There are various concepts of structure preserving mappings in geometry. It is the aim of the present paper to give a survey on geometrical characterizations of some of those mappings. We discuss the results for projective spaces in some detail and report on generalizations to other spaces. We shall come across partially defined mappings. The notation φ : P → P ′ is used in order to point out t...

We construct a denotational model of linear logic, whose objects are all the locally convex and separated topological vector spaces endowed with their weak topology. The negation is interpreted as the dual, linear proofs are interpreted as continuous linear functions, and non-linear proofs as sequences of monomials. We do not complete our constructions by a double-orthogonality operation. This ...

We investigate the theories LA,LAP,∀LAP of linear algebra, which were originally defined to study the question of whether commutativity of matrix inverses has polysize Frege proofs. We give sentences separating quantified versions of these theories, and define a fragment ∃LA of ∀LAP in which we can interpret a weak theory V 1 of bounded arithmetic and carry out polynomial time reasoning about m...

A potential advantage of the “Möbius” scheme, or any other strongly coupled lattice, is that the normal-mode oscillations are damped at rates which depend on both the horizontal and vertical chromaticities. This opens up the possibility of maintaining adequate damping even for quite negative chromaticity in one plane, provided the other is appropriately increased to compensate. This “chromatici...

The role of zonal flows in the formation of the transport barrier in the helical plasmas is analyzed using the transport code. A set of one-dimensional transport equations is analyzed, including the effect of zonal flows. The turbulent transport coefficient is shown to be suppressed when the plasma state changes from the weak negative radial electric field to the strong positive one. This bifur...

Several formalisms for computing the collision broadening of weak iron lines are compared. These include approximations to Van der Waals broadening, empirical enhancement factors, the WIDTH6 approximation, and the Anstee & O’Mara calculations. Abundances are computed for a set of red Fe I lines using solar data, to illustrate the effects of selecting one or other damping formalism. The main poi...

Abstract For studying the evolution of transverse deflection an extensible beam derived from connection mechanics, we investigate initial boundary value problem nonlinear equation with linear strong damping term, weak and source term. The key idea our analysis is to describe invariant manifold via Nehari manifold. To establish results global well-posedness solution, consider at three different ...

Magnetic linear gear provides a new and unique opportunity for coupling mechanical impedances and optimizing vibration damping. In the present paper a new magneto-mechanical vibration damper (the so-called Z-damper) is described. Its expected theoretical dynamic behavior shows a particularly high damping capability, a low frequency, as well as an optimal behavior for high frequencies.

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...

The contribution of foundation damping to offshore wind turbines (OWTs) is not well known, though researchers have back-calculated foundation damping from “rotor-stop” tests after estimating aerodynamic, hydrodynamic, and structural damping with numerical models. Because design guidelines do not currently recommend methods for determining foundation damping, it is typically neglected. This pape...