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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.
1

Bioacoustic techniques to monitor Great Gray Owls (Strix nebulosa) in the Sierra Nevada /

Rognan, Cameron B. January 1900 (has links)
Thesis (M.A.)--Humboldt State University, 2007. / Includes bibliographical references (leaves 60-64). Also available via Humboldt Digital Scholar.
2

Applications of bioacoustics to musical instrument technology : models for sound synthesis and musical controllers based on animal sound production mechanisms /

Smyth, Tamara. January 1900 (has links)
Thesis (Ph. D.)--Department of Music, Stanford University, 2004. / Includes bibliographical references (p. 127-134).
3

Monitoring Agroecosystem Biodiversity Using Bioacoustics and Remote Recording Units

Paisley-Jones, Claire E. 21 October 2011 (has links)
No description available.
4

Information in a long-distance vocal signal chorus howling in the coyote (Canis latrans) /

Hallberg, Karen Irene, January 2007 (has links)
Thesis (Ph. D.)--Ohio State University, 2007. / Title from first page of PDF file. Includes bibliographical references (p. 135-141).
5

Probabilistic models for classification of bioacoustic data

Lakshminarayanan, Balaji 30 December 2010 (has links)
Probabilistic models have been successfully applied for a wide variety of problems, such as but not limited to information retrieval, computer vision, bio-informatics and speech processing. Probabilistic models allow us to encode our assumptions about the data in an elegant fashion and enable us to perform machine learning tasks such as classification and clustering in a principled manner. Probabilistic models for bio-acoustic data help in identifying interesting patterns in the data (for instance, the species-specific vocabulary), as well as species identification (classification) in recordings where the label is not available. The focus of this thesis is to develop efficient inference techniques for existing models, as well as develop probabilistic models tailored to bioacoustic data. First, we develop inference algorithms for the supervised latent Dirichlet allocation (LDA) model. We present collapsed variational Bayes, collapsed Gibbs sampling and maximum-a-posteriori (MAP) inference for parameter estimation and classification in supervised LDA. We provide an empirical evaluation of the trade-off between computational complexity and classification performance of the inference methods for supervised LDA, on audio classification (species identification in this context)as well as image classification and document classification tasks. Next, we present novel probabilistic models for bird sound recordings, that can capture temporal structure at different hierarchical levels, and model additional information such as the duration and frequency of vocalizations. We present a non-parametric density estimation technique for parameter estimation and show that the MAP classifier for our models can be interpreted as a weighted nearest neighbor classifier. We provide an experimental comparison between the proposed models and a support vector machine based approach, using bird sound recordings from the Cornell Macaulay library. / Graduation date: 2011 / Access restricted to the OSU Community at author's request from Dec. 30, 2010 - Dec. 30, 2011
6

Potential for the Stimulation of Enodthelial Nitric Oxide Synthase Through the Use of Low Frequency Sound

May, Brandon H. 01 January 2006 (has links)
This study examines the possibility of the use of low frequency sound in the stimulation of Endothelial Nitric Oxide Synthase (eNOS), an enzyme which regulates the synthesis of NO from the amino acid L-arginine. To test this hypothesis, oximetry was used to measure changes in hemoglobin saturation in a subject exposed to a 45Hz signal, and accelerometers were used to monitor attenuation of two source frequencies (45Hz and 8Hz) across 5 subjects at varying source transducer locations. The data from the oximetry monitoring was only suggestive, but its interpretation is encouraging for future avenues of study. Examining the attenuation of the applied frequencies showed, as expected, did not show a strong dependence on the height or weight of the subject, with little transmission loss throughout the body. These data establish the firm groundwork for future experimentation to reduce the methodology into a clinically feasible medical device
7

Som de chamado, ultramorfologia da fileira estridulatória e morfologia do complexo fálico aplicados à taxonomia de Gryllus Linnaeus, 1758 do extremo sul do Rio Grande do Sul (Orthoptera, Gryllidae) /

Martins, Luciano de Pinho. January 2009 (has links)
Orientador: Edson Zefa / Banca: Maria Kátia Matiotti da Costa / Banca: Francisco de Assis Ganeo de Mello / Resumo: O gênero Gryllus Linnaeus, 1758 compreende 78 espécies descritas, ocorrendo na América desde o Canadá até a Argentina, bem como em diversas regiões da África, Europa e Ásia. Na América do Sul existem registros da ocorrência de 12 espécies que foram descritas no século XIX e desde então pouca informação foi adicionada à taxonomia desses insetos. Trata-se de um dos gêneros mais complexos de Grylloidea devido à presença de espécies crípticas e à taxonomia confusa, gerada por diferentes critérios taxonômicos e baseada em amostragens reduzidas, desprezando as variações intraespecíficas. O objetivo deste trabalho foi aplicar diversas ferramentas, com destaque à bioacústica e à morfologia da fileira estridulatória, retomando o trabalho taxonômico nos Gryllus da América do Sul, a partir de uma área restrita do extremo sul do Brasil. O trabalho foi dividido em três capítulos: I - Taxonomia de Gryllus Linnaeus, 1758 (Orthoptera, Gryllidae) do extremo sul do Brasil: duas novas espécies e Gryllus argentinus Saussure, 1874; II - Revisão do som de chamado e da fileira estridulatória de Gryllus Linnaeus, 1758 (Orthoptera, Gryllidae); III - Variação intraespecífica no som de chamado de Gryllus sp. n.2 (Orthoptera, Gryllidae): implicações taxonômicas. Os resultados deste trabalho servirão como base para os estudos taxonômicos em Gryllus na América do Sul e facilitarão as revisões do som de chamado e da fileira estridulatória neste gênero. A análise de proles provenientes de fêmeas fecundadas na natureza permitiu delimitar a variação no som de chamado de Gryllus sp. n.2, assegurando a determinação específica desse táxon. / Abstract: The genus Gryllus Linnaeus, 1758 includes 78 described species, occurring in America from Canada to Argentina, as well as in several areas of Africa, Europe and Asia. There are 12 species in South America described in nineteenth century. Since few data were added to the taxonomy of these insects. This genus is among the most complex of Grylloidea due cryptic species and ancient taxonomy erected by different criteria and based on small samples, despising intraspecific variations. The aim of this work was to apply tools such as bioacoustics and stridulatory file morphology, retaking the taxonomic study in South America's Gryllus, in a restricted area of Southern Brazil. The work was structured in three chapters: I - Taxonomy of Gryllus Linnaeus, 1758 (Orthoptera, Gryllidae) of the southern Brazil: two new species and Gryllus argentinus Saussure, 1874; II - Revision of the calling song and stridulatory file of Gryllus Linnaeus, 1758 (Orthoptera, Gryllidae); III - Intraespecific variation in the calling song of Gryllus n. sp.2 (Orthoptera, Gryllidae): taxonomic implications. This work presents information about calling song and stridilatory file features supporting new taxonomic studies on Gryllus. The offspring from field inseminated females confirmed that variations on the calling song of Gryllus n. sp.2 were intraspecific improving specific determination of this taxon. / Mestre
8

The use of automated acoustic identification software for bat surveys in the neotropics : Gaps and opportunities

Menon, Amrita Madhukumar January 2017 (has links)
As populações de morcegos são conhecidas por serem afetadas por atividades antropogênicas,njá que os Chiroptera é um grupo extremamente diverso que ocupa quase todos os nichos disponíveis no meio terrestre. Assim, os morcegos são considerados bons bioindicadores para monitorar mudanças no meio ambiente, mas seu valor como tal também depende da facilidade de monitorar e detectar tendências demográficas em suas populações. O interesse a longo prazo dos pesquisadores na acústica dos morcegos resulta do fato de que é um método não-invasivo e eficiente em termos de tempo para monitorar os padrões espaço-temporais da diversidade e atividade de morcegos. A análise dos sons emitidos pelos organismos tem sido útil para a aquisição de conhecimento sobre as interações bióticas e abióticas específicas de cada espécie, e sua aplicação na conservação. Além das identificações manuais de chamados de morcegos, existe atualmente no mercado um conjunto de programas automatizados de identificação que utilizam bibliotecas regionais e se apresentam como uma ferramenta eficiente no monitoramento de populações de morcegos. A maioria desses programas não foi validada usando dados de campo. Este estudo avalia a confiabilidade de dois softwares automatizados, SonoChiro e Kaleidoscope Pro, em comparação com identificações manuais de dados de campo coletados da região Neotropical. Houve um baixo nível de concordância entre os dois métodos automatizados ao nível das identificações específicas, razoável ao nível do gênero e satisfatório ao nível a família. Houve também uma diferença significativa entre a proporção de chamados corretamente identificados entre os dois programas ao nível específico. Os principais desafios para o uso de software de identificação automatizada incluem a necessidade de bibliotecas de chamados abrangentes da diversidade existente nas regiões em foco dos estudos; as principais oportunidades, por outro lado, incluem a ampla possibilidade de monitorar os padrões espaço-temporais da atividade de morcegos. Existem ainda fortes lacunas que impedem uma aplicação generalizada de programas automatizados em estudos ecológicos e de conservação de morcegos, mas há potencial de melhoria. Considerando as limitações dos programas automatizados, é discutida uma estrutura para aplicação em estudos ecológicos e de conservação. / Bat populations are known to be affected by anthropogenic activities because bats are an extremely diverse group occupying almost all available niches in terrestrial environment. Hence, bats are considered bioindicators to monitor changes in the environment, but their value as such also depends on the ease to monitor and detect demographic trends in their populations. The long term interest of researchers in the acoustic of bats results from the fact that it is a non-invasive, time-efficient methods to monitor spatiotemporal patterns of bat diversity and activity.The analysis of sounds emitted by organisms has been considered useful to gain insight into species-specific biotic and abiotic interactions, which can further be applied to conservation. Besides manual identifications of bat calls, a number of automated species identification programs using regional call classfiers have been introduced into the market as an efficient tool in monitoring of bat populations. Most of these programs have not been validated using field data. This study evaluates the reliability of two automated softwares, SonoChiro and Kaleidoscope Pro, in comparison to manual identifications of field data collected from the Neotropical region. There was low agreement between the two automated methods at the species level, fair agreement at the genus level and moderate agreement at the family level. There was also a significant difference between the proportion of correctly identified calls of the two-automated software at the species level identifications. Major challenges for using automated identification software include the need for comprehensive call libraries of the regions under scope; major opportunities, on the other hand, include the widespread possibility to monitor spatiotemporal patterns of bat activity. Overall, there are serious gaps that preclude a widespread application of automated programs in ecological and conservation studies of bats, but there is a potential for improvement. Considering the limitations of the automated programs, a framework for application in ecological and conservation studies is discussed.
9

Temporal and frequency processing in bat inferior colliculus /

Lu, Yong, January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 206-223). Also available on the Internet.
10

Temporal and frequency processing in bat inferior colliculus

Lu, Yong, January 1999 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1999. / Typescript. Vita. Includes bibliographical references (leaves 206-223). Also available on the Internet.

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