LATEST PAPERS
Performance tests of paint coatings used for masking armaments and military equipment
Norbert Radek
Abstrakt
The paper presents an analysis of the operational properties of paint coatings for use in military technology in the field of masking. The assessment of the properties was performed on the basis of measurements of the surface geometric structure and adhesion using the peel method. The measurements of specular gloss, colour in the range of 400-700 nm and reflectance in the range of 350-1200 nm were made in relation to the requirements of the Polish Defence Standard NO-80-A200. Coating systems are characterised by their low roughness and good adhesion. Due to their operational properties, the developed coating systems can be used on armaments and military equipment.
The modelling of layered rocks using a numerical homogenisation technique and an artificial neural network
Aleksander Urbański, Szymon Ligęza, Piotr Przecherski
Abstrakt
A method of creating a constitutive model of layered rocks based on an artificial neural network (ANN) is reported in this work. The ANN gives an implicit constitutive function ∑n+1=F(∑n,ΔE ), relating the new state of homogenized stresses ∑n+1 with the old state ∑n and with the increment of homogenized strains ΔE. The first step is to repeatedly run a strain- controlled homogenisation on an uni-dimensional finite element model of a periodic cell with elastic-plastic models (Drucker-Prager) of the components. Paths are created in (∑, E) space, from which, a set of patterns is formed to train the ANN. A description of how to prepare this data and a discussion on ANN training issues are presented. Finally, the procedure based on trained ANN is put into a finite-element code (ZSoil.PC) as a user-delivered constitutive function. The approach is verified by comparing the results of the developed model basing on ANN with a direct (single-scale) analysis, which showed acceptable accuracy.
The market square in Katowice – a place which no longer exists – an evolution of the spatial structure
Karolina Ptasińska-Gucik
Abstrkat
This study attempts to explain why the space in the centre of Katowice is formally called “The Market Square” even though the square itself no longer exists. Some archival documents and existing studies are analysed. The evolution of the market square in Katowice is presented against the background of historical and economic transformations, putting an emphasis on depicting valuable and interesting architecture that was irretrievably lost and replaced with entirely new urban fabric. Moreover, the article aims to show that the region of Upper Silesia does not only constitute industrial plants but also, created by the mixture of cultures and nationalities, other types of architecture, that was irretrievably lost. It was found out that the market is not actually the main square.
