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When playing a brass instrument the lips of the player fulfil a similar role to the cane reeds of wood-wind instruments. The nature of the motion of this lip-reed determines the ow of air through the lips, between the player's mouth and the instrument. It is a complicated feedback system in which the motion of the lips controls the air ow, which itself affects the behaviour of the lips. In recent years several designs of artificial mouth have been developed; these model the human lips using latex rubber tubes filled with water. These artificial mouths are increasingly used in experiments rather than enlisting the services of a musician as they have many advantages including greater accessibility and the stability of the embouchure. In this thesis factors affecting the reproducibility of the embouchure of one such artificial mouth are investigated with reference to the measured resonances of the lips. Using these results, procedures and practical design improvements are suggested. Two examples of comparative studies of historic instruments are presented. In order to provide detailed information on the behaviour of the lips of brass players high speed digital photography is used to image the self-oscillating lipreed. Variation in the lip opening, over a wide range of notes and different players, is investigated, providing experimental evidence to aid the process of reining physical models of the behaviour of the brass player's lips. Particular attention is paid to the relationship between the area and height of the lip opening. Results suggest that during extremely loud playing the lip motion is qualitatively similar to that in quieter notes and therefore is not the origin of the dramatic increase in the levels of the high harmonics of the radiated sound. Investigation of the behaviour at the start of a note has shown evidence relating the lip motion to the transient in the mouthpiece pressure waveform. Comparison is made between the behaviour of the artificial lips and that of the lips of musicians providing evidence of the suitability of the use of the artificial mouth as a model for real brass players. Results show that although differences exist, particularly when looking at behaviour over a wide range of dynamic levels, the general features of behaviour are reproduced by the artificial mouth.

<p> Throughout the United States, and globally, there has been recent interest in large-scale monitoring of bats, driven largely by the many threats that bats currently face such as climate change, white nose syndrome, habitat loss, and wind energy development. Additionally, many human activities generate sensory disturbances including anthropogenic light and noise pollution that have been shown to affect habitat use and foraging efficiency in bats and other wildlife. My research took place in the Piceance Basin of northwestern Colorado, where there has been considerable development of natural gas resources in recent years. During the drilling phase for natural gas, drill rigs run continuously for weeks to months at each well development site. In addition to the physical disturbance and increased human presence at the well pad, drill rigs are brightly lit, and also emit high amplitude anthropogenic noise. The light and noise from active drill rigs can travel many miles from the source, far beyond areas where wildlife habitat has been physically disturbed. The goal of my research was to isolate noise from the other associated forms of disturbance, and investigate what, if any, effects drilling noise is having on the bat community. </p><p> My dissertation is comprised of three stand-alone chapters, as follows. In Chapter 1, I test two different strategies for deploying bat detectors to determine which strategy yields higher detection and species identification rates. In Chapters 2 and 3, I present the results of noise playback experiments. Chapter 2 compares bat activity levels at control sites, and at treatment sites where noise was added experimentally. In Chapter 3, I monitor bat activity patterns both during and after a noise playback experiment to determine how rapidly activity levels recover post-exposure. A brief summary of each chapter follows. </p><p> In Chapter 1, I focus on the methods for recording bat echolocation calls, and identifying free-flying bats in the field. Unlike capture techniques, current acoustical methods for bat monitoring do not provide information about unique individuals, age, sex, or reproductive status. What acoustical monitoring can provide is information about bat activity levels, habitat use, and species identification in some cases, without interfering with bat movement, foraging, or other activities. The commercially available technology for recording bat echolocation calls has rapidly advanced, and there are many ultrasound detector&ndash;recorder systems (hereafter, &lsquo;bat detectors&rsquo;) available with a wide range of recoding options. Due to rapid attenuation of ultrasound signals, one of the challenges to acoustical monitoring is the relatively limited recording range of bat detectors. To increase this range, I took advantage of a bat detector that had the ability to record on two channels (in stereo). By attaching microphone extension cables, I was able to increase the distance between the left and right channel microphones, thereby increasing the acoustical sampling space. When this data collection effort took place, the SM2BAT+ detector from Wildlife Acoustics, Inc. was the only commercially available bat detector that had the two-channel recording capability. I deployed two identical bat detectors at each study site, and compared the recordings made using the stereo option to recordings made from a single channel. </p><p> In general, the stereo setup outperformed the single-channel systems. With the stereo microphones separated by approximately 10 m, the bat detectors that recorded in stereo produced 2.7 times more recordings overall. The increased number of recordings resulted in a higher number of calls that could be identified to species. The benefit of the stereo setup was not equal for all species. With the stereo microphones only about 10 m apart, there was some overlap between the calls that were identified on the left and right channels. The highest rate of overlap (19.5%) was in big brown bats (<i>Eptesicus fuscus </i>). Rates of overlap for species in the Myotis genus were all less than 5%, and none of the recordings of pallid bats (<i>Antrozous pallidus </i>) were identified on both channels for the same bat-pass-event. The stereo option is a promising way to increase the number of bat recordings, which may be a particularly useful when surveying for rare species. </p><p> In Chapter 2, I used a noise playback experiment to isolate noise from other forms of anthropogenic disturbance, and monitored the bat activity level response. I recorded the sounds of an active drill rig, and played these recordings at treatment sites. I measured sound pressure levels at the drill site, and estimated the sound pressure levels at the noise playback sites. Using outdoor speakers, I was unable to project the drill rig noise at the same amplitude of an actual rig, but I was able to significantly elevate the sound levels at treatment sites. The noise levels at treatment sites roughly corresponded to noise levels that can be experienced approximately 100 m from a drill rig. This distance from a drill rig is typically beyond the well pad, in habitat that is not physically disturbed. There is widespread recognition that noise, light, and other sensory disturbances can affect the behavior and physiology of wildlife. The goal of the experiment was to determine if noise alone impacted the activity levels of bats, after being separated from the other forms of disturbance at a drilling site. I projected noise at treatment sites that were not already developed, and paired these treatment sites with control sites with no added noise. I conducted this experiment in 2013 and 2014, and present the results from 20 sites each year (10 control-treatment pairs annually). </p><p> Both years, there was an overall decrease in bat activity at treatment sites, when compared to control sites. In 2013, 8 of the 10 treatment sites had lower estimated bat activity levels. In 2014, all 10 treatment sites had lower estimated activity levels, although for some control-treatment pairs there was overlap in the credible intervals. Multiple species showed signs of reduced activity at treatment sites. For both years, <i>M. ciliolabrum </i> and <i>L. cinarius</i> had reduced activity levels at treatment sites. The response of other species was more idiosyncratic, with reduced activity in one field season, and inconclusive or no response during the other year. The species that did respond to the noise treatment have very different life histories, making it difficult to generalize about how any given species may respond to noise. </p><p> Chapter 3 focuses on bat activity level trends over time during a two period cross-over experiment. The classic two-period crossover experiment consists of two treatments (i.e., treatments &lsquo;A&rsquo; and &lsquo;B&rsquo;), where each site is exposed to both treatments, and the order of the treatments is randomly assigned. For this study, &lsquo;A&rsquo; refers to no added noise, and &lsquo;B&rsquo; refers to a noise treatment consisting of the projected recording of drilling noise. A total of 12 sites were randomly assigned to the A:B sequence, and 13 sites were assigned to the B:A sequence. I acoustically monitored bat activity throughout the experiment, with particular interest in understanding the activity level dynamics post-exposure to the noise treatment. Most studies that investigate the impacts of noise on wildlife have focused on the response to noise during a noise treatment period, or noise event. Only a handful of previous studies have addressed the post-exposure period after noise ends. In these studies, noise treatments or events were relatively short in duration (a few minutes), and the corresponding recovery period was monitored over a similarly brief timeframe. My study differs in both the duration of the noise treatment (continuous noise over six days/nights), and in the duration of the post-exposure monitoring period (also six days/nights). I focused on the response of four bat species, <i>Myotis ciliolabrum, Myotis evotis, Lasiurus cinareus,</i> and <i>Taderida brasiliensis.</i> </p><p> Of the four focal species, <i>M. evotis</i> showed no substantial response to the noise treatment. The responses of <i>M. ciliolabrum</i> and <i>T. brasiliensis</i> were somewhat challenging to interpret. The overall activity levels of these species were lower during the treatment period in the A:B sequence, but they also had declining activity levels throughout the pre-exposure period. The activity patterns of <i>L. cinareus</i> provided the most convincing evidence of noise avoidance. Furthermore, <i> L. cinareus</i> activity levels did not show signs of recovery after the noise treatment ended in the B:A sequence. This suggests that after the six-day post-exposure period, there were still lingering effects of noise on <i>L. cinareus</i> activity levels. This study provides evidence that the effects of noise can linger for multiple days post-exposure. Future wildlife studies that assess periods of post-exposure could contribute meaningfully to this area of research, and aid in the development of conservation and mitigation efforts.</p>

Approved for public release; distribution is unlimited. / Acoustic propagation in the littoral regions of the world, even over short ranges, can be complex at high frequencies (>5 kHz), and applications such as underwater detection and communications suffer as a result. To this end, the Asian Seas International Acoustics Experiment (ASIAEX) was conducted with funding from the Office of Naval Research. One phase of this experiment took place from 29 May to 9 June 2001 and focused on short-range, shallow water acoustic propagation in the East China Sea. This thesis will be based on some of the measurements taken during the East China Sea experiment by a team from the Applied Physics Laboratory of the University of Washington. The environmental parameters and array geometry used in this and previous modeling work are as close as possible to the experiment. The objective of this thesis is to better understand the nature of turbulent perturbations and how they affect short-range acoustic propagation in a shallow water environment. This will include variations in total energy of the turbulence, variations in associated length scales, and variations in depth. In addition, the influence of other variable factors on signal coherence will also be examined. Most notably, variations in background sound-speed structure and source depth variability will be included. / Lieutenant Junior Grade, Turkish Navy

Underwater acoustic networks provide an interface between UUVs and surface or land-based control systems. By exploiting range data measured incidental to communications on these networks it is possible to perform underwater positioning similar to that of the satellite-based GPS program. In this thesis, several algorithms for generating position fixes from these range data are implemented, tested, and evaluated with synthetic data. The algorithms are then applied to data obtained during operations at sea. / US Nany (USN) author.

<p> This project is intended to demonstrate the current state of knowledge in the prediction of the tonal and broadband noise radiation from a Sevik rotor. The rotor measurements were made at the Virginia Tech Stability Wind Tunnel. Details of the rotor noise and flow measurements were presented by Wisda <i>et al</i>(2014) and Murray <i>et al</i>(2015) respectively. This study presents predictions based on an approach detailed by Glegg <i>et al</i>(2015) for the broadband noise generated by a rotor in an inhomogeneous flow, and compares them to measured noise radiated from the rotor at prescribed observer locations. Discrepancies between the measurements and predictions led to comprehensive study of the flow in the wind tunnel and the discovery of a vortex upstream of the rotor at low advance ratios. The study presents results of RANS simulations. The static pressure and velocity profile in the domain near the rotor&rsquo;s tip gap region were compared to measurements obtained from a pressure port array and a PIV visualization of the rotor in the wind tunnel</p>

<p> Vowel harmony has been of great interest in phonological research. It has been widely accepted that vowel harmony is a phonetically natural phenomenon, which means that it is a common pattern because it provides advantages to the speaker in articulation and to the listener in perception. </p><p> Exceptional patterns proved to be a challenge to the phonetically grounded analysis as they, by their nature, introduce phonetically disadvantageous sequences to the surface form, that consist of harmonically different vowels. Such forms are found, for example in the Finnish stem <i>tuoli</i> 'chair' or in the Hungarian suffixed form <i><b>hi:d-hoz</b></i> 'to the bridge', both word forms containing a mix of front and back vowels. There has recently been evidence shown that there might be a phonetic level explanation for some exceptional patterns, as the possibility that some vowels participating in irregular stems (like the vowel [i] in the Hungarian stem <i> hi:d</i> 'bridge' above) differ in some small phonetic detail from vowels in regular stems. The main question has not been raised, though: does this phonetic detail matter for speakers? Would they use these minor differences when they have to categorize a new word as regular or irregular?</p><p> A different recent trend in explaining morphophonological exceptionality by looking at the phonotactic regularities characteristic of classes of stems based on their morphological behavior. Studies have shown that speakers are aware of these regularities, and use them as cues when they have to decide what class a novel stem belongs to. These sublexical phonotactic regularities have already been shown to be present in some exceptional patterns vowel harmony, but many questions remain open: how is learning the static generalization linked to learning the allomorph selection facet of vowel harmony? How much does the effect of consonants on vowel harmony matter, when compared to the effect of vowel-to-vowel correspondences?</p><p> This dissertation aims to test these two ideas --- that speakers use phonetic cues and/or that they use sublexical phonotactic regularities in categorizing stems as regular or irregular --- and attempt to answer the more detailed questions, like the effect of consonantal patterns on exceptional patterns or the link between allomorph selection and static phonotactic generalizations as well. The phonetic hypothesis is tested on the Hungarian antiharmonicity pattern (stems with front vowels consistently selecting back suffixes, like in the example <i>hi:d-hoz</i> 'to the bridge' above), and the results indicate that while there may be some small phonetic differences between vowels in regular and irregular stems, speakers do not use these, or even enhanced differences when they have to categorize stems.</p><p> The sublexical hypothesis is tested and confirmed by looking at the disharmonicity pattern in Finnish. In Finnish, stems that contain both back and certain front vowels are frequent and perfectly grammatical, like in the example <i> tuoli</i> 'chair' above, while the mixing of back and some other front vowels is very rare and mostly confined to loanwords like <i>amat&oslash;&oslash;ri </i> 'amateur'. It will be seen that speakers do use sublexical phonotactic regularities to decide on the acceptability of novel stems, but certain patterns that are phonetically or phonologically more natural (vowel-to-vowel correspondences) seem to matter much more than other effects (like consonantal effects).</p><p> Finally, a computational account will be given on how exceptionality might be learned by speakers by using maximum entropy grammars available in the literature to simulate the acquisition of the Finnish disharmonicity pattern. It will be shown that in order to clearly model the overall behavior on the exact pattern, the learner has to have access not only to the lexicon, but also to the allomorph selection patterns in the language.</p>