Austenite stabilization at room temperature in medium Mn DP steels through CPPT

The presence of retained austenite (RA) has been proven beneficial for the formability of Advanced High Strength Steels. Therefore, multiple thermal austenite stabilization methods have been researched, such as Mn-partitioning during intercritical annealing in medium Mn steels. The Cyclic Partial Phase Transformation (CPPT) approach has been...

Dynamic Positioning around an alternative control point

Traditionally, the control point (CP) of a dynamically positioned vessel is located around its center of gravity (CoG). However, during offshore operations, other locations, such as the crane tip or gripper position, become more critical due to the load being located there. This thesis proposes shifting the control point from the CoG to an...

Adaptive Nonlinear Domain Decomposition Methods with an Application to the p-Laplacian

In this article, different nonlinear domain decomposition methods are applied to nonlinear problems with highly heterogeneous coefficient functions with jumps. In order to obtain a robust solver with respect to nonlinear as well as linear convergence, adaptive coarse spaces are employed. First, as an example for a nonlinearly left...

Workability optimisation of the Stella Synergy: during monopile installation with a motion-compensated gripper and using its DP-system

Using a floating vessel operating on its DP-system and using a motion-compensated pile gripper to install monopiles could be the installation method of the future. Therefore, this thesis focuses on this method. The main objective of this thesis project is to build a model that accurately describes the motions of the Stella Synergy, the monopile,...

Laser-beam welding as a method to characterise in-situ local thermo-mechanical conditions leading to liquid zinc embrittlement of Dual-Phase steel

Liquid metal embrittlement (LME) is a problem encountered in the resistance spot welding joining process of advanced high-strength steels in the automotive industry. Its occurrence reduces the mechanical performance of welds. The nature of resistance spot welding prevents in-situ characterisation of thermo-mechanical conditions causing LME....

A Switching Control Perspective on the Offshore Construction Scenario of Heavy-Lift Vessels

Position control for heavy-lift construction vessels is crucial for safe operation during offshore construction. During the various phases of a typical offshore construction assignment, considerable changes in the dynamics of the crane-vessel system occur. Operational hazard was reported if such interchanging dynamics are not properly handled...

Acid etching as a surface pre-treatment step for PVD coatings on high strength steels

Coating deposition by Physical Vapour Deposition (PVD) on high strength steels is an important research project at TATA Steel - IJmuiden. The research is aimed at replacing the conventional hot-dip galvanisation process to obtain a defect-free coating without affecting their well-engineered properties. However, the annealing treatment of the...

The effect of ultra-fast heating on the microstructure, grain size and texture evolution of a commercial low-C, medium-Mn DP steel

The effect of ultra-fast heating on the microstructures of steel has been thoroughly studied over the last year as it imposes a suitable alternative for the production of ultra high strength steel grades. Rapid reheating followed by quenching leads to fine-grained mixed microstructures. This way the desirable strength/ductility ratio can be...

How good is good enough in DP calculations?: A case study into uncertainties involved in the DP capability prediction process

Currently there are three methods of calculating the Dynamic Positioning capability of a vessel namely: static calculations, real-time time domain simulations and fast-time time domain simulations, although the outcome of the last two should be identical. In each of these methods a set of input variables is required to perform the calculations....

What makes long DNA short?: Modulation of DNA structure by Dps protein: cooperating & reorganizing

Each confined cell created by nature and containing DNA molecule falls into the category of “alive organism”. All information about this organism is encoded in DNA molecule in genes, except of fate only. Along with the DNA molecule that represents genetic carrier, the organism neither the genome could function without proteins. Proteins are the...

Improving the energy efficiency, emissions and maintenance costs of a deepwater DP-3 drillship by implementing an energy storage system in the energy distribution system

Deepwater drillships are nowadays capable of drilling to oil in water depths up to 4000m and reservoirs at 12000 m depth and greater. Active Heave Compensation at these large drilling depths and station keeping with the Dynamic Positioning system leads to large fluctuations in the electrical power system. The electrical power is now directly...

Challenging the stress: A single-cell study of the Dps response

Hysteresis in DNA compaction by Dps is described by an ising model

In all organisms, DNA molecules are tightly compacted into a dynamic 3D nucleoprotein complex. In bacteria, this compaction is governed by the family of nucleoid-associated proteins (NAPs). Under conditions of stress and starvation, an NAP called Dps (DNA binding protein from starved cells) becomes highly up-regulated and can massively...

Influence of the Microstructure of the Corrosion Performance of DP Steels

Weight reduction of car bodies can be achieved by application of steel components with a lower thickness; however mechanical properties (for constructive and safety reasons) must be maintained, which can be achieved by using (U)HSS steels. These steels have been designed and optimized for improved mechanical behavior and therefore normally have...

Using Distributed Fiber-Optic Sensing Systems to Estimate Inflow and Reservoir Properties

Recent developments in the deployment of distributed fiber-optic sensing systems in horizontal wells carry the promise to lead to a new, cheap and reliable way of monitoring production and reservoir performance. Practical applicability of distributed pressure sensing for quantitative inflow detection will strongly depend on the specifications of...

Micromechanisms of Failure under Static Loading in Sheet Metals for Automotive Applications

Iron-Storage Mechanism of Ferritin

Storage of Fe(III) is a common mechanism by which the cellular machinery controls the availability of Fe(II) and Fe(III) for biosynthesis of iron-containing cofactors of enzymes which are involved in several essential biological processes, including oxidative phosphorylation. The conserved 24-meric iron-storage protein ferritin has been...

Optimal Thrust Allocation Methods for Dynamic Positioning of Ships

The first Dynamic Positioning (DP) systems emerged in the 1960's from the need for deep water drilling by the offshore oil and gas industry, as conventional mooring systems, like a jack-up barge or an anchored rig, can only be used in shallow waters. GustoMSC has been developing DP drill ships since the early 1970's and it is still one of their...