Evaluating cross-linguistic forced alignment of conversational data in north Australian Kriol, an under-resourced language

Speech technology is transforming language documentation; acoustic models trained on “small” languages are now technically feasible. At the same time, forced alignment built for major world languages has matured and now offers ease of use through web interfaces requiring low technical expertise. This paper provides an updated and detailed evaluation of cross-linguistic forced alignment, the approach of using forced aligners untrained on the target language. We compare two options within MAUS (Munich Automatic Segmentation System): language-independent mode vs major world language system (here, Italian) on the one dataset, a comparison that has not previously been reported. The dataset comes from a corpus of adult conversational speech in Kriol, an English-based creole of northern Australia. The results of using MAUS Italian were better than those of using the language-independent mode and those in previous studies: the agreement rate at 20 ms was 72.1% at vowel onset and 57.2% at vowel offset. With completely misaligned tokens excluded, the overall agreement rate rose to 69.2% at 20 ms and over 90% at 50 ms. Most errors in the output SAMPA (Speech Assessment Methods Phonetic Alphabet) labels were resolvable with simple text replacements. These results offer updated benchmark data for an untrained, late-model forced alignment system.National Foreign Language Resource Cente

Performance Evaluation for Subarray-based Reconfigurable Intelligent Surface-Aided Wireless Communication Systems

Reconfigurable intelligent surfaces (RISs) have received extensive concern to improve the performance of wireless communication systems. In this paper, a subarray-based scheme is investigated in terms of its effects on ergodic spectral efficiency (SE) and energy efficiency (EE) in RIS-assisted systems. In this scheme, the adjacent elements divided into a subarray are controlled by one signal and share the same reflection coefficient. An upper bound of ergodic SE is derived and an optimal phase shift design is proposed for the subarray-based RIS. Based on the upper bound and optimal design, we obtain the maximum of the upper bound. In particular, we analytically evaluate the effect of the subarray-based RIS on EE since it reduces SE and power consumption simultaneously. Numerical results verify the tightness of the upper bound, demonstrate the effectiveness of the optimal phase shift design for the subarray-based RIS, and reveal the effects of the subarray-based scheme on SE and EE.Comment: 6 pages, 4 figures, accepted by IEEE GLOBECOM 202

The mechanism producing initial transients on the clarinet

In self-sustained instruments, starting transients are important timbral characteristics that help identify the instrument and the playing style. Often, the oscillation starts as a growing exponential. This study investigates the starting amplitude of this exponential for the clarinet. After a rapid tongue release, the reed quickly returns to its equilibrium position. The sudden change in aperture produces an abrupt change in both the airflow into the mouthpiece and the mouthpiece pressure. This perturbation travels along the bore and reflects at the open end. Returning to the mouthpiece with slight attenuation, the perturbation can be amplified by the reed acting as an active element - effectively a negative resistance. When the reed release time exceeds the time for sound to travel twice the bore length, the airflow and pressure wave into the bore via the aperture are superposed over their own returning reflection. Measurements of reed motion and mouthpiece pressures during reed release yield values that are used in a model to calculate waveforms showing similarities to those observed experimentally. The initial amplitude decreases with increasing reed release time, though not always monotonically. It can become very small in special cases due to synchronisation between the initial pulse and its reflection

Editorial: CO 2 -based energy systems for cooling, heating, and power

© 2022 Li, Su, Xu, Dai, Li and Li. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). https://creativecommons.org/licenses/by/4.0/Peer reviewe