Browsing Aeronautics and astronautics by Title
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Learning in Complex Dynamic Systems : with Applications to Perpetual Flight, Energy Management, Distributed Decision Making, and Social Networks
This dissertation addresses learning in complex dynamic systems with applications to perpetual flight, energy management, collaborative decision making, and social networks. By increasing the size and complexity of network ... 
LowSpeed Stability and Control of Exploratory Tailless LongRange Supersonic Configurations
This thesis presents studies of the lowspeed stability and control of a representative longrange supersonic flight vehicle. The aircraft of interest is a research uninhabited aerial vehicle (RUAV), a 1/16th scaled model ... 
MHD Modeling in Complex 3D Geometries: Towards Predictive Simulation of SIHI Current Drive
(20140430)The HITSI experiment studies Steady Inductive Helicity Injection (SIHI) for the purpose of forming and sustaining a spheromak plasma. A spheromak is formed in a nearly axisymmetric flux conserver, with a bow tie cross ... 
Modeling Aircraft Position and Conservatively Calculating Airspace Violations for an Autonomous Collision Awareness System for Unmanned Aerial Systems
With the scheduled 30 September 2015 integration of Unmanned Aerial System (UAS) into the national airspace, the Federal Aviation Administration (FAA) is concerned with UAS capabilities to sense and avoid conflicts. Since ... 
Modeling and Control of a Quadrotor with Dynamic Inertia
(20130723)As the support and technology for unmanned vehicles has increased, so have the possible applications for Unmanned Aerial Vehicles (UAVs). From military intelligence gathering missions, to civilian search and rescue missions, ... 
Modeling collisional processes in plasmas using discontinuous numerical methods
Fluidbased plasma models are typically applied to parameter regimes where a local thermal equilibrium is assumed. The applicability of this regime is valid for many plasmas, however, it is limited to plasma dynamics ... 
MultiVehicle Function Tracking by Moment Matching
The evolution of many natural and manmade environmental events can be represented as scalar functions of time and space. Examples include the boundary and intensity of wildfires, of waste spills in bodies of water, and ... 
Multifunctional Thin Film Lithium Ion  Graphite Composite Structural Laminates
(20140224)The consolidation of batteries and airframe into a multifunctional structure can theoretically reduce the aircraft weight by exploiting the battery components as load bearing elements and by enabling a distributed power ... 
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 ...