rising threat perception toward the People’s Republic of China (PRC) and Democratic People’s Republic of Korea (DPRK), Japanese domestic opinion towards defense reforms becoming more favorable, and supportive leaders like Prime Ministers Abe and Kishida who pushed forward defense reforms. These factors contributed to significant developments in Japan’s military modernization, such as increased defense spending and improvements to missile, air, and naval capabilities. By understanding the core drivers of Japan’s defense modernization, the U.S. can more accurately understand how the Japan Self Defense Force (JSDF) will continue to contribute to the U.S.-Japan alliance and how the U.S. may better support Japan’s security needs.Distribution Statement A. Approved for public release: Distribution is unlimited.Major, United States Marine Corp
BAYESIAN TRANSFER LEARNING FOR PASSIVE SONAR TARGET CLASSIFICATION
Get PDFPassive sonar data contains valuable acoustic signatures that can be used in ship detection tasks. However, challenges arise in machine learning applications when datasets are too noisy or difficult to label. Furthermore, neural networks often lack explainability metrics to justify their predictions. In this work, we construct a framework for developing Bayesian classification models using transfer learning to detect ship presence in a given passive sonar spectrogram. We apply a ResNet54 architecture with checkpoints pretrained on the AudioSet dataset toward developing MC Dropout and Flipout Reparameterization models for passive sonar ship detection. By conducting uncertainty analysis leveraged through the Bayesian architecture, we show that our models are well calibrated and thus have improved explainability. Furthermore, models leveraging transfer learning attain comparable or improved performance metrics to models trained from scratch but do so in less training time, thus reducing costs of model production and fine-tuning.Distribution Statement A. Approved for public release: Distribution is unlimited.Ensign, United States Nav