A majority of the efforts in modeling crack propagation have used continuum models built upon partial derivatives with respect to the spatial coordinates in the force and displacement relationship. These methods are ...

First part of this thesis (chapters 1-5) studies the effect of small noise perturbations on delay differential equations (DDE) whose fixed point is on the verge of instability. With appropriate scaling of coordinates, the ...

The study of vehicles traveling at hypersonic speeds is extremely complex and involves many different non-equilibrium physical phenomena occurring on many different time-scales. As a result, work focused on modeling this ...

In recent flight tests the X-38 reentry test vehicle spins during the deployment of the drogue parachute. An experimental aerodynamic study has been conducted at the University of Illinois using a scale model of the X-38 ...

The mean and gradient residual stresses and the failure behavior of individual layers in inorganic thin film photovoltaics were investigated. The thin film photovoltaics consisted of an amorphous silicon (Si) p-n junction ...

Flapping flight micro aerial vehicles (MAVs) are of interest to the aerospace and robotics communities for their maneuverability in comparison to tradition fixed wing and rotary aircraft. However they present numerous ...

The development of a new spacecraft trajectory design method most often occurs because a particular capability does not exist. The invention is usually considered successful so long as it is capable of producing solutions ...

Polymeric nanostructures are quite distinct because of the large ratio of surface-to-volume macromolecules which result in very different physical and mechanical behavior compared to bulk. Of special interest are nanostructures ...

The effect of random air turbulence on the coupled flap-lag motion of a helicopter rotor blade in forward flight is investigated. By assuming white noise turbulence and applying a special case of the stochastic averaging ...