Differential Speed Rolling: A New Method for a Fabrication of Metallic Sheets with Enhanced Mechanical Properties

This chapter presents an actual progress in the usage of a new processing method called differential speed rolling (DSR) to a fabrication of metallic sheet materials with enhanced mechanical properties. An introduction of the rolls speed differentiation to a rolling process results with qualitative and quantitative changes of imposed strain and thus to new structural effects as compared to a conventional rolling. The presence of additional high through-thickness shear strain in the DSR technique is utilized to a substantial grain refinement (to a fabrication of high-strength ultrafine-grained materials) and therefore is regarded as one of the severe plastic deformation (SPD) methods. In this chapter, mechanical properties of selected DSRed metals are compared to those of their counterparts processed by competitive hydrostatic SPD methods. Moreover, the imposed complex strain state in the DSR method significantly affects a crystallographic texture of fabricated sheet materials leading to more favorable anisotropic characteristics and to an improved formability that is especially important in the case of aluminum and magnesium alloys

Die mittel- und osteuropäischen Länder auf dem Weg in die EU

Bereits ab dem Jahr 2003 plant die EU im Rahmen der Osterweiterung die ersten Beitrittskandidaten aufzunehmen. Nach welchen ökonomischen Kriterien entscheidet die EU über die Beitrittsfähigkeit? Wie weit sind die Kandidaten aus Mittel- und Osteuropa auf dem Weg in die EU vorangekommen? --

Russland: verheerende Bilanz

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Mereology and uncertainty

Mereology as an art of composing complex concepts out of simpler parts is suited well to the task of reasoning under uncertainty: whereas it is most often difficult to ascertain whether a given thing is an element of a concept, it is possible to decide with belief degree close to certainty that the class of things is an ingredient of an other class, which is sufficient for carrying out the reasoning whose conclusions are taken as true under given conditions. We present in this work a scheme for reasoning based on mereology in which mereology in the classical sense is fuzzified in analogy to the concept fuzzification in the sense of L. A. Zadeh. In this process, mereology becomes rough mereology

Die neuen EU-Mitgliedsländer und EU-Anwärter

Mit der 2004 eingeleiteten fünften und größten Erweiterung der Europäischen Union ist die Zahl der Mitgliedstaaten auf 25 gestiegen. Diese Erweiterungsrunde wird mit dem bevorstehenden Beitritt Bulgariens und Rumäniens abgeschlossen. Wie ist die Aufnahme der mittel- und osteuropäischen Länder in die EU zu beurteilen? --