Spatial Diffuseness Features for DNN-Based Speech Recognition in Noisy and Reverberant Environments

We propose a spatial diffuseness feature for deep neural network (DNN)-based automatic speech recognition to improve recognition accuracy in reverberant and noisy environments. The feature is computed in real-time from multiple microphone signals without requiring knowledge or estimation of the direction of arrival, and represents the relative amount of diffuse noise in each time and frequency bin. It is shown that using the diffuseness feature as an additional input to a DNN-based acoustic model leads to a reduced word error rate for the REVERB challenge corpus, both compared to logmelspec features extracted from noisy signals, and features enhanced by spectral subtraction.Comment: accepted for ICASSP201

Algebraic structures on parallel M2-branes

In the course of closing supersymmetry on parallel M2 branes up to a gauge transformation, following the suggestion in hep-th/0611108 of incorporating a gauge field which only has topological degrees of freedom, we are led to assume a certain algebraic structure for the low energy theory supposedly living on parallel M2 branes.Comment: 13 pages; v4: complete on-shell closure of supersymmetry, abstract changed, v5: gauge transformations are carefully define

On Threefold Revelation of God

The most important thing that distinguishes leaders from nonleaders is that leaders are responsible for other people. Leaders cannot afford to limit their focus to themselves and their own favorite theologies shaped by their biographies, including both highly personal traumata and eureka experiences. they must be able to serve people according to the spiritual needs of these people, which should not be confused with the spiritual needs that the leader may have himself or herself. People without leadership responsibility are free to simply project their own spiritual experiences on others; for a leader, this would be highly immature, even irresponsible. If we approach the Triune God as we try to do through the Trinitarian Compass, we have a way of assessing the spiritual needs of the people we are responsible for, and to address these needs in a fruitful way. We also have a way of monitoring the progress that people make in their endeavor to radiate increasingly all the colors of light through their own lives. And the same dynamics that apply to the lives of other people apply to the lives of the leaders themselves. the Trinitarian Compass helps them to radiate god’s power, wisdom, and love, better than before

Neutron-star merger ejecta as obstacles to neutrino-powered jets of gamma-ray bursts

We present the first special relativistic, axisymmetric hydrodynamic simulations of black hole-torus systems (approximating general relativistic gravity) as remnants of binary-neutron star (NS-NS) and neutron star-black hole (NS-BH) mergers, in which the viscously driven evolution of the accretion torus is followed with self-consistent energy-dependent neutrino transport and the interaction with the cloud of dynamical ejecta expelled during the NS-NS merging is taken into account. The modeled torus masses, BH masses and spins, and the ejecta masses, velocities, and spatial distributions are adopted from relativistic merger simulations. We find that energy deposition by neutrino annihilation can accelerate outflows with initially high Lorentz factors along polar low-density funnels, but only in mergers with extremely low baryon pollution in the polar regions. NS-BH mergers, where polar mass ejection during the merging phase is absent, provide sufficiently baryon-poor environments to enable neutrino-powered, ultrarelativistic jets with terminal Lorentz factors above 100 and considerable dynamical collimation, favoring short gamma-ray bursts (sGRBs), although their typical energies and durations might be too small to explain the majority of events. In the case of NS-NS mergers, however, neutrino emission of the accreting and viscously spreading torus is too short and too weak to yield enough energy for the outflows to break out from the surrounding ejecta shell as highly relativistic jets. We conclude that neutrino annihilation alone cannot power sGRBs from NS-NS mergers.Comment: 7 pages, 4 figures, minor revisions compared to original version, accepted for publication in ApJ Letter