Point Cloud Framework for Rendering 3D Models Using Google Tango

This project seeks to demonstrate the feasibility of point cloud meshing for capturing and modeling three dimensional objects on consumer smart phones and tablets. Traditional methods of capturing objects require hundreds of images, are very slow and consume a large amount of cellular data for the average consumer. Software developers need a starting point for capturing and meshing point clouds to create 3D models as hardware manufacturers provide the tools to capture point cloud data. The project uses Googles Tango computer vision library for Android to capture point clouds on devices with depth-sensing hardware. The point clouds are combined and meshed as models for use in 3D rendering projects. We expect our results to be embraced by the Android market because capturing point clouds is fast and does not carry a large data footprint

Lagrangian formalism of gravity in the Randall-Sundrum model

We derive the effective Lagrangian of the physical four-dimensional fields in the Randall-Sundrum (RS) model, and use this to calculate the Newtonian gravitational potential between two point sources on the brane. The effect of the radion is emphasized, and it is shown to disappear when the hidden brane is taken to infinity, i.e. when we only have one brane. As a preliminary, we derive the corresponding Lagrangian in the simpler geometry of a flat spacetime with one extra dimension compactified on a torus. We also study the gauge invariance of the theory, and note that the massless vector field that is present for the torus disappears in the RS model because of the orbifold symmetry.Comment: 10 pages, latex with revtex4, 5 postscript figures; Section on gauge transformations added, conclusions unchange

SAR Image Formation via Subapertures and 2D Backprojection

Radar imaging requires the use of wide bandwidth and a long coherent processing interval, resulting in range and Doppler migration throughout the observation period. This migration must be compensated in order to properly image a scene of interest at full resolution and there are many available algorithms having various strengths and weaknesses. Here, a subaperture-based imaging algorithm is proposed, which first forms range-Doppler (RD) images from slow-time sub-intervals, and then coherently integrates over the resulting coarse-resolution RD maps to produce a full resolution SAR image. A two-dimensional backprojection-style approach is used to perform distortion-free integration of these RD maps. This technique benefits from many of the same benefits as traditional backprojection; however, the architecture of the algorithm is chosen such that several steps are shared with typical target detection algorithms. These steps are chosen such that no compromises need to be made to data quality, allowing for high quality imaging while also preserving data for implementation of detection algorithms. Additionally, the algorithm benefits from computational savings that make it an excellent imaging algorithm for implementation in a simultaneous SAR-GMTI architecture

The Relative Industry Specific Effects of COVID-19 on Market Volatility and Liquidity

Understanding how historical events affect market volatility and liquidity can provide crucial information to financial analysts, investment professionals, and managers in the event that similar circumstances resurface. In this study, I look at how a global pandemic (COVID-19) can introduce frictions into the market and cause disrupt the generation or flow of available information, this could cause prices to deviate significantly from their equilibrium values. I also hypothesize that these inefficiencies may have a greater effect on some industries than others. My analysis seems to confirm this hypothesis. I observe that the global COVID-19 pandemic leads to statistically significant increases in the volatility of industries such as Meals, Games, and Mines relative to the market. I also find that the pandemic leads to significant liquidity deterioration relative to the market in industries including ElcEq, Carry, and Other

Higher order corrections to the Newtonian potential in the Randall-Sundrum model

The general formalism for calculating the Newtonian potential in fine-tuned or critical Randall-Sundrum braneworlds is outlined. It is based on using the full tensor structure of the graviton propagator. This approach avoids the brane-bending effect arising from calculating the potential for a point source. For a single brane, this gives a clear understanding of the disputed overall factor 4/3 entering the correction. The result can be written on a compact form which is evaluated to high accuracy for both short and large distances.Comment: 12 pages, LaTeX2e with RevTeX4, 3 postscript figures; Minor corrections, references update

Bombus impatiens (Hymenoptera: Apidae) display reduced pollen foraging behavior when marked with bee tags vs. paint

Numbered bee tags, developed for marking honey bees (Apis mellifera Linnaeus), are glued to the mesosoma of many bees to uniquely identify them.  We recorded whether or not bees sonicated to collect pollen after being marked, and we compared the sonication frequency, sonication length, and wing beat frequency of Bombus (Pyrobombus) impatiens Cresson that were tagged with bee tags vs. marked with paint.  We found that bees with tags glued to their mesosoma had no significant change in wing beat frequency, sonication frequency, or sonication length, relative to bees that were marked with paint; however, we found that the probability of collecting pollen via sonication after being marked was much lower for bees marked with bee tags vs. paint