4,663 research outputs found
Keynesian and schumpeterian efficiency in a BOP-constrained growth model
The paper aims to contribute to the debate on specialization and growth in two forms. Firstly, it develops a North-South model in which the ratio between the income elasticity of exports and imports in the South (that gives the rate of growth compatible with external equilibrium) depends on the Keynesian and Schumpeterian efficiency of the pattern of specialization, as defined by Dosi et al (1990). The model draws on key insights of the technology gap literature to discuss how these efficiencies are related to the dynamics of technological learning. Secondly, the model is tested including the variables Keynesian and Schumpeterian efficiency in a Keynesian growth regression. Several estimation procedures are used to test the model, among which Finite Mixture Estimation, which allows for estimating the parameters for homogenous groups of countries.Schumpeterian efficiency, keynesian efficiency, balance-of-payments-constrained growth, Thirlwall's Law
Confronting the models of 3:2 quasiperiodic oscillations with the rapid spin of the microquasar GRS 1915+105
Spectral fitting of the spin a in the microquasar GRS 1915+105 estimate
values higher than a=0.98. However, there are certain doubts about this
(nearly) extremal number. Confirming a high value of a>0.9 would have
significant concequences for the theory of high-frequency quasiperiodic
oscillations (HF QPOs). Here we discuss its possible implications assuming
several commonly used orbital models of 3:2 HF QPOs. We show that the estimate
of a>0.9 is almost inconsistent with two hot-spot (relativistic precession and
tidal disruption) models and the warped disc resonance model. In contrast, we
demonstrate that the epicyclic resonance and discoseismic models assuming the
c- and g- modes are favoured. We extend our discussion to another two
microquasars that display the 3:2 HF QPOs. The frequencies of these QPOs scale
roughly inversely to the microquasar masses, and the differences in the
individual spins, such as a=0.9 compared to a=0.7, represent a generic problem
for most of the discussed geodesic 3:2 QPO models. To explain the observations
of all the three microquasars by one unique mechanism, the models would have to
accommodate very large non-geodesic corrections.Comment: 7 pages, 3 figures, 2 tables; v2: corrections in the introduction,
language corrections (Astronomy & Astrophysics proof-readed version
Super-spinning compact objects and models of high-frequency quasi-periodic oscillations observed in Galactic microquasars. II. Forced resonances
In our previous work (Paper I) we applied several models of high-frequency
quasi-periodic oscillations (HF QPOs) to estimate the spin of the central
compact object in three Galactic microquasars assuming the possibility that the
central compact body is a super-spinning object (or a naked singularity) with
external spacetime described by Kerr geometry with a dimensionless spin
parameter . Here we extend our consideration, and in a
consistent way investigate implications of a set of ten resonance models so far
discussed only in the context of . The same physical arguments as in Paper
I are applied to these models, i.e. only a small deviation of the spin estimate
from , , is assumed for a favoured model. For five of these
models that involve Keplerian and radial epicyclic oscillations we find the
existence of a unique specific QPO excitation radius. Consequently, there is a
simple behaviour of dimensionless frequency represented by
a single continuous function having solely one maximum close to .
Only one of these models is compatible with the expectation of .
The other five models that involve the radial and vertical epicyclic
oscillations imply the existence of multiple resonant radii. This signifies a
more complicated behaviour of that cannot be represented by
single functions. Each of these five models is compatible with the expectation
of .Comment: 8 pages, 4 figures, accepted for publication in Astronomy &
Astrophysic
Design thinking, system thinking, Grounded Theory, and system dynamics modeling - An integrative methodology for social sciences and humanities
This paper concerns design thinking (Lawson, 1980), system thinking (systems theory) (von Bertalanffy, 1968), and system dynamics modeling as methodological platforms for analyzing large amounts of qualitative data and transforming it into quantitative mode. The aims of this article are to present an integral (mixed) research process including the design thinking process - a solution oriented approach applicable in the social sciences and humanities which enables to reveal causality in research on societal and behavioral issues. This integral approach is illustrated by an empirical pilot study from art/design-educational environment. © 2018 Eva Šviráková, Gabriel Bianchi, published by De Gruyter.Slovak research agency VEGA [2/0027/17
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