19 research outputs found
Experiences of using an interactive audience response system in lectures
BACKGROUND: Lectures are good for presenting information and providing explanations, but because they lack active participation they have been neglected. METHODS: Students' experiences were evaluated after exposing them to the use of voting during lectures in their paediatrics course. Questions were delivered to the students taking paediatrics course. Thirty-six students out of the total of 40 (90%) attended the opening lecture, at which the first survey concerning previous experiences of lectures was performed. Thirty-nine students (98%) answered the second series of questions at the end of the paediatrics course. RESULTS: Most of the students felt that voting improved their activity during lectures, enhanced their learning, and that it was easier to make questions during lectures than earlier. CONCLUSIONS: The students gained new, exciting insights much more often during the paediatrics course than before. We as teachers found that voting during lectures could easily overcome some of the obstacles of good lecturing
Estimation of hydraulic conductivity and its uncertainty from grain-size data using GLUE and artificial neural networks
peer reviewedaudience: researcher, professionalVarious approaches exist to relate saturated hydraulic conductivity (Ks) to grain-size data. Most methods use a single grain-size parameter and hence omit the information encompassed by the entire grain-size distribution. This study compares two data-driven modelling methods, i.e.multiple linear regression and artificial neural networks, that use the entire grain-size distribution data as input for Ks prediction. Besides the predictive capacity of the methods, the uncertainty associated with the model predictions is also evaluated, since such information is important for stochastic groundwater flow and contaminant transport modelling.
Artificial neural networks (ANNs) are combined with a generalized likelihood uncertainty estimation (GLUE) approach to predict Ks from grain-size data. The resulting GLUE-ANN hydraulic conductivity predictions and associated uncertainty estimates are compared with those obtained from the multiple linear regression models by a leave-one-out cross-validation. The GLUE-ANN ensemble prediction proved to be slightly better than multiple linear regression. The prediction uncertainty, however, was reduced by half an order of magnitude on average, and decreased at most by an order of magnitude. This demonstrates that the proposed method outperforms classical data-driven modelling techniques. Moreover, a comparison with methods from literature demonstrates the importance of site specific calibration.
The dataset used for this purpose originates mainly from unconsolidated sandy sediments of the Neogene aquifer, northern Belgium. The proposed predictive models are developed for 173 grain-size -Ks pairs. Finally, an application with the optimized models is presented for a borehole lacking Ks data
Selective Exposure to Berita Harian Online and Utusan Malaysia Online: The Roles of Surveillance Motivation, Website Usability and Website Attractiveness
News media allows audiences to be selective in determining both their news sources
and type of news stories they read. This study examined factors influencing selective
exposure to the online editions of two mainstream Malaysian newspapers, Berita
Harian and Utusan Malaysia. Using selective exposure theory as the theoretical
lens, this study compared both newspapers in terms of their audiences’ level of
surveillance motivation, and how audiences rate the newspapers’ websites with respect
to usability and attractiveness. This study used a within-subject experimental research
design that exposed 51 subjects to both Berita Harian and Utusan Malaysia online
newspapers. The results of the experiment indicate that Berita Harian and Utusan
Malaysia online were significantly different in terms of website usability; however,
no significant differences were found in terms of surveillance motivation or website
attractiveness between the two newspapers. Further analysis indicate that the only
significant predictor of selective exposure was website usability. This study highlights
the importance of website usability for online newspapers wanting to harness audience
selectivity