Browsing Reprints by Title

Now showing items 405-424 of 548

    • Results from the use of broad-band, sub-bottom seismic data with statistically based sediment classification techniques 

      Simpkin, Peter G.; Collins, William T. (NATO. SACLANTCEN, 1997)
      The QTC VIEW sediment classification system has been applied to shallow, high resolution seismic data recorded with the IKB-SEISTEC profiler from the navigable channel of the St. Lawrence estuary in Canada. A number of 10 ...

    • Retrodirective array performance case studies and implications for mine countermeasures 

      Hallaj, I. M.; Kargl, Steven G.; Roy, R. A. (NATO. SACLANTCEN, 1997)
      The use of focused acoustic fields for the mechanical destruction of fluid-borne targets is applied zn. the medical field for the comminution of kidney stones by lithotripsy. Inhomogeneities in the propagation medzum are ...

    • Review of numerical models in underwater acoustics including recently developed fast-field program 

      Jensen, Finn B.; Schmidt, Henrik (NATO. SACLANTCEN, 1984/12)
      Two papers given by SACLANTCEN personnel at the NATO Advanced Research Workshop on Hybrid Formulation of Wave Propagation and Scattering at Castel Gandolfo, Rome, Italy on 30 August to 3 September 1983 are published as a ...

    • Review of target strength information for waterside security applications 

      Zampolli, Mario; Jensen, Finn B.; Tesei, Alessandra (NURC, 2008)
      Estimates of the target strength of objects, such as for example scuba tanks and swimmer delivery vehicles, are parameters of interest in all phases of the design of waterside security systems. Results of numerical target ...

    • Riverine environmental acoustics at an ocean estuary 

      Muir, Tom G.; Blue, J. E.; Anderson, A. L. (NATO. SACLANTCEN, 1997)
      The purpose of these studies was to investigate some of the more important geoacoustrc parameters that might govern the use of high frequency sonar in muddy rivers, where they flow into the sea. Both environmental and ...

    • A robust, opportunistic clock synchronization algorithm for ad hoc underwater acoustic networks 

      Vermeij, Arjan; Munafò, Andrea (CMRE, 2019/06)
      The proliferation of deployed sea-going autonomous platforms, such as autonomous underwater vehicles (AUVs), unmanned surface vehicles (USV), and sensor nodes anchored to the seabed, makes the deployment of true underwater ...

    • Role of propagation in ambient noise 

      Ross, Donald (NATO. SACLANTCEN, 1982/06)
      To be useful for modern ASW systems design and analyses, descriptions of ambient noise fields must go beyond average omnidirectional spectra and include horizontal and vertical patterns, fluctuations with time, dependencies ...

    • SACLANTCEN real-time signal processing system 

      Seynaeve, Robert; Boni, Pier Angiolo; Duarte, Vasco; McCann, Michael J.; Nesfield, Philip (NATO. SACLANTCEN, 1979/12)
      To meet its increasing requirements in real-time signal processing, SACLANTCEN has developed a general purpose. signal processing system called WARP to be uS.ed with a fairly wide range of underwater acoustic research ...

    • Scalable adaptive multitarget tracking using multiple sensors 

      Meyer, Florian; Braca, Paolo; Hlawatsch, Franz; Micheli, Michele; LePage, Kevin D. (CMRE, 2019/06)
      In networked mobile multitarget tracking systems, parameters such as detection probabilities, clutter rates, and motion model parameters are often unknown and time-varying. Such parameter variability can seriously degrade ...

    • A scalable algorithm for tracking an unknown number of targets using multiple sensors 

      Meyer, Florian; Braca, Paolo; Willett, Peter K.; Hlawatsch, Franz (CMRE, 2019/06)
      We propose an algorithm for tracking an unknown number of targets based on measurements provided by multiple sensors. Our algorithm achieves low computational complexity and excellent scalability by running belief propagation ...

    • Scalable and distributed sea port operational areas estimation from AIS data 

      Millefiori, Leonardo; Zissis, Dimitrios; Cazzanti, Luca; Arcieri, Gianfranco (CMRE, 2019/06)
      Seaports are spatial units that do not remain static over time. They are constantly in flux, evolving according to environmental and connectivity patterns both in size and operational capacity. As such any valid decision ...

    • Scalable distributed change detection and its application to maritime traffic 

      Millefiori, Leonardo; Braca, Paolo; Arcieri, Gianfranco (CMRE, 2019/06)
      Building on a novel methodology based on the Ornstein-Uhlenbeck (OU) process to perform accurate long-term predictions of future positions of ships at sea, we present a statistical approach to the detection of abrupt changes ...

    • Scattering from a random interface 

      DeSanto, John Anthony (NATO. SACLANTCEN, 1975/10)
      The problem of scattering from a random interface separating two fluids with different densities and sound speeds is considered. The method is to write coupled integral equations in coordinate space connecting the surface ...

    • Scattering from an elastic cylinder buried beneath a rough water/sediment interface 

      Fawcett, John A. (NATO. SACLANTCEN, 1997)
      In this paper a plane-wave decomposition method is used to compute the two-dimensional backscattering from a buried elastic cylinder as a function of frequency. The cases of a pat water/sediment interface and deteministically ...

    • Scoring robotic competitions: balancing judging promptness and meaningful performance evaluation 

      Ferreira, Fausto; Ferri, Gabriele; Petillot, Yvan; Liu, Xingkun; Palau Franco, Marta; Matteucci, Matteo; Perez Grau, Francisco Javier; Winfield, Alan Ft. (CMRE, 2019/05)
      To have a significant and fair competition an adequate scoring system is necessary. Different scoring systems exist, each one directly related to the nature and goals of the competition, e.g. student/educational, focused ...

    • Seabed characterization by inversion of parametric sonar data: selection of the cost function 

      Caiti, Andrea; Bergem, Oddbjorn; Pouliquen, Eric; Biancheri, A.; Scaricacciotoli, S. (NATO. SACLANTCEN, 1997)
      A class of possible cost functions to be used in model-based estimation of bottom parameters from highfrequency backscatter signals is introduced. The cost is based on the properttes of the signal in the wavelettransformed ...

    • Seabed sediment characteristics assessed geophysically: results of experiments in the Clyde Sea, Scotland 

      Davis, Angela; Haynes, Ronald; Huws, Dei (NATO. SACLANTCEN, 1997)
      Within a research programme aimed at developing in situ sediment classification methodologies, it has been demonstrated that with only limited ground truth information, sub-bottom profiler data can be inverted to produce ...

    • Seabed survey by VHR multichannel seismics: GEOSIS project 

      Meunier, J.; Dubois, J. C.; Kuhn, H.; Desvallieres, Th.; Puech, A. (NATO. SACLANTCEN, 1997)
      Site surveys prior to the installation of offshore facilities are required to obtain shallow soil structural and geotechnical information. The French project GEOSIS was aimed at improving both geophysical and geotechnical ...

    • Secure underwater acoustic networks: current and future research directions 

      Lal, Chhagan; Petroccia, Roberto; Conti, Mauro; Alves, João (CMRE, 2019/06)
      Underwater Acoustic Networks (UANs) are widely used in various applications such as climate change monitoring, pollution control and tracking, tactical surveillance and offshore exploration. However, limited consideration ...

    • Security versus defence: dual use from a system requirement perspective 

      Kessel, Ronald T. (NURC, 2008/09)
      The developers of defence technologies in both industry and national laboratories carried their culture for military system development into the evolving security mission, even for systems that are to be used by civilian ...