45,778 research outputs found
Ramadan school holidays as a natural experiment : impacts of seasonality on school dropout in Bangladesh
In 2000, Ramadan school vacation coincided with the original annual exam period of December in Bangladesh. This forced schools to pre-pone their final exam schedules in November, which was the month before the harvest begins. 'Ramadan 2000' is a natural experiment that reduced the labor demand for children during the exam period. Using household level panel data of 2000 and 2003, and after controlling for various unobservable variations including individual fixed effects, aggregate year effects, and subdistrict-level year effects, this paper finds evidence of statistically significant impact of seasonal labor demand on school dropout in Bangladesh among the children from agricultural households.Bangladesh, Child labor, Schools, Labor market, Drop out, Seasonal labor demand, School calendar
Spin-Polarization Response Functions in High-Energy (e,e'p) Reactions
Spin-polarization response functions are examined for high-energy
reaction by computing the full 18 response functions for
the proton kinetic energy 0.515 GeV and 3.179 GeV with an 16O target.
The Dirac eikonal formalism is applied to account for the final-state
interactions. The formalism is found to yield the response functions in good
agreement with those calculated by the partial-wave expansion method at 0.515
GeV. We identify the response functions that depend on the spin-orbital
potential in the final-state interactions, but not on the central potential.
Dependence on the Dirac- or Pauli-type current of the nucleon is investigated
in the helicity-dependent response functions, and the normal-component
polarization of the knocked-out proton, , is computed.Comment: 22 pages, Latex, figures available at
ftp://ftp.krl.caltech.edu/pub/users/rseki/it
Two Decades of Japanese Monetary Policy and the Deflation Problem
This paper reviews Japanese monetary policy over the last two decades with an emphasis on the experience of deflation from the mid-1990s. The paper is quite critical of the conduct of monetary policy, particularly from 1998 to 2003. The Bank of Japan's rhetoric was not helpful in fighting deflation, and the interest rate hike in August 2000 amid deflation was a serious mistake. Deflation can be quite costly, and a key element in both preventing and escaping deflation is the management of expectations, using either price level or inflation targeting, because the zero lower bound on interest rates means that the overnight interest rate can no longer be used as the instrument of monetary policy. This paper proposes how to best manage expectations to exit deflation. Price-level targeting overcomes theoretical problems, such as need for a history dependent strategy, associated with inflation targeting. However, because actions speak louder than words, management of expectations also involves non-conventional monetary policies, a combination of which might have to be tried to help the Japanese economy escape its deflationary trap.
Evolution of non-thermal emission from shell associated with AGN jets
We explore the evolution of the emissions by accelerated electrons in shocked
shells driven by jets in active galactic nuclei (AGNs). Focusing on powerful
sources which host luminous quasars, we evaluated the broadband emission
spectra by properly taking into account adiabatic and radiative cooling effects
on the electron distribution. The synchrotron radiation and inverse Compton
(IC) scattering of various photons that are mainly produced in the accretion
disc and dusty torus are considered as radiation processes. We show that the
resultant radiation is dominated by the IC emission for compact sources (<
10kpc), whereas the synchrotron radiation is more important for larger sources.
We also compare the shell emissions with those expected from the lobe under the
assumption that a fractions of the energy deposited in the shell and lobe
carried by the non-thermal electrons are and
, respectively. Then, we find that the shell
emissions are brighter than the lobe ones at infra-red and optical bands when
the source size is > 10kpc, and the IC emissions from the shell at > 10 GeV can
be observed with the absence of contamination from the lobe irrespective of the
source size. In particular, it is predicted that, for most powerful nearby
sources (), TeV gamma-rays produced via the IC
emissions can be detected by the modern Cherenkov telescopes such as MAGIC,
HESS and VERITAS.Comment: 13 pages, 5 figures, accepted for publication in Ap
Analysis of 2D THz-Raman spectroscopy using a non-Markovian Brownian oscillator model with nonlinear system-bath interactions
We explore and describe the roles of inter-molecular vibrations employing a
Brownian oscillator (BO) model with linear-linear (LL) and square-linear (SL)
system-bath interactions, which we use to analyze two-dimensional (2D)
THz-Raman spectra obtained by means of molecular dynamics (MD) simulations. In
addition to linear absorption (1D IR), we calculated 2D Raman-THz-THz,
THz-Raman-THz, and THz-THz-Raman signals for liquid formamide, water, and
methanol using an equilibrium non-equilibrium hybrid MD simulation. The
calculated 1D IR and 2D THz-Raman signals are compared with results obtained
from the LL+SL BO model applied through use of hierarchal Fokker-Planck
equations with non-perturbative and non-Markovian noise. We find that all of
the qualitative features of the 2D profiles of the signals obtained from the MD
simulations are reproduced with the LL+SL BO model, indicating that this model
captures the essential features of the inter-molecular motion. We analyze the
fitted 2D profiles in terms of anharmonicity, nonlinear polarizability, and
dephasing time. The origins of the echo peaks of the librational motion and the
elongated peaks parallel to the probe direction are elucidated using optical
Liouville paths.Comment: 37 pages with 14 figures and 3 table
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