Arabic Language WEKA-Based Dialect Classifier for Arabic Automatic Speech Recognition Transcripts

This paper describes an Arabic dialect identification system which we developed for the Discriminating Similar Languages (DSL) 2016 shared task. We classified Arabic dialects by using Waikato Environment for Knowledge Analysis (WEKA) data analytic tool which contains many alternative filters and classifiers for machine learning. We experimented with several classifiers and the best accuracy was achieved using the Sequential Minimal Optimization (SMO) algorithm for training and testing process set to three different feature-sets for each testing process. Our approach achieved an accuracy equal to 42.85% which is considerably worse in comparison to the evaluation scores on the training set of 80-90% and with training set 60:40 percentage split which achieved accuracy around 50%. We observed that Buckwalter transcripts from the Saarland Automatic Speech Recognition (ASR) system are given without short vowels, though the Buckwalter system has notation for these. We elaborate such observations, describe our methods and analyse the training dataset

Ultra-low noise, bi-polar, programmable current sources

We present the design process and implementation of fully open-source, ultra-low noise programmable current source systems in two configurations. Although originally designed as coil drivers for Optically Pumped Magnetometers (OPMs), the device specifications make them potentially useful in a range of applications. The devices feature a bi-directional current range of $\pm$~10~mA and $\pm$~250~mA respectively on three independent channels with 16-bit resolution. Both devices feature narrow 1/f noise bandwidth of 1~Hz, enabling magnetic field manipulation for high-performance OPMs. They exhibit low noise of 146.3~pA/$\sqrt{\mathrm{Hz}}$ and 4114~pA/$\sqrt{\mathrm{Hz}}$ which translates to 14.57~ppb/$\sqrt{\mathrm{Hz}}$ and 16.46~ppb/$\sqrt{\mathrm{Hz}}$ noise relative to full scale.Comment: 9 pages, 9 figure

Predatory Organisms with Untapped Biosynthetic Potential:Descriptions of Novel Corallococcus Species C. aberystwythensis sp. nov., C. carmarthensis sp. nov., C. exercitus sp. nov., C. interemptor sp. nov., C. llansteffanensis sp. nov., C. praedator sp. nov., C. sicarius sp. nov., and C. terminator sp. nov

Corallococcus spp. are common soil-dwelling organisms which kill and consume prey microbes through the secretion of antimicrobial substances. Two species of Corallococcus have been described previously (Corallococcus coralloides and Corallococcus exiguus). A polyphasic approach was taken to characterise antimicrobial, biochemical and phenotypic properties of eight Corallococcus spp. strains and the two type strains. We also report here the genome sequence of the C. exiguus type strain (DSM 14696T). The genomes of the eight candidate strains, C. exiguus DSM 14696T and C. coralloides DSM 2259T, had an average nucleotide identity below 95% and digital DNA-DNA hybridisation scores less than the 70% lower bound for species identity, indicating they belong to distinct species. All ten strains, including the two type strains, were thoroughly characterised, including biochemical analysis of their fatty acid methyl esters, substrate utilisation and sugar assimilation. Each strain gave a distinct profile of properties, which together with their genomic differences supports the proposal of the eight candidate strains as novel species: Corallococcus exercitus sp. nov. (AB043AT = DSM 108849T = NBRC 113887T), Corallococcus interemptor sp. nov. (AB047AT = DSM 108843T = NBRC 113888T), Corallococcus aberystwythensis sp. nov. (AB050AT = DSM 108846T = NBRC 114019T), Corallococcus praedator sp. nov. (CA031BT = DSM 108841T = NBRC 113889T), Corallococcus sicarius sp. nov. (CA040BT = DSM 108850T = NBRC 113890T), Corallococcus carmarthenensis sp. nov. (CA043DT = DSM 108842T = NBRC 113891T), Corallococcus llansteffanensis sp. nov. (CA051BT = DSM 108844T = NBRC 114100T) and Corallococcus terminator sp. nov. (CA054AT = DSM 108848T = NBRC 113892T)

The Far-Ultraviolet "Continuum" in Protoplanetary Disk Systems II: CO Fourth Positive Emission and Absorption

We exploit the high sensitivity and moderate spectral resolution of the $HST$-Cosmic Origins Spectrograph to detect far-ultraviolet spectral features of carbon monoxide (CO) present in the inner regions of protoplanetary disks for the first time. We present spectra of the classical T Tauri stars HN Tau, RECX-11, and V4046 Sgr, representative of a range of CO radiative processes. HN Tau shows CO bands in absorption against the accretion continuum. We measure a CO column density and rotational excitation temperature of N(CO) = 2 +/- 1 $\times$ 10$^{17}$ cm$^{-2}$ and T_rot(CO) 500 +/- 200 K for the absorbing gas. We also detect CO A-X band emission in RECX-11 and V4046 Sgr, excited by ultraviolet line photons, predominantly HI LyA. All three objects show emission from CO bands at $\lambda$ $>$ 1560 \AA, which may be excited by a combination of UV photons and collisions with non-thermal electrons. In previous observations these emission processes were not accounted for due to blending with emission from the accretion shock, collisionally excited H$_{2}$, and photo-excited H2; all of which appeared as a "continuum" whose components could not be separated. The CO emission spectrum is strongly dependent upon the shape of the incident stellar LyA emission profile. We find CO parameters in the range: N(CO) 10$^{18-19}$ cm$^{-2}$, T_{rot}(CO) > 300 K for the LyA-pumped emission. We combine these results with recent work on photo- and collisionally-excited H$_{2}$ emission, concluding that the observations of ultraviolet-emitting CO and H2 are consistent with a common spatial origin. We suggest that the CO/H2 ratio in the inner disk is ~1, a transition between the much lower interstellar value and the higher value observed in solar system comets today, a result that will require future observational and theoretical study to confirm.Comment: 12 pages, 7 figures, 3 tables. ApJ - accepte

Ensemble prediction for nowcasting with a convection-permitting model - II: forecast error statistics

A 24-member ensemble of 1-h high-resolution forecasts over the Southern United Kingdom is used to study short-range forecast error statistics. The initial conditions are found from perturbations from an ensemble transform Kalman filter. Forecasts from this system are assumed to lie within the bounds of forecast error of an operational forecast system. Although noisy, this system is capable of producing physically reasonable statistics which are analysed and compared to statistics implied from a variational assimilation system. The variances for temperature errors for instance show structures that reflect convective activity. Some variables, notably potential temperature and specific humidity perturbations, have autocorrelation functions that deviate from 3-D isotropy at the convective-scale (horizontal scales less than 10 km). Other variables, notably the velocity potential for horizontal divergence perturbations, maintain 3-D isotropy at all scales. Geostrophic and hydrostatic balances are studied by examining correlations between terms in the divergence and vertical momentum equations respectively. Both balances are found to decay as the horizontal scale decreases. It is estimated that geostrophic balance becomes less important at scales smaller than 75 km, and hydrostatic balance becomes less important at scales smaller than 35 km, although more work is required to validate these findings. The implications of these results for high-resolution data assimilation are discussed