Browsing by Subject "Diffusion"
Now showing items 1-10 of 40
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An ab initio approach to the heliospheric modulation of galactic cosmic rays
(North-West University, 2006)In the present study we aim to further our understanding of charged particle transport in a magnetized medium. To this end, we perform direct numerical simulations of particle transport in a turbulent magnetic field. From ... -
Adoption and diffusion of open source software in Tanzania: a way forward
(IST-Africa, 2013)The use of ICT in world has increased significantly in the last two decades. This increase is far pronounced in developing countries. While the use of ICT promises to be a major instrument in poverty reduction, it is clear ... -
Correlation of long-term cosmic-ray modulation with solar activity parameters
(IOP Publishing, 2019)In this work, we analyze the long-term cosmic-ray modulation observed by the Hermanus neutron monitor, which is the detector with the longest cosmic-ray record, from 1957 July. For our study we use the force-field approximation ... -
Determining pitch-angle diffusion coefficients from test particle simulations
(IOP Publishing, 2016)The transport and acceleration of charged particles in turbulent media are topics of great interest in space physics and interstellar astrophysics. These processes are dominated by the scattering of particles off magnetic ... -
The development of a fuzzy expert system to aid in the adoption and use of systems development methodologies
(North-West University, 2009)A topic of great interest to the field of information system (IS) development is the concept of systems development methodologies (SDMs) and their successful adoption by, and use in, an organisation. Therefore, there ... -
Diffusion in pulsar wind nebulae: an investigation using magnetohydrodynamic and particle transport models
(Oxford Univ Press, 2016)We study the transport of high-energy particles in pulsar wind nebulae (PWN) using three-dimensional magnetohydrodynamic (MHD) and test-particle simulations, as well as a Fokker–Planck particle transport model. The latter ... -
Dissipative particle dynamics investigation of the transport of salicylic acid through a simulated in vitro skin permeation model
(MDPI, 2018)Permeation models are often used to determine diffusion properties of a drug through a membrane as it is released from a delivery system. In order to circumvent problematic in vivo studies, diffusion studies can be ... -
The effect of a dynamic inner heliosheath thickness on cosmic-ray modulation
(IOP Publishing, 2015)The time-dependent modulation of galactic cosmic rays in the heliosphere is studied over different polarity cycles by computing 2.5 GV proton intensities using a two-dimensional, time-dependent modulationmodel. By ... -
The effect of diffusion on the particle spectra in pulsar wind nebulae
(IOP Publishing, 2013)A possible way to calculate particle spectra as a function of position in pulsar wind nebulae is to solve a Fokker–Planck transport equation. This paper presents numerical solutions to the transport equation with the ... -
The effect of drift on the evolution of the electron/positron spectra in an axisymmetric pulsar wind nebula
(IOP Publishing, 2014)Charged particles propagating through a structured magnetic field are subject to drift motion. The primary aim of the present paper is therefore to investigate the effects of gradient, curvature, and neutral sheet drift ...
