15,983 research outputs found
Darren Clarke
No full textI was driving around to East Point when I noticed an Indigenous man spear fishing just off shore from the B.B.Q. area. When Bluey (Dimiliny Burarrwanga), (which I found out later was his name) first noticed me he was totally surprised and immediately suspicious about what I wanted him for, but after a short discussion in which I explained that I was making images for the Northern Territory Library's collection, Bluey agreed to allow me to make some images as he hunted for string ray. With in ten minutes Bluey had a small ray on the end of his spear, mission accomplished. We both made our way back to shore where Bluey's family where waiting quietly for him under the she oaks. I was introduced to everyone and spent the rest of the afternoon talking, eating, and making images with the other members of the family.Clark, Darren.Date:2012-0
Dropper’s – Andy Webster & Darren Ray OSR Projects Lobster Trap Commission 2016
No full textIn 1965 Gene Bernofsky, Jo Ann Bernofsky and Clark Richet, art graduates of the University of Kansas desired to live and work together free from the hierarchies and restrictions of mainstream life. On a piece of wasteland near Trinidad, Colorado they built an experimental settlement named ‘Drop City' with the aim being for the site to be an environmental research centre, a collaborative space for artists, inventors, free‐thinkers and collectives who wished to celebrate creative experimentation. This group of people who became known as ‘Droppers’, established a non-hierarchical community, openly sharing ideas, collectively living and working together and this was seen as the goal and potential of counter cultural attitudes of the time, a kind of socialist psychedelica. 50 years on do the Droppers thoughts and ideals still have relevance? What might the practice of the ‘psychedelic socialism’ mean or offer us today? In what ways might we still be looking for the this kind of life - might it produce alternative modes of living often suppressed by immanent capitalism? Collaborative artist’s Andy Webster and Darren Ray propose to explore these questions in their project ‘Dropper’s.
[Letter from Alex Bradford to Lieutenant and Mrs. Ray Starner - November 4, 1940]
No full textLetter from Alex Bradford to Lieutenant and Mrs. Ray Starner describing the the current state of affairs that the author was experiencing, including: the London blitz, the moral of the troops on the ground, and the collective company of men opposing the Nazi regime
Arlene's Solar Furnace - Andy Webster & Darren Ray, 2015
No full textIn 2008, Arlene built a Solar Furnace, a structure that uses concentrated solar energy to produce high temperatures, to heat her farm in Pennsylvania, USA. Ray and Webster are fascinated by the ad-hoc approaches found in DIY, hobbyist activities in particular the kind epitomised by Arlene's project which measuring 24ft by 8ft her project was pretty incredible. Arlene's construction of the furnace, the use of regular non-specialist materials, and her matter of fact description of the project uploaded online inspired Ray & Webster to explore the approaches behind the furnaces construction. They replicated Arlene's project working as closely to as possible to the original specifications of the furnace (although perhaps in keeping with the approach of the original they improvised many of the construction processes and materials used). The project was installed as part of Goonhilly Village Green, Goohnilly, Lizard Peninsula, Cornwall, UK, 2015
The student's guide to completing an author study
No full textThe 'Student's guide to completing an author study' emerged during the early development of the school library resource center program at Glen Stewart Elementary School in Stratford Canada on Prince Edward Island. This research process centered on an author study, with direct teaching and clear assignment. The resulting model has been adapted to various grade levels and subject areas in different schools.Source type: Electronic(1)http://proquest.umi.com/pqdweb?did=49237063&Fmt=7&clientId=65345&RQT=309&VName=PQ
Active X-ray optics for the next generation of X-ray space telescopes
No full textDescribed within is the design, manufacture, metrology and X-ray testing of an active X-ray
prototype intended for the next generation of X-ray telescopes. One of the challenges faced by
the X-ray telescope community is how to combine high resolution and high sensitivity into one
system, as weight limitations place constraints on the optics that can be launched. Therefore the
mandate of the active X-ray prototype is to provide high sensitivity through the ability of the optics
to be nested and to deliver high angular resolution through the active control of the optic’s form.
Piezoelectric unimorph actuators provide the active component: it is intended that they will correct
for figure errors within the optic and therefore increase the angular resolution capability.
The prototype’s design is based upon an ellipsoidal segment which provides point-to-point
focussing of an X-ray source. The prototype itself is composed of an electroformed nickel optic
where the non-reflective surface is populated with 30 piezoelectric actuators and it is the production
of the prototype that is the core of the presented research. Metrology of the actuators’ influence
functions is presented and highlight the prototype’s ability to deform its optic surface by microns.
In addition, the measured influence functions are compared against finite element models and a
distinct similarity between the functions is observed.
The prototype was tested at an X-ray beamline facility in November 2008 and the results
showed the prototype’s ability to correct the optic to achieve an improved angular resolution: from
0.786 arc-minutes to 0.686 arc-minutes in terms of full width half maximum. Finally, difficulties
in the manufacture of the prototype and X-ray testing shall be presented alongside future work in
conclusion to this thesis
Author, Geraldine Brooks at the National Library of Australia for the 2009 Ray Mathew Lecture, Canberra, 23 October 2009 [picture] /
No full textTitle from acquisitions documentation.; Part of the collection: Portraits of author, Geraldine Brooks during her visit to the National Library of Australia for the 2009 Ray Mathew Lecture, Canberra, 23 October 2009.; Acquired in digital format; access copy available online.; Mode of access: Internet via World Wide Web.; Photographed by a staff member of the National Library of Australia
A 2 h periodic variation in the low-mass X-ray binary Ser X-1
No full textSpectroscopy of the low-mass X-ray binary Ser X-1 using the Gran Telescopio Canarias have revealed a ?2 h periodic variability that is present in the three strongest emission lines. We tentatively interpret this variability as due to orbital motion, making it the first indication of the orbital period of Ser X-1. Together with the fact that the emission lines are remarkably narrow, but still resolved, we show that a main-sequence K dwarf together with a canonical 1.4 M? neutron star gives a good description of the system. In this scenario, the most likely place for the emission lines to arise is the accretion disc, instead of a localized region in the binary (such as the irradiated surface or the stream-impact point), and their narrowness is due instead to the low inclination (?10°) of Ser X-1
X-ray polarization in relativistic jets
No full textWe investigate the polarization properties of Comptonized X-rays from relativistic jets in active galactic nuclei (AGN) using Monte Carlo simulations. We consider three scenarios commonly proposed for the observed X-ray emission in AGN: Compton scattering of blackbody photons emitted from an accretion disc; scattering of cosmic microwave background (CMB) photons and self-Comptonization of intrinsically polarized synchrotron photons emitted by jet electrons. Our simulations show that for Comptonization of disc and CMB photons, the degree of polarization of the scattered photons increases with the viewing inclination angle with respect to the jet axis. In both cases, the maximum linear polarization is ≈20 per cent. In the case of synchrotron self-Comptonization (SSC), we find that the resulting X-ray polarization depends strongly on the seed synchrotron photon injection site, with typical fractional polarizations P≈ 10–20 per cent when synchrotron emission is localized near the jet base, while P≈ 20–70 per cent for the case of uniform emission throughout the jet. These results indicate that X-ray polarimetry may be capable of providing unique clues to identify the location of particle acceleration sites in relativistic jets. In particular, if synchrotron photons are emitted quasi-uniformly throughout a jet, then the observed degree of X-ray polarization may be sufficiently different for each of the competing X-ray emission mechanisms (synchrotron, SSC or external Comptonization) to determine which is the dominant process. However, X-ray polarimetry alone is unlikely to be able to distinguish between disc and CMB Comptonization
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Observations of the 57Fe+23 hyperfine transition in clusters of galaxies
No full textWe present a search for the hyperfine transition of the 57Fe+23 ion at 3.071 mm in clusters of galaxies with the ATNF Mopra telescope. The results are compared with a realistic estimate of the peak brightness temperature of the line in a cooling flow cluster A85, using the available X-ray data
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