8,810 research outputs found
A Feature-Augmented Grammar for Automated Media Production
The IST Polymnia project is creating a fully automated system for personalised video generation, including content creation, selection and composition. This paper presents a linguistically motivated solution using context-free feature-augmented grammar rules to describe editing tasks and hence automate video editing. The solution is media and application independent
Bonding machine for forming a solar array strip
A machine is described for attaching solar cells to a flexable substrate on which printed circuitry has been deposited. The strip is fed through: (1) a station in which solar cells are elevated into engagement with solder pads for the printed circuitry and thereafter heated by an infrared lamp; (2) a station at which flux and solder residue is removed; (3) a station at which electrical performance of the soldered cells is determined; (4) a station at which an encapsulating resin is deposited on the cells; (5) a station at which the encapsulated solar cells are examined for electrical performance; and (6) a final station at which the resulting array is wound on a takeup drum
The Stability of an Isotropic Cosmological Singularity in Higher-Order Gravity
We study the stability of the isotropic vacuum Friedmann universe in gravity
theories with higher-order curvature terms of the form
added to the Einstein-Hilbert Lagrangian of general relativity on approach to
an initial cosmological singularity. Earlier, we had shown that, when ,
a special isotropic vacuum solution exists which behaves like the
radiation-dominated Friedmann universe and is stable to anisotropic and small
inhomogeneous perturbations of scalar, vector and tensor type. This is
completely different to the situation that holds in general relativity, where
an isotropic initial cosmological singularity is unstable in vacuum and under a
wide range of non-vacuum conditions. We show that when , although a
special isotropic vacuum solution found by Clifton and Barrow always exists, it
is no longer stable when the initial singularity is approached. We find the
particular stability conditions under the influence of tensor, vector, and
scalar perturbations for general for both solution branches. On approach to
the initial singularity, the isotropic vacuum solution with scale factor
is found to be stable to tensor perturbations for and stable to vector perturbations for , but is
unstable as otherwise. The solution with scale factor
is not relevant to the case of an initial singularity for
and is unstable as for all for each type of perturbation.Comment: 25 page
Cosmogenic radionuclides on LDEF: An unexpected Be-10 result
Following the discovery of the atmospheric derived cosmogenic radionuclide Be-7 on the Long Duration Exposure Facility (LDEF), a search began for other known nuclides produced by similar mechanisms. None of the others have the narrow gamma-ray line emission of Be-7 decay which enabled its rapid detection and quantification. A search for Be-10 atoms on LDEF clamp plates using accelerator mass spectrometry is described. An unexpected result was obtained
Hysterectomy, endometrial ablation, and levonorgestrel releasing intrauterine system (Mirena) for treatment of heavy menstrual bleeding : cost effectiveness analysis
Peer reviewedPublisher PD
The occupational role of the lay health trainer in England: a review of practice
Health Trainers constitute an emergent occupational group in the Public Health system in England with the key purpose to reduce health inequalities by helping or ‘nudging’ people in local communities to adopt healthier lifestyles. Whilst primarily supplying health-related information and support regarding smoking cessation, diet, alcohol, physical activity and mental wellbeing issues, the role also requires awareness of, and sensitivity toward the specific needs of local communities. This literature review charts current research on the occupational context of the Health Trainer role since its implementation in the English Public Health system. It provides a critical examination of current literature whilst highlighting the theoretical basis of Health Trainers’ roles, the potential boundary-crossing nature of their work, along with professional development issues
Hysterectomy, endometrial destruction, and levonorgestrel releasing intrauterine system (Mirena) for heavy menstrual bleeding : systematic review and meta-analysis of data from individual patients
Peer reviewedPublisher PD
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