33,679 research outputs found
El impacto de la privatización del sector eléctrico en la salud pública
Este informe utiliza información a nivel provincial en Argentina para probar la relación casual entre la distribución de electricidad y la salud. Examina el impacto de la privatización en dos medidas: incidencia en los índices de nacimientos de bajo peso y mortalidad infantil causada por envenenamiento de comida. La privatizacion mejora la cobertura del servicio que, a través del uso de refrigeradoras puede mejorar la ración nutricional. La privatización también tiene por resultado la reducción en la frecuencia de interrupciones eléctricas, y así reducir la probabilidad del envenenamiento de la comida. A pesar que la evidencia indica que la privatización reduce el índice de nacimientos de bajo peso y mortalidad infantil causados por el envenenamiento de la comida, los resultados no son lo suficientemente fuertes para enriquecer el debate de políticasrespecto a los beneficios de la privatización para el bienestar de los pobres.
Technical Change and Catching-up: The Electricity Distribution Sector in South America
The main purpose of this paper is to analyze technical change in the electricity distribution sector in South America, in the period 1994-1997. We do so by estimating a Maximum Likelihood stochastic frontier. We found that there is no evidence of catching up effects in the sector during this period. Besides, there is partial evidence that suggests that countries which reformed their electricity sector had a better performance than those which did not. We also found an increase in the capital share in the countries that made the reform and an increment in the labor share in the ones that did not make the reform.Technical change; Catching-Up; Stochastic frontier
The Critical Point of Unoriented Random Surfaces with a Non-Even Potential
The discrete model of the real symmetric one-matrix ensemble is analyzed with
a cubic interaction. The partition function is found to satisfy a recursion
relation that solves the model. The double-scaling limit of the recursion
relation leads to a Miura transformation relating the contributions to the free
energy coming from oriented and unoriented random surfaces. This transformation
is the same kind as found with a cuartic interaction.Comment: 20p (Frontpage included
Inhomogenous loop quantum cosmology with matter
The linearly polarized Gowdy model with a massless scalar field with
the same symmetries as the metric is quantized by applying a hybrid approach.
The homogeneous geometry degrees of freedom are loop quantized, fact which
leads to the resolution of the cosmological singularity, while a Fock
quantization is employed for both matter and gravitational inhomogeneities.
Owing to the inclusion of the massless scalar field this system allows us to
modelize flat Friedmann-Robertson-Walker cosmologies filled with
inhomogeneities propagating in one direction. It provides a perfect scenario to
study the quantum back-reaction between the inhomogeneities and the polymeric
homogeneous and isotropic background.Comment: 4 pages, Contribution to the proceedings of the Loops 11-Madrid
conferenc
Approximation methods in Loop Quantum Cosmology: From Gowdy cosmologies to inhomogeneous models in Friedmann-Robertson-Walker geometries
We develop approximation methods in the hybrid quantization of the Gowdy
model with linear polarization and a massless scalar field, for the case of
three-torus spatial topology. The loop quantization of the homogeneous
gravitational sector of the Gowdy model (according to the improved dynamics
prescription) and the presence of inhomogeneities lead to a very complicated
Hamiltonian constraint. Therefore, the extraction of physical results calls for
the introduction of well justified approximations. We first show how to
approximate the homogeneous part of the Hamiltonian constraint, corresponding
to Bianchi I geometries, as if it described a Friedmann-Robertson-Walker (FRW)
model corrected with anisotropies. This approximation is valid in the
high-energy sector of the FRW geometry (concerning its contribution to the
constraint) and for anisotropy profiles that are sufficiently smooth. In
addition, for certain families of states associated to regimes of physical
interest, with negligible effects of the anisotropies and small
inhomogeneities, one can approximate the Hamiltonian constraint of the
inhomogeneous system by that of an FRW geometry with a relatively simple matter
content, and then obtain its solutions.Comment: 20 pages, 3 figures. Minor changes, matches published versio
Inclusion of matter in inhomogeneous loop quantum cosmology
We study the hybrid quantization of the linearly polarized Gowdy model
with a massless scalar field with the same symmetries as the metric. For
simplicity, we quantize its restriction to the model with local rotational
symmetry. Using this hybrid approach, the homogeneous degrees of freedom of the
geometry are quantized \`a la loop, leading to the resolution of the
cosmological singularity. A Fock quantization is employed both for the matter
and the gravitational inhomogeneities. Owing to the inclusion of the massless
scalar field this system allows us to modelize flat Friedmann-Robertson-Walker
cosmologies filled with inhomogeneities propagating in one direction, providing
a perfect scenario to study the quantum back-reaction of the inhomogeneities on
the polymeric homogeneous and isotropic background.Comment: 4 pages. Contribution to the Proceedings of Spanish Relativity
Meeting ERE2011, Madrid 201
Dynamical variables in Gauge-Translational Gravity
Assuming that the natural gauge group of gravity is given by the group of
isometries of a given space, for a maximally symmetric space we derive a model
in which gravity is essentially a gauge theory of translations. Starting from
first principles we verify that a nonlinear realization of the symmetry
provides the general structure of this gauge theory, leading to a simple choice
of dynamical variables of the gravity field corresponding, at first order, to a
diagonal matrix, whereas the non-diagonal elements contribute only to higher
orders.Comment: 15 page
The Cost of Capital in Regulated Firms: The Argentine Experience
The sustainability of service is one of the fundamental aims of any regulatory system, and this tends to be reflected in the general principles within the legal framework of each public service. The necessity to cover economic costs of service then follows, in order to cover costs in such a way as to guarantee the maintaining and continuity of the system as well as its expansion. These economic costs should necessarily include sufficient retribution for the capital used by investors: the cost of capital. In the case of Argentine regulation, it is usual practice to use an adapted form of the CAPM (Capital Asset Pricing Model) to calculate the opportunity cost of equity, in such a way as to take the country risk into account. In this work we will analyse the components of the adapted formula for the cost of capital, discussing incentives which generate each of the possible outcomes for the regulated firms. Finally, we will present a model of dynamic optimisation for a regulated firm in a country such as Argentina.regulatory system; public service; CAPM; country risk
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