227 research outputs found
Cosmology with Gamma-Ray Bursts Using k-correction
In the case of Gamma-Ray Bursts with measured redshift, we can calculate the
k-correction to get the fluence and energy that were actually produced in the
comoving system of the GRB. To achieve this we have to use well-fitted
parameters of a GRB spectrum, available in the GCN database. The output of the
calculations is the comoving isotropic energy E_iso, but this is not the
endpoint: this data can be useful for estimating the {\Omega}M parameter of the
Universe and for making a GRB Hubble diagram using Amati's relation.Comment: 4 pages, 6 figures. Presented as a talk on the conference '7th
INTEGRAL/BART Workshop 14 -18 April 2010, Karlovy Vary, Czech Republic'.
Published in Acta Polytechnic
Designing Traceability into Big Data Systems
Providing an appropriate level of accessibility and traceability to data or
process elements (so-called Items) in large volumes of data, often
Cloud-resident, is an essential requirement in the Big Data era.
Enterprise-wide data systems need to be designed from the outset to support
usage of such Items across the spectrum of business use rather than from any
specific application view. The design philosophy advocated in this paper is to
drive the design process using a so-called description-driven approach which
enriches models with meta-data and description and focuses the design process
on Item re-use, thereby promoting traceability. Details are given of the
description-driven design of big data systems at CERN, in health informatics
and in business process management. Evidence is presented that the approach
leads to design simplicity and consequent ease of management thanks to loose
typing and the adoption of a unified approach to Item management and usage.Comment: 10 pages; 6 figures in Proceedings of the 5th Annual International
Conference on ICT: Big Data, Cloud and Security (ICT-BDCS 2015), Singapore
July 2015. arXiv admin note: text overlap with arXiv:1402.5764,
arXiv:1402.575
Flat band ferromagnetism without connectivity conditions in the flat band
It is known that a system which exhibits a half filled lowest flat band and
the localized one-particle Wannier states on the flat band satisfy the
connectivity conditions, is always ferromagnetic. Without the connectivity
conditions on the flat band, the system is non-magnetic. We show that this is
not always true. The reason is connected to a peculiar behavior of the band
situated just above the flat band.Comment: 15 pages, 4 figure
Querying Large Physics Data Sets Over an Information Grid
Optimising use of the Web (WWW) for LHC data analysis is a complex problem
and illustrates the challenges arising from the integration of and computation
across massive amounts of information distributed worldwide. Finding the right
piece of information can, at times, be extremely time-consuming, if not
impossible. So-called Grids have been proposed to facilitate LHC computing and
many groups have embarked on studies of data replication, data migration and
networking philosophies. Other aspects such as the role of 'middleware' for
Grids are emerging as requiring research. This paper positions the need for
appropriate middleware that enables users to resolve physics queries across
massive data sets. It identifies the role of meta-data for query resolution and
the importance of Information Grids for high-energy physics analysis rather
than just Computational or Data Grids. This paper identifies software that is
being implemented at CERN to enable the querying of very large collaborating
HEP data-sets, initially being employed for the construction of CMS detectors.Comment: 4 pages, 3 figure
Effects of (axial)vector mesons on the chiral phase transition: initial results
We investigate the effects of (axial)vector mesons on the chiral phase
transition in the framework of an SU(3), (axial)vector meson extended linear
sigma model with additional constituent quarks and Polyakov loops. We determine
the parameters of the Lagrangian at zero temperature in a hybrid approach,
where we treat the mesons at tree-level, while the constituent quarks at 1-loop
level. We assume two nonzero scalar condensates and together with the
Polyakov-loop variables we determine their temperature dependence according to
the 1-loop level field equations.Comment: 4 pages, 2 figures, MESON2014 - the 13^{th} International Workshop on
Meson Production, Properties and Interactio
Pattern Reification as the Basis for Description-Driven Systems
One of the main factors driving object-oriented software development for
information systems is the requirement for systems to be tolerant to change. To
address this issue in designing systems, this paper proposes a pattern-based,
object-oriented, description-driven system (DDS) architecture as an extension
to the standard UML four-layer meta-model. A DDS architecture is proposed in
which aspects of both static and dynamic systems behavior can be captured via
descriptive models and meta-models. The proposed architecture embodies four
main elements - firstly, the adoption of a multi-layered meta-modeling
architecture and reflective meta-level architecture, secondly the
identification of four data modeling relationships that can be made explicit
such that they can be modified dynamically, thirdly the identification of five
design patterns which have emerged from practice and have proved essential in
providing reusable building blocks for data management, and fourthly the
encoding of the structural properties of the five design patterns by means of
one fundamental pattern, the Graph pattern. A practical example of this
philosophy, the CRISTAL project, is used to demonstrate the use of
description-driven data objects to handle system evolution.Comment: 20 pages, 10 figure
Product Development from Veneer-Mill Residues: An Application of the Taguchi's Method
The raw material used for decorative (face) veneer manufacturing consists mainly of hardwood logs, the highest in quality harvested for industrial purposes. Besides the common sawmill residuals, the clipping operation in the process produces quite long, strand-type vestiges, and large end-clipping cutoffs. During the course of the research project presented in this article, structural composite materials were designed and formulated using these clipping residues as principal furnish materials. A robust statistical product development technique, the Taguchi's method, helped to identify the effect of component factors on the expected mechanical properties of these novel products.Results of three-factor/three-level analyses indicated that there is a linear positive correlation between target density and performance attributes (MOE and MOR). Increasing the content of end-clippings up to 25% resulted in decline of strength and stiffness. However, when the ratio was over 1 to 4, this trend proved to be negligible. Resin solid content within the selected range had no significant control over the examined panel properties
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