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Hands on - hands off: on hitting your thumb with a virtual hammer
In a wired world even the most physically embodied craft skills are affected by computer facilitated communication. To consider how different sorts of space â both real and virtual â influence the learning of craft skills this paper presents three types of space â the ârealâ space of a jewellery workshop, an online âwikiâ space for learning how to make a folding knife mediated by face to face interaction and an online discussion group about French Horn making. Some features common to the learning of any craft skill are discussed as well as some current ideas about the influence of networked communication on the way people relate to each other. Conclusions are drawn about the relationships between different types of learner, different types of skill and different types of learning space which demonstrate that while there may be no substitute for face to face contact in learning the most embodied craft skills, even in real-world settings a significant proportion of learning depends on social interaction which may be reproduced online.
Keywords:
Craft learning; Apprenticeship; Communities of Practice; Online Networks</p
Photographic investigation of propellant stream behavior in a firing rocket engine, volume I Technical summary report, 1 Aug. 1964 - 28 Feb. 1966
Photographic study to obtain injection and combustion patterns of F-1 rocket engine injector element
Sketchy rendering for information visualization
We present and evaluate a framework for constructing sketchy style information visualizations that mimic data graphics drawn by hand. We provide an alternative renderer for the Processing graphics environment that redefines core drawing primitives including line, polygon and ellipse rendering. These primitives allow higher-level graphical features such as bar charts, line charts, treemaps and node-link diagrams to be drawn in a sketchy style with a specified degree of sketchiness. The framework is designed to be easily integrated into existing visualization implementations with minimal programming modification or design effort. We show examples of use for statistical graphics, conveying spatial imprecision and for enhancing aesthetic and narrative qualities of visual- ization. We evaluate user perception of sketchiness of areal features through a series of stimulus-response tests in order to assess usersâ ability to place sketchiness on a ratio scale, and to estimate area. Results suggest relative area judgment is compromised by sketchy rendering and that its influence is dependent on the shape being rendered. They show that degree of sketchiness may be judged on an ordinal scale but that its judgement varies strongly between individuals. We evaluate higher-level impacts of sketchiness through user testing of scenarios that encourage user engagement with data visualization and willingness to critique visualization de- sign. Results suggest that where a visualization is clearly sketchy, engagement may be increased and that attitudes to participating in visualization annotation are more positive. The results of our work have implications for effective information visualization design that go beyond the traditional role of sketching as a tool for prototyping or its use for an indication of general uncertainty
Sexual offenderâs experiences of polygraph testing: a thematic study in three probation trusts
Post-conviction polygraph testing of sexual offenders is controversial and the use of the polygraph as a means of supporting supervision of sexual offenders has only recently been explored. This study quantitatively examined qualitatively offender managersâ and sexual offendersâ views on the mandatory use of the polygraph in a community-based supervision.
Fifteen polygraphed offenders and their 10 offender managers (polygraph group), and 10 non-polygraphed offenders and their ten offender managers (comparison group) were asked about their experiences and perceptions of a mandatory polygraph use. Using thematic analysis, the results provided four main themes: (1) truth detection, (2) perceptions of behaviour change, (3) perceptions of polygraph as part of supervision, and (4) national implementation of polygraph testing.
Results suggest several benefits to mandatory polygraph testing as a support for supervision, including offenders making more high-risk disclosures, motivating offender honesty, and aiding offendersâ compliance with licence conditions
Understanding AGB evolution in Galactic bulge stars from high-resolution infrared spectroscopy
An analysis of high-resolution near-infrared spectra of a sample of 45
asymptotic giant branch (AGB) stars towards the Galactic bulge is presented.
The sample consists of two subsamples, a larger one in the inner and
intermediate bulge, and a smaller one in the outer bulge. The data are analysed
with the help of hydrostatic model atmospheres and spectral synthesis. We
derive the radial velocity of all stars, and the atmospheric chemical mix
([Fe/H], C/O, C/C, Al, Si, Ti, and Y) where possible. Our ability
to model the spectra is mainly limited by the (in)completeness of atomic and
molecular line lists, at least for temperatures down to K. We find that the subsample in the inner and intermediate
bulge is quite homogeneous, with a slightly sub-solar mean metallicity and only
few stars with super-solar metallicity, in agreement with previous studies of
non-variable M-type giants in the bulge. All sample stars are oxygen-rich,
C/O1.0. The C/O and carbon isotopic ratios suggest that third dredge-up
(3DUP) is absent among the sample stars, except for two stars in the outer
bulge that are known to contain technetium. These stars are also more
metal-poor than the stars in the intermediate or inner bulge. Current stellar
masses are determined from linear pulsation models. The masses, metallicities
and 3DUP behaviour are compared to AGB evolutionary models. We conclude that
these models are partly in conflict with our observations. Furthermore, we
conclude that the stars in the inner and intermediate bulge belong to a more
metal-rich population that follows bar-like kinematics, whereas the stars in
the outer bulge belong to the metal-poor, spheroidal bulge population.Comment: 21 pages, 13 figures, 6 tables (incl. appendix), years of work,
published in MNRA
Variation in the transfer of radionuclide to freshwater fish: phylogeny or feeding strategy?
For both terrestrial vascular plants and marine organisms if has been demonstrated the differences in radionuclide transfer between species can be related to their evolutionary history or phylogeny. Relationships between phylogeny and radionuclide transfer offer a potential approach to help to derive best estimate values if data for a given species-radionuclide are not available.
In this paper we describe the analyses of data for radionuclide transfer to freshwater fish from a data base recently compiled to support activities of both the IAEA and ICRP. There are sufficient data in the database to test the hypothesis that radionuclide transfer can be related to the evolutionary of freshwater fish for caesium, strontium and uranium. For instance, the database contains 750 entries for caesium considering nearly 70 species of fish. Initial results indicate that phylogeny does explain some of the variation in radionuclide transfer between species of fish. However, feeding strategy also explains variation in radionuclide transfer between species. In this paper we will compare our results to establish if phylogeny or feeding strategy is the most useful predictor of radionuclide transfer to freshwater fish
Fast calibrated additive quantile regression
We propose a novel framework for fitting additive quantile regression models,
which provides well calibrated inference about the conditional quantiles and
fast automatic estimation of the smoothing parameters, for model structures as
diverse as those usable with distributional GAMs, while maintaining equivalent
numerical efficiency and stability. The proposed methods are at once
statistically rigorous and computationally efficient, because they are based on
the general belief updating framework of Bissiri et al. (2016) to loss based
inference, but compute by adapting the stable fitting methods of Wood et al.
(2016). We show how the pinball loss is statistically suboptimal relative to a
novel smooth generalisation, which also gives access to fast estimation
methods. Further, we provide a novel calibration method for efficiently
selecting the 'learning rate' balancing the loss with the smoothing priors
during inference, thereby obtaining reliable quantile uncertainty estimates.
Our work was motivated by a probabilistic electricity load forecasting
application, used here to demonstrate the proposed approach. The methods
described here are implemented by the qgam R package, available on the
Comprehensive R Archive Network (CRAN)
Evolving social dynamics prime thermal tolerance during a poleward range shift
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