1,369 research outputs found
Can EU Conditionality Remedy Soft Budget Constraints in Transition Countries?
Soft budget constraints (SBCs) are a persistent feature of transition economies and have been blamed for i.a. a lack of fiscal consolidation and sluggish growth. EU eastward enlargement has - among other things - been conditioned on tackling SBCs. This paper analyzes such outside conditionality theoretically and empirically. First, modelling the SBC problem as a war of attrition between the applicant countries' governments and firms we find that outside conditionality can foster SBC hardening. Yet, toughening the EU stance or reducing the number of enlargement rounds may have ambiguous effects. Second, estimating SBC hardening in a partial adjustment model by measuring the reaction of employment to output changes we find that EU conditionality did indeed help candidates to fight SBCs.soft budget constraint, EU enlargement, war of attrition
Doorkeepers and Gatecrashers: EU Enlargement and Negotiation Strategies
This paper discusses the eastward enlargement process of the EU in the framework of a simple war of attrition bargaining game. Both players - the existing EU members and the applicants - benefit from enlargement, yet for the applicants reform to the acquis is costly, while the EU prefers substantially reformed candidates. A waiting game unfolds. Within this framework the present enlargement round is analyzed and policy results are deduced. For example, it is shown that delegating the evaluation of applicants to a third party, compensating applicants for their reform efforts or increasing the benefits for new members are all effective negotiation strategies for the EU that have been applied in the process.EU enlargement, eastern enlargement, bargaining, reform, war of attrition.
Open-charm enhancement at FAIR?
We have calculated the D-meson spectral density at finite temperature within
a self-consistent coupled-channel approach that generates dynamically the
(2593) resonance. We find a small mass shift for the D-meson in
this hot and dense medium while the spectral density develops a sizeable width.
The reduced attraction felt by the D-meson in hot and dense matter together
with the large width observed have important consequences for the D-meson
production in the future CBM experiment at FAIR.Comment: 4 pages, 2 figures, to appear in the proceedings of 9th International
Conference on Strangeness in Quark Matter (SQM2006), Los Angeles, USA, March
26-31, 200
The in-medium isovector pi N amplitude from low energy pion scattering
Differential cross sections for elastic scattering of 21.5 MeV positive and
negative pions by Si, Ca, Ni and Zr have been measured as part of a study of
the pion-nucleus potential across threshold. The `anomalous' repulsion in the
s-wave term was observed, as is the case with pionic atoms. The extra repulsion
can be accounted for by a chiral-motivated model where the pion decay constant
is modified in the medium. Unlike in pionic atoms, the anomaly cannot be
removed by merely introducing an empirical on-shell energy dependence.Comment: 9 pages, 2 figures. Minor changes, to appear in PR
Evolution of trace gases and particles emitted by a chaparral fire in California
Biomass burning (BB) is a major global source of trace gases and particles. Accurately representing the production and evolution of these emissions is an important goal for atmospheric chemical transport models. We measured a suite of gases and aerosols emitted from an 81 hectare prescribed fire in chaparral fuels on the central coast of California, US on 17 November 2009. We also measured physical and chemical changes that occurred in the isolated downwind plume in the first ~4 h after emission. The measurements were carried out onboard a Twin Otter aircraft outfitted with an airborne Fourier transform infrared spectrometer (AFTIR), aerosol mass spectrometer (AMS), single particle soot photometer (SP2), nephelometer, LiCor CO_2 analyzer, a chemiluminescence ozone instrument, and a wing-mounted meteorological probe. Our measurements included: CO_2; CO; NO_x; NH_3; non-methane organic compounds; organic aerosol (OA); inorganic aerosol (nitrate, ammonium, sulfate, and chloride); aerosol light scattering; refractory black carbon (rBC); and ambient temperature, relative humidity, barometric pressure, and three-dimensional wind velocity. The molar ratio of excess O_3 to excess CO in the plume (ΔO_3/ΔCO) increased from −5.13 (±1.13) × 10^(−3) to 10.2 (±2.16) × 10^(−2) in ~4.5 h following smoke emission. Excess acetic and formic acid (normalized to excess CO) increased by factors of 1.73 ± 0.43 and 7.34 ± 3.03 (respectively) over the same time since emission. Based on the rapid decay of C_2H_4 we infer an in-plume average OH concentration of 5.27 (±0.97) × 10^6 molec cm^(−3), consistent with previous studies showing elevated OH concentrations in biomass burning plumes. Ammonium, nitrate, and sulfate all increased over the course of 4 h. The observed ammonium increase was a factor of 3.90 ± 2.93 in about 4 h, but accounted for just ~36% of the gaseous ammonia lost on a molar basis. Some of the gas phase NH_3 loss may have been due to condensation on, or formation of, particles below the AMS detection range. NO_x was converted to PAN and particle nitrate with PAN production being about two times greater than production of observable nitrate in the first ~4 h following emission. The excess aerosol light scattering in the plume (normalized to excess CO_2) increased by a factor of 2.50 ± 0.74 over 4 h. The increase in light scattering was similar to that observed in an earlier study of a biomass burning plume in Mexico where significant secondary formation of OA closely tracked the increase in scattering. In the California plume, however, ΔOA/ΔCO_2 decreased sharply for the first hour and then increased slowly with a net decrease of ~20% over 4 h. The fraction of thickly coated rBC particles increased up to ~85% over the 4 h aging period. Decreasing OA accompanied by increased scattering/particle coating in initial aging may be due to a combination of particle coagulation and evaporation processes. Recondensation of species initially evaporated from the particles may have contributed to the subsequent slow rise in OA. We compare our results to observations from other plume aging studies and suggest that differences in environmental factors such as smoke concentration, oxidant concentration, actinic flux, and RH contribute significantly to the variation in plume evolution observations
Stochastic optimization of a cold atom experiment using a genetic algorithm
We employ an evolutionary algorithm to automatically optimize different
stages of a cold atom experiment without human intervention. This approach
closes the loop between computer based experimental control systems and
automatic real time analysis and can be applied to a wide range of experimental
situations. The genetic algorithm quickly and reliably converges to the most
performing parameter set independent of the starting population. Especially in
many-dimensional or connected parameter spaces the automatic optimization
outperforms a manual search.Comment: 4 pages, 3 figure
Calculations of Resonance Coupling Constants in the Scalar Sector of the ENJL Model
We derive the scalar resonance coupling constants of resonance chiral theory
from the Extended Nambu Jona-Lasinio model by using heat-kernel expansion.Comment: 7 page
Entropy production by resonance decays
We investigate entropy production for an expanding system of particles and
resonances with isospin symmetry -- in our case pions and mesons --
within the framework of relativistic kinetic theory. A cascade code to simulate
the kinetic equations is developed and results for entropy production and
particle spectra are presented.Comment: 17 pages, 10 ps-figures included, only change: preprint number adde
Automatic 3D facial model and texture reconstruction from range scans
This paper presents a fully automatic approach to fitting a generic facial model to detailed range scans of human faces to reconstruct 3D facial models and textures with no manual intervention (such as specifying landmarks). A Scaling Iterative Closest Points (SICP) algorithm is introduced to compute the optimal rigid registrations between the generic model and the range scans with different sizes. And then a new template-fitting method, formulated in an optmization framework of minimizing the physically based elastic energy derived from thin shells, faithfully reconstructs the surfaces and the textures from the range scans and yields dense point correspondences across the reconstructed facial models. Finally, we demonstrate a facial expression transfer method to clone facial expressions from the generic model onto the reconstructed facial models by using the deformation transfer technique
Bioassay of Geniculosporium species for Phytophthora megakarya biological control on cacao pod husk pieces
Fungal endophytes (Geniculosporium sp.) isolated from cacao leaves were screened for biological control of Phytophthora megakarya the cacao black pod disease pathogen, using Cacao Pod Husk Pieces (CPHP). CPHP were pre-treated with spore suspensions of Geniculosporium sp. [BC13 (GJS 01- 196), BC108 (GJS 01-192), BC118 (GJS 01-197), BC177 (GJS 01-198)], and were infected with P. megakarya zoospore suspensions (105 zoospores/ml). Effects on P. megakarya were noticed at pod infection, mycelia growth inside infected tissues, and fungal sporulation, that are major stages of the black pod disease cycle on cacao pods. CPHP pre-treated with BC108 expressed the lowest early Infection Index (EII), but could not control disease progress into infected cacao pod husk tissues. On CPHP pre-treated with BC13, average growth rate of the necrosis was significantly reduced, but no control on P. megakarya sporulation was observed, while CPHP pre-treated with BC177 significantly reduced P. megakarya sporulation.Key words: Cacao, biological control, Geniculosporium sp, endophytes, Phytophthora megakarya, pod husks pieces
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