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As a result of the increase in energy demand and government subsidies, the usage of wind turbine system (WTS) has increased dramatically. Due to the higher energy production of a variable-speed WTS as compared to a fixed-speed WTS, the demand for this type of WTS has increased. In this study, a new method for the calculation of the power output of variable-speed WTSs is proposed. The proposed model is developed from the S-type curve used for population growth, and is only a function of the rated power and rated (nominal) wind speed. It has the advantage of enabling the user to calculate power output without using the rotor power coefficient. Additionally, by using the developed model, a mathematical method to calculate the value of rated wind speed in terms of turbine capacity factor and the scale parameter of the Weibull distribution for a given wind site is also proposed. Design optimization studies are performed by using the particle swarm optimization (PSO) and artificial bee colony (ABC) algorithms, which are applied into this type of problem for the first time. Different sites such as Northern and Mediterranean sites of Europe have been studied. Analyses for various parameters are also presented in order to evaluate the effect of rated wind speed on the design parameters and produced energy cost. Results show that proposed models are reliable and very useful for modeling and optimization of WTSs design by taking into account the wind potential of the region. Results also show that the PSO algorithm has better performance than the ABC algorithm for this type of problem.

WOS: 000336183300022 ; As a result of the increase in energy demand and government subsidies, the usage of wind turbine system (WTS) has increased dramatically. Due to the higher energy production of a variable-speed WTS as compared to a fixed-speed WTS, the demand for this type of WTS has increased. In this study, a new method for the calculation of the power output of variable-speed WTSs is proposed. The proposed model is developed from the S-type curve used for population growth, and is only a function of the rated power and rated (nominal) wind speed. It has the advantage of enabling the user to calculate power output without using the rotor power coefficient. Additionally, by using the developed model, a mathematical method to calculate the value of rated wind speed in terms of turbine capacity factor and the scale parameter of the Weibull distribution for a given wind site is also proposed. Design optimization studies are performed by using the particle swarm optimization (PSO) and artificial bee colony (ABC) algorithms, which are applied into this type of problem for the first time. Different sites such as Northern and Mediterranean sites of Europe have been studied. Analyses for various parameters are also presented in order to evaluate the effect of rated wind speed on the design parameters and produced energy cost. Results show that proposed models are reliable and very useful for modeling and optimization of WTSs design by taking into account the wind potential of the region. Results also show that the PSO algorithm has better performance than the ABC algorithm for this type of problem.

Food production systems are undergoing a structural transformation towards a sustainable resilient state, offering opportunities for economic benefits, employment creation, and enhanced food safety and security. Governing this sustainability transition is a complex process which calls for interventions at all policy levels, including higher education. Adopting an agri-food systems perspective, the Western Balkans countries are facing challenges which are mostly related to issues such as the modernization of food engineering and food management practices, the organic agriculture production, the post-harvest processes, the supply chain management, the corresponding environmental footprint, etc. Tackling with the afore-mentioned topics requires educational interventions (among other actions), which may contribute effectively towards the specific sustainability transition. To this purpose, and in light of these countries' current convergence, with the European Union, the Erasmus+ "STEPS" project offered a unique opportunity for collaboration between eleven (11) European partners, who led to the development of a joint Master of Sciences Program entitled "Sustainable Food Production Systems" with two directions: "Food Engineering and Food Safety", and "Food Production Systems Management". The paper sheds light on the development process of the curriculum, providing evidence on the design process, the structure and the syllabus of the courses, the necessary accreditation process, and the benefits of the new joint postgraduate program.