7,342 research outputs found
Kolmogorov Similarity Hypotheses for Scalar Fields: Sampling Intermittent Turbulent Mixing in the Ocean and Galaxy
Kolmogorov's three universal similarity hypotheses are extrapolated to
describe scalar fields like temperature mixed by turbulence. By the analogous
Kolmogorov third hypothesis for scalars, temperature dissipation rates chi
averaged over lengths r > L_K should be lognormally distributed with
intermittency factors I that increase with increasing turbulence energy length
scales L_O as I_chi-r = m_T ln(L_O/r). Tests of Kolmogorovian velocity and
scalar universal similarity hypotheses for very large ranges of turbulence
length and time scales are provided by data from the ocean and the Galactic
interstellar medium. The universal constant for turbulent mixing intermittency
m_T is estimated from oceanic data to be 0.44+-0.01, which is remarkably close
to estimates for Kolmogorov's turbulence intermittency constant m_u of
0.45+-0.05 from Galactic as well as atmospheric data. Extreme intermittency
complicates the oceanic sampling problem, and may lead to quantitative and
qualitative undersampling errors in estimates of mean oceanic dissipation rates
and fluxes. Intermittency of turbulence and mixing in the interstellar medium
may be a factor in the formation of stars.Comment: 23 pages original of Proc. Roy. Soc. article, 8 figures; in
"Turbulence and Stochastic Processes: Kolmogorov's ideas 50 years on", London
The Royal Society, 1991, J.C.R. Hunt, O.M. Phillips, D. Williams Eds., pages
1-240, vol. 434 (no. 1890) Proc. Roy. Soc. Lond. A, PDF fil
Adaptation Knowledge from the Case Base
Case adaptation continues to be one of the more difficult aspects of case-based reasoning to automate. This paper looks at several techniques for utilising the implicit knowledge contained in a case base for case adaptation in case-based reasoning systems. The most significant of the techniques proposed are a moderately successful data mining technique and a highly successful artificial neural network technique. Their effectiveness was evaluated on a footwear design problem
An Ecological Dynamics perspective on Adventure Tourism
Traditional definitions for adventure tourism have focused on the adventure tourism activity or the adventure tourism environment. In these cases the activity is most often associated with risk and the environment associated with unfamiliarity and natural terrains. Critiques of these definitions have pointed out that this traditional perspective is limited. The risk focus is paradoxical as clients purchase adventure experiences involving risk and uncertainty, whereas tour operators must minimize the risk and emphasize safety. Additionally, adventure tourism can also take place in urban or man-made environments. Furthermore, the traditional definitions mostly ignore the lived experience of the adventure consumer. Individuals undertake adventure for a variety of reasons, including risk and thrills, health and well-being, connection to others and nature, recreational mastery, and personal development. We propose a nuanced conceptual understanding of adventure tourism within an ecological dynamics perspective that considers the relationship between the person, the adventure activity and the surrounding environment, and the recognition of affordances that support well-being. This theoretical approach provides a useful framework for operators and researchers that encourages a more personalized and meaningful experience for the tourist
The effect of Holstein-Friesian genotype and feeding system on selected performance parameters of dairy cows on grass-based systems of milk production in Ireland
End of project reportThe overall objective of this project was to assess, the effect of strain of Holstein-Friesian dairy cow, pasture-based feed system (FS) and their interaction on animal performance in terms of milk productivity and lactation profile, body weight (BW), body condition score (BCS), feed intake and energy balance (EB), reproductive performance and overall economic profitability
Validation of mid-infrared spectrometry in milk for predicting body energy status in Holstein-Friesian cows
Outdoor learning spaces: the case of forest school
© 2017 The Author. Area published by John Wiley & Sons Ltd on behalf of Royal Geographical Society (with the Institute of British Geographers). This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.This paper contributes to the growing body of research concerning use of outdoor spaces by educators, and the increased use of informal and outdoor learning spaces when teaching primary school children. The research takes the example of forest school, a form of regular and repeated outdoor learning increasingly common in primary schools. This research focuses on how the learning space at forest school shapes the experience of children and forest school leaders as they engage in learning outside the classroom. The learning space is considered as a physical space, and also in a more metaphorical way as a space where different behaviours are permitted, and a space set apart from the national curriculum. Through semi-structured interviews with members of the community of practice of forest school leaders, the paper seeks to determine the significance of being outdoors on the forest school experience. How does this learning space differ from the classroom environment? What aspects of the forest school learning space support pupils’ experiences? How does the outdoor learning space affect teaching, and the dynamics of learning while at forest school? The research shows that the outdoor space provides new opportunities for children and teachers to interact and learn, and revealed how forest school leaders and children co-create a learning environment in which the boundaries between classroom and outdoor learning, teacher and pupil, are renegotiated to stimulate teaching and learning. Forest school practitioners see forest school as a separate learning space that is removed from the physical constraints of the classroom and pedagogical constraints of the national curriculum to provide a more flexible and responsive learning environment.Peer reviewe
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