1,216 research outputs found
Trusted-HB: a low-cost version of HB+ secure against Man-in-The-Middle attacks
Since the introduction at Crypto'05 by Juels and Weis of the protocol HB+, a
lightweight protocol secure against active attacks but only in a detection
based-model, many works have tried to enhance its security. We propose here a
new approach to achieve resistance against Man-in-The-Middle attacks. Our
requirements - in terms of extra communications and hardware - are surprisingly
low.Comment: submitted to IEEE Transactions on Information Theor
Depletion interactions of non-spherical colloidal particles in polymer solutions
We consider anisotropic colloidal particles immersed in a solution of long,
flexible, and nonadsorbing polymers. For the dumbbell shapes of recently
synthesized particles consisting of two intersecting spheres and for
lens-shaped particles with spherical surfaces we calculate the isotropic and
anisotropic interaction parameters that determine the immersion free energy and
the orientation-dependent depletion interaction between particles that are
induced by the polymers. Exact results are obtained for random-walk like
(ideal) polymer chains
Dresselhaus spin-orbit coupling in [111]-oriented semiconductor nanowires
The contribution of bulk inversion asymmetry to the total spin-orbit coupling
is commonly neglected for group III-V nanowires grown in the generic [111]
direction. We have solved the complete Hamiltonian of the circular nanowire
accounting for bulk inversion asymmetry via exact numerical diagonalization.
Three different symmetry classes of angular momentum states exist, which
reflects the threefold rotation symmetry of the crystal lattice about the [111]
axis. A particular group of angular momentum states contains degenerate modes
which are strongly coupled via the Dresselhaus Hamiltonian, which results in a
significant energy splitting with increasing momentum. Hence, under certain
conditions Dresselhaus spin-orbit coupling is relevant for [111] InAs and [111]
InSb nanowires. We demonstrate momentum-dependent energy splittings and the
impact of Dresselhaus spin-orbit coupling on the dispersion relation. In view
of possible spintronics applications relying on bulk inversion asymmetry we
calculate the spin expectation values and the spin texture as a function of the
Fermi energy. Finally, we investigate the effect of an axial magnetic field on
the energy spectrum and on the corresponding spin polarization.Comment: 11 Pages, 7 figure
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Coach and athlete perceptions of ambiguous behaviors and sexual harassment
The purpose of this study was to examine the perceptions of coaches and athletes of ambiguous behaviors (i.e. actions which may or may not be construed as sexual harassment) in order to inform curriculum development in coach education. This study replicates and extends a previous American study which examined perceptions and experiences of sexual harassment among 210 female college athletes in the USA (Volkwein, et al., 1997). The Americans’ research design was based on earlier work in education by Garlick (1994). The present study is the first, large-scale UK survey of sexual harassment among student athletes (n = 311) and coaches (n = 182). A sexual harassment questionnaire (Garlick, 1994) was adapted to a sport setting and UK context. The questionnaire contained statements regarding 19 ambiguous behaviors. Factor analysis identified four subcategories of the questionnaire: Invitations/1-to-1; Social enquiries; Invasion of personal space; Personal Enquiries. A 2 x 2 (Gender by Role) MANCOVA, with age as a covariate revealed no interaction effect (Wilk’s = .99, F (4, 481) = 1.46, p > .05), but both main effects were significant (gender Wilk’s = .93, F (4, 481) = 8.62, p < .001, role Wilk’s = .956, F (4, 481) = 5.56, p < .001). Further analysis confirmed that athletes rated each of the four sub-scales as significantly more appropriate than coaches. Females rated social enquiries and invasion of personal space as more appropriate than males
Security and Efficiency Analysis of the Hamming Distance Computation Protocol Based on Oblivious Transfer
open access articleBringer et al. proposed two cryptographic protocols for the computation of Hamming distance. Their first scheme uses Oblivious Transfer and provides security in the semi-honest model. The other scheme uses Committed Oblivious Transfer and is claimed to provide full security in the malicious case. The proposed protocols have direct implications to biometric authentication schemes between a prover and a verifier where the verifier has biometric data of the users in plain form.
In this paper, we show that their protocol is not actually fully secure against malicious adversaries. More precisely, our attack breaks the soundness property of their protocol where a malicious user can compute a Hamming distance which is different from the actual value. For biometric authentication systems, this attack allows a malicious adversary to pass the authentication without knowledge of the honest user's input with at most complexity instead of , where is the input length. We propose an enhanced version of their protocol where this attack is eliminated. The security of our modified protocol is proven using the simulation-based paradigm. Furthermore, as for efficiency concerns, the modified protocol utilizes Verifiable Oblivious Transfer which does not require the commitments to outputs which improves its efficiency significantly
Flexible Automatic Scheduling For Autonomous Telescopes: The MAJORDOME
We have developped a new method for the scheduling of astronomical automatic
telescopes, in the framework of the autonomous TAROT instrument. The MAJORDOME
software can handle a variety of observations, constrained, periodic, etc., and
produces a timeline for the night, which may be modified at any time to take
into account the specific conditions of the night. The MAJORDOME can also
handle target of opportunity observations without delay.Comment: 16 pages, 6 figures, to appear in Experimental Astronom
Online media attribution of pipeline infrastructure failure, sourcing and the public health model: a content analysis of news stories on water and wastewater pipeline failures
Title from PDF of title page (University of Missouri--Columbia, viewed on May 26, 2011).The entire thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file; a non-technical public abstract appears in the public.pdf file.Thesis advisor: Dr. Shelly Rodgers.Includes bibliographical references.M.A. University of Missouri--Columbia 2011.The following study is a content analysis on how online media covers pipeline failure in North America. It uses the Public Health Model of Reporting, Sourcing and Attribution Theory to answer questions related to the cause and consequences of pipeline failure. The content analysis looked at 112 articles from 2010 highlighting events and issues related to pipeline and infrastructure failure such as sewer collapses, water main breaks and sinkholes. The articles were coded for frequency of the various failures, consequences and causes. The story type and sources of all articles were also coded to determine if there were any relationships between the variables. Additional information was gathered relating to other criteria specific to online articles, such as the availability of photos and video and social media feedback
Optimal Iris Fuzzy Sketches
Fuzzy sketches, introduced as a link between biometry and cryptography, are a
way of handling biometric data matching as an error correction issue. We focus
here on iris biometrics and look for the best error-correcting code in that
respect. We show that two-dimensional iterative min-sum decoding leads to
results near the theoretical limits. In particular, we experiment our
techniques on the Iris Challenge Evaluation (ICE) database and validate our
findings.Comment: 9 pages. Submitted to the IEEE Conference on Biometrics: Theory,
Applications and Systems, 2007 Washington D
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