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Development Of A High Performance Parallel Computing Platform And Its Use In The Study Of Nanostructures : Clusters, Sheets And Tubes ., S. Gowtham

Dissertations, Master's Theses and Master's Reports - Open

Small clusters of gallium oxide, technologically important high temperature ceramic, together with interaction of nucleic acid bases with graphene and small-diameter carbon nanotube are focus of first principles calculations in this work. A high performance parallel computing platform is also developed to perform these calculations at Michigan Tech. First principles calculations are based on density functional theory employing either local density or gradient-corrected approximation together with plane wave and gaussian basis sets.

The bulk Ga₂O₃ is known to be a very good candidate for fabricating electronic devices that operate at high temperatures. To explore the properties of …

In-Situ Measurement And Characterization Of Cloud Particles Using Digital In-Line Holography, Jacob P. Fugal

Dissertations, Master's Theses and Master's Reports - Open

Satellite measurement validations, climate models, atmospheric radiative transfer models and cloud models, all depend on accurate measurements of cloud particle size distributions, number densities, spatial distributions, and other parameters relevant to cloud microphysical processes. And many airborne instruments designed to measure size distributions and concentrations of cloud particles have large uncertainties in measuring number densities and size distributions of small ice crystals. HOLODEC (Holographic Detector for Clouds) is a new instrument that does not have many of these uncertainties and makes possible measurements that other probes have never made. The advantages of HOLODEC are inherent to the holographic method.

In …

First-Principles Studies Of Boron Nanostructures, Kah Chun Lau

Dissertations, Master's Theses and Master's Reports - Open

Boron is an 'electron deficient' element which has a rather fascinating chemical versatility. In the solid state, the elemental boron has neither a pure covalent nor a pure metallic character. As a result, its vast structural dimensionally and peculiar bonding features hold a unique place among other elements in the periodic table. In order to understand and properly describe these unusual bonding features, a detailed and systematic theoretical study is needed. In this work, I will show that some of the qualitative features of boron nanostructures, including clusters, sheets and nanotubes can easily be extracted from the results of first …

Pupil Phase Apodization For Achromatic Imaging Of Extra-Solar Planets, Weidong Yang

Dissertations, Master's Theses and Master's Reports - Open

Direct imaging of extra-solar planets in the visible and infrared region has generated great interest among scientists and the general public as well. However, this is a challenging problem. Diffculties of detecting a planet (faint source) are caused, mostly, by two factors: sidelobes caused by starlight diffraction from the edge of the pupil and the randomly scattered starlight caused by the phase errors from the imperfections in the optical system. While the latter diffculty can be corrected by high density active deformable mirrors with advanced phase sensing and control technology, the optimized strategy for suppressing the diffraction sidelobes is still …