80 research outputs found
Joint Estimation of Hemodynamic Response and Stimulus Function in Functional Ultrasound Using Convolutive Mixtures
No full textFunctional ultrasound (fUS) is an exciting new neuroimaging technique that is able to record brain activity similar to functional magnetic resonance imaging, yet with higher spatiotemporal resolution and at lower cost. We consider the problem of jointly estimating the underlying neural sources and the hemodynamic response function (HRF) from fUS recordings. We propose to model the measured voxel time-series as a convolutive mixture of multiple source signals and solve the blind deconvolution problem via block-term decomposition. This allows us to estimate both the source time courses and a different HRF for each voxel and source combination, which accounts for the variability of HRF across different brain regions and events respectively. The proposed approach is proven to be robust against noise via simulations and further validated on real fUS data by performing a visual experiment on a mouse. The obtained results show that the proposed method is able to recover the timings of the visual paradigm.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.Signal Processing System
Esopus in Europa.
No full textGedrukt na de Romeinsche copyAlgemene titel voor een verzameling van veertig weekblaadjes door Romein de Hooghe, elk met een titelprent en gepagineerd 1-8. De twintig laatste dragen het jaartal 1702.Onvolledig exemplaar: titelstuk, 4-5e en 40e stuk ontbrekenVerpakt met de steun van Fonds Inbev-Latour (2010-2012)[2] De toverlantaaren. -- [3] De bezwoorene schim. -- [4] Hansop op de koord. -- [5] Hikhakken van den tel. -- [6] Het geschil, tussen de Fransche haan, en Lombaardsche hennen ...[7] Twist tusschen de Spaansche ginet, en Fransche mazet [...] -- [8] Italiaansche vos in het geallieerde tuighuis. -- [9] Rouwklagt van de Fransche Apollo over de verdorde distelbloem. -- [10] Saamenspraak tusschen Marforio en Jacquet du Moulin[11] Grafschrift door Marforio over een der vaders van Jacquet Bandyt. -- [12] Byeenkomst der moogendheden in het hof van den leeuw. -- [13] De tyger voor Themis vierschaar. -- [14] Saamenspraak tusschen de wichelstok, smeltkroes, en de monsterrol[15] Saamenspraak tusschen het valies, de myter, en het bonnet. -- [16] Maatroozen saamenspraak te Port a Port, benevens de fabel van de kakatoe, kuykedief, en den haan. -- [17] De Napelsche hengst, visscher, en pikeur. -- [18] De Ongerse Pallasch, de boere Caraffa, en hoerensmeerdoos. -- [19] De Fransche degen, de sleutel, en het bonnet tot Luyk[20] Ptolomeus, Copernicus, en Merkuur op de Parnas over de zon en de waereld. -- [21] De leuterbol van Diest, de hond, en de pikbroek, by den laatste stuyver. -- [22] De Italiaansche waarzegger. Esopus, Antonio Magino, en Dirk Rembrantz van Nierop. -- [23] Het heydinnetje, de Miquelet, en Mooyfraaykiek, in de Pirenëen. -- [24] Opera van Andromache te Milaanen[25] De horlende kollendans, op Tilburn. -- [26] De jonge koekkoek onder de kraanvogels. -- [27] Nebucadnezars beeld tot Versailles ten toon gesteld, om tot Madrid opgerigt te worden. -- [28] De hobbel in de wacht, op de haasejagt. -- [29] Europe nooit voor een[30] Gedwonge mars, gaat altyd dwars. -- [31] Het Cremoneesche vreugdevuur. -- [32] De Spaansche carravaan. -- [33] De geschooren hoop. -- [34] Europa in rouw. -- [35] De waarheid boven al.[36] De gefopte bedrieger. -- [37] De ontdekte eenhoorn. -- [38] De groote Christoffel. -- [39] De misleide poesjes. -- [40] De geplukte Tapoeijer.Herkomst: Vignet Isaac MeulmanVan der Wulp, J. K. Tractaten, pamfletten enz. 7211Europeana-GoogleBook
Gravity Base Foundations for Offshore Wind Turbines
No full textThe scope of this study is to investigate the possibilities for applying Gravity Base Foundations at larger water depths. To do so the influence of various parameters for the foundation and turbine are investigated as well as the properties of the sub soil. It is concluded that it is technically possible to construct concrete Gravity Base Foundations for larger water depths, but due to the increase of the foundation weight the handling of the foundations and the bearing capacity of the sub soil are the aspects that are determining the applicability to a large extend.Structural and Building Engineering, Concrete StructuresStructural EngineeringCivil Engineering and Geoscience
Appartementje, boompje, beestje: An architectural building experiment in social housing to accommodate families with young children in the inner city
No full textThis graduation project focuses on how architecture and the built environment can provide a child-friendly and future-proof childhood in the inner city. In the Netherlands we have got the phrase huisje, boompje, beestje. This symbolizes the phase of young couples who are going to settle and are having a nice, quiet and standard family life. For many of those the social succes image includes a single-family home with a garden. Apartment living is widely seen as inappropriate for children and therefore they think that this is the best place to have their huisje, boompje, beestje. This project will show that this can be done differently and can change into a new culture: appartementje, boompje, beestje
ROBAT: Experimental investigation of a bat inspired robotic wing
No full textThe research done on bat flight has increased the knowledge about bat flight and the corresponding aerodynamic phenomena in great extent. In the mid seventies and eighties, the first kinematic studies by Norberg (1976a,b) and Aldridge (1986, 1987) were performed with the use of high speed cameras and made it possible to analyze the kinematics of bat flight in great detail. These studies were first performed in _ight corridors, later followed by measurements in windtunnels (Busse von, 2011). This made it possible to measure over a range of flight speeds, which shows a gradual change in kinematics when _ight speed is increased. Aerodynamic measurements were the next step in bat flight research and gave a better insight in the vortex structure of bat _ight both onwing (Muijres et al., 2008) and in the wake (Hedenstrom et al., 2007, 2009; Johansson et al., 2008).Aerospace Engineerin
An Ammonia-Fuelled Solid Oxide Fuel Cell - Internal Combustion Engine Hybrid System for Ships
No full textAmmonia (NH3) may reduce CO2 emissions from the marine industry as it is carbon-free and more energy-dense than hydrogen or batteries. Pure ammonia exhibits poor combustion characteristics, so several researchers have already operated small-scale internal combustion engines (ICEs) with ammonia-hydrogen blends. However, nitrogen oxides NOx and unburned ammonia are major objections that require the after-treatment of exhaust gases. Experimental studies with solid oxide fuel cell (SOFC) stacks up to 1 kW demonstrated that SOFCs can convert ammonia to electricity with the highly endothermic ammonia cracking reaction at the fuel electrode or before the SOFC as an intermediate step. Although SOFCs tend to be more efficient and emit fewer NOx compared to ICEs, their power density, dynamic behaviour and investment costs are inferior. Different authors came up with integrations of mostly methane-fuelled SOFCs with gas turbines or internal combustion engines. This work presents an ammonia-fuelled SOFC--ICE hybrid system in which hydrogen off-gas from an SOFC enhances ammonia combustion in an ICE. 0-D components models are developed in an integrated model to quantify the effect of different parameters on fuel efficiency, power density, and heat management. The hybrid system simulations vary three parameters, all in three different ways. First, the SOFC provides either 25, 50 or 75% of the hybrid system power, resulting 25/75, 50/50 or 75/25 SOFC/ICE power splits. Secondly, either 0, 50 or 100% of the hydrogen in the SOFC is obtained from external cracking before the stack. Thirdly, the share of hydrogen in the ammonia-hydrogen ICE fuel blends is varied: 20, 30 and 40%. This leads to 27 distinct simulations, all at 5000 A/m2 SOFC current density. Besides, current density is varied from 2500 and 5000 to 9000 A/m2 in the 50/50 SOFC/ICE power split configuration. Full internal cracking of ammonia in the SOFC results in an electrical efficiency of up to 58% and 54% (based on the lower heating value) for a 75/25 and 50/50 power split, respectively, but it leads to heat management failures in the 25/75 power split; where 50% external cracking results in 47% efficiency. Complete external instead of internal cracking decreases efficiency by at most 10 percent points (75/25 power split), because additional fuel is needed heat to the external cracker. Moreover, external cracking results in increased power consumption by the cathode air blower. The ICE efficiency, 41% (standalone system) or 43% (being part of the hybrid system), is outperformed in all 27 simulations mentioned above. The after-treatment model predicts the formation of highly unwanted N2O. The computed SOFC--ICE specific volume is 2, 3 or 4 times larger than an ICE, but less fuel tank space required could cancel this out. This research indicates that an SOFC reduces fuel consumption compared to an ICE, but using hydrogen off-gas with ammonia in an ICE is advantageous for power density and efficiency. Furthermore, operational parameters of the SOFC can be adjusted in favour of the system efficiency until there is too little electrochemical waste heat compared to the heat absorbed by ammonia cracking in the SOFC. Amongst many other topics, future research should include part load and dynamic operation because of the expected benefits of the hybrid system. AmmoniaDriveMechanical Engineering | Energy, Flow and Process Technolog
Capacity of prestressed concrete bridge decks under fatigue loading
No full textIn The Netherlands, existing slab-between-girder bridges with prestressed girders and thin transversely prestressed concrete decks require assessment. The punching capacity was studied in a previous series of experiments, showing a higher capacity thanks to compressive membrane action in the deck. Then, concerns were raised with regard to fatigue loading. To address this, two series of large-scale experiments were carried out, varying the number of loads (single wheel print versus double wheel print), the loading sequence (constant amplitude versus variable amplitude, and different loading sequences for variable amplitude), and the distance between the prestressing ducts. An S-N curve is developed for the assessment of slab-between-girder bridges. The experiments showed that compressive membrane actions enhances the capacity of thin transversely prestressed decks subjected to fatigue loading.Accepted Author ManuscriptConcrete Structure
Example of Proof Load Testing from Europe
No full textThis chapter describes the proof load testing of viaduct Zijlweg at a position that is critical for bending moment and at a position that is critical for shear. The viaduct Zijlweg has cracking caused by alkali-silica reaction, and the effect of material degradation on the capacity is uncertain. Therefore, the assessment of this viaduct was carried out with a proof load test. This chapter details the preparation, execution, and evaluation of viaduct Zijlweg. The outcome of the proof load test is, according to the currently used methods for proof load testing, that the viaduct fulfills the code requirements, and that strengthening or posting is not required.Accepted Author ManuscriptConcrete Structure
Measurement Report on the Transition between Flexural and Shear Failure on RC Beams without Shear Reinforcement
No full textThis is a measurement report of the test series on reinforced concrete beams without shear reinforced carried out in Delft University of Technology from April 08, 2015 till July 01, 2016. The target of the research is to investigate the transition of shear failure and bending failure. In this report, the detailed information of the experimental program is given. In addition to that, the main results of each experiment, including the description of each test, a selection of the measurement results are summarised. This report is used as an accompany to support the conclusions and the analysis of the report on the determination of the minimum shear strength before flexural failure, and other researches related to this shear – bending test series.Concrete Structure
Fatigue Testing of Transversely Prestressed Concrete Decks
No full textIn the Netherlands, slab-between-girder bridges with prestressed girders and transversely prestressed decks in between the girders require assessment. Static testing showed that compressive membrane action increases the capacity of these structures and that the decks fail in punching shear. The next question is if compressive membrane action also increases the capacity of these decks under repeated loads. Therefore, the same half-scale bridge structure as used for the static tests was subjected to repeated loads at different fractions of the maximum static load, different loading sequences, and for single and double concentrated loads. A relationship between the load level and number of cycles at failure (S-N curve) for the assessment of these bridges is proposed, but the influence of the loading sequence was not successfully quantified yet. The conclusion of the experiments is that compressive membrane action enhances the punching capacity of transversely prestressed thin decks subjected to repeated loads.Accepted Author ManuscriptConcrete Structure
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