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Hans Cozijn

Senior Project Manager

Autonomy & Decision Support | Performance at Sea

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Introduction

Experienced professional with a background in hydrodynamics and naval architecture MSc. More than two decades of experience in scale model tests and numerical simulations for floating offshore structures. Specialities include floater motions coupled mooring analysis dynamic positioning green water loading autonomous vessels scale model tests timedomain simulations.

Expertise areas
Publications
Magazine
Sustainable shortsea shipping gets a step closer through EU MOSES project

20 Dec 2023

MARIN is a partner in the EU-funded project MOSES (AutoMated Vessels and Supply Chain Optimisation for Sustainable Short SEa Shipping). In this ...
Paper
Control of a full port-to-port mission for a feeder vessel

5 Jun 2023

Autonomy is posed as a solution to decrease the amount of qualified personnel on a ship. It would be especiallyadvantageous for those tasks that are ...
Paper
Simulation of a feeder on a port-to-port mission

5 Jun 2023

The path to autonomous shipping is paved with ambitious plans and futuristic concepts. From a realistic perspective,the transition from man-operated ...
Magazine
mAUV further developed with addition of relative navigation capabilities

20 Apr 2023

MARIN has designed and built the modular Autonomous Underwater Vehicle (mAUV) for use in research projects in its model basins. The mAUV has a ...
Paper
Control design for a multi-regime 6-DOF underwater vehicle- development of MARIN’s modular AUV

16 Sep 2019

Reading time 5 minutes

MARIN is designing and building a modular autonomous underwater vehicle (mAUV). The vehicle will serve as a platform for research projects to be ...
Paper
Design of an Underwater Vehicle for use in Basin Experiments, Development of MARIN's Modular AUV

16 Sep 2019

MARIN is designing and building a modular autonomous underwater vehicle (mAUV). The vehicle will serve as a platform for research projects on ...
Magazine
MARIN develops a modular Autonomous Underwater Vehicle

13 Sep 2019

MARIN is designing and building a modular Autonomous Underwater Vehicle (mAUV) in order to gain a better understanding of the challenges involved in ...
Paper
Robust thrust allocation algorithm considering hydrodynamic interactions and actuator physical limitations

9 Nov 2018

The dynamic positioning (DP) system is responsible for the station keeping of vessels in several offshore operations. The forces required by the DP ...
Paper
Thruster-wave Interaction during DP Stationkeeping - Model Tests in Open Water and under a Ship Hull

25 Jun 2017

Wave orbital motions may cause variations in the inflow conditions of thrusters, resulting in variations in thrust and torque. Physical scale model ...
Paper
Determining Thruster-Hull Interaction for a Drill-Ship Using CFD

25 Jun 2017

In this paper CFD results are presented for the thrusterhull interaction effects for a drillship with 6 azimuthing thrusters. The results using ...
Magazine
Joint R&D in Offshore JIPs

22 Apr 2016

Reading time 6 minutes

The offshore industry works closely together to share knowledge, experience and costs. Here we give an update on the latest Joint Industry Projects. ...
Paper
Past, Present and Future of Hydrodynamic Research for DP Applications

1 Oct 2015

MARIN has been involved in model testing for DP vessels for almost 4 decades. In 1976 a first project was carried out in which the main propeller of ...
Paper
PIV Measurements in Thruster-interaction Research

1 Oct 2014

During DP operation the thrusters of the vessel counteract the wind, wave and current forces, so that the vessel can maintain its required position ...
Paper
An advanced thrust allocation algorithm for DP applications, taking into account interaction effects and physical limitations

8 Jun 2014

The Dynamic Positioning (DP) system is responsible for the stationkeeping and manoeuvrability of a vessel in offshore operations. The forces ...
Paper
Thruster-Interaction Effects on a DP Shuttle Tanker - Wake Flow Measurements of the Main Propeller and Bow Tunnel Thrusters

1 Jun 2014

This paper discusses thruster interaction effects for a DP shuttle tanker, equipped with two main propellers and rudders, as well as two bow tunnel ...
Paper
Thruster-interaction Effects on a DP Semi-submersible and a Drill Ship: Measurement and analysis of the thruster wake flow

9 Jun 2013

Thruster-interaction model tests were carried out in MARIN's Deepwater Towing Tank. Detailed PIV measurements were performed of the wake flow ...
Paper
The Wake Flow Behind Azimuthing Thrusters, Measurements in Open Water, Under a Plate and Under a Barge

1 Jul 2012

The wake flow behind a ducted azimuthing thruster was investigated. The thruster wake is an important factor in thruster interaction effects. Model ...
Magazine
Giant six-legged robot gives MARIN model the shakes

20 Apr 2012

Reading time 3 minutes

Headlines are of course, designed to grab the attention of the reader. But luckily all is not as it seems... Report introduces MARIN's new hexapod ...
Paper
A Generic Optimization Algorithm for the Allocation of DP Actuators

19 Jun 2011

In this paper we present a generic optimization algorithm for the allocation of dynamic positioning actuators, such as azimuthing thrusters and ...
Paper
An Innovative Oil Pollution Containment Method for Ship Wrecks Proposed for Offshore Well Blow-outs

19 Jun 2011

In the aftermath of the PRESTIGE disaster, an innovative system for the prompt intervention on oil pollution sources (primarily ship wrecks) at ...
Paper
The DIFIS System for Removal of Oil from Shipwrecks Evaluation of operational conditions, survival conditions and system deployment

1 Jan 2011

This paper describes a system for the recovery of oil from ship wrecks, even in very large water depths. The system is light-weight, completely ...
Paper
Analysis of the Velocities in the Wake of an Azimuthing Thruster, using PIV Measurements and CFD Calculations

12 Oct 2010

The wake flow behind a ducted azimuthing thruster was investigated, both in open water conditions and with the thruster placed under a schematical ...
Paper
DIFIS Concept for the Removal of Oil from Ship Wrecks - Hydrodynamic scale model tests for operational, survival and offloading conditions and system deployment

20 Jun 2010

DIFIS (Double Inverted Funnel for the Intervention on Ship wrecks) is a concept developed to recover hydrocarbons from ship wrecks, even in very ...
Magazine
New initiatives probe thruster interaction effects

26 Apr 2010

Reading time 9 minutes

MARIN has a long history in research into the performance of thrusters during Dynamic Positioning (DP) operations. Research on ducted propellers ...
Paper
Analysis of the tunnel immersion for the Busan-Geoje fixed link project through scale model tests and computer simulations

1 Jun 2009

In Korea a four lane motorway is constructed between the city of Busan and the island Geoje, reducing traveling times from 1 hour by ferry to just ...
Paper
Motions and Mooring Loads of an LNG-Carrier Moored at a Jetty in a Complex Bathymetry

1 Jun 2009

The Yemen LNG Company Ltd. is working on the design and construction of an LNG plant in the Republic of Yemen. The LNG plant, located at Balhaf on ...
Paper
On the Application of Selected Wave Group Spectra for the Experimental Investigation of Low Frequency Motions of a Moored Structure

1 Jun 2009

A moored structure shows both wave and low frequency motions in waves. Wave frequency motions are related to the wave elevation and wave power ...
Magazine
DP simulations and model testing - on the spot!

24 Apr 2009

Reading time 9 minutes

MARIN has a long history in Dynamic Positioning (DP) model testing and computer simulations. In recent years there has been increasing interest in ...
Magazine
MARIN contributes to unique Korean motorway project

29 Jan 2009

Reading time 3 minutes

In Korea, a four-lane motorway is being constructed between the city of Busan and Geoje island, reducing travelling times from one hour by ferry to ...
Paper
Model Testing and Complex Numerical Simulations for Offshore Installation

6 Jul 2008

This paper describes the analysis performed for the installation of two top-side modules on the Njord FPU by Saipem UK''s dynamically ...
Paper
Worst Sea - Best Sea Wave Group Spectra from Random Sea States

15 Jun 2008

The paper presents a proposition called the worst sea-best sea (WS-BS) method that intends to identify wave group spectra that yield time series ...
Paper
Recovery of Oil Trapped in Ship-Wrecks - the DIFIS Concept

1 May 2008

A method for the prompt and cost-effective intervention and remediation of tanker wrecks dealing with eventual leaks and recovering the fuel trapped ...
Magazine
MARIN tests two Prosafe FPSO's destined for Australia and Brazil

1 Apr 2008

Reading time 6 minutes

Prosafe was awarded two major contracts for the supply and operation of the Ningaloo Vision FPSO for Apache's Van Gogh field, offshore Australia and ...
Magazine
MARIN leads EU project for the prevention of environmental disasters

1 Apr 2008

Reading time 6 minutes

MARIN is project coordinator of the European research project Double Inverted Funnel for the Intervention on Shipwrecks (DIFIS), which aims to ...
Paper
Model Tests and Computer Simulations for Njord FPU Gas Module Installation

1 Mar 2008

Recently, two gas modules have been installed on the Njord FPU, on the Norwegian Continental Shelf, to enable gas exports from the Njord Field ...
Magazine
Deepwater FPSO for Brazil under scrutiny in MARIN's Offshore Basin

1 Apr 2007

Reading time 3 minutes

Model tests were recently carried out in MARIN's Offshore Basin for a turret-moored deepwater FPSO, to be installed offshore Brazil. Here is an ...
Paper
Heave, Roll and Pitch Damping of a Deepwater CALM Buoy with a Skirt

19 Jun 2005

The heave, roll and pitch damping of a CALM buoy contains linear contributions (wave radiation) and quadratic contributions (drag loads). The linear ...
Magazine
New publication on Deepwater CALM Buoy

1 Apr 2005

Reading time 2 minutes

A series of large-scale model tests on the behaviour of deepwater CALM buoys was recently carried out on behalf of Bluewater Energy Services in ...
Paper
Coupled Mooring Analysis for a Deep Water CALM Buoy

1 Jun 2004

The effect of the mooring loads on floater motions can be significant for small water plane area floaters like CALM buoys. Not only does the mooring ...
Magazine
Big Sweep model tests for Bluewater

1 Dec 2003

Reading time 2 minutes

MARIN carried out model tests on the Big Sweep LNG offloading system on behalf of Bluewater Energy Services. The Big Sweep concept consists of an ...
Magazine
Deepwater innovations offshore Brazil

1 Apr 2002

Reading time 3 minutes

Brazilian oil company Petrobras has been working together with the university COPEE/UFRJ in Rio de Janeiro on the development of the Sub Surface ...
Magazine
MARIN helps improve CALM buoy design

1 Apr 2002

Reading time 3 minutes

As the deepwater CALM buoy becomes a common solution for offloading from spread moored West of Africa FPSOs, MARIN is carrying out an increasing ...
Paper
Coupled Mooring Analysis in Large Scale Model Tests on a Deepwater CALM Buoy in Mild Wave Conditions

1 Jan 2002

This paper describes a series of model tests aimed at gaining insight in the tension variations in the export risers and mooring lines of a CALM ...
Paper
Important Environmental Modelling Aspects for Ultra Deep Water Model Tests

1 Oct 2001

Model testing for ultra deep water projects requires special attention to the modelling of waterdepth, wind, waves and current. Due to the large ...
Paper
Hydrodynamic Research Topics for DP Semi Submersibles

1 May 1999

The study of the behavior of dynamically positioned semi submersibles in the time domain can deliver important information on the positioning ...

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