Ilgın, Fatih Yavuz

It is clear that the future of wireless communication systems will face the problem of spectrum scarcity. Cognitive radio systems currently hold a significant position as a solution to this problem. Cognitive radios scan for spectrum gaps and make available for reuse of empty spectrum bands. In this study, we proposed a novel threshold for this method using a different cooperative spectrum sensing method with Standard Condition Number (SCN) for cognitive radios. Detailed simulation studies were included to evaluate the performance of the method. In the simulation studies, different eigenvalue-based sensing methods and energy-based sensing methods were compared using MIMO-OFDM based communication systems. The simulation studies proved the efficiency of the proposed cooperative method.

Çelik, Hüsamettin

The increase in data demand in mobile communication systems, parallel to the increase in the number of users, has led to serious problems encountered in the base station selection processes in 5G and beyond wireless networks. The distance between the base station and the user, and the signal attenuation caused by this distance, lead to poor signal quality and interference. Effective base station selection plays a critical role in improving the overall performance of communication networks. In traditional base station selection, the desired performance cannot be achieved because the maximum Received Signal Strength Indicator (RSSI) cannot optimize interference and load balancing. Based on these problems, this study created a realistic channel model for the 5G system using the 3GPP TR 38.901 channel model and addressed base station selection. This selection process was formulated using a multi-objective optimization method and solved with the Non-dominated Sorting Genetic Algorithm (NSGA-II). The simulation solution was obtained by considering the maximization of signal quality and the minimization of the distance between the base station and the user as the objective functions used in the NSGA-II algorithm. The results obtained showed that the proposed method provides more balanced and efficient solutions and increases the performance rate.

Kopar, İbrahim; Yanik, Muhammet Enes

Landslides, as one of the primary natural hazards, are significant mass movements that cause considerable casualties and property damage. The objective of this study is to perform a landslide susceptibility analysis of the Kara Dere Basin, located in the northwest of the Erzincan Plain, and to spatially delineate potential risk areas. In this research, the Analytic Hierarchy Process (AHP), a Multi-Criteria Decision-Making (MCDM) method, and Geographic Information Systems (GIS) technology were utilized. Within the scope of the model, eleven different landslide-conditioning parameters were evaluated: slope, precipitation, lithology, NDVI, slope curvature, distance to streams, land use, elevation, great soil groups, aspect, and distance to roads. As a result of the weighting process applied via the AHP method, slope (25.10%) and precipitation (19.20%) were identified as the most influential factors in landslide occurrence. For the validation of the susceptibility map produced, the historical landslide inventory in the study area was randomly partitioned, utilizing 70% as training data and 30% as independent testing data. The validation procedure, performed using the Receiver Operating Characteristic (ROC) curve and the Area Under the Curve (AUC) technique, yielded an AUC value of 0.799, demonstrating that the model possesses a scientifically acceptable and reliable predictive capacity. According to the spatial analysis results, it was determined that 43% of the basin consists of high and very high-risk areas, 34% of moderate-risk areas, and 23% of low and very low-risk areas. The most susceptible regions were identified as the high-gradient terrains in the north and northeast of the basin. Furthermore, while certain sections of the Erzincan-Kelkit highway were observed to be located in high-risk zones, it was verified that the Ahmetli Village disaster housing, constructed following a historical landslide event, is appropriately situated in a low-risk area. It is anticipated that the resulting susceptibility map will serve as a crucial scientific baseline for future regional and spatial planning, as well as disaster risk management strategies.

Üncü, İsmail Serkan; Isilak, Cemal; Gençtürk, Fatih

The pine processionary moth, widely found in Southern and Central Europe, North Africa, and the Middle East, causes significant economic and ecological losses in forests. This pest feeds on the needles of pine species, posing a greater threat than forest fires in Türkiye, where a large portion of the timber resource is made up of pine trees. This study aims to detect nests of the pine processionary moth residing on trees. A custom dataset was created using aerial images of infested pine trees. A deep learning model was trained using this dataset to facilitate nest detection. Using the YOLOv7 network, training and testing were performed on two datasets of different sizes. The analysis revealed that the dataset with a larger number of images yielded better performance in detecting pine processionary moth nests. The detection success of the model for nests was measured as 92.5% based on the mAP@0.5 metric. The findings of this study demonstrate the effectiveness of the proposed method for accurate and high-resolution detection of pine processionary moth nests in forestry applications. Moreover, these findings highlight the method’s potential to support pest density monitoring and the identification of intervention priority areas. Future research should investigate the applicability of the proposed approach to other pest species and explore its integration into real-time monitoring and pest management systems for large-scale operations.

Kose, Oguz

İnsansız hava araçları(İHA) son yıllarda popülerliği artan hava araçları olarak endüstriyel ve bilimsel çevrede dikkatleri üzerine çekmektedir. İHA’lar üzerinde bulundurduğu rotor sayısına göre isimlendirilir. Bu çalışmada döner kanat kategorisinde ve sekiz rotora sahip bir octorotor incelenmiştir. Çalışma kapsamında octorotor kol uzunlukları değiştirilerek(uzatılarak ya da kısaltılarak) başkalaşım uygulanmıştır. Başkalaşım, İHA’larda son yıllarda uçuş üzerine olan etkisinin incelenmesi konusunda araştırmacılar tarafından tercih edilen yöntem olmuştur. Başkalaşım döner kanatlı İHA’larda en yaygın olarak kol uzunluklarının eşzamanlı ya da eş zamanlı olmayan bir şekilde değiştirilmesi ile gerçekleştirilmektedir. Başkalaşımın boylamasına uçuşa olan etkisi yükselme zamanı, yerleşme zamanı ve aşım gibi parametreler kontrol edilerek incelenmiştir. Octorotor tam modeli ve başkalaşım durumuna ait dört adet modeli Solidworks çizim programında gerçeğine uygun olarak çizilmiştir. Ardından buradan elde edilen kütle ve eylemsizlik momenti değerleri ile durum uzay modeli yaklaşımı kullanılarak Matlab/Simulink ortamında 1ᵒ’lik yörüngeyi izleyen boylamasına uçuş simülasyonları oransal-integral-türev (PID) kontrol algoritması ile gerçekleştirilmiştir. Octorotor matematiksel modeli için Newton Euler yöntemi kullanılmıştır. Bu yöntemde doğrusal olmayan yapıya sahip hareket denklemleri doğrusal denklemlere dönüştürülmüştür. Simülasyonlarda verilen yörünge başarılı bir şekilde izlenmiş ve tasarım performans kriterlerine göre değerlendirmeler yapılmıştır.