55,399 research outputs found
One-loop calculations in Supersymmetric Lattice QCD
We study the self energies of all particles which appear in a lattice
regularization of supersymmetric QCD (). We compute, perturbatively
to one-loop, the relevant two-point Green's functions using both the
dimensional and the lattice regularizations. Our lattice formulation employs
the Wilson fermion acrion for the gluino and quark fields. The gauge group that
we consider is while the number of colors, and the number of
flavors, , are kept as generic parameters. We have also searched for
relations among the propagators which are computed from our one-loop results.
We have obtained analytic expressions for the renormalization functions of the
quark field (), gluon field (), gluino field () and
squark field ().
We present here results from dimensional regularization, relegating to a
forthcoming publication our results along with a more complete list of
references. Part of the lattice study regards also the renormalization of quark
bilinear operators which, unlike the non-supersymmetric case, exhibit a rich
pattern of operator mixing at the quantum level.Comment: 6 pages, 5 figure, XII Quark Confinement proceeding
Structural vulnerability of Nepalese Pagoda temples
Nepal is located in one of the most severe earthquake prone areas of the world, lying between collisions of Indian to the Eurasian plate, moving continuously, resulting in frequent devastating earthquakes within this region. Moreover, different authors refer mention that the accumulated slip deficit (central seismic gap) is likely to produce large earthquakes in the future. Also, the analysis of the available information of previous earthquakes indicates the potential damage that can occurs in unreinforced traditional masonry structures in future earthquakes.
Most of the Nepalese pagoda temples were erected following very simple rules and construction details to accomplish with seismic resistance requirement, or even without any consideration for seismic resistance, during the period of Malla dynasty (1200-1768). Presently, conservation and restoration of ancient monuments are one of the major concerns in order to preserve our built heritage, transferring it to the future generations. The present paper is devoted to outline particular structural fragility characteristics in the historic Nepalese pagoda temples which affect their seismic performance. Moreover, based on the parametric analysis identified structural weaknesses/fragilities of pagoda topology, the associated traditional building technology and constructional details
Stochastic blockmodel approximation of a graphon: Theory and consistent estimation
Non-parametric approaches for analyzing network data based on exchangeable
graph models (ExGM) have recently gained interest. The key object that defines
an ExGM is often referred to as a graphon. This non-parametric perspective on
network modeling poses challenging questions on how to make inference on the
graphon underlying observed network data. In this paper, we propose a
computationally efficient procedure to estimate a graphon from a set of
observed networks generated from it. This procedure is based on a stochastic
blockmodel approximation (SBA) of the graphon. We show that, by approximating
the graphon with a stochastic block model, the graphon can be consistently
estimated, that is, the estimation error vanishes as the size of the graph
approaches infinity.Comment: 20 pages, 4 figures, 2 algorithms. Neural Information Processing
Systems (NIPS), 201
On the Evaluation of the Mechanical Behaviour of Structural Glass Elements
Glass can be considered to be a high-technology engineering material with a
multifunctional potential for structural applications. However, the conventional approach to the use
of glass is often based only on its properties of transparency and isolation. It is thus highly
appropriate and necessary to study the mechanical behaviour of this material and to develop
adequate methods and models leading to its characterisation. It is evident that the great potential of
growth for structural glass applications is an important opportunity of development for the glass
industry and the building/construction sectors. The work presented in this paper is a reflection of
this conclusion. The authors shortly present the state-of-the-art on the application of glass as a
structural element in building and construction, and refer to other potential fields of application and
available glass materials. The experimental procedures and methods adopted in three-point bending
tests performed on 500 × 100 [mm2] float, laminated and tempered glass specimens with
thicknesses between 4 and 19 mm are thoroughly described. The authors evaluated the mechanical
strength and stiffness of glass for structural applications. This work contributes to a deeper
knowledge of the properties of this material
The matching method for treatment evaluation with selective participation and inelligibles
The matching method for treatment evaluation does not balance selective unobserved differences between treated and non-treated. We derive a simple correction term if there is an instrument that shifts the treatment probability to zero in specific cases. Policies with eligibility restrictions,
where treatment is impossible if some variable exceeds a certain value, provide a natural application. In an empirical analysis, we first examine the performance of matching versus regression-discontinuity estimation in the
sharp age-discontinuity design of the NDYP job search assistance program for young unemployed in the UK. Next, we exploit the age eligibility restriction in the Swedish Youth Practice subsidized work program for young unemployed, where compliance is imperfect among the young. Adjusting
the matching estimator for selectivity changes the results towards ineffectiveness of subsidized work in moving individuals into employment
Perturbatively improving renormalization constants
Renormalization factors relate the observables obtained on the lattice to
their measured counterparts in the continuum in a suitable renormalization
scheme. They have to be computed very precisely which requires a careful
treatment of lattice artifacts. In this work we present a method to suppress
these artifacts by subtracting one-loop contributions proportional to the
square of the lattice spacing calculated in lattice perturbation theory.Comment: 7 pages, 2 figures, LATTICE 201
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