Now showing items 21-40 of 3813

• #### Probing the universe with cosmic rays using high performance computing ﻿

(ASSAf, 2008)
I report on the research activities of the South African Centre for High Performance Computing carried out at the Unit for Space Physics at North-West University, Potchefstroom, during 2007/8. Background is given on the ...
• #### Are anomalous cosmic rays the main contribution to the low-energy galactic cosmic ray spectrum? ﻿

(IOP Publishing, 2008)
While the high-energy part of the Galactic cosmic ray spectrum is well observed, its nature at energies below about 1 GeV nucleon-1 is still not known well. Recent in situ measurements made with the Voyager 1 spacecraft in ...
• #### Challenges to cosmic ray modeling: from beyond the solar wind termination shock ﻿

(Elsevier, 2008)
Voyager 1 crossed the solar wind termination shock on December 16, 2004 at a distance of 94 AU from the Sun, to become the first spacecraft to explore the termination shock region and to enter the heliosheath, the final ...
• #### Investigation of the multiple-component structure of the 20 January 2005 cosmic ray ground level enhancement ﻿

(American Geophysical Union, 2008)
Worldwide observations of the cosmic ray ground level enhancement (GLE) of 20 January 2005 are used to investigate a commonly observed but poorly understood feature of this class of event. It is argued that the GLE ...
• #### A calibration neutron monitor: energy response and instrumental temperature sensitivity ﻿

(American Geophysical Union, 2008)
Neutron monitors are integral detectors of secondary cosmic rays. Since each of them has its own detection efficiency, energy spectra cannot readily be derived from their observations. To circumvent this problem, latitudinal ...
• #### Discovery of VHE gamma-rays from the high-frequency-peaked BL Lacertae object RGB J0152+017 ﻿

(EDP Sciences, 2008)
Aims. The BL Lac object RGB J0152+017 (z=0.080) was predicted to be a very high-energy (VHE; >100 GeV) $\gamma$-ray source, due to its high X-ray and radio fluxes. Our aim is to understand the radiative processes by ...
• #### Soil quality as a key success factors in sustainable rehabilitation of kimberlite mine waste ﻿

(SAIMM (The South African Institution of Mining and Metallurgy), 2008)
• #### Trichloroacetic acid of different origin in Norway spruce needles and chloroplasts ﻿

(Springer Netherlands, 2008)
Trichloroacetic acid (TCA), a secondary atmospheric pollutant, is also formed in forest soil and thus ranked among natural organohalogens. The observed biooxidation of atmospheric tetrachloroethene (PER) to TCA in chloroplasts ...
• #### HESS very-high-energy gamma-ray sources without identified counterparts ﻿

(EDP sciences, 2008)
Context.The detection of gamma rays in the very-high-energy (VHE) energy range (100 GeV–100 TeV) provides a direct view of the parent population of ultra-relativistic particles found in astrophysical sources. For this ...
• #### HESS upper limits for Kepler's supernova remnant ﻿

(EDP sciences, 2008)
Aims. Observations of Kepler's supernova remnant (G4.5+6.8) with the HESS telescope array in 2004 and 2005 with a total live time of 13 h are presented. Methods. Stereoscopic imaging of Cherenkov radiation from extensive ...
• #### A new species of Adelphryne (Anura: Eleutherodactylidae) from Guyana, with additional data on A. gutturosa ﻿

(Magnolia Press, 2008)
A new species of frog, Adelophryne patamona, from 678-1414 m elevation in the Pakaraima Mountains of Guyana, is described. The new species is distinguished by large size, second phalange of Finger IV longer than wide, tips ...
• #### Constraints on injection parameters of cosmic rays in the Galactic center from resolved HESS observations ﻿

(Elsevier Ltd., 2008)
• #### The continuous depolymerization of filled polytetrafluoroethylene with a continuous process ﻿

(Wiley InterScience, 2008)
• #### A kinetic expression for the pyrolytic decomposition of polyterafluoroethylene ﻿

(Elsevier Science Limited, 2008)
• #### Contributions from nearby pulsars to the local cosmic ray electron spectrum ﻿

(Elsevier, 2008)
PSR J0437-4715 is one of the closest millisecond pulsars (MSPs) to Earth, lying at a distance of ∼140 pc. This pulsar has a characteristic age of 4.9 Gyr and a relatively low spindown power of ∼1034 ergs/s. During its ...

(2008)
• #### A mathematics vocabulary questionnaire for use in the intermediate phase ﻿

(Education Association of South Africa (EASA), 2008)
Teachers and psychologists need an instrument to assess learners’ language proficiency in mathematics to enable them to plan and evaluate interventions and to facilitate best practice in mathematics classrooms. We describe ...
• #### Optimal auditing in the banking industry ﻿

(Wiley, 2008)
As a result of the new regulatory prescripts for banks, known as the Basel II Capital Accord, there has been a heightened interest in the auditing process. Our paper considers this issue with a particular emphasis on the ...
• #### Optimal allocation between bank loans and treasuries with regret ﻿

(Springer, 2008)
The main categories of assets held by banks are loans, Treasuries (bonds issued by the national Treasury), reserves and intangible assets. In our contribution, we investigate the investment of bank funds in loans and ...
• #### Ekonometriese modelle in finansiële risiko ﻿

(AOSIS, 2008)
This paper provides an overview of the contributions by prof JH Venter to financial risk and volatility modelling, estimation and forecasting. Venter's research is based on the classical GARCH model which he refines in ...

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