An opportunistic array is an integrated ship-wide digital phased-array radar, where antenna elements are placed at available open areas over the entire shipâ s length. Such an array has the potential to fulfill many of the Navyâ s missions, including ballistic missile defence (BMD) where the radar mission encompasses exo-atmospheric surveillance, tracking and preliminary discrimination. Advantages of opportunistic arrays include enhanced stealth â since low-profile antennas reduce the shipâ s RCS; high angular resolution â as the entire shipâ s length forms the â apertureâ and produces a narrow beamwidth; and potentially lower costs â through the use of COTS technology and a flexible digital antenna architecture that reduces the number of distinct radar systems required. This research first investigated the opportunistic array concept in the context of BMD. A system level tradeoff was performed to size the system and verify that detection ranges greater than 1000 km could be achieved. Next, the research focused on designing a low-profile, broad-band U-slot microstrip patch antenna. Theoretical calculations and parametric studies were performed to develop an antenna element that could operate in the upper VHF/lower UHF frequencies. A set of simple design procedures is proposed to provide approximate rules that result in a good â first-passâ design with prescribed characteristics that require minimal tuning.

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This thesis examines the potential destabilizing implications of conventional prompt global strike capabilities that operate from or through space. Existing material on this subject is largely limited to debates over the merits of terrestrial verses space basing and arguments against deployment over perceived increases in the likelihood of inadvertent nuclear war. This thesis addresses these issues, but takes the next step and analyzes the root causes and proposes possible solutions to the "security dilemma" these weapons may create. The central finding is that in order to fully exploit the predicted advantages of conventional prompt global strike capabilities, significant changes to the enduring Cold War nuclear postures of the United States and Russia are necessary.

Thesis (M.S. in Mechanical Engineering)--Naval Postgraduate School, December 2009. / Thesis Advisor(s): Yakimenko, Oleg. Second Reader: Adams, Christopher. "December 2009." Description based on title screen as viewed on January 26, 2010. Author(s) subject terms: missile guidance laws, trajectory shaping guidance, trade-offs, induced drag polar, optimal flight path, cost function, boost phase intercept, intercept geometry, time-to-intercept. Includes bibliographical references (p. 115-116). Also available in print.

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, June 2004. / Thesis advisor(s): Phillip E. Pace, Murali Tummala. Includes bibliographical references (p. 49-50). Also available online.

Thesis (M.B.A.)--Ohio State University, 1960. / Available online via OhioLINK's ETD Center

Exposure to high impact velocity is the principle limiting factor of material performance in ballistic applications for use in civilian and defense industries. Graphene has emerged as a material of scientific interest due to its exceptional mechanical and thermal properties. When incorporated appropriately in a polymer matrix, graphene can significantly improve properties of polymers at small loading, while preserving the integrity of the polymer. Graphene based polymer nanocomposites provide a novel approach for material design for ballistic applications. The reliability of graphene/polymer nanocomposites on end use applications depends on understanding the effect of structure-property relationship of nanocomposite. A first approach to engineering nanocomposite for ballistic applications requires thorough understanding of physical properties change with incorporation of nanofillers in polymer matrix. One significant class of properties tremendously affected by inclusion of nanofiller is thermodynamic properties. Therefore, a first investigative study, we explore non-linear elastic behavior of graphene using first principle method, specifically Density-Functional Theory (DFT), and atomistic simulation. Using DFT, we calculated the equation of state (EOS) and elastic constants of graphene. The results are in agreement with experimental and other theoretical studies using DFT. However, accuracy of atomistic simulations is limited by empirical potentials. Nevertheless, general anisotropic, non-linear mechanical behavior of graphene is evident on both approaches. Additionally we use molecular dynamics (MD) simulations to study effect of graphene nanofiller on thermo‑mechanical properties of polyurethane. We have calculated thermodynamic, structural and mechanical properties of the amorphous polyurethane and its graphene nanocomposite. Our results show significant enhancement of thermal-mechanical properties. The final part of this dissertation, we used non-equilibrium molecular dynamics (NEMD) simulations to investigate dynamic response behavior of polyurethane and its graphene nanocomposite. Calculation of Hugoniot states of polyurethane agrees with experimental studies. However, a phase change phenomenon observed in experimental work was not visible in the present work. This is due to bond breaking and formation, which is a clear characterization of phase changes. Graphene-polyurethane nanocomposites demonstrate similar shock wave propagation illustrating characteristics of impeding shock wave when subjected to different particle velocities. This is due to graphene inducing stress concentrations in the composite, which may increase yield strength.

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