2,353 research outputs found
Developing indicators to measure Technology Institutes` performance
Technology institutes (TIs) are non-profit innovation
and technology organisations aimed to
encourage competitiveness of firms. They are a
key organisation in the Spanish National Innovation
System because of their size and closeness
to the productive sector. Despite this, there is a
lack of studies trying to measure their performance
and its determinants. This work sheds some
light on this. We study the influence of operative,
financial, organisational, relational and general
variables on three measures of results: selffinance, impact and added value. Our conclusions show the relevance of this approach and are confirmed by grouping TIs according to their service supply characteristics.Publicad
Developing indicators to measure Technology Institutes` performance.
Technology institutes (TIs) are non-profit innovation and technology organisations aimed to encourage competitiveness of firms. They are a key organisation in the Spanish National Innovation System because of their size and closeness to the productive sector. Despite this, there is a lack of studies trying to measure their performance and its determinants. This work sheds some light on this. We study the influence of operative, financial, organisational, relational and general variables on three measures of results: selffinance, impact and added value. Our conclusions show the relevance of this approach and are confirmed by grouping TIs according to their service supply characteristics.
Baroclinic Vorticity Production in Protoplanetary Disks; Part I: Vortex Formation
The formation of vortices in protoplanetary disks is explored via
pseudo-spectral numerical simulations of an anelastic-gas model. This model is
a coupled set of equations for vorticity and temperature in two dimensions
which includes baroclinic vorticity production and radiative cooling. Vortex
formation is unambiguously shown to be caused by baroclinicity because (1)
these simulations have zero initial perturbation vorticity and a nonzero
initial temperature distribution; and (2) turning off the baroclinic term halts
vortex formation, as shown by an immediate drop in kinetic energy and
vorticity. Vortex strength increases with: larger background temperature
gradients; warmer background temperatures; larger initial temperature
perturbations; higher Reynolds number; and higher resolution. In the
simulations presented here vortices form when the background temperatures are
and vary radially as , the initial vorticity
perturbations are zero, the initial temperature perturbations are 5% of the
background, and the Reynolds number is . A sensitivity study consisting
of 74 simulations showed that as resolution and Reynolds number increase,
vortices can form with smaller initial temperature perturbations, lower
background temperatures, and smaller background temperature gradients. For the
parameter ranges of these simulations, the disk is shown to be convectively
stable by the Solberg-H{\o}iland criteria.Comment: Originally submitted to The Astrophysical Journal April 3, 2006;
resubmitted November 3, 2006; accepted Dec 5, 200
CoRoT's first seven planets: An overview
The up to 150 day uninterrupted high-precision photometry of about 100000
stars - provided so far by the exoplanet channel of the CoRoT space telescope -
gave a new perspective on the planet population of our galactic neighbourhood.
The seven planets with very accurate parameters widen the range of known planet
properties in almost any respect. Giant planets have been detected at low
metallicity, rapidly rotating and active, spotted stars. CoRoT-3 populated the
brown dwarf desert and closed the gap of measured physical properties between
standard giant planets and very low mass stars. CoRoT extended the known range
of planet masses down to 5 Earth masses and up to 21 Jupiter masses, the radii
to less than 2 Earth radii and up to the most inflated hot Jupiter found so
far, and the periods of planets discovered by transits to 9 days. Two CoRoT
planets have host stars with the lowest content of heavy elements known to show
a transit hinting towards a different planet-host-star-metallicity relation
then the one found by radial-velocity search programs. Finally the properties
of the CoRoT-7b prove that terrestrial planets with a density close to Earth
exist outside the Solar System. The detection of the secondary transit of
CoRoT-1 at the -level and the very clear detection of the 1.7 Earth
radii of CoRoT-7b at relative flux are promising evidence of
CoRoT being able to detect even smaller, Earth sized planets.Comment: 8 pages, 19 figures and 3 table
A Conley index study of the evolution of the Lorenz strange set
In this paper we study the Lorenz equations using the perspective of the
Conley index theory. More specifically, we examine the evolution of the strange
set that these equations posses throughout the different values of the
parameter. We also analyze some natural Morse decompositions of the global
attractor of the system and the role of the strange set in these
decompositions. We calculate the corresponding Morse equations and study their
change along the successive bifurcations. In addition, we formulate and prove
some theorems which are applicable in more general situations. These theorems
refer to Poincar\'{e}-Andronov-Hopf bifurcations of arbitrary codimension,
bifurcations with two homoclinic loops and a study of the role of the
travelling repellers in the transformation of repeller-attractor pairs into
attractor-repeller ones.Comment: 22 pages, 1 figur
Shape index, Brouwer degree and Poincaré-Hopf theorem
In this paper we study the relationship of the Brouwer degree of a vector field with the dynamics of the induced flow. Analogous relations are studied for the index of a vector field. We obtain new forms of the PoincarĂ©-Hopf theorem and of the Borsuk and Hirsch antipodal theorems. As an application, we calculate the Brouwer degree of the vector field of the Lorenz equations in isolating blocks of the Lorenz strange set.Depto. de Ălgebra, GeometrĂa y TopologĂaFac. de Ciencias MatemĂĄticasFALSEMinisterio de Ciencia, InnovaciĂłn y Universidadesunpu
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