This paper describes the methodology and procedures of international comparisons of productivity levels for twelve manufacturing industries (producing food products, beer, soap and detergents, iron and steel, machine tools, various types of machinery, computers, audio and video equipment, industrial electronics, wired communication equipment, passenger cars and car components) between Germany, Japan and the United States. These estimates ...

This paper presents a new preconditioning technique for solving linear systems. It is based on an invariant subspace approximation for the restarted GMRES algorithm. It uses the flexible GMRES scheme by designing a new preconditioning after each restart. Numerical examples show that this approach may converge almost as fast as full-GMRES at a, possibly, much lower cost.

The dynamics of circuits in power electronics may often be modelled by means of systems of linear differential equations with piecewise constant coefficients and sinusoidal inhomogeneities. The Static Var (Volt-Ampere reactive) Compensator (SVC, a device for power network control) is a representative example. Initial value problems of this type may be handled by means of the matrix exponential, whereas the construction of periodic solutions ...

In this paper identities are derived which allow to compute the Coulomb energy associated with emN/em charges in a central cell and all their periodic images. These identities are all consequences of one basic identity which is obtained in a simple and straightforward way. It is possible to extend the results to other types of potentials as well.