129,414 research outputs found

    Web-based information systems development and dynamic organisational change: the need for emergent development tools

    Get PDF
    This paper considers contextual issues relating to the problem of developing web-based information systems in and for emergent organisations. It postulates that the methods available suffer because of sudden and unexpected changing characteristics within the organisation. The Theory of Deferred Action is used as the basis for the development of an emergent development tool. Many tools for managing change in a continuously changing organisation are susceptible to inadequacy. The insights proposed are believed to assist designers in developing functional and relevant approaches within dynamic organisational contexts

    Revisiting lepton flavor violation in supersymmetric type II seesaw

    Full text link
    In view of the recent measurement of reactor mixing angle θ13\theta_{13} and updated limit on BR(μeγ)BR(\mu \to e \gamma) by the MEG experiment, we re-examine the charged lepton flavor violations in a framework of supersymmetric type II seesaw mechanism. Supersymmetric type II seesaw predicts strong correlation between BR(μeγ)BR(\mu \to e \gamma) and BR(τμγ)BR(\tau \to \mu \gamma) mainly in terms of the neutrino mixing angles. We show that such a correlation can be determined accurately after the measurement of θ13\theta_{13}. We compute different factors which can affect this correlation and show that the mSUGRA-like scenarios, in which slepton masses are taken to be universal at the high scale, predicts 3.5BR(τμγ)/BR(μeγ)303.5 \lesssim BR(\tau \to \mu \gamma)/BR(\mu \to e \gamma) \lesssim 30 for normal hierarchical neutrino masses. Any experimental indication of deviation from this prediction would rule out the minimal models of supersymmetric type II seesaw. We show that the current MEG limit puts severe constraints on the light sparticle spectrum in mSUGRA model if the seesaw scale lies within 101310^{13}-101510^{15} GeV. It is shown that these constraints can be relaxed and relatively light sparticle spectrum can be obtained in a class of models in which the soft mass of triplet scalar is taken to be non-universal at the high scale.Comment: Minor changes in text; accepted for publication in Phys. Rev.

    C2AE: Class Conditioned Auto-Encoder for Open-set Recognition

    Full text link
    Models trained for classification often assume that all testing classes are known while training. As a result, when presented with an unknown class during testing, such closed-set assumption forces the model to classify it as one of the known classes. However, in a real world scenario, classification models are likely to encounter such examples. Hence, identifying those examples as unknown becomes critical to model performance. A potential solution to overcome this problem lies in a class of learning problems known as open-set recognition. It refers to the problem of identifying the unknown classes during testing, while maintaining performance on the known classes. In this paper, we propose an open-set recognition algorithm using class conditioned auto-encoders with novel training and testing methodology. In contrast to previous methods, training procedure is divided in two sub-tasks, 1. closed-set classification and, 2. open-set identification (i.e. identifying a class as known or unknown). Encoder learns the first task following the closed-set classification training pipeline, whereas decoder learns the second task by reconstructing conditioned on class identity. Furthermore, we model reconstruction errors using the Extreme Value Theory of statistical modeling to find the threshold for identifying known/unknown class samples. Experiments performed on multiple image classification datasets show proposed method performs significantly better than state of the art.Comment: CVPR2019 (Oral

    Flavour physics without flavour symmetries

    Full text link
    We quantitatively analyze a quark-lepton flavour model derived from a six-dimensional supersymmetric theory with SO(10)×U(1)SO(10)\times U(1) gauge symmetry, compactified on an orbifold with magnetic flux. Two bulk 16\mathbf{16}-plets charged under the U(1)U(1) provide the three quark-lepton generations whereas two uncharged 10\mathbf{10}-plets yield two Higgs doublets. At the orbifold fixed points mass matrices are generated with rank one or two. Moreover, the zero modes mix with heavy vectorlike split multiplets. The model possesses no flavour symmetries. Nevertheless, there exist a number of relations between Yukawa couplings, remnants of the underlying GUT symmetry and the wave function profiles of the zero modes, which lead to a prediction of the light neutrino mass scale, mν1103m_{\nu_1} \sim 10^{-3} eV and heavy Majorana neutrino masses in the range from 101210^{12} GeV to 101410^{14} GeV. The model successfully includes thermal leptogenesis.Comment: Minor additions; Published versio

    Yukawa coupling unification in SO(10) with positive \mu\ and a heavier gluino

    Full text link
    The t-b-tau unification with positive Higgs mass parameter \mu\ in the minimal supersymmetric standard model prefers "just so" Higgs splitting and a light gluino < 500 GeV which appears to be ruled out by the recent LHC searches. We reanalyze constraints on soft supersymmetry breaking parameters in this scenario allowing independent splittings among squarks and Higgs doublets at the grand unification scale and show that it is possible to obtain t-b-tau unification and satisfy experimental constraints on gluino mass without raising supersymmetry breaking scale to very high value ~ 20 TeV. We discuss the origin of independent squark and Higgs splittings in realistic SO(10) models. Just so Higgs splitting can be induced without significantly affecting the t-b-tau unification in SO(10) models containing Higgs fields transforming as 10+\bar{126}+126+210. This splitting arises in the presence of non-universal boundary conditions from mixing between 10 and other Higgs fields. Similarly, if additional matter fields are introduced then their mixing with the matter multiplet 16 is shown to generate the squark splitting required to raise the gluino mass within the t-b-tau unified models with positive \mu.Comment: 19 pages, 6 figure
    corecore