Papers by Eva-Marie Nosal
Advances in experimental medicine and biology, 2012
Balaenoptera acutorostrata (minke whale) is a small and elusive baleen whale that is rarely sight... more Balaenoptera acutorostrata (minke whale) is a small and elusive baleen whale that is rarely sighted in the tropical waters of the North Pacific Ocean. During winter and spring, complex sounds called” boings” are frequently detected around the Hawaiian Islands and other ...
43 44 CHAPTER 3. SEARCHING NETWORKS order to gain access to local services and data. It is appare... more 43 44 CHAPTER 3. SEARCHING NETWORKS order to gain access to local services and data. It is apparent that mobile network agents are going to undergo considerable development and become extensively used. The networked world is going to see many of these objects.
The Journal of the Acoustical Society of America, 2013
ABSTRACT RAFOS-2 has been proposed as an undersea equivalent of GPS. By using broadband source si... more ABSTRACT RAFOS-2 has been proposed as an undersea equivalent of GPS. By using broadband source signals and resolving the multipath arrival structure, long range positioning accuracy can be ~100 m as demonstrated by Van Uffelen et al., J. Acoust. Soc. Am. 133, 3444 (2013). Further improvement requires ray identification to be performed for each instantaneous position. Using the PhilSea10 experiment as a test case, we show that the range independent arrival pattern amplitude(range, depth, travel time; ray ID) can be simply parameterized. This may lead to more efficient algorithms for real time in situ navigation of mobile platforms. [Work funded by the Office of Naval Research.].
IEEE Journal of Oceanic Engineering, 2015
Grant Number: N00014-05-1-0074 (OA Graduate Traineeship for E-M Nosal)
Measurements of geoacoustic and physical properties were made of near-surface carbonate sediments... more Measurements of geoacoustic and physical properties were made of near-surface carbonate sediments at one coarse-grained site (Site 1) and one finer-grained site (Site 2) in Kaneohe Bay, Oahu. Velocity dispersion in the measured frequency range (20 - 100 kHz) was observed at both sites, with velocity increasing from 1691 to 1708 m/s at Site 1 and from 1579 to 1585 m/s at Site 2. At both sites, effective attenuation scaled linearly with frequency, increasing from 15 to 75 dB/m at Site 1 and from 22 to 62 dB/m at Site 2. Data were compared to predictions of two common sediment geoacoustic models, namely Biot-Stoll and the Grain Shearing model. In both models, two unknown parameters were varied to find best fits at each site to (1) both attenuation and velocity data, and (2) velocity data only. Both models gave similar fits. In the fits to attenuation and velocity data, both models predicted more velocity dispersion than was measured. In the fits to velocity only, both models predicted attenuation well below measured values. This can be partially attributed to scattering since the models predict intrinsic attenuation only and the abundant shell material at both sites suggests that scattering loss should be significant.
Page 1. Acoustic Seagliders in PhilSea10: Preliminary results Bruce M. Howe, Lora Van Uffelen, Ev... more Page 1. Acoustic Seagliders in PhilSea10: Preliminary results Bruce M. Howe, Lora Van Uffelen, Eva-Marie Nosal Department of Ocean and Resources Engineering University of Hawaii at Manoa Honolulu, Hawaii, USA Glenn ...
This project developed model-based 3D passive acoustic tracking methods for minke whales. It was ... more This project developed model-based 3D passive acoustic tracking methods for minke whales. It was conducted in support of ONR Award N000140910489 in which T. Norris (Bio-Waves) conducted visual surveys at PMRF and S. Martin (SPAWAR) collected acoustic data on the PMRF bottom-mounted hydrophones. In this project, these data were analyzed to detect, characterize, and track minke whale calls. A minke boing detector and 3D model-based tracker was implemented. Acoustically derived positions were compared with SPA WAR position estimates (using the MM3 2D time-of-arrival tracking method). The MM3 2D tracker gave similar boing position estimates to the 3D model-based tracker. The localized boings were within the range for which direct paths exit and for which the constant-SSP TOA method (used by MM3 2D) is expected to give reasonable position estimates. The importance of using model-based tracking to get accurate position estimates increases with the range of the animal from the hydrophones,...
2008 New Trends for Environmental Monitoring Using Passive Systems, 2008
Flood-fill algorithms are used in the ldquobucketrdquo tool of paint programs to fill connected p... more Flood-fill algorithms are used in the ldquobucketrdquo tool of paint programs to fill connected parts of a bitmap with color. They establish the area connected to a given node in a multi-dimensional array. This paper outlines the implementation a recursive flood-fill algorithm. Two elements are defined as connected if a path exists between them along which the value of all
2010 International WaterSide Security Conference, 2010
A goal of the Center for Island, Maritime, and Extreme Environment Security (CIMES) is to develop... more A goal of the Center for Island, Maritime, and Extreme Environment Security (CIMES) is to develop passive acoustic methods to monitor harbor and near-shore environments. Advantages of passive systems include source classification capabilities (since sound sources have different signatures), improved detection and tracking capabilities in cases when sonar avoidance and jamming technologies are used, the ability to monitor the environment
2013 IEEE Digital Signal Processing and Signal Processing Education Meeting (DSP/SPE), 2013
This paper proposes a new method for impulsive source separation in multi-input single-output (MI... more This paper proposes a new method for impulsive source separation in multi-input single-output (MISO) systems based on impulse spacing. The primary application of the method is the classification of click trains from multiple marine mammals. The impulse spacing can be modeled as a renewal process, so to classify sources, an algorithm is developed to maximize the likelihood of click assignment based on the impulse spacing distributions. A theoretical lower bound on the performance is derived and the algorithm shown to get reasonably close to the bound. Additionally, the algorithm is further extended for use when the impulse spacing distribution parameters are unknown. The algorithm is tested with recordings of sperm whales, and the separation is shown to be accurate.
The Journal of the Acoustical Society of America, 2014
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Papers by Eva-Marie Nosal