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Στην εργασία αυτή πραγματοποιείται μελέτη και εφαρμογή της μεθόδου ανάλυσης ανεξάρτητων συνιστωσών. Αφού παρουσιαστούν οι τεχνικές της μεθόδου και τα μαθηματικά μοντέλα που χρησιμοποιεί εξετάζεται η εξαγωγή ερμηνεύσιμων σημάτων που αντιστοιχούν στον καρδιακό ρυθμό και την αναπνοή. Ο κύριος αλγόριθμος που χρησιμοποιείται για το διαχωρισμό των σημάτων είναι ο FastICA. / -

Sexual selection is a frame of reference that attempts to explain exaggerated signaling traits, including acoustic signals between male and female animals. Contemporary studies in the field of sexual selection are focused on the evolution of female mating preferences, with particular emphasis being placed on the good genes models of sexual selection. Here I investigate whether sexual selection is in operation in the acoustic communication system of the field cricket, Gryllus bimaculatus. Through development of new methodology I show that female crickets have a distinct and repeatable preference and selectivity for certain male song traits. For sexual selection to operate in acoustic communication systems, males must advertise some aspect of their phenotype that will influence female choice. I demonstrate that the basis for arguments invoking sexual selection for spectral song traits in a sister species, G. campestris, which is that tegmen harp area predicts song frequency, is an invalid assumption for sound production in G. bimaculatus. As a result of this finding I investigated what aspects of male song were condition- and morphology-dependent. Temporal and spectral male song traits did not convey information regarding body condition, body size or the ability to withstand developmental instability (as indicated by fluctuating asymmetry). I was unable to detect handicap sexual selection for spectral characteristics of male song despite repeatable female preference for male song frequency. Furthermore, female preference for spectral bandwidth of male song, thought to be a sexually selected trait, was shown to be governed by preference for frequency and therefore not a distinct preference. The lack of detectable sexual selection, together with observed patterns of phenotypic variation in signals and the equivalent response system, suggest that some of the male song traits function for mate recognition. However, sexual selection for call traits not considered here (e.g. duration of calling) is probable. / Dissertation (MSc (Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted

Acoustic signals are widely used by fish such as pomacentrids, to communicate during courtship and agonistic activities. Adult Stegastes lividus holds a permanent territory in a coral reef environment. Previous studies suggested that S. lividus seems to produce clicking sounds when intruders close to its territory. This study aimed to describe (1) the sounds produced by this species; (2) the behavioral pattern associated with these acoustic signals; (3) vocal activity of diurnal variation. The study site was near the water inlet of the Third Nuclear Power Plant in southern Taiwan (120¡C45¡¬E , 21¡C57¡¬N). 24-hour recordings at the habitat of S. lividus at 5-6 m and at 2-3 m were made in February, March and April, 2005. The synchronous video-audio recordings were also made at the colonies of S. lividus at 2-3 m. The observations showed that S. lividus produced clicking sounds for territorial defense (e.g. aggressive behavior). These sounds were composed of a variable number of pulses that had a dominant frequency at 200 to 400 Hz. Stegastes lividus produced different sound types to defend against conspecifics or heterospecifics. Although the acoustic signals were emitted throughout all day, more sounds were recorded during the noon, fewer sounds at night, and a small peak presented at sunset. Therefore, I suggested the acoustic signals of S. lividus may be also serves as species recognition. The fish may be a diurnal fish, and its social interaction peaks at noon.

Accurate methods for glottal feature extraction include the use of high-speed video imaging (HSVI). There have been previous attempts to extract these features with the acoustic recording. However, none of these methods compare their results with an objective method, such as HSVI. This thesis tests these acoustic methods against a large diverse population of 46 subjects. Two previously studied acoustic methods, as well as one introduced in this thesis, were compared against two video methods, area and displacement for open quotient (OQ) estimation. The area comparison proved to be somewhat ambiguous and challenging due to thresholding effects. The displacement comparison, which is based on glottal edge tracking, proved to be a more robust comparison method than the area. The first acoustic methods OQ estimate had a relatively small average error of 8.90% and the second method had a relatively large average error of -59.05% compared to the displacement OQ. The newly proposed method had a relatively small error of -13.75% when compared to the displacements OQ. There was some success even though there was relatively high error with the acoustic methods, however, they may be utilized to augment the features collected by HSVI for a more accurate glottal feature estimation.

Submitted by (ana.araujo@ufrpe.br) on 2016-08-22T11:50:51Z No. of bitstreams: 1 Edvania do Nascimento Pereira.pdf: 1151466 bytes, checksum: 9e3056541ef3069eec6437152cf19482 (MD5) / Made available in DSpace on 2016-08-22T11:50:52Z (GMT). No. of bitstreams: 1 Edvania do Nascimento Pereira.pdf: 1151466 bytes, checksum: 9e3056541ef3069eec6437152cf19482 (MD5) Previous issue date: 2015-07-13 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The acoustic signals in frogs are important for communication, being effective in transmitting information. These songs can be influenced by abiotic factors such as temperature and relative humidity, and biotic factors such as the size of the reproductive aggregates, size and body mass of animals. This study aimed to analyze the physical structure of different vocalizations S. prasinus, the social context in which they occurred and the body posture of individuals at the time of issuance of sounds. In addition to checking whether abiotic factors (temperature and relative humidity) and biotic (animal body size, body mass, presence of males and sexually mature females in the neighborhood, temperature, and relative humidity) influence the advertisement call and the organization of seasonal chorus. For recording acoustic data was using a digital recorder, through the internal omnidirectional microphones. Abiotic data were recorded (temperature and relative humidity) and biotic (micro-habitat of vocalization, the margin distance, distance from the nearest individual, data on CRC (cloacal face length) and body mass of individuals). To assist in the identification and differentiation of vocalizations, in addition to behavioral data was conducted experiment of "playback". 200 corners of 22 individuals were analyzed. They classified three types of vocalizations emitted by males of S. prasinus: advertisement call, cutting and territorial. Distinctions were found between the territorial corners with ad and cut. However, there exist differences between cutting corners and announcement, which can be important to avoid the notice of the female presence in the corner site for other males. The average amplitude of the advertisement call was the parameter that got a greater correlation with the presence of male and sexually mature females. With the objective to maintain minimum spacing between neighbors and increase mating success. The corner of the activities peaks occurred in February and March (hottest), which is common in tropical frogs due to ectotermia. Valuable results on acoustic communication and the influence of abiotic and biotic factors on acoustic parameters of sound S. prasinus, contributing information on the natural history of the species, assisting with important elements for conservation of sensitive taxa environmental changes. / Os sinais acústicos em anuros são importantes para a comunicação, sendo eficaz na transmissão de informações. Esses cantos podem sofrer influências de fatores abióticos, como temperatura e umidade relativa do ar e fatores bióticos como o tamanho dos agregados reprodutivo, tamanho e massa corpórea dos animais. Este trabalho teve por objetivo analisar a estrutura física das diferentes vocalizações de S. prasinus, o contexto social em que ocorreram e a postura corporal dos indivíduos no momento da emissão dos sons. Além de verificar se fatores abióticos (temperatura e umidade relativa do ar) e bióticos (tamanho do corpo dos animais, massa corpórea, presença de machos e fêmeas sexualmente maduros na vizinhança, temperatura, e umidade relativa do ar) influenciam no canto de anúncio e na organização do coro sazonalmente. Para a gravação dos dados acústicos foi utilizando um gravador digital, através dos microfones omnidirecionais internos. Foram anotados os dados abióticos (temperatura e umidade relativa do ar), e bióticos (micro-habitat de vocalização, distância da margem, distância do individuo mais próximo, dados sobre o CRC (comprimento rosto cloacal) e massa corpórea dos indivíduos). Para auxiliar na identificação e diferenciação das vocalizações, além dos dados comportamentais foi realizado experimento de "playback". Foram analisados 200 cantos, de 22 indivíduos. Classificaram-se três tipos de vocalizações emitidos por machos de S. prasinus: canto de anúncio, corte e territorial. Foram encontradas distinções entre os cantos territoriais com os de anúncio e corte. Contudo, não existiriam diferenças entre os cantos de corte e de anúncio, o que pode ser importante para evitar o aviso da presença da fêmea no sítio de canto para outros machos. A amplitude média do canto de anúncio foi o parâmetro que obteve uma maior correlação com a presença de machos e fêmeas sexualmente maduros. Tendo por objetivo manter espaçamento mínimo entre vizinhos e aumentar o sucesso no acasalamento. Os picos de atividades do canto ocorreram nos meses de fevereiro e março (mais quentes), o que é comum em anuros tropicais, devido à ectotermia. Resultados valiosos sobre a comunicação acústica e a influência de fatores abióticos e bióticos nos parâmetros acústicos do som de S. prasinus, contribuindo com informações sobre a história natural da espécie, auxiliando com elementos importantes para conservação de grupos taxonômicos sensíveis as mudanças ambientais.

Submitted by Marlene Santos (marlene.bc.ufg@gmail.com) on 2014-10-31T20:45:10Z No. of bitstreams: 2 Dissertacao - _Raissa Furtado Souza -2014.pdf: 4152494 bytes, checksum: 231a97633d8ce288bacd912cef4349d1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Approved for entry into archive by Luciana Ferreira (lucgeral@gmail.com) on 2014-11-03T11:39:22Z (GMT) No. of bitstreams: 2 Dissertacao - _Raissa Furtado Souza -2014.pdf: 4152494 bytes, checksum: 231a97633d8ce288bacd912cef4349d1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) / Made available in DSpace on 2014-11-03T11:39:22Z (GMT). No. of bitstreams: 2 Dissertacao - _Raissa Furtado Souza -2014.pdf: 4152494 bytes, checksum: 231a97633d8ce288bacd912cef4349d1 (MD5) license_rdf: 23148 bytes, checksum: 9da0b6dfac957114c6a7714714b86306 (MD5) Previous issue date: 2014-05-21 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The efficiency of intraspecific communication directly affects male reproductive success. Acoustic signaling is the primary form of communication in nocturnal anurans. However, visual signaling can also be important in social interactions. We tested the hypothesis that open environments favor visual signals in a territorial defense context, in a nocturnal tree frog. We established three treatments with eight males of Hypsiboas albomarginatus each: i) Clear Vision, with a mirror without visual obstacles; ii) Obstructed Vision, with half the mirror covered, and iii) Control, with mirror completely covered. We classified behavioral responses into orientation/locomotion, visual display, or acoustic signal. We calculated the mean emission rate per minute per behavior in each treatment, and compared them among treatments using one-way NOVA. Orientation and locomotion, visual display, and the advertisement call did not differ among treatments. However, the emission of aggressive calls in the Obstructed Vision treatment was significantly higher than in the Clear Vision treatment. The lowest rate of aggressive calls occurred in the Control. Thus, visual recognition of an intruder male was enough for resident males to adjust their rate of emission of acoustic aggressive signals, but not visual displays. Therefore, the recognition of the intruder male is not the only feature required for the evolution of visual signals in nocturnal treefrogs during agonistic interactions. This suggests that some visual displays may not be directly used for communication, but rather constitute displacement activity. / A eficiência da comunicação intraespecífica está diretamente relacionada com o sucesso reprodutivo. A sinalização acústica é a principal forma de comunicação dos anfíbios anuros de hábito noturno. Entretanto, a sinalização visual também desempenha papel importante durante as interações sociais. Nosso objetivo foi testar a hipótese de que ambientes abertos favorecem a emissão de sinais visuais, durante interações agonísticas, em uma espécie de hilídeo noturno. Oito machos de Hypsiboas albomarginatus foram submetidos a três tratamentos: i) Visão Livre, espelho sem obstáculos visuais; ii) Visão Obstruída, metade do espelho coberto por gramíneas; e iii) Controle, espelho totalmente coberto por gramíneas. Classificamos as respostas comportamentais em orientação/locomoção, exibição visual ou sinal acústico. Calculamos, para cada tratamento, a frequência média de emissão por minuto de cada omportamentos entre os tratamentos (ANOVA). Comportamentos de orientação e locomoção, exibições visuais e o canto de anúncio não diferiram entre os tratamentos. Entretanto, a emissão de cantos agressivos durante o tratamento de Visão Obstruída foi significativamente mais alta do que no tratamento de Visão Livre. A menor emissão de cantos agressivos ocorreu durante o tratamento de Controle. Logo, o reconhecimento visual de um macho intruso foi suficiente para que o macho residente alterasse sua emissão de sinais acústicos agressivos, mas não a emissão de exibições visuais. Portanto, o reconhecimento visual de um competidor não é o único fator necessário para a evolução de sinais visuais em hilídeos noturnos durante interação agonísticas. Este resultado sugere que algumas exibições visuais podem não ser usadas diretamente para a comunicação, sendo, portanto, atividades deslocadas.

No description available.

Sound production is a widespread phenomenon in fishes; however, the importance of acoustic signals and their potential to influence reproduction has not been determined. This dissertation examines fish acoustic courtship signals to investigate whether sound has a role in reproductive success. The pre-spawning sounds of several fishes were recorded and analyzed. The male advertisement call of two species of Belizean toadfish, Sanopus astrifer and Batrachoides gilberti, were found to significantly differ. These data, coupled with data in the literature suggest an influence of habitat characteristics on the calling behavior of toadfishes. Additionally, acoustic playback experiments were employed to investigate the role of male courtship sounds in the Malawi cichlid species, Tramitichromis intermedius. Playback results indicated that male sounds may initiate egg-laying behavior in females, but may not be behaviorally relevant to conspecific males. A discussion of confounding factors in aquarium playback experiments is presented. Technical aspects of fish sound recording, playback, and analysis were also examined to provide information for future fish bioacoustics studies. It was determined that digital cameras are a useful method of recording fish sounds to describe metric characteristics; however, temporal parameters are more accurately captured by hydrophones, which are optimal for use in scientific description of fish sounds. Underwater speakers commonly used in fish playback experiments were tested for fidelity when producing a low-frequency pulsed fish sound. The Electro-Voice UW30 speaker was found to perform the best playback at low sound pressure levels (<120 dB re 1 μPa) and at short distances (< 15 cm). The Clark Synthesis AQ339 speaker performed the best playback at higher sound pressure levels (>120 dB re 1 μPa) and at greater distances than the UW30. Many fish sounds have been described in the literature; however, there is no standardization of sample size used in species descriptions. A method is presented that can be used to estimate the level of inclusiveness of sound variability in sound descriptions, and to approximate sufficient sample sizes of recordings. The courtship calls of Dascyllus albisella and Batrachoides gilberti were examined to illustrate this method and to provide a benchmark for future sound descriptions.

This dissertation explores the realm of high-accuracy localization through the utilization of ranging-based techniques, encompassing a spectrum of signals ranging from low-frequency ultrasound acoustic signals to more intricate high-frequency signals like Wireless Fidelity (Wi-Fi) IEEE 802.11az, 5G New Radio (NR), and 6G. Moreover, another contribution is the conception of a novel timing mechanism and synchronization protocol grounded in tunable quantum photonic oscillators. In general, our primary focus is to facilitate precise indoor localization, where conventional GPS signals are notably absent. To showcase the significance of this innovation, we present two vital use cases at the forefront: drone localization and metaverse user positioning. In the context of indoor drone localization, the spectrum of applications ranges from recreational enthusiasts to critical missions requiring pinpoint accuracy. At the hobbyist level, drones can autonomously navigate intricate indoor courses, enriching the recreational experience. As a finer illustration of a hobbyist application, consider the case of ``follow me drones". These specialized drones are tailored for indoor photography and videography, demanding an exceptionally accurate autonomous flight capability. This precision is essential to ensure the drone can consistently track and capture its designated subject, even as it moves within the confined indoor environment. Moving on from hobby use cases, the technology extends its profound impact to more crucial scenarios, such as search and rescue operations within confined spaces. The ability of drones to localize with high precision enhances their autonomy, allowing them to maneuver seamlessly, even in environments where human intervention proves challenging. Furthermore, the technology holds the potential to revolutionize the metaverse. Within the metaverse, where augmented and virtual realities converge, the importance of high-accuracy localization is amplified. Immersive experiences like Augmented/Virtual/Mixed Reality (AR/VR/MR) gaming rely heavily on precise user positioning to create seamless interactions between digital and physical environments. In entertainment, this innovation sparks innovation in narrative design, enhancing user engagement by aligning virtual elements with real-world surroundings. Beyond entertainment, applications extend to areas like telemedicine, enabling remote medical procedures with virtual guidance that matches physical reality. In light of all these examples, the imperative for an advanced high-accuracy localization system has become increasingly pronounced. The core objective of this dissertation is to address this pressing need by engineering systems endowed with exceptional precision in localization. Among the array of potential techniques suitable for GPS-absent scenarios, we have elected to focus on ranging-based methods. Specifically, our methodologies are built upon the fundamental principles of time of arrival, time difference of arrival, and time of flight measurements. In essence, each of our devised systems harnesses the capabilities of beacons such as ultrasound acoustic sensors, 5G femtocells, or Wi-Fi access points, which function as the pivotal positioning nodes. Through the application of trilateration techniques, based on the calculated distances between these positioning nodes and the integrated sensors on the drone or metaverse user side, we facilitate robust three-dimensional localization. This strategic approach empowers us to realize our ambition of creating localization systems that not only compensate for the absence of GPS signals but also deliver unparalleled accuracy and reliability in complex and dynamic indoor environments. A significant challenge that we confronted during our research pertained to the disparity in z-axis localization performance compared to that of the x-y plane. This nuanced yet pivotal concern often remains overlooked in much of the prevailing state-of-the-art literature, which predominantly emphasizes two-dimensional localization methodologies. Given the demanding context of our work, where drones and metaverse users navigate dynamically across all three dimensions, the imperative for three-dimensional localization became evident. To address this, we embarked on a comprehensive analysis, encompassing mathematical derivations of error bounds for our proposed localization systems. Our investigations unveiled that localization errors trace their origins to two distinct sources: errors induced by ranging-based factors and errors stemming from geometric considerations. The former category is chiefly influenced by factors encompassing the quality of measurement devices, channel quality in which the signal communication between the sensor on the user and the positioning nodes takes place, environmental noise, multipath interference, and more. In contrast, the latter category, involving geometry-induced errors, arises primarily from the spatial configuration of the positioning nodes relative to the user. Throughout our journey, we dedicated efforts to mitigate both sources of error, ensuring the robustness of our system against diverse error origins. Our approach entails a two-fold strategy for each proposed localization system. Firstly, we introduce innovative techniques such as Frequency-Hopping Spread Spectrum (FHSS) and Frequency-Hopping Code Division Multiple Access (FH-CDMA) and incorporate devices such as Reconfigurable Intelligent Surfaces (RIS) and photonic oscillators to fortify the system against errors stemming from ranging-related factors. Secondly, we devised novel evolutionary-based optimization algorithms, adept at addressing the complex NP-Hard challenge of optimal positioning node placement. This strategic placement mitigates the impact of geometry-induced errors on localization accuracy across the entire environmental space. By meticulously addressing both these sources of error, our localization systems stand as a testament to comprehensive robustness and accuracy. Our methodologies not only extend the frontiers of three-dimensional localization but also equip the systems to navigate the intricacies of indoor environments with precision and reliability, effectively fulfilling the evolving demands of drone navigation and metaverse user interaction. / Doctor of Philosophy / In this dissertation, we first explore some promising substitutes for the Global Positioning System (GPS) for the autonomous navigation of drones and metaverse user positioning in indoor spaces. Then, we will make the scope of research more comprehensive and try to explore substitutes to GPS for autonomous navigation of drones in general, both in indoor environments and outdoors. For the first part, we make our small indoor GPS. Similar to GPS, in our system, a receiver onboard the drone or the metaverse user can receive signals from our small semi-satellites in the room, and with that, it can localize itself. The idea is very similar to how the well-known GPS works, with some modifications. Unlike the GPS, we are using acoustic ultrasound signals or some RF signal based on 5G or Wi-Fi for transmission. Also, we have more freedom compared to GPS because, in GPS, they have to transmit signals from far ahead distances, whereas, in our scenario, it is just a room in which we put all of our semi-satellite transmitters. Moreover, we can put them anywhere we want in the room. This is, in fact important, because the positions of these semi-satellites have a huge effect on the accuracy of our system. Also, we can decide how many of them we need to cover every point in the room and not have any blind spots. We propose our novel techniques for finding the optimal placement to improve localization accuracy. In GPS, they propose a technique that is suitable for the case of those satellites and their distance to the targets. Similarly, we offer our novel techniques to have a robust transmission against noise and other factors and guarantee a localization scheme with high accuracy. All being said, our proposed system for indoor localization of drones and metaverse users in three dimensions has considered all the possible sources of error and proposed solutions to conquer them; hence a robust system with high accuracy in three-dimensional space.