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A research-informed dialogic-teaching approach to early secondary school mathematics and science: the pedagogical design and field trial of the epiSTEMe intervention
The project undertook pedagogical research aimed at improving pupil engagement and learning in early secondary school physical science and mathematics. Using principles identified as effective in the research literature and drawing on a range of existing pedagogical resources, the project designed and trialled a classroom intervention, with associated professional development, in a form intended to be suited to implementation at scale. The most distinctive feature of the pedagogical approach is its inclusion of a component of dialogic teaching. Aimed at the first year of secondary education in English schools (covering ages 11â12), the intervention consists of a short introductory module designed to prepare classes for this dialogic teaching component, and topic modules which employ the pedagogical approach to cover two curricular topics in each of science and mathematics. A field trial was conducted over the 2010/2011 school year in 25 volunteer schools, randomly assigned to intervention and control groups. Within the intervention group, observation of lessons indicated that the level of dialogic teaching was higher for one of the topic modules than others. Evaluation focused on the effectiveness of the topic modules, each trialled in more than 10 classes containing a total of over 300 pupils, and compared with a group of similar composition. Overall, at this first implementation, learning gains under the intervention were no greater, although for individual topic modules the effects ranged from small negative to small positive. No difference was found between intervention and control groups either in the opinion of pupils about their classroom experience or in changes in their attitude towards subjects.Thanks are due to the Economic and Social Research Council which provided funding for the epiSTEMe project (RES-179-25-0003), to the teachers who generously volunteered to review, pilot and trial versions of the modules, to Christine Howe for her contribution to design and analysis, and to Andy Tolmie and Anna Vignoles for statistical advice.This is the final version of the article. It first appeared from Taylor & Francis via https://doi.org/10.1080/02671522.2015.112964
College Studentsâ Conceptions of Chemical Stability: The widespread adoption of a heuristic rule out of context and beyond its range of application
Development of Vibration During the Electromagnetic Ring Expansion Test
Magnetic pulse forming (MPF) techniques work on the principle of Lorentz force induced
by eddy current which can cause plastic deformation in a metal workpiece. Lorentz force
depends on parameters such as frequency and amplitude of input current, electromagnetic
properties of materials and distance between the work piece and coil. The development of
vibration as a consequence of elastic strain recovery in a ring expansion process using a
MPF technique has been identified and presented in this paper. Coupled mechanicalelectromagnetic
3D simulations were carried out to investigate the effect of various
magnetic pulse currents in the development of reversal of motion during the MPF process
using LS-DYNA package. Ring expansion using a multi-turn helix coil with an applied
pulse current, with the rings made of aluminum alloy AA6061 âT6 is investigated for the
effect of vibration during the process. The numerical results show good agreement with
the experimental work for various currents. The underlying principle of vibration and
formability has respectively been studied using force analysis and stress analysis. The
results also show that the 5.6kJ energy already increased the formability by ~66 percent in
comparison with the quasi-static formability value from the literature
The Effects of Fiscal Policy on Human Capital Accumulation: Evidence from OECD Countries
By using dynamic panel data estimation techniques for twenty-one OECD countries, this paper investigates the effects of government expenditures and four different types of tax policy innovations on the human capital accumulation process. Our results show that only income taxes have a significant negative effect on investment in human capital, measured by the tertiary enrolment rate
Coupling Experiment and Simulation in Electromagnetic Forming Using Photon Doppler Velocimetry
Modeling electromagnetic forming processes is in many ways simpler than modeling traditional metal forming processes. In electromagnetic forming the problem is often dominated by inertial acceleration by a magnetic field. This is a much better posed problem than the more traditional ones that are often dominated by complex three dimensional constitutive behavior and frictional effects. However, important aspects of the problem are dominated by the constitutive properties of the material, and often electromagnetic forming is performed in a regime where there is little reliable material strength data. Strain rates are often high (102 to 104 s-1 is the typical range for electromagnetic forming). Also, heat is generated both by ohmic heating as well as by plastic deformation, and peak temperatures can be quite high. Also, while hightemperature, high-strain-rate data is scarce, there is little or no data in cases where temperature rises significantly over very short times (tens of micro-seconds) as happens in electromagnetic metal forming. This rapid temperature rise is very important to the material response because the short time scales largely preclude the material from recovery and recrystallization processes and precipitates cannot dissolve as they normally would in an age-hardening alloy in these time scales. This presentation will show how advanced instrumentation, particularly the Photon Doppler Velocimeter (PDV) can be coupled with electromagnetic forming and provide both avenues to characterize material as well as to provide very critical tests of numerical models of the process
Comparing Mean & Peak Barbell Velocity During Traditional and Accentuated Eccentric Loaded Back Squats
MV: There were statistically significant main effects present for both condition (p = 0.002; g = 0.10-0.23) and load (p \u3c 0.001; g = 0.95-3.93). However, the condition x time interaction effect was not statistically significant (p = 0.259). ⢠PV: There were statistically significant main effects present for both condition (p = 0.016; g = 0.11-0.23) and load (p \u3c 0.001; g = 0.42-1.6), but there was no statistically significant condition x time interaction effect (p = 0.101). ⢠Post hoc analysis indicated that there was a significant difference between MV (p = 0.006) and PV (p = 0.032) between the traditional and 100% AEL conditions. ⢠Moderate effect sizes were found with MV between the traditional and 100% AEL conditions at both 70% CON (g = 0.55) and 80% CON (g = 0.70). ⢠No practically significant differences were found for PV
English secondary studentsâ thinking about the status of scientific theories: consistent, comprehensive, coherent and extensively evidenced explanations of aspects of the natural world â or just âan idea someone hasâ
Teaching about the nature of science (NOS) is seen as a priority for science education in many national contexts. The present paper focuses on one central issue in learning about NOS: understanding the nature and status of scientific theories. A key challenge in teaching about NOS is to persuade students that scientific knowledge is generally robust and reliable, yet also in principle always open to challenge and modification. Theories play a central role, as they are a form of conjectural knowledge that over time may be abandoned, replaced, modified, yet sometimes become well established as current best scientific understanding. The present paper reports on findings from interviews with 13â14 year olds in England where target knowledge presents theories as âconsistent, comprehensive, coherent and extensively evidenced explanations of aspects of the natural worldâ. Student thinking reflected a two-tier typology of scientific knowledge in which largely unsupported imaginative ideas (âtheoriesâ) became transformed into fairly definitive knowledge (such as laws) through relatively straightforward testing. These results are considered in relation to research into intellectual development which indicates that effective teaching in this area requires careful scaffolding of student learning, but has potential to contribute to supporting intellectual development across the curriculum.This is the author accepted manuscript. The final version is available from Taylor & Francis via http://dx.doi.org/10.1080/09585176.2015.104392
Secondary Studentsâ Thinking about Familiar Phenomena: Learnersâ explanations from a curriculum context where âparticlesâ is a key idea for organising teaching and learning
A Cognitive Model of an Epistemic Community: Mapping the Dynamics of Shallow Lake Ecosystems
We used fuzzy cognitive mapping (FCM) to develop a generic shallow lake
ecosystem model by augmenting the individual cognitive maps drawn by 8
scientists working in the area of shallow lake ecology. We calculated graph
theoretical indices of the individual cognitive maps and the collective
cognitive map produced by augmentation. The graph theoretical indices revealed
internal cycles showing non-linear dynamics in the shallow lake ecosystem. The
ecological processes were organized democratically without a top-down
hierarchical structure. The steady state condition of the generic model was a
characteristic turbid shallow lake ecosystem since there were no dynamic
environmental changes that could cause shifts between a turbid and a clearwater
state, and the generic model indicated that only a dynamic disturbance regime
could maintain the clearwater state. The model developed herein captured the
empirical behavior of shallow lakes, and contained the basic model of the
Alternative Stable States Theory. In addition, our model expanded the basic
model by quantifying the relative effects of connections and by extending it.
In our expanded model we ran 4 simulations: harvesting submerged plants,
nutrient reduction, fish removal without nutrient reduction, and
biomanipulation. Only biomanipulation, which included fish removal and nutrient
reduction, had the potential to shift the turbid state into clearwater state.
The structure and relationships in the generic model as well as the outcomes of
the management simulations were supported by actual field studies in shallow
lake ecosystems. Thus, fuzzy cognitive mapping methodology enabled us to
understand the complex structure of shallow lake ecosystems as a whole and
obtain a valid generic model based on tacit knowledge of experts in the field.Comment: 24 pages, 5 Figure
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