372 research outputs found
NoLACE: Improving Low-Complexity Speech Codec Enhancement Through Adaptive Temporal Shaping
Speech codec enhancement methods are designed to remove distortions added by
speech codecs. While classical methods are very low in complexity and add zero
delay, their effectiveness is rather limited. Compared to that, DNN-based
methods deliver higher quality but they are typically high in complexity and/or
require delay. The recently proposed Linear Adaptive Coding Enhancer (LACE)
addresses this problem by combining DNNs with classical long-term/short-term
postfiltering resulting in a causal low-complexity model. A short-coming of the
LACE model is, however, that quality quickly saturates when the model size is
scaled up. To mitigate this problem, we propose a novel adatpive temporal
shaping module that adds high temporal resolution to the LACE model resulting
in the Non-Linear Adaptive Coding Enhancer (NoLACE). We adapt NoLACE to enhance
the Opus codec and show that NoLACE significantly outperforms both the Opus
baseline and an enlarged LACE model at 6, 9 and 12 kb/s. We also show that LACE
and NoLACE are well-behaved when used with an ASR system.Comment: submitted to ICASSP 202
Dynamical Mass Estimates for Five Young Massive Stellar Clusters
We have obtained high-dispersion spectra for four massive star clusters in
the dwarf irregular galaxies NGC 4214 and NGC 4449, using the HIRES
spectrograph on the Keck I telescope. Combining the velocity dispersions of the
clusters with structural parameters and photometry from images taken with HST,
we estimate mass-to-light ratios and compare these with simple stellar
population (SSP) models in order to constrain the stellar mass functions (MFs).
For all clusters we find mass-to-light ratios which are similar to or slightly
higher than for a Kroupa MF, and thereby rule out any MF which is deficient in
low-mass stars compared to a Kroupa-type MF. The four clusters have virial
masses ranging between 2.1E5 Msun and 1.5E6 Msun, half-light radii between 3.0
and 5.2 pc, estimated core densities in the range 2E3 Msun pc^-3 to 2E5 Msun
pc^-3 and ages between 200 Myr and 800 Myr. We also present new high-dispersion
near-infrared spectroscopy for a luminous young (about 15 Myr) cluster in the
nearby spiral galaxy NGC 6946, which we have previously observed with HIRES.
The new measurements in the infrared agree well with previous estimates of the
velocity dispersion, yielding a mass of about 1.7E6 Msun. The properties of the
clusters studied here are all consistent with the clusters being young versions
of the old globular clusters found around all major galaxies.Comment: 30 pages, including 7 figures and 9 tables. Corrected an error in
Table 2: The colors listed for N6946-1447 were not reddening corrected. This
also affected Table 9 and Fig 2, 6 and
A sex-specific switch between visual and olfactory inputs underlies adaptive sex differences in behavior
While males and females largely share the same genome and nervous system, they
differ profoundly in reproductive investments and require distinct behavioral,
morphological and physiological adaptations. How can the nervous system, while
bound by both developmental and biophysical constraints, produce these sexdifferences in behavior? Here we uncover a novel dimorphism in Drosophila
melanogaster that allows deployment of completely different behavioral repertoires in
males and females with minimum changes to circuit architecture. Sexual differentiation
of only a small number of higher-order neurons in the brain leads to a change in
connectivity related to the primary reproductive needs of both sexes - courtship pursuit
in males and communal oviposition in females. This study explains how an apparently
similar brain generates distinct behavioral repertoires in the two sexes and presents a
fundamental principle of neural circuit organization that may be extended to other
species
Norms of Presentational Force
This is the author's accepted manuscript, made available with permission of the American Forensic Association.Can style or presentational devices reasonably compel us to believe, agree, act? I submit that they can, and that the normative pragmatic project explains how. After describing a normative pragmatic approach to presentational force, I analyze and evaluate presentational force in Susan B. Anthony's "Is it a Crime for a U. S. Citizen to Vote" as it apparently proceeds from logic, emotion, and style. I conclude with reflections on the compatibility of the normative pragmatic approach with the recently-developed pragma-dialectical treatment of presentational devices
Leading through agonistic conflict: Contested sense-making in national political arenas
This article examines the social processes of political leadership in situations of contest and conflict, taking place within a key and long-established democratic institution, the UK Parliament. The empirical focus is on leadership in House of Commons select committees, which are concerned with holding the government to account. Headlines and media scrutiny, combined with internal challenge from the cross-party mix of politicians on the committees and a range of external stakeholders, create leadership challenges for committee chairs. The study is of two committee inquiries led by the same committee chair, which occurred concurrently and in real time, thereby providing a rare comparative study of leadership through the same leader at the same time but with different leadership challenges. Rather than shying away from conflict, as does much of the leadership literature, this research highlights how leaders who actively engage in challenge and conflict can build a degree of shared purpose among diverse groups of stakeholders. It examines and combines, in theory elaboration, two theories relevant to understanding these leadership processes: agonistic pluralism with its role in creating respectful conflictual consensus, and the theory of sense-making and sense-giving. The two cases (the two inquiries) had different trajectories and reveal how the chair recognised and dealt with conflict to achieve sense-making outcomes across divergent interests and across political parties. There are implications not only for understanding political leadership but also more widely for leadership where there are diverse and sometimes conflicting interests
Complete genome sequence of Dehalogenimonas lykanthroporepellens type strain (BL-DC-9T) and comparison to “Dehalococcoides” strains
Dehalogenimonas lykanthroporepellens is the type species of the genus Dehalogenimonas, which belongs to a deeply branching lineage within the phylum Chloroflexi. This strictly anaerobic, mesophilic, non spore-forming, Gram-negative staining bacterium was first isolated from chlorinated solvent contaminated groundwater at a Superfund site located near Baton Rouge, Louisiana, USA. D. lykanthroporepellens was of interest for genome sequencing for two reasons: (a) an unusual ability to couple growth with reductive dechlorination of environmentally important polychlorinated aliphatic alkanes and (b) a phylogenetic position that is distant from previously sequenced bacteria. The 1,686,510 bp circular chromosome of strain BL-DC-9T contains 1,720 predicted protein coding genes, 47 tRNA genes, a single large subunit rRNA (23S-5S) locus, and a single, orphan, small subunit rRNA (16S) locus
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The rise of britain's super-indies: Policy-making in the age of the global media market
This article analyses Britain’s remarkable performance in the European television industry. In the space of a few years the UK has risen to become the world’s leading exporter of TV formats and the world’s second exporter, behind the Unites States, of finished TV programmes. The first section compares and contrasts British TV exports data with that of France, before examining the emergence of London as Europe’s media hub. The second part argues that this significant progress is essentially due to deft policy making. In 2003, the British government operated a strategic shift in favour of content producers and created a new intellectual property regime. This regime has enabled producers to keep hold of their rights and become asset-owning businesses, eventually giving rise to a new breed of production companies: the super-indies. This paper shows how these super-indies have acquired the scale to compete in an international TV market and drive today’s British TV exports. Contrasting again Britain’s performance in the European TV trade with France, this article also analyses historical influences and claims it is Britain’s imperial past that helps her performance in the European TV marketplace. In addition to the globalization of the English language and the cultural affinities this nurtures, the trading heritage of the British Empire has facilitated Britain’s political elite’s understanding of the role that trade and the market can play in the creative industries, and enabled them to frame a broadcasting policy that is adapted to the global age
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