102 research outputs found
Sustainable growth rate in the strategic analysis of brewery industry
An analysis of sustainable growth rate could considerably improve an assessment of Strategic Business Unit’s potential. The sustainable growth rate analysis enabled us to compare a possible growth rate within the brewery industry with a growth rate that firms had achieved. To demonstrate this in more depth, we presented a case study of the brewery industry in Poland and Czech Republic.Growth, strategic analysis, seer industry, corporate growth, Research and Development/Tech Change/Emerging Technologies, GA, IN,
A new method for the spectroscopic identification of stellar non-radial pulsation modes. I. The method and numerical tests
We present the Fourier parameter fit method, a new method for
spectroscopically identifying stellar radial and non-radial pulsation modes
based on the high-resolution time-series spectroscopy of absorption-line
profiles. In contrast to previous methods this one permits a quantification of
the statistical significance of the computed solutions. The application of
genetic algorithms in seeking solutions makes it possible to search through a
large parameter space. The mode identification is carried out by minimizing
chi-square, using the observed amplitude and phase across the line profile and
their modeled counterparts. Computations of the theoretical line profiles are
based on a stellar displacement field, which is described as superposition of
spherical harmonics and that includes the first order effects of the Coriolis
force. We made numerical tests of the method on a grid of different mono- and
multi-mode models for 0 <= l <= 4 in order to explore its capabilities and
limitations. Our results show that whereas the azimuthal order m can be
unambiguously identified for low-order modes, the error of l is in the range of
pm 1. The value of m can be determined with higher precision than with other
spectroscopic mode identification methods. Improved values for the inclination
can be obtained from the analysis of non-axisymmetric pulsation modes. The new
method is ideally suited to intermediatley rotating Delta Scuti and Beta Cephei
stars.Comment: 12 pages, 14 figure
The effects of moderately fast shellular rotation on adiabatic oscillations
We investigate adiabatic oscillations for delta Scuti star models, taking
into account a moderate rotation velocity ~100 \km/s. The resulting oscillation
frequencies include corrections for rotation up to second order in the rotation
rate including those of near degeneracy. Effects of either a uniform rotation
or a rotation profile assuming local angular momentum conservation of the form
Omega=Omega(r) on oscillation frequencies are compared. As expected, important
differences (around 3 microHz) are obtained in the and mixed mode regions.
For higher frequency p modes, differences range between 1 microHz and 3
microHz. Such differences are likely to be detectable with future space
missions such as COROT, where precisions in frequency around 0.5 microHz will
be reachable.Comment: A&A, in press (18 pag, 14 fig
Challenges for stellar pulsation and evolution theory
During the last few decades, great effort has been made towards understanding
hydrodynamical processes which determine the structure and evolution of stars.
Up to now, the most stringent constraints have been provided by helioseismology
and stellar cluster studies. However, the contribution of asteroseismology
becomes more and more important, giving us an opportunity to probe the
interiors and atmospheres of very different stellar objects. A variety of
pulsating variables allows us to test various parameters of micro- and
macrophysics by means of oscillation data. I will review the most outstanding
key problems, both observational and theoretical, of which our knowledge can be
improved by means of asteroseismology.Comment: Invited talk presented at the JENAM 2008 Symposium No.4
"Asteroseismology and stellar evolution", eds. S. Schuh and G. Handler.,
Communications in Asteroseismology, 159, in press; 11 pages, 1 figur
- …