1,992 research outputs found
Computer-mediated conferencing
This section addresses issues of Computer-Mediated Conferencing (CMC) as a teaching and learning resource, concentrating upon skills development within that context. The materials are appropriate for different experience levels of learners and provide a range of pathways to the materials and resources as appropriate for any individual learner or learner group
On asymptotic behaviour in truncated conformal space approach
The Truncated conformal space approach (TCSA) is a numerical technique for
finding finite size spectrum of Hamiltonians in quantum field theory described
as perturbations of conformal field theories. The truncation errors of the
method have been systematically studied near the UV fixed point (when the
characteristic energy related to the coupling is less than the truncation
cutoff) where a good theoretical understanding has been achieved. However
numerically the method demonstrated a good agreement with other methods for
much larger values of the coupling when the RG flow approaches a new fixed
point in the infrared. In the present paper we investigate this regime for a
number of boundary RG flows testing the leading exponent and truncation errors.
We also study the flows beyond the first fixed point which have been observed
numerically but yet lack a theoretical understanding. We show that while in
some models such flows approximate reversed physical RG flows, in other models
the spectrum approaches a stable regime that does not correspond to any local
boundary condition. Furthermore we find that in general the flows beyond the
first fixed point are very sensitive to modifications of the truncation scheme.Comment: v2: presentation restructured, general considerations are put forward
into section 2, section on bulk flows removed, quality of all pictures and
referencing improved; 40 pages, 22 figures, 11 tables; to appear in JHE
Automated Detection of Coronal Loops using a Wavelet Transform Modulus Maxima Method
We propose and test a wavelet transform modulus maxima method for the au-
tomated detection and extraction of coronal loops in extreme ultraviolet images
of the solar corona. This method decomposes an image into a number of size
scales and tracks enhanced power along each ridge corresponding to a coronal
loop at each scale. We compare the results across scales and suggest the
optimum set of parameters to maximise completeness while minimising detection
of noise. For a test coronal image, we compare the global statistics (e.g.,
number of loops at each length) to previous automated coronal-loop detection
algorithms
Solar Magnetic Feature Detection and Tracking for Space Weather Monitoring
We present an automated system for detecting, tracking, and cataloging
emerging active regions throughout their evolution and decay using SOHO
Michelson Doppler Interferometer (MDI) magnetograms. The SolarMonitor Active
Region Tracking (SMART) algorithm relies on consecutive image differencing to
remove both quiet-Sun and transient magnetic features, and region-growing
techniques to group flux concentrations into classifiable features. We
determine magnetic properties such as region size, total flux, flux imbalance,
flux emergence rate, Schrijver's R-value, R* (a modified version of R), and
Falconer's measurement of non-potentiality. A persistence algorithm is used to
associate developed active regions with emerging flux regions in previous
measurements, and to track regions beyond the limb through multiple solar
rotations. We find that the total number and area of magnetic regions on disk
vary with the sunspot cycle. While sunspot numbers are a proxy to the solar
magnetic field, SMART offers a direct diagnostic of the surface magnetic field
and its variation over timescale of hours to years. SMART will form the basis
of the active region extraction and tracking algorithm for the Heliophysics
Integrated Observatory (HELIO)
Take Action: 2008 and Beyond
The Organizing Committee for the 2008 Beijing Olympic Games issued the "Beijing Olympic Action Plan," which laid out guiding principles and a series of promises as part of Beijing's preparations to be host city.In 2003,Human Rights in China (HRIC) launched the Incorporating Responsibility 2008 Campaign to encourage Beijing to keep these promises.HRIC issued an initial assessment of Beijing's progress in a 2005 report entitled "Promises, Promises." This update focuses on what has happened over the past two years and what remains to be done before the Games open in August of 2008
Conversion of a mathematics course to CAL: A case study of a large‐scale rapid change of resources and organization
During 1994–95, first‐year maths for the BTechEd degree at the University of Glasgow was student‐centred, teacher‐supported A modular online maths course replaced a traditional, lecture‐based course. Students worked at their own pace, with timetabled and open access computer classes and/or paper handbooks. The course was evaluated by open‐ended measures, and study of examination outcomes, providing us with some pedagogical questions and some recommendations for change. With some adaptation, and with important questions still open, the new course will continue to run
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