272 research outputs found

    EVIL: Exploiting Software via Natural Language

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    Writing exploits for security assessment is a challenging task. The writer needs to master programming and obfuscation techniques to develop a successful exploit. To make the task easier, we propose an approach (EVIL) to automatically generate exploits in assembly/Python language from descriptions in natural language. The approach leverages Neural Machine Translation (NMT) techniques and a dataset that we developed for this work. We present an extensive experimental study to evaluate the feasibility of EVIL, using both automatic and manual analysis, and both at generating individual statements and entire exploits. The generated code achieved high accuracy in terms of syntactic and semantic correctness

    Systems-theoretic Safety Assessment of Robotic Telesurgical Systems

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    Robotic telesurgical systems are one of the most complex medical cyber-physical systems on the market, and have been used in over 1.75 million procedures during the last decade. Despite significant improvements in design of robotic surgical systems through the years, there have been ongoing occurrences of safety incidents during procedures that negatively impact patients. This paper presents an approach for systems-theoretic safety assessment of robotic telesurgical systems using software-implemented fault-injection. We used a systemstheoretic hazard analysis technique (STPA) to identify the potential safety hazard scenarios and their contributing causes in RAVEN II robot, an open-source robotic surgical platform. We integrated the robot control software with a softwareimplemented fault-injection engine which measures the resilience of the system to the identified safety hazard scenarios by automatically inserting faults into different parts of the robot control software. Representative hazard scenarios from real robotic surgery incidents reported to the U.S. Food and Drug Administration (FDA) MAUDE database were used to demonstrate the feasibility of the proposed approach for safety-based design of robotic telesurgical systems.Comment: Revise based on reviewers feedback. To appear in the the International Conference on Computer Safety, Reliability, and Security (SAFECOMP) 201

    Response of the Pacific Sector of the Southern Ocean to wind stress variability from 1995 to 2017

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    AbstractDrifter, satellite, expendable bathythermograph (XBT), and Argo float data are used to study the response of the Pacific Sector of the Southern Ocean (PSSO) to the wind stress field in the period 1995–2017, in terms of eddy field, water mass transport, and heat fluxes at large and regional scales. Increasing wind stress over the PSSO in those two decades led to a growth of the Eddy Kinetic Energy (EKE) in the region of the Antarctic Circumpolar Current (ACC). Increases of the EKE occur with delays of 1–4 years with respect to peaks in the zonal component of the wind stress. The persistent ACC meander located south of New Zealand (between 150°E and 180°W and 50°S to 66°S) responds to the interannual wind variations earlier than the entire ACC branch in the PSSO. In the same area, an estimate of the ACC transport based on in situ data shows interannual variability but no significant decadal trend over the study period. The effects of the EKE variability on the meridional eddy heat fluxes are significant on interannual scales. The strengthening of the EKE field leads to a local increase in the poleward meridional eddy heat fluxes in the PSSO, especially in the ACC band. The weakening of the EKE field defines an area of equatorward meridional eddy heat fluxes in the middle of the PSSO (south of 40°S, between 130°W and 160°W) and prevalent poleward fluxes in the further western and eastern regions

    Thin-shell plastic lenses for space and laboratory applications

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    We have identified an inexpensive, readily available, mechanically stable, extremely smooth, elastic, and mechanically uniform plastic suitable for thin film X-ray optics. Polyethylene terephthalate (PET) is easily deformed without losing its elastic properties or surface smoothness. Most important, PET can be coated with mono- or multilayers that reflect X-rays at grazing incidence. We have used these properties to produce X-ray optics made either as a concentric nest of cylinders or as a spiral. We have produced accurately formed shells in precisely machined vacuum mandresl or used a pin and wheel structure to form a continuously wound spiral. The wide range of medical, industrial and scientific applications for our technology includes: a monochromatic X-ray collimater for medical diagnostics, a relay optic to transport an X-ray beam from the target in a scanning electron microscop0e to a lithium-drifted silicon and microcalorimeter detectors and a satellite mounted telescope to collect celestial X-rays. A wide variety of mono- and multilayer coatings allow X-rays up to ~100 keV to be reflected. Our paper presents data from a variety of diagnostic measurements on the properties of the PET foil and imaging results form single- and multi-shell lenses

    Advancements in ion beam figuring of very thin glass plates

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    The high-quality surface characteristics, both in terms of figure error and of micro-roughness, required on the mirrors of a high angular resolution x-ray telescope are challenging, but in principle well suited with a deterministic and non-contact process like the ion beam figuring. This process has been recently proven to be compatible even with very thin (thickness around 0.4mm) sheet of glasses (like D263 and Eagle). In the last decade, these types of glass have been investigated as substrates for hot slumping, with residual figure errors of hundreds of nanometres. In this view, the mirrors segments fabrication could be envisaged as a simple two phases process: a first replica step based on hot slumping (direct/indirect) followed by an ion beam figuring which can be considered as a post-fabrication correction method. The first ion beam figuring trials, realized on flat samples, showed that the micro-roughness is not damaged but a deeper analysis is necessary to characterize and eventually control/compensate the glass shape variations. In this paper, we present the advancements in the process definition, both on flat and slumped glass samples

    Progress in ion beam figuring of very thin slumped glass plates for lightweight x-ray telescope

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    The combination of the hot slumping and the Ion Beam Figuring (IBF) technologies can be a very competitive solution for the realization of x-ray optics with excellent imaging capabilities and high throughput. While very thin mirrors segments can be realized by slumping with residual figure errors below few hundreds of nanometres, a non-contact and deterministic process (dependent on dwell time), like IBF, is a very effective post facto correction, as it avoids all the problems due to the handling and the supporting system. In the last years, the two processes were proven compatible with very thin sheet of Eagle XG glasses (0.4 mm thickness). Nevertheless, the fast convergence of the process is a key factor to limit the cost of the mirror plate production. A deeper characterization of removal function stability showed that its repeatability between each run has to be improved for a real enhancement of the process convergence factor. A new algorithm based on de-convolution has been implemented and tested, with important advantages in terms of calculation speed, minimum material removal and optimization possibilities. By analysing the metrological data of test slumped glasses, we showed how the IBF is effective in the correction of figure errors on scales above 8 - 10 mm. An overall figuring time of few hours is required with surface error around 100 nm rms. Thanks to the thickness measurement data, which are performed in transmission mode with an interferometric set-up, we demonstrated that it is possible to disentangle the effective amount of the material removed and the deformations introduced during the process

    The future of Cybersecurity in Italy: Strategic focus area

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    This volume has been created as a continuation of the previous one, with the aim of outlining a set of focus areas and actions that the Italian Nation research community considers essential. The book touches many aspects of cyber security, ranging from the definition of the infrastructure and controls needed to organize cyberdefence to the actions and technologies to be developed to be better protected, from the identification of the main technologies to be defended to the proposal of a set of horizontal actions for training, awareness raising, and risk management

    Pensando un rediseño de agroecosistemas campesinos del Chaco Semiárido argentino: el caso de la asociación campesinos del Valle del Conlara (San Luis, Argentina)

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    La expansión del modelo de agricultura industrial en la región chaqueña ha generado fuertes cambios ambientales y sociales (desmontes masivos, pérdida de biodiversidad, expulsión de campesinos). Desde 2009, estudiantes, docentes e investigadores de la Universidad de Buenos Aires trabajan junto a campesinos y técnicos locales de la Asociación Campesinos del Valle del Conlara (San Luis, Argentina; ACVC), en pensar cómo mejorar la cantidad, calidad y estabilidad de la oferta forrajera del monte nativo. Partimos de una caracterización preliminar de los agroecosistemas campesinos, publicada en SOCLA (2013). Aquí, nos proponemos compartir las reflexiones sobre alternativas de rediseño y manejo agroecológico, así como los trabajos que se realizaron en la ACVC en este sentido. Este trabajo se enmarca dentro de un proyecto interdisciplinario, cuyo propósito es contribuir al fortalecimiento de la autonomía ecológica y económica de los campesinos, una alternativa al modelo hegemónico.Eje: B5 Sistemas de conocimiento (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale

    Pensando un rediseño de agroecosistemas campesinos del Chaco Semiárido argentino: el caso de la asociación campesinos del Valle del Conlara (San Luis, Argentina)

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    La expansión del modelo de agricultura industrial en la región chaqueña ha generado fuertes cambios ambientales y sociales (desmontes masivos, pérdida de biodiversidad, expulsión de campesinos). Desde 2009, estudiantes, docentes e investigadores de la Universidad de Buenos Aires trabajan junto a campesinos y técnicos locales de la Asociación Campesinos del Valle del Conlara (San Luis, Argentina; ACVC), en pensar cómo mejorar la cantidad, calidad y estabilidad de la oferta forrajera del monte nativo. Partimos de una caracterización preliminar de los agroecosistemas campesinos, publicada en SOCLA (2013). Aquí, nos proponemos compartir las reflexiones sobre alternativas de rediseño y manejo agroecológico, así como los trabajos que se realizaron en la ACVC en este sentido. Este trabajo se enmarca dentro de un proyecto interdisciplinario, cuyo propósito es contribuir al fortalecimiento de la autonomía ecológica y económica de los campesinos, una alternativa al modelo hegemónico.Eje: B5 Sistemas de conocimiento (Relatos de experiencias)Facultad de Ciencias Agrarias y Forestale
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