2,481 research outputs found

    Private Function Evaluation with Cards

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    Card-based protocols allow to evaluate an arbitrary fixed Boolean function on a hidden input to obtain a hidden output, without the executer learning anything about either of the two (e.g., [12]). We explore the case where implements a universal function, i.e., is given the encoding ⟨⟩ of a program and an input and computes (⟨⟩,)=(). More concretely, we consider universal circuits, Turing machines, RAM machines, and branching programs, giving secure and conceptually simple card-based protocols in each case. We argue that card-based cryptography can be performed in a setting that is only very weakly interactive, which we call the “surveillance” model. Here, when Alice executes a protocol on the cards, the only task of Bob is to watch that Alice does not illegitimately turn over cards and that she shuffles in a way that nobody knows anything about the total permutation applied to the cards. We believe that because of this very limited interaction, our results can be called program obfuscation. As a tool, we develop a useful sub-protocol II_{II}↑ that couples the two equal-length sequences , and jointly and obliviously permutes them with the permutation ∈ that lexicographically minimizes (). We argue that this generalizes ideas present in many existing card-based protocols. In fact, AND, XOR, bit copy [37], coupled rotation shuffles [30] and the “permutation division” protocol of [22] can all be expressed as “coupled sort protocols”

    Intraguild aggressiveness between an alien and a native predatory mite

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    The predatory mite Amblydromalus limonicus, non-native in Europe, can be used legally in several European countries as greenhouse biocontrol agent against thrips species, although this species is also able to feed on whiteflies and gall mites. The first record of the unintended occurrence of A. limonicus in apple orchards in Europe comes from Catalonia (Spain), where A. limonicus is well established in the native predatory mite community since 2011. The dominant species in this community is Amblyseius andersoni, which has a similar life-style as A. limonicus (large, aggressive predator with broad diet range) making intraguild (IG) interactions between the two predators likely. Thus, we tested the IG aggressiveness of native and alien female predators, when provided with IG prey (larvae). Alien females of A. limonicus proved to be highly aggressive IG predators against native larvae of A. andersoni, which were attacked earlier and more frequently than alien larvae by the native predator. Nearly all attacks by the alien predator resulted in the death of native IG prey, whereas about 10% of the alien intraguild prey escaped the attacks of the native predator. Additionally, native IG prey is smaller than alien prey, which should facilitate the overwhelming by the alien predator. We argue that the strong aggressive intraguild behavior of A. limonicus is contributing to its establishment success in the native predatory mite community.info:eu-repo/semantics/acceptedVersio

    Sound Narrative: Honing a Deeper Understanding of Soundscapes

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    This essay reports on the pedagogical and curricular decisions guiding the creative activities in the author’s university course incorporating field recording, soundscape-based composition, and digital technology. In keeping with the issue’s theme of 21st-century composition, the article includes critical reflection and a consideration of the influence of R. Murray Schafer. It contextualizes the course in the broader context of modern compositional activities in university settings. The author’s creative practice informs much of the pedagogical framework as a soundscape-based composer

    Global citizenship as the completion of cosmopolitanism

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    A conception of global citizenship should not be viewed as separate from, or synonymous with, the cosmopolitan moral orientation, but as a primary component of it. Global citizenship is fundamentally concerned with individual moral requirements in the global frame. Such requirements, framed here as belonging to the category of individual cosmopolitanism, offer guidelines on right action in the context of global human community. They are complementary to the principles of moral cosmopolitanism – those to be used in assessing the justice of global institutions and practices – that have been emphasised by cosmopolitan political theorists. Considering principles of individual and moral cosmopolitanism together can help to provide greater clarity concerning individual duties in the absence of fully global institutions, as well as clarity on individual obligations of justice in relation to emerging and still-developing trans-state institutions

    Lightweight Acquisition and Ranging of Flows in the Data Plane

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    As networks get more complex, the ability to track almost all the flows is becoming of paramount importance. This is because we can then detect transient events impacting only a subset of the traffic. Solutions for flow monitoring exist, but it is getting very difficult to produce accurate estimations for every tuple given the memory constraints of commodity programmable switches. Indeed, as networks grow in size, more flows have to be tracked, increasing the number of tuples to be recorded. At the same time, end-host virtualization requires more specific flowIDs, enlarging the memory cost for every single entry. Finally, the available memory resources have to be shared with other important functions as well (e.g., load balancing, forwarding, ACL). To address those issues, we present FlowLiDAR (Flow Lightweight Detection and Ranging), a new solution that is capable of tracking almost all the flows in the network while requiring only a modest amount of data plane memory which is not dependent on the size of flowIDs. We implemented the scheme in P4, tested it using real traffic from ISPs and compared it against four state-of-the-art solutions: FlowRadar, NZE, PR-sketch, and Elastic Sketch. While those can only reconstruct up to 60% of the tuples, FlowLiDAR can track 98.7% of them with the same amount of memory

    PPR virus threatens wildlife conservation

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    Los medios de comunicación y el tatuaje contemporáneo

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    El fenómeno del tatuaje, inicialmente asociado a grupos étnicos tradicionales y más tarde a culturas marginales,ha tenido en las últimas décadas una expresión inédita en las sociedades contemporáneas extendiéndose entre sectores poblacionales muy diversos, antaño ajenos a esta práctica. Originariamente asociado a lo ritual y lo sagrado, ha devenido para algunos en elemento de moda impulsado por los canales de difusión mediada. Su presencia es evidente en las calles pero también en los medios de comunicación. En este artículo se aborda el papel de los medios de comunicación en este estado de cosas. En esta investigación se han realizado entrevistas en profundidad tanto a profesionales del tatuaje como a personas tatuadas para conocer los diversos aspectos implicados en la mediatización del tatuaje y en su ejecución. Como resultado de las entrevistas se ha podido constatar que los medios han incidido en la extensión de esta práctica, tanto desde la perspectiva evidente de su presencia cuantitativa en entornos urbanos cuanto desde los diferentes modos en los que la visibilidad que los media otorgan al tatuaje a través de diversas plataformas y formatos interviene en múltiples ámbitos que abarcan desde la formación de los tatuadores, los estilos visuales, la legitimación social de su uso, el significado personal que se da a los tatuajes y la modulación del relato en torno al hecho de tatuarse, entre otros
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