Mechanical characterization of individual polycrystalline carbon tubes for use in electrical nano-interconnects

Polycrystalline carbon tubes were generated by CVD inside electrochemically prepared nano-porous anodic aluminium oxide membranes. This method produced nano-tubes without catalyst, featuring polycrystalline and a few layer thick walls. Individual tubes could be isolated and suspended on microfabricated substrates such that they formed single-side clamped beams. These beams were then used to investigate their mechanical properties employing electrostatic forces for bending the tubes beyond their mechanical stability where pull-in occurs, which could be detected by monitoring the current flowing from the tube to the substrate

Behavorial Lateralization of Pectoral Fin Rubbing Researched In 27 Identified Bottlenose Dolphins

This thesis takes a look at the behavioral lateralization of handedness present or not present within the bottlenose dolphin (Tursiops truncatus) population housed at the Roatan Institute for Marine Sciences. Dolphins and humans share similar brain structures in that the brain is split into hemispheres that allow an individual to present behaviorally dominate features on different sides of their body. This type of split brain structure allows for a phenomenon known as handedness, where one hand presents dominant motor control. For dolphins, their “hand” is their pectoral fin. This thesis looked at a managed care population to investigate the possibility of a dominant pectoral fin when engaging in contact behaviors or carrying objects. The statistics seemed to show a more even distribution of ambidextrousness than dominance, which still offers insight into their unconscious behaviors

DNS of vertical plane channel flow with finite-size particles: Voronoi analysis, acceleration statistics and particle-conditioned averaging

We have performed a direct numerical simulation of dilute turbulent particulate flow in a vertical plane channel, fully resolving the phase interfaces. The flow conditions are the same as those in the main case of "Uhlmann, M., Phys. Fluids, vol. 20, 2008, 053305", with the exception of the computational domain length which has been doubled in the present study. The statistics of flow and particle motion are not significantly altered by the elongation of the domain. The large-scale columnar-like structures which had previously been identified do persist and they are still only marginally decorrelated in the prolonged domain. Voronoi analysis of the spatial particle distribution shows that the state of the dispersed phase can be characterized as slightly more ordered than random tending towards a homogeneous spatial distribution. It is also found that the p.d.f.'s of Lagrangian particle accelerations for wall-normal and spanwise directions follow a lognormal distribution as observed in previous experiments of homogeneous flows. The streamwise component deviates from this law presenting significant skewness. Finally, a statistical analysis of the flow in the near field around the particles reveals that particle wakes present two regions, a near wake where the velocity deficit decays as 1/x and a far wake with a decay of approximately 1/(x*x).Comment: accepted for publication in Int. J. Multiphase Flo

Development of a toolchain for the conceptual design of fixed-wing VTOL UAVs

This report presents the techniques and methods used to set up a toolchain for the automation of the conceptual design phase for a small, fixed-wing UAV with VTOL capabilities. The conceptual design is a phase in the design process of a UAV that heavily influences both the preliminary and detailed design that follows. The main challenge for the development of a conceptual design for a small, VTOL-capable UAV is the number of circular dependencies between the different components of the aircraft. A literature review is conducted to find existing methods to determine the required size and weight of the systems. A conceptual design toolchain using the Python programming language has been developed to determine the size and weight of the systems for a set of requirements, in the form of a toolchain in Python. Lastly, a verification process is conducted to ensure that the methods employed result in a realistically sized UAV