709 research outputs found

    WATCH Water and Global Change. Newsletter no. 1

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    WATCH is an integrated project funded by the EU and is co-ordinated by CEH Wallingford. This project aims to unite researchers to evaluate the global water cycle's response to current and future drivers of climate change. In this first newsletter we describe the project objectives, the progress made in the first year and detail the outcomes of the model intercomparison workshop

    Shear-enhanced dispersion of a wound substance as a candidate mechanism for variation potential transmission

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    A variation potential (VP) is an electrical signal unique to plants that occurs in response to wounding or flaming. The propagation mechanism itself, however, is known not to be electrical. Here we examine the hypothesis that VP transmission occurs via the transport of a chemical agent in the xylem. We assume the electrical signal is generated locally by the activation of an ion channel at the plasma membrane of cells adjacent to the xylem. We work on the assumption that the ion channels are triggered when the chemical concentration exceeds a threshold value. We use numerical computations to demonstrate the combined effect of advection and diffusion on chemical transport in a tube flow, and propose shear-enhance

    A frame signature matrix for analysing and comparing interaction design behaviour

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    Protocol studies are an established method to investigate design behaviour. In the context of a project to investigate novice interaction design (ID) behaviour across protocols and cultures, we found that existing design behaviour analysis frameworks did not provide reliable results. This paper describes the development of a new approach to analyse and compare ID behaviour using verbal protocols. We augment Schön’s basic design and reflection cycle with construction of a frame signature matrix and analogical categorisation coding. We demonstrate this approach by comparing two protocols of novice interaction designers in Botswana. The initial findings indicate that this approach increases consistency and accuracy of coding, and that there are different degrees of reframing for the design problem and solutions

    A protocol study of novice interaction design behaviour in Botswana: solution-driven interaction design

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    Think aloud studies and protocol analysis are well-known in the field of HCI, but most often these studies focus on usability evaluations, or on the use of technology. Rarely are they used to investigate the behaviour of interaction designers. In this paper, we report on a protocol study with novice interaction designers in Botswana. Participants had just completed the design section of an undergraduate module on Interaction Design that actively promotes a problem-driven approach to the design of interactive products, yet the participants behaved in a way that is closer to a solution-driven approach. The module emphasizes user-centred design, prototyping methods to support design development, and evaluating design detail. Yet participants suggest solutions before exploring the context of use, use prototyping methods to capture, rather than to develop, designs, and do not produce detailed designs. In a problem-solving context, some of these behaviours are typical of novices, but in a design context they are also seen in experienced designers. The results presented here reveal the detail of the approach adopted by these students, and contribute to the wider debate concerning the internationalization of HCI education

    How water flow, geometry and material properties drive plant movements

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    Plants are dynamic. They adjust their shape for feeding, defence and reproduction. Such plant movements are critical for their survival. We present selected examples covering a range of movements from single cell to tissue level and over a range of timescales. We focus on reversible turgor-driven shape changes. Recent insights into the mechanisms of stomata, bladderwort, the waterwheel and the Venus flytrap are presented. The underlying physical principles (turgor, osmosis, membrane permeability, wall stress, snap buckling, elastic instability) are highlighted and advances in our understanding of these processes are summarised

    Strategic Planning Effective Cooperation for Spatial Planning Across Boundaries

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    City regions require spatial planning over their whole territory in order to achieve better development outcomes for people. However, city regions are usually characterised by fragmented local governance, and there is a need to overcome this through cooperation. This paper highlights some elements of good practice to achieve this improvement, including the use of digital technology

    Using earth observation data to evaluate a land surface model in three Siberian catchments

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    In this paper, we analyse the ability of the JULES (Joint UK Land Environment Simulator) model to simulate the physical conditions in the terrestrial Arctic using satellite-based earth observation data products. Catchment-average seasonal surface temperatures and snow cover are constructed over the largest river basins of the Eurasian Arctic (the Ob, Lena and Yenisei) and compared with the modelled values. The results indicate that the modelled snow cover decreases too quickly in spring in all studied areas, and that the modelled surface temperature of snow-free areas is too high. There are several causes of uncertainty in both the model outputs and the earth observation products, and care has to be taken to ensure consistent use and sampling of the data. The results indicate that earth observation products provide important information that can assist in the diagnosis of problems in a land-surface model
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