162,693 research outputs found
Does training with amplitude modulated tones affect tone-vocoded speech perception?
Temporal-envelope cues are essential for successful speech perception. We asked here whether training on stimuli containing temporal-envelope cues without speech content can improve the perception of spectrally-degraded (vocoded) speech in which the temporal-envelope (but not the temporal fine structure) is mainly preserved. Two groups of listeners were trained on different amplitude-modulation (AM) based tasks, either AM detection or AM-rate discrimination (21 blocks of 60 trials during two days, 1260 trials; frequency range: 4Hz, 8Hz, and 16Hz), while an additional control group did not undertake any training. Consonant identification in vocoded vowel-consonant-vowel stimuli was tested before and after training on the AM tasks (or at an equivalent time interval for the control group). Following training, only the trained groups showed a significant improvement in the perception of vocoded speech, but the improvement did not significantly differ from that observed for controls. Thus, we do not find convincing evidence that this amount of training with temporal-envelope cues without speech content provide significant benefit for vocoded speech intelligibility. Alternative training regimens using vocoded speech along the linguistic hierarchy should be explored
Determining the Actual Local Density of Dark Matter Particles
Even if dark matter particles are unambiguously discovered in experiments,
there is no clear reason to expect that the dark matter problem has been
solved. It is very easy to provide examples of dark matter scenarios (e.g. in
supersymmetric models) where nearly identical detector signals correspond to
extremely different relic densities. Therefore, the density of the particles
discovered must be determined before their cosmological relevance is
established. In this talk, I will present a general method to estimate the
local density of dark matter particles using both dark matter and hadron
collider experimental data when it becomes available. These results were
obtained in collaboration with Gordon Kane at the University of Michigan.Comment: 9 pages, 4 figures. Talk given at the 42nd International School of
Subnuclear Physics at Erice, Sicily, 30 August 200
Pulsational line profile variation of the roAp star HR 3831
We report the first comprehensive investigation of the line profile variation
caused by non-radial pulsation in a magnetic oscillating chemically peculiar
star. Spectrum variation of the well-known roAp star HR 3831 is detected using
very high-resolution high signal-to-noise spectroscopic time-series
observations and are followed through the whole rotation cycle of the star. We
confirm outstanding diversity of pulsational behaviour of different lines in
the HR 3831 spectrum and attribute this phenomenon to an interplay between
extreme vertical chemical inhomogeneity of the HR 3831 atmosphere and a running
pulsation wave, propagating towards the upper photospheric layers with
increasing amplitude. Rapid profile variation of the NdIII 6145 A line is
characterized by measuring changes of its equivalent width and the first three
moments. We demonstrate that rotational modulation of the radial velocity
oscillations cannot be fully explained by an oblique axisymmetric dipole
(ell=1, m=0) mode, implied by the classical oblique pulsator model of roAp
stars. Pulsational variation of the higher moments reveal substantial
contribution of the high-order (ell=3) spherical harmonics which appear due to
distortion of pulsations in HR 3831 by the global magnetic field. We interpret
observations with a novel numerical model of the pulsational variation and
rotational modulation of the line profile moments in roAp stars. The comparison
between observed and computed amplitudes and phases of the radial velocity and
line width variation is used to establish parameters of the oblique pulsator
model of HR 3831. Furthermore, definite detection of pulsational variation in
lines of light and iron-peak elements enables the first 3-D mapping of
pulsations in non-radially oscillating star.Comment: 21 pages, 11 figures; accepted by A&
Optical processing for landmark identification
A study of optical pattern recognition techniques, available components and airborne optical systems for use in landmark identification was conducted. A data base of imagery exhibiting multisensor, seasonal, snow and fog cover, exposure, and other differences was assembled. These were successfully processed in a scaling optical correlator using weighted matched spatial filter synthesis. Distinctive data classes were defined and a description of the data (with considerable input information and content information) emerged from this study. It has considerable merit with regard to the preprocessing needed and the image difference categories advanced. A optical pattern recognition airborne applications was developed, assembled and demontrated. It employed a laser diode light source and holographic optical elements in a new lensless matched spatial filter architecture with greatly reduced size and weight, as well as component positioning toleranced
Evaluating musical software using conceptual metaphors
An open challenge for interaction designers is to find ways of designing software to enhance the ability of novices to perform tasks that normally require specialized domain expertise. This challenge is particularly demanding in areas such as music analysis, where complex, abstract, domain-specific concepts and notations occur. One promising theoretical foundation for this work involves the identification of conceptual metaphors and image schemas, found by analyzing discourse. This kind of analysis has already been applied, with some success, both to musical concepts and, separately, to user interface design. The present work appears to be the first to combine these hitherto distinct bodies of research, with the aim of devising a general method for improving user interfaces for music. Some areas where this may require extensions to existing method are noted.
This paper presents the results of an exploratory evaluation of Harmony Space, a tool for playing, analysing and learning about harmony. The evaluation uses conceptual metaphors and image schemas elicited from the dialogues of experienced musicians discussing the harmonic progressions in a piece of music. Examples of where the user interface supports the conceptual metaphors, and where support could be improved, are discussed. The potential use of audio output to support conceptual metaphors and image schemas is considered
For whom will the Bayesian agents vote?
Within an agent-based model where moral classifications are socially learned,
we ask if a population of agents behaves in a way that may be compared with
conservative or liberal positions in the real political spectrum. We assume
that agents first experience a formative period, in which they adjust their
learning style acting as supervised Bayesian adaptive learners. The formative
phase is followed by a period of social influence by reinforcement learning. By
comparing data generated by the agents with data from a sample of 15000 Moral
Foundation questionnaires we found the following. 1. The number of information
exchanges in the formative phase correlates positively with statistics
identifying liberals in the social influence phase. This is consistent with
recent evidence that connects the dopamine receptor D4-7R gene, political
orientation and early age social clique size. 2. The learning algorithms that
result from the formative phase vary in the way they treat novelty and
corroborative information with more conservative-like agents treating it more
equally than liberal-like agents. This is consistent with the correlation
between political affiliation and the Openness personality trait reported in
the literature. 3. Under the increase of a model parameter interpreted as an
external pressure, the statistics of liberal agents resemble more those of
conservative agents, consistent with reports on the consequences of external
threats on measures of conservatism. We also show that in the social influence
phase liberal-like agents readapt much faster than conservative-like agents
when subjected to changes on the relevant set of moral issues. This suggests a
verifiable dynamical criterium for attaching liberal or conservative labels to
groups.Comment: 31 pages, 5 figure
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