Using string-matching to analyze hypertext navigation

A method of using string-matching to analyze hypertext navigation was developed, and evaluated using two weeks of website logfile data. The method is divided into phases that use: (i) exact string-matching to calculate subsequences of links that were repeated in different navigation sessions (common trails through the website), and then (ii) inexact matching to find other similar sessions (a community of users with a similar interest). The evaluation showed how subsequences could be used to understand the information pathways users chose to follow within a website, and that exact and inexact matching provided complementary ways of identifying information that may have been of interest to a whole community of users, but which was only found by a minority. This illustrates how string-matching could be used to improve the structure of hypertext collections

Investigations on finite ideal quantum gases

Recursion formulae of the N-particle partition function, the occupation numbers and its fluctuations are given using the single-particle partition function. Exact results are presented for fermions and bosons in a common one-dimensional harmonic oscillator potential, for the three-dimensional harmonic oscillator approximations are tested. Applications to excited nuclei and Bose-Einstein condensation are discussed.Comment: 13 pages, 7 postscript figures, uses 'epsfig.sty'. Submitted to Physica A. More information available at http://obelix.physik.uni-osnabrueck.de/~schnack

Mathematical models of 2D plotter components

This paper deals with most common 2D plotter components and provide identification procedure and exact parameters needed for mathematical modelling. Since a lot of Open-Source CNC machines use the same components, this information can be used to build-upon and improve performance of millions of machines.Tato práce se zabývá postupem identifikace a získáním přesných paramterů nejběžnějších součástí 2D polohovacího plotru, které jsou potřebné pro matematické modelování. Jelikož značná část Open-Source CNC strojů využívá totožné komponenty, může být tato informace využita k vylepšení vlastností miliónů strojů