106 research outputs found
The Design Idea of Onno Greiner’s Cultural Center
No full textThe thesis examines the design philosophy of Dutch architect Onno Greiner, with a focus on his work in the Netherlands where he designed three cultural centers: Cultural Center ‘De Tamboer’, Cultural Center Hoogezand, and Cultural Center ‘De Flint’. The topics covered in this article include the relationship between architecture and the city, the flexibility of architecture, and the clarity of architectural space. Through these discussions, not only is Greiner's design philosophy revealed, but also valuable insights are provided for architects to consider in their future work.AR2A011Architectural History ThesisArchitecture, Urbanism and Building Science
Retraction Note: Infection of great apes and a zoo keeper with the same Mycobacterium tuberculosis spoligotype: Infection of great apes and a zoo keeper with the same Mycobacterium tuberculosis spoligotype (Medical Microbiology and Immunology, (2014), 203, 2, (141-144), 10.1007/s00430-013-0323-0)
No full textThe original article has been retracted by the authors because they did not obtain informed consent to publish the description of the case. The content of this article is no longer available online to protect patient confidentiality. Authors Onno W. Akkerman, Tjip S. van der Werf, Adri G. M. van der Zanden, Tony Eger agree to this retraction. Corresponding author, Onno W. Akkerman, stated on behalf of all remaining co-authors that they agree to this retraction
Limit cycles: the elimination of limit cycles iin a CISTR through the application of a feedback process controller
No full textNerium oleander L.
No full text66. Nerium oleander L., Sp. Pl.: 209. 1753 [cited in Nat. Hist. II(4): 389. 1775]. Notes. – A specimen in the Java herbarium is in L (L-898.111-57). It represents material of Plumeria rubra L. (see Nat. Hist. II(2): 178. 1774) (Fig. 2). Two leaves and an inflorescence are mounted with a mid-18th century pot, so far only known from this sheet (G. Thijsse, pers. comm. to the first author). Another specimen without provenance is present in the Thunberg herbarium (UPS-THUNB n° 6128).Published as part of Wijnands, Dirk Onno, Heniger, Johannes, Veldkamp, Jan Frederik, Fumeaux, Nicolas & Callmander, Martin W., 2017, The botanical legacy of Martinus Houttuyn (1720 - 1798) in Geneva, pp. 155-198 in Candollea 72 (1) on page 181, DOI: 10.15553/c2017v721a11, http://zenodo.org/record/572188
Determining groundwater velocity with DTS at the Máximakanaal and in the Horstermeerpolder
No full textA suggested approach for determining groundwater flow in unconsolidated aquifers is tested. Performing a heat pulse response test by using a heat- and fibre-optic cable should result in a vertical profile of groundwater velocities. These cables are installed by using direct push ensuring the direct contact between cable and aquifer. The suggested approach is tested with two case studies. The first case study near the Máximakanaal was meant to determine if the canal is leaking. This experiment failed during the installation which was discovered after analyzing the results. The mistakes that were made during this case study have been analyzed and are discussed. The second case study was not performed by the author of this thesis. Nonetheless, the measurements of this case study enabled the completion of retrieving groundwater velocities from distributed temperature sensing and reviewing the approach
Understanding Solar Cell Contacts Through Simulations
No full textabstract: The maximum theoretical efficiency of a terrestrial non-concentrated silicon solar cell is 29.4%, as obtained from detailed balance analysis. Over 90% of the current silicon photovoltaics market is based on solar cells with diffused junctions (Al-BSF, PERC, PERL, etc.), which are limited in performance by increased non-radiative recombination in the doped regions. This limitation can be overcome through the use of passivating contacts, which prevent recombination at the absorber interfaces while providing the selectivity to efficiently separate the charge carriers generated in the absorber. This thesis aims at developing an understanding of how the material properties of the contact affect device performance through simulations.The partial specific contact resistance framework developed by Onno et al. aims to link material behavior to device performance specifically at open circuit. In this thesis, the framework is expanded to other operating points of a device, leading to a model for calculating the partial contact resistances at any current flow. The error in calculating these resistances is irrelevant to device performance resulting in an error in calculating fill factor from resistances below 0.1% when the fill factors of the cell are above 70%, i.e., for cells with good passivation and selectivity.
Further, silicon heterojunction (SHJ) and tunnel-oxide based solar cells are simulated in 1D finite-difference modeling package AFORS-HET. The effects of material property changes on device performance are investigated using novel contact materials like Al0.8Ga0.2As (hole contact for SHJ) and ITO (electron contact for tunnel-oxide cells). While changing the bandgap and electron affinity of the contact affect the height of the Schottky barrier and hence contact resistivity, increasing the doping of the contact will increase its selectivity. In the case of ITO, the contact needs to have a work function below 4.2 eV to be electron selective, which suggests that other low work function TCOs (like AZO) will be more applicable as alternative dopant-free electron contacts. The AFORS-HET model also shows that buried doped regions arising from boron diffusion in the absorber can damage passivation and decrease the open circuit voltage of the device.Dissertation/ThesisMasters Thesis Materials Science and Engineering 202
Videos of liquid-solid fluidisation experiments of calcite pellets and glass beads in water
No full text20 videos of liquid-solid fluidisation experiments in a university laboratory. You see a 5.7 cm PVC column where tap water is pumped in an upward direction causing particles to elevate into a fluidised state. Particles are calcite grains obtained from a full-scale drinking water softening reactor or perfectly round monodispersed glass beads. The reason to show these videos is to demonstrate that homogeneous flow regime not always occurs whilst this is often assumed regarding liquid-solid fluidisation systems. The viewer can observe open voids of water between the particles and water which choose a path of least resistance through the particle bed. Besides laminar-turbulent regime also homogeneous-heterogeneous distinction is relevant. These observations brought us to revise the standard drag relations used to predict the bed porosity
Queer Encounters in the Archive: Misplaced Love Letters and Autobiographical Homes
No full textThe chapter contains a report of the ongoing research into queer voices and architecture at the Nieuwe Instituut in Rotterdam, which holds the National Collection of Dutch Architecture and Urban Planning. After introducing the National Collection, the authors critically examine how its internal power dynamics and mechanisms privilege certain voices while marginalizing others, followed by a brief overview of earlier ‘queering’ initiatives. In the second part of this chapter, the authors present a selection from the National Collection of three post-war architects who resisted the sexual norms and expectations of their times: Onno Greiner, Dick van Woerkom and Wim den Boon. Their incomplete histories are told through the traces of queer desires and lifestyles which haunt their archives. By discussing their autobiographical house designs, the authors aim to foreground practices of queer worldmaking in the National Collection that let us imagine queer ways of inhabiting, dwelling, and living, while reassessing the history of Dutch modern architecture and some of its tenets related to transparancy, spatial concepts and interior design.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Space & Typ
Equity in traffic light control: Identifying- and measuring equity traffic light control. A case study to improve equity at the intersection A050 in Deventer for intelligent Traffic Light Controller: Flowtack
No full textA new generation of intelligent Traffic Light Controllers uses Model Predictive Control to minimise delay at signalised intersections. The conventional cycle of set sequences of green phases is dropped for optimisation purposes. This research uses the ethical theories utilitarianism, egalitarianism, sufficientarianism & deontology to define equity. An explicit connection of these ethical theories and technical principles of conventional traffic light controller CCOL & new generation traffic light controller Flowtack, has been provided to identify the change in ethical landscape, from predominantly egalitarian towards relatively utilitarian. Performance indicators for equity in traffic control are defined based on earlier research. Multiple setting changes in Flowtack are proposed and tested in simulation experiments with Aimsun. These experiments show that adjusting Flowtack's objective function can improve the equity scores according to egalitarianism & sufficientarianism, at the cost of the equity score of utilitarianism. The best results are validated using various flow compositions on an alternative intersection. As a result, the gain in equity by the proposed settings becomes greater, as the flow composition becomes more uneven. Transport, Infrastructure and Logistic
Fault Tolerant Control and Reliability Assessment of Modular PMSM Drive Systems
No full textThis report proposes an approach to implement improved Fault Tolerant (FT) control in a modular Open Winding (OW) Permanent Magnet Synchronous Machine (PMSM) drive system. The report also proposes a reliability assessment on FT converter topologies and the effect of layering redundancy. An existing lab setup is used as a case study to create a new control system. The redundant case functions with multiple sets of phases, a fault will disable the faulted set leaving the sound phases operational.The new system aims to utilise all remaining sound phases (5 out of 6) in case of an OCF. Operating the drive system in this post-fault condition will leave the system unbalanced, leading to Common Mode (CM) voltage and current. The new system therefore has to operate with the remaining sound phases, whilst reducing the CM disturbance. It is expected that this can be achieved by modifying the control system. Expanding the control system from dq to dq0 allowed control of the zero-sequence current, the CMC.Applying the CMR control allows reduction of CMC in pre- and post-fault condition at nominal load. For post-fault this did result in a current overload of 344.21% in one of the stator phases relative to the pre-fault current. This overload should be taken into account when designing a machine for a specific applications by reducing the post-fault load or over-sizing the machine. The CMR control system proposes an approach to control the machine and reduce the CMC during post-OCF condition. The reliability assessment compared traditional VSI to OW to the extra switching leg converter. Each assessed for one, two and three sets of three phases, also for split and common DC bus. The extraswitching leg and OW topology showed the highest reliability across all phase set configurations. The application of a common DC bus has greatly reduced reliability compared to a split DC bus. The reliability gain of the extra switching leg and OW converter is relatively small compared to the traditional VSI, it is concluded that the traditional VSI is a cost effective converter for achieving FT, if applied redundant
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