6,091 research outputs found
Scaling Speech Enhancement in Unseen Environments with Noise Embeddings
We address the problem of speech enhancement generalisation to unseen
environments by performing two manipulations. First, we embed an additional
recording from the environment alone, and use this embedding to alter
activations in the main enhancement subnetwork. Second, we scale the number of
noise environments present at training time to 16,784 different environments.
Experiment results show that both manipulations reduce word error rates of a
pretrained speech recognition system and improve enhancement quality according
to a number of performance measures. Specifically, our best model reduces the
word error rate from 34.04% on noisy speech to 15.46% on the enhanced speech.
Enhanced audio samples can be found in
https://speechenhancement.page.link/samples
Topological Phase Transitions in Line-nodal Superconductors
Fathoming interplay between symmetry and topology of many-electron
wave-functions has deepened understanding of quantum many body systems,
especially after the discovery of topological insulators. Topology of electron
wave-functions enforces and protects emergent gapless excitations, and symmetry
is intrinsically tied to the topological protection in a certain class. Namely,
unless the symmetry is broken, the topological nature is intact. We show novel
interplay phenomena between symmetry and topology in topological phase
transitions associated with line-nodal superconductors. The interplay may
induce an exotic universality class in sharp contrast to that of the
phenomenological Landau-Ginzburg theory. Hyper-scaling violation and emergent
relativistic scaling are main characteristics, and the interplay even induces
unusually large quantum critical region. We propose characteristic experimental
signatures around the phase transitions in three spatial dimensions, for
example, a linear phase boundary in a temperature-tuning parameter
phase-diagram.Comment: 4 + 23 pages, 7 figures, 1 table; the first two authors contributed
equally to this wor
The Koreans in Sydney
The Korean community in Sydney first became palpable in the early 1970s. The community has continued to expand in numbers and nature. This is reflected by various structures around which the Korean community in Sydney is organised. Notable organisations include over 150 Koreanlanguage Christian church congregations, multifarious business enterprises, and an established Korean language text and broadcast media which includes both local and imported materials and information
Calculated Nationalism in Contemporary South Korea
Nationalism in a nation-state reflects its emergent structural, cultural, and personal properties at a given time. In the politico-historical context of South Korea and the globe, the fruits of the 1968 Revolution in France could not reach Korean society under its military regime and exploitative economic structure. This continued to frustrate the grassroots and especially social actors in South Korea, which eventually brought about the June Struggle in 1987 and the 2016–2017 Candlelight Revolution. Calculated Nationalism in Contemporary South Korea sketches Korean grassroots’ perception of their nation-state, national identities, and what they desire regarding the future direction of their nation-state. The grassroots have openly spoken out about their frustrations through political rallies and media. This book attempts to reflect the minds of Korean progressives regarding, in particular, the forcibly recruited Japanese military “comfort women,” Abe’s trade provocation against South Korea in 2019, reunification, the 2016–2017 Candlelight Revolution, National Flag-carriers’ struggles, and bullying at work
A review of metal foam and metal matrix composites for heat exchangers and heat Sinks
Recent advances in manufacturing methods open the possibility for broader use of metal foams and metal matrix composites (MMCs) for heat exchangers, and these materials can have tailored material properties. Metal foams in particular combine a number of interesting properties from a heat exchanger's point of view. In this paper, the material properties of metal foams and MMCs are surveyed, and the current state of the art is reviewed for heat exchanger applications. Four different applications are considered: liquid-liquid, liquid-gas, and gas-gas heat exchangers and heat sinks. Manufacturing and implementation issues are identified and discussed, and it is concluded that these materials hold promise both for heat exchangers and heat sinks, but that some key issues still need to be solved before broad-scale application is possible
Gene Family Evolution across 12 Drosophila Genomes
Comparison of whole genomes has revealed large and frequent changes in the size of gene families. These changes occur because of high rates of both gene gain (via duplication) and loss (via deletion or pseudogenization), as well as the evolution of entirely new genes. Here we use the genomes of 12 fully sequenced Drosophila species to study the gain and loss of genes at unprecedented resolution. We find large numbers of both gains and losses, with over 40% of all gene families differing in size among the Drosophila. Approximately 17 genes are estimated to be duplicated and fixed in a genome every million years, a rate on par with that previously found in both yeast and mammals. We find many instances of extreme expansions or contractions in the size of gene families, including the expansion of several sex- and spermatogenesis-related families in D. melanogaster that also evolve under positive selection at the nucleotide level. Newly evolved gene families in our dataset are associated with a class of testes-expressed genes known to have evolved de novo in a number of cases. Gene family comparisons also allow us to identify a number of annotated D. melanogaster genes that are unlikely to encode functional proteins, as well as to identify dozens of previously unannotated D. melanogaster genes with conserved homologs in the other Drosophila. Taken together, our results demonstrate that the apparent stasis in total gene number among species has masked rapid turnover in individual gene gain and loss. It is likely that this genomic revolving door has played a large role in shaping the morphological, physiological, and metabolic differences among species
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