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OCEANS '97. MTS/IEEE Conference Proceedings

Date 6-9 Oct. 1997

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  • MTS/IEEE Conference Proceedings Oceans '97 [front matter]

    Publication Year: 1997 , Page(s): i - xx
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    Freely Available from IEEE
  • Author index

    Publication Year: 1997 , Page(s): 1507 - 1510
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  • Three dimensional visualization of oceanographic data: a case study of the Gulf of Mexico's coastal interface with Texas and Louisiana

    Publication Year: 1997
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    Summary form only given. The current state-of-the-art 3D scientific visualization, as applied to coastal ocean data, is discussed. The significance of 3D animation, videography, and virtual reality techniques, as tools for the analysis of littoral phenomena, is examined. Constraints to integrating scientific visualization within coastal ocean modeling and possible integrative solutions are identified. Subsequently, the Gulf of Mexico's coastal interface with Texas and Louisiana is presented, as a case study of temporal and spatial analysis utilizing a suite of integrated visual inputs, including remotely sensed satellite and airborne data and archival salinity, bathymetry, currents, temperature, and wave-height data. Finally, the future of 3D scientific visualization is assessed, given the imminent launch of the Earth Observing System (EOS), an array of public and private sector high-resolution satellite sensors, and advances in ocean modeling technology. Prior to the availability of advanced visualization techniques, ocean model outputs were visualized in 2D rectangular flat surfaces. In order to render such output more realistically, various techniques emerged. These included digital elevation models, wire frame overlays, and grey scale and color-shading mapping techniques. More recently, scientific visualization has benefited from the explosion of graphical advances in the fields of animation, virtual reality, and specialized grid generation, as well as increased hardware capacity for rapid rendering of imagery View full abstract»

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  • Gray-scale visualization of wave spectra in an ocean eddy

    Publication Year: 1997 , Page(s): 1203 - 1208 vol.2
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    This paper describes the application of gray-scale or sonogram display techniques to the display of time-evolving wave spectra in an ocean eddy during the passage of several weather systems. The experimental data were collected using nine Lagrangian Ambient Noise Drifting buoys (LANDs) [Risley et al., Lagrangian Ambient Noise Drifters, Proc, OCEANS '94, Vol III, p. 34-9] deployed and monitored in a warm eddy north of the Gulf Stream for two weeks in 1994. Non-directional wave-energy spectra were collected every hour along with several other related parameters, most notably wind speed and direction. Gray-scale plots are shown to provide dramatic visualization of the growth and decay of the various energy spectral components as the wind speed rises and falls at various locations in and near the eddy. Gray-scale plots are also used to highlight the spectral differences between selected buoys on opposite sides of the eddy in order to investigate the effect of water current upon the wave spectral content View full abstract»

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  • Repetitive surveys to assess sand ridge movement offshore Sable Island

    Publication Year: 1997 , Page(s): 1377 - 1393 vol.2
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    A considerable amount of seabed information has been collected over the years on the Scotian Shelf near Sable Island. The seabed around Sable Island is composed predominantly of sands and its morphology is characterized by numerous large sand ridge features and smaller megaripple fields. It has been speculated that the larger sand ridge bedforms are storm generated and are possibly moving, at least on an intermittent basis. The objective of this paper is to present comparative measurements to shed light on how much the seabed has changed over a time period of engineering significance. The fact that the top surface sands are actively mobile from storm to storm is not disputed nor is it the subject of this paper. The focus of this paper is to evaluate the change of the underlying bedforms based on repetitive surveys. In the past it was difficult to evaluate bedform migration due to navigation uncertainty and the large line spacing (and resulting low data density) of bathymetric measurements. With the availability of differential global positioning systems (DGPS) and swath bathymetry in recent years, a more accurate evaluation of sand ridge movement can now be made. Coincident swath surveys from 1995 and 1996 are compared to each other, and to various data sets from the 1980s to evaluate sand ridge movements over a maximum of 16 years. The amount of potential sand ridge movement is important to pipeline design. If the sand ridges are moving then buried pipelines may become exposed over time creating free-spans and possible pipe overstress conditions. Thus it is important to understand the magnitude of seabed migration over the design life of the pipeline View full abstract»

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  • Matched field geoacoustic tomography experiments using light bulb sound sources in the Haro Strait sea trial

    Publication Year: 1997 , Page(s): 763 - 768 vol.2
    Cited by:  Papers (1)
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    This paper describes a non-invasive low-frequency acoustic tomography experiment designed to estimate the geoacoustic properties of the ocean bottom over a large area in shallow water. The experiment was carried out in June 1996 during the Haro Strait PRIMER sea trial, a multi-purpose exercise using three vertical line arrays (VLAs) to investigate coastal ocean processes in Haro Strait. The low-frequency tomography experiment was designed to provide acoustic field data for inversion of the bottom properties, and also to acquire ground truth data for comparison with the acoustic estimates. The inversion was carried out using a coherent broadband matched field processing technique. The ground truth measurements included detailed bathymetric and subbottom surveys using differential GPS navigation, and sediment cores and grab samples. The geoacoustic tomography experiments made use of light bulbs deployed at depths from 30-70 m around and within the VLA configuration as sound sources to measure bottom reflectivity, and also to provide data for array element localization. The tomography experiments and procedures for deploying the light bulbs and the coherent broadband inversion method are described, and the estimated geoacoustic profile in the vicinity of one of the VLA sites is presented View full abstract»

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  • Seabottom roughness measurement by aquatic walking robot

    Publication Year: 1997 , Page(s): 1395 - 1398 vol.2
    Cited by:  Papers (3)
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    Port construction works in Japan are now being done in deeper sea areas than before. Flattening of the rubble mound foundation in these deeper areas are carried out by machines because human divers' working time is very short at these depths. The authors developed a six-legged aquatic walking robot for underwater inspection. The robot named “AQUAROBOT” is navigated by an LBL ultrasonic transponder on the machine-leveled rubble mound foundation at up to 50 m depth. AQUAROBOT is able to walk on the uneven surface of the mound autonomously with its several sensors. Roughness is measured by the foot motion and pressure gauge during walking. The measured data is compensated for the tide View full abstract»

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  • Conceptual re-design techniques utilised for optimisation of a mine countermeasure towed acoustic generator control system

    Publication Year: 1997 , Page(s): 1266 - 1269 vol.2
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    Acoustic replication of a surface vessel is achieved by use of an electrohydraulic towed generator emitting a range of low and audio frequency signal spectra patterns within a specified bandwidth. System performance and endurance inadequacies inherent within the design for over a decade necessitated a complex modelling and simulation exercise for key parameter identification of problematic subsystem failures. Previous system updates were based purely on experimental testing and subsequently proved ineffective when implemented. The system comprises three key areas, each with its own complex transient behaviour. These are the input transmission drive, the hydraulic actuation system and the electronic feedback control system. The complex interaction between these three subsystem could only be assessed using modern computer simulation techniques to assist experimental development. This paper describes the development and application of simulation techniques to overcome the reliability and endurance failures. The paper identifies the process involved in failure categorisation, subsystem optimisation, hardware development and results achieved. In essence, the units problems manifested itself as a destructive resonance which produced excessive pressure oscillation in the system service lines. The main system problem was initially thought to be due to the electrohydraulic actuation and feedback control system; however subsequent instrumentation to obtain torque fluctuations on the input drive to the system demonstrated that the original simulation model did not fully represent the chain of events leading to the problem. The model was improved by the addition of a complex input drive comprising four degrees of freedom with representative stiffness and backlash terms. This was shown to reproduce the observed behaviour and highlight the input drive as the prime cause of system malfunction. The simulation provided precise input drive parameter changes necessary to strengthen the drive members and thus overcome the input resonance problem View full abstract»

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  • Autonomous control system for offshore oil exploitation using digital acoustic communication

    Publication Year: 1997 , Page(s): 849 - 853 vol.2
    Cited by:  Papers (1)  |  Patents (1)
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    Underwater acoustic communication systems are the best choice to implement a cableless communication system suitable for the expected setups at subsea oil production systems. The main points at these systems are the communication reliability and the hardware reliability. Usually the control or monitoring systems could operate at a very low data rate. Typically, these acoustic systems need to operate at horizontal distances ranging from 1 to 10 km and at water depths from 100 to 2000 m. To select suitable signaling techniques in these fading multipath channels, it is fundamental to evaluate the distortions introduced in the signal by the channel. Experimental results with some of these configurations, with evaluations of time spreading, frequency spreading, frequency and time coherence and statistical distribution of the fading are presented. The multipath configuration can be evaluated by ray-tracing software. The main difficulties to implement a simple FSK system, even with a low data rate, are the multipath. A modem that can overcome the multipath and intersymbolic interference is proposed; this modem uses a FSK modulation scheme with silence intervals (guard intervals). A special symbol synchronization system is also proposed, based on the use of Williard words. Experimental results with this modem at the Brazilian Campos Basin showed promising results View full abstract»

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  • Development of the autonomous surface craft “ACES”

    Publication Year: 1997 , Page(s): 827 - 832 vol.2
    Cited by:  Papers (12)  |  Patents (4)
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    At the MIT Sea Grant College Program, Autonomous Surface Craft (ASCs) have been under development since 1993. An ASC is a small vessel outfitted with navigation and control systems which permit it to carry out functions autonomously. The first ASC developed was the ASC ARTEMIS, which was used to study command and control architectures, navigation systems, and basic data collection techniques. This vehicle successfully demonstrated the ability to operate autonomously and collect hydrographic data. ARTEMIS served well as a test platform but its small size made it unsuitable for coastal and open ocean research. Cruising speed, range, payload, and stability were all improved in the second generation ASC platform. The ASC ACES (Autonomous Coastal Exploration System) will provide better cruising speed, significantly more payload, longer mission endurance, and better seakeeping characteristics when compared to ARTEMIS. This was achieved within the primary design constraint of a 300 pound maximum weight chosen so that ACES could be easily deployed by a two member operations team. This paper describes the development of ACES. The challenge of designing a small lightweight platform with the required performance is explained and the solution implemented on ACES is described. Primary components of the design described include the hull and structural members, propulsion and power systems, and steering systems View full abstract»

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  • Error correction coding for communication in adverse underwater channels

    Publication Year: 1997 , Page(s): 854 - 861 vol.2
    Cited by:  Papers (3)
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    We address a specific implementation of frequency hopped, M-ary frequency shift keying (FH/MFSK) combined with an innovative whitening filter and very strong error correction coding. The motivation for this work is to provide reliable acoustic communications in adverse channels which may include severe fading, dynamic noise, jamming, and multi-access interference. The application addressed by this paper involves low power equipment providing robust communications while simultaneously providing low probability of detection by unauthorized interceptors View full abstract»

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  • Bird orientation effects in quantitative airborne electromagnetic interpretation of pack ice thickness sounding

    Publication Year: 1997 , Page(s): 1114 - 1119 vol.2
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    Changes in helicopter electromagnetic (HEM) bird orientation caused by bird swing occur continuously during normal surveying. These changes generate small, continuously varying errors in the measured HEM responses and in estimated bird altitude. These errors have been considered to be negligible in the past, and for small swings are certainly not critical to first-order interpretation. However, significant errors can occur during quantitative interpretation of HEM responses unless accurate estimates of bird attitude are recorded and used during interpretation. An example derived from a precision sea ice thickness survey illustrates two components of orientation-generated error. Fortunately, technological advances have simplified the acquisition of bird attitude data View full abstract»

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  • Underwater light bulb implosions: a useful acoustic source

    Publication Year: 1997 , Page(s): 755 - 762 vol.2
    Cited by:  Papers (1)  |  Patents (1)
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    The implosion of sealed glass vessels-such as fishing floats, laboratory glassware, and various bottles-under the influence of hydrostatic pressure at depth in the ocean has long been known to produce moderately loud acoustic events. Common light bulbs have also been frequently used in practice, but it appears that the use of these particular vessels has not been described in the scientific journals. In fact, most users of light bulbs have no information on the crush depths, source level, and spectral content of the radiated signal. The aim of this paper is to remedy this shortcoming, to describe the use of common light bulbs as acoustic sources, and to provide guidance to researchers on the source level, spectrum, and usage of common sizes of light bulbs and fluorescent lighting tubes. With the current focus on shallow-water operations, bearing in mind the prohibition against the use of all but the smallest explosives, imploding light bulbs may be the most cost-effective acoustic source at depths under 300 m that minimizes environmental impact View full abstract»

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  • Synthetic Environment Tactical Integration Virtual Torpedo Project

    Publication Year: 1997 , Page(s): 1431 - 1436 vol.2
    Cited by:  Patents (2)
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    Fiscal realities and a reprioritization of United States (US) military spending have demanded that all systems and capabilities be fully exploited through an effective and efficient development, testing, training and operations continuum. To the US submarine community, this has meant that the traditional isolationist culture had to change, new and novel data communications technologies were required and all available resources and technologies had to be fully exploited for development, testing, training, and operation. Until recently, however, submarine communications systems and architectures were ill equipped to handle data and communications links required to support most resource sharing. With the recent advances in submarine communications systems, the time is at hand to implement this critical element of the new US military paradigm. The Naval Undersea Warfare Center's Synthetic Environment Tactical Integration (SETI) Virtual Torpedo Project (VTP) utilizes new and innovative communications capabilities to provide a resource sharing capability to the submarine offering a high fiscal and capability payoff. VTP provides operational submarines with real-time access to high fidelity torpedo simulations of the US Navy's undersea Weapons Analysis Facility (WAF). The WAF is Hardware-In-The-Loop (HITL) facility offering extremely high fidelity torpedo engagement capability with full interactivity with the firing platform. Novel submarine communications capabilities are incorporated into VTP to allow for bi-directional data flow with up to two submarines at depth and speed. Additionally, hardware independent software (Java language) and a related downloadable client architecture are being developed to provide interoperability and reuse across the US Department of Defense (DoD) test and training infrastructure. Recent tests and demonstrations such as Synthetic Theater of War-Europe (STOW-E) have implemented the capability to intermingle real and virtual worlds. However, the utility of these synthetic environments and the ability to provide such a capability economically for day-to-day use, in an undersea domain, has yet to be demonstrated. Through the use of state of the art underwater communications systems, innovative information compression methods and a Java based Infrastructure, VTP addresses all of these issues and will provide a day-to-day virtual torpedo capability at a twenty-to-one (20:1) cost reduction over recoverable exercise torpedoes View full abstract»

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  • An application of tapered, PZT composite lenses in an acoustic imaging sonar with 1-cm resolution

    Publication Year: 1997 , Page(s): 1043 - 1047 vol.2
    Cited by:  Papers (1)  |  Patents (1)
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    This paper describes an experimental sonar with a resolution of 1 cm and a maximum range of 2.4 m. It was built to inspect hulls for fouling and damage in turbid water where optical systems fail. The system specifications called for a forward-looking sonar that could ensonify an area 0.6 m×1.5 m with 1-cm resolution. The sonar would mount on a remotely operated vehicle (ROV) that crawled systematically over the hull to assess fouling or to specific points to assess damage. The image needed to be refreshed rapidly enough that the sonar could also serve as a navigation aid for the ROV. Our solution was a mechanically scanned system with four transducers on a single shaft. The operating range and resolution allowed a refresh rate of two scans per second. The maximum range of 2.4 m allowed an operating frequency of 3 MHz, and thus a transducer aperture of only 12 cm was needed to obtain the 0.2° beamwidth. Each transducer was cut from a PZT composite. The cut transducers were given a tapered, diamond shape that significantly reduced the beampattern sidelobes in azimuth and elevation. Unfortunately, the calculated far field of the transducers was 22.6 m! The far field was shortened to 2 m by placing a plano-concave lens in front of each tapered PZT composite. The in-water electronics were connected to the surface electronics by a 150-m fiber optic cable. The system provided images with enough detail to allow the user to note individual barnacles or colonies of barnacles, peeling paint, and details on fixtures mounted on the hulls View full abstract»

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  • A robust discriminant parameter set for the underwater object classification

    Publication Year: 1997 , Page(s): 789 - 794 vol.2
    Cited by:  Papers (2)
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    The time-frequency analysis of the magnetic signals, generated by ferromagnetic objects, is used in order to find a robust discriminant parameter set for their classification. An original combination of energetic, spectral and time-scale based parameters is proposed. An excellent recognition rate and a good and regular behavior in the presence of noise are obtained. It is also proven that only a complex analysis of the acquired signals using their representations in different domains is able to lead to good results View full abstract»

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  • Detecting small seabed targets using a high frequency multibeam sonar: geometric models and test results

    Publication Year: 1997 , Page(s): 815 - 819 vol.2
    Cited by:  Papers (1)
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    The detection of small seabed targets has predominantly been achieved through the use of deep-towed side scan sonar technology. The target cannot be relied on to have distinctive backscatter strength but usually lies proud of the seabed, thus casting a shadow. Such technology fails at higher grazing angles where shadows are no longer cast. Thus repetitive, overlapping survey geometries are required to fill the “nadir gap”. An alternate technology that can detect topographic anomalies without relying on shadows is high frequency multibeam sonars (HFMS). If such systems can be combined with side scan methods, target search times can be considerably reduced. Traditionally HFMS sonars have been hull mounted and thus are not able to resolve small (<1.5 m) targets in continental shelf water depths (30-200 m). If such sonars were deployed on tow bodies however, small target detection at high grazing angles may be feasible. To this end, we have investigated the capability of one of these sonars using altitudes between 10 and 30 m (as might be achieved by mounting such a sonar on terrain-following tow fish). Our preliminary modelling suggests that the beam footprints (using 1.5 degree beam) and the beam sounding density are potentially sufficient to achieve the required objective. We identified two limiting conditions. We compared the results of our modelling with actual data taken from a small survey launch in water depths between 10 and 30 m using targets ranging in size from a few decimetres to 1.5 metres View full abstract»

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  • Analysis of wind measurements from a moored buoy

    Publication Year: 1997
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    Summary form only given. The wind data from remotely located heave-pitch-roll buoy stations operated by the National Data Buoy Center (NDBC) have both climatological and operational uses. In this study, the author investigated the wind measurements and its relation to buoy motions during severe seas. Wind data were collected from a NDBC 3-m heave-pitch-roll discus buoy during high seas caused by the Hurricane Gordon. The data were from a on-board time series data recorder that recorded measurements of wind speed, wind direction, and buoy motions. The wind speed and direction measurements were shown to be closely related to the buoy motions at frequencies higher than 0.03 Hz, which, as a result, significantly affects the 8-second gust wind speed. But the 8-minute average wind speed and direction were not affected. Depending on the wind direction and the wave direction, the wind speed measured at the peak of the wave crest could be higher or lower than that in the wave trough. This study indicated that any attempt to measure high-frequency wind turbulence near the ocean surface boundary from a moored heave-pitch-roll buoy is subject to possible distortions caused by buoy motions. The magnitude and characteristics of such effects could depend on buoy hull-mooring design, wave direction, and wind direction View full abstract»

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  • A broadband UWA communication system: based on COFDM modulation

    Publication Year: 1997 , Page(s): 862 - 869 vol.2
    Cited by:  Papers (5)
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    In this paper, a novel modulation scheme for UWA communications which uses coherent pseudo-random phase carrier COFDM modulation is presented. The new system configuration shares the advantages of the correlating receiver of the direct sequence spread spectrum (DS-SS) system and COFDM modulation. A key feature of the new system is that a pseudo-random Gaussian noise (PRGN) signal can be used as a channel sounding probe for measuring the complex channel transfer function for the frequency domain signal equalization. The PRGN signal itself can be optimized to the available dynamic range of the transmitter DAC in order to provide the best peak-to-rms ratio (or equivalently, the crest factor). Because of the unique random phase sequence used for the optimization process, synchronization can be achieved by linear cross correlation between the received signal and a known replica phase sequence in the receiver. By virtue of the frequency domain equalization and maximum likelihood Viterbi decoding, the system is shown to have high stability and can operate with low BER at extremely low SNR conditions View full abstract»

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  • GMDSS training-the impact of new technology

    Publication Year: 1997 , Page(s): 1036 - 1040 vol.2
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    This paper describes new technology applications which several manufacturers are now applying to GMDSS simulators (emergency marine radiocommunication) in order to make them more realistic and more productive in trainee throughput, while enhancing the overall quality of training. What is the end aim of GMDSS training? Essentially, it is to enable deck officers to use the complete GMDSS suite in a confident, knowledgeable manner, with minimum risk of error. It will not guarantee that false alerts will never be transmitted, but it will certainly reduce their incidence to manageable levels. As well, of course, it will bring more order and discipline to overall communications traffic, especially in distress situations. At the same time, it must be recognized that the complete GMDSS suite is a fairly formidable array of communications equipment, and complete mastery of it is a challenge. This is particularly the case with deck officers who, generally speaking, are not-and have no inclination to be-radio specialists. With the aid of new training technology, they no longer need to be View full abstract»

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  • FM pulses separation for improving sub-bottom attenuation estimation

    Publication Year: 1997 , Page(s): 1359 - 1364 vol.2
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    A new method is proposed to infer the attenuation properties of the seafloor from its response to the frequency modulated pulses emitted by the subbottom profiler. This method is based on the time-frequency separation of two chirps and the spectral ratio algorithm combined with a neural network to improve attenuation estimation for thin sediment layers View full abstract»

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  • Satellite radar scatterometer (NSCAT) studies of ocean surface stress in near coastal regions

    Publication Year: 1997
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    Summary form only given. This study addresses the consistency of the surface friction velocity derived from the scatterometer normalized radar cross section (NRCS) measurements and the directional properties of the NRCS (SIGMA-O) measurements in near coastal regions. NSCAT data (Level 1.7) colocated with numerous NDBC buoys is being analyzed to determine the variability of the directional properties of the colocated fore and aft beam measurements. These orthogonal measurements of the NRCS (25 km resolution, and converted to linear power units) by the fore and aft beams are used to calculate the Fourier series coefficients of the azimuthal model: AO and A2. The spatial variability of A2/AO, as an indication of how the azimuthal modulation varies, is being examined in the vicinity of buoys off the U.S. Atlantic coast, in the Gulf of Mexico and along the coast of California. Preliminary results show excellent agreement between the satellite derived friction velocity (u*) using the FASINEX/Weissman Ku-band model function and buoy measurements. An alternate method of estimating u* using the satellite (Level 2.0) wind speeds and a drag coefficient produce results with a wider scatter about the buoy-derived estimates of u*. Other results show some cases in which the A2/AO term is relatively constant for the 12-to-19 SIGMA-O cells that lie within the 10 square region centered about each buoy, and other situations in which the A2/AO values vary randomly and considerably even though the winds appear to be uniform. These latter situations are of strong interest, and are being studied to determine the possible causes of this variability. Under consideration are the long wave systems, atmospheric stability and surface material properties View full abstract»

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  • Acoustic seabed classification and correlation analysis of sediment properties by QTC VIEW

    Publication Year: 1997 , Page(s): 921 - 926 vol.2
    Cited by:  Papers (2)
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    A 50-kHz echo sounder and a digital waveform acquisition and seabed classification system were used to record and process echoes from embayments near southeast Vancouver Island, Canada. Each echo was preprocessed and several statistical and spectral algorithms were used to extract its characteristic patterns. The patterns were grouped into four acoustic classes. Ground truth was available from each site allowing each cluster to be associated with a seabed type. The sediment properties and acoustic classification were compared using multivariate correlation analysis. The frequency of occurrence of fine sand was found to have large negative correlation with the penetration of a free-fall penetrometer View full abstract»

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  • Model-based array processing in a fading channel

    Publication Year: 1997 , Page(s): 779 - 783 vol.2
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    Model-based processing is a method of including physical models in the processing scheme in order to enhance the performance (smaller error variance) of the processor. The method is based on a state-space approach which leads to Kalman type estimators. A major advantage of this approach is that the stochastic aspects of the problem (system and measurement noise) can be included in a natural way, thereby allowing modeling errors to be accommodated by the processor. In the case of array processing, one can consider several types of signal models. Indeed, in the case of a standard beamformer, the linear phase or time delay progression associated with a particular signal direction or “beam” implicitly assumes a plane wave model for the signal. However, the fact that the array is moving is not considered. It has been shown that the inclusion of the array motion in the proper way results in a significantly smaller variance on the bearing error, thereby providing a passive synthetic aperture effect. In this work the model-based method is applied to simulated towed array data in a fading channel. The amplitude of the signal, along with its source frequency and bearing are considered as the elements of a state vector to be estimated in a Kalman type estimation scheme. In this manner, the Kalman filter provides a recursive type of estimator, i.e. an adaptive processor which provides estimates of the relevant parameters, even when they are varying slowly in time. Results are shown where the data were generated with a random (Rayleigh) amplitude. The results show that the processor can track the amplitude variations and render high quality estimates of the bearing angle and source frequency, even at very low signal to noise ratios View full abstract»

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  • ROV simulation validation and verification

    Publication Year: 1997 , Page(s): 1064 - 1069 vol.2
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (580 KB)  

    The TRANSoM (Training for Remote Sensing and Manipulation) program, sponsored by the Office of Naval Research, is developing a Virtual Environment based training system for remotely operated vehicle (ROV) pilots. A key feature of this system is the simulation of the vehicle in the created environment. It is imperative that the simulation be of sufficient fidelity so as to provide an effective training tool for the real systems. To this end, a dynamic model has been created, which may be tailored based on individual vehicle characteristics. Currently, this simulation is being evaluated in comparison with the performance of the Imetrix Talon ROV which is being used as the basis for the training transfer tests. The performance of the actual and simulated ROV are being compared both qualitatively and quantitatively. It is important to determine the correct “look and feel” of the simulation to the user, as well as measuring the actual dynamic responses of the vehicle and simulation. Results of the testing are being incorporated into the dynamic model to refine the fidelity and flexibility of the simulation View full abstract»

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