The subject of this paper is the so-called open innovation model and its importance for the development of small and medium-sized enterprises (in further paper SMEs). The importance of the open innovation model for the development of SMEs, as well as identifying the major obstacles that stand in the way of wider application of this model in SMEs, is the aim of this research. The study used a variety of methods, such as induction and deduction, analysis and synthesis, as well as the method of description. SMEs are the driving force of economic development of the state, since they employ the largest part of the working-age population, significantly influence the formation of gross domestic product, solve the unemployment problem, raise the standard of living and strengthen the country's international competitive position through export business. By facilitating the process of intensive exchange of knowledge, tools and technology among certain economic actors, the concept of open innovation has contributed to improving the innovation of the SMEs sector as a key driver of the growth of their competitiveness in the knowledge economy. Innovation is a powerful tool for new SMEs to successfully enter the market and change the existing situation, enabling existing companies to maintain or improve their position on the market by improving their innovation.

The purpose of the research of this paper is to conduct an analysis of the impact of corporate entrepreneurship on the business performance of a modern enterprise in the conditions of global competition. The research goal is to show through the comprehensive approach the significance of this interdependence, further expand the existing knowledge base and suggest to organizations to turn to this entrepreneurial model in order to achieve a higher degree of flexibility and innovation. Scientific methods of induction, deduction, comparison, analysis, and synthesis used in the research unambiguously indicate that the application of corporate entrepreneurship simultaneously contributes to the improvement of the business results of both individuals within the organization and the organization themselves, leading ultimately to a better market positioning of enterprises. Corporate entrepreneurship encourages employees to take an individual initiative , thus creating a perfect ground for doing new innovations that are the only guarantee of survival in a dynamic market XXI century.

The aim of this paper is to review the current international competitiveness of the Republic of Serbia, as well as the conditions and indicators of business in the Republic of Serbia, in order to determine progress compared to the previous period, discover obstacles and present ways to overcome them. The paper is based on the fact that Serbia's competitiveness, although it has been increasing in recent years, is still relatively low as a result of a number of gaps and that, among other things, it is necessary to increase the inflow of FDI, which in the past was significant for GDP growth, as the competitiveness of the economy of the Republic of Serbia would increase.

Zaptivenost kanalskih mreža predstavlja važan element vazdušnih sistema KGH i objekata u celini. Zaptivenost se veoma retko testira u ovom regionu i to uglavnom visokopritisnih sistema. Postoji više zemalja koje propisima regulišu ovu problematiku, ali se svi oni baziraju na smernicama Euroventa 2–2. U radu se analiziraju potreba i način testiranja prema pomenutim smernicama. Takođe, date su i preporuke za primenu drugih propisa koje dopunjuju pomenute smernice. Imajući u vidu značaj sistema KGH, preporučuje se testiranje i niskopritisnih kanalskih mreža na zaptivenost.