Monetary targeting in practice : the German experience

From the mid-seventies on, the central banks of most major industrial countries switched to monetary targeting. The Bundesbank was the first central bank to take this step, making the switch at the end of 1974. This changeover to monetary targeting was due to the difficulties which the Bundesbank - like other central banks - was facing in pursuing its original strategy, and whichcame to a head in the early seventies, when inflation escalated. A second factor was the collapse of the Bretton Woods system of fixed exchange rates, which created the necessary scope for national monetary targeting. Finally, the advance of monetarist ideas fostered the explicit turn towards monetary targets, although the Bundesbank did not implement these in a mechanistic way. Whereas the Bundesbank has adhered to its policy of monetary targeting up to the present, nowadays monetary targeting plays only a minor role worldwide. Many central banks have switched to the strategy of direct inflation targeting. Others favour a more discretionary approach or a policy which is geared to the exchange rate. In the academic debate, monetary targeting is often presented as an outdated approach which has long since lost its basis of stable money demand. These findings give riseto a number of questions: Has monetary targeting actually become outdated? Which role is played by the concrete design of this strategy, and, against this background, how easily can it be transferred to European monetary union? This paper aims to answer these questions, drawing on the particular experience which the Bundesbank has gained of monetary targeting. It seems appropriate to discuss monetary targeting by using a specific example, since this notion is not very precise. This applies, for example, to the money definition used, the way the target is derived, the stringency applied in pursuing the target and the monetary management procedure

Structural models and structural change: analytical principles and methodological issues

Structural analysis is the main topic of this paper and structural change is a dominant theme of the present work. The analysis of structural models and of theories of structural changes carried out in this paper has a double meaning. On the one hand, it allows to pick up several essential principles that characterize these models, on the other hand, it should allow us to reconsider some important methodological issues under a new light, such as different methods of decomposition of the productive systems, the problem of complexity and the strategies to reduce complexity. Moreover, the paper tries to compare Quesnay’s Tableau, taken as a benchmark model, with Leontief’s, von Neumann’s and Sraffa’s models to pick up the different features of these models with respect to his theoretical framework and also to identify their characteristics for structural analysis and structural change.

Generalized thick strip modelling for vortex-induced vibration of long flexible cylinders

We propose a generalized strip modelling method that is computationally efficient for the VIV prediction of long flexible cylinders in three-dimensional incompressible flow. In order to overcome the shortcomings of conventional strip-theory-based 2D models, the fluid domain is divided into “thick” strips, which are sufficiently thick to locally resolve the small scale turbulence effects and three dimensionality of the flow around the cylinder. An attractive feature of the model is that we independently construct a three-dimensional scale resolving model for individual strips, which have local spanwise scale along the cylinder's axial direction and are only coupled through the structural model of the cylinder. Therefore, this approach is able to cover the full spectrum for fully resolved 3D modelling to 2D strip theory. The connection between these strips is achieved through the calculation of a tensioned beam equation, which is used to represent the dynamics of the flexible body. In the limit, however, a single “thick” strip would fill the full 3D domain. A parallel Fourier spectral/hp element method is employed to solve the 3D flow dynamics in the strip-domain, and then the VIV response prediction is achieved through the strip-structure interactions. Numerical tests on both laminar and turbulent flows as well as the comparison against the fully resolved DNS are presented to demonstrate the applicability of this approach

Substructured formulations of nonlinear structure problems - influence of the interface condition

We investigate the use of non-overlapping domain decomposition (DD) methods for nonlinear structure problems. The classic techniques would combine a global Newton solver with a linear DD solver for the tangent systems. We propose a framework where we can swap Newton and DD, so that we solve independent nonlinear problems for each substructure and linear condensed interface problems. The objective is to decrease the number of communications between subdomains and to improve parallelism. Depending on the interface condition, we derive several formulations which are not equivalent, contrarily to the linear case. Primal, dual and mixed variants are described and assessed on a simple plasticity problem.Comment: in International Journal for Numerical Methods in Engineering, Wiley, 201

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