Gallery — Math

Wiskundecollega Pedro Tytgat ontdekte onlangs een merkwaardige applet op het internet. Op http://functionspace.org/topic/1638/opinion/7591 vond hij tussen een hele serie animated gifs een applet voor de krimpende puntenketting die meetkundig gezien niet veel meer doet dan het berekenen van het midden van een lijnstuk. Deze applet viel niet alleen op door haar meetkundige schoonheid maar ook door een korte discussie over een mogelijke verklaring via dominante eigenwaarden en eigenvectoren.De aangekondigde verklaring ontbrak echter op deze site. Korte tijd na de ontdekking van de stelling van de krimpende puntenketting kwam er een compacte maar geïnspireerde analyse van Dirk Danckaert. In dit verslag probeer ik zijn ideën iets breedvoeriger uit te schrijven.

ALGEBRA

Les classes smfbook et smfart sont destinées à la composition en LaTeX des monographies et articles édités par la Société Mathématique de France.

The classes smfbook and smfart are intended to help the preparation in LaTeX of the monographs and articles to be published by the French Mathematical Society.

Ovde je samo postavka pitanja koja sam prikupio po raznim rokovima. Ako naðete da se neka pitanja ponavljaju ili da rešenje nekih pitanja nije tačno, javite mi.

The aim of this laboratory work is to design a strut/bracket assembly for aircrafts. Experiments are carried out to determine mechanical properties of certain materials.The material chosen is Mild Steel. Given the possible condition experienced by the material and the safety factor, the dimensions for the designs of the strut/bracket assembly for aircrafts are obtained to avoid failure by yield or fracture. The diameter of the pin, d ,which is subjected to shear stress should be larger than 14.56mm. The diameter of the rod, D, should be larger than 12.74mm. The thickness of the rod would be 10mm.

Cette courte note décrit la classe LaTeX jsfds et illustre son usage en se présentant sous la forme d'un article du Journal de la Société Française de Statistique. Cette classe est une adaptation de la classe publique \texttt{imsart}.

TP thermodynamique

Principal Components Analysis (PCA) and Canonical Correlation Analysis (CCA) are among the methods used in Multivariate Data Analysis. PCA is concerned with explaining the variance-covariance structure of a set of variables through a few linear combinations of these variables. Its general objectives are data reduction and interpretation. CCA seeks to identify and quantify the associations between two sets of variables i.e Pulp fibres and Paper variables.PCA shows that the first PC already exceeds 90% of the total variability. According to the proportion of variability explained by each canonical variable , the results suggest that the first two canonical correlations seem to be sufficient to explain the structure between Pulp and Paper characteristics with 98.86%. Despite the fact that the first the two canonical variables keep 98% of common variability, 78% was kept in the pulp fiber set and about 94% of the paper set as a whole. In the proportion of opposite canonical variable,there were approximately 64% for the paper set of variables and 78% for the pulp fiber set of variables kept for the two respectively.