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Design, modelling and control of an eight-rotors uav with asymmetric configuration for use in remote sensing systems
(Vedat Veli ÇAY, 2021) Çabuk, Nihat; Yıldırım, Şahin
The use of multirotor unmanned aerial vehicles (UAV), which can take-off and landing vertically, is gradually expanding. Although there are many types of these vehicles with standard configuration, non-standard configurations may be required for special purposes usage. So, an octocopter UAV with asymmetric configuration is proposed in this study. In particular, this asymmetrically configured octocopter is intended to be used for imaging or mapping purposes, and may be a solution to widen the viewing angle of the camera or any sensor placed on the vehicle, especially in the use of multiple cameras and sensors. The mathematical model of this proposed UAV system was obtained and the trajectory tracking was performed using PID control method. The control parameters of the controller were determined using Grey Wolf Optimizer (GWO). Considering the propellers determined in two different sizes due to its asymmetrical structure, it has been observed that the proposed UAV performs a satisfactory trajectory tracking.
Bacaklı robotların yürüme stratejileri üzerine bir literatür taraması
(Gazi Üniversitesi, 2020) Bakırcıoğlu, Veli; Kalyoncu, Mete
Bu çalışmada, ayaklı hareket üzerine yapılan geçmiş dönem araştırmalara; özellikle, ayaklı robotlar literatürünün önemli kilometre taşlarına değinilmiştir. Geçmiş dönem araştırmalardan, öncelikle canlıların yürüyüşü ve bunu taklit edebilen makineler üzerine yapılan çalışmalardan bahsedilmiştir. Daha sonra, çalışmanın konusu olan ayaklı robotların tarihçesi ele alınmıştır. Ayaklı robotlar üzerine yapılan çalışmalarda, yürüyüş stratejisi olarak iki temel yaklaşım söz konusudur; statik yürüyüş ve dinamik yürüyüş. Bu sebepten dolayı ayaklı robotlar tarihçesi, Statik Yürüyen Ayaklı Robotlar ve Dinamik Yürüyen Ayaklı Robotlar olmak üzere iki temel başlık altında kronolojik sırayla anlatılmıştır. Statik Yürüyen Ayaklı Robotlar başlığında, engebeli yüzeylerde hareket ve engelleri aşma gibi arazi adaptasyonunun daha karmaşık problemleriyle başa çıkmak için çok bacaklı sistemlerin kontrol edilmesine yönelik tekniklerin geliştirilmesi üzerine yapılan araştırmalar; Dinamik Yürüyen Ayaklı Robotlar başlığında ise, koşma ve zıplama gibi oldukça gelişmiş hareket kabiliyetlerine sahip ayaklı sistemler geliştirebilmek için dinamik kontrol kavramlarının ve tekniklerinin ilerletilmesi üzerine yapılan araştırmalar sunulmuştur.
Microplastic-associated biofilms in a river catchment: Diversity, public health impact, and ecosystem risks
(Elsevier, 2025) Çelik, Işılay; Fırat, Müge; Çırak, Tamer; Başaran Kankılıç, Gökben; Dalgıç, Açelya; Ürker, Okan; Keskin, Emre; Tavşanoğlu, Ülkü Nihan
Microplastics (MPs) serve as vectors for microbial colonization and biofilm formation, posing risks to aquatic environments and public health. This study investigated the seasonal dynamics of biofilm-forming microorganisms in the Melen River catchment - a vital water source for the cosmopolitan city of İstanbul - using an environmental DNA (e-DNA) approach, which analyzes genetic material present in the environment to detect and study organisms. Polyethylene (PE) and polypropylene (PP) were the most prevalent polymers year-round, supporting the attachment of bacterial genera such as Acinetobacter, Pseudomonas, Flavobacterium, Paludibacter, and Undibacterium. A total of 70,366 and 83,327 genera were identified from water and MPs samples, respectively. The presence of pathogens such as Acinetobacter and Flavobacterium on MPs underscores significant threats to public health and aquatic food webs. Functional predictions made using PICRUSt2, a bioinformatics tool that infers metabolic pathways from 16S rRNA gene sequences, suggested that biofilm-forming bacteria on plastic surfaces may be involved in fermentation, vitamin biosynthesis, nucleoside and nucleotide degradation, and secondary metabolite degradation. These findings provide crucial insights into the ecological and health risks associated with MPs, emphasizing the role of these particles in harboring pathogens, influencing biofilm formation, and contributing to plastic degradation. This study highlights the urgent need to address MPs contamination in freshwater ecosystems to mitigate its environmental and public health risks within the framework of the 'One Health' approach.
Atmospheric microplastic dispersion in diverse land-use context: insight from the black sea coastal region in Türkiye
(Springer Science and Business Media B.V., 2025) Ertürk Arı, Pelin; Erdoğan, Şeyda; Arı, Akif; Ürker, Okan; Başaran Kankılıç, Gökben; Çırak, Tamer; O. Gaga, Eftade; Tavşanoğlu, Ülkü Nihan
The atmospheric deposition of microplastic particles is a critical pathway for their input into the environment; however, available information remains limited. This study investigates atmospheric microplastics across urban, suburban, and rural areas in the humid/subtropical climate region of Black Sea coastline, specifically Düzce, Türkiye. The highest mean total microplastic deposition fluxes were recorded during the winter season, highlighting the influence of seasonal factors, such as meteorological conditions, on microplastic deposition. Fibers were the dominant type of microplastics (84%), with the primary colors being black, red, blue, and white/transparent with predominantly 0.5–1 mm in size range. During the winter period, characterized by heavy precipitation and peak microplastic depositions rates, dominant air mass trajectories pointed towards Eastern Europe and the Black Sea regions. In contrast, during the summer season, with lower deposition rates and minimal precipitation, the prevailing air trajectories predominantly originated from Northern Europe, Scandinavia, and Russia, moving in northwestern and northeastern directions. While this study provides evidence of microplastic deposition and transport, it is crucial to address significant uncertainties arising from variations in sampling methodologies. Factors such as sampling height, sampler size, sampling duration, and seasonal differences can impact results and complicate comparisons across studies. Therefore, further investigations are necessary to resolve these methodological discrepancies and to gain a more comprehensive understanding of the implications of atmospheric microplastics on human and ecosystem health, particularly from a One Health perspective.
Multi-Objective optimization and thermodynamic analysis of a supercritical CO2 Brayton cycle in a solar-powered multigeneration plant for net-zero emission goals
(Elsevier Ltd, 2025) Bakırcıoğlu, Veli; Yılmaz, Fatih; Jond, Hossein B.
The development, design, examination, and optimization of carbon-free power generation models are essential to achieve a sustainable future with net-zero emissions. This study introduces a novel multigeneration system, uniquely combining a supercritical CO2 Brayton cycle and a transcritical CO2 Rankine cycle, supported by a solar parabolic trough collector. The system integrates a reverse osmosis desalination unit, enabling simultaneous production of clean water, heating, and power. A multi-objective optimization framework is implemented by the NSGA-II algorithm, coupled with the TOPSIS method, to explore and identify optimal operational conditions. The innovation lies in the comprehensive consideration of solar incident angles and their impact on system performance, a rarely addressed aspect in the literature. Detailed thermodynamic analysis highlights system performance, achieving a net power capacity of 1052 kW, freshwater generation of 90.44 m3/h, and hot water generation of 1614 kW. The optimized results demonstrate significant improvements in overall energy (50.28 %) and exergy efficiency (22.31 %), showcasing the system's potential as a benchmark for sustainable, zero-emission energy solutions.
Increasing microplastics pollution: An emerging vector for potentially pathogenic bacteria in the environment
(Elsevier Ltd, 2025) Tavşanoğlu, Ülkü Nihan; Akça, Gülçin; Pekmez, Tülay; Başaran Kankılıç, Gökben; Çırak, Tamer; Çağan, Ali Serhan; Özkan Kotiloğlu, Selin; Grossart, Hans-Peter
Microplastics (MP), plastic particles <5 mm, are of global concern due to their worldwide distribution and potential repercussions on ecosystems and human well-being. In this study, MP were collected from the urbanized Susurluk basin in Türkiye to evaluate their vector function for bacterial biofilms, both in the wet and dry seasons. Bacterial biofilms were predominantly found on polyethylene (PE), polypropylene (PP), and polystyrene (PS), which constitute the most common MP types in the region. Specific potentially pathogenic bacterial genera, including Pseudomonas sp., Comamonas sp., Salmonella spp., and Shigella spp., were prevalent on MP surfaces. Notably, PE and PP harboured numerous genera of potential human and/or animal origin such as Staphylococcus, Proteus, Escherichia, Enterococcus, and Enterobacter. Water quality played a pivotal role in bacterial biofilm formation on MP. Higher salinity in estuarine areas reduced bacterial abundance on MP, while the more polluted freshwater Nilüfer Stream harboured a higher abundance of total bacteria, particularly of potentially pathogenic strains. Seasonal variations, ambient water conditions, and polymer type are all factors that could influence bacterial colonization on MPs. This catchment-wide evaluation, which includes various habitat types (lentic and lotic systems), the enrichment of cultivable viable bacteria on microplastics (MPs) - a key factor in the spread of pathogens - has significant implications for both environmental and public health. Unlike controlled laboratory experiments or in-situ studies with various particles, this study emphasized the dynamic and complex nature of bacterial strains on MPs, which varied depending on seasonal dynamics and antropogenic impacts in open systems. Further research is needed to thoroughly investigate to fully explore the complex interactions among MPs, microbial communities, and their ecological roles, especially in the context of changing environmental factors across entire river catchments.
Optimization-driven design and experimental validation of a hydraulic robot leg mechanism
(2025) Bakırcıoğlu, Veli; Çabuk, Nihat; Jond, Hossein B.; Kalyoncu, Mete
Hydraulic-actuated legs for quadruped robots excel in producing high force and offering precise control. Although the overall efficiency of hydraulic servo systems can be limited by pump and valve losses, the local mechanical efficiency from the actuator to the leg mechanism can be relatively high. This study introduces an optimization driven methodology for designing and validating robotic leg mechanisms using evolutionary algorithms. By solving three distinct optimization problems, the study addresses trajectory tracking accuracy and force transmission efficiency. The resulting design was experimentally validated, demonstrating reliable motion reproduction with minimal deviation and achieving a force transmission efficiency of 94%. These results demonstrate the feasibility of translating optimization outcomes into high-performing physical prototypes, providing a robust framework for future robotic mechanism developmen
Enhanced Total Harmonic Distortion Optimization in Cascaded H-Bridge Multilevel Inverters Using the Dwarf Mongoose Optimization Algorithm
(Department of Agribusiness, Universitas Muhammadiyah Yogyakarta, 2024) Salih, Sinan Q.; Mejbel, Basim Ghalib; Ahmad, B.A.; Taha, Taha A.; Bektaş, Yasin; Aldabbagh, Mohammed M.; Hussain, Abadal-Salam T.; Hashim, Abdulghafor Mohammed; Veena, B.S.
Total harmonic distortion (THD) is one of the most essential parameters that define the operational efficiency and power quality in electrical systems applied to solutions like cascaded H-bridge multilevel inverters (CHB-MLI). The reduction of THD is crucial due to the fact that improving the system’s power quality and minimizing the losses are key for performance improvement. The purpose of this work is to introduce a new DMO-based approach to optimize the THD of the output voltage in a three-phase nine-level CHB-MLI. The proposed DMO algorithm was also subjected to intense comparison with two benchmark optimization techniques, namely Genetic Algorithm and Particle Swarm Optimization with regards to three parameters, namely convergence rate, stability, and optimization accuracy. A series of MATLAB simulations were run to afford the evaluation of each algorithm under a modulation index of between 0.1 and 1.0. The outcome of the experiment amply proves that in comparison with THD minimization for the given OP, the DMO algorithm was significantly superior to both RSA-based GA and PSO algorithms in their ability to yield higher accuracy while requiring lesser computational time. Consequently, this work could expand the application of the DMO algorithm as a reliable and effective means of enhancing THD in CHB-MLIs as well as advancing the overall quality of power systems in different electrical power networks.
The comparison study of PI and Sliding Mode control techniques for Buck-Boost converters
(Niğde Ömer Halisdemir Üniversitesi, 2024) Al-Attwani, Salah Hilo; Teke, Mustafa; Bektaş, Enes; Yaseen, Ethar Sulaiman Y.; Bektaş, Yasin; Civelek, Zafer
This paper compares the performance of a Sliding Mode Control (SMC) and Proportional-Integral (PI) controller under different voltage and load conditions. The study's findings underscore the need to account for load variations in system designs and to continuously seek system optimization irrespective of the controller type chosen. PI controller demonstrates effectiveness under certain circumstances. However, significant drops in voltage and current during abrupt load changes are obtained. On the other hand, SMC enables superior adaptability, efficiently managing voltage transients and load variations without any electrical disturbances, thereby maintaining system stability. A comparative analysis further emphasizes the SMC's superior time response and robustness against reference voltage changes. Consequently, SMC is proven to be a preferable choice over the PI controller in systems experiencing frequent voltage and load variations. However, both controllers achieve the potential for further response time optimization and stability.
Enhanced transformer protection using fuzzy-logic-integrated differential relays: a comparative study with rule-based methods
(Department of Agribusiness, Universitas Muhammadiyah Yogyakarta, 2024) Hussein, Raad Ibrahim Hussein; Gökşenli, Nurettin; Bektaş, Enes; Teke, Mustafa; Tümay, Mehmet; Yaseen, Ethar Sulaiman Yaseen; Bektaş, Yasin; Taha, Taha A.
The power transformers are the important part of electrical networks where transformer reliability and operational lifetime depends on sufficiently accurate and reliable protective means. Other traditional forms of differential protection that were developed initially also suffer from the inability to distinguish between a fault and normal operation such as inrush currents in transformers and CT saturation. This paper presents the development of an improved differential relay augmented by Fuzzy-Logic Control System (FLC), to improve (a) dependability, (b) performance of the existing transformer protection systems, and (c) accuracy in fault identification possible due to uncertainty and non-linearity in transformer operation. They include the proposed methodology compared to the traditional Rule-based current differential method in outlining the protection settings. MATLAB/Simulink model of the power transformer and protection methods suggested in the study form a part of the investigation. Computer simulations show that the presented scheme provides a substantial increase in the speed and resolution of fault detection and fault types identification relating to current differential method based on the Rule. The system’s accuracy rate is the average of 98% for internal faults and 95% for external faults while its response time is 25ms for internal faults and 30ms for external faults. Furthermore, the Fuzzy-Logic-based system has an 90% efficiency in detect the defect and 85% efficiency in identify the inrush currents. The findings of this research prove that the differential relay based on Fuzzy-Logic enhances the flexibility and reliability of transformer protection and opens the road to the introduction of further improvements in the intelligent protection systems in the future.
Effect of heat treatment on microstructure of near-eutectic Al-Ni-Mn alloy, and determination of mechanical and thermoelectrical properties
(Institute of Physics, 2024) Kaygısız, Yusuf
This study examined the impact of solution heat treatment on the microstructure, mechanical characteristics, thermophysical properties, and electrical resistivity of an Al-Ni-Mn near-eutectic alloy. The investigation focused on varying temperatures and holding periods. The composition of the Al-Ni-Mn near-eutectic alloy system was chosen as Al-5.3%Ni-1.0%Mn (wt). In the non-heat-treated sample, the matrix phase (?-Al) is in equilibrium with the intermetallic Al9(Mn,Ni)2 and Al3Ni phases. The hardness value of the non-heat-treated sample (49.8 kg mm?2) increased to 70.1 kg mm?2 with 2 h of solution heat treatment at 570 °C and then 8 h of artificial aging at 180 °C. The hardness value increased by approximately 41%. TE: 651.81 °C for the non-heat-treated sample and TE:648.79 °C for the heat-treated sample. Fusion enthalpy (?H) value was determined as 336.79 (J g?1) for the non-heat-treated sample and 516.36 (J g?1) for the heat-treated sample. Heat Capacity (Cpl) value was found to be 0.364 J g?1.K for the non-heat-treated sample and 0.560 J g?1.K for the heat-treated sample. The electrical resistivity value of the 2 h’ solution heat-treated sample at 600 °C reached its highest value.
Assessing microplastic pollution in a river basin: A multidisciplinary study on circularity, sustainability, and socio-economic impacts
(Academic Press Inc., 2024) Tavşanoğlu, Ülkü Nihan; Koraltan, İdris; Başaran Kankılıç, Gökben; Çırak, Tamer; Ertürk, Şeyma; Ürker, Okan; Güçlü, Pembe; Ünlü, Hülya; Çağan, Ali Serhan; Deniz Yağcıoğlu, Kıymet; Akyürek, Zuhal
Plastic pollution has emerged as a significant environmental challenge worldwide, posing serious threats to ecosystems and human health. This study seeks to explore the interplay among circularity, sustainability, and the release of microplastics within the freshwater ecosystems situated along the western Black Sea coast- Düzce, Türkiye. Employing a multidisciplinary approach that integrates environmental science, economics, and policy analysis, the research examines the current state of plastic pollution in the region, considering diverse land uses and socio-economic lifestyles. Conducted over four different seasons, the current study identifies the prevailing types of microplastics in the region. Fibers dominate, comprising 86.7% in each season, followed by film and fragments at 7.7% and 7.0%, respectively. Notably, polyethylene (PE) and polypropylene (PP) emerges as the primary polymer types. The distribution of polymer types varies across different land uses within the region, emphasizing the influential role of land use in shaping the abundance polymer composition. The comprehensive assessment of pollution, as reflected in the overall pollution load index (PLI) of the Melen River indicating a concerning level of pollution (PLI>1). Finally, the study unveiled the relationship between socio-economic activities as well as the seasonal precipitation patterns, and microplastic contamination in the region. This underscored the importance of site-specific mitigation measures on reducing the amount of microplastics. Lastly, incorporating sustainable practices within the circular economy framework fosters a harmonious balance between economic development and environmental protection in Türkiye.
Enhancing Multilevel Inverter Performance: A Novel Dung Beetle Optimizer-based Selective Harmonic Elimination Approach
(Department of Agribusiness, Universitas Muhammadiyah Yogyakarta, 2024) Taha, Taha A.; Neamah, Muthanna İbrahim; Ahmed, Saadaldeen Rashid; Taha, Faris Hassan; Bektaş, Yasin; Desa, Hazry; Yassin, Khalil Farhan; İbrahim, Marwa; Hashim, Abdulghafor Mohammed
This paper introduces a novel approach for enhancing the performance of multilevel inverters by applying a dung beetle optimizer (DBO)-based Selective Harmonic Elimination (SHE) technique. Focusing on a 3-phase multilevel inverter (MLI) with a non-H-bridge structure, the proposed method offers advantages such as cost-effective hardware implementation and eliminating the traditional H-bridge inverter requirement. To assess its efficacy, we compare the presented DBO-based SHE technique (DBOSHE) with Genetic Algorithm (GA) and Particle Swarm Optimization (PSO), evaluating their ability to determine optimal switching angles for achieving low-distorted load voltage. Unlike methods reliant on time-consuming calculations or fixed solutions, DBO provides a flexible approach, considering multiple possibilities to yield accurate switching angles. Using Simulink, harmonic component values and Total Harmonic Distortion (THD) are obtained for each optimization technique, specifically emphasizing on 9-level and 11-level MLI topologies. Our study aims to identify the most effective optimization technique for achieving lower THD and THDe values while eliminating odd-order harmonics from the 3-phase load voltage. Finally, we demonstrate the effectiveness of employing DBO for THD and THDe optimization within the SHE technique.
Dandelion Optimizer and Gold Rush Optimizer Algorithm-Based Optimization of Multilevel Inverters
(Springer Nature, 2024) Sağlam, Mustafa; Bektaş, Yasin; Karaman, Ömer Ali
With the increasing integration of renewable energy sources into distribution and transmission networks, the efficiency of cascade H-bridge multilevel inverters (MLIs) in power control applications has become increasingly significant for sustainable electricity generation. Traditionally, obtaining optimal switching angles of MLIs to minimize total harmonic distortion (THD) requires solving the selective harmonic elimination equations. To this end, this research aims to use two recently developed intelligent optimization algorithms, dandelion optimizer and gold rush optimizer, to solve this problem. To evaluate the effectiveness of the proposed algorithms, an eleven-level cascaded H-bridge MLI (CHB-MLI) was considered in the study. Simulation results for different modulation indices were obtained, and the accuracy and solution quality were compared with genetic algorithm and particle swarm optimization algorithms. MATLAB/Simulink-based models were used to verify numerical computations, ensuring the reliability of the findings. This research contributes to the field by providing insights into obtaining optimal switching angles and minimizing THD in MLIs by applying intelligent optimization algorithms.
Real-time control of Selective Harmonic Elimination in a Reduced Switch Multilevel Inverter with unequal DC sources
(Ain Shams University, 2024) Bektaş, Yasin
This study proposes a two-step method for generating switching angles in renewable energy systems that use multi-level inverters (MLIs) to reduce low-order harmonics. The Selective Harmonic Elimination Pulse Width Modulation (SHE-PWM) technique is used for MLI control, but it can be computationally intensive for real-time applications. To address this challenge, the proposed approach consists of a two-stage process. In the first stage, the SHE equations are solved offline using artificial ecosystem-based optimization (AEO). The obtained switching angles are then used to train an artificial neural network (ANN) prediction model in the second stage. The AEO-ANN-based SHE-PWM technique is applied to a reduced-switching, 3-phase, 7-level MLI. Simulations in MATLAB/SIMULINK show that the proposed method achieves accurate voltage control with less than 0.2% error, even for changing voltages, and reduces selected harmonics to less than 0.05%. The desired output voltage exhibits minimal total harmonic distortion (THD). This method offers a promising way to generate switching angles in renewable energy systems that use MLIs, improving power quality and reducing harmonic distortion.
Effect of heat treatment on corrosion resistance of al-ni-mn eutectic alloy in 3.5% nacl solution
(Konya Teknik Üniversitesi, 2024) Kaygısız, Yusuf
In this study, the effects of solution heat treatment (SHT) on how the Al-Ni-Mn eutectic alloy reacts to corrosion were looked into. The composition of the Al-Ni-Mn eutectic alloy was chosen as Al–5.3%Ni–1.3%Mn (wt). In solution heat treatment, firstly, the samples were kept at 570oC and 600oC for 2 hours and quenched with water at room temperature. Then, artificial aging was carried out by keeping 0-2-4 and 8 hours at 180oC. The corrosion behavior of the alloy was investigated by immersion tests in a 3.5% NaCl solution and electrochemical methods such as Tafel polarization curves and Electrochemical Impedance Spectroscopy (EIS). According to the immersion test results, the heat treatment applied at 600oC took the alloy to the more noble side and further increased its corrosion resistance. The ?-Al matrix phase in the Al-Ni-Mn alloy system preferentially dissolves in untreated and heat-treated samples, and SEM images reveal the presence of corrosion pits. The corrosion performance of the heat-treated sample at 570oC is the highest. Heat treatment reduced the corrosion current density, indicating a lower corrosion rate and higher corrosion resistance. Also, the open circuit potential of the Tafel polarization curves of heat-treated and unheat-treated samples at 570oC and 600oC was found to be -685 mV, -693 mV and -761 mV, respectively. Similarly, the corrosion resistance of heat-treated and untreated samples at 570oC and 600oC was found to be 58 k?, 433 k? and 408 k?, respectively.
Determination of microstructure and mechanical and thermophysical properties of Al-Si-Mg-XCr alloy
(Elsevier, 2024) Kaygısız, Yusuf; Palta, Çetin; Engin, Sevda
The study added different proportions of Cr to the Al-Si-Mg eutectic alloy and applied heat treatment to the quaternary alloy. So, the Al-Si-Mg eutectic alloy's microstructure and morphology were looked at after Cr was added and it was heated. In addition, the hardness, tensile strength, fracture surface analysis, and thermoelectric properties of newly produced Al-12.95 % Si-4.96 % Mg-X%Cr alloys were also determined. In the newly formed alloy, along with the expected Si and Mg2Si phases in the Al matrix phase, a randomly distributed CrSi2 binary intermetallic phase in a white hexagonal structure was observed with the effect of Cr addition. Additionally, a magnesium-rich Al9FeMg3Si5 intermetallic phase was observed, which we think was formed by the effect of Fe impurity atoms. Hardness and tensile strength values, which are the mechanical properties of the alloy, increased significantly after heat treatment. The hardness value of the 0.5 % Cr-added sample increased by approximately 77 % and reached 107.95 +/- 6.0 kg/mm2. At the same time, the hardness value of the intermetallic CrSi2 phase in the quaternary Al-12.95 wt%Si-4.96 wt%Mg-1.0%Cr alloy was found to be 794.3 +/- 30 kg/mm2. Similarly, the maximum tensile strength value of the 0.5 % Cr-added sample after heat treatment increased by approximately 105 % and reached 160.53 MPa. Melting temperatures (Tm) (K), fusion enthalpy (Delta H) (J/g), and specific heat Cpl (J/gK) were determined for non-heat-treated materials. The 0.5, 1.0, and 1.5 Cr-added samples had Tm of 563.38 degrees C, 558.44 degrees C and 572.61 degrees C, respectively. The Delta H value of samples with 0.5 %, 1.0 % and 1.5 % Cr addition is 605.70 (J/g), 579.92 (J/g) and 552.24 (J/g), respectively. Cpl was 0.724 J/g.K, 0.698 J/g.K and 0.653 J/g.K for 0.5 %, 1.0 %, and 1.5 % Cr-added samples. In both heat-treated and non-heat-treated samples, Cr enhanced electrical resistance.
The Effect of Mn Addition and Heat Treatment on the Microstructure, Mechanical, and Thermophysical Properties of Al-Si-Mg Eutectic Alloy
(Springer Science and Business Media Deutschland GmbH, 2024) Kaygısız, Yusuf; Palta, Çetin; Kaymaz, Tuba Çifçi; Engin, Sevda
The study added Mn at different rates to the Al–Si–Mg eutectic alloy and heat-treated the quaternary alloy. Therefore, the microstructure morphology of the Al–Si–Mg eutectic alloy was examined after Mn addition and heat treatment. Also determined were the hardness, tensile strength, fracture surface analysis, and thermoelectric characteristics of the newly produced Al–12.95%Si–4.96%Mg–X%Mn [X=0.5, 1.0, and 1.5 (wt.)] alloys. Along with the predicted Si and Mg2Si phases in the Al matrix phase, this investigation found a randomly distributed Mn-rich Al15Mn3Si2 intermetallic phase and a Mg-rich Al5Si3Mg2 phase. Mn-doped samples without heat treatment were somewhat softer than the parent alloy. After heat treatment, the hardness more than doubled for the Al–Si–Mg eutectic system and Mn-doped samples. After heat treatment, the alloy with 1.5% Mn added had the maximum hardness value of 94.3±5.0 HV. Heat treatment improved tensile strength by up to 80%, and the alloy with 0.5% Mn had 144.7 MPa. Melting temperatures (Tm) (K), fusion enthalpy (?H) (J/g), and specific heat Cpl (J/gK) were determined for non-heat-treated materials. The 0.5, 1.0, and 1.5 Mn-added samples had Tm of 566.30, 568.96, and 566.40 °C, respectively. The ?H value of samples with 0.5%, 1.0% and 1.5% Mn addition is 662.29, 657.93 and 639.11, respectively. Cpl was 0.788, 0.781, and 0.761 J/g.K. for 0.5%, 1.0%, and 1.5% Mn-added samples. In both heat-treated and non-heat-treated samples, Mn enhanced electrical resistance.
Makine Öğrenmesi ve Optimizasyon Yöntemleri ile Uzun Dönem Elektrik Enerjisi Tahmini: Türkiye Örneği
(Bandırma Onyedi Eylül Üniversitesi, 2023) Kahraman, Ömer Ali; Bektaş, Yasin
The rapid spread of industrialization has increased the need for energy today. However, optimization and machine learning algorithms have come to the fore in order to make predictable energy estimates in order to meet this emerging energy need. Particle swarm optimization (PSO), Lineer Regresyon (LR) and support vector regression (SVR) are included in these algorithms. In this study, using PSO, LR and GSR algorithms, Turkey's energy demand estimation between the years 2020-2040 was carried out. In order to make these estimations, the past population, exports, imports, gross domestic product (GDP) between 1980-2019 were used as input data, while energy consumption was used as output data. Regression square (R2) value, root mean square error (RMSE), mean square error (MSE), and mean absolute error (MAE) error metrics were used to evaluate the performance results of the PSO, LR, and GSR methods. Considering the R2, RMSE, MSE and MAE values, it has been determined that all methods have successful results. Anahtar Kelime: Particle Swarm Optimization Linear Regression Gaussian Process Regression Energy Demand Forecasting
Child tracking system using smartphone
(Institute of Advanced Engineering and Science, 2023) Taha, Taha A.; Hussain, Abadal-Salam T.; Desa, Hazry; Taha, Faris Hassan; Bektaş, Yasin
The number of missing children and kidnapping is on the rise in recent years. Every parent wills definitely going through an agonizing experience to have their children missing. Therefore, there are many safety measurements to prevent this incident from happening. The help of modern technologies is one of the ways to reduce children missing and kidnapping. A child can be tracked by using the global positioning system (GPS) and global system for mobile communication (GSM) technology. Advanced child monitoring systems are expensive. Not all families have the same living standards. For this purpose, a low-cost child tracking system is proposed in this study. The implementation of the proposed approach is reported in real-time.

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