4,544 research outputs found
Metadata is the key to collaboration and a national bibliographic knowledgebase
The British Library has partnered with Jisc, Research Libraries UK (RLUK) and the Society of College, National and University Libraries (SCONUL) to create a national bibliographic knowledgebase (NBK). Neil Wilson outlines why such an initiative is necessary, explaining the implications of a hybrid print/digital marketplace, and how the rapidly evolving digital landscape has not been matched by a parallel development in the quality of metadata available to describe it. The NBK will ensure libraries can provide researchers and students with quicker, more efficient access to digital books and resources by aggregating and interoperating with a collection of data sources to discover where books are kept, in what format and the terms of their availability
An Intelligent Fuse-box for use with Renewable Energy Sources integrated within a Domestic Environment
This paper outlines a proposal for an intelligent fuse-box that can replace existing fuse-boxes in a domestic context such that a number of renewable energy sources can easily be integrated into the domestic power supply network, without the necessity for complex islanding and network protection. The approach allows intelligent control of both the generation of power and its supply to single or groups of electrical appliances. Energy storage can be implemented in such a scheme to even out the power supplied and simplify the control scheme required, and environmental monitoring and load analysis can help in automatically controlling the supply and demand profiles for optimum electrical and economic efficiency. Simulations of typical scenarios are carried out to illustrate the concept in operation
Rose Of My Heart (Rose De Mon Coeur)
https://digitalcommons.library.umaine.edu/mmb-vp/6620/thumbnail.jp
The use of telemedicine to assess a paediatric patient with arrhythmia presenting to a remote community coronavirus assessment centre
Peer reviewedPublisher PD
Electronic transport in single-walled carbon nanotubes, and their application as scanning probe microscopy tips
Single-walled carbon nanotubes (SWNTs) are remarkable molecules composed
of a graphite sheet rolled into a seamless cylinder. With nanometer diameter,
and micrometer length, their physical properties are due to a mixture of quantum
and classical effects. This work investigates the electrical transport properties of
these molecules, and demonstrates their application as Atomic Force Microscopy
(AFM) tips.
SWNTs were grown by catalysed chemical vapour deposition (cCVD), and
characterized using AFM, electron microscopy and Raman spectroscopy. Electronic
devices were fabricated from SWNTs grown by cCVD on Si02. Electronic transport
through the SWNT devices was studied using electric force microscopy (EFM) and
scanned gate microscopy (SGM). SGM was used to study the effects of defects on
transport through the devices. A novel form of SGM, based on the modulation of
the tip-gating potential by the oscillating tip in dynamic mode AFM, was demonstrated
and shown to massively enhance the signal to noise ratio. Using EFM we
directly demonstrated the transition from ballistic transport in metallic SWNT at
low source-drain voltages, to diffusive transport at high-source drain voltages. EFM
was also used to image the charge injection induced around a SWNT at high gate
voltages, and correlate it with the observed hysteresis in the transconductance of
SWNT devices. Both of these results are of fundamental importance to the future
applications of SWNT electronic devices. The high bias behaviour of metallic SWNT
is crucial to their proposed use as interconnects in nanoscale devices. Hysteresis in
the transconductance of semiconducting SWNT devices is limiting their application
as chemical and biological sensors, where environmental effects are monitored by
the change in conductance of the devices.
SWNTs were mounted at the apex of AFM tips, and used as high resolution
scanning probe tips. Electrical transport through the SWNT-AFM tips was
investigated using both liquid (Hg) and solid contacts. An efficient technique for
fabricating nanowire AFM tips, using SWNT-AFM tips as templates, was also invented.
The resultant nanowire tips were shown to be robust, high aspect ratio,
electrical probes. Using calibration samples fabricated from SWNTs, SWNT-AFM
tips were quantitatively demonstrated to increase the resolution of EFM. Under
optimal conditions identical features could be distinguished down to separations as
low as 15 nm, comparable to the topographic resolution
Radio Cores in Low-Luminosity AGN: ADAFs or Jets?
We have surveyed two large samples of nearby low-luminosity AGN with the VLA
to search for flat-spectrum radio cores, similar to Sgr A* in the Galactic
Center. Roughly one third of all galaxies are detected (roughly one half if HII
transition objects are excluded from the sample), many of which have compact
radio cores. Follow-up observations with the VLBA have confirmed that these
cores are non-thermal in origin, with lower limits for the brightness
temperatures around ~10^8 K. The brightest of these are resolved into linear
structures. The radio spectral indices of the cores are quite flat (alpha~0),
with no evidence for the highly inverted radio cores predicted in the ADAF
model. Spectrum and morphology of the compact radio emission is typical for
radio jets seen also in more luminous AGN. The emission-line luminosity seems
to be correlated with the radio core flux. Together with the VLBI observations
this suggests that optical and radio emission in at least half the
low-luminosity Seyferts and LINERs are black hole powered. We find only a weak
correlation between bulge luminosity and radio flux and an apparently different
efficiency between elliptical and spiral galaxies for producing radio emission
at a given optical luminosity.Comment: 5 pages, 2 figures, (ESO) LaTex, to appear in ``Black Holes in
Binaries and Galactic Nuclei'', ESO workshop, eds. L. Kaper, E.P.J. van den
Heuvel, P.A. Woudt, Springer Verlag; also available at
http://www.mpifr-bonn.mpg.de/staff/hfalcke/publications.html#eso9
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