5,504 research outputs found
Past veterinarians in South Africa
No full textAn alphabetical list containing short biographies of all deceased South African veterinarians up to 1990.[compiled by] P.J. (Bill) PosthumusVolume 1: AL -- Volume 2: M-ZAlso available in print http://137.215.9.20/record=b1893606ab2013ab201
Defining and evaluating learner experience for social adaptive e-learning
No full textSocial adaptive e-learning combines, threads and balances the amount of social and adaptive features for e-learning in order to achieve high-quality Learner eXperience (LX). Evaluating a social adaptive e-learning system is a difficult task due to its complexity. It is crucial to ensure that appropriate evaluation methods and measures are used. A User-centric approach serves the empirical system evaluation using subjective user feedback on satisfaction and productivity as well as the quality of work and support, so as to verify the quality of product, detect problems, and support decisions. This paper proposes a learner-centric evaluation framework, which applies a user-centric approach, aiming to evaluate LX in social adaptive e-learning from the end-user (learner) point of view, taking into consideration both social and adaptive perspectives
The IPHAS catalogue of H alpha emission-line sources in the northern Galactic plane
No full textWe present a catalogue of point-source H alpha emission-line objects selected from the INT/WFC Photometric Ha Survey (IPHAS) of the northern Galactic plane. The catalogue covers the magnitude range 13 <= r' <= 19.5 and includes Northern hemisphere sources in the Galactic latitude range -5 degrees < b < 5 degrees. It is derived from similar to 1500 deg(2) worth of imaging data, which represents 80 per cent of the final IPHAS survey area. The electronic version of the catalogue will be updated once the full survey data become available. In total, the present catalogue contains 4853 point sources that exhibit strong photometric evidence for Ha emission. We have so far analysed spectra for similar to 300 of these sources, confirming more than 95 per cent of them as genuine emission-line stars. A wide range of stellar populations are represented in the catalogue, including early-type emission-line stars, active late-type stars, interacting binaries, young stellar objects and compact nebulae.
The spatial distribution of catalogue objects shows overdensities near sites of recent or current star formation, as well as possible evidence for the warp of the Galactic plane. Photometrically, the incidence of Ha emission is bimodally distributed in (r' - i'). The blue peak is made up mostly of early-type emission-line stars, whereas the red peak may signal an increasing contribution from other objects, such as young/active low-mass stars. We have cross-matched our H alpha-excess catalogue against the emission-line star catalogue of Kohoutek & Wehmeyer, as well as against sources in SIMBAD. We find that fewer than 10 per cent of our sources can be matched to known objects of any type. Thus IPHAS is uncovering an order of magnitude more faint (r' > 13) emission-line objects than were previously known in the Milky Way
Open brief aan den WelEdel. Gestr. Heer P.J. Joubert
No full textleyds-70-7201.pdf created from original pamphlet in the WJ Leyds Collection held in the Africana Section of the Stellenbosch University Library and Information Service.Dutch open letter to P.J. Joubert concerning a railroad concession granted to the author and two of his friends in 1885
Design, Modeling and Simulation of a 52MHz MEMS Gyroscope Device in 1.5um SOI
No full textIn this thesis , a simulation model of a MEMS gyroscope is presented. The model enables mode matching and analysis of the dynamic behavior of a gyroscope. Furthermore, the model allows the optimization the design parameters of the gyroscope. The simulated gyroscope operates at a frequency of 52MHz with amplitudes of 10nm and quality factor of 50,000. Finally, the drive mode measurements are presented at different bias voltages.Microelectronics & Computer EngineeringElectrical Engineering, Mathematics and Computer Scienc
Het gemeentelijk Investeringsraadsel: Het verband tussen gemeentelijke investeringen en lokale welvaartsontwikkeling
No full textDit proefschrift gaat over de vraag in hoeverre in Nederland de lokale welvaartsontwikkeling wordt bepaald door de gemeentelijke investeringsinspanning. Op project niveau is meestal wel het een en ander bekend over de maatschappelijke effecten, maar over de impact van de totale investeringsinspanning ontbreekt zowel fundamentele als toepasbare kennis. Het is een raadsel dat nog opgelost dient te worden. De doelstelling van dit proefschrift is daaraan een bijdrage te leveren.Housing System
Coupled thermo–hydro–mechanical processes for the Dutch radioactive waste repository
No full textDisposal of spent nuclear fuel and long lived radioactive waste in deep clay geological formations is one of the promising options worldwide. In this concept of the geological disposal system, the Boom Clay is considered as a potential host rock when designing a generic waste repository in the Netherlands. For design and evaluation of a repository for geologic disposal of nuclear wastes one of its principal concern is the thermal loading. High-level radioactive waste and spent fuel generate considerable amounts of heat. When those waste types are disposed in a geological repository the elevated thermal effect on the behaviour of soils surrounding nuclear waste disposal give rise to change in hydraulic and mechanical properties is a significant factor for repository design. Understanding these time-dependent phenomena processes in relation to both the effects of pore water dissipation and of the thermal expansion is essential for reliably assessing repository performance and evaluating the safety case. This paper presents some of the investigation on the thermal processes with emphasis on the coupled Thermo-Hydro- Mechanical (THM) processes for the disposal concept of a radioactive waste disposal facility, in Boom Clay at a depth of about 500m.Geo-engineerin
Probabilistic performance assessment of a deep tunnel for a radioactive waste repository in French COx claystone
No full textA preliminary probabilistic study of the stability of a circular drift excavated for a radioactive waste repository in the French Callovo-Oxfordian claystone is presented and discussed. An analytical mechanical model assuming isotropic elastic behaviour and linear plastic softening was used. Particular emphasis here is placed on the uncertainty of mechanical property values. The test results from several laboratories showed considerably variable property values and they have been interpreted statistically in this investigation. The obtained statistical results were used in a Monte Carlo framework. The performance of the drift was evaluated in terms of the probability of threshold exceedance in the extent of the plastic zone.Geo-engineerin
Achteraf bekeken: Architectuur in Suriname 1951 tot 1969: Bouwwerken ontworpen door ir. P.J. Nagel (1921-1997)
No full textDit boek bestaat hoofdzakelijk uit foto’s van bouwwerken in Suriname, ontworpen door ir. Peter Jacobus Nagel in de periode 1951-1969. Ingenieur P.J. Nagel is afgestudeerd aan de Technische Hogeschool Delft. In dit boek wordt beschreven het leven van Nagel: zijn studietijd, eerste werkkring op Aruba, leven en werken als zelfstandig architect in Suriname van 1951 tot 1963 en tot slot zijn activiteiten in- en vanuit Nederland
Cementbetonnen plaatbekledingen op oevers en dijken, bundeling van artikelen uit de vakpers 1990-1991
No full textCUR; Proefproject: Open colloidaal beton a/s dijkbekleding; PT civiele techniek, april 1990. Burger, A.M., Eversdijk, P.J. en Hendriksma, A.M.; Open cementbeton toegepast a/s bekleding voor dijken; Zeewering Breskens, proefproject voor colloidaal beton; Land + Water, mei 1990. Burger, A.M., Eversdijk, P.J. en Hendriksma, A.M.; Colloidaal beton weerstaat zware storm en hoge golven; De praktijk van open cementbeton a/s Plaatbekleding; Land + Water, juni 1990. CUR; Cementbetonnen plaatbekledingen op dijken; Proefprojecten CUR; Civiele Techniek, No4, 1990. Vrieze, C.G. de; Betonnen dijken, groen a/s gras; Proeven met colloidaal beton voor begroeide rivierdijken; Land + Water No.6, juni 1991. Eversdijk, P.J. en Fase, A.G.; Breuksteen met colloidaal beton pakt rivierdijken goed in; Proefproject Opijnen in Julianakanaal; Land + Water No. 7/8, augustus 1991. Rijke, W.G. de en Burger, A.M.; Cementbetonnen plaatbekledingen op dijken en oevers; Praktische ontwerpmethode (1); Civiele Techniek, jaargang 46, No.3, 1991. Rijke, W.G. de en Burger, A.M.; Cementbetonnen plaatbekledingen op dijken en oevers theoretisch waterdicht; Praktische ontwerpmethode (2); Civiele Techniek, jaargang 46, No.4, 1991. CUR; oemonstratieproject open colloidaal beton Noordoostpolder; Civiele Techniek, No.3, 1991
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