2,271 research outputs found
A framework to evaluate and verify the presence of linguistic concepts in the prosody of spoken utterances
With recent developments in controlling the prosodic output of speech synthesizers[1], the quality of synthetic speech has improved considerably. However, determining the prosody required to convey specific linguistic concepts is still a largely unsolved problem. Concept-to-speech systems seem the most promising: additional information (structuring, focussing, affirmation/negation, quotation, enumeration, time/date, salutation, speaker attitude, etc.) is available to the prosody generation algorithm. This paper describes a method for determining which linguistic concepts are present in the prosody of a spoken utterance and which should therefore be taken into account when modelling prosody
Band structures of rare gas solids within the GW approximation
Band structures for solid rare gases (Ne, Ar) have been calculated using the
GW approximation. All electron and pseudopotential ab initio calculations were
performed using Gaussian orbital basis sets and the dependence of particle-hole
gaps and electron affinities on basis set and treatment of core electrons is
investigated. All electron GW calculations have a smaller particle-hole gap
than pseudopotential GW calculations by up to 0.2 eV. Quasiparticle electron
and hole excitation energies, valence band widths and electron affinities are
generally in very good agreement with those derived from optical absorption and
photoemission measurements.Comment: 7 pages 1 figur
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The Relationship between Fear and Stereotyped versus Non-Stereotyped Tasks
The exact properties of the interaction between emotional drives and other psychological phenomena is still a vastly unexplored field. The purpose of this paper will be to examine further the effects of one of these emotional drives, that of fear, on task performance, and to explore some of the theoretical conceptualizations already put forth regarding this interaction
Structure factors of harmonic and anharmonic Fibonacci chains by molecular dynamics simulations
The dynamics of quasicrystals is characterized by the existence of phason
excitations in addition to the usual phonon modes. In order to investigate
their interplay on an elementary level we resort to various one-dimensional
model systems. The main observables are the static, the incoherent, and the
coherent structure factor, which are extracted from molecular dynamics
simulations. For the validation of the algorithms, results for the harmonic
periodic chain are presented. We then study the Fibonacci chain with harmonic
and anharmonic interaction potentials. In the dynamic Fibonacci chain
neighboring atoms interact by double-well potentials allowing for phason flips.
The difference between the structure factors of the dynamic and the harmonic
Fibonacci chain lies in the temperature dependence of the phonon line width. If
a bias is introduced in the well depth, dispersionless optic phonon bands split
off.Comment: 12 pages, 15 figure
Short-term heat treatment of ti6al4v eli as implant material
Due to its mechanical properties and good biocompatibility, Ti6Al4V ELI (extra low interstitials) is widely used in medical technology, especially as material for implants. The specific microstructures that are approved for this purpose are listed in the standard ISO 20160:2006. Inductive short-term heat treatment is suitable for the adjustment of near-surface component properties such as residual stress conditions. A systematic evaluation of the Ti6Al4V microstructures resulting from short-term heat treatment is presently missing. In order to assess the parameter field that leads to suitable microstructures for load-bearing implants, dilatometer experiments have been conducted. For this purpose, dilatometer experiments with heating rates up to 1000 °C/s, holding times between 0.5 and 30 s and cooling rates of 100 and 1000 °C/s were systematically examined in the present study. Temperatures up to 950 °C and a holding time of 0.5 s led to microstructures, which are approved for medical applications according to the standard ISO 20160:2006. Below 950 °C, longer holding times can also be selected
Biosensing platform combining label-free and labelled analysis using Bloch surface waves
Bloch surface waves (BSW) propagating at the boundary of truncated photonic crystals (1D-PC) have emerged as an attractive approach for label-free sensing in plasmon-like sensor configurations. Due to the very low losses in such dielectric thin film stacks, BSW feature very low angular resonance widths compared to the surface plasmon resonance
(SPR) case. Besides label-free operation, the large field enhancement and the absence of quenching allow utilizing BSW coupled fluorescence detection to additionally sense the presence of fluorescent labels. This approach can be adapted to the case of angularly resolved resonance detection, thus giving rise to a combined label-free / labelled biosensor
platform. It features a parallel analysis of multiple spots arranged as a one-dimensional array inside a microfluidic channel of a disposable chip. Application of such a combined biosensing approach to the detection of the Angiopoietin-2 cancer biomarker in buffer solutions is reported
Computer simulation of crystallization kinetics with non-Poisson distributed nuclei
The influence of non-uniform distribution of nuclei on crystallization
kinetics of amorphous materials is investigated. This case cannot be described
by the well-known Johnson-Mehl-Avrami (JMA) equation, which is only valid under
the assumption of a spatially homogeneous nucleation probability. The results
of computer simulations of crystallization kinetics with nuclei distributed
according to a cluster and a hardcore distribution are compared with JMA
kinetics. The effects of the different distributions on the so-called Avrami
exponent are shown. Furthermore, we calculate the small-angle scattering
curves of the simulated structures which can be used to distinguish
experimentally between the three nucleation models under consideration.Comment: 14 pages including 7 postscript figures, uses epsf.sty and
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Tunneling electron induced rotation of a copper phthalocyanine molecule on Cu(111)
The rates of a hindered molecular rotation induced by tunneling electrons are evaluated using scattering theory within the sudden approximation. Our approach explains the excitation of copper phthalocyanine molecules (CuPc) on Cu(111) as revealed in a recent measurement of telegraph noise in a scanning tunneling microscopy experiment. A complete explanation of the experimental data is performed by computing the geometry of the adsorbed system, its electronic structure, and the energy transfer between tunneling electrons and the molecule's rotational degree of freedom. The results unambiguously show that tunneling electrons induce a frustrated rotation of the molecule. In addition, the theory determines the spatial distribution of the frustrated rotation excitation, confirming the striking dominance of two out of four molecular lobes in the observed excitation process. This lobe selectivity is attributed to the different hybridizations with the underlying substrate. © 2013 American Physical Society.J.S., A.S., C.A.B., and R.M. gratefully acknowledge financial support by the Deutsche Forschungsgemeinschaft through the SFB616 ‘Energy Dissipation at Surfaces.’ N.L. is supported by the ICT-FET Integrated Project AtMol (http://www.atmol.eu). M.C.C. thanks the Studienstiftung desdeutschen Volkes.Peer Reviewe
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