LiDAR Segmentation-based Adversarial Attacks on Autonomous Vehicles

Autonomous vehicles utilizing LiDAR-based 3D perception systems are susceptible to adversarial attacks. This paper focuses on a specific attack scenario that relies on the creation of adversarial point clusters with the intention of fooling the segmentation model utilized by LiDAR into misclassifying point cloud data. This can be translated into the real world with the placement of objects (such as road signs or cardboard) at these adversarial point cluster locations. These locations are generated through an optimization algorithm performed on said adversarial point clusters that are introduced by the attacker

Mars' Energetic Plume Ion Escape Channel

Mars is losing its atmosphere. The planet’s small size results in relatively low energy requirements for atmospheric particles to escape into deep space, and its lack of a planetary magnetic field allows the solar wind to directly interact with the upper atmosphere, providing an additional source from which particles may obtain this requisite energy. The escape of particles from Mar’s atmosphere over the course of billions of years is not only a story of atmospheric evolution; it is a story of the evolution of a global climate. It is now thought that oceans worth of liquid water may have existed on a warmer ancient Mars, and atmospheric escape of hydrogen and oxygen is one explanation of how such an ocean may have vanished. The research presented here revolves around the examination of one particular "loss channel" for oxygen (and other "heavy" ions) from Mars. This loss channel, known as the "energetic plume," consists of pickup ions, electrically charged planetary particles that, finding themselves in the solar wind flow past Mars, are accelerated in the direction of the solar wind's convective electric field (ESW). In the spatially zoomed out view, the acceleration in this direction is just the initial part of the first gyration of an ESW-cross-B drift in the direction of solar wind flow. Zoomed in closer to Mars, where ion-observing satellites have orbited, a result of the huge gyroradius of these pickup ions is that, in addition to having high energies, energetic plume particles have flight directions distinct from other escaping particles and are observed at locations not reached by other escaping particles. This dissertation introduces the Mars space environment and the problem of atmospheric escape generally before presenting the search for this distinct phase space signature of the energetic plume in ion data from the Mars Express satellite. It was found that despite the presence of obstacles to observing the energetic plume using the Ion Mass Analyzer (IMA) onboard Mars Express, it is possible to both identify unambiguous instances of energetic plume observations in IMA data and to see signatures of the energetic plume in statistical maps of the Mars space environment made using IMA observations. Furthermore, it was found that accounting for “weathervaning” – the subsolarward bending of magnetic field lines draped around the ionosphere – can be used to improve estimates of the direction of ESW. The resulting more accurate estimate for the direction of ESW improves statistical representations of the energetic plume in IMA data, and significant quantities of energetic plume type ions are observed by IMA ~ 60% more frequently in the newly estimated direction of ESW than in the previously estimated direction of ESW. We conclude that the improved method of estimating the direction of ESW should be used in place of previously existing proxies in studies concerning the variation of energetic plume fluxes for different solar conditions during the time period between Jan. 2004 and Oct. 2006.PHDAtmospheric, Oceanic & Space ScienceUniversity of Michigan, Horace H. Rackham School of Graduate Studieshttps://deepblue.lib.umich.edu/bitstream/2027.42/143899/1/blakecjo_1.pd

Culminating Project Report- Warren J. Baker Center for Science and Mathematics

This report analyzes the fire protection features of the Warren J. Baker Center for Science and Mathematics on the Cal Poly San Luis Obispo campus in San Luis Obispo, CA. The prescriptive analysis of the structural fire protection, egress, fire suppression, and fire alarm, detection, and communication systems shows that the building meets the requirements of current codes and standards. The performance based analysis includes simulating design fire scenarios in the atrium using computer modeling (CFAST, FDS) and the results of these models show that the atrium meets the tenability criterion for the calculated evacuation time of occupants

Four Trinity Sunday Cantatas by J. S. Bach: An Examination and Comparison

While the four cantatas presented on Trinity Sunday during Bach\u27s Leipzig years -- BWV 194, 176, 165, and 129 -- were all intended for the same liturgical day, a significant diversity exists among the four compositions. This diversity results from the variety of source material on which the cantatas were based, including material composed during the Leipzig years as well as material re-worked from previous Bach cantatas. The diversity also results from the different librettos and librettists that were utilized for the cantatas. Other factors include the variety of the cantatas\u27 movement structures, performing forces, and the theological/philosophical themes that are central to each composition. This document is a study of the four cantatas, first examining the compositions in detail, then examining the compositions by their commonalities and their dissimilarities, with specific attention to the methods by which Bach presented the theological/philosophical messages in each cantata. An appendix of translations and scriptural allusions for each cantata movement is also included at the close of the document. The variety of perspectives employed in this document forms a unique examination of the four Trinity Sunday cantatas that has not previously been seen in Bach scholarship

Biomechanical Evaluation of a Jackhammering Task with and Without List Assist

The construction and utility industries have relatively high levels of hazardous tasks that impose high physical demands on a worker. For the past decade these industry sectors had one of highest incident rates for non-fatal injuries (BLS, 2013). The task of operating a jackhammer presents several risk factors that promote the high rates of injuries to this industry sector. Until the introduction of the lift assist, relatively few interventions were available to make the task of operating a jackhammer safer. However, no research has been conducted to support that this device is able to make jackhammering safer. The aim of this study was to evaluate and quantify the changes of operating a jackhammer with and without a lift assist. Eight experienced jackhammer operators participated in this study. All participants were asked to use a 90lb and 60lb jackhammer once with the lift assist attachment and once without the lift assist attachment while breaking a 3\u27x3\u27 concrete section. Throughout the trials, grip pressure, bilateral muscle activity, vibration, and task time were recorded. For each variable a general linear model ANOVA was with 95% confidence was performed to determine statistically significance changes. The factors of lift assist, weight, and the interaction between the two were factors in the ANOVA. The factor of subject was blocked. Results showed that using the lift assist reduced the grip pressure and muscle activity for the lifting portion of the task. During operation, using the lift assist did not result in a change of vibration amplitude on the jackhammer or dose of the exposure to the operator or affect the grip pressure needed to operate the jackhammer. However, the task time was slightly increased. This is suspected to be due to the inexperience of the operators with using the lift assist. These results support that the lift assist reduces the lifting effort/demands required of the operator, while without altering other risk factors during the jackhammering task. Reduction in the jackhammer lifting effort while using a lift assist device may lead to a reduced risk of overexertion injuries, as well as allow more diverse population of the operators to perform the task

Processing of Binaural Information in Human Auditory Cortex

24 page(s

Trial by Fire: Cultural Complacency, Institutional Learning, and the Development of the Fire Warden System in Minnesota, 1870-1920

Between 1870 and 1920 Minnesota business culture focused on depleting the land of its resources with little regulation while the ecological landscape was influenced by a hot and dry climatic cycle. As these two forces collide, Minnesota experiences its four “great fires” (1894, 1908, 1910, and 1918). Each of these fires provide substantive documentation on emergency response and relief illustrating Minnesota’s development of a disaster response program. With several localized fires, the learning gained from fire to fire can be assessed. After evaluating the responses to each of these fires, one can conclude that although technological advancements and complex relief organizations developed between fires, the business culture of Minnesota stymied any real learning on behalf of Minnesota settlers. The stymied learning of the settlers led to a similar death count for the first and fourth fires