4,272 research outputs found
Contributions of temporal encodings of voicing, voicelessness, fundamental frequency, and amplitude variation to audiovisual and auditory speech perception
Auditory and audio-visual speech perception was investigated using auditory signals of invariant spectral envelope that temporally encoded the presence of voiced and voiceless excitation, variations in amplitude envelope and F-0. In experiment 1, the contribution of the timing of voicing was compared in consonant identification to the additional effects of variations in F-0 and the amplitude of voiced speech. In audio-visual conditions only, amplitude variation slightly increased accuracy globally and for manner features. F-0 variation slightly increased overall accuracy and manner perception in auditory and audio-visual conditions. Experiment 2 examined consonant information derived from the presence and amplitude variation of voiceless speech in addition to that from voicing, F-0, and voiced speech amplitude. Binary indication of voiceless excitation improved accuracy overall and for voicing and manner. The amplitude variation of voiceless speech produced only a small increment in place of articulation scores. A final experiment examined audio-visual sentence perception using encodings of voiceless excitation and amplitude variation added to a signal representing voicing and F-0. There was a contribution of amplitude variation to sentence perception, but not of voiceless excitation. The timing of voiced and voiceless excitation appears to be the major temporal cues to consonant identity. (C) 1999 Acoustical Society of America. [S0001-4966(99)01410-1]
Narrative, identity, and recovery from serious mental illness: A life history of a runner
In recent years, researchers have investigated the psychological effects of exercise for people with mental health problems, often by focusing on how exercise may alleviate symptoms of mental illness. In this article I take a different tack to explore the ways in which exercise contributed a sense of meaning, purpose, and identity to the life of one individual named Ben, a runner diagnosed with schizophrenia. Drawing on life history data, I conducted an analysis of narrative to explore the narrative types that underlie Ben's stories of mental illness and exercise. For Ben, serious mental illness profoundly disrupted a pre-existing athletic identity removing agency, continuity, and coherence from his life story. By returning to exercise several years later, Ben reclaimed his athletic identity and reinstated some degree of narrative agency, continuity, and coherence. While the relationships between narrative, identity, and mental health are undoubtedly complex, Ben's story suggests that exercise can contribute to recovery by being a personally meaningful activity which reinforces identity and sense of self
Local Charge Excesses in Metallic Alloys: a Local Field Coherent Potential Approximation Theory
Electronic structure calculations performed on very large supercells have
shown that the local charge excesses in metallic alloys are related through
simple linear relations to the local electrostatic field resulting from
distribution of charges in the whole crystal.
By including local external fields in the single site Coherent Potential
Approximation theory, we develop a novel theoretical scheme in which the local
charge excesses for random alloys can be obtained as the responses to local
external fields. Our model maintains all the computational advantages of a
single site theory but allows for full charge relaxation at the impurity sites.
Through applications to CuPd and CuZn alloys, we find that, as a general rule,
non linear charge rearrangements occur at the impurity site as a consequence of
the complex phenomena related with the electronic screening of the external
potential. This nothwithstanding, we observe that linear relations hold between
charge excesses and external potentials, in quantitative agreement with the
mentioned supercell calculations, and well beyond the limits of linearity for
any other site property.Comment: 11 pages, 1 table, 7 figure
Holographic non-relativistic fermionic fixed point by the charged dilatonic black hole
Driven by the landscape of garden-variety condensed matter systems, we have
investigated how the dual spectral function behaves at the non-relativistic as
well as relativistic fermionic fixed point by considering the probe Dirac
fermion in an extremal charged dilatonic black hole with zero entropy. Although
the pattern for both of the appearance of flat band and emergence of Fermi
surface is qualitatively similar to that given by the probe fermion in the
extremal Reissner-Nordstrom AdS black hole, we find a distinctly different low
energy behavior around the Fermi surface, which can be traced back to the
different near horizon geometry. In particular, with the peculiar near horizon
geometry of our extremal charged dilatonic black hole, the low energy behavior
exhibits the universal linear dispersion relation and scaling property, where
the former indicates that the dual liquid is a Fermi one while the latter
implies that the dual liquid is not exactly of Landau Fermi type
Achieving equity through 'gender autonomy': the challenges for VET policy and practice
This paper is based on research carried out in an EU Fifth Framework project on 'Gender and Qualification'. The research partners from five European countries investigated the impact of gender segregation in European labour markets on vocational education and training, with particular regard to competences and qualifications. The research explored the part played by gender in the vocational education and training experiences of (i) young adults entering specific occupations in child care, electrical engineering and food preparation/service (ii) adults changing occupations
Point-charge electrostatics in disordered alloys
A simple analytic model of point-ion electrostatics has been previously
proposed in which the magnitude of the net charge q_i on each atom in an
ordered or random alloy depends linearly on the number N_i^(1) of unlike
neighbors in its first coordination shell. Point charges extracted from recent
large supercell (256-432 atom) local density approximation (LDA) calculations
of Cu-Zn random alloys now enable an assessment of the physical validity and
accuracy of the simple model. We find that this model accurately describes (i)
the trends in q_i vs. N_i^(1), particularly for fcc alloys, (ii) the magnitudes
of total electrostatic energies in random alloys, (iii) the relationships
between constant-occupation-averaged charges and Coulomb shifts
(i.e., the average over all sites occupied by either or atoms) in the
random alloy, and (iv) the linear relation between the site charge q_i and the
constant- charge-averaged Coulomb shift (i.e., the average over all sites with
the same charge) for fcc alloys. However, for bcc alloys the fluctuations
predicted by the model in the q_i vs. V_i relation exceed those found in the
LDA supercell calculations. We find that (a) the fluctuations present in the
model have a vanishing contribution to the electrostatic energy. (b)
Generalizing the model to include a dependence of the charge on the atoms in
the first three (two) shells in bcc (fcc) - rather than the first shell only -
removes the fluctuations, in complete agreement with the LDA data. We also
demonstrate an efficient way to extract charge transfer parameters of the
generalized model from LDA calculations on small unit cells.Comment: 15 pages, ReVTeX galley format, 7 eps figures embedded using psfig,
to be published in Phys. Rev.
Representations of the exceptional and other Lie algebras with integral eigenvalues of the Casimir operator
The uniformity, for the family of exceptional Lie algebras g, of the
decompositions of the powers of their adjoint representations is well-known now
for powers up to the fourth. The paper describes an extension of this
uniformity for the totally antisymmetrised n-th powers up to n=9, identifying
(see Tables 3 and 6) families of representations with integer eigenvalues
5,...,9 for the quadratic Casimir operator, in each case providing a formula
(see eq. (11) to (15)) for the dimensions of the representations in the family
as a function of D=dim g. This generalises previous results for powers j and
Casimir eigenvalues j, j<=4. Many intriguing, perhaps puzzling, features of the
dimension formulas are discussed and the possibility that they may be valid for
a wider class of not necessarily simple Lie algebras is considered.Comment: 16 pages, LaTeX, 1 figure, 9 tables; v2: presentation improved, typos
correcte
Mixed RG Flows and Hydrodynamics at Finite Holographic Screen
We consider quark-gluon plasma with chemical potential and study
renormalization group flows of transport coefficients in the framework of
gauge/gravity duality. We first study them using the flow equations and compare
the results with hydrodynamic results by calculating the Green functions on the
arbitrary slice. Two results match exactly. Transport coefficients at arbitrary
scale is ontained by calculating hydrodynamics Green functions. When either
momentum or charge vanishes, transport coefficients decouple from each other.Comment: 22 pages, 6 figure
A New Giant Branch Clump Structure In the Large Magellanic Cloud
We present Washington C, T1 CCD photometry of 21 fields located in the
northern part of the Large Magellanic Cloud (LMC), and spread over a region of
more than 2.52 degrees approximately 6 degrees from the bar. The surveyed areas
were chosen on the basis of their proximity to SL 388 and SL 509, whose fields
showed the presence of a secondary giant clump, observationally detected by
Bica et al. (1998, AJ, 116, 723). From the collected data we found that most of
the observed field CMDs do not show a separate secondary clump, but rather a
continuous vertical structure (VS), which is clearly seen for the first time.
Its position and size are nearly the same throughout the surveyed regions: it
lies below the Red Giant Clump (RGC) and extends from the bottom of the RGC to
approximately 0.45 mag fainter, spanning the bluest color range of the RGC. The
more numerous the VS stars in a field, the larger the number of LMC giants in
the same zone. Our analysis demonstrate that VS stars belong to the LMC and are
most likely the consequence of some kind of evolutionary process in the LMC,
particularly in those LMC regions with a noticeable large giant population. Our
results suggest that in order to trigger the formation of VS stars, there
should be other conditions besides the appropriate age, metallicity, and the
necessary red giant star density. Indeed, stars satisfying the requisites
mentioned above are commonly found throughout the LMC, but the VS phenomenon is
only clearly seen in some isolated regions. Finally, the fact that clump stars
have an intrinsic luminosity dispersion further constrains the use of the clump
magnitude as a reliable distance indicator.Comment: 25 pages, 9 figures, 3 tables; to be published in AJ, Dec. issu
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