Modified alternating direction methods for solving a two-dimensional non-continuous seepage flow with fractional derivatives

In this paper, a two-dimensional non-continuous seepage flow with fractional derivatives (2D-NCSF-FD) in uniform media is considered, which has modified the well known Darcy law. Using the relationship between Riemann-Liouville and Grunwald-Letnikov fractional derivatives, two modified alternating direction methods: a modified alternating direction implicit Euler method and a modified Peaceman-Rachford method, are proposed for solving the 2D-NCSF-FD in uniform media. The stability and consistency, thus convergence of the two methods in a bounded domain are discussed. Finally, numerical results are given.

A mass-conservative control volume-finite element method for solving Richards’ equation in heterogeneous porous media

We present a mass-conservative vertex-centred finite volume method for efficiently solving the mixed form of Richards’ equation in heterogeneous porous media. The spatial discretisation is particularly well-suited to heterogeneous media because it produces consistent flux approximations at quadrature points where material properties are continuous. Combined with the method of lines, the spatial discretisation gives a set of differential algebraic equations amenable to solution using higher-order implicit solvers. We investigate the solution of the mixed form using a Jacobian-free inexact Newton solver, which requires the solution of an extra variable for each node in the mesh compared to the pressure-head form. By exploiting the structure of the Jacobian for the mixed form, the size of the preconditioner is reduced to that for the pressure-head form, and there is minimal computational overhead for solving the mixed form. The proposed formulation is tested on two challenging test problems. The solutions from the new formulation offer conservation of mass at least one order of magnitude more accurate than a pressure head formulation, and the higher-order temporal integration significantly improves both the mass balance and computational efficiency of the solution.

Narrative, education policy and the newsprint media : A critical discourse analysis of the construction of young people's participation in education or employment

This thesis used Critical Discourse Analysis to investigate how a government policy and the newsprint media constructed discussion about young people’s participation in education or employment. The study found that a continuous narrative across both sites about government as a noble agent taking action to redress the social disruption caused by young people’s disengagement. Unlike the education policy, the newsprint media blamed young people who were disengaged and failed to recognise the barriers they often face. The study points to possibilities for utilising the power of narrative to build a more fair and rigorous discussion of issues in the public sphere.

New media and the transformation of higher education

One set of public institutions that has seen growing discussion about the transformative impact of new media technologies has been universities. The higher education sector, historically one of the more venerable and stable areas of public life, is now the subject of almost continuous speculation about whether it can continue in its current form during the 21st century. Digital media technologies are often seen as being at the forefront of such changes. It has been widely noted that moves towards a knowledge economy generates ‘skills-biased technological change’, that places a premium upon higher education qualifications, and that this earnings gap remains despite the continuing increase in the number of university graduates. As the demand for higher education continues to grow worldwide, there are new discussions about whether technologically-mediated education through new forms such as Massively Open Online Courses (MOOCs) are broadening access to quality learning, or severing the vital connection between teacher and student seen as integral to the learning process. This paper critically appraises such debates in the context of early 21st century higher education. It will discuss ten drivers of change in higher education, many of which are related to themes discussed elsewhere in this book, such as the impact of social media, globalization, and a knowledge economy. It will also consider the issues raised in navigating such developments from the perspective of the ‘Five P’s’: practical issues; personal issues; pedagogical issues; policy issues; and philosophical issues. It also includes a critical evaluation of MOOCs from the point of view of their educational qualities. It will conclude with the observation that while universities will continue to play a significant – and perhaps growing – role in the economy, society and culture, the issues raised about what Clayton Christensen and Henry Eyring term the ‘disruptive university’ (Christensen and Eyring 2011) are nonetheless pressing ones, and that cost and policy pressures in particular are likely to generate significant institutional transformations in higher education worldwide.

A second order control-volume finite-element least-squares strategy for simulating diffusion in strongly anisotropic media

An unstructured mesh �nite volume discretisation method for simulating di�usion in anisotropic media in two-dimensional space is discussed. This technique is considered as an extension of the fully implicit hybrid control-volume �nite-element method and it retains the local continuity of the ux at the control volume faces. A least squares function recon- struction technique together with a new ux decomposition strategy is used to obtain an accurate ux approximation at the control volume face, ensuring that the overall accuracy of the spatial discretisation maintains second order. This paper highlights that the new technique coincides with the traditional shape function technique when the correction term is neglected and that it signi�cantly increases the accuracy of the previous linear scheme on coarse meshes when applied to media that exhibit very strong to extreme anisotropy ratios. It is concluded that the method can be used on both regular and irregular meshes, and appears independent of the mesh quality.