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'Man-up, go and get an ice-pack.' Gendered stereotypes and binaries within the classroom: a thing of the past?
Get PDFGendered expectations are deeply embedded within the fabric of a society and the classroom is no exception; binaries habitually pervade attitudes, practices and pedagogies. This small-scale qualitative-interpretive study, undertaken in one rural primary school in North Wales, explores how the learning of gender is constructed, enacted and challenged by participants functioning within Key Stage 2 (children aged 8-11 years); issues experienced by, both girls and boys, to cogitate implications for gender equity and for teachers’ work. The fieldwork revealed many school participants continue to draw upon essentialist binary discourse, predominantly based on biological theories, to explain differences between boys and girls relating to classroom behaviour, subject attainment, curricular preferences and career pathways. Constant reference was made to acceptable ways of ‘doing masculinity’ and the ‘high-achieving, conforming school girl culture’. Children recognised gender binaries used by teachers and were aware of societal advances in gender equity. Despite decades of research and policies, we are still some way to ameliorating gender binaries and stereotypes in this phase of schooling. Therefore, there is an urgent need for practitioners to become more reflexively aware about the complex ways in which gendered dualisms and hierarchies perpetuate and dictate relations and pedagogical practices, which constrain experiences and opportunities for girls and boys and, to incorporate multiple ways of thinking and doing gender in classrooms
The absolute calibration of high-precision optical flats across a wide range of spatial frequencies
Get PDFWe analyse the applicability of the two-flat-test calibration method across wide spatial frequency range based on its calculated accuracy. A number of simulations have been performed to determine the accuracy of the absolute calibration. The simulation results show that the two-flat-test calibration method is applicable to surfaces within the spatial frequency range from 1.67×10−1 to 1.67×10−3 mm−1
Solution characteristics and thermorheology of Prosopis africana seed polysaccharide
Get PDFOf about forty four species of the Prosopis family known, only Prosopis africana is indigenous to Africa. We have isolated the polysaccharide constituent of P.rosopisafricana seed and studied its solution properties. The polysaccharide had a weight-average molecular weight of 1.72 × 106 g/mol and intrinsic viscosity of 11.6 dL/g. The effect of concentration and temperature on the polysaccharide viscosity and microstructure were investigated under steady and dynamic shear. The polysaccharide showed typical shear thinning characteristics and the critical angular frequency at the G-crossover points (G′ = G″) was concentration and temperature dependent and shifted to lower frequencies at higher polysaccharide concentrations. The onset of polymer overlap occurred at a critical concentration, c* = 0.186 g/dL with slope of 1.4 below and 4.4 above the point of polymer overlap concentration. The rheological behavior was studied as a function of temperature and the activation energy for viscous flow of 2% solution of the polysaccharide was calculated to be 24.3 kJ/mol. The rheological properties were shown to be similar to guar gum and hence it has potential use as a thickener in foods
Inductive heating effects on friction surfacing of stainless steel onto an aluminium substrate
Get PDFAn experimental setup was designed to compare the principal process parametric relationships with the classical approach to friction surfacing with the addition of inductive heating. The production of the flash is described quantitatively and its influence on coating geometry and mass is presented. It was found that the coating mass and thickness decreased for an increase in the rotational speed of the consumable rod; the amount of flash produced by the consumable rod also increased. However, the e_ect of an increase in this rod contact pressure on the coating thickness is insignificant, whilst the coating mass decreases with rising pressure and the coating width increases coupled with an increase in flash production. Cross sections showed good bonding quality and mechanical interlocking at the bond interface. The substrate-coating interface showed a varying degree of mechanical interlocking and the presence of cavitations. Bond strength values applying shear and push-o_ testing of up to 106 MPa and 96 MPa, respectively, could be identified
Calculations of actuator promising designs
Get PDFBimetallic actuators are widely used in electro-technical, adjusting, safety and other systems. Actuator calculation is a problem of current interest. It is required to develop new actuator designs with better performance. Finite element method was used for complex shape bimetallic actuator calculation. The algorithm is implemented in Abaqus finite element software. Actuator elastic characteristic and deformed shape are the results of the calculation. Calculation results for different actuators were compared. New design of thermo-bimetallic actuator consisting of a shallow dome and an U-shaped tongue with was described. It deforms with a “snap-through” when the heat is applied. The layers of shallow dome and tongue are placed on opposite sides, making possible the maximization of actuator characteristic points displacement. The proposed actuator design and the developed calculation methodology can be recommended to the implementation to the calculation practice and actuator element base development
Carbon Meets Silicon
Get PDFThis exhibition was is in association with ITA(15), the 6th International Conference on Internet Technologies and Applications. The conference drew together researchers and developers from academia and industry across all fields of Internet computing, engineering and art and design.
The inspiration for the title of this exhibition came from the work of Alan Turing and his exploration of artificial intelligence versus cognitive psychology. The key questions surrounding whether thoughts and consciousness can be produced by a mechanical systems have fascinated computer scientists, mathematicians, cognitive psychologists and artists since the 1950’s. Many thought that the difference between these two fields was concerned with whether the mechanical system in question was carbon based brain or silicon based computer (Sternberg, R.J. and Kaufman, J, C. (2013). How do we begin to explore these questions? According to Michael Polanyi (1962) ‘aesthetic insight motivates the early stages of much scientific research’. This exhibition offers tacit knowledge embodied in the artwork that may or may not question the above, but certainly explore the concept of carbon and silicon as metaphors for the changing face of art practice over the last fifty years. Carbon references the materiality of the art object, the tradition of art materials such as paint, bronze etc. and silicon references how this materiality is questioned in the light of new media utilizing the digital or the virtual bringing artists closer to scientists and engineers. When carbon meets silicon it creates silicon carbide, a compound that exists as artificial diamonds and star dust, a transformative process that is akin to the alchemy of making art.
References
Sternberg, RJ, and Kaufman, J, C. (2013) The Evolution of Intelligences, Psychology Press.
Polanyi, M. (1962) Personal Knowledge: towards a post critical philosophy. London Routledge
The exhibition has been curated by Dr Susan Ligget
The psychological type profile of Christians participating in fellowship groups or in small study groups: Insights from the Australian National Church Life Survey
Get PDFThe Australian National Church Life Survey draws on psychological type theory to facilitate insights into the connection between individual psychological profiles and preferences for different religious expressions. Drawing on data provided by 2355 participants in the 2006 congregation survey, this analysis profiles those members of church congregations who are drawn to participation in small prayer, discussion or Bible study groups, or to participation in fellowship and social groups. The key findings are that extraverts and feeling types are over-represented in the fellowship and social groups and that intuitive types are over-represented in small prayer, discussion or Bible study groups
Broken bar fault diagnosis for induction machines under load variation condition using discrete Wavelet transform
Get PDFThe paper presents a new approach for detection of broken rotor bar fault in squirrel cage induction motors operating under varying load conditions. A mathematical model used in the presented method was developed using winding function approach to provide indication references for induction motor parameters under load variation. The model shows a strong relationship between broken rotor bar fault and stator current. The method is based on analysis of stator current using discrete wavelet transform. To verify the proposed method a squirrel cage induction motor with 1, 2 and 3 broken bars at no-load, half- and full-load conditions was investigated. Obtained experimental results confirmed the validity of the proposed approach
Improvement to thin film CdTe solar cells with controlled back surface oxidation
Get PDFThin film CdTe solar cells were produced by MOCVD, at atmospheric pressure, under a hydrogen atmosphere (i.e. oxygen-free). Window layer alloying with zinc (forming Cd1−xZnxS) and extrinsic p-type doping with arsenic (giving CdTe:As) have been used to improve photovoltaic solar cell performances, but as-grown MOCVD-CdTe PV cells are still typically characterised by low Voc (~620–690 mV). Post-deposition annealing in air for 30 min at low temperature (170 °C) prior to evaporation of the back contacts led to significant increases in Voc and FF. XPS measurements revealed back surface oxidation, resulting in formation of Te–O species. This was also the case for a device aged under ambient laboratory conditions. Extended annealing in air of a fresh device, for up to 180 min, continued to improve both Voc and FF. At longer annealing times the Voc remained relatively stable whilst the FF started to deteriorate. External quantum efficiency showed loss of photocurrent generation after excessive oxidation prior to back contact metallisation. Controlled back surface oxidation resulted in Voc values exceeding 800 mV and a best cell efficiency of 15.3
Using the parallel stacked mirror model to analytically describe diffraction in the planar volume reflection grating with finite absorption
Get PDFThe PSM model of grating diffraction is extended to include a complex refractive index for the case of an unslanted reflection geometry at oblique incidence and for the σ-polarization. The well-known theoretical upper diffraction efficiency limit applicable to reflective absorption gratings described by Kogelnik’s coupled-wave theory, is shown to be directly derivable from the PSM model. Analytical formulae for the diffraction efficiency of phase, absorption and mixed harmonic-index gratings are compared with numerical computations using a rigorous coupled wave description. A conventional truncated coupled-wave description, similar to Kogelnik’s approach, is also derived from the harmonic-index rigorous coupled wave equations by limiting the propagating modes to a signal and reference wave and by ignoring second order derivatives. At low to moderate average loss the PSM theory is observed to provide a somewhat better fit to the rigorous coupled wave calculations, and this is particularly evident for gratings which are dominated by phase modulation. As the average absorption coefficient is increased, all three models show the diffractive response sharpening around Bragg resonance and the characteristic sideband structure attenuating and then disappearing altogether, giving rise to a broader spectral behavior away from resonance. At high average loss, the truncated coupled wave model is observed to very marginally out-perform PSM. However, overall the PSM model is found to provide an exceedingly good description of the general mixed phase-absorption unslanted reflection grating with finite average loss