1,191 research outputs found
Towards an institutional PLE
PLEs in their broader sense (the ad-hoc, serendipitous and potentially chaotic set of tools that learners bring to their learning) are increasingly important for learners in the context of formal study. In this paper we outline the approach that we are taking at the University of Southampton in redesigning our teaching and learning infrastructure into an Institutional PLE. We do not see this term as an oxymoron. We define an Institutional PLE as an environment that provides a personalised interface to University data and services and at the same time exposes that data and services to a student’s personal tools. Our goal is to provide a digital platform that can cope with an evolving learning and teaching environment, as well as support the social and community aspects of the institution
Automatic exposure control for space sequential camera
The final report for the automatic exposure control study for space sequential cameras, for the NASA Johnson Space Center is presented. The material is shown in the same sequence that the work was performed. The purpose of the automatic exposure control is to automatically control the lens iris as well as the camera shutter so that the subject is properly exposed on the film. A study of design approaches is presented. Analysis of the light range of the spectrum covered indicates that the practical range would be from approximately 20 to 6,000 foot-lamberts, or about nine f-stops. Observation of film available from space flights shows that optimum scene illumination is apparently not present in vehicle interior photography as well as in vehicle-to-vehicle situations. The evaluation test procedure for a breadboard, and the results, which provided information for the design of a brassboard are given
Automatic Exposure Iris Control (AEIC) for data acquisition camera
A lens design capable of operating over a total range of f/1.4 to f/11.0 with through the lens light sensing is presented along with a system which compensates for ASA film speeds as well as shutter openings. The space shuttle camera system package is designed so that it can be assembled on the existing 16 mm DAC with a minimum of alteration to the camera
Solid Waste Management and the Need for Effective Public Participation
Recent changes in technical requirements for landfill design, mandated by the U.S. Environmental Protection Agency, have led to closing the majority of solid waste landfills in the United States. Efforts to site new landfills have elicited widespread opposition. Based on eight case studies in Alabama, we identify three themes behind this opposition: threats to quality of life, potentially harmful economic impacts, and frustration over representational issues in the process involved in selecting the proposed solid waste facility. These concerns mirror much of the literature on public opposition to landfills and other facilities which pose similar threats to the environment and public health. The incidence of public opposition raises the question of why, when the technical regulations affecting solid waste landfills were updated, no parallel modification of the permit process for such facilities was initiated. In light of concerns expressed in our case studies, we identify a set of suggested modifications that would allow for greater public participation in the siting and permitting process
WSO/UV: World Space Observatory/Ultraviolet
We summarize the capabilities of the World Space Observatory (UV) Project
(WSO/UV). An example of the importance of this project (with a planned launch
date of 2007/8) for the study of Classical Novae is given.Comment: 4 pages, To appear in the proceeedings of the "Classical Nova
Explosions" conference, eds. M. Hernanz and J. Jose, AI
Host range, symbiotic effectiveness and nodulation competitiveness of some indigenous cowpea bradyrhizobia isolates from the transitional savanna zone of Ghana
To identify indigenous rhizobia with potential as inoculants for increasing cowpea (Vigna unguiculata) yields, we have assessed the host range, symbiotic effectiveness and competitiveness for noduleoccupancy among five (AII-2-1, AII-5-2, AI-4-3, AII-3-4 and BIII-2-2) indigenous cowpea bradyrhizobia isolates from the transitional savanna zone of Ghana. ERIC-PCR DNA fingerprinting patterns were used to identify the isolates occupying nodules. All the isolates nodulated cowpea, groundnut (Arachis hypogeae) and mungbean (Vigna radiata), but only AII-2-1, AII-3-4 and BIII-2-2 nodulated soybean (Glycine max). Apart from cowpea where all the isolates were effective, there were significant differences in the symbiotic effectiveness of the isolates on the other host legumes. Out of a total of about 250 cowpea nodules that were screened for each inoculum-mix, isolate AII-5-2 was the most competitive for nodule occupancy whilst AII-3-4 was the least. Isolate AII-5-2 occupied 71% of the nodules in an inoculum-mix consisting of equal proportions of AII-2-1, AII-5-2 and AI-4-3 (a 3-isolatemix) and 60% of nodules in an inoculum-mix consisting of equal proportions of all the five isolates (a 5- isolate-mix). Therefore, among the isolates tested, AII-5-2 has the best potential for use as inoculant formaximizing cowpea yield in N2- deficient agro-ecological zones of Ghana
Neutron imaging and modelling inclined vortex driven thin films.
The vortex fluidic device (VFD) is a thin film microfluidic platform which has a wide range of applications in synthesis and other areas of science, and it is important to understand the nature of the thin film of liquid in its inclined rapidly rotating tube. Neutron imaging has been used to determine the thickness of the film in a quartz tube with its shape modelled mathematically, showing good agreement between the model and experiments. The resultant equations are useful for studying VFD mediated processing in general, for which the optimal tilt angle of the tube is typically 45°. This includes its utility for the intelligent scale-up of organic syntheses, as demonstrated in the present study by the scaling up of an imine and amide synthesis to >1 g/min
Abell 43: Longest period Planetary Nebula Nucleus variable
Based on 24h high speed photometry of the hybrid PG 1159 star Abell 43, we
have detected 6 sighificant pulsations with periods between 2380 s and 6075 s.
A short (4h) run on the almost spectroscopic twin NGC 7094 central star
resulted in detection of 3 low amplitude pulsations with periods between 2000 s
and 5000 s. The results are close to predictions for g-mode pulsations driven
by the kappa-mechanism induced by the partial ionization of carbon and oxygen.Comment: 5 pages, 5 figures, to be published in Astronomy and Astrophysic
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