SCIDAR - A Digital Archive of the University of Kragujevac

The Kraus form of the completely positive dynamical maps is appealing from the mathematical and the point of the diverse applications of the open quantum systems theory. The “integral”, i.e. so-called, Kraus form [1] of a com pletely positive dynamical map for an open quantum sys tem [2, 3] is appealing for the mathematical reasons. Mathematical existence of the Kraus form for such pro cesses is guaranteed by the Kraus theorem, universally [1-3]. On the other hand, a Kraus-form (KF) may be re...

The aim of this paper is to combine distance functions and Boolean propositions by developing a formalism suitable for speaking about distances between Boolean formulas. We introduce and investigate a formal language that is an extension of classical propositional language obtained by adding new binary (modal-like) operators of the form $D_{leqslant s} $ and $D_{geqslant s}$, $sinmathds{Q}_0^+$. Our language all-ows making formulas such as $D_{leqslant s}(alpha,beta)$ with the intended meanin...

Proper functioning of the suspension of the railway vehicles is of great importance for the normal functioning of railway traffic. The coil springs are a very common element of the railway vehicles suspension. They are obtained by winding cold drawn wire along the line of the coil with equal distances between the threads. Thanks to these distances, the height of the spring changes easily under the load. Cold drawing is the process of kneading the surface layer of the wire by passing it throug...

This paper presents one universal method for determination of optimal locations of strain gauges on instrumented wheelsets for measurement of wheel-rail contact forces and contact point position. The method is based on development of wheel model and systematically analysis of results of FEM calculation. The procedure is shown on standard 22.5 t wheelset for freight wagons. For analysed wheel, 4 optimal radial distances for measurement of 3 parameters (vertical force Q, lateral force Y and loc...