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High-Performance Uv–vis–nir Photodetectors Based on Pedot Obtained by Plasma-Enhanced Chemical Vapor Deposition
No full textThis study presents the fabrication of organic UV–vis–NIR photodetectors based on poly(3,4-ethylenedioxythiophene) (PEDOT) thin films synthesized via a plasma-enhanced chemical vapor deposition at 10, 20, and 30 W plasma power. The effects of plasma power on polymerization, as well as optical, structural, morphological, and optoelectronic properties, are analyzed using UV–vis, Fourier transform infrared spectroscopy, scanning electron microscope, and scanning electron microscopy–energy-dispersive X-ray. The films, exhibiting a bandgap of 3.52–3.59 eV, are uniformly coated on Si surfaces. Photodiode and photodetector performance is evaluated through current–voltage and current–transient measurements under varying light intensities and wavelengths. PEDOT films synthesized at 10 W exhibit superior photodetector performance, with maximum responsivity and detectivity of 0.0975 A W−1 and 1.65 × 1010 cm Hz0.5 W−1 at 900 nm, and a noise-equivalent power of 5.38 × 10−12 W Hz−1/2. Maximum external quantum efficiency is recorded as 23.975% at 450 nm. These results emphasize the suitability of low-power PEDOT films for optoelectronic applications due to their superior morphology and optoelectronic characteristics. © 2025 Wiley-VCH GmbH
Usability of Waste Plastic Pyrolysis Liquid/Oil as a Flotation Collector in Wastewater Treatment
No full textPyrolysis is an important thermal waste disposal method that is more environmentally friendly than the combustion process, and almost all of its products can be converted into economic value. Specifically, the pyrolysis oils obtained are evaluated in different areas, such as the production of next-generation fuels and the recovery of valuable materials. Wastewater released during marble processing should not be discharged into the sewer without treatment, in accordance with national and international legislation, due to the high concentration of colloidal substances it contains. In the treatment of these wastewaters, conventional chemical precipitation processes and high amounts of synthetic chemicals are commonly used. Another method that can be employed for treating these wastewaters is the chemical substance-assisted flotation process, where efficiency depends on the use of oil-based chemicals. In this study, the treatment of marble processing wastewater was carried out for the first time using the flotation process, with pyrolysis oils obtained from mixed plastic waste pyrolysis as the collector material. According to the treatment experiments, the flotation collector that showed the highest suspended solid (SS) and turbidity removal efficiency was the pyrolysis oil obtained at a pyrolysis temperature of 700 degrees C. The flotation treatment findings were modeled using experimental design, and it was also revealed that collector dosage, mixing speed and air flow rate significantly affected the removal efficiencies
ZnO-In2O3-SnO2 Thin Film Transparent Heaters: Tunable Electrothermal Properties Through Substrate Temperature and Postgrowth Annealing
No full textAmorphous thin films of ZnO-In2O3-SnO2 (a-ZITO) were manufactured using magnetron sputtering technique for the applications of thin film transparent heaters (TFTHs). For this purpose, a custom-made 3” sputtering target was prepared with a specific composition in terms of the atomic percentages (at.%) of Zn, In, and Sn cations. The impact of varying substrate temperatures on the characteristics of the samples investigated by depositing the films on glass substrates maintained at room temperature, 150 °C, and 250 °C. To improve the optical and electrical properties, post-growth annealing was carried out under forming gas atmosphere at 400 °C. Structural, morphological, optical, and electrical properties of the samples were thoroughly examined. Electrothermal characterization was performed on samples at room temperature and -40 °C to evaluate response time, saturation temperature, thermal homogeneity, stability, recyclability, thermal resistance, and the defogging/deicing capability of the produced TFTHs. The films produced at 150 °C demonstrated an exceptional electrothermal response, with the thermal resistance calculated to be 181.7 °C·cm²/W under 12 V input. With a measured power density of 0.4635 Watt/cm², this heater was able to melt all ice and evaporate water droplets on the surface within 173 s, indicating a promising performance for commercial defogging/deicing applications
A New Approach for Calculating Texture Coefficients of Different Rocks With Image Segmentation and Image Processing Techniques
No full textThe texture coefficient (TC) is a critical parameter used to analyze the microstructural characteristics of rocks and predict their mechanical behavior. In recent years, various computational programs and software have been employed to estimate the TC values of rocks. However, existing methods remain insufficient and time-consuming for accurately determining rock TCs. In this study, thin-section images of 20 different igneous, metamorphic, and sedimentary rocks were acquired and segmented to calculate TC values using a novel approach. The computation process was implemented using Python-based software that integrates segmentation and image processing techniques to determine TC values. The thin-section images were segmented utilizing a deep learning-based image processing technique, and a Python-based algorithm was developed for TC calculations. The proposed method offers a unique approach to TC estimation in rocks, achieving a high segmentation accuracy (IoU = 0.97). Furthermore, with this method, the TC value of any given rock can be computed in approximately 1 min. © 2025 The Author(s). Microscopy Research and Technique published by Wiley Periodicals LLC.Konya Teknik Üniversitesi, KTUN, (221109027); Konya Teknik Üniversitesi, KTU
Investigation of the Effects of Rock Components for Different Pyroclastic Rocks on Leeb Hardness
No full textThe aim of this study is to research the effect of rock components on Leeb hardness (HL), a non-destructive test commonly used in recent periods. With this aim, cube samples of two different pyroclastic rocks containing dominantly pumice (P) or volcanic rock fragments (VRF) were prepared. Later, the proportions of different components (P and VRF) on the surfaces of the cube samples were determined using the Image Pro Plus 6.0 image processing program. The effect of the variation in these components on HL values was researched with simple regression analysis and strong correlation coefficients were found between these values. According to the data obtained, the HL test was identified not to be suitable for heterogeneous rocks comprising different components. © 2025, Budapest University of Technology and Economics. All rights reserved
Using Deep Learning Algorithms For Built-up Area Extraction From High-resolution Göktürk-1 Satellite Imagery
No full textBuilding extraction is a method used in high-resolution remote sensing image processing for urban planning and demographic analysis. This method plays a significant role in identifying urban structures and assessing damage in disaster situations. In this study, building extraction was performed using the U-net architecture with G ; ouml;kt ; uuml;rk-1 satellite imagery. This dataset was chosen because it has not been previously used in the literature for building extraction using deep learning methods. The impact of parameters such as the number of epochs, batch size, and learning rate on the results was evaluated. Additionally, the outcomes of the Adam (Adaptive Moment Estimation), SGD (Stochastic Gradient Descent), RMSprop (Root Mean Square Propagation), and Nadam (Nesterov-accelerated Adaptive Moment Estimation) optimizers were assessed. A training model was created using the Inria dataset, and the results were evaluated on G ; ouml;kt ; uuml;rk-1 satellite imagery. The findings indicated that increasing the number of epochs led to higher accuracy. The deep neural network model was applied to an urban area selected in Ankara using G ; ouml;kt ; uuml;rk-1 satellite imagery. Models for building segmentation and classification were both trained and tested. The results revealed that the U-net model achieved an overall accuracy of over 83.85% for building segmentation with the Adam optimizer. The intersection over union (IoU) ranged between 96 and 99%. The highest Dice similarity value (88.81%) was obtained with the RMSprop optimizer at 100 epochs
A Binary Grasshopper Optimization Algorithm for Solving Uncapacitated Facility Location Problem
No full textThe Uncapacitated Facility Location Problem (UFLP) is a real-world binary optimization problem that aims to find the number of facilities to open, minimizing the total cost of exchange between customers and facilities, as well as the opening costs of these facilities. UFLP is classified as an NP-Hard problem. Metaheuristic methods are often preferred to solve UFLP due to their ability to find acceptable solutions in a reasonable time and its NPHard characteristics. Grasshopper Optimization Algorithm (GOA) is a continuous metaheursitics optimization algorithm. In the literature, although some binary versions of the GOA algorithm have been used to solve problems such as feature selection, knapsack, scheduling and cluster covering, its performance analysis has not been conducted on UFLP which is pure binary optimization problem. In this study, a novel binary version of the GOA integrated with a novel binarization procedure is proposed for solving the UFLP. In the binarization procedure, a probability-based update strategy has been developed for generating new candidate solutions. This approach ensures the probability of determining the effect of the global best solution on the candidate solution. Besides, during the population update phase, there are two different mechanisms to update the global best solution and other grasshoppers. To enhance diversity in the grasshopper population, an alpha parameter has been integrated into the original algorithm. It was aimed to improve the quality of the candidate solutions by the integration of the alpha parameter. The performance of the proposed algorithm is assessed on the CAP and M* datasets. The obtained GAP values for the CAP 71-CAP A, CAP B, and CAP C problems are 0, 0.14, and 0.18, respectively. The GAP is 0 for the MO1-MO5, MP2, MP3, and MQ1-MQ3 problems, and GAP = 0.24 for the remaining problems. The results were compared with other state-of-the-art binary optimization algorithms. The experimental results show that the proposed method is superior to the other compared algorithms and is an effective algorithm for solving UFLPs.This study has been supported by the Scientific Research Project at Konya Technical University, Konya, Turkiye (Project No: 231113067).Scientific Research Project at Konya Technical University, Konya, Turkiye [231113067
Mermer Çamuru Katalizörü ile PET/PP Plastiklerin ve Zeytin Posası Biyokütlesinin Katalitik Ko-pirolizi
No full textSürdürülebilir ve etkili atık yönetimi, çeşitli atık türlerine simbiyotik çözümlerin dahil edilmesini ve böylece dairesel ekonomiye ulaşılmasını gerektirir. Bu motivasyonla, bu çalışmada, plastiklerin, biyokütlenin ve mermer işleme atıklarının fizikokimyasal arıtma çamurunun (K1) kombine termokimyasal dönüşümü (pirolizi) incelenmiştir. Bu kombinasyonda, plastikler petrol bazlı sentetik aromatik (PET) ve alifatik (PP) organikler iken, zeytin posası-OP doğal tarımsal kalıntıdır. K1, literatüre ilk olarak yazarlar tarafından piroliz katalizörü olarak tanıtılan mineral üründür. Çalışmada, polimerlerin ve biyokütlenin eş pirolizi, CaCO3 içeren mineral atık tarafından katalize edilmiştir. Plastik türünün ve pirolize edilmiş malzeme karışım oranının piroliz fraksiyonları üzerindeki etkisi araştırılmıştır. Ayrıca, piroliz fraksiyonlarından malzeme geri kazanım potansiyeli tartışılmıştır. Katalitik ko-pirolizde, karışımdaki plastik oranının artırılmasıyla pirolitik sıvı ve oligomer fraksiyonu artarken katı (char) ve gaz fraksiyonu azaldı. %70PP+%15OP+%15K1 karışımı için sıvı ürün baskındı, %60PET+%20OP+%20K1 ile ise çok daha fazla pirolitik gaz fraksiyonu üretildi. Char ürünlerinin termal bozunması 600°C'ye kadar %2-3'ü geçmedi ve bu kararlılık yaklaşık 700°C'ye kadar devam etti, char'ın yüksek termal dirence sahip bir malzeme olarak alternatif alanlarda kullanılma potansiyelini ortaya koydu. Katalitik ko-piroliz sıvı ürünleri alkanlar, alkenler, asitler, fenoller, benzen, aldehitler, esterler, alkoller, ketonlar içerir. Sıvılarda benzen, asit ve alkol grupları baskınken, gazlarda alkan, alken ve alkin grupları baskındı
Digital Documentation of a Byzantine Rock-Carved Structure in Konya: Kiriakon Monastery, Sille
No full textDigital documentation methods enable the acquisition of viable data to preserve cultural heritage and its accurate transfer to future generations. Unmanned aerial vehicle (UAV) and terrestrial laser scanning (TLS) equipment are technical tools that have essential functions in the three-dimensional (3D) modeling of structures of historical importance. In the geographic referencing and visualization of historical structures with their surroundings, UAVs are often used, and for the visualization of the interior spaces of structures as a whole, TLS is popular. The Kiriakon Monastery, a rock-carved, cross-in-square, four-supports simple provincial type of church, and several different structures around it within the borders of Sille in Konya Province are investigated in this study. As one of the essential rock-carved monasteries in the Lycaonia region, the Kiriakon Monastery, which was designed around a courtyard and features spaces carved into the rock, is one of the most important Middle Byzantine period structures that have survived to the present day in Sille. Although both time and external factors have damaged the church section of the monastery, it reveals the richness of Byzantine period rock-carved church decoration designs with rich relief decorations. The Kiriakon Monastery, which is being increasingly damaged with time, does not have smooth geometric surfaces and consists of rock-carved spaces, and so documentation studies cannot be performed reliably with classical measurement methods. Instead, the Kiriakon Monastery can be evaluated as an important part of the historical cultural heritage of Anatolia, mainly containing rock-carved spaces from the Byzantine period, through documentation based on measurements obtained with the help of technological methods that are subsequently transferred to a digital environment. In this study, the digital documentation of Sille’s Kiriakon Monastery was georeferenced using UAV technology. Interior 3D models of the structure were created from TLS data and then integrated with the interior and exterior surface data
Enhanced Performance of Mxene-Based Supercapacitor Via New Activated Carbon-Nafion Composite Cathode
No full textAsymmetric supercapacitors leverage differences in the work functions of electrode materials to achieve an extended operating potential window and enhanced energy storage capacity. In this study, an asymmetric supercapacitor was developed using Ti3C2Tx MXene as the working electrode and a composite of activated carbon-nafion (AC-N) and activated carbon-polyvinylidene fluoride (AC-P) as the counter electrode. The work functions of MXene and AC-N were measured as 7.06 and 9.6 eV, respectively, enabling a potential window expansion to 2 V with the AC-N counter electrode. Electrochemical evaluations in H2SO4, MgSO4, and KOH electrolytes revealed specific capacitance values of 555, 367.5, and 425 F g-1 in, respectively. Additionally, corresponding power densities reached 1023, 999.86, and 1980.25 W kg- 1 , while energy densities were determined to be 81.2, 40.55, and 26 Wh kg- 1 . These findings highlight a straightforward strategy to enhance energy storage performance by leveraging the distinctive properties of MXene.All authors contribute equally to this work. This research was sup-ported by The Scientific and Technological Research Council of Turkey (No. 221M523) and Konya Technical University Scientific Research Projects (Grant No. 221016030) .Scientific and Technological Research Council of Turkey [221M523]; Konya Technical University Scientific Research Projects [221016030