56,214 research outputs found
Language Identification Using Visual Features
Automatic visual language identification (VLID) is the technology of using information derived from the visual appearance and movement of the speech articulators to iden- tify the language being spoken, without the use of any audio information. This technique for language identification (LID) is useful in situations in which conventional audio processing is ineffective (very noisy environments), or impossible (no audio signal is available). Research in this field is also beneficial in the related field of automatic lip-reading. This paper introduces several methods for visual language identification (VLID). They are based upon audio LID techniques, which exploit language phonology and phonotactics to discriminate languages. We show that VLID is possible in a speaker-dependent mode by discrimi- nating different languages spoken by an individual, and we then extend the technique to speaker-independent operation, taking pains to ensure that discrimination is not due to artefacts, either visual (e.g. skin-tone) or audio (e.g. rate of speaking). Although the low accuracy of visual speech recognition currently limits the performance of VLID, we can obtain an error-rate of < 10% in discriminating between Arabic and English on 19 speakers and using about 30s of visual speech
A Trackable Model of Reciprocity and Fairness.
We introduced a parametric model of other-regarding preferences in which my emotional state determines the marginal rate of substitution between my own and other' payoffs, and thus my subsequent choices. In turn, my emotional state responds to relative status and to the kindness or unkindness of others' choices. Structural estimations of this model with six existing data sets demonstrate that other-regarding preferences depend on status, reciprocity, and perceived property rights.RECIPROCITY ; MARGINAL RATE OF SUBSTITUTION ; PAYOFFS
Synthesis of a Versatile Building Block for the Preparation of 6-N-Derivatized α-Galactosyl Ceramides: Rapid Access to Biologically Active Glycolipids
A concise route to the 6-azido-6-deoxy-α-galactosyl-phytosphingosine derivative 9 is reported. Orthogonal protection of the two amino groups allows elaboration of 9 into a range of 6-N-derivatized α-galactosyl ceramides by late-stage introduction of the acyl chain of the ceramide and the 6-N-group in the sugar head-group. Biologically active glycolipids 6 and 8 have been synthesized to illustrate the applicability of the approach
Differential Scattering Cross-Sections for the Different Product Vibrational States in the Ion-Molecule Reaction Ar+ + N2
The charge transfer reaction Ar+ + N2 --> Ar + N2+ has been investigated in a
crossed beam experiment in combination with three-dimensional velocity map
imaging. Angular differential state-to-state cross sections were determined as
a function of the collision energy. We found that scattering into the first
excited vibrational level dominates as expected, but only for scattering in the
forward direction. Higher vibrational excitations up to v'=6 have been observed
for larger scattering angles. For decreasing collision energy, scattering into
higher scattering angles becomes increasingly important for all kinematically
allowed quantum states. Our detailed measurements indicate that a quantitative
agreement between experiment and theory for this basic ion-molecule reaction
now comes within reach.Comment: accepted to Phys. Rev. Let
Observing a Light CP-Violating Higgs Boson in Diffraction
Light CP-violating Higgs bosons with mass lower than 70 GeV might have
escaped detection in direct searches at the LEP collider. They may remain
undetected in conventional search channels at the Tevatron and LHC. In this
Letter we show that exclusive diffractive reactions may be able to probe for
the existence of these otherwise elusive Higgs particles. As a prototype
example, we calculate diffractive production cross-sections of the lightest
Higgs boson within the framework of the Minimal Supersymmetric Standard Model
with explicit CP violation. Our analysis shows that the challenging regions of
parameter space corresponding to a light CP-violating Higgs boson might be
accessible at the LHC provided suitable proton tagging detectors are installed.Comment: 9 pages, LaTeX, 2 figures, version as to appear in Phys. Rev.
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