1,237 research outputs found

    Obligations of trust for privacy and confidentiality in distributed transactions

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    Purpose – This paper aims to describe a bilateral symmetric approach to authorization, privacy protection and obligation enforcement in distributed transactions. The authors introduce the concept of the obligation of trust (OoT) protocol as a privacy assurance and authorization mechanism that is built upon the XACML standard. The OoT allows two communicating parties to dynamically exchange their privacy and authorization requirements and capabilities, which the authors term a notification of obligation (NoB), as well as their commitments to fulfilling each other's requirements, which the authors term signed acceptance of obligations (SAO). The authors seek to describe some applicability of these concepts and to show how they can be integrated into distributed authorization systems for stricter privacy and confidentiality control. Design/methodology/approach – Existing access control and privacy protection systems are typically unilateral and provider-centric, in that the enterprise service provider assigns the access rights, makes the access control decisions, and determines the privacy policy. There is no negotiation between the client and the service provider about which access control or privacy policy to use. The authors adopt a symmetric, more user-centric approach to privacy protection and authorization, which treats the client and service provider as peers, in which both can stipulate their requirements and capabilities, and hence negotiate terms which are equally acceptable to both parties. Findings – The authors demonstrate how the obligation of trust protocol can be used in a number of different scenarios to improve upon the mechanisms that are currently available today. Practical implications – This approach will serve to increase trust in distributed transactions since each communicating party receives a difficult to repudiate digitally signed acceptance of obligations, in a standard language (XACML), which can be automatically enforced by their respective computing machinery. Originality/value – The paper adds to current research in trust negotiation, privacy protection and authorization by combining all three together into one set of standardized protocols. Furthermore, by providing hard to repudiate signed acceptance of obligations messages, this strengthens the legal case of the injured party should a dispute arise

    FEDERAL CIRCUIT SECOND AMENDMENT DEVELOPMENTS 2018

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    This Article provides a summary of federal circuit court cases decided in 2018. By the end of 2018, every circuit except for the Eighth has adopted a Two-Part Test for Second Amendment cases. In Part One, the court determines whether the challenged law burdens the Second Amendment right. If so, the court applies heightened scrutiny in Part Two. Courts in Second Amendment cases almost always apply intermediate scrutiny, but strict scrutiny and categorical invalidation are also available. The Two-Part Test is detailed in our article, The Federal Circuits’ Second Amendment Doctrines.[1] That article reviews every federal circuit Second Amendment case after District of Columbia v. Heller (2008), up to approximately August 2016. [1] David B. Kopel & Joseph G.S. Greenlee, The Federal Circuits Second Amendment Doctrines, 61 St. Louis U. L.J. 193 (2017) (cited in Pena v. Lindley, 898 F.3d 969, 1004 (9th Cir. 2018) (Bybee, J., dissenting))

    Quantum correlations in position, momentum, and intermediate bases for a full optical field of view

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    We report an eight-element, linear-array, single-photon detector that uses multiple fibers of differing lengths coupled to a single detector, the timing information from which reveals the position in which the photon was measured. Using two such arrays and two detectors we measure the correlations of photons produced by parametric downconversion, without recourse to mechanical scanning. Spatial light modulators acting as variable focal length lenses positioned between the downconversion crystal and the arrays allow us to switch between measurement of position, transverse momentum, or intermediate bases. We observe the product of the variances of the conditional probabilities for position and momentum to be more than an order of magnitude below the classical limit, realizing a full-field demonstration of the Einstein-Podolsky-Rosen paradox. Such, multistate measurement technologies allow access to the higher information content of the photon based upon spatial modes

    2d gravity stress tensor and the problem of the calculation of the multi-loop amplitudes in the string theory

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    It is shown that the vacuum value of the 2d2d gravity stress tensor in the free field theory is singular in the fundamental region on the complex plane where the genus-n>1n>1 Riemann surface are mapped. Because of the above singularity, one can not construct modular invariant multi-loop amplitudes. The discussed singularity is due to the singularity in the vacuum value of the 2d2d gravity field that turns out to be on the genus-n>1n>1 Riemann surfaces.Comment: 13 pages, LATEX, November 199

    Portable implementation of a quantum thermal bath for molecular dynamics simulations

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    Recently, Dammak and coworkers (H. Dammak, Y. Chalopin, M. Laroche, M. Hayoun, and J.J. Greffet. Quantumthermal bath for molecular dynamics simulation. Phys. Rev. Lett., 103:190601, 2009.) proposed that the quantum statistics of vibrations in condensed systems at low temperature could be simulated by running molecular dynamics simulations in the presence of a colored noise with an appropriate power spectral density. In the present contribution, we show how this method can be implemented in a flexible manner and at a low computational cost by synthesizing the corresponding noise 'on the fly'. The proposed algorithm is tested for a simple harmonic chain as well as for a more realistic model of aluminium crystal. The energy and Debye-Waller factor are shown to be in good agreement with those obtained from harmonic approximations based on the phonon spectrum of the systems. The limitations of the method associated with anharmonic effects are also briefly discussed. Some perspectives for disordered materials and heat transfer are considered.Comment: Accepted for publication in Journal of Statistical Physic

    A comparative study of the effects of four treatment regimes on ivermectin efficacy, body weight and pasture contamination in lambs naturally infected with gastrointestinal nematodes in Scotland

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    AbstractRefugia-based drenching regimes have been widely recommended to slow development of anthelmintic resistance but there are few comparisons between different treatment approaches in the UK. The impact of four ivermectin treatment regimes on drug efficacy, lamb body weight and nematode contamination during a 154 day grazing season were evaluated in a consecutive five year field study. Regimes were whole-flock treatment every 4weeks (NST), targeted selective treatment (TST) based on individual performance, strategic whole-flock treatments at pre-determined times (SPT) or whole-flock treatment when clinical signs were apparent (MT). Mean numbers of ivermectin drenches administered per season were 4.0, 1.8, 2.0 and 1.4 for NST, TST, SPT and MT groups, respectively. The mean anthelmintic efficacy (AE) for each treatment group was based on faecal egg count reduction post-treatment employing a bootstrap sampling based algorithm. Mean AE was 95–98% for all groups in 2006 and mean AE (95% confidence limits) for NST declined to 62% (55%, 68%) in 2010. In comparison, AE for TST, SPT and MT in 2010 were 86% (81%, 92%), 86% (83%, 90%) and 83% (78%, 88%), respectively. Body weight in TST and SPT was similar to NST in all years (p>0.05), however MT lambs were lighter than NST in 2006–2008 (p⩽0.04). Tracer lamb worm burdens was lowest in NST but was not significantly different between other groups. Overall, both the TST and SPT regimes appeared to maintain animal performance and conserve anthelmintic efficacy compared with a neo-suppressive anthelmintic treatment regime

    Using a cognitive architecture to examine what develops

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    Different theories of development propose alternative mechanisms by which development occurs. Cognitive architectures can be used to examine the influence of each proposed mechanism of development while keeping all other mechanisms constant. An ACT-R computational model that matched adult behavior in solving a 21-block pyramid puzzle was created. The model was modified in three ways that corresponded to mechanisms of development proposed by developmental theories. The results showed that all the modifications (two of capacity and one of strategy choice) could approximate the behavior of 7-year-old children on the task. The strategy-choice modification provided the closest match on the two central measures of task behavior (time taken per layer, r = .99, and construction attempts per layer, r = .73). Modifying cognitive architectures is a fruitful way to compare and test potential developmental mechanisms, and can therefore help in specifying “what develops.

    Cultural robotics : The culture of robotics and robotics in culture

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    Copyright 2013 Samani et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly citedIn this paper, we have investigated the concept of "Cultural Robotics" with regard to the evolution o social into cultural robots in the 21st Century. By defining the concept of culture, the potential development of culture between humans and robots is explored. Based on the cultural values of the robotics developers, and the learning ability of current robots, cultural attributes in this regard are in the process of being formed, which would define the new concept of cultural robotics. According to the importance of the embodiment of robots in the sense of presence, the influence of robots in communication culture is anticipated. The sustainability of robotics culture based on diversity for cultural communities for various acceptance modalities is explored in order to anticipate the creation of different attributes of culture between robot and humans in the futurePeer reviewe

    Rigorous results on superconducting ground states for attractive extended Hubbard models

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    We show that the exact ground state for a class of extended Hubbard models including bond-charge, exchange, and pair-hopping terms, is the Yang "eta-paired" state for any non-vanishing value of the pair-hopping amplitude, at least when the on-site Coulomb interaction is attractive enough and the remaining physical parameters satisfy a single constraint. The ground state is thus rigorously superconducting. Our result holds on a bipartite lattice in any dimension, at any band filling, and for arbitrary electron hopping.Comment: 12 page
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