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Computer Vision For Autonomous Driving
No full textAutonomous vehicles rely on computer vision to perceive their environment and operate safely within it, but the effects of weather and lighting such as rain, fog, and night can significantly impact the performance of vision systems. For reliable integration into traffic, autonomous vehicles’ computer vision must be robust to the varying effects of weather. We measured the effects of weather on semantic segmentation and tracking models with simulated data, and then implemented three approaches to mitigate the effects of weather: domain adaptation with fine tuning, de-weathering model input, and multimodal sensor fusion. We collected image and lidar data on city driving scenes in the CARLA simulator across four scenarios: clear day, foggy day, rainy day, and clear night. After obtaining baseline performance for models trained on each of these scenarios, we evaluated our mitigation strategies. We show improvements in cross-domain performance for each of these methods and compare the merits and demerits of each approach
Jenny and the Alien
No full textJenny, a grieving and anxious old woman, takes in a strange alien with a knack for radio
Hawking Radiation
No full textBlack holes present an excellent playing field for studying the intersection between general relativity and quantum mechanics. Understanding how these successful theories come together is a pivotal step towards formulating a Theory of Everything. As a result of performing quantum field theory in the curved spacetime around a black hole, we find Hawking Radiation - the one thing that manages to escape a black hole. Through a study of general relativity, thermodynamics, and quantum mechanics, we examine why Hawking Radiation must exist, the mechanisms behind it, and its consequences, including black hole explosions
From Point A to Point Human: The Journey of H5N1 Towards Sustained Human-to-Human Transmission
No full textH5N1 is a strain of Avian Influenza that is rapidly developing mutations that are allowing the virus to become better adapted to humans. These mutations are allowing H5N1 to bind to lung epithelial cells in humans, replicate in mammalian temperatures, and spread via airborne transmission. There are multiple explanations as to why these mutations are occurring at this unprecedented rate however, I argue that climate change and agricultural practices are the main factors allowing for these developments. These two factors are allowing H5N1 to have a broader host range, or infect more hosts, and through these new hosts, these mutated strains are finding new inhabitable environments
Provenance of the Kootznahoo Formation using U-Pb detrital zircon geochronology in southeastern Alaska
No full textThe Kootznahoo Formation in southeastern Alaska is a predominantly nonmarine clastic unit deposited on the Alexander terrane and the Gravina belt. Many of the outboard units along the coast of Alaska have migrated from further south along the North American coast including the Chugach-Prince William terrane. Unlike these outboard terranes the Kootznahoo Formation has not been deeply buried or metamorphosed making it an important unit for studies of provenance and the exhumation history of nearby terranes. Furthermore, many questions remain about the tectonic history of southeast Alaska. In order to build on the understanding of tectonic reconstructions in southeast Alaska, this study adds to detrital zircon U/Pb data for the Kootznahoo Formation to determine the location of the Chugach-Prince William terrane during deposition from the Paleocene to Miocene. Data collected in this study confirm that the provenance of the Kootznahoo Formation is primarily from the Coast Mountains batholith and the Admiralty Island volcanics. Furthermore, this study finds a strong similarity between the Kootznahoo Formation, the Orca Group, and the Sitka Greywacke from the Chugach-Prince William terrane suggesting these units share a sediment source and were nearby during deposition
Microstructural analysis and kinematic determinations of deformation bands from Parkfield, California: Implications for stress along the San Andreas fault
No full textMost studies document deformation bands in extensional or compressional tectonic regimes. In these settings, deformation bands typically have predictable kinematics that can be confirmed with slip surfaces and piercing points. This paper describes three well-developed sets of deformation bands from the Etchegoin Formation in Parkfield, California, less than one kilometer from the San Andreas fault. In this strike-slip tectonic regime, deformation bands have ambiguous kinematics and pre-folding geometries that further complicate kinematic determinations. Here, I use microstructural datasets to describe these bands and supplement field observations. I interpret in situ and unfolded maximum compressive horizontal stress (SHmax) directions from force chain directions and resolve these directions relative to band orientations to consider kinematics. This analysis indicates that Parkfield deformation bands consist of an early set of shear-enhanced compaction bands and two later sets of strike-slip compaction shear bands with left- and right-lateral displacements. Bands in the early set are likely synsedimentary structures related to Etchegoin lithification. Bands in the later two sets likely formed syn-folding with the Parkfield syncline and are related to deformation in the San Andreas fault zone. The median SHmax direction extracted from the later two sets of bands trends towards 012°, at an angle of 48° to the strike of the San Andreas in central California. This result has implications for stress along the plate boundary and may challenge the weak-fault hypothesis