Measuring distributions of jump rates in disordered metal–hydrogen systems by nuclear magnetic relaxation

Monte Carlo calculations of the nuclear magnetic relaxation rate in a disordered metal–hydrogen system having a distribution of jump rates are reported. The calculations deal specifically with the spin-locked rotating-frame relaxation time T1ρ. The results demonstrate that the temperature variation of the rate is only weakly dependent on the distribution and it is therefore unlikely that the jump rate distribution can be extracted from relaxation measurements in which temperature is the main variable. It is shown that the alternative of measuring the relaxation rate over a wide range of spin-locking field strengths at a constant temperature can lead to an evaluation of the distribution.

Birth-death processes with mass annihilation and state-dependent immigration

A birth-death process is subject to mass annihilation at rate β with subsequent mass immigration occurring into state j at rateα j . This structure enables the process to jump from one sector of state space to another one (via state 0) with transition rate independent of population size. First, we highlight the difficulties encountered when using standard techniques to construct both time-dependent and equilibrium probabilities. Then we show how to overcome such analytic difficulties by means of a tool developed in Chen and Renshaw (1990, 1993b); this approach is applicable to many processes whose underlying generator on E\{0} has known probability structure. Here we demonstrate the technique through application to the linear birth-death generator on which is superimposed an annihilation/immigration process.

Thermoelectric MHD effects on equiaxed crystal morphology

The effects of a constant uniform magnetic field on a growing equiaxed crystal are investigated using a 3-dimensional enthalpy based numerical model. Two cases are considered: The first case looks at unconstrained growth, where the current density is generated through the thermo-electric effect and the current circulates between the tips and roots of the dendrite, the second represents an imposed potential difference across the domain. A jump in the electrical conductivity between the liquid and solid causes the current density to be non uniform. In both cases the resulting Lorentz force drives fluid flow in the liquid phase, this in turn causes advection of the thermal and solute field altering the free energy close to the interface and changing the morphology of the dendrite. In the first case the flow field is complex comprising of many circulations, the morphological changes are modelled using a 2D model with a quasi 3D approximation. The second case is comparable to classic problems involving a constant velocity boundary.

Exploration of the student experience of e-learning: beginning to bridge the learning divide

Introduction This proposal aims, through debate within symposium to explore the student experience of e-learning. The team facilitating the discussion will draw upon their experience of an HEA funded pathfinder project, the main aim of which was to collect learner stories about their experience of using technology in their everyday learning activities at the University of Greenwich across a range of programmes, levels, locations and student groups. Method The project design responded to the growing body of student voice literature and then utilised and built upon the JISC-funded studies that focussed on understanding the learner perspectives on the role of technology in learning, namely: • the LEX study which investigated a broad spectrum of technology use by eliciting rich data about learners’ feelings, beliefs and intentions towards e-learning (Creanor et al, 2006); • the LXP studies which explored disciplinary differences in uses of technology by university students through a variety of methodologies (Conole et al, 2006). Results The symposium will be organised as a round table discussion that will be structured into three sections: • Designing an online survey tool, and the results of our survey. • Exploring student stories. • What can learned from the project and taking the findings back to enhance learning. To stimulate discussion each section will start by asking the participants to discuss and debate a particular question, this will be followed by an interactive presentation by the respective member of the project team who will share the findings of the project and invite contributions to the resulting discussion from personal perspectives. The questions are: • What is effective learning within a context of digital technology? • What are the myths and truths about the identity of today's learners? • What practical changes need to happen in order to see real change? Conclusion The final section of the symposium will invite contributions from the participants in order to collate the views and perspectives of all the participants in order to focus the discussion on the following: • The issues that have arisen as a result of the round table debates. • New speculative approaches to enhancing the student experience. • A controversial stand to the future of Higher Education teaching and learning and the role and integration of technology within that education. The symposium will provide an opportunity to explore the predictive value of Student Experience of E-Learning Laboratory (SEEL) project.

The Students' Experience of E-learning

The Student Experience of E-learning Laboratory (SEEL) is a three year initiative that seeks to develop the University’s capacity to discover more about the impact of e-learning on our students in an attempt to narrow the gap between the digital natives and immigrants (Prensky, 2001). In its first year the project team have gathered data on the student experience of using technology in support of their learning from across the University. Initial analysis suggests we should listen more carefully to our students and may need to review some of our current practices in relation to e-learning and explore some new ways of working. In this workshop we will outline some of the findings and consider implications for our future practice.

Making the link: a customised social networking site can foster learning

Thanks to the internet, students today can do things that students of the past could not. They can learn formally or informally by interacting on social networking sites in a way that is not easily accomplished in a lecture theatre or classroom.

Experts on e-learning: insights gained from listening to the student voice!

The Student Experience of e-Learning Laboratory (SEEL) project at the University of Greenwich was designed to explore and then implement a number of approaches to investigate learners’ experiences of using technology to support their learning. In this paper members of the SEEL team present initial findings from a University-wide survey of nearly a 1000 students. A selection of 90 ‘cameos’, drawn from the survey data, offer further insights into personal perceptions of e-learning and illustrate the diversity of students experiences. The cameos provide a more coherent picture of individual student experience based on the totality of each person’s responses to the questionnaire. Finally, extracts from follow-up case studies, based on interviews with a small number of students, allow us to ‘hear’ the student voice more clearly. Issues arising from an analysis of the data include student preferences for communication and social networking tools, views on the ‘smartness’ of their tutors’ uses of technology and perceptions of the value of e-learning. A primary finding and the focus of this paper, is that students effectively arrive at their own individualised selection, configuration and use of technologies and software that meets their perceived needs. This ‘personalisation’ does not imply that such configurations are the most efficient, nor does it automatically suggest that effective learning is occurring. SEEL reminds us that learners are individuals, who approach learning both with and without technology in their own distinctive ways. Hearing, understanding and responding to the student voice is fundamental in maximising learning effectiveness. Institutions should consider actively developing the capacity of academic staff to advise students on the usefulness of particular online tools and resources in support of learning and consider the potential benefits of building on what students already use in their everyday lives. Given the widespread perception that students tend to be ‘digital natives’ and academic staff ‘digital immigrants’ (Prensky, 2001), this could represent a considerable cultural challenge.

An analysis of masculine and feminine writings in postings within a series of health and social care online undergraduate courses

This study aims to extend understanding of pedagogic dialogue by analysing the effect that the gender of the student has on interaction within a selection of ordinary health and social care on line courses.

Kinematics and EMG analysis of expert pole vaulter's lower limb during take off phase (P218)

Introduction: The critical phase, in jumping events in track and field, appears to be between touchdown and take-off. Since obvious similarities exist between the take off phase in both long jump and pole vault, numerous 3D kinematics and electromyographic studies have only looked at long jump. Currently there are few detailed kinematics electromyographic data on the pole vault take-off phase. The aim of this study was therefore to characterise kinematics and electromyographic variables during the take-off phase to provide a better understanding of this phase in pole vaulting and its role in performance outcome. Material and methods: Six pole-vaulters took part in the study. Kinematics data were captured with retro reflective markers fixed on the body. Hip, knee and ankle angle were calculated. Differential bipolar surface electrodes were placed on the following muscles of the take-off leg: tibialis anterior, lateral gastrocnemius, vastus lateralis, rectus femoris, bicep femoris and gluteus maximus. EMG activity was synchronously acquired with the kinematic data. EMG data were rectified and smoothed using a second order low pass Butterworth Bidirectional filter (resulting in a 4th order filter) with a cut-off frequency of 14 Hz. Results: Evolution of hip, knee and ankle angle show no significant differences during the last step before touchdown, the take-off phase and the beginning of fly phase. Meanwhile, strong differences in EMG signal are noted inter and intra pole vaulter. However for a same subject the EMG activities seem to converge to some phase locked point. Discussion: All pole vaulters have approximately the same visible coordination This coordination reflects a different muscular control among pole vaulters but also for a considered pole vaulter. These phase locked point could be considered as invariant of motor control i.e. a prerequisite for a normal sequence of the movement and performance realization.