2,402 research outputs found
Secure Vehicular Communication Systems: Implementation, Performance, and Research Challenges
Vehicular Communication (VC) systems are on the verge of practical
deployment. Nonetheless, their security and privacy protection is one of the
problems that have been addressed only recently. In order to show the
feasibility of secure VC, certain implementations are required. In [1] we
discuss the design of a VC security system that has emerged as a result of the
European SeVeCom project. In this second paper, we discuss various issues
related to the implementation and deployment aspects of secure VC systems.
Moreover, we provide an outlook on open security research issues that will
arise as VC systems develop from today's simple prototypes to full-fledged
systems
Electronic and magnetic properties of GaMnAs: Annealing effects
The effect of short-time and long-time annealing at 250C on the conductivity,
hole density, and Curie temperature of GaMnAs single layers and GaMnAs/InGaMnAs
heterostructures is studied by in-situ conductivity measurements as well as
Raman and SQUID measurements before and after annealing. Whereas the
conductivity monotonously increases with increasing annealing time, the hole
density and the Curie temperature show a saturation after annealing for 30
minutes. The incorporation of thin InGaMnAs layers drastically enhances the
Curie temperature of the GaMnAs layers.Comment: 4 pages, 6 figures, submitted to Physica
Investigating well-being, work limitations and preferences for self-management education and peer support among younger people with hip and knee osteoarthritis: protocol for a cross-sectional study
Introduction: Osteoarthritis (OA) has traditionally been considered a condition of older age. However, younger people are also affected by hip and knee OA, often as a result of sporting and work-related injuries. As OA studies have generally focused on older individuals, little is known about the experience of younger adults with hip or knee OA who can face a distinct set of pressures including work responsibilities and parenting roles. This study aims to investigate well-being and work participation among younger people with hip or knee OA, as well as preferences for OA education and support.Methods and analysis: 200 people aged 20–55 years with a diagnosis of hip and/or knee OA will be recruited for this cross-sectional study. Participants will be recruited from three major public hospitals in the state of Victoria, Australia following screening of orthopaedic outpatient clinic lists and referrals, and through community-based advertisements. A study questionnaire will be mailed to all participants and written informed consent obtained. Validated measures of Health-Related Quality of Life (HRQoL), health status, psychological distress and work limitations will be used. Information on health services use will be collected, in addition to information on the perceived utility and accessibility of a range of existing and proposed education and peer support models. HRQoL data will be compared with Australian population norms using independent t tests, and associations between HRQoL, health status, psychological distress, work limitations and demographic factors will be evaluated using univariate and multivariate analyses. Data on the perceived utility and accessibility of education and peer support models will be analysed descriptively. Ethics and dissemination: Ethics approval for the study has been obtained. The study findings will be submitted to peer-reviewed journals and arthritis consumer organisations for broader dissemination, and presented at national and international scientific meetings.</div
Effect of annealing on the depth profile of hole concentration in (Ga,Mn)As
The effect of annealing at 250 C on the carrier depth profile, Mn
distribution, electrical conductivity, and Curie temperature of (Ga,Mn)As
layers with thicknesses > 200 nm, grown by molecular-beam epitaxy at low
temperatures, is studied by a variety of analytical methods. The vertical
gradient in hole concentration, revealed by electrochemical capacitance-voltage
profiling, is shown to play a key role in the understanding of conductivity and
magnetization data. The gradient, basically already present in as-grown
samples, is strongly influenced by post-growth annealing. From secondary ion
mass spectroscopy it can be concluded that, at least in thick layers, the
change in carrier depth profile and thus in conductivity is not primarily due
to out-diffusion of Mn interstitials during annealing. Two alternative possible
models are discussed.Comment: 8 pages, 8 figures, to appear in Phys. Rev.
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