Now showing items 212-231 of 548

    • Fast unsupervised seafloor characterization in sonar imagery using lacunarity 

      Williams, David P. (CMRE, 2019/06)
      A new unsupervised approach for characterizing seafloor in side-looking sonar imagery is proposed. The approach is based on lacunarity, which measures the pixel-intensity variation, of through-the-sensor data. No training ...
    • Flow noise interference in measurements of infrasonic ambient noise 

      Strasberg, M. (NATO. SACLANTCEN, 1982/06)
      Estimates are presented of the local noise generated at infrasonic frequencies by turbulent water flowing in the vicinity of hydrophones used for measurements of ambient noise in the sea. Three situations are discussed: a ...
    • Forward looking sonar mosaicing for mine countermeasures 

      Ferreira, Fausto; Djapic, Vladimir; Micheli, Michele; Caccia, Massimo (CMRE, 2019/06)
      Forward looking sonars (FLS) are nowadays popular for many different applications. In particular, they can be used for Automatic Target Recognition (ATR) in the context of Mine Countermeasures. Currently, ATR techniques ...
    • Fostering marine robotics through competitions: from SAUC-E to ERL Emergency 2018 

      Ferri, Gabriele; Ferreira, Fausto; Djapic, Vladimir (CMRE, 2019/05)
      Marine robotics competitions and challenges are today very popular in the robotics community. Their value mainly lies in the opportunities they provide to teams (both student and professional) for developing and testing ...
    • Fostering the use of JANUS in operationally-relevant underwater applications 

      Petroccia, Roberto; Alves, João; Zappa, Giovanni (CMRE, 2017/11)
      This paper presents the use of JANUS in operationally-relevant underwater applications. JANUS is an open, simple and robust digital coding technology currently in process to become a NATO standard. Two underwater scenarios ...
    • From data to decision: an overview of CMRE's information supply chain 

      Berni, Alessandro; Cimino, Giampaolo; Camossi, Elena; Giannecchini, Simone (CMRE, 2019/06)
      Proper data curation is a prerequisite for the creation of long-lasting value from scientific datasets and for the generation of authoritative data-driven decision support tools. Availability of detailed information on ...
    • Gamified approach in the context of situational assessment: a comparison of human factors methods 

      De Rosa, Francesca; Jousselme, Anne-Laure; De Gloria, Alessandro (CMRE, 2019/05)
      Decision support tools are increasingly common in daily tasks, with a core component of enhancing user Situational Awareness required for an informed decision. With the goal of informing the design of automated reasoners ...
    • Gas bubbles in the sea: a review and model proposals 

      Williams, Robert Bruce; Foster, Leslie A. (NATO. SACLANTCEN, 1975/10)
      The literature pertaining to both free bubbles (pt 1) and bubbles associated with fish anotomy (pt 2) is reviewed with particular emphasis on their distributions in the sea and influencing factors. An attempt is made to ...
    • Geo-spatial tactical decision aid systems: fuzzy logic for supporting decision making 

      Grasso, Raffaele; Giannecchini, Simone (NURC, 2006/08)
      Tactical decision aid systems support
    • Geoacoustic inversion using multipath pulse shape 

      Prior, Mark K.; Harrison, Chris H.; Nielsen, Peter L. (NURC, 2008/09)
      Experimental data, measured in a shallow water region of the Mediterranean Sea, are used to show that the variation of received intensity with time is well described by existing expressions [Harrison and Nielsen, J. Acoust. ...
    • Geoacoustic modeling of the seabed at higher frequencies 

      Stoll, Robert D.; Bautista, Edgar O. (NATO. SACLANTCEN, 1997)
      In propagation at higher frequencies, local fluid motion in "hidden coordinate" systems and local discontinuities due to gas bubbles and bioturbation have a perturbing effect on the wave field. To model these effects, a ...
    • Geometrical properties of underwater sound propagation 

      Jaques, A. T.; Coate, M. M.; Goodin, T. L. (NATO. SACLANTCEN, 1971/12)
    • Glider-based seabed characterization using natural-made ambient noise 

      Nielsen, Peter L.; Siderius, Martin; Muzi, Lanfranco (CMRE, 2019/06)
      Seabed characteristics (geoacoustic properties and scattering strength) are critical parameters for sonar performance predictions. However, this bottom information is considered very difficult and expensive to achieve in ...
    • Glider-based seabed characterization using natural-made ambient noise 

      Nielsen, Peter L.; Siderius, Martin; Muzi, Lanfranco (CMRE, 2019/06)
      Seabed characteristics (geoacoustic properties and scattering strength) are critical parameters for sonar performance predictions. However, this bottom information is considered very difficult and expensive to achieve in ...
    • Graphics for real-time signal-processing systems 

      McCann, Michael J. (NATO. SACLANTCEN, 1979/12)
      A graphics software package able to produce hardcopy plots of multi-channel (of the order of 100 channels) data for real-time applications is described. The system is implemented at present using a lineprinter with graphics ...
    • Hamiltonian methods in hydro-acoustic propagation 

      Koopman, Bernard Osgood (NATO. SACLANTCEN, 1971/12)
      The investigation that I wish to outline here originated in the military need of forecasting detection p r obabilities of underwater acoustic emitters, in case s in which only a somewhat general idea of the sound speed ...
    • Heterogeneous information fusion for multitarget tracking using the sum-product algorithm 

      Soldi, Giovanni; Gaglione, Domenico; Meyer, Florian; Hlawatsch, Franz; Braca, Paolo; Farina, Alfonso; Win, Moe Z. (CMRE, 2019/06)
      The sum-product algorithm (SPA) was recently shown to provide a scalable methodology for multitarget tracking (MTT) using multiple sensors. Here, we focus on another advantage of the SPA frame-work, namely, its capacity ...
    • Heterogeneous underwater networks for ASW: technology and techniques 

      Been, Robert; Hughes, David T.; Vermeij, Arjan (NURC, 2008/06)
      NATO's research and technology objectives for anti-submarine warfare (ASW) include persistent scalable heterogeneous wide-area surveillance networks for the littoral environment. Network and system design considerations ...
    • High frequency acoustic observations of Mediterranean flow into the Black Sea 

      Di Iorio, Daniela (NATO. SACLANTCEN, 1997)
      The physical behavior of Mediterranean flow entering the Black Sea through the Strat of Istanbul is described using a variety of high frequency acoustic systems. Because of the density difference between salty Meditermnean ...
    • High frequency acoustic propagation in coastal waters 

      Akal, Tuncay; Lyons, Anthony P.; Di Iorio, Daniela; Guerrini, Piero (NATO. SACLANTCEN, 1997)
      High Frequency Acoustic Propagation experiments were performed with bottom-mounted sources and receivers at different coastal sites. A measurement technique has been developed and propagation loss data have been taken using ...