3,755 research outputs found
Blended learning: A new approach to legal teaching in South African law schools
This article investigates the development of a sustainable strategy for the integration of online education technology and traditional teaching and learning methodologies in South African law faculties, in a so-called ‘blended learning’ approach to legal teaching. In developing a strategy, a number of issues were considered, including: accommodating an increasing and diverse student population; achieving SAQA exit-level outcomes; national and international trends in blended learning; and ensuring an appropriate level of computer skills for both lecturers and students. Vital to the development of a sustainable strategy is a comprehensive management plan which details clear objectives for the process of implementation.The achievement of the management plan objectives should be driven by a project management team, which will be responsible for conducting training and support in blended learning; developing online learning module materials; producing research into technological advancements in this field; co-operating with the law library; establishing a committed blended learning community; and finally establishing a system of blended learning module review.The overall objective of the strategy then, is to establish a sustainable model for the medium and long-term implementation of blended learning, ensuring that this mode of learning becomes accepted as an integral part of the system of legal education in the institution
Interaction between Faraday rotation and Cotton-Mouton effects in polarimetry modeling for NSTX
The evolution of electromagnetic wave polarization is modeled for propagation
in the major radial direction in the National Spherical Torus Experiment (NSTX)
with retroreflection from the center stack of the vacuum vessel. This modeling
illustrates that the Cotton-Mouton effect-elliptization due to the magnetic
field perpendicular to the propagation direction-is shown to be strongly
weighted to the high-field region of the plasma. An interaction between the
Faraday rotation and Cotton-Mouton effects is also clearly identified.
Elliptization occurs when the wave polarization direction is neither parallel
nor perpendicular to the local transverse magnetic field. Since Faraday
rotation modifies the polarization direction during propagation, it must also
affect the resultant elliptization. The Cotton-Mouton effect also intrinsically
results in rotation of the polarization direction, but this effect is less
significant in the plasma conditions modeled. The interaction increases at
longer wavelength, and complicates interpretation of polarimetry measurements.Comment: Contributed paper published as part of the Proceedings of the 18th
Topical Conference on High-Temperature Plasma Diagnostics, Wildwood, New
Jersey, May, 201
Fluid Mechanical and Electrical Fluctuation Forces in Colloids
Fluctuations in fluid velocity and fluctuations in electric fields may both
give rise to forces acting on small particles in colloidal suspensions. Such
forces in part determine the thermodynamic stability of the colloid. At the
classical statistical thermodynamic level, the fluid velocity and electric
field contributions to the forces are comparable in magnitude. When quantum
fluctuation effects are taken into account, the electric fluctuation induced
van der Waals forces dominate those induced by purely fluid mechanical motions.
The physical principles are applied in detail for the case of colloidal
particle attraction to the walls of the suspension container and more briefly
for the case of forces between colloidal particles.Comment: ReVTeX format, one *.eps figur
Microrheology probes length scale dependent rheology
We exploit the power of microrheology to measure the viscoelasticity of entangled F-actin solutions at different length scales from 1 to 100 mu m over a wide frequency range. We compare the behavior of single probe-particle motion to that of the correlated motion of two particles. By varying the average length of the filaments, we identify fluctuations that dissipate diffusively over the filament length. These provide an important relaxation mechanism of the elasticity between 0.1 and 30 rad/sec
Galactic center at very high-energies
Employing data collected during the first 25 months' observations by the
Fermi-LAT, we describe and subsequently seek to model the very high energy
(>300 MeV) emission from the central few parsecs of our Galaxy. We analyze the
morphological, spectral and temporal characteristics of the central source,
1FGL J1745.6-2900. Remarkably, the data show a clear, statistically significant
signal at energies above 10 GeV, where the Fermi-LAT has an excellent angular
resolution comparable to the angular resolution of HESS at TeV energies, which
makes meaningful the joint analysis of the Fermi and HESS data. Our analysis
does not show statistically significant variability of 1FGL J1745.6-2900. Using
the combination of Fermi data on 1FGL J1745.6-2900 and HESS data on the
coincident, TeV source HESS J1745-290, we show that the spectrum of the central
gamma-ray source is inflected with a relatively steep spectral region matching
between the flatter spectrum found at both low and high energies. We seek to
model the gamma-ray production in the inner 10 pc of the Galaxy and examine, in
particular, cosmic ray (CR) proton propagation scenarios that reproduce the
observed spectrum of the central source. We show that a model that instantiates
a transition from diffusive propagation of the CR protons at low energy to
almost rectilinear propagation at high energies (given a reasonable
energy-dependence of the assumed diffusion coefficient) can well explain the
spectral phenomenology. In general, however, we find considerable degeneracy
between different parameter choices which will only be broken with the addition
of morphological information that gamma-ray telescopes cannot deliver given
current angular resolution limits.We argue that a future analysis done in
combination with higher-resolution radio continuum data holds out the promise
of breaking this degeneracy.Comment: submitted to Ap
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