Higher-order surface FEM for incompressible Navier-Stokes flows on manifolds

Stationary and instationary Stokes and Navier-Stokes flows are considered on two-dimensional manifolds, i.e., on curved surfaces in three dimensions. The higher-order surface FEM is used for the approximation of the geometry, velocities, pressure, and Lagrange multiplier to enforce tangential velocities. Individual element orders are employed for these various fields. Stream-line upwind stabilization is employed for flows at high Reynolds numbers. Applications are presented which extend classical benchmark test cases from flat domains to general manifolds. Highly accurate solutions are obtained and higher-order convergence rates are confirmed.Comment: Submitted to International Journal for Numerical Methods in Fluids V1: Initial submission V2: Corrected errors in strong forms, revised discussion of the result

Sharing Global Governance: The Role of Civil Society Organizations

This report explores the multiple roles and potential of CSOs in international policymaking and examines the strengths and weaknesses of CSOs and state-based organizations in global governance. It looks particularly closely at the resources, access, skills and experience that each group of actors brings to the table. It concludes that the infrastructure used to incorporate CSOs into the United Nations and other multilaterals must be strengthened and expanded if more integrated and effective forms of collaboration are to be developed and outlines policy recommendations how this goal can be accomplished

Fast Isogeometric Boundary Element Method based on Independent Field Approximation

An isogeometric boundary element method for problems in elasticity is presented, which is based on an independent approximation for the geometry, traction and displacement field. This enables a flexible choice of refinement strategies, permits an efficient evaluation of geometry related information, a mixed collocation scheme which deals with discontinuous tractions along non-smooth boundaries and a significant reduction of the right hand side of the system of equations for common boundary conditions. All these benefits are achieved without any loss of accuracy compared to conventional isogeometric formulations. The system matrices are approximated by means of hierarchical matrices to reduce the computational complexity for large scale analysis. For the required geometrical bisection of the domain, a strategy for the evaluation of bounding boxes containing the supports of NURBS basis functions is presented. The versatility and accuracy of the proposed methodology is demonstrated by convergence studies showing optimal rates and real world examples in two and three dimensions.Comment: 32 pages, 27 figure

Charles C. Fries, linguistics and corpus linguistics

Halliday has long claimed that information concerning the relative frequencies of the various options within a system should be considered part of the system itself. Such a position entails that linguists have some basis for describing these frequencies. Hence SFL has made considerable use of corpora and of corpus linguistics. Of course, the field of corpus linguistics is commonly regarded as a brand new approach to linguistics which has developed and become popular over the past forty years—since the development of computers. Like all new fields, however, its roots lie in earlier forms of the discipline. This paper addresses one of the forebears of this field, Charles C. Fries. He thought of himself simply as a linguist (not a corpus linguist), yet his theory and practice have much in common with current versions of corpus linguistics and SFL