1,107 research outputs found
A model for large-scale volcanic plumes on Io: Implications for eruption rates and interactions between magmas and near-surface volatiles.
Volcanic plumes deposit magmatic pyroclasts and SO2 frost on the surface of Io. We model the plume activity detected by Galileo at the Pillan and Pele sites from 1996 to 1997 assuming that magmatic eruptions incorporate liquid SO2 from near-surface aquifers intersecting the conduit system and that the SO2 eventually forms a solid condensate on the ground. The temperature and pressure at which deposition of solid SO2 commences in the Ionian environment and the radial distance from the volcanic vent at which this process appears to occur on the surface are used together with observed vertical heights of plumes to constrain eruption conditions. The temperature, pressure, and density of the gas–magma mixtures are related to distance from the vent using continuity and conservation of energy. Similar eruption mass fluxes of order 5x10^7 kg s^1 are found for both the Pillan and the Pele plumes. The Pele plume requires a larger amount of incorporated SO2 (29–34 mass %) than the Pillan plume (up to 6 mass%). Implied vent diameters range from c. 90m at Pillan to c. 500 m at Pele. The radial extents of the optically dense, isothermal, incandescent parts of the eruption plumes immediately above the vents are 100 m at Pillan and 1300 m at Pele. Gas pressures in the vents are 20 kPa at Pillan and 2 kPa at Pele and the eruption conditions appear to be supersonic in both cases, though only just so at Pele
Measuring Positions of Objects using Two or More Cameras
An improved method of computing positions of objects from digitized images acquired by two or more cameras (see figure) has been developed for use in tracking debris shed by a spacecraft during and shortly after launch. The method is also readily adaptable to such applications as (1) tracking moving and possibly interacting objects in other settings in order to determine causes of accidents and (2) measuring positions of stationary objects, as in surveying. Images acquired by cameras fixed to the ground and/or cameras mounted on tracking telescopes can be used in this method. In this method, processing of image data starts with creation of detailed computer- aided design (CAD) models of the objects to be tracked. By rotating, translating, resizing, and overlaying the models with digitized camera images, parameters that characterize the position and orientation of the camera can be determined. The final position error depends on how well the centroids of the objects in the images are measured; how accurately the centroids are interpolated for synchronization of cameras; and how effectively matches are made to determine rotation, scaling, and translation parameters. The method involves use of the perspective camera model (also denoted the point camera model), which is one of several mathematical models developed over the years to represent the relationships between external coordinates of objects and the coordinates of the objects as they appear on the image plane in a camera. The method also involves extensive use of the affine camera model, in which the distance from the camera to an object (or to a small feature on an object) is assumed to be much greater than the size of the object (or feature), resulting in a truly two-dimensional image. The affine camera model does not require advance knowledge of the positions and orientations of the cameras. This is because ultimately, positions and orientations of the cameras and of all objects are computed in a coordinate system attached to one object as defined in its CAD model
“Hearing the Need” A study of the implementation of Social and Emotional Learning (SEL) Programmes in nine schools in the West of Ireland.
In recent years there has been a growing interest in the topic of wellbeing. This has been a societal trend but also a trend in education. Primary schools in Ireland had started, from circa 2014, to introduce Social and Emotional Learning (SEL) programmes into their curricula with a view to enhancing the wellbeing of their pupils. These programmes were neither mandated nor facilitated by the DES. Their introduction was a school-based decision.
This narrative inquiry explored the stories of principals and teachers in nine primary schools in County Galway relating to the introduction of SEL programmes in their various schools. The stories recounted described why the participants considered this action was necessary, how the decision was made, what the outcomes were for teachers in classrooms and how they said they could sustain these new practices. Drawing on sociological scholarship and the ethics of care, the work considers public policy and practitioner actions as recounted by teachers and principals and the increasing tension between them at their interface in schools.
A picture emerges from the collected narratives of a growing anxiety among young children that schools feel compelled to respond to. Caring practices are central to the work that is transacted in schools and a driver of decision-making. However, in the context of a new managerialism in education, teachers are being hampered in their care practices by what they described as an avalanche of new initiatives. They speak about being overstretched and failing to address their caring priorities in a meaningful way.
In presenting a clear picture of the tension between care and managerialism, the research highlights the dilemma of schools and the necessity to validate the daily caring practices enacted in classrooms and in schools
University-Community Engagement and Public Relations Education: A Replication and Extension of Service-Learning Assessment in the Public Relations Campaigns Course
This study replicated and extended Werder and Strand’s 2011 research by framing service-learning within the larger context of a university’s overall community engagement strategy and by including alumni within the survey population. The findings supported a general service-learning assessment instrument measuring students’ perceptions of their development of key public relations skills, along with citizenship and social responsibility mindsets, as a result of their participation in community-based projects in a public relations capstone course. While the results, overall, were consistent with Werder and Strand's study, there were notable differences. For example, this study found that there were no statistically significant difference in means— by gender, time, and client type—for most variables. However, alumni who had worked for businesses in a town designated as an official community engagement partner had higher mean scores on three items: community involvement, strategic planning skills, and ability to work with others. The findings contribute to the collective understanding of community engagement, public relations education and practice, and the lasting impact of service-learning on students post-graduation. Whether service-learning values such as citizenship and social responsibility "stick" after graduation is a key consideration for any profession, but especially for public relations
Same Difference: Detecting Collusion by Finding Unusual Shared Elements
Pam Green, Peter Lane, Austen Rainer, Sven-Bodo Scholz, Steve Bennett, ‘Same Difference: Detecting Collusion by Finding Unusual Shared Elements’, paper presented at the 5th International Plagiarism Conference, Sage Gateshead, Newcastle, UK, 17-18 July, 2012.Many academic staff will recognise that unusual shared elements in student submissions trigger suspicion of inappropriate collusion. These elements may be odd phrases, strange constructs, peculiar layout, or spelling mistakes. In this paper we review twenty-nine approaches to source-code plagiarism detection, showing that the majority focus on overall file similarity, and not on unusual shared elements, and that none directly measure these elements. We describe an approach to detecting similarity between files which focuses on these unusual similarities. The approach is token-based and therefore largely language independent, and is tested on a set of student assignments, each one consisting of a mix of programming languages. We also introduce a technique for visualising one document in relation to another in the context of the group. This visualisation separates code which is unique to the document, that shared by just the two files, code shared by small groups, and uninteresting areas of the file.Peer reviewe
Hopf monads on monoidal categories
We define Hopf monads on an arbitrary monoidal category, extending the
definition given previously for monoidal categories with duals. A Hopf monad is
a bimonad (or opmonoidal monad) whose fusion operators are invertible. This
definition can be formulated in terms of Hopf adjunctions, which are comonoidal
adjunctions with an invertibility condition. On a monoidal category with
internal Homs, a Hopf monad is a bimonad admitting a left and a right antipode.
Hopf monads generalize Hopf algebras to the non-braided setting. They also
generalize Hopf algebroids (which are linear Hopf monads on a category of
bimodules admitting a right adjoint). We show that any finite tensor category
is the category of finite-dimensional modules over a Hopf algebroid. Any Hopf
algebra in the center of a monoidal category C gives rise to a Hopf monad on C.
The Hopf monads so obtained are exactly the augmented Hopf monads. More
generally if a Hopf monad T is a retract of a Hopf monad P, then P is a cross
product of T by a Hopf algebra of the center of the category of T-modules
(generalizing the Radford-Majid bosonization of Hopf algebras). We show that
the comonoidal comonad of a Hopf adjunction is canonically represented by a
cocommutative central coalgebra. As a corollary, we obtain an extension of
Sweedler's Hopf module decomposition theorem to Hopf monads (in fact to the
weaker notion of pre-Hopf monad).Comment: 45 page
Resonant and Non-Resonant Effects in Photon-Technipion Production at Lepton Colliders
Lepton collider experiments can search for light technipions in final states
made striking by the presence of an energetic photon: e+e- \to
\photon\technipion. To date, searches have focused on either production
through anomalous coupling of the technipions to electroweak gauge bosons or on
production through a technivector meson (\technirho, \techniomega) resonance.
This paper creates a combined framework in which both contributions are
included. This will allow stronger and more accurate limits on technipion
production to be set using existing data from LEP or future data from a
higher-energy linear collider. We provide explicit formulas and sample
calculations (analytic and Pythia) in the framework of the Technicolor Straw
Man Model, a model that includes light technihadrons.Comment: 11 pages, including title page, 3 figures; version 2: references
adde
Sulfa Resistance in Mouse-Derived Pneumocystis carinii
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/74674/1/j.1550-7408.1996.tb04975.x.pd
Development of an operational, risk-based approach to surface water flood forecasting
Surface water flooding occurs regularly across England and Wales, especially during the summer months. It is widely acknowledged that surface water flooding presents a particular challenge to forecasters because of the difficulties inherent in forecasting intense localised rainfall and the highly complex runoff and drainage processes which operate at the surface, particularly in urban areas.
The Flood Forecasting Centre (FFC) has a responsibility to provide guidance on the risk of surface water flooding to Category 1 and 2 responders across England and Wales. Consequently, there is the requirement for improved methods for forecasting surface water flood risk and the FFC is currently involved in developing and trialling a novel surface water flood forecasting system, the Surface Water Flooding Hazard Impact Model (SWF HIM).
The SWF HIM offers significant advances over existing surface water flood forecasting methods used by the FFC, including provision of a risk-based approach. The SWF HIM links probabilistic runoff forecasts from the Centre for Ecology & Hydrology’s Grid-to-Grid model with a library of pre-calculated surface water impact information compiled by the Health and Safety Laboratory. These probabilistic runoff forecasts are combined with impact information to provide a forecast of surface water flood risk at a 1km2 resolution across England and Wales.
This presentation outlines the methodology together with some initial results from the trial. The work has been undertaken as part of the UK’s Natural Hazards Partnership (NHP) and also benefits from the close working relationship between the Environment Agency and the Met Office through the FFC
To GP or not to GP: a natural experiment in children triaged to see a GP in a tertiary paediatric emergency department (ED)
Objective: To evaluate the impact of integrating a general practitioner (GP) into a tertiary paediatric emergency department (ED) on admissions, waiting times and antibiotic prescriptions. Design: Retrospective cohort study. Setting: Alder Hey Children’s NHS Foundation Trust, a tertiary paediatric hospital in Liverpool, UK. Participants: From October 2014, a GP was colocated within the ED, from 14:00 to 22:00 hours, 7 days a week. Children triaged green on the Manchester Triage System without any comorbidities were classed as ‘GP appropriate’. The natural experiment compared patients triaged as ‘GP appropriate’ and able to be seen by a GP between 14:00 and 22:00 hours (GP group) to patients triaged as ‘GP appropriate’ seen outside of the hours when a GP was available (ED group). Intention-to-treat (ITT) analysis was used to assess the main outcomes. Results: 5223 patients were designated as ‘GP appropriate’—18.2% of the total attendances to the ED over the study period. There were 2821 (54%) in the GP group and 2402 (46%) in the ED group. The median duration of stay in the ED was 94 min (IQR 63–141) for the GP group compared with 113 min (IQR 70–167) for the ED group (p<0.0005). Using the ITT analysis equivalent, we demonstrated that the GP group were less likely to: be admitted to hospital (2.2% vs 6.5%, OR 0.32, 95% CI 0.24 to 0.44), wait longer than 4 hours (2.3% vs 5.1%, OR 0.45, 95% CI 0.33 to 0.61) or leave before being seen (3.1% vs 5.7%, OR 0.53, 95% CI 0.41 to 0.70), but more likely to receive antibiotics (26.1% vs 20.5%, OR 1.37, 95% CI 1.10 to 1.56). Sensitivity analyses yielded similar results. Conclusions: Introducing a GP to a paediatric ED service can significantly reduce waiting times and admissions, but may lead to more antibiotic prescribing. This study demonstrates a novel, potentially more efficient ED care pathway in the current context of rising demand for children’s emergency services
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