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Future Directions of MASS
Published in R. Glenn Wright, Unmanned and Autonomous Ships, 2020
Side-scan Sonar creates high-resolution imagery of the sea floor and is commonly used for hydrographic survey and marine archaeology to detect objects and debris. Of particular interest to MASS operations is its ability to identify significant objects and bottom features not present on navigation charts that can be used as landmarks to supplement land and sea-based aids to navigation in determining position. This can be accomplished without having to rely on GNSS or radio-based (e.g., eLoran) electronic positioning system resources that are subject to interference, spoofing and denial of service attacks. Side-scan imaging capability is presently being integrated into relatively inexpensive ($600–$2,200) fishing and other Sonar systems that may be installed on a wide range of vessels. Even higher-resolution imagery is also available in systems ranging in cost from a few to several thousand dollars.
Modeling Location
Published in Krzysztof W. Kolodziej, Johan Hjelm, Local Positioning Systems, 2017
Krzysztof W. Kolodziej, Johan Hjelm
Hydrography, according to the Department of Defense Glossary of Mapping, Charting, and Geodetic Terms, is “the science which deals with the measurements and description of the physical features of the oceans, seas, and lakes, and their adjoining coastal areas, with particular reference to their use for navigational purposes.” Hydrographic data have an important geospatial component. Two well-known systems of feature class definitions used to describe features within the hydrographic discipline are the S-57 Object Catalog and the Feature and Attribute Coding Catalog (FACC). The S-57 Object Catalog is part of the IHO Transfer Standard for Digital Hydrographic Data, developed by the International Hydrographic Organization. The FACC is part of the Digital Geographic Exchange Standard (DIGEST) developed through an international cooperative effort by the member nations of the Digital Geographic Information Working Group (DGIWG).
Hydrographic Surveys in Tidal Rivers
Published in S.N. Ghosh, Tidal Hydraulic Engineering, 2017
A hydrographic survey usually consists of determination of the following types of data: (i) topography of the bottom, (ii) heights and times of tides and water stages and (iii) location of fixed objects for survey and navigational purposes. In general a hydrographic survey means the procedure of measuring the depth of water in a river or sea utilising a boat or survey ship as a working platform while simultaneously determining the horizontal position of the boat relative to the near-by shoreline and prominent natural or man-made objects.
Towards application of light detection and ranging sensor to traffic detection: an investigation of its built-in features and installation techniques
Published in Journal of Intelligent Transportation Systems, 2022
Junxuan Zhao, Hao Xu, Yuan Tian, Hongchao Liu
Laser is one of the major inventions of the twentieth century. With recent advancement in electronic and communication technologies, laser sensors with smaller size and higher precision have been developed. An important application of the laser is Light Detection and Ranging (LiDAR), which measures distance to a target by illuminating the target with pulsed laser light and analyzing the reflected pulses. This is a typical non-contact active measurement technique that provides digitalized three-dimensional (3D) representation of a target based on the differences in laser return times and wavelengths. High-accuracy point clouds data can be collected quickly, stably, and reliably during both daytime and nighttime (Csanyi & Toth, 2007). In the past decade, LiDAR has been widely used in remote sensing. For example, airborne LiDAR sensors are used to measure vertical structure, bulk density, base, and peak heights of forest canopy in forest industry (Ahmed et al., 2016). Bathymetric LiDAR is a technique to capture geospatial data of coastlines and shallow waters as well as creating hydrographic data (Mandlburger et al., 2015). Terrestrial LiDAR sensors are the top choice for archeological survey, landslide monitoring, coastal erosion analysis, etc. (Kromer et al., 2017; Mahmud et al., 2015; Westoby et al., 2018).
A marine spatial data infrastructure in New Zealand: a systematic review on the cost-benefits
Published in Journal of Spatial Science, 2019
Edward Griffin, Andy Coote, Joep Crompvoets
Hydrographic services gather reliable and up-to-date information vital for charts and safe navigation. Recently it has been recognised that hydrographic information goes beyond the traditional mariner and is relevant for a range of other groups and activities (Connon and Nairn 2010, International Hydrographic Organization 2011a). For example government agencies, coastal managers, engineers and scientists can use hydrographic data to benefit activities such as tourism, commercial shipping, fishing, scientific research and coastal zone management. Technological changes in ocean mapping, e.g. high-accuracy sensors available to modern-day surveys, can be used for maintaining a sufficient channel depth in ports to attract cruise ships for tourism and encourage container-ship traffic, and the data are also of sufficient quality for coastal management (Holland et al. 2016).
Monitoring volumetric fluctuations in tropical lakes and reservoirs using satellite remote sensing
Published in Lake and Reservoir Management, 2018
Tyler A. Keys, Durelle T. Scott
Sustainable management of lakes and reservoirs is becoming increasingly more important as global population and water demand increases. There are currently 117 million lakes and reservoirs greater than 0.002 km2 (2,000 m2) in the world, making up 3.7% of the Earth's land surface area (Verpoorter et al. 2014). Societal well-being depends on these surface water bodies and yet very few lakes or reservoirs are actually monitored (Alsdorf et al. 2007). Generally, hydrographic surveying of water body bathymetry is conducted via Sound Echoing and Ranging (SONAR; Yesuf et al. 2013) or bathymetric Light Detection and Ranging (LiDAR; Hilldale and Raff 2008, Skinner 2011). Unfortunately, these methods require a great deal of money, time, and labor (Peng et al. 2006). Furthermore, in situ monitoring of lakes and reservoirs is often problematic in developing nations due to the hydro-political dangers of monitoring in international basins (Hossain et al. 2007).