39,951 research outputs found
Voorwoord
The development of language policy in the South African educational system, from 1652 to 1961, with special reference to the Union Government period
Vrae rondom die tradisionele bena- dering van die Afrikaanse taalbewe-gings
In this article the traditional approach to the history of the Afrikaans language movements, the so-called âEerste Afrikaanse Taalbewegingâ and âTweede Afrikaanse Taalbewegingâ is criticized, more specifically the traditional evaluation of the relation between the âGenootskap van Regie Afrikanersâ (GRA) and the first language movement. Under discussion is a new concept of what a language movement is, namely that a language movement is determined mainly by a political and I or a religiousforce. In other words, a politically dominant group of people would make use of the sentimental power of their language the mobilize themselves into a political force. Once they have taken over the power of government their language will most likely receive official status. With this âcriterionâ in mind, the history of the Afrikaans language movements can be analyzed against the background of Jive different language movements, i.e. the âOosgrenstaalbewegingâ (I860), the âMaleierafrikaanse taalbewegingâ (1866), the âByvbelvertalingsbeweingâ (1872), the âAfrikanerbondbewegingâ (1880) and the only successful one, the âna-oorlogse taalbewegingâ (1914). The latter succeeded because of the immense success of Afrikaner nationalist politics, not because of the beauty or so-called "wonderâ of the Afrikaans language, as is often believed. TheGRA was no language movement at all, but part of the âBybelvertalingsbewegingâ. The motive behind this language movement was a religious one: to convert the poor Afrikaans speaking population of the Cape Colony to Christianity. An Afrikaans Bible became a bare essential for this mission and thus explains the efforts of Pannevis and later the GRA to translate the Bible into Afrikaans. The whole effort was not to promote Afrikaans as a language at all. Some other facts concerning the erection of the GRA are put into perspective, for instance: the date 14 August 1875, considered as the dale upon which the GRA was formed, has been proved false. A new dale has been decided upon, which is more accurate, namely 25 September of the same year
On the Approximability and Hardness of the Minimum Connected Dominating Set with Routing Cost Constraint
In the problem of minimum connected dominating set with routing cost
constraint, we are given a graph , and the goal is to find the
smallest connected dominating set of such that, for any two
non-adjacent vertices and in , the number of internal nodes on the
shortest path between and in the subgraph of induced by is at most times that in . For general graphs, the only
known previous approximability result is an -approximation algorithm
() for by Ding et al. For any constant , we
give an -approximation
algorithm. When , we give an -approximation
algorithm. Finally, we prove that, when , unless , for any constant , the problem admits no
polynomial-time -approximation algorithm, improving
upon the bound by Du et al. (albeit under a stronger hardness
assumption)
Cosmology with Varying Constants
The idea of possible time or space variations of the `fundamental' constants
of nature, although not new, is only now beginning to be actively considered by
large numbers of researchers in the particle physics, cosmology and
astrophysics communities. This revival is mostly due to the claims of possible
detection of such variations, in various different contexts and by several
groups. Here, I present the current theoretical motivations and expectations
for such variations, review the current observational status, and discuss the
impact of a possible confirmation of these results in our views of cosmology
and physics as a whole.Comment: 14 pages, no figures. Essay to appear in Phil. Trans. Roy. Soc. Lond.
A Triennial Series (Christmas 2002 Issue
Nodeless superconductivity in the noncentrosymmetric MoRhN superconductor: a SR study
The noncentrosymmetric superconductor MoRhN, with K,
adopts a -Mn-type structure (space group 432), similar to that of
MoAlC. Its bulk superconductivity was characterized by magnetization
and heat-capacity measurements, while its microscopic electronic properties
were investigated by means of muon-spin rotation and relaxation (SR). The
low-temperature superfluid density, measured via transverse-field (TF)-SR,
evidences a fully-gapped superconducting state with , very close to 1.76 - the BCS gap value for
the weak coupling case, and a magnetic penetration depth nm.
The absence of spontaneous magnetic fields below the onset of
superconductivity, as determined by zero-field (ZF)-SR measurements, hints
at a preserved time-reversal symmetry in the superconducting state. Both TF-and
ZF-SR results evidence a spin-singlet pairing in MoRhN.Comment: 5 figures and 5 pages. Accepted for publication as a Rapid
Communication in Phys. Rev.
Coexistence of localized and itinerant electrons in BaFe2X3 (X = S and Se) revealed by photoemission spectroscopy
We report a photoemission study at room temperature on BaFe2X3 (X = S and Se)
and CsFe2Se3 in which two-leg ladders are formed by the Fe sites. The Fe 2p
core-level peaks of BaFe2X3 are broad and exhibit two components, indicating
that itinerant and localized Fe 3d sites coexist similar to KxFe2-ySe2. The Fe
2p core-level peak of CsFe2Se3 is rather sharp and is accompanied by a
charge-transfer satellite. The insulating ground state of CsFe2Se3 can be
viewed as a Fe2+ Mott insulator in spite of the formal valence of +2.5. The
itinerant versus localized behaviors can be associated with the stability of
chalcogen p holes in the two-leg ladder structure.Comment: 5 pages, 5 figures, Accepted in publication for Physical Review
A New Method of Measuring 81Kr and 85Kr Abundances in Environmental Samples
We demonstrate a new method for determining the 81Kr/Kr ratio in
environmental samples based upon two measurements: the 85Kr/81Kr ratio measured
by Atom Trap Trace Analysis (ATTA) and the 85Kr/Kr ratio measured by Low-Level
Counting (LLC). This method can be used to determine the mean residence time of
groundwater in the range of 10^5 - 10^6 a. It requires a sample of 100 micro-l
STP of Kr extracted from approximately two tons of water. With modern
atmospheric Kr samples, we demonstrate that the ratios measured by ATTA and LLC
are directly proportional to each other within the measurement error of +/-
10%; we calibrate the 81Kr/Kr ratio of modern air measured using this method;
and we show that the 81Kr/Kr ratios of samples extracted from air before and
after the development of the nuclear industry are identical within the
measurement error
Cider: a Rapid Docker Container Deployment System through Sharing Network Storage
Container technology has been prevalent and widely-adopted in production environment considering the huge benefits to application packing, deploying and management. However, the deployment process is relatively slow by using conventional approaches. In large-scale concurrent deployments, resource contentions on the central image repository would aggravate such situation. In fact, it is observable that the image pulling operation is mainly responsible for the degraded performance. To this end, we propose Cider - a novel deployment system to enable rapid container deployment in a high concurrent and scalable manner at scale. Firstly, on-demand image data loading is proposed by altering the local Docker storage of worker nodes into all-nodes-sharing network storage. Also, the local copy-on-write layer for containers can ensure Cider to achieve the scalability whilst improving the cost-effectiveness during the holistic deployment. Experimental results reveal that Cider can shorten the overall deployment time by 85% and 62% on average when deploying one container and 100 concurrent containers respectively
Zener Tunneling Between Landau Orbits in a High-Mobility Two-Dimensional Electron Gas
Magnetotransport in a laterally confined two-dimensional electron gas (2DEG)
can exhibit modified scattering channels owing to a tilted Hall potential.
Transitions of electrons between Landau levels with shifted guiding centers can
be accomplished through a Zener tunneling mechanism, and make a significant
contribution to the magnetoresistance. A remarkable oscillation effect in weak
field magnetoresistance has been observed in high-mobility 2DEGs in
GaAs-AlGaAs heterostructures, and can be well explained by the
Zener mechanism.Comment: 5 pages, 4 figures. Text slightly shortened, figures resize
Effective Mass of the Four Flux Composite Fermion at
We have measured the effective mass () of the four flux composite
fermion at Landau level filling factor (CF), using the
activation energy gaps at the fractional quantum Hall effect (FQHE) states
= 2/7, 3/11, and 4/15 and the temperature dependence of the Shubnikov-de
Haas (SdH) oscillations around . We find that the energy gaps show a
linear dependence on the effective magnetic field (), and from this linear dependence we obtain and
a disorder broadening 1 K for a sample of density /cm. The deduced from the temperature dependence of
the SdH effect shows large differences for and . For
, . It scales as with the mass
derived from the data around and shows an increase in as , resembling the findings around . For ,
increases rapidly with increasing and can be described by . This anomalous dependence on is
precursory to the formation of the insulating phase at still lower filling.Comment: 5 pages, 3 figure
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