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Permanent URI for this collectionhttps://hdl.handle.net/20.500.12573/1338

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Citation - WoS: 12
Citation - Scopus: 12
Comparison of Photocatalytic and Adsorption Properties of ZnS@ZnO, CdS@ZnO, and PbS@ZnO Nanocomposites to Select the Best Material for the Bifunctional Removal of Methylene Blue
(Amer Chemical Soc, 2025) Bayram, Umit; Ozer, Cigdem; Yilmaz, Erkan; 0000-0001-8760-8024; 0000-0001-8962-3199; AGÜ; Bayram, Umit; 01. Abdullah Gül University; 10. Rektörlük
In this study, photocatalytic- and adsorption-based removal processes were conducted, which are frequently preferred in wastewater treatment due to their ease of control and high removal efficiency. An innovative method aimed at wastewater treatment was developed by combining the advantages of these two distinct approaches within the same material. The study synthesized ZnO, ZnS, CdS, PbS, and their composite structures (ZnS@ZnO, CdS@ZnO, and PbS@ZnO) using a hydrothermal synthesis method. Characterization of the samples was performed through field emission-scanning electron microscopy (FE-SEM), FE-SEM-energy dispersive X-ray (FE-SEM-EDX), X-ray diffraction (XRD), Raman spectroscopy, and Fourier-transform infrared spectroscopy (FTIR) measurement. Additionally, the optical properties of all samples (absorption spectra and band gap) were investigated by using absorbance measurements obtained from ultraviolet (UV)-visible absorption spectroscopy. Although ZnO nanoparticles are among the materials with high photocatalytic properties (exhibiting a photodegradation efficiency of 95.8% in a short duration of 90 min), their adsorption properties are low. Therefore, with the aim of enhancing both the low adsorption values and the photocatalytic properties of pure metal sulfides (ZnS, CdS, PbS), nanocomposites ZnS@ZnO, CdS@ZnO, and PbS@ZnO with different morphologies were synthesized, and their photocatalytic and adsorption-based removal performances on methylene blue (MB) dye were investigated. FE-SEM images indicated that ZnS nanoparticles exhibit a spherical morphology, CdS nanoparticles have a flower-like morphology, and PbS nanoparticles display a dendritic-like structure. The results obtained from experimental studies demonstrated that the highest efficiency in both photocatalytic- and adsorption-based removal was achieved with the ZnS@ZnO nanocomposite. The degradation rates of MB were found to be 95.3, 90.5, and 89.4% for the heterojunction composites ZnS@ZnO, CdS@ZnO, and PbS@ZnO, respectively, over a time range of 0-480 min. The optimal amount of photocatalyst that could effectively degrade MB was determined to be 100 mg, and the reusability studies revealed that the ability of the ZnS@ZnO semiconductor heterojunction photocatalyst to decompose MB into simpler molecules was limited after the fourth cycle. The adsorption-based removal rates were 96.0, 30.5, and 19.4% for the heterojunction composites ZnS@ZnO, CdS@ZnO, and PbS@ZnO, respectively. Finally, parameters influencing the adsorption-based removal of MB, such as pH, mass, and contact time, were examined, indicating that the adsorption capacity of ZnS@ZnO remained unchanged after reaching a value of 40 mgg-1.
Examining Tongue Movement Intentions in EEG-Based BCI With Machine and Deep Learning: An Approach for Dysphagia Rehabilitation
(Sciendo, 2024) Aslan, Sevgi Gokce; Yilmaz, Bulent; 0000-0001-9425-1916; AGÜ; Aslan, Sevgi Gökçe; 01. Abdullah Gül University
Dysphagia, a common swallowing disorder particularly prevalent among older adults and often associated with neurological conditions, significantly affects individuals' quality of life by negatively impacting their eating habits, physical health, and social interactions. This study investigates the potential of brain-computer interface (BCI) technologies in dysphagia rehabilitation, focusing specifically on motor imagery paradigms based on EEG signals and integration with machine learning and deep learning methods for tongue movement. Traditional machine learning classifiers, such as K-Nearest Neighbors (KNN), Support Vector Machine (SVM), Decision Tree, Naive Bayes, Random Forest, AdaBoost, Bagging, and Kernel were employed in discrimination of rest and imagination phases of EEG signals obtained from 30 healthy subjects. Scalogram images obtained using continuous wavelet transform of EEG signals corresponding to the rest and imagination phases of the experiment were used as the input images to the CNN architecture. As a result, KNN (79.4%) and SVM (63.4%) exhibited lower accuracy rates compared to ensemble methods like AdaBoost, Bagging, and Random Forest, all achieving high accuracy rates of 99.8%. These ensemble techniques proved to be highly effective in handling complex EEG datasets, particularly in distinguishing between rest and imagination phases. Furthermore, the deep learning approach, utilizing CNN and Continuous Wavelet Transform (CWT), achieved an accuracy of 83%, highlighting its potential in analyzing motor imagery data. Overall, this study demonstrates the promising role of BCI technologies and advanced machine learning techniques, especially ensemble and deep learning methods, in improving outcomes for dysphagia rehabilitation.
Citation - WoS: 1
Citation - Scopus: 1
Exploring Transdisciplinary Interaction in Higher Education: Urbanism Through Informal Learning Environment
(Emerald Group Publishing Ltd, 2025) Kesim, Berk; Bengu, Elif; 0000-0001-8772-4084; 0000-0001-9817-7207; AGÜ; Bengu, Elif; 01. Abdullah Gül University; 10. Rektörlük
PurposeThis study aims to explore interdisciplinary and transdisciplinary interactions around sustainability, focusing on the United Nations sustainable development goals (SDGs). By using the city as an informal learning space, it presents a case study to raise SDG awareness, promote interdisciplinarity, foster critical thinking and empower students.Design/methodology/approachUsing qualitative content analysis, this study explores students' interdisciplinary engagements. The research centers on student-created Logbooks, combining field data for analysis via open coding.FindingsThe informal setting facilitates transdisciplinary interaction and enriches interdisciplinary skills while retaining individuals' disciplinary tendencies.Research limitations/implicationsFactors like local geographical conditions and participant numbers could lead to minor variations in future course applications. Although initial problem topics and discussions are confined to local urban geography, they might diversify during implementation.Practical implicationsThe Logbook serves as a guide for local urban issues and embodies interdisciplinary outcomes. It can be enhanced with maps and problem zoning.Social implicationsDemonstrates effective SDG integration into higher education.Originality/valueThis study spotlights interdisciplinary learning within an unconventional context - urbanism - bridging student gaps. Supported by a paradigm shift from sustainability to unsustainability, it underscores the significance of critical engagement with SDGs.
Citation - Scopus: 4
Impact of Sustainable Energy, Fossil Fuels and Green Finance on Ecosystem: Evidence From China
(Elsevier Ltd, 2024) Wang, Zuoteng; Zeng, Sheng; Khan, Zohan; AGÜ; Khan, Zohan; 01. Abdullah Gül University
The adoption of sustainable energy has increased as a substitute for petroleum derivatives due to growing concerns about environmental degradation caused by pollution and non-renewable energy sources. This study aims to investigate the impact of sustainable energy, green finance, and fossil fuels on the ecology of China. Instead of using traditional intermediaries like CO2 and EF, we employed the ecosystem habitat index to evaluate the conservation of terrestrial ecosystems. This index measures the extent of habitat destruction, deterioration, and fragmentation. The research demonstrated that implementing ecological power and green finance in China has enhanced the country's ability to safeguard and enhance its ecosystem in the short and long term. Furthermore, the findings suggest that using non-renewable energy sources in China has heightened the risk to biodiversity and the ecosystem. The analysis indicates that prioritizing green funding and renewable energy sources is crucial for policymakers, legislators, and investors to safeguard and enhance ecosystem diversity. © 2024 Elsevier B.V., All rights reserved.
Citation - WoS: 108
Citation - Scopus: 118
Investigation of Corrosion Inhibition Effect of 3-[(2 on Corrosion of Mild Steel in the Acidic Medium)]
(Pergamon-Elsevier Science Ltd, 2013) Doner, Ali; Sahin, Ece Altunbas; Kardas, Gulfeza; Serindag, Osman; AGÜ; Serindaĝ, Osman; 01. Abdullah Gül University
The corrosion behavior of mild steel (MS) in 0.5 M H2SO4 was studied using 3-[(2-hydroxy-benzylidene)-amino]-2-thioxo-thiazolidin-4-one (HBTT) as inhibitor using the conventional potentiodynamic polarization studies, linear polarization studies (LPR), electrochemical impedance spectroscopy studies (EIS). SEM was utilized for surface characterization. The results showed that HBTT posses excellent inhibition effect towards MS corrosion. The inhibitor molecules were first adsorbed on the MS surface and blocking the reaction sites available for acid attack. Adsorption of inhibitor was found to obey Langmuir isotherm and was more chemical than physical. (C) 2012 Elsevier Ltd. All rights reserved.
Citation - WoS: 14
Citation - Scopus: 17
A Mathematical Model With Piecewise Constant Arguments of Colorectal Cancer With Chemo-Immunotherapy
(Pergamon-Elsevier Science Ltd, 2023) Bozkurt, Fatma; Yousef, Ali; Bilgil, Halis; Baleanu, Dumitru; AGÜ; Yousef, Ali; 01. Abdullah Gül University
We propose a new mathematical model with piecewise constant arguments of a system of ODEs to investigate the growth of colorectal cancer and its response to chemo-immunotherapy. Our main target in this paper is to analyze and represent the I.S.'s (immune system) efficiency during the chemotherapeutic process. Therefore, we proved and illustrated the necessity of IL-2 that supports the immune system, especially in early-detected cases of tumor density. Thus, the constructed model has been divided into sub-systems: the cell populations, the effects of the medications doxorubicin, and IL-2 concentration.Firstly, we analyze the stability of the equilibrium points (disease-free and co-existing) using the RouthHurwitz criteria. In addition, our study has shown that the system undergoes period-doubling, stationary and Neimark-Sacker bifurcations based on specific conditions. In the end, we illustrate some simulations to assist the theory of the manuscript.
Citation - WoS: 3
Citation - Scopus: 10
Raising Awareness of Sustainable Development Goals in Higher Education Institutions
(Turkish Educational Admin Research & Development Assoc, 2024) Suklun, Harika; Bengu, Elif; 0000-0003-1016-268X; 0000-0001-9817-7207; AGÜ; Bengu, Elif; 01. Abdullah Gül University; 10. Rektörlük
Higher education institutions play a crucial role in advancing sustainable development goals. They bear the responsibility of informing and encouraging all stakeholders, including faculty members, students, and industry partners, to collaborate towards achieving these goals. While many universities are integrating Sustainable Development Goals into their operations and educational programs, there is an increasing need to establish collaborative platforms with private sectors and nongovernmental organizations to further champion this agenda. Educating the future workforce is a key responsibility of these institutions, and they should actively raise students' awareness of these goals, enabling them to develop competencies related to sustainability. This study aims to explore how higher education institutions can effectively raise awareness of sustainable development goals. In addition, the research contributes to the literature by presenting a curriculum designed in a Turkish higher education institution to foster awareness of sustainable development goals. The findings hold the potential to significantly enrich existing literature on awarenessraising practices and the promotion of sustainability strategies, extending beyond higher education institutions to organizations at large.
Citation - Scopus: 13
Staging of the Liver Fibrosis From CT Images Using Texture Features
(2012) Kayaaltı, Ömer; Aksebzeci, Bekir Hakan; Karahan, Ökkeş Ibrahim; Deniz, Kemal; Öztürk, Menmet; Yilmaz, Bulent; Asyali, Musa Hakan; 0000-0003-2954-1217; 0000-0001-7476-8141; AGÜ; Aksebzeci, Bekir Hakan; Yilmaz, Bülent; Asyali, Musa Hakan; 01. Abdullah Gül University
Even though liver biopsy is critical for evaluating chronic hepatitis and fibrosis, it is an invasive, costly, and difficult to standardize approach. The developments in medical image processing and artificial intelligence methods have advanced the potential of using computer-aided diagnosis techniques in the classification of liver tissues. The aim of this study was to develop a non-invasive, cost-effective, and fast approach to specify fibrosis stage using the texture properties of computed tomography images of liver. Gray level co-occurrence matrix, discrete wavelet transform, and discrete Fourier transform were the image analysis tools in the feature extraction phase. Following dimension reduction of the texture features support vector machines and k-nearest neighbor methods were used in the classification phase of this study. Our results showed that our approach is feasible in fibrosis staging especially in pairwise stage comparisons with success rate of approximately 90%. © 2012 IEEE. © 2012 Elsevier B.V., All rights reserved.
Citation - WoS: 1
Citation - Scopus: 2
Vision-Based Autonomous Aerial Refueling
(Amer Inst Aeronautics & Astronautics, 2022) Erkin, Tevfik; Abdo, Omer; Sanli, Yilmaz; Celik, Harun; Isci, Hasan; AGÜ; Sanli, Yilmaz; 01. Abdullah Gül University
Aerial refueling tasks are very challenging due to the high risk of aircraft close proximity. Currently, within the drogue-probe method, the receiver aircraft pilot manages the refueling task in accordance with the tanker aircraft pilot. Therefore, autonomous aerial refueling is still an unaccomplished task for aircrafts. In this paper, a fully automated aerial refueling procedure based on digital visual inspection is proposed. A nonlinear dynamic model of receiver aircraft is derived to track the motion of drogue. In order to control the receiver aircraft affected by tanker aircraft vortex during approach, and ensure the receiver aircraft to automatically track and dock the tanker aircraft, an autopilot system that considers visual sensing of drogue motion is designed. The receiver aircraft is controlled by the autopilot system via translational motion of tanker aircraft projected by a cameramounted on the receiver aircraft. Thanks to this vision-based controllers, the need of tanker aircraft positioning is denied since camera projection has the capability of perception of three-dimensional direction of tanker aircraft. In order to test the autopilots include vision-based controllers and algorithms, the vision-based autonomous aerial refueling is operated under presence of turbulence and vortex. Finally, the simulation results demonstrate that the proposed guidance-navigation-control system achieve aerial refueling autonomously, and make it feasible and realizable for aircrafts.

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