5,613 research outputs found

    Present at Creation: The Founding of the Society of Georgia Archivists

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    As we envisioned this session, our panel would discuss what brought them together, why they felt the ·need to organize; what they envisioned for SGA as a professional organization; how did they view its development; how they have viewed its development over the last few years; and what they would like to see for its future. Then, we thought that following some discussion about our beginning, it would be a very valuable exercise for those of us here to have a forum to explore development for SGA and what we, as a group, would like to have come from our organization

    Qualifying System F-sub

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    Type qualifiers offer a lightweight mechanism for enriching existing type systems to enforce additional, desirable, program invariants. They do so by offering a restricted but effective form of subtyping. While the theory of type qualifiers is well understood and present in many programming languages today, polymorphism over type qualifiers is an area that is less examined. We explore how such a polymorphic system could arise by constructing a calculus System F<:Q which combines the higher-rank bounded polymorphism of System F<: with the theory of type qualifiers. We explore how the ideas used to construct System F<:Q can be reused in situations where type qualifiers naturally arise -- in reference immutability, function colouring, and capture checking. Finally, we re-examine other qualifier systems in the literature in light of the observations presented while developing System F<:Q.Comment: 24 page

    Trick or Heat? Manipulating Critical Temperature-Based Control Systems Using Rectification Attacks

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    Temperature sensing and control systems are widely used in the closed-loop control of critical processes such as maintaining the thermal stability of patients, or in alarm systems for detecting temperature-related hazards. However, the security of these systems has yet to be completely explored, leaving potential attack surfaces that can be exploited to take control over critical systems. In this paper we investigate the reliability of temperature-based control systems from a security and safety perspective. We show how unexpected consequences and safety risks can be induced by physical-level attacks on analog temperature sensing components. For instance, we demonstrate that an adversary could remotely manipulate the temperature sensor measurements of an infant incubator to cause potential safety issues, without tampering with the victim system or triggering automatic temperature alarms. This attack exploits the unintended rectification effect that can be induced in operational and instrumentation amplifiers to control the sensor output, tricking the internal control loop of the victim system to heat up or cool down. Furthermore, we show how the exploit of this hardware-level vulnerability could affect different classes of analog sensors that share similar signal conditioning processes. Our experimental results indicate that conventional defenses commonly deployed in these systems are not sufficient to mitigate the threat, so we propose a prototype design of a low-cost anomaly detector for critical applications to ensure the integrity of temperature sensor signals.Comment: Accepted at the ACM Conference on Computer and Communications Security (CCS), 201

    VisAlign: Dataset for Measuring the Degree of Alignment between AI and Humans in Visual Perception

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    AI alignment refers to models acting towards human-intended goals, preferences, or ethical principles. Given that most large-scale deep learning models act as black boxes and cannot be manually controlled, analyzing the similarity between models and humans can be a proxy measure for ensuring AI safety. In this paper, we focus on the models' visual perception alignment with humans, further referred to as AI-human visual alignment. Specifically, we propose a new dataset for measuring AI-human visual alignment in terms of image classification, a fundamental task in machine perception. In order to evaluate AI-human visual alignment, a dataset should encompass samples with various scenarios that may arise in the real world and have gold human perception labels. Our dataset consists of three groups of samples, namely Must-Act (i.e., Must-Classify), Must-Abstain, and Uncertain, based on the quantity and clarity of visual information in an image and further divided into eight categories. All samples have a gold human perception label; even Uncertain (severely blurry) sample labels were obtained via crowd-sourcing. The validity of our dataset is verified by sampling theory, statistical theories related to survey design, and experts in the related fields. Using our dataset, we analyze the visual alignment and reliability of five popular visual perception models and seven abstention methods. Our code and data is available at \url{https://github.com/jiyounglee-0523/VisAlign}

    Baja SAE eCVT Mechanical Design

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    This objective of this project was to design, manufacture, and test the mechanical systems of an electronically-controlled continuously variable transmission (eCVT) for the Cal Poly Baja SAE vehicle

    HTT is a repressor of ABL activity required for APP induced axonal growth

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    ABL tyrosine kinase activity controls several aspects of development including axon patterning. Amyloid precursor protein (APP) is linked to Alzheimer's disease and previous work established that ABL is a downstream effector in an Appl, the Drosophila App ortholog, signaling pathway which modulates axon outgrowth in the mushroom bodies (MBs), the fly memory center. Here we show that Abl is required for the MB neuron axonal growth. Importantly, both Abl overexpression and lack of expression produce a similar phenotype in the MBs indicating the necessity of tightly regulating ABL activity. We find that the fly huntingtin protein (HTT), the homolog of the protein involved in Huntington's disease, behaves genetically as a repressor of ABL activity. Supporting this, FRET-based measurements of in vivo ABL activity in the MBs reveal a clear increase in its activity when HTT levels are reduced. Thus, in addition to its many other reported roles, HTT acts as a negative regulator of ABL activity, at least in the MBs, to maintain its appropriate physiological levels necessary for axon growth.

    Preliminary Testing of a Pressurized Space Suit and Candidate Fabrics Under Simulated Mars Dust Storm and Dust Devil Conditions

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    In August 2009 YAP Films (Toronto) received permission from all entities involved to create a documentary film illustrating what it might be like to be on the surface of Mars in a space suit during a dust storm or in a dust devil. The science consultants on this project utilized this opportunity to collect data which could be helpful to assess the durability of current space suit construction to the Martian environment. The NDX?1 prototype planetary space suit developed at the University of North Dakota was used in this study. The suit features a hard upper torso garment, and a soft lower torso and boots assembly. On top of that, a nylon-cotton outer layer is used to protect the suit from dust. Unmanned tests were carried out in the Martian Surface Wind Tunnel (MARSWIT) at the NASA Ames Research Center, with the suit pressurized to 10 kPa gauge. These tests blasted the space suit upper torso and helmet, and a collection of nine candidate outer layer fabrics, with wind-borne simulant for five different 10 minute tests under both terrestrial and Martian surface pressures. The infiltration of the dust through the outer fabric of the space suit was photographically documented. The nine fabric samples were analyzed under light and electron microscopes for abrasion damage. Manned tests were carried out at Showbiz Studios (Van Nuys, CA) with the pressure maintained at 20?2 kPa gauge. A large fan-created vortex lifted Martian dust simulant (Fullers Earth or JSC Mars?1) off of the floor, and one of the authors (Lee) wearing the NDX?1 space suit walked through it to judge both subjectively and objectively how the suit performed under these conditions. Both the procedures to scale the tests to Martian conditions and the results of the infiltration and abrasion studies will be discussed

    Trex1 regulates lysosomal biogenesis and interferon-independent activation of antiviral genes

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    Innate immune sensing of viral nucleic acids triggers type I interferon (IFN) production, which activates interferon-stimulated genes (ISGs) and directs a multifaceted antiviral response. ISGs can also be activated through IFN-independent pathways, although the precise mechanisms remain elusive. Here we found that the cytosolic exonuclease Trex1 regulates the activation of a subset of ISGs independently of IFN. Both Trex1−/− mouse and TREX1-mutant human cells express high levels of antiviral genes and are refractory to viral infections. The IFN-independent activation of antiviral genes in Trex1−/− cells requires STING, TBK1 and IRF3 and IRF7. We also found that Trex1-deficient cells display expanded lysosomal compartment, altered subcellular localization of the transcription factor EB (TFEB), and reduced mTORC1 activity. Together, our data identify Trex1 as a regulator of lysosomal biogenesis and IFN-independent activation of antiviral genes, and shows dysregulation of lysosomes can elicit innate immune responses
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