2,175 research outputs found

    Variation of turbulent burning rate of methane, methanol, and iso-octane air mixtures with equivalence ratio at elevated pressure

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    Turbulent burning velocities for premixed methane, methanol, and iso-octane/air mixtures have been experimentally determined for an rms turbulent velocity of 2 m/s and pressure of 0.5 MPa for a wide range of equivalence ratios. Turbulent burning velocity data were derived using high-speed schlieren photography and transient pressure recording; measurements were processed to yield a turbulent mass rate burning velocity, utr. The consistency between the values derived using the two techniques, for all fuels for both fuel-lean and fuel-rich mixtures, was good. Laminar burning measurements were made at the same pressure, temperature, and equivalence ratios as the turbulent cases and laminar burning velocities and Markstein numbers were determined. The equivalence ratio (φ) for peak turbulent burning velocity proved not always coincident with that for laminar burning velocity for the same fuel; for isooctane, the turbulent burning velocity unexpectedly remained high over the range φ = 1 to 2. The ratio of turbulent to laminar burning velocity proved remarkably high for very rich iso-octane/air and lean methane/air mixtures

    Using video and multimodal classroom interaction analysis to investigate how information, misinformation, and disinformation influence pedagogy

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    Misinformation is accidentally wrong and disinformation is deliberately incorrect (i.e., deception). This paper uses the Pedagogy Analysis Framework (PAF) to investigate how information, misinformation, and disinformation influence classroom pedagogy. 95 people participated (i.e., one lesson with 7-year-olds, another with 10-year-olds, and three with a class of 13-year-olds). We used four video-based methods (lesson video analysis, teacher verbal protocols, pupil group verbal protocols, and teacher interviews). 35 hours of video data (recorded 2013-2020) were analysed using Grounded Theory Methods by the researchers, the class teachers, and groups of pupils (three girls and three boys). The methodology was Straussian Grounded Theory. We present how often participants used information, misinformation, and disinformation. We illustrate how the PAF helps understand and explain information, misinformation, and disinformation in the classroom by analysing video data transcripts. In addition, we discuss participant perceptions of the status of information; overlapping information, misinformation, and disinformation; and information communication difficulties

    Teachers' perspectives on the relationship between secondary school departments of science and religious education: Independence or mutual enrichment?

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    There is a gap in the research on the relationship between secondary school subject departments, particularly where, as in the case of science and religious education (RE), there is not the traditional relationship that may be seen in science and maths or across humanities subjects. More awareness of content taught in other departments is important for pupils' coherent experience of curriculum and schooling. This article reports on data from 10 focus groups with 50 participants from six universities, where student teachers of science and RE revealed a complex picture of relationships between the two departments in their placement schools. Furthermore, this article reports findings from a survey where 244 teachers and student teachers of science and RE shared their perspectives on the relationship between the two school departments. The measure was adapted from Barbour's typology, a classification describing the nature of the relationship between science and religion in a range of literature. The terms ‘conflict’, ‘independence’, ‘dialogue’, ‘collaboration’ and ‘integration’ were presented to teachers of both subjects. Little evidence was found of conflict between science and RE departments, but more ‘independence’ than ‘dialogue’ between the two departments was reported. In the light of these findings, the benefits of boundary crossing are explored alongside the role teachers should play in boundary crossing

    Multimodal classroom interaction analysis using video-based methods of the pedagogical tactic of (un)grouping

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    Grouping of people and/or things in school can involve challenging pedagogical problems and is a recurrent issue in research literature. Grouping of pupils sometimes aids learning, but detailed video-based analysis of how teachers (and pupils) group or ungroup (termed ‘(un)grouping’) in classrooms is rare. This multimodal classroom interaction analysis study builds on previous work by exploring how the Pedagogy Analysis Framework can help untangle complicated classroom interactions involving (un)grouping and identifies sixteen types of (un)grouping. The sample size is one class of thirty pupils (10-year-olds), their class teacher, and teaching assistant. Four research methods were used (lesson video analysis, teacher verbal protocols, pupil group verbal protocols, and individual teacher interviews). Six hours of data were video recorded (managed using NVivo). Data were analysed by two educational researchers, the class teacher, and two groups of pupils (three girls and three boys). The methodology is Straussian Grounded Theory. Data were recorded in 2019. We present how often participants (un)grouped during a lesson. We propose and use a grounded theory for (un)grouping which we call the ‘Exclusion, Segregation, Integration, and Inclusion (ESII) model’. Additionally, we discuss how misinformation and disinformation can complicate analysis of (un)grouping and examine different perspectives on (un)grouping

    Science and RE teachers' perspectives on the purpose of RE on the secondary school curriculum in England

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    Renewed interest in curriculum in English schooling over the past decade has emanated from a particular focus on the place and role of knowledge in the classroom. Significant changes in policy and examination specifications have led to changes in religious education (RE). However, little is known about teachers' perspectives on the purpose of RE. We asked teachers of science and RE what they understood as the purpose of RE on the school curriculum. Data from 10 focus groups and a survey with 276 secondary teachers demonstrated that many secondary teachers of science have a different understanding to RE teachers of the purpose of RE on the school curriculum. Findings also show a lack of consensus from RE teachers on the purpose of RE, suggesting the impact of the knowledge turn in RE is not as strong as the Ofsted Research Review implies. Findings are significant as little is known about how knowledge works across disciplinary boundaries in schools. If students are to come to a full understanding of how knowledge works, teachers need to have some understanding of how knowledge is being constructed and utilised in other curriculum subjects. Knowledge of the intended purpose of RE is important for respectful co-existence of subjects on the curriculum and essential when RE is declining as a subject in secondary schools

    Rotational Effects of Twisted Light on Atoms Beyond the Paraxial Approximation

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    The transition probability for the emission of a Bessel photon by an atomic system is calculated within first order perturbation theory. We derive a closed expression for the electromagnetic potentials beyond the paraxial approximation that permits a systematic multipole approximation . The matrix elements between center of mass and internal states are evaluated for some specially relevant cases. This permits to clarify the feasibility of observing the rotational effects of twisted light on atoms predicted by the calculations. It is shown that the probability that the internal state of an atom acquires orbital angular momentum from light is, in general, maximum for an atom located at the axis of a Bessel mode. For a Gaussian packet, the relevant parameter is the ratio of the spread of the atomic center of mass wave packet to the transversal wavelength of the photon.Comment: 10 pages, no figure

    Science religion encounters, epistemic trespass, neighbourliness and overlapping domains: theorisation and quantitative evidence of extent

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    This study advances a concept of science religion encounter (SRE), with preliminary theorisation and shares findings on the extent and nature of such encounters reported by secondary religious education and science teachers. SREs are interdisciplinary engagements in classrooms involving subject knowledge from more than one subject. The researchers hypothesised they may arise unexpectedly, when a pupil asks a question, or be teacher-planned and intended. This article further elaborates the concept of SRE with reference to the concepts of ‘epistemic trespassing’ (ET), epistemic neighbourliness, and overlapping domains, introducing these to the field of education. The study is contextualised in the school classroom with quantitative data gathered among beginning and experienced teachers measuring whether this ET in SRE topics enter the classroom via ‘spontaneity’ or via a ‘deliberateness’. This clarifies the different roles a teacher may play and offers considerations for teacher development when navigating an SRE in ways that potentially reduce lost learning

    Coding accuracy for Parkinson's disease hospital admissions:implications for healthcare planning in the UK

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    ObjectivesHospital Episode Statistics data are used for healthcare planning and hospital reimbursements. Reliability of these data is dependent on the accuracy of individual hospitals reporting Secondary Uses Service (SUS) which includes hospitalisation. The number and coding accuracy for Parkinson's disease hospital admissions at a tertiary centre in Birmingham was assessed.Study designRetrospective, routine-data–based study.MethodsA retrospective electronic database search for all Parkinson's disease patients admitted to the tertiary hospital over a 4-year period (2009–2013) was performed on the SUS database using International Classification of Disease codes, and on the local inpatient electronic prescription database, Prescription and Information Communications System, using medication prescriptions. Capture-recapture methods were used to estimate the number of patients and admissions missed by both databases.ResultsFrom the two databases, between July 2009 and June 2013, 1068 patients with Parkinson's disease accounted for 1999 admissions. During these admissions, the Parkinson's disease was coded as a primary or secondary diagnosis. Ninety-one percent of these admissions were recorded on the SUS database. Capture-recapture methods estimated that the number of Parkinson's disease patients admitted during this period was 1127 patients (95% confidence interval: 1107–1146). A supplementary search of both SUS and Prescription and Information Communications System was undertaken using the hospital numbers of these 1068 patients. This identified another 479 admissions. SUS database under-estimated Parkinson's disease admissions by 27% during the study period.ConclusionThe accuracy of disease coding is critical for healthcare policy planning and must be improved. If the under-reporting of Parkinson's disease admissions on the SUS database is repeated nationally, expenditure on Parkinson's disease admissions in England is under-estimated by approximately £61 million per year
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