990 resultados para Virtual elements
Resumo:
This paper introduces a novel interface designed to help blind and visually impaired people to explore and navigate on the Web. In contrast to traditionally used assistive tools, such as screen readers and magnifiers, the new interface employs a combination of both audio and haptic features to provide spatial and navigational information to users. The haptic features are presented via a low-cost force feedback mouse allowing blind people to interact with the Web, in a similar fashion to their sighted counterparts. The audio provides navigational and textual information through the use of non-speech sounds and synthesised speech. Interacting with the multimodal interface offers a novel experience to target users, especially to those with total blindness. A series of experiments have been conducted to ascertain the usability of the interface and compare its performance to that of a traditional screen reader. Results have shown the advantages that the new multimodal interface offers blind and visually impaired people. This includes the enhanced perception of the spatial layout of Web pages, and navigation towards elements on a page. Certain issues regarding the design of the haptic and audio features raised in the evaluation are discussed and presented in terms of recommendations for future work.
Resumo:
Background and purpose: Radiotherapy is widely used to palliate local symptoms in non-small-cell lung cancer. Using conventional X-ray simulation, it is often difficult to accurately localize the extent of the tumour. We report a randomized, double blind trial comparing target localization with conventional and virtual simulation.Methods: Eighty-six patients underwent both conventional and virtual simulation. The conventional simulator films were compared with digitally reconstructed radiographs (DRRs) produced from the computed tomography (CT) data. The treatment fields defined by the clinicians using each modality were compared in terms of field area, position and the implications for target coverage.Results: Comparing fields defined by each study arm, there was a major mis-match in coverage between fields in 66.2% of cases, and a complete match in only 5.2% of cases. In 82.4% of cases, conventional simulator fields were larger (mean 24.5+/-5.1% (95% confidence interval)) than CT-localized fields, potentially contributing to a mean target under-coverage of 16.4+/-3.5% and normal tissue over-coverage of 25.4+/-4.2%.Conclusions: CT localization and virtual simulation allow more accurate definition of the target volume. This could enable a reduction in geographical misses, while also reducing treatment-related toxicity.
Resumo:
This paper discusses the calculation of electron impact collision strengths and effective collision strengths for iron peak elements of importance in the analysis of many astronomical and laboratory spectra. It commences with a brief overview of R-matrix theory which is the basis of computer programs which have been widely used to calculate the relevant atomic data used in this analysis. A summary is then given of calculations carried out over the last 20 y for electron collisions with Fe II. The grand challenge, represented by the calculation of accurate collision strengths and effective collision strengths for this ion, is then discussed. A new parallel R-matrix program PRMAT, which is being developed to meet this challenge, is then described and results of recent calculations, using this program to determine optically forbidden transitions in e- – Ni IV on a Cray T3E-1200 parallel supercomputer, are presented. The implications of this e- – Ni IV calculation for the determination of accurate data from an isoelectronic e- – Fe II calculation are discussed and finally some future directions of research are reviewed.
Resumo:
Background and purpose: Currently, optimal use of virtual simulation for all treatment sites is not entirely clear. This study presents data to identify specific patient groups for whom conventional simulation may be completely eliminated and replaced by virtual simulation. Sampling and method: Two hundred and sixty patients were recruited from four treatment sites (head and neck, breast, pelvis, and thorax). Patients were randomly assigned to be treated using the usual treatment process involving conventional simulation, or a treatment process differing only in the replacement of conventional plan verification with virtual verification. Data were collected on set-up accuracy at verification, and the number of unsatisfactory verifications requiring a return to the conventional simulator. A micro-economic costing analysis was also undertaken, whereby data for each treatment process episode were also collected: number and grade of staff present, and the time for each treatment episode. Results: The study shows no statistically significant difference in the number of returns to the conventional simulator for each site and study arm. Image registration data show similar quality of verification for each study arm. The micro-costing data show no statistical difference between the virtual and conventional simulation processes. Conclusions: At our institution, virtual simulation including virtual verification for the sites investigated presents no disadvantage compared to conventional simulation.
Resumo:
In this paper we discuss collaborative learning strategies based on the use of digital stories in corporate training and lifelong learning. The text starts with a concise review on theoretical and technical foundations about the use of digital technologies in collaborative strategies in lifelong learning. We will also discuss if the corporate training may be improved by the use of individual audio-visual experience in learning process. Careful planning, scripting and production of audio-visual digital stories can help in the construction of collaborative learning spaces in which adults are in the context of vocational training throughout life. Our analysis concludes emphasizing on the need to experience the routing performance of digital stories in the context of corporate training, following the reference levels mentioned here, so we can have in a future more theoretical and empirical elements for the validation and conceptualization in the use of digital stories in the context of corporate training. Ultimately we believe that lifelong learning can be improved with the use of strategies that promote the production of personal audio-visual for those involved in teaching and learning process in organizational context.
Resumo:
The transformation of the Information and Communication Technologies (ICT) into knowledge and learning technologies is increasingly becoming a matter of concern. Teaching settings associated with the use of blogs in Higher Education are presented in this paper, proceeding from an innovative learning experience of projects carried out by a group of professors between 2009 and 2013. Both, teachers and students who took part in the subjects that implemented the blog, considered it as helpful resource to create a virtual and learning-teaching environment due to the multiple potentialities it offers. Among some of these potentialities, some stand out: it makes easier the access to knowledge, promotes a more active and reflective learning, expands the social experience of learning, provides evidence about the students’ progress which helps to reorient the teaching-learning process, and encourages the critical judgment. Nevertheless, several problems related with the students’ participation and the teacher’s blog management have been identified.