Mesospheric observations with the EISCAT UHF radar during polar cap absorption events: <br>3. Comparison with simultaneous EISCAT VHF measurements

International audienceMesospheric observations were obtained by the EISCAT UHF and VHF radars during the solar proton event of March 1990. We present the first comparison of incoherent-scatter spectral measurements from the middle mesosphere using simultaneous, co-located observations by the two radars. VHF spectra observed with a vertical antenna were found to be significantly narrower than model predictions, in agreement with earlier UHF results. For antenna pointing directions that were significantly away from the vertical, the wider VHF radar beam gave rise to broadening of the observed spectra due to vertical shears in the horizontal wind. In this configuration, UHF spectral measurements were found to be more suitable for aeronomical applications. Both radar systems provide consistent and reliable estimates of the neutral wind. Spectral results using both the multipulse and pulse-to-pulse schemes were intercompared and their suitability for application to combined mesosphere ? lower thermosphere studies investigated

Doped Ceria Catalysts for NOx Storage and Reduction

The new Euro 7 protocol, proposed by the Commission on 26th October 2022, concerning emissions of leanburn engines, presents a need for further optimisation of existing after-treatment technologies. It reveals a 35% reduction to the NOx emission limit for cars and vans, compared to Euro 6 . A well-known technology employed to reduce NOx to clean emissions in light-duty vehicles is the Lean NOx Trap (LNT). LNTs employ catalysts consisting of PGMs supported on ceria (CeO2) or other mixed oxides. Ceria’s redox property makes it an attractive selection, as well as its ability to store NOx at low temp (<300 ̊C), especially when Pt is present. Storage properties of ceria can be further enhanced by doping. Dopants reportedly allow ceria to function better at low temperature (<300 ̊C), and to reduce the PGM loading required to achieve the same conversion efficiencies. The RE metals Sm, Pr and Nd have been employed as dopants on CeO2 for LNT applications to increase surface oxygen content, oxygen vacancies, defect densities, and cause changes to the Pt-ceria interaction. These structural changes can allow for higher NSC during lean operation and enhanced activation during rich purge. Sm, Pr and Nd doped catalysts (10 wt.%) were synthesised on a range of ceria based catalysts with different Pt loadings (0-1 wt.%). Morphological changes observed through dopant addition has been investigated and related to catalytic performance increases.

Post-Disaster Housing Reconstruction in Sri Lanka: What Methodology?

Research methodology is the procedural framework within which the research is conducted. This includes the overall approach to a problem that could be put into practice in a research process, from the theoretical underpinning to the collection and analysis of data. Choice of methodology depends on the primary drivers: topic to be researched and the specific research questions. Hence, methodological perspectives of managing stakeholder expectations of PDHR context are composed of research philosophies, research strategy, research design, and research techniques. This research belonged to social constructivism or interpretivism within a philosophical continuum. The nature of the study was more toward subjectivism where human behavior favored voluntary stance. Ontological, methodological, epistemological, and axiological positioning carried the characteristics of idealism, ideographic, anti-positivism, and value laden, respectively. Data collection comprises two phases, preliminary and secondary. Exploratory interviews with construction experts in the United Kingdom and Sri Lanka were carried out to refine the interview questions and identify the case studies. Case study interviews during the secondary phase took place in Sri Lanka. Data collected at the preliminary stage were used to assess the attributes of power, legitimacy/proximity, and urgency of stakeholders to the project using Stakeholder Circle™ software. Moreover, the data collected at secondary phase via case studies will be analyzed with NVivo 8. This article aims to discuss these methodological underpinnings in detail applied in a post-disaster housing reconstruction context in Sri Lanka

Identification of clouds and aurorae in optical data images

In this paper we present an automatic image recognition technique used to identify clouds and aurorae in digital images, taken with a CCD all-sky imager. The image recognition algorithm uses image segmentation to generate a binary block object image. Object analysis is then performed on the binary block image, the results of which are used to assess whether clouds, aurorae and stars are present in the original image. The need for such an algorithm arises because the optical study of particle precipitation into the Earth's atmosphere by the Ionosphere and Radio Propagation Group at Lancaster generates vast data-sets, over 25 000 images/year, making manual classification of all the images impractical

Portability and networked learning environments

Abstract The portability of educational software is defined as the likelihood of software usage, with or without adaptation, in an educational environment different from that for which it was originally designed and produced. Barriers and research relevant to the portability of electronic learning resources are discussed and organised into a portability-limiting factors model. With the increase in number and scope of networked learning environments, portability issues take on a new dimension. Using electronic (study) books as an example, the portability problem space of networked learning environments is explored

Learning from peer feedback on student-generated multiple choice questions: Views of introductory physics students

PeerWise is an online application where students are encouraged to generate a bank of multiple choice questions for their classmates to answer. After answering a question, students can provide feedback to the question author about the quality of the question and the question author can respond to this. Student use of, and attitudes to, this online community within PeerWise was investigated in two large first year undergraduate physics courses, across three academic years, to explore how students interact with the system and the extent to which they believe PeerWise to be useful to their learning. Most students recognized that there is value in engaging with PeerWise, and many students engaged deeply with the system, thinking critically about the quality of their submissions and reflecting on feedback provided to them. Students also valued the breadth of topics and level of difficulty offered by the questions, recognized the revision benefits afforded by the resource, and were often willing to contribute to the community by providing additional explanations and engaging in discussion

Numerical Evaluation of P-Multigrid Method for the Solution of Discontinuous Galerkin Discretizations of Diffusive Equations

This paper describes numerical experiments with P-multigrid to corroborate analysis, validate the present implementation, and to examine issues that arise in the implementations of the various combinations of relaxation schemes, discretizations and P-multigrid methods. The two approaches to implement P-multigrid presented here are equivalent for most high-order discretization methods such as spectral element, SUPG, and discontinuous Galerkin applied to advection; however it is discovered that the approach that mimics the common geometric multigrid implementation is less robust, and frequently unstable when applied to discontinuous Galerkin discretizations of di usion. Gauss-Seidel relaxation converges 40% faster than block Jacobi, as predicted by analysis; however, the implementation of Gauss-Seidel is considerably more expensive that one would expect because gradients in most neighboring elements must be updated. A compromise quasi Gauss-Seidel relaxation method that evaluates the gradient in each element twice per iteration converges at rates similar to those predicted for true Gauss-Seidel

Pilot study to evaluate the use of remote patient monitoring to guide the timing of valve intervention in patients with severe asymptomatic aortic stenosis (APRAISE-AS): study protocol for a randomised controlled trial delivered in two tertiary cardiac centres in the UK.

Aortic stenosis (AS) is common affecting >13% of adults over the age of 75 years. In people who develop symptoms, without valve replacement, prognosis is dismal with mortality as high as 50% at 1 year. In asymptomatic patients, the timing of valve intervention is less well defined and a strategy of watchful waiting is recommended. Many, however, may develop symptoms and attribute this to age related decline, rather than worsening AS. Timely intervention in asymptomatic severe AS is critical, since delayed intervention often results in poor outcomes. Proactive surveillance of symptoms, quality of life and functional capacity should enable timely identification of people who will benefit from aortic valve replacement. There are no data however, to support the clinical and cost effectiveness of such an approach in a healthcare setting in the UK. The aim of this pilot trial is to test the feasibility of a full-scale randomised controlled trial (RCT) to determine the utility of proactive surveillance in people with asymptomatic severe AS to guide the timing of intervention. APRAISE-AS is a multi-centre, non-blinded, two-arm, parallel group randomised controlled trial of up to 66 participants aged >18 years with asymptomatic severe AS. Participants will be randomised to either standard care or standard care supplemented with the APRAISE-AS intervention. Primary outcomes will capture; adherence to and participant acceptability of the intervention, recruitment and retention rates, and completeness of data collection. The findings will be used to inform the sample size and most appropriate outcome measure(s) for a full-scale RCT and health economic evaluation. Ethical approval was granted by the Black Country REC, reference: 22/WM/0214. Results will be submitted for publication in peer-reviewed journals and disseminated at local, regional and national meetings where appropriate. ISRCTN19413194 registered on 14.07.2023. [Abstract copyright: © Author(s) (or their employer(s)) 2024. Re-use permitted under CC BY. Published by BMJ.

Perspectives on Enabling Education for Indigenous Students at Three Comprehensive Universities in Regional Australia

Daniels, CR ORCiD: 0000-0002-0672-0450Indigenous students, particularly those from regional and remote areas, are under-represented in both higher education and vocational education in Australia. Enabling programs seek to address this under-representation. They offer pathways to higher education, are important in lifting participation rates and potentially encourage mobility between the sectors. However, strategic development of enabling programs is based on little evidence about student or staff experiences. This chapter presents a qualitative research project underpinned by the strengths-based approach of conscientisation, exploring how Indigenous learning journeys via enabling programs can respect and grow cultural identity, while simultaneously developing study skills. The research considered interpretations of ‘success’ from the perspectives of students and teachers participating in enabling courses. The research found that enabling programs were an ‘important’ and ‘exciting journey’ for students that brought about transformation of the inner self through the building of ‘resilience’, ‘strength’, ‘confidence’, ‘self-esteem’, ‘self-worth’, ‘cultural understanding’ and ‘identity’. Success was experienced across multiple dimensions of students’ lived experience including ‘cultural identity’, ‘voice’, self-realisation, self-acceptance and ‘pride’. Staff suggested that enabling programs imparted an ‘underlying layer’ of skills. Recognition of Indigenous people as ‘yarners’ and ‘story tellers’, along with ways of incorporating ‘both-ways’ methodologies, need to be considered when developing the curriculum. This chapter reports on research which will be used to inform the development of a best-practice framework for Indigenous education enabling programs in Australia, particularly in regional and comprehensive education settings