http://rose.bris.ac.uk:80 The ROSE digital repository system captures, stores, indexes, preserves, and distributes digital research material. 2013-05-13T09:18:59Z http://hdl.handle.net/1983/1834 Phonological memory, attention control, and musical ability: effects of individual differences on rater judgments of second language speech Isaacs, T; Trofimovich, Pavel This study examines how listener judgments of second language speech relate to individual differences in listeners’ phonological memory, attention control, and musical ability. Sixty native English listeners (30 music majors, 30 nonmusic majors) rated 40 nonnative speech samples for accentedness, comprehensibility, and fluency. The listeners were also assessed for phonological memory (serial recognition), attention control (trail making), and musical aptitude. Results showed that music majors assigned significantly lower scores than nonmusic majors solely for accentedness, particularly for low ability second language speakers. However, the ratings were not significantly affected by individual differences in listeners’ phonological memory and attention control, which implies that these factors do not bias listeners’ subjective judgments of speech. Implications for psycholinguistic research and for high-stakes speaking assessments are discussed. 2011-01-01T00:00:00Z http://hdl.handle.net/1983/1833 Primitive roles for inhibitory interneurons in developing frog spinal cord Li, W-C; Higashijima, Shin-ich; Parry, DM; Roberts, A; Soffe, SR Understanding the neuronal networks in the mammal spinal cord is hampered by the diversity of neurons and their connections. The simpler networks in developing lower vertebrates may offer insights into basic organization. To investigate the function of spinal inhibitory interneurons in Xenopus tadpoles, paired whole-cell recordings were used.We show directly that one class of interneuron, with distinctive anatomy, produces lycinergic, negative feedback inhibition that can limit firing in motoneurons and interneurons of the central pattern generator during swimming. These same neurons also produce inhibitory gating of sensory pathways during swimming. This discovery raises the possibility that some classes of interneuron, with distinct functions later in development, may differentiate from an earlier class in which these functions are shared. Preliminary evidence suggests that these inhibitory interneurons express the transcription factor engrailed, supporting a probable homology with interneurons in developing zebrafish that also express engrailed and have very similar anatomy and functions. 2004-01-01T00:00:00Z http://hdl.handle.net/1983/1832 Location-aided multi-user beamforming for 60 GHz WPAN systems Zhu, X; Doufexi, A; Kocak, T 60 GHz wireless personal area networks (WPANs) offer multi-Gbps throughput, which will provide for a new wave of high data rate applications. This paper exploits the use of location information to improve the performance and enhance range of 60 GHz multi-user beamforming systems. When the location information is available at the transmitter, the scheduler chooses a set of maximum angularly separated users to share wireless resources simultaneously. If additional feedback of signal-to-interference and noise ratio (SINR) is known, a location-assisted scheduler is employed to increase the system overall performance. Both numerical and simulated results show that significant enhancement can be achieved by the proposed schedulers for 60 GHz WPAN systems. 2012-05-01T00:00:00Z http://hdl.handle.net/1983/1831 CARLA: combining Cooperative Relaying and Link Adaptation for IEEE 802.11 wireless networks Li, L; Zhong, Fan; Kaleshi, D In this paper, we present a novel design named CARLA which combines Cooperative Relaying and Link Adaptation for IEEE 802.11 wireless networks, in order to maximize spectral efficiency and hence improve the throughput of the network. Unlike previous studies assuming that accurate channel information is available for relaying and link adaptation,the novelty of our approach is to use the expected packet transmission time (ETT) and RTS/CTS exchange to estimate the quality and level of contention for the current channel. By taking into account the quality of the direct channel from source to destination and the relay channel between relay and destination, CARLA enables both source and relay terminals to adjust their transmission rates so that not only the reliability of the transmission but also the bandwidth efficiency can be improved, hence fully utilizing the diversity gain. CARLA is a simple, distributed and rate-per-link adaptation protocol requiring no modification on 802.11 PHY and MAC. Simulation results show that CARLA can achieve significant performance improvement in terms of end-to-end throughput and energy efficiency for different network conditions. 2012-05-01T00:00:00Z