35 research outputs found
3D noise simulation: Final report of the 2020 synthesis project
No full textNoise simulations require finding the paths between multiple receiver and source points. In the current approach, only 3D polylines can be used as input to describe the terrain. These 3D polylines are semi-automatically generated, based on the principle of describing the terrain profile with as few height lines as possible. In order to propose a more efficient, standardised and economic modelling approach, a partnership between RIVM/RWS and the 3D Geoinformation Group at TU Delft was launched in 2017, aiming to generate these height lines automatically from the available datasets, namely AHN3, BAG, and BGT, which are publicly available via PDOK for free. However, it was then proposed to prove that the paths between receiver and source points can be directly generated from a TIN without creating the height lines. The following report provides proof of concept to the hypothesis: ‘Using a TIN directly allows automated 3D noise modelling according to the guidelines of CNOSSOS-EU’. A code was written to generate the paths between receiver and source points using an LoD2 TIN. The paths were then checked visually and were fed to test_Cnossos software to prove their validity. Finally, noise maps were generated and compared to noise maps generated with the current method.3D noiseGeomatic
Return to sender: Constantijn Huygens as a man of letters
No full textReturn to Sender takes as its starting point Constantijn Huygens’ letters and shows us the author in his different guises: intimus of René Descartes, translator of John Donne, collector of art, writer of flirtatious love letters and the author of a long consolatory letter-poem for an ailing friend who threatened to go blind. In his letters, Huygens emerges as an often playful yet always ambitious fashioner of his own social image. Return to Sender gives us Huygens as ‘a man of letters’ in a very literal way: conceiving and construing his texts with an addressee in mind, but also with the distinct intention to fashion for that reader a persona that could be represented by means of the text at hand
Soeticheydt des Buyten-levens: Leven en leren op Hofwijck
No full textDe geschriften van Constantijn Huygens hebben veel van het leven in de zeventiende eeuw weten te verduidelijken. Huygens' belangstelling was veelzijdig, zijn visie en inzicht breed en diep tegelijk . In Leven en leren op Hofwijck staan opvoeding, onderwijs en het familieleven van Huygens en zijn kinderen centraal. Dankzij de bijdragen van een zevental Huygens-specialisten maakt de lezer kennis met een aantal alledaagse aspecten van deze onalledaagse zeventiende eeuwse familie
Local multi-qubit Clifford equivalence of graph states
No full textIn the range of applications opened by quantum technology, often a highly entangled source state is needed as an input for a protocol (target state). The easiest example of such an application is QKD, other examples are quantum secret sharing and measurement based quantum computing. Generating a non-local entangled state is however not trivial. Let us assume that there is an entangled state (source state) present in the network before the start of the protocol. One can ask than whether this source state can be transformed to the target state with only local operations. Local operations usually have a lower error rate compared to non-local operations. As the set of all quantum states increases exponentially, we will restrict ourselves to graph states (quantum states described by a simple graph). This allows one to study the graphs and local operations in a graph theory perspective, instead of in a quantum information perspective. In this thesis we investigate the complexity of deciding equivalence of two graph states under local multi-qubit operations (T-LMQC-equivalent), where T refers to the partition denoting which qubits are on the same device which allows multi-qubit operations.When T consist only of single qubit nodes, this problem reduces to the single qubit Clifford equivalence problem (SQC-EQUIV). It is known that SQC-EQUIV can be solved in O(N^4). On the other side, if all qubits are in the same node, the problem can be solved in O(1) as every source state can be transformed to any graph state on the same vertex set. We will present three algorithms to solve T-LMQC equivalence. The first algorithm solves the problem in general but the running time scales exponentially in the number of multi-qubit nodes and the size of the graph. The other two scale polynomially in the size of the graph, but do not allow for nodes with more than 2 qubits. The remaining question is indeed whether deciding T-LMQC equivalence is an easy (in P) problem or a hard problem (NP-complete).Applied Physics | Quantum Technolog
Allemaal Gelogen: Feit en fictie in Bougainville (1981) van F. Springer
No full textIn this article I briefly introduce the Dutch diplomat and author Carel Jan Schneider (Batavia 1932-Den Haag 2011) and his literary work. Under his pseudonym F. Springer he published fourteen books: novels and short stories. His work has been translated into French, German, Thai, Danish, Bulgarian, Slovak and Japanese. In 1995 Springer was awarded the prestigious Constantijn Huygens Prize for his complete works of fiction.
In my article I will touch upon the following questions: did Schneider’s profession as a diplomat influence his way of writing and to what extent are fact and fiction interwoven in his work?In this article I briefly introduce the Dutch diplomat and author Carel Jan Schneider (Batavia 1932-Den Haag 2011) and his literary work. Under his pseudonym F. Springer he published fourteen books: novels and short stories. His work has been translated into French, German, Thai, Danish, Bulgarian, Slovak and Japanese. In 1995 Springer was awarded the prestigious Constantijn Huygens Prize for his complete works of fiction.
In my article I will touch upon the following questions: did Schneider’s profession as a diplomat influence his way of writing and to what extent are fact and fiction interwoven in his work?In this article I briefly introduce the Dutch diplomat and author Carel Jan Schneider (Batavia 1932-Den Haag 2011) and his literary work. Under his pseudonym F. Springer he published fourteen books: novels and short stories. His work has been translated into French, German, Thai, Danish, Bulgarian, Slovak and Japanese. In 1995 Springer was awarded the prestigious Constantijn Huygens Prize for his complete works of fiction.
In my article I will touch upon the following questions: did Schneider’s profession as a diplomat influence his way of writing and to what extent are fact and fiction interwoven in his work
Portfolio-based airline fleet planning under stochastic demand
No full textAirlines operate their fleet of aircraft over a relatively long time horizon during which the realized stochastic demand has the potential to profoundly impact the airlines’ financial performance. This makes the investment in a fleet of aircraft a highly capital-intensive long-term commitment, associated with inherent risks. We propose an innovative three-step airline fleet planning methodology with the primary objective of identifying fleets that are robust to stochastic demand realizations. The methodology presents two main innovation aspects. The first one is the use of the mean reverting Ornstein–Uhlenbeck process to model the long-term travel demand, which is then combined with discrete-time Markov chain transitions to generate demand scenarios. The second innovative aspect is the adoption of a portfolio-based fleet planning perspective that allows for an explicit comparison of different fleets, in size and composition. Ultimately, the methodology yields for each fleet in the portfolio a distribution of net present values of operating profit across the planning horizon and a list of key financial and operational metrics per year. The robustest fleet can be selected based on the operating profit generating capability across different realizations of stochastic demand. An illustrative case study is presented as a proof of concept. The case study is used to demonstrate the type of results obtained and to discuss the usefulness of the methodology proposed.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.Air Transport & Operation
eVTOL Design, Energy Storage & Charging
No full textAs electric vehicles are quickly taking over the automotive industry, electric airplanes are also starting their upswing. With air travel and transport in general being a large polluter of CO2 gases, the transition to electric flight becomes more prominent every year. This transition is starting small with non-commercial airplanes. Several companies are starting with development of eVTOLs, electric Vertical Take-Off and Landing vehicles. The idea behind them is that they can easily move into and out of the city through the air, speeding up transport and travel in urban areas while keeping CO2 emissions at the vehicle level at zero.This thesis, together with two other theses, will elaborate on the design of such an eVTOL. Its design is created by looking at the layout of the propellers, the wings and the fuselage and the internal layout is composed by working out the electric drivetrain from the energy storage to the electric motors and by drafting up the control systems. In specific, this thesis dives into the external design and the internal electric energy storage. It does this by settling on a design and calculating certain specifications, like wing area and propeller and fuselage size. From there the necessary powers and energies are calculated. With these powers and energies, a battery pack is designed together with a battery management system and a charging system. The other two theses will design the propulsion system and the control system of the eVTOL.The result of the thesis is a theoretical design that states the possibilities of Lithium-Sulfur cells inside an eVTOL. An efficient tandem wing design with fixed wings and fixed rotors makes sure there is a healthy balance between the maximum power and total energy needed to take off vertically and fly 125 kilometers. With the Lithium-Sulfur cells a battery pack is made with its accompanying battery management system that monitors and manages the cells' characteristics. Next to the battery pack, theory on charging and a simplified charging simulation has been done to show that charging in 15 minutes should be possible by the time the eVTOL enters into service
Annuities and Retirement Satisfaction
No full textThis paper analyzes pre-retirement expectations and post-retirement satisfaction, in particular their association with the degree to which retirees' financial resources are in the form of annuities. Using the 1992-2000 Health and Retirement Study (HRS), the author finds that most retirees are very satisfied with their overall situation, but the degree of satisfaction varies substantially with retirees' characteristics. In particular, people in better health and with more financial resources tend to be more satisfied. Holding constant the present value of retirement resources and other factors, the author finds that retirees who can finance more of their consumption in retirement from pension annuities (vs. Social Security benefits and accumulated savings) are more satisfied. Retires with lifelong annuities also tend to maintain their level of satisfaction during retirement, whereas those without tend to become less satisfied over time. The author finds the very same patterns with alternative depression-related measures of well-being in retirement. The findings have important implications for the well-being of future American retirees, who are increasingly reliant on DC pension plans rather than the traditional DB pensions.
The anuran skin peptide bradykinin mediates its own absorption across epithelial barriers of the digestive tract
No full textWhen faced with a potential predator, a wide range of frog species secrete a mixture of peptide toxins from their skin to defend themselves. We have recently shown that antimicrobial peptides (AMPs) in a frog's defensive poison enhance the uptake of these peptides across epithelia, thereby speeding up the process of predator intoxication. This study provides evidence that bradykinin, a widespread peptide toxin in anurans (frogs), is capable to pass through epithelial barriers independent of this delivery system. We quantified bradykinin peptides secreted by Bombina orientalis during acute stress, and found that at biologically relevant concentrations, bradykinin passage across model epithelia occurs even in the absence of AMPs. Monitoring of transepithelial electric resistance showed that bradykinin treatment caused a subtle yet prolonged reduction in barrier function, indicating that the peptide itself is capable to increase the permeability of epithelia. Yet, bradykinin does not cause cells to leak lactate dehydrogenase, suggesting that it does not damage cell membranes. Moreover, imaging of bradykinin-treated monolayers shows no endocytosis of fluorescent propidium iodide, indicating that the peptide does not perforate cell membranes at smaller scale and therefore is unlikely to cross epithelia via a transcellular passage. Together, these observations suggest that bradykinin, unlike other amphibian neuropeptide toxins, mediates its own passage across mucosal barriers, possibly through a paracellular route. This "self-administering" property, combined with the fact that bradykinins can potently disturb multiple physiological processes, could explain why these peptides are one of the most widespread antipredator peptides in the defensive secretions of frogs
Esclaircissement sur deux maîtres plurilingues du XVIIe siècle à Leyde
Get PDFEn 1655 paraît l’Esclaircissement de quelque differents en la langue Italienne, livre de 80 pages de la main de Nathanael Duez, auteur à succès d’ouvrages didactiques du français, de l’italien et de l’allemand. Ce texte fournit une réponse à quelques remarques linguistiques formulées à l’encontre de Duez par Pietro Paravicino, maître plurilingue, resté dans l’ombre jusqu’à présent, et ami du célèbre poète Constantijn Huygens. Bien que la dispute ait déjà été évoquée à plusieurs reprises dans la littérature, elle n’a jamais fait l’objet d’une étude poussée. Or, cette querelle révèle des informations intéressantes, non seulement sur la langue italienne, mais aussi sur les conceptions didactiques de ces deux maîtres de langues du XVIIe siècle.In 1655 theEsclaircissement de quelque differents en la langue Italienne appeared, a book consisting of 80 pages by Nathanael Duez, a successful author of methodological works of French, Italian and German. The volume is an answer to some negative linguistic comments Duez received from Pietro Paravicino. The latter was a multilingual language teacher, who has remained unnoticed up to now, and a friend of the famous Dutch poet Constantijn Huygens. Even though this dispute has been mentioned several times in the literature, it has never been fully studied. Still, the quarrel provides interesting information, not only about the Italian language, but also with regard to the methodological ideas of these two language teachers of the XVIIth century
