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Submitted by Renata Lopes (renatasil82@gmail.com) on 2016-04-06T18:38:52Z No. of bitstreams: 1 franciscocarlosrodriguescoelho.pdf: 4497321 bytes, checksum: 84c61f06bc2ac3aae79f57fc04d6cb0f (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2016-04-24T03:52:25Z (GMT) No. of bitstreams: 1 franciscocarlosrodriguescoelho.pdf: 4497321 bytes, checksum: 84c61f06bc2ac3aae79f57fc04d6cb0f (MD5) / Made available in DSpace on 2016-04-24T03:52:25Z (GMT). No. of bitstreams: 1 franciscocarlosrodriguescoelho.pdf: 4497321 bytes, checksum: 84c61f06bc2ac3aae79f57fc04d6cb0f (MD5) Previous issue date: 2013-08-16 / CAPES - Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / A alocação de geração distribuída em sistemas de distribuição de energia elétrica consiste em definir a localização ótima para instalação de centrais geradoras distribuídas no sistema e a quantidade de potência que deverá ser injetada por estas centrais, de modo a minimizar as perdas técnicas inerentes aos sistemas de distribuição. Este é um problema de otimização de difícil solução e que apresenta implicações ambientais e econômicas. A técnica de otimização empregada nesta pesquisa para determinar a alocação dos geradores distribuídos é recente, sendo a mesma bioinspirada. Ela se baseia na ecolocalização de morcegos e foi desenvolvida em 2010 pelo pesquisador Xin-She Yang. Esta técnica de otimização agrega em sua constituição conhecimento prévio adquirido por outras técnicas de otimização, como enxame de partículas e busca harmônica, utilizando assim, as vantagens inerentes a cada uma destas ferramentas. Esta característica confere à otimização via ecolocalização uma expectativa de sucesso em problemas de difícil solução, com características combinatórias, que é o caso do problema em estudo. Com o intuito de melhorar o desempenho da técnica de otimização em questão, foi proposta uma etapa adicional em sua constituição. Esta alteração no algoritmo original se mostrou eficiente nas simulações realizadas, pois o mecanismo de busca modificado alcançou resultados de melhor qualidade com maior frequência, tanto em sua validação, onde foram utilizadas funções matemáticas não convexas, como na aplicação do método ao problema referente à alocação de geração distribuída em sistemas de distribuição de energia elétrica. Utilizando-se três sistemas teste, de trinta e três, de cinquenta e de sessenta e nove barras, foram realizados testes com alocação exclusiva de potência ativa e reativa, e também alocação simultânea destes dois tipos de potência, sendo que os resultados obtidos foram comparados com resultados presentes na literatura especializada. Além das perdas, fatores como perfil de tensão resultante nas barras e trajetória de convergência do algoritmo inspirado na ecolocalização de morcegos foram analisados para a avaliação da metodologia de otimização empregada nesta pesquisa. / The optimal distributed generation placement in electrical power systems is a complex problem involving environmental and economical issues. The solution to this problem consists of choosing the optimum location of distributed power plants, and to define the amount of power that must be injected by these plants in order to minimize technical losses in electrical distribution systems. The optimization technique utilized in this work to determine the placement of distributed generators is recent. It was developed in 2010 by Xin-She Yang. The optimization procedure is inspired by the echolocation of bats phenomenon, and uses some previous knowledge from others techniques, like Particle Swarm Optimization and Harmony Search, combining their advantages. This feature gives the Bat-Inspired Algorithm an expectation of success on difficult problems, such as the combinatorial problem under study. In order to improve the performance of the optimization technique an additional step was proposed in its search engine. Endowed with this change, the algorithm has achieved better results more frequently. Nonconvex benchmark mathematical functions were used, as well as in its application on distributed generation placement. Using three different bus systems (33, 50 and 69 busses), simulations were performed placing real and reactive Power separately, and those two kind of Power together. The produced results were compared to specialized literature. Real power losses, bus voltage and convergence trajectory indicates the level of success reached by the optimization technique utilized in this research work.

Thesis (S.M. in Oceanographic Engineering)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering; and the Woods Hole Oceanographic Institution), 1999. / Includes bibliographical references (leaves 85-89). / by Qiang Wang. / S.M.in Oceanographic Engineering

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Thesis (Ph. D.)--Joint Program in Biological Oceanography (Massachusetts Institute of Technology, Dept. of Biology; and the Woods Hole Oceanographic Institution), 1999. / Includes bibliographical references. / Odontocetes are assumed to use echolocation for navigation and foraging, but neither of these uses of biosonar has been conclusively demonstrated in free-ranging animals. Many bats are known to use echolocation throughout foraging sequences, changing the structure and timing of clicks as they progress towards prey capture. For odontocetes, however, we do not know enough about their foraging behavior to describe such sequences. To conduct detailed behavioral observations of any subject animal, the observer must be able to maintain continuous visual contact with the subject for a period commensurate with the duration of the behavior(s) of interest. Behavioral studies of cetaceans, which spend approximately 95% of their time below the water's surface, have been limited to sampling surface behavior except in special circumstances, e.g. clear-water environments, or with the use of technological tools. I addressed this limitation through development of an observation platform consisting of a remote controlled video camera suspended from a tethered airship with boat-based monitoring, adjustment, and recording of video. The system was used successfully to conduct continuous behavioral observations of bottlenose dolphins in the Sarasota Bay, FL area. This system allowed me to describe previously unreported foraging behaviors and elucidate functions for behaviors already defined but poorly understood. Dolphin foraging was modeled as a stage-structured sequence of behaviors, with the goal-directed feeding event occurring at the end of a series of search, encounter, and pursuit behaviors. The behaviors preceding a feeding event do not occur in a deterministic sequence, but are adaptive and plastic. A single-step transition analysis beginning with prey capture and receding in time has identified significant links between observed behaviors and demonstrated the stage-structured nature of dolphin foraging. Factors affecting the occurrence of specific behaviors and behavioral transitions include mesoscale habitat variation and individual preferences. The role of sound in foraging, especially echolocation, is less well understood than the behavioral component. Recent studies have explored the use of echolocation in captive odontocete foraging and presumed feeding in wild animals, but simultaneous, detailed behavioral and acoustic observations have eluded researchers. The current study used two methods to obtain acoustic data. The overhead video system includes two towed hydrophones used to record 'ambient' sounds of dolphin foraging. The recordings are of the 'ambient' sounds because the source of the sounds, i.e. animal, could not be localized. Many focal follows, however, were conducted with single animals, and from these records the timing of echolocation and other sounds relative to the foraging sequence could be examined. The 'ambient' recordings revealed that single animals are much more vocal than animals in groups, both overall and during foraging. When not foraging, single animals vocalized at a rate similar to the per animal rate in groups of>=2 animals. For single foraging animals, the use of different sound types varies significantly by the habitat in which the animal is foraging. These patterns of use coupled with the characteristics of the different sound types suggest specific functions for each. The presence of multiple animals in a foraging group apparently reduces the need to vocalize, and potential reasons for this pattern are discussed. In addition, the increased vocal activity of single foraging animals lends support to specific hypotheses of sound use in bottlenose dolphins and odontocetes in general. The second acoustic data collection method records sounds known to be from a specific animal. An acoustic recording tag was developed that records all sounds produced by an animal including every echolocation click. The tag also includes an acoustic sampling interval controller and a sensor suite that measures pitch, roll, heading, and surfacing events. While no foraging events occurred while an animal was wearing an acoustic data logger, the rates of echolocation and whistling during different activities, e.g. traveling, were measured. / by Douglas Paul Nowacek. / Ph.D.

Made available in DSpace on 2014-12-17T15:37:13Z (GMT). No. of bitstreams: 1 MariliaASB_DISSERT.pdf: 1394968 bytes, checksum: b076e332a2c3f4b9375156425fad6f0f (MD5) Previous issue date: 2012-05-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Bats correspond to 20% of the extant mammal species and, with a few exceptions, use echolocation, a spacial orientation system based on emission and analysis of echoes from sound waves, generally ultrasounds. Echolocation was discovered in the 1940 s and since the 1970 s ultrasound detectors have been commercially available, allowing the investigation of several aspects of the natural history and ecology of bats. Passive acoustic monitoring has been frequently used in habitat use studies, predominantly in North America and Europe, by comparing the number of bat passes between different habitat types. This dissertation presents the first evaluation of the spacial and seasonal variation patterns in the activity of insectivorous bats in the Brazilian biome Pampa, in the state of Rio Grande do Sul. Since bat activity can vary according to habitat type, time of year and climatic conditions, the following hypotheses were tested: 1. bat activity varies between different types of habitat; 2. bat activity varies seasonally; 3. bat activity is influenced by temperature, humidity and wind speed. The acoustic samples were taken along fixed transects of 1500 meters, which were monitored monthly from April 2009 to March 2010. Five habitat types were sampled: eucalypts, stream, riparian forest, wetland and grassland. In each sample, the number of bat passes was obtained by using an ultrasound detector Pettersson D230. A total of 1183 bat passes were registered. Greater bat activity levels was observed along large eucalypts (1.93 bat passes/3min) and along a stream (1.61 bat passes/3 min). A riparian forest (0.94 bat passes/3 min) and a wetland area (0.61 bat passes/3 min) exhibited statistically equal levels of activity. Bat passes were fewer in grassland areas (0,16 bat passes/3 min). Bat activity was not correlated with abiotic factors. However, bat activity was significantly low in the colder season, winter, and was similar in autumn, spring and summer. The observed preference for vegetation borders and water courses agrees with reports from other countries and is attributed predominantly to the high prey abundance in these types of environments. Additionally, low activity in the winter is probably a response to the reduced availability of insects, and to lower temperatures. Our results indicate which areas of arboreal vegetation and water courses should be priorities for the conservation of bats and that alterations of these habitat types might negatively influence bat activity in the region / Os morcegos correspondem a 20% dos mam?feros atuais e, com poucas exce??es, apresentam ecolocaliza??o, um sistema de orienta??o espacial a partir da emiss?o e an?lise de ecos de ondas sonoras, geralmente ultrassons. A ecolocaliza??o foi descoberta na d?cada de 1940 e a partir de 1970 detectores de ultrassons tornaram-se comercialmente dispon?veis, permitindo a investiga??o de diversos aspectos sobre hist?ria natural e ecologia de morcegos. Monitoramentos ac?sticos passivos tem sido frequentemente utilizados em estudos de uso de h?bitat, principalmente na Am?rica do Norte e Europa, comparando-se diferentes locais quanto ao n?mero de vezes em que morcegos s?o detectados. A presente disserta??o apresenta a primeira avalia??o de padr?es espaciais e sazonais na atividade de quir?pteros inset?voros do Brasil, realizada no bioma Pampa, Estado do Rio Grande do Sul. Uma vez que a atividade de morcegos pode variar de acordo com o h?bitat, o per?odo do ano e condi??es clim?ticas, foram testadas as seguintes hip?teses: 1. a atividade de morcegos ? heterog?nea entre diferentes tipos de h?bitat; 2. a atividade apresenta varia??es sazonais; 3. a atividade ? influenciada pela temperatura, umidade e velocidade do vento. As amostragens ac?sticas foram realizadas em transectos fixos de 1500 metros, monitorados mensalmente de abril de 2009 a mar?o de 2010. Os transectos abrangeram cinco tipos de h?bitat: Eucaliptos, Mata Ciliar, Banhado, Canal e Campo. Em cada amostragem, foram obtidos o n?mero de registros de atividade com um detector de ultrassons Pettersson D230. No total, foram obtidos 1183 registros de atividade, sendo que os maiores n?veis de atividade de quir?pteros foram observados em ?rea de ?rvores de eucaliptos de grande porte (1,93 registros/3 min) e de um canal (1,61 registros/3 min). Em segundo lugar, a borda de uma mata ciliar (0,94 registros/3 min) e a margem de um banhado (0,61 registros/3 min) apresentaram n?veis estatisticamente equivalentes de atividade. As ?reas de campo foram menos utilizadas. A atividade de quir?pteros n?o apresentou correla??o com os fatores abi?ticos. Por?m, foi significativamente menor na esta??o mais fria, o inverno, e apresentou valores similares no outono, primavera e ver?o. A prefer?ncia por bordas de vegeta??o e cursos d??gua coincide com o documentado para outros pa?ses e ? atribu?da principalmente ? concentra??o de presas nestes tipos de ambiente. Do mesmo modo, a diminui??o da atividade no inverno ? provavelmente uma resposta ? menor disponibilidade de insetos, al?m das baixas temperaturas. Nossos dados indicam que ?reas de vegeta??o arb?rea e cursos d??gua s?o priorit?rias para a conserva??o de morcegos e que altera??es nestes tipos de h?bitat tendem a influenciar negativamente a atividade de morcegos na regi?o

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Die Physik der Lauterzeugung (Phonation) wurde mit Hilfe der Theorie der Nichtlinearen Dynamik untersucht. Digitale Hochgeschwindigkeitsaufnamen von Schwingungen in menschlichen und nichtmenschlichen Kehlkoepfen, digitale Bildanalyse, Signalanalyse und Modenanalyse wurden zur quantitativen Beschreibung nichtlinearer Phaenomene eingesetzt. Es wurden nichtlineare Phaenomene bei stimmkranker (pathologischer) menschlicher Lauterzeugung untersucht, wie auch in stimmgesunden Singstimmen und in Kehlkoepfen von nichtmenschlichen Saeugetieren mit Stimmlippen-Membranen. Durch Bifurkationsanalyse eines einfachen mathematischen Modells fuer Stimmlippen mit Membranen konnten beobachtete Lautmuster nichtmenschlicher Saeugetiere qualitativ "nichtlinear gefittet" werden. Die Schwerpunkte dieser Arbeit waren: 1. die Klassifikation von Lautmustern in zeitgenoessischer Vokalmusik, um Erzeugungsmechanismen fuer komplexe Stimmklaenge zu erklaeren, die im kuenstlerischen Kontext vorkommen. Im besonderen war die Rolle der Quelle-Trakt-Kopplung von Interesse; 2. Instabilitaeten in Stimmpatienten, die durch Asymmetrien in einzelnen Stimmlippen wie auch zwischen den Stimmlippen verursacht wurden; 3. dynamische Effekte von duennen, leichten und schwingenden Stimmlippen-Membranen, vertikalen Fortsaetzen der Stimmlippen bei Saeugetieren. Stimmlippen-Membrane finden sich in Kehlkoepfen von Fledermaeusen und Primaten, wo sie einerseits zur Ultraschallerzeugung verwendet werden und andererseits fuer eine grosse Lautvielfalt sorgen. Ein Stimmlippen-Membran-Modell wurde entwickelt, um dieses diverse Lautrepertoire zu reproduzieren. Dieses Modell zeigte zwei Stimmregister. Ueber die Geometry der Stimmlippen-Membrane konnte der subglottale Einsatzdruck minimiert werden und der Druckbereich fuer Phonationen vergroessert werden. Numerische Simulationen demonstrierten, dass das phaenomenologische Stimm-Membran-Modell das Lautrepertoire von Fledermaeusen und Primaten qualitativ reproduzieren konnte. / In this thesis, the physics of phonation was discussed using the theory of nonlinear dynamics. Digital high speed recordings of human and nonhuman laryneal oscillations, image processing, signal analysis, and modal analysis have been used to quantitatively describe nonlinear phenomena in pathological human phonation, healthy voices in singing, and nonhuman mammalian larynges with vocal membranes. Bifurcation analysis of a simple mathematical model for vocal folds with vocal membranes allowed a qualitative ''nonlinear fit'' of observed vocalization patterns in nonhuman mammals. The main focus of the present work was on: 1. the classification of vocalizations of contemporary vocal music to provide insight to production mechanisms of complex sonorities in artistic contexts, especially to nonlinear source-tract coupling; 2. pathological voice instabilities induced by asymmetries within single vocal folds and between vocal folds; 3. the dynamic effects of thin, lightweight, and vibrating vocal membranes as upward extensions of vocal folds in nonhuman mammals. In nonhuman mammals, vocal membranes are one widespread morphological variation of vocal folds. In bats they are responsible to produce ultrasonic echolocation calls. In nonhuman primates they facilitate the production of highly diverse vocalizations. A vocal membrane model was developed to understand the production of these complex calls. Two voice registers were found in the vocal membrane model. The vocal membrane geometry could minimize phonation onset pressure and enlarge the phonatory pressure range of the model. Numerical simulations of the model revealed instabilities that qualitatively resembled observed vocalization patterns in bats and primates.