Problem-based learning (PBL) is an educational method which involves learning by solving real problems. However, applying a PBL approach to engineering subjects in some cases became a challenging issue. Thus, it is important to determine the best ways in which engineering students can learn physics more effectively and solve problems relevant to their daily lives. The main aim of this study was to compare the final assessment grades in a physics course for students in the engineering program using PBL and traditional learning (TL) methods. The advantages and disadvantages of PBL and TL methods from the practical experience of lecturers are also presented. The study presented data of 460 first-year engineering students taking the physics course at Kaunas University of Technology. The information presented in this study is based on the insights, observations, and individual experiences of the authors as teaching staff. The results indicated that the application of the PBL method allows for enhancement in the teamwork, presentation, and critical thinking skills in physics. However, the TL method promotes the individual learning skills and wider theoretical knowledge in physics of students and is more suitable when the exam only includes closed-ended questions.

As the industry develops and energy demand increases, wind turbines are increasingly being used to generate electricity, resulting in an increasing number of obsolete turbine blades that need to be properly recycled or used as a secondary raw material in other industries. The authors of this work propose an innovative technology not yet studied in the literature, where the wind turbine blades are mechanically shredded and micrometric fibers are formed from the obtained powder using plasma technologies. As shown by SEM and EDS studies, the powder is composed of irregularly shaped microgranules and the carbon content in the obtained fiber is lower by up to seven times compared with the original powder. Meanwhile, the chromatographic studies show that no hazardous to the environment gases are formed during the fiber production. It is worth mentioning that this fiber formation technology can be one of the additional methods for recycling wind turbine blades, and the obtained fiber can be used as a secondary raw material in the production of catalysts, construction materials, etc.

A gliding arc discharge (GAD) plasma device has been developed and tested. Possible applications areas for GAD plasma could be microalgae suspension treatments and the creation of plasma-activated water. To understand its behavior, the influence of the input power on the electrical characteristics of the generated GAD plasma was investigated using an oscilloscope. The waveforms of the voltage and current of GAD plasma are presented. The duration of the discharge time and the evolution of the arc during discharge were determined and investigated. It was revealed that the increase in the output voltage prolonged the duration of the arc discharge. The composition of the air plasma was investigated using a flame-emission spectrometer and acousto-optic emission spectrometer. It was revealed that the main species in the emission spectra of the GAD air plasma were N₂, N₂⁺, N⁺, NO, and O species. Furthermore, the increase in the input power enhanced the ionization degree of the air plasma and increased the intensities of the emission lines associated with N₂⁺, NO, and O species. An increase in the conductivity of the BG-11 medium was observed. Physicochemical analyses of the plasma-activated BG-11 medium indicated an increase in the concentration of nitrite and nitrate ions and hydrogen peroxide with an enhancement of the voltage.