Browsing Aeronautics and astronautics by Title
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Networked Dynamic Systems: Identification, Controllability, and Randomness
(20130723)The presented dissertation aims to develop a graphcentric framework for the analysis and synthesis of networked dynamic systems (NDS) consisting of multiple dynamic units that interact via an interconnection topology. ... 
NoiseEnabled Observability of Nonlinear Dynamic Systems Using the Empirical Observability Gramian
While control actuation is well understood to influence the observability of nonlinear dynamical systems, actuation of nonlinear stochastic systems by process noise has received comparatively little attention in terms of ... 
Nonlinear Aeroelastic Behavior of Tail / Rudder Systems with Freeplay and Actuator Failure
(20130725)This thesis discusses the development of numerical simulations implemented in MATLAB and of an experimental tail/rudder model for the investigation of the effects of nonlinearities on control surface flutter of a threedegree ... 
A Numerical Investigation of Rectangular Cylinders with Interest in Maximizing Drag
In this dissertation, rectangular cylinder flow is explored through a series of numerical simulations. First, rectangular cylinders at a Reynolds number of 20,000 are simulated using ReynoldsAveraged NavierStokes (RANS) ... 
Numerical Methods for 3dimensional Magnetic Confinement Configurations using TwoFluid Plasma Equations
(UMI, 20100624)The 5moment twofluid plasma model uses Euler equations to describe the ion and electron fluids, and Maxwell's equations to describe the electric and magnetic fields. Twofluid physics becomes significant when the ... 
Numerical simulation of unsteady hypersonic chemically reacting flow
(1995)The goal of this research is to develop and evaluate a new algorithm for the numerical solution of the axisymmetric NavierStokes equations for unsteady hypersonic flow with chemically reacting gas species. The LUSGS ... 
Numerically Generated Tangent Stiffness Matrices for Geometrically NonLinear Structures
(20130725)The aim of this thesis is to develop a general numerical solution method for geometrically nonlinear structures. Most common work involves tedious derivations of analytic tangent stiffness matrices. The major objective ... 
Observability Based Path Planning in Rangeonly Localization
(20131114)The motivations of oceanographic research have driven the development of autonomous underwater vehicles (AUVs) now capable of great feats of autonomy and endurance. It is anticipated that the future of autonomous oceanographic ... 
ObservabilityBased Approach to Design, Analysis and Optimization of Dynamical Systems
The present dissertation aims to use the coupling between actuation and sensing in nonlinear systems to alternatively design a set of feasible control policies, to find the minimum number of sensors, or to find an optimal ... 
ObservabilityBased Guidance and Sensor Placement
Control system performance is highly dependent on the quality of sensor information available. In a growing number of applications, however, the control task must be accomplished with limited sensing capabilities. This ... 
On the Mach number Effects on Droplet Breakup in Laminar Flow
A Volume of Fluid (VOF) multiphase numerical study was conducted using the commercial simulation software ANSYS Fluent to understand the effects of compressibility on droplet breakup in the laminar flow regime. A 2D ... 
On the Quasi OneDimensional Structure of TwoDimensional Cellular Detonations in a Duct
Adaptive mesh refinement combined with a WENOTCD hybrid numerical method are used to simulate cellular detonations in ducts using a detailed chemical mechanism linked to the inviscid Euler equations. Using this computational ... 
Operation of Polycarbonate Projectiles in the Ram Accelerator
(20131114)The ram accelerator is a hypervelocity launcher with direct space launch applications in which a subcaliber projectile, analogous to the centerbody of a ramjet engine, flies through fuel and oxidizer that have been ... 
Parallel Adaptive Simulation of Detonation Waves Using a Weighted Essentially NonOscillatory Scheme
The purpose of this thesis was to develop a code that could be used to develop a better understanding of the physics of detonation waves. First, a detonation was simulated in one dimension using ZND theory. Then, using the ... 
Paramagnetic spinup of a field reversed configuration with rotating magnetic field current drive
(2003)A transverse Rotating Magnetic Field (RMF) can drive toroidal current and sustain the poloidal flux of a Field Reversed Configuration (FRC) through the application of a 〈vz x Br〉 Lorentz force on the electrons, where vz ... 
A Parametric Analysis of the Aerodynamic Characteristics of Volleyballs in Turbulent Flow
(20120810)A wind tunnel experiment was conducted to compare the flight path characteristics and drag of current models of volleyballs. An open circuit low speed wind tunnel was primarily used to gather lift and drag data on multiple ... 
PID Control Simulation and Kalman Filter State Estimation of HITSIInjector Flux Circuit
In order to implement an optimal modern control system on the HITSI injector voltage and flux circuits, it is first necessary to apply state estimation techniques, allowing the physical system to be observed by the ... 
Probabilistic Estimation of State via Propagation of Error for a Collision Warning System
The Federal Aviation Administration (FAA) is scheduled to open the national airspace to Unmanned Aerial Systems (UAS) by 2015. Although there are many beneficial applications by integrating UASs into the national airspace, ... 
SemiAutonomous Networks: Effective Control of Networked Systems through Protocols, Design, and Modeling
(20131114)The objective of this dissertation is to explore the analysis and design of controlled networked dynamic systems  dubbed semiautonomous networks. This work approaches the problem of effective control of semiautonomous ...