The stable Adams operations on Hermitian K-theory

We prove that exterior powers of (skew-)symmetric bundles induce a $\lambda$-ring structure on the ring $GW^0(X) \oplus GW^2(X)$, when $X$ is a scheme where $2$ is invertible. Using this structure, we define stable Adams operations on Hermitian $K$-theory. As a byproduct of our methods, we also compute the ternary laws associated to Hermitian $K$-theory

Unemployment: Getting the Questions Right - and some of the answers

This paper analyzes the issue of persistent high unemployment. It focuses on two channels of persistence. The first is capital accumulation. The paper analyzes investment decisions under imperfect competition, focusing in particular on the effects of demand and cost shocks on investment, capital composition and bankruptcies, and their effect on employment and unemployment. The second is labor supply. The paper analyzes the various channels through which the unemployed may become disenfranchised, leading to higher equilibrium unemployment. In both cases, it briefly reviews and assesses the available empirical evidence. It ends by drawing several implications.

Wage Bargaining and Unemployment Persistence

This paper looks at models of unemployment which make two central assumptions. The first is that wages are bargained between firms and employed workers, and that unemployment affects the outcome only to the extent that it affects the labor market prospects of either employed workers or of firms. The second is that the duration of unemployment affects either the search behavior or the skills of the unemployed, and/or the perceptions of firms of such skills. It argues that such models may explain riot only the evolution of European unemployment over the last two decades -an evolution which triggered their development, but many of the cyclical features of labor markets in general.

Validity of the one-dimensional limp model for porous materials

A straightforward criterion to determine the limp model validity for porous materials is addressed here. The limp model is an "equivalent fluid" model which gives a better description of the porous behavior than the well known "rigid frame" model. It is derived from the poroelastic Biot model assuming that the frame has no bulk stiffness. A criterion is proposed to identify the porous materials for which the limp model can be used. It relies on a new parameter, the Frame Stiffness Influence FSI based on porous material properties. The critical values of FSI under which the limp model can be used, are determined using a 1D analytical modeling for a specific boundary set: radiation of a vibrating plate covered by a porous layer.Comment: 12th International Student Conference on Electrical Engineering, Prague : Tch\`eque, R\'epublique (2008