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Policy Innovation in the Heat Transition: Assessing Policy Innovation in the Sustainable Heating Transition in the Dutch Built Environment

Spoelstra, Siemen (author)

This master's thesis explores the role of policy innovation of policies, programs, and policy instruments within the domain of heat transition in the built environment in the Netherlands, focusing specifically on the role of municipalities in navigating this complex transition towards a natural gas-free future by 2050, as mandated by the...

master thesis 2024

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The lignocellulose binding phenomena and interlaminar fracture toughness of living Ganoderma lucidum

Spoelstra, Linde (author)

Mycelium based composites (MBC) have revolutionised the field of material production, where a living fungus is employed to overgrow and bind lignocellulosic substrate materials together. Their bio-based nature, low embodied energy, and biodegradability, mark their great potential to reduce the increasing pressure conventional materials put on...

master thesis 2023

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On-site aerodynamics investigation of speed skating

Spoelstra, A.M.C.M.G. (author), Terra, W. (author), Sciacchitano, A. (author)

An aerodynamic assessment is presented of two elite skaters, each in two different skating postures, at the ice-rink Thialf in Heerenveen, the Netherlands, via on-site Ring of Fire (RoF) measurements. This experimental approach adopts stereoscopic Particle Image Velocimetry (Stereo-PIV) to measure the flow upstream and downstream of the...

journal article 2023

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Aerodynamic benefits of drafting in speed skating: Estimates from in-field skater's wakes and wind tunnel measurements

Terra, W. (author), Spoelstra, A.M.C.M.G. (author), Sciacchitano, A. (author)

The effect of drafting on the aerodynamic drag of a long-track speed skater is investigated in-field, at the 400m ice-rink of Thialf, Heerenveen. The Ring of Fire system is used to measure the flow downstream of an elite, isolated skater at approximately 11 m/s, transiting repeatedly through a tunnel filled with Helium-filled soap bubble flow...

journal article 2023

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Ring of fire as a novel approach to study cycling aerodynamics

Spoelstra, A.M.C.M.G. (author)

The research presented in this thesis introduces a new measurement concept for on-site aerodynamic measurements based on large-scale stereoscopic particle image velocimetry (stereo-PIV) measurements past an athlete, a vehicle or an object travelling through a quiescent environment. The analysis of the momentumdeficit past the transit poses the...

doctoral thesis 2022

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On-site drag analysis of drafting cyclists

Spoelstra, A.M.C.M.G. (author), Sciacchitano, A. (author), Scarano, F. (author), Mahalingesh, Nikhil (author)

The aerodynamic drag of a trailing cyclists in a tandem formation is investigated at different lateral and longitudinal separations. A Ring of Fire (RoF) experiment is conducted at the Tom Dumoulin bike park of Sittard-Geleen in the Netherlands. The method is based on stereoscopic Particle Image Velocimetry (Stereo-PIV) measurements followed...

journal article 2021

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Inclusion through proactive public services: Findings from the Netherlands: Classifying and designing proactivity through understanding service eligibility and delivery processes

Bharosa, Nitesh (author), Oude Luttighuis, S.F. (author), Spoelstra, Flori (author), van der Voort, H.G. (author), Janssen, M.F.W.H.A. (author)

The COVID-19 pandemic highlights the dependence on digital public service delivery in many nations. The intensified use of digital public services also shifted the spotlight to accessibility and reactive design of digital public services. Inspired by the high level of proactivity provided in commercial digital services, policy-makers are looking...

conference paper 2021

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Quality assessment and quality control system for armourstones; by the use of simple testing tools

Spoelstra, Jelle (author)

Several waterway protection structures in the Netherlands dealt with rapid degrading armourstone after construction. This suggests that the current selection procedure of armourstones is not flawless to all degradation mechanisms, especially in dynamic environments. In this work armourstone is meant to include all rock that is used in river,...

master thesis 2020

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Uncertainty assessment of the Ring of Fire concept for on-site aerodynamic drag evaluation

Spoelstra, A.M.C.M.G. (author), Hirsch, Maximilian (author), Sciacchitano, A. (author), Scarano, F. (author)

The Ring of Fire (RoF) measurement concept to perform on-site experiments of aerodynamic drag for transiting objects is investigated with a study that identifies the main sources of uncertainty. The main contributors to the uncertainty of the drag measurement are examined for the case of a cyclist riding through the measurement domain. A...

journal article 2020

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Drafting Effect in Cycling: On-Site Aerodynamic Investigation by the ‘Ring of Fire'

Spoelstra, A.M.C.M.G. (author), Mahalingesh, N. (author), Sciacchitano, A. (author)

An on-site Ring of Fire (RoF) experiment is performed at the Tom Dumoulin bike park in Sittard-Geleen, the Netherlands. The current work investigates the aerodynamic drag of a cyclist following a lead cyclist at different lateral and longitudinal separations; additionally, the athletes’ skills to maintain their position and distance with respect...

journal article 2020

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Nonspherical Coacervate Shapes in an Enzyme-Driven Active System

Spoelstra, W.K. (author), van der Sluis, E.O. (author), Dogterom, A.M. (author), Reese, L. (author)

Coacervates are polymer-rich droplets that form through liquid-liquid phase separation in polymer solutions. Liquid-liquid phase separation and coacervation have recently been shown to play an important role in the organization of biological systems. Such systems are highly dynamic and under continuous influence of enzymatic and chemical...

journal article 2020

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On-site cycling drag analysis with the Ring of Fire

Spoelstra, A.M.C.M.G. (author), de Martino Norante, Luigi (author), Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)

Abstract: The Ring of Fire (RoF) measurement concept, introduced by Terra et al. (Exp Fluids 58:83. https://doi.org/10.1007/s00348-017-2331-0, 2017; Experiments in Fluids 59:120, 2018), is applied to real cyclists to enable the aerodynamic drag determination during sport action. This principle is based on large-scale stereoscopic particle...

journal article 2019

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Expertgroep City Distribution: De toekomst is dichterbij dan je denkt

Nelck, Anne-Marie (author), Sosef, Dirk (author), Zeeman, Dorine (author), Walvisch, Mick (author), Elsenaar, Erik Jan (author), Rodenburg, Paul (author), Lammers, Gerdwin (author), van Schaijk, Pieter (author), Quak, Hans (author), Havelaar, Rogier (author), van den Bosch, Jaap (author), Brinkhof, Rogier (author), Jongeneel, Joeri (author), van Duin, Ron (author), Dekker, Johan (author), Donkersloot, Vincent (author), Spoelstra, Jop (author), Boverhof, Willem (author), Sijtsma, Micha (author), van Hofwegen, Tom (author), Nieuwkerk, Michiel (author), van Gompel, Luc (author)

1. Een Urban Consolidation Centre (UCC) maakt het mogelijk om de stad zero-emissie te beleveren en zorgt ervoor dat goederen gebundeld de stad in gaan. Met als doel het minder belasten van klimaat, gezondheid van mensen en leefbaarheid van de stad. 2. Het UCC is een multimodaal overslagpunt, geschikt voor een variëteit aan voertuigen....

book chapter 2019

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Spatiotemporal control of coacervate formation within liposomes

Deshpande, S.R. (author), Brandenburg, Frank (author), Lau, A.W.H.R. (author), Last, M.G.F. (author), Spoelstra, W.K. (author), Reese, L. (author), Wunnava, Sreekar (author), Dogterom, A.M. (author), Dekker, C. (author)

Liquid-liquid phase separation (LLPS), especially coacervation, plays a crucial role in cell biology, as it forms numerous membraneless organelles in cells. Coacervates play an indispensable role in regulating intracellular biochemistry, and their dysfunction is associated with several diseases. Understanding of the LLPS dynamics would...

journal article 2019

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The Ring of Fire for in-Field Sport Aerodynamic Investigation

Spoelstra, A.M.C.M.G. (author), Terra, W. (author), Sciacchitano, A. (author)

A novel measurement system, the Ring of Fire, is deployed which enables the aerodynamic drag estimation of transiting cyclists. The system relies upon the use of large-scale stereoscopic PIV and the conservation of momentum within a control volume in a frame of reference moving with the athlete. The rider cycles at a velocity of approximately 8...

conference paper 2018

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An assessment of the Ring of Fire approach for indoor and outdoor on-site sports aerodynamic investigation

Spoelstra, A.M.C.M.G. (author), de Martino Norante, Luigi (author), Terra, W. (author), Sciacchitano, A. (author), Scarano, F. (author)

A procedure is proposed to reconstruct the instantaneous velocity field from full particle trajectories in a data assimilation framework that includes the vorticity transport equation. The technique is christened as time-segment assimilation (TSA). The work addresses the common problem of low seeding concentration in 3D experiments, usuallThe...

conference paper 2018

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Mechanical Division of Cell-Sized Liposomes

Deshpande, S.R. (author), Spoelstra, W.K. (author), van Doorn, M.C. (author), Kerssemakers, J.W.J. (author), Dekker, C. (author)

Liposomes, self-assembled vesicles with a lipid-bilayer boundary similar to cell membranes, are extensively used in both fundamental and applied sciences. Manipulation of their physical properties, such as growth and division, may significantly expand their use as model systems in cellular and synthetic biology. Several approaches have been...

journal article 2018

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Tailoring the appearance: what will synthetic cells look like?

Spoelstra, W.K. (author), Deshpande, S.R. (author), Dekker, C. (author)

Recently, the bottom-up assembly of a synthetic cell has emerged as a daring novel approach that can be expected to have major impact in generating fundamental insight in the organization and function of actual biological cells, as well as in stimulating a broad range of applications from drug delivery systems to chemical nanofactories. A...

review 2018

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Aerodynamics of transiting objects via large-scale PIV - the Ring of Fire Concept

Spoelstra, Alexander (author)

A novel measurement system, the Ring of Fire, is deployed which enables the aerodynamic drag estimation of transiting cyclists. The system relies upon the use of large-scale stereoscopic PIV and the conservation of momentum within a control volume in a frame of reference moving with the athlete. The rider cycles at a velocity of approximately 8...

master thesis 2017

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Bijlboeg klieft golven

Spoelstra, Jan (author)

journal article 2013