747 resultados para Sounds.


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Humpback whale ‘‘social sounds’’ appear to be used in communication when whales interact but they have received little study in comparison to the song. During experiments as part of the Humpback whale Acoustics Research Collaboration (HARC), whales migrating past the study site on the east coast of Australia produced a wide range of social sounds. Whales were tracked visually using a theodolite and singers were tracked acoustically using an array of five widely spaced hydrophones. Source levels of social sounds were calculated from the received level of the sounds, corrected for measured propagation loss. Playbacks of social sounds were made using a J11 transducer and the consequent reactions were recorded in terms of the change in direction of the migrating whales in relation to the playback position. In one playback, a DTAG was place on a female with calf. Playback of social sounds resulted in significant changes in the course of the migrating whales, in some cases towards the transducer while in others it was away from the transducer. From the estimates of source levels it is possible to assess the effectiveness of the playback and the range of influence of social sounds. [Work supported by ONR and DSTO.]

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DUE TO COPYRIGHT RESTRICTIONS ONLY AVAILABLE FOR CONSULTATION AT ASTON UNIVERSITY LIBRARY AND INFORMATION SERVICES WITH PRIOR ARRANGEMENT

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Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution. ^

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The present study investigated the development of sensitivity to temporal synchrony between sounds of impact and pauses in the movement of an object by infants of 2 1/2, 4 and 6 months of age. Ninety infants were tested across four experiments with side-by-side videos of a red and white square and a blue and yellow triangle along with a centralized soundtrack which was synchronized with only one of the films. This preference phase was then followed by a search phase, where the two films were accompanied by intermittent bursts of the soundtrack from each object. Twomonth- olds showed no evidence of matching films and soundtracks on the basis of synchrony, however 4-month-olds looked more on the second block of trials to the object which paused when the sound occurred and directed more first looks during the preference phase to the matching object. Six-month-olds demonstrated significantly more first looks to the mismatched object during the search phase only. These results suggest that infants relate impact sounds with synchronous pauses in continuous motion by the age of four months.

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Cetaceans are aquatic mammals that rely primarily on sound for most daily tasks. A compendium of sounds is emitted for orientation, prey detection, and predator avoidance, and to communicate. Communicative sounds are among the most studied Cetacean signals, particularly those referred to as tonal sounds. Because tonal sounds have been studied especially well in social dolphins, it has been assumed these sounds evolved as a social adaptation. However, whistles have been reported in ‘solitary’ species and have been secondarily lost three times in social lineages. Clearly, therefore, it is necessary to examine closely the association, if any, between whistles and sociality instead of merely assuming it. Several hypotheses have been proposed to explain the evolutionary history of Cetacean tonal sounds. The main goal of this dissertation is to cast light on the evolutionary history of tonal sounds by testing these hypotheses by combining comparative phylogenetic and field methods. This dissertation provides the first species-level phylogeny of Cetacea and phylogenetic tests of evolutionary hypotheses of cetacean communicative signals. Tonal sounds evolution is complex in that has likely been shaped by a combination of factors that may influence different aspects of their acoustical structure. At the inter-specific level, these results suggest that only tonal sound minimum frequency is constrained by body size. Group size also influences tonal sound minimum frequency. Species that live in large groups tend to produce higher frequency tonal sounds. The evolutionary history of tonal sounds and sociality may be intertwined, but in a complex manner rejecting simplistic views such as the hypothesis that tonal sounds evolved ‘for’ social communication in dolphins. Levels of social and tonal sound complexity nevertheless correlate indicating the importance of tonal sounds in social communication. At the intraspecific level, tonal sound variation in frequency and temporal parameters may be product of genetic isolation and local levels of underwater noise. This dissertation provides one of the first insights into the evolution of Cetacean tonal sounds in a phylogenetic context, and points out key species where future studies would be valuable to enrich our understanding of other factors also playing a role in tonal sound evolution.

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Aims and Scope: No sound class requires so much basic knowledge of phonology, acoustics, aerodynamics, and speech production as obstruents (turbulent sounds) do. This book is intended to bridge a gap by introducing the reader to the world of obstruents from a multidisciplinary perspective. It starts with a review of typological processes, continues with various contributions to the phonetics-phonology interface, explains the realization of specific turbulent sounds in endangered languages, and finishes with surveys of obstruents from a sociophonetic, physical and pathological perspective.

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Research in various fields has shown that students benefit from teacher action demonstrations during instruction, establishing the need to better understand the effectiveness of different demonstration types across student proficiency levels. This study centres upon a piano learning and teaching environment in which beginners and intermediate piano students (N=48) learning to perform a specific type of staccato were submitted to three different (group exclusive) teaching conditions: audio-only demonstration of the musical task; observation of the teacher's action demonstration followed by student imitation (blockedobservation); and observation of the teacher's action demonstration whilst alternating imitation of the task with the teacher's performance (interleaved-observation). Learning was measured in relation to students' range of wrist amplitude (RWA) and ratio of sound and inter-sound duration (SIDR) before, during and after training. Observation and imitation of the teacher’s action demonstrations had a beneficial effect on students' staccato knowledge retention at different times after training: students submitted to interleaved-observation presented significantly shorter note duration and larger wrist rotation, and as such, were more proficient at the learned technique in each of the lesson and retention tests than students in the other learning conditions. There were no significant differences in performance or retention for students of different proficiency levels. These findings have relevant implications for instrumental music pedagogy and other contexts where embodied action is an essential aspect of the learning process.

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The MARS (Media Asset Retrieval System) Project is the collaborative effort of public broadcasters,libraries and schools in the Puget Sound region to create a digital online resource that provides access to content produced by public broadcasters via the public libraries. Convergence ConsortiumThe Convergence Consortium is a model for community collaboration, including organizations such as public broadcasters, libraries, museums, and schools in the Puget Sound region to assess the needs of their constituents and pool resources to develop solutions to meet those needs. Specifically, the archives of public broadcasters have been identified as significant resources for the local communities and nationally. These resources can be accessed on the broadcasters websites, and through libraries and used by schools, and integrated with text and photographic archives from other partners.MARS’ goalCreate an online resource that provides effective access to the content produced locally by KCTS (Seattle PBS affiliate) and KUOW (Seattle NPR affiliate). The broadcasts will be made searchable using the CPB Metadata Element Set (under development) and controlled vocabularies (to be developed). This will ensure a user friendly search and navigation mechanism and user satisfaction.Furthermore, the resource can search the local public library’s catalog concurrently and provide the user with relevant TV material, radio material, and books on a given subject.The ultimate goal is to produce a model that can be used in cities around the country.The current phase of the project assesses the community’s need, analyzes the current operational systems, and makes recommendations for the design of the resource.Deliverables• Literature review of the issues surrounding the organization, description and representation of media assets• Needs assessment report of internal and external stakeholders• Profile of the systems in the area of managing and organizing media assetsfor public broadcasting nationwideActivities• Analysis of information seeking behavior• Analysis of collaboration within the respective organizations• Analysis of the scope and context of the proposed system• Examining the availability of information resources and exchangeof resources among users

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The MARS (Media Asset Retrieval System) Project is a collaboration between public broadcasters, libraries and schools in the Puget Sound region to assess the needs of their constituents and pool resources to develop solutions to meet those needs. The Project’s ultimate goal is to create a digital online resource that will provide access to content produced by public broadcasters and libraries. The MARS Project is funded by a grant from the Corporation for Public Broadcasting (CPB) Television Future Fund. Convergence ConsortiumThe Convergence Consortium is a model for community collaboration, including representatives from public broadcasting, libraries and schools in the Puget Sound region. They meet regularly to consider collaborative efforts that will be mutually beneficial to their institutions and constituents. Specifically, the archives of public broadcasters have been identified as significant resources that can be accessed through libraries and used by schools, and integrated with text and photographic archives from other partners.Using the work-centered framework, we collected data through interviews with nine engineers and observation of their searching while they performed their regular, job-related searches on the Web. The framework was used to analyze the data on two levels: 1) the activities and organizational relationships and constrains of work domains, and 2) users’ cognitive and social activities and their subjective preferences during searching.