Specimen generation approaches for DEM simulations.

Discrete Element Method (DEM) simulations ofelement tests cam provide significant insight into the micro-mechanics of soil response. It is well established that soil behaviour is strongly dependant on the initial density. Generation of particulate assemblies for three-dimensional DEM analyses must therefore allow for void ratio control. In this paper, different specimen generation approaches for DEM analyses are discussed. A methodology for the generation of assemblies of spherical particles with a specified initial density and stress state is presented. The effects of the different preparation methods on the specimen fabric are then considered in detail. For isotropic consolidation, it is shown that varying the coefficient of inter-particle friction allows control of the specimen void ratio at a specified confining stress. Simulations of anisotropic consolidation, from an initial isotropic stress state, to a final state where sigma(3) = K(0)sigma(1) indicated that the specimen void ratio and fabric are relatively insensitive to the intermediate stress path, provided an intermediate stress along the K(0) line was attained.

The perceptions of postgraduate international students of examinations.

The increasing internationalisation of higher education means that many students in the UK are not native English speakers, possibly putting them at a disadvantage in an examination environment. However, exams continue to be used even though although they are often deprecated as an assessment instrument in postgraduate courses. This article explores the implications from these observations for module leaders and for higher education institutions. Three themes emerge: the impact of internationalisation, the use of exams at postgraduate level and the language and cultural issues faced by international students. A review of university policy and quality documents revealed a general commitment to internationalisation but some gaps in policy support, for students with English as a second or foreign language. A survey of students in two computing programmes evaluated these themes. The results did not show up any major issues, though there were a number of suggestions to improve the exam process to address feelings of bias to UK or native-English-speaking students. The research therefore established that the university’s internationalisation and diversity strategy is broadly reflected in students’ experiences, with the possible exception of students who were recruited with insufficient English to be able to engage successfully with the material. The contrast in responses when analysed by home country or English proficiency suggest that Learning, Teaching and Assessment (LTA) practice in this context should be clear whether and when language or culture are the main barrier to students. Pragmatic recommendations are made for improvement in examination practice, and to assessment processes generally in this context. Areas for further work are identified.