1,388,391 research outputs found
VISSER, Isabella Gordon [Tibbie] Inventory of documents
No full textCOVERAGE 1875-1975; 135 Files; 3,22 Metres.
AUDIO CASSETTES IN ARCA COLLECTION = 4Private papers of I.G. Visser, daughter of President M.T. Steyn. In 1916 she married Rev. N.J. van der Merwe MP Winburg [1924-1940]. After his death she married Dr. C.F. Visser [in 1943] who was a founder member of the Voortrekkerbeweging. I.G. Visser was MPC [1954-1960], Senator [1960-1974]
Eelco Visser - An Exceptional SLE Researcher
Get PDFThese notes honor Eelco Visser as an exceptional member of the Software Language Engineering (SLE) community. The notes are authored from the perspective of an SLE co-founder and a continuous SLE supporter. As an inevitable side effect, a short history of SLE is captured. The commemoration begins with Eelco’s role in launching the SLE conference. The commemoration continues with Eelco’s contributions as an author and his involvement with running the conference and working towards an SLE Body of Knowledge (SLEBoK). The commemoration ends with recalling Eelco’s role as the de-facto SLE photographer
From Trash to Cash
No full textDatasets for paper: De Visser-Amundson, A., Kleijnen, M., & Aydinli, A. (2023). From Trash to Cash: the effect of product construal and benefit appeals on consumer evaluations of rescued meals. International Journal of Contemporary Hospitality Management, 35(12), 4365-4383
Conf Researchr: A Domain-Specific Content Management System for Managing Large Conference Websites
Get PDFConferences are great opportunities for sharing research, debating solutions, and networking. For the organizing committee there is a considerable deal of complexity and effort required to provide attendees and organizers with ways to find and manage programs, sessions, papers, tracks, talks, and authors. Eelco Visser found an opportunity to provide an integrated solution to these problems by designing the Conf Researchr conference management system in 2014 using our own domain-specific web programming language WebDSL. In this paper, we highlight the impact Eelco had on conference management, and how Conf Researchr evolved to become the platform of choice for hosting over 900 conference and workshop editions in SIGPLAN and SIGSOFT, among other areas of computer science research
Recommended from our members
Death and the Screen [Special Issue]
No full textThis wholly open access special issue of Revenant: Critical and Creative Studies of the Supernatural, guest edited with colleague Dr Renske Visser, includes interdisciplinary critical and creative submissions on myriad intersections between death and the screen. Revenant is a peer-reviewed e-journal dedicated to academic and creative explorations of the Supernatural, the Uncanny and the Weird. ISSN 2397-8791
Eelco Visser and IFIP WG 2.16
Get PDFEelco Visser was a founding member of the IFIP TC2 Working Group 2.16 and long served as its chair. This brief note recounts Eelco’s impact on the group and his contributions to its meetings
Sur l'inégalité de Visser
Get PDFSoit p un polynôme d'une variable complexe z. On peut trouver plusieurs inégalités reliant le module maximum de p et une combinaison de ses coefficients. Dans ce mémoire, nous étudierons principalement les preuves connues de l'inégalité de Visser. Nous montrerons aussi quelques généralisations de cette inégalité. Finalement, nous obtiendrons quelques applications de l'inégalité de Visser à l'inégalité de Chebyshev.Let p be a polynomial in the variable z. There exist several inequalities between the coefficents of p and its maximum modulus. In this work, we shall mainly study known proofs of the Visser inquality together with some extensions. We shall finally apply the inequality of Visser to obtain extensions of the Chebyshev inequality
Sur l'inégalité de Visser
Get PDFSoit p un polynôme d'une variable complexe z. On peut trouver plusieurs inégalités reliant le module maximum de p et une combinaison de ses coefficients. Dans ce mémoire, nous étudierons principalement les preuves connues de l'inégalité de Visser. Nous montrerons aussi quelques généralisations de cette inégalité. Finalement, nous obtiendrons quelques applications de l'inégalité de Visser à l'inégalité de Chebyshev.Let p be a polynomial in the variable z. There exist several inequalities between the coefficents of p and its maximum modulus. In this work, we shall mainly study known proofs of the Visser inquality together with some extensions. We shall finally apply the inequality of Visser to obtain extensions of the Chebyshev inequality
A model for breach growth in a sand-dike and its prediction for the Zwin 94 experiment
No full textA mathematical model for breach growth in sand-dikes and dunes is described. The model is based on the five-step breach erosion process as observed in several laboratory experiments and the Zwin 89 field experiment. A simplified Galappatti (1983) pick up mechanism for sand from the bed is combined with Bagnold's (1963) modified (Visser, 1988) energetics-based sand transport conception to describe the breach erosion. The test of the model to the data of the Zwin 89 experiment shows good agreement. Finally, a prediction for the growth of the breach width in the Zwin 94 experiment is given.Hydraulic EngineeringCivil Engineering and Geoscience
Application of sediment transport formulae to sand-dike breach erosion
No full textThe Technical Advisory Committee on Water Defences in the Netherlands has decided to develop a mathematical model for breach erosion in dunes and dikes, with which it will be possible to predict the growth of the breach and the discharge rate through the breach in case of a dike-burst. An essential part of such a mathematical model is the description of the entrainment of the sediment (sand or clay) and its transport through the breach. The process of breach erosion, especially in the first phases, is characterized by relatively steep slopes and large flow velocities. None of the existing sediment transport formulae has been derived and tested for these circumstances. This report presents the results of an investigation into the applicability of sediment transport formulae to sand-dike breach erosion. In view of the steep slopes and the large flow velocities, the following sediment transport conceptions have been included in the study: formulae for sand-water mixture flows: Wilson (1966), Wilson (1987), Mastbergen and Winterwerp (1987); formulae for sediment transport in flows on relatively steep slopes: Mizuyama (1977), Smart and Jaeggi (1983), Bathurst et al. (1987), Takahashi (1987), Rickenmann (1991); formulae for river regimes which have been tested for (relatively) large flow velocities (large shear stress velocities): Engelund and Hansen (1967), Van Rijn (1984a, 1984c); energetics-based sediment transport conceptions: Bagnold (1963, 1966), Yang (1979), Bagnold-Bailard, see Bailard (1981), Bagnold-Visser, see Visser (1988), these last two formulae are modifications of the original conception of Bagnold (1963, 1966); formulae for debris flows: Takahashi (1978, 1980, 1987, 1991). These sediment transport formulae, combined with Galappatti's model (1983) for the pickup of sediment, are compared with the data of two laboratory experiments (Schelde Flume experiments, see Steetzel and Visser, 1992a, 1992b) and the data of a field experiment (Zwin'89 experiment, see Visser et al., 1990). Experimental sediment transport rates have been determined as volumes of sand eroded over a certain period of time. All tests concern super-critical flow (Froude number Fr > 1, i.e. here 2.8<5 Fr<5 4.1), large values for Shields' mobility parameter (10 < theta < 100) and high concentrations (depth-averaged values rising up to about 0.25 by volume). Most of the tested sediment transport formulae predict sand transport rates being much larger than the observed quantities. Only the Bagnold-Visser formula, see Visser (1988), predicts sand transport rates within a factor two of the experimental values. With the formulation of Van Rijn (1984a, 1984c) this is possible within about a factor three. All other formulae give larger deviations from the experimental data. These conclusions hold for the three initial phases of the process of breach erosion, when the flow is supercritical, and confirm the good results obtained up to now with the BagnoldVisser formula, see Visser (1988, 1994). Once more it should be emphasized that this formula has not been derived for a situation where the rate of sand entrainment is so large as in the first three phases of the breach erosion process (this applies to both the energeticsbased method and the semi-empirical determination of the efficiency factor). The relatively large entrainment of sediment causes a relatively large increase of both the flow rate and the sediment concentration of the sand-water mixture along the inner slope (so that the effect of 'hindered entrainment' is possibly not negligible). Further study is necessary to establish the effects of the large rate of sediment entrainment on the breach erosion process. For the time being it is recommended to apply the formula of Bagnold-Visser in a mathematical breach growth model for the description of the first phases (i.e. as long as the flow is supercritical) of the breach erosion process. The present study does not recommend a formula for the important later phases of breach growth (when the flows becomes subcritical), in which most of the breach erosion takes place and in which also the dimensions of the ultimate breach are determined. Probably the data of the recent Zwin'94 field experiment (see Visser et al, 1995) will allow such a recommendation in the near future. For the present the conclusion of Voogt et al. (1991) is still valid, i.e. that the formulae of Engelund and Hansen (1967) and in particular Van Rijn (1984a, 1984c) can also be applied for relatively large current velocities in subcritical flow.Civil Engineering and Geoscience
- …
