25,572 research outputs found

    Virtual Proofs of Reality

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    In this paper, we discuss the question how physical statements can be proven remotely over digital communication channels, but without using classical secret keys, and without assuming tamper-resistant and trusted measurement hardware in the location of the prover. Examples for the considered physical statements are: (i) “the temperature of a certain object is X °C”, (ii) “two certain objects are positioned at distance X”, or (iii) “a certain object has been irreversibly altered or destroyed”. In lack of an established name, we would like to call the corresponding security protocols ”virtual proofs of reality” (VPs). While a host of variants seems conceivable, this paper focuses on VPs in which the verifier has handed over one or more specific physical objects O_i to the prover at some point prior to the VP. These “witness objects” assist the prover during the proof, but shall not contain classical digital keys nor be assumed tamper-resistant in the classical sense. The prover is allowed to open, inspect and alter these objects in our adversarial model, only being limited by current technology, while he shall still be unable to prove false claims to the verifier. In order to illustrate our concept, we give example protocols built on temperature sensitive integrated circuits, disordered optical scattering media, and quantum systems. These protocols prove the temperature, destruction/modification, or relative position of witness objects in the prover’s location. Full experimental realizations of these schemes are beyond the scope of this paper. But the protocols utilize established technologies from the areas of physical unclonable functions and quantum cryptography, and hence appear plausible also without such proof. Finally, we also discuss potential advancements of our method in theory, for example “public virtual proofs” that function without exchanging witness objects Oi between the verifier and the prover. Our work touches upon and partly extends several established cryptographic and security concepts, including physical unclonable functions, quantum cryptography, and interactive proof systems

    Visualyzart Project – The role in education

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    The VisualYzARt project intends to develop research on mobile platforms, web and social scenarios in order to bring augmented reality and natural interaction for the general public, aiming to study and validate the adequacy of YVision platform in various fields of activity such as digital arts, design, education, culture and leisure. The VisualYzARt project members analysed the components available in YVision platform and are defining new ones that allow the creation of applications to a chosen activity, effectively adding a new language to the domain YVision. In this paper we will present the role of the InstitutoPolitĂ©cnico de SantarĂ©m which falls into the field of education.VisualYzART is funded by QREN – Sistema de Incentivos Ă  Investigação e Desenvolvimento TecnolĂłgico (SI I&DT), Project n. Âș 23201 - VisualYzARt (from January 2013 to December 2014). Partners: YDreams Portugal; Instituto PolitĂ©cnico de SantarĂ©m - Gabinete de e-Learning; Universidade de Coimbra - Centro de InformĂĄtica e Sistemas; Instituto PolitĂ©cnico de Leiria - Centro de Investigação em InformĂĄtica e ComunicaçÔes; Universidade CatĂłlica do Porto - Centro de Investigação em CiĂȘncia e Tecnologia das Artes.info:eu-repo/semantics/publishedVersio

    Virtual Evidence: A Constructive Semantics for Classical Logics

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    This article presents a computational semantics for classical logic using constructive type theory. Such semantics seems impossible because classical logic allows the Law of Excluded Middle (LEM), not accepted in constructive logic since it does not have computational meaning. However, the apparently oracular powers expressed in the LEM, that for any proposition P either it or its negation, not P, is true can also be explained in terms of constructive evidence that does not refer to "oracles for truth." Types with virtual evidence and the constructive impossibility of negative evidence provide sufficient semantic grounds for classical truth and have a simple computational meaning. This idea is formalized using refinement types, a concept of constructive type theory used since 1984 and explained here. A new axiom creating virtual evidence fully retains the constructive meaning of the logical operators in classical contexts. Key Words: classical logic, constructive logic, intuitionistic logic, propositions-as-types, constructive type theory, refinement types, double negation translation, computational content, virtual evidenc

    Digital exclusion: potential implications for social work education

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    QAA Subject Benchmark 5.9 requires social work students to demonstrate the ability to have a critical understanding of the social impact of ICT, including an awareness of the impact of the 'digital divide'. In the twenty-first century, the implications of digital exclusion may become increasingly relevant for the social work profession with its values of empowerment and anti-oppressive practices. As governments and organisations move closer to the provision of online services, the social worker may find themselves addressing the disempowerment of service users and carers disconnected from a virtual welfare state. The concern is that Benchmark 5.9 does not go far enough, that the full significance of this requirement may not be sufficiently realised and a greater awareness urgently called for

    Formulating Consciousness: A Comparative Analysis of Searle’s and Dennett’s Theory of Consciousness

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    This research will argue about which theory of mind between Searle’s and Dennett’s can better explain human consciousness. Initially, distinctions between dualism and materialism will be discussed ranging from substance dualism, property dualism, physicalism, and functionalism. In this part, the main issue that is tackled in various theories of mind is revealed. It is the missing connection between input stimulus (neuronal reactions) and behavioral disposition: consciousness. Then, the discussion will be more specific on Searle’s biological naturalism and Dennett’s multiple drafts model as the two attempted to answer the issue. The differences between them will be highlighted and will be analyzed according to their relation to their roots: dualism and materialism. The two theories will be examined on how each answer the questions on consciousness

    Open educational resources : conversations in cyberspace

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    172 p. : ill. ; 25 cm.Libro ElectrónicoEducation systems today face two major challenges: expanding the reach of education and improving its quality. Traditional solutions will not suffice, especially in the context of today's knowledge-intensive societies. The Open Educational Resources movement offers one solution for extending the reach of education and expanding learning opportunities. The goal of the movement is to equalize access to knowledge worldwide through openly and freely available online high-quality content. Over the course of two years, the international community came together in a series of online discussion forums to discuss the concept of Open Educational Resources and its potential. This publication makes the background papers and reports from those discussions available in print.--Publisher's description.A first forum : presenting the open educational resources (OER) movement. Open educational resources : an introductory note / Sally Johnstone -- Providing OER and related issues : an introductory note / Anne Margulies, ... [et al.] -- Using OER and related issues : in introductory note / Mohammed-Nabil Sabry, ... [et al.] -- Discussion highlights / Paul Albright -- Ongoing discussion. A research agenda for OER : discussion highlights / Kim Tucker and Peter Bateman -- A 'do-it-yourself' resource for OER : discussion highlights / Boris Vukovic -- Free and open source software (FOSS) and OER -- A second forum : discussing the OECD study of OER. Mapping procedures and users / Jan Hylén -- Why individuals and institutions share and use OER / Jan Hylén -- Discussion highlights / Alexa Joyce -- Priorities for action. Open educational resources : the way forward / Susan D'Antoni
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