27,211 research outputs found
Recommended from our members
Clinical users' perspective on telemonitoring of patients with long term conditions: Understood through concepts of Giddens's structuration theory & consequence of modernity
This is the post-print version of the article - Copyright @ 2010 IOS.This study involves conducting focus group discussions with clinical users (nurses and technicians) prior to the launch of telehealth service in Nottingham, UK, to elicit their initial perceptions about the service. It describes the findings from preliminary phase of otherwise a larger longitudinal study. Using Giddens’s concepts from structuration theory and con-sequence of modernity, we were able to acknowledge trust and sense of security as two very salient aspects that govern adop-tion of new technological innovation. Unattended, these as-pects contribute to arousal of conflict and contradiction within a system. In order for successful telehealth implementa-tions in health care setting, providers of the service, need to focus on ways in which clinical users’ trust can be gained and sense of security can be promoted while using the telehealth service and technology.Funding was obained from MATCH (Multidisciplinary Assessment of Technologies Centre for Healthcare)
An analysis of the crossover between local and massive separation on airfoils
Massive separation on airfoils operating at high Reynolds number is an important problem to the aerodynamicist, since its onset generally determines the limiting performance of an airfoil, and it can lead to serious problems related to aircraft control as well as turbomachinery operation. The phenomenon of crossover between local separation and massive separation on realistic airfoil geometries induced by airfoil thickness is investigated for low speed (incompressible) flow. The problem is studied both for the asymptotic limit of infinite Reynolds number using triple-deck theory, and for finite Reynolds number using interacting boundary-layer theory. Numerical results are presented which follow the evolution of the flow as it develops from a mildly separated state to one dominated by the massively separated flow structure as the thickness of the airfoil geometry is systematically increased. The effect of turbulence upon the evolution of the flow is considered, and the impact is significant, with the principal effect being the suppression of the onset of separation. Finally, the effect of surface suction and injection for boundary-layer control is considered. The approach which was developed provides a valuable tool for the analysis of boundary-layer separation up to and beyond stall. Another important conclusion is that interacting boundary-layer theory provides an efficient tool for the analysis of the effect of turbulence and boundary-layer control upon separated vicsous flow
Securing a Quantum Key Distribution Network Using Secret Sharing
We present a simple new technique to secure quantum key distribution relay
networks using secret sharing. Previous techniques have relied on creating
distinct physical paths in order to create the shares. We show, however, how
this can be achieved on a single physical path by creating distinct logical
channels. The technique utilizes a random 'drop-out' scheme to ensure that an
attacker must compromise all of the relays on the channel in order to access
the key
Extending the Reach of QKD Using Relays
One of the obstacles to deployment of QKD solutions has been the distance
limitation. Solutions using relays have been proposed but these rely on
link-by-link key establishment. We present a new technique to extend the
distance of a quantum key distribution channel using an active relay. Each
relay acts as an intercept/resend device and allows the establishment of an
end-to-end key. It has been argued that such relays cannot be used to extend
the distance, but we show that with a suitable adaptation of the protocol the
effective key distribution distance can be increased
Temperature dependence of the average electron-hole pair creation energy in Al0.8Ga0.2As
The temperature dependence of the average energy consumed in the creation of an electron-hole pair in the wide bandgap compound semiconductor Al 0.8Ga0.2As is reported following X-ray measurements made using an Al0.8Ga0.2As photodiode diode coupled to a low-noise charge-sensitive preamplifier operating in spectroscopic photon counting mode. The temperature dependence is reported over the range of 261 K-342 K and is found to be best represented by the equation ε AlGaAs 7.327-0.0077 T, where εAlGaAs is the average electron-hole pair creation energy in eV and T is the temperature in K. © 2013 © 2013 Author(s)
Grassmann phase space theory for fermions
A phase space theory for fermions has been developed using Grassmann phase space variables which can be used in numerical calculations for cold Fermi gases and for large fermion numbers. Numerical calculations are feasible because Grassmann stochastic variables at later times are related linearly to such variables at earlier times via c-number stochastic quantities. A Grassmann field version has been developed making large fermion number applications possible. Applications are shown for few mode and field theory cases
Optical orbital angular momentum
We present a brief introduction to the orbital angular momentum of light, the subject of our theme issue and, in particular, to the developments in the 13 years following the founding paper by Allen et al. (Allen et al. 1992 Phys. Rev. A 45, 8185 (doi:10.1103/PhysRevA.45.8185)). The papers by our invited authors serve to bring the field up to date and suggest where developments may take us next
- …