Modern cities are increasingly promoting their own individual brands to gain a competitive advantage. 28 Polish cities, after joining the Cittaslow international network of cities, can additionally use their native brand in their activities. The aim of the author was to answer the question: should cities only use an individual brand, or maybe they can support these activities with a common brand strategy. The growth of interest in individual brands of 28 cities belonging to the Cittaslow network has been evaluated, also their popularity, popularity of the native brand on the Facebook, and the use of the Cittaslow brand by cities on their websites were analysed. It was noticed that not all cities use the Cittaslow logo. But most cities in Cittaslow publish a link to the network and brand information on their websites. The native brand Cittaslow is in Poland at the positioning stage but probably its popularity will grow as the benefits from using it begin to be noticed.
Heat transfer is an irreversible process. This article defines the entropy increment as a measure of energy degradation in heat transfer realized in typical surface heat exchangers. As an example of the proposed entropy increase method, presented below are the calculations for heat exchangers working in a typical Clausius-Rankine cycle. The entropy increase in such exchangers inevitably leads to increased fuel consumption and, as a further consequence, to increased carbon dioxide emission.