4,115 research outputs found

    Using a Bayesian averaging model for estimating the reliability of decisions in multimodal biometrics

    Get PDF
    The issue of reliable authentication is of increasing importance in modern society. Corporations, businesses and individuals often wish to restrict access to logical or physical resources to those with relevant privileges. A popular method for authentication is the use of biometric data, but the uncertainty that arises due to the lack of uniqueness in biometrics has lead there to be a great deal of effort invested into multimodal biometrics. These multimodal biometric systems can give rise to large, distributed data sets that are used to decide the authenticity of a user. Bayesian model averaging (BMA) methodology has been used to allow experts to evaluate the reliability of decisions made in data mining applications. The use of decision tree (DT) models within the BMA methodology gives experts additional information on how decisions are made. In this paper we discuss how DT models within the BMA methodology can be used for authentication in multimodal biometric systems

    Microwave properties of (PrxY1−x)Ba2Cu3O7−δ(Pr_xY_{1-x})Ba_2Cu_3O_{7-\delta} : Influence of magnetic scattering

    Full text link
    We report measurements of the surface impedance Zs=Rs+iXsZ_s=R_s+iX_s of (PrxY1−x)Ba2Cu3O7−δ(Pr_xY_{1-x})Ba_2Cu_3O_{7-\delta}, (x=0,0.15,0.23,0.3,0.4,0.5)(x=0,0.15,0.23,0.3,0.4,0.5). Increasing PrPr concentration leads to some striking results not observed in samples doped by non-magnetic constituents. The three principal features of the Rs(T)R_s(T) data - multiple structure in the transition, a high residual resistance and, at high PrPr concentrations, an upturn of the low TT data, are all characteristic of the influence of magnetic scattering on superconductivity, and appear to be common to materials where magnetism and superconductivity coexist. The low TT behavior of λ(T)\lambda (T) appears to change from TT to T4T^4 at large PrPr doping, and provides evidence of the influence of magnetic pairbreaking of the PrPr.Comment: 5 pages, 3 eps figures, Revtex, 2-column format, uses graphicx. To appear in Physica C. Postscript version also available at http://sagar.physics.neu.edu/preprints.htm

    India Giving: Insights into the Nature of Giving Across India

    Get PDF
    Giving in India is as ancient as the country itself. The instinct to give is part of the ebb and flow of our daily lives, permeating our religions, our culture and our history. Looking to the future, my firm belief is that philanthropy in India is destined to soar over the next decade. I believe this for two key reasons. The first is the sheer depth of social need in India. While the future promises much, the reality today remains that tens of millions across India need food, shelter and medicine on a daily basis. We know from India's 2011 census that by the time children being born today are teenagers, India will likely be the most populous nation in the world. For this growth to be sustainable, the change that philanthropy can bring will be vital. The second reason is the groundswell of evidence. A belief that philanthropy is on the rise in India is widely held, yet in truth, not enough is known about the size, scope, and impact of our generosity. Though there have been a few attempts to research and quantify individual giving, most of these studies have focussed on 'High Net Worth Individuals', rather than the general public. In order to nurture and expand charitable giving effectively, we must work with evidence that describes the broad context, such as the burgeoning middle class. With a reliable view of the dynamics of individual giving across the different socio-economic settings, we will be able to unlock knowledge that will encourage those who can afford to give, to give as much as they can

    UK security breach investigations report: an analysis of data compromise cases

    Get PDF
    This report, rather than relying on questionnaires and self-reporting, concerns cases that were investigated by the forensic investigation team at 7Safe. Whilst removing any inaccuracies arising from self-reporting, the authors acknowledge that the limitation of the sample size remains. It is hoped that the unbiased reporting by independent investigators has yielded interesting facts about modern security breaches. All data in this study is based on genuine completed breach investigations conducted by the compromise investigation team over the last 18 months

    SDL: A Surface Description Language

    Get PDF
    A new interpreted language specifically designed for surface grid generation is introduced. Many unique aspects of the language are discussed, including the farray, vector, curve, and surface data types and the operators used to manipulate them. Custom subroutine libraries written in the language are used to easily build surface grids for generic missile shapes

    CCBS – a method to maintain memorability, accuracy of password submission and the effective password space in click-based visual passwords

    Get PDF
    Text passwords are vulnerable to many security attacks due to a number of reasons such as the insecure practices of end users who select weak passwords to maintain their long term memory. As such, visual password (VP) solutions were developed to maintain the security and usability of user authentication in collaborative systems. This paper focuses on the challenges facing click-based visual password systems and proposes a novel method in response to them. For instance, Hotspots reveal a serious vulnerability. They occur because users are attracted to specific parts of an image and neglect other areas. Undertaking image analysis to identify these high probability areas can assist dictionary attacks. Another concern is that click-based systems do not guide users towards the correct click-point they are aiming to select. For instance, users might recall the correct spot or area but still fail to include their click within the tolerance distance around the original click-point which results in more incorrect password submissions. Nevertheless, the Passpoints study by Wiedenbeck et al., 2005 inspected the retention of their VP in comparison with text passwords over the long term. Despite being cued-recall the successful rate of their VP submission was not superior to text passwords as it decreased from 85% (the instant retention on the day of registration) to 55% after 2 weeks. This result was identical to that of the text password in the same experiment. The successful submission rates after 6 weeks were also 55% for both VP and text passwords. This paper addresses these issues, and then presents a novel method (CCBS) as a usable solution supported by an empirical proof. A user study is conducted and the results are evaluated against a comparative study

    Heavy fermion superconductivity in the filled skutterudite compound PrOs4_4Sb12_{12}

    Full text link
    The filled skutterudite compound \PrOsSb{} has been found to exhibit superconductivity with a critical temperature Tc=1.85T_\mathrm{c} = 1.85 K that develops out of a heavy Fermi liquid with an effective mass m∗≈50mem^{*} \approx 50 m_\mathrm{e}. The current experimental situation regarding the heavy fermion state, the superconducting state, and a high field, low temperature phase that is apparently associated with magnetic or quadrupolar order in \PrOsSb{} is briefly reviewed herein.Comment: 4 pages, 2 figures, presented at the LT23 23rd International Conference on Low Temperature Physics, Hiroshima, Japa

    Cyberstalking in the United Kingdom: an analysis of the ECHO Pilot Survey

    Get PDF
    An Analysis of the ECHO Pilot SurveyNetwork for Surviving Stalking is internationally recognised as the leading Registered Charity in the United Kingdom dedicated to supporting victims of stalking, free of cost or commercial gain. It aims to provide support to victims, potential victims and others affected by stalking or harassment throughout the UK, to raise awareness of the subject and to provide information about stalking and harassment to professionals, relevant agencies and the public. As we have moved into an age of electronic information and communication, stalkers have found new, more effective and efficient means to perpetrate their malicious acts; stalkers have become Cyberstalkers. Cyberstalking has become somewhat of an epidemic stretching across the globe. Network for Surviving Stalking began to notice that an increasing number of people searching for support were being stalked or harassed online, making the charity concerned as to the prevalence, nature and impact of cyberstalking. The charity commissioned a team of researchers and together developed an online questionnaire to establish answers to these questions. This report provides an analysis of the responses to the questionnaire
    • …
    corecore