3,776 research outputs found
Ludic literacies at the intersections of cultures: an interview with James Paul Gee
Professor James Gee addresses issues of linguistics, literacies and cultures. Gee emphasises the importance of Discourses, and argues that the future of literacy studies lies in the interrogation of new media and the globalisation of culture
A Study of a Mini-drift GEM Tracking Detector
A GEM tracking detector with an extended drift region has been studied as
part of an effort to develop new tracking detectors for future experiments at
RHIC and for the Electron Ion Collider that is being planned for BNL or JLAB.
The detector consists of a triple GEM stack with a small drift region that was
operated in a mini TPC type configuration. Both the position and arrival time
of the charge deposited in the drift region were measured on the readout plane
which allowed the reconstruction of a short vector for the track traversing the
chamber. The resulting position and angle information from the vector could
then be used to improve the position resolution of the detector for larger
angle tracks, which deteriorates rapidly with increasing angle for conventional
GEM tracking detectors using only charge centroid information. Two types of
readout planes were studied. One was a COMPASS style readout plane with 400
micron pitch XY strips and the other consisted of 2x10mm2 chevron pads. The
detector was studied in test beams at Fermilab and CERN, along with additional
measurements in the lab, in order to determine its position and angular
resolution for incident track angles up to 45 degrees. Several algorithms were
studied for reconstructing the vector using the position and timing information
in order to optimize the position and angular resolution of the detector for
the different readout planes. Applications for large angle tracking detectors
at RHIC and EIC are also discussed.Comment: Submitted to the IEEE Transactions on Nuclear Scienc
Removing Orbital Debris with Lasers
Orbital debris in low Earth orbit (LEO) are now sufficiently dense that the
use of LEO space is threatened by runaway collisional cascading. A problem
predicted more than thirty years ago, the threat from debris larger than about
1 cm demands serious attention. A promising proposed solution uses a high power
pulsed laser system on the Earth to make plasma jets on the objects, slowing
them slightly, and causing them to re-enter and burn up in the atmosphere. In
this paper, we reassess this approach in light of recent advances in low-cost,
light-weight modular design for large mirrors, calculations of laser-induced
orbit changes and in design of repetitive, multi-kilojoule lasers, that build
on inertial fusion research. These advances now suggest that laser orbital
debris removal (LODR) is the most cost-effective way to mitigate the debris
problem. No other solutions have been proposed that address the whole problem
of large and small debris. A LODR system will have multiple uses beyond debris
removal. International cooperation will be essential for building and operating
such a system.Comment: 37 pages, 15 figures, in preparation for submission to Advances in
Space Researc
Forage mixtures for dairy cows: the effect on dry matter intake and milk production in British Friesian dairy cows of incorporating different proportions of maize silage into diets based on grass silage of differing energy value
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MoonLITE – Technological feasibility of the penetrator concept
Introduction: While the surface missions to the Moon of the 1960s and 1970s achieved a great deal, scientifically a great deal was also left unresolved. The recent plethora of lunar missions (flown or proposed) reflects resurgence in interest in the Moon, not only in its own right, but also as a record of the formation of the Earth-Moon System and the interplanetary environment at 1 AU. Results from orbiter missions have indicated the possible presense of ice within permanently shaded craters at the lunar poles [1] – a situation that, if confirmed, will have profound impacts on lunar exploration
NEW ZEALAND BUILT ENVIRONMENT RESEARCH SYMPOSIUM Shaping future directions for collaborative built environment research and practice in New Zealand REFURBISHMENT OF OLD EXISTING BUILDINGS FOR ENERGY CONSERVATION
SYNOPSI
Additive manufacturing method of prototyping novel mm-wave and THz sources
To rapidly prototype novel mm-wave and THz sources there is a requirement to create intricate structures to produce and radiate electromagnetic fields. The motivation for this work is to create improved electron-beam-driven, vacuum electronic mm-wave and sub-THz sources by exploiting dispersion engineering. Although such structures can be manufactured by other techniques, additive manufacturing has proven to be quick, reliable and cost-effective. This research is allowing the prototyping of novel mm-wave and sub-THz coherent sources
Measurement of 30kW output from a W-band source constructed by additive manufacturing
Experimental results from the operation of an electron beam driven, mm-wave, vacuum electronic source are reported. The aim of this work is to create improved electron-beam-driven, vacuum electronic mm-wave and sub-THz sources by exploiting dispersion-engineering. Dispersion-engineered structures can be manufactured by several techniques and in this work additive manufacturing has proven to be quick, reliable and cost-effective
Autofluorescence lifetime augmented reality as a means for real-time robotic surgery guidance in human patients.
Due to loss of tactile feedback the assessment of tumor margins during robotic surgery is based only on visual inspection, which is neither significantly sensitive nor specific. Here we demonstrate time-resolved fluorescence spectroscopy (TRFS) as a novel technique to complement the visual inspection of oral cancers during transoral robotic surgery (TORS) in real-time and without the need for exogenous contrast agents. TRFS enables identification of cancerous tissue by its distinct autofluorescence signature that is associated with the alteration of tissue structure and biochemical profile. A prototype TRFS instrument was integrated synergistically with the da Vinci Surgical robot and the combined system was validated in swine and human patients. Label-free and real-time assessment and visualization of tissue biochemical features during robotic surgery procedure, as demonstrated here, not only has the potential to improve the intraoperative decision making during TORS but also other robotic procedures without modification of conventional clinical protocols
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