200,812 research outputs found
Measuring and comparing the reliability of the structured walkthrough evaluation method with novices and experts
Effective evaluation of websites for accessibility remains problematic. Automated evaluation tools still require a significant manual element. There is also a significant expertise and evaluator effect. The Structured Walkthrough method is the translation of a manual, expert accessibility evaluation process adapted for use by novices. The method is embedded in the Accessibility Evaluation Assistant (AEA), a web accessibility knowledge management tool. Previous trials examined the pedagogical potential of the tool when incorporated into an undergraduate computing curriculum. The results of the evaluations carried out by novices yielded promising, consistent levels of validity and reliability. This paper presents the results of an empirical study that compares the reliability of accessibility evaluations produced by two groups (novices and experts). The main results of this study indicate that overall reliability of expert evaluations was 76% compared to 65% for evaluations produced by novices. The potential of the Structured Walkthrough method as a useful and viable tool for expert evaluators is also examined. Copyright 2014 ACM
Les sables de Fontainebleau: a natural quartz reference sample and its characterisation
Fundamental studies on luminescence production
in natural quartz require samples
which can be studied by groups of laboratories
using complementary methods. In the framework
of a European collaboration studying
quartz luminescence, a sample originating
from the Fontainebleau Sandstone Formation
in France was selected for characterisation
and distribution to establish a starting point
for interlaboratory work. Here we report on
the preparation and characterisation work
undertaken before distribution with the aim
of ensuring that each laboratory received
comparable material. Material was purified to
enrich the quartz concentration, followed by
mineralogical screening by SEM and ICP-MS
analyses. Luminescence screening measurements
were undertaken at a single laboratory
(SUERC) to verify the suitability of the sample
for use within the study, and to establish the
level of homogeneity of subsamples prepared
for distribution. The sample underwent minimal
non-chemical pre-treatment by multiple
cycles of magnetic separation and annealing.
SEM analysis showed that the sample
consists mainly of SiO2. The luminescence
characterisation confirmed a dose sensitivity
of ca. 22,000–160,000 cts K−1 Gy−1 per 260–
290 grains for the 110◦C UV TL peak, well
developed low (here: 100–300◦C) temperature
(pre-dose) TL signals and high OSL sensitivities.
The grain to grain OSL response varies by
more than one order of magnitude. No significant
IRSL signal was observed. In summary,
the results from luminescence characterisation
confirm the suitability of the sample for the
luminescence experiments envisaged and have
established a basis for comparability in studies
conducted by a network of laboratories
An elementary illustrated introduction to simplicial sets
This is an expository introduction to simplicial sets and simplicial homotopy
theory with particular focus on relating the combinatorial aspects of the
theory to their geometric/topological origins. It is intended to be accessible
to students familiar with just the fundamentals of algebraic topology.Comment: 57 pages, 32 figures. Further corrections and additions. Section 2
has been reorganized with new material added. Section 5.1 on Simplicial Hom
added. Hopefully final version. 10/3/16-Added errata section at end and made
minor correction
The social construction of meaning : Reading Animal Farm in the classroom
The novel, it has generally been assumed, was from its very beginnings a literary form designed to be read by solitary, silent individuals. One consequence of this assumption is that the class novel, read amid all the noise and sociality of the classroom, tends to be treated as a preparation formore authentic, private reading, or even as poor substitute for it. This essay argues that the history of novel-reading is more complicated and more varied than has been assumed; it goes on to explore, through the story of a single lesson, the possibilities for meaning-making that are the product of particular pedagogic practices as well as of the irreducibly social process of reading the class novel
Delivering the Maori-language newspapers on the Internet
Although any collection of historical newspapers provides a particularly rich and valuable record of events and social and political commentary, the content tends to be difficult to access and extremely time-consuming to browse or search. The advent of digital libraries has meant that for electronically stored text, full-text searching is now a tool readily available for researchers, or indeed anyone wishing to have asscess to specific information in text. Text in this form can be readily distributed via CD-ROM or the Internet, with a significant impact on accessibility over traditional microfiche or hard-copy distribution. For the majority of text being generated de nouveau, availability in electronic form is standard, and hence the increasing use of full-text search facilities. However, for legacy text available only in printed form, the provision of these electronic search tools is dependent on the prior electronic capture of digital facsimile images of the printed text, followed by the conversion of these images to electronic text through the process of optical character recognition (OCR). This article describes a project undertaken at the University of Waikato over the period 1999 to 2001 to produce a full-text searchable version of the Niupepa or Maori- language newspaper collection for delivery over the Internet
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