24 research outputs found
Reforming the EU Sugar Policy
This article presents and analyses the impacts of the EU sugar policy. Particular attention is given to the modelling of the quite complex policy and the calibration of the global general equilibrium model at the member state level. Two scenarios are analysed, namely a reduction in the intervention price of sugar and the sugar quota. It is found that the economic impacts of the two scenarios are quite different in terms of the effects on European production and trade in sugar as well in terms of efficiency. The impacts for developing countries also differ considerably across the two scenarios.EU sugar policy, general equilibrium modelling, reform scenarios, Agricultural and Food Policy, C68, D58, Q17, Q18,
Evolved Eclipsing Binaries and the Age of the Open Cluster NGC 752
We present analyses of improved photometric and spectroscopic observations
for two detached eclipsing binaries at the turnoff of the open cluster NGC 752:
the 1.01 day binary DS And and the 15.53 d BD 37 410. For DS And, we find
, ,
, and . We either confirm or newly identify unusual characteristics of both
stars in the binary: the primary star is found to be slightly hotter than the
main sequence turn off and there is a more substantial discrepancy in its
luminosity compared to models (model luminosities are too large by about 40%),
while the secondary star is oversized and cooler compared to other main
sequence stars in the same cluster. The evidence points to non-standard
evolution for both stars, but most plausible paths cannot explain the low
luminosity of the primary star.
BD 37 410 only has one eclipse per cycle, but extensive spectroscopic
observations and the TESS light curve constrain the stellar masses well: and . The radius of the
main sequence primary star near definitively requires large
convective core overshooting ( pressure scale heights) in models for its
mass, and multiple lines of evidence point toward an age of
Gyr (statistical and systematic uncertainties). Because
NGC 752 is currently undergoing the transition from non-degenerate to
degenerate He ignition of its red clump stars, BD 37 410 A directly
constrains the star mass where this transition occurs.Comment: 34 pages, 23 figures, accepted for Astronomical Journa
Solar-like oscillations in the G2 subgiant beta Hydri from dual-site observations
We have observed oscillations in the nearby G2 subgiant star beta Hyi using
high-precision velocity observations obtained over more than a week with the
HARPS and UCLES spectrographs. The oscillation frequencies show a regular comb
structure, as expected for solar-like oscillations, but with several l=1 modes
being strongly affected by avoided crossings. The data, combined with those we
obtained five years earlier, allow us to identify 28 oscillation modes. By
scaling the large frequency separation from the Sun, we measure the mean
density of beta Hyi to an accuracy of 0.6%. The amplitudes of the oscillations
are about 2.5 times solar and the mode lifetime is 2.3 d. A detailed comparison
of the mixed l=1 modes with theoretical models should allow a precise estimate
of the age of the star.Comment: 13 pages, 14 figures, accepted by ApJ. Fixed minor typo (ref to Fig
14
GTAP at Work in Denmark - Quantifying and Qualifying a Political Debate
In March 1999 the Danish Minister of Food, Agriculture and Fisheries invited key policy makers from the food industry, farmers' organisations, consumer organisations and labour unions in Denmark to discuss the future perspectives for the Danish agricultural and fisheries sectors in a national and global context. In order to qualify and quantify the debate, the Danish Institute of Agricultural and Fisheries Economics (SJFI) was called upon to participate in the discussions and to assess the future development of the Danish agricultural sectors with the aim of identifying challenges and opportunities. SJFI was also asked to analyse the economic consequences of specific policy scenarios, including the impact of higher national standards in relation to environmental protection, animal welfare and food security. This paper describes how the SJFI team has put GTAP to work in a specific policy context demonstrating the applicability of computable general equilibrium (CGE) models for practical policy advise purposes. It is concluded that such model-based analysis - in spite of its limitations - has influenced the political debate in Denmark and that the strength of the CGE approach lies not so much in the exact numerical results, but rather in the focus on important economic mechanisms and linkages, thereby providing a structured analytical framework. Moreover, the Danish experience illustrates that using more formal analytical approaches such as CGE modelling contributes to a more focused, disciplined and hence a more constructive policy debat
Reforming the EU Sugar Policy
This article presents and analyses the impacts of the EU sugar policy. Particular attention is given to the modelling of the quite complex policy and the calibration of the global general equilibrium model at the member state level. Two scenarios are analysed, namely a reduction in the intervention price of sugar and the sugar quota. It is found that the economic impacts of the two scenarios are quite different in terms of the effects on European production and trade in sugar as well in terms of efficiency. The impacts for developing countries also differ considerably across the two scenarios