184 research outputs found

    Clarity: An Exploration of Semantic Information Encoded in Mobile Application GUIs

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    Upon installing a mobile application, human beings are able, to a great extent, to know immediately what the subcomponents of the screen do. They know what buttons return them to the previous screen, which ones submit their log in information, and which brings up the menu. This is the result of a combination of intuitive design and cross-platform design standards which allow users to draw on previous experience. Regardless, the fact that humans are able to understand the functionality of screen components at a glance suggests that there is semantic information encode into a mobile application’s GUI. In this work, we present an automated approach to exploring the nature of the semantic information encoded into the GUI of a mobile application. We do this using three modalities (1) a screenshot of an image, (2) text descriptions of the functionality of GUI components sourced through Amazon’s Mechanical Turk, and (3) parsed information from the screen hierarchy’s XML dump. The first two modalities are aligned using a convolutional neural network, which detects objects in the screenshot and extracts salient features, paired with a bidirectional recurrent neural network which serves as a language model. Both of these models maps their respective modalities to a semantic space, and then aligns the two representations in that space. The third modality is incorporated by using a Seq2Seq model which maps the screen’s XML dump directly to reasonable descriptions of the functionality of the screen. Our experiments reveal that semantic information extracted from the above representations of the GUI of a mobile application is comparable to that of real-world images such as those found in the MSCOCO dataset. In this work, we compare our results to similar models trained on this dataset, and compare the results from different screen representations against each other

    Experimental exposure to urban and pink noise affects brain development and song learning in zebra finches (Taenopygia guttata)

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    Recently, numerous studies have observed changes in bird vocalizations-especially song-in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers\u27 songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats

    Experimental Exposure to Urban and Pink Noise Affects Brain Development and Song Learning in Zebra Finches (Taenopygia guttata)

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    Recently, numerous studies have observed changes in bird vocalizations—especially song—in urban habitats. These changes are often interpreted as adaptive, since they increase the active space of the signal in its environment. However, the proximate mechanisms driving cross-generational changes in song are still unknown. We performed a captive experiment to identify whether noise experienced during development affects song learning and the development of song-control brain regions. Zebra finches (Taeniopygia guttata) were bred while exposed, or not exposed, to recorded traffic urban noise (Study 1) or pink noise (Study 2). We recorded the songs of male offspring and compared these to fathers’ songs. We also measured baseline corticosterone and measured the size of song-control brain regions when the males reached adulthood (Study 1 only). While male zebra finches tended to copy syllables accurately from tutors regardless of noise environment, syntax (the ordering of syllables within songs) was incorrectly copied affected by juveniles exposed to noise. Noise did not affect baseline corticosterone, but did affect the size of brain regions associated with song learning: these regions were smaller in males that had been had been exposed to recorded traffic urban noise in early development. These findings provide a possible mechanism by which noise affects behaviour, leading to potential population differences between wild animals occupying noisier urban environments compared with those in quieter habitats

    Post-Quantum Hash-Based Signatures for Secure Boot

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    The potential development of large-scale quantum computers is raising concerns among IT and security research professionals due to their ability to solve (elliptic curve) discrete logarithm and integer factorization problems in polynomial time. All currently used, public-key cryptography algorithms would be deemed insecure in a post-quantum setting. In response, the United States National Institute of Standards and Technology has initiated a process to standardize quantum-resistant cryptographic algorithms, focusing primarily on their security guarantees. Additionally, the Internet Engineering Task Force has published two quantum-secure signature schemes and has been looking into adding quantum-resistant algorithms in protocols. In this work, we investigate two post-quantum, hash-based signature schemes published by the Internet Engineering Task Force and submitted to the National Institute of Standards and Technology for use in secure boot. We evaluate various parameter sets for the use-cases in question and we prove that post-quantum signatures would not have material impact on image signing. We also study the hierarchical design of these signatures in different scenarios of hardware secure boot

    Post-Quantum LMS and SPHINCS+ Hash-Based Signatures for UEFI Secure Boot

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    The potential development of large-scale quantum computers is raising concerns among IT and security research professionals due to their ability to solve (elliptic curve) discrete logarithm and integer factorization problems in polynomial time. This would jeopardize IT security as we know it. In this work, we investigate two quantum-safe, hash-based signature schemes published by the Internet Engineering Task Force and submitted to the National Institute of Standards and Technology for use in secure boot. We evaluate various parameter sets for the use-case in question and we prove that post-quantum signatures with less than one second signing and less than 10ms verification would not have material impact (less than1‰) on secure boot. We evaluate the hierarchical design of these signatures in hardware-based and virtual secure boot. In addition, we develop Hardware Description Language code and show that the code footprint is just a few kilobytes in size which would fit easily in almost all modern FPGAs. We also analyze and evaluate potential challenges for integration in existing technologies and we discuss considerations for vendors embarking on a journey of image signing with hash-based signatures

    Curcumin and Graphene Oxide Incorporated into Alginate Hydrogels as Versatile Devices for the Local Treatment of Squamous Cell Carcinoma

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    With the aim of preparing hybrid hydrogels suitable for use as patches for the local treatment of squamous cell carcinoma (SCC)-affected areas, curcumin (CUR) was loaded onto graphene oxide (GO) nanosheets, which were then blended into an alginate hydrogel that was crosslinked by means of calcium ions. The homogeneous incorporation of GO within the polymer network, which was confirmed through morphological investigations, improved the stability of the hybrid system compared to blank hydrogels. The weight loss in the 100–170 °C temperature range was reduced from 30% to 20%, and the degradation of alginate chains shifted to higher temperatures. Moreover, GO enhanced the stability in water media by counteracting the de-crosslinking process of the polymer network. Cell viability assays showed that the loading of CUR (2.5% and 5% by weight) was able to reduce the intrinsic toxicity of GO towards healthy cells, while higher amounts were ineffective due to the antioxidant/prooxidant paradox. Interestingly, the CUR-loaded systems were found to possess a strong cytotoxic effect in SCC cancer cells, and the sustained CUR release (~50% after 96 h) allowed long-term anticancer efficiency to be hypothesized

    Pluto Integrated Camera-Spectrometer (PICS): A Low Mass, Low Power Instrument for Planetary Exploration

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    The concept we describe is an integrated instrument (a Pluto Integrated Camera Spectrometer, PICS) that will perform the functions of all three optical instruments required by the Pluto Fast Flyby Mission: the near-IR spectrometer, the camera, and the UV spectrometer. This integrated approach minimizes mass and power use. It also forced us early in the conceptual design to consider integrated observational sequences and integrated power management, thus ensuring compatible duty cycles (i.e. exposure times, readout rates) to meet the composite requirements for data collection, compression, and storage. Based on flight mission experience we believe that this integrated approach will result in substantial cost savings, both in reworking instrument designs during accommodation, as well as in sequence planning and integration. Finally, this integrated payload automatically yields a cohesive mission data set, optimized for correlative analysis. In our baseline concept, a single set of lightweight, multi-wavelength foreoptics is shared by an UV imaging spectrometer (160 spectral channels 10-150 nm), a two-CCD visible imaging system (simultaneously shuttered in two colors 300-500 nm and 500-1000 nm), and a near-IR imaging spectrometer (256 spectral channels 1300-2600 nm), The entire structure and optics is built from SiC, and includes an integrated radiator for thermal control. The design has no moving parts and each spectrometer covers a single octave in wavelength. For the Pluto mission, a separate port (aligned in a direction compatible with the radio occultation experiment) is provided for PICS measurement of a UV solar occultation and for spectral radiance calibration of the IR and visible subsystems. The integrated science this instrument will yield meets or exceeds all of the Priority-1A science objectives and captures many Priority-1B science objectives as well. The presentation will provide details of the PICS instrument design and describe the fabrication and testing of the integrated SiC structure and optics at SSG Inc. Final integration and test plans for the prototype will also be described

    Tracking the surface atomic motion in a coherent phonon oscillation

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    X-ray photoelectron diffraction is a powerful tool for determining the structure of clean and adsorbate-covered surfaces. Extending the technique into the ultrafast time domain will open the door to studies as diverse as the direct determination of the electron-phonon coupling strength in solids and the mapping of atomic motion in surface chemical reactions. Here we demonstrate time-resolved photoelectron diffraction using ultrashort soft X-ray pulses from the free electron laser FLASH. We collect Se 3d photoelectron diffraction patterns over a wide angular range from optically excited Bi2_2Se3_3 with a time resolution of 140 fs. Combining these with multiple scattering simulations allows us to track the motion of near-surface atoms within the first 3 ps after triggering a coherent vibration of the A1g_{1g} optical phonons. Using a fluence of 4.2 mJ/cm2^2 from a 1.55 eV pump laser, we find the resulting coherent vibrational amplitude in the first two interlayer spacings to be on the order of 1 pm
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