A Reverse Localization Scheme for Underwater Acoustic Sensor Networks

Underwater Wireless Sensor Networks (UWSNs) provide new opportunities to observe and predict the behavior of aquatic environments. In some applications like target tracking or disaster prevention, sensed data is meaningless without location information. In this paper, we propose a novel 3D centralized, localization scheme for mobile underwater wireless sensor network, named Reverse Localization Scheme or RLS in short. RLS is an event-driven localization method triggered by detector sensors for launching localization process. RLS is suitable for surveillance applications that require very fast reactions to events and could report the location of the occurrence. In this method, mobile sensor nodes report the event toward the surface anchors as soon as they detect it. They do not require waiting to receive location information from anchors. Simulation results confirm that the proposed scheme improves the energy efficiency and reduces significantly localization response time with a proper level of accuracy in terms of mobility model of water currents. Major contributions of this method lie on reducing the numbers of message exchange for localization, saving the energy and decreasing the average localization response time

ARCHITECTURE FOR A CBM+ AND PHM CENTRIC DIGITAL TWIN FOR WARFARE SYSTEMS

The Department of the Navy’s continued progression from time-based maintenance into condition-based maintenance plus (CBM+) shows the importance of increasing operational availability (Ao) across fleet weapon systems. This capstone uses the concept of digital efficiency from a digital twin (DT) combined with a three-dimensional (3D) direct metal laser melting printer as the physical host on board a surface vessel. The DT provides an agnostic conduit for combining model-based systems engineering with a digital analysis for real-time prognostic health monitoring while improving predictive maintenance. With the DT at the forefront of prioritized research and development, the 3D printer combines the value of additive manufacturing with complex systems in dynamic shipboard environments. To demonstrate that the DT possesses parallel abilities for improving both the physical host’s Ao and end-goal mission, this capstone develops a DT architecture and a high-level model. The model focuses on specific printer components (deionized [DI] water level, DI water conductivity, air filters, and laser motor drive system) to demonstrate the DT’s inherent effectiveness towards CBM+. To embody the system of systems analysis for printer suitability and performance, more components should be evaluated and combined with the ship’s environment data. Additionally, this capstone recommends the use of DTs as a nexus into more complex weapon systems while using a deeper level of design of experiment.Outstanding ThesisCivilian, Department of the NavyCommander, United States NavyCivilian, Department of the NavyCivilian, Department of the NavyCivilian, Department of the NavyCivilian, Department of the NavyCivilian, Department of the NavyCivilian, Department of the NavyApproved for public release. Distribution is unlimited

Environmental requirements for optimal naval operational efficiency

In this thesis the applicability of ocean environment modelling as a part of optimal naval operational efficiency, and thus military oceanography, is evaluated. To be able to do this, the principles of knowledge-based warfare and the ability to make rapid environmental assessments, are introduced. These then form part of optimal efficiency. Modelling of the environment implies knowledge-based warfare and accommodates the ability to make a rapid environmental assessment. After an overview of past and current ocean modelling (specifically wave modelling), the third generation SWAN (Simulating WAves Nearshore) model is selected to model a small component of the military oceanographic spectrum viz. waves. The selected area, includes an area where the US Navy conducted an amphibious landing exercise (Operation Laurel) during October 2001. Three case studies are considered for modelling. These included an extreme wave condition, a mode wave condition and the conditions during Operation Laurel. Data were obtained from the wave rider buoy at Slangkop near Cape Town and analysed for a specific period during 2001. In all three cases the wave dissipation and maximum energy transfer areas were determined from the model. From these, certain deductions could be made regarding the influence the environment under these three different conditions could have on naval operations in the littorals. It is concluded that ocean modelling should form an integral part of naval operational efficiency and its contribution as force multiplier should be taken into consideration

RELIABILITY AND RESILIENCE EVALUATION OF A STAND-ALONE MOBILE MICROGRID-ANALYSIS AND EXPERIMENTAL MEASUREMENTS

As the Department of Defense (DOD) deploys renewable distributed energy resources (DERs) to reduce fossil fuel consumption, microgrids are being evaluated as one way to generate and deliver reliable electric power to stationary and mobile military units. Commercial off the Shelf (COTS) microgrid components are a viable cost-effective option to setup stand-alone microgrid systems to support mobile military units and help drive the transition to a more sustainable yet energy-resilient military. Reliability and resilience are key parameters in determining the effectiveness of microgrids in supporting military missions. Although in the past few years many researchers have presented reliability and resilience models of various complexity, experimental measurements and model validation are not available in the literature for mobile COTS microgrids. The goal of this thesis research is to experimentally assess the reliability and resilience of stand-alone, mobile microgrids that can be carried by one or two individuals and can be easily assembled in the field in support of operations in locations where utility power is not available. Utilizing COTS DERs including batteries, PV arrays and power converters, three different standalone microgrid architectures were designed, analyzed, and tested in the laboratory. Reliability block diagrams, and system fault trees were created per MIL-HDBK-338B, to compare the reliability of the three microgrid configurations.Major, United States Marine CorpsApproved for public release. Distribution is unlimited

Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) 2019 Annual Report

Prepared for: Dr. Brian Bingham, CRUSER DirectorThe Naval Postgraduate School (NPS) Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) provides a collaborative environment and community of interest for the advancement of unmanned systems (UxS) education and research endeavors across the Navy (USN), Marine Corps (USMC) and Department of Defense (DoD). CRUSER is a Secretary of the Navy (SECNAV) initiative to build an inclusive community of interest on the application of unmanned systems (UxS) in military and naval operations. This 2019 annual report summarizes CRUSER activities in its eighth year of operations and highlights future plans.Deputy Undersecretary of the Navy PPOIOffice of Naval Research (ONR)Approved for public release; distribution is unlimited

Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) 2019 Annual Report

Prepared for: Dr. Brian Bingham, CRUSER DirectorThe Naval Postgraduate School (NPS) Consortium for Robotics and Unmanned Systems Education and Research (CRUSER) provides a collaborative environment and community of interest for the advancement of unmanned systems (UxS) education and research endeavors across the Navy (USN), Marine Corps (USMC) and Department of Defense (DoD). CRUSER is a Secretary of the Navy (SECNAV) initiative to build an inclusive community of interest on the application of unmanned systems (UxS) in military and naval operations. This 2019 annual report summarizes CRUSER activities in its eighth year of operations and highlights future plans.Deputy Undersecretary of the Navy PPOIOffice of Naval Research (ONR)Approved for public release; distribution is unlimited

Advancing Climate Change Research and Hydrocarbon Leak Detection : by Combining Dissolved Carbon Dioxide and Methane Measurements with ADCP Data

With the emergence of largescale, comprehensive environmental monitoring projects, there is an increased need to combine state-of-the art technologies to address complicated problems such as ocean acidifi cation and hydrocarbon leak detection

Summary of Research 1994

The views expressed in this report are those of the authors and do not reflect the official policy or position of the Department of Defense or the U.S. Government.This report contains 359 summaries of research projects which were carried out under funding of the Naval Postgraduate School Research Program. A list of recent publications is also included which consists of conference presentations and publications, books, contributions to books, published journal papers, and technical reports. The research was conducted in the areas of Aeronautics and Astronautics, Computer Science, Electrical and Computer Engineering, Mathematics, Mechanical Engineering, Meteorology, National Security Affairs, Oceanography, Operations Research, Physics, and Systems Management. This also includes research by the Command, Control and Communications (C3) Academic Group, Electronic Warfare Academic Group, Space Systems Academic Group, and the Undersea Warfare Academic Group

Aeronautics and space report of the President, 1980 activities

The year's achievements in the areas of communication, Earth resources, environment, space sciences, transportation, and space energy are summarized and current and planned activities in these areas at the various departments and agencies of the Federal Government are summarized. Tables show U.S. and world spacecraft records, spacecraft launchings for 1980, and scientific payload anf probes launched 1975-1980. Budget data are included