12,324 research outputs found
Dispelling the Anthropic Principle from the Dimensionality Arguments
It is shown that in d=11 supergravity, under a very reasonable ansatz, the
nearly flat spacetime in which we are living must be 4-dimensional without
appealing to the Anthropic Principle. Can we dispel the Anthropic Principle
completely from cosmology?Comment: 7 pages, Essa
Condensate wave function and elementary excitations of bosonic polar molecules: beyond the first Born approximation
We investigate the condensate wave function and elementary excitations of
strongly interacting bosonic polar molecules in a harmonic trap, treating the
scattering amplitude beyond the standard first Born approximation (FBA). By
using an appropriate trial wave function in the variational method, effects of
the leading order correction beyond the FBA have been investigated and shown to
be significantly enhanced when the system is close to the phase boundary of
collapse. How such leading order effect of going beyond the FBA can be observed
in a realistic experiment is also discussed.Comment: 7 pages, 4 figure
Identifying and Measuring the Effect of Firm Clusters Among Certified Organic Processors and Handlers
This paper investigates the certified organic handler sector, a specialized component of the middle part of the farm-to-table marketing chain, and documents the impacts of firm agglomeration (or firm clusters) on firm-level performance or firm-level decisions. After accounting for endogeneity in firm clustering, our findings confirm that firm clusters have significant impacts, though the estimate of the impact depends on how a firm cluster is defined. For example, significant impacts on sales per employee range from an additional 1.47 million, depending on whether a small or large number of firms is used as the minimum number to define a firm cluster.firm clusters, organic, treatment effects, Agribusiness, Agricultural and Food Policy, Community/Rural/Urban Development,
The Photonic Band theory and the negative refraction experiment of metallic helix metamaterials
We develop a theory to compute and interpret the photonic band structure of a
periodic array of metallic helices for the first time. Interesting features of
band structure include the ingenuous longitudinal and circularly polarized
eigenmodes, the wide polarization gap [Science 325, 1513 (2009)], and the
helical symmetry guarantees the existence of negative group velocity bands at
both sides of the polarization gap and band crossings pinned at the zone
boundary with fixed frequencies. A direct proof of negative refraction via a
chiral route [Science 306, 1353 (2004)] is achieved for the first time by
measuring Gooshanchen shift through a slab of three dimensional bona fide helix
metamaterial
The and decays with the fourth generation
If the fourth generation fermions exist, the new quarks could influence the
branching ratios of the decays of and . We
obtain two solutions of the fourth generation CKM factor
from the decay of . We use these
two solutions to calculate the new contributions of the fourth generation quark
to Wilson coefficients of the decay of . The branching ratio
and the forward-backward asymmetry of the decay of in the two
cases are calculated. Our results are quite different from that of SM in one
case, almost same in another case. If Nature chooses the formmer, the meson
decays could provide a possible test of the forth generation existence.Comment: 10 pages, 5 figure
Integrating Emotion Recognition with Speech Recognition and Speaker Diarisation for Conversations
Although automatic emotion recognition (AER) has recently drawn significant
research interest, most current AER studies use manually segmented utterances,
which are usually unavailable for dialogue systems. This paper proposes
integrating AER with automatic speech recognition (ASR) and speaker diarisation
(SD) in a jointly-trained system. Distinct output layers are built for four
sub-tasks including AER, ASR, voice activity detection and speaker
classification based on a shared encoder. Taking the audio of a conversation as
input, the integrated system finds all speech segments and transcribes the
corresponding emotion classes, word sequences, and speaker identities. Two
metrics are proposed to evaluate AER performance with automatic segmentation
based on time-weighted emotion and speaker classification errors. Results on
the IEMOCAP dataset show that the proposed system consistently outperforms two
baselines with separately trained single-task systems on AER, ASR and SD.Comment: Interspeech 202
Distribution-based Emotion Recognition in Conversation
Automatic emotion recognition in conversation (ERC) is crucial for
emotion-aware conversational artificial intelligence. This paper proposes a
distribution-based framework that formulates ERC as a sequence-to-sequence
problem for emotion distribution estimation. The inherent ambiguity of emotions
and the subjectivity of human perception lead to disagreements in emotion
labels, which is handled naturally in our framework from the perspective of
uncertainty estimation in emotion distributions. A Bayesian training loss is
introduced to improve the uncertainty estimation by conditioning each emotional
state on an utterance-specific Dirichlet prior distribution. Experimental
results on the IEMOCAP dataset show that ERC outperformed the
single-utterance-based system, and the proposed distribution-based ERC methods
have not only better classification accuracy, but also show improved
uncertainty estimation.Comment: To appear in SLT 202
A resonant feature near the Perseus arm revealed by red clump stars
We investigate the extinction together with the radial velocity dispersion
and distribution of red clump stars in the anti-center direction using spectra
obtained with Hectospec on the MMT. We find that extinction peaks at
Galactocentric radii of about 9.5 and 12.5 kpc, right in front of the locations
of the Perseus and Outer arms and in line with the relative position of dust
and stars in external spiral galaxies. The radial velocity dispersion peaks
around 10kpc, which coincides with the location of the Perseus arm, yields an
estimated arm-interarm density contrast of 1.3-1.5 and is in agreement with
previous studies. Finally, we discover that the radial velocity distribution
bifurcates around 10-11 kpc into two peaks at +27 km/s and -4 km/s. This seems
to be naturally explained by the presence of the outer Lindblad resonance of
the Galactic bar, but further observations will be needed to understand if the
corotation resonance of the spirals arms also plays a role.Comment: 8 pages, 2 figures, accepted for publication in ApJ
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