The petrographic composition of coal has a significant impact on its technological and sorption properties. That composition is most frequently determined by means of microscope quantitative analyses. Thus, aside from the purely scientific aspect, such measurements have an important practical application in the industrial usage of coal, as well as in issues related to the safety in underground mining facilities. The article discusses research aiming at analyzing the usefulness of selected parameters of a digital image description in the process of automatic identification of macerals of the inertinite group using neural networks. The description of the investigated images was based on statistical parameters determined on the basis of a histogram and co-occurrence matrix (Haralick parameters). Each of the studied macerals was described by means of a 20-element feature vector. An analysis of its principal components (PCA) was conducted, along with establishing the relationship between the number of the applied components and the effectiveness of the MLP network. Based on that, the optimum number of input variables for the investigated classification task was chosen, which resulted in reduction of the size of the network’s hidden layer. As part of the discussed research, the authors also analyzed the process of classification of macerals of the inertinite group using an algorithm based on a group of MLP networks, where each network possessed one output. As a result, average recognition effectiveness of 80.9% was obtained for a single MLP network, and of 93.6% for a group of neural networks. The obtained results indicate that it is possible to use the proposed methodology as a tool supporting microscopic analyses of coal.
The development of both the town and the administrative commune of Zielona Góra is characterised by a progressive process of uncontrolled linear urban development, so called urban sprawl. This phenomenon has existed in the town for a long time, but because of the fast development in the 21st century it is now even stronger and has an unfavourable impact on the dwellers’ comfort, communication and accessibility. The directions of changes adopted for spatial development in the current strategic documents of the new town (since 1 January 2015), which came into being as a result of the merger between the town and the rural commune of Zielona Góra, do not guarantee that the unfavourable processes will be stopped. The process of uncontrolled urban development results in the growth of dense urban structures along the roads and communication routes. This prevents an optimum use of areas located further away or behind the existing infrastructure and causes dead zones to appear, where there are no communications or infrastructure. With each new investment (a plot of land with access to a public road, as specified by the regulations) the distance between recreational areas (green spaces) and the town centre increases. The deteriorating dwelling conditions are a direct result of the unfavourable phenomenon of urban sprawl.