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Dissertations / Theses on the topic 'Distributed Acoustic Sensing (DAS)'

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1

Hu, Di. "Fully Distributed Multi-parameter Sensors Based on Acoustic Fiber Bragg Gratings." Diss., Virginia Tech, 2017. http://hdl.handle.net/10919/85112.

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A fully distributed multi-parameter acoustic sensing technology is proposed. Current fully distributed sensing techniques are exclusively based on intrinsic scatterings in optical fibers. They demonstrate long sensing span, but their limited applicable parameters (temperature and strain) and costly interrogation systems have prevented their widespread applications. A novel concept of acoustic fiber Bragg grating (AFBG) is conceived with inspiration from optical fiber Bragg grating (FBG). This AFBG structure exploits periodic spatial perturbations on an elongated waveguide to sense variations
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2

dos, Santos Maia Correa Julia. "Distributed Acoustic Sensing for Seismic Imaging and Reservoir Monitoring Applied to CO2 Geosequestration." Thesis, Curtin University, 2018. http://hdl.handle.net/20.500.11937/75668.

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The thesis is focused on the evaluation of distributed acoustic sensing (DAS) technique applied to seismic imaging and monitoring of CO2 geosequestration. It utilises the data acquired at the CO2CRC Otway site (Victoria) and the National Geosequestration Laboratory (Western Australia) to explore capabilities of the sensing technique, optimise data acquisition and processing, and compare it to other seismic sensors. Surface and downhole acquisition geometries and a range of fibre optic cables and deployment techniques were considered.
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3

Marcon, Leonardo. "Development of high performance distributed acoustic sensors based on Rayleigh backscattering." Doctoral thesis, Università degli studi di Padova, 2019. http://hdl.handle.net/11577/3423194.

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Distributed optical fiber sensing is a thriving research field that is finding practical applications in a variety of different fields including processes at extreme temperatures, security and civil engineering. The monitoring of dynamic perturbations, usually defined in the literature as distributed acoustic sensing (DAS), can be realized with excellent performance exploiting Rayleigh backscattering both in time and frequency domain. Devices implementing Rayleigh-based DAS are already commercially available. In this thesis the results of my three-year research are presented, reporting the
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Ciervo, Christopher M. "Establishing Hydraulic Connectivity in Bedrock by Measuring the Hydromechanical Response of Fractures with Distributed Acoustic Sensing (DAS)." Thesis, California State University, Long Beach, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10840951.

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<p> Fiber optic Distributed Acoustic Sensing (DAS) is based on the principles of Coherent Rayleigh Optical Time Domain Reflectometry, where light pulses are fired through an optical fiber, and photon backscatter is measured with an optical sensor. Strain in the fiber causes changes in the amplitude and phase of backscattered light. Using light&rsquo;s two-way travel time, the optical sensor measures strain at distributed points along the length of fiber. In this work, DAS was adapted to establish hydraulic connectivity in bedrock by measuring hydromechanical strain in an observation well, as p
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5

Wild, Graham. "Distributed optical fibre smart sensors for acoustic sensing in the structural health monitoring of robust aerospace vehicles." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2010. https://ro.ecu.edu.au/theses/1873.

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The use of distributed optical fibre smart sensors for the detection of acoustic signals in the Structural Health Monitoring (SHM) of robust aerospace vehicles has been demonstrated. Current distributed optical fibre sensors are multiplexed along a single fibre. Inherent problems exist with a multiplexed architecture. Two significant issues are; the possibility of fibre breakage, and the possibility of failure of the single transmitter, the single receiver, or the single processor. In a ‘smart’ architecture, the intelligence, as well as the sensors, is distributed. Hence, if destructive damage
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6

Wang, Yunjing. "Fiber-Optic Sensors for Fully-Distributed Physical, Chemical and Biological Measurement." Diss., Virginia Tech, 2013. http://hdl.handle.net/10919/19222.

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Distributed sensing is highly desirable in a wide range of civil, industrial and military applications. The current technologies for distributed sensing are mainly based on the detection of optical signals resulted from different elastic or non-elastic light-matter interactions including Rayleigh, Raman and Brillouin scattering. However, they can measure temperature or strain only to date. Therefore, there is a need for technologies that can further expand measurement parameters even to chemical and biological stimuli to fulfill different application needs. <br />This dissertation presents a f
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7

Schilke, Sven. "Importance du couplage des capteurs distribués à fibre optique dans le cadre des VSP." Thesis, Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM042/document.

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Les capteurs distribués à fibre optique (aussi nommés DAS) sont une nouvelle technologie d'acquisition sismique qui utilise des câbles traditionnels à fibre optique pour fournir une mesure de la déformation le long du câble. Ce système d'acquisition est largement utilisé dans les profils sismiques verticaux (PSV). Le couplage est un facteur clé qui a une grande influence sur la qualité des données. Alors que, pour les acquisitions PSV, les géophones sont attachés à la paroi du puits, le câble de fibre optique est soit cimenté derrière le tubage, soit attaché avec des pinces rigides au tubage o
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8

Huynh, Camille. "Real-time seismic monitoring using DAS fiber-optic instrumentation and machine learning : towards autonomous classification of natural and anthropogenic events." Electronic Thesis or Diss., Strasbourg, 2025. http://www.theses.fr/2025STRAH001.

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Ces dernières années, une nouvelle technologie basée sur l'utilisation de fibres optiques est apparue pour surveiller les événements acoustiques naturels ou anthropogéniques : la détection acoustique distribuée (Distributed Acoustic Sensing - DAS). Cette technologie innovante permet de mesurer les vibrations sismiques à très haute résolution spatiale sur des distances allant de quelques dizaines de mètres à plusieurs centaines de kilomètres. Bien que ces données soient plus volumineuses et plus complexes à traiter que celles des sismomètres traditionnels, elles offrent des perspectives promett
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9

Schilke, Sven. "Importance du couplage des capteurs distribués à fibre optique dans le cadre des VSP." Electronic Thesis or Diss., Paris Sciences et Lettres (ComUE), 2017. http://www.theses.fr/2017PSLEM042.

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Les capteurs distribués à fibre optique (aussi nommés DAS) sont une nouvelle technologie d'acquisition sismique qui utilise des câbles traditionnels à fibre optique pour fournir une mesure de la déformation le long du câble. Ce système d'acquisition est largement utilisé dans les profils sismiques verticaux (PSV). Le couplage est un facteur clé qui a une grande influence sur la qualité des données. Alors que, pour les acquisitions PSV, les géophones sont attachés à la paroi du puits, le câble de fibre optique est soit cimenté derrière le tubage, soit attaché avec des pinces rigides au tubage o
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10

Becerril, Carlos Ernesto. "Développement de la mesure acoustique distribuée (DAS) à basse fréquence pour la détection des tsunamis." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ5078.

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À ce jour, aucun système efficace d'alerte rapide aux tsunamis (TEWS pour ses initiales en anglais) n'a encore été mis en place à l'échelle mondiale. Cette situation reflète un défi proverbial dans le domaine des géosciences : Instrumenter les fonds marins du monde entier et mener des observations à long terme avec une couverture spatiale et temporelle suffisante. Un paradigme sous la forme d'une nouvelle technologie photonique a été proposé pour une surveillance véritablement multi-échelle, tout en maintenant des coûts relativement bas. La détection acoustique distribuée (DAS) utilise les fib
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11

Clement, Pierre. "Solutions aux limites des interrogateurs B-OTDR pour la surveillance d'infrastructures : augmentation de la portée de mesure et décorrélation des paramètres de température et de déformation." Electronic Thesis or Diss., Institut polytechnique de Paris, 2020. http://www.theses.fr/2020IPPAT042.

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Cette thèse porte sur l’étude des systèmes de mesure répartie de la rétrodiffusion Brillouin dans une fibre optique, que l’on nomme B-OTDR et qui sont sensibles à la température et à la déformation de la fibre. Les solutions d'interrogateurs actuelles permettent l'instrumentation de grandes infrastructures. Cependant, il existe des limites, inhérentes au phénomène physique utilisé, qui ne permettent pas d'adresser certaines applications spécifiques. Ces limites portent sur la distance de mesure maximale accessible par ces interrogateurs mais également sur la décorrélation de la mesure des para
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12

Coelho, Emanuel F. "Acoustic Sensing of Ocean Turbulence." Thesis, Monterey, California. Naval Postgraduate School, 1991. http://hdl.handle.net/10945/38241.

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Approved for public release, distribution is unlimited<br>The need for direct turbulence measurements in the upper ocean arise from widespread requirements to correctly parameterize momentum and scalar fluxes across the air/ocean interface. Until recently these observations were limited by a lack of instrumentation capable of measuring the fine-structure velocity field down to dissipation scales. The recently developed CDV package allows simultaneous sub-centimeter resolution measurements of temperature, conductivity, pressure, shear and the 3 component velocity field. As part of the developme
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13

Khacef, Yacine. "Surveillance avancée du trafic routier par détection acoustique distribuée et apprentissage profond." Electronic Thesis or Diss., Université Côte d'Azur, 2024. http://www.theses.fr/2024COAZ5070.

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La gestion du trafic urbain est un enjeu crucial pour les villes du monde entier, en raison de l'augmentation continue du nombre de véhicules. Les méthodes classiques, telles que les caméras et les boucles de détection, s'avèrent souvent inadaptées à cause de leurs coûts élevés, de la faible résolution des capteurs, et des enjeux de protection de la vie privée. Récemment, la technologie de détection acoustique distribuée (DAS) a émergé comme une solution innovante pour la surveillance du trafic. En convertissant des câbles de fibre optique en un réseau de capteurs de vibration, la technologie
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14

Malkireddy, Sivakesava Reddy. "Spectrum Sensing of acoustic OFDM signals." Thesis, Linköpings universitet, Kommunikationssystem, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-86811.

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OFDM is a fast growing technology in the area of wireless communication due to its numerous advantages and applications. The current and future technologies in the area of wireless communications like WiMAX, WiFi, LTE, MBWA and DVB-T uses the OFDM signals. The OFDM technology is applicable to the radio communication as well as the acoustic communication. Though the licensed spectrum is intended to be used only by the spectrum owners, Cognitive radio is a concept of reusing this licensed spectrum in an unlicensed manner. Cognitive radio is motivated by the measurements of spectrum utilization .
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15

Pickering, Benjamin. "Changepoint detection for acoustic sensing signals." Thesis, Lancaster University, 2016. http://eprints.lancs.ac.uk/81171/.

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This thesis considers the application of changepoint detection methodology for the analysis of acoustic sensing signals. In the first part, we propose a detection procedure for changes in the second-order structure of a univariate time series. This utilises a penalised likelihood based on Whittle’s approximation and allows for a non-linear penalty function. This procedure is subsequently used to detect changes in acoustic sensing data which correspond to external disturbances of the measuring cable. The second part shifts focus to multivariate time series, and considers the detection of change
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16

Jacquemai, Ivo. "Acoustic wireless sensing for environmental monitoring." Thesis, Edith Cowan University, Research Online, Perth, Western Australia, 2011. https://ro.ecu.edu.au/theses/395.

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The European House Borer (EHB) is a timber pest which attacks dead timber. This pest can cause large scale damage to wooden structures and has already spread throughout many parts of the world. The larvae usually remains undetected for many years while it busily inflicts irrevocable and substantial harm to the timber. Since the pest was first discovered in Western Australia in 2004 the Government has endeavoured to extinguish its existence. In this research, an electronic sensor has been developed in order to detect the presence of EHB larvae in timber. Only an accurate detection can allow for
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17

Sundman, Dennis. "Greedy Algorithms for Distributed Compressed Sensing." Doctoral thesis, KTH, Kommunikationsteori, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-144907.

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Compressed sensing (CS) is a recently invented sub-sampling technique that utilizes sparsity in full signals. Most natural signals possess this sparsity property. From a sub-sampled vector, some CS reconstruction algorithm is used to recover the full signal. One class of reconstruction algorithms is formed by the greedy pursuit, or simply greedy, algorithms, which is popular due to low complexity and good performance. Meanwhile, in sensor networks, sensor nodes monitor natural data for estimation or detection. One application of sensor networking is in cognitive radio networks, where sensor no
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18

Kelly, Devin WW. "A Practical Distributed Spectrum Sensing System." Digital WPI, 2011. https://digitalcommons.wpi.edu/etd-theses/378.

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As the demand for wireless communication systems grows, the need for spectrum grows accordingly. However, a large portion of the usable spectrum has already been exclusively licensed to various entities. This exclusive allocation method encourages spectrum to be left unused if the licensee has no need for that spectrum. In order to better utilize spectrum and formulate new approaches for greater spectrum use efficiency, it is imperative to possess a thorough understanding about how wireless spectrum behaves over time, frequency, and space. In this thesis, a practical, scalable, and low-cos
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19

McGonigle, Chris. "Mapping benthic habitat using acoustic remote sensing." Thesis, University of Ulster, 2010. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.551582.

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Backscatter imagery from multibeam echosounders (MBES) is increasingly used for benthic habitat mapping. This research explores MBES backscatter classification using QTC-Multiview on data from Stanton Banks (UK) and Cashes Ledge (USA). Image-processing algorithms are used to extract values from samples of backscatter data, which are reduced by principal components analysis and are objectively clustered. This process is initially evaluated using 2005 data from Stanton Banks and compared with ground-truth data to determine their biological validity. Low-levels of agreement are observed between a
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20

Kloser, Rudolf J. "Seabed biotope characterisation based on acoustic sensing." Thesis, Curtin University, 2007. http://hdl.handle.net/20.500.11937/524.

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The background to this thesis is Australia’s Oceans Policy, which aims to develop an integrated and ecosystem-based approach to planning and management. An important part of this approach is the identification of natural regions in regional marine planning, for example by establishing marine protected areas for biodiversity conservation. These natural regions will need to be identified on a range of scales for different planning and management actions. The scale of the investigation reported in this thesis is applicable to spatial management at 1 km to 10 km scale and monitoring impacts at the
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21

Kloser, Rudolf J. "Seabed biotope characterisation based on acoustic sensing." Curtin University of Technology, Faculty of Science and Engineering, Department of Imaging and Applied Physics, 2007. http://espace.library.curtin.edu.au:80/R/?func=dbin-jump-full&object_id=18566.

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The background to this thesis is Australia’s Oceans Policy, which aims to develop an integrated and ecosystem-based approach to planning and management. An important part of this approach is the identification of natural regions in regional marine planning, for example by establishing marine protected areas for biodiversity conservation. These natural regions will need to be identified on a range of scales for different planning and management actions. The scale of the investigation reported in this thesis is applicable to spatial management at 1 km to 10 km scale and monitoring impacts at the
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22

Bohner, Christopher George 1972. "A distributed approach to underwater acoustic communications." Thesis, Massachusetts Institute of Technology, 2003. http://hdl.handle.net/1721.1/91806.

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Thesis (S.M.)--Joint Program in Applied Ocean Science and Engineering (Massachusetts Institute of Technology, Dept. of Ocean Engineering; and, the Woods Hole Oceanographic Institution), 2003.<br>Includes bibliographical references (p. 118-120).<br>by Christopher George Bohner.<br>S.M.
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23

Khalid, Muhammad Arslan. "Engineering surface acoustic wave sensing and diagnostic devices." Thesis, University of Glasgow, 2017. http://theses.gla.ac.uk/30999/.

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Globally, over 50% of deaths occur due to the top 10 global diseases which include cardiovascular disease, cancer and infectious diseases. Low and middle-income countries (LMICs) are disproportionately affected. 80% of all deaths due to non-communicable diseases occur in low and middle income countries and with numbers on the rise. In these disadvantaged and vulnerable populations, diseases are often detected late. The treatment required is therefore increasingly extensive and expensive. Early detection, treatment and monitoring coupled with life-style changes can reduce mortality and morbidit
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Prasad, Abhinav. "Bulk-acoustic micromechanical resonator platforms for interfacial sensing." Thesis, University of Cambridge, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.708654.

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25

Clark, Robert L. Jr. "Advanced sensing techniques for active structural acoustic control." Diss., Virginia Tech, 1992. http://hdl.handle.net/10919/37880.

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This study presents a basis for the analytical and experimental procedures as well as design techniques required in achieving adaptive structures for active structural acoustic control (ASAC). Test structures studied in this work included a baffled simply supported beam and a baffled simply supported plate which were subjected to a harmonic input disturbance created physically with a shaker and modelled by a point force input. Structural acoustic control was achieved with piezoelectric actuators bonded to the surface of the test structure. The primary focus of this work was devoted to studying
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Clark, Robert L. "Advanced sensing techniques for active structural acoustic control /." This resource online, 1992. http://scholar.lib.vt.edu/theses/available/etd-05222007-091351/.

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27

Sternlicht, Daniel D. "High frequency acoustic remote sensing of seafloor characteristics /." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 1999. http://wwwlib.umi.com/cr/ucsd/fullcit?p9935453.

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28

Feced, Ricardo. "Nonlinear techniques for distributed optical fibre sensing." Thesis, King's College London (University of London), 1998. https://kclpure.kcl.ac.uk/portal/en/theses/nonlinear-techniques-for-distributed-optical-fibre-sensing(48661ada-da47-4da7-b6db-fc995f840603).html.

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29

Dhliwayo, Jabulani. "Stimulated Brillouin scattering for distributed temperature sensing." Thesis, University of Kent, 1997. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.242858.

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30

Frazier, Janay Amber Wright. "High-Definition Raman-based Distributed Temperature Sensing." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/95934.

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Distributed Temperature Sensing (DTS) has been used in a variety of different applications. Its ability to detect temperature fluctuations along fiber optic lines that stretch for several kilometers has made it a popular topic in various fields of science, engineering, and technology. From pre-fire detection to ecological monitoring, DTS has taken a vital role in scientific research. DTS uses the principle of backscattering by three different spectral components, e.g., Rayleigh scattering, Brillouin scattering, and Raman scattering. Although there have been various improvements to DTS, its slo
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31

Hahn, Matthew J. "Undersea navigation via a distributed acoustic communications network." Thesis, Monterey, Calif. : Springfield, Va. : Naval Postgraduate School ; Available from National Technical Information Service, 2005. http://library.nps.navy.mil/uhtbin/hyperion/05Jun%5FHahn%5FMatthew.pdf.

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32

Ali, Andreas Mantik. "Distributed acoustic localization and tracking design and analysis." Diss., Restricted to subscribing institutions, 2010. http://proquest.umi.com/pqdweb?did=2023768071&sid=1&Fmt=2&clientId=1564&RQT=309&VName=PQD.

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Jain, Ankita Deepak. "Instantaneous continental-shelf scale sensing of cod with Ocean Acoustic Waveguide Remote Sensing (OAWRS)." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/100125.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2015.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 259-278).<br>Reported declines in the population of Atlantic cod have a potential to affect long-term ecological balance and the sustainability of the cod fishery along the US northeast coast. These assessments have led to severe fishing cuts over the past few years, have consequently threatened the centuries-old Atlantic cod fishery along the New England coast and put the livelihood of thousands of fishermen a
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Srinivasan, krishnan. "Nanomaterial sensing layer based surface acoustic wave hydrogen sensors." [Tampa, Fla.] : University of South Florida, 2005. http://purl.fcla.edu/fcla/etd/SFE0001325.

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Schuler, Leo Pius. "Wireless identification and sensing using surface acoustic wave devices." Thesis, University of Canterbury. Electrical Engineering, 2003. http://hdl.handle.net/10092/1081.

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Wireless Surface Acoustic Wave (SAW) devices were fabricated and tested using planar Lithium Niobate (LiNbO₃) as substrate. The working frequencies were in the 180 MHz and 360 MHz range. Using a network analyser, the devices were interrogated with a wireless range of more than 2 metres. Trials with Electron Beam Lithography (EBL) to fabricate SAW devices working in the 2450 MHz with a calculated feature size of 350 nm are discussed. Charging problems became evident as LiNbO₃ is a strong piezoelectric and pyroelectric material. Various attempts were undertaken to neutralise the charging problem
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Schuler, Leo P. "Wireless identification and sensing using surface acoustic wave devices." Thesis, University of Canterbury. Engineering, 2003. http://hdl.handle.net/10092/8565.

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Wireless Surface Acoustic Wave (SAW) devices were fabricated and tested using planar Lithium Niobate (LiNbO₃) as substrate. The working frequencies were in the 180 MHz and 360 MHz range. Using a network analyser, the devices were interrogated with a wireless range of more than 2 metres. Trials with Electron Beam Lithography (EBL) to fabricate SAW devices working in the 2450 MHz with a calculated feature size of 350 nm are discussed. Charging problems became evident as LiNbO₃ is a strong piezoelectric and pyroelectric material. Various attempts were undertaken to neutralise the charging problem
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37

Radzicki, Vincent, and Koki Matsuura. "Passive Acoustic Sensing for the Assessment of Knee Conditions." International Foundation for Telemetering, 2015. http://hdl.handle.net/10150/596462.

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ITC/USA 2015 Conference Proceedings / The Fifty-First Annual International Telemetering Conference and Technical Exhibition / October 26-29, 2015 / Bally's Hotel & Convention Center, Las Vegas, NV<br>Early detection and diagnosis of knee related health disease is critical in mitigating the long term health risks of such ailments. Passive acoustic sensing is an under-utilized monitoring system that can be used in the assessment and potential diagnosis of knee health that has many potential benefits when compared to current medical technology. Developing accurate acoustic models and procedures f
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Maillard, Julien. "Advanced Time Domain Sensing For Active Structural Acoustic Control." Diss., Virginia Tech, 1997. http://hdl.handle.net/10919/30335.

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Active control of sound radiation from vibrating structures has been an area of much research in the past decade. In Active Structural Acoustic Control (ASAC), the minimization of sound radiation is achieved by modifying the response of the structure through structural inputs rather than by exciting the acoustic medium (Active Noise Control, ANC). The ASAC technique often produces global far-field sound attenuation with relatively few actuators as compared to ANC. The structural control inputs of ASAC systems are usually constructed adaptively in the time domain based on a number of error sign
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Ferreira, Ricardo Xavier da Graça. "Acoustic optical modulation in optical fibre for sensing applications." Master's thesis, Universidade de Aveiro, 2013. http://hdl.handle.net/10773/11646.

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Mestrado em Engenharia Física<br>O presente trabalho teve como objetivo desenvolver um sensor de fibra óptica intrínseco para viscosidade com base no efeito acústoótico aplicado em redes de Bragg. Foram utilizadas fibras de silica e poliméricas para medições com baseadas no espectro e no tempo de resposta da rede quanto sujeitas ao efeito acústo-ótico. O resultado é um viscosímetro multi-paramétrico com um distinto potencial futuro. Com base no conhecimento adquirido, é proposto um novo design e mecanismo de detecção.<br>The present work aimed to develop an intrinsic optical fibre senso
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Srinivasan, Krishnan. "Nanomaterial Sensing Layer Based Surface Acoustic Wave Hydrogen Sensors." Scholar Commons, 2005. https://scholarcommons.usf.edu/etd/873.

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This thesis addresses the design and use of suitable nanomaterials and surface acoustic wave sensors for hydrogen detection and sensing. Nanotechnology is aimed at design and synthesis of novel nanoscale materials. These materials could find uses in the design of optical, biomedical and electronic devices. One such example of a nanoscale biological system is a virus. Viruses have been given a lot of attention for assembly of nanoelectronic materials. The tobacco mosaic virus (TMV) used in this research represents an inexpensive and renewable biotemplate that can be easily functionalized for th
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Hole, Erik Lillebø. "Optical Fiber sensing of acoustic waves using overlapping FBGs." Thesis, Mittuniversitetet, Institutionen för elektronikkonstruktion, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:miun:diva-37779.

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The objective of this thesis was to investigate if an optical fiber sensing method with the use of two overlapping fiber Bragg gratings to measure Lamb wave $S_0$ modes in a steel plate, and how it would compare to traditional PZT transducers. A solution was proposed where the use of an optical fiber sensing system was built and took advantage of the strain dependence of a fiber Bragg grating mounted to a steel plate. Together with an overlapping reference fiber Bragg grating, the system can translate strain to light intensity. A method of controlling the Bragg wavelength of the reference fibe
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42

Wimmer, Jason D. "Acoustic sensing: Roles and applications in monitoring avian biodiversity." Thesis, Queensland University of Technology, 2015. https://eprints.qut.edu.au/84852/9/Jason_Wimmer_Thesis.pdf.

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This thesis examined the use of acoustic sensors for monitoring avian biodiversity. Acoustic sensors have the potential to significantly increase the spatial and temporal scale of ecological observations, however acoustic recordings of the environment can be opaque and complex. This thesis developed methods for analysing large volumes of acoustic data to maximise the detection of bird species, and compared the results of acoustic sensor biodiversity surveys with traditional bird survey techniques.
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43

Read, Tom Oliver Trevett. "Applications of distributed temperature sensing in subsurface hydrology." Thesis, University of East Anglia, 2016. https://ueaeprints.uea.ac.uk/59401/.

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In the study of dynamic subsurface processes there is a need to monitor temperature and groundwater fluxes efficiently in both time and space. Distributed Temperature Sensing has recently become more accessible to researchers in Earth Sciences, and allows temperatures to be measured simultaneously, at small intervals, and over large distances along fibre optic cables. The capability of DTS in conjunction with heat injection to detect groundwater fluxes, is assessed in this thesis using a combination of numerical modelling, laboratory tests, and field trials at the Ploemeur research site in Bri
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Li, Xiaowei. "A weighted ℓ₁-minimization for distributed compressive sensing". Thesis, University of British Columbia, 2015. http://hdl.handle.net/2429/54836.

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Distributed Compressive Sensing (DCS) studies the recovery of jointly sparse signals. Compared to separate recovery, the joint recovery algorithms in DCS are usually more effective as they make use of the joint sparsity. In this thesis, we study a weighted ℓ₁-minimization algorithm for the joint sparsity model JSM-1 proposed by Baron et al. Our analysis gives a sufficient null space property for the joint sparse recovery. Furthermore, this property can be extended to stable and robust settings. We also presents some numerical experiments for this algorithm.<br>Science, Faculty of<br>Mathematic
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Mohamad, Hisham. "Distributed optical fibre strain sensing of geotechnical structures." Thesis, University of Cambridge, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.612416.

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46

Liu, Bo. "Sapphire Fiber-based Distributed High-temperature Sensing System." Diss., Virginia Tech, 2016. http://hdl.handle.net/10919/82741.

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From the monitoring of deep ocean conditions to the imaging and exploration of the vast universe, optical sensors are playing a unique, critical role in all areas of scientific research. Optical fiber sensors, in particular, are not only widely used in daily life such as for medical inspection, structural health monitoring, and environmental surveillance, but also in high-tech, high-security applications such as missile guidance or monitoring of aircraft engines and structures. Measurements of physical parameters are required in harsh environments including high pressure, high temperature, hig
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Xu, Yong Tai Yu-Chong. "Flexible MEMS skin technology for distributed fluidic sensing /." Diss., Pasadena, Calif. : California Institute of Technology, 2002. http://resolver.caltech.edu/CaltechETD:etd-12302004-144248.

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48

Chakraborty, Rupayan. "Acoustic event detection and localization using distributed microphone arrays." Doctoral thesis, Universitat Politècnica de Catalunya, 2013. http://hdl.handle.net/10803/134364.

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Automatic acoustic scene analysis is a complex task that involves several functionalities: detection (time), localization (space), separation, recognition, etc. This thesis focuses on both acoustic event detection (AED) and acoustic source localization (ASL), when several sources may be simultaneously present in a room. In particular, the experimentation work is carried out with a meeting-room scenario. Unlike previous works that either employed models of all possible sound combinations or additionally used video signals, in this thesis, the time overlapping sound problem is tackled by exploit
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Egger, Sean Robert. "A Turbo Approach to Distributed Acoustic Detection and Estimation." Thesis, Virginia Tech, 2009. http://hdl.handle.net/10919/35866.

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Networked, multi-sensor array systems have proven to be advantageous in the sensor world. A large amount of research has been conducted with these systems, with a main interest in data fusion. Intelligently processing the large amounts of data collected by these systems is required in order to fully utilize the benefits of a multi-sensor array system. A robust but flexible simulation environment would provide a platform for accurately comparing current and future data fusion theories. This thesis proposes a simulator model for testing fusion theories for these acoustic multi-sensor networks.
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Wang, Jing. "Distributed Pressure and Temperature Sensing Based on Stimulated Brillouin Scattering." Thesis, Virginia Tech, 2013. http://hdl.handle.net/10919/78066.

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Brillouin scattering has been verified to be an effective mechanism in temperature and strain sensing. This kind of sensors can be applied to civil structural monitoring of pipelines, railroads, and other industries for disaster prevention. This thesis first presents a novel fiber sensing scheme for long-span fully-distributed pressure measurement based on Brillouin scattering in a side-hole fiber. After that, it demonstrates that Brillouin frequency keeps linear relation with temperature up to 1000°C; Brillouin scattering is a promising mechanism in high temperature distributed sensing. A sid
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