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Conference Object COMPARISON OF COMPUTER-BASED PROPAGATION MODELS WITH EXPERIMENTAL DATA COLLECTED IN AN URBAN AREA AT 1800 MHz(Ieee, 2015) Acar, Tarik; Caliskan, Fatma; Aydin, ElifNowadays a lot of models are set for the efficient and economic usage of frequency band since the band is a limited source. Therefore, the propagation models created for this purpose were studied in the literature. These models are Free Space Path Loss (Fspl) + Reflection plus Multiple Diffraction (RMD), COST-Hata and COST-WI models. In order to compare the success of the models, electric field strength measurements were taken in a chosen district (Mustafa Kemal Mahallesi Ankara, Turkey) where an irregular structure style can be observed. First set of measurements were recorded at random coordinates and second set of measurements were collected by the following coordinates tracking on a single line. As a conclusion, measured values were compared with the results which were taken from the mentioned models with graphical presentations. The most appropriate model was tried to be found and as another aim of the study, a correction factor was generated as a modification for COST-Hata propagation model.Article Citation - WoS: 56Best Proximity Point on Different Type Contractions(Natural Sciences Publishing Corp-nsp, 2011) Karapinar, Erdal; Erhan, Inci M.In this manuscript, some proximity points are obtained by using different types cyclic contractions. Also, generalized cyclic Meir Keeler contraction is introduced and a new fixed point theorem for this cyclic mapping is stated.Conference Object Citation - Scopus: 1A New E-Commerce Model Suggestion of Agricultural Products(Springer international Publishing Ag, 2024) Eryilmaz, Meltem; Briman, Mohammed Khalid Hilmi; Yakut, GokceThis study aims to create an e-commerce application that enables farmers to sell their products directly to their customers without resorting to intermediaries by a smart cargo box. It presents a method by which the agricultural industry can gain momentum in e-commerce. The main contributions of the study are an e-commerce application that enables farmers to sell their products directly to the customer without the need for an intermediary and the design and implementation of a smart cargo box that is tailored to carry agricultural items throughout the delivery process that locks and unlocks only via QR code generated by the application after order. Django FrameworkNext.js, React.js, and Redux are used for the system development. The database is created with PostgreSQL using migrations, and AmazonWeb Services is used for this database. The "ESP32 Cam" is used to read the QR Code.Conference Object Infrared Absorption Spectroscopy of Monolayers with Thin Film Interference Coatings(Ieee, 2017) Ayas, Sencer; Bakan, Gokhan; Ozgur, Erol; Celebi, Kemal; dana, AykutluWe report high performance Infrared spectroscopy platforms based on interference coatings on metal using CaF2 dielectric films and Ge2Sb2Te5 (GST) phase-change films. IR vibrational bands of proteins and organic monolayers are also detected.Article Comparative Analysis of Vibration Axis Effects on Ultrasonic Vibration-Assisted Machining of Inconel 718(Multidisciplinary Digital Publishing Institute (MDPI), 2026) Namlu, R.H.; Kilic, Z.M.Inconel 718 is widely utilized in critical engineering sectors, particularly aerospace, owing to its exceptional creep resistance, corrosion resistance, and retention of mechanical strength at elevated temperatures. However, its high hardness, low thermal conductivity, and strong work-hardening tendency make it extremely difficult to machine using conventional techniques. Ultrasonic Vibration-Assisted Machining (UVAM) has emerged as an effective strategy to overcome these limitations by superimposing high-frequency, low-amplitude vibrations onto the cutting process. Depending on the vibration direction, UVAM can significantly change chip formation, tool–workpiece interaction, and surface integrity. In this study, the influence of three UVAM modes—longitudinal (Z-UVAM), feed-directional (X-UVAM), and multi-axial (XZ-UVAM)—on the machining behavior of Inconel 718 was systematically investigated. The findings reveal that XZ-UVAM provides the most advantageous outcomes, primarily due to its intermittent cutting mechanism. Compared with Conventional Machining (CM), XZ-UVAM reduced cutting forces by up to 43% and areal surface roughness by 37%, while generating surfaces with more uniform topographies and smaller peak-to-valley variations. Furthermore, UVAM enhanced subsurface microhardness as a result of the surface hammering effect, which may improve fatigue performance. XZ-UVAM also effectively minimized burr formation, demonstrating its potential for high-quality, sustainable, and efficient machining of Inconel 718. © 2026 by the authors.Conference Object Model Enhancement for UAV Stealth in X-Band(IEEE, 2025) Unalir, Dizdar; Yalcinkaya, Bengisu; Aydin, ElifWith the rapid advancement of technology, radar detection techniques continue to evolve, challenging the effectiveness of traditional unmanned aerial vehicles (UAVs) stealth techniques. As the usage of UAVs in military applications expands, the need for effective radar cross section reduction (RCSR) methods to enhance their stealth capabilities has grown significantly. In this study, we propose an enhancement of a previously developed Low-RCS UAV model, focusing on RCSR with shaping technique in the X-band. For the identification and optimization of the UAV model's highly reflective components, a detailed simulative analysis of the RCS was performed using CST Studio Suite Environment. The modifications are applied to the body and leg components to minimize radar reflections. Simulation results demonstrated that the proposed enhancements significantly reduced RCS values compared to the original Low-RCS UAV model. A total of 13 dBsm reduction in RCS was observed compared to the traditional UAV models. Comparative analysis for different frequencies in X-Band and various aspect angles confirmed the effectiveness of the improved design, validating its potential for stealth applications. The findings can contribute to the research in UAV stealth technology and provide insights into future low-visibility UAV designs.Conference Object A remote laboratory for training in radio communications(Ieee, 2007) Kara, Ali; Aydin, Elif Uray; Oektem, Rusen; Cagiltay, NergizThis paper presents, first, a short survey of remote laboratory initiatives in electrical and computer engineering, and then discusses design and development phases of remote laboratory environment on radio communications, the ERRL (European Remote Radio Laboratory). As being the first. attempt in establishing of such a large scale remote laboratory on radio communications, ERRL enables access to high technology RF equipments and setups through the Internet. The software structure, target groups and experimental set ups of ERRL are shortly discussed. First attempts on implementation of pilot experiments are discussed.Conference Object Citation - Scopus: 2A New Approach for Addressing Slip Ratio Optimization and Trajectory Tracking Challenges in Autonomous Tractor Operations(Ieee, 2024) Aydin, Gulsah Demirhan; Aydemir, Ali Bahadir; Kansou, Mohamad Thaer; Altinuc, Kemal Orcun; Mechatronics Engineering; Mechatronics EngineeringThe usage of autonomous agricultural machines is increasing. In this study, two controllers have been designed for trajectory following and longitudinal tire slip ratio control of a rear-wheel independent traction electric autonomous tractor. The first controller is model predictive control (MPC) and the second controller is proportional integral derivative (PID) based. To evaluate the performance of the controllers in the simulation environment, a mathematical tractor model is prepared. Simulations have been made and performances of the designed controllers are shared.Conference Object Citation - WoS: 1Parking Space Occupancy Detection Using Deep Learning Methods(Ieee, 2018) Akinci, Fatih Can; Karakaya, MuratThis paper presents an approach for gathering information about the availabilty of the parking lots using Convoltional Neural Network (CNN) for image processing running on an embedded system. By using an efiicent neural network model, we made it possible to use a very low cost embedded system compared to the ones used in previous works on this topic. This efficient model's performance is compared to one of the models that proved its accuracy in image classification competitions. In these tests, we used datasets that has thousands of different images taken from parking lots in different light and weather conditions.Article Synthesis, Photophysical Properties, and Photodynamic Therapy Efficacies of Meso-Pyridine Bodipys and Their Ruthenium Complexes(Wiley, 2025) Aksoy, Burcu Topaloglu; Ozcan, Emrah; Bulut, Onur; Kazan, Hasan Huseyin; Cosut, BunyeminPhotodynamic therapy (PDT) is a candidate approach for cancer treatment. In PDT applications, a fluorescent molecule, called photosensitizer (PS), induces light-directed production of reactive species, resulting in cytotoxicity. Having tunable fluorescence and easy derivatization properties, the BODIPY core is widely used as a PS. To further increase the light-induced toxicity, studies have shown the conjugation of heavy metals to the BODIPY core. However, such complexes are still needed to fully figure out their potential. In the current study, as part of an ongoing one, two novel ruthenium-BODIPY complexes were synthesized and characterized by structural, photophysical, and biological methods. To obtain complex structures between ruthenium dimers and BODIPY units, [RuCl2(p-cymene)](2) dimers, and non-iodo and di-iodo BODIPY derivatives were reacted in methanol-tetrahydrofuran (THF) medium. Photophysical properties, fluorescence lifetime, molar extinction coefficient, photostability, and capability of singlet oxygen generation were determined using absorption and/or fluorescence spectroscopy. Besides, the structures of the complexes were further clarified by the single-crystal X-ray technique. The cytotoxicity of compounds was examined against the human cervical cancer cell line, HeLa, and breast cancer cell line, MDA-MB-231, both in the dark and by light irradiation. Accordingly, both precursors and their ruthenium complexes were light-dependent toxic; nevertheless, di-iodinated meso-pyridine-substituted BODIPYs displayed light-independent toxicity by long-term treatments. Moreover, the effects of the complexes were cell-specific and the toxicities of di-iodinated BODIPY complexes were inversely correlated with the concentrations, underlying a possible aggregation and/or unpredicted cellular interaction pattern. These results emphasize that further functionalization and molecular characterization of BODIPY-ruthenium complexes are still required for PDT applications.
