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Generalised additive dependency inflated models including aggregated covariates
Let us assume that X, Y and U are observed and that the conditional mean of U given X and Y can be expressed via an additive dependency of X, λ(X)Y and X + Y for some unspecified function . This structured regression model can be transferred to a hazard model or a density model when applied on some appropriate grid, and has important forecasting applications via structured marker dependent hazards models or structured density models including age-period-cohort relationships. The structured regression model is also important when the severity of the dependent variable has a complicated dependency on waiting times X, Y and the total waiting time X+Y . In case the conditional mean of U approximates a density, the regression model can be used to analyse the age-period-cohort model, also when exposure data are not available. In case the conditional mean of U approximates a marker dependent hazard, the regression model introduces new relevant age-period-cohort time scale interdependencies in understanding longevity. A direct use of the regression relationship introduced in this paper is the estimation of the severity of outstanding liabilities in non-life insurance companies. The technical approach taken is to use B-splines to capture the underlying one-dimensional unspecified functions. It is shown via finite sample simulation studies and an application for forecasting future asbestos related deaths in the UK that the B-spline approach works well in practice. Special consideration has been given to ensure identifiability of all models considered
Study of Strangeness Condensation by Expanding About the Fixed Point of the Harada-Yamawaki Vector Manifestation
Building on, and extending, the result of a higher-order in-medium chiral
perturbation theory combined with renormalization group arguments and a variety
of observations of the vector manifestation of Harada-Yamawaki hidden local
symmetry theory, we obtain a surprisingly simple description of kaon
condensation by fluctuating around the "vector manifestation (VM)" fixed point
identified to be the chiral restoration point. Our development establishes that
strangeness condensation takes place at about 3 n_0 where n_0 is nuclear matter
density. This result depends only on the renoramlization-group (RG) behavior of
the vector interactions, other effects involved in fluctuating about the bare
vacuum in so many previous calculations being "irrelevant" in the RG about the
fixed point. Our results have major effects on the collapse of neutron stars
into black holes.Comment: 4 page
Dilatons for Dense Hadronic Matter
The idea that the explicit breaking of scale invariance by the trace anomaly
of QCD can be rephrased as a spontaneous breaking has been recently exploited
to capture the low-energy strong interaction dynamics of dense (and also hot)
matter in terms of two dilaton fields, the "soft" (chi_s) and the "hard"
(chi_h) fields, in the frame work of the hidden local gauge symmetry. In the
Freund-Nambu model, the spontaneous symmetry breaking of scale symmetry is
induced by an explicitly breaking term, while the spontaneous symmetry breaking
is possible in the flat potential model which is scale symmetric. We discuss
the interplay of the soft and hard dilatons using the spontaneously broken
scale symmetry schemes and uncover a novel structure of dense matter hitherto
unexplored.Comment: 7 pages, Invited talks presented at 4th International Conference on
Symmetres in Subatomic Physics, June 2-5, 2009, Taipei, Taiwa
A collective scattering system for measuring electron gyroscale fluctuations on the National Spherical Torus Experiment
A collective scattering system has been installed on the National Spherical Torus Experiment (NSTX) to measure electron gyroscale fluctuations in NSTX plasmas. The system measures fluctuations with k(perpendicular to)rho(e)less than or similar to 0.6 and k(perpendicular to)less than or similar to 20 cm(-1). Up to five distinct wavenumbers are measured simultaneously, and the large toroidal curvature of NSTX plasmas provides enhanced spatial localization. Steerable optics can position the scattering volume throughout the plasma from the magnetic axis to the outboard edge. Initial measurements indicate rich turbulent dynamics on the electron gyroscale. The system will be a valuable tool for investigating the connection between electron temperature gradient turbulence and electron thermal transport in NSTX plasmas.X1137sciescopu
Presure-Induced Superconducting State of Antiferromagnetic CaFeAs
The antiferromagnet CaFeAs does not become superconducting when
subject to ideal hydrostatic pressure conditions, where crystallographic and
magnetic states also are well defined. By measuring electrical resistivity and
magnetic susceptibility under quasi-hydrostatic pressure, however, we find that
a substantial volume fraction of the sample is superconducting in a narrow
pressure range where collapsed tetragonal and orthorhombic structures coexist.
At higher pressures, the collapsed tetragonal structure is stabilized, with the
boundary between this structure and the phase of coexisting structures strongly
dependent on pressure history. Fluctuations in magnetic degrees of freedom in
the phase of coexisting structures appear to be important for
superconductivity.Comment: revised (6 pages, 5 figures) - includes additional experimental
result
Influences of an impurity on the transport properties of one-dimensional antisymmetric spin filter
The influences of an impurity on the spin and the charge transport of
one-dimensional antisymmetric spin filter are investigated using bosonization
and Keldysh formulation and the results are highlighted against those of
spinful Luttinger liquids. Due to the dependence of the electron spin
orientation on wave number the spin transport is not affected by the impurity,
while the charge transport is essentially identical with that of spinless
one-dimensional Luttinger liquid.Comment: 7 pages, 2 figures. To appear in Physical Review
Automatic Dimension Selection for a Non-negative Factorization Approach to Clustering Multiple Random Graphs
We consider a problem of grouping multiple graphs into several clusters using
singular value thesholding and non-negative factorization. We derive a model
selection information criterion to estimate the number of clusters. We
demonstrate our approach using "Swimmer data set" as well as simulated data
set, and compare its performance with two standard clustering algorithms.Comment: This paper has been withdrawn by the author due to a newer version
with overlapping content
Holographic Meson Spectra in the Dense Medium with Chiral Condensate
We study two effects on the meson spectra by using the AdS/CFT
correspondence where the corrections from the chiral condensate and the
quark density are controlled by the gravitational backreaction of the massive
scalar field and U(1) gauge field respectively. The dual geometries with zero
and nonzero current quark masses are obtained numerically. We discuss meson
spectra and binding energy of heavy quarkonium with the subleading corrections
in the hard wall model.Comment: 16 pages, 4 figure
Balancing the power of multimedia information retrieval and usability in designing interactive TV
Steady progress in the field of multimedia information retrieval (MMIR) promises a useful set of tools that could provide new usage scenarios and features to enhance the user experience in today s digital media applications. In the interactive TV domain, the simplicity of interaction is more crucial than in any other digital media domain and ultimately determines the success or otherwise of any new applications. Thus when integrating emerging tools like MMIR into interactive TV, the increase in interface complexity and sophistication resulting from these features can easily reduce its actual usability. In this paper we describe a design strategy we developed as a result of our e®ort in balancing the power of emerging multimedia information retrieval techniques and maintaining the simplicity of the interface in interactive TV. By providing multiple levels of interface sophistication in increasing order as a viewer repeatedly presses the same button on their remote control, we provide a layered interface that can accommodate viewers requiring varying degrees of power and simplicity. A series of screen shots from the system we have actually developed and built illustrates how this is achieved
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