Sökresultat

Filtyp

Din sökning på "*" gav 529352 sökträffar

Sustainable Bioenergy Systems: Experiences from Sweden

Many aspects of present energy systems and the direction towards future energy systems are incompatible with sustainable development. Sustainable bioenergy systems contribute to combating climate change and improving energy security. Expanding bioenergy decreases carbon dioxide emissions if replacing fossil fuels, establishing energy crops, or integrating with carbon capture and storage, and incre

Simulation of drying stresses in Wood. Part I: comparison between one- and two-dimensional models

A number of rheological models of drying wood have been presented during the last ten years. At the material point level, most models show high accuracy. The models in themselves, however, have no value unless used for improving wood drying, technique, quality, etc. To achieve this, they have to be implemented in applicable programs/ methods. In this article, the implementation of a material model

A DAE approach for solving the elasto-plastic boundary value problem

In this study an alternative integration scheme for elasto-plasticity based on a Diagonal Implicit Runge-Kutta (DIRK) scheme originally proposed by Ellsiepen (1999) is investigated. In contrast to clasical approaches, the DIRK scheme is applied to the balance of momentum as well as the constitutive evolution equations. The presented numerical algorithm is applied to an elastoplastic bounadry value

Another look at weak feedback polynomials in the nonlinear combiner

Feedback polynomials with low degree multiples of low weight should be avoided in linear feedback shift registers when used in nonlinear combiners. We consider another class of weak feedback polynomials, namely the class when taps are located in small groups. This class was introduced in 2004 demonstrating that the resulting distinguishing attack can sometimes be better than the one using low weig

Radiation efficiency and surface waves for patch antennas on inhomogeneous substrat

In this paper the surface wave characteristics, as well as the radiation efficiency and the directivity of a patch antenna, with a given current distribution, located on top of an inhomogeneous, isotropic substrate are calculated. The substrate is infinite in the lateral directions and inhomogeneous with respect to the height coordinate. The surface waves in the substrate are analyzed using the pro