25,572 research outputs found
Virtual Proofs of Reality
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) âthe temperature of a certain object is X
°Câ, (ii) âtwo certain objects are positioned at distance Xâ, or (iii) âa certain object has been irreversibly altered or destroyedâ. In lack of an established name, we would like to call the corresponding security protocols âvirtual proofs of realityâ (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 âwitness objectsâ 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 proverâs 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 âpublic virtual proofsâ 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 â The role in education
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 â 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
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
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 Searleâs and Dennettâs Theory of Consciousness
This research will argue about which theory of mind between
Searleâs and Dennettâs 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 Searleâs biological naturalism and Dennettâs 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
172 p. : ill. ; 25 cm.Libro ElectrĂłnicoEducation 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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