4,571 research outputs found
FOREWORD: Special Issue on Experimental Methods in Environmental, Natural Resource, and Agricultural Economics
Agricultural and Food Policy, Environmental Economics and Policy, Institutional and Behavioral Economics, Research Methods/ Statistical Methods,
Construction of an instrument for the measurement of educational philosophy
Thesis (M.Ed.)--Boston Universit
Silent speech: restoring the power of speech to people whose larynx has been removed
Every year, some 17,500 people in Europe and North America lose the power of speech after undergoing a laryngectomy, normally as a treatment for throat cancer. Several research groups have recently demonstrated that it is possible to restore speech to these people by using machine learning to learn the transformation from articulator movement to sound. In our project articulator movement is captured by a technique developed by our collaborators at Hull University called Permanent Magnet Articulography (PMA), which senses the changes of magnetic field caused by movements of small magnets attached to the lips and tongue. This solution, however, requires synchronous PMA-and-audio recordings for learning the transformation and, hence, it cannot be applied to people who have already lost their voice. Here we propose to investigate a variant of this technique in which the PMA data are used to drive an articulatory synthesiser, which generates speech acoustics by simulating the airflow through a computational model of the vocal tract. The project goals, participants, current status, and achievements of the project are discussed below.Universidad de Málaga. Campus de Excelencia Internacional AndalucĂa Tech
High velocity clouds in the Galactic All Sky Survey I. Catalogue
We present a catalogue of high-velocity clouds (HVCs) from the Galactic All
Sky Survey (GASS) of southern-sky neutral hydrogen, which has 57 mK sensitivity
and 1 km/s velocity resolution and was obtained with the Parkes Telescope. Our
catalogue has been derived from the stray-radiation corrected second release of
GASS. We describe the data and our method of identifying HVCs and analyse the
overall properties of the GASS population. We catalogue a total of 1693 HVCs at
declinations < 0 deg, including 1111 positive velocity HVCs and 582 negative
velocity HVCs. Our catalogue also includes 295 anomalous velocity clouds
(AVCs). The cloud line-widths of our HVC population have a median FWHM of ~19
km/s, which is lower than found in previous surveys. The completeness of our
catalogue is above 95% based on comparison with the HIPASS catalogue of HVCs,
upon which we improve with an order of magnitude in spectral resolution. We
find 758 new HVCs and AVCs with no HIPASS counterpart. The GASS catalogue will
shed an unprecedented light on the distribution and kinematic structure of
southern-sky HVCs, as well as delve further into the cloud populations that
make up the anomalous velocity gas of the Milky Way.Comment: 21 pages, 14 figures, accepted for publication in ApJ
The Stellar Halos of Massive Elliptical Galaxies II: Detailed Abundance Ratios at Large Radius
We study the radial dependence in stellar populations of 33 nearby early-type
galaxies with central stellar velocity dispersions sigma* > 150 km/s. We
measure stellar population properties in composite spectra, and use ratios of
these composites to highlight the largest spectral changes as a function of
radius. Based on stellar population modeling, the typical star at 2 R_e is old
(~10 Gyr), relatively metal poor ([Fe/H] -0.5), and alpha-enhanced
([Mg/Fe]~0.3). The stars were made rapidly at z~1.5-2 in shallow potential
wells. Declining radial gradients in [C/Fe], which follow [Fe/H], also arise
from rapid star formation timescales due to declining carbon yields from
low-metallicity massive stars. In contrast, [N/Fe] remains high at large
radius. Stars at large radius have different abundance ratio patterns from
stars in the center of any present-day galaxy, but are similar to Milky Way
thick disk stars. Our observations are thus consistent with a picture in which
the stellar outskirts are built up through minor mergers with disky galaxies
whose star formation is truncated early (z~1.5-2).Comment: ApJ in press, 12 pages, 6 figure
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