2,460 research outputs found
Approaches on investments in continuing management knowledge turnover apprising
This paper approaches the problem of knowledge accumulation by the management team of organizations, but specially that ones focused on obtaining profit in order to obtain competitive advantage. After a brief presentation of the general context, the idea of continuing learning as investment is developed, tacit and explicit knowledge are differentiated and a grouping of knowledge into standardized, specialized and created knowledge is proposed. Further is proposed a process of continuing learning process for management team and the stages of continuing learning. Finally, a model of appraising investments in management knowledge turnover is also proposed.learning; knowledge; investments in management knowledge; investments in knowledge turnover
Bisous model - detecting filamentary patterns in point processes
The cosmic web is a highly complex geometrical pattern, with galaxy clusters
at the intersection of filaments and filaments at the intersection of walls.
Identifying and describing the filamentary network is not a trivial task due to
the overwhelming complexity of the structure, its connectivity and the
intrinsic hierarchical nature. To detect and quantify galactic filaments we use
the Bisous model, which is a marked point process built to model
multi-dimensional patterns. The Bisous filament finder works directly with the
galaxy distribution data and the model intrinsically takes into account the
connectivity of the filamentary network. The Bisous model generates the visit
map (the probability to find a filament at a given point) together with the
filament orientation field. Using these two fields, we can extract filament
spines from the data. Together with this paper we publish the computer code for
the Bisous model that is made available in GitHub. The Bisous filament finder
has been successfully used in several cosmological applications and further
development of the model will allow to detect the filamentary network also in
photometric redshift surveys, using the full redshift posterior. We also want
to encourage the astro-statistical community to use the model and to connect it
with all other existing methods for filamentary pattern detection and
characterisation.Comment: 12 pages, 6 figures, accepted by Astronomy and Computin
Filaments in observed and mock galaxy catalogues
Context. The main feature of the spatial large-scale galaxy distribution is
an intricate network of galaxy filaments. Although many attempts have been made
to quantify this network, there is no unique and satisfactory recipe for that
yet. Aims. The present paper compares the filaments in the real data and in the
numerical models, to see if our best models reproduce statistically the
filamentary network of galaxies. Methods. We apply an object point process with
interactions (the Bisous process) to trace and describe the filamentary network
both in the observed samples (the 2dFGRS catalogue) and in the numerical models
that have been prepared to mimic the data.We compare the networks. Results. We
find that the properties of filaments in numerical models (mock samples) have a
large variance. A few mock samples display filaments that resemble the observed
filaments, but usually the model filaments are much shorter and do not form an
extended network. Conclusions. We conclude that although we can build numerical
models that are similar to observations in many respects, they may fail yet to
explain the filamentary structure seen in the data. The Bisous-built filaments
are a good test for such a structure.Comment: 13 pages, accepted for publication in Astronomy and Astrophysic
Pion mass effects on axion emission from neutron stars through NN bremsstrahlung processes
The rates of axion emission by nucleon-nucleon bremsstrahlung are calculated
with the inclusion of the full momentum contribution from a nuclear one pion
exchange (OPE) potential. The contributions of the neutron-neutron (nn),
proton-proton (pp) and neutron-proton (np) processes in both the nondegenerate
and degenerate limits are explicitly given. We find that the finite momentum
corrections to the emissivities are quantitatively significant for the
non-degenerate regime and temperature-dependent, and should affect the existing
axion mass bounds. The trend of these nuclear effects is to diminish the
emissivities
Kaluza-Klein relics from warped reheating
It has been suggested that after brane-antibrane inflation in a
Klebanov-Strassler (KS) warped throat, metastable Kaluza-Klein (KK) excitations
can be formed due to nearly-conserved angular momenta along isometric
directions in the throat. If sufficiently long-lived, these relics could
conflict with big bang nucleosynthesis or baryogenesis by dominating the energy
density of the universe. We make a detailed estimate of the decay rate of such
relics using the low energy effective action of type IIB string theory
compactified on the throat geometry, with attention to powers of the warp
factor. We find that it is necessary to turn on SUSY-breaking deformations of
the KS background in order to ensure that the most dangerous relics will decay
fast enough. The decay rate is found to be much larger than the naive guess
based on the dimension of the operators which break the angular isometries of
the throat. For an inflationary warp factor of order , we obtain
the bound M_{3/2} \gsim 10^9 GeV on the scale of SUSY breaking to avoid
cosmological problems from the relics, which is satisfied in the KKLT
construction assumed to stabilize the compactification. Given the requirement
that the relics decay before nucleosynthesis or baryogenesis, we place bounds
on the mass of the relic as a function of the warp factor in the throat for
more general warped backgrounds.Comment: 30 pages, 7 figures. Added analysis and discussions to address the
referees concerns: explored the effects of different IR boundary conditions,
clarified the role of the simplified toy model, discussed the dominant
SUSY-preserving decay route (but still conclude the SUSY-breaking one is
faster). All original conclusions still hol
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