31,381 research outputs found
Group facilitation skills for participatory decision-making: report of a follow-up outcome evaluation
This working paper reports on an evaluation designed to assess the usefulness of the skills gained during the training course, if the skills learned have been applied and, if so, how the new facilitation tools and techniques have changed meeting processes. The evaluation also identified obstacles to the use of new skills faced by participants, additional follow-on activities that have been conducted by participants, and other related skills that are needed to complement what was learned in the ILAC facilitation course
Modelling the spectral energy distribution of galaxies from the ultraviolet to submillimeter
We present results from a new modelling technique which can account for the
observed optical/NIR - FIR/submm spectral energy distributions (SEDs) of normal
star-forming galaxies in terms of a minimum number of essential parameters
specifying the star-formation history and geometrical distribution of stars and
dust. The model utilises resolved optical/NIR images to constrain the old
stellar population and associated dust, and geometry-sensitive colour
information in the FIR/submm to constrain the spatial distributions of young
stars and associated dust. It is successfully applied to the edge-on spirals
NGC891 and NGC5907. In both cases the young stellar population powers the bulk
of the FIR/sub-mm emission. The model also accounts for the observed surface
brightness distribution and large-scale radial brightness profiles in NGC891 as
determined using the Infrared Space Observatory (ISO) at 170 and 200 mcrions
and at 850 micron using SCUBA.Comment: 20 pages (Latex), Highlight talk at the Joint European and National
Astronomical Meeting JENAM 2001, to be published in Reviews in Modern
Astronomy 15: Five Days of Creation: Astronomy with Large Telescopes from
Ground and Base. Germany : Astronomische Gesellschaft, 200
Topological Sound and Flocking on Curved Surfaces
Active systems on curved geometries are ubiquitous in the living world. In
the presence of curvature orientationally ordered polar flocks are forced to be
inhomogeneous, often requiring the presence of topological defects even in the
steady state due to the constraints imposed by the topology of the underlying
surface. In the presence of spontaneous flow the system additionally supports
long-wavelength propagating sound modes which get gapped by the curvature of
the underlying substrate. We analytically compute the steady state profile of
an active polar flock on a two-sphere and a catenoid, and show that curvature
and active flow together result in symmetry protected topological modes that
get localized to special geodesics on the surface (the equator or the neck
respectively). These modes are the analogue of edge states in electronic
quantum Hall systems and provide unidirectional channels for information
transport in the flock, robust against disorder and backscattering.Comment: 15 pages, 6 figure
Normal Nearby Galaxies
Following on from IRAS, ISO has provided a huge advancement in our knowledge
of the phenomenology of the infrared (IR) emission of normal galaxies and the
underlying physical processes. Highlights include: the discovery of an extended
cold dust emission component, present in all types of gas-rich galaxies and
carrying the bulk of the dust luminosity; the definitive characterisation of
the spectral energy distribution in the IR, revealing the channels through
which stars power the IR light; the derivation of realistic geometries for
stars and dust from ISO imaging; the discovery of cold dust associated with HI
extending beyond the optical body of galaxies; the remarkable similarity of the
near-IR (NIR)/ mid-IR (MIR) SEDs for spiral galaxies, revealing the importance
of the photo-dissociation regions in the energy budget for that wavelength
range; the importance of the emission from the central regions in shaping up
the intensity and the colour of the global MIR luminosity; the discovery of the
``hot'' NIR continuum emission component of interstellar dust; the predominance
of the diffuse cold neutral medium as the origin for the main interstellar
cooling line, [CII] 158 micron, in normal galaxies.Comment: 47 pages, 15 figures, to be published in the ISO Special Issue of
Space Science Reviews: "ISO science legacy - a compact review of ISO major
achievements", Springer 2005. See http://www.iso.vilspa.esa.es/science/SSR/
for a higher resolution version and for all papers in the volum
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