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Exploiting Symmetry in the Generation Expansion Planning Problem to Accelerate Crossover: Determining European Energy Investment Strategies Faster

Arnoldus, Matthijs (author)

Computational efficiency is essential for large-scale mathematical optimisation problems, such as the generation expansion planning problem, to be practically applicable. In linear programming solvers, crossover is frequently a bottleneck when solving optimisation problems. This study aims at determining why crossover is a bottleneck in solving...

master thesis 2024

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On the Edge: A study into social integration within community boundaries

Chen, Deying (author)

This research paper focuses on the phenomenon of social and urban morphological contrasts within community boundaries caused by socioeconomic inequality and the process of urban development. This paper also discusses the reason and the spatial needs for social integration. This topic is becoming increasingly relevant in London because of the...

master thesis 2023

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Design and evaluation of a passive dynamic arm support for Robotic Assisted Laparoscopic Surgery

Schrijvershof, Pim (author)

Background : Surgeons performing robotic-assisted laparoscopic surgery experience physical stress and overuse of shoulder muscles due to sub-optimal arm support during surgery. Following background literature research on passive<br/>dynamic arm supports, this report presents and evaluates a novel design.<br/>Objective: To present a novel design...

master thesis 2023

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Crossover-effects in technical skills between laparoscopy and robot-assisted surgery

Hardon, S.F. (author), Willuth, E. (author), Rahimi, A. Masie (author), Lang, F. (author), Haney, Caelan M. (author), Felinska, Eleni A. (author), Kowalewski, Karl Friedrich (author), Müller-Stich, Beat P. (author), van der Peet, Donald L. (author), Daams, Freek (author), Nickel, F. (author), Horeman, T. (author)

Introduction: Robot-assisted surgery is often performed by experienced laparoscopic surgeons. However, this technique requires a different set of technical skills and surgeons are expected to alternate between these approaches. The aim of this study is to investigate the crossover effects when switching between laparoscopic and robot-assisted...

journal article 2023

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Lyapunov-Based Model Predictive Control for Stable Operation of a 9-Level Crossover Switches Cell Inverter in Grid Connection Mode

Trabelsi, Mohamed (author), Makhamreh, Harnza (author), Alquennah, Alamera Nouran (author), Vahedi, H (author)

This study proposes the application of a Lyapunov-based Model Predictive Control (L-MPC) approach to a 9-level Crossover Switches Cell (CSC9) converter operating in grid connection mode. The proposed method utilizes the structure of the classical finite-control-set MPC (FCS-MPC) technique while integrating a cost function that requires no tuning...

conference paper 2023

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Transient modelling of a multi-cell alkaline electrolyzer for gas crossover and safe system operation

Oikonomidis, Silvestros (author), Ramdin, M. (author), Moultos, O. (author), Bos, Albert (author), Vlugt, T.J.H. (author), Rahbari, A. (author)

Due to the intermittency of renewable energy sources, alkaline water electrolyzers are typically operated at partial load compared to the nominal design value. It is well-known that gas crossover is dominant at low current densities leading to higher anodic hydrogen content and higher cathodic oxygen content in the separator tanks. High...

journal article 2023

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Modeling gas crossover in alkaline water electrolysers

OIKONOMIDIS, SILVESTROS (author)

Climate change due to the extensive use of fossil fuels has led to the deployment of alternative green ones, such as hydrogen. Green hydrogen is produced by renewable electricity and is CO₂-free. This thesis focuses on the production of hydrogen by implementing alkaline water electrolysis as the core technology.  <br/>Due to the...

master thesis 2022

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Transient modeling and control of a small-scale and self-pressurized electrolysis system

Daniil, Ilias (author)

Zero Emission Fuels B.V. (ZEF) is a start-up company developing a fully autonomous methanol synthesis micro-plant that will be energy driven by solar panels. The process implements an alkaline water electrolyzer, which supplies the methanol synthesis reactor with hydrogen. The electrolysis system includes a small-scale stack of cells and is...

master thesis 2021

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High Indirect Energy Consumption in AEM-Based CO₂Electrolyzers Demonstrates the Potential of Bipolar Membranes

Blommaert, M.A. (author), Subramanian, S.S. (author), Yang, K. (author), Smith, W.A. (author), Vermaas, D.A. (author)

Typically, anion exchange membranes (AEMs) are used in CO2 electrolyzers, but those suffer from unwanted CO2 crossover, implying (indirect) energy consumption for generating an excess of CO2 feed and purification of the KOH anolyte. As an alternative, bipolar membranes (BPMs) have been suggested, which mitigate the reactant loss by...

journal article 2021

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Hybrid Multi-level Crossover for Unit Test Case Generation

Olsthoorn, Mitchell (author), Derakhshanfar, P. (author), Panichella, A. (author)

State-of-the-art search-based approaches for test case generation work at test case level, where tests are represented as sequences of statements. These approaches make use of genetic operators (i.e., mutation and crossover) that create test variants by adding, altering, and removing statements from existing tests. While this encoding schema has...

conference paper 2021

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Controlled Removal of Trace O2 in an H2 Environment of a Small-scale Electrolyser

Schwarze, Xander (author)

Power-to-gas (PtG) technology represents a promising route in providing long-term energy security and involves pairing volatile sources of renewable energy (solar and wind energy) with alkaline water electrolysis (AWE) to create a wide range of products based on intermediate hydrogen gas for end-users across various industries such as in fuels,...

master thesis 2020

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Reduced Ion Crossover in Bipolar Membrane Electrolysis via Increased Current Density, Molecular Size, and Valence

Blommaert, M.A. (author), Verdonk, J.A.H. (author), Blommaert, Hester C.B. (author), Smith, W.A. (author), Vermaas, D.A. (author)

A bipolar membrane (BPM) can be used to accelerate water dissociation to maintain a pH gradient in electrochemical cells, providing freedom to independently optimize the environments and catalysts used for paired reduction and oxidation reactions. The two physical layers in a BPM, respectively, selective for the exchange of cations and anions...

journal article 2020

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On the effect of laser altimeter crossover observables on orbit determination with the JUICE mission as case study

Villamil, Sebastian (author)

This thesis' work aims to evaluate the potential added benefit to spacecraft orbit determination procedures upon using non-conventional measurements for orbit reconstruction. As a spacecraft orbits a celestial body, its ground tracks will naturally cross previous ground tracks at many points. These locations, known as crossover points, yield...

master thesis 2019

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Rheological, fatigue and relaxation properties of aged bitumen

Jing, R. (author), Varveri, Aikaterini (author), Liu, X. (author), Scarpas, Athanasios (author), Erkens, S. (author)

Bitumen ageing has a significant impact on the mechanical performance of asphalt concrete. This study utilises dynamic mechanical tests (frequency sweep, fatigue, and relaxation) to investigate the effect of ageing on the viscoelastic characteristics of bitumen. As ageing progressed, a shift of the Black diagrams curves towards lower phase...

journal article 2019

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Enhanced Separation Concept (ESC): Removing the Functional Subunit from the Electrode by Molecular Design

Brandl, Thomas (author), El Abbassi, M. (author), Stefani, D. (author), Frisenda, R. (author), Harzmann, Gero D. (author), van der Zant, H.S.J. (author), Mayor, Marcel (author)

A new concept to improve the reliability of functional single molecule junctions is presented using the E-field triggered switching of Fe^IIbis-terpyridine complexes in a mechanically controlled break junction experiment as model system. The complexes comprise a push-pull ligand sensing the applied E-field and the resulting...

journal article 2019

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An Investigation into the Effects of Eye Activity on Human Perceptual Remnant and Control

Popovici, A. (author)

master thesis 2016

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Design with benefits: Hearth fire nights and bittersweet chores

Boess, S.U. (author), Pohlmeyer, A.E. (author)

conference paper 2016

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Finding performance measures of a centre of mass-controlled visual tracking task: A new method

Van der Gugten, D. (author)

This study focused on a new method to find accurate performance measures of a mediolateral centre of mass(CoM)-controlled visual tracking task, which might be sensitive enough to detect problems in balance control early on. Visual tracking tasks, controlled by mediolateral CoM displacement, have shown promising results in this respect. The task...

master thesis 2015

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Modulating crossover positioning by introducing large structural changes in chromosomes

Ederveen, A. (author), Lai, Y. (author), Van Driel, M.A. (author), Gerats, T. (author), Peters, J.L. (author)

Background Crossing over assures the correct segregation of the homologous chromosomes to both poles of the dividing meiocyte. This exchange of DNA creates new allelic combinations thus increasing the genetic variation present in offspring. Crossovers are not uniformly distributed along chromosomes; rather there are preferred locations where...

journal article 2015

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Performance of Crossovers in the Dutch Railway Network: Case Study for Amsterdam and Rotterdam

Hoeffelman, M.L. (author)

ProRail Traffic Control would like to have examined what the performance of crossovers for rescheduling is in case of partial obstructions. The need for quantitative information about the performance of crossovers in The Netherlands has grown. The research is intended to fill this knowledge gap by investigating the performance of crossovers in...

master thesis 2012