4,116 research outputs found

    Aerospace Medicine and Biology: A continuing bibliography with indexes (supplement 314)

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    This bibliography lists 139 reports, articles, and other documents introduced into the NASA scientific and technical information system in August, 1988

    Light Unmanned Aerial Vehicles (UAVs) for cooperative inspection of PV plants

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    After a fast photovoltaic (PV) expansion in the past decade supported by many governments in Europe, in this postincentive era, one of the most significant open issues in the PV sector is to find appropriate inspection methods to evaluate real PV plant performance and failures. In this context, PV modules are surely the key components affecting the overall system performance; therefore, there is a main concern about the occurrence of any kind of failure in PV modules. This paper aims to propose a novel concept for monitoring PV plants by using light unmanned aerial vehicles (UAVs) or systems (UASs) during their operation and maintenance. The main objectives of this study are to explore and evaluate the use of different UAV technologies and to propose a reliable, cost-effective, and time-saving method for the inspection of PV plants. In this research, different UAVs were employed to inspect a PV array field. For this purpose, some thermal imaging cameras and a visual camera were chosen as monitoring tools to suitably scan PV modules. The first results show that the procedure of utilizing UAV was effective in the detection of different failures of PV modules. Moreover, such a process was much faster and cost effective than traditional methods

    In the cities of the beyond: an interview with Paul Virilio

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    At the request of Open, the cultural theoretician John Armitage interviewed the French urbanist and philosopher Paul Virilio (b. 1932, Paris). A discussion on the future of the city

    Future schistosome hybridizations: Will all Schistosoma haematobium hybrids please stand-up!

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    nterrogating the genetic make-up of schistosome larvae (i.e. eggs, miracidia and cercariae) originating from definitive or intermediate snail hosts with molecular DNA methods has, by noting unexpected inter-species hybrids, started a revolution in our appraisal of African schistosomiasis [1-4]. Here, two dominant species of human schistosome exist, Schistosoma haematobium and S. mansoni, which are transmitted by specific intermediate freshwater snails, Bulinus spp. for the former and Biomphalaria spp. for the latter. The two schistosomes cause either urogenital or intestinal schistosomiasis, respectively [5] and depending on local snail distributions, schistosome transmission zones in the aquatic habitat may or may not overlap [6]. Within the S. haematobium group, a further 8 sister species are described with S. intercalatum and S. guineensis of medical importance, causing intestinal schistosomiasis while others, such as S. bovis, S. curassoni and S. mattheei occur in livestock, with the remaining species infecting wildlife. Schistosoma mattheei is also of medical interest for occasional infection and associated disease [7]. In contrast, S. mansoni has a single sister species, S. rodhaini, typically found in small rodents which can hybridise with S. mansoni, if given sufficient opportunity [2]

    Visual Servoing NMPC Applied to UAVs for Photovoltaic Array Inspection

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    The photovoltaic (PV) industry is seeing a significant shift toward large-scale solar plants, where traditional inspection methods have proven to be time-consuming and costly. Currently, the predominant approach to PV inspection using unmanned aerial vehicles (UAVs) is based on photogrammetry. However, the photogrammetry approach presents limitations, such as an increased amount of useless data during flights, potential issues related to image resolution, and the detection process during high-altitude flights. In this work, we develop a visual servoing control system applied to a UAV with dynamic compensation using a nonlinear model predictive control (NMPC) capable of accurately tracking the middle of the underlying PV array at different frontal velocities and height constraints, ensuring the acquisition of detailed images during low-altitude flights. The visual servoing controller is based on the extraction of features using RGB-D images and the Kalman filter to estimate the edges of the PV arrays. Furthermore, this work demonstrates the proposal in both simulated and real-world environments using the commercial aerial vehicle (DJI Matrice 100), with the purpose of showcasing the results of the architecture. Our approach is available for the scientific community in: https://github.com/EPVelasco/VisualServoing_NMPCComment: This paper is under review at the journal "IEEE Robotics and Automation Letters

    ADOPTING IMMUNOLOGICAL METAPHORS IN CYBERSECURITY APPLICATIONS

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    The evolution of the computer virus remains constant, yet the metaphors used to explain the abstract ideas of computer science remain static. Previous cybersecurity research frames issues of security in physical security metaphors, using tangible ideas or icons, such as castles, to illustrate the need for defense-in-depth models for computer security. Research confirms that security techniques drawn from the castle metaphor serve to prevent infection by a previously identified variant of the virus, but those techniques are weak against novel strain or zero-day exploit. This thesis set out to answer the following question: What role can metaphors from emergent fields play in augmenting the dominant metaphors in cybersecurity applications? This research found metaphors provide limits for defenses and often carry assumptions about system design with them, allowing exploitation in unusual ways. When attacking computer systems designed around physical security models, malicious actors may take advantage of a system’s inherent weak points, and infection is inevitable in any networked system. Because complex attacks cannot be prevented by adopting ideas from a single metaphor or discipline of study, this thesis proposes reimagining cybersecurity threats through a wide variety of metaphorical lenses and adopting a plurality of defenses to augment physical security or defense-in-depth metaphors when addressing wicked problems in cybersecurity applications.Civilian, Department of Homeland SecurityApproved for public release. Distribution is unlimited
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