http://dspace.beu.edu.tr:8080/xmlui/handle/123456789/16704 2026-04-23T06:46:00Z http://dspace.beu.edu.tr:8080/xmlui/handle/123456789/16720 THE OPTOELECTRONIC CHARACTERIZATION OF Ag DOPED ZnO THIN FILMS RUZGAR, Serif This study investigates the properties of silver (Ag)-doped zinc oxide (ZnO) thin films, which possess significant potential for various optoelectronic applications. The films were fabricated utilizing a cost-effective nebulizer spray technique. Structural analysis confirmed that both the undoped and Ag-doped samples crystallized in the hexagonal wurtzite phase, characteristic of ZnO. Scanning electron microscopy (SEM) revealed that the incorporation of Ag significantly altered the surface morphology, resulting in an increased grain size and the formation of more irregular surface features. Optical measurements demonstrated that while Ag doping slightly reduced the films' transmittance, it concurrently narrowed the optical band gap, thereby enhancing light absorption within the visible region. Moreover, the photoluminescence characteristics were observed to be strongly dependent on the presence of the silver dopant. Finally, current-voltage (I-V) characterization affirmed that the Ag-doped ZnO films exhibited superior photoconductivity compared to their undoped counterparts. An evaluation of the photodetector performance parameters indicated a substantial improvement in photosensitivity, which increased from a value of 14.7 in undoped ZnO to 64.2 following the incorporation of Ag. 2026-01-01T00:00:00Z http://dspace.beu.edu.tr:8080/xmlui/handle/123456789/16719 FLOATING PV DISTRIBUTED GENERATION SYSTEM PROPOSAL AND OPTIMAL LCL FILTER DESIGN FOR AKKÖPRÜ DAM, MUĞLA, TURKEY KARADENİZ, Alp The study investigates the burgeoning potential of floating photovoltaic (FPV) panels and proposes their installation in Akköprü Dam, Muğla, Turkey. Also, different kinds of power electronics-based converters and inverters are used in the grid integration of FPV. These electrical gadgets cause harmonics in voltage and current waveforms to be introduced into the grid. Therefore, a 2 MW FPV system is designed to be combined and connected to the 120 kV common grid by a 25 kV distribution feeder. This research examines optimal passive filter designs and harmonic analysis for FPV power systems. Also, utilising real-world meteorological data that is taken from Dalaman, Muğla, Turkey, such as solar irradiation, as an input parameter of the FPV. After that, to study harmonic analysis and optimal filter design, a mathematical strategy is proposed. Moreover, the arithmetic mean (AM) of real data is considered the input value of FPV. Also, to discover the best filter solution, the Antlion Optimisation (AOA) algorithm is used. According to IEEE 519 standards, the optimisation method seeks to minimise both the voltage levels in p.u. and the total harmonic distortion (THD) of current and voltage values. Moreover, the FPV model is simulated with optimal LCL filters by using daily data (DD) solar irradiation values. Finally, the performance analysis based on the results of AM data and DD is studied. Lastly, the results are comparatively discussed. 2026-01-01T00:00:00Z http://dspace.beu.edu.tr:8080/xmlui/handle/123456789/16718 EVALUATION OF TEMPERATURE-DEPENDENT VISCOUS DAMPING PERFORMANCE IN A SMART FLUIDIC VIBRATION ISOLATION SYSTEM SAHIN, Burhan; GORGULU, Yasin Furkan This study investigates the thermofluidic and structural behavior of a multichamber fluidic vibration damping mechanism designed for aerospace applications. A computational fluid dynamics approach, coupled with structural finite element analysis, is employed to evaluate the interaction between pressuredriven flows and material deformation. Four working fluids—Air, Argon, Carbon Dioxide, and Helium—were individually analyzed under a uniform inlet gauge pressure of 200 MPa. The results indicated peak flow velocities exceeding 560 m.s-1, localized pressure maxima of 1.01 MPa, and turbulence kinetic energy values surpassing 197,000 m².s-², reflecting high internal mixing and energy dissipation. Thermal analysis under convective boundary conditions (15 W.m-2·K-1, 280 K ambient) yielded a maximum fluid temperature of 299.7 K. Subsequent structural analyses mapped computational fluid dynamics-derived pressure loads onto three engineering materials: AL 6061-T6, Titanium Ti-6Al-4V, and AISI 316L stainless steel. Although stress levels remained comparable (~3638 MPa), maximum deformation varied significantly: 0.0102 mm for AL 6061T6, 0.0065 mm for Ti-6Al-4V, and 0.0043 mm for 316L steel. These findings underscore the critical role of fluid selection and material choice in vibration isolation performance. The integrated fluid-structure interaction simulation framework provides valuable insights for the design and optimization of advanced damping systems in aerospace and energy applications. 2026-01-01T00:00:00Z http://dspace.beu.edu.tr:8080/xmlui/handle/123456789/16717 A PROTOTYPE FOR A CONTINUOUS NANOFIBER PRODUCTION METHOD ERKUT, Güray; ŞENER, Ercan; VATANSEVER BAYRAMOL, Derman This study aimed to develop a prototype for a new method of continuous nanoscale fiber production without using high-voltage. Two concentrations of alginate (1% and 2%) polymer solutions were prepared and used to fabricate nanofibers in order to test and analyze the performance of the prototype that was designed and built in this study. The production of the fibers was initially tested by obtaining optical microscope images. Scanning electron microscopy (SEM) was used to analyze both the surface morphology and diameter of the selected finest continuous fibers. The SEM images and diameter measurement results confirmed that continuous nanofibers was successfully produced with the prototype developed in this study. 2026-01-01T00:00:00Z