Dan Sui | Universitetet i Stavanger

Kontakt

Telefon: 51831769

E-post: dan.sui@uis.no

Rom: KE E-301A

Organisasjonsenhet

Det teknisk-naturvitenskapelige fakultet

Institutt for energi- og petroleumsteknologi

Kort om meg

My research interests include drilling automation, digitalization, AI, machine learning, data processing and analytics, modeling, optimization and simulation, control system design (model predictive control, PID, moving horizon estimation, Kalman filter), advanced drilling technologies, drilling events detection, geothermal drilling and energy etc. I involve in many research projects within AI, digitalization and digital twin development.

Publikasjoner

Tilbake

Vitenskapelige publikasjoner
- Saavedra Jerez, Luis Alberto; Cayeux, Eric; Sui, Dan
  
  (2024)
  Facilitating Directional Drilling Work to Reach the Target Entry by Calculating a Safe Operating Envelope. I: IADC/SPE International Drilling Conference and Exhibition: March 5–7, 2024, Galveston, Texas, USA.
  Society of Petroleum Engineers.
  
  ISBN 978-1-959025-10-8.
  
  DOI: 10.2118/217707-MS
- Saavedra Jerez, Luis Alberto; Cayeux, Eric; Sui, Dan
  
  (2024)
  Assisting Directional Drilling by Calculating a Safe Operating Envelope.
  SPE Journal.
  
  ISSN 1086-055X.
  
  s.1-17.
  
  DOI: 10.2118/217707-PA
- Ma, Yucong; Xing, Yihan; Sui, Dan; Ong, Muk Chen; Hemmingsen, Tor
  
  (2023)
  Two-Dimensional Planar Modeling of the Depth Control of a Subsea Shuttle Tanker.
  Journal of Offshore Mechanics and Arctic Engineering.
  
  ISSN 0892-7219.
  
  Volum 145.
  
  Hefte 4.
  
  DOI: 10.1115/1.4056418
- Sui, Dan; Sahebi, Hamed
  
  (2023)
  Trend and dynamic analysis on temporal drilling data and their data-driven models.
  Geoenergy Science and Engineering.
  
  ISSN 2949-8929.
  
  Volum 223.
  
  DOI: 10.1016/j.geoen.2023.211530
- Cao, Jie; Tunkiel, Andrzej Tadeusz; Arild, Øystein; Sui, Dan
  
  (2023)
  Quantitative Evaluation of Imputation Methods Using Bounds Estimation of the Coefficient of Determination for Data-Driven Models with an Application to Drilling Logs.
  SPE Journal.
  
  ISSN 1086-055X.
  
  Volum 28.
  
  Hefte 4.
  
  s.1895-1911.
  
  DOI: 10.2118/214323-PA
- Tariq, Sofia; Sui, Dan
  
  (2023)
  Sensitivity Analysis and Feature Selection for Drilling-Oriented Models.
  Journal of energy resources technology.
  
  ISSN 0195-0738.
  
  Volum 145.
  
  Hefte 12.
  
  DOI: 10.1115/1.4062382
- Usama, Muhammad; Cao, Jie; Gravdal, Jan Einar; Sui, Dan
  
  (2023)
  Applied Reinforcement Learning Method for Pressure Control in Managed Pressure Drilling.
  Chinese Control Conference (CCC).
  
  ISSN 1934-1768.
  
  Volum 42.
  
  Hefte 24-26 July.
  
  s.1-6.
  
  DOI: 10.23919/CCC58697.2023.10239724
- Blesseth Ochije, Uchenna; Gravdal, Jan Einar; Sui, Dan
  
  (2023)
  Automated Real-Time Rate of Penetration Trend and Dynamic Analysis in Drilling Operations.
  Chinese Control Conference (CCC).
  
  ISSN 1934-1768.
  
  Volum 42.
  
  Hefte 24-26 July.
  
  s.7030-7035.
  
  DOI: 10.23919/CCC58697.2023.10240948
- Cao, Jie; Sui, Dan
  
  (2022)
  Well Path Design and Optimization Using Composite Cubic Bezier Curves.
  SPE Journal.
  
  ISSN 1086-055X.
  
  Volum 27.
  
  Hefte 6.
  
  s.3254-3270.
  
  DOI: 10.2118/209830-PA
- Cao, Jie; Wiktorski, Ekaterina; Sui, Dan
  
  (2022)
  Well Trajectory Optimization with an Emphasis on Anti-Collision Design.
  Journal of Offshore Mechanics and Arctic Engineering.
  
  ISSN 0892-7219.
  
  Volum 144.
  
  Hefte 4.
  
  DOI: 10.1115/1.4053654
- Saavedra Jerez, Luis Alberto; Haque, MD Fazlul; Magalhaes, Melissa; Chevuri, Rishyank; Sui, Dan; Florence, Fred
  
  (2022)
  Autonomous directional drilling using the RSS simulator for the drillbotics 2020-2021 virtual competition. I: IADC/SPE International Drilling Conference and Exhibition March 8–10, 2022 .
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-842-7.
  
  DOI: 10.2118/208774-MS
- Ma, Yucong; Xing, Yihan; Sui, Dan
  
  (2022)
  Trajectory Envelope of a Subsea Shuttle Tanker Hovering in Stochastic Ocean Current - Model Development and Tuning.
  Journal of Offshore Mechanics and Arctic Engineering.
  
  ISSN 0892-7219.
  
  Volum 145.
  
  Hefte 3.
  
  DOI: 10.1115/1.4055282
- Ma, Yucong; Xing, Yihan; Simplicio Da Silva, Marina; Sui, Dan
  
  (2022)
  Modelling of a Subsea Shuttle Tanker Hovering in Ocean Currents. I: ASME 2022 41st International Conference on Ocean, Offshore and Arctic Engineering Volume 5B: Ocean Engineering; Honoring Symposium for Professor Günther F. Clauss on Hydrodynamics and Ocean Engineering.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8590-1.
  
  DOI: 10.1115/OMAE2022-78146
- Saavedra Jerez, Luis Alberto; Sui, Dan
  
  (2022)
  Modeling and Algorithm Development for Well Trajectory Plan and Real-Time Trajectory Control. I: Proceedings of ASME 2022 41st International Conference on Ocean, Offshore & Arctic Engineering Volume 10 : Petroleum technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8595-6.
  
  DOI: 10.1115/OMAE2022-78451
- Sahebi, Hamed; Wiktorski, Ekaterina; Sui, Dan
  
  (2022)
  Design, Optimization, and Visualization of Wellbore Trajectory in 3D. I: SPE Norway Subsurface Conference 2022.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-857-1.
  
  DOI: 10.2118/209530-MS
- Fernandez Berrocal, Miguel; Cao, Jie; Sui, Dan
  
  (2022)
  Evaluation and Interpretation on Data Driven ROP Models From Engineering Perspectives . I: Proceedings of ASME 2022 41st International Conference on Ocean, Offshore & Arctic Engineering Volume 10 : Petroleum technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8595-6.
  
  DOI: 10.1115/OMAE2022-78752
- Cao, Jie; Chowdhury, Samiul Ehsan; Wiktorski, Tomasz; Sui, Dan
  
  (2022)
  Well path design using Q-learning algorithms and Bezier curves with obstacles avoidance. I: Proceedings of ASME 2022 41st International Conference on Ocean, Offshore & Arctic Engineering Volume 10 : Petroleum technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8595-6.
  
  DOI: 10.1115/OMAE2022-78427
- Cao, Jie; Ren, Hui; Sui, Dan
  
  (2022)
  Global optimization workflow for offshore drilling rate of penetration with dynamic drilling log data. I: Proceedings of ASME 2022 41st International Conference on Ocean, Offshore & Arctic Engineering Volume 10 : Petroleum technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8595-6.
  
  DOI: 10.1115/OMAE2022-79747
- Andrade, Caetano; Saavedra Jerez, Luis Alberto; Tunkiel, Andrzej Tadeusz; Sui, Dan
  
  (2021)
  Rotary steerable systems: mathematical modeling and their case study.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  Volum 11.
  
  s.2743-2761.
  
  DOI: 10.1007/s13202-021-01182-6
- Løken, Erik Andreas; Løkkevik, Jens; Sui, Dan
  
  (2021)
  Testing Machine Learning Algorithms for Drilling Incidents Detection on a Pilot Small-Scale Drilling Rig.
  Journal of energy resources technology.
  
  ISSN 0195-0738.
  
  Volum 143.
  
  Hefte 12.
  
  DOI: 10.1115/1.4052284
- Madeira, Rafael; Sui, Dan
  
  (2021)
  Study on separation factor models for well anti-collision analysis.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  Volum 11.
  
  s.3463-3477.
  
  DOI: 10.1007/s13202-021-01235-w
- Gravdal, Jan Einar; Sui, Dan; Nagy, Attila; Saadallah, Nejm; Ewald, Robert
  
  (2021)
  A hybrid test environment for verification of drilling automation systems. I: IADC/SPE Managed Pressure Drilling & Underbalanced Operations Conference & Exhibition, Virtual, September 2021.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-742-0.
  
  DOI: 10.2118/204064-MS
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2021)
  Automated iterative gap filling method for drilling logs and other data series. I: ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering Volume 10: Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8520-8.
  
  DOI: 10.1115/OMAE2021-61927
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2021)
  Impact of data pre-processing techniques on recurrent neural network performance in context of real-time drilling logs in an automated prediction framework.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  DOI: 10.1016/j.petrol.2021.109760
- Ma, Yucong; Sui, Dan; Xing, Yihan; Ong, Muk Chen; Hemmingsen, Tor Henning
  
  (2021)
  Depth control modelling and analysis of a subsea shuttle tanker . I: ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering Volume 5: Ocean Space Utilization.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8515-4.
  
  DOI: 10.1115/OMAE2021-61827
- Encinas, Mauro; Tunkiel, Andrzej Tadeusz; Sui, Dan
  
  (2021)
  Downhole data correction for data-driven rate of penetration prediction modeling.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  DOI: 10.1016/j.petrol.2021.109904
- Wiktorski, Ekaterina; Sui, Dan
  
  (2021)
  Algorithms and models for smart well planning with emphasis on trajectory optimization. I: ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering Volume 10: Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8520-8.
  
  DOI: 10.1115/OMAE2021-62731
- Wiktorski, Ekaterina; Sui, Dan
  
  (2021)
  Investigation of model configuration parameters for stick-slip modeling. I: ASME 2021 40th International Conference on Ocean, Offshore and Arctic Engineering Volume 10: Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8520-8.
  
  DOI: 10.1115/OMAE2021-62744
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2020)
  Data-driven sensitivity analysis of complex machine learning models: A case study of directional drilling.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  Volum 195.
  
  DOI: 10.1016/j.petrol.2020.107630
- Sui, Dan; Vidaur, Juan Carlos Martinez
  
  (2020)
  Automated Characterization of Non-Newtonian Fluids Using Laboratory Setup.
  Applied Rheology.
  
  ISSN 1430-6395.
  
  Volum 30.
  
  Hefte 1.
  
  s.39-53.
  
  DOI: 10.1515/arh-2020-0101
- Løken, Erik Andreas; Løkkevik, Jens; Sui, Dan
  
  (2020)
  Automated drilling algorithms implementation on a laboratory drilling rig.
  MIC Journal: Modeling, Identification and Control.
  
  ISSN 0332-7353.
  
  Volum 41.
  
  Hefte 1.
  
  s.1-11.
  
  DOI: 10.4173/mic.2020.1.1
- Løken, Erik Andreas; Løkkevik, Jens; Sui, Dan
  
  (2020)
  Data-driven Approaches Tests on A Laboratory Drilling System.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  DOI: 10.1007/s13202-020-00870-z
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2020)
  Reference Dataset for Rate of Penetration Benchmarking.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  DOI: 10.1016/j.petrol.2020.108069
- Hemba Geekiyanage, Suranga Chaminda; Tunkiel, Andrzej Tadeusz; Sui, Dan
  
  (2020)
  Drilling data quality improvement and information extraction with case studies.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  DOI: 10.1007/s13202-020-01024-x
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2020)
  Training-while-drilling approach to inclination prediction in directional drilling utilizing recurrent neural networks.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  Volum 196.
  
  DOI: 10.1016/j.petrol.2020.108128
- Gravdal, Jan Einar; Ewald, Robert; Saadallah, Nejm; Moi, Sonja; Sui, Dan; Shor, Roman
  
  (2020)
  A New Approach to Development and Validation of Artificial Intelligence Systems for Drilling.
  IEEE Conference on Industrial Electronics and Applications.
  
  ISSN 2158-2297.
  
  s.302-307.
  
  DOI: 10.1109/ICIEA48937.2020.9248210
- Tunkiel, Andrzej Tadeusz; Wiktorski, Tomasz; Sui, Dan
  
  (2020)
  Drilling Dataset Exploration, Processing and Interpretation Using Volve Field Data. I: ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering - Volume 11: Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8443-0.
  
  DOI: 10.1115/OMAE2020-18151
- Tunkiel, Andrzej Tadeusz; Wiktorski, Tomasz; Sui, Dan
  
  (2020)
  Continuous Drilling Sensor Data Reconstruction and Prediction via Recurrent Neural Networks. I: ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering - Volume 1: Offshore Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8431-7.
  
  DOI: 10.1115/OMAE2020-18154
- Wiktorski, Ekaterina; Sui, Dan
  
  (2020)
  Investigation of Stick-Slip Severity in a Coupled Axial-Torsional Drillstring Dynamics Using a Two DOF Finite Element Mode. I: ASME 2020 39th International Conference on Ocean, Offshore and Arctic Engineering - Volume 11: Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-8443-0.
  
  DOI: 10.1115/OMAE2020-19320
- Wiktorski, Ekaterina; Cobbah, Catherine; Sui, Dan; Khalifeh, Mahmoud
  
  (2019)
  Experimental study of temperature effects on wellbore material properties to enhance temperature profile modeling for production wells .
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  Volum 176.
  
  s.689-701.
  
  DOI: 10.1016/j.petrol.2019.01.102
- Saadallah, Nejm; Gravdal, Jan Einar; Ewald, Robert; Moi, Sonja; Daireaux, Benoit; Ambrus, Adrian; Sivertsen, Stian; Hellang, Kristian; Shor, Roman J.; Sui, Dan; Sandor, Stefan; Chojnacki, Marek; Odgaard, Jacob
  
  (2019)
  OpenLab: Design and Applications of a Modern Drilling Digitalization Infrastructure.
  Society of Petroleum Engineering.
  
  DOI: 10.2118/195629-MS
- Khadisov, Magomed Adan; Hagen, Håkon Petersen; Jakobsen, Andreas Sandvi; Sui, Dan
  
  (2019)
  Developments and experimental tests on a laboratory-scale drilling automation system.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  s.1-17.
  
  DOI: 10.1007/s13202-019-00767-6
- Hemba Geekiyanage, Suranga Chaminda; Løken, Erik Andreas; Sui, Dan
  
  (2019)
  Architectures and algorithms of an autonomous small-scale drilling agent.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  Volum 188.
  
  s.1-17.
  
  DOI: 10.1016/j.petrol.2019.106834
- Wiktorski, Ekaterina; Sui, Dan; Khalifeh, Mahmoud; Khatibi, Milad
  
  (2019)
  Investigation of the Combined Effects of Temperature and Large-Scale Tortuosity on Friction-Factor Profile in Straight Inclined Sections.
  SPE Journal.
  
  ISSN 1086-055X.
  
  DOI: 10.2118/198897-PA
- Hemba Geekiyanage, Suranga Chaminda; Løken, Erik Andreas; Sui, Dan; Wiktorski, Tomasz
  
  (2019)
  Architectures and algorithms for a smart drilling robot. I: ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering (OMAE2019): Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5887-5.
  
  DOI: 10.1115/OMAE2019-95486
- Hemba Geekiyanage, Suranga Chaminda; Ambrus, Adrian; Sui, Dan
  
  (2019)
  Feature selection for kick detection with machine learning using laboratory data. I: ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering (OMAE2019): Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5887-5.
  
  DOI: 10.1115/OMAE2019-95496
- Wiktorski, Ekaterina; Hemba Geekiyanage, Suranga Chaminda; Løken, Erik Andreas; Sui, Dan
  
  (2019)
  Comparative Study of Surface and Downhole Drillstring Vibrations Measurements on a Laboratory-Scale Drilling Rig. I: SPE Norway One Day.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-670-6.
  
  DOI: 10.2118/195610-MS
- Wiktorski, Ekaterina; Khatibi, Milad; Hemba Geekiyanage, Suranga Chaminda; Sui, Dan; Time, Rune Wiggo
  
  (2019)
  Experimental Study of Drillstring Dynamics Using a High-Speed Camera As a Non-Invasive Motion Sensor. I: ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering (OMAE2019): Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5887-5.
  
  DOI: 10.1115/OMAE2019-95217
- Løken, Erik Andreas; Hemba Geekiyanage, Suranga Chaminda; Sui, Dan; Ewald, Robert
  
  (2018)
  Autonomous Laboratory-Scale Drilling Rig for Testing and Control of Drilling Systems.
  Oil, Gas.
  
  ISSN 0342-5622.
  
  Hefte 1.
  
  s.38-39.
  
  DOI: 10.19225/180310
- Løken, Erik Andreas; Trulsen, Alexander; Holsaeter, Andrew Martin; Wiktorski, Ekaterina; Sui, Dan; Ewald, Robert
  
  (2018)
  Design Principles Behind the Construction of an Autonomous Laboratory-Scale Drilling Rig.
  IFAC-PapersOnLine.
  
  ISSN 2405-8963.
  
  Volum 51.
  
  Hefte 8.
  
  s.62-69.
  
  DOI: 10.1016/j.ifacol.2018.06.356
- de Sousa Gomes, Dalila; Nilsen, Marius Staahl; Frøyen, Johnny; Bjørkevoll, Knut Steinar; Lage, Antonio C V M; Fjelde, Kjell Kåre; Sui, Dan
  
  (2018)
  A Transient Flow Model for Investigating Parameters Affecting Kick Behaviour in OBM for HPHT Wells and Backpressure MPD Systems. I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77547
- Udegbunam, John Emeka; Fjelde, Kjell Kåre; Sui, Dan
  
  (2018)
  Numerical Integration of the AUSMV Scheme with a Dynamic Wellbore Temperature Model . I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77493
- Sui, Dan; Horpestad, Thomas; Wiktorski, Ekaterina
  
  (2018)
  Comprehensive modeling for temperature distributions of production andgeothermal wells.
  Journal of Petroleum Science and Engineering.
  
  ISSN 0920-4105.
  
  Volum 167.
  
  s.426-446.
  
  DOI: 10.1016/j.petrol.2018.03.060
- Sui, Dan; Langåker, Vebjørn Haraldstad
  
  (2018)
  Downhole Temperature Modeling for Non-Newtonian Fluids in ERD Wells.
  MIC Journal: Modeling, Identification and Control.
  
  ISSN 0332-7353.
  
  Volum 39.
  
  Hefte 2.
  
  s.131-149.
  
  DOI: 10.4173/mic.2018.2.7
- Sui, Dan; Wiktorski, Ekaterina; Røksland, Marius; Basmoen, Tommy A.
  
  (2018)
  Review and investigations on geothermal energy extraction from abandoned petroleum wells.
  Journal of Petroleum Exploration and Production Technology.
  
  ISSN 2190-0558.
  
  s.1-13.
  
  DOI: 10.1007/s13202-018-0535-3
- Wiktorski, Ekaterina; Khatibi, Milad; Sui, Dan; Time, Rune Wiggo
  
  (2018)
  Study of Frictional Forces Between Rotating Pipes and Wellbore in Horizontal Wells: Experimental and Modelling. I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77105
- Hemba Geekiyanage, Suranga Chaminda; Sui, Dan; Aadnøy, Bernt Sigve
  
  (2018)
  Drilling data quality management: Case study with a laboratory scale drilling rig. I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77510
- Leulseged, Amare; Nepal, Sima Alise; Sui, Dan; Hemba Geekiyanage, Suranga Chaminda
  
  (2018)
  Kick Management Study on Automated Well Control for Managed Pressure Drilling in Long Wells. I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77800
- Ewald, Robert; Gravdal, Jan Einar; Sui, Dan; Shor, Roman
  
  (2018)
  Web Enabled High Fidelity Drilling Computer Model with User-Friendly Interface for Education, Research and Innovation.
  Linköping Electronic Conference Proceedings.
  
  ISSN 1650-3686.
  
  Hefte 153.
  
  s.162-168.
  
  DOI: 10.3384/ecp18153162
- Wiktorski, Ekaterina; Sui, Dan; Fjelde, Kjell Kåre; Langåker, Vebjørn
  
  (2018)
  Dynamic Cuttings Slip Velocity Evaluation in Non-Newtonian Fluids Using a Temperature Dependent Transient Drift-Flux Model for Directional Wells. I: ASME 2018 37th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology.
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5129-6.
  
  DOI: 10.1115/OMAE2018-77386
- Sui, Dan; Sukhoboka, Olha; Aadnøy, Bernt Sigve
  
  (2017)
  Improvement of Wired Drill Pipe Data Quality via Data Validation and Reconciliation.
  International Journal of Automation and Computing.
  
  ISSN 1476-8186.
  
  s.1-12.
  
  DOI: 10.1007/s11633-017-1068-9
- de Sousa Gomes, Dalila; Bjørkevoll, Knut Steinar; Frøyen, Johnny; Fjelde, Kjell Kåre; Sui, Dan; Udegbunam, John Emeka; Moeinikia, Fatemeh
  
  (2017)
  Probabilistic Flow Modelling Approach for Kick Tolerance Calculations. I: ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology, Trondheim, Norway, June 25–30, 2017 .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5776-2.
  
  DOI: 10.1115/OMAE2017-61391
- Wiktorski, Ekaterina; Tveiterå, Martin; Sui, Dan; Aadnøy, Bernt Sigve
  
  (2017)
  Temperature Dependent Torque and Drag for 3-D Wells: Model Description and Field Case Study. I: ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology, Trondheim, Norway, June 25–30, 2017 .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5776-2.
  
  DOI: 10.1115/OMAE2017-61230
- Udegbunam, John Emeka; Sui, Dan; Moeinikia, Fatemeh; Lage, Antonio C V M; Fjelde, Kjell Kåre; Arild, Øystein; Rabenjafimanantsoa, Herimonja Andrianifaliana; Nygaard, Olav Gerhard Haukenes
  
  (2017)
  A Transient Flow Model for Predicting Pressure Buildup in Closed Annuli. I: ASME 2017 36th International Conference on Ocean, Offshore and Arctic Engineering - Volume 8: Polar and Arctic Sciences and Technology; Petroleum Technology, Trondheim, Norway, June 25–30, 2017 .
  The American Society of Mechanical Engineers (ASME).
  
  ISBN 978-0-7918-5776-2.
  
  DOI: 10.1115/OMAE2017-61209
- Cayeux, Eric; Sui, Dan; Akisanmi, Olaleke Anthony; Alani, Omar Salem
  
  (2017)
  Challenges in the Automation of a Laboratory-Scale Drilling Rig and Comparison with the Requirements for Full Scale Drilling Automation. I: SPE Bergen One Day Seminar, 2017.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-549-5.
  
  DOI: 10.2118/185898-MS
- Røksland, Marius; Basmoen, Tommy A.; Sui, Dan
  
  (2017)
  Geothermal energy extraction from abandoned wells.
  Energy Procedia.
  
  ISSN 1876-6102.
  
  Volum 105.
  
  s.244-249.
  
  DOI: 10.1016/j.egypro.2017.03.309
- Sui, Dan; Langåker, Vebjørn; Yu, Zhixin
  
  (2017)
  Investigation of Thermophysical Properties of Nanofluids for Application in Geothermal Energy.
  Energy Procedia.
  
  ISSN 1876-6102.
  
  Volum 105.
  
  s.5055-5060.
  
  DOI: 10.1016/j.egypro.2017.03.1021
- Sui, Dan; Aadnøy, Bernt Sigve
  
  (2016)
  Rate of Penetration Optimization using Moving Horizon Estimation.
  MIC Journal: Modeling, Identification and Control.
  
  ISSN 0332-7353.
  
  Volum 37.
  
  Hefte 3.
  
  s.149-158.
  
  DOI: 10.4173/mic.2016.3.1
- Zhao, Kairui; Sui, Dan
  
  (2015)
  Drilling data quality control via wired drill pipe technology.
  Chinese Control Conference (CCC).
  
  ISSN 1934-1768.
  
  Volum 2015-September.
  
  s.7883-7888.
  
  DOI: 10.1109/ChiCC.2015.7260892
- Sui, Dan; Nygaard, Olav Gerhard Haukenes
  
  (2015)
  Automated dual gradient drilling and its parametric analysis during connection.
  IFAC-PapersOnLine.
  
  ISSN 2405-8963.
  
  Volum 48.
  
  Hefte 6.
  
  s.183-188.
  
  DOI: 10.1016/j.ifacol.2015.08.029
- Nybø, Roar; Sui, Dan
  
  (2014)
  SPE 167864 - Closing the Integration Gap for the Next Generation of Drilling Decision Support Systems. I: SPE Intelligent Energy Conference and Exhibition, Nederland, 1-3 April 2014 - Conference Proceedings.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-306-4.
  
  DOI: 10.2118/167864-MS
- Sui, Dan; Johansen, Tor Arne
  
  (2014)
  Linear constrained moving horizon estimator with pre-estimating observer.
  Systems & control letters (Print).
  
  ISSN 0167-6911.
  
  Volum 67.
  
  s.40-45.
  
  DOI: 10.1016/j.sysconle.2014.02.003
- Johansen, Tor Arne; Sui, Dan; Nybø, Roar
  
  (2013)
  Regularized Nonlinear Moving-Horizon Observer With Robustness to Delayed and Lost Data.
  IEEE Transactions on Control Systems Technology.
  
  ISSN 1063-6536.
  
  Volum 21.
  
  Hefte 6.
  
  s.2114-2128.
  
  DOI: 10.1109/TCST.2012.2228652
- Sui, Dan; Nybø, Roar; Azizi, Vahid
  
  (2013)
  Real-time Optimization of Rate of Penetration during Drilling Operation.
  IEEE International Conference on Control and Automation.
  
  ISSN 1948-3449.
  
  s.357-362.
  
  DOI: 10.1109/ICCA.2013.6564893
- Gjerstad, Kristian; Sui, Dan; Bjørkevoll, Knut Steinar; Time, Rune Wiggo
  
  (2013)
  Automatic Prediction of Downhole Pressure Surges in Tripping Operations. I: International Petroleum Technology Conference, 26-28 March, Beijing, China.
  Society of Petroleum Engineers.
  
  ISBN 978-1-61399-218-0.
  
  DOI: 10.2523/16974-MS
- Feng, Le; Gutvik, Christian Ragnar; Johansen, Tor Arne; Sui, Dan; Brubakk, Alf O
  
  (2012)
  Approximate Explicit Nonlinear Receding Horizon Control for Decompression of Divers.
  IEEE Transactions on Control Systems Technology.
  
  ISSN 1063-6536.
  
  Volum 20.
  
  Hefte 5.
  
  s.1275-1284.
  
  DOI: 10.1109/TCST.2011.2162516
- Sui, Dan; Johansen, Tor Arne
  
  (2012)
  On the Exponential Stability of Moving Horizon Observer for Globally N-Detectable Nonlinear Systems.
  Asian journal of control.
  
  ISSN 1561-8625.
  
  Volum 14.
  
  Hefte 6.
  
  s.1649-1654.
  
  DOI: 10.1002/asjc.475
- Sui, Dan; Nybø, Roar; Hovland, Svein; Johansen, Tor Arne
  
  (2012)
  A Moving Horizon Observer for Estimation of Bottomhole Pressure during Drilling.
  Elsevier IFAC Publications / IFAC Proceedings series.
  
  ISSN 1474-6670.
  
  s.145-150.
  
  DOI: 10.3182/20120531-2-NO-4020.00024
- Sui, Dan; Johansen, Tor Arne
  
  (2011)
  Moving horizon observer with regularisation for detectable systems without persistence of excitation.
  International Journal of Control.
  
  ISSN 0020-7179.
  
  Volum 84.
  
  Hefte 6.
  
  s.1041-1054.
  
  DOI: 10.1080/00207179.2011.589081
- Sui, Dan; Johansen, Tor Arne
  
  (2011)
  Exponential Stability of Regularized Moving Horizon Observer for N-Detectable Nonlinear Systems. I: Proceedings 2011 IEEE International Conference on Control and Automation, Santiago, Chile.
  IEEE Press.
  
  ISBN 978-1-4577-1474-0.
  
  s.806-811.
  
  DOI: 10.1109/icca.2011.6137886
- Sui, Dan; Johansen, Tor Arne
  
  (2011)
  
  Regularized Nonlinear Moving Horizon Observer – Theory and application to automotive friction estimation. I: Preprints of the NIL workshop on Selected Topics on Constrained and Nonlinear Control.
  
  ISBN 978-80-968627-2-6.
  
  s.3-20.
- Gola, Giulio; Nybø, Roar; Sui, Dan
  
  (2011)
  
  A grey-box approach for predicting the well bottom-hole pressure in pressure-controlled drilling operations. I: Proceedings of the 24th International Congress on Condition Monitoring and Diagnostics Engineering Management (COMADEM2011).
  
  COMADEM International.
  
  ISBN 0-9541307-2-3.
- Sui, Dan; Nybø, Roar; Gola, Giulio; Roverso, Davide; Hoffmann, Marinus I
  
  (2011)
  Ensemble methods for process monitoring in oil and gas industry operations.
  Journal of Natural Gas Science and Engineering.
  
  ISSN 1875-5100.
  
  Volum 3.
  
  Hefte 6.
  
  s.748-753.
  
  DOI: 10.1016/j.jngse.2011.05.004
- Sui, Dan; Feng, Le; Ong, C.J.; Hovd, Morten
  
  (2010)
  Robust explicit model predictive control for linear systems via interpolation techniques.
  International Journal of Robust and Nonlinear Control.
  
  ISSN 1049-8923.
  
  Volum 20.
  
  Hefte 10.
  
  s.1166-1175.
  
  DOI: 10.1002/rnc.1500
- Sui, Dan; Johansen, Tor Arne; Feng, Le
  
  (2010)
  Linear Moving Horizon Estimation With Pre-Estimating Observer.
  IEEE Transactions on Automatic Control.
  
  ISSN 0018-9286.
  
  Volum 55.
  
  Hefte 10.
  
  s.2363-2368.
  
  DOI: 10.1109/TAC.2010.2053060
- Sui, Dan; Johansen, Tor Arne
  
  (2010)
  
  Moving Horizon Estimation for Tire-Road Friction During Braking.
  
  Proceedings of the IEEE Conference on Control Applications.
  
  ISSN 1085-1992.
  
  s.1379-1384.
- Sui, Dan; Johansen, Tor Arne
  
  (2010)
  
  Regularized Nonlinear Moving Horizon Observer for Detectable Systems.
  
  Elsevier IFAC Publications / IFAC Proceedings series.
  
  ISSN 1474-6670.
- Le, Feng; Gutvik, Christian Ragnar; Johansen, Tor Arne; Sui, Dan
  
  (2009)
  
  Barrier Function Nonlinear Optimization for Optimal Decompression of Divers.
  
  Proceedings of the IEEE Conference on Decision & Control, including the Symposium on Adaptive Processes.
  
  ISSN 0191-2216.
- Sui, Dan; Le, Feng; Hovd, Morten; Ong, C.J.
  
  (2009)
  Decomposition principle in model predictive control for linear systems with bounded disturbances.
  Automatica.
  
  ISSN 0005-1098.
  
  Volum 45.
  
  Hefte 8.
  
  s.1917-1922.
  
  DOI: 10.1016/j.automatica.2009.04.012
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2009)
  Robust Explicit Moving Horizon Control and Estimation: A Batch Polymerization Case Study.
  MIC Journal: Modeling, Identification and Control.
  
  ISSN 0332-7353.
  
  Volum 30.
  
  Hefte 1.
  
  s.17-U27.
  
  DOI: 10.4173/mic.2009.1.2
- Sui, Dan; Ong, CJ; Feng, L
  
  (2009)
  A framework for multiple robust explicit MPC controllers for linear systems.
  International Journal of Control.
  
  ISSN 0020-7179.
  
  Volum 82.
  
  Hefte 8.
  
  s.1414-1422.
  
  DOI: 10.1080/00207170802400947
- Sui, Dan; Ong, CJ
  
  (2008)
  Constrained piecewise linear systems with disturbances: Controller design via convex invariant sets.
  International Journal of Robust and Nonlinear Control.
  
  ISSN 1049-8923.
  
  Volum 18.
  
  s.1327-1347.
  
  DOI: 10.1002/rnc.1279
- Sui, Dan; Le, Feng; Ong, CJ
  
  (2008)
  Interpolated robust time optimal controllers for linear systems.
  IET Control Theory & Applications.
  
  ISSN 1751-8644.
  
  Volum 2.
  
  s.219-227.
  
  DOI: 10.1049/iet-cta:20070001
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Algorithms for online implementations of explicit MPC solutions.
  
  Elsevier IFAC Publications / IFAC Proceedings series.
  
  ISSN 1474-6670.
  
  Volum 17.
  
  Hefte 1.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust output feedback MPC for linear systems via interpolation technique.
  
  Elsevier IFAC Publications / IFAC Proceedings series.
  
  ISSN 1474-6670.
  
  Volum 17.
  
  Hefte 1.
- Le, Feng; Sui, Dan; Hovd, Morten
  
  (2008)
  
  On further optimizing prediction dynamics for robust model predictive control.
  
  American Control Conference (ACC).
  
  ISSN 0743-1619.
  
  s.3572-3576.
- Sui, Dan; Ong, C.J.
  
  (2007)
  
  Interpolated Model Predictive Controller for Linear Systems with Bounded Disturbances.
  
  American Control Conference (ACC).
  
  ISSN 0743-1619.
  
  s.4458-4463.
- Sui, Dan; Ong, C.J.
  
  (2007)
  
  Computation of Polytopal Invariant Sets of PWL Systems with Bounded Disturbances.
  
  American Control Conference (ACC).
  
  ISSN 0743-1619.
  
  s.4655-4659.
Bøker og kapitler
Formidling
- Gravdal, Jan Einar; Sui, Dan; Nagy, Attila; Saadallah, Nejm; Ewald, Robert
  
  (2021)
  
  A Hybrid Test Environment for Verification of Drilling Automation Systems .
  
  SPE/IADC International Drilling Conference and Exhibition 2021;
  
  2021-03-08 - 2021-03-12.
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2020)
  
  OMAE2020-18151: Drilling Dataset Exploration, Processing and Interpretation Using Volve Field Data.
  
  OMAE 2020;
  
  2020-08-03 - 2020-08-07.
- Tunkiel, Andrzej Tadeusz; Sui, Dan; Wiktorski, Tomasz
  
  (2020)
  
  OMAE2020-18154: Continuous Drilling Sensor Data Reconstruction and Prediction via Recurrent Neural Networks.
  
  OMAE 2020;
  
  2020-08-03 - 2020-08-07.
- Hemba Geekiyanage, Suranga Chaminda; Løken, Erik Andreas; Sui, Dan; Wiktorski, Tomasz
  
  (2019)
  
  Architectures and algorithms for a smart drilling robot.
  
  Proceedings of the ASME 2019 38th International OMAE Conference;
  
  2019-06-09 - 2019-06-14.
- Hemba Geekiyanage, Suranga Chaminda; Ambrus, Adrian; Sui, Dan
  
  (2019)
  
  Feature selection for kick detection with machine learning using laboratory data.
  
  Proceedings of the ASME 2019 38th OMAE International Conference;
  
  2019-06-09 - 2019-06-14.
- Wiktorski, Ekaterina; Khatibi, Milad; Geekiyanage, Suranga C. H.; Sui, Dan; Time, Rune Wiggo
  
  (2019)
  
  Experimental Study of drillstring dynamics using a high-speed camera as a non-invasive motion sensor.
  
  ASME 2019 38th International Conference on Ocean, Offshore and Arctic Engineering;
  
  2019-06-09 - 2019-06-14.
- Wiktorski, Ekaterina; Geekiyanage, Suranga C. H.; Løken, Erik Andreas; Sui, Dan
  
  (2019)
  
  Comparative study of surface and downhole drillstring vibrations measurements on a laboratory-scale drilling rig.
  
  SPE Norway One Day Seminar in Bergen 2019;
  
  2019-05-14.
- Leulseged, Amare; Sui, Dan; Nepal, Sima A.; Geekivanage, Suranga C. H.
  
  (2018)
  
  Kick Management Study on Automated Well Control for Managed Pressure Drilling in Long Wells.
  
  37th International Conference on Ocean, Offshore & Arctic Engineering;
  
  2018-06-17 - 2018-06-22.
- Aadnøy, Bernt Sigve; Sui, Dan
  
  (2018)
  
  The importance of physicis in drill string modelling.
  
  Fourth International Colloquium on Nonlinear Dynamics and Control of Deep Drilling Systems;
  
  2018-05-14 - 2018-05-16.
- Ewald, Robert; Gravdal, Jan Einar; Shor, Roman; Sui, Dan
  
  (2018)
  
  Web-enabled high fidelity drilling computer model with user-friendly interface for education, research and innovation.
  
  the 59th International Conference of Scandinavian Simulation Society, SIMS 2018;
  
  2018-09-26 - 2018-09-28.
- Khatibi, Milad; Wiktorski, Ekaterina; Sui, Dan; Time, Rune Wiggo
  
  (2018)
  
  Experimental Study of Frictional Pressure Loss for Eccentric Drillpipe in Horizontal Wells.
  
  IADC/SPE Asia Pacific Drilling Technology Conference and Exhibition, 27-29 August;
  
  2018-08-27 - 2018-08-29.
- Hemba Geekiyanage, Suranga Chaminda; Løken, Erik Andreas; Wiktorski, Ekaterina; Sui, Dan
  
  (2018)
  
  Design of a Finite State Machine: Case Study on Algorithms & Architecture for a Smart Drilling Rig.
  
  Celle Drilling 2018;
  
  2018-09-11 - 2018-09-12.
- Wiktorski, Ekaterina; Kuznetsov, Artem; Sui, Dan
  
  (2017)
  
  ROP Optimization and Modeling in Directional Drilling Process.
  
  SPE One Day Seminar in Bergen;
  
  2017-04-05.
- Sui, Dan; Nybø, Roar; Azizi, Vahid
  
  (2013)
  
  Real-time Optimization of Rate of Penetration during Drilling Operation.
  
  2013 10th IEEE International Conference on Control and Automation (ICCA);
  
  2013-06-12 - 2013-06-14.
- Gjerstad, Kristian; Sui, Dan; Bjørkevoll, Knut Steinar; Time, Rune Wiggo
  
  (2013)
  
  Automatic Prediction of Downhole Pressure Surges in Tripping Operations.
  
  International Petroleum Technology Conference;
  
  2013-03-26 - 2013-03-28.
- Guulio, Gola; Nybø, Roar; Sui, Dan; Roverso, Davide
  
  (2012)
  
  SPE 150201 - Improving management and control of drilling operations with artificial intelligence.
  
  SPE Intelligent Energy International;
  
  2012-03-27 - 2012-03-29.
- Sui, Dan; Gulsrud, Thor Ole; Kristoffersen, Espen
  
  (2012)
  
  SPE 149906 - Advanced PreDrill Simulations for Safer and More Cost-effective Drilling.
  
  IADC/SPE Drilling Conference and Exhibition;
  
  2012-03-06 - 2012-03-08.
- Sui, Dan; Johansen, Tor Arne
  
  (2011)
  
  Exponential Stability of Regularized Moving Horizon Observer for N-Detectable Nonlinear Systems.
  
  IEEE International Conference on Control & Automation (ICCA’11);
  
  2011-12-19 - 2011-12-21.
- Sui, Dan; Johansen, Tor Arne
  
  (2010)
  
  Moving Horizon Estimation for Tire-Road Friction During Braking.
  
  IEEE Multi-conference of Systems and Control;
  
  2010-09-08 - 2010-09-10.
- Sui, Dan; Johansen, Tor Arne
  
  (2010)
  
  Regularized Nonlinear Moving Horizon Observer for Detectable Systems.
  
  IFAC NOLCOS;
  
  2010-09-01 - 2010-09-03.
- Le, Feng; Gutvik, Christian Ragnar; Johansen, Tor Arne; Sui, Dan
  
  (2009)
  
  Barrier Function Nonlinear Optimization for Optimal Decompression of Divers.
  
  IEEE Conference on Decision and Control;
  
  2009-12-16 - 2009-12-18.
- Le, Feng; Sui, Dan; Hovd, Morten
  
  (2008)
  
  On further optimizing prediction dynamics for robust model predictive control.
  
  ACC 2008;
  
  2008-06-11 - 2008-06-13.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust output feedback model predictive control for linear systems via moving horizon estimation.
  
  ACC 2008;
  
  2008-06-11 - 2008-06-13.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust explicit time optimal controllers for linear systems via decomposition principle.
  
  17th IFAC world congress;
  
  2008-07-06 - 2008-07-11.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust output feedback MPC for linear systems via interpolation technique.
  
  17th IFAC world congress;
  
  2008-07-06 - 2008-07-11.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Algorithms for online implementations of explicit MPC solutions.
  
  17th IFAC World Congress;
  
  2008-07-06 - 2008-07-11.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust explicit time optimal controllers for linear systems via decomposition principle.
  
  Elsevier IFAC Publications / IFAC Proceedings series.
  
  ISSN 1474-6670.
  
  s.10196-10200.
- Sui, Dan; Le, Feng; Hovd, Morten
  
  (2008)
  
  Robust output feedback model predictive control for linear systems via moving horizon estimation.
  
  American Control Conference (ACC).
  
  ISSN 0743-1619.
  
  s.453-458.
- Sui, Dan; Ong, C.J.
  
  (2007)
  
  Computation of Polytopal Invariant Sets of PWL Systems with Bounded Disturbances.
  
  American Control Conference;
  
  2007-07-11 - 2007-07-13.
- Sui, Dan; Ong, C.J.
  
  (2007)
  
  Interpolated Model Predictive Controller for Linear Systems with Bounded Disturbances.
  
  American Control Conference;
  
  2007-07-11 - 2007-07-13.
Kunstnerisk produksjon
Kommersialisering