1,971 research outputs found

    What does engagement look like in a Media Studies classroom?

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    In wider discourses about teaching and learning, “engagement” has become something of a contested term, with teachers and educationalists often arguing about what being engaged in education actually involves. This contestation is compounded in media education, because the teacher has to deal with multiple conceptions of audience and, as a consequence, multiple meanings of the term engagement. In this essay, these conceptions and meanings are explored using some primary data taken from surveys of students and teachers from A-Level Media Studies classes, who were asked about both their engagement with the texts they taught and studied on the course, and their engagement with the wider critical study of media texts. The analysis of the data shows varying types and levels of engagement, some of which are personal, some educational and some academically critical. The authors seek to categorise these “engagement events” in different ways and highlight the idea that engagement in the study of media texts is very different to other types of audience engagement

    Monotone graph limits and quasimonotone graphs

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    The recent theory of graph limits gives a powerful framework for understanding the properties of suitable (convergent) sequences (Gn)(G_n) of graphs in terms of a limiting object which may be represented by a symmetric function WW on [0,1][0,1], i.e., a kernel or graphon. In this context it is natural to wish to relate specific properties of the sequence to specific properties of the kernel. Here we show that the kernel is monotone (i.e., increasing in both variables) if and only if the sequence satisfies a `quasi-monotonicity' property defined by a certain functional tending to zero. As a tool we prove an inequality relating the cut and L1L^1 norms of kernels of the form W1−W2W_1-W_2 with W1W_1 and W2W_2 monotone that may be of interest in its own right; no such inequality holds for general kernels.Comment: 38 page

    The effect of alkalisation on the mechanical properties of natural fibres

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    A study on the effect of alkalisaton using 3% NaOH solution was carried out on Flax, Kenaf, Abaca and Sisal to observe the impact that the common pre-treatment process has on fibre mechanical properties. The result of the investigation indicated that over-treatment of natural fibres using NaOH could have a negative effect on the base fibre properties. It is concluded that a treatment time of less than 10 minutes is sufficient to remove hemicelluloses and to give the optimum effect

    Mechanical testing of natural fibre reinforced polyester resin composites and Mode 1 fracture toughness testing of resin blocks

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    Recent European Parliament directive requires companies to achieve materials recycling greater than 80% in particular in the automotive sector [1]. The research on natural fibre based composite materials fits well into this ecological image. The advantages of natural fibres over synthetic materials include, low density, relative cheapness, availability and biodegradability. In this paper we explore the fabrication and mechanical testing of natural fibre composites and this is part of an on going study at Strathclyde University and describes the fabrication of composites using natural fibre and styrene polyester resin. The properties of the synthetic resin can be varied by changing the catalysts concentration and flexural (three point bending) and single-edged notched bending (SENB) properties are reported at different concentrations of the catalyst

    Vacuum infusion of natural fibre composites for structural applications

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    Numerous methods of manufacturing natural fibre composites have been reported in the literature, including compression moudling, often in conjunction with a hot press. Other forms of composite manufacture include 'Vacuum Assisted Resin Transfer Moulding' (VATRM) and the 'Seemann Composite Resin Infusion Moulding Process' (SCRIMP). These methods have been reported to produce natural fibre composies with reasonable mechanical properties [1-2]. In this paper, a vacuum infusion rig is described that has been developed to produce consistent quality composite plates for studies into optimising natural fibre composites. The process aims to harness the benefits of vacuum infusion and compression moulding, where vacuum infusion encourages the removal of trapped air in the system and hence avoid reduction, and additional compression moulding can help to achieve high volume fractions that are otherwise difficult in other processes

    Embedding Four-directional Paths on Convex Point Sets

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    A directed path whose edges are assigned labels "up", "down", "right", or "left" is called \emph{four-directional}, and \emph{three-directional} if at most three out of the four labels are used. A \emph{direction-consistent embedding} of an \mbox{nn-vertex} four-directional path PP on a set SS of nn points in the plane is a straight-line drawing of PP where each vertex of PP is mapped to a distinct point of SS and every edge points to the direction specified by its label. We study planar direction-consistent embeddings of three- and four-directional paths and provide a complete picture of the problem for convex point sets.Comment: 11 pages, full conference version including all proof

    A simple chemical approach to regenerating strength of thermally damaged glass fibre for reuse in composites

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    A key technical barrier to the reuse of thermally recycled glass fibres in composite applications is their low mechanical strength. This research study looks into the effect of alkaline treatments in regenerating the strength of glass fibres which were heated in a furnace to simulate thermal recycling conditions. Up to 100% strength increase of the fibres can be achieved through a simple treatment in alkaline solution. It was found that the nature of alkali, concentration, and treatment duration had a significant effect on the extent of strength recovery of the fibres. These treatments could potentially be implemented to thermally recycled glass fibres on an industrial scale, to allow their reprocessing into second-life composite materials. As well as optimising the reaction conditions to regenerate fibre strength, an examination of the surface morphology was carried out using various techniques. In addition, the kinetics of dissolution of glass fibres in alkaline solutions was investigated in order to further understand the strength regeneration mechanism

    Relative Riemann-Zariski spaces

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    In this paper we study relative Riemann-Zariski spaces attached to a morphism of schemes and generalizing the classical Riemann-Zariski space of a field. We prove that similarly to the classical RZ spaces, the relative ones can be described either as projective limits of schemes in the category of locally ringed spaces or as certain spaces of valuations. We apply these spaces to prove the following two new results: a strong version of stable modification theorem for relative curves; a decomposition theorem which asserts that any separated morphism between quasi-compact and quasi-separated schemes factors as a composition of an affine morphism and a proper morphism. (In particular, we obtain a new proof of Nagata's compactification theorem.)Comment: 30 pages, the final version, to appear in Israel J. of Mat
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