9,059 research outputs found
Trade and Child Labor : A General Equilibrium Analysis
This paper augments the existing literature on trade and child labor by exploring the effects of
terms of trade changes in the context of a three good general equilibrium model, where one
of the goods is a non-traded good. We find that under quasi-linear preferences the effect of
the terms of trade on child labor depends critically on the pattern of substitutability (or
complementarity) in the excess demand functions between the export good and the nontraded
good. We extend the analysis to the case of homothetic preferences and find that the
basic result is somewhat modified in a context where the marginal utility of income is affected
by the terms of trade. We also extend the analysis to the case where factors move freely
between the three goods as in a Heckscher-Ohlin type framework. Finally, we show that a
balanced budget policy of taxing the education of skilled families and subsidizing the
education of unskilled families must reduce child labor without any impact on aggregate
welfare
"Soft X-ray transient" outbursts which aren't soft
We have accumulated multiwavelength (X-ray, optical, radio) lightcurves for
the eight black hole X-ray binaries which have been observed to enter a
supposed `soft X-ray transient' outburst, but remained in the low/hard state
throughout the outburst. Comparison of the lightcurve morphologies, spectral
behaviour, properties of the quasi-periodic oscillations and the radio jet
provides the first study of such objects as a sub-class of X-ray transients.
However rather than assuming that these hard state X-ray transients are
different from the `canonical' soft X-ray transient, we prefer to consider the
possibility that new analysis of both soft and hard state X-ray transients in a
spectral context will provide a model capable of explaining the outburst
mechanisms of (almost) all black hole X-ray binaries.Comment: Accepted for publication in New Astronom
The Hard Truth about Some "Soft" X-ray Transients
We have accumulated multiwavelength lightcurves for eight black hole X-ray
binaries which have been observed to enter a supposed ``soft X-ray transient''
outburst, but which in fact remained in the low/hard state throughout the
outburst. Comparison of the lightcurve morphologies, spectral behaviour,
properties of the QPOs and the radio jet provides the first study of such
objects as a subclass of X-ray transients (XRTs). However, rather than assuming
that these hard state XRTs are different from ``canonical'' soft XRTs, we
prefer to consider the possibility that a new analysis of both soft and hard
state XRTs in a spectral context will provide a model capable of explaining the
outburst mechanisms for the majority of black hole X-ray binaries.Comment: 3 pages, 2 figures; to appear in the Proceedings of the 4th
Microquasar Workshop, 2002, eds. Durouchoux, Fuchs & Rodriguez, published by
the Center for Space Physics: Kolkat
Optimal quantum state reconstruction for cold trapped ions
We study the physical implementation of an optimal tomographic reconstruction
scheme for the case of determining the state of a multi-qubit system, where
trapped ions are used for defining qubits. The protocol is based on the use of
mutually unbiased measurements and on the physical information described in H.
H\"{a}ffner \emph{et. al} [Nature \textbf{438}, 643-646 (2005)]. We introduce
the concept of physical complexity for different types of unbiased measurements
and analyze their generation in terms of one and two qubit gates for trapped
ions.Comment: Accepted for publication in Phys. Rev. A as Rap. Com
Trade and child labor: a general equilibrium analysis
This paper augments the existing literature on trade and child labor by exploring the effects of terms of trade changes in the context of a three good general equilibrium model, where one of the goods is a non-traded good. We find that under quasi-linear preferences the effect of the terms of trade on child labor depends critically on the pattern of substitutability (or complimentarity) in the excess demand functions between the export good and the non-traded good. We extend the analysis to the case where factors move freely between the three goods as in a Heckscher-Ohlin type framework. Finally, we show that a balanced budget policy of taxing the education of skilled families and subsidizing the education of unskilled families must reduce child labor without any impact on aggregate welfare.Child labor ; Balance of payments
Ethnic networks and U.S. exports
This paper provides new estimates of the effects of ethnic networks on U.S. exports. In line with recent research, our dataset is a panel of exports from U.S. states to 29 foreign countries. Our analysis departs from the literature in two ways, both of which show that previous estimates of the ethnic-network elasticity of trade are sensitive to the restrictions imposed on the estimated models. Our first departure is to control for unobserved heterogeneity with properly specified fixed effects, which we can do because our dataset contains a time dimension absent from previous studies. Our second departure is to remove the restriction that the network effect is the same for all ethnicities. We find that ethnic-network effects are much larger than has been estimated previously, although they are important only for a subset of countries.Exports ; Regional economics
Kinetic study of adsorption and photo-decolorization of Reactive Red 198 on TiO2 surface
Recycling and reuse of wastewater after purification will reduce the environmental pollution as well as fulfill the increasing demand of water. Adsorption-based water treatment process is very popular for dye-house wastewater treatment. The present study deals with treatment of wastewater contaminated by reactive dye. TiO2 is used as adsorbent and the spent adsorbent has been regenerated by Advanced Oxidation Process (AOP), without using any other chemicals. TiO2 adsorbs dye molecules and then those dye molecules have been oxidized via a photocatalytic reaction in presence of UV irradiation. Kinetics of dye adsorption and photocatalytic oxidation reaction has been developed in this study. Photocatalyst adsorbent (TiO2) has been reused several times after regeneration. The activity of catalyst decreases after each cycle; due to poisoning cause by intermediate by-products. Kinetic of this catalyst deactivation has been incorporated with L–H model to develop the photocatalytic reaction kinetic model
Hyperon bulk viscosity in strong magnetic fields
We study the bulk viscosity of neutron star matter including
hyperons in the presence of quantizing magnetic fields. Relaxation time and
bulk viscosity due to both the non-leptonic weak process involving
hyperons and direct Urca processes are calculated here. In the presence of a
strong magnetic field of G, the hyperon bulk viscosity coefficient is
reduced whereas bulk viscosity coefficients due to direct Urca processes are
enhanced compared with their field free cases when many Landau levels are
populated by protons, electrons and muons.Comment: LaTex, 28 pages including 9 figures; new results are discussed in
section I
GRO J1744-28, search for the counterpart: infrared photometry and spectroscopy
Using VLT/ISAAC, we detected 2 candidate counterparts to the bursting pulsar
GRO J1744-28, one bright and one faint, within the X-ray error circles of
XMM-Newton and Chandra. In determining the spectral types of the counterparts
we applied 3 different extinction corrections; one for an all-sky value, one
for a Galactic Bulge value and one for a local value. We find the local value,
with an extinction law of alpha = 3.23 +- 0.01 is the only correction that
results in colours and magnitudes for both bright and faint counterparts
consistent with a small range of spectral types, and for the bright
counterpart, consistent with the spectroscopic identification. Photometry of
the faint candidate indicates it is a K7/M0 V star at a distance of 3.75 +- 1
kpc. This star would require a very low inclination angle (i < 9deg) to satisfy
the mass function constraints; however it cannot be excluded as the counterpart
without follow-up spectroscopy to detect emission signatures of accretion.
Photometry and spectroscopy of the bright candidate indicate it is most likely
a G/K III star. The spectrum does not show Br-gamma emission, a known indicator
of accretion. The bright star's magnitudes are in agreement with the
constraints placed on a probable counterpart by the calculations of Rappaport &
Joss (1997) for an evolved star that has had its envelope stripped. The mass
function indicates the counterpart should have M < 0.3 Msol for an inclination
of i >= 15deg; a stripped giant, or a main sequence M3+ V star are consistent
with this mass-function constraint. In both cases mass-transfer, if present,
will be by wind-accretion as the counterpart will not fill its Roche lobe given
the observed orbital period. The derived magnetic field of 2.4 x 10^{11} G will
inhibit accretion by the propeller effect, hence its quiescent state.Comment: 12 pages, 6 figures, 4 table, MNRAS accepted Changes to the content
and an increased analysis of the Galactic centre extinctio
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