A Reflective Evaluation of Group Assessment

There is a general agreement in the literature that groupwork helps to develop important interpersonal and personal skills (Race, 2001; Visram & Joy, 2003; Elliot & Higgins, 2005; Kench et al, 2008). However, one of the problems with groupwork for both students and lecturers is how the work should be assessed (Parsons & Kassabova, 2002). The possibility of having ‘free-riders’ and the difficulty of fairly awarding marks to reflect the level of students’ contribution to a group output are some of the key problem areas in groupwork assessment (Race, 2001). Peer assessment is seen as one of the methods to deal with these problems. It can generally involve students assessing each other’s level of contribution to the group’s output (Visram & Joy, 2003). This paper provides our reflection on the use of peer assessment on a student group project

Using evidence to inform health policy: case study

No abstract available

Vector wind profile gust model

The development of a vector wind gust model that is suitable for orbital flight test operations and trade studies was studied. Verification of the hypothesis that gust component variables are gamma distributed, gust modulus is approximately Weibull distributed, and zonal and meridional gust components are bivariate gamma distributed is emphasized. A method of testing for bivariate gamma distributed variables, and two distributions for gust modulus are described. The results of extensive hypothesis testing of one of the distributions are presented, and the validity of the gamma distribution for representation of gust component variables is established

The importance of the classical channel in the impurity transport of optimized stellarators

In toroidal magnetic confinement devices, such as tokamaks and stellarators, neoclassical transport is usually an order of magnitude larger than its classical counterpart. However, when a high-collisionality species is present in a stellarator optimized for low Pfirsch-Schl\"uter current, its classical transport can be comparable to the neoclassical transport. In this letter, we compare neoclassical and classical fluxes and transport coefficients calculated for Wendelstein 7-X (W7-X) and Large Helical Device (LHD) cases. In W7-X, we find that the classical transport of a collisional impurity is comparable to the neoclassical transport for all radii, while it is negligible in the LHD cases, except in the vicinity of radii where the neoclassical transport changes sign. In the LHD case, electrostatic potential variations on the flux-surface significantly enhance the neoclassical impurity transport, while the classical transport is largely insensitive to this effect in the cases studied.Comment: 10 pages, 2 figure

Evaluating the impact of embodied conversational agents (ECAs) attentional behaviors on user retention of cultural content in a simulated mobile environment

The paper presents an evaluation study of the impact of an ECA’s attentional behaviors using a custom research method that combines facial expression analysis, eye-tracking and a retention test. The method provides additional channels to EEG-based methods for the study of user attention and emotions. In order to validate the proposed approach, two tour guide applications were created with an embodied conversational agent(ECA) that presents cultural content about a real-tourist attraction. The agent simulates two attention-grabbing mechanisms - humorous and serious to attract the users’ attention. A formal study was conducted to compare two tour guide applications in the lab. The data collected from the facial expression analysis and eye-tracking helped to explain particularly good and bad performances in retention tests. In terms of the study results, strong quantitative and qualitative evidence was found that an ECA should not attract more attention to itself than necessary, to avoid becoming a distraction from the flow of the content. It was also found that the ECA had an inverse effect on the retention performance of participants with different gender and their use on computer interfaces is not a good idea for elderly users

Evaluating an intelligent Q&A system for mobile cultural learning

The paper presents a user study designed to evaluate the impact of an intelligent Q&A system for mobile cultural learning on the user’s subjective impressions and retention performance. We have chosen a recent pedagogical framework for mobile learning as a theoretical foundation for this work and designed our system accordingly. In particular, our Q&A system enables individual learners to interact with unknown cultural content under simulated mobile conditions in a well-organised and structured manner using natural language. To investigate the impact of the Q&A system on the participants’ retention of cultural content, we compared two variations of the Q&A system in the lab under simulated mobile conditions. The systems differed both in terms of the approach for processing natural language and style of a Q&A session. Below, we present the results of the study and a series of design recommendations that should aid in the development of more robust Q&A models for mobile cultural systems

An empirical study on the effects of embodied conversational agents on user retention performance and perception in a simulated mobile environment

The paper presents a user study designed to examine the impact of the presence of a multimodal ECA on the user’s ability to retain content of cultural value with variable degree of difficulty (i.e., technical and simple content). The study was conducted in the lab, using a high resolution panorama representing four locations in an archaeological attraction. The content participants perceived differed both in terms of complexity and length. Participants interacted with an ECA-based system and then with a non-ECA system that provided content about popular locations in the attraction. Results indicate that participants who used the system with the ECA retained content of variable difficulty more consistently, than those who used the system without the ECA. However, we also found that if text is added as an additional output modality to an ECA-based information system it can positively impact the perception of the technical content, which can potentially lead to enhanced retention of technical content

Waveguide containing a backward-wave slab

We have considered theoretically the waveguide properties of a plane two-layered waveguide, whose one layer is a usual magnetodielectric (forward-wave medium), but another one is a slab of so-called backward-wave material (BW-material), whose both permittivity and permeability are negative. We have analyzed the properties of eigenwaves in this waveguide. In particular, it was found that there exist waves of both TE and TM polarizations, whose fields decay exponentially from the interface of the two slabs inside both layers, and their slow-wave factor tends to infinity at small frequencies. Thus, this waveguiding system supports super-slow waves with extremely short wavelengthes, as compared to the free-space wavelength and the cross section size. Other peculiarities of the spectrum are also discussed