Blar i NTNU Open på forfatter "Sørensen, Asgeir Johan"

Viser treff 101-120 av 130

    • Sea floor geometry approximation and altitude Control of ROVs 

      Dukan, Fredrik; Sørensen, Asgeir Johan (Journal article; Peer reviewed, 2014)
      This paper presents a method for sea floor geometry approximation in a local region beneath a remotely operated vehicle (ROV) for use in altitude control. The method is based on Doppler velocity log (DVL) altitude measurements ...

    • Sea state estimation using model-scale DP measurements 

      Brodtkorb, Astrid H.; Nielsen, Ulrik Dam; Sørensen, Asgeir Johan (Chapter, 2015)
      Complex marine operations are moving further from shore, into deeper waters, and harsher environments. The operating hours of a vessel are weather dependent, and good knowledge of the prevailing weather conditions may ...

    • Sea state estimation using multiple ships simultaneously as sailing wave buoys 

      Nielsen, Ulrik Dam; Brodtkorb, Astrid H.; Sørensen, Asgeir Johan (Journal article; Peer reviewed, 2019)
      The article presents initial ideas towards a network-based approach for sea state estimation used for marine operations and other maritime applications. In principle, all available means, ranging from in situ buoys, fleet ...

    • Sea State Estimation Using Quadratic Discriminant Analysis and Partial Least Squares Regression 

      Arneson, Ina Bjørkum; Brodtkorb, Astrid H.; Sørensen, Asgeir Johan (Journal article; Peer reviewed, 2019)
      This paper proposes non-model based sea state estimation methods for a dynamically positioned vessel. Sea state estimation entails finding the wave direction, significant wave height and peak wave period and is done based ...

    • Sea state estimation using vessel response in dynamic positioning 

      Brodtkorb, Astrid H.; Nielsen, Ulrik Dam; Sørensen, Asgeir Johan (Journal article; Peer reviewed, 2018)
      This paper presents a novel method for estimating the sea state parameters based on the heave, roll and pitch response of a vessel conducting station keeping automatically by a dynamic positioning (DP) system, i.e., without ...

    • Sensor-based Hybrid Observer for Dynamic Positioning 

      Brodtkorb, Astrid H.; Teel, Andrew R.; Sørensen, Asgeir Johan (Chapter, 2015)
      Observers are important components of dynamic positioning (DP) systems for marine vessels, estimating unmeasured states, filtering noise, filtering out wave induced motions, and predicting states in the case of signal loss. ...

    • Sensor-Carrying Platforms 

      Sørensen, Asgeir Johan; Ludvigsen, Martin; Norgren, Petter; Ødegård, Øyvind; Cottier, Finlo Robert (Chapter, 2020)
      Information and communication technology, autonomy, and miniaturization in terms of, for example, microelectromechanical systems are enabling technologies with significant impact on the development of sensors, sensor-carrying ...

    • Simulator and Control System Design for a Free Floating Surface Effect Ship at Zero Vessel Speed 

      Auestad, Øyvind Fidje; Gravdahl, Jan Tommy; Sørensen, Asgeir Johan; Halvorsen, Trygve Espeland (Journal article; Peer reviewed, 2013)
      This paper covers vertical motion damping of a free floating Surface Effect Ship (SES) at zero vessel speed. Vertical motion damping is requested at the bow deck of the SES during offshore wind turbine docking operation. ...

    • Site-specific controller design for monopile offshore wind turbines 

      Smilden, Emil; Bachynski, Erin Elizabeth; Sørensen, Asgeir Johan; Amdahl, Jørgen (Journal article; Peer reviewed, 2018)
      The fatigue life of offshore wind turbine (OWT) support structures is sensitive to variations in site-specific conditions such as the water depth and soil properties. Site condtions may vary significantly within a wind ...

    • State-of-the-Art on Artificial Intelligence for Risk-based Decision-making in Autonomous Marine Vehicles 

      Maidana, Renan Guedes; Utne, Ingrid Bouwer; Sørensen, Asgeir Johan (Chapter, 2020)
      Risk assessment (i.e., risk analysis and risk evaluation) is routinely performed in marine operations by vessel crews to inform and support the decision-making process for the ship’s operations. With the inevitable ubiquity ...

    • Stochastic, Dynamic Analysis of Offshore Wind Turbines 

      Sørum, Stian Høegh (Master thesis, 2017)
      In the last 25 years, offshore wind turbines (OWTs) have moved from small machines of less that 500 kW in a few metres of water to large multi-megawatt machines in water depths exceeding 30 meters. On monopile foundations, ...

    • Study of Critical Imaging Parameters and Variables for Environmental Monitoring Using an ROV with Experimental Results 

      Lohne, Paal Øvrebø (Master thesis, 2013)
      In the oil and gas industry there is a high focus on integrating technology in the environmental monitoring happening before, during and after an offshore operation. In order to properly monitor the underwater environment, ...

    • Study of Critical Imaging Parameters and Variables for Environmental Monitoring Using an ROV with Experimental Results 

      Lohne, Paal Øvrebø (Master thesis, 2013)
      In the oil and gas industry there is a high focus on integrating technology in the environmental monitoring happening before, during and after an offshore operation. In order to properly monitor the underwater environment, ...

    • Thrust Losses on Underwater Snake Robots with Thrusters 

      Galta, Mari Gilje (Master thesis, 2017)
      The main motivation behind this thesis is to study the effects from different thrust losses on an underwater snake robot (USR) with thrusters. In-line velocity fluctuations, transverse velocity fluctuations, thruster-thruster ...

    • Towards contract-based verification for autonomous vessels 

      Smogeli, Øyvind Rasmussen; Glomsrud, Jon Arne; Utne, Ingrid Bouwer; Sørensen, Asgeir Johan (Peer reviewed; Journal article, 2023)
      Design and verification of autonomous vessels represent a major interdisciplinary engineering challenge due to the combination of high system complexity and the interaction with dynamic, uncertain, and unstructured ...

    • Towards Robust Autonomy of Underwater Vehicles in Arctic Operations 

      Bremnes, Jens Einar (Master thesis, 2019)
      Denne masteroppgaven undersøker verktøy og metoder for å utvikle mer robuste autonomiløsninger for autonome undervannsfarkoster (AUV) i arktiske underisoperasjoner. AUVer er effektive plattformer for tverrfaglig vitenskapelig ...

    • Towards Safer, Smarter and Greener Ships Using Hybrid Marine Power Plants 

      Sørensen, Asgeir Johan; Skjetne, Roger; Bø, Torstein Ingebrigtsen; Miyazaki, Michel Rejani; Johansen, Tor Arne; Utne, Ingrid Bouwer; Pedersen, Eilif (Journal article; Peer reviewed, 2017)
      This chapter gives an overview of research activities carried out at NTNU AMOS in relation to hybrid marine power plants enabling safer, smarter and greener ships. Recently electrical power plants with a set of diesel-generator ...

    • Towards supervisory risk control of autonomous ships 

      Utne, Ingrid Bouwer; Rokseth, Børge; Sørensen, Asgeir Johan; Vinnem, Jan Erik (Peer reviewed; Journal article, 2020)
      The objective of this paper is to outline a framework for online risk modelling for autonomous ships. There is a clear trend towards increased autonomy and intelligence in ships because it enables new functionality, as ...

    • Trajectory Tracking Motion Control System for Observation Class ROVs 

      Fernandes, Daniel de Almeida; Sørensen, Asgeir Johan; Donha, Decio C. (Journal article, 2013)
      This paper proposes a MCS (Motion Control System) with trajectory tracking capability for observation class ROVs (Remotely Operated Vehicle) used to carry out automated high-resolution image capturing missions, e.g. ...

    • Underwater Hyperspectral Imaging as a Tool for Benthic Habitat Mapping 

      Mogstad, Aksel Alstad (Doctoral theses at NTNU;2021:271, Doctoral thesis, 2021)
      Since the 1950s, continuous technological advances have gradually improved our ability to map the seafloor and its associated benthic habitats. Historically, seafloor mapping has largely been carried out acoustically, using ...