896 research outputs found

    Assimilation of radar altimeter data in numerical wave models: an impact study in two different wave climate regions

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    An operational assimilation system incorporating significant wave height observations in high resolution numerical wave models is studied and evaluated. In particular, altimeter satellite data provided by the European Space Agency (ESA-ENVISAT) are assimilated in the wave model WAM which operates in two different wave climate areas: the Mediterranean Sea and the Indian Ocean. The first is a wind-sea dominated area while in the second, swell is the principal part of the sea state, a fact that seriously affects the performance of the assimilation scheme. A detailed study of the different impact is presented and the resulting forecasts are evaluated against available buoy and satellite observations. The corresponding results show a considerable improvement in wave forecasting for the Indian Ocean while in the Mediterranean Sea the assimilation impact is restricted to isolated areas

    Ocean wave tracing v.1: a numerical solver of the wave ray equations for ocean waves on variable currents at arbitrary depths

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    Lateral changes in the group velocity of waves propagating in oceanic or coastal waters cause a deflection in their propagation path. Such refractive effects can be computed given knowledge of the ambient current field and/or the bathymetry. We present an open-source module for solving the wave ray equations by means of numerical integration in Python v3. The solver is implemented for waves on variable currents and arbitrary depths following the Wentzel–Kramers–Brillouin (WKB) approximation. The ray tracing module is implemented in a class structure, and the output is verified against analytical solutions and tested for numerical convergence. The solver is accompanied by a set of ancillary functions such as retrieval of ambient conditions using OPeNDAP, transformation of geographical coordinates, and structuring of data using community standards. A number of use examples are also provided.</p

    Using assignment data to analyse a blended information literacy intervention: a quantitative approach

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    This research sought to determine whether a blended information literacy learning and teaching intervention could statistically significantly enhance undergraduates’ information discernment compared to standard face-to-face delivery. A mixture of face-to-face and online activities, including online social media learning, was used. Three interventions were designed to develop the information literacies of first-year undergraduates studying Sport and Exercise at Staffordshire University and focused on one aspect of information literacy: the ability to evaluate source material effectively. An analysis was devised where written evaluations of found information for an assessment were converted into numerical scores and then measured statistically. This helped to evaluate the efficacy of the interventions and provided data for further analysis. An insight into how the information literacy pedagogical intervention and the cognitive processes involved in enabling participants to interact critically with information is provided. The intervention which incorporated social media learning proved to be the most successful learning and teaching approach. The data indicated that undergraduate students’ information literacy can be developed. However, additional long-term data is required to establish whether this intervention would have a lasting impact

    Considering the role of cognitive control in expert performance

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    © 2014, Springer Science+Business Media Dordrecht. Dreyfus and Dreyfus’ (1986) influential phenomenological analysis of skill acquisition proposes that expert performance is guided by non-cognitive responses which are fast, effortless and apparently intuitive in nature. Although this model has been criticised (e.g., by Breivik Journal of Philosophy of Sport, 34, 116–134 2007, Journal of the Philosophy of Sport, 40, 85–106 2013; Eriksen 2010; Montero Inquiry:An interdisciplinary Journal of Philosophy, 53, 105–122 2010; Montero and Evans 2011) for over-emphasising the role that intuition plays in facilitating skilled performance, it does recognise that on occasions (e.g., when performance goes awry for some reason) a form of ‘detached deliberative rationality’ may be used by experts to improve their performance. However, Dreyfus and Dreyfus (1986) see no role for calculative problem solving or deliberation (i.e., drawing on rules or mental representations) when performance is going well. In the current paper, we draw on empirical evidence, insights from athletes, and phenomenological description to argue that ‘continuous improvement’ (i.e., the phenomenon whereby certain skilled performers appear to be capable of increasing their proficiency even though they are already experts; Toner and Moran 2014) among experts is mediated by cognitive (or executive) control in three distinct sporting situations (i.e., in training, during pre-performance routines, and while engaged in on-line skill execution). We conclude by arguing that Sutton et al. Journal of the British Society for Phenomenology, 42, 78–103 (2011) ‘applying intelligence to the reflexes’ (AIR) approach may help to elucidate the process by which expert performers achieve continuous improvement through analytical/mindful behaviour during training and competition

    Action theory and the value of sport

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    I present a corrective to the formalist and conventionalist down-playing of physical actions in the understanding of the value of sport. I give a necessarily brief account of the Causal Theory of Action (CTA) and its implications for the normativity of actions. I show that the CTA has limitations, particularly in the case of failed or incomplete actions, and I show that failed or incomplete actions are constitutive of sport. This allows me to open up the space for another model, drawn from Aristotle, for failed or incomplete actions, conceived of as ‘doables’. This avoids some of the problems of the CTA. I explain the importance of difficult but doable actions, at which athletes often fail, and suggest that this establishes pro tanto value. Finally, I claim that this account of the actions that are constitutive of sport deepens our understanding of the value of sport as a whole

    Collaborative dynamic decision making: a case study from B2B supplier selection

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    The problem of supplier selection can be easily modeled as a multiple-criteria decision making (MCDM) problem: businesses express their preferences with respect to suppliers, which can then be ranked and selected. This approach has two major pitfalls: first, it does not consider a dynamic scenario, in which suppliers and their ratings are constantly changing; second, it only addressed the problem from the point of view of a single business, and cannot be easily applied when considering more than one business. To overcome these problems, we introduce a method for supplier selection that builds upon the dynamic MCDM framework of Campanella and Ribeiro [1] and, by means of a linear programming model, can be used in the case of multiple collaborating businesses plan- ning their next batch of orders together.Fundação para a CiĂȘncia e a Tecnologia, Portugal, under contract CONT DOUT/49/UNINOVA/0/5902/1/200

    Effects of decontaminated fish oil or a fish and vegetable oil blend on persistent organic pollutant and fatty acid compositions in diet and flesh of Atlantic salmon (Salmo salar)

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    The health benefits of seafood are well documented and based on the unique supply of n-3 highly unsaturated fatty acids (HUFA). Aquaculture now contributes ~50% of food-grade seafood globally and Atlantic salmon is a rich source of n-3 HUFA. However, salmon and other oily fish can accumulate lipophilic persistent organic pollutants (POPs), including dioxins (PCDD/Fs), polychlorinated biphenyls (PCBs) and polybrominated diphenyl ethers (PBDEs), derived largely from feed. In this study, triplicate groups of salmon, of initial weight 0.78 kg were fed one of three experimental diets for 11 weeks. The diets were coated with either a northern fish oil (FO) with a high POPs content (cNFO), the same oil that had been decontaminated (deNFO) or a blend of southern fish oil, rapeseed and soybean oils (SFO/RO/SO). Dietary PCDD/F + dioxin-like PCB (DL-PCB) concentrations were 17.36, 0.45 and 0.53 ng TEQ/kg, respectively. After 11 weeks, the flesh concentrations in fish fed the cNFO, deNFO and SFO/RO/SO diets were 6.42, 0.34 and 0.41 ng TEQ/kg, respectively. There were no differences in flesh eicosapentaenoic (EPA) and docosahexaenoic acids (DHA) between fish fed the cNFO or deNFO diets although EPA and DHA were reduced by 50 and 30%, respectively, in fish fed the SFO/RO/SO diet. Thus, decontaminated FO can be used to produce salmon high in n-3 HUFA and low in POPs. Salmon produced using deNFO would be of high nutritional value and very low in POPs and would utilise valuable fish oils that would otherwise be destroyed due to their high pollutant concentrations
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