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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Acoustic Tonal and Vector Properties of Red Hind Grouper Vocalizationd

Unknown Date (has links)
Vertebrates are the most prodigious vocalizing animals in existence, and the most diverse methods of acoustic communication among vertebrates can be found in the ocean. Relatively many teleost fish are gifted with the ability to communicate acoustically, and the family of serranidae often performs this as a function of the swim bladder. Epinephelus Guttatus (E. guttatus), or more commonly the red hind grouper, is equipped with a drum shaped swim bladder acting as a monopole under typical ocean conditions. This configuration allows for what is understood to be omnidirectional projection of tones approximately centered between 40 and 440 Hz and spanning anywhere from 40 to 200 Hz of bandwidth and modulation effects based on observed data provided by researchers. Prior studies on many other fish show correlation in acoustic communication profile with length, size and sexual identity. In the red hind, sexual dimorphism leads to an inherent female identity in all juvenile fish which converts to male according to environmental factors, recommending at least consistent organs across both sexes be assumed even if not in use. Much research has been performed on male fish vocalization in terms of spectral content. Communication in fish is a complex multi-modal process, with acoustic communication being important for many of the species, particularly those in the littoral regions of the worlds’ oceans. If identifying characteristics of the red hind vocalization can be isolated based on detection, classification, tracking and localizing methodologies, then these identifying characteristics may indeed lead to passive feature identification that allows for estimation of individual fish mass. Hypotheses based on vector, cyclostationary and classical tonal mechanics are presented for consideration. A battery of test data collection events, applying pre-recorded fish vocalizations to a geolocated undersea sound source were conducted. The results are supplied with the intent of validating hypothesis in a non-expert system manner that shows how a series of biological metrics may be assessed for detection, classification, localization and mass estimation for an individual vocalizing red hind grouper / Includes bibliography. / Dissertation (Ph.D.)--Florida Atlantic University, 2017. / FAU Electronic Theses and Dissertations Collection
32

Avian musing feature space analysis

Colón, Guillermo J. 24 May 2012 (has links)
The purpose of this study was to analyze the possibility of utilizing known signal processing and machine learning algorithms to correlate environmental data to chicken vocalizations. The specific musing to be analyzed consist of not just one chicken's vocalizations but of a whole collective, it therefore becomes a chatter problem. There have been similar attempts to create such a correlation in the past but with singled out birds instead of a multitude. This study was performed on broiler chickens (birds used in meat production). One of the reasons why this correlation is useful is for the purpose of an automated control system. Utilizing the chickens own vocalization to determine the temperature, the humidity, the levels of ammonia among other environmental factors, reduces, and might even remove, the need for sophisticated sensors. Another factor that this study wanted to correlate was stress in the chickens to their vocalization. This has great implications in animal welfare, to guarantee that the animals are being properly take care off. Also, it has been shown that the meat of non-stressed chickens is of much better quality than the opposite. The audio was filtered and certain features were extracted to predict stress. The features considered were loudness, spectral centroid, spectral sparsity, temporal sparsity, transient index, temporal average, temporal standard deviation, temporal skewness, and temporal kurtosis. In the end, out of all the features analyzed it was shown that the kurtosis and loudness proved to be the best features for identifying stressed birds in audio.
33

Variation in sperm whale (Physeter macrocephalus) coda vocalizations and social structure in the North Atlantic Ocean

Antunes, Ricardo January 2009 (has links)
This study aimed at complementing studies of sperm whale social and vocal behaviour that were restricted to the Pacific Ocean. The characteristic multi-pulsed structure of sperm whale clicks allows for estimation of whales' size from measurements of the inter-pulse intervals (IPI). I have developed two new automatic methods for IPI estimation from clicks recorded during foraging dives. When compared to other previously developed methods, the newly developed method that averages several clicks' autocorrelation function showed the best performance amongst the automatic methods. Previous studies did not support individual identity advertisement among social unit members as the function for the sperm whale communication signals called codas. I tested within coda type variation for individual specific patterns and found that, while some coda types do not allow for individual discrimination, one did so. This variation suggests that different coda types may have distinct functions. Analysis of social structure in the Azores found that, similar to the Eastern Tropical Pacific, sperm whales form long term social units of about 12 individuals. Unlike the Pacific Ocean, Azorean social units do not form temporary groups with other units, suggesting differences in the costs and benefits of group formation. I argue that these are due to differences in terms of predation pressure and intraspecific competition between the Azores and the Pacific study sites. The variation of coda repertoires in the Atlantic also showed a pattern dissimilar to that previously documented in the Eastern Tropical Pacific. In the North Atlantic, coda repertoire variation is mostly geographic, which is parsimoniously explained by random drift of culturally transmitted coda repertoires. No sympatric vocal clans with distinct dialects were found as has been noted in the Pacific. Drawing upon the differences found in social structure I argue that selection for maximization of differences between units with similar foraging strategies may have led to the Pacific vocal clans. The differences between oceans suggest that sperm whales may adaptively adjust their behaviour according to experienced ecological conditions.
34

Cultura material e ressignificação do simbólico sagrado: rupturas e permanências através da percepção sonora

Sousa, Ana Maria da Silva Gomes de Oliveira Lucio de 21 February 2018 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2018-03-16T12:13:18Z No. of bitstreams: 1 Ana Maria da Silva Gomes de Oliveira Lucio de Sousa.pdf: 6698738 bytes, checksum: f2df6c7f902a953a277d0ff45dac6e5a (MD5) / Made available in DSpace on 2018-03-16T12:13:18Z (GMT). No. of bitstreams: 1 Ana Maria da Silva Gomes de Oliveira Lucio de Sousa.pdf: 6698738 bytes, checksum: f2df6c7f902a953a277d0ff45dac6e5a (MD5) Previous issue date: 2018-02-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / This work has two main aims. The first consists in the intention of contributing to the studies concerning the relationship between mankind and sound production, in order to favour the theoretical and methodologic process of construction in the field of Archaeology. The second aim is to use that to answer certain questions related to the desacralization process of the modern world in Western societies.During the postgraduate course in Archaeology, in the module on the ancient Roman world, the initial idea appeared as the theoretical and methodologic difficulties to study sound productions and their relation with men and society, in that period and in ancient contexts, was dealt with.Nowadays, new possibilities to make analyses on such questions are approached in the area of recent organological studies, in the field that belongs to Archaeomusicology and to the area of Experimental Archaeology, for studies related to the production of musical instruments based on archaeological and textual sources. Recently, the field of Ethnoarchaeomusicology has flourished as an important tool under development. I search, in this sense, to develop a study to analyse the relationship between men and sound production in the field of study of Brazilian Historical Archaeology; to that aim, sound artefacts related to the cultural tradition of communities were chosen. With that intent, three artefacts were selected: the Ika flute, used by the Bororo ethnic group; the Adjá, employed in rituals belonging to religions of African roots; and the Shepherd Rattle, used by the herdsman in the Northeast of Brazil.The three artefacts are related to contexts that carry the dimensions of the social and cosmological role of the sound they produce, and this fact qualifies them to the second purpose of this study, which is investigate the desacralization order that manifests itself in the contemporary world.I decided for the shepherd rattle, firstly by observing the peculiarities about such artefact, and secondly because of my previous contact with individuals from communities linked to cattle raising during a period of approximately ten years, between 1985 and 1995, when I settled down and worked as a teacher in the municipality of Patos, in the agreste region of the State of Paraíba.The established theoretical and methodological route was intended to meet four questionswhich were held as the main lines: the social reproduction behaviour related to the sound production of the artefact; the production processes subjected to interference; the relation between this sound production and the dimensions of the sacred and the artefact itself. In this trajectory, a interdisciplinary dialogue was developed, situating research fields from the disciplines of History, Anthropology, Ethnology, Brazilian Historic Archaeology, Organology and Acoustics in order to obtain substantial information and answer to the initially proposed questions / Este trabalho possui dois objetivos principais. O primeiro consiste na intenção de contribuir para os estudos que abordam a relação entre o homem e a produção de sons, para favorecer o processo de construção teórico e metodológico, no campo da Arqueologia. O segundo propósito é utilizar esta proposta para responder determinadas questões que estão relacionadas ao processo de dessacralização do mundo moderno, nas sociedades ocidentais.Durante o curso de Pós-Graduação em Arqueologia, na disciplina que trata do mundo romano antigo, surgiu aideia inicial, ao ter contato com as dificuldades teóricas e metodológicas para o estudo sobre as produções sonoras e a sua relação com o homem e a sociedade, naquele período e em contextos remotos. Atualmente, novas possibilidades de análise sobre estas questões são abordadas no campo de estudos organológicos recentes, no campo que pertence à Arqueomusicologia e ao campo da Arqueologia Experimental, para estudos relacionados à produção de instrumentos musicais com base em fontes arqueológicas e escritas. Recentemente, o campo da Etnoarqueomusicologia vem despontando como uma importante ferramenta em desenvolvimento.Busco, neste sentido, desenvolver um estudo para analisar a relação do homem com a produção de sons, no campo de estudo da Arqueologia Histórica Brasileira, tomando para tanto, um artefato sonoro relacionado à tradição cultural de uma comunidade. Para tanto, três artefatos foram selecionados: a flauta Ika utilizada pela etnia Bororo, o adjá utilizado nos rituais de religiões de matriz africana e o chocalho pastoril utilizado pelo vaqueiro no nordeste brasileiro.Os três artefatos estão relacionados a contextos que portam dimensões do papel social e cosmológico do som que produzem e este fato os qualificava para o segundo propósito deste estudo, qual seja, investigar a ordem de dessacralização que se manifesta no mundo contemporâneo. Decidi pelo chocalho pastoril, primeiro por observar as peculiaridades que envolvem este artefato e em segundo pelo meu contado anterior com representantes das comunidades ligadas à pecuária, no período de aproximadamente dez anos, entre 1985 e 1995, quando me estabeleci e atuei no trabalho docente, no município de Patos, no agreste do estado da Paraíba.O caminho teórico e metodológico estabelecido procurou se alinhar a quatro questões que foram mantidas como principais vetores: o comportamento de reprodução social relacionado à produção sonora do artefato, os processos produtivos nos quais interferiram, a relação entre esta produção sonora e as dimensões do sagrado e o artefato em si. Neste percurso,o diálogo interdisciplinar foi desenvolvido, situando campos investigativos originários da História, Antropologia, Etnologia, Arqueologia Histórica Brasileira, Organologia, e Acústica, para obter informações substanciais e responder os questionamentos propostos inicialmente
35

Social contagion in common marmosets (Callithrix jacchus) : implications for cognition, culture and welfare

Watson, Claire F. I. January 2011 (has links)
The social transmission of social behaviours in nonhuman primates has been understudied, experimentally, relative to instrumental, food-related behaviours. This is disproportional in relation to the comparatively high percentage of potential social traditions reported in wild primates. I report a systematic survey of the social learning literature and provide quantitative evidence of the discrepancy (Watson and Caldwell, 2009). Addressing the identified deficit in experimental work on social behaviours, I also report three empirical studies investigating the contagious nature of affective states in captive, socially housed marmosets. I carried out an observational study, to determine whether marmosets are influenced by spontaneously produced neighbour calls to perform a range of behaviours associated with similar affect. My results supported a neighbour effect for anxiety in marmosets. Consistent with previous findings for chimpanzees (Baker and Aureli, 1996; Videan et al., 2005), I also found evidence for neighbour effects for aggression and affiliation (Watson and Caldwell, 2010). Through experimental playback, I investigated contingent social contagion in the auditory and visual modalities. The playback of pre-recorded affiliative (chirp) calls was found to be associated with marmosets spending increased time in a range of affiliative behaviours. Playback of video showing conspecifics engaged in a positive affiliative behaviour (allogrooming) also appeared to cause marmosets to spend longer performing various affiliative behaviours. My results indicate that social contagion of affiliation is a multi-modal phenomenon in marmosets and also represent the first evidence that allogrooming is visually contagious in primates. Sapolsky (2006) conceptualised culture as the performance of species-typical behaviours to an unusual extent, termed ‘social culture’. Researchers have yet to directly investigate a transmission mechanism. I investigated whether a social culture of increased affiliation could be initiated in marmosets through the long-term playback, of positive calls, or of video of positive behaviour. The results were consistent with a relatively long-lasting influence of the playback of affiliative calls across several affiliative behaviours. The effect appeared to last substantially beyond the specific hours of playback, between playbacks, and after playback had ceased, potentially indicating a temporary shift in social culture. These results are preliminary but provide some support for the proposal that auditory social contagion may be a transmission mechanism for social culture. The long-term video playback of allogrooming appeared to result in a transitory shift in performance of the identical behaviour (increased allogrooming) after playbacks had ceased. In addition to theoretical implications for social cognition and social culture, my findings have potential practical application for the enhancement of welfare in captive marmosets through sensory, and non-contact social, enrichment.

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