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Design Optimization Of Solid Rocket Motor Grains For Internal Ballistic PerformanceHainline, Roger 01 January 2006 (has links)
The work presented in this thesis deals with the application of optimization tools to the design of solid rocket motor grains per internal ballistic requirements. Research concentrated on the development of an optimization strategy capable of efficiently and consistently optimizing virtually an unlimited range of radial burning solid rocket motor grain geometries. Optimization tools were applied to the design process of solid rocket motor grains through an optimization framework developed to interface optimization tools with the solid rocket motor design system. This was done within a programming architecture common to the grain design system, AML. This commonality in conjunction with the object-oriented dependency-tracking features of this programming architecture were used to reduce the computational time of the design optimization process. The optimization strategy developed for optimizing solid rocket motor grain geometries was called the internal ballistic optimization strategy. This strategy consists of a three stage optimization process; approximation, global optimization, and highfidelity optimization, and optimization methodologies employed include DOE, genetic algorithms, and the BFGS first-order gradient-based algorithm. This strategy was successfully applied to the design of three solid rocket motor grains of varying complexity. The contributions of this work was the development and application of an optimization strategy to the design process of solid rocket motor grains per internal ballistic requirements.
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TELEMETRY CHALLENGES FOR BALLISTIC MISSILE TESTING IN THE CENTRAL PACIFICMarkwardt, Jack, LaPoint, Steve 10 1900 (has links)
International Telemetering Conference Proceedings / October 28-31, 1996 / Town and Country Hotel and Convention Center, San Diego, California / The Ballistic Missile Defense Organization (BMDO) is developing new Theater Missile
Defense (TMD) and National Missile Defense (NMD) weapon systems to defend against
the expanding ballistic missile threat. In the arms control arena, theater ballistic missile
threats have been defined to include systems with reentry velocities up to five kilometers
per second and strategic ballistic missile threats have reentry velocities that exceed five
kilometers per second. The development and testing of TMD systems such as the Army
Theater High Altitude Area Defense (THAAD) and the Navy Area Theater Ballistic
Missile Defense (TBMD) Lower Tier, and NMD systems such as the Army
Exoatmospheric Kill Vehicle and the Army Ground-Based Radar, pose exceptional
challenges that stem from extreme acquisition range and high telemetry data transfer rates.
Potential Central Pacific range locations include U.S. Army Kwajalien Atoll/Kwajalein
Missile Range (USAKA/KMR) and the Pacific Missile Range Facility (PMRF) with target
launches from Vandenberg Air Force Base, Wake Island, Aur Atoll, Johnston Island, and,
possibly, an airborne platform. Safety considerations for remote target launches dictate
utilization of high-data-rate, on-board instrumentation; technical performance measurement
dictates transmission of focal plane array data; and operational requirements dictate
intercepts at exoatmospheric altitudes and long slant ranges. The high gain, high data rate,
telemetry acquisition requirements, coupled with loss of the upper S-band spectrum, may
require innovative approaches to minimize electronic noise, maximize telemetry system
gain, and fully utilize the limited S-band telemetry spectrum. The paper will address the
emerging requirements and will explore the telemetry design trade space.
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Ship Anti Ballistic Missile Response (SABR)Johnson, Allen P., Breeden, Bryan, Duff, Willard Earl, Fishcer, Paul F., Hornback, Nathan, Leiker, David C., Carlisle, Parker, Diersing, Michael, Devlin, Ryan, Glenn, Christopher, Hoffmeister, Chris, Chong, Tay Boon, Sing, Phang Nyit, Meng, Low Wee, Meng, Fann Chee, Wah, Yeo Jiunn, Kelly, John, Chye, Yap Kwee, Keng-Ern, Ang, Berman, Ohad, Kian, Chin Chee 06 1900 (has links)
Includes supplemental material. / Based on public law and Presidential mandate, ballistic missile defense development is a front-burner issue for homeland
defense and the defense of U.S. and coalition forces abroad. Spearheaded by the Missile Defense Agency, an integrated
ballistic missile defense system was initiated to create a layered defense composed of land-, air-, sea-, and space-based assets.
The Ship Anti-Ballistic Response (SABR) Project is a systems engineering approach that suggests a conceptualized system
solution to meet the needs of the sea portion of ballistic missile defense in the 2025-2030 timeframe. The system is a unique
solution to the sea-based ballistic missile defense issue, combining the use of a railgun interceptor and a conformable aperture
skin-of-the-ship radar system.
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The role of twinning in the plastic deformation of alpha phase titaniumLainé, Steven John January 2017 (has links)
The optimisation of compressor stage aerofoil and fan blade design remains an important area of titanium alloy research and development for aerospace gas turbines. Such research has important implications for critical and sensitive component integrity and efficiency. In particular, a better understanding of how deformation twinning interacts with microstructural features in titanium alloys is required, because such twinning facilitates plastic deformation at a higher strain rate than dislocations. To investigate this behaviour, commercial purity titanium and the titanium alloy Ti–6Al–4V were subjected to ballistic impact testing at room temperature with a high strain rate of 10³s⁻¹. In addition, a detailed analysis was conducted of three manufacturing processes of Ti–6Al–4V (wt. %) that are likely to cause deformation twinning: metallic shot peening, laser shock peening and deep cold rolling. The results presented in this thesis have furthered the understanding of the role of deformation twinning in the plastic deformation of α-phase titanium. Key findings of the research include the characterisation of deformation twinning types and the conditions that favour certain deformation twinning types. From the analysis of the ballistic testing of commercial purity titanium, the first definitive evidence for the existence of {112‾4} twinning as a rare deformation twinning mode at room temperature in coarse-grained commercial purity titanium is presented. In addition, the ballistic testing results of the Ti–6Al–4V alloy highlighted very different deformation twinning characteristics. Commercial purity titanium deformed plastically by a combination of {101‾2} and {112‾1} tensilve twinning and {112‾4} and {112‾2} compression twinning modes. By contrast, the deformation twinning of Ti–6Al–4V was limited to only the {101‾2} and {112‾1} tensile twinning modes. The two tensile deformation twinning types have very different morphologies in equiaxed fine grained Ti–6Al–4V. {112‾1} deformation twins span multiple grain boundaries and {101‾2} deformation twins reorient entire grains to a twinned orientation. This observation provides evidence for whole grain twinning of equiaxed fine grained Ti–6Al–4V by {101‾2} twinning. Grain boundary interactions between various deformation twinning types and alpha phase grain boundaries in commercial purity titanium and Ti–6Al–4V are reported and analysed. In commercial purity titanium {101‾2} as well as other deformation twinning types were observed interacting across alpha phase boundaries and higher angle alpha phase grain boundaries. The analyses of the manufacturing processes of Ti–6Al–4V highlight the very different dislocation and deformation twinning structures in surfaces processed by these techniques. A notable feature of material processed by laser shock peening is the almost complete absence of deformation twinning, contrasting with the frequent observation of extensive deformation twinning observed in the material processed by metallic shot peening and deep cold rolling. Therefore, the findings suggest that there is a strain rate limit above which deformation twinning is suppressed. The implications of this research are that a better understanding of the conditions that that favour certain deformation twinning types or propagation behaviours will enable more accurate plasticity modelling and better alloy design. This is important for the design and the manufacturing of titanium components and the high strain rate deformation to which titanium components in aerospace gas turbines can be subjected because of bird strike, foreign object debris ingestion or fan blade failures.
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A methodology for ballistic missile defense systems analysis using nested neural networksWeaver, Brian Lee 10 July 2008 (has links)
The high costs and political tensions associated with Ballistic Missile Defense Systems (BMDS) has driven much of the testing and evaluation of BMDS to be performed through high fidelity Modeling and Simulation (M&S). In response, the M&S environments have become highly complex, extremely computationally intensive, and far too slow to be of use to systems engineers and high level decision makers.
Regression models can be used to map the system characteristics to the metrics of interest, bringing about large quantities of data and allowing for real-time interaction with high-fidelity M&S environments, however the abundance of discontinuities and non-unique solutions makes the application of regression techniques hazardous. Due to these ambiguities, the transfer function from the characteristics to the metrics appears to have multiple solutions for a given set of inputs, which combined with the multiple inputs yielding the same set of outputs, causes troubles in creating a mapping. Due to the abundance of discontinuities, the existence of a neural network mapping from the system attributes to the performance metrics is not guaranteed, and if the mapping does exist, it requires a large amount of data to be for creating a regression model, making regression techniques less suitable to BMDS analysis.
By employing Nested Neural Networks (NNNs), intermediate data can be associated with an ambiguous output which can allow for a regression model to be made. The addition of intermediate data incorporates more knowledge of the design space into the analysis. Nested neural networks divide the design space to form a piece-wise continuous function, which allows for the user to incorporate system knowledge into the surrogate modeling process while reducing the size of a data set required to form the regression model.
This thesis defines nested neural networks along with methods and techniques for using NNNs to relieve the effects of discontinuities and non-unique solutions. To show the benefit of the approach, these techniques are applies them to a BMDS simulation. Case studies are performed to optimize the system configurations and assess robustness which could not be done without the regression models.
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The development of United States anti-ballistic missile policy, 1961-1972Cameron, James Jerome John January 2014 (has links)
No description available.
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The Future of Telemetry as a Cooperative Measure in Arms ControlHavrilak, George T. 11 1900 (has links)
International Telemetering Conference Proceedings / October 30-November 02, 1995 / Riviera Hotel, Las Vegas, Nevada / This paper suggests possible applications of telemetry as a cooperative measure in potential, future arms control agreements related to missiles and space launch vehicles (i.e., an agreement leading to clarification of the ABM Treaty for theater missile defense, and a notional regional or global ban on ground-launched, theater-range missiles). The opportunities for telemetry as a cooperative measure in future international arms control agreements should certainly grow, as confidence and appreciation in its utility are realized from the on-going ballistic missile telemetry exchanges between the US and Russia in START implementation.
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Tunnelling and noise in GaAs and graphene nanostructuresMayorov, Alexander January 2008 (has links)
Experimental studies presented in this thesis have shown the first realisation of resonant tunnelling transport through two impurities in a vertical double-barrier tunnelling diode; have proved the chiral nature of charge carriers in graphene by studying ballistic transport through graphene $p$-$n$ junctions; have demonstrated significant differences of $1/f$ noise in graphene compared with conventional two-dimensional systems. Magnetic field parallel to the current has been used to investigate resonant tunnelling through a double impurity in a vertical double-barrier resonant tunnelling diode, by measuring the current-voltage and differential conductance-voltage characteristics of the structure. It is shown that such experiments allow one to obtain the energy levels, the effective electron mass and spatial positions of the impurities. The chiral nature of the carriers in graphene has been demonstrated by comparing measurements of the conductance of a graphene $p$-$n$-$p$ structure with the predictions of diffusive models. This allowed us to find, unambiguously, the contribution of ballistic resistance of graphene $p$-$n$ junctions to the total resistance of the $p$-$n$-$p$ structure. In order to do this, the band profile of the $p$-$n$-$p$ structure has been calculated using the realistic density of states in graphene. It has been shown that the developed models of diffusive transport can be applied to explain the main features of the magnetoresistance of $p$-$n$-$p$ structures. It was shown that $1/f$ noise in graphene has much more complicated concentration and temperature dependences near the Dirac point than in usual metallic systems, possibly due to the existence of the electron-hole puddles in the electro-neutrality region. In the regions of high carrier concentration where no inhomogeneity is expected, the noise has an inverse square root dependence on the concentration, which is also in contradiction with the Hooge relation.
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Fractional Brownian motion and dynamic approach to complexity.Cakir, Rasit 08 1900 (has links)
The dynamic approach to fractional Brownian motion (FBM) establishes a link between non-Poisson renewal process with abrupt jumps resetting to zero the system's memory and correlated dynamic processes, whose individual trajectories keep a non-vanishing memory of their past time evolution. It is well known that the recrossing times of the origin by an ordinary 1D diffusion trajectory generates a distribution of time distances between two consecutive origin recrossing times with an inverse power law with index m=1.5. However, with theoretical and numerical arguments, it is proved that this is the special case of a more general condition, insofar as the recrossing times produced by the dynamic FBM generates process with m=2-H. Later, the model of ballistic deposition is studied, which is as a simple way to establish cooperation among the columns of a growing surface, to show that cooperation generates memory properties and, at same time, non-Poisson renewal events. Finally, the connection between trajectory and density memory is discussed, showing that the trajectory memory does not necessarily yields density memory, and density memory might be compatible with the existence of abrupt jumps resetting to zero the system's memory.
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Command structure of the ballistic missile defense systemWeller, David B. 03 1900 (has links)
Approved for public release; distribution is unlimited. / The United States is embarking on a course of designing and fielding a Ballistic Missile Defense System (BMDS) to protect the US and her citizenry against ballistic missile attacks. The BMDS will need a Command and Control, Battle Management, and Communications (C2BMC) organization/system to support military and national decision makers in times of crisis. The C2BMC must also be able to react quickly once a missile event has occurred. This thesis will cover the doctrinal issues with merging Theater Missile Defense (TMD) and the National Missile Warning System into one system, how the Unified Command Plan affects missile defense efforts, the lessons learned from Desert Storm, and presents alternative chains of command that might allow the BMDS to engage threat missiles in a timely and efficient manner. Preliminary findings indicate that a 'flattened' chain of command for missile defense forces seems to be a positive starting point for the initial deployment of the BMDS. / Lieutenant Commander, United States Navy
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