Generalized Futaki Invariant of Almost Fano Toric Varieties, Examples

The interpretation, due to T. Mabuchi, of the classical Futaki invariant of Fano toric manifolds is extended to the case of the Generalized Futaki invariant, introduced by W. Ding and G. Tian, of almost Fano toric varieties. As an application it is shown that the real part of the Generalized Futaki invariant is positive for all degenerations of the Fano manifold V_{38}, obtained by intersection of the Veronese embedding of ${\bf P}^3\times{\bf P}^2 \subset {\bf P}^{11}$ with codimension-two hyperplanes.Comment: 22 pages, LaTeX2

Specialisation : pro and anti-globalizing 1990-2002

Specialization alters the incidence of trade costs to buyers and sellers, with pro-and anti-globalizing effects on 76 countries from 1990-2002. The structural gravity model yields measures of Constructed Home Bias and the Total Factor Productivity effect of changing incidence. A bit more than half the world's countries experience declining constructed home bias and rising real output while the remainder of countries experi- ence rising home bias and falling real output. The effects are big for the outliers. A novel test of the structural gravity model restrictions shows it comes very close in an economic sense

Nadel's Subschemes of Fano Manifolds X with a Picard Group Pic(X) Isomorphic to Z

∗The author supported by Contract NSFR MM 402/1994.In this paper we find a global sufficient condition for suitable subschemes of Fano manifolds to be Nadel’s subschemes. We apply this condition to one-dimensional subschemes of a projective space

Gold Standard Gravity

This paper provides striking confirmation of the restrictions of the structural gravity model of trade. Structural forces predicted by theory explain 95% of the variation of the fixed effects used to control for them in the recent gravity literature, fixed effects that in principle could reflect other forces. This validation opens avenues to inferring unobserved sectoral activity and multilateral resistance variables by equating fixed effects with structural gravity counterparts. Our findings also provide important validation of a host of general equilibrium comparative static exercises based on the structural gravity model.

A Lagrange multiplier method for a Stokes-Biot fluid-poroelastic structure interaction model

We study a finite element computational model for solving the coupled problem arising in the interaction between a free fluid and a fluid in a poroelastic medium. The free fluid is governed by the Stokes equations, while the flow in the poroelastic medium is modeled using the Biot poroelasticity system. Equilibrium and kinematic conditions are imposed on the interface. A mixed Darcy formulation is employed, resulting in continuity of flux condition of essential type. A Lagrange multiplier method is employed to impose weakly this condition. A stability and error analysis is performed for the semi-discrete continuous-in-time and the fully discrete formulations. A series of numerical experiments is presented to confirm the theoretical convergence rates and to study the applicability of the method to modeling physical phenomena and the sensitivity of the model with respect to its parameters