Browsing Institutt for marin teknikk by Title
Now showing items 2383-2402 of 3421
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On the suppression of vortex induced vibrations of circular cylinders by radial water jets
(Doktoravhandlinger ved NTNU, 1503-8181; 2003:58, Doctoral thesis, 2003)For oilfield developments in deep water, it is of utmost importance to accurately predict Vortex Induced Vibrations (VIV) of risers and free span pipelines subjected to ocean current. In order to prolong operational life ... -
On Tower Top Axial Acceleration and Drivetrain Responses in a Spar-Type Floating Wind Turbine
(Chapter; Peer reviewed, 2017)Common industrial practice for designing floating wind turbines is to set an operational limit for the tower-top axial acceleration, normally in the range of 0.2–0.3g, which is typically understood to be related to the ... -
On Uncertainty Assessment of Fatigue Damage of Propulsion Shaft Under Ice Impact
(Chapter, 2021)In this paper, the importance of maintenance of marine propulsion is discussed with specific focus on the use of condition monitoring to inform maintenance schedules. The design requirements of DNV GL for shafts expected ... -
On-Bottom Hydrodynamic Stability of Offshore Pipelines Performing 3D Analysis in SIMLA
(Master thesis, 2020)Målet med denne masteroppgaven er å utføre en 3D hydrodynamisk stabilitetsanalyse av en undervannsrørledning på sjøbunn, for å demonstrere fordelene med en 3D funksjonalitet sammenlignet med eksisterende metoder. Hydrodynamisk ... -
Onboard DC Power Systems for Hybrid Electric Ships: Simulation and Control
(Master thesis, 2018)The main contribution of this thesis is to build a complete model of the onboard DC power system for the simulation and control. The development motivation of the DC power system is for the better fuel economy to reduce ... -
Onboard Hyperspectral Classification Enables Georeferencing
(Journal article; Peer reviewed, 2023)The Norwegian University of Science and Technology (NTNU) has been building a system composed of multiple remote sensing agents for ocean observations. NTNU launched the first HYPerspectral Smallsat for Ocean observation ... -
Onboard Tuning and Uncertainty Estimation of Vessel Seakeeping Model Parameters
(Doctoral theses at NTNU;2021:356, Doctoral thesis, 2021)The accurate prediction of critical vessel motions is essential for safe and cost-efficient marine operations. Compared with the difference-frequency responses that can be compensated by mooring and dynamic positioning ... -
Onboard tuning of vessel seakeeping model parameters and sea state characteristics
(Peer reviewed; Journal article, 2021)It is essential for a safe and cost-efficient marine operation to improve the knowledge about the real-time onboard vessel conditions. This paper proposes a novel algorithm for simultaneous tuning of important vessel ... -
Online condition monitoring of floating wind turbines drivetrain by means of digital twin
(Journal article; Peer reviewed, 2021)This paper presents a digital twin (DT) condition monitoring approach for drivetrains on floating offshore wind turbines. Digital twin in this context consists of torsional dynamic model, online measurements and fatigue ... -
Online Consequence Analysis of Situational Awareness for Autonomous Vehicles
(Master thesis, 2018)The maritime industry is undergoing substantial changes with regards to autonomy, and lately important steps has been done in realizing highly autonomous vessels for industry use. This master s thesis presents a framework ... -
Online Digital Twin and a Decision Support for Safe Maneuvering of R/V Gunnerus
(Master thesis, 2023)This thesis will present the development of an online digital twin for NTNU's Research Vessel Gunnerus. Maritime digital twins are becoming a more and more prevalent technology used for the development, maintenance, and ... -
Online Optimization of a Hybrid Electric Marine Power Plant Using Mixed Integer Linear Programming
(Master thesis, 2020)Denne masteroppgaven presenterer et litteraturstudie om temaene hybrid-elektriske kraft- og fremdriftssystemer og optimalisering og regulering av hybride kraftsystemer. Komponenter, karakteristikker og reguleringslag ved ... -
Online Path Planning for Surface Vehicles Exposed to Unknown Ocean Currents Using Pseudospectral Optimal Control
(Journal article; Peer reviewed, 2016)This paper investigates the feasibility of using pseudospectral (PS) optimal control in real-time path planning for marine surface vehicles in environments where both obstacles and unknown disturbances are present. In ... -
Online reconstruction of drifting underwater ice topography: The 2D case
(Journal article; Peer reviewed, 2015)An online estimation design for a drifting two dimensional ice topography is presented. Under the assumption that the topography can be accurately represented by a truncated Fourier series, and given a moving window of ... -
Online Riks Management for MilliAmpere 2
(Master thesis, 2022)Denne rapporten gir et grunnleggende rammeverk for Dynamisk Risiko Styring (ORM) for den autonome passasjerfergen, milliAmpere 2. Den autonome passasjerfergen vil operere som en ferge i Trondheim, mellom Ravnkloa og Vestre ... -
Online risk modeling for autonomous ships with experimental results
(Master thesis, 2019)Den maritime industrien opplever i dag betydelige fremskritt i sammenheng med autonomi, noe som gjør det mulig å forbedre automatiseringsnivået rundt navigasjon og situasjonsforståelse. Autonome fartøy er et relativt nytt ... -
Online Shape Estimation of Icebergs at Sea
(Master thesis, 2015)Offshore operations in the Arctic present several challenges, such as the threat of icebergs colliding with offshore structures.This thesis will investigate methods of estimating the shape and size of iceberg keel geometries. ... -
Online wave estimation using vessel motion measurements
(Journal article; Peer reviewed, 2018)In this paper, a computationally efficient online sea state estimation algorithm is proposed for estimation of the onsite sea state. The algorithm finds the wave spectrum estimate from motion measurements in heave, roll ... -
Onset and Progression of Vortical Structures for a Surface Combatant at Drift Angles 0, 10 and 20 Degrees
(Master thesis, 2013)The onset on progression of vortical structures of the ship model DTMB 5512 (geosym of DTMB5415) has been examined for drift angles -1, 10 and 20 degrees, by means of tomographic particle image velocimetry. The drift angle ... -
Onsite Blade Exchange on a Tension-Leg Platform Floating Wind Turbine using a Self-Climbing Crane
(Master thesis, 2023)Floating offshore wind turbines offer a means to access wind resources in waters that are too deep for bottom-fixed offshore wind turbines. To operate a floating wind farm, it must be possible to perform maintenance on the ...