This thesis discusses a new approach to tracking the REMUS 100 AUV using a modified version of the Florida Atlantic University (FAU) ultrashort baseline (USBL) acoustic positioning system (APS). The REMUS 100 is designed to utilize a long baseline (LBL) acoustic positioning system to obtain positioning data in mid-mission. If the placement of one of the transponders of the LBL field is known, then tracking the position of the REMUS 100 AUV using a passive USBL array is possible. As part of the research for this thesis, the FAU USBL system was used to find a relative range between the REMUS 100 ranger and a LBL transponder. This relative range was then combined with direction of arrival information and LBL field component position information to determine an absolute position of the REMUS 100 ranger. The outcome was the demonstration of a passive USBL based tracking system. / by Kyle L. Seaton. / Thesis (M.S.C.S.)--Florida Atlantic University, 2013. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.

A Sindrome da Apneia Hipopneia obstrutiva do sono (SAHOS) é caracterizada por episódios repetidos de obstrução parcial (hipopneia) ou completa (apneia) das vias aéreas superiores durante o sono. Os efeitos clínicos da SAHOS estão relacionados aos efeitos cumulativos da exposição à asfixia periódica e à fragmentação do sono causada por apneias e hipopnéias, como o aumento do risco de hipertensão, disritmias noturnas, insuficiência ventricular, infarto do miocárdio e acidente vascular cerebral. O padrão ouro para o diagnóstico de SAHOS é a Polissonografia (PSG), na qual requer que o paciente permaneça durante a noite inteira no laboratorio de sono, conectado a diferentes sensores biológicos e sob a supervisão de um técnico. Além do desconforto causado pelos sensores invasivos, a necessidade de um ambiente clínico e infraestrutura altamente especializada resulta em uma longa lista de espera nos laboratórios do sono e altos custos, restringindo assim o acesso ao diagnóstico e tratamento. Para melhorar o monitoramento da evolução da OSA, o acesso ao diagnóstico e o acompanhamento do tratamento, propõe-se uma solução baseada em Mobile Health (mHealth) para utilizar os recursos do smartphone a fim de desenvolver uma estimativa não invasiva da gravidade da SAHOS. Utiliza-se o áudio gravado através de um smartphone para detectar automaticamente os eventos de ronco durante a noite e, através da análise desses eventos, estimar a necessidade do paciente para o tratamento de Pressão Positiva Contínua nas Vias Aéreas (CPAP). Para isso, dividimos nossa solução em duas fases: (i) uma solução completamente não supervisionada para detectar automaticamente os eventos de ronco em um ambiente não controlado e (ii) a análise das características acústicas dos eventos de ronco para estimativa de gravidade da SAHOS. Na primeira fase, podemos comprovar a viabilidade de gravar o áudio e detectar os eventos de ronco usando um smartphone em um ambiente suscetível a ruídos aleatórios. Na segunda fase, mostramos que um conjunto de características acústicas globais dos eventos de ronco pode prever a necessidade do paciente para o tratamento com CPAP. Nossa solução proposta foi avaliada em ambiente não controlado (domicílio do paciente) e controlado (laboratório do sono), atingindo resultados satisfatórios na detecção de eventos de ronco e classificação do paciente de acordo com a necessidade de tratamento com CPAP. / Obstructive Sleep Apnea (OSA) is characterized by repeated episodes of partial (hypopnea) or complete (apnea) obstruction of the upper airway during sleep. The clinical effects of OSA are related to the cumulative effects of exposure to periodic asphyxia and sleep fragmentation caused by apneas and hypopneas, such as an increased risk of hypertension, nocturnal dysrhythmias, ventricular failure, myocardial infarction, and stroke. The current gold standard for diagnosing OSA is the overnight Polysomnography (PSG), which requires a full-night sleep laboratory stay, attached to different biological sensors and under the supervision of a technician. Besides the discomfort caused by the invasive sensors, the necessity of a clinical setting and highly specialized infrastructure results in a long waiting list in sleep laboratories and high costs, thus restricting the access to diagnosis and treatment. To improve monitoring of OSA evolution, access to diagnosis and treatment follow up, we propose a Mobile Health (mHealth) solution to take advantage of the smartphone capabilities to deploy a non-invasive OSA severity estimation. We make use of the audio recorded through a smartphone to automatically detect snoring events throughout the night and through the analysis of such events estimate patient’s necessity for Continuous Positive Airway Pressure (CPAP) therapy. For that, we have divided our solution into two phases: (i) a completely unsupervised solution to automatically detect the snoring events in an uncontrolled environment and (ii) the analysis of acoustical features of the snoring events for OSA severity estimation. In the first phase, we can prove the viability of recording the audio and detect the snoring events using a smartphone under an environment susceptible to random noises. In the second phase, we show that a set of global acoustical features from the snoring events can predict the patient’s need for the CPAP therapy. Our proposed solution was evaluated in an uncontrolled (patient’s home) and controlled (sleep laboratory center) environment, reaching satisfactory results in snoring events detection and patient’s classification according to the need for CPAP therapy.

INTRODUÇÃO: A atuação fonoaudiológica na síndrome de Down tem privilegiado os aspectos de cognição, linguagem e sistema estomatognático destes indivíduos. Devido à escassez de informações a respeito da voz nos sujeitos afetados por esta síndrome, a atuação fonoaudiológica, tanto em clínica quanto em pesquisa ainda é incipiente. Este estudo parte da hipótese de que a hipotonia muscular e frouxidão ligamentar características da síndrome podem afetar o trato vocal e, conseqüentemente, a fonação destas pessoas. OBJETIVO: Caracterização da voz do jovem adulto com SD, a partir de análises acústica e perceptivo-auditiva. MÉTODOS: Participaram 55 sujeitos com síndrome de Down de 18 a 29 anos, 31 do gênero masculino e 24 do gênero feminino. O material de fala consistiu de vogais orais sustentadas do Português brasileiro e foi gravado em mini-disc. Para análise acústica foi utilizado Dr Speech 4.0, Tiger Inc. O tempo máximo de fonação foi medido com cronômetro. Para análise perceptivo-auditiva 3 juízes especialistas em voz utilizaram escala GRBASI e a avaliação de ressonância do perfil de triagem vocal de Buffallo III. Foi realizado teste de concordância inter-juízes RESULTADOS: Valores acústicos médios : F0 gênero masculino 158,42 Hz; F0 gênero feminino 216,26 Hz; jitter 0,44%; shimmer 1,85%; desvio padrão F0 4,18Hz; freqüência do tremor 2,64 Hz; amplitude do tremor 3,45 Hz, energia de ruído glótico -8,45dB; proporção harmônico-ruído 19,87dB; proporção sinal-ruído 18,04dB; tempo máximo de fonação do gênero masculino 6,46 s; tempo máximo de fonação do gênero feminino 5,75 s. Teste de concordância inter-juízes indicou concordância estatisticamente significante, exceto para o parâmetro hiponasalidade. Os juízes estimaram corretamente a idade e o gênero dos sujeitos por meio da voz. A escala GRBASI indicou: Grau global moderado; Rouquidão de normal a moderado; Soprosidade de normal a severo; Astenia com maior concentração no grau normal; Tensão de normal a moderado. A avaliação da ressonância indicou: hipernasalidade de leve a severo; hiponasalidade de leve a severo; ressonância laringo-faríngica de leve a severo; ressonância oral de normal a leve e ressonância cul-de-sac não aparece significativamente na amostra. CONCLUSÕES: F0 do gênero feminino, jitter, shimmer e medidas de ruído dentro da normalidade. F0 do gênero masculino elevada e desvio padrão da F0 aumentado. Tempo máximo de fonação altamente desviante. A identificação de idade e gênero dos sujeitos por meio da voz não foi prejudicada pela elevação da F0. As vozes foram julgadas disfônicas, porém não se pode atribuir a um único parâmetro da escala GRBASI, que teve distribuição heterogênea. Foi identificado foco ressonantal nasal na quase totalidade dos casos, variando entre hiper e hiponasal associado a foco laringo-faríngico / INTRODUCTION: Down syndrome is one of the most common genetic pathologies. Speech and Language Pathology usually deals with cognitition, language development and oral-facial muscular aspects of this syndrome. Due to the lack of information about the voice of people with Down syndrome, Specch and Language Pathology research and voice therapy is still incipient. This research was based on the hipothesis that typical muscular hypotonia and ligamentous faintness of Down syndrome may affect vocal tract and, by consequence, phonation. PURPOSE: Perform acoustical and perceptual analysis of voice of young adults with Down syndrome. METHODS: 55 subjects with Down syndrome, 31 males and 24 females, ages 18 to 29 y.o., students of special education school. Speech signal consisted of sustained vowels of brazilian Portuguese was recorded in mini-discs and, for acoustical analysis, Dr Speech 4.0, Tiger Inc. was used. Maximum phonation time was measured with a digital cronometer. 3 judges, Speech and Language Pathologists voice specialists performed perceptual analysis using GRBASI scale and ressonance evaluation of Buffallo III Vocal Profile. Inter-judge reliability was computed. RESULTS: mean acoustic values: male F0 158,42 Hz; female F0 216,26 Hz; jitter 0,44%; shimmer 1,85%; standart deviation F0 4,18Hz; tremor frequency 2,64 Hz; tremor amplitude 3,45 Hz, normalized noise energy -8,45dB; noise-to-harmonic ratio 19,87dB; signal-to-noise ratio 18,04dB; male maximum phonation time 6,46 s; female maximum phonation time 5,75 s. Inter-judge reliability test was found positive, except for hiponasality. Judges were able to correctly estimate subjects age and sex by voice listening.GRBASI scale indicated : mild Grade; normal to mild Roughness; normal to severe Breathness; normal Asteny; normal to mild Tension. Ressonance evaluation indicated: light to severe hypernasal ressonance; light to severe hyponasal ressonance; light to severe laryngeal-faringeal ressonance; normal to light oral ressonance and cul-de-sac ressonance did not appear significantly at the sample. CONCLUSIONS: Normal female F0, jitter, shimmer and noise measurements inside the normal range. High male F0 and elevated F0 standard deviation. Extremely low abnormal maximum phonation time. Despite F0 elevation, judges could estimate correctly age and sex. GRBASI scale had heterogenous distribution. Voices were classified as disphonic, but we can´t atributte this classification to an isolated parameter. Nasal ressonantal focus was identified in almost every subject, ranging between hyper and hyponasal, associated to laryngeal-faringeal focus

The purpose of this thesis is to develop a renewable ocean energy material selection methodology for use in FAU's Ocean Energy Projects. A detailed and comprehensive literature review has been performed concerning all relevant material publications and forms the basis of the developed method. A database of candidate alloys has been organized and is used to perform case study material selections to validate the developed fuzzy logic approach. The ultimate goal of this thesis is to aid in the selection of materials that will ensure the successful performance of renewable ocean energy projects so that clean and renewable energy becomes a reality for all. / by Donald Anthony Welling. / Thesis (M.S.C.S.)--Florida Atlantic University, 2009. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 2009. Mode of access: World Wide Web.

Theories about ship wake structure, bubble dynamics, acoustic propagation through bubble clouds, backscattering and target strength of bubble clouds have been investigated and related Matlab simulations have been carried on. Research has been carried on algorithms for ship wake acoustic detection and tracking. Particle filter method has been simulated with Matlab for target tracking using wake echo measurements. Simulation results are promising.

Thermoacoustic engines convert heat into acoustic pressure waves with no moving parts; this inherently results in high reliability, low maintenance and low manufacturing costs. Significant increases in the performance of these devices have enabled rivalry with more mature energy conversion methods in both efficiency and power output. This optimal production of acoustic power can be ultimately used to achieve cryogenic temperatures in thermoacoustic refrigerators, or can be interfaced with reciprocating electro-acoustic power transducers to generate electricity. This thesis describes the design, fabrication and testing of a Thermoacoustic Power Converter. The system interfaces a thermoacoustic-Stirling heat engine with a pair of linear alternators to produce 100 watts of electricity from a heat input. It operates with helium at 450 psig internal pressure and a hot side temperature of 1200F. Through thermoacoustic phenomena, these conditions sustain a powerful pressure wave at a system specific 100 Hz. This pressure wave is used to drive the two opposed linear alternators in equal and opposite directions to produce a single phase AC electrical output at that same system frequency. The opposing motion of the two alternators enables a vibration-balanced system. The engine has created 110 watts of acoustic power and the complete Thermoacoustic Power Converter system has produced 70 watts of AC electricity. Compensating for some heat leaks, the converter reaches 26.3% heat to acoustic power efficiency and 16.8% heat to electric efficiency when those maximum values are achieved. This conversion of heat to acoustic power is 40% of the Carnot thermodynamic efficiency limit.

The concept of mounting a loudspeaker on one end of a sound-absorbing tube has existed since at least 1936. Surprisingly, a detailed mathematical analysis of the configuration has not been performed, nor has a design method been established. This configuration, known as a transmission line loudspeaker, has received little consideration in the reviewed literature. Instead, it has become frequently featured in magazines for audio hobbyists, where it is experimentally designed with rules seemingly derived from hearsay and described with terms of high praise. In this dissertation, an electro-acoustical model of a fiberglass-filled transmission line is presented. This model represents the transmission line as two separate lines -- a mechanical line that models the mechanical motion of the fiberglass and an acoustical line that models the motion of the air. The lines are linked by the flow resistance of the fiberglass. From the model, solutions for the acoustic pressure, acoustical volume velocity of the air, mechanical velocity of the fiberglass fibers, and mechanical force on the fiberglass in the line are obtained. The fiberglass is characterized and empirical formulas that describe its characteristics are found. It is shown that the modeled input impedance to the transmission line is a good fit to measured data. The performance of the system is assessed by comparing it with the performances of typical loudspeaker mountings, i.e., the infinite baffle, the closed box, and the vented box. Finally, an example is shown of how the equations derived from the model can be used to evaluate the design of a transmission line loudspeaker system.

This thesis presents a study concerning stop consonant to vowel transitions which are modeled making use of acoustic tube model. Characteristics of the stop consonant to vowel transitions are tried to be obtained first. Therefore several transitions including fricative to vowel transitions are examined based on spectral and time related properties. In addition to these studies, x-ray snapshots, lip videos and also experiments including subjects are used to intensify the characterization, from the production and the perception side of views. As results of these studies the plosive to vowel transitions are observed to be uttered by exponential vocal tract movements and the perception mechanism is observed to be highly related with exponential spectral changes. A model, based on the acoustic tube model, is tried to be established using the knowledge and the experience gained during characterization therefore proposed model involves the vocal tract parameters observed in characterization part. Finally, plosive to vowel transitions including three types of plosives (alveolar, labial and velar) are synthesized by the proposed model. The formants of the synthesized sounds are compared with the formants of the natural sounds. Also the intelligibility tests of these sounds are done. Performance evaluation tests show the proposed model&rsquo / s performance to be satisfactory.

Finite element method and strip method are two widely used techniques for analyzing steel plate shear wall (SPSW) systems. Past research mostly focused on the prediction of lateral load capacity of these systems using these numerical methods. Apart from the lateral load carrying capacity, the lateral stiffness of the wall system needs to be determined for a satisfactory design. Lateral displacements and the fundamental natural frequency of the SPSW system are directly influenced by the lateral stiffness. In this study the accuracy of the finite element method and strip method of analysis are assessed by making comparisons with experimental findings. Comparisons revealed that both methods provide in general solutions with acceptable accuracy. While both methods offer acceptable solutions sophisticated computer models need to be generated. In this study two alternative methods are developed. The first one is an approximate hand method based on the deep beam theory. The classical deep beam theory is modified in the light of parametric studies performed on restrained thin plates under pure shear and pure bending. The second one is a computer method based on truss analogy. Stiffness predictions using the two alternative methods are found to compare well with the experimental findings. In addition, lateral stiffness predictions of the alternate methods are compared against the solutions provided using finite element and strip method of analysis for a class of test structures. These comparisons revealed that the developed methods provide estimates with acceptable accuracy and are simpler than the traditional analysis techniques.

Noise, which is a noteworthy problem in the world of workers, influences the health, safety, productivity and efficiency of those working in heavy industries and especially those working in petroleum industry. The objective of this study is to reassess the protective measures, taken previously by the company, from the point of view of the negative effects of noise on the workers. For this purpose, two approaches are adopted. Firstly, through questionnaires (response rate: 86%) distributed to workers, their subjective rating of, the noise levels to which they are exposed, the factors affecting their working efficiency and, their working conditions are searched. Secondly, noise levels, in the buildings rated as highly and very highly noisy, are measured by sound level meter. Self-exposure of 28 workers is measured by dosimeter. The overall ambient noise level of the 11 buildings and effect of noise on the working efficiency of the workers working in these buildings were respectively found to be moderate and slightly affected. The workplace index was 3 (out of 5). The working conditions index was on the average 4 (out of 5). The Leq values measured in six of the buildings were found to be in the range of 66, 8 &ndash / 100, 0 dBA. 12 out of 28 workers were observed to be exposed to noise levels greater than 80 dBA. The objective (noise measurements) and subjective (questionnaire) results obtained at the end of the afore-mentioned approaches will be of help in the orientation of the workers while estimating their work efficiency and will also serve as a data base for the planning strategy of the interested company.