775 research outputs found
Rip Current Prediction System for Swimmer Safety: Towards operational forecasting using a process based model and nearshore bathymetry from video
No full textRip currents are among the most dangerous coastal hazards for the bathing public, and contribute to the highest portion of beach rescues all over the world. In order to help life guards in planning and preparing rescue resources so as to minimize casualties, information about where and when rip currents may occur is needed. This can be provided by a predictive tool which combines meteorological forecasts, hydrodynamic models and remote-sensed observations. In this thesis, a methodology with which rip current forecasts for swimmer safety can be provided is developed and tested for Egmond aan Zee beach in the Netherlands. The approach is to make use of the numerical model system CoSMoS combined with daily estimates of nearshore-scale bathymetry obtained from a system called cBathy, which infers depths by estimating wave celerities from video imaging. Moreover, in order to gain more knowledge on occurrences of rips at Egmond, a numerical study on the kinematics of rip currents and the safety implications for swimmers is also presented. Coupling the video bathymetry estimates with CoSMoS in forecast mode shows that dangerous rips were correctly predicted. This thesis demonstrates the potential application of the proposed system in providing forecasts for rip currents at Egmond aan Zee.Hydraulic EngineeringCivil Engineering and Geoscience
Representing silk design: Nicholas Joubert de L'Hiberderie and Le dessinateur pour les etoffes d'or, d'argent et de soie (Paris, 1765)
No full textLe Dessinateur pour les étoffes d'or, d'argent et de soie was published in Paris in 1765 depite the reservations of the silk-weaving guild of Lyons, receiving a good response in the Enlightenment press. As the first description on French of the trade of silk designer to appear in the public domain, it has become an important work on which much subsequent history has been based, often rather uncritically. This article delves into the representation of design offered by this text, evaluating it against the personal experience of its author, the literary and manufacturing heritage on which he drew, and the readership for women it was intended. The analysis is based on the form and content of the book, the structure, vocabulary and illustrations. Comparative data are drawn from two other important publications on silk manufacture, the relevant sections of Denis Diderot's Encyclopédie and Jean Paulet's L'Art du fabriquant
Marketing communications plan for L.E. Jones company Menominee, Michigan
No full textThe author researched the feasibility of improving marketing communications for L.E. Jones Company of Menominee, Michigan. Based on career experience and scholarship gained through the Cardinal Stritch Master of Business Administration program, the author was able to identify the problems facing the firm, analyze the marketing communications needs, recommend various alternatives, assist in the selection of alternatives, and create the actual advertising and sales support materials. These improvements in marketing communications will permit the firm to more confidently pursue new business in an increasingly competitive market
Application of Beach Wizard for coastal operational model system
No full textA preliminary operational model system for the Dutch coastline has already initiated by Deltares under the MICORE and Delft Cluster projects. This MSc thesis presents performance of the models within the system. A validation is carried out to the Continental Shelf Model (SWAN for the wave model and Delft3D FLOW for the hydrodynamic model) of the operational model system with simulation length of one month. Two period of simulations are considered for the validation. For the first period, the whole month of June 2009 is considerd , while for the second period the simulation lenght will be from 25 October 25 November 2009. These two period of simulation represent two different climate characteristics, summer/non storm situation represented by the first period (June), while storm condition will be represented by the second period (October-November). The result shows that the model system presents a good skill in reproducing hydrodynamic parameters such as wave heights and water levels. However, the wave model shows different skill with different period of simulation. The wave model performs relatively better during storm period of simulation compare to summer period. In addition, it is also found that, the wave model underestimates the wave height when swell exist. Beach Wizard, as introduced by van Dongeren et al., 2008, provides a tool which is capable to estimate sub-and intertidal bathymetry, based on difference between (computer) model computation and remote sensed observation (video technique). A test case is carried out for Egmond Beach, in the Netherlands, in order to evaluate the performance of Beach Wizard scheme, using a short span of data, during calm/summer period. Some problems are identified, which further will become very useful information, in order to improve the whole system (Argus system as remote sensed data generator, and Beach Wizard as the model engine itself), and further to integrate the Coastal Operational Model System with the Beach Wizard
Rip current prediction system for swimmer safety : towards operational forecasting using a process based model and nearshore bathymetry from video; Dissertation, UNESCO-IHE Institute for Water Education, Delft and Delft University of Technology.
No full textRip currents are among the most dangerous coastal hazards for the bathing public, and contribute to the highest portion of beach rescues all over the world. In order to help life guards in planning and preparing rescue resources so as to minimize casualties, information about where and when rip currents may occur is needed. This can be provided by a predictive tool which combines meteorological forecasts, hydrodynamic models and remote-sensed observations. In this thesis, a methodology with which rip current forecasts for swimmer safety can be provided is developed and tested for Egmond aan Zee beach in the Netherlands. The approach is to make use of the numerical model system CoSMoS combined with daily estimates of nearshore-scale bathymetry obtained from a system called cBathy, which infers depths by estimating wave celerities from video imaging. Moreover, in order to gain more knowledge on occurrences of rips at Egmond, a numerical study on the kinematics of rip currents and the safety implications for swimmers is also presented. Coupling the video bathymetry estimates with CoSMoS in forecast mode shows that dangerous rips were correctly predicted. This thesis demonstrates the potential application of the proposed system in providing forecasts for rip currents at Egmond aan Zee
On Sense, Tone, and Accompanying Thoughts
No full textThe paper deals with Frege's distinction between sense and colouring or tone as applied both to proper names and to compound sentences. It argues that Frege's way of drawing this distinction is unsatisfactory, much for the same reasons as Grice's theory of conventional implicature is a non starter. The author suggests that tone may contributes to assertoric content depending on contextually specified circumstances. The phenomenon of linguistic underdetermination is very widespread, and tone is only the tip of an iceberg that we need to explore more fully.
The paper deals with Frege's notions of sense and tone within the framework of recent theories of contextualism, literalism and multi-dimensionalism. Dummett's account of Frege's account of sense is reviewed and extended. The author suggests that tone differs from sense only as regards a higher degree of undeterdeterminationa and occasion sensitivity. Tone contributes to assertoric content, and differs from conventional implicatures, as described by Paul Grice and his followers
Wiring the Binocular Visual Pathways
No full textAuthor Contributions: Conceptualization, V.M.-B. and L.E.; writing—original draft preparation, V.M.-B. and L.E.; writing—review and editing, V.M.-B. and L.E.; visualization, V.M.-B. Funding: V.M.-B. holds a postdoctoral contract from the Generalitat Valenciana (APOSTD/2016/017).Peer reviewe
Optimizing stakes in simultaneous bets
No full textWe want to find the convex combination S of iid Bernoulli random variables that maximizes P(S ≥ t) for a given threshold t. Endre Csóka conjectured that such an S is an average if t ≥ p, where p is the success probability of the Bernoulli random variables. We prove this conjecture for a range of p and tGreen 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.Applied Probabilit
Met Markov ketens op zoek naar de Zero Variance Importance Sampling verdeling
No full textStandaard Monte Carlo is niet geschikt voor het analyseren van Rare Events. We laten zien dat we bij dit soort problemen Importance Sampling kunnen toepassen en hoe we de Zero Variance verdeling kunnen vinden. Deze verdeling hangt echter af van constanten waar we de waarde niet van weten, maar door deze constanten te benaderen krijgen we een benadering van de verdeling. We passen deze methode toe op een eenvoudig (bonimiaal) Credit Risk model. Door de Zero Variance verdeling beter te benaderen, kunnen we een grotere variantie reductie realiseren. We hebben daarom een nieuwe methode ontwikkeld die na elke iteratie een betere benadering van deze verdeling geeft. De variantie reductie bij het gebruik van deze methode is aanzienlijk maar de methode is niet eenvoudig te implementeren.Applied MathematicsDelft Institute of Applied MathematicsElectrical Engineering, Mathematics and Computer Scienc
Maximally Adaptive Nonparametric Importance Sampling
No full textNowadays, Monte Carlo integration is a popular tool for estimating high-dimensional, complex integrals. Its scope of application can be widened if ways can be found to produce estimates with smaller variance at the same computational cost. Variance reduction techniques aim to accomplish this. In particular, using importance sampling with the so-called zero-variance distribution would result in a simulation procedure with variance zero. Unfortunately the zero-variance distribution cannot be constructed in practice, as it requires knowledge of the value to be estimated. In this thesis we look at how iterative approximation of the zero-variance distribution can be exploited to yield more efficient Monte Carlo simulations, a technique called adaptive importance sampling. We will explore the characteristics of existing methods for adaptive importance sampling, and prove some generic limit theorems for such methods. Based on the methods by Ping Zhang, which use kernel density estimation to approximate the zero-variance distribution, we then propose Maximally Adaptive Nonparametric Importance Sampling. This variation aims to make better use of the information available by updating its approximation to the zero-variance distribution after every generated sample. We will show that the method (when using n samples) yields an estimator with an asymptotic variance of O(ln(n)n^{-7/6}), faster than methods (eventually) based on i.i.d. replicates. We illustrate the empirical convergence of the method with a simulation experiment, and briefly discuss the issues and considerations related to application of the method in practice.ProbabilityApplied mathematicsElectrical Engineering, Mathematics and Computer Scienc
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