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Delft University of Technology
1.
Achterberg, Massimo (author).
Modelling Markovian epidemic and information diffusion over adaptive networks.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:d2698130-e54b-4065-8f38-eba46dbb5eef 
► Modelling the spread of contagious diseases among people has been a research topic for over a hundred years. However, the increase in computation power in…
(more)
▼ Modelling the spread of contagious diseases among people has been a research topic for over a hundred years. However, the increase in computation power in the recent years allows for more advanced scientific models. The well-known susceptible-infected-susceptible model is used to describe the spreading of a disease among a group of people. This is modelled as a network, where persons are represented by nodes and their connections are links in the network. In this thesis, instead of a typical static network, the network itself changes structure based on the disease states of the nodes. In other words, there are two independent processes; the spreading of the disease over the network (state of the nodes) and the adaption of the network to the disease (state of the links). As a spreading model, the Markovian adaptive susceptible-infected-susceptible model (ASIS model for short) is introduced. It is shown that the model has one steady state, named the trivial steady state, in which all individuals are healthy. When the infection rate is sufficiently high, the system undergoes a phase transition from the disease-free state to an endemic state, where most nodes are infected. The state where most nodes are infected is named the metastable state. After being in the metastable state for a long time, the system collapses to the trivial steady state. The spreading of contagious processes is not just limited to disease spreading. Other relevant examples, such as opinion, gossip, fake news, neuron transmittance in the brain, etc. can be modelled using adaptive models as well. In this thesis, the ASIS model is extended by allowing different rules for the link-breaking and link-creation processes in what we call the Generalised ASIS framework. In total 36 models have been analysed simultaneously. Out of the 36 models, 9 showed a partially unstable metastable state. This resulted in rapid oscillations of the number of infected nodes just above the epidemic threshold. The relation between the epidemic threshold and the effective link-breaking rate was also determined. For 5 cases, the epidemic threshold is independent of the effective link-breaking rate. In 18 cases, the epidemic threshold scales linearly in the link-breaking rate. The remaining 13 cases are bounded between a constant and a linear link-breaking rate, however, its exact dependence remains unclear. In the G-ASIS framework, it was conjectured that the metastable state of the Markov process can be accurately approximated by the steady state of the mean-field approximation. It was shown this is not true for every model. However in the ASIS model, the mean-field approximation showed close resemblance to the averaged stochastic results. This may be caused by a positive correlation between the nodes. For the other models, the deviation from the mean field approximation can probably be contributed to the fact that nodes are not positively correlated. Other higher order mean field approximations should be examined to approximate the averaged behaviour of the Markov…
Advisors/Committee Members: Dubbeldam, Johan (mentor), Van Mieghem, Piet (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Adaptive; Network science; Information diffusion; Epidemiology
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APA (6th Edition):
Achterberg, M. (. (2019). Modelling Markovian epidemic and information diffusion over adaptive networks. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:d2698130-e54b-4065-8f38-eba46dbb5eef
Chicago Manual of Style (16th Edition):
Achterberg, Massimo (author). “Modelling Markovian epidemic and information diffusion over adaptive networks.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:d2698130-e54b-4065-8f38-eba46dbb5eef.
MLA Handbook (7th Edition):
Achterberg, Massimo (author). “Modelling Markovian epidemic and information diffusion over adaptive networks.” 2019. Web. 22 Jan 2021.
Vancouver:
Achterberg M(. Modelling Markovian epidemic and information diffusion over adaptive networks. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:d2698130-e54b-4065-8f38-eba46dbb5eef.
Council of Science Editors:
Achterberg M(. Modelling Markovian epidemic and information diffusion over adaptive networks. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:d2698130-e54b-4065-8f38-eba46dbb5eef
Delft University of Technology
2.
Bruijns, Lianne (author).
Optimization of User Equilibrium container transportation problems using toll pricing.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:056d28de-fe7e-48ae-8a9d-0af5bd9aa2c0
► The goal of this thesis is to provide a method to obtain a User Equilibrium (UE) in a synchromodal transportation network in which we transport…
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▼ The goal of this thesis is to provide a method to obtain a User Equilibrium (UE) in a synchromodal transportation network in which we transport containers for multiple customers. We use the Space Time Network (STN), in which the travel time of modalities is fixed and independent of the occupancy of the network. We define the User Equilibrium solution as the solution wherein each customer can travel via their cheapest paths possible, and no customer is harmed by the route choice of other customers. We define the System Optimal (SO) solution as the solution in which the total costs of the network are minimized. We expand the goal of finding a UE on the STN to finding a solution where the solution is both SO as well as UE. The solving method we developed in this thesis, consists of finding SO solutions by solving the Minimum Cost Multi-Commodity Flow (MCMCF) problem on the STN to find an SO solution, and create tolls schemes to create a UE solution, while maintaining the SO solution. We investigate several types of tolls in order to obtain sufficient both SO and UE solutions.
Applied Mathematics
Advisors/Committee Members: Aardal, Karen (mentor), Dubbeldam, Johan (graduation committee), Phillipson, F. (graduation committee), Sangers, A (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Optimization; User Equilibrium; Toll Pricing
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APA (6th Edition):
Bruijns, L. (. (2018). Optimization of User Equilibrium container transportation problems using toll pricing. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:056d28de-fe7e-48ae-8a9d-0af5bd9aa2c0
Chicago Manual of Style (16th Edition):
Bruijns, Lianne (author). “Optimization of User Equilibrium container transportation problems using toll pricing.” 2018. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:056d28de-fe7e-48ae-8a9d-0af5bd9aa2c0.
MLA Handbook (7th Edition):
Bruijns, Lianne (author). “Optimization of User Equilibrium container transportation problems using toll pricing.” 2018. Web. 22 Jan 2021.
Vancouver:
Bruijns L(. Optimization of User Equilibrium container transportation problems using toll pricing. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:056d28de-fe7e-48ae-8a9d-0af5bd9aa2c0.
Council of Science Editors:
Bruijns L(. Optimization of User Equilibrium container transportation problems using toll pricing. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:056d28de-fe7e-48ae-8a9d-0af5bd9aa2c0
Delft University of Technology
3.
Coppoolse, Taco (author).
Elastic registration of histological serial sections: A finite element approach.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:7d4d09be-81e1-498d-adcb-21b9ecb05411
► For a proper three-dimensional reconstruction of histology serial sections, adjustment of the slices is necessary for combining serial sections. Deformations occur due to the sectioning…
(more)
▼ For a proper three-dimensional reconstruction of histology serial sections, adjustment of the slices is necessary for combining serial sections. Deformations occur due to the sectioning and acquisition pro-cess of the microscopic analysis of histology. By reconstructing the deformations with a transformation of the sections, a mathematical correction on the images can be applied. By using image registration, a transformation function is searched for to minimize differences between the histology slices. Due to the non-linearity of the distortions, prior knowledge is required in order to have a solvable problem. Additional information in the form of elasticity regularisation is considered. Implementing the elastic regularisation with a finite element method, provides a continuous transformation function With the continuous function, in a natural way, alignment can be monitored for folding transformations. In this work, the (bi-)linear and (bi-)quadratic elements for the finite element method are implemented and compared with the finite difference method. It is observed that for the different kinds of elements, the (bi-)linear elements yield best results with the validity of the transformation. Moreover, the computa- tional costs for the bi-linear elements are the cheapest. Compared with the finite difference method, the differences in accuracy are not noteworthy but the computational time of the finite element method is longer. Furthermore, to steer the matching in an accurate direction, improvements are proposed by applying local stiffness of the elements or adding soft constraints on the volume of the elements. This results in significant improvements in the transformation. For these two approaches it is observed that local stiffness is more restrictive than volume-preserving. Solving the optimization problem, a Gauss-Newton method to search for descent directions is applied. A matrix-based and a matrix-free approach of elasticity regularisation is considered in the linear system of finding a descent direction. While the matrix-free approach decreases the memory usage, the computational costs are significantly increased.
Advisors/Committee Members: van Gijzen, Martin (mentor), Modersitzki, Jan (mentor), Dubbeldam, Johan (graduation committee), Remis, Rob (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Image Registration; Elastic Regularisation; Finite Element Method; Matrix-free
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APA (6th Edition):
Coppoolse, T. (. (2019). Elastic registration of histological serial sections: A finite element approach. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:7d4d09be-81e1-498d-adcb-21b9ecb05411
Chicago Manual of Style (16th Edition):
Coppoolse, Taco (author). “Elastic registration of histological serial sections: A finite element approach.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:7d4d09be-81e1-498d-adcb-21b9ecb05411.
MLA Handbook (7th Edition):
Coppoolse, Taco (author). “Elastic registration of histological serial sections: A finite element approach.” 2019. Web. 22 Jan 2021.
Vancouver:
Coppoolse T(. Elastic registration of histological serial sections: A finite element approach. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:7d4d09be-81e1-498d-adcb-21b9ecb05411.
Council of Science Editors:
Coppoolse T(. Elastic registration of histological serial sections: A finite element approach. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:7d4d09be-81e1-498d-adcb-21b9ecb05411
Delft University of Technology
4.
Dhiman, Ashish Kumar (author).
Measuring the robustness of network controllability.
Degree: 2020, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:76b1aaca-f1f6-4eb5-9fbb-fec2fe443f10
► Networks are all around us, telecommunication networks, road transportation networks, and the Internet are a few examples of networks that we encounter every day. The…
(more)
▼ Networks are all around us, telecommunication networks, road transportation networks, and the Internet are a few examples of networks that we encounter every day. The entities in a network are represented by nodes and the interconnections between them are represented by links. For example, in a telecommunication network, a node could be an end point for data transmission, a redistribution point or in physical terms, an entity that is capable of receiving, transmitting or redistributing information and a link could be a wired or a wireless connection between the nodes. It is of prime importance that the networks perform their functions properly. To ensure the effective operation of such networks, we need to control them by applying external inputs on some nodes which are known as driver nodes. We say that a network is controllable if it can be driven from any arbitrary state to any desired state in finite time under the control of driver nodes which are attached to the external inputs. Networks are often confronted with perturbations in the form of targeted and random attacks to disrupt their operation. Such perturbations make these networks less controllable. Thus, more driver nodes are needed to gain the full controllability of these networks. As a result, the robustness of network controllability decreases. In this study, the minimum number of driver nodes which gain full controllability after failures or attacks is chosen as the robustness metric. Existing closed-form analytical approximations estimate the normalized minimum number of driver nodes as a function of the fraction of removed links in both targeted and random attacks. However, the approximations sometimes do not fit with the simulations and the errors between the approximations and simulations are large. The main objectives of this study are to improve the analytical approximations using machine learning methods for both targeted and random attacks and additionally, derive a suitable analytical approximation for the out-in degree-based attack. Specifically, we use Linear Regression, Random Forest, and Artificial Neural Networks. To evaluate the performance of our machine learning models, we compare them with analytical approximations and simulations. In addition to this, we also study the attack based variability in estimating the minimum number of driver nodes using robustness envelopes. Based on the performance evaluations, we found that the approximations using machine learning models significantly outperform the existing closed-form analytical approximations for the minimum number of driver nodes, both in real-world and synthetic networks. Furthermore, we also assess the performance of our analytical approximations for the out-in degree-based attacks by comparing them with simulations.
Electrical Engineering | Telecommunications and Sensing Systems
Advisors/Committee Members: Kooij, Robert (mentor), Sun, Peng (mentor), Kitsak, Maksim (graduation committee), Dubbeldam, Johan (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Network controllability; Robustness; Targeted attacks; Random attacks; Machine Learning
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APA (6th Edition):
Dhiman, A. K. (. (2020). Measuring the robustness of network controllability. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:76b1aaca-f1f6-4eb5-9fbb-fec2fe443f10
Chicago Manual of Style (16th Edition):
Dhiman, Ashish Kumar (author). “Measuring the robustness of network controllability.” 2020. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:76b1aaca-f1f6-4eb5-9fbb-fec2fe443f10.
MLA Handbook (7th Edition):
Dhiman, Ashish Kumar (author). “Measuring the robustness of network controllability.” 2020. Web. 22 Jan 2021.
Vancouver:
Dhiman AK(. Measuring the robustness of network controllability. [Internet] [Masters thesis]. Delft University of Technology; 2020. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:76b1aaca-f1f6-4eb5-9fbb-fec2fe443f10.
Council of Science Editors:
Dhiman AK(. Measuring the robustness of network controllability. [Masters Thesis]. Delft University of Technology; 2020. Available from: http://resolver.tudelft.nl/uuid:76b1aaca-f1f6-4eb5-9fbb-fec2fe443f10
Delft University of Technology
5.
Hermans, Carlos (author).
Several approaches to model multi-commodity dynamical flow: on a package transport network.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:cb378d8b-02b9-42dd-812c-36556a0f6902
► This thesis investigates several kinds of models of describing multi-commodity dynamical flow. Three models have been developed for a spatial logistic network, on which packages…
(more)
▼ This thesis investigates several kinds of models of describing multi-commodity dynamical flow. Three models have been developed for a spatial logistic network, on which packages are delivered by vehicles and another model was developed to describe interactions between the customers, the stores and the deliverers, which does not explicitly take delivery time into account like before. The former three models consist of an agent-based model (ABM), and two different (differential) equation-based models (EBMs). One of the EBMs is built from the bottom up, and was created by averaging the randomness in the ABM. The other EBM was built top-down and involved optimizing a general model with respect to some parameters, such that its solution resembles the ABM solution as closely as possible. These three models were tested and compared in the first half of the thesis. In the second part of the thesis, the focus shifted to a generalized model (GM) approach of underlying interactions on multi-commodity dynamical flow networks; especially the dynamics describing order placement, scheduling and delivery. Such a network is cyclic and contains a feedback loop, where customers are less likely to order more products if they were recently delivered. This can range from someone not needing to purchase a car if they just bought a brand new one to one not needing to order dinner when they just did so. Such networks are in general described by four kinds of elasticities in this thesis, namely the elasticities to stock, inventory level, saturation, and co-production. These influence different parts in the network. For example, the negative elasticities to inventory level model that high inventory levels inhibit more inventory production, to prevent build-up, and low inventory levels allow for larger inventory production, to prevent drainage. The other elasticities fulfil similar roles. This model was tested using a bifurcation analysis, a statistical ensemble method and by computing influences and sensitivities of parts and nodes in the network.
Computational Science and Engineering
Advisors/Committee Members: Dubbeldam, Johan (mentor), Stam, Andries (mentor), Schuttelaars, Henk (graduation committee), van Essen, Theresia (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Agent-Based Modeling; Differential Equations; Generalized Models; Dynamical flow; Multi-commodity; Logistics; Bifurcation; Package transport
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APA ·
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APA (6th Edition):
Hermans, C. (. (2019). Several approaches to model multi-commodity dynamical flow: on a package transport network. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:cb378d8b-02b9-42dd-812c-36556a0f6902
Chicago Manual of Style (16th Edition):
Hermans, Carlos (author). “Several approaches to model multi-commodity dynamical flow: on a package transport network.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:cb378d8b-02b9-42dd-812c-36556a0f6902.
MLA Handbook (7th Edition):
Hermans, Carlos (author). “Several approaches to model multi-commodity dynamical flow: on a package transport network.” 2019. Web. 22 Jan 2021.
Vancouver:
Hermans C(. Several approaches to model multi-commodity dynamical flow: on a package transport network. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:cb378d8b-02b9-42dd-812c-36556a0f6902.
Council of Science Editors:
Hermans C(. Several approaches to model multi-commodity dynamical flow: on a package transport network. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:cb378d8b-02b9-42dd-812c-36556a0f6902
Delft University of Technology
6.
Jonker, Hendrik (author).
Valuation of natural gas storage contracts with the COS method.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:2a29f2c2-20c1-4a6e-8a7e-bb05662fd844
► Since the liberalization of the energy markets, the storage of energy is decoupled from the production and sales. In Western-Europe the storage of natural gas…
(more)
▼ Since the liberalization of the energy markets, the storage of energy is decoupled from the production and sales. In Western-Europe the storage of natural gas becomes more and more important because production fields get depleted and governments force companies to slow down their production because of tremors in the ground. Natural gas needs to be imported from countries that are far away, like for example Russia. To provide in security of supply and to ensure there is enough natural gas when the demand is high, it is important to store natural gas nearby. To determine the value of a gas storage facility in a reliable way we need an efficient market. For an efficient market is needed that the financial instruments, like futures contracts and options on natural gas, are liquidly traded on the exchange. If this condition is met, we are able to determine the value of storage according to market prices. The COS method was already presented as an efficient method for pricing a broad spectrum of financial derivatives and can be used in combination with all processes for the underlying for which a characteristic function is known. For processes whose characteristic function is not available, the adjoint expansion method can be used to obtain an approximation of the characteristic function. In this work the COS method will be presented as an efficient method for determining the value of gas storage contracts which is competitive with existing valuation methods for natural gas storage contracts.
Advisors/Committee Members: Oosterlee, Kees (mentor), Borovykh, Anastasia (mentor), Dubbeldam, Johan (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: COS method; Gas storage valuation; Adjoint expansion
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APA ·
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APA (6th Edition):
Jonker, H. (. (2019). Valuation of natural gas storage contracts with the COS method. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:2a29f2c2-20c1-4a6e-8a7e-bb05662fd844
Chicago Manual of Style (16th Edition):
Jonker, Hendrik (author). “Valuation of natural gas storage contracts with the COS method.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:2a29f2c2-20c1-4a6e-8a7e-bb05662fd844.
MLA Handbook (7th Edition):
Jonker, Hendrik (author). “Valuation of natural gas storage contracts with the COS method.” 2019. Web. 22 Jan 2021.
Vancouver:
Jonker H(. Valuation of natural gas storage contracts with the COS method. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:2a29f2c2-20c1-4a6e-8a7e-bb05662fd844.
Council of Science Editors:
Jonker H(. Valuation of natural gas storage contracts with the COS method. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:2a29f2c2-20c1-4a6e-8a7e-bb05662fd844
Delft University of Technology
7.
Pols, Daniel (author).
An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:923c9ff0-4777-4860-94f8-a92e5ec87af2
► In solving two-phase flows, the location of the interface between the phases is necessary to handle interface jump conditions when solving the Navier-Stokes equation. Current…
(more)
▼ In solving two-phase flows, the location of the interface between the phases is necessary to handle interface jump conditions when solving the Navier-Stokes equation. Current interface capturing and advection methods, however, suffer from various issues. The level set method uses the signed distance to the interface and the interface being the zero level set of this function allows the evolution of the level set field to be described with a simple advection equation. This means that no additional steps are required, but solving the advection equation generally does not conserve mass. On the other hand, Volume of Fluid methods utilise the local fluid fractions to represent the phase interface. For these methods, a mass conserving advection algorithm exists, but the absence of an explicit interface requires expensive reconstruction methods to be used instead. Additionally, this Volume of Fluid advection method is subject to a restrictive CFL condition on the time-step and, being dimensionally split, requires a structured grid to be used. Other Volume of Fluid or Moment of Fluid advection methods that do not have these conditions are not mass conserving. Dual interface methods that combine information from the level set and volume fractions are able to achieve higher accuracy, but these method still use Volume of Fluid advection to remain mass conserving and are thus subject to the same conditions. These methods use the level set field to create a cheaper and better justified reconstruction method, which negates one drawback of VoF methods. In this thesis, a method is formulated to allow interface advection on unstructured grids without such a strict CFL condition compared to the MCLS method. To do this, the finite volume level set advection method of the MCLS method is replaced with a nodal-modal discontinuous Galerkin method. The DG method is analogous to the Galerkin finite element methods, but the basis functions are now only valid on one element, and the solution can be multiply defined on the cell boundaries. This allows for level set advection on polygonal cells, and has the added benefit that since cells are semi-independent, level set correction now only has to be applied locally. This, like the finite volume level set advection method, is not necessarily mass conserving though, so the volume of fluid will need to solve this issue. The difference with MCLS is that no volume of fluid advection method is used, since these methods are the parts that introduce the aforementioned problems that are being avoided. Instead, a minimisation method is done on the VOF field in order to obtain a correction which can be applied to the level set and keep it mass conserving. For this minimisation method, a flux condition is used to impose additional constraints on the solution. This condition effectively attempts to match the interface intersections on a cell edge for both adjacent cells, for all cell edges that have a flux going through. The resulting method is tested for four test cases, with solid body translation and…
Advisors/Committee Members: van der Heul, Duncan (mentor), Vuik, Kees (graduation committee), Dubbeldam, Johan (graduation committee), Breugem, Wim-Paul (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Two-phase flow; Level Set Method; discontinuous Galerkin; Volume of fluid; Mass conserving
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APA ·
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APA (6th Edition):
Pols, D. (. (2019). An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:923c9ff0-4777-4860-94f8-a92e5ec87af2
Chicago Manual of Style (16th Edition):
Pols, Daniel (author). “An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:923c9ff0-4777-4860-94f8-a92e5ec87af2.
MLA Handbook (7th Edition):
Pols, Daniel (author). “An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids.” 2019. Web. 22 Jan 2021.
Vancouver:
Pols D(. An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:923c9ff0-4777-4860-94f8-a92e5ec87af2.
Council of Science Editors:
Pols D(. An innately mass conserving interface capturing method for the modelling of interface advection on unstructured grids. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:923c9ff0-4777-4860-94f8-a92e5ec87af2
Delft University of Technology
8.
Ringlever, Terry (author).
The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction.
Degree: 2018, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:76fdd01c-9376-41c2-a0d0-6bae2f6bf954
► The phenomenon of cluster synchronization in ring networks is studied in the first part of this thesis by means of Representation Theory. The second part…
(more)
▼ The phenomenon of cluster synchronization in ring networks is studied in the first part of this thesis by means of Representation Theory. The second part of this thesis is devoted to the determination of the size of the Basin of Attraction for a stable node.
Advisors/Committee Members: Dubbeldam, Johan (mentor), van der Woude, Jacob (graduation committee), van der Heul, Duncan (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Cluster synchronization; Representation; Basin of Attraction; Kuramoto model
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APA (6th Edition):
Ringlever, T. (. (2018). The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:76fdd01c-9376-41c2-a0d0-6bae2f6bf954
Chicago Manual of Style (16th Edition):
Ringlever, Terry (author). “The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction.” 2018. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:76fdd01c-9376-41c2-a0d0-6bae2f6bf954.
MLA Handbook (7th Edition):
Ringlever, Terry (author). “The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction.” 2018. Web. 22 Jan 2021.
Vancouver:
Ringlever T(. The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction. [Internet] [Masters thesis]. Delft University of Technology; 2018. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:76fdd01c-9376-41c2-a0d0-6bae2f6bf954.
Council of Science Editors:
Ringlever T(. The Kuramoto model on ring networks: Cluster synchronization and the size of the Basin of Attraction. [Masters Thesis]. Delft University of Technology; 2018. Available from: http://resolver.tudelft.nl/uuid:76fdd01c-9376-41c2-a0d0-6bae2f6bf954
Delft University of Technology
9.
Rozendaal, Marco (author).
An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea.
Degree: 2019, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:edc2ffd6-00fd-4cd6-883b-13b14528cb72
► Tidal inlet systems are often highly valuable and sometimes even unique ecosystems. However, field measurements show that tidal inlet systems are sensitive to changing exogenous…
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▼ Tidal inlet systems are often highly valuable and sometimes even unique ecosystems. However, field measurements show that tidal inlet systems are sensitive to changing exogenous conditions, such as rising sea levels. This thesis aims to investigate to what extent the adjacent sea influences the stability and equilibrium state of the tidal inlet. A one-dimensional idealised model is used to model the interaction between the sea and the inlet. The water motion is forced by the tide and the inlet is assumed to be narrow and short. At equilibrium, an increasingly sloping bottom is found in the sea and a constantly sloping bottom in the inlet. This equilibrium bottom profile seems to be in reasonable agreement with observations. The sea-inlet bottom profile is less stable than the inlet bottom profile, nevertheless, the sea-inlet bottom profile is still asymptotically linear stable. Moreover, the results in this thesis suggest that for one-dimensional idealised models consisting solely of a tidal inlet, the correct seaward boundary condition is a properly chosen fixed entrance depth. For a two-dimensional semi-infinite sea, it is shown that a Perfectly Matched Layer is a convenient method to incorporate the Sommerfeld radiation condition and that the narrow tidal inlet cannot be modelled as a point source forcing in the two-dimensional sea domain.
Applied Mathematics
Advisors/Committee Members: Schuttelaars, Henk (mentor), Dubbeldam, Johan (graduation committee), Möller, Matthias (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: Morphodynamic model; Idealised model; Tidal inlet system; Tidal embayment; Morphodynamic equilibrium; Equilibrium bed profiles; Stability analysis
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APA ·
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CSE |
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APA (6th Edition):
Rozendaal, M. (. (2019). An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:edc2ffd6-00fd-4cd6-883b-13b14528cb72
Chicago Manual of Style (16th Edition):
Rozendaal, Marco (author). “An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea.” 2019. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:edc2ffd6-00fd-4cd6-883b-13b14528cb72.
MLA Handbook (7th Edition):
Rozendaal, Marco (author). “An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea.” 2019. Web. 22 Jan 2021.
Vancouver:
Rozendaal M(. An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea. [Internet] [Masters thesis]. Delft University of Technology; 2019. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:edc2ffd6-00fd-4cd6-883b-13b14528cb72.
Council of Science Editors:
Rozendaal M(. An Idealised Morphodynamic Model of a Tidal Inlet and the Adjacent Sea. [Masters Thesis]. Delft University of Technology; 2019. Available from: http://resolver.tudelft.nl/uuid:edc2ffd6-00fd-4cd6-883b-13b14528cb72
Delft University of Technology
10.
van der Geugten, Gerald (author).
Predicting the sea surface from high resolution multi-beam FMCW radar data.
Degree: 2020, Delft University of Technology
URL: http://resolver.tudelft.nl/uuid:1ba166c4-2656-4f39-a250-eec61258838c
► In this thesis a deterministic wave model is used to reconstruct and predict the sea surface motion from FMCW (Frequency Modulated Continuous Wave) radar data,…
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▼ In this thesis a deterministic wave model is used to reconstruct and predict the sea surface motion from FMCW (Frequency Modulated Continuous Wave) radar data, produced by Radac. The deterministic model that is used to do this is based on the linear wave theory. The radar is looking horizontally straight towards the waves in 5 separate beam directions of -40,-20,0, 20 and 40 degrees. Using the FMCW principle the backscatterd signal is converted into velocity and spatial range information. After some compensations (current for example) this velocity data can be treated as horizontal component of the orbital velocity of the wave. By using a least-squares solving approach (the trust-region reflective algorithm) on these orbital velocities and the expression that holds for them in the linear wave theory the model can be fitted to the measurements. The result of the least squares solver consists of a set of parameters for wave amplitude, phase and frequency. With these parameters the deterministic motion of the sea surface can be computed. This method is tested using artificial data and a generalized one directional case (using information from 1 beam under assumption of infinitely long-crested waves). For the experiments with artificial data consisting of waves with Hs = 2 meters (significant waveheight) the results are promising. A prediction time of 30 seconds over a range of 150 meters with an average error of 15 cm in the one directional model (fitted on 10 second data over 384 meters) can be achieved. For the multi directional model this lies between 20 and 30 seconds with an average error of 25 cm, depending on the spreading of the waves. Experiments with real data show less impressive results, an accurate reconstruction of the surface can be given, but the predictive capability is very limited.
Applied Mathematics | Applied Physics
Advisors/Committee Members: Heemink, Arnold (mentor), van der Vlugt, Rolf (mentor), Dubbeldam, Johan (graduation committee), van Gijzen, Martin (graduation committee), Delft University of Technology (degree granting institution).
Subjects/Keywords: FMCW radars; Sea Modelling; Inverse Modelling
Record Details
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Record Details
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❌
APA ·
Chicago ·
MLA ·
Vancouver ·
CSE |
Export
to Zotero / EndNote / Reference
Manager
APA (6th Edition):
van der Geugten, G. (. (2020). Predicting the sea surface from high resolution multi-beam FMCW radar data. (Masters Thesis). Delft University of Technology. Retrieved from http://resolver.tudelft.nl/uuid:1ba166c4-2656-4f39-a250-eec61258838c
Chicago Manual of Style (16th Edition):
van der Geugten, Gerald (author). “Predicting the sea surface from high resolution multi-beam FMCW radar data.” 2020. Masters Thesis, Delft University of Technology. Accessed January 22, 2021.
http://resolver.tudelft.nl/uuid:1ba166c4-2656-4f39-a250-eec61258838c.
MLA Handbook (7th Edition):
van der Geugten, Gerald (author). “Predicting the sea surface from high resolution multi-beam FMCW radar data.” 2020. Web. 22 Jan 2021.
Vancouver:
van der Geugten G(. Predicting the sea surface from high resolution multi-beam FMCW radar data. [Internet] [Masters thesis]. Delft University of Technology; 2020. [cited 2021 Jan 22].
Available from: http://resolver.tudelft.nl/uuid:1ba166c4-2656-4f39-a250-eec61258838c.
Council of Science Editors:
van der Geugten G(. Predicting the sea surface from high resolution multi-beam FMCW radar data. [Masters Thesis]. Delft University of Technology; 2020. Available from: http://resolver.tudelft.nl/uuid:1ba166c4-2656-4f39-a250-eec61258838c
. 
Open Access Theses and Dissertations