6,805 research outputs found
Cruel Britannia: a personal critique of nursing in the United Kingdom
The United Kingdom (UK) once led the world in nursing but because of the exigencies of the funding mechanisms of the National Health Service (NHS), it has fallen a long way behind other countries. We aim to raise awareness inside and outside the UK about the decline in nursing as a profession there. We are purposely contentious, in an attempt to raise questions, both for the UK and for countries which are recruiting British nurses who are leaving because of job losses caused by the funding crisis in the NHS. This paper discusses where the problems that have led to the decline have come from, where nursing is going and poses questions for the future. We hope that the UK government and those who influence the development of nursing will bring it back to the standard it once bad
Quantum key distribution over 122 km of standard telecom fiber
We report the first demonstration of quantum key distribution over a standard
telecom fiber exceeding 100 km in length. Through careful optimisation of the
interferometer and single photon detector, we achieve a quantum bit error ratio
of 8.9% for a 122km link, allowing a secure shared key to be formed after error
correction and privacy amplification. Key formation rates of up to 1.9 kbit/sec
are achieved depending upon fiber length. We discuss the factors limiting the
maximum fiber length in quantum cryptography
Earth orbital teleoperator mobility system evaluation program
The proximity translation and final docking of the space teleoperator evaluation vehicle (STEV) with large mass and small mass satellites was studied. Operations that may be performed by the STEV during the shuttle experiments are approximated
Earth orbital teleoperator system man-machine interface evaluation
The teleoperator system man-machine interface evaluation develops and implements a program to determine human performance requirements in teleoperator systems
Earth orbital teleoperator systems evaluation
The mechanical extension of the human operator to remote and specialized environments poses a series of complex operational questions. A technical and scientific team was organized to investigate these questions through conducting specific laboratory and analytical studies. The intent of the studies was to determine the human operator requirements for remotely manned systems and to determine the particular effects that various system parameters have on human operator performance. In so doing, certain design criteria based on empirically derived data concerning the ultimate control system, the human operator, were added to the Teleoperator Development Program
Synthesis of 2′‐[F‐18]fluoro‐2′‐DEOXY‐β‐D‐arabinofuranosyl nucleosides
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/91186/1/25804401320_ftp.pd
Gigahertz quantum key distribution with InGaAs avalanche photodiodes
We report a demonstration of quantum key distribution (QKD) at GHz clock
rates with InGaAs avalanche photodiodes (APDs) operating in a self-differencing
mode. Such a mode of operation allows detection of extremely weak avalanches so
that the detector afterpulse noise is sufficiently suppressed. The system is
characterized by a secure bit rate of 2.37 Mbps at 5.6 km and 27.9 kbps at 65.5
km when the fiber dispersion is not compensated. After compensating the fiber
dispersion, the QKD distance is extended to 101 km, resulting in a secure key
rate of 2.88 kbps. Our results suggest that InGaAs APDs are very well suited to
GHz QKD applications.Comment: 4 pages, 4 figure
Coexistence of high-bit-rate quantum key distribution and data on optical fiber
Quantum key distribution (QKD) uniquely allows distribution of cryptographic
keys with security verified by quantum mechanical limits. Both protocol
execution and subsequent applications require the assistance of classical data
communication channels. While using separate fibers is one option, it is
economically more viable if data and quantum signals are simultaneously
transmitted through a single fiber. However, noise-photon contamination arising
from the intense data signal has severely restricted both the QKD distances and
secure key rates. Here, we exploit a novel temporal-filtering effect for
noise-photon rejection. This allows high-bit-rate QKD over fibers up to 90 km
in length and populated with error-free bidirectional Gb/s data communications.
With high-bit rate and range sufficient for important information
infrastructures, such as smart cities and 10 Gbit Ethernet, QKD is a
significant step closer towards wide-scale deployment in fiber networks.Comment: 7 pages, 5 figure
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