In its history, Poland was usually more oriented to land than to the sea. For many centuries we have not been able to see the opportunities and potential created by the coastal location of our country. In the current strategic documents in Poland, there are also no proper references to the maritime security of the state, although we are a member of both NATO and the European Union. The article presents the creation process in 2015–2017 and the content of a unique document devoted to this issue: Poland’s Strategic Concept for Maritime Security, which was born thanks to the efforts of “enthusiasts” of maritime affairs from the Naval Academy, Shipbuilding Council and the Institute of General Józef Haller under the leadership of the National Security Bureau. In the authors opinion, the document is to form the basis for work on the future maritime security strategy of our country, and also become the “engine” of public discussion in Poland on maritime security issues and the effective use of the coastal position of the state for economic development.

The purpose of the chapter is to verify the hypothesis that Świętokrzyskie Region can build its regional brand and competitive advantage based on the geotourism product. The following research questions were set: how the geological resources have been used to tourism product, has the brand sufficient product which supports the expected identity, is the tourism infrastructure coherent with core of the product. Content analysis (scientific literature, planning documents, websites, guide books) and observations during the field visits (11 days) have been used as research method. The above hypothesis has been fully confirmed; resources and interpretation infrastructure are strong enough to recognize that regional geotourism product already exists. More, it is unique on a national scale and therefore has competitive advantage. It is sufficient base to build its brand; first addressed to special interests tourists, second to attract general oriented clients but it will need considering to include industrial tourism components.

The paper presents an overview of linearization methods of the non-linear state equation. The linearization is developed from the

point of view of the application in the theoretical electrotechnics. Some aspects of these considerations can be used in the control theory. In particular the main emphasis is laid on three methods of linearization, i.e.: Taylor’s series expansion, optimal linearization method and global linearization method. The theoretical investigations are illustrated using the non-linear circuit composed of a solar generator and a DC motor. Finally, the global linearization method is presented using several examples, i.e. the asynchronous slip-ring motor and non-linear diode. Furthermore the principal theorem concerning the BIBS stability (bounded-input bounded state) is introduced.

This work presents a comparative analysis of the phenolic composition (UHPLC-PDA-ESI-MS3, HPLC-PDAfingerprint, UV-spectrophotometric methods) and antioxidant activity (DPPH, FRAP) of leaf samples from two vegetation seasons of a medicinal and dietary plant Sorbus domestica growing in its natural habitat (Croatia, C) and cultivated in Poland (P). The samples from both sources were rich in structurally diverse polyphenols (44 analytes; P: 73.4–76.6 and C: 98.3–106.7 mg GAE/g dry leaves) including the dominating flavan-3-ols and flavonoids. The greatest qualitative and quantitative differences were observed for flavonoids (P: 14.3–20.3%; C: 27.5–34.1% of polyphenols) – in the Polish samples flavonoid diglycosides predominated, in the Croatian samples the contents of both monoglycosides and diglycosides were similar. In the case of dry methanolic extracts, despite the higher extraction efficiency obtained for the Croatian samples (32–36% vs 23–24%), the quality of the extracts was comparable, both in terms of the total phenolic content (P: 269.4–280.0; C: 297.6–304.4; mg GAE/g dry extract) and antioxidant activity parameters (DPPH, EC50, μg/mL. P: 10.5–10.9, C: 10.0–10.3; and FRAP, mmol Fe2+/g, P: 6.64–7.13, C: 7.06–7.11). As a result, the study confirmed the influence of environmental conditions on the phenolic profile and antioxidant capacity of S. domestica leaves, as well as showed that despite some differences, plant materials from both Poland and Croatia might be suitable for production of natural health products.