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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

Clicking caterpillars: acoustic aposematism in Antheraea polyphemus and other Bombycoidea /

Brown, Sarah G., January 1900 (has links)
Thesis (M.Sc.) - Carleton University, 2007. / Includes bibliographical references (p. 49-49-53). Also available in electronic format on the Internet.
32

Sound duration selectivity in bat midbrain inferior colliculus

Wu, Chung-Hsin, January 2006 (has links)
Thesis (Ph. D.) University of Missouri-Columbia, 2006. / The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file (viewed on August 9, 2007) Vita. Includes bibliographical references.
33

The vocal behavior of white whales, Delphinapterus leucas, summering in an arctic estuarine habitat /

Sjare, Becky L. January 1985 (has links)
No description available.
34

The vocal repertoire of Hyla crucifer

Hurst, Nancy Case January 1982 (has links)
A new, tapered call was discovered in the Hyla crucifer repertoire with the aid of a digital processing oscilloscope. The attack transient was found to be a distinguishing characteristic between the newly discovered tapered call and other calls. Energy requirements for production of the tapered call, peep and trill were calculated and the trill was found to have a much lower energy outlay than the other calls. The implications of the lower energy expenditure in a trill are considered, and the possibility of two calls in the H. crucifer repertoire being nodes in a graded signal is discussed. / Master of Science
35

Importance of the kappa opoid system for ultrasonic vocalizations of young rats: Role of peripherally-versus centrally-located kappa opioid receptors

Osburn, James Roy 01 January 2008 (has links)
The purpose of this thesis was to determine whether the kappa opioid receptors modulating ultrasonic vocalizations production are located in the central and/or peripheral nervous system.
36

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
37

Detection of immature rice weevils, Sitophilus oryzae L. (Curculionidae, Coleoptera) by audio amplification

Pesho, George Robert. January 1954 (has links)
LD2668 .T4 1954 P47 / Master of Science
38

Dynamics Of Cricket Song Towards Nature-inspired MEMS Speakers

Godthi, Vamsy 30 July 2015 (has links) (PDF)
The clever designs of natural transducers are a great source of inspiration for man-made systems. At small length scales, there are many transducers in nature that we are now beginning to understand and learn from. Here, we present an example of such a transducer that is used by field crickets to produce their characteristic song. This transducer uses two distinct components—a file of discrete teeth and a plectrum that engages intermittently to produce a series of impulses forming the loading, and an approximately triangular membrane, called the harp, that acts as a resonator and vibrates in response to the impulse-train loading. The file-and-plectrum act as a frequency multiplier taking the low wing beat frequency as the input and converting it into an impulse-train of sufficiently high frequency close to the resonant frequency of the harp. The forced vibration response results in beats producing the characteristic sound of the cricket song. Based on various experimental observations reported in the literature, we model the sound production mechanism as consisting of three stages—actuator, frequency multiplier, and amplifier. We then examine how different features of the forewing govern the sound production. With careful experiments on the harp, we estimate the actual modulus of the harp cuticle and also measure the morphological features of the forewings of different field cricket species. Using this data, we construct a finite element model of the harp and carry out modal analysis to determine its natural frequency. We fine tune the model with appropriate elastic boundary conditions to match the natural frequency of the harp of a particular species—Gryllus bimaculatus. We model impulsive loading based on a loading scheme reported in the literature and predict the transient response of the harp. We show that the harp indeed produces beats and its frequency content matches closely that of the recorded song. Subsequently, we use our FEM model to show that the natural design is quite robust to structural perturbations in the file. The characteristic song frequency produced is unaffected by small variations in the spacing of file-teeth and even by larger gaps. We then attempt to predict a scaling law that crickets must use for spectrum allocation. We use our FEM model, with measurements and computations, to arrive at a predictive model that relates call frequencies of field crickets to the harp dimensions. We verify the validity of this model by using the measured dimensions of harps of nine field cricket species. We then use our model to provide possible explanations as to why the song frequency of various field crickets in our study is bounded between 3.1 kHz and 6.8 kHz. We also show that we are faced with similar challenges as crickets when designing miniature MEMS (Micro-Electro-Mechanical Systems) speakers. We present a design of MEMS speakers that is inspired by how the crickets actuate. We have been able to realize our first prototypes using simple fabrication processes. By electrostatically actuating the MEMS devices, we obtain a sound pressure of 70 dB SPL at a distance of 10 cm. We believe that with a few design and fabrication iterations, we will be able to achieve a much higher sound pressure output from the MEMS speakers.
39

Drumming Behavior of Selected Nearctic Stoneflies (Plecoptera)

Zeigler, David D. 08 1900 (has links)
Drumming was recorded for 11 of 13 Nearctic stonefly species, representing 4 families. Both male and female signals were obtained from 5 species, and were either 2-way or 3-way communications. Signals were species-specific; those of males and females varied from 3-39 and 1-14 beats/ signal, respectively. Duration of male signals varied from 105-8,016 ms; those of females, except Perlinella drymo (1 beat), varied from 402-1318 ms. Signals among related taxa showed greatest similarities. Duration of male signals of Perlinella drymo became progressively shorter at each of 4 temperatures from 7-29 0C. Females of Perlinella drymo would only repeatedly answer male signals recorded at near their own temperature, and would not repeatedly answer recorded male signals of 8 other species.
40

A Passive Acoustic and Experimental Study of Juvenile Blue Catfish, Ictalurus furcatus, Sound Production and Agnostic Behavior in the Tidal Freshwater James River

Morgan, Laura 05 May 2014 (has links)
Blue catfish, Ictalurus furcatus, are an invasive species in the James River, VA. They produce stridulation sounds and passive acoustic monitoring may prove useful in locating and monitoring their populations. Little is known about their behavior, therefore my goal was to examine agonistic behavior and the use of sound in defending a territory. This thesis consists of two manuscripts: 1) A passive acoustic study of the tidal freshwater James River, 2) An experimental study of agonistic behavior in juvenile Blue catfish, Ictalurus furcatus. The first study showed that three sounds (click, run croak) occurred more often in warmer months than cooler months. The second study showed that Blue catfish utilized a variety of agonistic behaviors in territory defense, with residency status and size having an effect on the type and number of displays used. Stridulation sounds were not present in territorial contests although Blue catfish produce stridulatory pulses when held.

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