Background and activities
Currently, I am a full professor on marine structures at the Department of Marine Technology, Norwegian University of Science and Technology (NTNU). I am also affiliated with Centre for Autonomous Marine Operations and Systems (SFF AMOS), Centre for Marine Operations in Virtual Environments (SFI MOVE), Centre for Floating Structures for the Next Generation Ocean Industries (SFI BLUES), Norwegian Research Centre on Wind Energy (FME NorthWind).
I obtained my bachelor and MSc degrees in Naval Architecture and Ocean Engineering from Shanghai Jiao Tong University (SJTU) in China in 2000 and 2003, respectively. My MSc study focused on numerical simulations of ship-ship and ship-bridge collisions. The thesis title is "Numerical Simulation of Ship Collision and Study on Crashworthiness of FPSO's Side Structures". My supervisor was Professor Yongning Gu.
I obtained my PhD degree at NTNU on Marine Technology in 2008, with the thesis entitled "Stochastic Response Analysis of Mooring Systems with Emphasis on Frequency-domain Analysis of Fatigue due to Wide-band Response Processes". My PhD supervisor was Professor Torgeir Moan.
From 2008 to 2015, I was employed as a post-doc, a reseacher and then an adjunct associate professor at NTNU, before I became a full professor in July 2015.
RESEARCH FIELDS AND INTERESTS
Offshore Renewable Energy: numerical and experimental study of offshore wind turbines (both bottom-fixed and floating), wave energy converters (oscillating bodies and overtopping devices), tidal turbines and combined concepts; integrated methods for global dynamic load and response analysis of offshore wind turbines; hierarchical methods for local response analysis of wind turbine drivetrains; design and analysis of floating structures to support large-scale (5-15 MW) wind turbines; modeling and analysis of offshore wind turbines with geared drivetrain, direct drive and hydraulic transmission; mooring system design and analysis for offshore renewable energy platforms, including shallow waters.
Marine Operations: operational and safety criteria for marine operations related to offshore wind turbine transport, installation and access for maintenance and repair; numerical modeling and time-domain simulation of installation operation for offshore wind turbine components (such as crane operations for installing wind turbine blades, monopile, jacket and spar foundations); weather window and operability assessment using response-based criteria; assessment of uncertainties in numerical modelling and weather forecast and their effects on decision-making for marine operations.
Structural Mechanics and Dynamics: dynamic analysis of offshore structures using finite element methods; coupled mooring analysis; fatigue assessment of offshore structures; numerical simulation of ship collision and grounding.
Stochastic Analysis: frequency-domain cycle counting methods for fatigue analysis of wide-band processes; extreme value prediction and fatigue analysis of non-Gaussian processes; stochastic modeling of random waves, including spatially inhomogeneous waves; short-term and long-term statistics of wind and waves and their induced loads/responses; contour line or surface methods for long-term extreme responses of marine structures under separate or simultaneous wind and wave loads.
Reliability and Risk Analysis: uncertainty modeling and structural reliability assessment of offshore oil and gas platforms as well as renewable energy platforms; fatigue reliability methods applied to mechanical components (such as gearbox in wind turbines); fatigue reliability analysis of offshore wind turbine foundations (such as jacket) for inspection and maintenance planning; overload and fatigue reliability of mooring system.
Machine Learning Approaches and Data-driven Models Applied in Marine Technology: forecast of short-term (1-hour to 1-day ahead) wind and wave conditions using machine-learning approaches for decision-making for execution of marine operations; forecasting of short-term (1-3 wave periods ahead) motions of vessels and wave energy converters for control purpose; machine learning approaches for fault/failure detection and diagnosis for wind turbine drivetrain/blade pitch actuator and marine structural components (such as mooring lines).
Scientific, academic and artistic work
Displaying a selection of activities. See all publications in the database
- (2021) Assessment of inhomogeneity in environmental conditions in a Norwegian fjord for design of floating bridges. Ocean Engineering. vol. 220.
- (2021) Fault detection and diagnosis of a blade pitch system in a floating wind turbine based on Kalman filters and artificial neural networks. Renewable Energy. vol. 169.
- (2021) Frequency domain modelling of a coupled system of floating structure and mooring Lines: An application to a wave energy converter. Ocean Engineering. vol. 220.
- (2021) Design and comparative analysis of alternative mooring systems for floating wind turbines in shallow water with emphasis on ultimate limit state design. Ocean Engineering. vol. 219.
- (2020) Extreme responses and associated uncertainties for a long end-anchored floating bridge. Engineering structures. vol. 219.
- (2020) Design, Modelling and Analysis of a Large Floating Dock for Spar Floating Wind Turbine Installation. Marine Structures. vol. 72.
- (2020) Recent Advances in Integrated Response Analsysis of Floating Wind Turbines in a Reliability Perspective. Journal of Offshore Mechanics and Arctic Engineering. vol. 142 (5).
- (2020) Active Single-Blade Installation Using Tugger Line Tension Control and Optimal Control Allocation. International Journal of Offshore and Polar Engineering. vol. 30 (2).
- (2020) Multi-step-ahead forecasting of wave conditions based on a physics-based machine learning (PBML) model for marine operations. Journal of Marine Science and Engineering. vol. 8 (12).
- (2019) Numerical Modeling and Dynamic Analysis of a Floating Bridge Subjected to Wind, Wave, and Current Loads. Journal of Offshore Mechanics and Arctic Engineering. vol. 141 (1).
- (2019) Loading and blade deflection of a tidal turbine in waves. Journal of Offshore Mechanics and Arctic Engineering. vol. 141 (4).
- (2019) On the sensitivity and uncertainty of wave energy conversion with an artificial neural-network-based controller. Ocean Engineering. vol. 183.
- (2019) Response-Based Assessment of Operational Limits for Mating Blades on Monopile-Type Offshore Wind Turbines. Energies. vol. 12 (10).
- (2019) A comprehensive numerical investigation of the impact behaviour of an offshore wind turbine blade due to impact loads during installation. Ocean Engineering. vol. 172 (C).
- (2019) Prediction of short-term wind and wave conditions for marine operations using a multi-step-ahead decomposition-ANFIS model and quantification of its uncertainty. Ocean Engineering. vol. 188.
- (2019) Effect of wave nonlinearity on fatigue damage and extreme responses of a semi-submersible floating wind turbine. Applied Ocean Research. vol. 91.
- (2019) Numerical study on the feasibility of offshore single blade installation by floating crane vessels. Marine Structures. vol. 64.
- (2018) Wave load effect analysis of a floating bridge in a fjord considering inhomogeneous wave conditions. Engineering structures. vol. 163.
- (2018) Condition monitoring of spar‐type floating wind turbine drivetrain using statistical fault diagnosis. Wind Energy. vol. 21 (7).
- (2018) Dynamic response analysis of a catamaran installation vessel during the positioning of a wind turbine assembly onto a spar foundation. Marine Structures. vol. 61.
- (2018) An integrated dynamic analysis method for simulating installation of single blades for wind turbines. Ocean Engineering. vol. 152.
- (2017) A fully coupled method for numerical modeling and dynamic analysis of floating vertical axis wind turbines. Renewable Energy. vol. 107.
- (2017) Diagnostic monitoring of drivetrain in a 5 MW spar-type floating wind turbine using Hilbert spectral analysis. Energy Procedia. vol. 137.
- (2017) Modified environmental contour method to determine the long-term extreme responses of a semi-submersible wind turbine. Ocean Engineering. vol. 142.
- (2017) Experimental validation of a time-domain approach for determining sectional loads in a floating wind turbine hull subjected to moderate waves. Energy Procedia. vol. 137.
- (2017) Development and verification of a time-domain approach for determining forces and moments in structural components of floaters with an application to floating wind turbines. Marine Structures. vol. 51.
- (2017) Numerical assessment of wind turbine blade damage due to contact/impact with tower during installation. IOP Conference Series: Materials Science and Engineering. vol. 276.
- (2017) A combined wind and wave energy-converter concept in survival mode: Numerical and experimental study in regular waves with a focus on water entry and exit. Applied Ocean Research. vol. 63.
- (2016) Response analysis and comparison of a spar-type floating offshore wind turbine and an onshore wind turbine under blade pitch controller faults. Wind Energy. vol. 19 (1).
- (2016) Comparative Numerical and Experimental Study of two Combined Wind and Wave Energy Concepts. Journal of Ocean Engineering and Science. vol. 1 (1).
- (2016) Statistical fault diagnosis of wind turbine drivetrain applied to a 5MW floating wind turbine. Journal of Physics: Conference Series (JPCS). vol. 753.
- (2016) Methodology for assessment of the operational limits and operability of marine operations. Ocean Engineering. vol. 125.
- (2016) Modified environmental contour method for predicting long-term extreme responses of bottom-fixed offshore wind turbines. Marine Structures. vol. 48.
- (2016) Experimental and numerical study of the response of the offshore combined wind/wave energy concept SFC in extreme environmental conditions. Marine Structures. vol. 50.
- (2016) Experimental study of the functionality of a semisubmersible wind turbine combined with flap-type Wave Energy Converters. Renewable Energy. vol. 93.
- (2016) Development of a 5 MW reference gearbox for offshore wind turbines. Wind Energy. vol. 19 (6).
- (2016) Numerical study of ice-induced loads and responses of a monopile-type offshore wind turbine in parked and operating conditions. Cold Regions Science and Technology. vol. 123.
- (2016) Comparative experimental study of the survivability of a combined wind and wave energy converter in two testing facilities. Ocean Engineering. vol. 111.
- (2015) A comparative study of shutdown procedures on the dynamic responses of wind turbines. Journal of Offshore Mechanics and Arctic Engineering. vol. 137 (1).
- (2015) Joint Distribution of Environmental Condition at Five European Offshore Sites for Design of Combined Wind and Wave Energy Devices. Journal of Offshore Mechanics and Arctic Engineering. vol. 137 (3).
- (2015) Stochastic dynamic load effect and fatigue damage analysis of drivetrains in land-based and TLP, spar and semi-submersible floating wind turbines. Marine Structures. vol. 42.
- (2014) Analysis of lifting operation of a monopile for an offshore wind turbine considering vessel shielding effects. Marine Structures. vol. 39.
- (2014) On long-term fatigue damage and reliability analysis of gears under wind loads in offshore wind turbine drivetrains. International Journal of Fatigue. vol. 61.
- (2013) Application of the Contour Line Method for Estimating Extreme Responses in the Mooring Lines of a Two-Body Floating Wave Energy Converter. Journal of Offshore Mechanics and Arctic Engineering. vol. 135 (3).
- (2013) Analysis of a Two-Body Floating Wave Energy Converter with Particular Focus on the Effects of Power Take-Off and Mooring Systems on Energy Capture. Journal of Offshore Mechanics and Arctic Engineering. vol. 135 (3).
- (2012) Fatigue Reliability Analysis of the Jacket Support Structure for Offshore Wind Turbine Considering the Effect of Corrosion and Inspection. Reliability Engineering & System Safety. vol. 106.
- (2011) Long-term Fatigue Analysis of Multi-Planar Tubular Joints for Jacket-type Offshore Wind Turbine in Time Domain. Engineering structures. vol. 33 (6).
- (2008) Stochastic Response Analysis of Mooring Systems with Emphasis on Frequency-domain Analysis of Fatigue due to Wide-band Response Processes. 2008. ISBN 9788247159835. Doktoravhandlinger ved NTNU (2008:11).